National Library of Energy BETA

Sample records for dis tri ct

  1. Review of Power Corrections in DIS

    E-Print Network [OSTI]

    Thomas Kluge

    2006-06-23

    An overview is given of analyses in DIS at HERA which confront the predictions of power corrections with measured data. These include mean values and distributions of 2-jet as well as 3-jet event shape variables and jet rates.

  2. Nuclear correction factors from neutrino DIS

    E-Print Network [OSTI]

    K. Kovarik

    2011-07-15

    Neutrino Deep Inelastic Scattering on nuclei is an essential process to constrain the strange quark parton distribution functions in the proton. The critical component on the way to using the neutrino DIS data in a proton PDF analysis is understanding the nuclear effects in parton distribution functions. We parametrize these effects by nuclear parton distribution functions and we use this framework to analyze the consistency of neutrino DIS data with other nuclear data.

  3. Polarized DIS Structure Functions from Neural Networks

    SciTech Connect (OSTI)

    Del Debbio, L.; Guffanti, A. [School of Physics, University of Edinburgh, Edinburgh (United Kingdom); Piccione, A. [Universita degli Studi di Torino, Torino (Italy); INFN Torino, Torino (Italy)

    2007-06-13

    We present a parametrization of polarized Deep-Inelastic-Scattering (DIS) structure functions based on Neural Networks. The parametrization provides a bias-free determination of the probability measure in the space of structure functions, which retains information on experimental errors and correlations. As an example we discuss the application of this method to the study of the structure function g{sub 1}{sup p}(x,Q{sup 2})

  4. The Tri--Methane Rearrangement

    E-Print Network [OSTI]

    Cirkva, Vladimir

    The Tri--Methane Rearrangement #12;Církva, Vladimír; Zuraw, Michael J.; Zimmerman, Howard E.* Department of Chemistry, University of Wisconsin, Madison, WI 53706 #12;INTRODUCTION The tri--methane of a cyclopentene 5a, but only in crystalline medium. However, in the solution photochemistry of tri--methane system

  5. The Tri--Methane Rearrangement

    E-Print Network [OSTI]

    Cirkva, Vladimir

    The Tri--Methane Rearrangement #12;Cirkva, Vladimir; Zuraw, Michael J.; Zimmerman, Howard E.* Department of Chemistry, University of Wisconsin, Madison, WI 53706 #12;INTRODUCTION The tri--methane of a cyclopentene 5a, but only in crystalline medium. However, in the solution photochemistry of tri--methane system

  6. Analytic calculation of 1-jettiness in DIS at O (?s)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kang, Daekyoung; Los Alamos National Lab.; Lee, Christopher; Stewart, Iain W.

    2014-11-24

    We present an analytic O(?s) calculation of cross sections in deep inelastic scattering (DIS) dependent on an event shape, 1-jettiness, that probes final states with one jet plus initial state radiation. This is the first entirely analytic calculation for a DIS event shape cross section at this order. We present results for the differential and cumulative 1-jettiness cross sections, and express both in terms of structure functions dependent not only on the usual DIS variables x, Q 2 but also on the 1-jettiness ?. Combined with previous results for log resummation, predictions are obtained over the entire range of themore »1-jettiness distribution.« less

  7. Tri-Generation Success Story: World's First Tri-Gen EnergyStation...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Tri-Generation Success Story: World's First Tri-Gen Energy Station-Fountain Valley Tri-Generation Success Story: World's First Tri-Gen Energy Station-Fountain Valley This Fuel Cell...

  8. Brian Foster -DIS01 -Bologna HERA II Physics

    E-Print Network [OSTI]

    V2 Q2 = 200 GeV2 Q2 = 2000 GeV2 #12;Brian Foster - DIS01 - Bologna 8 Active Filter Calorimeter ZEUS 6 systematics plus precision electron tagger. "Standard" Pb/scintillator calorimeter plus "active filter" of aerogel. Dipole spectrometer to measure converting e+e- pairs. "6m tagger" W/fibre to measure the energy

  9. Prompt photons in DIS For the ZEUS Collaboration

    E-Print Network [OSTI]

    1 Prompt photons in DIS P J BUSSEY For the ZEUS Collaboration PHOTON 2009 #12;2 We study prompt photon production because: - the emergence of a photon directly from a QCD-governed interaction allows particular diagrams to be studied: new perspectives on QCD processes - the photon does not suffer from

  10. STATE OF OHIO, IN THE UNITED STATES DISTRICT FOR THE .SOUTHERN DIS~CT OF

    Energy Savers [EERE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on DeliciousMathematicsEnergyInterestedReplacement-2-AA-1 SECTION J APPENDIXAllegationsEnergy STATE.. .. /_

  11. Nuclear higher-twist effects in eA DIS

    E-Print Network [OSTI]

    B. G. Zakharov

    2009-03-22

    We discuss the relation between the treatments of the higher twist nuclear effects in eA DIS based on the pQCD collinear approximation and the light-cone path integral formalism. We show that in the collinear approximation the N=1 rescattering contribution to the gluon emission vanishes. It is demonstrated that the nonzero gluon spectrum obtained by Guo, Wang and Zhang is a consequence of unjustified neglect of some terms in the collinear expansion.

  12. NETL CT Imaging Facility

    ScienceCinema (OSTI)

    None

    2014-05-21

    NETL's CT Scanner laboratory is equipped with three CT scanners and a mobile core logging unit that work together to provide characteristic geologic and geophysical information at different scales, non-destructively.

  13. NETL CT Imaging Facility

    SciTech Connect (OSTI)

    2013-09-04

    NETL's CT Scanner laboratory is equipped with three CT scanners and a mobile core logging unit that work together to provide characteristic geologic and geophysical information at different scales, non-destructively.

  14. DIS 2001, Bologna, 29. 04. 2001Ana Dubak, MPI for Physics, Munich MPI for Physics Munich

    E-Print Network [OSTI]

    DIS 2001, Bologna, 29. 04. 2001Ana Dubak, MPI for Physics, Munich Ana Dubak MPI for Physics Munich& ¤& ¥ & #12;DIS 2001, Bologna, 29. 04. 2001Ana Dubak, MPI for Physics, Munich H1 Luminosity: (98/99): LL == 16 2001, Bologna, 29. 04. 2001Ana Dubak, MPI for Physics, Munich LAr calorimeter: High granularity 45000

  15. INT J TUBERC LUNG DIS 15(8):9961004 2011 The Union

    E-Print Network [OSTI]

    Cohen, Ted

    INT J TUBERC LUNG DIS 15(8):996­1004 ©2011 The Union doi:10.5588/ijtld.11.0062 STATE OF THE ART University, Taipei, Taiwan; International Union Against Tuberculosis and Lung Disease, Paris, France series in the Journal. Int J Tuberc Lung Dis 2011; 15(1): 3. No 1: Lienhardt C, Cobelens F G J

  16. TriWo AG | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEt Al., 2013)OpenEnergyTrail CanyonsourceRiver Solar |TrexaTri-StateTriWo AG

  17. (ura avio teleco-mandado no tri-

    E-Print Network [OSTI]

    Instituto de Sistemas e Robotica

    Lançar um drone (ura avião teleco- mandado não tri- pulado) na Antárti- da e esperar que ele) controlou a ansie- dade e arriscou lançar o drone . O objetivo do 'Projeto 3D An- tártida' é ajudar'é perceber como o aumento da temperatura está a alterar o ecossistema A equipa lançou um drone de 20 mileuros

  18. -A Science &Feature ? TRY THE WEATHER ?

    E-Print Network [OSTI]

    -A Science &Feature ? TRY THE WEATHER ? By Dr. Charles F. Brook8 of Clark University. Dl mountains both i n quiet weather and i n windy is coolad t o temperatures lower than those elsewhere, density and movoments of such clouds t e l l much as t o the trend of the weather, mountains where

  19. Analytic calculation of 1-jettiness in DIS at O (?s)

    SciTech Connect (OSTI)

    Kang, Daekyoung; Lee, Christopher; Stewart, Iain W.

    2014-11-24

    We present an analytic O(?s) calculation of cross sections in deep inelastic scattering (DIS) dependent on an event shape, 1-jettiness, that probes final states with one jet plus initial state radiation. This is the first entirely analytic calculation for a DIS event shape cross section at this order. We present results for the differential and cumulative 1-jettiness cross sections, and express both in terms of structure functions dependent not only on the usual DIS variables x, Q 2 but also on the 1-jettiness ?. Combined with previous results for log resummation, predictions are obtained over the entire range of the 1-jettiness distribution.

  20. TriBITS Developers Guide and Reference

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout / TransformingTransuranic WasteTriBITS Developers Guide and

  1. CT Solar Lease

    Broader source: Energy.gov [DOE]

    CT Solar Lease allows homeowners to lease a photovoltaic (PV) or solar thermal system, with fixed monthly payments, for a term of 20 years, at no upfront down payment.* This program, which takes...

  2. -CT CT)Computed Tomography(. ,. , -100 ,

    E-Print Network [OSTI]

    Pinsky, Ross

    sigma . ." , : ·B.sc "BA- · " Lean/six sigma - ·-Green/Black Belt ·. · , , .' , ·" . " * . : ·) B.A ,(-. ·4-6. ·) QFD, CtQ breakdown, DfSS, SPC, AQP, FMEA, Control Plan.( ·Six Sigma GB/EE/Mechanics/Physics/SW/Algorithms/Materials /Application Development) · · - · · Process Improvement Engineer : · . · -six

  3. Characterization of Tri-lab Tantalum Plate.

    SciTech Connect (OSTI)

    Buchheit, Thomas E.; Cerreta, Ellen K.; Deibler, Lisa Anne; Chen, Shu-Rong; Michael, Joseph R.

    2014-09-01

    This report provides a detailed characterization Tri-lab Tantalum (Ta) plate jointly purchased from HCStark Inc. by Sandia, Los Alamos and Lawrence Livermore National Laboratories. Data in this report was compiled from series of material and properties characterization experiments carried out at Sandia (SNL) and Los Alamos (LANL) Laboratories through a leveraged effort funded by the C2 campaign. Results include microstructure characterization detailing the crystallographic texture of the material and an increase in grain size near the end of the rolled plate. Mechanical properties evaluations include, compression cylinder, sub-scale tension specimen, micohardness and instrumented indentation testing. The plate was found to have vastly superior uniformity when compare with previously characterized wrought Ta material. Small but measurable variations in microstructure and properties were noted at the end, and at the top and bottom edges of the plate.

  4. NFolkstoneCt PepperPikeRd

    E-Print Network [OSTI]

    Kamat, Vineet R.

    Sturbridge Ct Paisley Ct CedarBendDr Stanton Ct BonisteelBlvd Middleton Dr Pointe Ln Charter Pl Larchmont Dr

  5. A manifestation of a gluon saturation in e-A DIS

    E-Print Network [OSTI]

    Levin, E; Levin, Eugene; Maor, Uri

    2000-01-01

    This is a short presentation of our talks given at eRHIC Workshop at the BNL. We give here a status report of our attempts to understand how gluon saturation will manifest itself in deep inelastic scattering with nuclei. This summary reflects our current understanding and shows directions of our research rather then a final answer to the question. Nevertheless, we are able to share with our reader our tentative answer to the question:``Why do we need to measure DIS with nuclei and why these data will be complementary to the information obtained from proton DIS".

  6. A manifestation of a gluon saturation in e-A DIS

    E-Print Network [OSTI]

    Eugene Levin; Uri Maor

    2000-09-19

    This is a short presentation of our talks given at eRHIC Workshop at the BNL. We give here a status report of our attempts to understand how gluon saturation will manifest itself in deep inelastic scattering with nuclei. This summary reflects our current understanding and shows directions of our research rather then a final answer to the question. Nevertheless, we are able to share with our reader our tentative answer to the question:``Why do we need to measure DIS with nuclei and why these data will be complementary to the information obtained from proton DIS".

  7. Tri-Generation Success Story: World's First Tri-Gen Energy Station - Fountain Valley

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCEDInstallers/ContractorsPhotovoltaicsState ofSavingsTransmissionin PEMFC27,Inc.Tri-Generation

  8. Prompt photons + jets at ZEUS, Eric Brownson, U. Wisconsin DIS 2006, April 21, 2006 -1 Prompt photon plus jet

    E-Print Network [OSTI]

    Prompt photons + jets at ZEUS, Eric Brownson, U. Wisconsin DIS 2006, April 21, 2006 - 1 Prompt photon plus jet photoproduction with the ZEUS detector Eric Brownson University of Wisconsin On Behalf of the ZEUS Collaboration DIS 2006 Tsukuba city, Japan #12;Prompt photons + jets at ZEUS, Eric Brownson, U

  9. Motivation Selection CC Cross Sections Summary Charged Current DIS Cross Sections with a

    E-Print Network [OSTI]

    Raval, Amita

    Motivation Selection CC Cross Sections Summary Charged Current DIS Cross Sections polarised e+ 21st April 2010 1 / 15 #12;Motivation Selection CC Cross Sections Summary Charged Current Interaction: Motivation Extraction of MW d2(e+p) dxdQ2 = (1 + P) × G2 F M4 W 2(Q2 + M2 W )2 u + c + (1 - y)2

  10. On Non-singlets in Kaon Production in Semi-inclusive DIS reactions

    SciTech Connect (OSTI)

    Christova, Ekaterina [Institute for Nuclear Research and Nuclear Energy, Sofia (Bulgaria); Leader, Elliot [Imperial College, London (United Kingdom)

    2007-06-13

    We consider semi-inclusive unpolarized DIS for the production of charged kaons and the different possibilities, both in LO and NLO, to test the conventionally used assumptions s - s-bar = 0 and D{sub d}{sup K{sup +}-K{sup -}} = 0. The considered tests have the advantage that they do not require any knowledge of the fragmentation functions.

  11. SIMULATION OF ENERGY SELECTIVE X-RAY IMAGES FOR MATERIAL DIS-CRIMINATION

    E-Print Network [OSTI]

    Hickman, Mark

    SIMULATION OF ENERGY SELECTIVE X-RAY IMAGES FOR MATERIAL DIS- CRIMINATION Rune S Thing1 , Syen J model can be applied to any material combination and any number of energy bins. Figure: Top row Carlo model is presented to evaluate the clinical benefits of optimal energy bins in spectral X

  12. Which LED Lighting Products Would You Consider Trying?

    Broader source: Energy.gov [DOE]

    Which LED lighting products would you consider trying? Or, if you're already using LEDs, what do you think of them?

  13. The Tri-Party Agencies want your input on proposed changes to the Tri-Party

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With U.S.Week DayDr. Jeffrey GriffinHydratesTri-Party Agencies want

  14. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY The Faculty Council on Tri, Chancellor, University of Washington, Bothell; Vicky Carwein, Chancellor, University of Washington, Tacoma; and Weldon Ihrig, Executive Vice President, University of Washington. ABSENT: Ex officio members Fugate

  15. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    Review (College Curriculum Committee if Seattle, the UW Bothell SCAP, if UW Bothell, and the UW Tacoma SCAP, if UW Tacoma, and the Tri-Campus SCAP if there are trans-campus objections, and UW Seattle SCAP, specifically, review by UW Seattle SCAP, UW Bothell College Council, and UW Tacoma Faculty Assembly; or Tri

  16. The Tri--methane Rearrangement: Mechanistic and Exploratory Organic

    E-Print Network [OSTI]

    Cirkva, Vladimir

    counterpart. Scheme 1 shows the mechanism of the di--methane rearrangement and its potential diversion allylic diradical 4, closure to tri--methane product 6 may compete with 1,3-closure to di--methane product rearrangement. On direct irradiation, tris-diphenylvinyl methane 9 led to 52% of tri--methane product 11

  17. RENEWAL THEORY IN ANALYSIS OF TRIES AND STRINGS: EXTENDED ABSTRACT

    E-Print Network [OSTI]

    Janson, Svante

    RENEWAL THEORY IN ANALYSIS OF TRIES AND STRINGS: EXTENDED ABSTRACT SVANTE JANSON Abstract. We give a survey of a number of simple applications of renewal theory to problems on random strings, in particular to tries and Khodak and Tunstall codes. 1. Introduction Although it long has been realized that renewal

  18. Abstract Microgrids are a new concept for future energy dis-tribution systems that enable renewable energy integration and

    E-Print Network [OSTI]

    Collins, Emmanuel

    1 Abstract ­ Microgrids are a new concept for future energy dis- tribution systems that enable renewable energy integration and improved energy management capability. Microgrids consist of multiple power quality and power distribution reliability, microgrids need to operate in both grid

  19. CT NC0

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth DakotaRobbins and Myers Co -VANaval ,, *' ;x-L* d! CT NC0 - i , ,.

  20. Exploring PropertiesSurface Coatings: Nano-Toss! Try this!

    E-Print Network [OSTI]

    Exploring Properties­Surface Coatings: Nano-Toss! Try this! 1. Presenter. Visitors experiment with modifying nano-ball's surface with different coatings: polymers, or decorative rhinestone-like stickers, or electrical tape.) 3. Visitors throw the coated

  1. Some remarks on methods of QCD analysis of polarized DIS data

    SciTech Connect (OSTI)

    Leader, Elliot; Sidorov, Aleksander V.; Stamenov, Dimiter B. [Imperial College, Prince Consort Road, London SW7 2BW (United Kingdom); Bogoliubov Theoretical Laboratory, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); CERN, Theory Division, CH 1211 Geneva 23 (Switzerland) and Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Boulevard Tsarigradsko Chaussee 72, Sofia 1784 (Bulgaria)

    2009-09-01

    The results on polarized parton densities obtained using different methods of QCD analysis of the present polarized DIS data are discussed. Their dependence on the method used in the analysis, accounting or not for the kinematic and dynamic 1/Q{sup 2} corrections to spin structure function g{sub 1}, is demonstrated. It is pointed out that the precise data in the preasymptotic region require a more careful matching of the QCD predictions to the data in this region in order to determine the polarized parton densities correctly.

  2. Inclusive hadron distributions in p+p collisions from saturation models of HERA DIS data.

    SciTech Connect (OSTI)

    Tribedy, P.; Venugopalan, R.

    2010-12-06

    Dipole models based on various saturation scenarios provide reasonable fits to small-x DIS inclusive, diffractive and exclusive data from HERA. Proton un-integrated gluon distributions extracted from such fits are employed in a k{sub {perpendicular}}-factorization framework to calculate inclusive gluon distributions at various energies. The n-particle multiplicity distribution predicted in the Glasma flux tube approach shows good agreement with data over a wide range of energies. Hadron inclusive transverse momentum distributions expressed in terms of the saturation scale demonstrate universal behavior over a wider kinematic range systematically with increasing center of mass energies.

  3. Tri-Party Agreement Agencies Annual Hanford Public Involvement Survey

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With U.S.WeekProducts[TRI-PARTY AGREEMENT AGENCIES - PUBLIC7 Tri-Party

  4. Tri-Party Agreement Hanford Public Involvement Plan

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With U.S.WeekProducts[TRI-PARTY AGREEMENT AGENCIES - PUBLIC7 Tri-Party

  5. Resonant Soft X-Ray Scattering of Tri-Block Copolymers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    principle, tri-block copolymers (tri-BCPs), consisting of three chemically distinct polymers covalently joined together at the ends of each polymer chain, can serve as scaffolds...

  6. Private rail tries for comeback in Florida By Matthew Peddie

    E-Print Network [OSTI]

    Fernandez, Eduardo

    profitable flights. Dumbaugh says there are also promising signs for high-speed inter-city rail in Texas funded intercity rail line turns a profit, high speed rail could even be back on the table in FloridaPrivate rail tries for comeback in Florida By Matthew Peddie Marketplace Morning Report

  7. 2004 INDEX OF INNOVATION AND TECHNOLOGY TRI-CITIES, WASHINGTON

    E-Print Network [OSTI]

    technology startups in the last five years o Has not yet experienced many of the downsides of growth Tax Burden 14 Labor Costs 15 Growth 16 Employment in Technology Firms 17 Growth in Startups 172004 INDEX OF INNOVATION AND TECHNOLOGY TRI-CITIES, WASHINGTON JULY 2004 #12;PNNL-SA-42092 2004

  8. RENEWAL THEORY IN ANALYSIS OF TRIES AND SVANTE JANSON

    E-Print Network [OSTI]

    Janson, Svante

    ´ement, Flajolet and Vall´ee [7] for various interesting probability models of random strings. Renewal theory of the purposes of this paper is to make propaganda for the use of renewal theory to study e.g. Markov modelsRENEWAL THEORY IN ANALYSIS OF TRIES AND STRINGS SVANTE JANSON To my colleague and friend Allan Gut

  9. RENEWAL THEORY IN ANALYSIS OF TRIES AND STRINGS: EXTENDED ABSTRACT

    E-Print Network [OSTI]

    Janson, Svante

    of this paper is to make propaganda for the use of renewal theory to study e.g. Markov models, even if we doRENEWAL THEORY IN ANALYSIS OF TRIES AND STRINGS: EXTENDED ABSTRACT SVANTE JANSON Abstract. We give a survey of a number of simple applications of renewal theory to problems on random strings, in particular

  10. Tri College 2011 Middle School Team Div I

    E-Print Network [OSTI]

    Hu, Wen-Chen

    Tri College 2011 Middle School Team Div I 1 Ben Franklin 223 2 Schroder Middle GForks 210 3 Horizon;Middle School Team Div II 1 Dilworth-Glydon-Felton 200 2 Mennewaska 185 3 Park River 184 4 Wheaton 167 5 Middle Moorhead 209 4 Discovery 197 5 Sullivan 190 189 Middle School Ind Div I 188 1 Andrew Hu South GF

  11. TRI-CITIES, WASHINGTON INNOVATION AND TECHNOLOGY INDEX

    E-Print Network [OSTI]

    #12;TRI-CITIES, WASHINGTON INNOVATION AND TECHNOLOGY INDEX 2001 October 3, 2001 Economic and Technology Index 2001 2 Dear Reader: The known story of the Washington state technology industry has centered of growth such as traffic congestion and high cost of living o Has two factors impeding its technology

  12. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    , the Tri-Campus Presidential Task Force Report. UW, Bothell and UW, Tacoma to have legislative hearings and UW, Tacoma. Nelson said, "The report [from the campuses] goes to the HEC Board; they will useth (at UW, Tacoma) and the other on April 29th (at UW, Bothell). The House Higher Education Committee

  13. University Of Washington Faculty Council on Tri-Campus Policy

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    , Director of Admissions, UW Bothell c) Tacoma Campus: Derek Levy, Associate Vice Chancellor for Enrollment Services, UW Tacoma 4) Tri-campus review subcommittee discussion 5) Good of the Order / Discussion, although the proportionality agreement expired last September. The Bothell and Tacoma campuses had

  14. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    distributed a revision of this draft language, which was prepared by Olswang. UW Tacoma and UW Bothell (College Curriculum Committee if Seattle, the UW Bothell SCAP, if UW Bothell, and the UW Tacoma SCAP, if UW Tacoma, and the Tri-Campus SCAP if there are trans-campus objections, and UW Seattle

  15. RENEWAL THEORY IN ANALYSIS OF TRIES AND SVANTE JANSON

    E-Print Network [OSTI]

    Janson, Svante

    RENEWAL THEORY IN ANALYSIS OF TRIES AND STRINGS SVANTE JANSON To my colleague and friend Allan Gut on the occasion of his retirement Abstract. We give a survey of a number of simple applications of renewal theory been realized that renewal theory is a useful tool in the study of random strings and related

  16. UNL/OSU Researchers Try Promising Technique to Remove Groundwater

    E-Print Network [OSTI]

    Nebraska-Lincoln, University of

    UNL/OSU Researchers Try Promising Technique to Remove Groundwater Contamination Under Former Oklahoma State University have joined to test promising new methods of removing longstanding groundwater into specially drilled injection wells, where it mixes with contaminants in the groundwater under the former

  17. BUSINESS SENSITIVE 1 Tri-Cities Research District

    E-Print Network [OSTI]

    . Oklahoma City Presbyterian Foundation Research Park Virginia Biotechnology Park (Richmond) Industry in terms of business assistance or services Anchor with R&D facilities aligned with industry focus of parkBUSINESS SENSITIVE 1 Tri-Cities Research District Speaker Series: Advancing Research Parks

  18. A systematic phenomenological study of the $\\cos 2 ?$ asymmetry in unpolarized semi--inclusive DIS

    E-Print Network [OSTI]

    Vincenzo Barone; Alexei Prokudin; Bo-Qiang Ma

    2008-04-18

    We study the $\\cos 2 \\phi$ azimuthal asymmetry in unpolarized semi-inclusive DIS, taking into account both the perturbative contribution (gluon emission and splitting) and the non perturbative effects arising from intrinsic transverse motion and transverse spin of quarks. In particular we explore the possibility to extract from $cos 2 \\phi>$ some information about the Boer--Mulders function $h_1^{\\perp}$, which represents a transverse--polarization asymmetry of quarks inside an unpolarized hadron. Predictions are presented for the HERMES, COMPASS and JLab kinematics, where $cos 2 \\phi>$ is dominated by the kinematical higher--twist contribution, and turns to be of order of few percent. We show that a larger asymmetry in $\\pi^-$ production, compared to $\\pi^+$ production, would represent a signature of the Boer--Mulders effect.

  19. Quark helicity flip and the transverse spin dependence of inclusive DIS

    SciTech Connect (OSTI)

    Andrei Afanasev; Mark Strikman; Christian Weiss

    2007-05-21

    Inclusive DIS with unpolarized beam exhibits a subtle dependence on the transverse target spin, arising from the interference of one-photon and two-photon exchange amplitudes in the cross section. We argue that this observable probes mainly the quark helicity-flip amplitudes induced by the non-perturbative vacuum structure of QCD (spontaneous chiral symmetry breaking). This conjecture is based on (a) the absence of significant Sudakov suppression of the helicity-flip process if soft gluon emission in the quark subprocess is limited by the chiral symmetry breaking scale mu^2_{chiral} >> Lambda^2_{QCD}; (b) the expectation that the quark helicity-conserving twist-3 contribution is small. The normal target spin asymmetry is estimated to be of the order 10^{-4} in the kinematics of the planned Jefferson Lab Hall A experiment.

  20. Regge Analysis of Diffractive and Leading Baryon Structure Functions from DIS

    E-Print Network [OSTI]

    M. Batista; R. J. M. Covolan; J. Montanha

    2002-03-08

    In this paper we present a combined analysis of the H1 data on leading baryon and diffractive structure functions from DIS, which are handled as two components of the same semi-inclusive process. The available structure function data are analyzed in a series of fits in which three main exchanges are taking into account: pomeron, reggeon and pion. For each of these contributions, Regge factorization of the correspondent structure function is assumed. By this procedure, we extract information about the interface between the diffractive, pomeron-dominated, region and the leading proton spectrum, which is mostly ruled by secondary exchanges. One of the main results is that the relative reggeon contribution to the semi-inclusive structure function is much smaller than the one obtained from a analysis of the diffractive structure function alone.

  1. Tri-Party Agreement for Energy Savings Performance Contracts | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankADVANCEDInstallers/ContractorsPhotovoltaicsState ofSavingsTransmissionin PEMFC27,Inc.Tri-Generationof

  2. Limited View Angle Iterative CT Reconstruction

    E-Print Network [OSTI]

    . Connelly, "CT Technologies," in Aspects of Explosives Detection, Elsevier 2009. Dual energy CT Z. Ying, R. Nam and C. R. Crawford, "Dual energy computed tomography for explosive detection," Journal of X

  3. Tri-State Electric Member Corp | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEt Al., 2013)OpenEnergyTrail CanyonsourceRiver Solar |TrexaTri-State Electric

  4. Tri-County Rural Elec Coop Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power SystemsTri-County Rural Elec

  5. TriEagle Energy, LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power SystemsTri-County Rural

  6. TRI State Motor Transit to Resume Shipping Waste to WIPP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With LivermoreSustainableDEPARTMENT OFEnergy- EnergyTri-State Motor

  7. TRI-PARTY AGREEMENT HANFORD PUBLIC INVOLVEMENT PLAN

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With LivermoreSustainableDEPARTMENT OFEnergy- EnergyTri-State

  8. Fuel Cell Tri-Generation System Case Study using the H2A Stationary...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Tri-Generation System Case Study using the H2A Stationary Model Fuel Cell Tri-Generation System Case Study using the H2A Stationary Model Overview of H2A stationary model concept,...

  9. World's First Tri-Generation Fuel Cell and Hydrogen Fueling Station...

    Energy Savers [EERE]

    World's First Tri-Generation Fuel Cell and Hydrogen Fueling Station World's First Tri-Generation Fuel Cell and Hydrogen Fueling Station April 18, 2013 - 12:00am Addthis EERE...

  10. The option to try again : valuing a sequence of dependent trials

    E-Print Network [OSTI]

    Smith, James L.

    2004-01-01

    In various fields of economic endeavor, agents enjoy the option to ?try, try again.? Failure in a particular pursuit often brings renewed effort to finally succeed. Many areas of R&D could be characterized in this fashion. ...

  11. Transverse target spin asymmetry in inclusive DIS with two-photon exchange

    SciTech Connect (OSTI)

    Andrei Afanasev; Mark Strikman; Christian Weiss

    2007-09-06

    We study the transverse target spin dependence of the cross section for the inclusive electron-nucleon scattering with unpolarized beam. Such dependence is absent in the one-photon exchange approximation (Christ-Lee theorem) and arises only in higher orders of the QED expansion, from the interference of one-photon and absorptive two-photon exchange amplitudes as well as from real photon emission (bremsstrahlung). We demonstrate that the transverse spin-dependent two-photon exchange cross section is free of QED infrared and collinear divergences. We argue that in DIS kinematics the transverse spin dependence should be governed by a "parton-like" mechanism in which the two-photon exchange couples mainly to a single quark. We calculate the normal spin asymmetry in an approximation where the dominant contribution arises from quark helicity flip due to interactions with non-perturbative vacuum fields (constituent quark picture) and is proportional to the quark transversity distribution in the nucleon. Such helicity-flip processes are not significantly Sudakov-suppressed if the infrared scale for gluon emission in the photon-quark subprocess is of the order of the chiral symmetry breaking scale, mu^2_chiral>>Lambda^2_QCD. We estimate the asymmetry in the kinematics of the planned Jefferson Lab Hall A experiment to be of the order 10^-4, with different sign for proton and neutron. We also comment on the spin dependence in the limit of soft high-energy scattering.

  12. IFT2015 Miklos Csuros 21 fevrier 2011 11 Tri par fusion

    E-Print Network [OSTI]

    Csürös, Miklós

    IFT2015 Mikl´os Csur¨os 21 f´evrier 2011 11 Tri par fusion 11.1 Inversion d'une liste tri´ee Algo4 i i + 1; j j - 1 11.2 Fusion de deux tableaux tri´es. On peut fusionner deux listes (implant´ees comme tableaux ou listes cha^in´ees), par la r´ecurrence fusion(A, B) = B si A est vide A si B est

  13. The distribution of linearly polarized gluons and elliptic azimuthal anisotropy in DIS dijet production at high energy

    E-Print Network [OSTI]

    Adrian Dumitru; Tuomas Lappi; Vladimir Skokov

    2015-08-18

    We determine the distribution of linearly polarized gluons of a dense target at small $x$ by solving the B-JIMWLK rapidity evolution equations. From these solutions we estimate the amplitude of $\\sim \\cos 2\\phi$ azimuthal asymmetries in DIS dijet production at high energies. We find sizeable long-range in rapidity azimuthal asymmetries with a magnitude in the range of $v_2=\\langle\\cos 2\\phi\\rangle \\sim 10\\%$.

  14. The distribution of linearly polarized gluons and elliptic azimuthal anisotropy in DIS dijet production at high energy

    E-Print Network [OSTI]

    Dumitru, Adrian; Skokov, Vladimir

    2015-01-01

    We determine the distribution of linearly polarized gluons of a dense target at small $x$ by solving the B-JIMWLK rapidity evolution equations. From these solutions we estimate the amplitude of $\\sim \\cos 2\\phi$ azimuthal asymmetries in DIS dijet production at high energies. We find sizeable long-range in rapidity azimuthal asymmetries with a magnitude in the range of $v_2=\\langle\\cos 2\\phi\\rangle \\sim 10\\%$.

  15. Dual energy CT for attenuation correction with PET/CT

    SciTech Connect (OSTI)

    Xia, Ting; Alessio, Adam M.; Kinahan, Paul E.

    2014-01-15

    Purpose: The authors evaluate the energy dependent noise and bias properties of monoenergetic images synthesized from dual-energy CT (DECT) acquisitions. These monoenergetic images can be used to estimate attenuation coefficients at energies suitable for positron emission tomography (PET) and single-photon emission computed tomography (SPECT) imaging. This is becoming more relevant with the increased use of quantitative imaging by PET/CT and SPECT/CT scanners. There are, however, potential variations in the noise and bias of synthesized monoenergetic images as a function of energy. Methods: The authors used analytic approximations and simulations to estimate the noise and bias of synthesized monoenergetic images of water-filled cylinders with different shapes and the NURBS-based cardiac-torso (NCAT) phantom from 40 to 520 keV, the range of SPECT and PET energies. The dual-kVp spectra were based on the GE Lightspeed VCT scanner at 80 and 140 kVp with added filtration of 0.5 mm Cu. The authors evaluated strategies of noise suppression with sinogram smoothing and dose minimization with reduction of tube currents at the two kVp settings. The authors compared the impact of DECT-based attenuation correction with single-kVp CT-based attenuation correction on PET quantitation for the NCAT phantom for soft tissue and high-Z materials of bone and iodine contrast enhancement. Results: Both analytic calculations and simulations displayed the expected minimum noise value for a synthesized monoenergetic image at an energy between the mean energies of the two spectra. In addition the authors found that the normalized coefficient of variation in the synthesized attenuation map increased with energy but reached a plateau near 160 keV, and then remained constant with increasing energy up to 511 keV and beyond. The bias was minimal, as the linear attenuation coefficients of the synthesized monoenergetic images were within 2.4% of the known true values across the entire energy range. Compared with no sinogram smoothing, sinogram smoothing can dramatically reduce noise in the DECT-derived attenuation map. Through appropriate selection of tube currents for high and low kVp scans, DECT can deliver roughly the same amount of radiation dose as that of a single kVp CT scan, but could be used for PET attenuation correction with reduced bias in contrast agent regions by a factor of ?2.6 and slightly reduced RMSE for the total image. Conclusions: When DECT is used for attenuation correction at higher energies, there is a noise amplification that is dependent on the energy of the synthesized monoenergetic image of linear attenuation coefficients. Sinogram smoothing reduces the noise amplification in DECT-derived attenuation maps without increasing bias. With an appropriate selection of CT techniques, a DECT scan with the same radiation dose as a single CT scan can result in a PET image with improved quantitative accuracy.

  16. Hanford Diversification and the Tri-Cities Economy FY 1999

    SciTech Connect (OSTI)

    SCOTT, M.J.

    2000-06-05

    The missions of the U.S. Department of Energy's Richland Operations Office (DOE/RL) are to safely manage the Hanford Site, to manage and clean up its legacy wastes, and to develop and deploy new science and technology in the environmental and energy fields. Collectively, DOE/RL and its contractors are the most important single entity in the Tri-Cities local economy (Pasco, Kennewick, and Richland, Washington, and the surrounding area). Although the relevant economic region affected by DOE/RL and its contractors actually embraces a geographic area reaching from Yakima in the west to Walla Walla in the east and from Moses Lake in the north to Pendleton, Oregon, in the south, over 90% of economic impacts likely occur in Benton and Franklin Counties. These two counties are defined as the ''local'' Tri-Cities economy for purposes of this study. In the federal fiscal year (FY) 1999 (October 1, 1998 through September 30, 1999), the total impact of DOE'S local $1.59 billion budget was felt through payrolls of $542 million and local purchases of goods and services of $226 million. The total local spending of $768 million was up slightly from the FY 1998 total of $765 million. Taking into account the multiplier effects of this spending, the DOE/RL budget sustained an estimated 32% of all local employment (28,250 out of 88,100 jobs) and about 35% of local earned income (almost $1.08 billion out of $3.08 billion). The decrease in these percentages from last year's report reflects an update of the model's economic structure based on the 1997 economic census year, a correction of a programming error in the model found during the update, and a broader definition of earnings that includes proprietor income, not just wages (see the Appendix for revisions to the previous forecasts). DOE budget increases in FY 2000 are expected to result in no change to the number of local DOE contractor jobs and about a $29 million increase in direct local spending.

  17. Examination of Hydrate Formation Methods: Trying to Create Representative Samples

    SciTech Connect (OSTI)

    Kneafsey, T.J.; Rees, E.V.L.; Nakagawa, S.; Kwon, T.-H.

    2011-04-01

    Forming representative gas hydrate-bearing laboratory samples is important so that the properties of these materials may be measured, while controlling the composition and other variables. Natural samples are rare, and have often experienced pressure and temperature changes that may affect the property to be measured [Waite et al., 2008]. Forming methane hydrate samples in the laboratory has been done a number of ways, each having advantages and disadvantages. The ice-to-hydrate method [Stern et al., 1996], contacts melting ice with methane at the appropriate pressure to form hydrate. The hydrate can then be crushed and mixed with mineral grains under controlled conditions, and then compacted to create laboratory samples of methane hydrate in a mineral medium. The hydrate in these samples will be part of the load-bearing frame of the medium. In the excess gas method [Handa and Stupin, 1992], water is distributed throughout a mineral medium (e.g. packed moist sand, drained sand, moistened silica gel, other porous media) and the mixture is brought to hydrate-stable conditions (chilled and pressurized with gas), allowing hydrate to form. This method typically produces grain-cementing hydrate from pendular water in sand [Waite et al., 2004]. In the dissolved gas method [Tohidi et al., 2002], water with sufficient dissolved guest molecules is brought to hydrate-stable conditions where hydrate forms. In the laboratory, this is can be done by pre-dissolving the gas of interest in water and then introducing it to the sample under the appropriate conditions. With this method, it is easier to form hydrate from more soluble gases such as carbon dioxide. It is thought that this method more closely simulates the way most natural gas hydrate has formed. Laboratory implementation, however, is difficult, and sample formation is prohibitively time consuming [Minagawa et al., 2005; Spangenberg and Kulenkampff, 2005]. In another version of this technique, a specified quantity of gas is placed in a sample, then the sample is flooded with water and cooled [Priest et al., 2009]. We have performed a number of tests in which hydrate was formed and the uniformity of the hydrate formation was examined. These tests have primarily used a variety of modifications of the excess gas method to make the hydrate, although we have also used a version of the excess water technique. Early on, we found difficulties in creating uniform samples with a particular sand/ initial water saturation combination (F-110 Sand, {approx} 35% initial water saturation). In many of our tests we selected this combination intentionally to determine whether we could use a method to make the samples uniform. The following methods were examined: Excess gas, Freeze/thaw/form, Freeze/pressurize/thaw, Excess gas followed by water saturation, Excess water, Sand and kaolinite, Use of a nucleation enhancer (SnoMax), and Use of salt in the water. Below, each method, the underlying hypothesis, and our results are briefly presented, followed by a brief conclusion. Many of the hypotheses investigated are not our own, but were presented to us. Much of the data presented is from x-ray CT scanning our samples. The x-ray CT scanner provides a three-dimensional density map of our samples. From this map and the physics that is occurring in our samples, we are able to gain an understanding of the spatial nature of the processes that occur, and attribute them to the locations where they occur.

  18. Try-A Global Database of Plant Traits

    SciTech Connect (OSTI)

    Thornton, Peter E [ORNL

    2011-01-01

    Plant traits the morphological, anatomical, physiological, biochemical and phenological characteristics of plants and their organs determine how primary producers respond to environmental factors, affect other trophic levels, influence ecosystem processes and services and provide a link from species richness to ecosystem functional diversity. Trait data thus represent the raw material for a wide range of research from evolutionary biology, community and functional ecology to biogeography. Here we present the global database initiative named TRY, which has united a wide range of the plant trait research community worldwide and gained an unprecedented buy-in of trait data: so far 93 trait databases have been contributed. The data repository currently contains almost three million trait entries for 69 000 out of the world s 300 000 plant species, with a focus on 52 groups of traits characterizing the vegetative and regeneration stages of the plant life cycle, including growth, dispersal, establishment and persistence. A first data analysis shows that most plant traits are approximately log-normally distributed, with widely differing ranges of variation across traits. Most trait variation is between species (interspecific), but significant intraspecific variation is also documented, up to 40% of the overall variation. Plant functional types (PFTs), as commonly used in vegetation models, capture a substantial fraction of the observed variation but for several traits most variation occurs within PFTs, up to 75% of the overall variation. In the context of vegetation models these traits would better be represented by state variables rather than fixed parameter values. The improved availability of plant trait data in the unified global database is expected to support a paradigm shift from species to trait-based ecology, offer new opportunities for synthetic plant trait research and enable a more realistic and empirically grounded representation of terrestrial vegetation in Earth system models.

  19. Students try out high-tech equipment at ASM Materials Camp |...

    National Nuclear Security Administration (NNSA)

    try out high-tech equipment at ASM Materials Camp | National Nuclear Security Administration Facebook Twitter Youtube Flickr RSS People Mission Managing the Stockpile Preventing...

  20. Resonant Soft X-Ray Scattering of Tri-Block Copolymers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    biomolecular materials to structured electrolytes for lithum-ion batteries and supercapacitors. Drawings of 12 possible morphologies Varying morphologies of linear tri-block...

  1. Tri-Laboratory Linux Capacity Cluster 2007 SOW

    SciTech Connect (OSTI)

    Seager, M

    2007-03-22

    The Advanced Simulation and Computing (ASC) Program (formerly know as Accelerated Strategic Computing Initiative, ASCI) has led the world in capability computing for the last ten years. Capability computing is defined as a world-class platform (in the Top10 of the Top500.org list) with scientific simulations running at scale on the platform. Example systems are ASCI Red, Blue-Pacific, Blue-Mountain, White, Q, RedStorm, and Purple. ASC applications have scaled to multiple thousands of CPUs and accomplished a long list of mission milestones on these ASC capability platforms. However, the computing demands of the ASC and Stockpile Stewardship programs also include a vast number of smaller scale runs for day-to-day simulations. Indeed, every 'hero' capability run requires many hundreds to thousands of much smaller runs in preparation and post processing activities. In addition, there are many aspects of the Stockpile Stewardship Program (SSP) that can be directly accomplished with these so-called 'capacity' calculations. The need for capacity is now so great within the program that it is increasingly difficult to allocate the computer resources required by the larger capability runs. To rectify the current 'capacity' computing resource shortfall, the ASC program has allocated a large portion of the overall ASC platforms budget to 'capacity' systems. In addition, within the next five to ten years the Life Extension Programs (LEPs) for major nuclear weapons systems must be accomplished. These LEPs and other SSP programmatic elements will further drive the need for capacity calculations and hence 'capacity' systems as well as future ASC capability calculations on 'capability' systems. To respond to this new workload analysis, the ASC program will be making a large sustained strategic investment in these capacity systems over the next ten years, starting with the United States Government Fiscal Year 2007 (GFY07). However, given the growing need for 'capability' systems as well, the budget demands are extreme and new, more cost effective ways of fielding these systems must be developed. This Tri-Laboratory Linux Capacity Cluster (TLCC) procurement represents the ASC first investment vehicle in these capacity systems. It also represents a new strategy for quickly building, fielding and integrating many Linux clusters of various sizes into classified and unclassified production service through a concept of Scalable Units (SU). The programmatic objective is to dramatically reduce the overall Total Cost of Ownership (TCO) of these 'capacity' systems relative to the best practices in Linux Cluster deployments today. This objective only makes sense in the context of these systems quickly becoming very robust and useful production clusters under the crushing load that will be inflicted on them by the ASC and SSP scientific simulation capacity workload.

  2. IFT2015 Miklos Csuros 9 fevrier 2011 8 Algorithmes avec un tas : tri et fusion

    E-Print Network [OSTI]

    Csürös, Miklós

    IFT2015 Mikl´os Csur¨os 9 f´evrier 2011 8 Algorithmes avec un tas : tri et fusion 8.1 Tri par tas auxiliaire de taille n. 8.2 Fusion de listes multiples Algo MULTI-FUSION(A0[0..n0 - 1], . . . , Am-1[0..nm-1

  3. Color Space Conversion for MPEG decoding on FPGA-augmented TriMedia Processor

    E-Print Network [OSTI]

    Cotofana, Sorin

    the CSC unit on FPGA at application load-time, ¼ Ö- to-Ê ¼ ¼ ¼ color space conversion can be computedColor Space Conversion for MPEG decoding on FPGA-augmented TriMedia Processor Mihai SimaÝÞ Stamatis://ce.et.tudelft.nl/~mihai Abstract A case study on Color Space Conversion (CSC) for MPEG decoding, carried out on FPGA- augmented Tri

  4. arXiv:0801.0137v1[cond-mat.dis-nn]30Dec2007 Depinning in a two-layer model of plastic flow

    E-Print Network [OSTI]

    Wiese, Kay Jörg

    arXiv:0801.0137v1[cond-mat.dis-nn]30Dec2007 Depinning in a two-layer model of plastic flow Pierre a transition from elastic depinning to hysteretic plastic depinning as disorder or viscous coupling state and a pinned state below the elastic depinning threshold, with hysteretic plastic depinning

  5. AUTHORIZATION TO DISCLOSE AND USE INFORMATION FERPA, also known as the Buckley Amendment, is a federal law that gives students' some rights of privacy and dis-

    E-Print Network [OSTI]

    Alpay, S. Pamir

    AUTHORIZATION TO DISCLOSE AND USE INFORMATION FERPA, also known as the Buckley Amendment, is a federal law that gives students' some rights of privacy and dis- closure over the records and documents, the University may not disclose the information contained in student education records without a student

  6. arXiv:1002.4583v2[cond-mat.dis-nn]1May2010 Towards Google matrix of brain

    E-Print Network [OSTI]

    Shepelyansky, Dima

    arXiv:1002.4583v2[cond-mat.dis-nn]1May2010 Towards Google matrix of brain D.L.Shepelyansky1, 2 networks. The Google matrix G is constructed on the basis of neuronal network of a brain model discussed John von Neumann traced first parallels between architecture of the computer and the brain [1]. Since

  7. Prompt photons in photoproduction and DIS , Eric Brownson, U. Wisconsin Photon 2007, July 10, 2007 -1 Prompt Photons in Photoproduction and

    E-Print Network [OSTI]

    Prompt photons in photoproduction and DIS , Eric Brownson, U. Wisconsin Photon 2007, July 10, 2007 - 1 Prompt Photons in Photoproduction and Deep Inelastic Scattering at HERA Eric Brownson University of Wisconsin On behalf of the ZEUS & H1 Collaborations Photon 2007 Paris, France #12;Prompt photons

  8. Vacuum misalignment corrections to tri-bimaximal mixing and form dominance

    E-Print Network [OSTI]

    Stephen F. King

    2011-03-03

    Tri-bimaximal neutrino mixing may arise from see-saw models based on family symmetry which is spontaneously broken by flavons with particular vacuum alignments. However recent analyses hint that tri-bimaximal mixing may be insensitive to the precise form of vacuum alignment. In this paper we derive approximate analytic results which express the deviations from tri-bimaximal neutrino mixing due to vacuum misalignment. We also relate vacuum misalignment to departures from form dominance, corresponding to deviations from the real orthogonal $R$ matrix, where such corrections are necessary to allow for successful leptogenesis. The analytic results show that the corrections to tri-bimaximal mixing and form dominance depend on the pattern of the vacuum misalignment, with the two effects being uncorrelated.

  9. Exchange Reactions Between a Molten Salt and a Solution of Tri...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Exchange Reactions Between a Molten Salt and a Solution of Tri-Butyl Phosphate in a Liquid Silicone; REACTIONS D'ECHANGE ENTRE UN SEL FONDU ET UNE SOLUTION DE...

  10. Tri-County Electric Cooperative- Energy Efficient Water Heater Rebate Program

    Office of Energy Efficiency and Renewable Energy (EERE)

    Tri-County Electric Cooperative offers a $75 rebate on the purchase of energy-efficient electric water heaters. The rebate is valid for new or replacement units which have an Energy Factor Rating...

  11. CON'TRI BUTION TO THE BIOLOGY OF THE KING CRAB

    E-Print Network [OSTI]

    CON'TRI BUTION TO THE BIOLOGY OF THE KING CRAB ( Paralithodes eam t sehat iea Tilesius during moulting. Classifioat ion of speo iea . Weight of orabs · · · · · · · · ·and their distribution

  12. High Temperature Fuel Cell Tri-Generation of Power, Heat & H2...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heat & H2 from Biogas High Temperature Fuel Cell Tri-Generation of Power, Heat & H2 from Biogas Success story about using waste water treatment gas for hydrogen production at UC...

  13. Resonant Soft X-Ray Scattering of Tri-Block Copolymers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Tri-BCPs and multi-block BCPs are being considered for use in applications ranging from fuel-cell membranes to hybrid biomolecular materials to structured electrolytes for...

  14. Respiratory correlated cone beam CT

    SciTech Connect (OSTI)

    Sonke, Jan-Jakob; Zijp, Lambert; Remeijer, Peter; Herk, Marcel van [Department of Radiation Oncology, Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands)

    2005-04-01

    A cone beam computed tomography (CBCT) scanner integrated with a linear accelerator is a powerful tool for image guided radiotherapy. Respiratory motion, however, induces artifacts in CBCT, while the respiratory correlated procedures, developed to reduce motion artifacts in axial and helical CT are not suitable for such CBCT scanners. We have developed an alternative respiratory correlated procedure for CBCT and evaluated its performance. This respiratory correlated CBCT procedure consists of retrospective sorting in projection space, yielding subsets of projections that each corresponds to a certain breathing phase. Subsequently, these subsets are reconstructed into a four-dimensional (4D) CBCT dataset. The breathing signal, required for respiratory correlation, was directly extracted from the 2D projection data, removing the need for an additional respiratory monitor system. Due to the reduced number of projections per phase, the contrast-to-noise ratio in a 4D scan reduced by a factor 2.6-3.7 compared to a 3D scan based on all projections. Projection data of a spherical phantom moving with a 3 and 5 s period with and without simulated breathing irregularities were acquired and reconstructed into 3D and 4D CBCT datasets. The positional deviations of the phantoms center of gravity between 4D CBCT and fluoroscopy were small: 0.13{+-}0.09 mm for the regular motion and 0.39{+-}0.24 mm for the irregular motion. Motion artifacts, clearly present in the 3D CBCT datasets, were substantially reduced in the 4D datasets, even in the presence of breathing irregularities, such that the shape of the moving structures could be identified more accurately. Moreover, the 4D CBCT dataset provided information on the 3D trajectory of the moving structures, absent in the 3D data. Considerable breathing irregularities, however, substantially reduces the image quality. Data presented for three different lung cancer patients were in line with the results obtained from the phantom study. In conclusion, we have successfully implemented a respiratory correlated CBCT procedure yielding a 4D dataset. With respiratory correlated CBCT on a linear accelerator, the mean position, trajectory, and shape of a moving tumor can be verified just prior to treatment. Such verification reduces respiration induced geometrical uncertainties, enabling safe delivery of 4D radiotherapy such as gated radiotherapy with small margins.

  15. (Dis)ability and (dis)aster 

    E-Print Network [OSTI]

    Stough, Laura; Kelman, Ilan

    2015-01-01

    and Pothier, 2006; Oliver, 1986, 1996). Others argue that conceptualizing disability as completely social in nature overlooks or minimizes the corporeal experiences and physical sensations of people with 9781137485991_02_c01.indd 5 disabilities (see... and Disasters 31(3): 384–402. Van Willigen, M., T. Edwards, B. Edwards, and S. Hessee. 2002. Riding out the storm: Experiences of the physically disabled during Hurricanes Bonnie, Dennis, and Floyd. Natural Hazards Review 3(3): 98–106. Wisner, B., P...

  16. 263 Farmington Avenue, Farmington, CT 06030 Confidential Health Information Enclosed

    E-Print Network [OSTI]

    Oliver, Douglas L.

    263 Farmington Avenue, Farmington, CT 06030 Confidential Health Information Enclosed Sender Information: Date: ________________________________ Time: ________________________ From: ________________________ Recipient Information: To: ________________________________ Phone: ________________________ Organization

  17. PET/CT shielding design comparisons 

    E-Print Network [OSTI]

    Coker, Audra Lee

    2007-09-17

    used to calculate unattenuated radiation through existing lead walls. The computer code MCNPX was used to simulate the leaded walls of the PET/CT suite and provide another set of results. These two sets of results were compared to doses gathered from...

  18. 1 Put me not to rebuke O | Lord in thine | anger : neither | chasten me in thy | heavy dis | 2 For thine | arrows stick | fast in me : and | thy hand | presseth me | sore.

    E-Print Network [OSTI]

    Flynn, E. Victor

    Psalm 38 1 Put me not to rebuke O | Lord · in thine | anger : neither | chasten me · in thy | heavy There is no health in my flesh be | cause of · thy dis | pleasure : neither is there any rest in my | bones

  19. Hanford and the tri-cities economy: Review and outlook, March 1989

    SciTech Connect (OSTI)

    Scott, M.J.; Belzer, D.B.; March, S.J.; Beck, D.M.; Schultz, R.W.; Harkreader, S.A.

    1989-03-01

    The economy of the Tri-Cities, Washington area (primarily, Benton and Franklin Counties) is in transition due to major changes in two Department of Energy programs at Hanford---the abrupt ending of the Basalt Waste Isolation Project (BWIP) in December 1987 and the placing of the N Reactor in ''cold standby'' status in February 1988. This report reviews the economic situation in the Tri-Cities during 1988 and presents forecasts for key economic indicators for 1989. This report will be updated about every six months to review the changes in the area economy and forecast the near-term outlook. 6 figs., 33 tabs.

  20. Hanford and the Tri-Cities Economy: Historical Trends 1970-2008

    SciTech Connect (OSTI)

    Fowler, Richard A.; Scott, Michael J.

    2009-10-01

    This white paper examines the effect that the Hanford Site has had on the Tri-Cities economy from 1970-2008. Total area employment levels, population, and the real estate market are compared to DOE contractor employment and funding levels, which tended to follow each other until the mid-1990s. Since 1994, area employment, total incomes, population and the real estate market have increased significantly despite very little changes in Hanford employment levels. The data indicate that in recent history, the Tri-Cities economy has become increasingly independent of Hanford.

  1. Tri-Party Agreement U.S. Department of Energy Washington State Department of Ecology

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With U.S.WeekProducts[TRI-PARTY AGREEMENT AGENCIES - PUBLIC7 Tri-Party

  2. Implications of CT noise and artifacts for quantitative {sup 99m}Tc SPECT/CT imaging

    SciTech Connect (OSTI)

    Hulme, K. W.; Kappadath, S. C.

    2014-04-15

    Purpose: This paper evaluates the effects of computed tomography (CT) image noise and artifacts on quantitative single-photon emission computed-tomography (SPECT) imaging, with the aim of establishing an appropriate range of CT acquisition parameters for low-dose protocols with respect to accurate SPECT attenuation correction (AC). Methods: SPECT images of two geometric and one anthropomorphic phantom were reconstructed iteratively using CT scans acquired at a range of dose levels (CTDI{sub vol} = 0.4 to 46 mGy). Resultant SPECT image quality was evaluated by comparing mean signal, background noise, and artifacts to SPECT images reconstructed using the highest dose CT for AC. Noise injection was performed on linear-attenuation (?) maps to determine the CT noise threshold for accurate AC. Results: High levels of CT noise (? ? 200–400 HU) resulted in low ?-maps noise (? ? 1%–3%). Noise levels greater than ?10% in 140 keV ?-maps were required to produce visibly perceptible increases of ?15% in {sup 99m}Tc SPECT images. These noise levels would be achieved at low CT dose levels (CTDI{sub vol} = 4 ?Gy) that are over 2 orders of magnitude lower than the minimum dose for diagnostic CT scanners. CT noise could also lower (bias) the expected ? values. The relative error in reconstructed SPECT signal trended linearly with the relative shift in ?. SPECT signal was, on average, underestimated in regions corresponding with beam-hardening artifacts in CT images. Any process that has the potential to change the CT number of a region by ?100 HU (e.g., misregistration between CT images and SPECT images due to motion, the presence of contrast in CT images) could introduce errors in ?{sub 140} {sub keV} on the order of 10%, that in turn, could introduce errors on the order of ?10% into the reconstructed {sup 99m}Tc SPECT image. Conclusions: The impact of CT noise on SPECT noise was demonstrated to be negligible for clinically achievable CT parameters. Because CT dose levels that affect SPECT quantification is low (CTDI{sub vol} ? 4 ?Gy), the low dose limit for the CT exam as part of SPECT/CT will be guided by CT image quality requirements for anatomical localization and artifact reduction. A CT technique with higher kVp in combination with lower mAs is recommended when low-dose CT images are used for AC to minimize beam-hardening artifacts.

  3. How to search resources If you are looking for an article, try

    E-Print Network [OSTI]

    McPhee-Shaw, Erika

    or journal title within the library holdings. 3) Search for the source (i.e. journal title) by entering all/any of your search terms. Click `GO'. #12;Browse Search: 1) To browse the catalog clickHow to search resources If you are looking for an article, try: Google Scholar: This search engine

  4. CEMP-EC 13 February 1995 TRI-SERVICE MILITARY CONSTRUCTION PROGRAM (MCP) INDEX

    E-Print Network [OSTI]

    US Army Corps of Engineers

    CEMP-EC 13 February 1995 TABLE IV TRI-SERVICE MILITARY CONSTRUCTION PROGRAM (MCP) INDEX FOR FY 1996 ------------- 1893 1 JUL 1994 ------------- 1908 2.6% 1 OCT 1994 ------------- 1923 --------------- 1 JAN 1995 ------------- 1937 FY 1995 1 APR 1995 ------------- 1945 1 JUL 1995 ------------- 1962 2.9% 1 OCT 1995

  5. Analysis of a Third-Generation Princeton Tri-leaflet Mechanical Heart Valve

    E-Print Network [OSTI]

    Petta, Jason

    Analysis of a Third-Generation Princeton Tri-leaflet Mechanical Heart Valve Michael Hsu Advisor heart valve · Static analysis of leaflet under uniform pressure of 10 MPa Summer Objectives · Find Heart valve disease · Over 5 million affected · Over 225,000 valve- replacement surgeries performed

  6. Targeted Support Program Attracting outside businesses to the Tri-City region with free service

    E-Print Network [OSTI]

    to the community. Jobs must pay "family wages" of $39,000 or more annually to qualify. A participating company also Washington's Tri- Cities region. Once the company announces its plans to move, the TSP may provide in proportion to the number of jobs created. · Jobs targeted: Permanent, full-time, family-wage ($39K or more

  7. Siemens Corporate Technology CT | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-Enhancing Capacity for LowInformationShoshone County,SiCorporate Technology CT

  8. Tri-material multilayer coatings with high reflectivity and wide bandwidth for 25 to 50 nm extreme ultraviolet light

    E-Print Network [OSTI]

    Aquila, Andrew

    2010-01-01

    and testing ofEUV multilayer coatings for the AtmosphericTri-material multilayer coatings with high reflectivity andthe bandwidth of multilayer coatings. The simplest method to

  9. My Generation--The Who People try to put us d-down

    E-Print Network [OSTI]

    Reiners, Peter W.

    My Generation--The Who Intro: G F People try to put us d-down G F G(once) Talkin' 'bout my generation Just because we get around G F G(once) Talkin' 'bout my generation Things they do look awful cold G F G(once) Talkin' 'bout my generation I hope I die before I get old G F G(once) Talkin' 'bout my

  10. Segmentation of artifacts and anatomy in CT metal artifact reduction

    E-Print Network [OSTI]

    Karimi, Seemeen; Cosman, Pamela; Wald, Christoph; Martz, Harry

    2012-01-01

    Maximum- likelihood dual-energy tomographic imageartifact reduction by dual energy CT using monoenergetictive reconstruction of dual energy data 21 has the potential

  11. Diffusion and Catalytic Cracking of 1,3,5 Tri-iso-propyl-benzene in FCC Catalysts

    E-Print Network [OSTI]

    Al-Khattaf, Sulaiman

    1 Diffusion and Catalytic Cracking of 1,3,5 Tri-iso- propyl-benzene in FCC Catalysts S.Al-Khattaf1 describes catalytic cracking experiments developed in a novel CREC Riser Simulator using 1,3,5-Tri-iso-propyl-benzene

  12. CT. L-2 United States Government

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth DakotaRobbins and Myers Co -VANaval ,, *' ;x-L* d! CT NC0 - i ,

  13. CT Investment Partners LLP | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoopButte County, California: Energy ResourcesCRED: A New Model of ClimateOpenCT

  14. Coronary CT angiography offers further risk stratification in the management of patients with normal SPECT results

    E-Print Network [OSTI]

    Budoff, Matthew J.; Hacioglu, Yalcin

    2010-01-01

    Coronary CT angiography offers further risk strati?cation inCoronary CT angiography offers further risk strati?cationCoronary CT angiography offers further risk strati?cation

  15. Lung Segmentation from CT with Severe Pathologies Using Anatomical Constraints

    E-Print Network [OSTI]

    Lung Segmentation from CT with Severe Pathologies Using Anatomical Constraints Neil Birkbeck Healthcare, Oxford, UK Abstract. The diversity in appearance of diseased lung tissue makes automatic segmentation of lungs from CT with severe pathologies chal- lenging. To overcome this challenge, we rely

  16. Automatic Labeling and Segmentation of Vertebrae in CT Images

    E-Print Network [OSTI]

    Freitas, Nando de

    vertebral column. I validate my technique in terms of accuracy of the labeling and segmentation of CT images handled labeling of the vertebral column in arbitrary scans [3, 4]. Klinder et al. build a template (mean(s) Affiliation Address email Abstract Detection, Labeling, and segmentation of the spinal column from CT images

  17. MicroCT: Semi-Automated Analysis of CT Reconstructed Data of Home Made Explosive Materials Using the Matlab MicroCT Analysis GUI

    SciTech Connect (OSTI)

    Seetho, I M; Brown, W D; Kallman, J S; Martz, H E; White, W T

    2011-09-22

    This Standard Operating Procedure (SOP) provides the specific procedural steps for analyzing reconstructed CT images obtained under the IDD Standard Operating Procedures for data acquisition [1] and MicroCT image reconstruction [2], per the IDD Quality Assurance Plan for MicroCT Scanning [3]. Although intended to apply primarily to MicroCT data acquired in the HEAFCAT Facility at LLNL, these procedures may also be applied to data acquired at Tyndall from the YXLON cabinet and at TSL from the HEXCAT system. This SOP also provides the procedural steps for preparing the tables and graphs to be used in the reporting of analytical results. This SOP applies to R and D work - for production applications, use [4].

  18. MicroCT: Automated Analysis of CT Reconstructed Data of Home Made Explosive Materials Using the Matlab MicroCT Analysis GUI

    SciTech Connect (OSTI)

    Seetho, I M; Brown, W D; Kallman, J S; Martz, H E; White, W T

    2011-09-22

    This Standard Operating Procedure (SOP) provides the specific procedural steps for analyzing reconstructed CT images obtained under the IDD Standard Operating Procedures for data acquisition [1] and MicroCT image reconstruction [2], per the IDD Quality Assurance Plan for MicroCT Scanning [3]. Although intended to apply primarily to MicroCT data acquired in the HEAFCAT Facility at LLNL, these procedures may also be applied to data acquired at Tyndall from the YXLON cabinet and at TSL from the HEXCAT system. This SOP also provides the procedural steps for preparing the tables and graphs to be used in the reporting of analytical results. This SOP applies to production work - for R and D there are two other semi-automated methods as given in [4, 5].

  19. Multi-energy CT Based on a Prior Rank, Intensity and Sparsity Model (PRISM)

    E-Print Network [OSTI]

    Soatto, Stefano

    -color, as a natural extension of dual energy CT [1], the future of CT will be multi-energy, generating much richer

  20. Parametrization of lepton mixing matrix in terms of deviations from bi-maximal and tri-bimaximl mixing

    E-Print Network [OSTI]

    Chandan Duarah; K. Sashikanta Singh; N. Nimai Singh

    2015-03-26

    We parametrize lepton mixing matrix, known as PMNS matrix, in terms of three parameters which account deviations of three mixing angles from their bi-maximal or tri-bimaximal values. On the basis of this parametrization we can determine corresponding charged lepton mixing matrix in terms of those three parameters which can deviate bi-maximal or tri-bimaximal mixing. We find that the charged lepton mixing matrices which can deviate bi-maximal mixing matrix and tri-bimaximal mixing matrix exhibit similar structures. Numerical analysis shows that these charged lepton mixing matrices are close to CKM matrix of quark sector.

  1. Tri-State G & T Assn, Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEt Al., 2013)OpenEnergyTrail CanyonsourceRiver Solar |TrexaTri-State

  2. 1-nm-thick graphene tri-layer as the ultimate copper diffusion barrier

    SciTech Connect (OSTI)

    Nguyen, Ba-Son [Department of Mechanical Engineering, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan (China); Lin, Jen-Fin [Department of Mechanical Engineering, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan (China); Center for Micro/Nano Science and Technology, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan (China); Perng, Dung-Ching, E-mail: dcperng@ee.ncku.edu.tw [Institute of Microelectronics and Electrical Engineering Department, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan (China); Center for Micro/Nano Science and Technology, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan (China)

    2014-02-24

    We demonstrate the thinnest ever reported Cu diffusion barrier, a 1-nm-thick graphene tri-layer. X-ray diffraction patterns and Raman spectra show that the graphene is thermally stable at up to 750?°C against Cu diffusion. Transmission electron microscopy images show that there was no inter-diffusion in the Cu/graphene/Si structure. Raman analyses indicate that the graphene may have degraded into a nanocrystalline structure at 750?°C. At 800?°C, the perfect carbon structure was damaged, and thus the barrier failed. The results of this study suggest that graphene could be the ultimate Cu interconnect diffusion barrier.

  3. Tri-Party Agreement Agencies - Public involvement calendar - fiscal year 2015

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With U.S.WeekProducts[TRI-PARTY AGREEMENT AGENCIES - PUBLIC

  4. Production and trapping of radioactive atoms at the TRI\\muP facility

    E-Print Network [OSTI]

    E. Traykov; U. Dammalapati; S. De; O. C. Dermois; L. Huisman; K. Jungmann; W. Kruithof; A. J. Mol; C. J. G. Onderwater; A. Rogachevskiy; M. da Silva e Silva; M. Sohani; O. Versolato; L. Willmann; H. W. Wilschut

    2008-03-28

    The structures for the TRI$\\mu$P facility have been completed and commissioned. At the facility radioactive nuclides are produced to study fundamental interactions and symmetries. An important feature is the possibility to trap radioactive atoms in order to obtain and hold a pure substrate-free sample for precision measurements. In the TRI$\\mu$P facility a production target is followed by a magnetic separator, where radioactive isotopes are produced in inverse reaction kinematics. Separation up to 99.95% could be achieved for $^{21}$Na. A novel transmitting thermal ionizing device was developed to stop the energetic isotopes. Some 50% of stopped $^{21}$Na could be extracted and transported as low energy singly charged ions into a radio frequency quadrupole cooler and buncher with 35% transmission efficiency. The ions are transported lossless via a drift tube and a low energy electrostatic beam line into the experimental setup. Such ions can be neutralized on hot metal foils and the resulting atoms can be stored in a magneto-optical trap. The functioning of that principle was demonstrated with stable Na extracted from the thermal ionizer, radioactive beams will follow next.

  5. Webinar: 2011-2012 Hydrogen Student Design Contest Winners: On-Campus Tri-Generation Fuel Cell Systems

    Broader source: Energy.gov [DOE]

    Video recording of the Fuel Cell Technologies Office webinar, 2011-2012 Hydrogen Student Design Contest Winners: On-Campus Tri-Generation Fuel Cell Systems, originally presented on September 4, 2012.

  6. Tri-City Herald OpEd: Electric Vehicles are a smart choice

    SciTech Connect (OSTI)

    Christensen, Peter C.; Haas, Anne M.

    2010-12-10

    Why are so many of us at the Pacific Northwest National Laboratory, a national thought leader in power industry issues located right here in the Tri-Cities, so bullish on the future of EVs? And why do we think it's so important that this country, especially THIS part of the country, be leaders in the adoption of EVs? Is it that we all just happen to like driving polluting golf carts? The answer is that, like most everyone else, most of us here at PNNL drive to work every day, and like most people, we care about the cost of gasoline and the impact that burning imported oil has on the environment and on our foreign policy. The reality is that electric vehicles are simply more efficient, pollute much less, use locally-generated energy, and cost MUCH less to drive.

  7. Auto-DR and Pre-cooling of Buildings at Tri-City Corporate Center

    SciTech Connect (OSTI)

    Yin, Rongxin; Xu, Peng; Kiliccote, Sila

    2008-11-01

    Over the several past years, Lawrence Berkeley National Laboratory (LBNL) has conducted field tests for different pre-cooling strategies in different commercial buildings within California. The test results indicated that pre-cooling strategies were effective in reducing electric demand in these buildings during peak periods. This project studied how to optimize pre-cooling strategies for eleven buildings in the Tri-City Corporate Center, San Bernardino, California with the assistance of a building energy simulation tool -- the Demand Response Quick Assessment Tool (DRQAT) developed by LBNL's Demand Response Research Center funded by the California Energy Commission's Public Interest Energy Research (PIER) Program. From the simulation results of these eleven buildings, optimal pre-cooling and temperature reset strategies were developed. The study shows that after refining and calibrating initial models with measured data, the accuracy of the models can be greatly improved and the models can be used to predict load reductions for automated demand response (Auto-DR) events. This study summarizes the optimization experience of the procedure to develop and calibrate building models in DRQAT. In order to confirm the actual effect of demand response strategies, the simulation results were compared to the field test data. The results indicated that the optimal demand response strategies worked well for all buildings in the Tri-City Corporate Center. This study also compares DRQAT with other building energy simulation tools (eQUEST and BEST). The comparison indicate that eQUEST and BEST underestimate the actual demand shed of the pre-cooling strategies due to a flaw in DOE2's simulation engine for treating wall thermal mass. DRQAT is a more accurate tool in predicting thermal mass effects of DR events.

  8. CT reconstruction techniques for improved accuracy of lung CT airway measurement

    SciTech Connect (OSTI)

    Rodriguez, A.; Ranallo, F. N.; Judy, P. F.; Gierada, D. S.; Fain, S. B.

    2014-11-01

    Purpose: To determine the impact of constrained reconstruction techniques on quantitative CT (qCT) of the lung parenchyma and airways for low x-ray radiation dose. Methods: Measurement of small airways with qCT remains a challenge, especially for low x-ray dose protocols. Images of the COPDGene quality assurance phantom (CTP698, The Phantom Laboratory, Salem, NY) were obtained using a GE discovery CT750 HD scanner for helical scans at x-ray radiation dose-equivalents ranging from 1 to 4.12 mSv (12–100 mA s current–time product). Other parameters were 40 mm collimation, 0.984 pitch, 0.5 s rotation, and 0.625 mm thickness. The phantom was sandwiched between 7.5 cm thick water attenuating phantoms for a total length of 20 cm to better simulate the scatter conditions of patient scans. Image data sets were reconstructed using STANDARD (STD), DETAIL, BONE, and EDGE algorithms for filtered back projection (FBP), 100% adaptive statistical iterative reconstruction (ASIR), and Veo reconstructions. Reduced (half) display field of view (DFOV) was used to increase sampling across airway phantom structures. Inner diameter (ID), wall area percent (WA%), and wall thickness (WT) measurements of eight airway mimicking tubes in the phantom, including a 2.5 mm ID (42.6 WA%, 0.4 mm WT), 3 mm ID (49.0 WA%, 0.6 mm WT), and 6 mm ID (49.0 WA%, 1.2 mm WT) were performed with Airway Inspector (Surgical Planning Laboratory, Brigham and Women’s Hospital, Boston, MA) using the phase congruency edge detection method. The average of individual measures at five central slices of the phantom was taken to reduce measurement error. Results: WA% measures were greatly overestimated while IDs were underestimated for the smaller airways, especially for reconstructions at full DFOV (36 cm) using the STD kernel, due to poor sampling and spatial resolution (0.7 mm pixel size). Despite low radiation dose, the ID of the 6 mm ID airway was consistently measured accurately for all methods other than STD FBP. Veo reconstructions showed slight improvement over STD FBP reconstructions (4%–9% increase in accuracy). The most improved ID and WA% measures were for the smaller airways, especially for low dose scans reconstructed at half DFOV (18 cm) with the EDGE algorithm in combination with 100% ASIR to mitigate noise. Using the BONE + ASIR at half BONE technique, measures improved by a factor of 2 over STD FBP even at a quarter of the x-ray dose. Conclusions: The flexibility of ASIR in combination with higher frequency algorithms, such as BONE, provided the greatest accuracy for conventional and low x-ray dose relative to FBP. Veo provided more modest improvement in qCT measures, likely due to its compatibility only with the smoother STD kernel.

  9. Weather data for simplified energy calculation methods. Volume II. Middle United States: TRY data

    SciTech Connect (OSTI)

    Olsen, A.R.; Moreno, S.; Deringer, J.; Watson, C.R.

    1984-08-01

    The objective of this report is to provide a source of weather data for direct use with a number of simplified energy calculation methods available today. Complete weather data for a number of cities in the United States are provided for use in the following methods: degree hour, modified degree hour, bin, modified bin, and variable degree day. This report contains sets of weather data for 22 cities in the continental United States using Test Reference Year (TRY) source weather data. The weather data at each city has been summarized in a number of ways to provide differing levels of detail necessary for alternative simplified energy calculation methods. Weather variables summarized include dry bulb and wet bulb temperature, percent relative humidity, humidity ratio, wind speed, percent possible sunshine, percent diffuse solar radiation, total solar radiation on horizontal and vertical surfaces, and solar heat gain through standard DSA glass. Monthly and annual summaries, in some cases by time of day, are available. These summaries are produced in a series of nine computer generated tables.

  10. Realistic simulation of reduced-dose CT with noise modeling and sinogram synthesis using DICOM CT images

    SciTech Connect (OSTI)

    Won Kim, Chang; Kim, Jong Hyo

    2014-01-15

    Purpose: Reducing the patient dose while maintaining the diagnostic image quality during CT exams is the subject of a growing number of studies, in which simulations of reduced-dose CT with patient data have been used as an effective technique when exploring the potential of various dose reduction techniques. Difficulties in accessing raw sinogram data, however, have restricted the use of this technique to a limited number of institutions. Here, we present a novel reduced-dose CT simulation technique which provides realistic low-dose images without the requirement of raw sinogram data. Methods: Two key characteristics of CT systems, the noise equivalent quanta (NEQ) and the algorithmic modulation transfer function (MTF), were measured for various combinations of object attenuation and tube currents by analyzing the noise power spectrum (NPS) of CT images obtained with a set of phantoms. Those measurements were used to develop a comprehensive CT noise model covering the reduced x-ray photon flux, object attenuation, system noise, and bow-tie filter, which was then employed to generate a simulated noise sinogram for the reduced-dose condition with the use of a synthetic sinogram generated from a reference CT image. The simulated noise sinogram was filtered with the algorithmic MTF and back-projected to create a noise CT image, which was then added to the reference CT image, finally providing a simulated reduced-dose CT image. The simulation performance was evaluated in terms of the degree of NPS similarity, the noise magnitude, the bow-tie filter effect, and the streak noise pattern at photon starvation sites with the set of phantom images. Results: The simulation results showed good agreement with actual low-dose CT images in terms of their visual appearance and in a quantitative evaluation test. The magnitude and shape of the NPS curves of the simulated low-dose images agreed well with those of real low-dose images, showing discrepancies of less than +/?3.2% in terms of the noise power at the peak height and +/?1.2% in terms of the spatial frequency at the peak height. The magnitudes of the noise measured for 12 different combinations the phantom size, tube current, and reconstruction kernel for the simulated and real low-dose images were very similar, with differences of 0.1 to 4.7%. Thep value for a statistical testing of the difference in the noise magnitude ranged from 0.99 to 0.11, showing that there was no difference statistically between the noise magnitudes of the real and simulated low-dose images using our method. The strength and pattern of the streak noise in an anthropomorphic phantom was also consistent with expectations. Conclusions: A novel reduced-dose CT simulation technique was developed which uses only CT images while not requiring raw sinogram data. Our method can provide realistic simulation results under reduced-dose conditions both in terms of the noise magnitude and the textual appearance. This technique has the potential to promote clinical research for patient dose reductions.

  11. The sequence and characterization of TRI1, a cytochrome P450 monooxygenase involved in T-2 toxin biosynthesis 

    E-Print Network [OSTI]

    Meek, Isaac Burton

    2001-01-01

    of C8 during T-2 toxin biosynthesis (6). TRI1 cDNA clones were identified during a differential hybridization screen of a cDNA library (A. W. Peplow, A. G. Tag, G. F. Garifullina, and M. N. Beremand, unpublished). Comparative analysis between...

  12. Research Risk Assessment Guidelines Research projects that meet the Tri-Council definition of minimal risk are eligible for delegated

    E-Print Network [OSTI]

    Northern British Columbia, University of

    1 Research Risk Assessment Guidelines Research projects that meet the Tri-Council definition Member and the Chair of the Research Ethics Board (REB). To help determine whether your research project: Ethical Conduct of Research Involving Humans, chapter 2, part b. Definition of Minimal Risk According

  13. Waste management Stockholm University tries to maintain its environmental certification and we would be happy if you

    E-Print Network [OSTI]

    Wohlfarth, Barbara

    containers in the garbage-room. The remnants in your waste-paper-baskets could be food remnants, fruit peelWaste management Stockholm University tries to maintain its environmental certification and we for new products All waste-paper-baskets in your rooms, the kitchen and the copying

  14. A Compact Torus Fusion Reactor Utilizing a Continuously Generated Strings of CT's. The CT String Reactor, CTSR.

    SciTech Connect (OSTI)

    Hartman, C W; Reisman, D B; McLean, H S; Thomas, J

    2007-05-30

    A fusion reactor is described in which a moving string of mutually repelling compact toruses (alternating helicity, unidirectional Btheta) is generated by repetitive injection using a magnetized coaxial gun driven by continuous gun current with alternating poloidal field. An injected CT relaxes to a minimum magnetic energy equilibrium, moves into a compression cone, and enters a conducting cylinder where the plasma is heated to fusion-producing temperature. The CT then passes into a blanketed region where fusion energy is produced and, on emergence from the fusion region, the CT undergoes controlled expansion in an exit cone where an alternating poloidal field opens the flux surfaces to directly recover the CT magnetic energy as current which is returned to the formation gun. The CT String Reactor (CTSTR) reactor satisfies all the necessary MHD stability requirements and is based on extrapolation of experimentally achieved formation, stability, and plasma confinement. It is supported by extensive 2D, MHD calculations. CTSTR employs minimal external fields supplied by normal conductors, and can produce high fusion power density with uniform wall loading. The geometric simplicity of CTSTR acts to minimize initial and maintenance costs, including periodic replacement of the reactor first wall.

  15. Tri-Lateral Noor al Salaam High Concentration Solar Central Receiver Program

    SciTech Connect (OSTI)

    Blackmon, James B

    2008-03-31

    This report documents the efforts conducted primarily under the Noor al Salaam (“Light of Peace”) program under DOE GRANT NUMBER DE-FC36-02GO12030, together with relevant technical results from a closely related technology development effort, the U.S./Israel Science and Technology Foundation (USISTF) High Concentration Solar Central Receiver program. These efforts involved preliminary design, development, and test of selected prototype power production subsystems and documentation of an initial version of the system definition for a high concentration solar hybrid/gas electrical power plant to be built in Zaafarana, Egypt as a first step in planned commercialization. A major part of the planned work was halted in 2007 with an amendment in October 2007 requiring that we complete the technical effort by December 31, 2007 and provide a final report to DOE within the following 90 days. This document summarizes the work conducted. The USISTF program was a 50/50 cost-shared program supported by the Department of Commerce through the U.S./Israel Science and Technology Commission (USISTC). The USISTC was cooperatively developed by President Clinton and the late Prime Minister Rabin of Israel "to encourage technological collaboration" and "support peace in the Middle East through economic development". The program was conducted as a follow-on effort to Israel's Magnet/CONSOLAR Program, which was an advanced development effort to design, fabricate, and test a solar central receiver and secondary optics for a "beam down" central receiver concept. The status of these hardware development programs is reviewed, since they form the basis for the Noor al Salaam program. Descriptions are provided of the integrated system and the major subsystems, including the heliostat, the high temperature air receiver, the power conversion unit, tower and tower reflector, compound parabolic concentrator, and the master control system. One objective of the USISTF program was to conduct marketing research, identify opportunities for use of this technology, and to the extent possible, secure an agreement leading to a pre-commercialization demonstration or prototype plant. This was accomplished with the agreement to conduct the Noor al Salaam program as a tri-lateral project between Egypt, Israel, and the U.S. The tri-lateral project was led by the University of Alabama in Huntsville (UAH); this included the Egyptian New and Renewable Energy Authority and the Israeli USISTC participants. This project, known was Noor al Salaam, was funded by the U.S. Agency for International Development (USAID) through the Department of Energy (DOE). The Egyptian activity was under the auspices of the Egyptian Ministry of Energy and Electricity, New and Renewable Energy Authority (NREA) as part of Egypt's plans for renewable energy development. The objective of the Noor al Salaam project was to develop the conditions necessary to obtain funding and construct and operate an approximately 10 to 20 Megawatt hybrid solar/natural gas demonstration power plant in Zaafarana, Egypt that could serve both as a test bed for advanced solar technology evaluations, and as a forerunner to commercial plant designs. This plant, termed Noor Al Salaam, or “Light of Peace”, reached the initial phase of system definition before being curtailed, in part by changes in USAID objectives, coupled with various delays that were beyond the scope of the program to resolve. The background of the USISTF technology development and pre-commercialization effort is provided in this report, together with documentation of the technology developments conducted under the Noor al Salaam program. It should be noted that only a relatively small part of the Noor al Salaam funding was expended over the approximately five years for which UAH was prime contractor before the program was ordered closed (Reference 1) so that the remaining funds could be returned to USAID.

  16. Probing the electronic stablility of multiply charged anions:sulfonated pyrene tri- and tetraanions

    SciTech Connect (OSTI)

    Wang, Xue B.; Sergeeva, Alina P.; Xing, Xiaopeng; massaouti, Maria; karpuschkin, tatjana; Hampe, Oliver; Boldyrev, Alexander I.; Kappes, Manfred M.; Wang, Lai S.

    2009-07-22

    The strong intramolecular Coulomb repulsion in multiply charged anions (MCAs) creates a potential barrier that provides dynamic stability to MCAs and allows electronically metastable species to be observed. The 1-hydroxy-3,6,8-pyrene-trisulfonate {[Py(OH)(SO3)3]3- or HPTS3-} was recently observed as a long-lived metastable MCA with a large negative electron binding energy of -0.66 eV. Here we use Penning trap mass spectrometry to monitor the spontaneous decay of HPTS3- f HPTS•2- + e- and have determined the half-life of HPTS3- to be 0.1 s. To explore the limit of electronic metastability, we tried to make the related quadruply charged pyrene-1,3,6,8-tetrasulfonate {[Py(SO3)4]4-}. However, only its decay product, the triply charged radical anion [Py(SO3)4]•3-, as well as the triply charged ion-pairs [Py(SO3)4H]3- and [Py(SO3)4Na]3-, was observed, suggesting that the tremendous intramolecular Coulomb repulsion makes the [Py(SO3)4]4- anion extremely short-lived. Photoelectron spectroscopy data showed that [Py(SO3)4]•3- is an electronically stable species with electron binding energies of +0.5 eV, whereas [Py(SO3)4H]3- and [Py(SO3)4Na]3- possess electron binding energies of 0.0 and -0.1 eV, respectively. Ab initio calculations confirmed the stability of these triply charged species and further predicted a large negative electron binding energy (-2.78 eV) for [Py(SO3)4]4-, consistent with its short lifetime

  17. Tri (2-chloroisopropyl) phosphate--an unexpected organochlorine contaminant in some charcoal air-sampling sorbent tubes

    SciTech Connect (OSTI)

    van Netten, C.; Brands, R.; Park, J.; Deverall, R. (Department of Health Care and Epidemiology, University of British Columbia, Vancouver, (Canada))

    1991-09-01

    Air sampling in a government building was necessary in response to reports of a cancer cluster. SKC (Eighty Four, Pa.) charcoal coconut shell-based sorbent tubes (226-01 lot 120) were recommended for this procedure. A recently purchased supply was present at the University of British Columbia and consequently was used for this particular study. Analysis of the front charcoal section showed the presence of a flame retardant, tri (2-chloroisopropyl) phosphate, which was confirmed by gas liquid chromatography (GLC) and mass spectrometry analysis. In an effort to identify the source of this fire retardant in the building, it became apparent from the analysis done on unknown field blanks that tri (2-chloroisopropyl) phosphate was a contaminant of the sorbent tubes used. Analysis of additional blank tubes identified the foam separators as the most likely source of contamination. Levels of tri (2-chloroisopropyl) phosphate in the front charcoal section ranged from 1.3 to 5.9 micrograms. The foam separator contained between 11.4 and 16.5 micrograms, and the backup charcoal section contained between 14.5 and 24.0 micrograms of tri (2-chloroisopropyl) phosphate. In addition, another flame retardant, tri (1,3 dichloro-2-propyl) phosphate was also found. Because these contaminants have long column retention times in GLC, it may not be apparent that these contaminants are present and consequently are likely to have modified the sorbent characteristics of the activated charcoal. Another batch of sorbent tubes bearing the same catalog number and lot number was purchased from the supplier; no flame retardants were found in this batch.

  18. JID:PLREV AID:576 /DIS [m3SC+; v1.201; Prn:27/01/2015; 14:54] P.1 (1-2) Available online at www.sciencedirect.com

    E-Print Network [OSTI]

    Hamilton, Antonia

    JID:PLREV AID:576 /DIS [m3SC+; v1.201; Prn:27/01/2015; 14:54] P.1 (1-2) Available online at www needed to grasp an apple are defined by the shape of the goal (an apple tends to be a large sphere.201; Prn:27/01/2015; 14:54] P.2 (1-2) 2 A.F. de C. Hamilton / Physics of Life Reviews

  19. Automatic CT simulation optimization for radiation therapy: A general strategy

    SciTech Connect (OSTI)

    Li, Hua, E-mail: huli@radonc.wustl.edu; Chen, Hsin-Chen; Tan, Jun; Gay, Hiram; Michalski, Jeff M.; Mutic, Sasa [Department of Radiation Oncology, Washington University, St. Louis, Missouri 63110 (United States)] [Department of Radiation Oncology, Washington University, St. Louis, Missouri 63110 (United States); Yu, Lifeng [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States)] [Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905 (United States); Anastasio, Mark A. [Department of Biomedical Engineering, Washington University, St. Louis, Missouri 63110 (United States)] [Department of Biomedical Engineering, Washington University, St. Louis, Missouri 63110 (United States); Low, Daniel A. [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California 90095 (United States)] [Department of Radiation Oncology, University of California Los Angeles, Los Angeles, California 90095 (United States)

    2014-03-15

    Purpose: In radiation therapy, x-ray computed tomography (CT) simulation protocol specifications should be driven by the treatment planning requirements in lieu of duplicating diagnostic CT screening protocols. The purpose of this study was to develop a general strategy that allows for automatically, prospectively, and objectively determining the optimal patient-specific CT simulation protocols based on radiation-therapy goals, namely, maintenance of contouring quality and integrity while minimizing patient CT simulation dose. Methods: The authors proposed a general prediction strategy that provides automatic optimal CT simulation protocol selection as a function of patient size and treatment planning task. The optimal protocol is the one that delivers the minimum dose required to provide a CT simulation scan that yields accurate contours. Accurate treatment plans depend on accurate contours in order to conform the dose to actual tumor and normal organ positions. An image quality index, defined to characterize how simulation scan quality affects contour delineation, was developed and used to benchmark the contouring accuracy and treatment plan quality within the predication strategy. A clinical workflow was developed to select the optimal CT simulation protocols incorporating patient size, target delineation, and radiation dose efficiency. An experimental study using an anthropomorphic pelvis phantom with added-bolus layers was used to demonstrate how the proposed prediction strategy could be implemented and how the optimal CT simulation protocols could be selected for prostate cancer patients based on patient size and treatment planning task. Clinical IMRT prostate treatment plans for seven CT scans with varied image quality indices were separately optimized and compared to verify the trace of target and organ dosimetry coverage. Results: Based on the phantom study, the optimal image quality index for accurate manual prostate contouring was 4.4. The optimal tube potentials for patient sizes of 38, 43, 48, 53, and 58 cm were 120, 140, 140, 140, and 140 kVp, respectively, and the corresponding minimum CTDIvol for achieving the optimal image quality index 4.4 were 9.8, 32.2, 100.9, 241.4, and 274.1 mGy, respectively. For patients with lateral sizes of 43–58 cm, 120-kVp scan protocols yielded up to 165% greater radiation dose relative to 140-kVp protocols, and 140-kVp protocols always yielded a greater image quality index compared to the same dose-level 120-kVp protocols. The trace of target and organ dosimetry coverage and the ? passing rates of seven IMRT dose distribution pairs indicated the feasibility of the proposed image quality index for the predication strategy. Conclusions: A general strategy to predict the optimal CT simulation protocols in a flexible and quantitative way was developed that takes into account patient size, treatment planning task, and radiation dose. The experimental study indicated that the optimal CT simulation protocol and the corresponding radiation dose varied significantly for different patient sizes, contouring accuracy, and radiation treatment planning tasks.

  20. Simultaneous Detection and Registration for Ileo-Cecal Valve Detection in 3D CT Colonography

    E-Print Network [OSTI]

    Barbu, Adrian

    Simultaneous Detection and Registration for Ileo-Cecal Valve Detection in 3D CT Colonography Le Lu1-Cecal Valve (ICV) detection in both clean and tagged 3D CT colonography scans. Our final ICV detection system

  1. Test of 3D CT reconstructions by EM + TV algorithm from undersampled data

    SciTech Connect (OSTI)

    Evseev, Ivan; Ahmann, Francielle; Silva, Hamilton P. da

    2013-05-06

    Computerized tomography (CT) plays an important role in medical imaging for diagnosis and therapy. However, CT imaging is connected with ionization radiation exposure of patients. Therefore, the dose reduction is an essential issue in CT. In 2011, the Expectation Maximization and Total Variation Based Model for CT Reconstruction (EM+TV) was proposed. This method can reconstruct a better image using less CT projections in comparison with the usual filtered back projection (FBP) technique. Thus, it could significantly reduce the overall dose of radiation in CT. This work reports the results of an independent numerical simulation for cone beam CT geometry with alternative virtual phantoms. As in the original report, the 3D CT images of 128 Multiplication-Sign 128 Multiplication-Sign 128 virtual phantoms were reconstructed. It was not possible to implement phantoms with lager dimensions because of the slowness of code execution even by the CORE i7 CPU.

  2. Prostate CT segmentation method based on nonrigid registration in ultrasound-guided CT-based HDR prostate brachytherapy

    SciTech Connect (OSTI)

    Yang, Xiaofeng Rossi, Peter; Ogunleye, Tomi; Marcus, David M.; Jani, Ashesh B.; Curran, Walter J.; Liu, Tian; Mao, Hui

    2014-11-01

    Purpose: The technological advances in real-time ultrasound image guidance for high-dose-rate (HDR) prostate brachytherapy have placed this treatment modality at the forefront of innovation in cancer radiotherapy. Prostate HDR treatment often involves placing the HDR catheters (needles) into the prostate gland under the transrectal ultrasound (TRUS) guidance, then generating a radiation treatment plan based on CT prostate images, and subsequently delivering high dose of radiation through these catheters. The main challenge for this HDR procedure is to accurately segment the prostate volume in the CT images for the radiation treatment planning. In this study, the authors propose a novel approach that integrates the prostate volume from 3D TRUS images into the treatment planning CT images to provide an accurate prostate delineation for prostate HDR treatment. Methods: The authors’ approach requires acquisition of 3D TRUS prostate images in the operating room right after the HDR catheters are inserted, which takes 1–3 min. These TRUS images are used to create prostate contours. The HDR catheters are reconstructed from the intraoperative TRUS and postoperative CT images, and subsequently used as landmarks for the TRUS–CT image fusion. After TRUS–CT fusion, the TRUS-based prostate volume is deformed to the CT images for treatment planning. This method was first validated with a prostate-phantom study. In addition, a pilot study of ten patients undergoing HDR prostate brachytherapy was conducted to test its clinical feasibility. The accuracy of their approach was assessed through the locations of three implanted fiducial (gold) markers, as well as T2-weighted MR prostate images of patients. Results: For the phantom study, the target registration error (TRE) of gold-markers was 0.41 ± 0.11 mm. For the ten patients, the TRE of gold markers was 1.18 ± 0.26 mm; the prostate volume difference between the authors’ approach and the MRI-based volume was 7.28% ± 0.86%, and the prostate volume Dice overlap coefficient was 91.89% ± 1.19%. Conclusions: The authors have developed a novel approach to improve prostate contour utilizing intraoperative TRUS-based prostate volume in the CT-based prostate HDR treatment planning, demonstrated its clinical feasibility, and validated its accuracy with MRIs. The proposed segmentation method would improve prostate delineations, enable accurate dose planning and treatment delivery, and potentially enhance the treatment outcome of prostate HDR brachytherapy.

  3. Slowing the Increase in the Population Dose Resulting from CT Scans D. J. Brenner

    E-Print Network [OSTI]

    Brenner, David Jonathan

    is by far in the patient's favor. Nevertheless, CT should operate under the ALARA (As Low As Reasonably

  4. Molecular Simulation of Water Extraction into a Tri-n-Butyl-Phosphate/n-Dodecane Solution

    SciTech Connect (OSTI)

    de Almeida, Valmor F [ORNL] [ORNL; Ye, Xianggui [ORNL] [ORNL; Cui, Shengting [ORNL] [ORNL; Khomami, Bamin [ORNL] [ORNL

    2013-01-01

    Abstract: Molecular dynamics simulations were performed to investigate water extraction into a solution of 30 vol% tri-n-butyl-phosphate (TBP) in n-dodecane. This solvent extraction mixture is commonly used in hydrometallurgical and nuclear fuel recycling operations for recovering metals from aqueous streams. It is known that water is coextracted in the organic phase and that it competes with metal ions for the available extractant agent (TBP). Therefore investigating pure water extraction provides a realistic prototype to test molecular simulation methods for the first time in this area. Our computational results indicate that the TBP electric dipole moment has a significant effect on the predicted water solubility. A larger TBP dipole moment decreases the aqueous-organic interfacial tension, leading to increased roughness of the aqueous-organic interface. Interfacial roughness has a significant effect on disrupting the interfacial water hydrogen bonding structure, resulting in a greater number of dangling water molecules at the interface. This enhances the probability of water molecules to break away from the aqueous phase and to migrate into the bulk of the organic phase. Therefore, the magnitude of the TBP dipole moment is a crucial factor in controlling water hydrogen bond breaking at the aqueous-organic interface. By slightly lowering the atomic partial charges of the TBP atoms, to produce a dipole moment that better agrees with experimental data, we were able to predict water solubility in close agreement with experimental measurements. Hence we demonstrate that a molecular modeling and simulation approach may provide quantitative support to experimental programs in this area. In addition, our simulation results shed light into the molecular mechanism of water extraction, the critical role of TBP, and the structural forms of water molecules both at the interface and in the bulk of the organic phase. Specifically, it is found that water molecules are extracted either as single molecules or as clusters. Furthermore, within the organic phase, the extracted water forms clusters with up to 20 water molecules, however, more than 70% of these water clusters contain less than 5 water molecules when the water extraction process reaches saturation.

  5. The San Francisco Consortium CT Host, CE Home

    E-Print Network [OSTI]

    Ovchinnikov, Sergei

    The San Francisco Consortium CT Host, CE Home me l r Student: Complete Sections 1 through 5. Print Campus Campus California College of Podiatric Medicine City College of San Francisco Cogswell College Golden Gate University Tuition Required Hastings College of the Law San Francisco State University

  6. CT Poison Control Center 2014 Video Contest Rules

    E-Print Network [OSTI]

    Kim, Duck O.

    CT Poison Control Center 2014 Video Contest Rules To Enter: 1) Record and upload a video to your an immediate family member who is an employee of the Connecticut Poison Control Center. Video Requirements: · DO NOT HANDLE, INGEST OR USE ANY ACTUAL POISONOUS OR HAZARDOUSSUBSTANCES. IF YOU HAVE QUESTIONS ABOUT

  7. Collapsibility of Lung Volume by Paired Inspiratory and Expiratory CT

    E-Print Network [OSTI]

    Collapsibility of Lung Volume by Paired Inspiratory and Expiratory CT Scans: Correlations with Lung Function and Mean Lung Density Tsuneo Yamashiro, MD, Shin Matsuoka, MD, PhD, Brian J. Bartholmai, MD, Rau: To evaluate the relationship between measurements of lung volume (LV) on inspiratory/expiratory computed

  8. Targeted CT Screening for Lung Cancer using Absolute Risk Prediction

    E-Print Network [OSTI]

    Brent, Roger

    Targeted CT Screening for Lung Cancer using Absolute Risk Prediction Stephanie A. Kovalchik skovalch@rand.org FHCRC 2014 Risk Prediction Symposium June 11, 2014 1 #12;Outline · Lung Cancer Epidemiology and Screening · Screening Benefit and Absolute Risk · Absolute Risk Model for Lung Cancer

  9. Soft Classification with Gaussian Mixture Model for Clinical Dual-Energy CT Reconstructions

    E-Print Network [OSTI]

    1 Soft Classification with Gaussian Mixture Model for Clinical Dual-Energy CT Reconstructions, and Ken D. Sauer, Member, IEEE Abstract--We study the distribution of the clinical dual-energy CT (DECT material separation. Index Terms--Computed tomography (CT), dual energy, sta- tistical method, Gaussian

  10. Fractional scan algorithms for low-dose perfusion CT Jiang Hsieha)

    E-Print Network [OSTI]

    Wang, Ge

    Fractional scan algorithms for low-dose perfusion CT Jiang Hsieha) GE Medical Systems, Milwaukee be reconstructed at a fraction of the nominal radiation dose. © 2004 American Asso- ciation of Physicists to perform perfusion CT at a significantly reduced x-ray dose. One method to achieve low-dose CT is to reduce

  11. Automatic Lung Nodule Detection from Chest CT Data Using Geometrical Features: Initial Results

    E-Print Network [OSTI]

    Whelan, Paul F.

    Automatic Lung Nodule Detection from Chest CT Data Using Geometrical Features: Initial Results for automatic lung nodule detection from Chest CT data is proposed. The proposed system includes the methods of lung segmentation and nodule detection from CT data. The algorithm for lung segmentation consists

  12. Robust Segmentation of Challenging Lungs in CT using Multi-Stage Learning

    E-Print Network [OSTI]

    Robust Segmentation of Challenging Lungs in CT using Multi-Stage Learning and Level Set.Kevin Zhou1 Abstract Automatic segmentation of lung tissue in thoracic CT scans is useful for diagnosis and treatment planning of pulmonary diseases. Unlike healthy lung tissue that is easily identifiable in CT scans

  13. Augmenting CT Cardiac Roadmaps with Segmented Streaming Qi Duan a,b

    E-Print Network [OSTI]

    Augmenting CT Cardiac Roadmaps with Segmented Streaming Ultrasound Qi Duan a,b , Guy Shechter Static X-ray computed tomography (CT) volumes are often used as anatomic roadmaps during catheter. Augmenting these static CT roadmaps with segmented myocardial borders extracted from live ultrasound (US

  14. Tri-State Synfuels Project Review: Volume 12. Fluor project status. [Proposed Henderson, Kentucky coal to gasoline plant; engineering

    SciTech Connect (OSTI)

    Not Available

    1982-06-01

    The purpose of this report is to document and summarize activities associated with Fluor's efforts on the Tri-State Synfuels Project. The proposed facility was to be coal-to-transport fuels facility located in Henderson, Kentucky. Tri-State Synfuels Company was participating in the project as a partner of the US Department of Energy per terms of a Cooperative Agreement resulting from DOE's synfuel's program solicitation. Fluor's initial work plan called for preliminary engineering and procurement services to the point of commitment for construction for a Sasol Fischer-Tropsch plant. Work proceeded as planned until October 1981 when results of alternative coal-to-methanol studies revealed the economic disadvantage of the Synthol design for US markets. A number of alternative process studies followed to determine the best process configuration. In January 1982 Tri-State officially announced a change from Synthol to a Methanol to Gasoline (MTG) design basis. Further evaluation and cost estimates for the MTG facility eventually led to the conclusion that, given the depressed economic outlook for alternative fuels development, the project should be terminated. Official announcement of cancellation was made on April 13, 1982. At the time of project cancellation, Fluor had completed significant portions of the preliminary engineering effort. Included in this report are descriptions and summaries of Fluor's work during this project. In addition location of key project data and materials is identified and status reports for each operation are presented.

  15. Quantitative cone-beam CT imaging in radiation therapy using planning CT as a prior: First patient studies

    SciTech Connect (OSTI)

    Niu Tianye; Al-Basheer, Ahmad; Zhu Lei [Nuclear and Radiological Engineering and Medical Physics Programs, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Georgia Radiation Therapy Center, Department of Radiology, Georgia Health Sciences University, Augusta, Georgia 30912 (United States); Nuclear and Radiological Engineering and Medical Physics Programs, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)

    2012-04-15

    Purpose: Quantitative cone-beam CT (CBCT) imaging is on increasing demand for high-performance image guided radiation therapy (IGRT). However, the current CBCT has poor image qualities mainly due to scatter contamination. Its current clinical application is therefore limited to patient setup based on only bony structures. To improve CBCT imaging for quantitative use, we recently proposed a correction method using planning CT (pCT) as the prior knowledge. Promising phantom results have been obtained on a tabletop CBCT system, using a correction scheme with rigid registration and without iterations. More challenges arise in clinical implementations of our method, especially because patients have large organ deformation in different scans. In this paper, we propose an improved framework to extend our method from bench to bedside by including several new components. Methods: The basic principle of our correction algorithm is to estimate the primary signals of CBCT projections via forward projection on the pCT image, and then to obtain the low-frequency errors in CBCT raw projections by subtracting the estimated primary signals and low-pass filtering. We improve the algorithm by using deformable registration to minimize the geometry difference between the pCT and the CBCT images. Since the registration performance relies on the accuracy of the CBCT image, we design an optional iterative scheme to update the CBCT image used in the registration. Large correction errors result from the mismatched objects in the pCT and the CBCT scans. Another optional step of gas pocket and couch matching is added into the framework to reduce these effects. Results: The proposed method is evaluated on four prostate patients, of which two cases are presented in detail to investigate the method performance for a large variety of patient geometry in clinical practice. The first patient has small anatomical changes from the planning to the treatment room. Our algorithm works well even without the optional iterations and the gas pocket and couch matching. The image correction on the second patient is more challenging due to the effects of gas pockets and attenuating couch. The improved framework with all new components is used to fully evaluate the correction performance. The enhanced image quality has been evaluated using mean CT number and spatial nonuniformity (SNU) error as well as contrast improvement factor. If the pCT image is considered as the ground truth, on the four patients, the overall mean CT number error is reduced from over 300 HU to below 16 HU in the selected regions of interest (ROIs), and the SNU error is suppressed from over 18% to below 2%. The average soft-tissue contrast is improved by an average factor of 2.6. Conclusions: We further improve our pCT-based CBCT correction algorithm for clinical use. Superior correction performance has been demonstrated on four patient studies. By providing quantitative CBCT images, our approach significantly increases the accuracy of advanced CBCT-based clinical applications for IGRT.

  16. Sci—Thur PM: Imaging — 06: Canada's National Computed Tomography (CT) Survey

    SciTech Connect (OSTI)

    Wardlaw, GM; Martel, N; Blackler, W; Asselin, J-F

    2014-08-15

    The value of computed tomography (CT) in medical imaging is reflected in its' increased use and availability since the early 1990's; however, given CT's relatively larger exposures (vs. planar x-ray) greater care must be taken to ensure that CT procedures are optimised in terms of providing the smallest dose possible while maintaining sufficient diagnostic image quality. The development of CT Diagnostic Reference Levels (DRLs) supports this process. DRLs have been suggested/supported by international/national bodies since the early 1990's and widely adopted elsewhere, but not on a national basis in Canada. Essentially, CT DRLs provide guidance on what is considered good practice for common CT exams, but require a representative sample of CT examination data to make any recommendations. Canada's National CT Survey project, in collaboration with provincial/territorial authorities, has collected a large national sample of CT practice data for 7 common examinations (with associated clinical indications) of both adult and pediatric patients. Following completion of data entry into a common database, a survey summary report and recommendations will be made on CT DRLs from this data. It is hoped that these can then be used by local regions to promote CT practice optimisation and support any dose reduction initiatives.

  17. AMP-activated protein kinase phosphorylates CtBP1 and down-regulates its activity

    SciTech Connect (OSTI)

    Kim, Jae-Hwan; Choi, Soo-Youn; Kang, Byung-Hee; Lee, Soon-Min [National Creative Research Center for Epigenome Reprogramming Network, Departments of Biomedical Sciences and Biochemistry and Molecular Biology, Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul 110-799 (Korea, Republic of)] [National Creative Research Center for Epigenome Reprogramming Network, Departments of Biomedical Sciences and Biochemistry and Molecular Biology, Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul 110-799 (Korea, Republic of); Park, Hyung Soon; Kang, Gum-Yong; Bang, Joo Young [Center for Biomedical Mass Spectrometry, Diatech Korea Co., Ltd., Seoul (Korea, Republic of)] [Center for Biomedical Mass Spectrometry, Diatech Korea Co., Ltd., Seoul (Korea, Republic of); Cho, Eun-Jung [National Research Laboratory for Chromatin Dynamics, College of Pharmacy, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)] [National Research Laboratory for Chromatin Dynamics, College of Pharmacy, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Youn, Hong-Duk, E-mail: hdyoun@snu.ac.kr [National Creative Research Center for Epigenome Reprogramming Network, Departments of Biomedical Sciences and Biochemistry and Molecular Biology, Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul 110-799 (Korea, Republic of) [National Creative Research Center for Epigenome Reprogramming Network, Departments of Biomedical Sciences and Biochemistry and Molecular Biology, Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul 110-799 (Korea, Republic of); WCU Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence and Technology, Seoul National University, Seoul (Korea, Republic of)

    2013-02-01

    Highlights: ? AMPK phosphorylates CtBP1 on serine 158. ? AMPK-mediated phosphorylation of CtBP1 causes the ubiquitination and nuclear export of CtBP1. ? AMPK downregulates the CtBP1-mediated repression of Bax transcription. -- Abstract: CtBP is a transcriptional repressor which plays a significant role in the regulation of cell proliferation and tumor progression. It was reported that glucose withdrawal causes induction of Bax due to the dissociation of CtBP from the Bax promoter. However, the precise mechanism involved in the regulation of CtBP still remains unclear. In this study, we found that an activated AMP-activated protein kinase (AMPK) phosphorylates CtBP1 on Ser-158 upon metabolic stresses. Moreover, AMPK-mediated phosphorylation of CtBP1 (S158) attenuates the repressive function of CtBP1. We also confirmed that triggering activation of AMPK by various factors resulted in an increase of Bax gene expression. These findings provide connections of AMPK with CtBP1-mediated regulation of Bax expression for cell death under metabolic stresses.

  18. Exploring and exchanging (dis)ability and (dis)aster 

    E-Print Network [OSTI]

    Stough, Laura; Kelman, Ilan

    2015-01-01

    and deal with, leaving them less energy for dealing with less frequent hazards. Some chapters point out that disasters can also lead to disability, from Ferreira losing her leg in a nightclub fire to Mr. HP and Mrs. KB experiencing the Gujarat...

  19. Utilizing a simple CT dosimetry phantom for the comprehension of the operational characteristics of CT AEC systems

    SciTech Connect (OSTI)

    Tsalafoutas, Ioannis A.; Varsamidis, Athanasios; Thalassinou, Stella; Efstathopoulos, Efstathios P.

    2013-11-15

    Purpose: To investigate the utility of the nested polymethylacrylate (PMMA) phantom (which is available in many CT facilities for CTDI measurements), as a tool for the presentation and comparison of the ways that two different CT automatic exposure control (AEC) systems respond to a phantom when various scan parameters and AEC protocols are modified.Methods: By offsetting the two phantom's components (the head phantom and the body ring) half-way along their longitudinal axis, a phantom with three sections of different x-ray attenuation was created. Scan projection radiographs (SPRs) and helical scans of the three-section phantom were performed on a Toshiba Aquilion 64 and a Philips Brilliance 64 CT scanners, with different scan parameter selections [scan direction, pitch factor, slice thickness, and reconstruction interval (ST/RI), AEC protocol, and tube potential used for the SPRs]. The dose length product (DLP) values of each scan were recorded and the tube current (mA) values of the reconstructed CT images were plotted against the respective Z-axis positions on the phantom. Furthermore, measurements of the noise levels at the center of each phantom section were performed to assess the impact of mA modulation on image quality.Results: The mA modulation patterns of the two CT scanners were very dissimilar. The mA variations were more pronounced for Aquilion 64, where changes in any of the aforementioned scan parameters affected both the mA modulations curves and DLP values. However, the noise levels were affected only by changes in pitch, ST/RI, and AEC protocol selections. For Brilliance 64, changes in pitch affected the mA modulation curves but not the DLP values, whereas only AEC protocol and SPR tube potential selection variations affected both the mA modulation curves and DLP values. The noise levels increased for smaller ST/RI, larger weight category AEC protocol, and larger SPR tube potential selection.Conclusions: The nested PMMA dosimetry phantom can be effectively utilized for the comprehension of CT AEC systems performance and the way that different scan conditions affect the mA modulation patterns, DLP values, and image noise. However, in depth analysis of the reasons why these two systems exhibited such different behaviors in response to the same phantom requires further investigation which is beyond the scope of this study.

  20. Upright cone beam CT imaging using the onboard imager

    SciTech Connect (OSTI)

    Fave, Xenia Martin, Rachael; Yang, Jinzhong; Balter, Peter; Court, Laurence; Carvalho, Luis; Pan, Tinsu

    2014-06-15

    Purpose: Many patients could benefit from being treated in an upright position. The objectives of this study were to determine whether cone beam computed tomography (CBCT) could be used to acquire upright images for treatment planning and to demonstrate whether reconstruction of upright images maintained accurate geometry and Hounsfield units (HUs). Methods: A TrueBeam linac was programmed in developer mode to take upright CBCT images. The gantry head was positioned at 0°, and the couch was rotated to 270°. The x-ray source and detector arms were extended to their lateral positions. The x-ray source and gantry remained stationary as fluoroscopic projections were taken and the couch was rotated from 270° to 90°. The x-ray tube current was normalized to deposit the same dose (measured using a calibrated Farmer ion chamber) as that received during a clinical helical CT scan to the center of a cylindrical, polyethylene phantom. To extend the field of view, two couch rotation scans were taken with the detector offset 15 cm superiorly and then 15 cm inferiorly. The images from these two scans were stitched together before reconstruction. Upright reconstructions were compared to reconstructions from simulation CT scans of the same phantoms. Two methods were investigated for correcting the HUs, including direct calibration and mapping the values from a simulation CT. Results: Overall geometry, spatial linearity, and high contrast resolution were maintained in upright reconstructions. Some artifacts were created and HU accuracy was compromised; however, these limitations could be removed by mapping the HUs from a simulation CT to the upright reconstruction for treatment planning. Conclusions: The feasibility of using the TrueBeam linac to take upright CBCT images was demonstrated. This technique is straightforward to implement and could be of enormous benefit to patients with thoracic tumors or those who find a supine position difficult to endure.

  1. The CT14 Global Analysis of Quantum Chromodynamics

    E-Print Network [OSTI]

    Dulat, Sayipjamal; Gao, Jun; Guzzi, Marco; Huston, Joey; Nadolsky, Pavel; Pumplin, Jon; Schmidt, Carl; Stump, Daniel; Yuan, C P

    2015-01-01

    We present new parton distribution functions (PDFs) up to next-to-next-to-leading order (NNLO) from the CTEQ-TEA global analysis of quantum chromodynamics. These differ from previous CT PDFs in several respects, including the use of data from LHC experiments and the new D0 charged lepton rapidity asymmetry data, as well as the use of more flexible parametrization of PDFs that, in particular, allows a better fit to different combinations of quark flavors. Predictions for important LHC processes, especially Higgs boson production at 13 TeV, are presented. These CT14 PDFs include a central set and error sets in the Hessian representation. For completeness, we also present the CT14 PDFs determined at the leading order (LO) and the next-to-leading order (NLO) in QCD. Besides these general-purpose PDF sets, we provide a series of (N)NLO sets with various $\\alpha_s$ values and additional sets in heavy-quark scheme with up to 3, 4, and 6 active flavors.

  2. The CT14 Global Analysis of Quantum Chromodynamics

    E-Print Network [OSTI]

    Sayipjamal Dulat; Tie Jiun Hou; Jun Gao; Marco Guzzi; Joey Huston; Pavel Nadolsky; Jon Pumplin; Carl Schmidt; Daniel Stump; C. P. Yuan

    2015-08-02

    We present new parton distribution functions (PDFs) up to next-to-next-to-leading order (NNLO) from the CTEQ-TEA global analysis of quantum chromodynamics. These differ from previous CT PDFs in several respects, including the use of data from LHC experiments and the new D0 charged lepton rapidity asymmetry data, as well as the use of more flexible parametrization of PDFs that, in particular, allows a better fit to different combinations of quark flavors. Predictions for important LHC processes, especially Higgs boson production at 13 TeV, are presented. These CT14 PDFs include a central set and error sets in the Hessian representation. For completeness, we also present the CT14 PDFs determined at the leading order (LO) and the next-to-leading order (NLO) in QCD. Besides these general-purpose PDF sets, we provide a series of (N)NLO sets with various $\\alpha_s$ values and additional sets in general-mass variable flavor number (GM-VFN) schemes, to deal with heavy partons, with up to 3, 4, and 6 active flavors.

  3. White Paper on Ion Beam Transport for ICF: Issues, R&D Need,and Tri-Lab Plans

    SciTech Connect (OSTI)

    Olson, C.; Lee, E.; Langdon, B.

    2005-05-04

    To date, most resources for ion beam fusion have been devoted to development of accelerators and target physics; relatively few resources have gone into ion beam transport development. Because of theoretical studies and substantial experience with electron beam transport, the ion beam transport community is now poised to develop and optimize ion beam transport for ICF. Because of this Tri-Lab effort, a path for coordinated development of ion beam transport has been established. The rate of progress along this path will now be determined largely by the availability of resources.

  4. Method for photochemical reduction of uranyl nitrate by tri-N-butyl phosphate and application of this method to nuclear fuel reprocessing

    DOE Patents [OSTI]

    De Poorter, Gerald L. (Los Alamos, NM); Rofer-De Poorter, Cheryl K. (Los Alamos, NM)

    1978-01-01

    Uranyl ion in solution in tri-n-butyl phosphate is readily photochemically reduced to U(IV). The product U(IV) may effectively be used in the Purex process for treating spent nuclear fuels to reduce Pu(IV) to Pu(III). The Pu(III) is readily separated from uranium in solution in the tri-n-butyl phosphate by an aqueous strip.

  5. Ultralow dose computed tomography attenuation correction for pediatric PET CT using adaptive statistical iterative reconstruction

    SciTech Connect (OSTI)

    Brady, Samuel L.; Shulkin, Barry L.

    2015-02-15

    Purpose: To develop ultralow dose computed tomography (CT) attenuation correction (CTAC) acquisition protocols for pediatric positron emission tomography CT (PET CT). Methods: A GE Discovery 690 PET CT hybrid scanner was used to investigate the change to quantitative PET and CT measurements when operated at ultralow doses (10–35 mA s). CT quantitation: noise, low-contrast resolution, and CT numbers for 11 tissue substitutes were analyzed in-phantom. CT quantitation was analyzed to a reduction of 90% volume computed tomography dose index (0.39/3.64; mGy) from baseline. To minimize noise infiltration, 100% adaptive statistical iterative reconstruction (ASiR) was used for CT reconstruction. PET images were reconstructed with the lower-dose CTAC iterations and analyzed for: maximum body weight standardized uptake value (SUV{sub bw}) of various diameter targets (range 8–37 mm), background uniformity, and spatial resolution. Radiation dose and CTAC noise magnitude were compared for 140 patient examinations (76 post-ASiR implementation) to determine relative dose reduction and noise control. Results: CT numbers were constant to within 10% from the nondose reduced CTAC image for 90% dose reduction. No change in SUV{sub bw}, background percent uniformity, or spatial resolution for PET images reconstructed with CTAC protocols was found down to 90% dose reduction. Patient population effective dose analysis demonstrated relative CTAC dose reductions between 62% and 86% (3.2/8.3–0.9/6.2). Noise magnitude in dose-reduced patient images increased but was not statistically different from predose-reduced patient images. Conclusions: Using ASiR allowed for aggressive reduction in CT dose with no change in PET reconstructed images while maintaining sufficient image quality for colocalization of hybrid CT anatomy and PET radioisotope uptake.

  6. Semi-automatic delineation using weighted CT-MRI registered images...

    Office of Scientific and Technical Information (OSTI)

    delineation using weighted CT-MRI registered images for radiotherapy of nasopharyngeal cancer Citation Details In-Document Search Title: Semi-automatic delineation using weighted...

  7. An algorithm for constrained one-step inversion of spectral CT data

    E-Print Network [OSTI]

    Barber, Rina Foygel; Schmidt, Taly Gilat; Pan, Xiaochuan

    2015-01-01

    We develop a primal-dual algorithm that allows for one-step inversion of spectral CT transmission photon counts data to a basis map decomposition. The algorithm allows for image constraints to be enforced on the basis maps during the inversion. The derivation of the algorithm makes use of a local upper bounding quadratic approximation to generate descent steps for non-convex spectral CT data discrepancy terms, combined with a new convex-concave optimization algorithm. Convergence of the algorithm is demonstrated on simulated spectral CT data. Simulations with noise and anthropomorphic phantoms show examples of how to employ the constrained one-step algorithm for spectral CT data.

  8. Embedded Library in WebCT: Pushing UCSD Library Resources to Faculty Courses

    E-Print Network [OSTI]

    Ho, SuHui

    2007-01-01

    keeper about pushing the library to department pages & webEmbedded Library in WebCT:Pushing UCSD Library Resources to Faculty Courses Presenter:

  9. A Fossilized Opal A To Opal C-T Transformation On The Northeast...

    Open Energy Info (EERE)

    A Fossilized Opal A To Opal C-T Transformation On The Northeast Atlantic Margin- Support For A Significantly Elevated Palaeogeothermal Gradient During The Neogene? Jump to:...

  10. Automated matching and segmentation of lymphoma on serial CT examinations

    SciTech Connect (OSTI)

    Yan Jiayong; Zhao Binsheng; Curran, Sean; Zelenetz, Andrew; Schwartz, Lawrence H.

    2007-01-15

    In patients with lymphoma, identification and quantification of the tumor extent on serial CT examinations is critical for assessing tumor response to therapy. In this paper, we present a computer method to automatically match and segment lymphomas in follow-up CT images. The method requires that target lymph nodes in baseline CT images be known. A fast, approximate alignment technique along the x, y, and axial directions is developed to provide a good initial condition for the subsequent fast free form deformation (FFD) registration of the baseline and the follow-up images. As a result of the registration, the deformed lymph node contours from the baseline images are used to automatically determine internal and external markers for the marker-controlled watershed segmentation performed in the follow-up images. We applied this automated registration and segmentation method retrospectively to 29 lymph nodes in 9 lymphoma patients treated in a clinical trial at our cancer center. A radiologist independently delineated all lymph nodes on all slices in the follow-up images and his manual contours served as the ''gold standard'' for evaluation of the method. Preliminary results showed that 26/29 (89.7%) lymph nodes were correctly matched; i.e., there was a geometrical overlap between the deformed lymph node from the baseline and its corresponding mass in the follow-up images. Of the matched 26 lymph nodes, 22 (84.6%) were successfully segmented; for these 22 lymph nodes, several metrics were calculated to quantify the method's performance. Among them, the average distance and the Hausdorff distance between the contours generated by the computer and those generated by the radiologist were 0.9 mm (stdev. 0.4 mm) and 3.9 mm (stdev. 2.1 mm), respectively.

  11. CT Scans of Cores Metadata, Barrow, Alaska 2015

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Katie McKnight; Tim Kneafsey; Craig Ulrich

    2015-03-11

    Individual ice cores were collected from Barrow Environmental Observatory in Barrow, Alaska, throughout 2013 and 2014. Cores were drilled along different transects to sample polygonal features (i.e. the trough, center and rim of high, transitional and low center polygons). Most cores were drilled around 1 meter in depth and a few deep cores were drilled around 3 meters in depth. Three-dimensional images of the frozen cores were constructed using a medical X-ray computed tomography (CT) scanner. TIFF files can be uploaded to ImageJ (an open-source imaging software) to examine soil structure and densities within each core.

  12. Pre-processing methods for nodule detection in lung CT

    E-Print Network [OSTI]

    Cheran, S C; De Mitri, I; De Nunzio, G; Fantacci, M E; Fauci, F; Gargano, G; Torres, E L; Massafra, R; Oliva, P; Pérez-Martínez, A; Raso, G; Retico, A; Stumbo, S; Tata, A

    2005-01-01

    The use of automatic systems in the analysis of medical images has proven to be very useful to radiologists, especially in the framework of screening programs, in which radiologists make their first diagnosis on the basis of images only, most of those corresponding to healthy patients, and have to distinguish pathological findings from non-pathological ones at an early stage. In particular, we are developing preprocessing methods to be applied for pulmonary nodule Computer Aided Detection in low-dose lung Multi Slice CT (Computed Tomography) images.

  13. CT Scans of Cores Metadata, Barrow, Alaska 2015

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Katie McKnight; Tim Kneafsey; Craig Ulrich

    Individual ice cores were collected from Barrow Environmental Observatory in Barrow, Alaska, throughout 2013 and 2014. Cores were drilled along different transects to sample polygonal features (i.e. the trough, center and rim of high, transitional and low center polygons). Most cores were drilled around 1 meter in depth and a few deep cores were drilled around 3 meters in depth. Three-dimensional images of the frozen cores were constructed using a medical X-ray computed tomography (CT) scanner. TIFF files can be uploaded to ImageJ (an open-source imaging software) to examine soil structure and densities within each core.

  14. DOE - Office of Legacy Management -- American Brass Co - CT 01

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth Dakota Edgemont, South Dakota,You are hereNY 01NJBrass Co - CT 01

  15. CT Scan of Earth Links Mantle Plumes with Volcanic Hotspots

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAudits &BradburyMay 1, 2013, 4:15pmEnergyNovemberComputeCSTEC EnergyCT

  16. BAIC CT T SK Holdings JV | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EAandAmminex AAustria Geothermal RegionAvraPáginasSolar JumpPowerBAIC CT T

  17. Controlled Synthesis of Uniform Cobalt Phosphide Hyperbranched Nanocrystals Using Tri-n-octylphosphine Oxide as a Phosphorus Source

    SciTech Connect (OSTI)

    Zhang, Haitao; Ha, Don-Hyung; Hovden, Robert; Fitting Kourkoutis, Lena; Robinson, Richard D.

    2011-01-12

    A new method to produce hyperbranched Co{sub 2}P nanocrystals that are uniform in size, shape, and symmetry was developed. In this reaction tri-n-octylphosphine oxide (TOPO) was used as both a solvent and a phosphorus source. The reaction exhibits a novel monomer-saturation-dependent tunability between Co metal nanoparticle (NP) and Co{sub 2}P NP products. The morphology of Co{sub 2}P can be controlled from sheaflike structures to hexagonal symmetric structures by varying the concentration of the surfactant. This unique product differs significantly from other reported hyperbranched nanocrystals in that the highly anisotropic shapes can be stabilized as the majority shape (>84%). This is the first known use of TOPO as a reagent as well as a coordinating background solvent in NP synthesis.

  18. A Model-Based Iterative Algorithm for Dual-Energy X-Ray CT Reconstruction

    E-Print Network [OSTI]

    A Model-Based Iterative Algorithm for Dual-Energy X-Ray CT Reconstruction Ruoqiao Zhang, Jean, Senior Member, IEEE Abstract--Recent developments in dual-energy X-ray CT have shown a number of benefits the opportunity to reduce noise and artifacts in dual energy reconstructions. However, previous approaches

  19. Surface Extraction from Multi-Material Components for Metrology using Dual Energy CT

    E-Print Network [OSTI]

    Surface Extraction from Multi-Material Components for Metrology using Dual Energy CT Christoph surface models of multi-material components using dual energy com- puted tomography (DECT exposure scans was facilitated. Index Terms--DECT image fusion, local surface extraction, Dual Energy CT

  20. Automated segmentation of lungs with severe interstitial lung disease in CT

    E-Print Network [OSTI]

    Automated segmentation of lungs with severe interstitial lung disease in CT Jiahui Wang Department: Accurate segmentation of lungs with severe interstitial lung disease ILD in thoracic computed tomography CT developed in this study a texture analysis-based method for accurate segmentation of lungs with severe ILD

  1. Location registration and recognition (LRR) for serial analysis of nodules in lung CT scans

    E-Print Network [OSTI]

    Location registration and recognition (LRR) for serial analysis of nodules in lung CT scans Michal t In the clinical workflow for lung cancer management, the comparison of nodules between CT scans from subsequent in investigating the condition of the lung. The algorithm uses a combination of feature extraction, indexing

  2. AUTOMATIC HEART ISOLATION FOR CT CORONARY VISUALIZATION USING G. Funka-Lea1

    E-Print Network [OSTI]

    Boykov, Yuri

    AUTOMATIC HEART ISOLATION FOR CT CORONARY VISUALIZATION USING GRAPH-CUTS G. Funka-Lea1 , Y. Boykov3 isolate the outer surface of the entire heart in Computer Tomogra- phy (CT) cardiac scans. Isolating the entire heart allows the coronary vessels on the surface of the heart to be easily visu- alized despite

  3. Multi-level Ground Glass Nodule Detection and Segmentation in CT Lung Images

    E-Print Network [OSTI]

    Corso, Jason J.

    Multi-level Ground Glass Nodule Detection and Segmentation in CT Lung Images Yimo Tao1,2 , Le Lu1. Early detection of Ground Glass Nodule (GGN) in lung Computed Tomography (CT) images is important for lung cancer prog- nosis. Due to its indistinct boundaries, manual detection and segmenta- tion of GGN

  4. University of Connecticut School of Nursing, 231 Glenbrook Road, Storrs, CT 062692026 NEWS RELEASE

    E-Print Network [OSTI]

    Alpay, S. Pamir

    University of Connecticut School of Nursing, 231 Glenbrook Road, Storrs, CT 062692026 NEWS, 2015 Storrs, CT - The University of Connecticut School of Nursing jumped 36 spots from a No. 79 ranking, students, community partners and alumni at the University of Connecticut's School of Nursing," said Dean

  5. Lobe-based Estimating Ventilation and Perfusion from 3D CT scans of the Lungs

    E-Print Network [OSTI]

    Warren, Joe

    Lobe-based Estimating Ventilation and Perfusion from 3D CT scans of the Lungs Travis McPhail Joe Warren Rice University Thomas Guerrero, M.D. M.D. Anderson Cancer Center Introduction Lung cancer for lung cancer includes surgical removal or radiation therapy. 3D imaging technologies such CT, MRI

  6. ROBUST SEGMENTATION OF LUNG TISSUE IN CHEST CT SCANNING Amal Farag, James Graham and Aly Farag

    E-Print Network [OSTI]

    Louisville, University of

    ROBUST SEGMENTATION OF LUNG TISSUE IN CHEST CT SCANNING Amal Farag, James Graham and Aly Farag.edu ABSTRACT This paper deals with segmentation of the lung tissues from low dose CT (LDCT) scans of the chest. Goal is correct segmentation as well as maintaining the details of the lung region in the chest cavity

  7. Proceedings of MICCAI 2010 Workshop: Virtual Colonoscopy & Abdominal Imaging Recent advances in automated lesion detection for CT

    E-Print Network [OSTI]

    van Vliet, Lucas J.

    , techniques for CT colonography evolved rapidly, stimulated by encouraging performance data. Computer aided: computer aided detection, CT colonography, virtual colonoscopy. 1 Introduction Computed tomographic compliance. For digitally removing` the tagged materials, electronic cleansing (EC) methods were developed [1

  8. Abstract --Four-dimensional dynamic computed tomography (4D-dCT) plays an important role in radiation treatment

    E-Print Network [OSTI]

    dose during a 4D-dCT procedure is much higher than a routine 3D CT study. Low-dose scans for 4D with low-dose dynamic CT scans. It first applies the Karhunen-Loève (KL) transform to the neighboring-CT datasets are usually acquired in treatment planning for lung cancer [1]-[3]. Thus, the radiation dose of 4D

  9. Try This: Household Magnets

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout / TransformingTransuranicTrillion Advanced UsageHousehold

  10. Tri-Lab Resources

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With U.S.WeekProducts >TransportationEHSSTrending:

  11. Dual energy CT-based characterization of x-ray attenuation properties of breast equivalent material plates

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Dual energy CT-based characterization of x-ray attenuation properties of breast equivalent material of the same nominal breast density equivalence (+ 1.5 HU). In addition, dual energy CT provided mono equivalent material, breast density, attenuation properties, linear attenuation coefficients, dual energy CT

  12. Statistical analysis of Multi-Material Components using Dual Energy CT Christoph Heinzl, Johann Kastner, Torsten Moller, and Eduard Groller

    E-Print Network [OSTI]

    Statistical analysis of Multi-Material Components using Dual Energy CT Christoph Heinzl, Johann plastics-metal components. The presented work makes use of dual energy CT data acquisi- tion for artefact pipeline based on the dual ex- posure technique of dual energy CT. After prefilter- ing and multi

  13. Abstract-Proton Computed Tomography (CT) has important implications for both image-guided diagnosis and radiation

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Abstract- Proton Computed Tomography (CT) has important implications for both image-guided diagnosis and radiation therapy. For diagnosis, the fact that the patient dose committed by proton CT and contrast, may be exploited in dose-critical clinical settings. Proton CT is also the most appropriate

  14. for Proton CT R. P. Johnson, Member, IEEE, V. Bashkirov, V. Giacometti, R. F. Hurley, P. Piersimoni,

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    for Proton CT R. P. Johnson, Member, IEEE, V. Bashkirov, V. Giacometti, R. F. Hurley, P. Piersimoni beam test results with our pre-clinical (Phase-II) head scanner developed for proton computed tomography (pCT). After extensive preclinical testing, pCT will be employed in support of proton therapy

  15. Abstract ---Computed tomography colonography (CTC) or CT-based virtual colonoscopy (VC) is an emerging tool for detection

    E-Print Network [OSTI]

    . The radiation dose is a major concern for screening application of CTC. In this work, we performed a simulation study to demonstrate a possible ultra low-dose CT technique for VC. The ultra low-dose abdominal CT by a filtered backprojection algorithm for the ultra low-dose CT images. The patient-specific virtual colon

  16. Noise properties of low-dose X-ray CT sinogram data in Radon space , Hongbing Lu2

    E-Print Network [OSTI]

    Noise properties of low-dose X-ray CT sinogram data in Radon space Jing Wang1 , Hongbing Lu2 statistical moments will improve low-dose CT image reconstruction for screening applications. Keywords: Low-dose]. However, clinical use of CT frequently exposes the patients to excessive X-ray radiation [4

  17. T4DT: Processing 4D CT scans of the Lungs Robert Fowler Joe Warren Yin Zhang

    E-Print Network [OSTI]

    Warren, Joe

    T4DT: Processing 4D CT scans of the Lungs Robert Fowler Joe Warren Yin Zhang Rice University technology for processing time-varying CT scans (4D CT) of the lungs. In particular, we propose to develop these tools to quantitatively assess the effectiveness of current treatments for lung cancer. #12;T4DT

  18. A knowledge-based cone-beam x-ray CT algorithm for dynamic volumetric cardiac imaging

    E-Print Network [OSTI]

    Wang, Ge

    A knowledge-based cone-beam x-ray CT algorithm for dynamic volumetric cardiac imaging Ge Wanga, and wider coverage with multislice/cone- beam CT indicate a great potential for dynamic volumetric imaging/ helical multislice/cone-beam CT approach for dynamic volumetric cardiac imaging. This approach assumes

  19. Investigation of statistical iterative reconstruction for dedicated breast CT

    SciTech Connect (OSTI)

    Makeev, Andrey; Glick, Stephen J.

    2013-08-15

    Purpose: Dedicated breast CT has great potential for improving the detection and diagnosis of breast cancer. Statistical iterative reconstruction (SIR) in dedicated breast CT is a promising alternative to traditional filtered backprojection (FBP). One of the difficulties in using SIR is the presence of free parameters in the algorithm that control the appearance of the resulting image. These parameters require tuning in order to achieve high quality reconstructions. In this study, the authors investigated the penalized maximum likelihood (PML) method with two commonly used types of roughness penalty functions: hyperbolic potential and anisotropic total variation (TV) norm. Reconstructed images were compared with images obtained using standard FBP. Optimal parameters for PML with the hyperbolic prior are reported for the task of detecting microcalcifications embedded in breast tissue.Methods: Computer simulations were used to acquire projections in a half-cone beam geometry. The modeled setup describes a realistic breast CT benchtop system, with an x-ray spectra produced by a point source and an a-Si, CsI:Tl flat-panel detector. A voxelized anthropomorphic breast phantom with 280 ?m microcalcification spheres embedded in it was used to model attenuation properties of the uncompressed woman's breast in a pendant position. The reconstruction of 3D images was performed using the separable paraboloidal surrogates algorithm with ordered subsets. Task performance was assessed with the ideal observer detectability index to determine optimal PML parameters.Results: The authors' findings suggest that there is a preferred range of values of the roughness penalty weight and the edge preservation threshold in the penalized objective function with the hyperbolic potential, which resulted in low noise images with high contrast microcalcifications preserved. In terms of numerical observer detectability index, the PML method with optimal parameters yielded substantially improved performance (by a factor of greater than 10) compared to FBP. The hyperbolic prior was also observed to be superior to the TV norm. A few of the best-performing parameter pairs for the PML method also demonstrated superior performance for various radiation doses. In fact, using PML with certain parameter values results in better images, acquired using 2 mGy dose, than FBP-reconstructed images acquired using 6 mGy dose.Conclusions: A range of optimal free parameters for the PML algorithm with hyperbolic and TV norm-based potentials is presented for the microcalcification detection task, in dedicated breast CT. The reported values can be used as starting values of the free parameters, when SIR techniques are used for image reconstruction. Significant improvement in image quality can be achieved by using PML with optimal combination of parameters, as compared to FBP. Importantly, these results suggest improved detection of microcalcifications can be obtained by using PML with lower radiation dose to the patient, than using FBP with higher dose.

  20. SU-E-J-43: Deformed Planning CT as An Electron Density Substitute for Cone-Beam CT

    SciTech Connect (OSTI)

    Mishra, K; Godley, A

    2014-06-01

    Purpose: To confirm that deforming the planning CT to the daily Cone-Beam CTs (CBCT) can provide suitable electron density for adaptive planning. We quantify the dosimetric difference between plans calculated on deformed planning CTs (DPCT) and daily CT-on-rails images (CTOR). CTOR is used as a test of the method as CTOR already contains accurate electron density to compare against. Methods: Five prostate only IMRT patients, each with five CTOR images, were selected and re-planned on Panther (Prowess Inc.) with a uniform 5 mm PTV expansion, prescribed 78 Gy. The planning CT was deformed to match each CTOR using ABAS (Elekta Inc.). Contours were drawn on the CTOR, and copied to the DPCT. The original treatment plan was copied to both the CTOR and DPCT, keeping the center of the prostate as the isocenter. The plans were then calculated using the collapsed cone heterogeneous dose engine of Prowess and typical DVH planning parameters used to compare them. Results: Each DPCT was visually compared to its CTOR with no differences observed. The agreement of the copied CTOR contours with the DPCT anatomy further demonstrated the deformation accuracy. The plans calculated using CTOR and DPCT were compared. Over the 25 plan pairs, the average difference between them for prostate D100, D98 and D95 were 0.5%, 0.2%, and 0.2%; PTV D98, D95 and mean dose: 0.3%, 0.2% and 0.3%; bladder V70, V60 and mean dose: 1.1%, 0.7%, and 0.2%; and rectum mean dose: 0.3%. (D100 is the dose covering 100% of the target; V70 is the volume of the organ receiving 70 Gy). Conclusion: We observe negligible difference between the dose calculated on the DPCT and the CTOR, implying that deformed planning CTs are a suitable substitute for electron density. The method can now be applied to CBCTs. Research version of Panther provided by Prowess Inc. Research version of ABAS provided by Elekta Inc.

  1. Comparison of Image Registration Based Measures of Regional Lung Ventilation from Dynamic Spiral CT with Xe-CT

    E-Print Network [OSTI]

    Ding, Kai; Fuld, Matthew K; Du, Kaifang; Christensen, Gary E; Hoffman, Eric A; Reinhardt, Joseph M

    2012-01-01

    Purpose: Regional lung volume change as a function of lung inflation serves as an index of parenchymal and airway status as well as an index of regional ventilation and can be used to detect pathologic changes over time. In this article, we propose a new regional measure of lung mechanics --- the specific air volume change by corrected Jacobian. Methods: 4DCT and Xe-CT data sets from four adult sheep are used in this study. Nonlinear, 3D image registration is applied to register an image acquired near end inspiration to an image acquired near end expiration. Approximately 200 annotated anatomical points are used as landmarks to evaluate registration accuracy. Three different registration-based measures of regional lung mechanics are derived and compared: the specific air volume change calculated from the Jacobian (SAJ); the specific air volume change calculated by the corrected Jacobian (SACJ); and the specific air volume change by intensity change (SAI). Results: After registration, the mean registration err...

  2. Patient dose estimation from CT scans at the Mexican National Neurology and Neurosurgery Institute

    SciTech Connect (OSTI)

    Alva-Sánchez, Héctor

    2014-11-07

    In the radiology department of the Mexican National Institute of Neurology and Neurosurgery, a dedicated institute in Mexico City, on average 19.3 computed tomography (CT) examinations are performed daily on hospitalized patients for neurological disease diagnosis, control scans and follow-up imaging. The purpose of this work was to estimate the effective dose received by hospitalized patients who underwent a diagnostic CT scan using typical effective dose values for all CT types and to obtain the estimated effective dose distributions received by surgical and non-surgical patients. Effective patient doses were estimated from values per study type reported in the applications guide provided by the scanner manufacturer. This retrospective study included all hospitalized patients who underwent a diagnostic CT scan between 1 January 2011 and 31 December 2012. A total of 8777 CT scans were performed in this two-year period. Simple brain scan was the CT type performed the most (74.3%) followed by contrasted brain scan (6.1%) and head angiotomography (5.7%). The average number of CT scans per patient was 2.83; the average effective dose per patient was 7.9 mSv; the mean estimated radiation dose was significantly higher for surgical (9.1 mSv) than non-surgical patients (6.0 mSv). Three percent of the patients had 10 or more brain CT scans and exceeded the organ radiation dose threshold set by the International Commission on Radiological Protection for deterministic effects of the eye-lens. Although radiation patient doses from CT scans were in general relatively low, 187 patients received a high effective dose (>20 mSv) and 3% might develop cataract from cumulative doses to the eye lens.

  3. Subscribe / Give a Gift / Customer Service / Promotions / Blogs / Video / Digital Edition / JOIN FREE / SIGN IN TRY: Hottest Cars Ever / MINI Cooper / Best Gadgets Ever

    E-Print Network [OSTI]

    Romps, David M.

    / Digital Edition / JOIN FREE / SIGN IN TRY: Hottest Cars Ever / MINI Cooper / Best Sports Cars of the '70s and '80s From the 1970s through the mid-1980s, nearly every new sports car had a pointy nose and pop-up headlamps... CONNECT WITH POPULAR MECHANICS: FEATURED

  4. Iterative image-domain decomposition for dual-energy CT

    SciTech Connect (OSTI)

    Niu, Tianye; Dong, Xue; Petrongolo, Michael; Zhu, Lei

    2014-04-15

    Purpose: Dual energy CT (DECT) imaging plays an important role in advanced imaging applications due to its capability of material decomposition. Direct decomposition via matrix inversion suffers from significant degradation of image signal-to-noise ratios, which reduces clinical values of DECT. Existing denoising algorithms achieve suboptimal performance since they suppress image noise either before or after the decomposition and do not fully explore the noise statistical properties of the decomposition process. In this work, the authors propose an iterative image-domain decomposition method for noise suppression in DECT, using the full variance-covariance matrix of the decomposed images. Methods: The proposed algorithm is formulated in the form of least-square estimation with smoothness regularization. Based on the design principles of a best linear unbiased estimator, the authors include the inverse of the estimated variance-covariance matrix of the decomposed images as the penalty weight in the least-square term. The regularization term enforces the image smoothness by calculating the square sum of neighboring pixel value differences. To retain the boundary sharpness of the decomposed images, the authors detect the edges in the CT images before decomposition. These edge pixels have small weights in the calculation of the regularization term. Distinct from the existing denoising algorithms applied on the images before or after decomposition, the method has an iterative process for noise suppression, with decomposition performed in each iteration. The authors implement the proposed algorithm using a standard conjugate gradient algorithm. The method performance is evaluated using an evaluation phantom (Catphan©600) and an anthropomorphic head phantom. The results are compared with those generated using direct matrix inversion with no noise suppression, a denoising method applied on the decomposed images, and an existing algorithm with similar formulation as the proposed method but with an edge-preserving regularization term. Results: On the Catphan phantom, the method maintains the same spatial resolution on the decomposed images as that of the CT images before decomposition (8 pairs/cm) while significantly reducing their noise standard deviation. Compared to that obtained by the direct matrix inversion, the noise standard deviation in the images decomposed by the proposed algorithm is reduced by over 98%. Without considering the noise correlation properties in the formulation, the denoising scheme degrades the spatial resolution to 6 pairs/cm for the same level of noise suppression. Compared to the edge-preserving algorithm, the method achieves better low-contrast detectability. A quantitative study is performed on the contrast-rod slice of Catphan phantom. The proposed method achieves lower electron density measurement error as compared to that by the direct matrix inversion, and significantly reduces the error variation by over 97%. On the head phantom, the method reduces the noise standard deviation of decomposed images by over 97% without blurring the sinus structures. Conclusions: The authors propose an iterative image-domain decomposition method for DECT. The method combines noise suppression and material decomposition into an iterative process and achieves both goals simultaneously. By exploring the full variance-covariance properties of the decomposed images and utilizing the edge predetection, the proposed algorithm shows superior performance on noise suppression with high image spatial resolution and low-contrast detectability.

  5. Silben Workshop Mnster, 2011 Christine Mooshammer, Haskins Labs, New Haven, CT

    E-Print Network [OSTI]

    , MA) Elliot Saltzman (Haskins & BU, Boston, MA) Hosung Nam (Haskins) Argyo Katsika (Haskins & Yale, CT und Elliot Saltzman) Grundlegende Einheit in der gesprochenen Sprache sind die Gesten Gesten werden

  6. Low-Dose Spiral CT Scans for Early Lung Cancer Detection

    Broader source: Energy.gov [DOE]

    Low-dose spiral computed tomography (CT) scanning is a noninvasive medical imaging test that has been used for the early detection of lung cancer for over 16 years (Sone et al. 1998; Henschke et.al. 1999).

  7. Frequency and patterns of abnormality detected by iodine-123 amine emission CT after cerebral infarction

    SciTech Connect (OSTI)

    Brott, T.G.; Gelfand, M.J.; Williams, C.C.; Spilker, J.A.; Hertzberg, V.S.

    1986-03-01

    Single photon emission computed tomography (SPECT) was performed in 31 patients with cerebral infarction and 13 who had had transient ischemic attacks, using iodine-123-labeled N,N,N'-trimethyl-N'-(2-hydroxyl-3-methyl-5-iodobenzyl)-1,3-propanediamin e (I-123-HIPDM) as the radiopharmaceutical. SPECT scans were compared with computed tomographic (CT) scans. SPECT was as sensitive as CT in detecting cerebral infarction (94% vs. 84%). The abnormalities were larger on the SPECT scans than on the CT scans in 19 cases, equal in seven, and smaller in five (SPECT abnormalities greater than or equal to CT abnormalities in 86% of cases). Fifteen of 30 patients with hemispheric infarction had decreased perfusion (decreased uptake of I-123-HIPDM) to the cerebellar hemisphere contralateral to the cerebral hemisphere involved by the infarction (crossed cerebellar diaschisis). Nine of these 15 patients had major motor deficits, while only one of the 15 without crossed cerebellar diaschisis had a major motor deficit.

  8. 10 A.M. CT TODAY: On-the Record Conference Call for Obama Administrati...

    Broader source: Energy.gov (indexed) [DOE]

    White House Rural Economic Council Promotes Production of Next Generation Biofuels, Job Creation and Economic Opportunity WASHINGTON, Aug. 16, 2011 - Today at 10 a.m. CT (11 a.m....

  9. Finite Element Analysis of Ballistic Penetration of Plain Weave Twaron CT709® Fabrics: A Parametric Study 

    E-Print Network [OSTI]

    Gogineni, Sireesha

    2011-10-21

    The ballistic impact of Twaron CT709® plain weave fabrics is studied using an explicit finite element method. Many existing approximations pertaining to woven fabrics cannot adequately represent strain rate-dependent behavior exhibited by the Twaron...

  10. Lung nodule detection in low-dose and high-resolution CT scans

    E-Print Network [OSTI]

    Delogu, P; Gori, I; Preite Martínez, A; Retico, A; Tata, A

    2006-01-01

    We are developing a computer-aided detection (CAD) system for the identification of small pulmonary nodules in screening CT scans. The main modules of our system, i.e. a dot-enhancement filter for nodule candidate selection and a neural classifier for false positive finding reduction, are described. The preliminary results obtained on the so-far collected database of lung CT are discussed.

  11. The effects of mapping CT images to Monte Carlo materials on GEANT4 proton simulation accuracy

    SciTech Connect (OSTI)

    Barnes, Samuel; McAuley, Grant; Slater, James; Wroe, Andrew

    2013-04-15

    Purpose: Monte Carlo simulations of radiation therapy require conversion from Hounsfield units (HU) in CT images to an exact tissue composition and density. The number of discrete densities (or density bins) used in this mapping affects the simulation accuracy, execution time, and memory usage in GEANT4 and other Monte Carlo code. The relationship between the number of density bins and CT noise was examined in general for all simulations that use HU conversion to density. Additionally, the effect of this on simulation accuracy was examined for proton radiation. Methods: Relative uncertainty from CT noise was compared with uncertainty from density binning to determine an upper limit on the number of density bins required in the presence of CT noise. Error propagation analysis was also performed on continuously slowing down approximation range calculations to determine the proton range uncertainty caused by density binning. These results were verified with Monte Carlo simulations. Results: In the presence of even modest CT noise (5 HU or 0.5%) 450 density bins were found to only cause a 5% increase in the density uncertainty (i.e., 95% of density uncertainty from CT noise, 5% from binning). Larger numbers of density bins are not required as CT noise will prevent increased density accuracy; this applies across all types of Monte Carlo simulations. Examining uncertainty in proton range, only 127 density bins are required for a proton range error of <0.1 mm in most tissue and <0.5 mm in low density tissue (e.g., lung). Conclusions: By considering CT noise and actual range uncertainty, the number of required density bins can be restricted to a very modest 127 depending on the application. Reducing the number of density bins provides large memory and execution time savings in GEANT4 and other Monte Carlo packages.

  12. Semi-automatic delineation using weighted CT-MRI registered images for radiotherapy of nasopharyngeal cancer

    SciTech Connect (OSTI)

    Fitton, I. [European Georges Pompidou Hospital, Department of Radiology, 20 rue Leblanc, 75015, Paris (France); Cornelissen, S. A. P. [Image Sciences Institute, UMC, Department of Radiology, P.O. Box 85500, 3508 GA Utrecht (Netherlands); Duppen, J. C.; Rasch, C. R. N.; Herk, M. van [The Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Department of Radiotherapy, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands); Steenbakkers, R. J. H. M. [University Medical Center Groningen, Department of Radiation Oncology, Hanzeplein 1, 9713 GZ Groningen (Netherlands); Peeters, S. T. H. [UZ Gasthuisberg, Herestraat 49, 3000 Leuven, Belgique (Belgium); Hoebers, F. J. P. [Maastricht University Medical Center, Department of Radiation Oncology (MAASTRO clinic), GROW School for Oncology and Development Biology Maastricht, 6229 ET Maastricht (Netherlands); Kaanders, J. H. A. M. [UMC St-Radboud, Department of Radiotherapy, Geert Grooteplein 32, 6525 GA Nijmegen (Netherlands); Nowak, P. J. C. M. [ERASMUS University Medical Center, Department of Radiation Oncology,Groene Hilledijk 301, 3075 EA Rotterdam (Netherlands)

    2011-08-15

    Purpose: To develop a delineation tool that refines physician-drawn contours of the gross tumor volume (GTV) in nasopharynx cancer, using combined pixel value information from x-ray computed tomography (CT) and magnetic resonance imaging (MRI) during delineation. Methods: Operator-guided delineation assisted by a so-called ''snake'' algorithm was applied on weighted CT-MRI registered images. The physician delineates a rough tumor contour that is continuously adjusted by the snake algorithm using the underlying image characteristics. The algorithm was evaluated on five nasopharyngeal cancer patients. Different linear weightings CT and MRI were tested as input for the snake algorithm and compared according to contrast and tumor to noise ratio (TNR). The semi-automatic delineation was compared with manual contouring by seven experienced radiation oncologists. Results: A good compromise for TNR and contrast was obtained by weighing CT twice as strong as MRI. The new algorithm did not notably reduce interobserver variability, it did however, reduce the average delineation time by 6 min per case. Conclusions: The authors developed a user-driven tool for delineation and correction based a snake algorithm and registered weighted CT image and MRI. The algorithm adds morphological information from CT during the delineation on MRI and accelerates the delineation task.

  13. Dose uncertainty due to computed tomography ,,CT... slice thickness in CT-based high dose rate brachytherapy of the prostate cancer

    E-Print Network [OSTI]

    Pouliot, Jean

    brachytherapy of the prostate cancer Yongbok Kim,a) I-Chow Joe Hsu, Etienne Lessard, and Jean Pouliot Department tomography CT -based high dose rate HDR brachytherapy, the uncertainty in the localization in Medicine. DOI: 10.1118/1.1785454 Key words: high dose rate brachytherapy, computed tomography, prostate

  14. Synergetic effects of II-VI sensitization upon TiO{sub 2} for photoelectrochemical water splitting; a tri-layered structured scheme

    SciTech Connect (OSTI)

    Mumtaz, Asad, E-mail: asad-032@yahoo.com [Department of Fundamental and Applied Sciences, University Teknologi PETRONAS (Malaysia); Mohamed, Norani Muti, E-mail: noranimuti-mohamed@petronas.com.my [Centre of Innovative Nanostructures and Nanodevices (COINN), Universiti Teknologi PETRONAS (Malaysia)

    2014-10-24

    World's energy demands are growing on a higher scale increasing the need of more reliable and long term renewable energy resources. Efficient photo-electrochemical (PEC) devices based on novel nano-structured designs for solar-hydrogen generation need to be developed. This study provides an insight of the tri-layered-TiO2 based nanostructures. Observing the mechanism of hydrogen production, the comparison of the structural order during the synthesis is pronounced. The sequence in the tri-layered structure affects the photogenerated electron (e{sup ?}) and hole (h{sup +}) pair transfer and separation. It is also discussed that not only the semiconductors band gaps alignment is important with respect to the water redox potential but also the interfacial regions. Quasi-Fermi-level adjustment at the interfacial regions plays a key role in deciding the solar to hydrogen efficiency. More efficient multicomponent semiconductor nano-design (MCSN) could be developed with the approach given in this study.

  15. A review of "Alchemy Tried in the Fire: Starkey, Boyle, and the Fate of Helmontian Chymistry." by William R. Newman and Lawrence M. Principe 

    E-Print Network [OSTI]

    Luciano Boschiero

    2003-01-01

    James Ver- sion. Because both these books positively invite such participation and such questions, both are good ?machines for thinking with.? William R. Newman and Lawrence M. Principe. Alchemy Tried in the Fire: Starkey, Boyle, and the Fate...? With the help of some important manuscript sources, Newman and Principe offer some enlightening answers to these questions. Through the laboratory notes of seventeenth-century American alchemist, George Starkey, these authors provide a rare insight...

  16. MO-E-17A-03: Monte Carlo CT Dose Calculation: A Comparison Between Experiment and Simulation Using ARCHER-CT

    SciTech Connect (OSTI)

    Liu, T; Du, X; Su, L; Gao, Y; Ji, W; Xu, X; Zhang, D; Shi, J; Liu, B; Kalra, M

    2014-06-15

    Purpose: To compare the CT doses derived from the experiments and GPU-based Monte Carlo (MC) simulations, using a human cadaver and ATOM phantom. Methods: The cadaver of an 88-year old male and the ATOM phantom were scanned by a GE LightSpeed Pro 16 MDCT. For the cadaver study, the Thimble chambers (Model 10×5?0.6CT and 10×6?0.6CT) were used to measure the absorbed dose in different deep and superficial organs. Whole-body scans were first performed to construct a complete image database for MC simulations. Abdomen/pelvis helical scans were then conducted using 120/100 kVps, 300 mAs and a pitch factor of 1.375:1. For the ATOM phantom study, the OSL dosimeters were used and helical scans were performed using 120 kVp and x, y, z tube current modulation (TCM). For the MC simulations, sufficient particles were run in both cases such that the statistical errors of the results by ARCHER-CT were limited to 1%. Results: For the human cadaver scan, the doses to the stomach, liver, colon, left kidney, pancreas and urinary bladder were compared. The difference between experiments and simulations was within 19% for the 120 kVp and 25% for the 100 kVp. For the ATOM phantom scan, the doses to the lung, thyroid, esophagus, heart, stomach, liver, spleen, kidneys and thymus were compared. The difference was 39.2% for the esophagus, and within 16% for all other organs. Conclusion: In this study the experimental and simulated CT doses were compared. Their difference is primarily attributed to the systematic errors of the MC simulations, including the accuracy of the bowtie filter modeling, and the algorithm to generate voxelized phantom from DICOM images. The experimental error is considered small and may arise from the dosimeters. R01 grant (R01EB015478) from National Institute of Biomedical Imaging and Bioengineering.

  17. The visual binary AG Tri in $\\beta$ Pictoris Association: can a debris disc cause very different rotation periods of its components?

    E-Print Network [OSTI]

    Messina, Sergio; Artemenko, Svetlana; Bailey, John I; Savushkin, Alexander; Nelson, Robert H

    2015-01-01

    We measure the photometric rotation periods of the components of multiple systems in young stellar associations to investigate the causes of the observed rotation period dispersion. We present the case of the wide binary AG Tri in the 23-Myr young beta Pictoris Association consisting of K4 + M1 dwarfs. Our multi-band, multi-season photometric monitoring allowed us to measure the rotation periods of both components P_A = 12.4d and P_B = 4.66d, to detect a prominent magnetic activity in the photosphere, likely responsible for the measured radial velocity variations, and for the first time, a flare event on the M1 component AG Tri B. We investigate either the possibility that the faster rotating component may have suffered an enhanced primordial disc dispersal, starting its PMS spin-up earlier than the slower rotating component, or the possibility that the formation of a debris disc may have prevented AG Tri A from gaining part of the angular momentum from the accreting disc.

  18. Estimated cumulative radiation dose from PET/CT in children with malignancies: a 5-year retrospective review

    E-Print Network [OSTI]

    2010-01-01

    both PET and CT studies. The ALARA principle must be appliedprotocols that follow the ALARA principle (as low asis necessary to apply the ALARA principle in the radiation

  19. SU-E-I-68: Practical Considerations On Implementation of the Image Gently Pediatric CT Protocols

    SciTech Connect (OSTI)

    Zhang, J; Adams, C; Lumby, C; Dillon, J [University of Kentucky, Lexington, KY (United States); Woods, E [University of kentucky, Lexington, KY (United States); Richer, E [University of Kentucky, Lexington, Lexington (United States)

    2014-06-01

    Purpose: One limitation associated with the Image Gently pediatric CT protocols is practical implementation of the recommended manual techniques. Inconsistency as a result of different practice is a possibility among technologist. An additional concern is the added risk of data error that would result in over or underexposure. The Automatic Exposure Control (AEC) features automatically reduce radiation for children. However, they do not work efficiently for the patients of very small size and relative large size. This study aims to implement the Image Gently pediatric CT protocols in the practical setting while maintaining the use of AEC features for pediatric patients of varying size. Methods: Anthropomorphological abdomen phantoms were scanned in a CT scanner using the Image Gently pediatric protocols, the AEC technique with a fixed adult baseline, and automatic protocols with various baselines. The baselines were adjusted corresponding to patient age, weight and posterioranterior thickness to match the Image Gently pediatric CT manual techniques. CTDIvol was recorded for each examination. Image noise was measured and recorded for image quality comparison. Clinical images were evaluated by pediatric radiologists. Results: By adjusting vendor default baselines used in the automatic techniques, radiation dose and image quality can match those of the Image Gently manual techniques. In practice, this can be achieved by dividing pediatric patients into three major groups for technologist reference: infant, small child, and large child. Further division can be done but will increase the number of CT protocols. For each group, AEC can efficiently adjust acquisition techniques for children. This implementation significantly overcomes the limitation of the Image Gently manual techniques. Conclusion: Considering the effectiveness in clinical practice, Image Gently Pediatric CT protocols can be implemented in accordance with AEC techniques, with adjusted baselines, to achieve the goal of providing the most appropriate radiation dose for pediatric patients of varying sizes.

  20. Resolution enhancement of lung 4D-CT data using multiscale interphase iterative nonlocal means

    SciTech Connect (OSTI)

    Zhang Yu [School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China and Department of Radiology and BRIC, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Yap, Pew-Thian; Wu Guorong [Department of Radiology and BRIC, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Feng Qianjin; Chen Wufan [School of Biomedical Engineering, Southern Medical University, Guangzhou 510515 (China); Lian Jun [Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Shen Dinggang [Department of Radiology and BRIC, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Department of Brain and Cognitive Engineering, Korea University, Seoul 136-713 (Korea, Republic of)

    2013-05-15

    Purpose: Four-dimensional computer tomography (4D-CT) has been widely used in lung cancer radiotherapy due to its capability in providing important tumor motion information. However, the prolonged scanning duration required by 4D-CT causes considerable increase in radiation dose. To minimize the radiation-related health risk, radiation dose is often reduced at the expense of interslice spatial resolution. However, inadequate resolution in 4D-CT causes artifacts and increases uncertainty in tumor localization, which eventually results in extra damages of healthy tissues during radiotherapy. In this paper, the authors propose a novel postprocessing algorithm to enhance the resolution of lung 4D-CT data. Methods: The authors' premise is that anatomical information missing in one phase can be recovered from the complementary information embedded in other phases. The authors employ a patch-based mechanism to propagate information across phases for the reconstruction of intermediate slices in the longitudinal direction, where resolution is normally the lowest. Specifically, the structurally matching and spatially nearby patches are combined for reconstruction of each patch. For greater sensitivity to anatomical details, the authors employ a quad-tree technique to adaptively partition the image for more fine-grained refinement. The authors further devise an iterative strategy for significant enhancement of anatomical details. Results: The authors evaluated their algorithm using a publicly available lung data that consist of 10 4D-CT cases. The authors' algorithm gives very promising results with significantly enhanced image structures and much less artifacts. Quantitative analysis shows that the authors' algorithm increases peak signal-to-noise ratio by 3-4 dB and the structural similarity index by 3%-5% when compared with the standard interpolation-based algorithms. Conclusions: The authors have developed a new algorithm to improve the resolution of 4D-CT. It outperforms the conventional interpolation-based approaches by producing images with the markedly improved structural clarity and greatly reduced artifacts.

  1. Resolution enhancement of lung 4D-CT via group-sparsity

    SciTech Connect (OSTI)

    Bhavsar, Arnav; Wu, Guorong; Shen, Dinggang [Department of Radiology and BRIC, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)] [Department of Radiology and BRIC, University of North Carolina, Chapel Hill, North Carolina 27599 (United States); Lian, Jun [Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)] [Department of Radiation Oncology, University of North Carolina, Chapel Hill, North Carolina 27599 (United States)

    2013-12-15

    Purpose: 4D-CT typically delivers more accurate information about anatomical structures in the lung, over 3D-CT, due to its ability to capture visual information of the lung motion across different respiratory phases. This helps to better determine the dose during radiation therapy for lung cancer. However, a critical concern with 4D-CT that substantially compromises this advantage is the low superior-inferior resolution due to less number of acquired slices, in order to control the CT radiation dose. To address this limitation, the authors propose an approach to reconstruct missing intermediate slices, so as to improve the superior-inferior resolution.Methods: In this method the authors exploit the observation that sampling information across respiratory phases in 4D-CT can be complimentary due to lung motion. The authors’ approach uses this locally complimentary information across phases in a patch-based sparse-representation framework. Moreover, unlike some recent approaches that treat local patches independently, the authors’ approach employs the group-sparsity framework that imposes neighborhood and similarity constraints between patches. This helps in mitigating the trade-off between noise robustness and structure preservation, which is an important consideration in resolution enhancement. The authors discuss the regularizing ability of group-sparsity, which helps in reducing the effect of noise and enables better structural localization and enhancement.Results: The authors perform extensive experiments on the publicly available DIR-Lab Lung 4D-CT dataset [R. Castillo, E. Castillo, R. Guerra, V. Johnson, T. McPhail, A. Garg, and T. Guerrero, “A framework for evaluation of deformable image registration spatial accuracy using large landmark point sets,” Phys. Med. Biol. 54, 1849–1870 (2009)]. First, the authors carry out empirical parametric analysis of some important parameters in their approach. The authors then demonstrate, qualitatively as well as quantitatively, the ability of their approach to achieve more accurate and better localized results over bicubic interpolation as well as a related state-of-the-art approach. The authors also show results on some datasets with tumor, to further emphasize the clinical importance of their method.Conclusions: The authors have proposed to improve the superior-inferior resolution of 4D-CT by estimating intermediate slices. The authors’ approach exploits neighboring constraints in the group-sparsity framework, toward the goal of achieving better localization and noise robustness. The authors’ results are encouraging, and positively demonstrate the role of group-sparsity for 4D-CT resolution enhancement.

  2. 1682 IEEE TRANSACTIONS ON MEDICAL IMAGING, VOL. 31, NO. 9, SEPTEMBER 2012 Low-Dose X-ray CT Reconstruction

    E-Print Network [OSTI]

    Wang, Ge

    1682 IEEE TRANSACTIONS ON MEDICAL IMAGING, VOL. 31, NO. 9, SEPTEMBER 2012 Low-Dose X-ray CT and other diseases. How to reduce radiation dose while maintaining the diagnostic per- formance is a major- straint in terms of total variation (TV) minimization has already led to promising results for low-dose CT

  3. Database-Assisted Low-Dose CT Image Restoration Wei Xu, Sungsoo Ha and Klaus Mueller, Senior Member, IEEE

    E-Print Network [OSTI]

    Database-Assisted Low-Dose CT Image Restoration Wei Xu, Sungsoo Ha and Klaus Mueller, Senior Member, IEEE Abstract­ The image quality of low-dose CT scans typically suffers greatly from the limited utilization of X-ray radiation. Although the harmful effects to patient health are reduced, the low quality

  4. Manifold Learning for 4D CT Reconstruction of the Lung Manfred Georg*, Richard Souvenir, Andrew Hope, Robert Pless*

    E-Print Network [OSTI]

    Pless, Robert

    Manifold Learning for 4D CT Reconstruction of the Lung Manfred Georg*, Richard Souvenir, Andrew, Canada Andrew.Hope@rmp.uhn.on.ca Abstract Computed Tomography is used to create models of lung dynamics because it provides high contrast images of lung tissue. Creating 4D CT models which capture dynamics

  5. USPSTF Recommends Low-Dose CT Screening for Heavy Smoke Published on Cancer Network (http://www.cancernetwork.com)

    E-Print Network [OSTI]

    Serfling, Robert

    remains the leading cause of cancer death in the United States, and is the third most common of all radiography, and found an overall reduction in death from any cause in the CT group of 6.7% (95% CI, 1, lie largely in the high rates of false positives. A total of 96.4% of the positive low-dose CT results

  6. TriBITS lifecycle model. Version 1.0, a lean/agile software lifecycle model for research-based computational science and engineering and applied mathematical software.

    SciTech Connect (OSTI)

    Willenbring, James M.; Bartlett, Roscoe Ainsworth; Heroux, Michael Allen

    2012-01-01

    Software lifecycles are becoming an increasingly important issue for computational science and engineering (CSE) software. The process by which a piece of CSE software begins life as a set of research requirements and then matures into a trusted high-quality capability is both commonplace and extremely challenging. Although an implicit lifecycle is obviously being used in any effort, the challenges of this process - respecting the competing needs of research vs. production - cannot be overstated. Here we describe a proposal for a well-defined software lifecycle process based on modern Lean/Agile software engineering principles. What we propose is appropriate for many CSE software projects that are initially heavily focused on research but also are expected to eventually produce usable high-quality capabilities. The model is related to TriBITS, a build, integration and testing system, which serves as a strong foundation for this lifecycle model, and aspects of this lifecycle model are ingrained in the TriBITS system. Here, we advocate three to four phases or maturity levels that address the appropriate handling of many issues associated with the transition from research to production software. The goals of this lifecycle model are to better communicate maturity levels with customers and to help to identify and promote Software Engineering (SE) practices that will help to improve productivity and produce better software. An important collection of software in this domain is Trilinos, which is used as the motivation and the initial target for this lifecycle model. However, many other related and similar CSE (and non-CSE) software projects can also make good use of this lifecycle model, especially those that use the TriBITS system. Indeed this lifecycle process, if followed, will enable large-scale sustainable integration of many complex CSE software efforts across several institutions.

  7. Does dual-energy CT of lower-extremity tendons incur penalties in patient radiation exposure or reduced multiplanar reconstruction image quality?

    E-Print Network [OSTI]

    2008-01-01

    diagnostic value of dual-energy CT and MRI in the detectionusing dual-source dual-energy MDCT: Results of JAFROCfor dose reduction in dual energy hepatic CT using non-

  8. 6.13 Greenhouse Climates M Pagani, Yale University, New Haven, CT, USA

    E-Print Network [OSTI]

    6.13 Greenhouse Climates M Pagani, Yale University, New Haven, CT, USA M Huber, Purdue University Hyperthermals 284 6.13.4 The Case For and Against Glaciations During Greenhouse Climates 286 6.13.5 Greenhouse Climates and Organic Carbon Burial 288 6.13.6 Climate Modeling and the Challenges of Greenhouse Temperature

  9. VERY BASIC LIE THEORY Department of Mathematics, Yale University, New Haven, CT 06520

    E-Print Network [OSTI]

    Berenstein, Arkady

    VERY BASIC LIE THEORY ROGER HOWE Department of Mathematics, Yale University, New Haven, CT 06520 Lie theory, the theory of Lie groups, Lie algebras and their applications, is a fundamental part variables), group and ring theory, number theory, and physics, from classical to quantum and relativistic

  10. SCIPP 06/04 1 Prototype Tracking Studies for Proton CT

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    SCIPP 06/04 1 Prototype Tracking Studies for Proton CT Nate Blumenkrantz, Jason Feldt, Jason the feasibility of proton computed tomography, the most likely path (MLP) of protons inside an absorber resolution. The locations of 200 MeV protons were measured at three different absorber depth of PMMA (3.75, 6

  11. 3501 FR.03 C&T and M&P Employee Record Completion Prepared by

    E-Print Network [OSTI]

    Post, David M.

    3501 FR.03 C&T and M&P Employee Record Completion Prepared by: name department phone date Authorized by: name title signature date Employee: Effective Date: last name first name m.i. Social Security form Home Address Additional Address Details Flexfield >Enter directory listing preference (default

  12. Vertex2002 pCT: Hartmut F.-W. Sadrozinski , SCIPP Initial Studies in Proton Computed

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    =>Energy to better than % · Improve energy determination with statistics 52 2 ~D A N D d. Shahnazi Loma Linda University Medical Center, Loma Linda, CA 92354 · Proton Energy Loss in Matter · Proton Detector array · Proton CT replaces X-ray absorption with proton energy loss to reconstruct mass density

  13. Towards robust deconvolution of low-dose perfusion CT: Sparse perfusion deconvolution using online dictionary learning

    E-Print Network [OSTI]

    Chen, Tsuhan

    in CTP performed at low radiation dose. We first build a dictionary from high-dose perfusion maps usingTowards robust deconvolution of low-dose perfusion CT: Sparse perfusion deconvolution using online maps of blood flow tend to be noisy, especially in low-dose CTP, due to the noisy contrast enhancement

  14. Multi-Material Decomposition Using Statistical Image Reconstruction in X-Ray CT

    E-Print Network [OSTI]

    Fessler, Jeffrey A.

    propose a penalized- likelihood (PL) method with edge-preserving regularizers for each material image reconstruction I. INTRODUCTION Dual-energy (DE) CT reconstruction methods typically re- construct. It obtains a dual-material-density pair through projection-based decomposition approach from DECT

  15. Computer modeling of the spatial resolution properties of a dedicated breast CT system

    SciTech Connect (OSTI)

    Yang Kai; Kwan, Alexander L. C.; Boone, John M. [Department of Radiology, University of California, Davis Medical Center, 4860 Y Street, Suite 3100 Ellison Building, Sacramento, California 95817 (United States) and Department of Biomedical Engineering, University of California, Davis, California, 95616 (United States); Department of Radiology, University of California, Davis Medical Center, 4860 Y Street, Suite 3100 Ellison Building, Sacramento, California 95817 (United States); Department of Radiology, University of California, Davis Medical Center, 4860 Y Street, Suite 3100 Ellison Building, Sacramento, California 95817 (United States) and Department of Biomedical Engineering, University of California, Davis, California 95616 (United States)

    2007-06-15

    Computer simulation methods were used to evaluate the spatial resolution properties of a dedicated cone-beam breast CT system. x-ray projection data of a 70 {mu}m nickel-chromium wire were simulated. The modulation transfer function (MTF) was calculated from the reconstructed axial images at different radial positions from the isocenter to study the spatial dependency of the spatial resolution of the breast CT scanner. The MTF was also calculated in both the radial and azimuthal directions. Subcomponents of the cone beam CT system that affect the MTF were modeled in the computer simulation in a serial manner, including the x-ray focal spot distribution, gantry rotation under the condition of continuous fluoroscopy, detector lag, and detector spatial resolution. Comparison between the computer simulated and physically measured MTF values demonstrates reasonable accuracy in the simulation process, with a small systematic difference ({approx}9.5{+-}6.4% difference, due to unavoidable uncertainties from physical measurement and system calibration). The intrinsic resolution in the radial direction determined by simulation was about 2.0 mm{sup -1} uniformly through the field of view. The intrinsic resolution in the azimuthal direction degrades from 2.0 mm{sup -1} at the isocenter to 1.0 mm{sup -1} at the periphery with 76.9 mm from the isocenter. The results elucidate the intrinsic spatial resolution properties of the prototype breast CT system, and suggest ways in which spatial resolution can be improved with system modification.

  16. Volume Estimation and Surgery Planning from Lung CT Images ANA ELISA FERREIRA SCHMIDT

    E-Print Network [OSTI]

    Volume Estimation and Surgery Planning from Lung CT Images ANA ELISA FERREIRA SCHMIDT 1 , PAULO to assist the planning of lung reduction surgeries, a technique that has been proposed for the treatment of certain illnesses. Doctors need to decide which portions of the lungs to remove to achieve a certain

  17. Technical Note: Measurement of bow tie profiles in CT scanners using radiochromic film

    SciTech Connect (OSTI)

    Whiting, Bruce R.; Dohatcu, Andreea C.; Evans, Joshua D.; Williamson, Jeffrey F.; Politte, David G.

    2015-06-15

    Purpose: To provide a noninvasive technique to measure the intensity profile of the fan beam in a computed tomography (CT) scanner that is cost effective and easily implemented without the need to access proprietary scanner information or service modes. Methods: The fabrication of an inexpensive aperture is described, which is used to expose radiochromic film in a rotating CT gantry. A series of exposures is made, each of which is digitized on a personal computer document scanner, and the resulting data set is analyzed to produce a self-consistent calibration of relative radiation exposure. The bow tie profiles were analyzed to determine the precision of the process and were compared to two other measurement techniques, direct measurements from CT gantry detectors and a dynamic dosimeter. Results: The radiochromic film method presented here can measure radiation exposures with a precision of ?6% root-mean-square relative error. The intensity profiles have a maximum 25% root-mean-square relative error compared with existing techniques. Conclusions: The proposed radiochromic film method for measuring bow tie profiles is an inexpensive (?$100 USD + film costs), noninvasive method to measure the fan beam intensity profile in CT scanners.

  18. Technical Reports Ultra-low Dose Lung CT Perfusion Regularized by

    E-Print Network [OSTI]

    Wang, Ge

    Technical Reports Ultra-low Dose Lung CT Perfusion Regularized by a Previous Scan1 Hengyong Yu, Ph­regularized reconstruction (PSRR) method was proposed to reduce radiation dose and applied to lung perfusion studies. Normal and ultra-low-dose lung computed tomographic perfusion studies were compared in terms of the estimation

  19. Multi-stage Learning for Robust Lung Segmentation in Challenging CT Volumes

    E-Print Network [OSTI]

    Multi-stage Learning for Robust Lung Segmentation in Challenging CT Volumes Michal Sofka1 , Jens Imaging, Siemens Healthcare, Oxford, UK Abstract. Simple algorithms for segmenting healthy lung parenchyma an ini- tialization of a statistical shape model of the lungs. The initialization first detects

  20. A Framework for Automatic Segmentation of Lung Nodules from Low Dose Chest CT Scans

    E-Print Network [OSTI]

    Louisville, University of

    A Framework for Automatic Segmentation of Lung Nodules from Low Dose Chest CT Scans Ayman El-Baz1 the high accuracy of the proposed approach. 1 Introduction Because lung cancer is the most common cause 1, an initial LDCT slice is segmented with our algorithms introduced in [3] to isolate lung tissues

  1. Automatic Lung Segmentation of Volumetric Low-Dose CT Scans Using Graph Cuts

    E-Print Network [OSTI]

    Louisville, University of

    Automatic Lung Segmentation of Volumetric Low-Dose CT Scans Using Graph Cuts Asem M. Ali and Aly A for unsupervised segmentation of the lung region from low dose computed tomography (LDCT) images. We follow distribution model. To better spec- ify region borders between lung and chest, each empirical distribution

  2. CLASSIFICATION OF BIOMEDICAL HIGH-RESOLUTION MICRO-CT IMAGES FOR DIRECT VOLUME RENDERING

    E-Print Network [OSTI]

    López-Sánchez, Maite

    CLASSIFICATION OF BIOMEDICAL HIGH-RESOLUTION MICRO-CT IMAGES FOR DIRECT VOLUME RENDERING Maite L of biomedical high- resolution 3D images. More concretely, it proposes a learn- ing pipeline process and refinements. KEYWORDS Machine Learning, Biomedical 3D Images, Classification, CRF (Conditional Random Fields

  3. Hydro-thermal flow in a rough fracture EC Contract SES6-CT-2003-502706

    E-Print Network [OSTI]

    Toussaint, Renaud

    Hydro-thermal flow in a rough fracture EC Contract SES6-CT-2003-502706 PARTICIPANT ORGANIZATION NAME: CNRS Synthetic 2nd year report Related with Work Package............ HYDRO-THERMAL FLOW in the influence of a realistic geometry of the fracture on its hydro-thermal response. Several studies have

  4. A Novel 3D Segmentation of Vertebral Bones from Volumetric CT Images Using Graph Cuts

    E-Print Network [OSTI]

    Farag, Aly A.

    of the vertebral bones of spine column with a particular focus on the lumbar spine. The primary goalA Novel 3D Segmentation of Vertebral Bones from Volumetric CT Images Using Graph Cuts Melih S to the Vertebral bodies (VBs). In this paper, we present a novel and fast 3D segmentation framework of VBs

  5. Leakage through Liners under High Hydraulic Heads C.T. Weber1

    E-Print Network [OSTI]

    Zornberg, Jorge G.

    of this project is to contribute towards the use of geosynthetics in the design of dams and other hydraulic of geomembrane and composite liners for hydraulic systems such as dams involves heads several hundreds largerLeakage through Liners under High Hydraulic Heads C.T. Weber1 and J.G. Zornberg2 1 Civil

  6. Automatic Lumbar Vertebra Segmentation from clinical CT for Wedge Compression Fracture Diagnosis

    E-Print Network [OSTI]

    Chaudhary, Vipin

    Automatic Lumbar Vertebra Segmentation from clinical CT for Wedge Compression Fracture Diagnosis, Williamsville, NY 14221 ABSTRACT Lumbar vertebral fractures vary greatly in types and causes and usually result from severe trauma or pathological conditions such as osteoporosis. Lumbar wedge compression fractures

  7. SU-E-I-58: Detecting Tumors with Extremely Low Contrast in CT Images

    SciTech Connect (OSTI)

    Sheng, K; Gou, S; Kupelian, P; Steiberg, M; Low, D

    2014-06-01

    Purpose: Tumors such as the prostate focal lesions and the brain metastases have extremely low CT contrast and MRI is usually used for target delineation. The target contours are propagated to the CT for treatment planning and patient positioning. We have employed an advanced denoising method eliminating the noise and allow magnification of subtle contrast of these focal lesions on CT. Methods: Five prostate and two brain metastasis patients with MRI T2, diffusion or dynamic contrast enhanced (DCE) images confirmed focal lesions were included. One brain patients had 5 metastases. A block matching 3D (BM3D) algorithm was adapted to reduce the noise of kVCT images used for treatment planning. The gray-level range of the resultant images was narrowed to magnify the tumor-normal tissue contrast. Results: For the prostate patients, denoised kVCT images showed focal regions at 5, 8,11-1, 2, and 8–10 oclock for the 5 patients, this is highly consistent to the radiologist confirmed focal lesions based on MRI at 5, 7, 11-1, 2 and 8–10 oclock in the axial plane. These CT focal regions matched well with the MRI focal lesions in the cranio-caudal position. The average increase in density compared to background prostate glands was 0.86%, which corresponds to ?50% increase in cellularity and is lower than the average CT noise level of 2.4%. For the brain patients, denoised kVCT showed 5/6 metastases. The high CT-density region of a metastasis is 2-mm off from its corresponding elevated MRI perfusion center. Overall the detecting sensitivity was 91%. Conclusion: It has been preliminarily demonstrated that the higher tumor cellularity can be detected using kVCT. The low contrast-to-noise information requires advanced denoising to reveal. The finding is significant to radiotherapy by providing an additional tool to locate focal lesions for confirming MRI-CT registration and providing a highly accessible outcome assessment tool.

  8. Statistical model based iterative reconstruction (MBIR) in clinical CT systems: Experimental assessment of noise performance

    SciTech Connect (OSTI)

    Li, Ke; Tang, Jie; Chen, Guang-Hong

    2014-04-15

    Purpose: To reduce radiation dose in CT imaging, the statistical model based iterative reconstruction (MBIR) method has been introduced for clinical use. Based on the principle of MBIR and its nonlinear nature, the noise performance of MBIR is expected to be different from that of the well-understood filtered backprojection (FBP) reconstruction method. The purpose of this work is to experimentally assess the unique noise characteristics of MBIR using a state-of-the-art clinical CT system. Methods: Three physical phantoms, including a water cylinder and two pediatric head phantoms, were scanned in axial scanning mode using a 64-slice CT scanner (Discovery CT750 HD, GE Healthcare, Waukesha, WI) at seven different mAs levels (5, 12.5, 25, 50, 100, 200, 300). At each mAs level, each phantom was repeatedly scanned 50 times to generate an image ensemble for noise analysis. Both the FBP method with a standard kernel and the MBIR method (Veo{sup ®}, GE Healthcare, Waukesha, WI) were used for CT image reconstruction. Three-dimensional (3D) noise power spectrum (NPS), two-dimensional (2D) NPS, and zero-dimensional NPS (noise variance) were assessed both globally and locally. Noise magnitude, noise spatial correlation, noise spatial uniformity and their dose dependence were examined for the two reconstruction methods. Results: (1) At each dose level and at each frequency, the magnitude of the NPS of MBIR was smaller than that of FBP. (2) While the shape of the NPS of FBP was dose-independent, the shape of the NPS of MBIR was strongly dose-dependent; lower dose lead to a “redder” NPS with a lower mean frequency value. (3) The noise standard deviation (?) of MBIR and dose were found to be related through a power law of ????(dose){sup ??} with the component ? ? 0.25, which violated the classical ????(dose){sup ?0.5} power law in FBP. (4) With MBIR, noise reduction was most prominent for thin image slices. (5) MBIR lead to better noise spatial uniformity when compared with FBP. (6) A composite image generated from two MBIR images acquired at two different dose levels (D1 and D2) demonstrated lower noise than that of an image acquired at a dose level of D1+D2. Conclusions: The noise characteristics of the MBIR method are significantly different from those of the FBP method. The well known tradeoff relationship between CT image noise and radiation dose has been modified by MBIR to establish a more gradual dependence of noise on dose. Additionally, some other CT noise properties that had been well understood based on the linear system theory have also been altered by MBIR. Clinical CT scan protocols that had been optimized based on the classical CT noise properties need to be carefully re-evaluated for systems equipped with MBIR in order to maximize the method's potential clinical benefits in dose reduction and/or in CT image quality improvement.

  9. Compact Torus Accelerator Driven Inertial Confinement Fusion Power Plant HYLIFE-CT

    SciTech Connect (OSTI)

    Logan, B G; Moir, R W; Tabak, M; Bieri, R L; Hammer, J H; Hartman, C W; Hoffman, M A; Leber, R L; Petzoldt, R W; Tobin, M T

    2005-03-30

    A Compact Torus Accelerator (CTA) is used to accelerate a Compact Torus (CT) to 35 MJ kinetic energy which is focused to a 20 mm diameter where its kinetic energy is converted to a shaped x-ray pulse of 30 MJ. The capsule yield with a prescribed radiation profile is calculated to be (gain 60 times 30 MJ) 1.8 GJ. Schemes for achieving this profile are described. The CT is accelerated in a length of 30 m within an annulus of 150 mm ID and 300 mm OD where the maximum magnetic field is 28 T. A 2.5 m conical taper reduces the mean diameter of the CT from 225 mm to 20 mm. The conical section is made out of solid Li{sub 2}BeF{sub 4}. The target with its frozen conical guide section is accurately placed at the end of the accelerator about once per second. The reactor called HYLIFE uses liquid jets to attenuate blast effects including shrapnel from the shattered conical guide section and radiation so that the vessel is expected to last 30 years. The calculated cost of electricity is estimated (in constant 1988 dollars) to be about 4.8 cents/kW {center_dot} h compared to the future cost of nuclear and coal of 4.3 to 5.8 cents/kW {center_dot} h. The CT driver contributes 17% to the cost of electricity. Present CT's make 2 x 10{sup 8} W/cm{sup 2}; the goal of experiments in progress is 10{sup 11} W/cm{sup 2} with further modifications to allow 10{sup 12}W/cm{sup 2}, whereas the reactor requires 10{sup 15} W/cm{sup 2} in a shaped pulse.

  10. DISEASES OF AQUATIC ORGANISMS Dis Aquat Org

    E-Print Network [OSTI]

    Harvell, Catherine Drew

    from Florida; MFPS from PR) and the cultured microorganism are in the genus Aplanochytrium, although that the Labyrinthulomycetes associated with sea fans is likely an opportunistic pathogen. Further studies are needed to under- stand the pathogenesis of this microorganism in sea fans and its relationship with MFPS. KEY WORDS

  11. DISEASES OF AQUATIC ORGANISMS Dis Aquat Org

    E-Print Network [OSTI]

    James, Timothy

    declines and extinctions (Pounds et al. 2006, Skerratt et al. 2007). Knowledge of the epidemiology in the management of global amphibian trade (Skerratt et al. 2007). The pandemic form of Bd appears to have recently in their survey of se- quence variation at 17 nuclear loci from 59 Bd strains from the Americas, Africa, Australia

  12. DISEASES OF AQUATIC ORGANISMS Dis Aquat Org

    E-Print Network [OSTI]

    during the 1960s. Since then, QPX has caused high mortalities in hatchery-reared clams from Prince Edward

  13. DISEASES OF AQUATIC ORGANISMS Dis Aquat Org

    E-Print Network [OSTI]

    Aguirre, Windsor E.

    and ossifications of anterolateral ligaments of the vertebral column; and (4) spondyloarthritis, which includes Vertebral anomalies have been widely documented both from captive (e.g. Morton 1978, Alexander et al. 1989). Vertebral anomalies can result from a number of different pathogenic mechanisms, with different implications

  14. Careers & the disABLED Career Expo

    Broader source: Energy.gov [DOE]

    Location: Ronald Reagan Bldg, Washington, DCAttendees:  Terri Sosa (Science)POC:  Donna FriendWebsite: http://bit.ly/1tlHhNr

  15. DISEASES OF AQUATIC ORGANISMS Dis Aquat Org

    E-Print Network [OSTI]

    Harvell, Catherine Drew

    and disease in Mexico J. R. Ward1,*, K. L. Rypien1 , J. F. Bruno2 , C. D. Harvell1 , E. Jordán-Dahlgren3 , K Sciences, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3300, USA 3

  16. Reconstruction of a time-averaged midposition CT scan for radiotherapy planning of lung cancer patients using deformable registration

    SciTech Connect (OSTI)

    Wolthaus, J. W. H.; Sonke, J.-J.; Herk, M. van; Damen, E. M. F. [Department of Radiation Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands)

    2008-09-15

    Purpose: lower lobe lung tumors move with amplitudes of up to 2 cm due to respiration. To reduce respiration imaging artifacts in planning CT scans, 4D imaging techniques are used. Currently, we use a single (midventilation) frame of the 4D data set for clinical delineation of structures and radiotherapy planning. A single frame, however, often contains artifacts due to breathing irregularities, and is noisier than a conventional CT scan since the exposure per frame is lower. Moreover, the tumor may be displaced from the mean tumor position due to hysteresis. The aim of this work is to develop a framework for the acquisition of a good quality scan representing all scanned anatomy in the mean position by averaging transformed (deformed) CT frames, i.e., canceling out motion. A nonrigid registration method is necessary since motion varies over the lung. Methods and Materials: 4D and inspiration breath-hold (BH) CT scans were acquired for 13 patients. An iterative multiscale motion estimation technique was applied to the 4D CT scan, similar to optical flow but using image phase (gray-value transitions from bright to dark and vice versa) instead. From the (4D) deformation vector field (DVF) derived, the local mean position in the respiratory cycle was computed and the 4D DVF was modified to deform all structures of the original 4D CT scan to this mean position. A 3D midposition (MidP) CT scan was then obtained by (arithmetic or median) averaging of the deformed 4D CT scan. Image registration accuracy, tumor shape deviation with respect to the BH CT scan, and noise were determined to evaluate the image fidelity of the MidP CT scan and the performance of the technique. Results: Accuracy of the used deformable image registration method was comparable to established automated locally rigid registration and to manual landmark registration (average difference to both methods <0.5 mm for all directions) for the tumor region. From visual assessment, the registration was good for the clearly visible features (e.g., tumor and diaphragm). The shape of the tumor, with respect to that of the BH CT scan, was better represented by the MidP reconstructions than any of the 4D CT frames (including MidV; reduction of 'shape differences' was 66%). The MidP scans contained about one-third the noise of individual 4D CT scan frames. Conclusions: We implemented an accurate method to estimate the motion of structures in a 4D CT scan. Subsequently, a novel method to create a midposition CT scan (time-weighted average of the anatomy) for treatment planning with reduced noise and artifacts was introduced. Tumor shape and position in the MidP CT scan represents that of the BH CT scan better than MidV CT scan and, therefore, was found to be appropriate for treatment planning.

  17. Correlation between human observer performance and model observer performance in differential phase contrast CT

    SciTech Connect (OSTI)

    Li, Ke; Garrett, John; Chen, Guang-Hong

    2013-11-15

    Purpose: With the recently expanding interest and developments in x-ray differential phase contrast CT (DPC-CT), the evaluation of its task-specific detection performance and comparison with the corresponding absorption CT under a given radiation dose constraint become increasingly important. Mathematical model observers are often used to quantify the performance of imaging systems, but their correlations with actual human observers need to be confirmed for each new imaging method. This work is an investigation of the effects of stochastic DPC-CT noise on the correlation of detection performance between model and human observers with signal-known-exactly (SKE) detection tasks.Methods: The detectabilities of different objects (five disks with different diameters and two breast lesion masses) embedded in an experimental DPC-CT noise background were assessed using both model and human observers. The detectability of the disk and lesion signals was then measured using five types of model observers including the prewhitening ideal observer, the nonprewhitening (NPW) observer, the nonprewhitening observer with eye filter and internal noise (NPWEi), the prewhitening observer with eye filter and internal noise (PWEi), and the channelized Hotelling observer (CHO). The same objects were also evaluated by four human observers using the two-alternative forced choice method. The results from the model observer experiment were quantitatively compared to the human observer results to assess the correlation between the two techniques.Results: The contrast-to-detail (CD) curve generated by the human observers for the disk-detection experiments shows that the required contrast to detect a disk is inversely proportional to the square root of the disk size. Based on the CD curves, the ideal and NPW observers tend to systematically overestimate the performance of the human observers. The NPWEi and PWEi observers did not predict human performance well either, as the slopes of their CD curves tended to be steeper. The CHO generated the best quantitative agreement with human observers with its CD curve overlapping with that of human observer. Statistical equivalence between CHO and humans can be claimed within 11% of the human observer results, including both the disk and lesion detection experiments.Conclusions: The model observer method can be used to accurately represent human observer performance with the stochastic DPC-CT noise for SKE tasks with sizes ranging from 8 to 128 pixels. The incorporation of the anatomical noise remains to be studied.

  18. Adaptive nonlocal means filtering based on local noise level for CT denoising

    SciTech Connect (OSTI)

    Li, Zhoubo; Trzasko, Joshua D.; Lake, David S.; Blezek, Daniel J.; Manduca, Armando; Yu, Lifeng; Fletcher, Joel G.; McCollough, Cynthia H.

    2014-01-15

    Purpose: To develop and evaluate an image-domain noise reduction method based on a modified nonlocal means (NLM) algorithm that is adaptive to local noise level of CT images and to implement this method in a time frame consistent with clinical workflow. Methods: A computationally efficient technique for local noise estimation directly from CT images was developed. A forward projection, based on a 2D fan-beam approximation, was used to generate the projection data, with a noise model incorporating the effects of the bowtie filter and automatic exposure control. The noise propagation from projection data to images was analytically derived. The analytical noise map was validated using repeated scans of a phantom. A 3D NLM denoising algorithm was modified to adapt its denoising strength locally based on this noise map. The performance of this adaptive NLM filter was evaluated in phantom studies in terms of in-plane and cross-plane high-contrast spatial resolution, noise power spectrum (NPS), subjective low-contrast spatial resolution using the American College of Radiology (ACR) accreditation phantom, and objective low-contrast spatial resolution using a channelized Hotelling model observer (CHO). Graphical processing units (GPU) implementation of this noise map calculation and the adaptive NLM filtering were developed to meet demands of clinical workflow. Adaptive NLM was piloted on lower dose scans in clinical practice. Results: The local noise level estimation matches the noise distribution determined from multiple repetitive scans of a phantom, demonstrated by small variations in the ratio map between the analytical noise map and the one calculated from repeated scans. The phantom studies demonstrated that the adaptive NLM filter can reduce noise substantially without degrading the high-contrast spatial resolution, as illustrated by modulation transfer function and slice sensitivity profile results. The NPS results show that adaptive NLM denoising preserves the shape and peak frequency of the noise power spectrum better than commercial smoothing kernels, and indicate that the spatial resolution at low contrast levels is not significantly degraded. Both the subjective evaluation using the ACR phantom and the objective evaluation on a low-contrast detection task using a CHO model observer demonstrate an improvement on low-contrast performance. The GPU implementation can process and transfer 300 slice images within 5 min. On patient data, the adaptive NLM algorithm provides more effective denoising of CT data throughout a volume than standard NLM, and may allow significant lowering of radiation dose. After a two week pilot study of lower dose CT urography and CT enterography exams, both GI and GU radiology groups elected to proceed with permanent implementation of adaptive NLM in their GI and GU CT practices. Conclusions: This work describes and validates a computationally efficient technique for noise map estimation directly from CT images, and an adaptive NLM filtering based on this noise map, on phantom and patient data. Both the noise map calculation and the adaptive NLM filtering can be performed in times that allow integration with clinical workflow. The adaptive NLM algorithm provides effective denoising of CT data throughout a volume, and may allow significant lowering of radiation dose.

  19. Cholecystokinin-Assisted Hydrodissection of the Gallbladder Fossa during FDG PET/CT-guided Liver Ablation

    SciTech Connect (OSTI)

    Tewari, Sanjit O.; Petre, Elena N.; Osborne, Joseph; Sofocleous, Constantinos T.

    2013-12-15

    A 68-year-old female with colorectal cancer developed a metachronous isolated fluorodeoxyglucose-avid (FDG-avid) segment 5/6 gallbladder fossa hepatic lesion and was referred for percutaneous ablation. Pre-procedure computed tomography (CT) images demonstrated a distended gallbladder abutting the segment 5/6 hepatic metastasis. In order to perform ablation with clear margins and avoid direct puncture and aspiration of the gallbladder, cholecystokinin was administered intravenously to stimulate gallbladder contraction before hydrodissection. Subsequently, the lesion was ablated successfully with sufficient margins, of greater than 1.0 cm, using microwave with ultrasound and FDG PET/CT guidance. The patient tolerated the procedure very well and was discharged home the next day.

  20. Graystone Group Advertising, 2710 North Ave, Suite 200 Bridgeport, CT 06604 Phone: 8005440005 or 2035490060 Fax: 2035490061

    E-Print Network [OSTI]

    Stuart, Steven J.

    Graystone Group Advertising, 2710 North Ave, Suite 200 Bridgeport, CT 06604 Phone: 8005440005 or 2035490060 Fax: 2035490061 Email: ads@graystoneadv.com Placing Recruitment Advertising To assist University departments with all recruitment and advertising needs, Clemson is now partnered

  1. Dose reconstruction for real-time patient-specific dose estimation in CT

    SciTech Connect (OSTI)

    De Man, Bruno Yin, Zhye; Wu, Mingye; FitzGerald, Paul; Kalra, Mannudeep

    2015-05-15

    Purpose: Many recent computed tomography (CT) dose reduction approaches belong to one of three categories: statistical reconstruction algorithms, efficient x-ray detectors, and optimized CT acquisition schemes with precise control over the x-ray distribution. The latter category could greatly benefit from fast and accurate methods for dose estimation, which would enable real-time patient-specific protocol optimization. Methods: The authors present a new method for volumetrically reconstructing absorbed dose on a per-voxel basis, directly from the actual CT images. The authors’ specific implementation combines a distance-driven pencil-beam approach to model the first-order x-ray interactions with a set of Gaussian convolution kernels to model the higher-order x-ray interactions. The authors performed a number of 3D simulation experiments comparing the proposed method to a Monte Carlo based ground truth. Results: The authors’ results indicate that the proposed approach offers a good trade-off between accuracy and computational efficiency. The images show a good qualitative correspondence to Monte Carlo estimates. Preliminary quantitative results show errors below 10%, except in bone regions, where the authors see a bigger model mismatch. The computational complexity is similar to that of a low-resolution filtered-backprojection algorithm. Conclusions: The authors present a method for analytic dose reconstruction in CT, similar to the techniques used in radiation therapy planning with megavoltage energies. Future work will include refinements of the proposed method to improve the accuracy as well as a more extensive validation study. The proposed method is not intended to replace methods that track individual x-ray photons, but the authors expect that it may prove useful in applications where real-time patient-specific dose estimation is required.

  2. SU-E-P-03: Implementing a Low Dose Lung Screening CT Program Meeting Regulatory Requirements

    SciTech Connect (OSTI)

    LaFrance, M; Marsh, S; O'Donnell, G

    2014-06-01

    Purpose: To provide information pertaining to IROC Houston QA Center's (RPC) credentialing process for institutions participating in NCI-sponsored clinical trials. Purpose: Provide guidance to the Radiology Departments with the intent of implementing a Low Dose CT Screening Program using different CT Scanners with multiple techniques within the framework of the required state regulations. Method: State Requirements for the purpose of implementing a Low Dose CT Lung Protocol required working with the Radiology and Pulmonary Department in setting up a Low Dose Screening Protocol designed to reduce the radiation burden to the patients enrolled. Radiation dose measurements (CTDIvol) for various CT manufacturers (Siemens16, Siemens 64, Philips 64, and Neusoft128) for three different weight based protocols. All scans were reviewed by the Radiologist. Prior to starting a low dose lung screening protocol, information had to be submitted to the state for approval. Performing a Healing Arts protocol requires extensive information. This not only includes name and address of the applicant but a detailed description of the disease, the x-ray examination and the population to be examined. The unit had to be tested by a qualified expert using the technique charts. The credentials of all the operators, the supervisors and the Radiologists had to be submitted to the state. Results: All the appropriate documentation was sent to the state for review. The measured results between the Low Dose Protocol versus the default Adult Chest Protocol showed that there was a dose reduction of 65% for small (100-150 lb.) patient, 75% for the Medium patient (151-250 lbs.), and a 55% reduction for the Large patient ( over 250 lbs.). Conclusion: Measured results indicated that the Low Dose Protocol indeed lowered the screening patient's radiation dose and the institution was able to submit the protocol to the State's regulators.

  3. SU-E-I-43: Pediatric CT Dose and Image Quality Optimization

    SciTech Connect (OSTI)

    Stevens, G; Singh, R

    2014-06-01

    Purpose: To design an approach to optimize radiation dose and image quality for pediatric CT imaging, and to evaluate expected performance. Methods: A methodology was designed to quantify relative image quality as a function of CT image acquisition parameters. Image contrast and image noise were used to indicate expected conspicuity of objects, and a wide-cone system was used to minimize scan time for motion avoidance. A decision framework was designed to select acquisition parameters as a weighted combination of image quality and dose. Phantom tests were used to acquire images at multiple techniques to demonstrate expected contrast, noise and dose. Anthropomorphic phantoms with contrast inserts were imaged on a 160mm CT system with tube voltage capabilities as low as 70kVp. Previously acquired clinical images were used in conjunction with simulation tools to emulate images at different tube voltages and currents to assess human observer preferences. Results: Examination of image contrast, noise, dose and tube/generator capabilities indicates a clinical task and object-size dependent optimization. Phantom experiments confirm that system modeling can be used to achieve the desired image quality and noise performance. Observer studies indicate that clinical utilization of this optimization requires a modified approach to achieve the desired performance. Conclusion: This work indicates the potential to optimize radiation dose and image quality for pediatric CT imaging. In addition, the methodology can be used in an automated parameter selection feature that can suggest techniques given a limited number of user inputs. G Stevens and R Singh are employees of GE Healthcare.

  4. Transhepatic CT-Guided Radiofrequency Ablation of Adrenal Metastases from Hepatocellular Carcinoma

    SciTech Connect (OSTI)

    Kuehl, Hilmar, E-mail: hilmar.kuehl@uni-due.de; Stattaus, Joerg; Forsting, Michael; Antoch, Gerald [University Hospital Essen, University at Duisburg-Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology (Germany)

    2008-11-15

    The prognosis of patients with adrenal metastases from hepatocellular carcinoma (HCC) has been poor, and aggressive treatment of these tumors is mandatory to improve patients' survival. Since adrenalectomy may be difficult to perform after previous surgery of the right liver lobe, other approaches are required to treat the adrenal mass. This report aims at demonstrating the feasibility of CT-guided transhepatic radiofrequency ablation of right adrenal HCC metastases pretreated with chemoembolization in patients unable to undergo surgical resection.

  5. Cone Beam CT Imaging Analysis of Interfractional Variations in Bladder Volume and Position During Radiotherapy for Bladder Cancer

    SciTech Connect (OSTI)

    Yee, Don, E-mail: dony@ualberta.c [Department of Radiation Oncology, Cross Cancer Institute, Edmonton, Alberta (Canada); Parliament, Matthew [Department of Radiation Oncology, Cross Cancer Institute, Edmonton, Alberta (Canada); Rathee, Satyapal [Department of Medical Physics, Cross Cancer Institute, Edmonton, Alberta (Canada); Ghosh, Sunita [Department of Experimental Oncology, Cross Cancer Institute, Edmonton, Alberta (Canada); Ko, Lawrence [Department of Radiation Oncology, Cross Cancer Institute, Edmonton, Alberta (Canada); Murray, Brad [Department of Medical Physics, Cross Cancer Institute, Edmonton, Alberta (Canada)

    2010-03-15

    Purpose: To quantify daily bladder size and position variations during bladder cancer radiotherapy. Methods and Materials: Ten bladder cancer patients underwent daily cone beam CT (CBCT) imaging of the bladder during radiotherapy. Bladder and planning target volumes (bladder/PTV) from CBCT and planning CT scans were compared with respect to bladder center-of-mass shifts in the x (lateral), y (anterior-posterior), and z (superior-inferior) coordinates, bladder/PTV size, bladder/PTV margin positions, overlapping areas, and mutually exclusive regions. Results: A total of 262 CBCT images were obtained from 10 bladder cancer patients. Bladder center of mass shifted most in the y coordinate (mean, -0.32 cm). The anterior bladder wall shifted the most (mean, -0.58 cm). Mean ratios of CBCT-derived bladder and PTV volumes to planning CT-derived counterparts were 0.83 and 0.88. The mean CBCT-derived bladder volume (+- standard deviation [SD]) outside the planning CT counterpart was 29.24 cm{sup 3} (SD, 29.71 cm{sup 3}). The mean planning CT-derived bladder volume outside the CBCT counterpart was 47.74 cm{sup 3} (SD, 21.64 cm{sup 3}). The mean CBCT PTV outside the planning CT-derived PTV was 47.35 cm{sup 3} (SD, 36.51 cm{sup 3}). The mean planning CT-derived PTV outside the CBCT-derived PTV was 93.16 cm{sup 3} (SD, 50.21). The mean CBCT-derived bladder volume outside the planning PTV was 2.41 cm{sup 3} (SD, 3.97 cm{sup 3}). CBCT bladder/ PTV volumes significantly differed from planning CT counterparts (p = 0.047). Conclusions: Significant variations in bladder and PTV volume and position occurred in patients in this trial.

  6. Tri-Generation Success World's First Tri-Gen

    E-Print Network [OSTI]

    station uses anaerobically digested biogas from the municipal wastewater treatment plant as the fuel SAE protocols for rapid 3-minute complete tank refueling. Gas or Biogas H2 is produced at anode Gas the versatility of fuel cells to utilize multiple feedstocks, such as biogas and natural gas, to produce power

  7. CT-Guided Radiofrequency Ablation in Patients with Hepatic Metastases from Breast Cancer

    SciTech Connect (OSTI)

    Jakobs, Tobias F., E-mail: tobias.jakobs@med.uni-muenchen.de; Hoffmann, Ralf-Thorsten; Schrader, Angelika [Ludwig-Maximilians-University of Munich, Department of Radiology (Germany); Stemmler, Hans Joachim [Ludwig-Maximilians-University of Munich, Department of Internal Medicine III (Germany); Trumm, Christoph [Ludwig-Maximilians-University of Munich, Department of Radiology (Germany); Lubienski, Andreas [University of Schleswig-Holstein, Department of Radiology (Germany); Murthy, Ravi [The University of Texas M. D. Anderson Cancer Center, Division of Diagnostic Imaging (United States); Helmberger, Thomas K. [Klinikum Bogenhausen, Department of Radiology (Germany); Reiser, Maximilian F. [Ludwig-Maximilians-University of Munich, Department of Radiology (Germany)

    2009-01-15

    The purpose of this study was to evaluate technical success, technique effectiveness, and survival following radiofrequency ablation for breast cancer liver metastases and to determine prognostic factors. Forty-three patients with 111 breast cancer liver metastases underwent CT-guided percutaneous radiofrequency (RF) ablation. Technical success and technique effectiveness was evaluated by performing serial CT scans. We assessed the prognostic value of hormone receptor status, overexpression of human epidermal growth factor receptor 2 (HER2), and presence of extrahepatic tumor spread. Survival rates were calculated using the Kaplan-Meier method. Technical success was achieved in 107 metastases (96%). Primary technique effectiveness was 96%. During follow-up local tumor progression was observed in 15 metastases, representing a secondary technique effectiveness of 86.5%. The overall time to progression to the liver was 10.5 months. The estimated overall median survival was 58.6 months. There was no significant difference in terms of survival probability with respect to hormone receptor status, HER2 overexpression, and presence of isolated bone metastases. Survival was significantly lower among patients with extrahepatic disease, with the exception of skeletal metastases. We conclude that CT-guided RF ablation of liver metastases from breast cancer can be performed with a high degree of technical success and technique effectiveness, providing promising survival rates in patients with no visceral extrahepatic disease. Solitary bone metastases did not negatively affect survival probability after RF ablation.

  8. Quality assurance for image-guided radiation therapy utilizing CT-based technologies: A report of the AAPM TG-179

    SciTech Connect (OSTI)

    Bissonnette, Jean-Pierre; Balter, Peter A.; Dong Lei; Langen, Katja M.; Lovelock, D. Michael; Miften, Moyed; Moseley, Douglas J.; Pouliot, Jean; Sonke, Jan-Jakob; Yoo, Sua

    2012-04-15

    Purpose: Commercial CT-based image-guided radiotherapy (IGRT) systems allow widespread management of geometric variations in patient setup and internal organ motion. This document provides consensus recommendations for quality assurance protocols that ensure patient safety and patient treatment fidelity for such systems. Methods: The AAPM TG-179 reviews clinical implementation and quality assurance aspects for commercially available CT-based IGRT, each with their unique capabilities and underlying physics. The systems described are kilovolt and megavolt cone-beam CT, fan-beam MVCT, and CT-on-rails. A summary of the literature describing current clinical usage is also provided. Results: This report proposes a generic quality assurance program for CT-based IGRT systems in an effort to provide a vendor-independent program for clinical users. Published data from long-term, repeated quality control tests form the basis of the proposed test frequencies and tolerances.Conclusion: A program for quality control of CT-based image-guidance systems has been produced, with focus on geometry, image quality, image dose, system operation, and safety. Agreement and clarification with respect to reports from the AAPM TG-101, TG-104, TG-142, and TG-148 has been addressed.

  9. MO-PIS-Exhibit Hall-01: Imaging: CT Dose Optimization Technologies I

    SciTech Connect (OSTI)

    Denison, K; Smith, S

    2014-06-15

    Partners in Solutions is an exciting new program in which AAPM partners with our vendors to present practical “hands-on” information about the equipment and software systems that we use in our clinics. The imaging topic this year is CT scanner dose optimization capabilities. Note that the sessions are being held in a special purpose room built on the Exhibit Hall Floor, to encourage further interaction with the vendors. Dose Optimization Capabilities of GE Computed Tomography Scanners Presentation Time: 11:15 – 11:45 AM GE Healthcare is dedicated to the delivery of high quality clinical images through the development of technologies, which optimize the application of ionizing radiation. In computed tomography, dose management solutions fall into four categories: employs projection data and statistical modeling to decrease noise in the reconstructed image - creating an opportunity for mA reduction in the acquisition of diagnostic images. Veo represents true Model Based Iterative Reconstruction (MBiR). Using high-level algorithms in tandem with advanced computing power, Veo enables lower pixel noise standard deviation and improved spatial resolution within a single image. Advanced Adaptive Image Filters allow for maintenance of spatial resolution while reducing image noise. Examples of adaptive image space filters include Neuro 3-D filters and Cardiac Noise Reduction Filters. AutomA adjusts mA along the z-axis and is the CT equivalent of auto exposure control in conventional x-ray systems. Dynamic Z-axis Tracking offers an additional opportunity for dose reduction in helical acquisitions while SmartTrack Z-axis Tracking serves to ensure beam, collimator and detector alignment during tube rotation. SmartmA provides angular mA modulation. ECG Helical Modulation reduces mA during the systolic phase of the heart cycle. SmartBeam optimization uses bowtie beam-shaping hardware and software to filter off-axis x-rays - minimizing dose and reducing x-ray scatter. The DICOM Radiation Dose Structured Report (RDSR) generates a dose report at the conclusion of every examination. Dose Check preemptively notifies CT operators when scan parameters exceed user-defined dose thresholds. DoseWatch is an information technology application providing vendor-agnostic dose tracking and analysis for CT (and all other diagnostic x-ray modalities) SnapShot Pulse improves coronary CTA dose management. VolumeShuttle uses two acquisitions to increase coverage, decrease dose, and conserve on contrast administration. Color-Coding for Kids applies the Broselow-Luten Pediatric System to facilitate pediatric emergency care and reduce medical errors. FeatherLight achieves dose optimization through pediatric procedure-based protocols. Adventure Series scanners provide a child-friendly imaging environment promoting patient cooperation with resultant reduction in retakes and patient motion. Philips CT Dose Optimization Tools and Advanced Reconstruction Presentation Time: 11:45 ‘ 12:15 PM The first part of the talk will cover “Dose Reduction and Dose Optimization Technologies” present in Philips CT Scanners. The main Technologies to be presented include: DoseRight and tube current modulation (DoseRight, Z-DOM, 3D-DOM, DoseRight Cardiac) Special acquisition modes Beam filtration and beam shapers Eclipse collimator and ClearRay collimator NanoPanel detector DoseRight will cover automatic tube current selection that automatically adjusts the dose for the individual patient. The presentation will explore the modulation techniques currently employed in Philips CT scanners and will include the algorithmic concepts as well as illustrative examples. Modulation and current selection technologies to be covered include the Automatic Current Selection component of DoseRight, ZDOM longitudinal dose modulation, 3D-DOM (combination of longitudinal and rotational dose modulation), Cardiac Dose right (an ECG based dose modulation scheme), and the DoseRight Index (DRI) IQ index. The special acquisition modes covers acquisition techniques such as prospective gating that

  10. Development of a dynamic quality assurance testing protocol for multisite clinical trial DCE-CT accreditation

    SciTech Connect (OSTI)

    Driscoll, B.; Keller, H.; Jaffray, D.; Coolens, C.; Department of Radiation Oncology, University of Toronto, 150 College Street, Toronto, Ontario M5S 3E2; Techna Institute, University Health Network, 124-100 College Street, Toronto, Ontario M5G 1L5

    2013-08-15

    Purpose: Credentialing can have an impact on whether or not a clinical trial produces useful quality data that is comparable between various institutions and scanners. With the recent increase of dynamic contrast enhanced-computed tomography (DCE-CT) usage as a companion biomarker in clinical trials, effective quality assurance, and control methods are required to ensure there is minimal deviation in the results between different scanners and protocols at various institutions. This paper attempts to address this problem by utilizing a dynamic flow imaging phantom to develop and evaluate a DCE-CT quality assurance (QA) protocol.Methods: A previously designed flow phantom, capable of producing predictable and reproducible time concentration curves from contrast injection was fully validated and then utilized to design a DCE-CT QA protocol. The QA protocol involved a set of quantitative metrics including injected and total mass error, as well as goodness of fit comparison to the known truth concentration curves. An additional region of interest (ROI) sensitivity analysis was also developed to provide additional details on intrascanner variability and determine appropriate ROI sizes for quantitative analysis. Both the QA protocol and ROI sensitivity analysis were utilized to test variations in DCE-CT results using different imaging parameters (tube voltage and current) as well as alternate reconstruction methods and imaging techniques. The developed QA protocol and ROI sensitivity analysis was then applied at three institutions that were part of clinical trial involving DCE-CT and results were compared.Results: The inherent specificity of robustness of the phantom was determined through calculation of the total intraday variability and determined to be less than 2.2 ± 1.1% (total calculated output contrast mass error) with a goodness of fit (R{sup 2}) of greater than 0.99 ± 0.0035 (n= 10). The DCE-CT QA protocol was capable of detecting significant deviations from the expected phantom result when scanning at low mAs and low kVp in terms of quantitative metrics (Injected Mass Error 15.4%), goodness of fit (R{sup 2}) of 0.91, and ROI sensitivity (increase in minimum input function ROI radius by 146 ± 86%). These tests also confirmed that the ASIR reconstruction process was beneficial in reducing noise without substantially increasing partial volume effects and that vendor specific modes (e.g., axial shuttle) did not significantly affect the phantom results. The phantom and QA protocol were finally able to quickly (<90 min) and successfully validate the DCE-CT imaging protocol utilized at the three separate institutions of a multicenter clinical trial; thereby enhancing the confidence in the patient data collected.Conclusions: A DCE QA protocol was developed that, in combination with a dynamic multimodality flow phantom, allows the intrascanner variability to be separated from other sources of variability such as the impact of injection protocol and ROI selection. This provides a valuable resource that can be utilized at various clinical trial institutions to test conformance with imaging protocols and accuracy requirements as well as ensure that the scanners are performing as expected for dynamic scans.

  11. Comparison of an alternative and existing binning methods to reduce the acquisition duration of 4D PET/CT

    SciTech Connect (OSTI)

    Didierlaurent, David, E-mail: dadidierlaurent@gmail.com; Ribes, Sophie; Caselles, Olivier [SIMAD, LU 50, Université Toulouse III Paul Sabatier, Toulouse 31062 (France); Jaudet, Cyril; Dierickx, Lawrence O.; Zerdoud, Slimane; Brillouet, Severine; Weits, Kathleen [Institut Claudius Regaud, 20-24 Rue du Pont Saint-Pierre, Toulouse 31052 (France); Batatia, Hadj [IRIT-INPT, Université Toulouse III Paul Sabatier, Toulouse 31071 (France); Courbon, Frédéric [GCS CHU-CLCC, Université Toulouse III Paul Sabatier, Toulouse 31052 (France)

    2014-11-01

    Purpose: Respiratory motion is a source of artifacts that reduce image quality in PET. Four dimensional (4D) PET/CT is one approach to overcome this problem. Existing techniques to limiting the effects of respiratory motions are based on prospective phase binning which requires a long acquisition duration (15–25 min). This time is uncomfortable for the patients and limits the clinical exploitation of 4D PET/CT. In this work, the authors evaluated an existing method and an alternative retrospective binning method to reduce the acquisition duration of 4D PET/CT. Methods: The authors studied an existing mixed-amplitude binning (MAB) method and an alternative binning method by mixed-phases (MPhB). Before implementing MPhB, they analyzed the regularity of the breathing patterns in patients. They studied the breathing signal drift and missing CT slices that could be challenging for implementing MAB. They compared the performance of MAB and MPhB with current binning methods to measure the maximum uptake, internal volume, and maximal range of tumor motion. Results: MPhB can be implemented depending on an optimal phase (in average, the exhalation peak phase ?4.1% of the entire breathing cycle duration). Signal drift of patients was in average 35% relative to the breathing amplitude. Even after correcting this drift, MAB was feasible in 4D CT for only 64% of patients. No significant differences appeared between the different binning methods to measure the maximum uptake, internal volume, and maximal range of tumor motion. The authors also determined the inaccuracies of MAB and MPhB to measure the maximum amplitude of tumor motion with three bins (less than 3 mm for movement inferior to 12 mm, up to 6.4 mm for a 21 mm movement). Conclusions: The authors proposed an alternative binning method by mixed-phase binning that halves the acquisition duration of 4D PET/CT. Mixed-amplitude binning was challenging because of signal drift and missing CT slices. They showed that more than three bins were necessary for a more accurate measurement of the maximum amplitude of the tumor motion. However, the current 4D-CT technology limits the increase of the number of bins in 4D PET/CT because of missing CT slices. One can reconstruct 4D PET images with more bins but without attenuation/scatter correction.

  12. Tri-State Synfuels Project Review: Volume 8. Commercial status of licensed process units. [Proposed Henderson, Kentucky coal to gasoline plant; licensed commercial processes

    SciTech Connect (OSTI)

    Not Available

    1982-06-01

    This document demonstrates the commercial status of the process units to be used in the Tri-State Synfuels Project at Henderson, Kentucky. The basic design philosophy as established in October, 1979, was to use the commercial SASOL II/III plants as a basis. This was changed in January 1982 to a plant configuration to produce gasoline via a methanol and methanol to gasoline process. To accomplish this change the Synthol, Oil workup and Chemical Workup Units were eliminated and replaced by Methanol Synthesis and Methanol to Gasoline Units. Certain other changes to optimize the Lurgi liquids processing eliminated the Tar Distillation and Naphtha Hydrotreater Units which were replaced by the Partial Oxidation Unit. The coals to be gasified are moderately caking which necessitates the installation of stirring mechanism in the Lurgi Dry Bottom gasifier. This work is in the demonstration phase. Process licenses either have been obtained or must be obtained for a number of processes to be used in the plant. The commercial nature of these processes is discussed in detail in the tabbed sections of this document. In many cases there is a list of commercial installations at which the licensed equipment is used.

  13. Chemicals, fuels and electricity from coal. A proposed tri-generation concept for utilization of CO{sub 2} from power plants

    SciTech Connect (OSTI)

    Song, C.

    1999-07-01

    A tri-generation concept is proposed for the 21st century for making liquid fuels and chemicals along with electricity using CO{sub 2} from flue gases of coal-based electric power plants. The CO{sub 2} from flue gas in the power plant can be converted with CH{sub 4} (natural gas) to form synthesis gas (CO and H{sub 2} mixture) using the waste heat in the power plant. The H{sub 2}O and O{sub 2} in the flue gas will be used as co-reactants and need not be separated from the flue gas. The hot synthesis gas can be used as feedstock for fuel cells for electricity generation (such as MCFC and SOFC). The hot synthesis gas can also be used for gas turbines to generate electricity. The synthesis gas at moderate temperature can be converted into chemicals and fuels, e.g., methanol and mixed alcohols for chemical and fuel uses, dimethylether (DME) and mixed ethers for diesel fuel, dimethyl carbonate and acetic acid for chemicals. The fuels thus produced may be used either for conventional IC engines or in fuel cell-driven vehicles. This concept could also be applied, in principle, for natural gas-based power plants and IGCC power plants.

  14. Radiation-induced refraction artifacts in the optical CT readout of polymer gel dosimeters

    SciTech Connect (OSTI)

    Campbell, Warren G.; Jirasek, Andrew; Wells, Derek M.

    2014-11-01

    Purpose: The objective of this work is to demonstrate imaging artifacts that can occur during the optical computed tomography (CT) scanning of polymer gel dosimeters due to radiation-induced refractive index (RI) changes in polyacrylamide gels. Methods: A 1 L cylindrical polyacrylamide gel dosimeter was irradiated with 3 × 3 cm{sup 2} square beams of 6 MV photons. A prototype fan-beam optical CT scanner was used to image the dosimeter. Investigative optical CT scans were performed to examine two types of rayline bending: (i) bending within the plane of the fan-beam and (ii) bending out the plane of the fan-beam. To address structured errors, an iterative Savitzky–Golay (ISG) filtering routine was designed to filter 2D projections in sinogram space. For comparison, 2D projections were alternatively filtered using an adaptive-mean (AM) filter. Results: In-plane rayline bending was most notably observed in optical CT projections where rays of the fan-beam confronted a sustained dose gradient that was perpendicular to their trajectory but within the fan-beam plane. These errors caused distinct streaking artifacts in image reconstructions due to the refraction of higher intensity rays toward more opaque regions of the dosimeter. Out-of-plane rayline bending was observed in slices of the dosimeter that featured dose gradients perpendicular to the plane of the fan-beam. These errors caused widespread, severe overestimations of dose in image reconstructions due to the higher-than-actual opacity that is perceived by the scanner when light is bent off of the detector array. The ISG filtering routine outperformed AM filtering for both in-plane and out-of-plane rayline errors caused by radiation-induced RI changes. For in-plane rayline errors, streaks in an irradiated region (>7 Gy) were as high as 49% for unfiltered data, 14% for AM, and 6% for ISG. For out-of-plane rayline errors, overestimations of dose in a low-dose region (?50 cGy) were as high as 13 Gy for unfiltered data, 10 Gy for AM, and 3.1 Gy for ISG. The ISG routine also addressed unrelated artifacts that previously needed to be manually removed in sinogram space. However, the ISG routine blurred reconstructions, causing losses in spatial resolution of ?5 mm in the plane of the fan-beam and ?8 mm perpendicular to the fan-beam. Conclusions: This paper reveals a new category of imaging artifacts that can affect the optical CT readout of polyacrylamide gel dosimeters. Investigative scans show that radiation-induced RI changes can cause significant rayline errors when rays confront a prolonged dose gradient that runs perpendicular to their trajectory. In fan-beam optical CT, these errors manifested in two ways: (1) distinct streaking artifacts caused by in-plane rayline bending and (2) severe overestimations of opacity caused by rays bending out of the fan-beam plane and missing the detector array. Although the ISG filtering routine mitigated these errors better than an adaptive-mean filtering routine, it caused unacceptable losses in spatial resolution.

  15. On two-parameter models of photon cross sections: Application to dual-energy CT imaging

    SciTech Connect (OSTI)

    Williamson, Jeffrey F.; Li Sicong; Devic, Slobodan; Whiting, Bruce R.; Lerma, Fritz A.

    2006-11-15

    The goal of this study is to evaluate the theoretically achievable accuracy in estimating photon cross sections at low energies (20-1000 keV) from idealized dual-energy x-ray computed tomography (CT) images. Cross-section estimation from dual-energy measurements requires a model that can accurately represent photon cross sections of any biological material as a function of energy by specifying only two characteristic parameters of the underlying material, e.g., effective atomic number and density. This paper evaluates the accuracy of two commonly used two-parameter cross-section models for postprocessing idealized measurements derived from dual-energy CT images. The parametric fit model (PFM) accounts for electron-binding effects and photoelectric absorption by power functions in atomic number and energy and scattering by the Klein-Nishina cross section. The basis-vector model (BVM) assumes that attenuation coefficients of any biological substance can be approximated by a linear combination of mass attenuation coefficients of two dissimilar basis substances. Both PFM and BVM were fit to a modern cross-section library for a range of elements and mixtures representative of naturally occurring biological materials (Z=2-20). The PFM model, in conjunction with the effective atomic number approximation, yields estimated the total linear cross-section estimates with mean absolute and maximum error ranges of 0.6%-2.2% and 1%-6%, respectively. The corresponding error ranges for BVM estimates were 0.02%-0.15% and 0.1%-0.5%. However, for photoelectric absorption frequency, the PFM absolute mean and maximum errors were 10.8%-22.4% and 29%-50%, compared with corresponding BVM errors of 0.4%-11.3% and 0.5%-17.0%, respectively. Both models were found to exhibit similar sensitivities to image-intensity measurement uncertainties. Of the two models, BVM is the most promising approach for realizing dual-energy CT cross-section measurement.

  16. Stationary table CT dosimetry and anomalous scanner-reported values of CTDI{sub vol}

    SciTech Connect (OSTI)

    Dixon, Robert L., E-mail: rdixon@wfubmc.edu [Department of Radiology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157 (United States); Boone, John M. [Departments of Radiology and Biomedical Engineering, University of California Davis, Sacramento, California 95817 (United States)] [Departments of Radiology and Biomedical Engineering, University of California Davis, Sacramento, California 95817 (United States)

    2014-01-15

    Purpose: Anomalous, scanner-reported values of CTDI{sub vol} for stationary phantom/table protocols (having elevated values of CTDI{sub vol} over 300% higher than the actual dose to the phantom) have been observed; which are well-beyond the typical accuracy expected of CTDI{sub vol} as a phantom dose. Recognition of these outliers as “bad data” is important to users of CT dose index tracking systems (e.g., ACR DIR), and a method for recognition and correction is provided. Methods: Rigorous methods and equations are presented which describe the dose distributions for stationary-table CT. A comparison with formulae for scanner-reported values of CTDI{sub vol} clearly identifies the source of these anomalies. Results: For the stationary table, use of the CTDI{sub 100} formula (applicable to a moving phantom only) overestimates the dose due to extra scatter and also includes an overbeaming correction, both of which are nonexistent when the phantom (or patient) is held stationary. The reported DLP remains robust for the stationary phantom. Conclusions: The CTDI-paradigm does not apply in the case of a stationary phantom and simpler nonintegral equations suffice. A method of correction of the currently reported CTDI{sub vol} using the approach-to-equilibrium formula H(a) and an overbeaming correction factor serves to scale the reported CTDI{sub vol} values to more accurate levels for stationary-table CT, as well as serving as an indicator in the detection of “bad data.”.

  17. SU-E-T-99: Design and Development of Isocenter Parameter System for CT Simulation Laser Based On DICOM RT

    SciTech Connect (OSTI)

    Luo, G

    2014-06-01

    Purpose: In order to receive DICOM files from treatment planning system and generate patient isocenter positioning parameter file for CT laser system automatically, this paper presents a method for communication with treatment planning system and calculation of isocenter parameter for each radiation field. Methods: Coordinate transformation and laser positioning file formats were analyzed, isocenter parameter was calculated via data from DICOM CT Data and DICOM RTPLAN file. An in-house software-DicomGenie was developed based on the object-oriented program platform-Qt with DCMTK SDK (Germany OFFIS company DICOM SDK) . DicomGenie was tested for accuracy using Philips CT simulation plan system (Tumor LOC, Philips) and A2J CT positioning laser system (Thorigny Sur Marne, France). Results: DicomGenie successfully established DICOM communication between treatment planning system, DICOM files were received by DicomGenie and patient laser isocenter information was generated accurately. Patient laser parameter data files can be used for for CT laser system directly. Conclusion: In-house software DicomGenie received and extracted DICOM data, isocenter laser positioning data files were created by DicomGenie and can be use for A2J laser positioning system.

  18. Application of Fourier transform infrared spectroscopy to silica diagenesis: The opal-A to opal-CT transformation

    SciTech Connect (OSTI)

    Rice, S.B.; Freund, H.; Huang, W.L.; Clouse, J.A.; Isaacs, C.M.

    1995-10-02

    An important goal in silica diagenesis research is to understand the kinetics of opal transformation from noncrystalline opal-A to the disordered silica polymorph opal-CT. Because the conventional technique for monitoring the transformation, powder X-ray diffraction (XRD), is applicable only to phases with long-range order, the authors used Fourier transform infrared spectroscopy (FTIR) to monitor the transformation. They applied this technique, combined with XRD and TEM, to experimental run products and natural opals from the Monterey Formation and from siliceous deposits in the western Pacific Ocean. Using a ratio of two infrared absorption intensities ({omega} = I{sub 472 cm{sup {minus}1}}/I{sub 500 cm{sup {minus}1}}), the relative proportions of opal-A and opal-CT can be determined. The progress of the transformation is marked by changes in slope of {omega} vs. depth or time when a sufficient stratigraphic profile is available. There are three stages in the opal-A to opal-CT reaction: (1) opal-A dissolution; (2) opal-CT precipitation, whose end point is marked by completion of opal-A dissolution; and (3) opal-CT ordering, during which tridymite stacking is eliminated in favor of crystobalite stacking.

  19. Independent measurement of femoral cortical thickness and cortical bone density using clinical CT

    E-Print Network [OSTI]

    Treece, G. M.; Gee, A. H.

    2014-12-05

    for CBM v2 in eq. (4) by using eq. (1) to simulate the CT data variation c(x) through ideal cortices, i.e. with perfectly constant density and no pores, surrounded by material which is also at a constant (but lower) density. These cortices were blurred... are shown in Fig. 4. 3.2. Comparing HRpQCT and QCT data Moving on from simulations, we examined data from a study ethically approved by the Medical University of 5 0 1 2 3 4 5 0 500 1000 1500 thickness (mm) de ns ity (H U) yb y m raw data model fit...

  20. Implementation and commissioning of an integrated micro-CT/RT system with computerized independent jaw collimation

    SciTech Connect (OSTI)

    Jensen, Michael D.; Hrinivich, W. Thomas; Jung, Jongho A.; Holdsworth, David W.; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7; Department of Surgery, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 ; Drangova, Maria; Chen, Jeff; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7; Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 ; Wong, Eugene; Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7; Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7; Department of Physics and Engineering, London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9

    2013-08-15

    Purpose: To design, construct, and commission a set of computer-controlled motorized jaws for a micro-CT/RT system to perform conformal image-guided small animal radiotherapy.Methods: The authors designed and evaluated a system of custom-built motorized orthogonal jaws, which allows the delivery of off-axis rectangular fields on a GE eXplore CT 120 preclinical imaging system. The jaws in the x direction are independently driven, while the y-direction jaws are symmetric. All motors have backup encoders, verifying jaw positions. Mechanical performance of the jaws was characterized. Square beam profiles ranging from 2 × 2 to 60 × 60 mm{sup 2} were measured using EBT2 film in the center of a 70 × 70 × 22 mm{sup 3} solid water block. Similarly, absolute depth dose was measured in a solid water and EBT2 film stack 50 × 50 × 50 mm{sup 3}. A calibrated Farmer ion chamber in a 70 × 70 × 20 mm{sup 3} solid water block was used to measure the output of three field sizes: 50 × 50, 40 × 40, and 30 × 30 mm{sup 2}. Elliptical target plans were delivered to films to assess overall system performance. Respiratory-gated treatment was implemented on the system and initially proved using a simple sinusoidal motion phantom. All films were scanned on a flatbed scanner (Epson 1000XL) and converted to dose using a fitted calibration curve. A Monte Carlo beam model of the micro-CT with the jaws has been created using BEAMnrc for comparison with the measurements. An example image-guided partial lung irradiation in a rat is demonstrated.Results: The averaged random error of positioning each jaw is less than 0.1 mm. Relative output factors measured with the ion chamber agree with Monte Carlo simulations within 2%. Beam profiles and absolute depth dose curves measured from the films agree with simulations within measurement uncertainty. Respiratory-gated treatments applied to a phantom moving with a peak-to-peak amplitude of 5 mm showed improved beam penumbra (80%–20%) from 3.9 to 0.8 mm.Conclusions: A set of computer-controlled motorized jaws for a micro-CT/RT system were constructed with position reliably better than a tenth of a millimeter. The hardware system is ready for image-guided conformal radiotherapy for small animals with capability of respiratory-gated delivery.

  1. Model-based PSF and MTF estimation and validation from skeletal clinical CT images

    SciTech Connect (OSTI)

    Pakdel, Amirreza; Mainprize, James G.; Robert, Normand; Fialkov, Jeffery; Whyne, Cari M.

    2014-01-15

    Purpose: A method was developed to correct for systematic errors in estimating the thickness of thin bones due to image blurring in CT images using bone interfaces to estimate the point-spread-function (PSF). This study validates the accuracy of the PSFs estimated using said method from various clinical CT images featuring cortical bones. Methods: Gaussian PSFs, characterized by a different extent in the z (scan) direction than in the x and y directions were obtained using our method from 11 clinical CT scans of a cadaveric craniofacial skeleton. These PSFs were estimated for multiple combinations of scanning parameters and reconstruction methods. The actual PSF for each scan setting was measured using the slanted-slit technique within the image slice plane and the longitudinal axis. The Gaussian PSF and the corresponding modulation transfer function (MTF) are compared against the actual PSF and MTF for validation. Results: The differences (errors) between the actual and estimated full-width half-max (FWHM) of the PSFs were 0.09 ± 0.05 and 0.14 ± 0.11 mm for the xy and z axes, respectively. The overall errors in the predicted frequencies measured at 75%, 50%, 25%, 10%, and 5% MTF levels were 0.06 ± 0.07 and 0.06 ± 0.04 cycles/mm for the xy and z axes, respectively. The accuracy of the estimates was dependent on whether they were reconstructed with a standard kernel (Toshiba's FC68, mean error of 0.06 ± 0.05 mm, MTF mean error 0.02 ± 0.02 cycles/mm) or a high resolution bone kernel (Toshiba's FC81, PSF FWHM error 0.12 ± 0.03 mm, MTF mean error 0.09 ± 0.08 cycles/mm). Conclusions: The method is accurate in 3D for an image reconstructed using a standard reconstruction kernel, which conforms to the Gaussian PSF assumption but less accurate when using a high resolution bone kernel. The method is a practical and self-contained means of estimating the PSF in clinical CT images featuring cortical bones, without the need phantoms or any prior knowledge about the scanner-specific parameters.

  2. DOE - Office of Legacy Management -- American Chain and Cable Co - CT 15

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth Dakota Edgemont, South Dakota,You are hereNY 01NJBrass Co - CT

  3. DOE - Office of Legacy Management -- Metals Selling Corp - CT 0-01

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth Dakota Edgemont,Manufacturing - OHSelling Corp - CT 0-01 FUSRAP

  4. Effect of the substrate temperature on the physical properties of molybdenum tri-oxide thin films obtained through the spray pyrolysis technique

    SciTech Connect (OSTI)

    Martinez, H.M.; Torres, J.; Lopez Carreno, L.D.; Rodriguez-Garcia, M.E.

    2013-01-15

    Polycrystalline molybdenum tri-oxide thin films were prepared using the spray pyrolysis technique; a 0.1 M solution of ammonium molybdate tetra-hydrated was used as a precursor. The samples were prepared on Corning glass substrates maintained at temperatures ranging between 423 and 673 K. The samples were characterized through micro Raman, X-ray diffraction, optical transmittance and DC electrical conductivity. The species MoO{sub 3} (H{sub 2}O){sub 2} was found in the sample prepared at a substrate temperature of 423 K. As the substrate temperature rises, the water disappears and the samples crystallize into {alpha}-MoO{sub 3}. The optical gap diminishes as the substrate temperature rises. Two electrical transport mechanisms were found: hopping under 200 K and intrinsic conduction over 200 K. The MoO{sub 3} films' sensitivity was analyzed for CO and H{sub 2}O in the temperature range 160 to 360 K; the results indicate that CO and H{sub 2}O have a reduction character. In all cases, it was found that the sensitivity to CO is lower than that to H{sub 2}O. - Highlights: Black-Right-Pointing-Pointer A low cost technique is used which produces good material. Black-Right-Pointing-Pointer Thin films are prepared using ammonium molybdate tetra hydrated. Black-Right-Pointing-Pointer The control of the physical properties of the samples could be done. Black-Right-Pointing-Pointer A calculation method is proposed to determine the material optical properties. Black-Right-Pointing-Pointer The MoO{sub 3} thin films prepared by spray pyrolysis could be used as gas sensor.

  5. SU-C-18A-05: Registration Accuracy of MR-Based Images to On-Board Megavoltage Cone-Beam CT for Brain Patient Setup

    SciTech Connect (OSTI)

    Pinnaduwage, D S; Chen, J; Descovich, M; Pouliot, J; Hwang, Ken-Ping

    2014-06-01

    Purpose: To quantify the difference in isocenter shifts when co-registering MR and MR-based pseudo CTs (pCT) with on-board megavoltage conebeam CT (CBCT) images. Methods: Fast Spoiled Gradient Echo MRs were used to generate pCTs (research version of Advantage Sim MD™, GE Healthcare) for ten patients who had prior brain radiotherapy. The planning CT (rCT) for each was co-registered with the MR, and the plan isocenter and two other reference points were transferred to the MR and pCT. CBCT images (with the machine isocenter) from a single treatment day were coregistered with the 3 test images (MR, pCT and rCT), by two observers and by an automated registration algorithm. The reference points were used to calculate patient shifts and rotations from the registrations. The shifts calculated from the test image registrations were compared to each other and to the shifts performed by the therapists who treated the patients on that day. Results: The average difference in absolute value between the isocenter shifts from the MR-, pCT- and rCT-CBCT registrations, and the therapist shifts, were 2.02, 3.01 and 0.89 mm (craniocaudal), 1.14, 1.34 and 0.46 mm (lateral), and 1.37, 3.43 and 1.43 mm (vertical), respectively. The MR- and pCT-CBCT registrations differed by 1.99, and 2.53 mm (craniocaudal), 1.36, and 1.37 mm (lateral), and 0.74 and 2.34 mm (vertical), respectively, from the average rCT-CBCT shifts. On average, differences of 2.39 (craniocaudal), 1.28 (lateral) and 2.84 mm (vertical) were seen between the MR and pCT shifts. Rotations relative to the CBCT coordinate system were on average <2° for the MR and rCT, and <6° for the pCT. Conclusion: In this study, FSPGR MR-CBCT registrations were more precise compared to the pCT-CBCT registrations. For improved accuracy, MR sequences that are optimal for bony anatomy visualization are necessary. GE healthcare has provided a research version of Advantage Sim MD to UCSF. No financial support was provided.

  6. SU-E-J-214: Comparative Assessment On IGRT On Partial Bladder Cancer Treatment Between CT-On-Rails (CTOR) and KV Cone Beam CT (CBCT)

    SciTech Connect (OSTI)

    Lin, T; Ma, C

    2014-06-01

    Purpose: Image-Guided radiation therapy(IGRT) depends on reliable online patient-specific anatomy information to address random and progressive anatomy changes. Large margins have been suggested to bladder cancer treatment due to large daily bladder anatomy variation. KV Cone beam CT(CBCT) has been used in IGRT localization prevalently; however, its lack of soft tissue contrast makes clinicians hesitate to perform daily soft tissue alignment with CBCT for partial bladder cancer treatment. This study compares the localization uncertainties of bladder cancer IGRT using CTon- Rails(CTOR) and CBCT. Methods: Three T2N0M0 bladder cancer patients (total of 66 Gy to partial bladder alone) were localized daily with either CTOR or CBCT for their entire treatment course. A total of 71 sets of CTOR and 22 sets of CBCT images were acquired and registered with original planning CT scans by radiation therapists and approved by radiation oncologists for the daily treatment. CTOR scanning entailed 2mm slice thickness, 0.98mm axial voxel size, 120kVp and 240mAs. CBCT used a half fan pelvis protocol from Varian OBI system with 2mm slice thickness, 0.98axial voxel size, 125kVp, and 680mAs. Daily localization distribution was compared. Accuracy of CTOR and CBCT on partial bladder alignment was also evaluated by comparing bladder PTV coverage. Results: 1cm all around PTV margins were used in every patient except target superior limit margin to 0mm due to bowel constraint. Daily shifts on CTOR averaged to 0.48, 0.24, 0.19 mms(SI,Lat,AP directions); CBCT averaged to 0.43, 0.09, 0.19 mms(SI,Lat,AP directions). The CTOR daily localization showed superior results of V100% of PTV(102% CTOR vs. 89% CBCT) and bowel(Dmax 69.5Gy vs. 78Gy CBCT). CTOR images showed much higher contrast on bladder PTV alignment. Conclusion: CTOR daily localization for IGRT is more dosimetrically beneficial for partial bladder cancer treatment than kV CBCT localization and provided better soft tissue PTV identification.

  7. Percutaneous Extraction of Cement Leakage After Vertebroplasty Under CT and Fluoroscopy Guidance: A New Technique

    SciTech Connect (OSTI)

    Amoretti, Nicolas Huwart, Laurent

    2012-12-15

    Purpose: We report a new minimally invasive technique of extraction of cement leakage following percutaneous vertebroplasty in adults. Methods: Seven adult patients (five women, two men; mean age: 81 years) treated for vertebral compression fractures by percutaneous vertebroplasty had cement leakage into perivertebral soft tissues along the needle route. Immediately after vertebroplasty, the procedure of extraction was performed under computed tomography (CT) and fluoroscopy guidance: a Chiba needle was first inserted using the same route as the vertebroplasty until contact was obtained with the cement fragment. This needle was then used as a guide for an 11-gauge Trocar t'am (Thiebaud, France). After needle withdrawal, a 13-gauge endoscopy clamp was inserted through the cannula to extract the cement fragments. The whole procedure was performed under local anesthesia. Results: In each patient, all cement fragments were withdrawn within 10 min, without complication. Conclusions: This report suggests that this CT- and fluoroscopy-guided percutaneous technique of extraction could reduce the rate of cement leakage-related complications.

  8. Sparse signal reconstruction from polychromatic X-ray CT measurements via mass attenuation discretization

    SciTech Connect (OSTI)

    Gu, Renliang; Dogandži?, Aleksandar [Iowa State University, Center for Nondestructive Evaluation, 1915 Scholl Road, Ames, IA 50011 (United States)

    2014-02-18

    We propose a method for reconstructing sparse images from polychromatic x-ray computed tomography (ct) measurements via mass attenuation coefficient discretization. The material of the inspected object and the incident spectrum are assumed to be unknown. We rewrite the Lambert-Beer’s law in terms of integral expressions of mass attenuation and discretize the resulting integrals. We then present a penalized constrained least-squares optimization approach for reconstructing the underlying object from log-domain measurements, where an active set approach is employed to estimate incident energy density parameters and the nonnegativity and sparsity of the image density map are imposed using negative-energy and smooth ?{sub 1}-norm penalty terms. We propose a two-step scheme for refining the mass attenuation discretization grid by using higher sampling rate over the range with higher photon energy, and eliminating the discretization points that have little effect on accuracy of the forward projection model. This refinement allows us to successfully handle the characteristic lines (Dirac impulses) in the incident energy density spectrum. We compare the proposed method with the standard filtered backprojection, which ignores the polychromatic nature of the measurements and sparsity of the image density map. Numerical simulations using both realistic simulated and real x-ray ct data are presented.

  9. CT14QED PDFs from Isolated Photon Production in Deep Inelastic Scattering

    E-Print Network [OSTI]

    Carl Schmidt; Jon Pumplin; Daniel Stump; C. -P. Yuan

    2015-09-09

    We describe the implementation of Quantum Electrodynamic (QED) evolution at Leading Order (LO) along with Quantum Chromodynamic (QCD) evolution at Next-to-Leading Order (NLO) in the CTEQ-TEA Global analysis package. The photon Parton Distribution Function (PDF) is described by a two-parameter ansatz, coming from radiation off the valence quarks, and based on the CT14 NLO PDFs. Setting the two parameters equal, allows us to completely specify the photon PDF in terms of the momentum fraction carried by the photon, $p_0^\\gamma$, at the initial scale $Q_0=1.295$ GeV. We obtain constraints on the photon PDF by comparing with ZEUS data~\\cite{Chekanov:2009dq} on the production of isolated photons in deep inelastic scattering, $ep\\rightarrow e\\gamma+X$. For this comparison we present a new perturbative calculation of the process that consistently combines the photon-initiated contribution with the quark-initiated contribution. Comparison with the data allows us to put a constraint at the 90% confidence level of $p_0^\\gamma\\lesssim0.14\\%$ for the photon PDF at the initial scale of $Q_0=1.295$ GeV in the one-parameter radiative ansatz. The resulting CT14QED PDFs will be made available to the public.

  10. SU-E-I-25: Determining Tube Current, Tube Voltage and Pitch Suitable for Low- Dose Lung Screening CT

    SciTech Connect (OSTI)

    Williams, K; Matthews, K

    2014-06-01

    Purpose: The quality of a computed tomography (CT) image and the dose delivered during its acquisition depend upon the acquisition parameters used. Tube current, tube voltage, and pitch are acquisition parameters that potentially affect image quality and dose. This study investigated physicians' abilities to characterize small, solid nodules in low-dose CT images for combinations of current, voltage and pitch, for three CT scanner models. Methods: Lung CT images was acquired of a Data Spectrum anthropomorphic torso phantom with various combinations of pitch, tube current, and tube voltage; this phantom was used because acrylic beads of various sizes could be placed within the lung compartments to simulate nodules. The phantom was imaged on two 16-slice scanners and a 64-slice scanner. The acquisition parameters spanned a range of estimated CTDI levels; the CTDI estimates from the acquisition software were verified by measurement. Several experienced radiologists viewed the phantom lung CT images and noted nodule location, size and shape, as well as the acceptability of overall image quality. Results: Image quality for assessment of nodules was deemed unsatisfactory for all scanners at 80 kV (any tube current) and at 35 mA (any tube voltage). Tube current of 50 mA or more at 120 kV resulted in similar assessments from all three scanners. Physician-measured sphere diameters were closer to actual diameters for larger spheres, higher tube current, and higher kV. Pitch influenced size measurements less for larger spheres than for smaller spheres. CTDI was typically overestimated by the scanner software compared to measurement. Conclusion: Based on this survey of acquisition parameters, a low-dose CT protocol of 120 kV, 50 mA, and pitch of 1.4 is recommended to balance patient dose and acceptable image quality. For three models of scanners, this protocol resulted in estimated CTDIs from 2.9–3.6 mGy.

  11. Radiofrequency Ablation Assisted by Real-Time Virtual Sonography and CT for Hepatocellular Carcinoma Undetectable by Conventional Sonography

    SciTech Connect (OSTI)

    Nakai, Motoki, E-mail: momonga@wakayama-med.ac.jp; Sato, Morio; Sahara, Shinya; Takasaka, Isao; Kawai, Nobuyuki; Minamiguchi, Hiroki; Tanihata, Hirohiko; Kimura, Masashi [Wakayama Medical University, Department of Radiology (Japan); Takeuchi, Nozomu [Hidaka General Hospital, Department of Radiology (Japan)

    2009-01-15

    Real-time virtual sonography (RVS) is a diagnostic imaging support system, which provides the same cross-sectional multiplanar reconstruction images as ultrasound images on the same monitor screen in real time. The purpose of this study was to evaluate radiofrequency ablation (RFA) assisted by RVS and CT for hepatocellular carcinoma (HCC) undetectable with conventional sonography. Subjects were 20 patients with 20 HCC nodules not detected by conventional sonography but detectable by CT or MRI. All patients had hepatitis C-induced liver cirrhosis; there were 13 males and 7 females aged 55-81 years (mean, 69.3 years). RFA was performed in the CT room, and the tumor was punctured with the assistance of RVS. CT was performed immediately after puncture, and ablation was performed after confirming that the needle had been inserted into the tumor precisely. The mean number of punctures and success rates of the first puncture were evaluated. Treatment effects were evaluated with dynamic CT every 3 months after RFA. RFA was technically feasible and local tumor control was achieved in all patients. The mean number of punctures was 1.1, and the success rate of the first puncture was 90.0%. This method enabled safe ablation without complications. The mean follow-up period was 13.5 month (range, 9-18 months). No local recurrence was observed at the follow-up points. In conclusion, RFA assisted by RVS and CT is a safe and efficacious method of treatment for HCC undetectable by conventional sonography.

  12. Patients with Life-Threatening Arterial Renal Hemorrhage: CT Angiography and Catheter Angiography with Subsequent Superselective Embolization

    SciTech Connect (OSTI)

    Sommer, C. M., E-mail: christof.sommer@med.uni-heidelberg.de; Stampfl, U.; Bellemann, N.; Ramsauer, S. [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology (Germany); Loenard, B. M. [University Hospital Heidelberg, Department of Urology (Germany); Haferkamp, A. [University Hospital Heidelberg, Department of Anesthesiology (Germany); Hallscheidt, P.; Richter, G. M.; Kauczor, H. U.; Radeleff, B. A. [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology (Germany)

    2010-06-15

    The purpose of this study was to evaluate the technical and clinical success of superselective embolization in patients with life-threatening arterial renal hemorrhage undergoing preinterventional CT angiography. Forty-three patients with clinical signs of life-threatening arterial renal hemorrhage underwent CT angiography and catheter angiography. Superselective embolization was indicated in the case of a positive catheter angiography. Primary study goals were technical and clinical success of superselective embolization. Secondary study goals were CT angiographic and catheter angiographic image findings and clinical follow-up. The mean time interval between CT angiography and catheter angiography was 8.3 {+-} 10.3 h (range, 0.2-34.1 h). Arterial renal hemorrhage was identified with CT angiography in 42 of 43 patients (98%) and catheter angiography in 39 of 43 patients (91%) (overview angiography in 4 of 43 patients [9%], selective angiography in 16 of 43 patients [37%], and superselective angiography in 39 of 43 patients [91%]). Superselective embolization was performed in 39 of 43 patients (91%) and technically successful in 37 of 39 patients (95%). Therefore, coil embolization was performed in 13 of 37 patients (35%), liquid embolization in 9 of 37 patients (24%), particulate embolization in 1 of 37 patients (3%), and a combination in 14 of 37 patients (38%). Clinical failure occurred in 8 of 39 patients (21%) and procedure-related complications in 2 of 39 patients (5%). The 30-day mortality rate was 3%. Hemoglobin decreased significantly prior to intervention (P < 0.001) and increased significantly after intervention (P < 0.005). In conclusion, superselective embolization is effective, reliable, and safe in patients with life-threatening arterial renal hemorrhage. In contrast to overview and selective angiography, only superselective angiography allows reliable detection of arterial renal hemorrhage. Preinterventional CT angiography is excellent for detection and localization of arterial renal hemorrhage and appropriate for guidance of the embolization procedure.

  13. Chun Jiao, Dongming Wang, Hongbing Lu*, Member, IEEE, Zhu Zhang, Jerome Z. Liang, Fellow, IEEE AbstractLow-dose protocol for computed tomography (CT)

    E-Print Network [OSTI]

    higher risk of lung cancer, and that of children. To lower the radiation exposure, low-dose protocols Abstract­Low-dose protocol for computed tomography (CT) scans has been gradually used in clinics to lower-stationary Gaussian noise in low-dose CT sinograms by wavelet analysis. To explore the noise property in wavelet

  14. Cleaning Supplies Manufacturer/Supplier Gen Peds GI ETC US CT MRI BI Ortho FCC Angio PET A33 Dry Airkem X

    E-Print Network [OSTI]

    Cleaning Supplies Manufacturer/Supplier Gen Peds GI ETC US CT MRI BI Ortho FCC Angio PET NUC MED A\\MSDS.xls #12;Cleaning Supplies Manufacturer/Supplier Gen Peds GI ETC US CT MRI BI Ortho FCC Angio PET NUC MED

  15. A hybrid approach for rapid, accurate, and direct kilovoltage radiation dose calculations in CT voxel space

    SciTech Connect (OSTI)

    Kouznetsov, Alexei; Tambasco, Mauro

    2011-03-15

    Purpose: To develop and validate a fast and accurate method that uses computed tomography (CT) voxel data to estimate absorbed radiation dose at a point of interest (POI) or series of POIs from a kilovoltage (kV) imaging procedure. Methods: The authors developed an approach that computes absorbed radiation dose at a POI by numerically evaluating the linear Boltzmann transport equation (LBTE) using a combination of deterministic and Monte Carlo (MC) techniques. This hybrid approach accounts for material heterogeneity with a level of accuracy comparable to the general MC algorithms. Also, the dose at a POI is computed within seconds using the Intel Core i7 CPU 920 2.67 GHz quad core architecture, and the calculations are performed using CT voxel data, making it flexible and feasible for clinical applications. To validate the method, the authors constructed and acquired a CT scan of a heterogeneous block phantom consisting of a succession of slab densities: Tissue (1.29 cm), bone (2.42 cm), lung (4.84 cm), bone (1.37 cm), and tissue (4.84 cm). Using the hybrid transport method, the authors computed the absorbed doses at a set of points along the central axis and x direction of the phantom for an isotropic 125 kVp photon spectral point source located along the central axis 92.7 cm above the phantom surface. The accuracy of the results was compared to those computed with MCNP, which was cross-validated with EGSnrc, and served as the benchmark for validation. Results: The error in the depth dose ranged from -1.45% to +1.39% with a mean and standard deviation of -0.12% and 0.66%, respectively. The error in the x profile ranged from -1.3% to +0.9%, with standard deviations of -0.3% and 0.5%, respectively. The number of photons required to achieve these results was 1x10{sup 6}. Conclusions: The voxel-based hybrid method evaluates the LBTE rapidly and accurately to estimate the absorbed x-ray dose at any POI or series of POIs from a kV imaging procedure.

  16. SU-E-I-62: Assessing Radiation Dose Reduction and CT Image Optimization Through the Measurement and Analysis of the Detector Quantum Efficiency (DQE) of CT Images Using Different Beam Hardening Filters

    SciTech Connect (OSTI)

    Collier, J; Aldoohan, S; Gill, K

    2014-06-01

    Purpose: Reducing patient dose while maintaining (or even improving) image quality is one of the foremost goals in CT imaging. To this end, we consider the feasibility of optimizing CT scan protocols in conjunction with the application of different beam-hardening filtrations and assess this augmentation through noise-power spectrum (NPS) and detector quantum efficiency (DQE) analysis. Methods: American College of Radiology (ACR) and Catphan phantoms (The Phantom Laboratory) were scanned with a 64 slice CT scanner when additional filtration of thickness and composition (e.g., copper, nickel, tantalum, titanium, and tungsten) had been applied. A MATLAB-based code was employed to calculate the image of noise NPS. The Catphan Image Owl software suite was then used to compute the modulated transfer function (MTF) responses of the scanner. The DQE for each additional filter, including the inherent filtration, was then computed from these values. Finally, CT dose index (CTDIvol) values were obtained for each applied filtration through the use of a 100 mm pencil ionization chamber and CT dose phantom. Results: NPS, MTF, and DQE values were computed for each applied filtration and compared to the reference case of inherent beam-hardening filtration only. Results showed that the NPS values were reduced between 5 and 12% compared to inherent filtration case. Additionally, CTDIvol values were reduced between 15 and 27% depending on the composition of filtration applied. However, no noticeable changes in image contrast-to-noise ratios were noted. Conclusion: The reduction in the quanta noise section of the NPS profile found in this phantom-based study is encouraging. The reduction in both noise and dose through the application of beam-hardening filters is reflected in our phantom image quality. However, further investigation is needed to ascertain the applicability of this approach to reducing patient dose while maintaining diagnostically acceptable image qualities in a clinical setting.

  17. Abstract--Proton computed tomography (pCT) has the potential to improve the accuracy of dose calculations for proton

    E-Print Network [OSTI]

    Mueller, Klaus

    Abstract--Proton computed tomography (pCT) has the potential to improve the accuracy of dose calculations for proton treatment planning, and will also be useful for pretreatment verification of patient positioning relative to the proton beam. A design study was performed to define the optimal approach to a p

  18. Spiral CT of the thoracic aorta with 3-D volume rendering: A pictorial review of current applications

    SciTech Connect (OSTI)

    Wu, Christine M.; Urban, Bruce A.; Fishman, Elliot K. [The Johns Hopkins University School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science (United States)

    1999-03-15

    ConclusionSpiral CT represents an excellent noninvasive technique for acquiring data to create 3-D angiographic maps of the aorta. Coupling the data sets with 3-D imaging provides new and exciting capabilities for aortic imaging in a potentially more correct and accurate fashion.

  19. Chapter 7 1. Evaluate the path integral ? x + y + z ds, c(t) = (sint,cost ...

    E-Print Network [OSTI]

    2015-04-30

    Evaluate the path integral. ? c x + y + z ds, c(t) = (sint,cost, t),t ? [0,2?]. Solution. ? c x + y + z ds = ? 2?. 0. (sint + cost + t). ? cos2 t + sin2 t + 1dt. = ?. 2. ? 2?.

  20. Blockwise Classification of Lung Patterns in Unsegmented CT Images Luiza D. Bagesteiro, Lucas F. Oliveira and Daniel Weingaertner

    E-Print Network [OSTI]

    Blockwise Classification of Lung Patterns in Unsegmented CT Images Luiza D. Bagesteiro, Lucas F}@inf.ufpr.br Abstract--Diagnosis of lung diseases is usually accomplished by detecting abnormal characteristics-Resolution lung CTs using the Com- pleted Local Binary Pattern (CLBP) descriptor with a Support Vector Machine

  1. EVALUATION OF GEOMETRIC FEATURE DESCRIPTORS FOR DETECTION AND CLASSIFICATION OF LUNG NODULES IN LOW DOSE CT SCANS OF THE CHEST

    E-Print Network [OSTI]

    Louisville, University of

    EVALUATION OF GEOMETRIC FEATURE DESCRIPTORS FOR DETECTION AND CLASSIFICATION OF LUNG NODULES IN LOW descriptors, common in computer vision, for false positive reduction and for classification of lung nodules in low dose CT (LDCT) scans. A data-driven lung nodule modeling approach creates templates for common

  2. Evaluation of Radiation Dose Reduction during CT Scans Using Oxide Bismuth and Nano-Barium Sulfate Shields

    E-Print Network [OSTI]

    Seoung, Youl-Hun

    2015-01-01

    The purpose of the present study was to evaluate radiation dose reduction and image quality during CT scanning by using a new dose reduction fiber sheet (DRFS) with commercially available bismuth shields. These DRFS were composed of nano-barium sulfate (BaSO4), filling the gaps left by the large oxide bismuth (Bi2O3) particle sizes. The radiation dose was measured five times at directionss of 12 o'clock from the center of the polymethyl methacrylate (PMMA) head phantom to calculate an average value using a CT ionization chamber. The image quality measured CT transverse images of the PMMA head phantom depending on X-ray tube voltages and the type of shielding. Two regions of interest in CT transverse images were chosen from the right and left areas under the surface of the PMMA head phantom and from ion chamber holes located at directions of 12 o'clock from the center of the PMMA head phantom. The results of this study showed that the new DRFS shields could reduce dosages to 15.61%, 23.05%, and 22.71% more in ...

  3. CtIP tetramer assembly is required for DNA-end resection and repair

    E-Print Network [OSTI]

    Davies, Owen R.; Forment, Josep V.; Sun, Meidai; Belotserkovskaya, Rimma; Coates, Julia; Galanty, Yaron; Demir, Mukerrem; Morton, Christopher; Rzechorzek, Neil; Jackson, Stephen P.; Pellegrini, Luca

    2015-01-05

    of reservoir solution (200 mM lithium sulphate, 100 mM sodium acetate pH 3.6, 32% (v/v) PEG 400) and equilibrated for 7-10 days. Suitable crystals were incubated in cryoprotectant (20 mM Tris pH 8.0, 150 mM sodium chloride, 200 mM lithium sulphate, 100 m... protocol22. CtIP recombinant protein samples at 0.5-0.1 mg/ml were digested with 0.6 µg/µl proteinase K (NEB) at 60°C for 1 hour. For each digested protein sample, in addition to standard solutions containing 0-100 µM zinc acetate, 10 µl of supernatant...

  4. CT of the liver and spleen with EOE-13: review of 225 examinations

    SciTech Connect (OSTI)

    Miller, D.L.; Vermess, M.; Doppman, J.L.; Simon, R.M.; Sugarbaker, P.H.; O'Leary, T.J.; Grimes, G.; Chatterji, D.G.; Willis, M.

    1984-08-01

    EOE-13 is an experimental liver-spleen-specific computed tomographic (CT) contrast agent developed at the National Institutes of Health. Experience with this agent in 225 clinical examinations is described. On average, use of EOE-13 increases the attenuation of normal liver by 32.5 H and that of normal spleen by 52.3 H. Tumors in these organs increase only 2.6 H, making them more easily detectable. Most of the iodine in EOE-13 appears to clear from the liver and spleen by 24 hr after injection. No deaths or permanent morbidity have been observed. The complication rate is 3.6%. EOE-13 is valuable for the detection of hepatic and splenic tumors.

  5. Level-set segmentation of pulmonary nodules in megavolt electronic portal images using a CT prior

    SciTech Connect (OSTI)

    Schildkraut, J. S.; Prosser, N.; Savakis, A.; Gomez, J.; Nazareth, D.; Singh, A. K.; Malhotra, H. K.

    2010-11-15

    Purpose: Pulmonary nodules present unique problems during radiation treatment due to nodule position uncertainty that is caused by respiration. The radiation field has to be enlarged to account for nodule motion during treatment. The purpose of this work is to provide a method of locating a pulmonary nodule in a megavolt portal image that can be used to reduce the internal target volume (ITV) during radiation therapy. A reduction in the ITV would result in a decrease in radiation toxicity to healthy tissue. Methods: Eight patients with nonsmall cell lung cancer were used in this study. CT scans that include the pulmonary nodule were captured with a GE Healthcare LightSpeed RT 16 scanner. Megavolt portal images were acquired with a Varian Trilogy unit equipped with an AS1000 electronic portal imaging device. The nodule localization method uses grayscale morphological filtering and level-set segmentation with a prior. The treatment-time portion of the algorithm is implemented on a graphical processing unit. Results: The method was retrospectively tested on eight cases that include a total of 151 megavolt portal image frames. The method reduced the nodule position uncertainty by an average of 40% for seven out of the eight cases. The treatment phase portion of the method has a subsecond execution time that makes it suitable for near-real-time nodule localization. Conclusions: A method was developed to localize a pulmonary nodule in a megavolt portal image. The method uses the characteristics of the nodule in a prior CT scan to enhance the nodule in the portal image and to identify the nodule region by level-set segmentation. In a retrospective study, the method reduced the nodule position uncertainty by an average of 40% for seven out of the eight cases studied.

  6. A low dose simulation tool for CT systems with energy integrating detectors

    SciTech Connect (OSTI)

    Zabic, Stanislav; Morton, Thomas; Brown, Kevin M.; Wang Qiu

    2013-03-15

    Purpose: This paper introduces a new strategy for simulating low-dose computed tomography (CT) scans using real scans of a higher dose as an input. The tool is verified against simulations and real scans and compared to other approaches found in the literature. Methods: The conditional variance identity is used to properly account for the variance of the input high-dose data, and a formula is derived for generating a new Poisson noise realization which has the same mean and variance as the true low-dose data. The authors also derive a formula for the inclusion of real samples of detector noise, properly scaled according to the level of the simulated x-ray signals. Results: The proposed method is shown to match real scans in number of experiments. Noise standard deviation measurements in simulated low-dose reconstructions of a 35 cm water phantom match real scans in a range from 500 to 10 mA with less than 5% error. Mean and variance of individual detector channels are shown to match closely across the detector array. Finally, the visual appearance of noise and streak artifacts is shown to match in real scans even under conditions of photon-starvation (with tube currents as low as 10 and 80 mA). Additionally, the proposed method is shown to be more accurate than previous approaches (1) in achieving the correct mean and variance in reconstructed images from pure-Poisson noise simulations (with no detector noise) under photon-starvation conditions, and (2) in simulating the correct noise level and detector noise artifacts in real low-dose scans. Conclusions: The proposed method can accurately simulate low-dose CT data starting from high-dose data, including effects from photon starvation and detector noise. This is potentially a very useful tool in helping to determine minimum dose requirements for a wide range of clinical protocols and advanced reconstruction algorithms.

  7. CT imaging during microwave ablation: Analysis of spatial and temporal tissue contraction

    SciTech Connect (OSTI)

    Liu, Dong; Brace, Christopher L., E-mail: clbrace@wisc.edu [Departments of Radiology and Biomedical Engineering, University of Wisconsin, Madison, Wisconsin 53705 (United States)

    2014-11-01

    Purpose: To analyze the spatial distribution and temporal development of liver tissue contraction during high-temperature ablation by using intraprocedural computed tomography (CT) imaging. Methods: A total of 46 aluminum fiducial markers were positioned in a 60 × 45 mm grid, in a single plane, around a microwave ablation antenna in each of six ex vivo bovine liver samples. Ablations were performed for 10 min at 100 W. CT data of the liver sample were acquired every 30 s during ablation. Fiducial motion between acquisitions was tracked in postprocessing and used to calculate measures of tissue contraction and contraction rates. The spatial distribution and temporal evolution of contraction were analyzed. Results: Fiducial displacement indicated that the zone measured postablation was 8.2 ± 1.8 mm (?20%) smaller in the radial direction and 7.1 ± 1.0 mm (?10%) shorter in the longitudinal direction than the preablation tissue dimension. Therefore, the total ablation volume was reduced from its preablation value by approximately 45%. Very little longitudinal contraction was noted in the distal portion of the ablation zone. Central tissues contracted more than 60%, which was near an estimated limit of ?70% based on initial water content. More peripheral tissues contracted only 15% in any direction. Contraction rates peaked during the first 60 s of heating with a roughly exponential decay over time. Conclusions: Ablation zones measured posttreatment are significantly smaller than the pretreatment tissue dimensions. Tissue contraction is spatially dependent, with the greatest effect occurring in the central ablation zone. Contraction rate peaks early and decays over time.

  8. TU-F-18A-02: Iterative Image-Domain Decomposition for Dual-Energy CT

    SciTech Connect (OSTI)

    Niu, T; Dong, X; Petrongolo, M; Zhu, L

    2014-06-15

    Purpose: Dual energy CT (DECT) imaging plays an important role in advanced imaging applications due to its material decomposition capability. Direct decomposition via matrix inversion suffers from significant degradation of image signal-to-noise ratios, which reduces clinical value. Existing de-noising algorithms achieve suboptimal performance since they suppress image noise either before or after the decomposition and do not fully explore the noise statistical properties of the decomposition process. We propose an iterative image-domain decomposition method for noise suppression in DECT, using the full variance-covariance matrix of the decomposed images. Methods: The proposed algorithm is formulated in the form of least-square estimation with smoothness regularization. It includes the inverse of the estimated variance-covariance matrix of the decomposed images as the penalty weight in the least-square term. Performance is evaluated using an evaluation phantom (Catphan 600) and an anthropomorphic head phantom. Results are compared to those generated using direct matrix inversion with no noise suppression, a de-noising method applied on the decomposed images, and an existing algorithm with similar formulation but with an edge-preserving regularization term. Results: On the Catphan phantom, our method retains the same spatial resolution as the CT images before decomposition while reducing the noise standard deviation of decomposed images by over 98%. The other methods either degrade spatial resolution or achieve less low-contrast detectability. Also, our method yields lower electron density measurement error than direct matrix inversion and reduces error variation by over 97%. On the head phantom, it reduces the noise standard deviation of decomposed images by over 97% without blurring the sinus structures. Conclusion: We propose an iterative image-domain decomposition method for DECT. The method combines noise suppression and material decomposition into an iterative process and achieves both goals simultaneously. The proposed algorithm shows superior performance on noise suppression with high image spatial resolution and low-contrast detectability. This work is supported by a Varian MRA grant.

  9. Inter-slice bidirectional registration-based segmentation of the prostate gland in MR and CT image sequences

    SciTech Connect (OSTI)

    Khalvati, Farzad Tizhoosh, Hamid R.; Salmanpour, Aryan; Rahnamayan, Shahryar; Rodrigues, George

    2013-12-15

    Purpose: Accurate segmentation and volume estimation of the prostate gland in magnetic resonance (MR) and computed tomography (CT) images are necessary steps in diagnosis, treatment, and monitoring of prostate cancer. This paper presents an algorithm for the prostate gland volume estimation based on the semiautomated segmentation of individual slices in T2-weighted MR and CT image sequences. Methods: The proposedInter-Slice Bidirectional Registration-based Segmentation (iBRS) algorithm relies on interslice image registration of volume data to segment the prostate gland without the use of an anatomical atlas. It requires the user to mark only three slices in a given volume dataset, i.e., the first, middle, and last slices. Next, the proposed algorithm uses a registration algorithm to autosegment the remaining slices. We conducted comprehensive experiments to measure the performance of the proposed algorithm using three registration methods (i.e., rigid, affine, and nonrigid techniques). Results: The results with the proposed technique were compared with manual marking using prostate MR and CT images from 117 patients. Manual marking was performed by an expert user for all 117 patients. The median accuracies for individual slices measured using the Dice similarity coefficient (DSC) were 92% and 91% for MR and CT images, respectively. The iBRS algorithm was also evaluated regarding user variability, which confirmed that the algorithm was robust to interuser variability when marking the prostate gland. Conclusions: The proposed algorithm exploits the interslice data redundancy of the images in a volume dataset of MR and CT images and eliminates the need for an atlas, minimizing the computational cost while producing highly accurate results which are robust to interuser variability.

  10. Assessment of contrast enhanced respiration managed cone-beam CT for image guided radiotherapy of intrahepatic tumors

    SciTech Connect (OSTI)

    Jensen, Nikolaj K. G.; Stewart, Errol; Imaging Research Lab, Robarts Research Institute, London, Ontario N6A 5B7; Imaging Program, Lawson Health Research Institute, London, Ontario N6C 2R5 ; Lock, Michael; Fisher, Barbara; Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6 ; Kozak, Roman; Chen, Jeff; Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6; Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 ; Lee, Ting-Yim; Imaging Research Lab, Robarts Research Institute, London, Ontario N6A 5B7; Imaging Program, Lawson Health Research Institute, London, Ontario N6C 2R5; Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6; Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1 ; Wong, Eugene; Department of Oncology, University of Western Ontario, London, Ontario N6A 4L6; Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 5C1; Department of Physics and Astronomy, University of Western Ontario, London, Ontario N6A 3K7

    2014-05-15

    Purpose: Contrast enhancement and respiration management are widely used during image acquisition for radiotherapy treatment planning of liver tumors along with respiration management at the treatment unit. However, neither respiration management nor intravenous contrast is commonly used during cone-beam CT (CBCT) image acquisition for alignment prior to radiotherapy. In this study, the authors investigate the potential gains of injecting an iodinated contrast agent in combination with respiration management during CBCT acquisition for liver tumor radiotherapy. Methods: Five rabbits with implanted liver tumors were subjected to CBCT with and without motion management and contrast injection. The acquired CBCT images were registered to the planning CT to determine alignment accuracy and dosimetric impact. The authors developed a simulation tool for simulating contrast-enhanced CBCT images from dynamic contrast enhanced CT imaging (DCE-CT) to determine optimal contrast injection protocols. The tool was validated against contrast-enhanced CBCT of the rabbit subjects and was used for five human patients diagnosed with hepatocellular carcinoma. Results: In the rabbit experiment, when neither motion management nor contrast was used, tumor centroid misalignment between planning image and CBCT was 9.2 mm. This was reduced to 2.8?mm when both techniques were employed. Tumors were not visualized in clinical CBCT images of human subjects. Simulated contrast-enhanced CBCT was found to improve tumor contrast in all subjects. Different patients were found to require different contrast injections to maximize tumor contrast. Conclusions: Based on the authors’ animal study, respiration managed contrast enhanced CBCT improves IGRT significantly. Contrast enhanced CBCT benefits from patient specific tracer kinetics determined from DCE-CT.

  11. Ranchero Armature Test LA-19.4-CT-3: PBX-9501 Explosive with no smoothing layer. Firing point 88, 9/16/13

    SciTech Connect (OSTI)

    Glover, Brian B.; Goforth, James H.; Rae, Philip John; Dickson, Peter; Briggs, Matthew E.; Marr-Lyon, Mark; Hare, Steven John; Herrera, Dennis Harold; Watt, Robert Gregory; Rousculp, Christopher L.

    2014-11-13

    LA-19.4-CT-3 (CT-3) was the third camera test in a series beginning in 1/11, which diagnose the performance of 6 mm thick, 6061 T-0 Al Ranchero armatures. [The test LA-43-CT-2 (CT-2) is described in LA-UR-14-21983.] The goal of CT-3 was to verify that PBX-9501, with 18 mm point spacing and no smoothing layer, could be used for Ranchero generator armatures in place of PBXN-110, which had been used in all previous Ranchero applications. CT-1 and CT-2 both had 43 cm long slapper detonator systems imbedded in the cast PBXN-110 explosive, but manufacturing a charge for a similar 9501 test was not cost effective. Instead, a single cylinder of 9501, 19.368 cm long and 15.494 cm (6.100”)in diameter, had a groove machined to accommodate a row of 11 SE-1 detonators with 18 mm point spacing along the mid-plane of the cylinder. The expansion of the armature looks like a slapper assembly along almost ½ of the circumference, and provides adequate proof of concept. Removing the smoother from PBXN-110-driven armatures increased the armature velocity from 3.1 mm/?s to 3.3 mm/?s, as seen in CT-2, and the velocity measured on CT-3 increased to 3.8 mm/?s. In addition, the camera records show that the surface of the armature is smooth enough, and free from ruptures for an expansion of greater that 2X. The advantage of using 9501 is that it precludes concerns about blow-outs seen when bubbles are left in the cast material, and gives extra velocity. The disadvantage is that the machined explosives are more expensive.

  12. SU-E-J-218: Evaluation of CT Images Created Using a New Metal Artifact Reduction Reconstruction Algorithm for Radiation Therapy Treatment Planning

    SciTech Connect (OSTI)

    Niemkiewicz, J; Palmiotti, A; Miner, M; Stunja, L; Bergene, J [Lehigh Valley Health Network, Allentown, PA (United States)

    2014-06-01

    Purpose: Metal in patients creates streak artifacts in CT images. When used for radiation treatment planning, these artifacts make it difficult to identify internal structures and affects radiation dose calculations, which depend on HU numbers for inhomogeneity correction. This work quantitatively evaluates a new metal artifact reduction (MAR) CT image reconstruction algorithm (GE Healthcare CT-0521-04.13-EN-US DOC1381483) when metal is present. Methods: A Gammex Model 467 Tissue Characterization phantom was used. CT images were taken of this phantom on a GE Optima580RT CT scanner with and without steel and titanium plugs using both the standard and MAR reconstruction algorithms. HU values were compared pixel by pixel to determine if the MAR algorithm altered the HUs of normal tissues when no metal is present, and to evaluate the effect of using the MAR algorithm when metal is present. Also, CT images of patients with internal metal objects using standard and MAR reconstruction algorithms were compared. Results: Comparing the standard and MAR reconstructed images of the phantom without metal, 95.0% of pixels were within ±35 HU and 98.0% of pixels were within ±85 HU. Also, the MAR reconstruction algorithm showed significant improvement in maintaining HUs of non-metallic regions in the images taken of the phantom with metal. HU Gamma analysis (2%, 2mm) of metal vs. non-metal phantom imaging using standard reconstruction resulted in an 84.8% pass rate compared to 96.6% for the MAR reconstructed images. CT images of patients with metal show significant artifact reduction when reconstructed with the MAR algorithm. Conclusion: CT imaging using the MAR reconstruction algorithm provides improved visualization of internal anatomy and more accurate HUs when metal is present compared to the standard reconstruction algorithm. MAR reconstructed CT images provide qualitative and quantitative improvements over current reconstruction algorithms, thus improving radiation treatment planning accuracy.

  13. An HRTEM investigation of the metastable low-temperature silica phase opal-CT in cherts and porcelanites from the Monterey Formation, CA

    SciTech Connect (OSTI)

    Cady, S.L.; Wenk, H.R. )

    1992-01-01

    High resolution transmission electron microscopy (HRTEM) is used to investigate the metastable low-temperature silica phase opal-CT in cherts and porcelanites from the Miocene Monterey Formation of California. Low-dose imaging techniques developed to image highly beam sensitive proteins were used in this study and have resulted in good phase contrast images of this hydrous silica phase. Detailed X-ray powder diffraction studies of stratigraphically equivalent rocks along the Santa Barbara coast indicate that the primary d-spacing of newly formed opal-CT differs in rocks with different ratios of silica and detrital minerals. Opal-CT forms progressively later and with a smaller primary d-spacing in rocks with increasing amounts of detrital minerals. In siliceous cherts opal-CT occurs as long needles that most often form dense spherulitic fiber bundles which are randomly dispersed within the rock matrix. The random orientation of fiber bundle nucleation centers does not appear to be associated with any obvious nucleation site, unlike the length-slow opal-CT fibers known as lussatite. Opal-CT needles produce optical diffractogram patterns that are compatible with tridymite and crystobalite. Streaking in the diffraction pattern of individual needles is attributed to a high density of planar defects parallel to their length. Planar defects are not as abundant in opal-CT needles formed in detrital-rich rocks suggesting the rapid growth of opal-CT in highly siliceous environments results in a greater proportion of stacking disorder in the needles. HRTEM provides a method for investigating the development of the microstructure of opal-CT during diagenesis.

  14. A One-Step Cone-Beam CT-Enabled Planning-to-Treatment Model for Palliative Radiotherapy-From Development to Implementation

    SciTech Connect (OSTI)

    Wong, Rebecca K.S.; Letourneau, Daniel; Varma, Anita; Department of Radiation Oncology, University of Toronto, Toronto, Ontario ; Bissonnette, Jean Pierre; Fitzpatrick, David; Grabarz, Daniel; Elder, Christine; Martin, Melanie; Bezjak, Andrea; Department of Radiation Oncology, University of Toronto, Toronto, Ontario ; Panzarella, Tony; Gospodarowicz, Mary; Department of Radiation Oncology, University of Toronto, Toronto, Ontario ; Jaffray, David A.; Department of Radiation Oncology, University of Toronto, Toronto, Ontario; Department of Medical Biophysics, University of Toronto, Toronto, Ontario

    2012-11-01

    Purpose: To develop a cone-beam computed tomography (CT)-enabled one-step simulation-to-treatment process for the treatment of bone metastases. Methods and Materials: A three-phase prospective study was conducted. Patients requiring palliative radiotherapy to the spine, mediastinum, or abdomen/pelvis suitable for treatment with simple beam geometry ({<=}2 beams) were accrued. Phase A established the accuracy of cone-beam CT images for the purpose of gross tumor target volume (GTV) definition. Phase B evaluated the feasibility of implementing the cone-beam CT-enabled planning process at the treatment unit. Phase C evaluated the online cone-beam CT-enabled process for the planning and treatment of patients requiring radiotherapy for bone metastases. Results: Eighty-four patients participated in this study. Phase A (n = 9) established the adequacy of cone-beam CT images for target definition. Phase B (n = 45) established the quality of treatment plans to be adequate for clinical implementation for bone metastases. When the process was applied clinically in bone metastases (Phase C), the degree of overlap between planning computed tomography (PCT) and cone-beam CT for GTV and between PCT and cone-beam CT for treatment field was 82% {+-} 11% and 97% {+-} 4%, respectively. The oncologist's decision to accept the plan under a time-pressured environment remained of high quality, with the cone-beam CT-generated treatment plan delivering at least 90% of the prescribed dose to 100% {+-} 0% of the cone-beam CT planning target volume (PTV). With the assumption that the PCT PTV is the gold-standard target, the cone-beam CT-generated treatment plan delivered at least 90% and at least 95% of dose to 98% {+-} 2% and 97% {+-} 5% of the PCT PTV, respectively. The mean time for the online planning and treatment process was 32.7 {+-} 4.0 minutes. Patient satisfaction was high, with a trend for superior satisfaction with the cone-beam CT-enabled process. Conclusions: The cone-beam CT-enabled palliative treatment process is feasible and is ready for clinical implementation for the treatment of bone metastases using simple beam geometry, providing a streamlined one-step process toward palliative radiotherapy.

  15. Computerized assessment of motion-contaminated calcified plaques in cardiac multidetector CT

    SciTech Connect (OSTI)

    King, Martin; Giger, Maryellen L.; Suzuki, Kenji; Bardo, Dianna M. E.; Greenberg, Brent; Lan Li; Pan Xiaochuan [Department of Radiology, Committee on Medical Physics, University of Chicago, Chicago, Illinois 60637 (United States)

    2007-12-15

    An automated method for evaluating the image quality of calcified plaques with respect to motion artifacts in noncontrast-enhanced cardiac computed tomography (CT) images is introduced. This method involves using linear regression (LR) and artificial neural network (ANN) regression models for predicting two patient-specific, region-of-interest-specific, reconstruction-specific and temporal phase-specific image quality indices. The first is a plaque motion index, which is derived from the actual trajectory of the calcified plaque and is represented on a continuous scale. The second is an assessability index, which reflects the degree to which a calcified plaque is affected by motion artifacts, and is represented on an ordinal five-point scale. Two sets of assessability indices were provided independently by two radiologists experienced in evaluating cardiac CT images. Inputs for the regression models were selected from 12 features characterizing the dynamic, morphological, and intensity-based properties of the calcified plaques. Whereas LR-velocity (LR-V) used only a single feature (three-dimensional velocity), the LR-multiple (LR-M) and ANN regression models used the same subset of these 12 features selected through stepwise regression. The regression models were parameterized and evaluated using a database of simulated calcified plaque images from the dynamic NCAT phantom involving nine heart rate/multi-sector gating combinations and 40 cardiac phases covering two cardiac cycles. Six calcified plaques were used for the plaque motion indices and three calcified plaques were used for both sets of assessability indices. In one configuration, images from the second cardiac cycle were used for feature selection and regression model parameterization, whereas images from the first cardiac cycle were used for testing. With this configuration, repeated measures concordance correlation coefficients (CCCs) and associated 95% confidence intervals for the LR-V, LR-M, and ANN were 0.817 [0.785, 0.848], 0.894 [0.869, 0.916], and 0.917 [0.892, 0.936] for the plaque motion indices. For the two sets of assessability indices, CCC values for the ANN model were 0.843 [0.791, 0.877] and 0.793 [0.747, 0.828]. These two CCC values were statistically greater than the CCC value of 0.689 [0.648, 0.727], which was obtained by comparing the two sets of assessability indices with each other. These preliminary results suggest that the variabilities of assessability indices provided by regression models can lie within the variabilities of the indices assigned by independent observers. Thus, the potential exists for using regression models and assessability indices for determining optimal phases for cardiac CT image interpretation.

  16. Volumetric quantification of lung nodules in CT with iterative reconstruction (ASiR and MBIR)

    SciTech Connect (OSTI)

    Chen, Baiyu [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States)] [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 and Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States); Barnhart, Huiman [Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina 27705 (United States)] [Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina 27705 (United States); Richard, Samuel [Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 and Department of Radiology, Duke University, Durham, North Carolina 27705 (United States)] [Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 and Department of Radiology, Duke University, Durham, North Carolina 27705 (United States); Robins, Marthony [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States)] [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Colsher, James [Department of Radiology, Duke University, Durham, North Carolina 27705 (United States)] [Department of Radiology, Duke University, Durham, North Carolina 27705 (United States); Samei, Ehsan [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States) [Medical Physics Graduate Program, Duke University, Durham, North Carolina 27705 (United States); Carl E. Ravin Advanced Imaging Laboratories, Duke University, Durham, North Carolina 27705 (United States); Department of Radiology, Duke University, Durham, North Carolina 27705 (United States); Department of Physics, Department of Biomedical Engineering, and Department of Electronic and Computer Engineering, Duke University, Durham, North Carolina 27705 (United States)

    2013-11-15

    Purpose: Volume quantifications of lung nodules with multidetector computed tomography (CT) images provide useful information for monitoring nodule developments. The accuracy and precision of the volume quantification, however, can be impacted by imaging and reconstruction parameters. This study aimed to investigate the impact of iterative reconstruction algorithms on the accuracy and precision of volume quantification with dose and slice thickness as additional variables.Methods: Repeated CT images were acquired from an anthropomorphic chest phantom with synthetic nodules (9.5 and 4.8 mm) at six dose levels, and reconstructed with three reconstruction algorithms [filtered backprojection (FBP), adaptive statistical iterative reconstruction (ASiR), and model based iterative reconstruction (MBIR)] into three slice thicknesses. The nodule volumes were measured with two clinical software (A: Lung VCAR, B: iNtuition), and analyzed for accuracy and precision.Results: Precision was found to be generally comparable between FBP and iterative reconstruction with no statistically significant difference noted for different dose levels, slice thickness, and segmentation software. Accuracy was found to be more variable. For large nodules, the accuracy was significantly different between ASiR and FBP for all slice thicknesses with both software, and significantly different between MBIR and FBP for 0.625 mm slice thickness with Software A and for all slice thicknesses with Software B. For small nodules, the accuracy was more similar between FBP and iterative reconstruction, with the exception of ASIR vs FBP at 1.25 mm with Software A and MBIR vs FBP at 0.625 mm with Software A.Conclusions: The systematic difference between the accuracy of FBP and iterative reconstructions highlights the importance of extending current segmentation software to accommodate the image characteristics of iterative reconstructions. In addition, a calibration process may help reduce the dependency of accuracy on reconstruction algorithms, such that volumes quantified from scans of different reconstruction algorithms can be compared. The little difference found between the precision of FBP and iterative reconstructions could be a result of both iterative reconstruction's diminished noise reduction at the edge of the nodules as well as the loss of resolution at high noise levels with iterative reconstruction. The findings do not rule out potential advantage of IR that might be evident in a study that uses a larger number of nodules or repeated scans.

  17. SU-E-I-33: Initial Evaluation of Model-Based Iterative CT Reconstruction Using Standard Image Quality Phantoms

    SciTech Connect (OSTI)

    Gingold, E; Dave, J

    2014-06-01

    Purpose: The purpose of this study was to compare a new model-based iterative reconstruction with existing reconstruction methods (filtered backprojection and basic iterative reconstruction) using quantitative analysis of standard image quality phantom images. Methods: An ACR accreditation phantom (Gammex 464) and a CATPHAN600 phantom were scanned using 3 routine clinical acquisition protocols (adult axial brain, adult abdomen, and pediatric abdomen) on a Philips iCT system. Each scan was acquired using default conditions and 75%, 50% and 25% dose levels. Images were reconstructed using standard filtered backprojection (FBP), conventional iterative reconstruction (iDose4) and a prototype model-based iterative reconstruction (IMR). Phantom measurements included CT number accuracy, contrast to noise ratio (CNR), modulation transfer function (MTF), low contrast detectability (LCD), and noise power spectrum (NPS). Results: The choice of reconstruction method had no effect on CT number accuracy, or MTF (p<0.01). The CNR of a 6 HU contrast target was improved by 1–67% with iDose4 relative to FBP, while IMR improved CNR by 145–367% across all protocols and dose levels. Within each scan protocol, the CNR improvement from IMR vs FBP showed a general trend of greater improvement at lower dose levels. NPS magnitude was greatest for FBP and lowest for IMR. The NPS of the IMR reconstruction showed a pronounced decrease with increasing spatial frequency, consistent with the unusual noise texture seen in IMR images. Conclusion: Iterative Model Reconstruction reduces noise and improves contrast-to-noise ratio without sacrificing spatial resolution in CT phantom images. This offers the possibility of radiation dose reduction and improved low contrast detectability compared with filtered backprojection or conventional iterative reconstruction.

  18. SU-E-J-92: On-Line Cone Beam CT Based Planning for Emergency and Palliative Radiation Therapy

    SciTech Connect (OSTI)

    Held, M; Morin, O; Pouliot, J

    2014-06-01

    Purpose: To evaluate and develop the feasibility of on-line cone beam CT based planning for emergency and palliative radiotherapy treatments. Methods: Subsequent to phantom studies, a case library of 28 clinical megavoltage cone beam CT (MVCBCT) was built to assess dose-planning accuracies on MVCBCT for all anatomical sites. A simple emergency treatment plan was created on the MVCBCT and copied to its reference CT. The agreement between the dose distributions of each image pair was evaluated by the mean dose difference of the dose volume and the gamma index of the central 2D axial plane. An array of popular urgent and palliative cases was also evaluated for imaging component clearance and field-of-view. Results: The treatment cases were categorized into four groups (head and neck, thorax/spine, pelvis and extremities). Dose distributions for head and neck treatments were predicted accurately in all cases with a gamma index of >95% for 2% and 2 mm criteria. Thoracic spine treatments had a gamma index as low as 60% indicating a need for better uniformity correction and tissue density calibration. Small anatomy changes between CT and MVCBCT could contribute to local errors. Pelvis and sacral spine treatment cases had a gamma index between 90% and 98% for 3%/3 mm criteria. The limited FOV became an issue for large pelvis patients. Imaging clearance was difficult for cases where the tumor was positioned far off midline. Conclusion: The MVCBCT based dose planning and delivery approach is feasible in many treatment cases. Dose distributions for head and neck patients are unrestrictedly predictable. Some FOV restrictions apply to other treatment sites. Lung tissue is most challenging for accurate dose calculations given the current imaging filters and corrections. Additional clinical cases for extremities need to be included in the study to assess the full range of site-specific planning accuracies. This work is supported by Siemens.

  19. SU-E-J-190: Characterization of Radiation Induced CT Number Changes in Tumor and Normal Lung During Radiation Therapy for Lung Cancer

    SciTech Connect (OSTI)

    Yang, C; Liu, F; Tai, A; Gore, E; Johnstone, C; Li, X

    2014-06-01

    Purpose: To measure CT number (CTN) changes in tumor and normal lung as a function of radiation therapy (RT) dose during the course of RT delivery for lung cancer using daily IGRT CT images and single respiration phase CT images. Methods: 4D CT acquired during planning simulation and daily 3D CT acquired during daily IGRT for 10 lung cancer cases randomly selected in terms of age, caner type and stage, were analyzed using an in-house developed software tool. All patients were treated in 2 Gy fractions to primary tumors and involved nodal regions. Regions enclosed by a series of isodose surfaces in normal lung were delineated. The obtained contours along with target contours (GTVs) were populated to each singlephase planning CT and daily CT. CTN in term of Hounsfield Unit (HU) of each voxel in these delineated regions were collectively analyzed using histogram, mean, mode and linear correlation. Results: Respiration induced normal lung CTN change, as analyzed from single-phase planning CTs, ranged from 9 to 23 (±2) HU for the patients studied. Normal lung CTN change was as large as 50 (±12) HU over the entire treatment course, was dose and patient dependent and was measurable with dose changes as low as 1.5 Gy. For patients with obvious tumor volume regression, CTN within the GTV drops monotonically as much as 10 (±1) HU during the early fractions with a total dose of 20 Gy delivered. The GTV and CTN reductions are significantly correlated with correlation coefficient >0.95. Conclusion: Significant RT dose induced CTN changes in lung tissue and tumor region can be observed during even the early phase of RT delivery, and may potentially be used for early prediction of radiation response. Single respiration phase CT images have dramatically reduced statistical noise in ROIs, making daily dose response evaluation possible.

  20. CT-scan-monitored electrical-resistivity measurements show problems achieving homogeneous saturation

    SciTech Connect (OSTI)

    Sprunt, E.S.; Davis, R.M.; Muegge, E.L. (Mobil R and D Corp. (US)); Desai, K.P. (Saudi Aramco (SA))

    1991-06-01

    This paper reports on x-ray computerized tomography (CT) scans obtained during measurement of the electrical resistivity of core samples which revealed some problems in obtaining uniform saturation along the lengths of the samples. The electrical resistivity of core samples is measured as a function of water saturation to determine the saturation exponent used in electric-log interpretation. An assumption in such tests is that the water saturation is uniformly distributed. Failure of this assumption can result in errors in the determination of the saturation exponent. Three problems were identified in obtaining homogeneous water saturation in two samples of a Middle Eastern carbonate grainstone: a stationary front formed in one sample at 1-psi oil/brine capillary pressure, a moving front formed at oil/brine capillary pressure {le}4 psi in samples tested in fresh mixed-wettability and cleaned water-wet states, and the heterogeneous fluid distribution caused by a rapidly moving front did not dissipate when the capillary pressure was eliminated in the samples.

  1. Introduction of heat map to fidelity assessment of compressed CT images

    SciTech Connect (OSTI)

    Lee, Hyunna; Kim, Bohyoung; Seo, Jinwook; Park, Seongjin; Shin, Yeong-Gil; Kim, Kil Joong; Lee, Kyoung Ho

    2011-08-15

    Purpose: This study aimed to introduce heat map, a graphical data presentation method widely used in gene expression experiments, to the presentation and interpretation of image fidelity assessment data of compressed computed tomography (CT) images. Methods: The authors used actual assessment data that consisted of five radiologists' responses to 720 computed tomography images compressed using both Joint Photographic Experts Group 2000 (JPEG2000) 2D and JPEG2000 3D compressions. They additionally created data of two artificial radiologists, which were generated by partly modifying the data from two human radiologists. Results: For each compression, the entire data set, including the variations among radiologists and among images, could be compacted into a small color-coded grid matrix of the heat map. A difference heat map depicted the advantage of 3D compression over 2D compression. Dendrograms showing hierarchical agglomerative clustering results were added to the heat maps to illustrate the similarities in the data patterns among radiologists and among images. The dendrograms were used to identify two artificial radiologists as outliers, whose data were created by partly modifying the responses of two human radiologists. Conclusions: The heat map can illustrate a quick visual extract of the overall data as well as the entirety of large complex data in a compact space while visualizing the variations among observers and among images. The heat map with the dendrograms can be used to identify outliers or to classify observers and images based on the degree of similarity in the response patterns.

  2. CT14QED PDFs from Isolated Photon Production in Deep Inelastic Scattering

    E-Print Network [OSTI]

    Schmidt, Carl; Stump, Daniel; Yuan, C -P

    2015-01-01

    We describe the implementation of Quantum Electrodynamic (QED) evolution at Leading Order (LO) along with Quantum Chromodynamic (QCD) evolution at Next-to-Leading Order (NLO) in the CTEQ-TEA Global analysis package. The photon Parton Distribution Function (PDF) is described by a two-parameter ansatz, coming from radiation off the valence quarks, and based on the CT14 NLO PDFs. Setting the two parameters equal, allows us to completely specify the photon PDF in terms of the momentum fraction carried by the photon, $p_0^\\gamma$, at the initial scale $Q_0=1.295$ GeV. We obtain constraints on the photon PDF by comparing with ZEUS data~\\cite{Chekanov:2009dq} on the production of isolated photons in deep inelastic scattering, $ep\\rightarrow e\\gamma+X$. For this comparison we present a new perturbative calculation of the process that consistently combines the photon-initiated contribution with the quark-initiated contribution. Comparison with the data allows us to put a constraint at the 90% confidence level of $p_0^...

  3. Combined iterative reconstruction and image-domain decomposition for dual energy CT using total-variation regularization

    SciTech Connect (OSTI)

    Dong, Xue; Niu, Tianye; Zhu, Lei

    2014-05-15

    Purpose: Dual-energy CT (DECT) is being increasingly used for its capability of material decomposition and energy-selective imaging. A generic problem of DECT, however, is that the decomposition process is unstable in the sense that the relative magnitude of decomposed signals is reduced due to signal cancellation while the image noise is accumulating from the two CT images of independent scans. Direct image decomposition, therefore, leads to severe degradation of signal-to-noise ratio on the resultant images. Existing noise suppression techniques are typically implemented in DECT with the procedures of reconstruction and decomposition performed independently, which do not explore the statistical properties of decomposed images during the reconstruction for noise reduction. In this work, the authors propose an iterative approach that combines the reconstruction and the signal decomposition procedures to minimize the DECT image noise without noticeable loss of resolution. Methods: The proposed algorithm is formulated as an optimization problem, which balances the data fidelity and total variation of decomposed images in one framework, and the decomposition step is carried out iteratively together with reconstruction. The noise in the CT images from the proposed algorithm becomes well correlated even though the noise of the raw projections is independent on the two CT scans. Due to this feature, the proposed algorithm avoids noise accumulation during the decomposition process. The authors evaluate the method performance on noise suppression and spatial resolution using phantom studies and compare the algorithm with conventional denoising approaches as well as combined iterative reconstruction methods with different forms of regularization. Results: On the Catphan©600 phantom, the proposed method outperforms the existing denoising methods on preserving spatial resolution at the same level of noise suppression, i.e., a reduction of noise standard deviation by one order of magnitude. This improvement is mainly attributed to the high noise correlation in the CT images reconstructed by the proposed algorithm. Iterative reconstruction using different regularization, including quadratic orq-generalized Gaussian Markov random field regularization, achieves similar noise suppression from high noise correlation. However, the proposed TV regularization obtains a better edge preserving performance. Studies of electron density measurement also show that our method reduces the average estimation error from 9.5% to 7.1%. On the anthropomorphic head phantom, the proposed method suppresses the noise standard deviation of the decomposed images by a factor of ?14 without blurring the fine structures in the sinus area. Conclusions: The authors propose a practical method for DECT imaging reconstruction, which combines the image reconstruction and material decomposition into one optimization framework. Compared to the existing approaches, our method achieves a superior performance on DECT imaging with respect to decomposition accuracy, noise reduction, and spatial resolution.

  4. Experimental validation of a method characterizing bow tie filters in CT scanners using a real-time dose probe

    SciTech Connect (OSTI)

    McKenney, Sarah E.; Nosratieh, Anita; Gelskey, Dale; Yang Kai; Huang Shinying; Chen Lin; Boone, John M. [Department of Radiology, University of California, Davis Medical Center, Rm. 0505, ACC Ellison Bldg., 4860 Y St., Sacramento, California 95817 (United States) and Department of Biomedical Engineering, University of California, Davis, Rm. 2303, GBSF, 451 E. Health Science Dr., Davis, California 95616 (United States); Diagnostic Imaging Specialists Corporation (DISC), 163 St. Malo Street, St. Malo, Manitoba R0A 1T0 (Canada); Department of Radiology, University of California, Davis Medical Center, Rm. 0505, ACC Ellison Bldg., 4860 Y St., Sacramento, California 95817 (United States); Department of Radiology, University of California, Davis Medical Center, Rm. 0505, ACC Ellison Bldg., 4860 Y St., Sacramento, California 95817 (United States) and Department of Biomedical Engineering, University of California, Davis, Rm. 2303, GBSF, 451 E. Health Science Dr., Davis, California 95616 (United States)

    2011-03-15

    Purpose: Beam-shaping or ''bow tie'' (BT) filters are used to spatially modulate the x-ray beam in a CT scanner, but the conventional method of step-and-shoot measurement to characterize a beam's profile is tedious and time-consuming. The theory for characterization of bow tie relative attenuation (COBRA) method, which relies on a real-time dosimeter to address the issues of conventional measurement techniques, was previously demonstrated using computer simulations. In this study, the feasibility of the COBRA theory is further validated experimentally through the employment of a prototype real-time radiation meter and a known BT filter. Methods: The COBRA method consisted of four basic steps: (1) The probe was placed at the edge of a scanner's field of view; (2) a real-time signal train was collected as the scanner's gantry rotated with the x-ray beam on; (3) the signal train, without a BT filter, was modeled using peak values measured in the signal train of step 2; and (4) the relative attenuation of the BT filter was estimated from filtered and unfiltered data sets. The prototype probe was first verified to have an isotropic and linear response to incident x-rays. The COBRA method was then tested on a dedicated breast CT scanner with a custom-designed BT filter and compared to the conventional step-and-shoot characterization of the BT filter. Using basis decomposition of dual energy signal data, the thickness of the filter was estimated and compared to the BT filter's manufacturing specifications. The COBRA method was also demonstrated with a clinical whole body CT scanner using the body BT filter. The relative attenuation was calculated at four discrete x-ray tube potentials and used to estimate the thickness of the BT filter. Results: The prototype probe was found to have a linear and isotropic response to x-rays. The relative attenuation produced from the COBRA method fell within the error of the relative attenuation measured with the step-and-shoot method. The BT filter thickness estimates resulting from the dual energy scans on the breast CT system were equivalent to the manufacturing specifications. The clinical CT evaluation produced data conceptually similar to previous computer simulations and plausible relative attenuation profiles were observed. Conclusions: The COBRA method is a fast and accurate method for BT filter characterization, which requires a simple experimental setup in a clinical environment. Because of the ease of data acquisition, multienergy scans can be acquired which allow characterization of the BT filter thickness.

  5. Early prediction of tumor recurrence based on CT texture changes after stereotactic ablative radiotherapy (SABR) for lung cancer

    SciTech Connect (OSTI)

    Mattonen, Sarah A.; Palma, David A.; Department of Oncology, The University of Western Ontario, London, Ontario N6A 4L6; Division of Radiation Oncology, London Regional Cancer Program, London, Ontario N6A 4L6 ; Haasbeek, Cornelis J. A.; Senan, Suresh; Ward, Aaron D.

    2014-03-15

    Purpose: Benign computed tomography (CT) changes due to radiation induced lung injury (RILI) are common following stereotactic ablative radiotherapy (SABR) and can be difficult to differentiate from tumor recurrence. The authors measured the ability of CT image texture analysis, compared to more traditional measures of response, to predict eventual cancer recurrence based on CT images acquired within 5 months of treatment. Methods: A total of 24 lesions from 22 patients treated with SABR were selected for this study: 13 with moderate to severe benign RILI, and 11 with recurrence. Three-dimensional (3D) consolidative and ground-glass opacity (GGO) changes were manually delineated on all follow-up CT scans. Two size measures of the consolidation regions (longest axial diameter and 3D volume) and nine appearance features of the GGO were calculated: 2 first-order features [mean density and standard deviation of density (first-order texture)], and 7 second-order texture features [energy, entropy, correlation, inverse difference moment (IDM), inertia, cluster shade, and cluster prominence]. For comparison, the corresponding response evaluation criteria in solid tumors measures were also taken for the consolidation regions. Prediction accuracy was determined using the area under the receiver operating characteristic curve (AUC) and two-fold cross validation (CV). Results: For this analysis, 46 diagnostic CT scans scheduled for approximately 3 and 6 months post-treatment were binned based on their recorded scan dates into 2–5 month and 5–8 month follow-up time ranges. At 2–5 months post-treatment, first-order texture, energy, and entropy provided AUCs of 0.79–0.81 using a linear classifier. On two-fold CV, first-order texture yielded 73% accuracy versus 76%–77% with the second-order features. The size measures of the consolidative region, longest axial diameter and 3D volume, gave two-fold CV accuracies of 60% and 57%, and AUCs of 0.72 and 0.65, respectively. Conclusions: Texture measures of the GGO appearance following SABR demonstrated the ability to predict recurrence in individual patients within 5 months of SABR treatment. Appearance changes were also shown to be more accurately predictive of recurrence, as compared to size measures within the same time period. With further validation, these results could form the substrate for a clinically useful computer-aided diagnosis tool which could provide earlier salvage of patients with recurrence.

  6. Maddox, R. A., M. S. Gilmore, C. A. Doswell III, R. H. Johns, C. A. Crisp, D. W. Burgess, J. A. Hart, and S. F. Piltz, 2013: Meteorological analyses of the Tri-State tornado event of March 1925. Electronic J.

    E-Print Network [OSTI]

    Doswell III, Charles A.

    . Hart, and S. F. Piltz, 2013: Meteorological analyses of the Tri-State tornado event of March 1925. CRISP,@ DONALD W. BURGESS,@ JOHN A. HART,~ AND STEVEN F. PILTZ> *Tucson, Arizona + Department

  7. SU-E-QI-08: Fourier Properties of Cone Beam CT Projection

    SciTech Connect (OSTI)

    Bai, T; Yan, H; Jia, X; Jiang, Steve B.; Mou, X

    2014-06-15

    Purpose: To explore the Fourier properties of cone beam CT (CBCT) projections and apply the property to directly estimate noise level of CBCT projections without any prior information. Methods: By utilizing the property of Bessel function, we derivate the Fourier properties of the CBCT projections for an arbitrary point object. It is found that there exists a double-wedge shaped region in the Fourier space where the intensity is approximately zero. We further derivate the Fourier properties of independent noise added to CBCT projections. The expectation of the square of the module in any point of the Fourier space is constant and the value approximately equals to noise energy. We further validate the theory in numerical simulations for both a delta function object and a NCAT phantom with different levels of noise added. Results: Our simulation confirmed the existence of the double-wedge shaped region in Fourier domain for the x-ray projection image. The boundary locations of this region agree well with theoretical predictions. In the experiments of estimating noise level, the mean relative error between the theory estimation and the ground truth values is 2.697%. Conclusion: A novel theory on the Fourier properties of CBCT projections has been discovered. Accurate noise level estimation can be achieved by applying this theory directly to the measured CBCT projections. This work was supported in part by NIH(1R01CA154747-01), NSFC((No. 61172163), Research Fund for the Doctoral Program of Higher Education of China (No. 20110201110011) and China Scholarship Council.

  8. MicroCT-Based Skeletal Models for Use in Tomographic Voxel Phantoms for Radiological Protection

    SciTech Connect (OSTI)

    Wesley Bolch

    2010-03-30

    ABSTRACT The University of Florida (UF) proposes to develop two high-resolution image-based skeletal dosimetry models for direct use by ICRP Committee 2’s Task Group on Dose Calculation in their forthcoming Reference Voxel Male (RVM) and Reference Voxel Female (RVF) whole-body dosimetry phantoms. These two phantoms are CT-based, and thus do not have the image resolution to delineate and perform radiation transport modeling of the individual marrow cavities and bone trabeculae throughout their skeletal structures. Furthermore, new and innovative 3D microimaging techniques will now be required for the skeletal tissues following Committee 2’s revision of the target tissues of relevance for radiogenic bone cancer induction. This target tissue had been defined in ICRP Publication 30 as a 10-?m cell layer on all bone surfaces of trabecular and cortical bone. The revised target tissue is now a 50-?m layer within the marrow cavities of trabecular bone only and is exclusive of the marrow adipocytes. Clearly, this new definition requires the use of 3D microimages of the trabecular architecture not available from past 2D optical studies of the adult skeleton. With our recent acquisition of two relatively young cadavers (males of age 18-years and 40-years), we will develop a series of reference skeletal models that can be directly applied to (1) the new ICRP reference voxel man and female phantoms developed for the ICRP, and (2) pediatric phantoms developed to target the ICRP reference children. Dosimetry data to be developed will include absorbed fractions for internal beta and alpha-particle sources, as well as photon and neutron fluence-to-dose response functions for direct use in external dosimetry studies of the ICRP reference workers and members of the general public

  9. Noise suppression in reconstruction of low-Z target megavoltage cone-beam CT images

    SciTech Connect (OSTI)

    Wang Jing; Robar, James; Guan Huaiqun

    2012-08-15

    Purpose: To improve the image contrast-to-noise (CNR) ratio for low-Z target megavoltage cone-beam CT (MV CBCT) using a statistical projection noise suppression algorithm based on the penalized weighted least-squares (PWLS) criterion. Methods: Projection images of a contrast phantom, a CatPhan{sup Registered-Sign} 600 phantom and a head phantom were acquired by a Varian 2100EX LINAC with a low-Z (Al) target and low energy x-ray beam (2.5 MeV) at a low-dose level and at a high-dose level. The projections were then processed by minimizing the PWLS objective function. The weighted least square (WLS) term models the noise of measured projection and the penalty term enforces the smoothing constraints of the projection image. The variance of projection data was chosen as the weight for the PWLS objective function and it determined the contribution of each measurement. An anisotropic quadratic form penalty that incorporates the gradient information of projection image was used to preserve edges during noise reduction. Low-Z target MV CBCT images were reconstructed by the FDK algorithm after each projection was processed by the PWLS smoothing. Results: Noise in low-Z target MV CBCT images were greatly suppressed after the PWLS projection smoothing, without noticeable sacrifice of the spatial resolution. Depending on the choice of smoothing parameter, the CNR of selected regions of interest in the PWLS processed low-dose low-Z target MV CBCT image can be higher than the corresponding high-dose image.Conclusion: The CNR of low-Z target MV CBCT images was substantially improved by using PWLS projection smoothing. The PWLS projection smoothing algorithm allows the reconstruction of high contrast low-Z target MV CBCT image with a total dose of as low as 2.3 cGy.

  10. A robust and efficient approach to detect 3D rectal tubes from CT colonography

    SciTech Connect (OSTI)

    Yang Xiaoyun; Slabaugh, Greg [Medicsight PLC, Kensington Centre, 66 Hammersmith Road, London (United Kingdom)

    2011-11-15

    Purpose: The rectal tube (RT) is a common source of false positives (FPs) in computer-aided detection (CAD) systems for CT colonography. A robust and efficient detection of RT can improve CAD performance by eliminating such ''obvious'' FPs and increase radiologists' confidence in CAD. Methods: In this paper, we present a novel and robust bottom-up approach to detect the RT. Probabilistic models, trained using kernel density estimation on simple low-level features, are employed to rank and select the most likely RT tube candidate on each axial slice. Then, a shape model, robustly estimated using random sample consensus (RANSAC), infers the global RT path from the selected local detections. Subimages around the RT path are projected into a subspace formed from training subimages of the RT. A quadratic discriminant analysis (QDA) provides a classification of a subimage as RT or non-RT based on the projection. Finally, a bottom-top clustering method is proposed to merge the classification predictions together to locate the tip position of the RT. Results: Our method is validated using a diverse database, including data from five hospitals. On a testing data with 21 patients (42 volumes), 99.5% of annotated RT paths have been successfully detected. Evaluated with CAD, 98.4% of FPs caused by the RT have been detected and removed without any loss of sensitivity. Conclusions: The proposed method demonstrates a high detection rate of the RT path, and when tested in a CAD system, reduces FPs caused by the RT without the loss of sensitivity.

  11. Asymmetrical-fan tranmission CT on SPECT to derive {mu}-maps for attenuation correction

    SciTech Connect (OSTI)

    Loncaric, S.; Huang, G.; Ni, B. [Rush-Presbyterian-St. Luke`s Medical Center, Chicago, IL (United States)] [and others

    1994-05-01

    For proper attenuation correction of SPECT images, an appropriate {mu}-map properly registered with each imaging slices is needed. Among the many techniques for {mu}-map derivation, simultaneous or sequential fan-beam transmission CT (TCT), on the same SPECT system with the same acquisition settings, have advantages of being practical while ensuring registration. However, the problems are: (1) limited FOV for thoracic imaging, projection would be truncated with a typical size detector, (2) lack of room for placing the transmission source in many SPECT systems. We have developed a new sampling scheme to solve the problems mentioned above. This scheme uses an asymmetrical-fan geometry (AFG), which samples only half of the field, the other half would be sampled after an 180{degrees} detector rotation. This technique completes the minimum sampling requirement in a 360{degrees} detector rotation and yields a relatively large FOV defined by the outside edge of the sampling fan. We have confirmed the feasibility of the AFG sampling on a 3-head SPECT system to provide a large FOV for TCT of most patient. The TCT sampling scheme is achieved with an asymmetrical-fan collimator. We have developed the required new reconstruction algorithms and derived excellent reconstructed images of phantoms and human subjects. We propose to have this technique implemented in a short and fast transmission scan in a multi-head SPECT system, after emission imaging, because the detectors have to be pulled out to make room for the transmission source. The imaging field can even exceed the full field size of the detector. MS would be possible when an obtuse sampling fan is formed by shifting the source outward further, provided the central FOV is properly covered with a supplementary sampling scheme, e.g., using another TCT with a fan-beam collimator on another one of the detectors.

  12. Establishing a process of irradiating small animal brain using a CyberKnife and a microCT scanner

    SciTech Connect (OSTI)

    Kim, Haksoo; Welford, Scott; Fabien, Jeffrey; Zheng, Yiran; Yuan, Jake; Brindle, James; Yao, Min; Lo, Simon; Wessels, Barry; Machtay, Mitchell; Sohn, Jason W.; Sloan, Andrew

    2014-02-15

    Purpose: Establish and validate a process of accurately irradiating small animals using the CyberKnife G4 System (version 8.5) with treatment plans designed to irradiate a hemisphere of a mouse brain based on microCT scanner images. Methods: These experiments consisted of four parts: (1) building a mouse phantom for intensity modulated radiotherapy (IMRT) quality assurance (QA), (2) proving usability of a microCT for treatment planning, (3) fabricating a small animal positioning system for use with the CyberKnife's image guided radiotherapy (IGRT) system, and (4)in vivo verification of targeting accuracy. A set of solid water mouse phantoms was designed and fabricated, with radiochromic films (RCF) positioned in selected planes to measure delivered doses. After down-sampling for treatment planning compatibility, a CT image set of a phantom was imported into the CyberKnife treatment planning system—MultiPlan (ver. 3.5.2). A 0.5 cm diameter sphere was contoured within the phantom to represent a hemispherical section of a mouse brain. A nude mouse was scanned in an alpha cradle using a microCT scanner (cone-beam, 157 × 149 pixels slices, 0.2 mm longitudinal slice thickness). Based on the results of our positional accuracy study, a planning treatment volume (PTV) was created. A stereotactic body mold of the mouse was “printed” using a 3D printer laying UV curable acrylic plastic. Printer instructions were based on exported contours of the mouse's skin. Positional reproducibility in the mold was checked by measuring ten CT scans. To verify accurate dose delivery in vivo, six mice were irradiated in the mold with a 4 mm target contour and a 2 mm PTV margin to 3 Gy and sacrificed within 20 min to avoid DNA repair. The brain was sliced and stained for analysis. Results: For the IMRT QA using a set of phantoms, the planned dose (6 Gy to the calculation point) was compared to the delivered dose measured via film and analyzed using Gamma analysis (3% and 3 mm). A passing rate of 99% was measured in areas of above 40% of the prescription dose. The final inverse treatment plan was comprised of 43 beams ranging from 5 to 12.5 mm in diameter (2.5 mm size increments are available up to 15 mm in diameter collimation). Using the Xsight Spine Tracking module, the CyberKnife system could not reliably identify and track the tiny mouse spine; however, the CyberKnife system could identify and track the fiducial markers on the 3D mold.In vivo positional accuracy analysis using the 3D mold generated a mean error of 1.41 mm ± 0.73 mm when fiducial markers were used for position tracking. Analysis of the dissected brain confirmed the ability to target the correct brain volume. Conclusions: With the use of a stereotactic body mold with fiducial markers, microCT imaging, and resolution down-sampling, the CyberKnife system can successfully perform small-animal radiotherapy studies.

  13. SU-E-I-45: Reconstruction of CT Images From Sparsely-Sampled Data Using the Logarithmic Barrier Method

    SciTech Connect (OSTI)

    Xu, H

    2014-06-01

    Purpose: To develop and investigate whether the logarithmic barrier (LB) method can result in high-quality reconstructed CT images using sparsely-sampled noisy projection data Methods: The objective function is typically formulated as the sum of the total variation (TV) and a data fidelity (DF) term with a parameter ? that governs the relative weight between them. Finding the optimized value of ? is a critical step for this approach to give satisfactory results. The proposed LB method avoid using ? by constructing the objective function as the sum of the TV and a log function whose augment is the DF term. Newton's method was used to solve the optimization problem. The algorithm was coded in MatLab2013b. Both Shepp-Logan phantom and a patient lung CT image were used for demonstration of the algorithm. Measured data were simulated by calculating the projection data using radon transform. A Poisson noise model was used to account for the simulated detector noise. The iteration stopped when the difference of the current TV and the previous one was less than 1%. Results: Shepp-Logan phantom reconstruction study shows that filtered back-projection (FBP) gives high streak artifacts for 30 and 40 projections. Although visually the streak artifacts are less pronounced for 64 and 90 projections in FBP, the 1D pixel profiles indicate that FBP gives noisier reconstructed pixel values than LB does. A lung image reconstruction is presented. It shows that use of 64 projections gives satisfactory reconstructed image quality with regard to noise suppression and sharp edge preservation. Conclusion: This study demonstrates that the logarithmic barrier method can be used to reconstruct CT images from sparsely-amped data. The number of projections around 64 gives a balance between the over-smoothing of the sharp demarcation and noise suppression. Future study may extend to CBCT reconstruction and improvement on computation speed.

  14. SU-E-I-60: The Correct Selection of Pitch and Rotation Time for Optimal CT Scanning : The Big Misconception

    SciTech Connect (OSTI)

    Ranallo, F; Szczykutowicz, T

    2014-06-01

    Purpose: To provide correct guidance in the proper selection of pitch and rotation time for optimal CT imaging with multi-slice scanners. Methods: There exists a widespread misconception concerning the role of pitch in patient dose with modern multi-slice scanners, particularly with the use of mA modulation techniques. We investigated the relationship of pitch and rotation time to image quality, dose, and scan duration, with CT scanners from different manufacturers in a way that clarifies this misconception. This source of this misconception may concern the role of pitch in single slice CT scanners. Results: We found that the image noise and dose are generally independent of the selected effective mAs (mA*time/ pitch) with manual mA technique settings and are generally independent of the selected pitch and /or rotation time with automatic mA modulation techniques. However we did find that on certain scanners the use of a pitch just above 0.5 provided images of equal image noise at a lower dose compared to the use of a pitch just below 1.0. Conclusion: The misconception that the use of a lower pitch over-irradiates patients by wasting dose is clearly false. The use of a lower pitch provides images of equal or better image quality at the same patient dose, whether using manual mA or automatic mA modulation techniques. By decreasing the pitch and the rotation times by equal amounts, both helical and patient motion artifacts can be reduced without affecting the exam time. The use of lower helical pitch also allows better scanning of larger patients by allowing a greater scan effective mAs, if the exam time can be extended. The one caution with the use of low pitch is not related to patient dose, but to the length of the scan time if the rotation time is not set short enough. Partial Research funding from GE HealthCare.

  15. A Fully Automated Method for CT-on-Rails-Guided Online Adaptive Planning for Prostate Cancer Intensity Modulated Radiation Therapy

    SciTech Connect (OSTI)

    Li, Xiaoqiang; Quan, Enzhuo M.; Li, Yupeng; Pan, Xiaoning; Zhou, Yin; Wang, Xiaochun; Du, Weiliang; Kudchadker, Rajat J.; Johnson, Jennifer L.; Kuban, Deborah A.; Lee, Andrew K.; Zhang, Xiaodong

    2013-08-01

    Purpose: This study was designed to validate a fully automated adaptive planning (AAP) method which integrates automated recontouring and automated replanning to account for interfractional anatomical changes in prostate cancer patients receiving adaptive intensity modulated radiation therapy (IMRT) based on daily repeated computed tomography (CT)-on-rails images. Methods and Materials: Nine prostate cancer patients treated at our institution were randomly selected. For the AAP method, contours on each repeat CT image were automatically generated by mapping the contours from the simulation CT image using deformable image registration. An in-house automated planning tool incorporated into the Pinnacle treatment planning system was used to generate the original and the adapted IMRT plans. The cumulative dose–volume histograms (DVHs) of the target and critical structures were calculated based on the manual contours for all plans and compared with those of plans generated by the conventional method, that is, shifting the isocenters by aligning the images based on the center of the volume (COV) of prostate (prostate COV-aligned). Results: The target coverage from our AAP method for every patient was acceptable, while 1 of the 9 patients showed target underdosing from prostate COV-aligned plans. The normalized volume receiving at least 70 Gy (V{sub 70}), and the mean dose of the rectum and bladder were reduced by 8.9%, 6.4 Gy and 4.3%, 5.3 Gy, respectively, for the AAP method compared with the values obtained from prostate COV-aligned plans. Conclusions: The AAP method, which is fully automated, is effective for online replanning to compensate for target dose deficits and critical organ overdosing caused by interfractional anatomical changes in prostate cancer.

  16. SU-E-I-59: Image Quality and Dose Measurement for Partial Cone-Beam CT

    SciTech Connect (OSTI)

    Abouei, E; Ford, N

    2014-06-01

    Purpose: To characterize performance of cone beam CT (CBCT) used in dentistry investigating quantitatively the image quality and radiation dose during dental CBCT over different settings for partial rotation of the x-ray tube. Methods: Image quality and dose measurements were done on a variable field of view (FOV) dental CBCT (Carestream 9300). X-ray parameters for clinical settings were adjustable for 2–10 mA, 60–90 kVp, and two optional voxel size values, but time was fixed for each FOV. Image quality was assessed by scanning cylindrical poly-methyl methacrylate (PMMA) image quality phantom (SEDENTEXCT IQ), and then the images were analyzed using ImageJ to calculate image quality parameters such as noise, uniformity, and contrast to noise ratio (CNR). A protocol proposed by SEDENTEXCT, dose index 1 (DI1), was applied to dose measurements obtained using a thimble ionization chamber and cylindrical PMMA dose index phantom (SEDENTEXCT DI). Dose distributions were obtained using Gafchromic film. The phantoms were positioned in the FOV to imitate a clinical positioning. Results: The image noise was 6–12.5% which, when normalized to the difference of mean voxel value of PMMA and air, was comparable between different FOVs. Uniformity was 93.5ß 99.7% across the images. CNR was 1.7–4.2 and 6.3–14.3 for LDPE and Aluminum, respectively. Dose distributions were symmetric about the rotation angle's bisector. For large and medium FOVs at 4 mA and 80–90 kVp, DI1 values were in the range of 1.26–3.23 mGy. DI1 values were between 1.01–1.93 mGy for small FOV (5×5 cm{sup 2}) at 4–5 mA and 75–84 kVp. Conclusion: Noise decreased by increasing kVp, and the CNR increased for each FOV. When FOV size increased, image noise increased and CNR decreased. DI1 values were increased by increasing tube current (mA), tube voltage (kVp), and/or FOV. Funding for this project from NSERC Discovery grant, UBC Faculty of Dentistry Research Equipment Grant and UBC Faculty of Dentistry S. Wah Leung Endowment Fund.

  17. A prototype fan-beam optical CT scanner for 3D dosimetry

    SciTech Connect (OSTI)

    Campbell, Warren G.; Rudko, D. A.; Braam, Nicolas A.; Jirasek, Andrew [University of Victoria, Victoria, British Columbia V8P 5C2 (Canada); Wells, Derek M. [British Columbia Cancer Agency, Vancouver Island Centre, Victoria, British Columbia V8R 6V5 (Canada)

    2013-06-15

    Purpose: The objective of this work is to introduce a prototype fan-beam optical computed tomography scanner for three-dimensional (3D) radiation dosimetry. Methods: Two techniques of fan-beam creation were evaluated: a helium-neon laser (HeNe, {lambda} = 543 nm) with line-generating lens, and a laser diode module (LDM, {lambda} = 635 nm) with line-creating head module. Two physical collimator designs were assessed: a single-slot collimator and a multihole collimator. Optimal collimator depth was determined by observing the signal of a single photodiode with varying collimator depths. A method of extending the dynamic range of the system is presented. Two sample types were used for evaluations: nondosimetric absorbent solutions and irradiated polymer gel dosimeters, each housed in 1 liter cylindrical plastic flasks. Imaging protocol investigations were performed to address ring artefacts and image noise. Two image artefact removal techniques were performed in sinogram space. Collimator efficacy was evaluated by imaging highly opaque samples of scatter-based and absorption-based solutions. A noise-based flask registration technique was developed. Two protocols for gel manufacture were examined. Results: The LDM proved advantageous over the HeNe laser due to its reduced noise. Also, the LDM uses a wavelength more suitable for the PRESAGE{sup TM} dosimeter. Collimator depth of 1.5 cm was found to be an optimal balance between scatter rejection, signal strength, and manufacture ease. The multihole collimator is capable of maintaining accurate scatter-rejection to high levels of opacity with scatter-based solutions (T < 0.015%). Imaging protocol investigations support the need for preirradiation and postirradiation scanning to reduce reflection-based ring artefacts and to accommodate flask imperfections and gel inhomogeneities. Artefact removal techniques in sinogram space eliminate streaking artefacts and reduce ring artefacts of up to {approx}40% in magnitude. The flask registration technique was shown to achieve submillimetre and subdegree placement accuracy. Dosimetry protocol investigations emphasize the need to allow gel dosimeters to cool gradually and to be scanned while at room temperature. Preliminary tests show that considerable noise reduction can be achieved with sinogram filtering and by binning image pixels into more clinically relevant grid sizes. Conclusions: This paper describes a new optical CT scanner for 3D radiation dosimetry. Tests demonstrate that it is capable of imaging both absorption-based and scatter-based samples of high opacities. Imaging protocol and gel dosimeter manufacture techniques have been adapted to produce optimal reconstruction results. These optimal results will require suitable filtering and binning techniques for noise reduction purposes.

  18. Sci—Fri AM: Mountain — 02: A comparison of dose reduction methods on image quality for cone beam CT

    SciTech Connect (OSTI)

    Webb, R; Buckley, LA

    2014-08-15

    Modern radiotherapy uses highly conformai dose distributions and therefore relies on daily image guidance for accurate patient positioning. Kilovoltage cone beam CT is one technique that is routinely used for patient set-up and results in a high dose to the patient relative to planar imaging techniques. This study uses an Elekta Synergy linac equipped with XVI cone beam CT to investigate the impact of various imaging parameters on dose and image quality. Dose and image quality are assessed as functions of x-ray tube voltage, tube current and the number of projections in the scan. In each case, the dose measurements confirm that as each parameter increases the dose increases. The assessment of high contrast resolution shows little dependence on changes to the image technique. However, low contrast visibility suggests a trade off between dose and image quality. Particularly for changes in tube potential, the dose increases much faster as a function of voltage than the corresponding increase in low contrast image quality. This suggests using moderate values of the peak tube voltage (100 – 120 kVp) since higher values result in significant dose increases with little gain in image quality. Measurements also indicate that increasing tube current achieves the greatest degree of improvement in the low contrast visibility. The results of this study highlight the need to establish careful imaging protocols to limit dose to the patient and to limit changes to the imaging parameters to those cases where there is a clear clinical requirement for improved image quality.

  19. Radiofrequency Ablation of Non-Small-Cell Carcinoma of the Lung Under Real-Time FDG PET CT Guidance

    SciTech Connect (OSTI)

    Schoellnast, Helmut; Larson, Steven M. [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States); Nehmeh, Sadek A. [Memorial Sloan-Kettering Cancer Center, Department of Medical Physics (United States); Carrasquillo, Jorge A.; Thornton, Raymond H.; Solomon, Stephen B., E-mail: solomons@mskcc.org [Memorial Sloan-Kettering Cancer Center, Department of Radiology (United States)

    2011-02-15

    Radiofrequency ablation (RFA) is a well-established method in treatment of patients with lung carcinomas who are not candidates for surgical resection. Usually computed tomographic (CT) guidance is used for the procedure, thus enabling needle placement and permitting evaluation of complications such as pneumothorax and bleeding. {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET) is generally used for tumor activity assessment and is therefore useful in follow-up after tumor treatment. A method that provides real-time image-based monitoring of RFA to ensure complete tumor ablation would be a valuable tool. In this report, we describe the behavior of preinjected FDG during PET CT-guided RFA of a non-small-cell lung carcinoma and discuss the value of FDG as a tool to provide intraprocedure monitor ablation. The size and the form of the activity changed during ablation. Ablation led to increase of the size and blurring and irregularity of the contour compared to pretreatment imaging. The maximal standardized uptake value decreased only slightly during the procedure. Therefore, before RFA, FDG PET can guide initial needle placement, but it does not serve as a monitoring tool to evaluate residual viable tissue during the procedure.

  20. SU-E-I-82: Improving CT Image Quality for Radiation Therapy Using Iterative Reconstruction Algorithms and Slightly Increasing Imaging Doses

    SciTech Connect (OSTI)

    Noid, G; Chen, G; Tai, A; Li, X

    2014-06-01

    Purpose: Iterative reconstruction (IR) algorithms are developed to improve CT image quality (IQ) by reducing noise without diminishing spatial resolution or contrast. For CT in radiation therapy (RT), slightly increasing imaging dose to improve IQ may be justified if it can substantially enhance structure delineation. The purpose of this study is to investigate and to quantify the IQ enhancement as a result of increasing imaging doses and using IR algorithms. Methods: CT images were acquired for phantoms, built to evaluate IQ metrics including spatial resolution, contrast and noise, with a variety of imaging protocols using a CT scanner (Definition AS Open, Siemens) installed inside a Linac room. Representative patients were scanned once the protocols were optimized. Both phantom and patient scans were reconstructed using the Sinogram Affirmed Iterative Reconstruction (SAFIRE) and the Filtered Back Projection (FBP) methods. IQ metrics of the obtained CTs were compared. Results: IR techniques are demonstrated to preserve spatial resolution as measured by the point spread function and reduce noise in comparison to traditional FBP. Driven by the reduction in noise, the contrast to noise ratio is doubled by adopting the highest SAFIRE strength. As expected, increasing imaging dose reduces noise for both SAFIRE and FBP reconstructions. The contrast to noise increases from 3 to 5 by increasing the dose by a factor of 4. Similar IQ improvement was observed on the CTs for selected patients with pancreas and prostrate cancers. Conclusion: The IR techniques produce a measurable enhancement to CT IQ by reducing the noise. Increasing imaging dose further reduces noise independent of the IR techniques. The improved CT enables more accurate delineation of tumors and/or organs at risk during RT planning and delivery guidance.

  1. SU-E-I-57: Evaluation and Optimization of Effective-Dose Using Different Beam-Hardening Filters in Clinical Pediatric Shunt CT Protocol

    SciTech Connect (OSTI)

    Gill, K; Aldoohan, S; Collier, J

    2014-06-01

    Purpose: Study image optimization and radiation dose reduction in pediatric shunt CT scanning protocol through the use of different beam-hardening filters Methods: A 64-slice CT scanner at OU Childrens Hospital has been used to evaluate CT image contrast-to-noise ratio (CNR) and measure effective-doses based on the concept of CT dose index (CTDIvol) using the pediatric head shunt scanning protocol. The routine axial pediatric head shunt scanning protocol that has been optimized for the intrinsic x-ray tube filter has been used to evaluate CNR by acquiring images using the ACR approved CT-phantom and radiation dose CTphantom, which was used to measure CTDIvol. These results were set as reference points to study and evaluate the effects of adding different filtering materials (i.e. Tungsten, Tantalum, Titanium, Nickel and Copper filters) to the existing filter on image quality and radiation dose. To ensure optimal image quality, the scanner routine air calibration was run for each added filter. The image CNR was evaluated for different kVps and wide range of mAs values using above mentioned beam-hardening filters. These scanning protocols were run under axial as well as under helical techniques. The CTDIvol and the effective-dose were measured and calculated for all scanning protocols and added filtration, including the intrinsic x-ray tube filter. Results: Beam-hardening filter shapes energy spectrum, which reduces the dose by 27%. No noticeable changes in image low contrast detectability Conclusion: Effective-dose is very much dependent on the CTDIVol, which is further very much dependent on beam-hardening filters. Substantial reduction in effective-dose is realized using beam-hardening filters as compare to the intrinsic filter. This phantom study showed that significant radiation dose reduction could be achieved in CT pediatric shunt scanning protocols without compromising in diagnostic value of image quality.

  2. Noise variance analysis using a flat panel x-ray detector: A method for additive noise assessment with application to breast CT applications

    SciTech Connect (OSTI)

    Yang Kai; Huang, Shih-Ying; Packard, Nathan J.; Boone, John M. [Department of Radiology, University of California, Davis Medical Center, 4860 Y Street, Suite 3100 Ellison Building, Sacramento, California 95817 (United States); Department of Radiology, University of California, Davis Medical Center, 4860 Y Street, Suite 3100 Ellison Building, Sacramento, California 95817 (United States) and Department of Biomedical Engineering, University of California, Davis, Davis, California, 95616 (United States)

    2010-07-15

    Purpose: A simplified linear model approach was proposed to accurately model the response of a flat panel detector used for breast CT (bCT). Methods: Individual detector pixel mean and variance were measured from bCT projection images acquired both in air and with a polyethylene cylinder, with the detector operating in both fixed low gain and dynamic gain mode. Once the coefficients of the linear model are determined, the fractional additive noise can be used as a quantitative metric to evaluate the system's efficiency in utilizing x-ray photons, including the performance of different gain modes of the detector. Results: Fractional additive noise increases as the object thickness increases or as the radiation dose to the detector decreases. For bCT scan techniques on the UC Davis prototype scanner (80 kVp, 500 views total, 30 frames/s), in the low gain mode, additive noise contributes 21% of the total pixel noise variance for a 10 cm object and 44% for a 17 cm object. With the dynamic gain mode, additive noise only represents approximately 2.6% of the total pixel noise variance for a 10 cm object and 7.3% for a 17 cm object. Conclusions: The existence of the signal-independent additive noise is the primary cause for a quadratic relationship between bCT noise variance and the inverse of radiation dose at the detector. With the knowledge of the additive noise contribution to experimentally acquired images, system modifications can be made to reduce the impact of additive noise and improve the quantum noise efficiency of the bCT system.

  3. SU-D-9A-04: Brain PET/CT Imaging On a Scanner with a Large Axial Field-Of-View

    SciTech Connect (OSTI)

    Park, M; Gerbaudo, V; Hamberg, L; Seaver, K; Kijewski, M

    2014-06-01

    Purpose: Large axial field-of-view (FOV) PET/CT scanners are valued for high sensitivity. Brain PET image quality may depend on the head position within the FOV. We investigated the precision of activity estimation for brain PET imaging when the brain was positioned at the end (END) and in the middle (CEN) of the FOV. The additional CT dose for the CEN position was recorded. Methods: An image quality (Jaszczak) phantom and a striatal phantom were filled with F-18 and positioned in END and CEN locations. For each phantom and each location, we acquired a ?1-hr listmode PET, rebinned the data into 10 frames with equal number of coincidence events, and reconstructed each frame using an iterative algorithm. For the striatal phantom, END and CEN were compared by drawing on each image three regions of interest (ROI) in axially separated uniform areas. The standard deviation of the activity estimation within each ROI was averaged over the 10 images. The coefficient of variation (CV) for activity estimation was calculated at each position. Image quality was assessed by inspecting the resolution bar pattern in the Jaszczak phantom at two different head positions. Results: The CV was the lowest for ROIs near the center of the FOV. For slices near the end, not only was the CV highest, but also the resolution pattern was degraded. CTDIvol summarized in the dose report indicated that the CT dose was ? 10% higher for CEN as compared to END position. Conclusion: Positioning the brain in the middle of the FOV in a large FOV PET/CT scanner allows more precise measurement of tracer uptake and better image quality at the cost of increased CT dose. For the end location longer scan times may minimize image quality degradation without any additional CT dose.

  4. SU-E-J-219: Quantitative Evaluation of Motion Effects On Accuracy of Image-Guided Radiotherapy with Fiducial Markers Using CT Imaging

    SciTech Connect (OSTI)

    Ali, I; Oyewale, S; Ahmad, S; Algan, O [University of Oklahoma Health Sciences, Oklahoma City, OK (United States); Alsbou, N [Department of Electrical and Computer Engineering, Ada, OH (United States)

    2014-06-01

    Purpose: To investigate quantitatively patient motion effects on the localization accuracy of image-guided radiation with fiducial markers using axial CT (ACT), helical CT (HCT) and cone-beam CT (CBCT) using modeling and experimental phantom studies. Methods: Markers with different lengths (2.5 mm, 5 mm, 10 mm, and 20 mm) were inserted in a mobile thorax phantom which was imaged using ACT, HCT and CBCT. The phantom moved with sinusoidal motion with amplitudes ranging 0–20 mm and a frequency of 15 cycles-per-minute. Three parameters that include: apparent marker lengths, center position and distance between the centers of the markers were measured in the different CT images of the mobile phantom. A motion mathematical model was derived to predict the variations in the previous three parameters and their dependence on the motion in the different imaging modalities. Results: In CBCT, the measured marker lengths increased linearly with increase in motion amplitude. For example, the apparent length of the 10 mm marker was about 20 mm when phantom moved with amplitude of 5 mm. Although the markers have elongated, the center position and the distance between markers remained at the same position for different motion amplitudes in CBCT. These parameters were not affected by motion frequency and phase in CBCT. In HCT and ACT, the measured marker length, center and distance between markers varied irregularly with motion parameters. The apparent lengths of the markers varied with inverse of the phantom velocity which depends on motion frequency and phase. Similarly the center position and distance between markers varied inversely with phantom speed. Conclusion: Motion may lead to variations in maker length, center position and distance between markers using CT imaging. These effects should be considered in patient setup using image-guided radiation therapy based on fiducial markers matching using 2D-radiographs or volumetric CT imaging.

  5. $\\cos 2 ?$ asymmetries in unpolarized semi-inclusive DIS

    E-Print Network [OSTI]

    Bing Zhang; Zhun Lu; Bo-Qiang Ma; Ivan Schmidt

    2008-08-22

    We use the Boer-Mulders functions parameterized from unpolarized $p+D$ Drell-Yan data by the FNAL E866/NuSea Collaboration combined with recently extracted Collins functions to calculate the $\\cos 2 \\phi$ asymmetries in unpolarized semi-inclusive deeply inelastic scattering (SIDIS) processes both for ZEUS at Hadron Electron Ring Accelerator (HERA) and Jefferson Lab experiments (JLab), and to compare our results with their data. We also give predictions for the $\\cos 2 \\phi$ asymmetries of SIDIS in the kinematical regime of HERMES Collaboration, and the forthcoming JLab experiments. We predict that the $\\cos 2 \\phi$ asymmetries of semi-inclusive $\\pi^-$ production are somewhat larger than that of $\\pi^+$ production. We suggest to measure these two processes separately, which will provide more detail information on the Boer-Mulders functions as well as on the Collins functions.

  6. DIS2002 | 00 All Robots Are Not Created Equal

    E-Print Network [OSTI]

    Kiesler, Sara

    contribute to people's perception of its humanness. To answer this question we analyzed 48 robots influence the perception of humanness in robot heads. This paper presents our findings and initial guidelines for the design of humanoid robot heads. Keywords human-robot interaction, social robots

  7. NSLS Celebrating the Accomplishments After 32 years of dis-

    E-Print Network [OSTI]

    their efficiency as a catalyst for fuel cells. The NSLS-II, scheduled for completion in 2015, will ac- commodate 60

  8. Deuteron Spin Structure Functions in the Resonance and DIS Regions

    SciTech Connect (OSTI)

    S. Kulagin; W. Melnitchouk

    2007-10-03

    We derive relations between spin-dependent nuclear and nucleon g_1 and g_2 structure functions, valid at all Q^2, and in both the resonance and deep inelastic regions. We apply the formalism to the specific case of the deuteron, which is often used as a source of neutron structure information, and compare the size of the nuclear corrections calculated using exact kinematics and using approximations applicable at large Q^2.

  9. Nuclear enhanced power corrections to DIS structure functions

    E-Print Network [OSTI]

    Xiaofeng Guo; Jianwei Qiu; Wei Zhu

    2001-10-03

    We calculate nuclear enhanced power corrections to structure functions measured in deeply inelastic lepton-nucleus scattering in Quantum Chromodynamics (QCD). We find that the nuclear medium enhanced power corrections at order of $O(\\alpha_s/Q^2)$ enhance the longitudinal structure function $F_L$, and suppress the transverse structure function $F_1$. We demonstrate that strong nuclear effects in $\\sigma_A/\\sigma_D$ and $R_A/R_D$, recently observed by HERMES Collaboration, can be explained in terms of the nuclear enhanced power corrections.

  10. Containing (Dis)order: A Cultural Geography of

    E-Print Network [OSTI]

    Sheldon, Nathan D.

    , Museum of London, Docklands; Matei Bejenaru; staff at The National Maritime Museum Library the formations of late capitalist modernity, particularly its role as a specific, but networked space between at UCA Library always facilitated my requests for various journal articles. In particular I would like

  11. Delineation of phylogenetically and adaptively distinct groups in the dis-

    E-Print Network [OSTI]

    salmon around the Pacific Rim may lead to conserva- tion of genetic diversity through an understanding to investi- gate regional and Pacific Rim varia- tion in chum salmon (Oncorhynchus keta Walbaum). Allozymes of chum salmon (Oncorhynchus keta) across the Pacific Rim, determined from microsatellite analysis Terry D

  12. HLA TIME MANAGEMENT AND DIS Richard M. Fujimoto

    E-Print Network [OSTI]

    , and 3) the Run­Time Infrastructure (RTI) that provides the software environment needed by the federates to exchange information in a coordinated fashion. The RTI is a special purpose distributed operating system will address the services concerning time management. The challenge to the RTI is to bring together

  13. HLA TIME MANAGEMENT AND DIS Richard M. Fujimoto

    E-Print Network [OSTI]

    , and 3) the Run-Time Infrastructure (RTI) that provides the software environment needed by the federates to exchange information in a coordinated fashion. The RTI is a special purpose distributed operating system will address the services concerning time management. The challenge to the RTI is to bring together

  14. News from the proton - recent DIS results from HERA

    SciTech Connect (OSTI)

    Meier, K. [Heidelberg Univ. (Germany)

    1997-01-01

    Recent results from the two large general-purpose detectors H1 and ZEUS at HERA (DESY, Hamburg, Germany) are presented. Emphasis is given to the analysis of deep inelastic scattering defined by the observation of the scattered electron or positron in the main calorimeters. Results on purely inclusive cross sections lead to a determination of the charged (quarks) parton distribution F{sub 2}(x, Q{sup 2}). Access to the electrically neutral parton content (gluons) is obtained indirectly by an analysis of the expected scaling violation behavior of F{sub 2} or directly from multijet rates originating from well-defined initial parton configurations. Finally, the recently uncovered subclass of large rapidity gap (LRG) events has been analyzed in terms of F{sub 2}. The result supports the concept of a color neutral object (Pomeron IP) being probed by a hard scattering electron. Evidence for factorization of the Pomeron radiation process as well as for scaling in the inclusive IP structure functions has been found.

  15. Construction, Concentration, and (Dis)Continuities in Social Valuations

    E-Print Network [OSTI]

    Zuckerman Sivan, Ezra W.

    I review and integrate recent sociological research that makes progress on three interrelated questions pertaining to social valuation: (a) the degree of social construction relative to objective constraints; (b) the degree ...

  16. (Dis)Organization and Success in an Economics MOOC

    E-Print Network [OSTI]

    Duflo, Esther

    Massive Online Open Courses (MOOCs) present the potential to deliver high quality education to a large number of students. But they suffer from low completion rates. This paper identifies disorganization as a factor behind ...

  17. Introduction The amber deposit of Oise has been recently dis-

    E-Print Network [OSTI]

    Rasmont, Pierre

    , France). The lignite layers containing the amber are from the Lower Eocene of the Paris basin (~53 Ma

  18. Absorption Heat Pumping- Have You Tried It? 

    E-Print Network [OSTI]

    Davis, R. C.

    1985-01-01

    The concept of a thermal powered absorption heat pump is not a new or revolutionary idea. It has been successfully demonstrated in the lab and prototypes have been installed in the field. Units have been successfully applied in a number...

  19. Summon [ try out ] How to use Summon

    E-Print Network [OSTI]

    Franssen, Michael

    '). The terms you enter may occur in the publication loose from one another. Put your search terms between: advanced search: enter search terms as words from publication titles #12;3 Type * to search for all endings: advanced search: enter search terms in specific search boxes Full-text linking in Summon Clicking

  20. Tri-Party Agreement Project Manager's List

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Faulk, D.A. Lyon, J. Kemp, C.J. Fletcher, T. W. Ecology Lead I Control Surface Water Infiltration Pathways As Needed M-045-61 Faulk, D.A. Lyon, J. Kemp, C.J. Fletcher, T. W....

  1. Constrained tri-sphere kinematic positioning system

    DOE Patents [OSTI]

    Viola, Robert J (Jackson, WY)

    2010-12-14

    A scalable and adaptable, six-degree-of-freedom, kinematic positioning system is described. The system can position objects supported on top of, or suspended from, jacks comprising constrained joints. The system is compatible with extreme low temperature or high vacuum environments. When constant adjustment is not required a removable motor unit is available.

  2. Tri-Party Agreement - Hanford Site

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout / TransformingTransuranic Waste RetrievalTrending:Agreement

  3. TriBITS Developers Guide and Reference

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout / TransformingTransuranic Waste

  4. Tri Alpha Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,

  5. Tri Power Systems Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems Inc Jump to:

  6. Proposed Tri-Party Agreement Modifications

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeedingProgramExemptions |(Conference)ProjectProposed SettlementofStructure

  7. Tri Global Energy LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EISTJThin Film SolarTown ofTransportToolkitTrenton, Michigan:IGlobal

  8. Tri State Biodiesel LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EISTJThin Film SolarTown ofTransportToolkitTrenton,

  9. CT-guided Bipolar and Multipolar Radiofrequency Ablation (RF Ablation) of Renal Cell Carcinoma: Specific Technical Aspects and Clinical Results

    SciTech Connect (OSTI)

    Sommer, C. M., E-mail: christof.sommer@med.uni-heidelberg.de [University Hospital Heidelberg, INF 110, Department of Diagnostic and Interventional Radiology (Germany); Lemm, G.; Hohenstein, E. [Minimally Invasive Therapies and Nuclear Medicine, SLK Kliniken Heilbronn GmbH, Clinic for Radiology (Germany); Bellemann, N.; Stampfl, U. [University Hospital Heidelberg, INF 110, Department of Diagnostic and Interventional Radiology (Germany); Goezen, A. S.; Rassweiler, J. [Clinic for Urology, SLK Kliniken Heilbronn GmbH (Germany); Kauczor, H. U.; Radeleff, B. A. [University Hospital Heidelberg, INF 110, Department of Diagnostic and Interventional Radiology (Germany); Pereira, P. L. [Minimally Invasive Therapies and Nuclear Medicine, SLK Kliniken Heilbronn GmbH, Clinic for Radiology (Germany)

    2013-06-15

    Purpose. This study was designed to evaluate the clinical efficacy of CT-guided bipolar and multipolar radiofrequency ablation (RF ablation) of renal cell carcinoma (RCC) and to analyze specific technical aspects between both technologies. Methods. We included 22 consecutive patients (3 women; age 74.2 {+-} 8.6 years) after 28 CT-guided bipolar or multipolar RF ablations of 28 RCCs (diameter 2.5 {+-} 0.8 cm). Procedures were performed with a commercially available RF system (Celon AG Olympus, Berlin, Germany). Technical aspects of RF ablation procedures (ablation mode [bipolar or multipolar], number of applicators and ablation cycles, overall ablation time and deployed energy, and technical success rate) were analyzed. Clinical results (local recurrence-free survival and local tumor control rate, renal function [glomerular filtration rate (GFR)]) and complication rates were evaluated. Results. Bipolar RF ablation was performed in 12 procedures and multipolar RF ablation in 16 procedures (2 applicators in 14 procedures and 3 applicators in 2 procedures). One ablation cycle was performed in 15 procedures and two ablation cycles in 13 procedures. Overall ablation time and deployed energy were 35.0 {+-} 13.6 min and 43.7 {+-} 17.9 kJ. Technical success rate was 100 %. Major and minor complication rates were 4 and 14 %. At an imaging follow-up of 15.2 {+-} 8.8 months, local recurrence-free survival was 14.4 {+-} 8.8 months and local tumor control rate was 93 %. GFR did not deteriorate after RF ablation (50.8 {+-} 16.6 ml/min/1.73 m{sup 2} before RF ablation vs. 47.2 {+-} 11.9 ml/min/1.73 m{sup 2} after RF ablation; not significant). Conclusions. CT-guided bipolar and multipolar RF ablation of RCC has a high rate of clinical success and low complication rates. At short-term follow-up, clinical efficacy is high without deterioration of the renal function.

  10. HDRMC, an accelerated Monte Carlo dose calculator for high dose rate brachytherapy with CT-compatible applicators

    SciTech Connect (OSTI)

    Chibani, Omar C-M Ma, Charlie

    2014-05-15

    Purpose: To present a new accelerated Monte Carlo code for CT-based dose calculations in high dose rate (HDR) brachytherapy. The new code (HDRMC) accounts for both tissue and nontissue heterogeneities (applicator and contrast medium). Methods: HDRMC uses a fast ray-tracing technique and detailed physics algorithms to transport photons through a 3D mesh of voxels representing the patient anatomy with applicator and contrast medium included. A precalculated phase space file for the{sup 192}Ir source is used as source term. HDRM is calibrated to calculated absolute dose for real plans. A postprocessing technique is used to include the exact density and composition of nontissue heterogeneities in the 3D phantom. Dwell positions and angular orientations of the source are reconstructed using data from the treatment planning system (TPS). Structure contours are also imported from the TPS to recalculate dose-volume histograms. Results: HDRMC was first benchmarked against the MCNP5 code for a single source in homogenous water and for a loaded gynecologic applicator in water. The accuracy of the voxel-based applicator model used in HDRMC was also verified by comparing 3D dose distributions and dose-volume parameters obtained using 1-mm{sup 3} versus 2-mm{sup 3} phantom resolutions. HDRMC can calculate the 3D dose distribution for a typical HDR cervix case with 2-mm resolution in 5 min on a single CPU. Examples of heterogeneity effects for two clinical cases (cervix and esophagus) were demonstrated using HDRMC. The neglect of tissue heterogeneity for the esophageal case leads to the overestimate of CTV D90, CTV D100, and spinal cord maximum dose by 3.2%, 3.9%, and 3.6%, respectively. Conclusions: A fast Monte Carlo code for CT-based dose calculations which does not require a prebuilt applicator model is developed for those HDR brachytherapy treatments that use CT-compatible applicators. Tissue and nontissue heterogeneities should be taken into account in modern HDR brachytherapy planning.

  11. Proton Radiography Studies for Proton CT M. Petterson, N. Blumenkrantz, J. Feldt, J. Heimann, D. Lucia, A. Seiden, D. C. Williams, H. F.-W. Sadrozinski,

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    Proton Radiography Studies for Proton CT M. Petterson, N. Blumenkrantz, J. Feldt, J. Heimann, D. Randazzo, V. Sipala Abstract­We report the results of a beam experiment to develop proton Computed of a phantom to predict the path of the proton within the phantom and of a crystal calorimeter to measure

  12. A detailed pore characterization in 2D and 3D by means of optical and fluorescence microscopy combined with high-resolution X-ray CT.

    E-Print Network [OSTI]

    Gent, Universiteit

    A detailed pore characterization in 2D and 3D by means of optical and fluorescence microscopy structure. However, the evolution of techniques like X-ray CT has enabled us to make non-destructive 3D images of materials and thus of rocks. 3D image analysis software enables us to characterize the pore

  13. Summer and early-fall sea-ice concentration in the Ross Sea: comparison of in situ ASPeCt observations and satellite passive

    E-Print Network [OSTI]

    Texas at San Antonio, University of

    Ct observations and satellite passive microwave estimates Margaret A. KNUTH,1 Stephen F. ACKLEY2 1 Department in situ datasets were then compared with ice concentrations from SSM/I passive microwave satellite data) in 1972, passive microwave satellite remote sensing has been used to provide scientists with sea

  14. ModPET: A Novel Small-Animal PET System Positron Emission Tomography (PET) and PET/CT systems have become the gold standard for imaging

    E-Print Network [OSTI]

    Arizona, University of

    for Gamma-Ray Imaging, we are developing a novel small-animal PET scanner that utilizes common modularModPET: A Novel Small-Animal PET System Positron Emission Tomography (PET) and PET/CT systems have these results to their human counterparts. Current small-animal PET scanners are very costly and complicated

  15. 1. Birru, D., C.-T. Chou, and A. Seyedi, "Coordination in Wireless Networks Having Devices with Different Physical Layer Transmission Schemes," US Patent 8233505, Jul. 31, 2012.

    E-Print Network [OSTI]

    Pattanaik, Sumanta N.

    Patents 1. Birru, D., C.-T. Chou, and A. Seyedi, "Coordination in Wireless Networks Having Devices with Different Physical Layer Transmission Schemes," US Patent 8233505, Jul. 31, 2012. 2. Birru, D. and A. Seyedi, "Cost-Effective Preamble Structure for High-Speed Communication of Packetized System," US Patent 8

  16. Optimal Design of High Speed Mechanical Systems J.W. David, C.Y. Cheng, T.D. Choi, C.T. Kelley, and J. Gablonsky

    E-Print Network [OSTI]

    Optimal Design of High Speed Mechanical Systems by J.W. David, C.Y. Cheng, T.D. Choi, C.T. Kelley mechanical systems has naturally led to the need to design such systems in an optimal fashion. Lighter sophistication of mechanical equipment. Even with the advent of modern computer­aided design tools, the dynamic

  17. Filtered Iterative Reconstruction (FIR) via Proximal Forward-Backward Splitting: A Synergy of Analytical and Iterative Reconstruction Method for CT

    E-Print Network [OSTI]

    Gao, Hao

    2015-01-01

    This work is to develop a general framework, namely filtered iterative reconstruction (FIR) method, to incorporate analytical reconstruction (AR) method into iterative reconstruction (IR) method, for enhanced CT image quality. Specifically, FIR is formulated as a combination of filtered data fidelity and sparsity regularization, and then solved by proximal forward-backward splitting (PFBS) algorithm. As a result, the image reconstruction decouples data fidelity and image regularization with a two-step iterative scheme, during which an AR-projection step updates the filtered data fidelity term, while a denoising solver updates the sparsity regularization term. During the AR-projection step, the image is projected to the data domain to form the data residual, and then reconstructed by certain AR to a residual image which is in turn weighted together with previous image iterate to form next image iterate. Since the eigenvalues of AR-projection operator are close to the unity, PFBS based FIR has a fast convergenc...

  18. SU-E-I-98: Dose Comparison for Pulmonary Embolism CT Studies: Single Energy Vs. Dual Energy

    SciTech Connect (OSTI)

    Mahmood, U; Erdi, Y

    2014-06-01

    Purpose: The purpose of this study was to assess and compare the size specific dose estimate (SSDE), dose length product (DLP) and noise relationship for pulmonary embolism studies evaluated by single source dual energy computed tomography (DECT) against conventional CT (CCT) studies in a busy cancer center and to determine the dose savings provided by DECT. Methods: An IRB-approved retrospective study was performed to determine the CTDIvol and DLP from a subset of patients scanned with both DECT and CCT over the past five years. We were able to identify 30 breast cancer patients (6 male, 24 female, age range 24 to 81) who had both DECT and CCT studies performed. DECT scans were performed with a GE HD 750 scanner (140/80 kVp, 480 mAs and 40 mm) and CCT scans were performed with a GE Lightspeed 16 slice scanner (120 kVp, 352 mAs, 20 mm). Image noise was measured by placing an ROI and recording the standard deviation of the mean HU along the descending aorta. Results: The average DECT patient size specific dose estimate was to be 14.2 ± 1.7 mGy as compared to 22.4 ± 2.7 mGy from CCT PE studies, which is a 37% reduction in the SSDE. The average DECT DLP was 721.8 ± 84.6 mGy-cm as compared to 981.8 ± 106.1 mGy-cm for CCT, which is a 26% decrease. Compared to CCT the image noise was found to decrease by 19% when using DECT for PE studies. Conclusion: DECT SSDE and DLP measurements indicate dose savings and image noise reduction when compared to CCT. In an environment that heavily debates CT patient doses, this study confirms the effectiveness of DECT in PE imaging.

  19. SU-E-I-90: Medical Physicists' Implication in Diagnostic CT in Switzerland: Results of After One Year of Experience

    SciTech Connect (OSTI)

    Ryckx, N.; Elandoy, C.; Bize, J.; Verdun, F.R. [Lausanne University Hospital, Lausanne, VD (Switzerland)

    2014-06-01

    Purpose: Since January 1st 2008, the Swiss ordinance on radiation protection requires the involvement of a medical physicist to support the optimization process of medical imaging techniques using ionizing radiation. After a long process of implementation, this requirement is satisfied all over the country since the beginning of 2013. The goal of this contribution is to summarize the main results obtained in this first year of experience in CT. Methods: We assessed the output and clinical use of 45 CT units using a three-pronged approach. First, we assessed the output of the device (CTDIvol, primary beam collimation and HU in water at different tube tensions). Secondly, we characterized the local chest and abdomen acquisition and reconstruction protocols using the Catphan 600 phantom. Lastly, we assessed the clinical use of the machine by analyzing an extract of a dozen clinical examinations per unit. Results: 9 out of 45 units had incorrect collimator settings, e.g. 4mm instead of 1mm. We witnessed also a large spread in reconstruction parameters, especially for reconstructed slice thickness, thus showing notable variations in low contrast detectability performances. Clinical practice is also clearly spread out. For example, estimated patient effective dose per abdomen examination lies at 18.7+/?12.7mSv (min: 2.0mSv — max: 112.0mSv). Chest and brain scans have a narrower dispersion, but patient effective dose is also spread by about a factor of 10 to 20. Conclusion: The spread in clinical practice being fairly large, it appears of crucial importance to collaborate more closely with radiologists and technologists to assess it. The lack of statistical precision will imply that we analyze clinical practice according to a specific medical demand rather than an anatomical region. Furthermore, low contrast sensitivity (LCD) being a crucial parameter, an objective method using a model observer will be used to assess LCD.

  20. Effect of Tb{sup 3+} concentration on the optical and vibrational properties of YBO{sub 3} tri-doped with Eu{sup 3+}, Ce{sup 3+}, and Tb{sup 3+}

    SciTech Connect (OSTI)

    Sohal, S.; Hassanzadeh, E.; Huang, J. Y. [Department of Physics, Texas Tech University and Nano Tech Center, Lubbock, Texas 79409 (United States); Nazari, M.; Holtz, M., E-mail: mark.holtz@txstate.edu [Department of Physics, Texas State University, San Marcos, Texas 78666 (United States); Zhang, X.; Chaudhuri, J. [Department of Mechanical Engineering, Texas Tech University, Lubbock, Texas 79409 (United States); Kuryatkov, V. V. [Department of Electrical and Computer Engineering and Nano Tech Center, Texas Tech University, Lubbock, Texas 79409 (United States); Hope-Weeks, L. J. [Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409 (United States)

    2014-05-14

    Structural and optical studies are reported of yttrium orthoborate YBO{sub 3} when tri-doped with Eu{sup 3+}, Ce{sup 3+}, and Tb{sup 3+}, focusing on the role of terbium concentration. Incorporation of Tb{sup 3+} affects emission properties for photoluminescence (PL) excited by near ultraviolet light. For constant cerium and europium concentrations, increasing the Tb{sup 3+} results in diminished PL from the Ce{sup 3+} and Tb{sup 3+} color centers. Simultaneously, the PL excitation bands related to both Ce{sup 3+} and Tb{sup 3+} increase in intensity for red emission from the Eu{sup 3+}. Results are consistent with a Ce{sup 3+}???(Tb{sup 3+}){sub n}???Eu{sup 3+} energy transfer scheme, where (Tb{sup 3+}){sub n} denotes a chain incorporating n terbium ions. A high red to orange PL intensity ratio is obtained, ranging from 1.34 to 2.09. Raman vibrational bands show a systematic change, with Tb{sup 3+} concentration, in the B{sub 3}O{sub 9} ring terminal oxygen bending mode coordinated with the yttrium site where dopant ions substitute. The structural changes are interpreted as variations in the local neighborhood of these sites in the YBO{sub 3}:Ce{sup 3+},Tb{sup 3+},Eu{sup 3+} crystal structure.

  1. SU-E-J-151: Dosimetric Evaluation of DIR Mapped Contours for Image Guided Adaptive Radiotherapy with 4D Cone-Beam CT

    SciTech Connect (OSTI)

    Balik, S; Weiss, E; Williamson, J; Hugo, G; Jan, N; Zhang, L; Roman, N; Christensen, G

    2014-06-01

    Purpose: To estimate dosimetric errors resulting from using contours deformably mapped from planning CT to 4D cone beam CT (CBCT) images for image-guided adaptive radiotherapy of locally advanced non-small cell lung cancer (NSCLC). Methods: Ten locally advanced non-small cell lung cancer (NSCLC) patients underwent one planning 4D fan-beam CT (4DFBCT) and weekly 4DCBCT scans. Multiple physicians delineated the gross tumor volume (GTV) and normal structures in planning CT images and only GTV in CBCT images. Manual contours were mapped from planning CT to CBCTs using small deformation, inverse consistent linear elastic (SICLE) algorithm for two scans in each patient. Two physicians reviewed and rated the DIR-mapped (auto) and manual GTV contours as clinically acceptable (CA), clinically acceptable after minor modification (CAMM) and unacceptable (CU). Mapped normal structures were visually inspected and corrected if necessary, and used to override tissue density for dose calculation. CTV (6mm expansion of GTV) and PTV (5mm expansion of CTV) were created. VMAT plans were generated using the DIR-mapped contours to deliver 66 Gy in 33 fractions with 95% and 100% coverage (V66) to PTV and CTV, respectively. Plan evaluation for V66 was based on manual PTV and CTV contours. Results: Mean PTV V66 was 84% (range 75% – 95%) and mean CTV V66 was 97% (range 93% – 100%) for CAMM scored plans (12 plans); and was 90% (range 80% – 95%) and 99% (range 95% – 100%) for CA scored plans (7 plans). The difference in V66 between CAMM and CA was significant for PTV (p = 0.03) and approached significance for CTV (p = 0.07). Conclusion: The quality of DIR-mapped contours directly impacted the plan quality for 4DCBCT-based adaptation. Larger safety margins may be needed when planning with auto contours for IGART with 4DCBCT images. Reseach was supported by NIH P01CA116602.

  2. SU-E-I-63: Quantitative Evaluation of the Effects of Orthopedic Metal Artifact Reduction (OMAR) Software On CT Images for Radiotherapy Simulation

    SciTech Connect (OSTI)

    Jani, S [Sharp Memorial Hospital, San Diego, CA (United States)

    2014-06-01

    Purpose: CT simulation for patients with metal implants can often be challenging due to artifacts that obscure tumor/target delineation and normal organ definition. Our objective was to evaluate the effectiveness of Orthopedic Metal Artifact Reduction (OMAR), a commercially available software, in reducing metal-induced artifacts and its effect on computed dose during treatment planning. Methods: CT images of water surrounding metallic cylindrical rods made of aluminum, copper and iron were studied in terms of Hounsfield Units (HU) spread. Metal-induced artifacts were characterized in terms of HU/Volume Histogram (HVH) using the Pinnacle treatment planning system. Effects of OMAR on enhancing our ability to delineate organs on CT and subsequent dose computation were examined in nine (9) patients with hip implants and two (2) patients with breast tissue expanders. Results: Our study characterized water at 1000 HU with a standard deviation (SD) of about 20 HU. The HVHs allowed us to evaluate how the presence of metal changed the HU spread. For example, introducing a 2.54 cm diameter copper rod in water increased the SD in HU of the surrounding water from 20 to 209, representing an increase in artifacts. Subsequent use of OMAR brought the SD down to 78. Aluminum produced least artifacts whereas Iron showed largest amount of artifacts. In general, an increase in kVp and mA during CT scanning showed better effectiveness of OMAR in reducing artifacts. Our dose analysis showed that some isodose contours shifted by several mm with OMAR but infrequently and were nonsignificant in planning process. Computed volumes of various dose levels showed <2% change. Conclusions: In our experience, OMAR software greatly reduced the metal-induced CT artifacts for the majority of patients with implants, thereby improving our ability to delineate tumor and surrounding organs. OMAR had a clinically negligible effect on computed dose within tissues. Partially funded by unrestricted educational grant from Philips.

  3. *Tri-Generation is a novel technology that was conceived by the National Fuel Cell Research Center in 2001 to simultaneously generate electricity, hydrogen, and heat. It was developed into the first prototype in collaboration with FuelCell Energy, Inc., a

    E-Print Network [OSTI]

    Mease, Kenneth D.

    in 2001 to simultaneously generate electricity, hydrogen, and heat. It was developed into the first District while operated on renewable biogas derived from the wastewater treatment process. For more/solar - liquid truck... On-site Hydrogen from photovoltaic electrolysis Hydrogen from Tri-Generation* - Biogas

  4. Noise, sampling, and the number of projections in cone-beam CT with a flat-panel detector

    SciTech Connect (OSTI)

    Zhao, Z.; Gang, G. J.; Siewerdsen, J. H.

    2014-06-15

    Purpose: To investigate the effect of the number of projection views on image noise in cone-beam CT (CBCT) with a flat-panel detector. Methods: This fairly fundamental consideration in CBCT system design and operation was addressed experimentally (using a phantom presenting a uniform medium as well as statistically motivated “clutter”) and theoretically (using a cascaded systems model describing CBCT noise) to elucidate the contributing factors of quantum noise (?{sub Q}), electronic noise (?{sub E}), and view aliasing (?{sub view}). Analysis included investigation of the noise, noise-power spectrum, and modulation transfer function as a function of the number of projections (N{sub proj}), dose (D{sub tot}), and voxel size (b{sub vox}). Results: The results reveal a nonmonotonic relationship between image noise andN{sub proj} at fixed total dose: for the CBCT system considered, noise decreased with increasing N{sub proj} due to reduction of view sampling effects in the regime N{sub proj} CT, owing to the relatively high electronic noise in FPDs. The analysis explicitly relates view aliasing and quantum noise in a manner that includes aspects of the object (“clutter”) and imaging chain (including nonidealities of detector blur and electronic noise) to provide a more rigorous basis for commonly held intuition and heurism in CBCT system design and operation.

  5. SU-D-12A-02: DeTECT, a Method to Enhance Soft Tissue Contrast From Mega Voltage CT

    SciTech Connect (OSTI)

    Sheng, K; Gou, S; Qi, S

    2014-06-01

    Purpose: MVCT images have been used on TomoTherapy system to align patients based on bony anatomies but its usefulness for soft tissue registration, delineation and adaptive radiation therapy is severely limited due to minimal photoelectric interaction and prominent presence of noise resulting from low detector quantum efficiency of megavoltage x-rays. We aim to utilize a non-local means denoising method and texture analysis to recover the soft tissue information for MVCT. Methods: A block matching 3D (BM3D) algorithm was adapted to reduce the noise while keeping the texture information of the MVCT images. BM3D is an imaging denoising algorithm developed from non-local means methods. BM3D additionally creates 3D groups by stacking 2D patches by the order of similarity. 3D denoising operation is then performed. The resultant 3D group is inversely transformed back to 2D images. In this study, BM3D was applied to MVCT images of a CT quality phantom, a head and neck and a prostate patient. Following denoising, imaging texture was enhanced to create the denoised and texture enhanced CT (DeTECT). Results: The original MVCT images show prevalent noise and poor soft tissue contrast. By applying BM3D denoising and texture enhancement, all MVCT images show remarkable improvements. For the phantom, the contrast to noise ratio for the low contrast plug was improved from 2.2 to 13.1 without compromising line pair conspicuity. For the head and neck patient, the lymph nodes and vein in the carotid space inconspicuous in the original MVCT image becomes highly visible in DeTECT. For the prostate patient, the boundary between the bladder and the prostate in the original MVCT is successfully recovered. Both results are visually validated by kVCT images of the corresponding patients. Conclusion: DeTECT showed the promise to drastically improve the soft tissue contrast of MVCT for image guided radiotherapy and adaptive radiotherapy.

  6. SU-E-J-267: Weekly Volumetric and Dosimetric Changes in Adaptive Conformal Radiotherapy of Non-Small-Cell-Lung Cancer Using 4D CT and Gating

    SciTech Connect (OSTI)

    Li, Z [the 6th People's Hospital of Shanghai Jiaotong University, Shanghai, Shanghai (China); Cleveland Clinic, Cleveland, OH (United States); Shang, Q [Cleveland Clinic, Cleveland, OH (United States); Xiong, F; Zhang, X; Zhang, Q; Fu, S [the 6th People's Hospital of Shanghai Jiaotong University, Shanghai, Shanghai (China)

    2014-06-01

    Purpose: This study was to evaluate the significance of weekly imageguided patient setup and to assess the volumetric and dosimetric changes in no-small-cell-lung cancer (NSCLC) patients treated with adaptive conformal radiotherapy (CRT). Methods: 9 NSCLC patients treated with 3D CRT underwent 4D CT-on-rail every five fractions. ITV was generated from three phases of the 4DCT (the end of exhalation, 25% before and after the end of exhalation). The margin of ITV to PTV is 5mm. 6 weekly CTs were acquired for each patient. The weekly CTs were fused with the planning CT by vertebrae. The couch shift was recorded for each weekly CT to evaluate the setup error. The gross tumor volumes (GTVs) were contoured on weekly CT images by a physician. Beams from the original plans were applied to weekly CTs to calculate the delivered doses. All patients underwent replanning after 20 fractions. Results: Among the total 54 CTs, the average setup error was 2.0± 1.7, 2.6± 2.1, 2.7± 2.2 mm in X, Y, and Z direction, respectively. The average volume of the primary GTV was reduced from 42.45 cc to 22.78 cc (47.04%) after 6 weeks. The maximal volume regression occurred between 15 and 20 fractions. Adaptive radiation therapy (ART) reduced the V20 and V5 of the lung by 33.5% and 16.89%, respectively. ART also reduced Dmean and D1/3 of the heart by 31.7% and 32.32%, respectively. Dmax of the spinal cord did not vary much during the treatment course. Conclusion: 5 mm margin is sufficient for 4D weekly CTguided radiotherapy in lung cancer. Tumor regression was observed in the majority of patients. ART significantly reduced the OARs dose. Our preliminary results indicated that an off-line ART approach is appropriate in clinical practice.

  7. Utility of Megavoltage Fan-Beam CT for Treatment Planning in a Head-And-Neck Cancer Patient with Extensive Dental Fillings Undergoing Helical Tomotherapy

    SciTech Connect (OSTI)

    Yang, Claus; Liu Tianxiao; Jennelle, Richard L.; Ryu, Janice K.; Vijayakumar, Srinivasan; Purdy, James A. [Department of Radiation Oncology, University of California Davis School of Medicine, Sacramento, CA (United States); Chen, Allen M. [Department of Radiation Oncology, University of California Davis School of Medicine, Sacramento, CA (United States)], E-mail: allen.chen@ucdmc.ucdavis.edu

    2010-07-01

    The purpose of this study was to demonstrate the potential utility of megavoltage fan-beam computed tomography (MV-FBCT) for treatment planning in a patient undergoing helical tomotherapy for nasopharyngeal carcinoma in the presence of extensive dental artifact. A 28-year-old female with locally advanced nasopharyngeal carcinoma presented for radiation therapy. Due to the extensiveness of the dental artifact present in the oral cavity kV-CT scan acquired at simulation, which made treatment planning impossible on tomotherapy planning system, MV-FBCT imaging was obtained using the HI-ART tomotherapy treatment machine, with the patient in the treatment position, and this information was registered with her original kV-CT scan for the purposes of structure delineation, dose calculation, and treatment planning. To validate the feasibility of the MV-FBCT-generated treatment plan, an electron density CT phantom (model 465, Gammex Inc., Middleton, WI) was scanned using MV-FBCT to obtain CT number to density table. Additionally, both a 'cheese' phantom (which came with the tomotherapy treatment machine) with 2 inserted ion chambers and a generic phantom called Quasar phantom (Modus Medical Devices Inc., London, ON, Canada) with one inserted chamber were used to confirm dosimetric accuracy. The MV-FBCT could be used to clearly visualize anatomy in the region of the dental artifact and provide sufficient soft-tissue contrast to assist in the delineation of normal tissue structures and fat planes. With the elimination of the dental artifact, the MV-FBCT images allowed more accurate dose calculation by the tomotherapy system. It was confirmed that the phantom material density was determined correctly by the tomotherapy MV-FBCT number to density table. The ion chamber measurements agreed with the calculations from the MV-FBCT generated phantom plan within 2%. MV-FBCT may be useful in radiation treatment planning for nasopharyngeal cancer patients in the setting of extensive dental artifacts.

  8. Influence of radiation therapy on the lung-tissue in breast cancer patients: CT-assessed density changes and associated symptoms

    SciTech Connect (OSTI)

    Rotstein, S.; Lax, I.; Svane, G. )

    1990-01-01

    The relative electron density of lung tissue was measured from computer tomography (CT) slices in 33 breast cancer patients treated by various techniques of adjuvant radiotherapy. The measurements were made before radiotherapy, 3 months and 9 months after completion of radiation therapy. The changes in lung densities at 3 months and 9 months were compared to radiation induced radiological (CT) findings. In addition, subjective symptoms such as cough and dyspnoea were assessed before and after radiotherapy. It was observed that the mean of the relative electron density of lung tissue varied from 0.25 when the whole lung was considered to 0.17 when only the anterior lateral quarter of the lung was taken into account. In patients with positive radiological (CT) findings the mean lung density of the anterior lateral quarter increased 2.1 times 3 months after radiotherapy and was still increased 1.6 times 6 months later. For those patients without findings, in the CT pictures the corresponding values were 1.2 and 1.1, respectively. The standard deviation of the pixel values within the anterior lateral quarter of the lung increased 3.8 times and 3.2 times at 3 months and 9 months, respectively, in the former group, as opposed to 1.2 and 1.1 in the latter group. Thirteen patients had an increase in either cough or dyspnoea as observed 3 months after completion of radiotherapy. In eleven patients these symptoms persisted 6 months later. No significant correlation was found between radiological findings and subjective symptoms. However, when three different treatment techniques were compared among 29 patients the highest rate of radiological findings was observed in patients in which the largest lung volumes received the target dose. A tendency towards an increased rate of subjective symptoms was also found in this group.

  9. Percutaneous Radiofrequency Ablation for the Treatment of Liver Neoplasms in the Caudate Lobe Left of the Vena Cava: Electrode Placement Through the Left Lobe of the Liver Under CT-Fluoroscopic Guidance

    SciTech Connect (OSTI)

    Yamakado, Koichiro, E-mail: yama@clin.medic.mie-u.ac.jp; Nakatsuka, Atsuhiro; Akeboshi, Masao; Takaki, Haruyuki; Takeda, Kan [Mie University School of Medicine, Department of Radiology (Japan)

    2005-06-15

    Five hepatocellular carcinomas and one liver metastasis located in the caudate lobe left of the inferior vena cava were successfully treated by radiofrequency (RF) ablation by placing the RF electrode into each tumor through the left lobe of the liver under the CT-fluoroscopic guidance. All tumors were free of enhancement on dynamic contrast-enhanced CT during the mean follow-up period of 6.3 months. There were no major complications related to the procedures.

  10. An anthropomorphic multimodality (CT/MRI) phantom prototype for end-to-end tests in radiation therapy

    E-Print Network [OSTI]

    Gallas, Raya R; Runz, Armin; Niebuhr, Nina I; Jäkel, Oliver; Greilich, Steffen

    2014-01-01

    With the increasing complexity of external beam therapy, so-called "end-to-end" tests are intended to cover all steps from therapy planning to follow-up to fulfill the high demands on quality assurance. As magnetic resonance imaging (MRI) gains growing importance in the treatment process and established phantoms (such as the Alderson head) cannot be used for those tests, novel multimodality phantoms have to be developed. Here, we present a feasibility study for such a customizable multimodality head phantom. We used a set of patient CT images as the basis for the anthropomorphic head shape. The recipient - consisting of an epoxy resin - was produced using rapid prototyping (3D printing). The phantom recipient includes a nasal air cavity, two soft tissues volumes and cranial bone. Additionally a spherical tumor volume was positioned in the center. The volumes were filled with dipotassium phosphate-based cranial bone surrogate, agarose gel, and distilled water. The tumor volume was filled with normoxic dosimetr...

  11. FDG-PET/CT Imaging Predicts Histopathologic Treatment Responses after Neoadjuvant Therapy in Adult Primary Bone Sarcomas

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Benz, Matthias R.; Czernin, Johannes; Tap, William D.; Eckardt, Jeffrey J.; Seeger, Leanne L.; Allen-Auerbach, Martin S.; Dry, Sarah M.; Phelps, Michael E.; Weber, Wolfgang A.; Eilber, Fritz C.

    2010-01-01

    Purpose. The aim of this study was to prospectively evaluate whether FDG-PET allows an accurate assessment of histopathologic response to neoadjuvant treatment in adult patients with primary bone sarcomas.Methods. Twelve consecutive patients with resectable, primary high grade bone sarcomas were enrolled prospectively. FDG-PET/CT imaging was performed prior to the initiation and after completion of neoadjuvant treatment. Imaging findings were correlated with histopathologic response.Results. Histopathologic responders showed significantly more pronounced decreases in tumor FDG-SUVmax from baseline to late follow up than non-responders (64±19% versus29±30%, resp.;P=.03). Using a 60% decrease in tumor FDG-uptake as a threshold for metabolic response correctly classified 3more »of 4 histopathologic responders and 7 of 8 histopathologic non-responders as metabolic responders and non-responders, respectively (sensitivity, 75%; specificity, 88%).Conclusion. These results suggest that changes in FDG-SUVmax at the end of neoadjuvant treatment can identify histopathologic responders and non-responders in adult primary bone sarcoma patients.« less

  12. SU-E-J-250: A Methodology for Active Bone Marrow Protection for Cervical Cancer Intensity-Modulated Radiotherapy Using 18F-FLT PET/CT Image

    SciTech Connect (OSTI)

    Ma, C; Yin, Y

    2014-06-01

    Purpose: The purpose of this study was to compare a radiation therapy treatment planning that would spare active bone marrow and whole pelvic bone marrow using 18F FLT PET/CT image. Methods: We have developed an IMRT planning methodology to incorporate functional PET imaging using 18F FLT/CT scans. Plans were generated for two cervical cancer patients, where pelvicactive bone marrow region was incorporated as avoidance regions based on the range: SUV>2., another region was whole pelvic bone marrow. Dose objectives were set to reduce the volume of active bone marrow and whole bone marraw. The volumes of received 10 (V10) and 20 (V20) Gy for active bone marrow were evaluated. Results: Active bone marrow regions identified by 18F FLT with an SUV>2 represented an average of 48.0% of the total osseous pelvis for the two cases studied. Improved dose volume histograms for identified bone marrow SUV volumes and decreases in V10(average 18%), and V20(average 14%) were achieved without clinically significant changes to PTV or OAR doses. Conclusion: Incorporation of 18F FLT/CT PET in IMRT planning provides a methodology to reduce radiation dose to active bone marrow without compromising PTV or OAR dose objectives in cervical cancer.

  13. Tri-Generation Success Story: World's First Tri-Gen Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:Financing ToolInternational Affairs,Department ofARPA-E Top

  14. CT head-scan dosimetry in an anthropomorphic phantom and associated measurement of ACR accreditation-phantom imaging metrics under clinically representative scan conditions

    SciTech Connect (OSTI)

    Brunner, Claudia C.; Stern, Stanley H.; Chakrabarti, Kish; Minniti, Ronaldo; Parry, Marie I.; Skopec, Marlene

    2013-08-15

    Purpose: To measure radiation absorbed dose and its distribution in an anthropomorphic head phantom under clinically representative scan conditions in three widely used computed tomography (CT) scanners, and to relate those dose values to metrics such as high-contrast resolution, noise, and contrast-to-noise ratio (CNR) in the American College of Radiology CT accreditation phantom.Methods: By inserting optically stimulated luminescence dosimeters (OSLDs) in the head of an anthropomorphic phantom specially developed for CT dosimetry (University of Florida, Gainesville), we measured dose with three commonly used scanners (GE Discovery CT750 HD, Siemens Definition, Philips Brilliance 64) at two different clinical sites (Walter Reed National Military Medical Center, National Institutes of Health). The scanners were set to operate with the same data-acquisition and image-reconstruction protocols as used clinically for typical head scans, respective of the practices of each facility for each scanner. We also analyzed images of the ACR CT accreditation phantom with the corresponding protocols. While the Siemens Definition and the Philips Brilliance protocols utilized only conventional, filtered back-projection (FBP) image-reconstruction methods, the GE Discovery also employed its particular version of an adaptive statistical iterative reconstruction (ASIR) algorithm that can be blended in desired proportions with the FBP algorithm. We did an objective image-metrics analysis evaluating the modulation transfer function (MTF), noise power spectrum (NPS), and CNR for images reconstructed with FBP. For images reconstructed with ASIR, we only analyzed the CNR, since MTF and NPS results are expected to depend on the object for iterative reconstruction algorithms.Results: The OSLD measurements showed that the Siemens Definition and the Philips Brilliance scanners (located at two different clinical facilities) yield average absorbed doses in tissue of 42.6 and 43.1 mGy, respectively. The GE Discovery delivers about the same amount of dose (43.7 mGy) when run under similar operating and image-reconstruction conditions, i.e., without tube current modulation and ASIR. The image-metrics analysis likewise showed that the MTF, NPS, and CNR associated with the reconstructed images are mutually comparable when the three scanners are run with similar settings, and differences can be attributed to different edge-enhancement properties of the applied reconstruction filters. Moreover, when the GE scanner was operated with the facility's scanner settings for routine head exams, which apply 50% ASIR and use only approximately half of the 100%-FBP dose, the CNR of the images showed no significant change. Even though the CNR alone is not sufficient to characterize the image quality and justify any dose reduction claims, it can be useful as a constancy test metric.Conclusions: This work presents a straightforward method to connect direct measurements of CT dose with objective image metrics such as high-contrast resolution, noise, and CNR. It demonstrates that OSLD measurements in an anthropomorphic head phantom allow a realistic and locally precise estimation of magnitude and spatial distribution of dose in tissue delivered during a typical CT head scan. Additional objective analysis of the images of the ACR accreditation phantom can be used to relate the measured doses to high contrast resolution, noise, and CNR.

  15. Predicting target vessel location on robot-assisted coronary artery bypass graft using CT to ultrasound registration

    SciTech Connect (OSTI)

    Cho, Daniel S.; Linte, Cristian; Chen, Elvis C. S.; Bainbridge, Daniel; Wedlake, Chris; Moore, John; Barron, John; Patel, Rajni; Peters, Terry

    2012-03-15

    Purpose: Although robot-assisted coronary artery bypass grafting (RA-CABG) has gained more acceptance worldwide, its success still depends on the surgeon's experience and expertise, and the conversion rate to full sternotomy is in the order of 15%-25%. One of the reasons for conversion is poor pre-operative planning, which is based solely on pre-operative computed tomography (CT) images. In this paper, the authors propose a technique to estimate the global peri-operative displacement of the heart and to predict the intra-operative target vessel location, validated via both an in vitro and a clinical study. Methods: As the peri-operative heart migration during RA-CABG has never been reported in the literatures, a simple in vitro validation study was conducted using a heart phantom. To mimic the clinical workflow, a pre-operative CT as well as peri-operative ultrasound images at three different stages in the procedure (Stage{sub 0}--following intubation; Stage{sub 1}--following lung deflation; and Stage{sub 2}--following thoracic insufflation) were acquired during the experiment. Following image acquisition, a rigid-body registration using iterative closest point algorithm with the robust estimator was employed to map the pre-operative stage to each of the peri-operative ones, to estimate the heart migration and predict the peri-operative target vessel location. Moreover, a clinical validation of this technique was conducted using offline patient data, where a Monte Carlo simulation was used to overcome the limitations arising due to the invisibility of the target vessel in the peri-operative ultrasound images. Results: For the in vitro study, the computed target registration error (TRE) at Stage{sub 0}, Stage{sub 1}, and Stage{sub 2} was 2.1, 3.3, and 2.6 mm, respectively. According to the offline clinical validation study, the maximum TRE at the left anterior descending (LAD) coronary artery was 4.1 mm at Stage{sub 0}, 5.1 mm at Stage{sub 1}, and 3.4 mm at Stage{sub 2}. Conclusions: The authors proposed a method to measure and validate peri-operative shifts of the heart during RA-CABG. In vitro and clinical validation studies were conducted and yielded a TRE in the order of 5 mm for all cases. As the desired clinical accuracy imposed by this procedure is on the order of one intercostal space (10-15 mm), our technique suits the clinical requirements. The authors therefore believe this technique has the potential to improve the pre-operative planning by updating peri-operative migration patterns of the heart and, consequently, will lead to reduced conversion to conventional open thoracic procedures.

  16. SU-D-12A-06: A Comprehensive Parameter Analysis for Low Dose Cone-Beam CT Reconstruction

    SciTech Connect (OSTI)

    Lu, W; Yan, H; Gu, X; Jiang, S; Jia, X; Bai, T; Zhou, L

    2014-06-01

    Purpose: There is always a parameter in compressive sensing based iterative reconstruction (IR) methods low dose cone-beam CT (CBCT), which controls the weight of regularization relative to data fidelity. A clear understanding of the relationship between image quality and parameter values is important. The purpose of this study is to investigate this subject based on experimental data and a representative advanced IR algorithm using Tight-frame (TF) regularization. Methods: Three data sets of a Catphan phantom acquired at low, regular and high dose levels are used. For each tests, 90 projections covering a 200-degree scan range are used for reconstruction. Three different regions-of-interest (ROIs) of different contrasts are used to calculate contrast-to-noise ratios (CNR) for contrast evaluation. A single point structure is used to measure modulation transfer function (MTF) for spatial-resolution evaluation. Finally, we analyze CNRs and MTFs to study the relationship between image quality and parameter selections. Results: It was found that: 1) there is no universal optimal parameter. The optimal parameter value depends on specific task and dose level. 2) There is a clear trade-off between CNR and resolution. The parameter for the best CNR is always smaller than that for the best resolution. 3) Optimal parameters are also dose-specific. Data acquired under a high dose protocol require less regularization, yielding smaller optimal parameter values. 4) Comparing with conventional FDK images, TF-based CBCT images are better under a certain optimally selected parameters. The advantages are more obvious for low dose data. Conclusion: We have investigated the relationship between image quality and parameter values in the TF-based IR algorithm. Preliminary results indicate optimal parameters are specific to both the task types and dose levels, providing guidance for selecting parameters in advanced IR algorithms. This work is supported in part by NIH (1R01CA154747-01)

  17. SU-E-T-86: Comparison of Two Commercially Available Programs for the Evaluation of Delivered Daily Dose Using Cone Beam CT (CBCT)

    SciTech Connect (OSTI)

    Tuohy, R; Bosse, C; Mavroidis, P; Shi, Z; Crownover, R; Papanikolaou, N; Stathakis, S

    2014-06-01

    Purpose: In this study, two commercially available programs were compared for the evaluation of delivered daily dose using cone beam CT (CBCT). Methods: Thirty (n=30) patients previously treated in our clinic (10 prostate, 10 SBRT lung and 10 abdomen) were used in this study. The patients' plans were optimized and calculated using the Pinnacle treatment planning system. The daily CBCT scans were imported into Velocity and RayStation along with the corresponding planning CTs, structure sets and 3D dose distributions for each patient. The organs at risk (OAR) were contoured on each CBCT by the prescribing physician and were included in the evaluation of the daily delivered dose. Each CBCT was registered to the planning CT, once with rigid registration and then again, separately, with deformable registration. After registering each CBCT, the dose distribution from the planning CT was overlaid and the dose volume histograms (DVH) for the OAR and the planning target volumes (PTV) were calculated. Results: For prostate patients, we observed daily volume changes for the OARs. The DVH analysis for those patients showed variation in the sparing of the OARs while PTV coverage remained virtually unchanged using both Velocity and RayStation systems. Similar results were observed for abdominal patients. In contrast, for SBRT lung patients, the DVH for the OARs and target were comparable to those from the initial treatment plan. Differences in organ volume and organ doses were also observed when comparing the daily fractions using deformable and rigid registrations. Conclusion: By using daily CBCT dose reconstruction, we proved PTV coverage for prostate and abdominal targets is adequate. However, there is significant dosimetric change for the OARs. For lung SBRT patients, the delivered daily dose for both PTV and OAR is comparable to the planned dose with no significant differences.

  18. Innovative Clean Coal Technology (ICCT): Demonstration of innovative applications of technology for cost reductions to the CT-121 FGD process. Quarterly report No. 6, July--September 1991

    SciTech Connect (OSTI)

    Not Available

    1991-11-15

    The project`s objective is to demonstrate innovative applications of technology for cost reduction for the Chiyoda Thoroughbred-121 (CT-121) process. The CT-121 process is a wet FGD process that removes SO{sub 2}, can achieve simultaneous particulate control, and can produce a salable by-product gypsum thereby reducing or even eliminating solid waste disposal problems. Figure 1 shows a flow schematic of the process. CT-121 removes SO{sub 2} and particulate matter in a unique limestone-based scrubber called the Jet Bubbling Reactor (JBR). IN the JBR, flue gas bubbles beneath the slurry, SO{sub 2} is absorbed, and particulate matter is removed from the gas. The agitator circulates limestone slurry to ensure that fresh reactant is always available in the bubbling or froth zone sot that SO{sub 2} removal can proceed at a rapid rate. Air is introduced into the bottom of the JBR to oxidize the absorbed SO{sub 2} to sulfate, and limestone is added continuously to neutralize the acid slurry and form gypsum. The JBR is designed to allow ample time for complete oxidation of the SO{sub 2}, for complete reaction of the limestone, and for growth of large gypsum crystals. The gypsum slurry is continuously withdrawn from the JBR and is to be dewatered in a gypsum stack. The stacking technique involves filing a diked area with gypsum slurry, allowing the gypsum solids to settle, and removing clear liquid from the top of the stack for recycle back to the process.

  19. TU-F-12A-04: Differential Radiation Avoidance of Functional Liver Regions Defined by 99mTc-Sulfur Colloid SPECT/CT with Proton Therapy

    SciTech Connect (OSTI)

    Bowen, S; Miyaoka, R; Kinahan, P; Sandison, G; Vesselle, H; Nyflot, M; Apisarnthanarax, S; Saini, J; Wong, T

    2014-06-15

    Purpose: Radiotherapy for hepatocellular carcinoma patients is conventionally planned without consideration of spatial heterogeneity in hepatic function, which may increase risk of radiation-induced liver disease. Pencil beam scanning (PBS) proton radiotherapy (pRT) plans were generated to differentially decrease dose to functional liver volumes (FLV) defined on [{sup 99m}Tc]sulfur colloid (SC) SPECT/CT images (functional avoidance plans) and compared against conventional pRT plans. Methods: Three HCC patients underwent SC SPECT/CT scans for pRT planning acquired 15 min post injection over 24 min. Images were reconstructed with OSEM following scatter, collimator, and exhale CT attenuation correction. Functional liver volumes (FLV) were defined by liver:spleen uptake ratio thresholds (43% to 90% maximum). Planning objectives to FLV were based on mean SC SPECT uptake ratio relative to GTV-subtracted liver and inversely scaled to mean liver dose of 20 Gy. PTV target coverage (V{sub 95}) was matched between conventional and functional avoidance plans. PBS pRT plans were optimized in RayStation for single field uniform dose (SFUD) and systematically perturbed to verify robustness to uncertainty in range, setup, and motion. Relative differences in FLV DVH and target dose heterogeneity (D{sub 2}-D{sub 98})/D50 were assessed. Results: For similar liver dose between functional avoidance and conventional PBS pRT plans (D{sub mean}?5% difference, V{sub 18Gy}?1% difference), dose to functional liver volumes were lower in avoidance plans but varied in magnitude across patients (FLV{sub 70%max} D{sub mean}?26% difference, V{sub 18Gy}?8% difference). Higher PTV dose heterogeneity in avoidance plans was associated with lower functional liver dose, particularly for the largest lesion [(D{sub 2}-D{sub 98})/D{sub 50}=13%, FLV{sub 90%max}=50% difference]. Conclusion: Differential avoidance of functional liver regions defined on sulfur colloid SPECT/CT is feasible with proton therapy. The magnitude of benefit appears to be patient specific and dependent on tumor location, size, and proximity to functional volumes. Further investigation in a larger cohort of patients may validate the clinical utility of functional avoidance planning of HCC radiotherapy.

  20. Pilot study for compact microbeam radiation therapy using a carbon nanotube field emission micro-CT scanner

    SciTech Connect (OSTI)

    Hadsell, Mike Cao, Guohua; Zhang, Jian; Burk, Laurel; Schreiber, Torsten; Lu, Jianping; Zhou, Otto; Schreiber, Eric; Chang, Sha

    2014-06-15

    Purpose: Microbeam radiation therapy (MRT) is defined as the use of parallel, microplanar x-ray beams with an energy spectrum between 50 and 300 keV for cancer treatment and brain radiosurgery. Up until now, the possibilities of MRT have mainly been studied using synchrotron sources due to their high flux (100s Gy/s) and approximately parallel x-ray paths. The authors have proposed a compact x-ray based MRT system capable of delivering MRT dose distributions at a high dose rate. This system would employ carbon nanotube (CNT) field emission technology to create an x-ray source array that surrounds the target of irradiation. Using such a geometry, multiple collimators would shape the irradiation from this array into multiple microbeams that would then overlap or interlace in the target region. This pilot study demonstrates the feasibility of attaining a high dose rate and parallel microbeam beams using such a system. Methods: The microbeam dose distribution was generated by our CNT micro-CT scanner (100?m focal spot) and a custom-made microbeam collimator. An alignment assembly was fabricated and attached to the scanner in order to collimate and superimpose beams coming from different gantry positions. The MRT dose distribution was measured using two orthogonal radiochromic films embedded inside a cylindrical phantom. This target was irradiated with microbeams incident from 44 different gantry angles to simulate an array of x-ray sources as in the proposed compact CNT-based MRT system. Finally, phantom translation in a direction perpendicular to the microplanar beams was used to simulate the use of multiple parallel microbeams. Results: Microbeams delivered from 44 gantry angles were superimposed to form a single microbeam dose distribution in the phantom with a FWHM of 300?m (calculated value was 290 ?m). Also, during the multiple beam simulation, a peak to valley dose ratio of ?10 was found when the phantom translation distance was roughly 4x the beam width. The first prototype CNT-based x-ray tube dedicated to the development of compact MRT technology development was proposed and planned based on the preliminary experimental results presented here and the previous corresponding Monte Carlo simulations. Conclusions: The authors have demonstrated the feasibility of creating microbeam dose distributions at a high dose rate using a proposed compact MRT system. The flexibility of CNT field emission x-ray sources could possibly bring compact and low cost MRT devices to the larger research community and assist in the translational research of this promising new approach to radiation therapy.

  1. Liver segmentation in contrast enhanced CT data using graph cuts and interactive 3D segmentation refinement methods

    SciTech Connect (OSTI)

    Beichel, Reinhard; Bornik, Alexander; Bauer, Christian; Sorantin, Erich [Departments of Electrical and Computer Engineering and Internal Medicine, Iowa Institute for Biomedical Imaging, University of Iowa, Iowa City, Iowa 52242 (United States); Institute for Computer Graphics and Vision, Graz University of Technology, Inffeldgasse 16, A-8010 Graz (Austria); Department of Electrical and Computer Engineering, Iowa Institute for Biomedical Imaging, University of Iowa, Iowa City, Iowa 52242 (United States); Department of Radiology, Medical University Graz, Auenbruggerplatz 34, A-8010 Graz (Austria)

    2012-03-15

    Purpose: Liver segmentation is an important prerequisite for the assessment of liver cancer treatment options like tumor resection, image-guided radiation therapy (IGRT), radiofrequency ablation, etc. The purpose of this work was to evaluate a new approach for liver segmentation. Methods: A graph cuts segmentation method was combined with a three-dimensional virtual reality based segmentation refinement approach. The developed interactive segmentation system allowed the user to manipulate volume chunks and/or surfaces instead of 2D contours in cross-sectional images (i.e, slice-by-slice). The method was evaluated on twenty routinely acquired portal-phase contrast enhanced multislice computed tomography (CT) data sets. An independent reference was generated by utilizing a currently clinically utilized slice-by-slice segmentation method. After 1 h of introduction to the developed segmentation system, three experts were asked to segment all twenty data sets with the proposed method. Results: Compared to the independent standard, the relative volumetric segmentation overlap error averaged over all three experts and all twenty data sets was 3.74%. Liver segmentation required on average 16 min of user interaction per case. The calculated relative volumetric overlap errors were not found to be significantly different [analysis of variance (ANOVA) test, p = 0.82] between experts who utilized the proposed 3D system. In contrast, the time required by each expert for segmentation was found to be significantly different (ANOVA test, p = 0.0009). Major differences between generated segmentations and independent references were observed in areas were vessels enter or leave the liver and no accepted criteria for defining liver boundaries exist. In comparison, slice-by-slice based generation of the independent standard utilizing a live wire tool took 70.1 min on average. A standard 2D segmentation refinement approach applied to all twenty data sets required on average 38.2 min of user interaction and resulted in statistically not significantly different segmentation error indices (ANOVA test, significance level of 0.05). Conclusions: All three experts were able to produce liver segmentations with low error rates. User interaction time savings of up to 71% compared to a 2D refinement approach demonstrate the utility and potential of our approach. The system offers a range of different tools to manipulate segmentation results, and some users might benefit from a longer learning phase to develop efficient segmentation refinement strategies. The presented approach represents a generally applicable segmentation approach that can be applied to many medical image segmentation problems.

  2. CT Clean Energy Communities

    Broader source: Energy.gov [DOE]

    The Clean Energy Communities program, offered by the Clean Energy Finance & Investment Authority and the Connecticut Energy Efficiency Fund, offers incentives for communities that pledge their...

  3. ContaCt

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room News PublicationsAuditsCluster Compatibilitydefaultin[NiFe]-hydrogenase models:

  4. Dual-energy cone-beam CT with a flat-panel detector: Effect of reconstruction algorithm on material classification

    SciTech Connect (OSTI)

    Zbijewski, W., E-mail: wzbijewski@jhu.edu; Gang, G. J.; Xu, J.; Wang, A. S.; Stayman, J. W. [Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21205 (United States)] [Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21205 (United States); Taguchi, K.; Carrino, J. A. [Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, Maryland 21205 (United States)] [Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, Maryland 21205 (United States); Siewerdsen, J. H. [Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21205 and Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, Maryland 21205 (United States)] [Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21205 and Russell H. Morgan Department of Radiology, Johns Hopkins University, Baltimore, Maryland 21205 (United States)

    2014-02-15

    Purpose: Cone-beam CT (CBCT) with a flat-panel detector (FPD) is finding application in areas such as breast and musculoskeletal imaging, where dual-energy (DE) capabilities offer potential benefit. The authors investigate the accuracy of material classification in DE CBCT using filtered backprojection (FBP) and penalized likelihood (PL) reconstruction and optimize contrast-enhanced DE CBCT of the joints as a function of dose, material concentration, and detail size. Methods: Phantoms consisting of a 15 cm diameter water cylinder with solid calcium inserts (50–200 mg/ml, 3–28.4 mm diameter) and solid iodine inserts (2–10 mg/ml, 3–28.4 mm diameter), as well as a cadaveric knee with intra-articular injection of iodine were imaged on a CBCT bench with a Varian 4343 FPD. The low energy (LE) beam was 70 kVp (+0.2 mm Cu), and the high energy (HE) beam was 120 kVp (+0.2 mm Cu, +0.5 mm Ag). Total dose (LE+HE) was varied from 3.1 to 15.6 mGy with equal dose allocation. Image-based DE classification involved a nearest distance classifier in the space of LE versus HE attenuation values. Recognizing the differences in noise between LE and HE beams, the LE and HE data were differentially filtered (in FBP) or regularized (in PL). Both a quadratic (PLQ) and a total-variation penalty (PLTV) were investigated for PL. The performance of DE CBCT material discrimination was quantified in terms of voxelwise specificity, sensitivity, and accuracy. Results: Noise in the HE image was primarily responsible for classification errors within the contrast inserts, whereas noise in the LE image mainly influenced classification in the surrounding water. For inserts of diameter 28.4 mm, DE CBCT reconstructions were optimized to maximize the total combined accuracy across the range of calcium and iodine concentrations, yielding values of ?88% for FBP and PLQ, and ?95% for PLTV at 3.1 mGy total dose, increasing to ?95% for FBP and PLQ, and ?98% for PLTV at 15.6 mGy total dose. For a fixed iodine concentration of 5 mg/ml and reconstructions maximizing overall accuracy across the range of insert diameters, the minimum diameter classified with accuracy >80% was ?15 mm for FBP and PLQ and ?10 mm for PLTV, improving to ?7 mm for FBP and PLQ and ?3 mm for PLTV at 15.6 mGy. The results indicate similar performance for FBP and PLQ and showed improved classification accuracy with edge-preserving PLTV. A slight preference for increased smoothing of the HE data was found. DE CBCT discrimination of iodine and bone in the knee was demonstrated with FBP and PLTV at 6.2 mGy total dose. Conclusions: For iodine concentrations >5 mg/ml and detail size ?20 mm, material classification accuracy of >90% was achieved in DE CBCT with both FBP and PL at total doses <10 mGy. Optimal performance was attained by selection of reconstruction parameters based on the differences in noise between HE and LE data, typically favoring stronger smoothing of the HE data, and by using penalties matched to the imaging task (e.g., edge-preserving PLTV in areas of uniform enhancement)

  5. Assessment of dedicated low-dose cardiac micro-CT reconstruction algorithms using the left ventricular volume of small rodents as a performance measure

    SciTech Connect (OSTI)

    Maier, Joscha; Sawall, Stefan; Kachelrieß, Marc

    2014-05-15

    Purpose: Phase-correlated microcomputed tomography (micro-CT) imaging plays an important role in the assessment of mouse models of cardiovascular diseases and the determination of functional parameters as the left ventricular volume. As the current gold standard, the phase-correlated Feldkamp reconstruction (PCF), shows poor performance in case of low dose scans, more sophisticated reconstruction algorithms have been proposed to enable low-dose imaging. In this study, the authors focus on the McKinnon-Bates (MKB) algorithm, the low dose phase-correlated (LDPC) reconstruction, and the high-dimensional total variation minimization reconstruction (HDTV) and investigate their potential to accurately determine the left ventricular volume at different dose levels from 50 to 500 mGy. The results were verified in phantom studies of a five-dimensional (5D) mathematical mouse phantom. Methods: Micro-CT data of eight mice, each administered with an x-ray dose of 500 mGy, were acquired, retrospectively gated for cardiac and respiratory motion and reconstructed using PCF, MKB, LDPC, and HDTV. Dose levels down to 50 mGy were simulated by using only a fraction of the projections. Contrast-to-noise ratio (CNR) was evaluated as a measure of image quality. Left ventricular volume was determined using different segmentation algorithms (Otsu, level sets, region growing). Forward projections of the 5D mouse phantom were performed to simulate a micro-CT scan. The simulated data were processed the same way as the real mouse data sets. Results: Compared to the conventional PCF reconstruction, the MKB, LDPC, and HDTV algorithm yield images of increased quality in terms of CNR. While the MKB reconstruction only provides small improvements, a significant increase of the CNR is observed in LDPC and HDTV reconstructions. The phantom studies demonstrate that left ventricular volumes can be determined accurately at 500 mGy. For lower dose levels which were simulated for real mouse data sets, the HDTV algorithm shows the best performance. At 50 mGy, the deviation from the reference obtained at 500 mGy were less than 4%. Also the LDPC algorithm provides reasonable results with deviation less than 10% at 50 mGy while PCF and MKB reconstruction show larger deviations even at higher dose levels. Conclusions: LDPC and HDTV increase CNR and allow for quantitative evaluations even at dose levels as low as 50 mGy. The left ventricular volumes exemplarily illustrate that cardiac parameters can be accurately estimated at lowest dose levels if sophisticated algorithms are used. This allows to reduce dose by a factor of 10 compared to today's gold standard and opens new options for longitudinal studies of the heart.

  6. SU-E-I-46: Sample-Size Dependence of Model Observers for Estimating Low-Contrast Detection Performance From CT Images

    SciTech Connect (OSTI)

    Reiser, I; Lu, Z [University of Chicago, Chicago, IL (United States)

    2014-06-01

    Purpose: Recently, task-based assessment of diagnostic CT systems has attracted much attention. Detection task performance can be estimated using human observers, or mathematical observer models. While most models are well established, considerable bias can be introduced when performance is estimated from a limited number of image samples. Thus, the purpose of this work was to assess the effect of sample size on bias and uncertainty of two channelized Hotelling observers and a template-matching observer. Methods: The image data used for this study consisted of 100 signal-present and 100 signal-absent regions-of-interest, which were extracted from CT slices. The experimental conditions included two signal sizes and five different x-ray beam current settings (mAs). Human observer performance for these images was determined in 2-alternative forced choice experiments. These data were provided by the Mayo clinic in Rochester, MN. Detection performance was estimated from three observer models, including channelized Hotelling observers (CHO) with Gabor or Laguerre-Gauss (LG) channels, and a template-matching observer (TM). Different sample sizes were generated by randomly selecting a subset of image pairs, (N=20,40,60,80). Observer performance was quantified as proportion of correct responses (PC). Bias was quantified as the relative difference of PC for 20 and 80 image pairs. Results: For n=100, all observer models predicted human performance across mAs and signal sizes. Bias was 23% for CHO (Gabor), 7% for CHO (LG), and 3% for TM. The relative standard deviation, ?(PC)/PC at N=20 was highest for the TM observer (11%) and lowest for the CHO (Gabor) observer (5%). Conclusion: In order to make image quality assessment feasible in the clinical practice, a statistically efficient observer model, that can predict performance from few samples, is needed. Our results identified two observer models that may be suited for this task.

  7. SU-E-J-103: Setup Errors Analysis by Cone-Beam CT (CBCT)-Based Imaged-Guided Intensity Modulated Radiotherapy for Esophageal Cancer

    SciTech Connect (OSTI)

    Yang, H; Wang, W; Hu, W; Chen, X; Wang, X; Yu, C [Taizhou Hospital, Wenzhou Medical College, Taizhou, Zhejiang (China)

    2014-06-01

    Purpose: To quantify setup errors by pretreatment kilovolt cone-beam computed tomography(KV-CBCT) scans for middle or distal esophageal carcinoma patients. Methods: Fifty-two consecutive middle or distal esophageal carcinoma patients who underwent IMRT were included this study. A planning CT scan using a big-bore CT simulator was performed in the treatment position and was used as the reference scan for image registration with CBCT. CBCT scans(On-Board Imaging v1. 5 system, Varian Medical Systems) were acquired daily during the first treatment week. A total of 260 CBCT scans was assessed with a registration clip box defined around the PTV-thorax in the reference scan based on(nine CBCTs per patient) bony anatomy using Offline Review software v10.0(Varian Medical Systems). The anterior-posterior(AP), left-right(LR), superiorinferior( SI) corrections were recorded. The systematic and random errors were calculated. The CTV-to-PTV margins in each CBCT frequency was based on the Van Herk formula (2.5?+0.7?). Results: The SD of systematic error (?) was 2.0mm, 2.3mm, 3.8mm in the AP, LR and SI directions, respectively. The average random error (?) was 1.6mm, 2.4mm, 4.1mm in the AP, LR and SI directions, respectively. The CTV-to-PTV safety margin was 6.1mm, 7.5mm, 12.3mm in the AP, LR and SI directions based on van Herk formula. Conclusion: Our data recommend the use of 6 mm, 8mm, and 12 mm for esophageal carcinoma patient setup in AP, LR, SI directions, respectively.

  8. A Signal Processing Model of a Product Development Process Phase

    E-Print Network [OSTI]

    Ford, David N.

    Variables: CTi = CTi0 + 0 T (BWi + RWi - IFi - RTi) dt where #12;i = development phase T = time, weeks CT week RW = Rework rate, tasks per week TRi = TRi0 + 0 T RTi dt where TR = Tasks Released, tasks RT, dimensionless #12;CT = Completed, not Checked stock, tasks QADur = Quality Assurance Minimum Duration, week RTi

  9. SU-E-I-89: Assessment of CT Radiation Dose and Image Quality for An Automated Tube Potential Selection Algorithm Using Pediatric Anthropomorphic and ACR Phantoms

    SciTech Connect (OSTI)

    Mahmood, U; Erdi, Y; Wang, W

    2014-06-01

    Purpose: To assess the impact of General Electrics automated tube potential algorithm, kV assist (kVa) on radiation dose and image quality, with an emphasis on optimizing protocols based on noise texture. Methods: Radiation dose was assessed by inserting optically stimulated luminescence dosimeters (OSLs) throughout the body of a pediatric anthropomorphic phantom (CIRS). The baseline protocol was: 120 kVp, 80 mA, 0.7s rotation time. Image quality was assessed by calculating the contrast to noise ratio (CNR) and noise power spectrum (NPS) from the ACR CT accreditation phantom. CNRs were calculated according to the steps described in ACR CT phantom testing document. NPS was determined by taking the 3D FFT of the uniformity section of the ACR phantom. NPS and CNR were evaluated with and without kVa and for all available adaptive iterative statistical reconstruction (ASiR) settings, ranging from 0 to 100%. Each NPS was also evaluated for its peak frequency difference (PFD) with respect to the baseline protocol. Results: For the baseline protocol, CNR was found to decrease from 0.460 ± 0.182 to 0.420 ± 0.057 when kVa was activated. When compared against the baseline protocol, the PFD at ASiR of 40% yielded a decrease in noise magnitude as realized by the increase in CNR = 0.620 ± 0.040. The liver dose decreased by 30% with kVa activation. Conclusion: Application of kVa reduces the liver dose up to 30%. However, reduction in image quality for abdominal scans occurs when using the automated tube voltage selection feature at the baseline protocol. As demonstrated by the CNR and NPS analysis, the texture and magnitude of the noise in reconstructed images at ASiR 40% was found to be the same as our baseline images. We have demonstrated that 30% dose reduction is possible when using 40% ASiR with kVa in pediatric patients.

  10. SU-E-I-81: Assessment of CT Radiation Dose and Image Quality for An Automated Tube Potential Selection Algorithm Using Adult Anthropomorphic and ACR Phantoms

    SciTech Connect (OSTI)

    Mahmood, U; Erdi, Y; Wang, W

    2014-06-01

    Purpose: To assess the impact of General Electrics (GE) automated tube potential algorithm, kV assist (kVa) on radiation dose and image quality, with an emphasis on optimizing protocols based on noise texture. Methods: Radiation dose was assessed by inserting optically stimulated luminescence dosimeters (OSLs) throughout the body of an adult anthropomorphic phantom (CIRS). The baseline protocol was: 120 kVp, Auto mA (180 to 380 mA), noise index (NI) = 14, adaptive iterative statistical reconstruction (ASiR) of 20%, 0.8s rotation time. Image quality was evaluated by calculating the contrast to noise ratio (CNR) and noise power spectrum (NPS) from the ACR CT accreditation phantom. CNRs were calculated according to the steps described in ACR CT phantom testing document. NPS was determined by taking the 3D FFT of the uniformity section of the ACR phantom. NPS and CNR were evaluated with and without kVa and for all available adaptive iterative statistical reconstruction (ASiR) settings, ranging from 0 to 100%. Each NPS was also evaluated for its peak frequency difference (PFD) with respect to the baseline protocol. Results: The CNR for the adult male was found to decrease from CNR = 0.912 ± 0.045 for the baseline protocol without kVa to a CNR = 0.756 ± 0.049 with kVa activated. When compared against the baseline protocol, the PFD at ASiR of 40% yielded a decrease in noise magnitude as realized by the increase in CNR = 0.903 ± 0.023. The difference in the central liver dose with and without kVa was found to be 0.07%. Conclusion: Dose reduction was insignificant in the adult phantom. As determined by NPS analysis, ASiR of 40% produced images with similar noise texture to the baseline protocol. However, the CNR at ASiR of 40% with kVa fails to meet the current ACR CNR passing requirement of 1.0.

  11. 3D inpatient dose reconstruction from the PET-CT imaging of {sup 90}Y microspheres for metastatic cancer to the liver: Feasibility study

    SciTech Connect (OSTI)

    Fourkal, E.; Veltchev, I.; Lin, M.; Meyer, J.; Koren, S.; Doss, M.; Yu, J. Q.

    2013-08-15

    Purpose: The introduction of radioembolization with microspheres represents a significant step forward in the treatment of patients with metastatic disease to the liver. This technique uses semiempirical formulae based on body surface area or liver and target volumes to calculate the required total activity for a given patient. However, this treatment modality lacks extremely important information, which is the three-dimensional (3D) dose delivered by microspheres to different organs after their administration. The absence of this information dramatically limits the clinical efficacy of this modality, specifically the predictive power of the treatment. Therefore, the aim of this study is to develop a 3D dose calculation technique that is based on the PET imaging of the infused microspheres.Methods: The Fluka Monte Carlo code was used to calculate the voxel dose kernel for {sup 90}Y source with voxel size equal to that of the PET scan. The measured PET activity distribution was converted to total activity distribution for the subsequent convolution with the voxel dose kernel to obtain the 3D dose distribution. In addition, dose-volume histograms were generated to analyze the dose to the tumor and critical structures.Results: The 3D inpatient dose distribution can be reconstructed from the PET data of a patient scanned after the infusion of microspheres. A total of seven patients have been analyzed so far using the proposed reconstruction method. Four patients underwent treatment with SIR-Spheres for liver metastases from colorectal cancer and three patients were treated with Therasphere for hepatocellular cancer. A total of 14 target tumors were contoured on post-treatment PET-CT scans for dosimetric evaluation. Mean prescription activity was 1.7 GBq (range: 0.58–3.8 GBq). The resulting mean maximum measured dose to targets was 167 Gy (range: 71–311 Gy). Mean minimum dose to 70% of target (D70) was 68 Gy (range: 25–155 Gy). Mean minimum dose to 90% of target (D90) was 53 Gy (range: 13–125 Gy).Conclusions: A three-dimensional inpatient dose reconstruction method has been developed that is based on the PET/CT data of a patient treated with {sup 90}Y microspheres. It allows for a complete description of the absorbed dose by the tumor and critical structures. It represents the first step in building predictive models for treatment outcomes for patients receiving this therapeutic modality as well as it allows for better analysis of patients' dose response and will ultimately improve future treatment administration.

  12. Human Dosimetry and Preliminary Tumor Distribution of (superscript)18F-Fluoropaclitaxel in Healthy Volunteers and Newly Diagnosed Breast Cancer Patients Using PET/CT

    SciTech Connect (OSTI)

    Kurdziel, K.A.; Logan, J.; Kurdziel, K.A.; Kalen, J.D.; Hirsch, J.I.; Wilson, J.D.; Bear, H.D.; Logan, J.; McCumisky, J.; Moorman-Sykes, K.; Adler, S.; Choyke, P.L.

    2011-08-17

    {sup 18}F-fluoropaclitaxel is a radiolabeled form of paclitaxel, a widely used chemotherapy agent. Preclinical data suggest that {sup 18}F-fluoropaclitaxel may be a reasonable surrogate for measuring the uptake of paclitaxel. As a substrate of P-glycoprotein, a drug efflux pump associated with multidrug resistance, {sup 18}F-fluoropaclitaxel may also be useful in identifying multidrug resistance and predicting tumor response for drugs other than paclitaxel. After informed consent was obtained, 3 healthy volunteers and 3 patients with untreated breast cancer (neoadjuvant chemotherapy candidates, tumor size > 2 cm) received an intravenous infusion of {sup 18}F-fluoropaclitaxel and then underwent PET/CT. Healthy volunteers underwent serial whole-body imaging over an approximately 3-h interval, and organ {sup 18}F residence times were determined from the time-activity curves uncorrected for decay to determine dosimetry. Radiation dose estimates were calculated using OLINDA/EXM software. For breast cancer patients, dynamic imaging of the primary tumor was performed for 60 min, followed by static whole-body scans at 1 and 2 h after injection. Dosimetry calculations showed that the gallbladder received the highest dose (229.50 {mu}Gy/MBq [0.849 rad/mCi]), followed by the small and large intestines (161.26 {mu}Gy/MBq [0.597 rad/mCi] and 184.59 {mu}Gy/MBq [0.683 rad/mCi]). The resultant effective dose was 28.79 {mu}Gy/MBq (0.107 rem/mCi). At approximately 1 h after injection, an average of 42% of the decay-corrected activity was in the gastrointestinal system, with a mean of 0.01% in the tumor. All 3 breast cancer patients showed retention of {sup 18}F-fluoropaclitaxel and ultimately demonstrated a complete pathologic response (no invasive cancer in the breast or axillary nodes) to chemotherapy that included a taxane (either paclitaxel or docetaxel) at surgical resection. The tumor-to-background ratio increased with time to a maximum of 7.7 at 20 min. This study demonstrates the feasibility of using {sup 18}F-fluoropaclitaxel PET/CT tumor imaging and provides radiation dosimetry measurements in humans. Although further study is needed, it is hoped that the measured intratumoral {sup 18}F-fluoropaclitaxel distribution can serve as a surrogate for paclitaxel, and potentially other chemotherapeutic agent retention, in solid tumors.

  13. TRI-PARTY AGREEMENT OPERABLE UNITS PROJECT MANAGERS LIST AS...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    By MSA TPA Site Wide Integration Name EPA PM Ecology PM DOE PM Assistant Manager Lead Regulatory Agency (See Footnote) Unit Description 100-BC-1 Buelow, L.C. Menard, N....

  14. Tri State Generation and Transmission Association Inc | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEt Al., 2013)OpenEnergyTrail CanyonsourceRiver Solar |Trexa Motor

  15. Tri-State Electric Member Corp (Tennessee) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEt Al., 2013)OpenEnergyTrail CanyonsourceRiver Solar |Trexa

  16. The Value of Green Tri-City Speaker Series

    E-Print Network [OSTI]

    in response to shareholder concerns and future carbon-related risks ­ Incorporation of climate risk Has Been Made But a lot of work still remains to be done LEED certified projects now account for 6

  17. Emotionally Contentious Social Movements: A Tri-Variate Framework

    E-Print Network [OSTI]

    Sin, Ray

    2009-01-01

    After decades of seeing emotions as irrational and unimportant, scholars in social movements are beginning to value the role of emotions in social movements. This paper contributes to the burgeoning literature on emotions and contentious politics...

  18. PECIAL REPORS T Tri-County Health Department

    E-Print Network [OSTI]

    , local EH officials limit their comments to regulatory requirements for air and water quality, waste, but are not subject to regulatory requirements. Discretionary comments make up the bulk of TCHD's input. This is due that the built environment can en courage or discourage physical activity, a criti cal public health challenge

  19. Faculty Council on Tri-campus Policy Annual Report

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    of the Faculty Code to formalize faculty governance and curricular practices on UW Bothell and UW Tacoma campuses (TIAS-20050726D) Environmental Studies (TIAS-20050726E) Ethnic, Gender, and Labor Studies (TIAS-20050726F) General Studies (TIAS-20050726G) Global Studies (TIAS-20050726H) Individualized-designed Major

  20. Characterization of the Tri10 gene from Fusarium sporotrichioides 

    E-Print Network [OSTI]

    Tag, Andrew George

    2004-09-30

    The trichothecene mycotoxins are secondary metabolites produced by a variety of fungal genera including Fusarium, Myrothecium, Trichothecium, and Stachybotyris, that are toxic to humans and animals that ingest them by ...

  1. Process for selective production of di- and tri-alkylamines

    DOE Patents [OSTI]

    Klier, Kamil (Bethlehem, PA); Herman, Richard G. (Whitehall, PA); Vedage, Gamini A. (Bethlehem, PA)

    1984-01-01

    A primary alkyl amine and an alcohol of up to 12 carbon atoms are reacted at low temperature (50.degree.-250.degree. C.) over specific catalysts (alkali-treated catalysts generally or binary Cu/ZnO and Pd/SiO.sub.2 systems, with or without alkali treatment) to produce, with good selectivity, secondary and tertiary alkylamines of the general formula, R.sub.1 N(R.sub.2).sub.2, wherein R.sub.1 is a lower alkyl or an aryl group, and R.sub.2 is hydrogen or another lower alkyl or aryl group, with at least one of R.sub.2 's being an alkyl or aryl group.

  2. New Guatemala law tries to attract new explorers

    SciTech Connect (OSTI)

    Not Available

    1984-02-01

    With only 6,280 bopd of production and reserves of only 13 million barrels, Guatemala's 25,200 bpd thirst has forced the country to rewrite its petroleum law. Among pluses in the new law are full-cost recovery and prices based on world levels. However, the stiff royalty and no provision for neutral arbitration are significant minuses.

  3. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    has received equally positive feedback from faculty at UW Tacoma. And Don Whitney said the PSO for UW Tacoma, there is "Review and approval by faculty associated with RAPP (Review and Approval Viability." In the third review process for UW Tacoma, there is "Review and approval of courses through

  4. University of Washington Faculty Council on Tri-Campus Policy

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    two items: · He sat in on interviews for the UW Tacoma chancellor search. Deborah Friedman has been. Moves that Seattle makes have implications for Tacoma and Bothell; likewise, moves each campus makes, Associate Director of Student Services, UW Tacoma, joined the council for a discussion of issues related

  5. UNIVERSITY OF WASHINGTON FACULTY COUNCIL TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    [March 4, 1996, UW, Tacoma] by Sue Thomas Hegyvary, Dean and Professor, University of Washington School. Meszaros indicated that the Tacoma Faculty were not able to prepare for such a discussion in the last couple of weeks. Crawford clarified that UW Tacoma's Faculty Assembly Executive Committee did not inten

  6. University of Washington Faculty Council on Tri-Campus Policy

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    that UW Bothell and Tacoma were prominently displayed. Faculty demographics created a great deal to the hiring of lecturers compared to tenure-track faculty. Harrington noted that UW-Tacoma once relied on lecturer appointments early on as the campus began to grow. Currently, UW-Tacoma is working to reduce

  7. University Of Washington Faculty Council on Tri-Campus Policy

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    regarding Diversity within the Promotion and Tenure guidelines. Vice Chancellor of UW Tacoma's Academic and Tacoma campuses. Though Bothell and Tacoma manage their own admissions and administrative policy, faculty current policy, short and long-terms changes and the involvement of Bothell or Tacoma administration

  8. UNIVERSITY OF WASHINGTON FACULTY COUNCIL TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    met at 9:30 a.m. on Monday, December 17, 2001, in The Tacoma Room at UW Tacoma. Chair Jacqueline Tacoma: Chair, Committee on Admissions, Academic Standards and Graduation ABSENT: Professors Leppa of the November 19, 2001 meeting were approved as amended. Discussion of proposed UW Tacoma Honors ­ Robert

  9. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    as the Tacoma representative for Johann Reusch, vice chair of the Faculty Assembly, who could not make today meetings (2 hours each). The December meeting will be held at the Tacoma campus. Council members were it is working. She said they might consider a spring poll of advisors. Representation of UW-Tacoma and UW

  10. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    's Office, UW, Tacoma (for Jack Nelson). ABSENT: Professor Anderson; Ex officio members Campbell, Heath at the Bothell or Tacoma campus". In 13-23. E., the addition of the words "that are campus-specific to UW, Tacoma and UW, Bothell] have been asked to work together to create a vision statement on the relationship

  11. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    at UW Bothell and UW Tacoma." Olswang said, "The law states that all faculty are under one unit. We can Tacoma. Second, it might make it harder for us to recruit good people. We are already a bit of a tough on unionization. I believe people might feel more protected if UW Bothell and UW Tacoma did have unions." Meszaros

  12. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    legislation With respect to the academic honors for outstanding transfer students at UW Seattle, UW Tacoma, and UW Bothell, it was observed that both the Tacoma and Bothell campuses are considering Chancellors Tacoma has finalized their decision on this. Meszaros said there will be a meeting at UW Bothell

  13. University of Washington Faculty Council on Tri-Campus Policy

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    programs on UWB program offerings 3. Form 1503 comments 4. Tacoma and Bothell representation on faculty extends back several years and relates to the relationship between the Seattle campus and Tacoma that relates mainly to Bothell, but may affect Tacoma as well." Since a large proportion of UWB's applicants

  14. University of Washington Faculty Council on Tri-Campus Policy

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    ;2 Organization (GFO) operates parallel to the Faculty Senate and suggested that a UW Seattle and/or Tacoma with UW Bothell GFO and/or the UW Tacoma Faculty Assembly (FA) sometime this year. Erdly suggested search for a new UW Tacoma chancellor this may be the opportunity to discuss how the administration

  15. UNIVERSITY OF WASHINGTON FACULTY COUNCIL TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    noted that the UW Bothell and UW Tacoma campuses opened a decade ago. Faculty from the Seattle campus the issue "that we were all governed by the same Faculty Code, but that UW Bothell and UW Tacoma had weak and Tacoma campuses." Crawford said there had been an earlier joint faculty council. That council had

  16. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    the Faculty Senate again at its May meeting. Olswang pointed out that the UW, Tacoma and the UW, Bothell, Tacoma, if the relevant section does not explicitly refer to the UW, Bothell, the UW, Tacoma, campus

  17. University of Washington Faculty Council on Tri-Campus Policy

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    the Chair Erdly noted the UW Bothell and Tacoma campuses are beginning to celebrate their 25 year anniversaries. He explained the breadth and number of degree options at the Bothell and Tacoma campuses have Tacoma, will bring some shifts to the campus. He then urged the council to consider their own questions

  18. University Of Washington Faculty Council on Tri-Campus Policy

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    planning. e) Discussion of potential issues related to UW Seattle, Bothell and Tacoma self of variations/changes to faculty handbook that affect UW Tacoma and Bothell faculty: Erdly informed that he has received questions on variations between practice and policies within the faculty handbook at UW Tacoma

  19. UNIVERSITY OF WASHINGTON FACULTY COUNCIL TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    to questions of interdependence and independence at UW Seattle, UW Bothell and UW Tacoma, Friedman said campuses." She noted that there are many "committed, dynamic faculty" at the Bothell and Tacoma campuses, just as there are at the Seattle campus. "The foundation at UW Bothell and UW Tacoma is strong

  20. University of Washington Faculty Council on Tri-Campus Policy

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    the Bothell and Tacoma campuses at the same meeting, and what subjects to discuss at the Senate meeting that the Senate meeting should include both Bothell and Tacoma, that a focus should be faculty-to-faculty sharing shared with the UW-Tacoma campus b

  1. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    to the chancellors at UW Tacoma and UW Bothell. At the same time, the president also sent it to the chancellors, but not directly to faculty heads at UW Tacoma and UW Bothell. In January, I contacted heads of faculty organizations at UW Bothell and UW Tacoma, and asked if their curriculum review bodies had received

  2. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS POLICY

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    Assembly, UW Tacoma; Josh Tenenberg, Vice Chair, Faculty Assembly, UW Tacoma; Susan Jeffords, Vice Provost Chair, who would send the proposal back to the President and to the Chancellors of UW Tacoma and UW Seattle, General Faculty Organization at UW Bothell, or Faculty Assembly at UW Tacoma) receives a proposal

  3. Tri-axial Octupole Deformations and Shell Structure

    E-Print Network [OSTI]

    W. D. Heiss; R. G. Nazmitdinov; R. A. Lynch

    1999-04-28

    Manifestations of pronounced shell effects are discovered when adding nonaxial octupole deformations to a harmonic oscillator model. The degeneracies of the quantum spectra are in a good agreement with the corresponding main periodic orbits and winding number ratios which are found by classical analysis.

  4. UNIVERSITY OF WASHINGTON FACULTY COUNCIL ON TRI-CAMPUS RELATIONS

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    by Alex Bolton Council Support Analyst bolt@u.washington.edu Present: Faculty: Collins (Chair), Wood

  5. A Heart of Gold? Try Platinum | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    collaboration with researchers at Boston Scientific Corporation. The alloy is the first stainless steel formulation for stents with a significant concentration of platinum,...

  6. DOE - Office of Legacy Management -- Try Street Terminal - PA 14

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth DakotaRobbins and Myers Co - OHStarTracerlab Inc - MA 11USTry

  7. Tri-Lab Directors' statement on the nuclear posture review

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout / TransformingTransuranic Waste RetrievalTrending:

  8. Name: Lisa Anderson Organization: Tri-City Railroad Company

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass map shines lightGeospatialDevelopment of09 AugustPlasmaResearchersStudyThe9085023

  9. Hawkeye Tri-County El Coop Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar2-0057-EA JumpDuimen River Power CoHawaii/Incentives < Hawaii Jump

  10. Tri State Electric Membership Corporation Smart Grid Project | Open Energy

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems Inc Jump

  11. Tri-County Elec Member Corp | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems Inc JumpNorthCounty

  12. Tri-County Electric Coop (Michigan) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems Inc

  13. Tri-County Electric Coop Assn | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems IncAssn Jump to:

  14. Tri-County Electric Coop | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems IncAssn Jump

  15. Tri-County Electric Coop, Inc (Florida) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems IncAssn JumpFlorida)

  16. Tri-County Electric Coop, Inc (Illinois) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems IncAssn

  17. Tri-County Electric Coop, Inc (Oklahoma) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems IncAssnOklahoma) Jump

  18. Tri-County Electric Coop, Inc (Texas) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems IncAssnOklahoma)

  19. Tri-County Electric Coop, Inc | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop IncIowa (Utility Company) Jump to: navigation,Power Systems

  20. Microsoft Word - Tri-State Case Study.docx

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergyTher i nAand DOE SafetyofDepartment. " 21 ranDay:OCIO AuditU .Memorandum

  1. Tri-County Elec Member Corp (Kentucky) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EISTJThin Film SolarTown ofTransportToolkitTrenton,Kentucky) Jump to:

  2. Tri-County Elec Member Corp (Tennessee) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EISTJThin Film SolarTown ofTransportToolkitTrenton,Kentucky) Jump

  3. Have You Ever Tried Composting? | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢ £ ¤ ¤ ¥ ¦ § ¨

  4. Microsoft Word - Application for Leave Tri-Form.docx

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformationJessework uses concrete and realisticQuarter

  5. A Heart of Gold? Try Platinum | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative FuelsofProgram:Y-12 Beta-3 Racetracks25 AMO PeerServices6Program Management »AAAA

  6. Office of Small and Disadvantaged Business Utilization Tri-Fold |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuelsof EnergyApril 2014DepartmentCouncil Meeting notes,Security

  7. Laboratory Directed Research & Development (LDRD) Tri-Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousand CubicResource andfirstDeviceLabLaborperformance

  8. Learning Active Facial Patches for Expression Analysis , Qingshan Liu

    E-Print Network [OSTI]

    Huang, Junzhou

    expressions are invoked by a small number of facial muscles around the mouth, nose and eyes (See Figure 1(a.g. around mouth, eye), we try to discover the common and specific patches which are important to dis- pressions are located around mouth, nose, and eyes, and their locations are essential for explaining

  9. The effect of head size/shape, miscentering, and bowtie filter on peak patient tissue doses from modern brain perfusion 256-slice CT: How can we minimize the risk for deterministic effects?

    SciTech Connect (OSTI)

    Perisinakis, Kostas; Seimenis, Ioannis; Tzedakis, Antonis; Papadakis, Antonios E.; Damilakis, John

    2013-01-15

    Purpose: To determine patient-specific absorbed peak doses to skin, eye lens, brain parenchyma, and cranial red bone marrow (RBM) of adult individuals subjected to low-dose brain perfusion CT studies on a 256-slice CT scanner, and investigate the effect of patient head size/shape, head position during the examination and bowtie filter used on peak tissue doses. Methods: The peak doses to eye lens, skin, brain, and RBM were measured in 106 individual-specific adult head phantoms subjected to the standard low-dose brain perfusion CT on a 256-slice CT scanner using a novel Monte Carlo simulation software dedicated for patient CT dosimetry. Peak tissue doses were compared to corresponding thresholds for induction of cataract, erythema, cerebrovascular disease, and depression of hematopoiesis, respectively. The effects of patient head size/shape, head position during acquisition and bowtie filter used on resulting peak patient tissue doses were investigated. The effect of eye-lens position in the scanned head region was also investigated. The effect of miscentering and use of narrow bowtie filter on image quality was assessed. Results: The mean peak doses to eye lens, skin, brain, and RBM were found to be 124, 120, 95, and 163 mGy, respectively. The effect of patient head size and shape on peak tissue doses was found to be minimal since maximum differences were less than 7%. Patient head miscentering and bowtie filter selection were found to have a considerable effect on peak tissue doses. The peak eye-lens dose saving achieved by elevating head by 4 cm with respect to isocenter and using a narrow wedge filter was found to approach 50%. When the eye lies outside of the primarily irradiated head region, the dose to eye lens was found to drop to less than 20% of the corresponding dose measured when the eye lens was located in the middle of the x-ray beam. Positioning head phantom off-isocenter by 4 cm and employing a narrow wedge filter results in a moderate reduction of signal-to-noise ratio mainly to the peripheral region of the phantom. Conclusions: Despite typical peak doses to skin, eye lens, brain, and RBM from the standard low-dose brain perfusion 256-slice CT protocol are well below the corresponding thresholds for the induction of erythema, cataract, cerebrovascular disease, and depression of hematopoiesis, respectively, every effort should be made toward optimization of the procedure and minimization of dose received by these tissues. The current study provides evidence that the use of the narrower bowtie filter available may considerably reduce peak absorbed dose to all above radiosensitive tissues with minimal deterioration in image quality. Considerable reduction in peak eye-lens dose may also be achieved by positioning patient head center a few centimeters above isocenter during the exposure.

  10. Results of the searches for pentaquarks with strangeness in DIS at HERA

    E-Print Network [OSTI]

    S. Chekanov

    2005-10-20

    The K0s-p invariant mass spectrum was reconstructed in several kinematic regions with the main emphasis on the studies of the production mechanism of the Theta+ candidate recently observed by ZEUS. The candidate Theta+ signal was found to be produced predominantly in the forward hemisphere in the laboratory frame. This is unlike the case for the Lambda(1520) or the Lambda(c), and indicates that the Theta+ may have an unusual production mechanism related to proton-remnant fragmentation. H1 does not observe a signal and sets an upper limit at 95% C.L. which does not exclude the ZEUS observation.

  11. Student Name: Jackie Nguyen Section: Humanities 1C, DIS C9 (29049)

    E-Print Network [OSTI]

    Burke, Kieron

    characters. By using specific cinematic techniques, Mulvey argues, filmmakers have typically made the female of which are utilized in Aronofsky's film. The cinematic representation of female characters in Black Swan

  12. In our study, we estimated depth dis-tributions and fishery selectivities for

    E-Print Network [OSTI]

    fishes in the deep- water fishery depend on length and age because of ontogenetic migration (move- ment distributions and ontogenetic migration are impor- tant because they affect many aspects of the deep-water fishery, including se- lectivity of commercial bottom trawls, which are the primary fishing gear. Fishery

  13. $?_{DIS}(?N)$, NLO Perturbative QCD and O(1 GeV) Mass Corrections

    E-Print Network [OSTI]

    S. Kretzer; M. H. Reno

    2004-10-13

    The deep-inelastic neutrino-nucleon cross section is one of the components of few GeV neutrino interactions. We present here our results for neutrino-isoscalar nucleon charged current scattering including perturbative next-to-leading order QCD corrections, target mass corrections, charm mass and lepton mass corrections.

  14. Quantifying (dis)agreement between direct detection experiments in a halo-independent way

    SciTech Connect (OSTI)

    Feldstein, Brian; Kahlhoefer, Felix, E-mail: brian.feldstein@physics.ox.ac.uk, E-mail: felix.kahlhoefer@physics.ox.ac.uk [Rudolf Peierls Centre for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom)

    2014-12-01

    We propose an improved method to study recent and near-future dark matter direct detection experiments with small numbers of observed events. Our method determines in a quantitative and halo-independent way whether the experiments point towards a consistent dark matter signal and identifies the best-fit dark matter parameters. To achieve true halo independence, we apply a recently developed method based on finding the velocity distribution that best describes a given set of data. For a quantitative global analysis we construct a likelihood function suitable for small numbers of events, which allows us to determine the best-fit particle physics properties of dark matter considering all experiments simultaneously. Based on this likelihood function we propose a new test statistic that quantifies how well the proposed model fits the data and how large the tension between different direct detection experiments is. We perform Monte Carlo simulations in order to determine the probability distribution function of this test statistic and to calculate the p-value for both the dark matter hypothesis and the background-only hypothesis.

  15. Pamuk’s Dis-orient: Reassembling Kafka’s Castle in Snow (2002)

    E-Print Network [OSTI]

    Gramling, David J

    2007-01-01

    YayPnlarP, 2002. Pamuk, Orhan. Snow. Trans. Maureen Freely.of the land” come into Pamuk, Snow 15. “‘Bizden ayrPldPktanbe reading his new poem “Snow” before a public audience. Ka

  16. Dis/locating audience : transnational media flows and the online circulation of East Asian television drama

    E-Print Network [OSTI]

    Li, Xiaochang, S.M. Massachusetts Institute of Technology

    2009-01-01

    It is commonly accepted that media and communication technologies play pivotal roles in the complex processes of what is broadly termed "globalization." The increasing speed, volume, and scale of transnational circulation ...

  17. Achieving Energy Performance in spite of complex systems and dis-jointed design 

    E-Print Network [OSTI]

    Ardren, C.; Bannister, P.

    2012-01-01

    to a bare shell, before being re-created to a Grade A office with numerous tenant systems, including a 125kW data centre with a series of complex multi-layered alarm and protection systems. Given the extent of incomplete or contradictory designs...

  18. Inclusive Two-Gluon and Valence Quark-Gluon Production in DIS and pA

    E-Print Network [OSTI]

    Jamal Jalilian-Marian; Yuri V. Kovchegov

    2005-03-17

    We calculate production cross sections of a forward quark-gluon pair and of two gluons at mid-rapidity in Deep Inelastic Scattering and in high energy proton-nucleus collisions. The calculation is performed in the framework of the Color Glass Condensate formalism. We first calculate the cross sections in the quasi-classical approximation, which includes multiple rescatterings in the target. We then proceed to include the effects of non-linear small-x evolution in the production cross sections. It is interesting to note that our result for the two-gluon production cross section appears to be in direct violation of AGK cutting rules, which is the first example of such violation in QCD. The calculated quark-gluon and gluon-gluon production cross sections can be used to construct theoretical predictions for two-particle azimuthal correlations at RHIC and LHC (I^{p(d)A}) as well as for Deep Inelastic Scattering experiments at HERA and eRHIC.

  19. Higher twists in polarized DIS and the size of the constituent quark

    SciTech Connect (OSTI)

    Alexander Sidorov; Christian Weiss

    2006-02-15

    The spontaneous breaking of chiral symmetry implies the presence of a short-distance scale in the QCD vacuum, which phenomenologically may be associated with the ''size'' of the constituent quark, rho {approx} 0.3 fm. We discuss the role of this scale in the matrix elements of the twist-4 and 3 quark-gluon operators determining the leading power (1/Q{sup 2}-) corrections to the moments of the nucleon spin structure functions. We argue that the flavor-nonsinglet twist-4 matrix element, f{sub 2}{sup u-d}, has a sizable negative value of the order rho{sup -2}, due to the presence of sea quarks with virtualities {approx} rho{sup -2} in the proton wave function. The twist-3 matrix element, d{sub 2}, is not related to the scale rho{sup -2}. Our arguments support the results of previous calculations of the matrix elements in the instanton vacuum model. We show that this qualitative picture is in agreement with the phenomenological higher-twist correction extracted from an NLO QCD fit to the world data on g{sub 1}{sup p} and g{sub 1}{sup n}, which include recent data from the Jefferson Lab Hall A and COMPASS experiments. We comment on the implications of the short-distance scale rho for quark-hadron duality and the x-dependence of higher-twist contributions.

  20. The DIS(chi) Scheme for Heavy Quark Production at Small x.

    E-Print Network [OSTI]

    White, C D

    (nf ) g(nf ) ) , (1) 1 February 2, 2008 6:9 Proceedings Trim Size: 9in x 6in Cavendish-HEP-2006/12 2 which defines the heavy matrix elements {Aij}. This leads to an ambiguity in the VF coefficient functions. For example, at O(?S), one finds: CV F (0)2,H ?A... . The resummed prediction is compared with data alongside a standard NLO prediction from a global fit in figure 1. The resummed 0.5 1 1.5 2 2.5 3 1 10 H1 (×1.02) ZEUS (×1.004) x=5×10-5 x=6.3×10-5 x=8×10-5 x=1.3×10-4 x=1.61×10-4 x=2×10-4 x=2.53×10-4 x=3.2×10-4 x=4...

  1. Wanderl[o]st: Lost Identities and Losing Place in the New World (Dis)Order

    E-Print Network [OSTI]

    Whitney, Kendall Abbott

    2009-04-22

    Through the investigation of works by contemporary Spanish and Spanish-American writers--Roberto Bolaño, Abilio Estévez, Lucía Etxebarria, Ray Loriga, and Antonio José Ponte--this project explores subjects that get lost ...

  2. Page36 March 2015 taste. Maple products also have a dis-

    E-Print Network [OSTI]

    Hayden, Nancy J.

    that are pure, highly sustainable and possess a small carbon footprint compared to coconut water. Maple sap-permeate beverage, one birch sap beverage, and one coconut water used for comparative purposes (only the maple

  3. Unsettling the archive : dis- imagining colonial subjects to re-imagine knowledge production

    E-Print Network [OSTI]

    Beebe, Laura L.

    2012-01-01

    Coulthard,  Glen  S.  "Subjects  of  Empire:  Indigenous  imagining  Colonial  Subjects  to  Re-­?imagine  Knowledge  become  pure  speculation  subject  only  to  the  demands  

  4. Research Articles J Vect Borne Dis 43, June 2006, pp. 4352

    E-Print Network [OSTI]

    Sharma, Shobhona

    of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai, India Abstract Background & objectives: Glycolysis is the sole source of energy for the intraerythrocytic stages of Plasmodium falciparum, making glycolytic resistance2. Renewed efforts are required to develop novel and affordable antimalarials to overcome

  5. Pamuk’s Dis-orient: Reassembling Kafka’s Castle in Snow (2002)

    E-Print Network [OSTI]

    Gramling, David J

    2007-01-01

    indirect routes binding Germany to Turkey. Pamuk’s multi-in Germany, and as a “German journalist” when in Turkey, Ka

  6. Comparison of NNLO DIS scheme splitting functions with results from exact gluon kinematics at small x.

    E-Print Network [OSTI]

    White, C D; Thorne, Robert S

    ) = ?S ? ? 0 dk2 k2 hi(k2/Q2)f(N, k2, Q20)gB(N,Q 2 0), (1) where gB is the bare gluon distribution at momentum scale Q20, and the strong coupling ?S is fixed at LL order. The hi(k2/Q2) are the impact factors coupling the virtual photon to the gluon... )gB(N,Q 2 0), (2) which serves to define the impact factor h2. In a general factorisation scheme, one loses the simple inter- pretation of h2 as the coefficient function relating the gluon distribution to the structure function. Instead it represents...

  7. Peripheral (Dis)Unity: The Italian Influences on Corsican Linguistic and Cultural Developments

    E-Print Network [OSTI]

    Oliva, Cedric J.

    2012-01-01

    differentiation made in romance genealogy, that the Corsicans separate lan- guage genealogy and structure from French,studies on language genealogy and sociolinguistic work on

  8. /Users/jzennamo/Desktop/ObsLimit_MiniSciBooNE_SBN_numuDis.pdf

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAboutXuRod Hunt (208)InventorHow to Save(ANL-IN-03-032). µ θ 2 2

  9. Careers and disAbled DC Career Expo | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirley Ann JacksonDepartment|Marketing, LLCEfficiencyCOP 21: The06(201) |13, 2015 10:00AM to 3:00PM

  10. DOE - Office of Legacy Management -- Seymour CT Site - CT 02

    Office of Legacy Management (LM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth DakotaRobbins and Myers Co - OH 51Savannah River Swamp

  11. SU-D-18A-06: Variation of Controlled Breath Hold From CT Simulation to Treatment and Its Dosimetric Impact for Left-Sided Breast Radiotherapy with a Real-Time Optical Tracking System

    SciTech Connect (OSTI)

    Mittauer, K; Deraniyagala, R; Li, J; Lu, B; Liu, C; Lightsey, J; Yan, G

    2014-06-01

    Purpose: Different breath-hold (BH) maneuvers (abdominal breathing vs. chest breathing) during CT simulation and treatment can lead to chest wall positional variation. The purpose of this study is to quantify the variation of active breathing control (ABC)-assisted BH and estimate its dosimetric impact for left-sided whole-breast radiotherapy with a real-time optical tracking system (OTS). Methods: Seven breast cancer patients were included. An in-house OTS tracked an infrared (IR) marker affixed over the xiphoid process of the patient at CT simulation and throughout the treatment course to measure BH variations. Correlation between the IR marker and the breast was studied for dosimetric purposes. The positional variations of 860 BHs were retrospectively incorporated into treatment plans to assess their dosimetric impact on breast and cardiac organs (heart and left anterior descending artery [LAD]). Results: The mean intrafraction variations were 2.8 mm, 2.7 mm, and 1.6 mm in the anteroposterior (AP), craniocaudal (CC), and mediolateral (ML) directions, respectively. Mean stability in any direction was within 1.5 mm. A general trend of BH undershoot at treatment relative to CT simulation was observed with an average of 4.4 mm, 3.6 mm, and 0.1 mm in the AP, CC, and ML directions, respectively. Undershoot up to 12.6 mm was observed for individual patients. The difference between the planned and delivered dose to breast targets was negligible. The average planned/delivered mean heart doses, mean LAD doses, and max LAD doses were 1.4/2.1, 7.4/15.7, and 18.6/31.0 Gy, respectively. Conclusion: Systematic undershoot was observed in ABC-assisted BHs from CT simulation to treatment. Its dosimetric impact on breast coverage was minimized with image guidance, but the benefits of cardiac organ sparing were degraded. A real-time tracking system can be used in junction with the ABC device to improve BH reproducibility.

  12. Dose equations for shift-variant CT acquisition modes using variable pitch, tube current, and aperture, and the meaning of their associated CTDI{sub vol}

    SciTech Connect (OSTI)

    Dixon, Robert L.; Boone, John M.; Kraft, Robert A.

    2014-11-01

    Purpose: With the increasing clinical use of shift-variant CT protocols involving tube current modulation (TCM), variable pitch or pitch modulation (PM), and variable aperture a(t), the interpretation of the scanner-reported CTDI{sub vol} is called into question. This was addressed for TCM in their previous paper published by Dixon and Boone [Med. Phys. 40, 111920 (14pp.) (2013)] and is extended to PM and concurrent TCM/PM as well as variable aperture in this work. Methods: Rigorous convolution equations are derived to describe the accumulated dose distributions for TCM, PM, and concurrent TCM/PM. A comparison with scanner-reported CTDI{sub vol} formulae clearly identifies the source of their differences with the traditional CTDI{sub vol}. Dose distribution simulations using the convolution are provided for a variety of TCM and PM scenarios including a helical shuttle used for perfusion studies (as well as constant mA)—all having the same scanner-reported CTDI{sub vol}. These new convolution simulations for TCM are validated by comparison with their previous discrete summations. Results: These equations show that PM is equivalent to TCM if the pitch variation p(z) is proportional to 1/i(z), where i(z) is the local tube current. The simulations show that the local dose at z depends only weakly on the local tube current i(z) or local pitch p(z) due to scatter from all other locations along z, and that the “local CTDI{sub vol}(z)” or “CTDI{sub vol} per slice” do not represent a local dose but rather only a relative i(z) or p(z). The CTDI-paradigm does not apply to shift-variant techniques and the scanner-reported CTDI{sub vol} for the same lacks physical significance and relevance. Conclusions: While the traditional CTDI{sub vol} at constant tube current and pitch conveys useful information (the peak dose at the center of the scan length), CTDI{sub vol} for shift-variant techniques (TCM or PM) conveys no useful information about the associated dose distribution it purportedly represents. On the other hand, the total energy absorbed E (“integral dose”) as well as its surrogate DLP remain robust (invariant) with respect to shift-variance, depending only on the total mAs = ?i?t{sub 0} accumulated during the total beam-on time t{sub 0} and aperture a, where ?i? is the average current.

  13. SU-E-J-167: Improvement of Time-Ordered Four Dimensional Cone-Beam CT; Image Mosaicing with Real and Virtual Projections

    SciTech Connect (OSTI)

    Nakano, M; Kida, S; Masutani, Y; Shiraki, T; Yamamoto, K; Shiraishi, K; Nakagawa, K; Haga, A [University of Tokyo Hospital, Bunkyo-ku, Tokyo (Japan)

    2014-06-01

    Purpose: In the previous study, we developed time-ordered fourdimensional (4D) cone-beam CT (CBCT) technique to visualize nonperiodic organ motion, such as peristaltic motion of gastrointestinal organs and adjacent area, using half-scan reconstruction method. One important obstacle was that truncation of projection was caused by asymmetric location of flat-panel detector (FPD) in order to cover whole abdomen or pelvis in one rotation. In this study, we propose image mosaicing to extend projection data to make possible to reconstruct full field-of-view (FOV) image using half-scan reconstruction. Methods: The projections of prostate cancer patients were acquired using the X-ray Volume Imaging system (XVI, version 4.5) on Synergy linear accelerator system (Elekta, UK). The XVI system has three options of FOV, S, M and L, and M FOV was chosen for pelvic CBCT acquisition, with a FPD panel 11.5 cm offset. The method to produce extended projections consists of three main steps: First, normal three-dimensional (3D) reconstruction which contains whole pelvis was implemented using real projections. Second, virtual projections were produced by reprojection process of the reconstructed 3D image. Third, real and virtual projections in each angle were combined into one extended mosaic projection. Then, 4D CBCT images were reconstructed using our inhouse reconstruction software based on Feldkamp, Davis and Kress algorithm. The angular range of each reconstruction phase in the 4D reconstruction was 180 degrees, and the range moved as time progressed. Results: Projection data were successfully extended without discontinuous boundary between real and virtual projections. Using mosaic projections, 4D CBCT image sets were reconstructed without artifacts caused by the truncation, and thus, whole pelvis was clearly visible. Conclusion: The present method provides extended projections which contain whole pelvis. The presented reconstruction method also enables time-ordered 4D CBCT reconstruction of organs with non-periodic motion with full FOV without projection-truncation artifacts. This work was partly supported by the JSPS Core-to-Core Program(No. 23003). This work was partly supported by JSPS KAKENHI 24234567.

  14. Brassersplein 2 2612 CT Delft

    E-Print Network [OSTI]

    Langendoen, Koen

    interfaces. A smart-phone, for example, may possess 3G, 4G, Wi-Fi, Bluetooth and NFC interfaces. Situations and network layer modules. Development of a MATLAB tool that can evaluate communication link performance depending on In general, the objective of this MSc project is modeling, simulation and possibly hardware

  15. Medical Imaging Computed Tomography (CT)

    E-Print Network [OSTI]

    Massey, Thomas N.

    #12;LSO-APD Array Schematic #12;Time-of-Flight PET #12;Energy Spectrum with lutetium oxyorthosilicate

  16. CT Offshore | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LIST OFAMERICA'SHeavy Electricals Ltd BHEL JumpCMNA Power Jump to:Offshore Jump to:

  17. Enhancement of lanthanide evaporation by complexation: Dysprosium tri-iodide mixed with indium iodide and thulium tri-iodide mixed with thallium iodide

    SciTech Connect (OSTI)

    Curry, J. J.; Henins, A.; Hardis, J. E.; Estupiñán, E. G.; Lapatovich, W. P.; Shastri, S. D.

    2013-09-28

    The vapors in equilibrium with condensates of DyI{sub 3}, DyI{sub 3}/InI, TmI{sub 3}, and TmI{sub 3}/TlI were observed over the temperature range from 900 K to 1400 K using x-ray induced fluorescence. The total densities of each element (Dy, Tm, In, Tl, and I) in the vapor, summed over all atomic and molecular species, were determined. Dramatic enhancements in the total vapor densities of Dy and Tm were observed in the vapors over DyI{sub 3}/InI and TmI{sub 3}/TlI as compared to the vapors over pure DyI{sub 3} and pure TmI{sub 3}, respectively. An enhancement factor exceeding 10 was observed for Dy at T? 1020 K, decreasing to 0 at T? 1250 K. An enhancement factor exceeding 20 was observed for Tm at T? 1040 K, decreasing to 0 at T? 1300 K. Such enhancements are expected from the formation of the vapor-phase hetero-complexes DyInI{sub 4} and TmTlI{sub 4}. Numerical simulations of the thermo-chemical equilibrium suggest the importance of additional complexes in liquid phases. A description of the measurement technique is given. Improvements in the absolute calibration lead to an approximately 40% correction to previously reported preliminary results [J. J. Curry et al., Chem. Phys. Lett. 507, 52 (2011); Appl. Phys. Lett. 100, 083505 (2012)].

  18. PROJECT DESCRIPTION In recent years there has been a rapid proliferation of large interconnected and spatially dis-

    E-Print Network [OSTI]

    Schenato, Luca

    , communication and computation capabilities are added to these networks, resulting in smart-grids with a large

  19. Rev. Int. Met. Num. Calc. Dis. Ing. (2010) 26: 83-107 Una formulacion numerica de volumenes finitos de alto

    E-Print Network [OSTI]

    Colominas, Ignasi

    2010-01-01

    ´umenes finitos de alto orden basada en el m´etodo de M´inimos Cuadrados M´oviles para flujo compresible X´erica para el c´alculo de flujos compresibles tanto en mallas estructuradas como en mallas no es- tructuradas the accuracy and robust- ness of the numerical method. 1. INTRODUCCI´ON El m´etodo de vol´umenes finitos tipo

  20. Statement on Copyright The statement that follows was approved in March 1999 by the Association's Special Committee on Dis-

    E-Print Network [OSTI]

    Van Volkenburgh, Elizabeth

    by the Association's Council and endorsed by the Eighty-fifth Annual Meeting in June 1999. T he objective214 Statement on Copyright The statement that follows was approved in March 1999 by the Association the control and direction of the employer; the employee is accountable to the employer for the content