National Library of Energy BETA

Sample records for argus halon suppression

  1. Memorandum, Managed Phase Out of Halon Fixed Fire Suppression Systems- May 5, 1993

    Broader source: Energy.gov [DOE]

    The purpose of this memorandum is to provide additional interim departmental criteria on the management of the reduction and potential elimination of Halon fire extinguishing systems within the Department of Energy (DOE). This memorandum supplements the joint Office of Safety and Quality Assurance/Office of Projects and Facilities Management memorandum of September 27, 1990, in which guidance was provided on the installation of new Halon 1301 fixed fire suppression systems and halon 1211 portable fire extinguishers.

  2. Argus Power Technology | Open Energy Information

    Open Energy Info (EERE)

    Argus Power Technology Jump to: navigation, search Name: Argus Power Technology Place: Zhengzhou, Henan Province, China Zip: 450001 Product: China-based company that manufactures...

  3. Health effects of Halon 1301 exposure

    SciTech Connect (OSTI)

    Holness, D.L.; House, R.A. )

    1992-07-01

    An accidental discharge of a Halon 1301 system is reported. Thirty-one workers were assessed, 22 who were present at the time of the discharge, and 9 who worked the next shift. The incident was complicated by a small Freon-22 leak several hours later. Throat, eye, and nasal irritation and lightheadedness were reported by the majority of workers. Workers present during the halon discharge reported significantly more lightheadedness, headache, voice change, cough, and a fast heartbeat than did those who worked the later shift. These differences were significant even after correcting for confounding factors such as age, sex, and sense of anxiety at the time of the incident. The possible causes for the irritant symptoms include breakdown products of Halon 1301 and Freon-22 or contaminants from the halon discharge system. Although these irritant effects may not be an effect of Halon 1301 alone, they may occur in these discharge situations, and workers should be advised of this possibility. The possible cardiac and central nervous system effects also should be considered. The importance of a clear-cut protocol to deal with such incidents as well as worker education are discussed.

  4. ARGUS-PRIMA: Wind Power Prediction | Argonne National Laboratory

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

    ARGUS-PRIMA: Wind Power Prediction ARGUS-PRIMA: Wind Power Prediction ARGUS-PRIMA is a software platform for testing statistical algorithms for short-term wind power forecasting. ...

  5. Requirements And Instructions For Shipping Halon To The Defense Logistics Agency (DLA) Halon Repository

    Broader source: Energy.gov [DOE]

    Disposition of excess Halon 1301 is now done in accordance with Executive Order 13148 — “Greening the Government Through Leadership in Environmental Management ”, Section 505 (c). An SF-122 form (or equivalent documentation) should be approved by the DLA prior to shipment.

  6. Dissemination and support of ARGUS for accelerator applications

    SciTech Connect (OSTI)

    Not Available

    1993-02-01

    The ARGUS code is a three-dimensional code system for simulating the interactions between charged particles, electric and magnetic fields, and complex structures. It is a system of modules that share common utilities for grid and structure input, data handling, memory management, diagnostics, and other specialized functions. The code includes the fields due to the space charge and current density of the particles to achieve a self-consistent treatment of the particle dynamics.The physics modules in ARGUS include three-dimensional field solvers for electrostatics and electromagnetics, a three-dimensional electromagnetic frequency-domain module, a full particle-in-cell (PIC) simulation module, and a steady-state PIC model. This project has a primary mission of developing the capabilities of ARGUS in accelerator modeling for release to the accelerator design community. This year has seen the development of a new frequency domain module for ARGUS, a new chemistry module, and a first version of an interactive user interface. In addition, improvements to treat lossy materials in the frequency domain and to use cylindrical coordinates with all modules are in progress, and will be released in an ARGUS upgrade planned for release in July, 1993. SAIC has also developed a workstation version of ARGUS that will be made available to beta- testers, starting with the release of ARGUS v.25. The LAACG has become a full partner with SAIC, and is now poised to work with SAIC to support the upcoming release of ARGUS version 25. This coming year will include one or more release workshops to introduce ARGUS v.25 to prospective users.

  7. CX-014318: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    735-A, D-Wing, Main Floor - ARGUS and ANSUL Halon Suppression Systems Replacement CX(s) Applied: B2.5Date: 08/13/2015 Location(s): South CarolinaOffices(s): Savannah River Operations Office

  8. ARG-US Remote Area Modular Monitoring (RAMM) | Argonne National Laboratory

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

    ARG-US Remote Area Modular Monitoring (RAMM) ARG-US Remote Area Modular Monitoring (RAMM) Scientists at Argonne National Laboratory have developed a technology to make nuclear and radiological facilities safer by better monitoring both plant conditions as well as the most sensitive materials onsite. The patent-pending system, called ARG-US Remote Area Modular Monitoring, or RAMM, uses hig- tech sensors paired with redundant, self-healing communications platforms that can work even in the most

  9. Argus Energy WV, LLC wins 2007 Wetlands West Virginia Award

    SciTech Connect (OSTI)

    2007-07-15

    Argus Energy's Kiah Creek Operation has received the 2007 Wetlands West Virginia Award presented by the West Virginian Coal Association. The operation was originally a 1267 acre underground mine in the Coalburg seam. Underground mining commenced in 2000 until the end of 2003 with more than two million tons of coal being produced. The creation of the wetlands was achieved during the operations. 8 photos.

  10. A nondestructive test for aircraft Halon bottles, the development of an acoustic emission application

    SciTech Connect (OSTI)

    Beattie, A.G.

    1996-12-01

    An acoustic emission test for aircraft Halon bottles has been developed in response to a need expressed by the US Airline Industry. During this development many choices had to be made about test methods, procedures and analysis techniques. This paper discusses these choices and how successful they were. The test itself was designed to replace the currently required hydrostatic test for these bottles. The necessary load is applied by heating the sealed bottles. Acoustic emission is monitored, during the heating, by six sensors held in position by a special fixture. A prototype of the test apparatus was constructed and used in two commercial Halon bottle repair and test facilities. Results to date indicate that about 97% of the bottles tested show no indications of flaws. The other 3% have had indications of possible flaws in non-critical areas of the bottles. All bottles tested to date have passed the hydrostatic test subsequent to the acoustic emission test.

  11. Dissemination and support of ARGUS for accelerator applications. Technical progress report, January 21, 1992--February 1, 1993

    SciTech Connect (OSTI)

    Not Available

    1993-02-01

    The ARGUS code is a three-dimensional code system for simulating the interactions between charged particles, electric and magnetic fields, and complex structures. It is a system of modules that share common utilities for grid and structure input, data handling, memory management, diagnostics, and other specialized functions. The code includes the fields due to the space charge and current density of the particles to achieve a self-consistent treatment of the particle dynamics.The physics modules in ARGUS include three-dimensional field solvers for electrostatics and electromagnetics, a three-dimensional electromagnetic frequency-domain module, a full particle-in-cell (PIC) simulation module, and a steady-state PIC model. This project has a primary mission of developing the capabilities of ARGUS in accelerator modeling for release to the accelerator design community. This year has seen the development of a new frequency domain module for ARGUS, a new chemistry module, and a first version of an interactive user interface. In addition, improvements to treat lossy materials in the frequency domain and to use cylindrical coordinates with all modules are in progress, and will be released in an ARGUS upgrade planned for release in July, 1993. SAIC has also developed a workstation version of ARGUS that will be made available to beta- testers, starting with the release of ARGUS v.25. The LAACG has become a full partner with SAIC, and is now poised to work with SAIC to support the upcoming release of ARGUS version 25. This coming year will include one or more release workshops to introduce ARGUS v.25 to prospective users.

  12. ARG-US RADIO FREQUENCY IDENTIFICATION (RFID) Technology (IN-08-046) -

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

    Energy Innovation Portal ARG-US RADIO FREQUENCY IDENTIFICATION (RFID) Technology (IN-08-046) Tracking and Monitoring Technology that will Modernize the Management of Nuclear and Radioactive Materials, and other sensitive items Argonne National Laboratory Contact ANL About This Technology <em>Drum with RFID tag attached</em> Drum with RFID tag attached Technology Marketing Summary For years, radio frequency identification (RFID) technology has been used in a variety of

  13. Proposed methodology for combustion toxicology testing of combined halon replacement agent/jet fuel interaction. Final report, June-September 1991

    SciTech Connect (OSTI)

    Kibert, C.J.

    1993-04-01

    An international consensus to remove Chlorofluorocarbon (CFC) compounds from production and U.S. national policy to implement the resulting protocols has motivated the U.S. Air Force to embark on a program to find a suitable replacement for Halon 1211, currently used to extinguish flight line fires. This research addressed the feasibility of conducting a combustion toxicology (CT) program to assess the toxic products of the combustion interaction of JP-8 and the Group 1 or so-called Near Term candidate replacement agents for Halon 1211: HCFCs -123, -124, and -142b. A laboratory scale experiment benchmarked on large scale testing of a 150 sq ft pool fire was developed on the basis of Froude scaling of the full scale fire to a 15 x 15 cm pan fire. A prototype apparatus was developed and investigation into the use of animal behavior methods as an indicator of human incapacitation was conducted. The result is a new method which may potentially be utilized for future toxicity studies of the combustion interaction of current and future U.S. Air Force fuels with various fire extinguishants. Extinguishing agents, Halon 1211, Halon replacement, Combustion.

  14. Food consumption and digestion time estimation of spotted scat, Scatophagus argus, using X-radiography technique

    SciTech Connect (OSTI)

    Hashim, Marina; Abidin, Diana Atiqah Zainal; Das, Simon K.; Ghaffar, Mazlan Abd.

    2014-09-03

    The present study was conducted to investigate the food consumption pattern and gastric emptying time using x-radiography technique in scats fish, Scatophagus argus feeding to satiation in laboratory conditions. Prior to feeding experiment, fish of various sizes were examined their stomach volume, using freshly prepared stomachs ligatured at the tips of the burret, where the maximum amount of distilled water collected in the stomach were measured (ml). Stomach volume is correlated with maximum food intake (S{sub max}) and it can estimate the maximum stomach distension by allometric model i.e volume=0.0000089W{sup 2.93}. Gastric emptying time was estimated using a qualitative X-radiography technique, where the fish of various sizes were fed to satiation at different time since feeding. All the experimental fish was feed into satiation using radio-opaque barium sulphate (BaSO{sub 4}) paste injected in the wet shrimp in proportion to the body weight. The BaSO{sub 4} was found suitable to track the movement of feed/prey in the stomach over time and gastric emptying time of scats fish can be estimated. The results of qualitative X-Radiography observation of gastric motility, showed the fish (200 gm) that fed to maximum satiation meal (circa 11 gm) completely emptied their stomach within 30 - 36 hrs. The results of the present study will provide the first baseline information on the stomach volume, gastric emptying of scats fish in captivity.

  15. SIMPJ21541055: A NEW LOW-GRAVITY L4? BROWN DWARF CANDIDATE MEMBER OF THE ARGUS ASSOCIATION

    SciTech Connect (OSTI)

    Gagn, Jonathan; Lafrenire, David; Doyon, Ren; Artigau, tienne; Malo, Lison; Robert, Jasmin; Nadeau, Daniel

    2014-09-01

    We present SIMPJ215434541055308, a new L4? brown dwarf identified in the SIMP survey that displays signs of low gravity in its near-infrared spectrum. Using BANYAN II, we show that it is a candidate member of the Argus association, albeit with a 21% probability that it is a contaminant from the field. Measurements of radial velocity and parallax will be needed to verify its membership. If it is a member of Argus (age 30-50Myr), then this object would have a planetary mass of 10 0.5M {sub Jup}.

  16. Disordered crystal structure of 20H-AlON, Al{sub 10}O{sub 3}N{sub 8}

    SciTech Connect (OSTI)

    Banno, Hiroki; Funahashi, Shiro; Asaka, Toru; Hirosaki, Naoto; Fukuda, Koichiro

    2015-10-15

    The disordered crystal structure of 20H-AlON (Al{sub 10}O{sub 3}N{sub 8}) was determined by combined use of X-ray powder diffraction and transmission electron microscopy. The title compound is hexagonal with space group P6{sub 3}/mmc (Z=2) and the unit-cell dimensions are a=0.307082(5) nm, c=5.29447(8) nm and V=0.432376(12) nm{sup 3}. The structural model showed the positional disordering of three of the six Al sites in the unit cell. The reliability indices calculated from the Rietveld method were R{sub wp}=6.97%, S (=R{sub wp}/R{sub e})=1.68, R{sub p}=5.45%, R{sub B}=5.13% and R{sub F}=4.56%. We interpreted the disordered structure of 20H-AlON as a statistical average of six different types of ordered structural configurations, which are composed of an octahedral [Al(O, N){sub 6}] layer and tetrahedral [Al(O, N){sub 4}] layers. We demonstrated the high correlations between the hexagonal unit-cell dimensions and the octahedral layer concentrations for AlON and SiAlON polytypoids. - Graphical abstract: Variations of a and c/(n{sub O}+n{sub T}) with n{sub O}/(n{sub O}+n{sub T}). The a and c are the hexagonal unit-cell dimensions of AlON, SiAlON and AlN. The n{sub O} and n{sub T} are, respectively, the numbers of octahedral and tetrahedral layers in the unit cells. The unit-cell dimensions in literature are plotted in black plus for AlON and black cross for SiAlON. The unit-cell dimensions of AlN are a=0.3110 nm and c=0.4980 nm. - Highlights: • Crystal structure of Al10O3N8 is determined by laboratory X-ray powder diffraction. • The atom arrangements are represented by the split-atom model. • Six types of ordered atom arrangements are derived from the disordered structure. • Hexagonal unit-cell dimensions changed systematically for AlON and SiAlON compounds.

  17. Report on a 2009 mini-demonstration of the ARG-US Radio Frequency Identification (RFID) system in transportation.

    SciTech Connect (OSTI)

    Tsai, H.; Chen, K.; Jusko, M.; Craig, B.; Liu, Y.; Decision and Information Sciences

    2009-11-23

    The Packaging Certification Program (PCP) of the U.S. Department of Energy (DOE) Environmental Management (EM), Office of Packaging and Transportation (EM-14), has developed a radio frequency identification (RFID) tracking and monitoring system for the management of nuclear materials during storage and transportation. The system, developed by the PCP team at Argonne National Laboratory, consists of hardware (Mk-series sensor tags, fixed and handheld readers, form factor for multiple drum types, seal integrity sensors, and enhanced battery management), software (application programming interface, ARG-US software for local and remote/web applications, secure server and database management), and cellular/satellite communication interfaces for vehicle tracking and item monitoring during transport. The ability of the above system to provide accurate, real-time tracking and monitoring of the status of multiple, certified containers of nuclear materials has been successfully demonstrated in a week-long, 1,700-mile DEMO performed in April 2008. While the feedback from the approximately fifty (50) stakeholders who participated in and/or observed the DEMO progression were very positive and encouraging, two major areas of further improvements - system integration and web application enhancement - were identified in the post-DEMO evaluation. The principal purpose of the MiniDemo described in this report was to verify these two specific improvements. The MiniDemo was conducted on August 28, 2009. In terms of system integration, a hybrid communication interface - combining the RFID item-monitoring features and a commercial vehicle tracking system by Qualcomm - was developed and implemented. In the MiniDemo, the new integrated system worked well in reporting tag status and vehicle location accurately and promptly. There was no incompatibility of components. The robust commercial communication gear, as expected, helped improve system reliability. The MiniDemo confirmed that system

  18. ARG-US

    Energy Science and Technology Software Center (OSTI)

    2007-08-14

    The system is developed to collect, process, store and present the information provided by the radio frequency identification (RFID) devices. The system contains three parts, the application software, the database and the web page. The application software manages multiple RFID devices, such as readers and portals, simultaneously. It communicates with the devices through application programming interface (API) provided by the device vendor. The application software converts data collected by the RFID readers and portals tomore » readable information. It is capable of encrypting data using 256 bits advanced encryption standard (AES). The application software has a graphical user interface (GUI). The GUI mimics the configurations of the nucler material storage sites or transport vehicles. The GUI gives the user and system administrator an intuitive way to read the information and/or configure the devices. The application software is capable of sending the information to a remote, dedicated and secured web and database server. Two captured screen samples, one for storage and transport, are attached. The database is constructed to handle a large number of RFID tag readers and portals. A SQL server is employed for this purpose. An XML script is used to update the database once the information is sent from the application software. The design of the web page imitates the design of the application software. The web page retrieves data from the database and presents it in different panels. The user needs a user name combined with a password to access the web page. The web page is capable of sending e-mail and text messages based on preset criteria, such as when alarm thresholds are excceeded. A captured screen sample is attached. The application software is designed to be installed on a local computer. The local computer is directly connected to the RFID devices and can be controlled locally or remotely. There are multiple local computers managing different sites or transport vehicles. The control from remote sites and information transmitted to a central database server is through secured internet. The information stored in the central databaser server is shown on the web page. The users can view the web page on the internet. A dedicated and secured web and database server (https) is used to provide information security.« less

  19. ARG-US

    SciTech Connect (OSTI)

    2007-08-14

    The system is developed to collect, process, store and present the information provided by the radio frequency identification (RFID) devices. The system contains three parts, the application software, the database and the web page. The application software manages multiple RFID devices, such as readers and portals, simultaneously. It communicates with the devices through application programming interface (API) provided by the device vendor. The application software converts data collected by the RFID readers and portals to readable information. It is capable of encrypting data using 256 bits advanced encryption standard (AES). The application software has a graphical user interface (GUI). The GUI mimics the configurations of the nucler material storage sites or transport vehicles. The GUI gives the user and system administrator an intuitive way to read the information and/or configure the devices. The application software is capable of sending the information to a remote, dedicated and secured web and database server. Two captured screen samples, one for storage and transport, are attached. The database is constructed to handle a large number of RFID tag readers and portals. A SQL server is employed for this purpose. An XML script is used to update the database once the information is sent from the application software. The design of the web page imitates the design of the application software. The web page retrieves data from the database and presents it in different panels. The user needs a user name combined with a password to access the web page. The web page is capable of sending e-mail and text messages based on preset criteria, such as when alarm thresholds are excceeded. A captured screen sample is attached. The application software is designed to be installed on a local computer. The local computer is directly connected to the RFID devices and can be controlled locally or remotely. There are multiple local computers managing different sites or transport vehicles. The control from remote sites and information transmitted to a central database server is through secured internet. The information stored in the central databaser server is shown on the web page. The users can view the web page on the internet. A dedicated and secured web and database server (https) is used to provide information security.

  20. Computational fluid dynamics simulation of the air/suppressant flow in an uncluttered F18 engine nacelle

    SciTech Connect (OSTI)

    Lopez, A.R.; Gritzo, L.A.; Hassan, B.

    1997-06-01

    For the purposes of designing improved Halon-alternative fire suppression strategies for aircraft applications, Computational Fluid Dynamics (CFD) simulations of the air flow, suppressant transport, and air-suppressant mixing within an uncluttered F18 engine nacelle were performed. The release of inert gases from a Solid Propellant Gas Generator (SPGG) was analyzed at two different injection locations in order to understand the effect of injection position on the flow patterns and the mixing of air and suppression agent. An uncluttered engine nacelle was simulated to provide insight into the global flow features as well as to promote comparisons with previous nacelle fire tests and recent water tunnel tests which included little or no clutter. Oxygen concentration levels, fuel/air residence times that would exist if a small fuel leak were present, velocity contours, and streamline patterns are presented inside the engine nacelle. The numerical results show the influence of the gent release location on regions of potential flame extinction due to oxygen inerting and high flame strain. The occurrence of inflow through the exhaust ducts on the aft end of the nacelle is also predicted. As expected, the predicted oxygen concentration levels were consistently higher than the measured levels since a fire was not modeled in this analysis. Despite differences in the conditions of these simulations and the experiments, good agreement was obtained between the CFD predictions and the experimental measurements.

  1. Explosion suppression system

    DOE Patents [OSTI]

    Sapko, Michael J. (Finleyville, PA); Cortese, Robert A. (Pittsburgh, PA)

    1992-01-01

    An explosion suppression system and triggering apparatus therefor are provided for quenching gas and dust explosions. An electrically actuated suppression mechanism which dispenses an extinguishing agent into the path ahead of the propagating flame is actuated by a triggering device which is light powered. This triggering device is located upstream of the propagating flame and converts light from the flame to an electrical actuation signal. A pressure arming device electrically connects the triggering device to the suppression device only when the explosion is sensed by a further characteristic thereof beside the flame such as the pioneer pressure wave. The light powered triggering device includes a solar panel which is disposed in the path of the explosion and oriented between horizontally downward and vertical. Testing mechanisms are also preferably provided to test the operation of the solar panel and detonator as well as the pressure arming mechanism.

  2. Pressure suppression containment system

    DOE Patents [OSTI]

    Gluntz, Douglas M.; Townsend, Harold E.

    1994-03-15

    A pressure suppression containment system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The wetwell pool includes a plenum for receiving the non-condensable gas carried with steam from the drywell following a loss-of coolant-accident (LOCA). The wetwell plenum is vented to a plenum above the GDCS pool following the LOCA for suppressing pressure rise within the containment vessel. A method of operation includes channeling steam released into the drywell following the LOCA into the wetwell pool for cooling along with the non-condensable gas carried therewith. The GDCS pool is then drained by gravity, and the wetwell plenum is vented into the GDCS plenum for channeling the non-condensable gas thereto.

  3. Pressure suppression containment system

    DOE Patents [OSTI]

    Gluntz, D.M.; Townsend, H.E.

    1994-03-15

    A pressure suppression containment system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The wetwell pool includes a plenum for receiving the non-condensable gas carried with steam from the drywell following a loss-of-coolant-accident (LOCA). The wetwell plenum is vented to a plenum above the GDCS pool following the LOCA for suppressing pressure rise within the containment vessel. A method of operation includes channeling steam released into the drywell following the LOCA into the wetwell pool for cooling along with the non-condensable gas carried therewith. The GDCS pool is then drained by gravity, and the wetwell plenum is vented into the GDCS plenum for channeling the non-condensable gas thereto. 6 figures.

  4. ZERO SUPPRESSION FOR RECORDERS

    DOE Patents [OSTI]

    Fort, W.G.S.

    1958-12-30

    A zero-suppression circuit for self-balancing recorder instruments is presented. The essential elements of the circuit include a converter-amplifier having two inputs, one for a reference voltage and the other for the signal voltage under analysis, and a servomotor with two control windings, one coupled to the a-c output of the converter-amplifier and the other receiving a reference input. Each input circuit to the converter-amplifier has a variable potentiometer and the sliders of the potentiometer are ganged together for movement by the servoinotor. The particular noveity of the circuit resides in the selection of resistance values for the potentiometer and a resistor in series with the potentiometer of the signal circuit to ensure the full value of signal voltage variation is impressed on a recorder mechanism driven by servomotor.

  5. Pressure suppression system

    DOE Patents [OSTI]

    Gluntz, Douglas M.

    1994-01-01

    A pressure suppression system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and an enclosed gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The GDCS pool includes a plenum for receiving through an inlet the non-condensable gas carried with steam from the drywell following a loss-of-coolant accident (LOCA). A condenser is disposed in the GDCS plenum for condensing the steam channeled therein and to trap the non-condensable gas therein. A method of operation includes draining the GDCS pool following the LOCA and channeling steam released into the drywell following the LOCA into the GDCS plenum for cooling along with the non-condensable gas carried therewith for trapping the gas therein.

  6. Pressure suppression system

    DOE Patents [OSTI]

    Gluntz, D.M.

    1994-10-04

    A pressure suppression system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and an enclosed gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel. The GDCS pool includes a plenum for receiving through an inlet the non-condensable gas carried with steam from the drywell following a loss-of-coolant accident (LOCA). A condenser is disposed in the GDCS plenum for condensing the steam channeled therein and to trap the non-condensable gas therein. A method of operation includes draining the GDCS pool following the LOCA and channeling steam released into the drywell following the LOCA into the GDCS plenum for cooling along with the non-condensable gas carried therewith for trapping the gas therein. 3 figs.

  7. Suppressed Charmed B Decay

    SciTech Connect (OSTI)

    Snoek, Hella Leonie; /Vrije U., Amsterdam

    2011-11-28

    This thesis describes the measurement of the branching fractions of the suppressed charmed B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decays and the non-resonant B{sup 0} {yields} D{sup (*)-} {eta}{pi}{sup +} decays in approximately 230 million {Upsilon}(4S) {yields} B{bar B} events. The data have been collected with the BABAR detector at the PEP-II B factory at the Stanford Linear Accelerator Center in California. Theoretical predictions of the branching fraction of the B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decays show large QCD model dependent uncertainties. Non-factorizing terms, in the naive factorization model, that can be calculated by QCD factorizing models have a large impact on the branching fraction of these decay modes. The predictions of the branching fractions are of the order of 10{sup -6}. The measurement of the branching fraction gives more insight into the theoretical models. In general a better understanding of QCD models will be necessary to conduct weak interaction physics at the next level. The presence of CP violation in electroweak interactions allows the differentiation between matter and antimatter in the laws of physics. In the Standard Model, CP violation is incorporated in the CKM matrix that describes the weak interaction between quarks. Relations amongst the CKM matrix elements are used to present the two relevant parameters as the apex of a triangle (Unitarity Triangle) in a complex plane. The over-constraining of the CKM triangle by experimental measurements is an important test of the Standard Model. At this moment no stringent direct measurements of the CKM angle {gamma}, one of the interior angles of the Unitarity Triangle, are available. The measurement of the angle {gamma} can be performed using the decays of neutral B mesons. The B{sup 0} {yields} D{sup (*)-} a{sub 0}{sup +} decay is sensitive to the angle {gamma} and, in comparison to the current decays that are being employed, could significantly enhance the

  8. Noise suppressing capillary separation system

    DOE Patents [OSTI]

    Yeung, Edward S.; Xue, Yongjun

    1996-07-30

    A noise-suppressing capillary separation system for detecting the real-time presence or concentration of an analyte in a sample is provided. The system contains a capillary separation means through which the analyte is moved, a coherent light source that generates a beam which is split into a reference beam and a sample beam that irradiate the capillary, and a detector for detecting the reference beam and the sample beam light that transmits through the capillary. The laser beam is of a wavelength effective to be absorbed by a chromophore in the capillary. The system includes a noise suppressing system to improve performance and accuracy without signal averaging or multiple scans.

  9. Noise suppressing capillary separation system

    DOE Patents [OSTI]

    Yeung, E.S.; Xue, Y.

    1996-07-30

    A noise-suppressing capillary separation system for detecting the real-time presence or concentration of an analyte in a sample is provided. The system contains a capillary separation means through which the analyte is moved, a coherent light source that generates a beam which is split into a reference beam and a sample beam that irradiate the capillary, and a detector for detecting the reference beam and the sample beam light that transmits through the capillary. The laser beam is of a wavelength effective to be absorbed by a chromophore in the capillary. The system includes a noise suppressing system to improve performance and accuracy without signal averaging or multiple scans. 13 figs.

  10. Fire suppression and detection equipment

    SciTech Connect (OSTI)

    E.E. Bates

    2006-01-15

    Inspection and testing guidelines go beyond the 'Code of Federal Regulation'. Title 30 of the US Code of Federal Regulations (30 CFR) contains requirements and references to national standards for inspection, testing and maintenance of fire suppression and detection equipment for mine operators. However, federal requirements have not kept pace with national standards and best practices. The article lists National Fire Protection (NFPA) standards that are referenced by the US Mine Safety and Health Administration (MSHA) in 30 CFR. It then discusses other NFPA Standards excluded from 30 CFR and explains the NFPA standard development process. 2 refs., 3 tabs., 5 photos.

  11. MEK5 suppresses osteoblastic differentiation (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    SciTech Connect Search Results Journal Article: MEK5 suppresses osteoblastic ... OSTI Identifier: 22462118 Resource Type: Journal Article Resource Relation: Journal Name: ...

  12. Ferromagnetic resonance probe liftoff suppression apparatus

    DOE Patents [OSTI]

    Davis, Thomas J.; Tomeraasen, Paul L.

    1985-01-01

    A liftoff suppression apparatus utilizing a liftoff sensing coil to sense the amount a ferromagnetic resonance probe lifts off the test surface during flaw detection and utilizing the liftoff signal to modulate the probe's field modulating coil to suppress the liftoff effects.

  13. METHOD OF SUPPRESSING GASTROINTESTINAL UREASE ACTIVITY

    DOE Patents [OSTI]

    Visek, W.J.

    1963-04-23

    This patent shows a method of increasing the growth rate of chicks. Certain diacyl substituted ureas such as alloxan, murexide, and barbituric acid are added to their feed, thereby suppressing gastrointestinal urease activity and thus promoting growth. (AEC)

  14. Suppression of Grain Boundaries in Graphene Growth on Superstructured...

    Office of Scientific and Technical Information (OSTI)

    Suppression of Grain Boundaries in Graphene Growth on Superstructured Mn-Cu(111) Surface Title: Suppression of Grain Boundaries in Graphene Growth on Superstructured Mn-Cu(111) ...

  15. Enhancement and Suppression of Photocurrent in Si Photodiodes...

    Office of Scientific and Technical Information (OSTI)

    Enhancement and Suppression of Photocurrent in Si Photodiodes by Nanoparticles and ... Title: Enhancement and Suppression of Photocurrent in Si Photodiodes by Nanoparticles and ...

  16. Benchmark enclosure fire suppression experiments - phase 1 test report.

    SciTech Connect (OSTI)

    Figueroa, Victor G.; Nichols, Robert Thomas; Blanchat, Thomas K.

    2007-06-01

    A series of fire benchmark water suppression tests were performed that may provide guidance for dispersal systems for the protection of high value assets. The test results provide boundary and temporal data necessary for water spray suppression model development and validation. A review of fire suppression in presented for both gaseous suppression and water mist fire suppression. The experimental setup and procedure for gathering water suppression performance data are shown. Characteristics of the nozzles used in the testing are presented. Results of the experiments are discussed.

  17. Traveling-wave device with mass flux suppression (Patent) | DOEPatents

    Office of Scientific and Technical Information (OSTI)

    Traveling-wave device with mass flux suppression Title: Traveling-wave device with mass flux suppression A traveling-wave device is provided with the conventional moving pistons ...

  18. Pulse compression and prepulse suppression apparatus

    DOE Patents [OSTI]

    Dane, Clifford B.; Hackel, Lloyd A.; George, Edward V.; Miller, John L.; Krupke, William F.

    1993-01-01

    A pulse compression and prepulse suppression apparatus (10) for time compressing the output of a laser (14). A pump pulse (46) is separated from a seed pulse (48) by a first polarized beam splitter (20) according to the orientation of a half wave plate (18). The seed pulse (48) is directed into an SBS oscillator (44) by two plane mirrors (22, 26) and a corner mirror (24), the corner mirror (24) being movable to adjust timing. The pump pulse (46) is directed into an SBS amplifier 34 wherein SBS occurs. The seed pulse (48), having been propagated from the SBS oscillator (44), is then directed through the SBS amplifier (34) wherein it sweeps the energy of the pump pulse (46) out of the SBS amplifier (34) and is simultaneously compressed, and the time compressed pump pulse (46) is emitted as a pulse output (52). A second polarized beam splitter (38) directs any undepleted pump pulse 58 away from the SBS oscillator (44).

  19. Passive runaway electron suppression in tokamak disruptions

    SciTech Connect (OSTI)

    Smith, H. M.; Helander, P.

    2013-07-15

    Runaway electrons created in disruptions pose a serious problem for tokamaks with large current. It would be desirable to have a runaway electron suppression method which is passive, i.e., a method that does not rely on an uncertain disruption prediction system. One option is to let the large electric field inherent in the disruption drive helical currents in the wall. This would create ergodic regions in the plasma and increase the runaway losses. Whether these regions appear at a suitable time and place to affect the formation of the runaway beam depends on disruption parameters, such as electron temperature and density. We find that it is difficult to ergodize the central plasma before a beam of runaway current has formed. However, the ergodic outer region will make the Ohmic current profile contract, which can lead to instabilities that yield large runaway electron losses.

  20. Pulse compression and prepulse suppression apparatus

    DOE Patents [OSTI]

    Dane, C.B.; Hackel, L.A.; George, E.V.; Miller, J.L.; Krupke, W.F.

    1993-11-09

    A pulse compression and prepulse suppression apparatus (10) for time compressing the output of a laser (14). A pump pulse (46) is separated from a seed pulse (48) by a first polarized beam splitter (20) according to the orientation of a half wave plate (18). The seed pulse (48) is directed into an SBS oscillator (44) by two plane mirrors (22, 26) and a corner mirror (24), the corner mirror (24) being movable to adjust timing. The pump pulse (46) is directed into an SBS amplifier 34 wherein SBS occurs. The seed pulse (48), having been propagated from the SBS oscillator (44), is then directed through the SBS amplifier (34) wherein it sweeps the energy of the pump pulse (46) out of the SBS amplifier (34) and is simultaneously compressed, and the time compressed pump pulse (46) is emitted as a pulse output (52). A second polarized beam splitter (38) directs any undepleted pump pulse 58 away from the SBS oscillator (44).

  1. SUPPRESSION OF STAR FORMATION IN NGC 1266

    SciTech Connect (OSTI)

    Alatalo, Katherine; Lanz, Lauranne; Bitsakis, Theodoros; Appleton, Philip N.; Ogle, Patrick M.; Lacy, Mark; Lonsdale, Carol J.; Nyland, Kristina; Meier, David S.; Cales, Sabrina L.; Chang, Philip; Davis, Timothy A.; De Zeeuw, P. T.; Martn, Sergio

    2015-01-01

    NGC 1266 is a nearby lenticular galaxy that harbors a massive outflow of molecular gas powered by the mechanical energy of an active galactic nucleus (AGN). It has been speculated that such outflows hinder star formation (SF) in their host galaxies, providing a form of feedback to the process of galaxy formation. Previous studies, however, indicated that only jets from extremely rare, high-power quasars or radio galaxies could impart significant feedback on their hosts. Here we present detailed observations of the gas and dust continuum of NGC 1266 at millimeter wavelengths. Our observations show that molecular gas is being driven out of the nuclear region at M-dot {sub out}?110 M{sub ?} yr{sup 1}, of which the vast majority cannot escape the nucleus. Only 2 M {sub ?} yr{sup 1} is actually capable of escaping the galaxy. Most of the molecular gas that remains is very inefficient at forming stars. The far-infrared emission is dominated by an ultra-compact (? 50 pc) source that could either be powered by an AGN or by an ultra-compact starburst. The ratio of the SF surface density (?{sub SFR}) to the gas surface density (?{sub H{sub 2}}) indicates that SF is suppressed by a factor of ?50 compared to normal star-forming galaxies if all gas is forming stars, and ?150 for the outskirt (98%) dense molecular gas if the central region is powered by an ultra-compact starburst. The AGN-driven bulk outflow could account for this extreme suppression by hindering the fragmentation and gravitational collapse necessary to form stars through a process of turbulent injection. This result suggests that even relatively common, low-power AGNs are able to alter the evolution of their host galaxies as their black holes grow onto the M-? relation.

  2. Methods for suppressing isomerization of olefin metathesis products

    DOE Patents [OSTI]

    Firth, Bruce E.; Kirk, Sharon E.; Gavaskar, Vasudeo S.

    2015-09-22

    A method for suppressing isomerization of an olefin metathesis product produced in a metathesis reaction includes adding an isomerization suppression agent to a mixture that includes the olefin metathesis product and residual metathesis catalyst from the metathesis reaction under conditions that are sufficient to passivate at least a portion of the residual metathesis catalyst. The isomerization suppression agent is phosphorous acid, a phosphorous acid ester, phosphinic acid, a phosphinic acid ester or combinations thereof. Methods of refining natural oils are described.

  3. Suppress Carrier Recombination by Introducing Defects: The Case...

    Office of Scientific and Technical Information (OSTI)

    The Case of Si Solar Cell Citation Details In-Document Search Title: Suppress Carrier Recombination by Introducing Defects: The Case of Si Solar Cell Authors: Liu, Yuanyue ; ...

  4. Mechanisms Contributing to Suppressed Precipitation in Mt. Hua...

    Office of Scientific and Technical Information (OSTI)

    Consistent with the increase of air pollution in these regions, it has been argued that the precipitation trend is linked to aerosol microphysical effect on suppressing warm rain. ...

  5. A spray-suppression model for turbulent combustion

    SciTech Connect (OSTI)

    DESJARDIN,PAUL E.; TIESZEN,SHELDON R.; GRITZO,LOUIS A.

    2000-02-14

    A spray-suppression model that captures the effects of liquid suppressant on a turbulent combusting flow is developed and applied to a turbulent diffusion flame with water spray suppression. The spray submodel is based on a stochastic separated flow approach that accounts for the transport and evaporation of liquid droplets. Flame extinguishment is accounted for by using a perfectly stirred reactor (PSR) submodel of turbulent combustion. PSR pre-calculations of flame extinction times are determined using CHEMKIN and are compared to local turbulent time scales of the flow to determine if local flame extinguishment has occurred. The PSR flame extinguishment and spray submodels are incorporated into Sandia's flow fire simulation code, VULCAN, and cases are run for the water spray suppression studies of McCaffrey for turbulent hydrogen-air jet diffusion flames. Predictions of flame temperature decrease and suppression efficiency are compared to experimental data as a function of water mass loading using three assumed values of drop sizes. The results show that the suppression efficiency is highly dependent on the initial droplet size for a given mass loading. A predicted optimal suppression efficiency was observed for the smallest class of droplets while the larger drops show increasing suppression efficiency with increasing mass loading for the range of mass loadings considered. Qualitative agreement to the experiment of suppression efficiency is encouraging, however quantitative agreement is limited due to the uncertainties in the boundary conditions of the experimental data for the water spray.

  6. Suppressed-fission ICF hybrid reactor

    SciTech Connect (OSTI)

    Hogan, W.J.; Meier, W.R.

    1986-05-20

    A suppressed-fission ICF hybrid reactor has been designed to maximize the production of /sup 233/U. In this design, Be is used as a neutron multiplier. An annular array of Be columns surrounds the fusion pulse inside the reaction chember. The Be columns consist of short cylinders of Be joined together with steel snap rings. Vertical holes in the Be carry liquid lithium coolant and steel-clad thorium fuel pins. The lithium coolant is supplied at the top of the chamber, traverses through the Be columns and exits at the bottom. The columns are attached to top and bottom plates in such a way as to tolerate radiation-induced swelling and the vibrations resulting from each fusion pulse. A thin (10 cm) liquid Li fall region protects the Be columns from direct exposure to the X-rays and debris emitted by the fuel capsule. A neutronics study of this design indicates that the specific production of /sup 233/U fuel is increased by operating at relatively large thorium volume fractions. A design at a fertile fuel fraction of 30 vol % produces a total breeding ratio of over 2.1. The /sup 6/Li to /sup 7/Li ratio is adjusted to keep the tritium breeding ratio at about 1.0. In such a reactor, about 3400 kg of /sup 233/U can be produced per full power year at a fusion power level of 800 MW. Reactor support ratios greater than 13 can be achieved, leading to beneficial results even if the fusion reactor cost is significantly greater than that of a fission reactor.

  7. Application of phase coherent transform to cloud clutter suppression

    SciTech Connect (OSTI)

    Ng, L.C.

    1994-11-15

    This paper describes a tracking algorithm using frame-to-frame correlation with frequency domain clutter suppression. Clutter suppression was mechanized via a `Phase Coherent Transform` (PCT) approach. This approach was applied to explore the feasibility of tracking a post-boost rocket from a low earth orbit satellite with real cloud background data. Simulation results show that the PCT/correlation tracking algorithm can perform satisfactorily at signal-to-clutter ratio (SCR) as low as 5 or 7 dB.

  8. Methods for suppressing isomerization of olefin metathesis products

    DOE Patents [OSTI]

    Firth, Bruce E.; Kirk, Sharon E.

    2015-10-27

    A method for suppressing isomerization of an olefin metathesis product produced in a metathesis reaction includes adding an isomerization suppression agent that includes nitric acid to a mixture that includes the olefin metathesis product and residual metathesis catalyst from the metathesis reaction under conditions that are sufficient to passivate at least a portion of the residual metathesis catalyst. Methods of refining a natural oil are described.

  9. Mode of ATM-dependent suppression of chromosome translocation

    SciTech Connect (OSTI)

    Yamauchi, Motohiro; Suzuki, Keiji; Oka, Yasuyoshi; Suzuki, Masatoshi; Kondo, Hisayoshi; Yamashita, Shunichi

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer We addressed how ATM suppresses frequency of chromosome translocation. Black-Right-Pointing-Pointer We found ATM/p53-dependent G1 checkpoint suppresses translocation frequency. Black-Right-Pointing-Pointer We found ATM and DNA-PKcs function in a common pathway to suppress translocation. -- Abstract: It is well documented that deficiency in ataxia telangiectasia mutated (ATM) protein leads to elevated frequency of chromosome translocation, however, it remains poorly understood how ATM suppresses translocation frequency. In the present study, we addressed the mechanism of ATM-dependent suppression of translocation frequency. To know frequency of translocation events in a whole genome at once, we performed centromere/telomere FISH and scored dicentric chromosomes, because dicentric and translocation occur with equal frequency and by identical mechanism. By centromere/telomere FISH analysis, we confirmed that chemical inhibition or RNAi-mediated knockdown of ATM causes 2 to 2.5-fold increase in dicentric frequency at first mitosis after 2 Gy of gamma-irradiation in G0/G1. The FISH analysis revealed that ATM/p53-dependent G1 checkpoint suppresses dicentric frequency, since RNAi-mediated knockdown of p53 elevated dicentric frequency by 1.5-fold. We found ATM also suppresses dicentric occurrence independently of its checkpoint role, as ATM inhibitor showed additional effect on dicentric frequency in the context of p53 depletion and Chk1/2 inactivation. Epistasis analysis using chemical inhibitors revealed that ATM kinase functions in the same pathway that requires kinase activity of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to suppress dicentric frequency. From the results in the present study, we conclude that ATM minimizes translocation frequency through its commitment to G1 checkpoint and DNA double-strand break repair pathway that requires kinase activity of DNA-PKcs.

  10. Arsenite suppression of BMP signaling in human keratinocytes

    SciTech Connect (OSTI)

    Phillips, Marjorie A.; Qin, Qin; Hu, Qin; Zhao, Bin; Rice, Robert H.

    2013-06-15

    Arsenic, a human skin carcinogen, suppresses differentiation of cultured keratinocytes. Exploring the mechanism of this suppression revealed that BMP-6 greatly increased levels of mRNA for keratins 1 and 10, two of the earliest differentiation markers expressed, a process prevented by co-treatment with arsenite. BMP also stimulated, and arsenite suppressed, mRNA for FOXN1, an important transcription factor driving early keratinocyte differentiation. Keratin mRNAs increased slowly after BMP-6 addition, suggesting they are indirect transcriptional targets. Inhibition of Notch1 activation blocked BMP induction of keratins 1 and 10, while FOXN1 induction was largely unaffected. Supporting a requirement for Notch1 signaling in keratin induction, BMP increased levels of activated Notch1, which was blocked by arsenite. BMP also greatly decreased active ERK, while co-treatment with arsenite maintained active ERK. Inhibition of ERK signaling mimicked BMP by inducing keratin and FOXN1 mRNAs and by increasing active Notch1, effects blocked by arsenite. Of 6 dual-specificity phosphatases (DUSPs) targeting ERK, two were induced by BMP unless prevented by simultaneous exposure to arsenite and EGF. Knockdown of DUSP2 or DUSP14 using shRNAs greatly reduced FOXN1 and keratins 1 and 10 mRNA levels and their induction by BMP. Knockdown also decreased activated Notch1, keratin 1 and keratin 10 protein levels, both in the presence and absence of BMP. Thus, one of the earliest effects of BMP is induction of DUSPs, which increases FOXN1 transcription factor and activates Notch1, both required for keratin gene expression. Arsenite prevents this cascade by maintaining ERK signaling, at least in part by suppressing DUSP expression. - Highlights: • BMP induces FOXN1 transcription. • BMP induces DUSP2 and DUSP14, suppressing ERK activation. • Arsenite suppresses levels of phosphorylated Smad1/5 and FOXN1 and DUSP mRNA. • These actions rationalize arsenite suppression of keratinocyte

  11. A simplified model of decontamination by BWR steam suppression pools

    SciTech Connect (OSTI)

    Powers, D.A.

    1997-05-01

    Phenomena that can decontaminate aerosol-laden gases sparging through steam suppression pools of boiling water reactors during reactor accidents are described. Uncertainties in aerosol properties, aerosol behavior within gas bubbles, and bubble behavior in plumes affect predictions of decontamination by steam suppression pools. Uncertainties in the boundary and initial conditions that are dictated by the progression of severe reactor accidents and that will affect predictions of decontamination by steam suppression pools are discussed. Ten parameters that characterize boundary and initial condition uncertainties, nine parameters that characterize aerosol property and behavior uncertainties, and eleven parameters that characterize uncertainties in the behavior of bubbles in steam suppression pools are identified. Ranges for the values of these parameters and subjective probability distributions for parametric values within the ranges are defined. These uncertain parameters are used in Monte Carlo uncertainty analyses to develop uncertainty distributions for the decontamination that can be achieved by steam suppression pools and the size distribution of aerosols that do emerge from such pools. A simplified model of decontamination by steam suppression pools is developed by correlating features of the uncertainty distributions for total decontamination factor, DF(total), mean size of emerging aerosol particles, d{sub p}, and the standard deviation of the emerging aerosol size distribution, {sigma}, with pool depth, H. Correlations of the median values of the uncertainty distributions are suggested as the best estimate of decontamination by suppression pools. Correlations of the 10 percentile and 90 percentile values of the uncertainty distributions characterize the uncertainty in the best estimates. 295 refs., 121 figs., 113 tabs.

  12. Kink instability suppression with stochastic cooling pickup and kicker

    SciTech Connect (OSTI)

    Hao Y.; Blaskiewicz, M.; Litvinenko, V.N.; Ptitsyn, V.

    2012-05-20

    The kink instability is one of the major beam dynamics issues of the linac-ring based electron ion collider. This head-tail type instability arises from the oscillation of the electron beam inside the opposing ion beam. It must be suppressed to achieve the desired luminosity. There are various ways to suppress the instability, such as tuning the chromaticity in the ion ring or by a dedicated feedback system of the electron beam position at IP, etc. However, each method has its own limitation. In this paper, we will discuss an alternative opportunity of suppressing the kink instability of the proposed eRHIC at BNL using the existing pickup-kicker system of the stochastic cooling system in RHIC.

  13. Experience with IBS-suppression lattice in RHIC

    SciTech Connect (OSTI)

    Litvinenko,V.N.; Luo, Y.; Ptitsyn, V.; Satogata, T.; Tepikian, S.; Bai, M.; Bruno, D.; Cameron, P.; Connolly, R.; Della Penna, A.; Drees, A.; Fedotov, A.; Ganetis, G.; Hoff, L.; Louie, W.; Malitsky, N.; Marr, G.; Marusic, A.; Montag, C.; Pilat, F.; Roser, T.; Trbojevic, D.; Tsoupas, N.

    2008-06-23

    An intra-beam scattering (IBS) is the limiting factor of the luminosity lifetime for RHIC operating with heavy ions. In order to suppress the IBS we designed and implemented new lattice with higher betatron tunes. This lattice had been developed during last three years and had been used for gold ions in yellow ring of the RHIC during d-Au part of the RHIC Run-8. The use of this lattice allowed both significant increases in the luminosity lifetime and the luminosity levels via reduction of beta-stars in the IPS. In this paper we report on the development, the tests and the performance of IBS-suppression lattice in RHIC, including the resulting increases in the peak and the average luminosity. We also report on our plans for future steps with the IBS suppression.

  14. IBS suppression lattice in RHIC: theory and experimental verification

    SciTech Connect (OSTI)

    Fedotov,A.V.; Bai, M.; Bruno, D.; Cameron, P.; Connolly, R.; Cupolo, J.; Della Penna, A.; Drees, A.; Fischer, W.; Ganetis, G.; Hoff, L.; Litvinenko, V.N.; Louie, W.; Luo, Y.; Malitsky, N.; Marr, G.; Marusic, A.; Montag, C.; Ptitsyn, V.; Roser, T.; Satogata, T.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.

    2008-08-25

    Intra-beam scattering (IBS) is the limiting factor of the luminosity lifetime for Relativistic Heavy Ion Collider (RHIC) operation with heavy ions. Over the last few years the process of IBS was carefully studied in RHIC with dedicated IBS measurements and their comparison with the theoretical models. A new lattice was recently designed and implemented in RHIC to suppress transverse IBS growth, which lowered the average arc dispersion by about 20% [1]. This lattice became operational during RHIC Run-8. We review the IBS suppression mechanism, IBS measurements before and after the lattice change, and comparisons with predictions.

  15. Fission-suppressed hybrid reactor: the fusion breeder

    SciTech Connect (OSTI)

    Moir, R.W.; Lee, J.D.; Coops, M.S.

    1982-12-01

    Results of a conceptual design study of a /sup 233/U-producing fusion breeder are presented. The majority of the study was devoted to conceptual design and evaluation of a fission-suppressed blanket and to fuel cycle issues such as fuel reprocessing, fuel handling, and fuel management. Studies in the areas of fusion engineering, reactor safety, and economics were also performed.

  16. Suppression Pool Mixing and Condensation Tests in PUMA Facility

    SciTech Connect (OSTI)

    Ling Cheng; Kyoung Suk Woo; Mamoru Ishii; Jaehyok Lim; Han, James

    2006-07-01

    Condensation of steam with non-condensable in the form of jet flow or bubbly flow inside the suppression pool is an important phenomenon on determining the containment pressure of a passively safe boiling water reactor. 32 cases of pool mixing and condensation test have been performed in Purdue University Multi-Dimensional Integral Test Assembly (PUMA) facility under the sponsor of the U.S. Nuclear Regulatory Commission to investigate thermal stratification and pool mixing inside the suppression pool during the reactor blowdown period. The test boundary conditions, such as the steam flow rate, the noncondensable gas flow rate, the initial water temperature, the pool initial pressure and the vent opening submergence depth, which covers a wide range of prototype (SBWR-600) conditions during Loss of Coolant Accident (LOCA) were obtained from the RELAP5 calculation. The test results show that steam is quickly condensed at the exit of the vent opening. For pure steam injection or low noncondensable injection cases, only the portion above the vent opening in the suppression pool is heated up by buoyant plumes. The water below the vent opening can be heated up slowly through conduction. The test results also show that the degree of thermal stratification in suppression pool is affected by the vent opening submergence depth, the pool initial pressure and the steam injection rate. And it is slightly affected by the initial water temperature. From these tests it is concluded that the pool mixing is strongly affected by the noncondensable gas flow rate. (authors)

  17. Using multiple perspectives to suppress information and complexity

    SciTech Connect (OSTI)

    Kelsey, R.L. |; Webster, R.B.; Hartley, R.T.

    1998-09-01

    Dissemination of battlespace information involves getting information to particular warfighters that is both useful and in a form that facilitates the tasks of those particular warfighters. There are two issues which motivate this problem of dissemination. The first issue deals with disseminating pertinent information to a particular warfighter. This can be thought of as information suppression. The second issue deals with facilitating the use of the information by tailoring the computer interface to the specific tasks of an individual warfighter. This can be thought of as interface complexity suppression. This paper presents a framework for suppressing information using an object-based knowledge representation methodology. This methodology has the ability to represent knowledge and information in multiple perspectives. Information can be suppressed by creating a perspective specific to an individual warfighter. In this way, only the information pertinent and useful to a warfighter is made available to that warfighter. Information is not removed, lost, or changed, but spread among multiple perspectives. Interface complexity is managed in a similar manner. Rather than have one generalized computer interface to access all information, the computer interface can be divided into interface elements. Interface elements can then be selected and arranged into a perspective-specific interface. This is done in a manner to facilitate completion of tasks contained in that perspective. A basic battlespace domain containing ground and air elements and associated warfighters is used to exercise the methodology.

  18. Low Dose Suppression of Neoplastic Transformation in Vitro

    SciTech Connect (OSTI)

    John Leslie Redpath

    2012-05-01

    This grant was to study the low dose suppression of neoplastic transformation in vitro and the shape of the dose-response curve at low doses and dose-rates of ionizing radiation. Previous findings had indicated a suppression of transformation at dose <10cGy of low-LET radiation when delivered at high dose-rate. The present study indicates that such suppression extends out to doses in excess of 100cGy when the dose (from I-125 photons) is delivered at dose-rates as low as 0.2 mGy/min and out to in excess of {approx}25cGy the highest dose studied at the very low dose-rate of 0.5 mGy/day. We also examined dose-rate effects for high energy protons (which are a low-LET radiation) and suppression was evident below {approx}10cGy for high dose-rate delivery and at least out to 50cGy for low dose-rate (20cGy/h) delivery. Finally, we also examined the effect of low doses of 1 GeV/n iron ions (a high-LET radiation) delivered at high dose-rate on transformation at low doses and found a suppression below {approx}10cGy that could be attributable to an adaptive response in bystander cells induced by the associated low-LET delta rays. These results have implications for cancer risk assessment at low doses.

  19. Technology Assessment of Dust Suppression Techniques applied During Structural Demolition

    SciTech Connect (OSTI)

    Boudreaux, J.F.; Ebadian, M.A.; Dua, S.K.

    1997-08-06

    Hanford, Fernald, Savannah River, and other sites are currently reviewing technologies that can be implemented to demolish buildings in a cost-effective manner. In order to demolish a structure and, at the same time, minimize the amount of dust generated by a given technology, an evaluation must be conducted to choose the most appropriate dust suppression technology. Thus, the purpose of this research, which was conducted by the Hemispheric Center for Environmental Technology (HCET) at Florida International University (FIU), was to perform an experimental study of dust aerosol abatement (dust suppression) methods as applied to nuclear D and D. This experimental study specifically targeted the problem of dust suppression during demolition. The resulting data were used in the development of mathematical correlations that can be applied to structural demolition. In the Fiscal Year 1996 (FY96), the effectiveness of different dust suppressing agents was investigated for different types of concrete blocks. Initial tests were conducted in a broad particle size range. In Fiscal Year 1997 (FY97), additional tests were performed in the size range in which most of the particles were detected. Since particle distribution is an important parameter for predicting deposition in various compartments of the human respiratory tract, various tests were aimed at determining the particle size distribution of the airborne dust particles. The effectiveness of dust suppressing agents for particles of various size was studied. Instead of conducting experiments on various types of blocks, it was thought prudent to carry out additional tests on blocks of the same type. Several refinements were also incorporated in the test procedures and data acquisition system used in FY96.

  20. Suppression of quantum chaos in a quantum computer hardware

    SciTech Connect (OSTI)

    Lages, J.; Shepelyansky, D. L. [Laboratoire de Physique Theorique, UMR 5152 du CNRS, Universite Paul Sabatier, 31062 Toulouse Cedex 4 (France)

    2006-08-15

    We present numerical and analytical studies of a quantum computer proposed by the Yamamoto group in Phys. Rev. Lett. 89, 017901 (2002). The stable and quantum chaos regimes in the quantum computer hardware are identified as a function of magnetic field gradient and dipole-dipole couplings between qubits on a square lattice. It is shown that a strong magnetic field gradient leads to suppression of quantum chaos.

  1. 'Catch and Suppress' Control of Instabilities in High Performance

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

    Fusion Plasmas | U.S. DOE Office of Science (SC) 'Catch and Suppress' Control of Instabilities in High Performance Fusion Plasmas Fusion Energy Sciences (FES) FES Home About Research Facilities Science Highlights Benefits of FES Funding Opportunities Fusion Energy Sciences Advisory Committee (FESAC) Community Resources Contact Information Fusion Energy Sciences U.S. Department of Energy SC-24/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-4941 F: (301)

  2. Suppression of Rayleigh Taylor instability in strongly coupled plasmas

    SciTech Connect (OSTI)

    Das, Amita; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2014-06-15

    The Rayleigh Taylor instability in a strongly coupled plasma medium has been investigated using the equations of generalized hydrodynamics. It is demonstrated that the visco-elasticity of the strongly coupled medium due to strong inter particle correlations leads to a suppression of the Rayleigh Taylor instability unless certain threshold conditions are met. The relevance of these results to experiments on laser compression of matter to high densities including those related to inertial confinement fusion using lasers has also been shown.

  3. Suppression of auger recombination in ""giant"" core/shell nanocrystals

    SciTech Connect (OSTI)

    Garcia Santamaria, Florencio; Vela, Javier; Schaller, Richard D; Hollingsworth, Jennifer A; Klimov, Victor I; Chen, Yongfen

    2009-01-01

    Many potential applications of semiconductor nanocrystals are hindered by nonradiative Auger recombination wherein the electron-hole (exciton) recombination energy is transferred to a third charge carrier. This process severely limits the lifetime and bandwidth of optical gain, leads to large nonradiative losses in light emitting diodes and photovoltaic cells, and is believed to be responsible for intermittency ('blinking') of emission from single nanocrystals. The development of nanostructures in which Auger recombination is suppressed has been a longstanding goal in colloidal nanocrystal research. Here, we demonstrate that such suppression is possible using so-called 'giant' nanocrystals that consist of a small CdSe core and a thick CdS shell. These nanostructures exhibit a very long biexciton lifetime ({approx}10 ns) that is likely dominated by radiative decay instead of non-radiative Auger recombination. As a result of suppressed Auger recombination, even high-order multiexcitons exhibit high emission efficiencies, which allows us to demonstrate optical amplification with an extraordinarily large bandwidth (>500 me V) and record low excitation thresholds.

  4. Suppression of energetic particle driven instabilities with HHFW heating

    SciTech Connect (OSTI)

    Fredrickson, E. D.; Taylor, G.; Bertelli, N.; Darrow, D. S.; Gorelenkov, N.; Kramer, G.; Liu, D.; Crocker, N. A.; Kubota, S.; White, R.

    2015-01-01

    In plasmas in the National Spherical Torus Experiment (NSTX) [Ono et al., Nucl. Fusion 40 (2000) 557] heated with neutral beams, the beam ions typically excite Energetic Particle Modes (EPMs or fishbones), and Toroidal, Global or Compressional Alfvén Eigenmodes (TAE, GAE, CAE). These modes can redistribute the energetic beam ions, altering the beam driven current profile and the plasma heating profile, or they may affect electron thermal transport or cause losses of the beam ions. In this paper we present experimental results where these instabilities, driven by the super-thermal beam ions, are suppressed with the application of High Harmonic Fast Wave heating.

  5. Suppression of energetic particle driven instabilities with HHFW heating

    SciTech Connect (OSTI)

    Fredrickson, E. D.; Taylor, G.; Bertelli, N.; Darrow, D. S.; Gorelenkov, N.; Kramer, G.; Liu, D.; Crocker, N. A.; Kubota, S.; White, R.

    2015-01-01

    In plasmas in the National Spherical Torus Experiment (NSTX) [Ono et al., Nucl. Fusion 40 (2000) 557] heated with neutral beams, the beam ions typically excite Energetic Particle Modes (EPMs or fishbones), and Toroidal, Global or Compressional Alfvn Eigenmodes (TAE, GAE, CAE). These modes can redistribute the energetic beam ions, altering the beam driven current profile and the plasma heating profile, or they may affect electron thermal transport or cause losses of the beam ions. In this paper we present experimental results where these instabilities, driven by the super-thermal beam ions, are suppressed with the application of High Harmonic Fast Wave heating.

  6. Inhibiting voltage suppression in lithium/fluorinated carbon batteries

    SciTech Connect (OSTI)

    Shia, G.A.; Nalewajek, D.; Pyszczek, M.F.

    1988-12-13

    This patent describes a lithium/fluorinated carbon battery having a reduced initial voltage suppression which comprises the incorporation in the battery cathode of fluorinated carbon which has been reacted with a compound selected from the group consisting of a Group IA metal-alkyl compound and a Group IA metal-aryl compound, which Group IA metal-aryl compound has at least 10 carbon atoms, until surface fluorine on the fluorinated carbon has been stripped and alkyl or aryl groups from the Group IA metal-alkyl compound or Group IA metal-aryl compound are substituted for surface fluorine atoms.

  7. Concrete Dust Suppression System. Innovative Technology Summary Report

    SciTech Connect (OSTI)

    1998-12-01

    The improved technology is a water-based dust suppression system for controlling concrete dust generated by demolition equipment, in this case a demolition ram. This demonstration was performed to assess the effectiveness of this system to (1) minimize the amount of water used to suppress potentially contaminated dust, (2) focus the water spray on the dust-generating source and (3) minimize the dust cloud generated by the demolition activity. The technology successfully reduced the water required by a factor of eight compared to the traditional (baseline) method, controlled the dust generated, and permitted a reduction in the work force. The water spray can be focused at the ram point, but it is affected by wind. Prior to the use of this dust control system, dust generated by the demolition ram was controlled manually by spraying with fire hoses (the baseline technology). The improved technology is 18% less expensive than the baseline technology for the conditions and parameters of this demonstration, however, the automated system can save up to 80% versus the baseline whenever waste water treatment costs are considered. For demolishing one high-walled room and a long slab with a total of 413 m{sup 3} (14,580 ft{sup 3}) of concrete, the savings are $105,000 (waste water treatment included). The improved technology reduced the need for water consumption and treatment by about 88% which results in most of the savings.

  8. Reliability study of an emerging fire suppression system

    SciTech Connect (OSTI)

    Miller, David A.; Rossati, Lyric M.; Fritz, Nathan K.; Cournoyer, Michael E.; Granzow, Howard N.

    2015-02-07

    Self-contained fire extinguishers are a robust, reliable and minimally invasive means of fire suppression for gloveboxes. Plutonium gloveboxes are known to present harsh environmental conditions for polymer materials, these include radiation damage and chemical exposure, both of which tend to degrade the lifetime of engineered polymer components. The primary component of interest in self-contained fire extinguishers is the nylon 6-6 machined tube that comprises the main body of the system.Thermo-mechanical modeling and characterization of nylon 6-6 for use in plutonium glovebox applications has been carried out. Data has been generated regarding property degradation leading to poor, or reduced, engineering performance of nylon 6-6 components. In this study, nylon 6-6 tensile specimens conforming to the casing of self-contained fire extinguisher systems have been exposed to hydrochloric, nitric, and sulfuric acids. This information was used to predict the performance of a load bearing engineering component comprised of nylon 6-6 and designed to operate in a consistent manner over a specified time period. The study provides a fundamental understanding of the engineering performance of the fire suppression system and the effects of environmental degradation due to acid exposure on engineering performance. Data generated help identify the limitations of self-contained fire extinguishers. No critical areas of concern for plutonium glovebox applications of nylon 6-6 have been identified when considering exposure to mineral acid.

  9. Reliability study of an emerging fire suppression system

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

    Miller, David A.; Rossati, Lyric M.; Fritz, Nathan K.; Cournoyer, Michael E.; Granzow, Howard N.

    2015-02-07

    Self-contained fire extinguishers are a robust, reliable and minimally invasive means of fire suppression for gloveboxes. Plutonium gloveboxes are known to present harsh environmental conditions for polymer materials, these include radiation damage and chemical exposure, both of which tend to degrade the lifetime of engineered polymer components. The primary component of interest in self-contained fire extinguishers is the nylon 6-6 machined tube that comprises the main body of the system.Thermo-mechanical modeling and characterization of nylon 6-6 for use in plutonium glovebox applications has been carried out. Data has been generated regarding property degradation leading to poor, or reduced, engineering performancemore » of nylon 6-6 components. In this study, nylon 6-6 tensile specimens conforming to the casing of self-contained fire extinguisher systems have been exposed to hydrochloric, nitric, and sulfuric acids. This information was used to predict the performance of a load bearing engineering component comprised of nylon 6-6 and designed to operate in a consistent manner over a specified time period. The study provides a fundamental understanding of the engineering performance of the fire suppression system and the effects of environmental degradation due to acid exposure on engineering performance. Data generated help identify the limitations of self-contained fire extinguishers. No critical areas of concern for plutonium glovebox applications of nylon 6-6 have been identified when considering exposure to mineral acid.« less

  10. Short wavelength limits of current shot noise suppression

    SciTech Connect (OSTI)

    Nause, Ariel; Dyunin, Egor; Gover, Avraham

    2014-08-15

    Shot noise in electron beam was assumed to be one of the features beyond control of accelerator physics. Current results attained in experiments at Accelerator Test Facility in Brookhaven and Linac Coherent Light Source in Stanford suggest that the control of the shot noise in electron beam (and therefore of spontaneous radiation and Self Amplified Spontaneous Emission of Free Electron Lasers) is feasible at least in the visible range of the spectrum. Here, we present a general linear formulation for collective micro-dynamics of e-beam noise and its control. Specifically, we compare two schemes for current noise suppression: a quarter plasma wavelength drift section and a combined drift/dispersive (transverse magnetic field) section. We examine and compare their limits of applicability at short wavelengths via considerations of electron phase-spread and the related Landau damping effect.

  11. Pressure suppression containment system for boiling water reactor

    DOE Patents [OSTI]

    Gluntz, Douglas M.; Nesbitt, Loyd B.

    1997-01-01

    A system for suppressing the pressure inside the containment of a BWR following a postulated accident. A piping subsystem is provided which features a main process pipe that communicates the wetwell airspace to a connection point downstream of the guard charcoal bed in an offgas system and upstream of the main bank of delay charcoal beds which give extensive holdup to offgases. The main process pipe is fitted with both inboard and outboard containment isolation valves. Also incorporated in the main process pipe is a low-differential-pressure rupture disk which prevents any gas outflow in this piping whatsoever until or unless rupture occurs by virtue of pressure inside this main process pipe on the wetwell airspace side of the disk exceeding the design opening (rupture) pressure differential. The charcoal holds up the radioactive species in the noncondensable gas from the wetwell plenum by adsorption, allowing time for radioactive decay before the gas is vented to the environs.

  12. Method of inhibiting voltage suppression lithium/fluorinated carbon batteries

    SciTech Connect (OSTI)

    Shia, G.A.; Friedland, D.J.

    1987-08-11

    An improved lithium/fluorinated carbon battery is described wherein the cathode comprises a blend of at least two different CF/sub x/ compositions which are derived from petroleum-based coke products which have been prepared by heat treatment at a temperature between about 800/sup 0/C and 2,0006/sup 0/C: (a) a bulk CF/sub x/ and (b) an additive CF/sub x/ and wherein from about 0.5 percent to about 50 percent of (b) is characterized as having a closed circuit voltage of at least 150 mV above the plateau voltage of the bulk CF/sub x/ and a specific capacity above 600 mAH/g. A method is also described for the elimination of suppression of the closed circuit voltage of a Li/CF/sub x/ battery during the initial part of its discharge.

  13. Suppression of energetic particle driven instabilities with HHFW heating

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

    Fredrickson, E. D.; Taylor, G.; Bertelli, N.; Darrow, D. S.; Gorelenkov, N.; Kramer, G.; Liu, D.; Crocker, N. A.; Kubota, S.; White, R.

    2015-01-01

    In plasmas in the National Spherical Torus Experiment (NSTX) [Ono et al., Nucl. Fusion 40 (2000) 557] heated with neutral beams, the beam ions typically excite Energetic Particle Modes (EPMs or fishbones), and Toroidal, Global or Compressional Alfvén Eigenmodes (TAE, GAE, CAE). These modes can redistribute the energetic beam ions, altering the beam driven current profile and the plasma heating profile, or they may affect electron thermal transport or cause losses of the beam ions. In this paper we present experimental results where these instabilities, driven by the super-thermal beam ions, are suppressed with the application of High Harmonic Fastmore » Wave heating.« less

  14. Pressure suppression containment system for boiling water reactor

    DOE Patents [OSTI]

    Gluntz, D.M.; Nesbitt, L.B.

    1997-01-21

    A system is disclosed for suppressing the pressure inside the containment of a BWR following a postulated accident. A piping subsystem is provided which features a main process pipe that communicates the wetwell airspace to a connection point downstream of the guard charcoal bed in an offgas system and upstream of the main bank of delay charcoal beds which give extensive holdup to offgases. The main process pipe is fitted with both inboard and outboard containment isolation valves. Also incorporated in the main process pipe is a low-differential-pressure rupture disk which prevents any gas outflow in this piping whatsoever until or unless rupture occurs by virtue of pressure inside this main process pipe on the wetwell airspace side of the disk exceeding the design opening (rupture) pressure differential. The charcoal holds up the radioactive species in the noncondensable gas from the wetwell plenum by adsorption, allowing time for radioactive decay before the gas is vented to the environs. 3 figs.

  15. Verification study of an emerging fire suppression system

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

    Cournoyer, Michael E.; Waked, R. Ryan; Granzow, Howard N.; Gubernatis, David C.

    2016-01-01

    Self-contained fire extinguishers are a robust, reliable and minimally invasive means of fire suppression for gloveboxes. Moreover, plutonium gloveboxes present harsh environmental conditions for polymer materials; these include radiation damage and chemical exposure, both of which tend to degrade the lifetime of engineered polymer components. Several studies have been conducted to determine the robustness of selfcontained fire extinguishers in plutonium gloveboxes in a nuclear facility, verification tests must be performed. These tests include activation and mass loss calorimeter tests. In addition, compatibility issues with chemical components of the self-contained fire extinguishers need to be addressed. Our study presents activation andmore » mass loss calorimeter test results. After extensive studies, no critical areas of concern have been identified for the plutonium glovebox application of Fire Foe™, except for glovebox operations that use large quantities of bulk plutonium or uranium metal such as metal casting and pyro-chemistry operations.« less

  16. Verification study of an emerging fire suppression system

    SciTech Connect (OSTI)

    Cournoyer, Michael E.; Waked, R. Ryan; Granzow, Howard N.; Gubernatis, David C.

    2016-01-01

    Self-contained fire extinguishers are a robust, reliable and minimally invasive means of fire suppression for gloveboxes. Moreover, plutonium gloveboxes present harsh environmental conditions for polymer materials; these include radiation damage and chemical exposure, both of which tend to degrade the lifetime of engineered polymer components. Several studies have been conducted to determine the robustness of selfcontained fire extinguishers in plutonium gloveboxes in a nuclear facility, verification tests must be performed. These tests include activation and mass loss calorimeter tests. In addition, compatibility issues with chemical components of the self-contained fire extinguishers need to be addressed. Our study presents activation and mass loss calorimeter test results. After extensive studies, no critical areas of concern have been identified for the plutonium glovebox application of Fire Foe™, except for glovebox operations that use large quantities of bulk plutonium or uranium metal such as metal casting and pyro-chemistry operations.

  17. Method and apparatus for suppressing waves in a borehole

    DOE Patents [OSTI]

    West, Phillip B.

    2005-10-04

    Methods and apparatus for suppression of wave energy within a fluid-filled borehole using a low pressure acoustic barrier. In one embodiment, a flexible diaphragm type device is configured as an open bottomed tubular structure for disposition in a borehole to be filled with a gas to create a barrier to wave energy, including tube waves. In another embodiment, an expandable umbrella type device is used to define a chamber in which a gas is disposed. In yet another embodiment, a reverse acting bladder type device is suspended in the borehole. Due to its reverse acting properties, the bladder expands when internal pressure is reduced, and the reverse acting bladder device extends across the borehole to provide a low pressure wave energy barrier.

  18. Study on higher harmonic suppression using edge filter and polished Si wafer

    SciTech Connect (OSTI)

    Gupta, R. K. Singh, Amol Modi, Mohammed H. Lodha, G. S.

    2014-04-24

    Higher harmonics contamination is a severe problem in synchrotron beamlines where grating monochromators are used. In these beamlines, absorption edge filters and critical angle mirrors are used to suppress the harmonic contaminations. In the present study, carried out using Indus-1 reflectivity beamline, a harmonic suppression characteristic of Al edge filter and polished silicon wafer are determined. It is found that the Al filter suppresses higher harmonics in 2–7% range whereas the polished silicon wafer can suppress the higher harmonics below 1%. The results of comparative study are discussed.

  19. Kalispel Non-Native Fish Suppression Project 2007 Annual Report.

    SciTech Connect (OSTI)

    Wingert, Michele; Andersen, Todd

    2008-11-18

    Non-native salmonids are impacting native salmonid populations throughout the Pend Oreille Subbasin. Competition, hybridization, and predation by non-native fish have been identified as primary factors in the decline of some native bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarki lewisi) populations. In 2007, the Kalispel Natural Resource Department (KNRD) initiated the Kalispel Nonnative Fish Suppression Project. The goal of this project is to implement actions to suppress or eradicate non-native fish in areas where native populations are declining or have been extirpated. These projects have previously been identified as critical to recovering native bull trout and westslope cutthroat trout (WCT). Lower Graham Creek was invaded by non-native rainbow (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis) after a small dam failed in 1991. By 2003, no genetically pure WCT remained in the lower 700 m of Graham Creek. Further invasion upstream is currently precluded by a relatively short section of steep, cascade-pool stepped channel section that will likely be breached in the near future. In 2008, a fish management structure (barrier) was constructed at the mouth of Graham Creek to preclude further invasion of non-native fish into Graham Creek. The construction of the barrier was preceded by intensive electrofishing in the lower 700 m to remove and relocate all captured fish. Westslope cutthroat trout have recently been extirpated in Cee Cee Ah Creek due to displacement by brook trout. We propose treating Cee Cee Ah Creek with a piscicide to eradicate brook trout. Once eradication is complete, cutthroat trout will be translocated from nearby watersheds. In 2004, the Washington Department of Fish and Wildlife (WDFW) proposed an antimycin treatment within the subbasin; the project encountered significant public opposition and was eventually abandoned. However, over the course of planning this 2004 project, little public

  20. Quadrature mixture LO suppression via DSW DAC noise dither

    DOE Patents [OSTI]

    Dubbert, Dale F. (Cedar Crest, NM); Dudley, Peter A. (Albuquerque, NM)

    2007-08-21

    A Quadrature Error Corrected Digital Waveform Synthesizer (QECDWS) employs frequency dependent phase error corrections to, in effect, pre-distort the phase characteristic of the chirp to compensate for the frequency dependent phase nonlinearity of the RF and microwave subsystem. In addition, the QECDWS can employ frequency dependent correction vectors to the quadrature amplitude and phase of the synthesized output. The quadrature corrections cancel the radars' quadrature upconverter (mixer) errors to null the unwanted spectral image. A result is the direct generation of an RF waveform, which has a theoretical chirp bandwidth equal to the QECDWS clock frequency (1 to 1.2 GHz) with the high Spurious Free Dynamic Range (SFDR) necessary for high dynamic range radar systems such as SAR. To correct for the problematic upconverter local oscillator (LO) leakage, precision DC offsets can be applied over the chirped pulse using a pseudo-random noise dither. The present dither technique can effectively produce a quadrature DC bias which has the precision required to adequately suppress the LO leakage. A calibration technique can be employed to calculate both the quadrature correction vectors and the LO-nulling DC offsets using the radar built-in test capability.

  1. Suppressing spectral diffusion of emitted photons with optical pulses

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

    Fotso, H. F.; Feiguin, A. E.; Awschalom, D. D.; Dobrovitski, V. V.

    2016-01-22

    In many quantum architectures the solid-state qubits, such as quantum dots or color centers, are interfaced via emitted photons. However, the frequency of photons emitted by solid-state systems exhibits slow uncontrollable fluctuations over time (spectral diffusion), creating a serious problem for implementation of the photon-mediated protocols. Here we show that a sequence of optical pulses applied to the solid-state emitter can stabilize the emission line at the desired frequency. We demonstrate efficiency, robustness, and feasibility of the method analytically and numerically. Taking nitrogen-vacancy center in diamond as an example, we show that only several pulses, with the width of 1more » ns, separated by few ns (which is not difficult to achieve) can suppress spectral diffusion. As a result, our method provides a simple and robust way to greatly improve the efficiency of photon-mediated entanglement and/or coupling to photonic cavities for solid-state qubits.« less

  2. Feasibility study of a fission-suppressed tokamak fusion breeder

    SciTech Connect (OSTI)

    Moir, R.W.; Lee, J.D.; Neef, W.S.; Berwald, D.H.; Garner, J.K.; Whitley, R.H.; Ghoniem, N.; Wong, C.P.C.; Maya, I.; Schultz, K.R.

    1984-12-01

    The preliminary conceptual design of a tokamak fissile fuel producer is described. The blanket technology is based on the fission suppressed breeding concept where neutron multiplication occurs in a bed of 2 cm diameter beryllium pebbles which are cooled by helium at 50 atmospheres pressure. Uranium-233 is bred in thorium metal fuel elements which are in the form of snap rings attached to each beryllium pebble. Tritium is bred in lithium bearing material contained in tubes immersed in the pebble bed and is recovered by a purge flow of helium. The neutron wall load is 3 MW/m/sup 2/ and the blanket material is ferritic steel. The net fissile breeding ratio is 0.54 +- 30% per fusion reaction. This results in the production of 4900 kg of /sup 233/U per year from 3000 MW of fusion power. This quantity of fuel will provide makeup fuel for about 12 LWRs of equal thermal power or about 18 1 GW/sub e/ LWRs. The calculated cost of the produced uranium-233 is between $23/g and $53/g or equivalent to $10/kg to $90/kg of U/sub 3/O/sub 8/ depending on government financing or utility financing assumptions. Additional topics discussed in the report include the tokamak operating mode (both steady state and long pulse considered), the design and breeding implications of using a poloidal divertor for impurity control, reactor safety, the choice of a tritium breeder, and fuel management.

  3. Active Suppression of Drilling System Vibrations For Deep Drilling

    SciTech Connect (OSTI)

    Raymond, David W.; Blankenship, Douglas A.; Buerger, Stephen; Mesh, Mikhail; Radigan, William Thomas; Su, Jiann-Cherng

    2015-10-01

    The dynamic stability of deep drillstrings is challenged by an inability to impart controllability with ever-changing conditions introduced by geology, depth, structural dynamic properties and operating conditions. A multi-organizational LDRD project team at Sandia National Laboratories successfully demonstrated advanced technologies for mitigating drillstring vibrations to improve the reliability of drilling systems used for construction of deep, high-value wells. Using computational modeling and dynamic substructuring techniques, the benefit of controllable actuators at discrete locations in the drillstring is determined. Prototype downhole tools were developed and evaluated in laboratory test fixtures simulating the structural dynamic response of a deep drillstring. A laboratory-based drilling applicability demonstration was conducted to demonstrate the benefit available from deployment of an autonomous, downhole tool with self-actuation capabilities in response to the dynamic response of the host drillstring. A concept is presented for a prototype drilling tool based upon the technical advances. The technology described herein is the subject of U.S. Patent Application No. 62219481, entitled "DRILLING SYSTEM VIBRATION SUPPRESSION SYSTEMS AND METHODS", filed September 16, 2015.

  4. Suppression of phosphate liberation from eutrophic lake sediment by using fly ash and ordinary Portland cement

    SciTech Connect (OSTI)

    Heng-Peng Ye; Fan-Zhong Chen; Yan-Qing Sheng; Guo-Ying Sheng; Jia-Mo Fu

    2006-08-15

    In this study, the effect of suppression on phosphate liberation from eutrophic lake sediment by using fly ash and ordinary Portland cement (OPC) was investigated by small scale experiment. A system including sediment, lake water, and several kinds of capping materials was designed to clarify the suppression of phosphate liberation from sediment under the anaerobic condition. The suppression efficiencies of fly ash, OPC and glass bead used as control material were also determined, and these effects were discussed. The suppression efficiency of glass bead was 44.4%, and those of fly ash and OPC were 84.4%, 94.9%, respectively. The suppression by fly ash and OPC was mainly carried out by the adsorption effect, in addition to the covering effect. The suppression efficiency depended on the amounts of the material used, and about 90% of liberated phosphate was suppressed by fly ash of 10.0 Kg m{sup -2}, and OPC of 6.0 Kg m{sup -2}. The concentrations of heavy metals, such as mercury, cadmium, lead, copper, zinc, chromium, silver, arsenic and nickel, in fly ash and OPC were lower than those in the environmental materials. And it was considered that the concentrations of heavy metals in fly ash and OPC were too low to influence the ecosystem in natural water region.

  5. Initial conditions dependency in heavy-quarks suppression in ultra-relativistic collisions

    SciTech Connect (OSTI)

    Alves Garcia Prado, Caio; Alarcon do Passo Suaide, Alexandre

    2013-05-06

    Heavy quark suppression in central Au+Au collisions is expected to be smaller than that of light quarks. However experimental data suggest that they are evenly suppressed. We propose considering fluctuations in the medium as they may lead to high-density regions which in turn can cause a considerable quark suppression at the early stages of the collision evolution. To analyse the overall effect of these fluctuations we perform computer simulations of charm and bottom propagating through the quark-gluon plasma and obtain estimates of the nuclear modification factor R{sub AA}. This quantity gives us information about the heavy quark suppression that can be compared to published experimental data from the STAR experiment.

  6. Fission-suppressed fusion breeder on the thorium cycle and nonprolifer...

    Office of Scientific and Technical Information (OSTI)

    Each fusion reaction can produce typically 0.6 fissile atoms and release about 1.6 times the 14 MeV neutron's energy in the blanket in the fission-suppressed design. This ...

  7. Experiments in sideband suppression on the Los Alamos National Laboratory Free-Electron Laser

    SciTech Connect (OSTI)

    White, C.J.; Coyle, M.R.; Paxton, A.H. (Mission Research Corp., Albuquerque, NM (United States). Laser and Optical R and D Group); O'Shea, P.G.; Bender, S.C.; Byrd, D.A.; Feldman, D.W.; Goldstein, J.C.: Pitcher, E.J.; Zaugg, T.J. (Los Alamos National Lab., NM (United States))

    1993-01-01

    Two versions of the Phase-Step Mirror'' (PSM), a novel optical component that prevents the formation of sidebands in a Free-Electron Laser (FEL) were tested on the Los Alamos National Laboratory (LANL) APEX FEL. Sideband suppression and frequency control with high extraction efficiency and single line, transform limited operation were demonstrated. The results of our LANL experiments and computer simulations showed that for very high gain applications, the first-order sideband is completely suppressed, but the laser gain is so strong that on about pass 300 the sideband at the second-order or next free spectral range of the PSM appears. This second-order sideband may be suppressed by designing a PSM with grooves having two alternating depths, one chosen to suppress the first-order sideband, and the other, the second-order sideband.

  8. Experiments in sideband suppression on the Los Alamos National Laboratory Free-Electron Laser

    SciTech Connect (OSTI)

    White, C.J.; Coyle, M.R.; Paxton, A.H. [Mission Research Corp., Albuquerque, NM (United States). Laser and Optical R and D Group; O`Shea, P.G.; Bender, S.C.; Byrd, D.A.; Feldman, D.W.; Goldstein, J.C.: Pitcher, E.J.; Zaugg, T.J. [Los Alamos National Lab., NM (United States)

    1993-06-01

    Two versions of the ``Phase-Step Mirror`` (PSM), a novel optical component that prevents the formation of sidebands in a Free-Electron Laser (FEL) were tested on the Los Alamos National Laboratory (LANL) APEX FEL. Sideband suppression and frequency control with high extraction efficiency and single line, transform limited operation were demonstrated. The results of our LANL experiments and computer simulations showed that for very high gain applications, the first-order sideband is completely suppressed, but the laser gain is so strong that on about pass 300 the sideband at the second-order or next free spectral range of the PSM appears. This second-order sideband may be suppressed by designing a PSM with grooves having two alternating depths, one chosen to suppress the first-order sideband, and the other, the second-order sideband.

  9. Suppression of x-rays generated by runaway electrons in ATF

    SciTech Connect (OSTI)

    Rasmussen, D.A.; England, A.C.; Eberle, C.C.; Devan, W.R.; Harris, J.H.; Jernigan, T.C.; Kindsfather, R.R.; Morris, R.N.; Murakami, M.; Neilson, G.H.

    1987-01-01

    X-ray emission from runaway electrons on ATF is a serious issue. Runaway suppression techniques used on Heliotron-E are not adequate for ATF. Three approaches have been developed to suppress runaway production. Monitoring devices have been installed in occupied areas and personnel access and exposure will be limited. Additional shielding will be added as required. These systems will be ready for installation and testing on ATF prior to commissioning or first plasma operation.

  10. Gain media edge treatment to suppress amplified spontaneous emission in a high power laser

    DOE Patents [OSTI]

    Hackel, Lloyd A.; Soules, Thomas F.; Fochs, Scott N.; Rotter, Mark D.; Letts, Stephan A.

    2008-12-09

    A novel method and apparatus for suppressing ASE and parasitic oscillation modes in a high average power laser is introduced. By roughening one or more peripheral edges of a solid-state crystal or ceramic laser gain media and by bonding such edges using a substantially high index bonding elastomer or epoxy to a predetermined electromagnetic absorbing arranged adjacent to the entire outer surface of the peripheral edges of the roughened laser gain media, ASE and parasitic oscillation modes can be effectively suppressed.

  11. Gain media edge treatment to suppress amplified spontaneous emission in a high power laser

    DOE Patents [OSTI]

    Hackel, Lloyd A.; Soules, Thomas F.; Fochs, Scott N.; Rotter, Mark D.; Letts, Stephan A.

    2011-02-22

    A novel method and apparatus for suppressing ASE and/or parasitic oscillation modes in a laser is introduced. By roughening one or more peripheral edges of a solid-state crystal or ceramic laser gain media and by bonding such edges to a predetermined electromagnetic absorbing material arranged adjacent to the entire outer surface of the peripheral edges of the roughened laser gain media, ASE, parasitic oscillation modes and/or residual pump energy can be effectively suppressed.

  12. Apocynin suppresses the progression of atherosclerosis in apoE-deficient mice by inactivation of macrophages

    SciTech Connect (OSTI)

    Kinoshita, Hiroyuki; Matsumura, Takeshi; Ishii, Norio; Fukuda, Kazuki; Senokuchi, Takafumi; Motoshima, Hiroyuki; Kondo, Tatsuya; Taketa, Kayo; Kawasaki, Shuji; Hanatani, Satoko; Takeya, Motohiro; Nishikawa, Takeshi; Araki, Eiichi

    2013-02-08

    Highlights: ► We examined the anti-athrogenic effect of apocynin in atherosclerotic model mice. ► Apocynin prevented atherosclerotic lesion formation. ► Apocynin suppressed ROS production in aorta and in macrophages. ► Apocynin suppressed cytokine expression and cell proliferation in macrophages. ► Apocynin may be beneficial compound for the prevention of atherosclerosis. -- Abstract: Production of reactive oxygen species (ROS) and other proinflammatory substances by macrophages plays an important role in atherogenesis. Apocynin (4-hydroxy-3-methoxy-acetophenone), which is well known as a NADPH oxidase inhibitor, has anti-inflammatory effects including suppression of the generation of ROS. However, the suppressive effects of apocynin on the progression of atherosclerosis are not clearly understood. Thus, we investigated anti-atherosclerotic effects of apocynin using apolipoprotein E-deficient (apoE{sup –/–}) mice in vivo and in mouse peritoneal macrophages in vitro. In atherosclerosis-prone apoE{sup –/–} mice, apocynin suppressed the progression of atherosclerosis, decreased 4-hydroxynonenal-positive area in atherosclerotic lesions, and mRNA expression of monocyte chemoattractant protein-1 (MCP-1) and interleukin-6 (IL-6) in aorta. In mouse peritoneal macrophages, apocynin suppressed the Ox-LDL-induced ROS generation, mRNA expression of MCP-1, IL-6 and granulocyte/macrophage colony-stimulating factor, and cell proliferation. Moreover, immunohistochemical studies revealed that apocynin decreased the number of proliferating cell nuclear antigen-positive macrophages in atherosclerotic lesions of apoE{sup –/–} mice. These results suggested that apocynin suppressed the formation of atherosclerotic lesions, at least in part, by inactivation of macrophages. Therefore, apocynin may be a potential therapeutic material to prevent the progression of atherosclerosis.

  13. GNOSIS: THE FIRST INSTRUMENT TO USE FIBER BRAGG GRATINGS FOR OH SUPPRESSION

    SciTech Connect (OSTI)

    Trinh, Christopher Q.; Ellis, Simon C.; Bland-Hawthorn, Joss; Bryant, Julia; O'Byrne, John; Lawrence, Jon S.; Horton, Anthony J.; Shortridge, Keith; Case, Scott; Colless, Matthew; Gers, Luke; Lee, Steve; Miziarski, Stan; Leon-Saval, Sergio G.; Couch, Warrick; Glazebrook, Karl; Freeman, Kenneth; Loehmannsroeben, Hans-Gerd; and others

    2013-02-01

    The near-infrared is an important part of the spectrum in astronomy, especially in cosmology because the light from objects in the early universe is redshifted to these wavelengths. However, deep near-infrared observations are extremely difficult to make from ground-based telescopes due to the bright background from the atmosphere. Nearly all of this background comes from the bright and narrow emission lines of atmospheric hydroxyl (OH) molecules. The atmospheric background cannot be easily removed from data because the brightness fluctuates unpredictably on short timescales. The sensitivity of ground-based optical astronomy far exceeds that of near-infrared astronomy because of this long-standing problem. GNOSIS is a prototype astrophotonic instrument that utilizes 'OH suppression fibers' consisting of fiber Bragg gratings and photonic lanterns to suppress the 103 brightest atmospheric emission doublets between 1.47 and 1.7 {mu}m. GNOSIS was commissioned at the 3.9 m Anglo-Australian Telescope with the IRIS2 spectrograph to demonstrate the potential of OH suppression fibers, but may be potentially used with any telescope and spectrograph combination. Unlike previous atmospheric suppression techniques GNOSIS suppresses the lines before dispersion and in a manner that depends purely on wavelength. We present the instrument design and report the results of laboratory and on-sky tests from commissioning. While these tests demonstrated high throughput ( Almost-Equal-To 60%) and excellent suppression of the skylines by the OH suppression fibers, surprisingly GNOSIS produced no significant reduction in the interline background and the sensitivity of GNOSIS+IRIS2 is about the same as IRIS2. It is unclear whether the lack of reduction in the interline background is due to physical sources or systematic errors as the observations are detector noise dominated. OH suppression fibers could potentially impact ground-based astronomy at the level of adaptive optics or greater

  14. Tracking multiple generation and suppression of secondary electrons on periodic triangular surface

    SciTech Connect (OSTI)

    Li, S.; Wang, J. G.; Zhu, M.; Peng, J. C.; Xie, J. L.; Wu, X. L.; Guo, L. T.; Chang, C.; Xiong, Z. F.; Department of Engineering Physics, Tsinghua University, Beijing 10084

    2013-12-15

    To research the dynamic course of multipactor suppression on the periodically patterned surface, tens of electron collision processes are tracked by numerical calculation. The influences of microwave frequency, amplitude of RF electric field, slope angle, the local field enhancement, and the tilted incident electric field on the multipactor suppression are studied by tracking multi-generation electrons' trajectories, hopping and flight time, collision energy, and secondary emission yield. Meanwhile, the dynamic processes of secondary electrons on the periodic surface are analyzed by particle-in-cell (PIC) simulation. The PIC results are consistent with the analytical results in which the electrons fly reciprocatingly between the slopes and impact on the slopes; the methods of increasing the slope angle, enlarging the RF field, and lowering the frequency in a certain range are helpful to enhance the multipactor suppression steadily and persistently.

  15. Observation of Wakefield Suppression in a Photonic-Band-Gap Accelerator Structure

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

    Simakov, Evgenya I.; Arsenyev, Sergey A.; Buechler, Cynthia E.; Edwards, Randall L.; Romero, William P.; Conde, Manoel; Ha, Gwanghui; Power, John G.; Wisniewski, Eric E.; Jing, Chunguang

    2016-02-10

    We report experimental observation of higher order mode (HOM) wakefield suppression in a room-temperature traveling-wave photonic band gap (PBG) accelerating structure at 11.700 GHz. It has been long recognized that PBG structures have potential for reducing long-range wakefields in accelerators. The first ever demonstration of acceleration in a room-temperature PBG structure was conducted in 2005. Since then, the importance of PBG accelerator research has been recognized by many institutions. However, the full experimental characterization of the wakefield spectrum and demonstration of wakefield suppression when the accelerating structure is excited by an electron beam has not been performed to date. Wemore » conducted an experiment at the Argonne Wakefield Accelerator (AWA) test facility and observed wakefields excited by a single high charge electron bunch when it passes through a PBG accelerator structure. Lastly, excellent HOM suppression properties of the PBG accelerator were demonstrated in the beam test.« less

  16. The suppression effect of external magnetic field on the high-power microwave window multipactor phenomenon

    SciTech Connect (OSTI)

    Zhang, Xue Wang, Yong; Fan, Junjie

    2015-02-15

    To suppress the surface multipactor phenomenon and improve the transmitting power of the high-power microwave window, the application of external magnetic fields is theoretically analyzed and simulated. A Monte Carlo algorithm is used to track the secondary electron trajectories and study the multipactor scenario on the surface of a cylinder window. It is confirmed that over-resonant magnetic fields (an external magnetic field whose magnitude is slightly greater than that of a resonant magnetic field) will generate a compensating trajectory and collision, which can suppress the secondary electron avalanche. The optimal value of this external magnetic field that will avoid the multipactor phenomenon on cylinder windows is discussed.

  17. A method for pressure-pulse suppression in fluid-filled piping

    SciTech Connect (OSTI)

    Shin, Y.W.; Bielick, E.F. ); Wiedermann, A.H. ); Ockert, C.E. )

    1990-01-01

    A simple, nondestructive method to suppress pressure pulses in fluid-filled piping was proposed and theoretically analyzed earlier. In this paper, the proposed method is verified experimentally. The results of experiments performed for the range of parameters of practical importance indicated that the attenuation of pressure pulses was in accordance with the theoretical predictions. This paper describes the experimental setup and the test models of the proposed pulse suppression devices and discusses the experimental results. In particular, the measured attenuation factors are presented and compared with the theoretical predictions. 8 refs., 17 figs., 2 tabs.

  18. A method for pressure-pulse suppression in fluid-filled piping

    SciTech Connect (OSTI)

    Shin, Y.W.; Bielick, E.F. ); Wiedermann, A.H. ); Ockert, C.E. )

    1989-01-01

    A simple, nondestructive method to suppress pressure pulses in fluid-filled piping was proposed and theoretically analyzed earlier. In this paper, the proposed method is verified experimentally. The results of experiments performed for the range of parameters of practical importance indicated that the attenuation of pressure pulses was in accordance with the theoretical predictions. This paper describes the experimental setup and the test models of the proposed pulse suppression devices and discusses the experimental results. In particular, the measured attenuation factors are presented and compared with the theoretical predictions. 8 ref., 17 fig., 2 tab.

  19. Suppression of n=1 Tilt Instability by Magnetic Shaping Coils in Rotamak Plasmas

    SciTech Connect (OSTI)

    Yang, X.; Petrov, Y.; Huang, T. S.

    2009-06-26

    Measurements from the array of Mirnov magnetic coils provide the first evidence for n=1 tilt and radial shift instabilities in a 40 ms field-reversed configuration (FRC) driven by rotating magnetic field. External plasma-shaping magnetic coils are utilized to suppress the n=1 instability modes. It is demonstrated that by energizing the middle shaping coil with 250-500 A current, the tilt mode is completely suppressed when a doublet FRC with an internal figure-of-eight separatrix is formed.

  20. METHOD OF SUPPRESSING UAl$sub 4$ FORMATION IN U-Al ALLOYS

    DOE Patents [OSTI]

    Picklesimer, M.L.; Thurber, W.C.

    1960-08-23

    A method is given for suppressing the formation of UAl/sub 4/ in uranium- - aluminum alloys, thereby rendering these alloys more easily workable. The method comprises incorporating in the base alloy a Group Four element selected from the group consisting of Si, Ti, Ge, Zr, and Sn, the addition preferably being within the range of 0.5to20at.%.

  1. The Use of Oil Refinery Wastes as a Dust Suppression Surfactant for Use in Mining

    SciTech Connect (OSTI)

    Dixon-Hardy, D.W.; Beyhan, S.; Ediz, I.G.; Erarslan, K.

    2008-10-15

    In this research, the suitability of a selection of petroleum refinery wastes as a dust suppressant were examined. Dust is a significant problem in surface and underground mining mainly because of its adverse effects on human health and machinery. Hence, dust control and suppression is a vital part of mine planning for mining engineers. Water is the oldest and the cheapest suppressant in dealing with the mine dusts. However, surfactant use has recently been used for a wider range of applications in the mining industry. In order to carry out laboratory experiments, a dust chamber was designed and manufactured. The chamber has an inlet for coal dust entrance and a nozzle for spraying water and the oil refinery wastes. Water and the surfactants were mixed at various ratios and then sprayed onto the coal dusts within the cell. Dust concentration was measured systematically to determine the effects of surfactant containing solution on the coal dust and the data obtained by the measurements were analyzed. The results showed that the oil refinery wastes could be used as a dust suppressant, which may create an economical utilization for the wastes concerned.

  2. Isoniazid suppresses antioxidant response element activities and impairs adipogenesis in mouse and human preadipocytes

    SciTech Connect (OSTI)

    Chen, Yanyan; Xue, Peng; Hou, Yongyong; Zhang, Hao; Zheng, Hongzhi; Zhou, Tong; Qu, Weidong; Teng, Weiping; Zhang, Qiang; Andersen, Melvin E.; Pi, Jingbo

    2013-12-15

    Transcriptional signaling through the antioxidant response element (ARE), orchestrated by the Nuclear factor E2-related factor 2 (Nrf2), is a major cellular defense mechanism against oxidative or electrophilic stress. Here, we reported that isoniazid (INH), a widely used antitubercular drug, displays a substantial inhibitory property against ARE activities in diverse mouse and human cells. In 3T3-L1 preadipocytes, INH concentration-dependently suppressed the ARE-luciferase reporter activity and mRNA expression of various ARE-dependent antioxidant genes under basal and oxidative stressed conditions. In keeping with our previous findings that Nrf2-ARE plays a critical role in adipogenesis by regulating expression of CCAAT/enhancer-binding protein ? (C/EBP?) and peroxisome proliferator-activated receptor ? (PPAR?), suppression of ARE signaling by INH hampered adipogenic differentiation of 3T3-L1 cells and human adipose-derived stem cells (ADSCs). Following adipogenesis induced by hormonal cocktails, INH-treated 3T3-L1 cells and ADSCs displayed significantly reduced levels of lipid accumulation and attenuated expression of C/EBP? and PPAR?. Time-course studies in 3T3-L1 cells revealed that inhibition of adipogenesis by INH occurred in the early stage of terminal adipogenic differentiation, where reduced expression of C/EBP? and C/EBP? was observed. To our knowledge, the present study is the first to demonstrate that INH suppresses ARE signaling and interrupts with the transcriptional network of adipogenesis, leading to impaired adipogenic differentiation. The inhibition of ARE signaling may be a potential underlying mechanism by which INH attenuates cellular antioxidant response contributing to various complications. - Highlights: Isoniazid suppresses ARE-mediated transcriptional activity. Isoniazid inhibits adipogenesis in preadipocytes. Isoniazid suppresses adipogenic gene expression during adipogenesis.

  3. Experiments of ECCS strainer blockage and debris settling in suppression pools

    SciTech Connect (OSTI)

    Hecker, G.E.; Johnson, A.B.; Murthy, P.; Padmanabhan

    1996-03-01

    If a rupture occurs in a nuclear power station pipe that leads to or from the reactor pressure vessel, the resultant Loss of Coolant Accident (LOCA) would initiate a chain of events involving complex flow phenomena. In a Boiling Water Reactor (BWR), the steam or liquid pipe break pressurizes the dry well, forcing the inert containment gases and steam through downcomers into the suppression pool, thoroughly mixing any particulates and pipe insulation debris carried with the gas flow to the pool. As the steam flow decreases, its unsteady condensation at the end of the downcomers (Condensation Oscillation and Chugging) produces continued water motion in the suppression pool and downcomers. During the blowdown event, high pressure and then low pressure pumps automatically start injecting water from the suppression pool into the reactor to keep its temperature under control. Proper functioning of this Emergency Core Cooling System (ECCS) is critical for the first 30 minutes or so, before operators have time to consider and align alternative sources of cooling water. A major concern for proper operation of the ECCS is the effect of fragmented insulation and plant particulates on the head loss at pump suction strainers. Sufficient loss could exceed the NPSH margin, causing cavitation with a resultant loss of pump capacity and longevity. The bead loss increases with the mass of debris accumulated on the pump strainers, which in turn is dependent on the debris concentration versus time in the suppression pool. This paper describes two sets of experiments that quantified the strainer head loss. One set of experiments considered the mixing and settling of fibrous insulation debris and fine iron oxide particles in the suppression pool during and after chugging. These tests used a reduced scale facility which duplicated the kinetic energy per unit water volume to define the concentration of the actual materials in the pool versus time.

  4. An assessment of alternatives and technologies for replacing ozone- depleting substances at DOE facilities

    SciTech Connect (OSTI)

    Purcell, C.W.; Miller, K.B.; Friedman, J.R.; Rapoport, R.D.; Conover, D.R.; Hendrickson, P.L. ); Koss, T.C. . Office of Environmental Guidance)

    1992-10-01

    Title VI of the Clean Air Act, as amended, mandates a production phase-out for ozone-depleting substances (ODSs). These requirements will have a significant impact on US Department of Energy (DOE) facilities. Currently, DOE uses ODSs in three major activities: fire suppression (halon), refrigeration and cooling (chlorofluorocarbons [CFCs]), and cleaning that requires solvents (CFCs, methyl chloroform, and carbon tetrachloride). This report provides basic information on methods and strategies to phase out use of ODSs at DOE facilities.

  5. Low concentrations of bisphenol a suppress thyroid hormone receptor transcription through a nongenomic mechanism

    SciTech Connect (OSTI)

    Sheng, Zhi-Guo; Tang, Yuan; Liu, Yu-Xiang; Yuan, Ye; Zhao, Bao-Quan; Chao, Xi-Juan; Zhu, Ben-Zhan

    2012-02-15

    Bisphenol (BPA) is one of the highest-volume chemicals produced worldwide, and human exposure to BPA is thought to be ubiquitous. Various rodent and in vitro studies have shown that thyroid hormone (TH) function can be impaired by BPA. However, it is still unknown if low concentrations of BPA can suppress the thyroid hormone receptor (TR) transcription. The present study aims to investigate the possible suppressing effects of low concentrations of BPA on TR transcription and the involved mechanism(s) in CV-1 cells derived from cercopithecus aethiops monkey kidneys. Using gene reporter assays, BPA at concentrations as low as 10{sup ?9} M suppresses TR or steroid receptor coactivator-1(SRC-1)-enhanced TR transcription, but not reducing TR/SRC-1 interaction in mammalian two-hybrid and glutathione S-transferase pull-down studies. It has been further shown that both nuclear receptor co-repressor (N-CoR) and silencing mediator for retinoid and thyroid hormone receptors (SMRT) are recruited to the TR-?1 by BPA in the presence of physiologic concentrations of T3 or T4. However, the overexpression of ?3 integrin or c-Src significantly reduces BPA-induced recruitment of N-CoR/SMRT to TR or suppression of TR transcription. Furthermore, BPA inhibits the T3/T4-mediated interassociation of the ?3 integrin/c-Src/MAPK/TR-?1 pathways by the co-immunoprecipitation. These results indicate that low concentrations of BPA suppress the TR transcription by disrupting physiologic concentrations of T3/T4-mediated ?3 integrin/c-Src/MAPK/TR-?1 pathways, followed by recruiting N-CoR/SMRT to TR-?1, providing a novel insight regarding the TH disruption effects of low concentration BPA. -- Highlights: ? Environmentally relevant concentrations of BPA suppress TR transcription. ? BPA recruits the N-CoR/SMRT to TR under the physiologic concentrations of T3/T4. ? BPA disrupts T3/T4-mediated ?3 integrin/c-Src/MAPK/TR-?1 pathways.

  6. SURFACE FILMS TO SUPPRESS FIELD EMISSION IN HIGH-POWER MICROWAVE COMPONENTS

    SciTech Connect (OSTI)

    Hirshfield, Jay l

    2014-02-07

    Results are reported on attempts to reduce the RF breakdown probability on copper accelerator structures by applying thin surface films that could suppress field emission of electrons. Techniques for application and testing of copper samples with films of metals with work functions higher than copper are described, principally for application of platinum films, since platinum has the second highest work function of any metal. Techniques for application of insulating films are also described, since these can suppress field emission and damage on account of dielectric shielding of fields at the copper surface, and on account of the greater hardness of insulating films, as compared with copper. In particular, application of zirconium oxide films on high-field portions of a 11.424 GHz SLAC cavity structure for breakdown tests are described.

  7. System and method that suppresses intensity fluctuations for free space high-speed optical communication

    DOE Patents [OSTI]

    Berman, Gennady P.; Bishop, Alan R.; Nguyen, Dinh C.; Chernobrod, Boris M.; Gorshkov, Vacheslav N.

    2009-10-13

    A high-speed (Gbps), free space optical communication system is based on spectral encoding of radiation from a wide band light source, such as a laser. By using partially coherent laser beams in combination with a relatively slow photosensor, scintillations can be suppressed by orders of magnitude for distances of more than 10 km. To suppress the intensity fluctuations due to atmospheric turbulence, a source with partial transverse coherence in combination with slow response time photodetector is used. Information is encoded in the spectral domain of a wideband optical source by modulation of spectral amplitudes. A non-coherent light source with wide spectrum (an LED, for example) may be used for high-speed communication over short (less than about a mile) distances.

  8. NO.sub.x catalyst and method of suppressing sulfate formation in an exhaust purification system

    DOE Patents [OSTI]

    Balmer-Millar, Mari Lou; Park, Paul W.; Panov, Alexander G.

    2006-08-22

    The activity and durability of a zeolite lean-bum NOx catalyst can be increased by loading metal cations on the outer surface of the zeolite. However, the metal loadings can also oxidize sulfur dioxide to cause sulfate formation in the exhaust. The present invention is a method of suppressing sulfate formation in an exhaust purification system including a NO.sub.x catalyst. The NO.sub.x catalyst includes a zeolite loaded with at least one metal. The metal is selected from among an alkali metal, an alkaline earth metal, a lanthanide metal, a noble metal, and a transition metal. In order to suppress sulfate formation, at least a portion of the loaded metal is complexed with at least one of sulfate, phosphate, and carbonate.

  9. NO.sub.x catalyst and method of suppressing sulfate formation in an exhaust purification system

    DOE Patents [OSTI]

    Balmer-Millar, Mari Lou; Park, Paul W.; Panov, Alexander G.

    2007-06-26

    The activity and durability of a zeolite lean-burn NOx catalyst can be increased by loading metal cations on the outer surface of the zeolite. However, the metal loadings can also oxidize sulfur dioxide to cause sulfate formation in the exhaust. The present invention is a method of suppressing sulfate formation in an exhaust purification system including a NO.sub.x catalyst. The NO.sub.x catalyst includes a zeolite loaded with at least one metal. The metal is selected from among an alkali metal, an alkaline earth metal, a lanthanide metal, a noble metal, and a transition metal. In order to suppress sulfate formation, at least a portion of the loaded metal is complexed with at least one of sulfate, phosphate, and carbonate.

  10. An ion guide laser ion source for isobar-suppressed rare isotope beams

    SciTech Connect (OSTI)

    Raeder, Sebastian Ames, Friedhelm; Bishop, Daryl; Bricault, Pierre; Kunz, Peter; Mjs, Anders; Heggen, Henning; Institute of Applied Physics, TU Darmstadt, Schlossgartenstr. 7, 64289 Darmstadt ; Lassen, Jens Teigelhfer, Andrea; Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2

    2014-03-15

    Modern experiments at isotope separator on-line (ISOL) facilities like ISAC at TRIUMF often depend critically on the purity of the delivered rare isotope beams. Therefore, highly selective ion sources are essential. This article presents the development and successful on-line operation of an ion guide laser ion source (IG-LIS) for the production of ion beams free of isobaric contamination. Thermionic ions from the hot ISOL target are suppressed by an electrostatic potential barrier, while neutral radio nuclides effusing out are resonantly ionized by laser radiation within a quadrupole ion guide behind this barrier. The IG-LIS was developed through detailed thermal and ion optics simulation studies and off-line tests with stable isotopes. In a first on-line run with a SiC target a suppression of surface-ionized Na contaminants in the ion beam of up to six orders of magnitude was demonstrated.

  11. Protein A suppresses immune responses during Staphylococcus aureus bloodstream infection in guinea pigs

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

    Kim, Hwan Keun; Falugi, Fabiana; Thomer, Lena; Missiakas, Dominique M.; Schneewind, Olaf

    2015-01-06

    Staphylococcus aureus infection is not associated with the development of protective immunity, and disease relapses occur frequently. We hypothesize that protein A, a factor that binds immunoglobulin Fcγ and cross-links VH3 clan B cell receptors (IgM), is the staphylococcal determinant for host immune suppression. To test this, vertebrate IgM was examined for protein A cross-linking. High VH3 binding activity occurred with human and guinea immunoglobulin, whereas mouse and rabbit immunoglobulins displayed little and no binding, respectively. Establishing a guinea pig model of S. aureus bloodstream infection, we show that protein A functions as a virulence determinant and suppresses host Bmore » cell responses. Immunization with SpAKKAA, which cannot bind immunoglobulin, elicits neutralizing antibodies that enable guinea pigs to develop protective immunity.« less

  12. Suppression criteria of parasitic mode oscillations in a gyrotron beam tunnel

    SciTech Connect (OSTI)

    Kumar, Nitin; Singh, Udaybir; Sinha, A. K.; Singh, T. P.

    2011-02-15

    This paper presents the design criteria of the parasitic mode oscillations suppression for a periodic, ceramic, and copper loaded gyrotron beam tunnel. In such a type of beam tunnel, the suppression of parasitic mode oscillations is an important design problem. A method of beam-wave coupling coefficient and its mathematical formulation are presented. The developed design criteria are used in the beam tunnel design of a 42 GHz gyrotron to be developed for the Indian TOKAMAK system. The role of the thickness and the radius of the beam tunnel copper rings to obtain the developed design criteria are also discussed. The commercially available electromagnetic code CST and the electron trajectory code EGUN are used for the simulations.

  13. Alternative approach for fire suppression of class A, B and C fires in gloveboxes

    SciTech Connect (OSTI)

    Rosenberger, Mark S; Tsiagkouris, James A

    2011-02-10

    Department of Energy (DOE) Orders and National Fire Protection Association (NFPA) Codes and Standards require fire suppression in gloveboxes. Several potential solutions have been and are currently being considered at Los Alamos National Laboratory (LANL). The objective is to provide reliable, minimally invasive, and seismically robust fire suppression capable of extinguishing Class A, B, and C fires; achieve compliance with DOE and NFPA requirements; and provide value-added improvements to fire safety in gloveboxes. This report provides a brief summary of current approaches and also documents the successful fire tests conducted to prove that one approach, specifically Fire Foe{trademark} tubes, is capable of achieving the requirement to provide reliable fire protection in gloveboxes in a cost-effective manner.

  14. Schisantherin A suppresses osteoclast formation and wear particle-induced osteolysis via modulating RANKL signaling pathways

    SciTech Connect (OSTI)

    He, Yi; Zhang, Qing; Shen, Yi; Chen, Xia; Zhou, Feng; Peng, Dan

    2014-07-04

    Highlights: • Schisantherin A suppresses osteoclasts formation and function in vitro. • Schisantherin A impairs RANKL signaling pathway. • Schisantherin A suppresses osteolysis in vivo. • Schisantherin A may be used for treating osteoclast related diseases. - Abstract: Receptor activator of NF-κB ligand (RANKL) plays critical role in osteoclastogenesis. Targeting RANKL signaling pathways has been a promising strategy for treating osteoclast related bone diseases such as osteoporosis and aseptic prosthetic loosening. Schisantherin A (SA), a dibenzocyclooctadiene lignan isolated from the fruit of Schisandra sphenanthera, has been used as an antitussive, tonic, and sedative agent, but its effect on osteoclasts has been hitherto unknown. In the present study, SA was found to inhibit RANKL-induced osteoclast formation and bone resorption. The osteoclastic specific marker genes induced by RANKL including c-Src, SA inhibited OSCAR, cathepsin K and TRAP in a dose dependent manner. Further signal transduction studies revealed that SA down-regulate RANKL-induced nuclear factor-kappaB (NF-κB) signaling activation by suppressing the phosphorylation and degradation of IκBα, and subsequently preventing the NF-κB transcriptional activity. Moreover, SA also decreased the RANKL-induced MAPKs signaling pathway, including JNK and ERK1/2 posphorylation while had no obvious effects on p38 activation. Finally, SA suppressed the NF-κB and MAPKs subsequent gene expression of NFATc1 and c-Fos. In vivo studies, SA inhibited osteoclast function and exhibited bone protection effect in wear-particle-induced bone erosion model. Taken together, SA could attenuate osteoclast formation and wear particle-induced osteolysis by mediating RANKL signaling pathways. These data indicated that SA is a promising therapeutic natural compound for the treatment of osteoclast-related prosthesis loosening.

  15. The effect of periodic wavy profile on suppressing window multipactor under arbitrary electromagnetic mode

    SciTech Connect (OSTI)

    Chang, C.; Liu, Y. S.; Chen, C. H.; Guo, L. T.; Li, S.; Wu, X. L.; Verboncoeur, J.

    2015-01-05

    The three-dimensional periodic ripple profile with each unit of rotational symmetric surface is proposed to suppress multipactor for arbitrary electromagnetic mode with any polarization. The field distribution and multipactor electron dynamics on the wavy surface are studied to illustrate the multipactor inhibition mechanism. High power microwave experiment was conducted to demonstrate the effect of wavy surface on significantly improving the window power capacity.

  16. Observation of Shot Noise Suppression at Optical Wavelengths in a Relativistic Electron Beam

    SciTech Connect (OSTI)

    Ratner, Daniel; Stupakov, Gennady; /SLAC

    2012-06-19

    Control of collective properties of relativistic particles is increasingly important in modern accelerators. In particular, shot noise affects accelerator performance by driving instabilities or by competing with coherent processes. We present experimental observations of shot noise suppression in a relativistic beam at the Linac Coherent Light Source. By adjusting the dispersive strength of a chicane, we observe a decrease in the optical transition radiation emitted from a downstream foil. We show agreement between the experimental results, theoretical models, and 3D particle simulations.

  17. Instability suppression of clusters of vector-necklace-ring solitons in nonlocal media

    SciTech Connect (OSTI)

    Shen Ming; Kong Qian; Jeng, Chien-Chung; Ge Lijuan; Lee, Ray-Kuang; Krolikowski, Wieslaw

    2011-02-15

    We study the instability suppression of vector-necklace-ring soliton clusters carrying zero, integer, and fractional angular momentums in nonlocal nonlinear media with an arbitrary degree of nonlocality. We show that the combination of nonlocality and mutual trapping of soliton constituent components can completely stabilize the vector-necklace-ring soliton clusters which are otherwise only quasistable in local media. Our results may be useful to studies of the novel soliton states in Bose-Einstein with dipolar long-range interactions.

  18. PPPL extends system for suppressing instabilities to long-pulse experiments

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

    on KSTAR | Princeton Plasma Physics Lab PPPL extends system for suppressing instabilities to long-pulse experiments on KSTAR By John Greenwald March 18, 2014 Tweet Widget Google Plus One Share on Facebook A look into the microwave launcher showing the steering mirrors that guide the beam into the plasma. (Photo by PPPL) A look into the microwave launcher showing the steering mirrors that guide the beam into the plasma. PPPL collaborations have been instrumental in developing a system to

  19. PPPL extends system for suppressing instabilities to long-pulse experiments

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

    on KSTAR | Princeton Plasma Physics Lab PPPL extends system for suppressing instabilities to long-pulse experiments on KSTAR By John Greenwald March 19, 2014 Tweet Widget Google Plus One Share on Facebook A look into the microwave launcher showing the steering mirrors that guide the beam into the plasma. (Photo by PPPL) A look into the microwave launcher showing the steering mirrors that guide the beam into the plasma. PPPL collaborations have been instrumental in developing a system to

  20. MicroRNA-340 suppresses osteosarcoma tumor growth and metastasis by directly targeting ROCK1

    SciTech Connect (OSTI)

    Zhou, Xin; Wei, Min; Wang, Wei

    2013-08-09

    Highlights: •miR-340 is downregulated in OS cell lines and tissues. •miR-340 suppresses OS cell proliferation, migration and invasion. •miR-340 suppresses tumor growth and metastasis of OS cells in nude mice. •ROCK1 is a target gene of miR-340. •ROCK1 is involved in miR-340-induced suppression of OS cell proliferation, migration and invasion. -- Abstract: MicroRNAs (miRNAs) play key roles in cancer development and progression. In the present study, we investigated the role of miR-340 in the progression and metastasis of osteosarcoma (OS). Our results showed that miR-340 was frequently downregulated in OS tumors and cell lines. Overexpression of miR-340 in OS cell lines significantly inhibited cell proliferation, migration, and invasion in vitro, and tumor growth and metastasis in a xenograft mouse model. ROCK1 was identified as a target of miR-340, and ectopic expression of miR-340 downregulated ROCK1 by direct binding to its 3′ untranslated region. siRNA-mediated silencing of ROCK1 phenocopied the effects of miR-340 overexpression, whereas restoration of ROCK1 in miR-340-overexpressing OS cells reversed the suppressive effects of miR-340. Together, these findings indicate that miR-340 acts as a tumor suppressor and its downregulation in tumor tissues may contribute to the progression and metastasis of OS through a mechanism involving ROCK1, suggesting miR-340 as a potential new diagnostic and therapeutic target for the treatment of OS.

  1. Impaired methylation as a novel mechanism for proteasome suppression in liver cells

    SciTech Connect (OSTI)

    Osna, Natalia A.; White, Ronda L.; Donohue, Terrence M.; Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68105 ; Beard, Michael R.; Tuma, Dean J.; Kharbanda, Kusum K.; Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE 68105

    2010-01-08

    The proteasome is a multi-catalytic protein degradation enzyme that is regulated by ethanol-induced oxidative stress; such suppression is attributed to CYP2E1-generated metabolites. However, under certain conditions, it appears that in addition to oxidative stress, other mechanisms are also involved in proteasome regulation. This study investigated whether impaired protein methylation that occurs during exposure of liver cells to ethanol, may contribute to suppression of proteasome activity. We measured the chymotrypsin-like proteasome activity in Huh7CYP cells, hepatocytes, liver cytosols and nuclear extracts or purified 20S proteasome under conditions that maintain or prevent protein methylation. Reduction of proteasome activity of hepatoma cell and hepatocytes by ethanol or tubercidin was prevented by simultaneous treatment with S-adenosylmethionine (SAM). Moreover, the tubercidin-induced decline in proteasome activity occurred in both nuclear and cytosolic fractions. In vitro exposure of cell cytosolic fractions or highly purified 20S proteasome to low SAM:S-adenosylhomocysteine (SAH) ratios in the buffer also suppressed proteasome function, indicating that one or more methyltransferase(s) may be associated with proteasomal subunits. Immunoblotting a purified 20S rabbit red cell proteasome preparation using methyl lysine-specific antibodies revealed a 25 kDa proteasome subunit that showed positive reactivity with anti-methyl lysine. This reactivity was modified when 20S proteasome was exposed to differential SAM:SAH ratios. We conclude that impaired methylation of proteasome subunits suppressed proteasome activity in liver cells indicating an additional, yet novel mechanism of proteasome activity regulation by ethanol.

  2. Knockdown of p53 suppresses Nanog expression in embryonic stem cells

    SciTech Connect (OSTI)

    Abdelalim, Essam Mohamed; Tooyama, Ikuo

    2014-01-10

    Highlights: We investigate the role of p53 in ESCs in the absence of DNA damage. p53 knockdown suppresses ESC proliferation. p53 knockdown downregulates Nanog expression. p53 is essential for mouse ESC self-renewal. -- Abstract: Mouse embryonic stem cells (ESCs) express high levels of cytoplasmic p53. Exposure of mouse ESCs to DNA damage leads to activation of p53, inducing Nanog suppression. In contrast to earlier studies, we recently reported that chemical inhibition of p53 suppresses ESC proliferation. Here, we confirm that p53 signaling is involved in the maintenance of mouse ESC self-renewal. RNA interference-mediated knockdown of p53 induced downregulation of p21 and defects in ESC proliferation. Furthermore, p53 knockdown resulted in a significant downregulation in Nanog expression at 24 and 48 h post-transfection. p53 knockdown also caused a reduction in Oct4 expression at 48 h post-transfection. Conversely, exposure of ESCs to DNA damage caused a higher reduction of Nanog expression in control siRNA-treated cells than in p53 siRNA-treated cells. These data show that in the absence of DNA damage, p53 is required for the maintenance of mouse ESC self-renewal by regulating Nanog expression.

  3. Geant4 Model Validation of Compton Suppressed System for Process monitoring of Spent Fuel

    SciTech Connect (OSTI)

    Bender, Sarah; Unlu, Kenan; Orton, Christopher R.; Schwantes, Jon M.

    2013-05-01

    Nuclear material accountancy is of continuous concern for the regulatory, safeguards, and verification communities. In particular, spent nuclear fuel reprocessing facilities pose one of the most difficult accountancy challenges: monitoring highly radioactive, fluid sample streams in near real-time. The Multi-Isotope Process monitor will allow for near-real-time indication of process alterations using passive gamma-ray detection coupled with multivariate analysis techniques to guard against potential material diversion or to enhance domestic process monitoring. The Compton continuum from the dominant 661.7 keV 137Cs fission product peak obscures lower energy lines which could be used for spectral and multivariate analysis. Compton suppression may be able to mitigate the challenges posed by the high continuum caused by scattering. A Monte Carlo simulation using the Geant4 toolkit is being developed to predict the expected suppressed spectrum from spent fuel samples to estimate the reduction in the Compton continuum. Despite the lack of timing information between decay events in the particle management of Geant4, encouraging results were recorded utilizing only the information within individual decays without accounting for accidental coincidences. The model has been validated with single and cascade decay emitters in two steps: as an unsuppressed system and with suppression activated. Results of the Geant4 model validation will be presented.

  4. Lipocalin-2 inhibits osteoclast formation by suppressing the proliferation and differentiation of osteoclast lineage cells

    SciTech Connect (OSTI)

    Kim, Hyun-Ju; Yoon, Hye-Jin; Yoon, Kyung-Ae; Gwon, Mi-Ri; Jin Seong, Sook; Suk, Kyoungho; Kim, Shin-Yoon; Yoon, Young-Ran

    2015-06-10

    Lipocalin-2 (LCN2) is a member of the lipocalin superfamily and plays a critical role in the regulation of various physiological processes, such as inflammation and obesity. In this study, we report that LCN2 negatively modulates the proliferation and differentiation of osteoclast precursors, resulting in impaired osteoclast formation. The overexpression of LCN2 in bone marrow-derived macrophages or the addition of recombinant LCN2 protein inhibits the formation of multinuclear osteoclasts. LCN2 suppresses macrophage colony-stimulating factor (M-CSF)-induced proliferation of osteoclast precursor cells without affecting their apoptotic cell death. Interestingly, LCN2 decreases the expression of the M-CSF receptor, c-Fms, and subsequently blocks its downstream signaling cascades. In addition, LCN2 inhibits RANKL-induced osteoclast differentiation and attenuates the expression of c-Fos and nuclear factor of activated T cells c1 (NFATc1), which are important modulators in osteoclastogenesis. Mechanistically, LCN2 inhibits NF-κB signaling pathways, as demonstrated by the suppression of IκBα phosphorylation, nuclear translocation of p65, and NF-κB transcriptional activity. Thus, LCN2 is an anti-osteoclastogenic molecule that exerts its effects by retarding the proliferation and differentiation of osteoclast lineage cells. - Highlights: • LCN2 expression is regulated during osteoclast development. • LCN2 suppresses M-CSF-mediated osteoclast precursor proliferation. • LCN2 inhibits RANKL-induced osteoclast differentiation.

  5. Suppressing Manganese Dissolution from Lithium Manganese Oxide Spinel Cathodes with Single-Layer Graphene

    SciTech Connect (OSTI)

    Jaber-Ansari, Laila; Puntambekar, Kanan P.; Kim, Soo; Aykol, Muratahan; Luo, Langli; Wu, Jinsong; Myers, Benjamin D.; Iddir, Hakim; Russell, John T.; Saldana, Spencer J.; Kumar, Rajan; Thackeray, Michael M.; Curtiss, Larry A.; Dravid, Vinayak P.; Wolverton, Christopher M.; Hersam, Mark C.

    2015-06-24

    Spinel-structured LiMn 2 O 4 (LMO) is a desirable cathode material for Li-ion batteries due to its low cost, abundance, and high power capability. However, LMO suffers from limited cycle life that is triggered by manganese dissolution into the electrolyte during electrochemical cycling. Here, it is shown that single-layer graphene coatings suppress manganese dissolution, thus enhancing the performance and lifetime of LMO cathodes. Relative to lithium cells with uncoated LMO cathodes, cells with graphene-coated LMO cathodes provide improved capacity retention with enhanced cycling stability. X-ray photoelectron spectroscopy reveals that graphene coatings inhibit manganese depletion from the LMO surface. Additionally, transmission electron microscopy demonstrates that a stable solid electrolyte interphase is formed on graphene, which screens the LMO from direct contact with the electrolyte. Density functional theory calculations provide two mechanisms for the role of graphene in the suppression of manganese dissolution. First, common defects in single-layer graphene are found to allow the transport of lithium while concurrently acting as barriers for manganese diffusion. Second, graphene can chemically interact with Mn 3+ at the LMO electrode surface, promoting an oxidation state change to Mn 4+ , which suppresses dissolution.

  6. miR-17 inhibitor suppressed osteosarcoma tumor growth and metastasis via increasing PTEN expression

    SciTech Connect (OSTI)

    Gao, Yong; Luo, Ling-hui; Li, Shuai; Yang, Cao

    2014-02-07

    Highlights: • miR-17 was increased in OS tissues and cell lines. • Inhibition of miR-17 suppressed OS cell proliferation. • Inhibition of miR-17 suppressed OS cell migration and invasion. • PTEN was a target of miR-17. • miR-17 was negatively correlated with PTEN in OS tissues. - Abstract: MicroRNAs (miRNAs) play essential roles in cancer development and progression. Here, we investigated the role of miR-17 in the progression and metastasis of osteosarcoma (OS). miR-17 was frequently increased in OS tissues and cell lines. Inhibition of miR-17 in OS cell lines substantially suppressed cell proliferation, migration, and invasion. Phosphatase and tensin homolog (PTEN) was identified as a target of miR-17, and ectopic expression of miR-17 inhibited PTEN by direct binding to its 3′-untranslated region (3′-UTR). Expression of miR-17 was negatively correlated with PTEN in OS tissues. Together, these findings indicate that miR-17 acts as an oncogenic miRNA and may contribute to the progression and metastasis of OS, suggesting miR-17 as a potential novel diagnostic and therapeutic target of OS.

  7. Advances in the Understanding of ELM Suppression by Resonant Magnetic Perturbations (RMPs) in DIII-D and Implications for ITER

    SciTech Connect (OSTI)

    Nazikian, R.

    2014-09-01

    Experiments on DIII-D have expanding the operating window for RMP ELM suppression to higher q95 with dominant electron heating and fully non-inductive current drive relevant to advanced modes of ITER operation. Robust ELM suppression has also been obtained with a reduced coil set, mitigating the risk of coil failure in maintaining ELM suppression in ITER. These results significantly expand the operating space and reduce risk for obtaining RMP ELM suppression in ITER. Efforts have also been made to search for 3D cause of ELM suppression. No internal non-axisymmetric structure is detected at the top of the pedestal, indicating that the dominant effect of the RMP is to produce an n=0 transport modification of the profiles. Linear two fluid MHD simulations using M3D-C1 indicate resonant field penetration and significant magnetic stochasticity at the top of the pedestal, consistent with the absence of detectable 3D structure in that region. A profile database was developed to compare the scaling of the pedestal and global confinement with the applied 3D field strength in ELM suppressed and ELM mitigated plasmas. The EPED pedestal model accurately predicts the measured pedestal pressure at the threshold of ELM suppression, increasing confidence in theoretical projections to ITER pedestal conditions. Both the H-factor (H(sub)98y2) and thermal energy confinement time do not degrade substantially with applied RMP fields near the threshold of ELM suppression, enhancing confidence in the compatibility of ITER high performance operation with RMP ELM suppression.

  8. Suppression of dark current through barrier engineer for solution-processed colloidal quantum-dots infrared photodetectors

    SciTech Connect (OSTI)

    Jiang, Zhenyu E-mail: jianxu@engr.psu.edu; Liu, Yan; Mo, Chen; Wang, Li; Atalla, Mahmoud R. M.; Liu, Jie; Kurhade, Kandhar K.; Xu, Jian E-mail: jianxu@engr.psu.edu; Hu, Wenjia; Zhang, Wenjun; You, Guanjun; Zhang, Yu

    2015-08-31

    In an attempt to suppress the dark current, the barrier layer engineer for solution-processed PbSe colloidal quantum-dot (CQD) photodetectors has been investigated in the present study. It was found that the dark current can be significantly suppressed by implementing two types of carrier blocking layers, namely, hole blocking layer and electron blocking layer, sandwiched in between two active PbSe CQD layers. Meanwhile no adverse impact has been observed for the photo current. Our study suggests that this improvement resides on the transport pathway created via carrier recombination at intermediate layer, which provides wide implications for the suppression of dark current for infrared photodetectors.

  9. MOLECULAR MECHANISM OF SUPPRESSION OF NEOPLASTIC TRANSFORMATION BY LOW DOSES OF LOW LET RADIATION

    SciTech Connect (OSTI)

    J.LESIE REDPATH, PH.D.

    2011-03-29

    We are currently funded (9/01-8/04) by the DOE Low Dose Radiation Research Program to examine mechanisms underlying the suppression of neoplastic transformation in vitro by low doses of low LET radiation. For the new studies proposed under Notice 04-21, we intend to follow up on our observation that upregulation of DNA repair may be an important factor and that its importance is dose-dependent. The experimental system will be the human hybrid cell neoplastic transformation assay that we are currently using. We propose to test the following hypothesis: Down-regulation of DNA dsb repair will abrogate the low dose suppression of neoplastic transformation. Using the technique of RNA silencing, it is proposed to test the effect of down-regulation of the two major DNA dsb repair pathways, homologous recombination (HR) and non-homologous end-joining (NHEJ), on the dose response relationship for neoplastic transformation. Based on prior studies, we predict that this will result in abrogation of the suppressive effect at doses in the range 1 to 10 cGy, but not at lower doses. The proposed experiments will also help address the question as to which of the two DNA repair pathways may be the most important in causing suppression of transformation. HR is a pathway that is predominant in S and G2 phase cells and is known to be less error-prone than the NHEJ pathway that is predominant in G1 phase. We hypothesize that down-regulation of HR will result in the most effective abrogation of suppression. An important component of this study will be the determination of the how abrogation of DNA dsb repair impacts the spontaneous transformation frequency, presumably a consequence of endogeneous DNA damage. Experiments will be carried out using partially synchronized populations of cells enriched for G1 and S/G2 respectively. In addition to the endpoint of neoplastic transformation the impact of down-regulation of HR and NHEJ on the formation and disappearance of the DNA dsb marker

  10. RLIP76-dependent suppression of PI3K/AKT/Bcl-2 pathway by miR...

    Office of Scientific and Technical Information (OSTI)

    in prostate cancer Citation Details In-Document Search Title: RLIP76-dependent suppression of PI3KAKTBcl-2 pathway by miR-101 induces apoptosis in prostate cancer MicroRNA-101 ...

  11. RapTOR: Automated sequencing library preparation and suppression for rapid pathogen characterization ( 7th Annual SFAF Meeting, 2012)

    ScienceCinema (OSTI)

    Lane, Todd [SNL

    2013-02-11

    Todd Lane on "RapTOR: Automated sequencing library preparation and suppression for rapid pathogen characterization" at the 2012 Sequencing, Finishing, Analysis in the Future Meeting held June 5-7, 2012 in Santa Fe, New Mexico.

  12. p53 Mutation suppresses adult neurogenesis in medaka fish (Oryzias latipes)

    SciTech Connect (OSTI)

    Isoe, Yasuko; Okuyama, Teruhiro; Taniguchi, Yoshihito; Kubo, Takeo; Takeuchi, Hideaki

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer Progenitor migration is accompanied by an increase in their numbers in the adult brain. Black-Right-Pointing-Pointer p53 Mutation suppressed an increase in the number of the migrated progenitors. Black-Right-Pointing-Pointer The decreased progenitor number is not due to enhanced cell death. Black-Right-Pointing-Pointer p53 Mutation did not affect proliferation of stem cells. -- Abstract: Tumor suppressor p53 negatively regulates self-renewal of neural stem cells in the adult murine brain. Here, we report that the p53 null mutation in medaka fish (Oryzias latipes) suppressed neurogenesis in the telencephalon, independent of cell death. By using 5-bromo-29-deoxyuridine (BrdU) immunohistochemistry, we identified 18 proliferation zones in the brains of young medaka fish; in situ hybridization showed that p53 was expressed selectively in at least 12 proliferation zones. We also compared the number of BrdU-positive cells present in the whole telencephalon of wild-type (WT) and p53 mutant fish. Immediately after BrdU exposure, the number of BrdU-positive cells did not differ significantly between them. One week after BrdU-exposure, the BrdU-positive cells migrated from the proliferation zone, which was accompanied by an increased number in the WT brain. In contrast, no significant increase was observed in the p53 mutant brain. Terminal deoxynucleotidyl transferase (dUTP) nick end-labeling revealed that there was no significant difference in the number of apoptotic cells in the telencephalon of p53 mutant and WT medaka, suggesting that the decreased number of BrdU-positive cells in the mutant may be due to the suppression of proliferation rather than the enhancement of neural cell death. These results suggest that p53 positively regulates neurogenesis via cell proliferation.

  13. Strangeness suppression of qq¯ creation observed in exclusive reactions

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

    Mestayer, M. D.; Park, K.; Adhikari, K. P.; Aghasyan, M.; Pereira, S. Anefalos; Ball, J.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; et al

    2014-10-10

    In this study, we measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: ΛK+, pπ0, and nπ+, with the CLAS detector at Jefferson Lab. Using a simple model of quark hadronization, we extract qq¯ creation probabilities for the first time in exclusive two-body production, in which only a single qq¯ pair is created. We observe a sizable suppression of strange quark-antiquark pairs compared to nonstrange pairs, similar to that seen in high-energy production.

  14. Speckle noise suppression using a helix-free ferroelectric liquid crystal cell

    SciTech Connect (OSTI)

    Andreev, A L; Andreeva, T B; Kompanets, I N; Zalyapin, N V

    2014-12-31

    We have studied the method for suppressing speckle noise in patterns produced by a laser based on a fast-response electro-optical cell with a ferroelectric liquid crystal (FLC) in which helicoid is absent, i.e., compensated for. The character of smectic layer deformation in an electric field is considered along with the mechanism of spatially inhomogeneous phase modulation of a laser beam passing through the cell which is accompanied by the destruction of phase relations in the beam. Advantages of a helix-free FLC cell are pointed out as compared to helical crystal cells studied previously. (liquid crystal devices)

  15. Method and system for modulation of gain suppression in high average power laser systems

    DOE Patents [OSTI]

    Bayramian, Andrew James

    2012-07-31

    A high average power laser system with modulated gain suppression includes an input aperture associated with a first laser beam extraction path and an output aperture associated with the first laser beam extraction path. The system also includes a pinhole creation laser having an optical output directed along a pinhole creation path and an absorbing material positioned along both the first laser beam extraction path and the pinhole creation path. The system further includes a mechanism operable to translate the absorbing material in a direction crossing the first laser beam extraction laser path and a controller operable to modulate the second laser beam.

  16. Empirical Study Of Tube Wave Suppression For Single Well Seismic Imaging

    SciTech Connect (OSTI)

    West, Phillip Bradley; Weinberg, David Michael; Fincke, James Russell

    2002-05-01

    This report addresses the Idaho National Engineering and Environmental Laboratory's portion of a collaborative effort with Lawrence Berkeley National Laboratory and Sandia National Laboratories on a borehole seismic project called Single Well Seismic Imaging. The INEEL's role was to design, fabricate, deploy, and test a number of passive devices to suppress the energy within the borehole. This energy is generally known as tube waves. Heretofore, tube waves precluded acquisition of meaningful single-well seismic data. This report addresses the INEEL tests, theories, observations, and test results.

  17. Empirical Study Of Tube Wave Suppression For Single Well Seismic Imaging

    SciTech Connect (OSTI)

    West, P.B.; Weinberg, D.M.; Fincke, J.R.

    2002-05-31

    This report addresses the Idaho National Engineering and Environmental Laboratory's portion of a collaborative effort with Lawrence Berkeley National Laboratory and Sandia National Laboratories on a borehole seismic project called Single Well Seismic Imaging. The INEEL's role was to design, fabricate, deploy, and test a number of passive devices to suppress the energy within the borehole. This energy is generally known as tube waves. Heretofore, tube waves precluded acquisition of meaningful single-well seismic data. This report addresses the INEEL tests, theories, observations, and test results.

  18. Theory of suppressing avalanche process of carrier in short pulse laser irradiated dielectrics

    SciTech Connect (OSTI)

    Deng, Hongxiang; Zu, Xiaotao; Zheng, WG; Yuan, XD; Xiang, Xia; Sun, Kai; Gao, Fei

    2014-05-28

    A theory for controlling avalanche process of carrier during short pulse laser irradiation is proposed. We show that avalanche process of conduction band electrons (CBEs) is determined by the occupation number of phonons in dielectrics. The theory provides a way to suppress avalanche process and a direct judgment for the contribution of avalanche process and photon ionization process to the generation of CBEs. The obtained temperature dependent rate equation shows that the laser induced damage threshold of dielectrics, e.g., fused silica, increase nonlinearly with the decreases of temperature. Present theory predicts a new approach to improve the laser induced damage threshold of dielectrics.

  19. Dynamics of double layers, ion acceleration, and heat flux suppression during solar flares

    SciTech Connect (OSTI)

    Li, T. C.; Drake, J. F.; Swisdak, M.

    2014-09-20

    Observations of flare-heated electrons in the corona typically suggest confinement of electrons. The confinement mechanism, however, remains unclear. The transport of coronal hot electrons into ambient plasma was recently investigated by particle-in-cell (PIC) simulations. Electron transport was significantly suppressed by the formation of a highly localized, nonlinear electrostatic potential in the form of a double layer (DL). In this work large-scale PIC simulations are performed to explore the dynamics of DLs in larger systems where, instead of a single DL, multiple DLs are generated. The primary DL accelerates return current electrons, resulting in high velocity electron beams that interact with ambient ions. This forms a Buneman unstable system that spawns more DLs. Trapping of heated return current electrons between multiple DLs strongly suppresses electron transport. DLs also accelerate ambient ions and produce strong ion flows over an extended region. This clarifies the mechanism by which hot electrons in the corona couple to and accelerate ions to form the solar wind. These new dynamics in larger systems reveal a more likely picture of DL development and their impact on the ambient plasma in the solar corona. They are applicable to the preparation for in situ coronal space missions like the Solar Probe Plus.

  20. Preliminary conceptual design study of a suppressed-fission tokamak hybrid

    SciTech Connect (OSTI)

    Grady, D.; Berwald, D.; Garner, J.; Jassby, D.; Karbowski, J.; DeVan, J.; Lee, J.D.; Moir, R.W.

    1983-01-01

    A preliminary design concept for a commercial-size tokamak fusion breeder with a suppressed fission blanket and emphasis on /sup 233/U breeding has been formulated. The design is based upon a similar tandem mirror hybrid concept and addresses particular concerns relating to the use of a tokamak for the suppressed fission blanket application. The single most important departure from the tandem mirror reference blanket concept is the substitution of FLIBE for the liquid lithium used for cooling and in-situ tritium breeding. A concern for excessive MHD-related problems drove the decision to replace the more highly conductive lithium. As a result of the new coolant selection, material compatibility issues mandated changes in the composition of the mobile fuel pellets. In addition, the higher operating temperatures associated with the FLIBE placed more stringent constraints on structural requirements and reduced several design margins. Neutronics analyses predicted relatively poor blanket performance with tritium breeding of 1.02 and fissile /sup 233/U breeding of 0.34.

  1. Calculation of Fire Severity Factors and Fire Non-Suppression Probabilities For A DOE Facility Fire PRA

    SciTech Connect (OSTI)

    Tom Elicson; Bentley Harwood; Jim Bouchard; Heather Lucek

    2011-03-01

    Over a 12 month period, a fire PRA was developed for a DOE facility using the NUREG/CR-6850 EPRI/NRC fire PRA methodology. The fire PRA modeling included calculation of fire severity factors (SFs) and fire non-suppression probabilities (PNS) for each safe shutdown (SSD) component considered in the fire PRA model. The SFs were developed by performing detailed fire modeling through a combination of CFAST fire zone model calculations and Latin Hypercube Sampling (LHS). Component damage times and automatic fire suppression system actuation times calculated in the CFAST LHS analyses were then input to a time-dependent model of fire non-suppression probability. The fire non-suppression probability model is based on the modeling approach outlined in NUREG/CR-6850 and is supplemented with plant specific data. This paper presents the methodology used in the DOE facility fire PRA for modeling fire-induced SSD component failures and includes discussions of modeling techniques for: • Development of time-dependent fire heat release rate profiles (required as input to CFAST), • Calculation of fire severity factors based on CFAST detailed fire modeling, and • Calculation of fire non-suppression probabilities.

  2. Fission-suppressed fusion breeder on the thorium cycle and nonproliferation

    SciTech Connect (OSTI)

    Moir, R. W.

    2012-06-19

    Fusion reactors could be designed to breed fissile material while suppressing fissioning thereby enhancing safety. The produced fuel could be used to startup and makeup fuel for fission reactors. Each fusion reaction can produce typically 0.6 fissile atoms and release about 1.6 times the 14 MeV neutron's energy in the blanket in the fission-suppressed design. This production rate is 2660 kg/1000 MW of fusion power for a year. The revenues would be doubled from such a plant by selling fuel at a price of 60/g and electricity at $0.05/kWh for Q=P{sub fusion}/P{sub input}=4. Fusion reactors could be designed to destroy fission wastes by transmutation and fissioning but this is not a natural use of fusion whereas it is a designed use of fission reactors. Fusion could supply makeup fuel to fission reactors that were dedicated to fissioning wastes with some of their neutrons. The design for safety and heat removal and other items is already accomplished with fission reactors. Whereas fusion reactors have geometry that compromises safety with a complex and thin wall separating the fusion zone from the blanket zone where wastes could be destroyed. Nonproliferation can be enhanced by mixing {sup 233}U with {sup 238}U. Also nonproliferation is enhanced in typical fission-suppressed designs by generating up to 0.05 {sup 232}U atoms for each {sup 233}U atom produced from thorium, about twice the IAEA standards of 'reduced protection' or 'self protection.' With 2.4%{sup 232}U, high explosive material is predicted to degrade owing to ionizing radiation after a little over 1/2 year and the heat rate is 77 W just after separation and climbs to over 600 W ten years later. The fissile material can be used to fuel most any fission reactor but is especially appropriate for molten salt reactors (MSR) also called liquid fluoride thorium reactors (LFTR) because of the molten fuel does not need hands on fabrication and handling.

  3. Suppression of hepatic stellate cell activation by microRNA-29b

    SciTech Connect (OSTI)

    Sekiya, Yumiko; Ogawa, Tomohiro; Liver Research Center, Graduate School of Medicine, Osaka City University, Osaka ; Yoshizato, Katsutoshi; Liver Research Center, Graduate School of Medicine, Osaka City University, Osaka; PhoenixBio Co. Ltd., Hiroshima ; Ikeda, Kazuo; Kawada, Norifumi; Liver Research Center, Graduate School of Medicine, Osaka City University, Osaka

    2011-08-19

    Highlights: {yields} Expression of miR-29b was found to be down-regulated during the activation of hepatic stellate cells in primary culture. {yields} Transfection of a miR-29b precursor markedly attenuated the expression of Col1a1 and Col1a2 mRNAs. {yields} It blunted the increased expression of {alpha}-SMA, DDR2, FN1, ITGB1, and PDGFR-b mRNAs essential for stellate cell activation. {yields} miR-29b overexpression led stellate cells to remain in a quiescent state, as evidenced by their star-like morphology. {yields} miR-29b overexpression suppressed the expression of c-fos mRNA. -- Abstract: MicroRNAs (miRNAs) participate in the regulation of cellular functions including proliferation, apoptosis, and migration. It has been previously shown that the miR-29 family is involved in regulating type I collagen expression by interacting with the 3'UTR of its mRNA. Here, we investigated the roles of miR-29b in the activation of mouse primary-cultured hepatic stellate cells (HSCs), a principal collagen-producing cell in the liver. Expression of miR-29b was found to be down-regulated during HSC activation in primary culture. Transfection of a miR-29b precursor markedly attenuated the expression of Col1a1 and Col1a2 mRNAs and additionally blunted the increased expression of {alpha}-SMA, DDR2, FN1, ITGB1, and PDGFR-{beta}, which are key genes involved in the activation of HSCs. Further, overexpression of miR-29b led HSCs to remain in a quiescent state, as evidenced by their quiescent star-like cell morphology. Although phosphorylation of FAK, ERK, and Akt, and the mRNA expression of c-jun was unaffected, miR-29b overexpression suppressed the expression of c-fos mRNA. These results suggested that miR-29b is involved in the activation of HSCs and could be a candidate molecule for suppressing their activation and consequent liver fibrosis.

  4. Antibacterial agent triclosan suppresses RBL-2H3 mast cell function

    SciTech Connect (OSTI)

    Palmer, Rachel K.; Hutchinson, Lee M.; Burpee, Benjamin T.; Tupper, Emily J.; Pelletier, Jonathan H.; Kormendy, Zsolt; Hopke, Alex R.; Malay, Ethan T.; Evans, Brieana L.; Velez, Alejandro; Gosse, Julie A.

    2012-01-01

    Triclosan is a broad-spectrum antibacterial agent, which has been shown previously to alleviate human allergic skin disease. The purpose of this study was to investigate the hypothesis that the mechanism of this action of triclosan is, in part, due to effects on mast cell function. Mast cells play important roles in allergy, asthma, parasite defense, and carcinogenesis. In response to various stimuli, mast cells degranulate, releasing allergic mediators such as histamine. In order to investigate the potential anti-inflammatory effect of triclosan on mast cells, we monitored the level of degranulation in a mast cell model, rat basophilic leukemia cells, clone 2H3. Having functional homology to human mast cells, as well as a very well defined signaling pathway leading to degranulation, this cell line has been widely used to gain insight into mast-cell driven allergic disorders in humans. Using a fluorescent microplate assay, we determined that triclosan strongly dampened the release of granules from activated rat mast cells starting at 2 ?M treatment, with dose-responsive suppression through 30 ?M. These concentrations were found to be non-cytotoxic. The inhibition was found to persist when early signaling events (such as IgE receptor aggregation and tyrosine phosphorylation) were bypassed by using calcium ionophore stimulation, indicating that the target for triclosan in this pathway is likely downstream of the calcium signaling event. Triclosan also strongly suppressed F-actin remodeling and cell membrane ruffling, a physiological process that accompanies degranulation. Our finding that triclosan inhibits mast cell function may explain the clinical data mentioned above and supports the use of triclosan or a mechanistically similar compound as a topical treatment for allergic skin disease, such as eczema. -- Highlights: ?The effects of triclosan on mast cell function using a murine mast cell model. ?Triclosan strongly inhibits degranulation of mast cells. ?Triclosan

  5. CKM-suppressed top quark decays t{yields}s(d)+W in the standard model and beyond

    SciTech Connect (OSTI)

    Diaz-Cruz, J. L.; Gaitan-Lozano, R.; Castro, G. Lopez; Pagliarone, C. E.

    2008-05-01

    As it is well known, top quark decays are of particular interest as a means to test the standard model (SM) predictions, these include the dominant (t{yields}b+W), the Cabibbo-Kobayashi-Maskawa (CKM)-suppressed process t{yields}cWW, and the rare decays (t{yields}cV, cVV, c{phi}{sup 0}, bWZ). As all of them are highly suppressed, they become an excellent window to probe the predictions of theories beyond the SM. In this paper, we evaluate the corrections from new physics to the CKM-suppressed SM top quark decay t{yields}q+W(q=d,s), both within an effective model with right-handed currents and for the minimal SUSY extension of the SM. We also discuss the perspectives to probe those predictions at the International Linear Collider.

  6. Effect of power oscillations on suppression pool heating during ATWS (Anticipated Transients Without Scram) conditions

    SciTech Connect (OSTI)

    Wulff, W.; Cheng, H.S.; Mallen, A.N.

    1990-01-01

    Nine selected Anticipated Transients Without Scram (ATWS) have been simulated on the BNL Engineering Plant Analyzer (EPA), to determine how power and flow oscillations, similar to those that did or could have occurred at the LaSalle-2 boiling Water Reactor (BWR), could affect the rate of Pressure Suppression Pool heating. It has been determined that the pool can reach its temperature limit of 80{degree}C in 4.3 min. after Turbine Trip without Bypass, if the feedwater pumps are not tripped. The pool will not reach its limit, if Boron is injected, even when oscillations are encountered. Simultaneous turbine and recirculation pump trips, introduced under stable conditions, can lead to instability. 2 refs., 17 figs., 9 tabs.

  7. Suppression of low-frequency charge noise in gates-defined GaAs quantum dots

    SciTech Connect (OSTI)

    You, Jie; Li, Hai-Ou E-mail: gpguo@ustc.edu.cn; Wang, Ke; Cao, Gang; Song, Xiang-Xiang; Xiao, Ming; Guo, Guo-Ping E-mail: gpguo@ustc.edu.cn

    2015-12-07

    To reduce the charge noise of a modulation-doped GaAs/AlGaAs quantum dot, we have fabricated shallow-etched GaAs/AlGaAs quantum dots using the wet-etching method to study the effects of two-dimensional electron gas (2DEG) underneath the metallic gates. The low-frequency 1/f noise in the Coulomb blockade region of the shallow-etched quantum dot is compared with a non-etched quantum dot on the same wafer. The average values of the gate noise are approximately 0.5 μeV in the shallow-etched quantum dot and 3 μeV in the regular quantum dot. Our results show the quantum dot low-frequency charge noise can be suppressed by the removal of the 2DEG underneath the metallic gates, which provides an architecture for noise reduction.

  8. Radar signal pre-processing to suppress surface bounce and multipath

    DOE Patents [OSTI]

    Paglieroni, David W; Mast, Jeffrey E; Beer, N. Reginald

    2013-12-31

    A method and system for detecting the presence of subsurface objects within a medium is provided. In some embodiments, the imaging and detection system operates in a multistatic mode to collect radar return signals generated by an array of transceiver antenna pairs that is positioned across the surface and that travels down the surface. The imaging and detection system pre-processes that return signal to suppress certain undesirable effects. The imaging and detection system then generates synthetic aperture radar images from real aperture radar images generated from the pre-processed return signal. The imaging and detection system then post-processes the synthetic aperture radar images to improve detection of subsurface objects. The imaging and detection system identifies peaks in the energy levels of the post-processed image frame, which indicates the presence of a subsurface object.

  9. Extraordinary suppression of carrier scattering in large area graphene oxide films

    SciTech Connect (OSTI)

    Negishi, R. Kobayashi, Y.

    2014-12-22

    In this study, we find that thermal treatment in ethanol vapor has a remarkable suppression effect of carrier scattering occurring between reduced graphene oxide (rGO) flakes in large area films. We observe excellent electrical properties such as high carrier mobility (∼5 cm{sup 2}/Vs) and low sheet resistance (∼40 KΩ/□) for the rGO films. From the electrical conductivity analysis of large area rGO films using two-dimensional variable range hopping model and structural analysis using Raman spectra measured from the rGO films, we reveal that the significant effect is caused by the expansion of conjugated π-electron system in rGO flake due to the efficient restoration of graphitic structure.

  10. Inelastic collisions and density-dependent excitation suppression in a {sup 87}Sr optical lattice clock

    SciTech Connect (OSTI)

    Bishof, M.; Martin, M. J.; Swallows, M. D.; Benko, C.; Lin, Y.; Quemener, G.; Rey, A. M.; Ye, J.

    2011-11-15

    We observe two-body loss of {sup 3} P{sub 0} {sup 87}Sr atoms trapped in a one-dimensional optical lattice. We measure loss rate coefficients for atomic samples between 1 and 6 {mu}K that are prepared either in a single nuclear-spin sublevel or with equal populations in two sublevels. The measured temperature and nuclear-spin preparation dependence of rate coefficients agree well with calculations and reveal that rate coefficients for distinguishable atoms are only slightly enhanced over those of indistinguishable atoms. We further observe a suppression of excitation and losses during interrogation of the {sup 1} S{sub 0}-{sup 3} P{sub 0} transition as density increases and Rabi frequency decreases, which suggests the presence of strong interactions in our dynamically driven many-body system.

  11. Ionizing radiation from hydrogen recombination strongly suppresses the lithium scattering signature in the CMB

    SciTech Connect (OSTI)

    Switzer, Eric R.; Hirata, Christopher M.

    2005-10-15

    It has been suggested that secondary CMB anisotropies generated by neutral lithium could open a new observational window into the universe around the redshift z{approx}400, and permit a determination of the primordial lithium abundance. The effect is due to resonant scattering in the allowed Li i doublet (2s{sup 2}S{sub 1/2}-2p{sup 2}P{sub 1/2,3/2}), so its observability depends on the formation history of neutral lithium. Here we show that the ultraviolet photons produced during hydrogen recombination are sufficient to keep lithium in the Li ii ionization stage in the relevant redshift range and suppress the neutral fraction by {approx}3 orders of magnitude from previous calculations, making the lithium signature unobservable.

  12. Slag foaming phenomena and its suppression techniques in BOF steelmaking process

    SciTech Connect (OSTI)

    Pak, J.J.; Min, D.J.; You, B.D.

    1996-12-31

    Some basic studies using the X-ray fluoroscopy technique were carried out to understand slag foaming phenomena in BOF process. The BOF slag in contact with hot metal showed a generation of very fine size CO bubbles at the slag-metal interface, and formed a stable foam. The lump iron ore added into BOF slag decomposed faster, but showed less foaming than sinter ore did. The anti-foaming agent and coke were added into foamed BOF slag to compare their effectiveness of foam suppression. At the same time, various attempts were made to control the excessive slag foaming during BOF operation. Practice modifications such as oxygen blowing pattern and ore addition, and the installation of the slopping control button were effective and significantly reduced slopping. The slopping detection system involving oxygen lance vibration measurements were on-line installed for prompt and accurate control of slag foaming in BOF converter.

  13. J/{psi} and {psi}{prime} suppression in high-energy heavy-ion collisions

    SciTech Connect (OSTI)

    Wong, Cheuk-Yin

    1996-09-01

    The anomalous suppression of J/{psi} production in Pb-Pb collisions at 158 GeV observed by the NA50 Collaboration can be explained as due to the occurrence of a new phase of strong J/{psi} absorption, which sets in when the local energy density exceeds about 3.4 GeV/fm{sup 3}. The peculiar behavior of the {psi}{sup `}/{psi} ratio in {ital p}-A and nucleus-nucleus collisions can be understood as due to approximately equal {psi}-N and {psi}{sup `}-N absorption cross sections, but greater absorption cross sections for {psi}{sup `} than J/{psi} with regard to absorption by soft particles and matter in the new phase.

  14. 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.

  15. The FBXW7 {beta}-form is suppressed in human glioma cells

    SciTech Connect (OSTI)

    Gu, Zhaodi; Inomata, Kenichi; Ishizawa, Kota; Horii, Akira . E-mail: horii@mail.tains.tohoku.ac.jp

    2007-03-23

    FBXW7 (F-box and WD40 domain protein 7) is an F-box protein with 7 tandem WDs (tryptophan-aspartic acid) that functions as a phosphoepitope-specific substrate recognition component of SCF (Skp1-Cul1-F-box protein) ubiquitin ligases and catalyzes the ubiquitination of proteins promoting cell proliferation, such as CCNE1, MYC, AURKA, NOTCH1, and JUN, which are frequently activated in a wide range of human cancers. FBXW7 is a candidate tumor suppressor, and mutations have been reported in some human tumors. In this study, we analyzed 84 human tumor cell lines in search for genetic alterations of FBXW7, as well as mRNA and protein expressional changes, and compared them with expression levels of the CCNE1, MYC, and AURKA proteins. We found a novel nonsense mutation in a colon cancer cell line SCC and confirmed the missense mutations in SKOV3, an ovarian cancer cell line, and LoVo, a colon cancer cell line. Moreover, suppressed expression of FBXW7 accompanied by activation of the target proteins were observed in ovarian, colon, endometrial, gastric, and prostate cancers. It is notable that highly suppressed mRNA expression of the FBXW7 {beta}-form was found in all the human glioma cell lines analyzed; enhanced expressions of CCNE1, MYC, and AURKA were observed in these cells. Our present results imply that FBXW7 plays a pivotal role in many tissues by controlling the amount of cell cycle promoter proteins and that dysfunction of this protein is one of the essential steps in carcinogenesis in multiple organs.

  16. Deconfinement as an entropic self-destruction: A solution for the quarkonium suppression puzzle?

    SciTech Connect (OSTI)

    Kharzeev, Dmitri E.

    2014-10-02

    The entropic approach to dissociation of bound states immersed in strongly coupled systems is developed. In such systems, the excitations of the bound state are often delocalized and characterized by a large entropy, so that the bound state is strongly entangled with the rest of the statistical system. If this entropy S increases with the separation r between the constituents of the bound state, S=S(r), then the resulting entropic force F=T ∂S/∂r (T is temperature) can drive the dissociation process. As a specific example, we consider the case of heavy quarkonium in strongly coupled quark-gluon plasma, where lattice QCD indicates a large amount of entropy associated with the heavy quark pair at temperatures 0.9Tc ≤ T ≤ 1.5Tc (Tc is the deconfinement temperature); this entropy S(r) grows with the interquark distance r. We argue that the entropic mechanism results in an anomalously strong quarkonium suppression in the temperature range near Tc. This entropic self-destruction may thus explain why the experimentally measured quarkonium nuclear modification factor at RHIC (lower energy density) is smaller than at LHC (higher energy density), possibly resolving the “quarkonium suppression puzzle”—all of the previously known mechanisms of quarkonium dissociation operate more effectively at higher energy densities, and this contradicts the data. As a result, we find that near Tc the entropic force leads to delocalization of the bound hadron states; we argue that this delocalization may be the mechanism underlying deconfinement.

  17. An efficient modeling method for thermal stratification simulation in a BWR suppression pool

    SciTech Connect (OSTI)

    Haihua Zhao; Ling Zou; Hongbin Zhang; Hua Li; Walter Villanueva; Pavel Kudinov

    2012-09-01

    The suppression pool in a BWR plant not only is the major heat sink within the containment system, but also provides major emergency cooling water for the reactor core. In several accident scenarios, such as LOCA and extended station blackout, thermal stratification tends to form in the pool after the initial rapid venting stage. Accurately predicting the pool stratification phenomenon is important because it affects the peak containment pressure; and the pool temperature distribution also affects the NPSHa (Available Net Positive Suction Head) and therefore the performance of the pump which draws cooling water back to the core. Current safety analysis codes use 0-D lumped parameter methods to calculate the energy and mass balance in the pool and therefore have large uncertainty in prediction of scenarios in which stratification and mixing are important. While 3-D CFD methods can be used to analyze realistic 3D configurations, these methods normally require very fine grid resolution to resolve thin substructures such as jets and wall boundaries, therefore long simulation time. For mixing in stably stratified large enclosures, the BMIX++ code has been developed to implement a highly efficient analysis method for stratification where the ambient fluid volume is represented by 1-D transient partial differential equations and substructures such as free or wall jets are modeled with 1-D integral models. This allows very large reductions in computational effort compared to 3-D CFD modeling. The POOLEX experiments at Finland, which was designed to study phenomena relevant to Nordic design BWR suppression pool including thermal stratification and mixing, are used for validation. GOTHIC lumped parameter models are used to obtain boundary conditions for BMIX++ code and CFD simulations. Comparison between the BMIX++, GOTHIC, and CFD calculations against the POOLEX experimental data is discussed in detail.

  18. Simulation of Thermal Stratification in BWR Suppression Pools with One Dimensional Modeling Method

    SciTech Connect (OSTI)

    Haihua Zhao; Ling Zou; Hongbin Zhang

    2014-01-01

    The suppression pool in a boiling water reactor (BWR) plant not only is the major heat sink within the containment system, but also provides the major emergency cooling water for the reactor core. In several accident scenarios, such as a loss-of-coolant accident and extended station blackout, thermal stratification tends to form in the pool after the initial rapid venting stage. Accurately predicting the pool stratification phenomenon is important because it affects the peak containment pressure; the pool temperature distribution also affects the NPSHa (available net positive suction head) and therefore the performance of the Emergency Core Cooling System and Reactor Core Isolation Cooling System pumps that draw cooling water back to the core. Current safety analysis codes use zero dimensional (0-D) lumped parameter models to calculate the energy and mass balance in the pool; therefore, they have large uncertainties in the prediction of scenarios in which stratification and mixing are important. While three-dimensional (3-D) computational fluid dynamics (CFD) methods can be used to analyze realistic 3-D configurations, these methods normally require very fine grid resolution to resolve thin substructures such as jets and wall boundaries, resulting in a long simulation time. For mixing in stably stratified large enclosures, the BMIX++ code (Berkeley mechanistic MIXing code in C++) has been developed to implement a highly efficient analysis method for stratification where the ambient fluid volume is represented by one-dimensional (1-D) transient partial differential equations and substructures (such as free or wall jets) are modeled with 1-D integral models. This allows very large reductions in computational effort compared to multi-dimensional CFD modeling. One heat-up experiment performed at the Finland POOLEX facility, which was designed to study phenomena relevant to Nordic design BWR suppression pool including thermal stratification and mixing, is used for

  19. Substance P ameliorates collagen II-induced arthritis in mice via suppression of the inflammatory response

    SciTech Connect (OSTI)

    Hong, Hyun Sook; Son, Youngsook

    2014-10-10

    Highlights: • SP can increase IL-10 levels and reduce TNF-α and IL-17 levels in RA. • SP causes the increase in T{sub reg}, M2 macrophage, and MSCs in RA. • SP-induced immune suppression leads to the blockade of RA progression. • SP can be used as the therapeutics for autoimmune-related inflammatory diseases. - Abstract: Current rheumatoid arthritis (RA) therapies such as biologics inhibiting pathogenic cytokines substantially delay RA progression. However, patient responses to these agents are not always complete and long lasting. This study explored whether substance P (SP), an 11 amino acids long endogenous neuropeptide with the novel ability to mobilize mesenchymal stem cells (MSC) and modulate injury-mediated inflammation, can inhibit RA progression. SP efficacy was evaluated by paw swelling, clinical arthritis scoring, radiological analysis, histological analysis of cartilage destruction, and blood levels of tumor necrosis factor-alpha (TNF-α) interleukin (IL)-10, and IL-17 in vivo. SP treatment significantly reduced local inflammatory signs, mean arthritis scores, degradation of joint cartilage, and invasion of inflammatory cells into the synovial tissues. Moreover, the SP treatment markedly reduced the size of spleens enlarged by excessive inflammation in CIA, increased IL-10 levels, and decreased TNF-α and IL-17 levels. Mobilization of stem cells and induction of T{sub reg} and M2 type macrophages in the circulation were also increased by the SP treatment. These effect of SP might be associated with the suppression of inflammatory responses in RA and, furthermore, blockade of RA progression. Our results propose SP as a potential therapeutic for autoimmune-related inflammatory diseases.

  20. Deconfinement as an entropic self-destruction: A solution for the quarkonium suppression puzzle?

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

    Kharzeev, Dmitri E.

    2014-10-02

    The entropic approach to dissociation of bound states immersed in strongly coupled systems is developed. In such systems, the excitations of the bound state are often delocalized and characterized by a large entropy, so that the bound state is strongly entangled with the rest of the statistical system. If this entropy S increases with the separation r between the constituents of the bound state, S=S(r), then the resulting entropic force F=T ∂S/∂r (T is temperature) can drive the dissociation process. As a specific example, we consider the case of heavy quarkonium in strongly coupled quark-gluon plasma, where lattice QCD indicatesmore » a large amount of entropy associated with the heavy quark pair at temperatures 0.9Tc ≤ T ≤ 1.5Tc (Tc is the deconfinement temperature); this entropy S(r) grows with the interquark distance r. We argue that the entropic mechanism results in an anomalously strong quarkonium suppression in the temperature range near Tc. This entropic self-destruction may thus explain why the experimentally measured quarkonium nuclear modification factor at RHIC (lower energy density) is smaller than at LHC (higher energy density), possibly resolving the “quarkonium suppression puzzle”—all of the previously known mechanisms of quarkonium dissociation operate more effectively at higher energy densities, and this contradicts the data. As a result, we find that near Tc the entropic force leads to delocalization of the bound hadron states; we argue that this delocalization may be the mechanism underlying deconfinement.« less

  1. Decreases in Soil Moisture and Organic Matter Quality Suppress Microbial Decomposition Following a Boreal Forest Fire

    SciTech Connect (OSTI)

    Holden, Sandra R.; Berhe, Asmeret A.; Treseder, Kathleen K.

    2015-08-01

    Climate warming is projected to increase the frequency and severity of wildfires in boreal forests, and increased wildfire activity may alter the large soil carbon (C) stocks in boreal forests. Changes in boreal soil C stocks that result from increased wildfire activity will be regulated in part by the response of microbial decomposition to fire, but post-fire changes in microbial decomposition are poorly understood. Here, we investigate the response of microbial decomposition to a boreal forest fire in interior Alaska and test the mechanisms that control post-fire changes in microbial decomposition. We used a reciprocal transplant between a recently burned boreal forest stand and a late successional boreal forest stand to test how post-fire changes in abiotic conditions, soil organic matter (SOM) composition, and soil microbial communities influence microbial decomposition. We found that SOM decomposing at the burned site lost 30.9% less mass over two years than SOM decomposing at the unburned site, indicating that post-fire changes in abiotic conditions suppress microbial decomposition. Our results suggest that moisture availability is one abiotic factor that constrains microbial decomposition in recently burned forests. In addition, we observed that burned SOM decomposed more slowly than unburned SOM, but the exact nature of SOM changes in the recently burned stand are unclear. Finally, we found no evidence that post-fire changes in soil microbial community composition significantly affect decomposition. Taken together, our study has demonstrated that boreal forest fires can suppress microbial decomposition due to post-fire changes in abiotic factors and the composition of SOM. Models that predict the consequences of increased wildfires for C storage in boreal forests may increase their predictive power by incorporating the observed negative response of microbial decomposition to boreal wildfires.

  2. Apparatus for suppressing formation of vortices in the coolant fluid of a nuclear reactor and associated method

    DOE Patents [OSTI]

    Ekeroth, Douglas E.; Garner, Daniel C.; Hopkins, Ronald J.; Land, John T.

    1993-01-01

    An apparatus and method are provided for suppressing the formation of vortices in circulating coolant fluid of a nuclear reactor. A vortex-suppressing plate having a plurality of openings therein is suspended within the lower plenum of a reactor vessel below and generally parallel to the main core support of the reactor. The plate is positioned so as to intersect vortices which may form in the circulating reactor coolant fluid. The intersection of the plate with such vortices disrupts the rotational flow pattern of the vortices, thereby disrupting the formation thereof.

  3. Apparatus for suppressing formation of vortices in the coolant fluid of a nuclear reactor and associated method

    DOE Patents [OSTI]

    Ekeroth, D.E.; Garner, D.C.; Hopkins, R.J.; Land, J.T.

    1993-11-30

    An apparatus and method are provided for suppressing the formation of vortices in circulating coolant fluid of a nuclear reactor. A vortex-suppressing plate having a plurality of openings therein is suspended within the lower plenum of a reactor vessel below and generally parallel to the main core support of the reactor. The plate is positioned so as to intersect vortices which may form in the circulating reactor coolant fluid. The intersection of the plate with such vortices disrupts the rotational flow pattern of the vortices, thereby disrupting the formation thereof. 3 figures.

  4. Independent Oversight Review of the Technical Area 55 Safety Class Fire Suppression System at Los Alamos National Laboratory, December 2013

    Office of Environmental Management (EM)

    Technical Area 55 Safety Class Fire Suppression System at Los Alamos National Laboratory December 2013 Office of Safety and Emergency Management Evaluations Office of Enforcement and Oversight Office of Health, Safety and Security U.S. Department of Energy Table of Contents 1.0 Purpose .................................................................................................................................................... 1 2.0 Background

  5. Stratospheric ozone protection: The Montreal Protocol and Title VI of the Clean Air Act Amendments of 1990

    SciTech Connect (OSTI)

    Babst, C.R. III

    1993-08-01

    The stratospheric ozone layer protects the surface of the Earth from harmful ultraviolet (UV-B) radiation, which has been causally linked to skin cancer and cataracts, suppression of the human immune system, damage to crops and aquatic organisms, the formation of ground-level zone and the rapid weathering of outdoor plastics. In recent years, scientists have observed a significant deterioration of the ozone layer, particularly over the poles, but increasingly over populated regions as well. This deterioration has been attributed to the atmospheric release of certain man-made halocarbons, including chlorofluorocarbons (CFCs), halons, methyl chloroform and carbon tetrachloride. Once used extensively as propellants for aerosol sprays (but generally banned for such purposes since 1978), CFCs are widely used today as refrigerants, foams and solvents. All of these chlorinated (CFC, methyl chloroform and carbon tetrachloride) and brominated (halon) compounds are classified for regulatory purposes as Class I substances because of their significant ozone-depleting potential. Hydrochlorofluorocarbons (HCFCs), developed as alternatives to CFCs and halons for many different applications, have been classified for regulatory purposes as Class II substances because of their relatively less destructive impact on stratospheric ozone. This paper describes the following regulations to reduce destruction of the ozone layer: the Montreal Protocol; Title VI of the Clean air Act Amendments of 1990; Accelerated Phase-out schedules developed by the countries which signed the Montreal Protocol; Use restrictions; Recycling and Emission reduction requirements; Servicing of motor vehicle air conditions; ban on nonessential products; labeling requirements; safe alternatives. 6 refs.

  6. Intranuclear interactomic inhibition of NF-κB suppresses LPS-induced severe sepsis

    SciTech Connect (OSTI)

    Park, Sung-Dong; Cheon, So Yeong; Park, Tae-Yoon; Shin, Bo-Young; Oh, Hyunju; Ghosh, Sankar; Koo, Bon-Nyeo; Lee, Sang-Kyou

    2015-08-28

    Suppression of nuclear factor-κB (NF-κB) activation, which is best known as a major regulator of innate and adaptive immune responses, is a potent strategy for the treatment of endotoxic sepsis. To inhibit NF-κB functions, we designed the intra-nuclear transducible form of transcription modulation domain (TMD) of RelA (p65), called nt-p65-TMD, which can be delivered effectively into the nucleus without influencing the cell viability, and work as interactomic inhibitors via disruption of the endogenous p65-mediated transcription complex. nt-p65-TMD effectively inhibited the secretion of pro-inflammatory cytokines, including TNF-α, IL-1β, or IL-6 from BV2 microglia cells stimulated by lipopolysaccharide (LPS). nt-p65-TMD did not inhibit tyrosine phosphorylation of signaling mediators such as ZAP-70, p38, JNK, or ERK involved in T cell activation, but was capable of suppressing the transcriptional activity of NF-κB without the functional effect on that of NFAT upon T-cell receptor (TCR) stimulation. The transduced nt-p65-TMD in T cell did not affect the expression of CD69, however significantly inhibited the secretion of T cell-specific cytokines such as IL-2, IFN-γ, IL-4, IL-17A, or IL-10. Systemic administration of nt-p65-TMD showed a significant therapeutic effect on LPS-induced sepsis model by inhibiting pro-inflammatory cytokines secretion. Therefore, nt-p65-TMD can be a novel therapeutics for the treatment of various inflammatory diseases, including sepsis, where a transcription factor has a key role in pathogenesis, and further allows us to discover new functions of p65 under normal physiological condition without genetic alteration. - Highlights: • The nt-p65-TMD is intra-nuclear interactomic inhibitor of endogenous p65. • The nt-p65-TMD effectively inhibited the secretion of pro-inflammatory cytokines. • The excellent therapeutic potential of nt-p65-TMD was confirmed in sepsis model.

  7. miR-129 suppresses tumor cell growth and invasion by targeting PAK5 in hepatocellular carcinoma

    SciTech Connect (OSTI)

    Zhai, Jian; Qu, Shuping; Li, Xiaowei; Zhong, Jiaming; Chen, Xiaoxia; Qu, Zengqiang; Wu, Dong

    2015-08-14

    Emerging evidence suggests that microRNAs (miRNAs) play important roles in regulating HCC development and progression; however, the mechanisms by which their specific functions and mechanisms remained to be further explored. miR-129 has been reported in gastric cancers, lung cancer and colon cancer. In this study, we disclosed a new tumor suppresser function of miR-129 in HCC. We also found the downregulation of miR-129 occurred in nearly 3/4 of the tumors examined (56/76) compared with adjacent nontumorous tissues, which was more importantly, correlated to the advanced stage and vascular invasion. We then demonstrated that miR-129 overexpression attenuated HCC cells proliferation and invasion, inducing apoptosis in vitro. Moreover, we used miR-129 antagonist and found that anti-miR-129 promoted HCC cells malignant phenotypes. Mechanistically, our further investigations revealed that miR-129 suppressed cell proliferation and invasion by targeting the 3’-untranslated region of PAK5, as well as miR-129 silencing up-regulated PAK5 expression. Moreover, miR-129 expression was inversely correlated with PAK5 expression in 76 cases of HCC samples. RNA interference of PAK5 attenuated anti-miR-129 mediated cell proliferation and invasion in HCC cells. Taken together, these results demonstrated that miR-129 suppressed tumorigenesis and progression by directly targeting PAK5, defining miR-129 as a potential treatment target for HCC. - Highlights: • Decreased of miR-129 is found in HCC and associated with advanced stage and metastasis. • miR-129 suppresses proliferation and invasion of HCC cells. • miR-129 directly targets the 3′ UTR of PAK5 and diminishes PAK5 expression. • PAK5 is involved in miR-129 mediated suppression functions.

  8. Geraniin suppresses RANKL-induced osteoclastogenesis in vitro and ameliorates wear particle-induced osteolysis in mouse model

    SciTech Connect (OSTI)

    Xiao, Fei; Zhai, Zanjing; Jiang, Chuan; Liu, Xuqiang; Li, Haowei; Qu, Xinhua; Ouyang, Zhengxiao; Fan, Qiming; Tang, Tingting; Qin, An; Gu, Dongyun

    2015-01-01

    Wear particle-induced osteolysis and subsequent aseptic loosening remains the most common complication that limits the longevity of prostheses. Wear particle-induced osteoclastogenesis is known to be responsible for extensive bone erosion that leads to prosthesis failure. Thus, inhibition of osteoclastic bone resorption may serve as a therapeutic strategy for the treatment of wear particle induced osteolysis. In this study, we demonstrated for the first time that geraniin, an active natural compound derived from Geranium thunbergii, ameliorated particle-induced osteolysis in a Ti particle-induced mouse calvaria model in vivo. We also investigated the mechanism by which geraniin exerts inhibitory effects on osteoclasts. Geraniin inhibited RANKL-induced osteoclastogenesis in a dose-dependent manner, evidenced by reduced osteoclast formation and suppressed osteoclast specific gene expression. Specially, geraniin inhibited actin ring formation and bone resorption in vitro. Further molecular investigation demonstrated geraniin impaired osteoclast differentiation via the inhibition of the RANKL-induced NF-κB and ERK signaling pathways, as well as suppressed the expression of key osteoclast transcriptional factors NFATc1 and c-Fos. Collectively, our data suggested that geraniin exerts inhibitory effects on osteoclast differentiation in vitro and suppresses Ti particle-induced osteolysis in vivo. Geraniin is therefore a potential natural compound for the treatment of wear particle induced osteolysis in prostheses failure. - Highlights: • Geraniin suppresses osteoclasts formation and function in vitro. • Geraniin impairs RANKL-induced nuclear factor-κB and ERK signaling pathway. • Geraniin suppresses osteolysis in vivo. • Geraniin may be used for treating osteoclast related diseases.

  9. Environmental factors affecting long-term stabilization of radon suppression covers for uranium mill tailings

    SciTech Connect (OSTI)

    Young, J.K.; Long, L.W.; Reis, J.W.

    1982-04-01

    Pacific Northwest Laboratory is investigating the use of a rock armoring blanket (riprap) to mitigate wind and water erosion of an earthen radon suppression cover applied to uranium mill tailings. To help determine design stresses for the tailings piles, environmental parameters are characterized for the five active uranium-producing regions on a site-specific basis. Only conventional uranium mills that are currently operating or that are scheduled to open in the mid 1980s are considered. Available data indicate that flooding has the most potential for disrupting a tailings pile. The arid regions of the Wyoming Basins and the Colorado Plateau are subject to brief storms of high intensity. The Texas Gulf Coast has the highest potential for extreme precipitation from hurricane-related storms. Wind data indicate average wind speeds from 3 to 6 m/sec for the sites, but extremes of 40 m/sec can be expected. Tornado risks range from low to moderate. The Colorado Plateau has the highest seismic potential, with maximum acceleration caused by earthquakes ranging from 0.2 to 0.4 g. Any direct effect from volcanic eruption is negligible, as all mills are located 90 km or more from an igneous or hydrothermal system.

  10. Norathyriol Suppresses Skin Cancers Induced by Solar Ultraviolet Radiation by Targeting ERK Kinases

    SciTech Connect (OSTI)

    Li, Jixia; Malakhova, Margarita; Mottamal, Madhusoodanan; Reddy, Kanamata; Kurinov, Igor; Carper, Andria; Langfald, Alyssa; Oi, Naomi; Kim, Myoung Ok; Zhu, Feng; Sosa, Carlos P.; Zhou, Keyuan; Bode, Ann M.; Dong, Zigang

    2012-06-27

    Ultraviolet (UV) irradiation is the leading factor in the development of skin cancer, prompting great interest in chemopreventive agents for this disease. In this study, we report the discovery of norathyriol, a plant-derived chemopreventive compound identified through an in silico virtual screening of the Chinese Medicine Library. Norathyriol is a metabolite of mangiferin found in mango, Hypericum elegans, and Tripterospermum lanceolatum and is known to have anticancer activity. Mechanistic investigations determined that norathyriol acted as an inhibitor of extracellular signal-regulated kinase (ERK)1/2 activity to attenuate UVB-induced phosphorylation in mitogen-activated protein kinases signaling cascades. We confirmed the direct and specific binding of norathyriol with ERK2 through a cocrystal structural analysis. The xanthone moiety in norathyriol acted as an adenine mimetic to anchor the compound by hydrogen bonds to the hinge region of the protein ATP-binding site on ERK2. Norathyriol inhibited in vitro cell growth in mouse skin epidermal JB6 P+ cells at the level of G{sub 2}-M phase arrest. In mouse skin tumorigenesis assays, norathyriol significantly suppressed solar UV-induced skin carcinogenesis. Further analysis indicated that norathyriol mediates its chemopreventive activity by inhibiting the ERK-dependent activity of transcriptional factors AP-1 and NF-{kappa}B during UV-induced skin carcinogenesis. Taken together, our results identify norathyriol as a safe new chemopreventive agent that is highly effective against development of UV-induced skin cancer.

  11. SPARC-90: A code for calculating fission product capture in suppression pools

    SciTech Connect (OSTI)

    Owczarski, P.C.; Burk, K.W. )

    1991-10-01

    This report describes the technical bases and use of two updated versions of a computer code initially developed to serve as a tool for calculating aerosol particle retention in boiling water reactor (BWR) pressure suppression pools during severe accidents, SPARC-87 and SPARC-90. The most recent version is SPARC-90. The initial or prototype version (Owczarski, Postma, and Schreck 1985) was improved to include the following: rigorous treatment of local particle deposition velocities on the surface of oblate spherical bubbles, new correlations for hydrodynamic behavior of bubble swarms, models for aerosol particle growth, both mechanistic and empirical models for vent exit region scrubbing, specific models for hydrodynamics of bubble breakup at various vent types, and models for capture of vapor iodine species. A complete user's guide is provided for SPARC-90 (along with SPARC-87). A code description, code operating instructions, partial code listing, examples of the use of SPARC-90, and summaries of experimental data comparison studies also support the use of SPARC-90. 29 refs., 4 figs., 11 tabs.

  12. Variation in Use of Androgen Suppression With External-Beam Radiotherapy for Nonmetastatic Prostate Cancer

    SciTech Connect (OSTI)

    Swisher-McClure, Samuel; Pollack, Craig E.; Christodouleas, John P.; Guzzo, Thomas J.; Haas, Naomi B.; Vapiwala, Neha; Bekelman, Justin E.

    2012-05-01

    Purpose: To describe practice patterns associated with androgen suppression (AS) stratified by disease risk group in patients undergoing external-beam radiotherapy (EBRT) for localized prostate cancer. Methods and Materials: We identified 2,184 low-risk, 2,339 intermediate-risk, and 2,897 high-risk patients undergoing EBRT for nonmetastatic prostate cancer diagnosed between January 1, 2004, and December 31, 2005, in the linked Surveillance, Epidemiology, and End Results-Medicare database. We examined the association of patient, clinical, and demographic characteristics with AS use by multivariate logistic regression. Results: The proportions of patients receiving AS for low-risk, intermediate-risk, and high-risk prostate cancer were 32.2%, 56.3%, and 81.5%, respectively. AS use among men in the low-risk disease category varied widely, ranging from 13.6% in Detroit to 47.8% in Kentucky. We observed a significant decline in AS use between 2004 and 2005 within all three disease risk categories. Men aged {>=}75 years or with elevated comorbidity levels were more likely to receive AS. Conclusion: Our results identified apparent overuse and underuse of AS among men within the low-risk and high-risk disease categories, respectively. These results highlight the need for clinician and patient education regarding the appropriate use of AS. Practice patterns among intermediate-risk patients reflect the clinical heterogeneity of this population and underscore the need for better evidence to guide the treatment of these patients.

  13. Strategies to Suppress Cation Vacancies in Metal Oxide Alloys: Consequences for Solar Energy Conversion

    SciTech Connect (OSTI)

    Toroker, Maytal; Carter, Emily A.

    2015-09-01

    First-row transition metal oxides (TMOs) are promising alternative materials for inexpensive and efficient solar energy conversion. However, their conversion efficiency can be deleteriously affected by material imperfections, such as atomic vacancies. In this work, we provide examples showing that in some iron-containing TMOs, iron cation vacancy formation can be suppressed via alloying. We calculate within density functional theory+U theory the iron vacancy formation energy in binary rock-salt oxide alloys that contain iron, manganese, nickel, zinc, and/or magnesium. We demonstrate that formation of iron vacancies is less favorable if we choose to alloy iron(II) oxide with metals that cannot readily accept vacancy-generated holes, e.g., magnesium, manganese, nickel, or zinc. Since there are less available sites for holes and the holes are forced to reside on iron cations, the driving force for iron vacancy formation decreases. These results are consistent with an experiment observing a sharp drop in cation vacancy concentration upon alloying iron(II) oxide with manganese.

  14. Method and apparatus for suppressing regenerative instability and related chatter in machine tools

    DOE Patents [OSTI]

    Segalman, Daniel J.; Redmond, James M.

    2001-01-01

    Methods of and apparatuses for mitigating chatter vibrations in machine tools or components thereof. Chatter therein is suppressed by periodically or continuously varying the stiffness of the cutting tool (or some component of the cutting tool), and hence the resonant frequency of the cutting tool (or some component thereof). The varying of resonant frequency of the cutting tool can be accomplished by modulating the stiffness of the cutting tool, the cutting tool holder, or any other component of the support for the cutting tool. By periodically altering the impedance of the cutting tool assembly, chatter is mitigated. In one embodiment, a cyclic electric (or magnetic) field is applied to the spindle quill which contains an electro-rheological (or magneto-rheological) fluid. The variable yield stress in the fluid affects the coupling of the spindle to the machine tool structure, changing the natural frequency of oscillation. Altering the modal characteristics in this fashion disrupts the modulation of current tool vibrations with previous tool vibrations recorded on the workpiece surface.

  15. Method and apparatus for suppressing regenerative instability and related chatter in machine tools

    DOE Patents [OSTI]

    Segalman, Daniel J.; Redmond, James M.

    1999-01-01

    Methods of and apparatuses for mitigating chatter vibrations in machine tools or components thereof. Chatter therein is suppressed by periodically or continuously varying the stiffness of the cutting tool (or some component of the cutting tool), and hence the resonant frequency of the cutting tool (or some component thereof). The varying of resonant frequency of the cutting tool can be accomplished by modulating the stiffness of the cutting tool, the cutting tool holder, or any other component of the support for the cutting tool. By periodically altering the impedance of the cutting tool assembly, chatter is mitigated. In one embodiment, a cyclic electric (or magnetic) field is applied to the spindle quill which contains an electro-rheological (or magneto-rheological) fluid. The variable yield stress in the fluid affects the coupling of the spindle to the machine tool structure, changing the natural frequency of oscillation. Altering the modal characteristics in this fashion disrupts the modulation of current tool vibrations with previous tool vibrations recorded on the workpiece surface.

  16. Apparatus and method for suppressing vibration and displacement of a bellows

    DOE Patents [OSTI]

    Kuklo, T.C.

    1984-01-01

    Flexible bellows are utilized between two systems, such as a pumping system and a process station, to partially absorb system vibrations and to compensate for misalignment between the systems. It is common practice to either clamp a rigid spacer between flanges of the two systems to separate them from each other, or to maintain the bellows in unsupported relationship between these systems. In the former bellows arrangement, the rigid spacer transmits vibratory energy between the two systems and the bellows tends to function as an undamped or underdamped unit that resonates at its own frequency to create additional vibratory energy, transmitted to the systems. In the latter, unsupported bellows arrangement, the pressure differential prevalent between the fluid flowing through the bellows and ambient normally causes extension or retraction of the bellows and resulting misalignment problems. The present invention substantially solves the above vibration and misalignment problems by providing an inflatable tube in surrounding relationship about a bellows to suppress vibration and displacement thereof. A method for isolating first and second systems from each other to prevent the transmission of vibratory energy therebetween comprises the steps of attaching at least one flexible bellows between the systems, surrounding the bellows with an inflatable tube, and maintaining a predetermined pressure in the tube to urge the tube in flexible contact with at least some of the convolutions of the bellows.

  17. Apparatus and method for suppressing vibration and displacement of a bellows

    DOE Patents [OSTI]

    Kuklo, Thomas C.

    1985-01-01

    Flexible bellows are utilized between two systems, such as a pumping system and a process station, to partially absorb system vibrations and to compensate for misalignment between the systems. It is common practice to either clamp a rigid spacer between flanges of the two systems (FIG. 3B) to separate them from each other, or to maintain the bellows in unsupported relationship between these systems (FIG. 4B). In the former bellows arrangement, the rigid spacer transmits vibratory energy between the two systems and the bellows tends to function as an undamped or underdamped unit that resonates at its own frequency to create additional vibratory energy, transmitted to the systems. In the latter, unsupported bellows arrangement (FIG. 4B), the pressure differential prevalent between the fluid flowing through the bellows and ambient normally causes extension or retraction of the bellows and resulting misalignment problems. The present invention substantially solves the above vibration and misalignment problems by providing an inflatable tube (20) in surrounding relationship about a bellows (14) to suppress vibration and displacement thereof. A method for isolating first and second systems (11,12) from each other to prevent the transmission of vibratory energy therebetween comprises the steps of attaching at least one flexible bellows (14) between the systems (11,12), surrounding the bellows with an inflatable tube (20), and maintaining a predetermined pressure in the tube (20) to urge the tube in flexible contact with at least some of the convolutions of the bellows (14).

  18. Vibration suppression in cutting tools using collocated piezoelectric sensors/actuators with an adaptive control algorithm

    SciTech Connect (OSTI)

    Radecki, Peter P; Farinholt, Kevin M; Park, Gyuhae; Bement, Matthew T

    2008-01-01

    The machining process is very important in many engineering applications. In high precision machining, surface finish is strongly correlated with vibrations and the dynamic interactions between the part and the cutting tool. Parameters affecting these vibrations and dynamic interactions, such as spindle speed, cut depth, feed rate, and the part's material properties can vary in real-time, resulting in unexpected or undesirable effects on the surface finish of the machining product. The focus of this research is the development of an improved machining process through the use of active vibration damping. The tool holder employs a high bandwidth piezoelectric actuator with an adaptive positive position feedback control algorithm for vibration and chatter suppression. In addition, instead of using external sensors, the proposed approach investigates the use of a collocated piezoelectric sensor for measuring the dynamic responses from machining processes. The performance of this method is evaluated by comparing the surface finishes obtained with active vibration control versus baseline uncontrolled cuts. Considerable improvement in surface finish (up to 50%) was observed for applications in modern day machining.

  19. Effectively suppressing dissolution of manganese from spinel lithium manganate via a nanoscale surface-doping approach

    SciTech Connect (OSTI)

    Lu, Jun; Zhan, Chun; Wu, Tianpin; Wen, Jianguo; Lei, Yu; Kropf, A. Jeremy; Wu, Huiming; Miller, Dean J.; Elam, Jeffrey W.; Sun, Yang-Kook; Qiu, Xinping; Amine, Khalil

    2014-12-16

    The capacity fade of lithium manganate-based cells is associated with the dissolution of Mn from cathode/electrolyte interface due to the disproportionation reaction of Mn(III), and the subsequent deposition of Mn(II) on the anode. Suppressing the dissolution of Mn from the cathode is critical to reducing capacity fade of LiMn2O4-based cells. Here we report a nanoscale surface-doping approach that minimizes Mn dissolution from lithium manganate. This approach exploits advantages of both bulk doping and surface-coating methods by stabilizing surface crystal structure of lithium manganate through cationic doping while maintaining bulk lithium manganate structure, and protecting bulk lithium manganate from electrolyte corrosion while maintaining ion and charge transport channels on the surface through the electrochemically active doping layer. Consequently, the surface-doped lithium manganate demonstrates enhanced electrochemical performance. This study provides encouraging evidence that surface doping could be a promising alternative to improve the cycling performance of lithium-ion batteries.

  20. Methods And System Suppressing Clutter In A Gain-Block, Radar-Responsive Tag System

    DOE Patents [OSTI]

    Ormesher, Richard C.; Axline, Robert M.

    2006-04-18

    Methods and systems reduce clutter interference in a radar-responsive tag system. A radar transmits a series of linear-frequency-modulated pulses and receives echo pulses from nearby terrain and from radar-responsive tags that may be in the imaged scene. Tags in the vicinity of the radar are activated by the radar's pulses. The tags receive and remodulate the radar pulses. Tag processing reverses the direction, in time, of the received waveform's linear frequency modulation. The tag retransmits the remodulated pulses. The radar uses a reversed-chirp de-ramp pulse to process the tag's echo. The invention applies to radar systems compatible with coherent gain-block tags. The invention provides a marked reduction in the strength of residual clutter echoes on each and every echo pulse received by the radar. SAR receiver processing effectively whitens passive-clutter signatures across the range dimension. Clutter suppression of approximately 14 dB is achievable for a typical radar system.

  1. Suppression of autophagy enhances the cytotoxicity of the DNA-damaging aromatic amine p-anilinoaniline

    SciTech Connect (OSTI)

    Elliott, Althea; Reiners, John J.

    2008-10-15

    p-Anilinoaniline (pAA) is an aromatic amine that is widely used in hair dying applications. It is also a metabolite of metanil yellow, an azo dye that is commonly used as a food coloring agent. Concentrations of pAA between 10 and 25 {mu}M were cytostatic to cultures of the normal human mammary epithelia cell line MCF10A. Concentrations {>=} 50 {mu}M were cytotoxic. Cytostatic concentrations induced transient G{sub 1} and S cell cycle phase arrests; whereas cytotoxic concentrations induced protracted arrests. Cytotoxic concentrations of pAA caused DNA damage, as monitored by the alkaline single-cell gel electrophoresis (Comet) assay, and morphological changes consistent with cells undergoing apoptosis and/or autophagy. Enzymatic and western blot analyses, and binding analyses of fluorescent labeled VAD-FMK, suggested that caspase family members were activated by pAA. Western blot analyses documented the conversion of LC3-I to LC3-II, a post-translational modification involved in the development of the autophagosome. Suppression of autophagosome formation, via knockdown of ATG7 with shRNA, prevented pAA-induced vacuolization, enhanced the activation of pro-caspase-3, and increased susceptibility of ATG7-deficient cells to the cytostatic and cytotoxic activities of markedly lower concentrations of pAA. Cells stably transfected with a nonsense shRNA behaved like parental MCF10A cells. Collectively, these data suggest that MCF10A cultures undergo autophagy as a pro-survival response to concentrations of pAA sufficient to induce DNA damage.

  2. Search for CP violation in singly Cabibbo suppressed four-body D decays

    SciTech Connect (OSTI)

    Martinelli, Maurizio; /Bari U.

    2011-06-22

    We search for CP violation in a sample of 4.7 x 10{sup 4} singly Cabibbo suppressed D{sup 0} {yields} K{sup +} K{sup -} {pi}{sup +}{pi}{sup -} decays and 1.8(2.6) x 10{sup 4} D{sub (s)}{sup +} {yields} K{sub S}{sup 0} K{sup +} {pi}{sup +} {pi}{sup -} decays. CP violation is searched for in the difference between the T-odd asymmetries, obtained using triple product correlations, measured for D and {bar D} decays. The measured CP violation parameters are A{sub T}(D{sup 0}) = (1.0 {+-} 5.1(stat) {+-} 4.4(syst)) x 10{sup -3}, A{sub T}(D{sup +}) = (-11.96 {+-} 10.04(stat) {+-} 4.81(syst)) x 10{sup -3} and A{sub T}(D{sub s}{sup +}) = (-13.57 {+-} 7.67(stat) {+-} 4.82(syst)) x 10{sup -3}. This search for CP violation showed that the T-odd correlations are a powerful tool to measure the CP violating observable A{sub T}. The relative simplicity of an analysis based on T-odd correlations and the high quality results that can be obtained, allow to consider this tool as fundamental to search for CP violation in four-body decays. Even if the CP violation has not been found, excluding any New Physics effect to the sensitivity of about 0.5%, it is still worth to search for CP violation in D decays. The high statistics that can be obtained at the LHC or by the proposed high luminosity B-factories, make this topic to be considered in high consideration by experiments such as LHCb, SuperB or SuperBelle. The results outlined in this thesis strongly suggest to include a similar analysis into the Physics program of these experiments.

  3. MicroRNAs Suppress NB Domain Genes in Tomato That Confer Resistance to Fusarium oxysporum

    SciTech Connect (OSTI)

    Ouyang, Shouqiang; Park, Gyungsoon; Atamian, Hagop S.; Han, Cliff S.; Stajich, Jason E.; Kaloshian, Isgouhi; Borkovich, Katherine A.

    2014-10-16

    MicroRNAs (miRNAs) suppress the transcriptional and post-transcriptional expression of genes in plants. Several miRNA families target genes encoding nucleotide-binding site–leucine-rich repeat (NB-LRR) plant innate immune receptors. The fungus Fusarium oxysporum f. sp. lycopersici causes vascular wilt disease in tomato. Here, we explored a role for miRNAs in tomato defense against F. oxysporum using comparative miRNA profiling of susceptible (Moneymaker) and resistant (Motelle) tomato cultivars. slmiR482f and slmiR5300 were repressed during infection of Motelle with F. oxysporum. Two predicted mRNA targets each of slmiR482f and slmiR5300 exhibited increased expression in Motelle and the ability of these four targets to be regulated by the miRNAs was confirmed by co-expression in Nicotiana benthamiana. Silencing of the targets in the resistant Motelle cultivar revealed a role in fungal resistance for all four genes. All four targets encode proteins with full or partial nucleotide-binding (NB) domains. One slmiR5300 target corresponds to tm-2, a susceptible allele of the Tomato Mosaic Virus resistance gene, supporting functions in immunity to a fungal pathogen. The observation that none of the targets correspond to I-2, the only known resistance (R) gene for F. oxysporum in tomato, supports roles for additional R genes in the immune response. In conclusion, taken together, our findings suggest that Moneymaker is highly susceptible because its potential resistance is insufficiently expressed due to the action of miRNAs.

  4. Preventing cleavage of Mer promotes efferocytosis and suppresses acute lung injury in bleomycin treated mice

    SciTech Connect (OSTI)

    Lee, Ye-Ji; Lee, Seung-Hae; Youn, Young-So; Choi, Ji-Yeon; Song, Keung-Sub; Cho, Min-Sun; Kang, Jihee Lee

    2012-08-15

    Mer receptor tyrosine kinase (Mer) regulates macrophage activation and promotes apoptotic cell clearance. Mer activation is regulated through proteolytic cleavage of the extracellular domain. To determine if membrane-bound Mer is cleaved during bleomycin-induced lung injury, and, if so, how preventing the cleavage of Mer enhances apoptotic cell uptake and down-regulates pulmonary immune responses. During bleomycin-induced acute lung injury in mice, membrane-bound Mer expression decreased, but production of soluble Mer and activity as well as expression of disintegrin and metalloproteinase 17 (ADAM17) were enhanced . Treatment with the ADAM inhibitor TAPI-0 restored Mer expression and diminished soluble Mer production. Furthermore, TAPI-0 increased Mer activation in alveolar macrophages and lung tissue resulting in enhanced apoptotic cell clearance in vivo and ex vivo by alveolar macrophages. Suppression of bleomycin-induced pro-inflammatory mediators, but enhancement of hepatocyte growth factor induction were seen after TAPI-0 treatment. Additional bleomycin-induced inflammatory responses reduced by TAPI-0 treatment included inflammatory cell recruitment into the lungs, levels of total protein and lactate dehydrogenase activity in bronchoalveolar lavage fluid, as well as caspase-3 and caspase-9 activity and alveolar epithelial cell apoptosis in lung tissue. Importantly, the effects of TAPI-0 on bleomycin-induced inflammation and apoptosis were reversed by coadministration of specific Mer-neutralizing antibodies. These findings suggest that restored membrane-bound Mer expression by TAPI-0 treatment may help resolve lung inflammation and apoptosis after bleomycin treatment. -- Highlights: ►Mer expression is restored by TAPI-0 treatment in bleomycin-stimulated lung. ►Mer signaling is enhanced by TAPI-0 treatment in bleomycin-stimulated lung. ►TAPI-0 enhances efferocytosis and promotes resolution of lung injury.

  5. Carbamazepine suppresses calpain-mediated autophagy impairment after ischemia/reperfusion in mouse livers

    SciTech Connect (OSTI)

    Kim, Jae-Sung, E-mail: Jae.Kim@surgery.ufl.edu; Wang, Jin-Hee, E-mail: jin-hee.wang@surgery.ufl.edu; Biel, Thomas G., E-mail: Thomas.Biel@surgery.ufl.edu; Kim, Do-Sung, E-mail: do-sung.kim@surgery.med.ufl.edu; Flores-Toro, Joseph A., E-mail: Joseph.Flores-Toro@surgery.ufl.edu; Vijayvargiya, Richa, E-mail: rvijayvargiya@ufl.edu; Zendejas, Ivan, E-mail: ivan.zendejas@surgery.ufl.edu; Behrns, Kevin E., E-mail: Kevin.Behrns@surgery.ufl.edu

    2013-12-15

    Onset of the mitochondrial permeability transition (MPT) plays a causative role in ischemia/reperfusion (I/R) injury. Current therapeutic strategies for reducing reperfusion injury remain disappointing. Autophagy is a lysosome-mediated, catabolic process that timely eliminates abnormal or damaged cellular constituents and organelles such as dysfunctional mitochondria. I/R induces calcium overloading and calpain activation, leading to degradation of key autophagy-related proteins (Atg). Carbamazepine (CBZ), an FDA-approved anticonvulsant drug, has recently been reported to increase autophagy. We investigated the effects of CBZ on hepatic I/R injury. Hepatocytes and livers from male C57BL/6 mice were subjected to simulated in vitro, as well as in vivo I/R, respectively. Cell death, intracellular calcium, calpain activity, changes in autophagy-related proteins (Atg), autophagic flux, MPT and mitochondrial membrane potential after I/R were analyzed in the presence and absence of 20 ?M CBZ. CBZ significantly increased hepatocyte viability after reperfusion. Confocal microscopy revealed that CBZ prevented calcium overloading, the onset of the MPT and mitochondrial depolarization. Immunoblotting and fluorometric analysis showed that CBZ blocked calpain activation, depletion of Atg7 and Beclin-1 and loss of autophagic flux after reperfusion. Intravital multiphoton imaging of anesthetized mice demonstrated that CBZ substantially reversed autophagic defects and mitochondrial dysfunction after I/R in vivo. In conclusion, CBZ prevents calcium overloading and calpain activation, which, in turn, suppresses Atg7 and Beclin-1 depletion, defective autophagy, onset of the MPT and cell death after I/R. - Highlights: A mechanism of carbamazepine (CBZ)-induced cytoprotection in livers is proposed. Impaired autophagy is a key event contributing to lethal reperfusion injury. The importance of autophagy is extended and confirmed in an in vivo model. CBZ is a potential agent to

  6. Protein A suppresses immune responses during Staphylococcus aureus bloodstream infection in guinea pigs

    SciTech Connect (OSTI)

    Kim, Hwan Keun; Falugi, Fabiana; Thomer, Lena; Missiakas, Dominique M.; Schneewind, Olaf

    2015-01-06

    Staphylococcus aureus infection is not associated with the development of protective immunity, and disease relapses occur frequently. We hypothesize that protein A, a factor that binds immunoglobulin Fcγ and cross-links VH3 clan B cell receptors (IgM), is the staphylococcal determinant for host immune suppression. To test this, vertebrate IgM was examined for protein A cross-linking. High VH3 binding activity occurred with human and guinea immunoglobulin, whereas mouse and rabbit immunoglobulins displayed little and no binding, respectively. Establishing a guinea pig model of S. aureus bloodstream infection, we show that protein A functions as a virulence determinant and suppresses host B cell responses. Immunization with SpAKKAA, which cannot bind immunoglobulin, elicits neutralizing antibodies that enable guinea pigs to develop protective immunity.

  7. Background Suppression Using Pulse Shape Analysis with a BEGe Detector for Neutrinoless Double Beta Decay Search with GERDA

    SciTech Connect (OSTI)

    Budjas, Dusan; Schoenert, Stefan [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Chkvorets, Oleg [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Department of Physics, Laurentian University, Ramsey Lake Road, P3E 2C6 Sudbury, Ontario (Canada)

    2009-12-17

    A pulse shape analysis for distinguishing between double beta decay-like interactions and multiple-scattered photons was performed for the first time using a BEGe-type detector. This discrimination method is included in the research and development for the second phase of the GERDA experiment, since active background suppression techniques are necessary to reach sensitivity for the {sup 76}Ge neutrinoless double beta decay half life of >10{sup 26} years. A suppression of backgrounds in the energy region of interest around the {sup 76}Ge Q{sub {beta}}{sub {beta}} = 2039 keV is demonstrated, with (0.93{+-}0.08)% survival probability for events from {sup 60}Co, (21{+-}3)% for {sup 226}Ra, and (40{+-}2)% for {sup 228}Th. This performance is achieved with (89{+-}1)% acceptance of {sup 228}Th double escape events, which are analogous to double beta decay.

  8. Kurarinol induces hepatocellular carcinoma cell apoptosis through suppressing cellular signal transducer and activator of transcription 3 signaling

    SciTech Connect (OSTI)

    Shu, Guangwen; Yang, Jing; Zhao, Wenhao; Xu, Chan; Hong, Zongguo; Mei, Zhinan; Yang, Xinzhou

    2014-12-01

    Kurarinol is a flavonoid isolated from roots of the medical plant Sophora flavescens. However, its cytotoxic activity against hepatocellular carcinoma (HCC) cells and toxic effects on mammalians remain largely unexplored. Here, the pro-apoptotic activities of kurarinol on HCC cells and its toxic impacts on tumor-bearing mice were evaluated. The molecular mechanisms underlying kurarinol-induced HCC cell apoptosis were also investigated. We found that kurarinol dose-dependently provoked HepG2, Huh-7 and H22 HCC cell apoptosis. In addition, kurarinol gave rise to a considerable decrease in the transcriptional activity of signal transducer and activator of transcription 3 (STAT3) in HCC cells. Suppression of STAT3 signaling is involved in kurarinol-induced HCC cell apoptosis. In vivo studies showed that kurarinol injection substantially induced transplanted H22 cell apoptosis with low toxic impacts on tumor-bearing mice. Similarly, the transcriptional activity of STAT3 in transplanted tumor tissues was significantly suppressed after kurarinol treatment. Collectively, our current research demonstrated that kurarinol has the capacity of inducing HCC cell apoptosis both in vitro and in vivo with undetectable toxic impacts on the host. Suppressing STAT3 signaling is implicated in kurarinol-mediated HCC cell apoptosis. - Highlights: • Kurarinol induces hepatocellular carcinoma (HCC) cell apoptosis. • Kurarinol induces HCC cell apoptosis via inhibiting STAT3. • Kurarinol exhibits low toxic effects on tumor-bearing animals.

  9. Transverse momentum and centrality dependence of high-ptnon-photonic electron suppression in Au+Au collisions at $\\sqrt{s_{NN}}$= 200 GeV

    SciTech Connect (OSTI)

    Abelev, B.I.; Adams, J.; Aggarwal, M.M.; Ahammed, Z.; Amonett,J.; Anderson, B.D.; Anderson, M.; Arkhipkin, D.; Averichev, G.S.; Bai,Y.; Balewski, J.; Barannikova, O.; Barnby, L.S.; Baudot, J.; Bekele, S.; Belaga, V.V.; Bellingeri-Laurikainen, A.; Bellwied, R.; Benedosso, F.; Bhardwaj, S.; Bhasin, A.; Bhati, A.K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L.C.; Blyth, S.-L.; Bonner, B.E.; Botje, M.; Bouchet, J.; Brandin, A.V.; Bravar, A.; Bystersky, M.; Cadman, R.V.; Cai,X.Z.; Caines, H.; Calderon de la Barca Sanchez, M.; Castillo, J.; Catu,O.; Cebra, D.; Chajecki, Z.; Chaloupka, P.; Chattopadhyay, S.; Chen,H.F.; Chen, J.H.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Coffin, J.P.; Cormier, T.M.; Cosentino, M.R.; Cramer, J.G.; Crawford,H.J.; Das, D.; Das, S.; Daugherity, M.; de Moura, M.M.; Dedovich, T.G.; DePhillips, M.; Derevschikov, A.A.; Didenko, L.; Dietel, T.; Djawotho,P.; Dogra, S.M.; Dong, W.J.; Dong, X.; Draper, J.E.; Du, F.; Dunin, V.B.; Dunlop, J.C.; Dutta Mazumdar, M.R.; Eckardt, V.; Edwards, W.R.; Efimov,L.G.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Fatemi, R.; Fedorisin, J.; Filimonov, K.; Filip, P.; Finch,E.; Fine, V.; Fisyak, Y.; Fu, J.; Gagliardi, C.A.; Gaillard, L.; Ganti,M.S.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, J.S.; Gorbunov, Y.G.; Gos,H.; Grebenyuk, O.; Grosnick, D.; Guertin, S.M.; Guimaraes, K.S.F.F.; Guo,Y.; Gupta, N.; Gutierrez, T.D.; Haag, B.; Hallman, T.J.; Hamed, A.; Harris, J.W.; He, W.; Heinz, M.; Henry, T.W.; Hepplemann, S.; Hippolyte,B.; Hirsch, A.; Hjort, E.; Hoffman, A.M.; Hoffmann, G.W.; Horner, M.J.; Huang, H.Z.; Huang, S.L.; Hughes, E.W.; Humanic, T.J.; Igo, G.; Jacobs,P.; Jacobs, W.W.; Jakl, P.; Jia, F.; Jiang, H.; Jones, P.G.; Judd, E.G.; Kabana, S.; Kang, K.; Kapitan, J.; Kaplan, M.; Keane, D.; Kechechyan, A.; Khodyrev, V.Yu.; Kim, B.C.; Kiryluk, J.; Kisiel, A.; Kislov, E.M.; Klein,S.R.; Kocoloski, A.; Koetke, D.D.; et al.

    2006-07-11

    The STAR collaboration at RHIC reports measurements of theinclusive yield of non-photonic electrons, which arise dominantly fromsemi-leptonic decays of heavy flavor mesons, over a broad range oftransverse momenta (1.2suppression in central AuAu collisions athigh pt, suggesting substantial heavy quark energy loss at RHIC. Thecentrality and \\pt dependences of the suppression provide constraints ontheoretical models of suppression.

  10. Novel Americium Treatment Process for Surface Water and Dust Suppression Water

    SciTech Connect (OSTI)

    Tiepel, E.W.; Pigeon, P.; Nesta, S.; Anderson, J.

    2006-07-01

    -241 contaminated pond water, surface run-off and D and D dust suppression water during the later stages of the D and D effort at Rocky Flats. This novel chemical treatment system allowed for highly efficient, high-volume treatment of all contaminated waste waters to the very low stream standard of 0.15 pCi/1 with strict compliance to the RFCA discharge criteria for release to off-site surface waters. The rapid development and implementation of the treatment system avoided water management issues that would have had to be addressed if contaminated water had remained in Pond A-4 into the Spring of 2005. Implementation of this treatment system for the Pond A-4 waters and the D and D waters from Buildings 776 and 371 enabled the site to achieve cost-effective treatment that minimized secondary waste generation, avoiding the need for expensive off-site water disposal. Water treatment was conducted for a cost of less than $0.20/gal which included all development costs, capital costs and operational costs. This innovative and rapid response effort saved the RFETS cleanup program well in excess of $30 million for the potential cost of off-site transportation and treatment of radioactive liquid waste. (authors)

  11. Tensor to scalar ratio and large scale power suppression from pre-slow roll initial conditions

    SciTech Connect (OSTI)

    Lello, Louis; Boyanovsky, Daniel, E-mail: lal81@pitt.edu, E-mail: boyan@pitt.edu [Department of Physics and Astronomy, University of Pittsburgh, 3941 O'Hara St, Pittsburgh, PA 15260 (United States)

    2014-05-01

    We study the corrections to the power spectra of curvature and tensor perturbations and the tensor-to-scalar ratio r in single field slow roll inflation with standard kinetic term due to initial conditions imprinted by a ''fast-roll'' stage prior to slow roll. For a wide range of initial inflaton kinetic energy, this stage lasts only a few e-folds and merges smoothly with slow-roll thereby leading to non-Bunch-Davies initial conditions for modes that exit the Hubble radius during slow roll. We describe a program that yields the dynamics in the fast-roll stage while matching to the slow roll stage in a manner that is independent of the inflationary potentials. Corrections to the power spectra are encoded in a ''transfer function'' for initial conditions T{sub ?}(k), P{sub ?}(k) = P{sup BD}{sub ?}(k)T{sub ?}(k), implying a modification of the ''consistency condition'' for the tensor to scalar ratio at a pivot scale k{sub 0}: r(k{sub 0}) = ?8n{sub T}(k{sub 0})[T{sub T}(k{sub 0})/T{sub R}(k{sub 0})]. We obtain T{sub ?}(k) to leading order in a Born approximation valid for modes of observational relevance today. A fit yields T{sub ?}(k) = 1+A{sub ?}k{sup ?p}cos [2??k/H{sub sr}+?{sub ?}], with 1.5?suppression of the quadrupole and oscillatory features in both P{sub R}(k) and r(k{sub 0}) with a period of the order of the Hubble scale during slow roll inflation. The results are quite general and independent of the specific inflationary potentials, depending solely on the ratio of kinetic to potential energy ? and the slow roll parameters ?{sub V}, ?{sub V} to leading order in slow roll. For a wide range of ? and the values of ?{sub V};?{sub V} corresponding to the upper bounds from Planck, we find that the low quadrupole is consistent with the results from Planck, and

  12. Self-Assembled Monolayers of n-Alkanethiols Suppress Hydrogen Evolution and Increase the Efficiency of Rechargeable Iron Battery Electrodes

    SciTech Connect (OSTI)

    Malkhandi, S; Yang, B; Manohar, AK; Prakash, GKS; Narayanan, SR

    2013-01-09

    Iron-based rechargeable batteries, because of their low cost, eco-friendliness, and durability, are extremely attractive for large-scale energy storage. A principal challenge in the deployment of these batteries is their relatively low electrical efficiency. The low efficiency is due to parasitic hydrogen evolution that occurs on the iron electrode during charging and idle stand. In this study, we demonstrate for the first time that linear alkanethiols are very effective in suppressing hydrogen evolution on alkaline iron battery electrodes. The alkanethiols form self-assembled monolayers on the iron electrodes. The degree of suppression of hydrogen evolution by the alkanethiols was found to be greater than 90%, and the effectiveness of the alkanethiol increased with the chain length. Through steady-state potentiostatic polarization studies and impedance measurements on high-purity iron disk electrodes, we show that the self-assembly of alkanethiols suppressed the parasitic reaction by reducing the interfacial area available for the electrochemical reaction. We have modeled the effect of chain length of the alkanethiol on the surface coverage, charge-transfer resistance, and double-layer capacitance of the interface using a simple model that also yields a value for the interchain interaction energy. We have verified the improvement in charging efficiency resulting from the use of the alkanethiols in practical rechargeable iron battery electrodes. The results of battery tests indicate that alkanethiols yield among the highest faradaic efficiencies reported for the rechargeable iron electrodes, enabling the prospect of a large-scale energy storage solution based on low-cost iron-based rechargeable batteries.

  13. THE SUPPRESSION OF STAR FORMATION AND THE EFFECT OF THE GALAXY ENVIRONMENT IN LOW-REDSHIFT GALAXY GROUPS

    SciTech Connect (OSTI)

    Rasmussen, Jesper; Mulchaey, John S.; Bai, Lei; Ponman, Trevor J.; Raychaudhury, Somak; Dariush, Ali

    2012-10-01

    Understanding the interaction between galaxies and their surroundings is central to building a coherent picture of galaxy evolution. Here we use Galaxy Evolution Explorer imaging of a statistically representative sample of 23 galaxy groups at z Almost-Equal-To 0.06 to explore how local and global group environments affect the UV properties and dust-corrected star formation rates (SFRs) of their member galaxies. The data provide SFRs out to beyond 2R{sub 200} in all groups, down to a completeness limit and limiting galaxy stellar mass of 0.06 M{sub Sun} yr{sup -1} and 1 Multiplication-Sign 10{sup 8} M{sub Sun }, respectively. At fixed galaxy stellar mass, we find that the fraction of star-forming group members is suppressed relative to the field out to an average radius of R Almost-Equal-To 1.5 Mpc Almost-Equal-To 2R{sub 200}, mirroring results for massive clusters. For the first time, we also report a similar suppression of the specific SFR within such galaxies, on average by 40% relative to the field, thus directly revealing the impact of the group environment in quenching star formation within infalling galaxies. At fixed galaxy density and stellar mass, this suppression is stronger in more massive groups, implying that both local and global group environments play a role in quenching. The results favor an average quenching timescale of {approx}> 2 Gyr and strongly suggest that a combination of tidal interactions and starvation is responsible. Despite their past and ongoing quenching, galaxy groups with more than four members still account for at least {approx}25% of the total UV output in the nearby universe.

  14. Ginsenoside Rg3 regulates S-nitrosylation of the NLRP3 inflammasome via suppression of iNOS

    SciTech Connect (OSTI)

    Yoon, Sung-Jin; Park, Jun-Young; Choi, Song; Lee, Jin-Bong; Jung, Haiyoung; Kim, Tae-Don; Yoon, Suk Ran; Choi, Inpyo; Shim, Sungbo; Park, Young-Jun

    2015-08-07

    Ginsenoside Rg3, a specific biological effector, is well-known as a major bioactive ingredient of Panax ginseng. However, its role in the inflammasome activation process remains unclear. In this report, we demonstrate that ginsenosides 20(R)-Rg3 and 20(S)-Rg3 are capable of suppressing both lethal endotoxic shock and the S-nitrosylation of the NLRP3 inflammasome by inhibiting nitric oxide (NO) production through the regulation of inducible nitric oxide synthase (iNOS) expression. In response to lipopolysaccharide (LPS), the reducing effect of 20(S)-Rg3 and 20(R)-Rg3 on nitric oxide led to an increase in the survival time of mice after lethal endotoxin-induced shock, and excess levels of NO inhibited IL-1β production via the S-nitrosylation of the NLRP3 inflammasome. In addition, ginsenosides 20(R)-Rg3 and 20(S)-Rg3 had suppressive effects on the LPS- or UV-irradiation-induced reactive oxygen species (ROS) levels in macrophage and HaCaT cells and thereby prevented apoptosis of spleen cells in mice. Altogether, these results demonstrate that ginsenoside 20(R)-Rg3 and 20(S)-Rg3, a naturally occurring compound, might act as a dual therapeutic regulator for the treatment of inflammatory and oxidative stress-related diseases. - Highlights: • Ginsenosides Rg3 inhibits NO production through the regulation of iNOS expression. • Ginsenosides Rg3 inhibits the S-nitrosylation of the NLRP3 inflammasome. • Ginsenosides Rg3 suppress on the LPS- or UV-irradiation-induced ROS levels in cells.

  15. Suppression of the thermal hysteresis in magnetocaloric MnAs thin film by highly charged ion bombardment

    SciTech Connect (OSTI)

    Trassinelli, M. Marangolo, M.; Eddrief, M.; Etgens, V. H.; Gafton, V.; Hidki, S.; Lacaze, E.; Lamour, E.; Prigent, C.; Rozet, J.-P.; Steydli, S.; Zheng, Y.; Vernhet, D.

    2014-02-24

    We present the investigation on the modifications of structural and magnetic properties of MnAs thin film epitaxially grown on GaAs induced by slow highly charged ions bombardment under well-controlled conditions. The ion-induced defects facilitate the nucleation of one phase with respect to the other in the first-order magneto-structural MnAs transition, with a consequent suppression of thermal hysteresis without any significant perturbation on the other structural and magnetic properties. In particular, the irradiated film keeps the giant magnetocaloric effect at room temperature opening new perspective on magnetic refrigeration technology for everyday use.

  16. Histone deacetylase inhibitor valproic acid promotes the induction of pluripotency in mouse fibroblasts by suppressing reprogramming-induced senescence stress

    SciTech Connect (OSTI)

    Zhai, Yingying; Chen, Xi; Yu, Dehai; Li, Tao; Cui, Jiuwei; Wang, Guanjun; Hu, Ji-Fan; Li, Wei

    2015-09-10

    Histone deacetylase inhibitor valproic acid (VPA) has been used to increase the reprogramming efficiency of induced pluripotent stem cell (iPSC) from somatic cells, yet the specific molecular mechanisms underlying this effect is unknown. Here, we demonstrate that reprogramming with lentiviruses carrying the iPSC-inducing factors (Oct4-Sox2-Klf4-cMyc, OSKM) caused senescence in mouse fibroblasts, establishing a stress barrier for cell reprogramming. Administration of VPA protected cells from reprogramming-induced senescent stress. Using an in vitro pre-mature senescence model, we found that VPA treatment increased cell proliferation and inhibited apoptosis through the suppression of the p16/p21 pathway. In addition, VPA also inhibited the G2/M phase blockage derived from the senescence stress. These findings highlight the role of VPA in breaking the cell senescence barrier required for the induction of pluripotency. - Highlights: • Histone deacetylase inhibitor valproic acid enhances iPSC induction. • Valproic acid suppresses reprogramming-induced senescence stress. • Valproic acid downregulates the p16/p21 pathway in reprogramming. • This study demonstrates a new mechanistic role of valproic acid in enhancing reprogramming.

  17. Alloy Engineering of Defect Properties in Semiconductors: Suppression of Deep Levels in 2D Transition-metal Dichalcogenides

    SciTech Connect (OSTI)

    Huang, Bing; Yoon, Mina; Sumpter, Bobby G; Wei, Su-Huai; Liu, Feng

    2015-09-18

    Developing practical approaches to effectively reduce the deep defect levels in semiconductors is critical for their use in electronic and optoelectronic devices, but this is still a very challenging task. In this Letter, we propose that specific alloying can provide an effective means to suppress the deep defect levels in semiconductors while maintaining their basic electronic properties. Specifically, we demonstrate that for such 2D transition-metal dichalcogenides as MoSe2 and WSe2, in which the most abundant defects that can induce deep levels are anion vacancies, the deep levels can be effectively suppressed in Mo1-xWxSe2 alloys at low W concentrations. This surprising phenomenon is associated with the fact that the global alloy concentration can substantially tune the band edge energies, whereas the preferred locations of Se vacancies around W atoms control the defect level locally. Our findings illustrate a new concept of alloy engineering and provide a promising approach to control the defect properties of semiconductors.

  18. Piperlongumine selectively suppresses ABC-DLBCL through inhibition of NF-κB p65 subunit nuclear import

    SciTech Connect (OSTI)

    Niu, Mingshan; Shen, Yangling; Xu, Xiaoyu; Yao, Yao; Fu, Chunling; Yan, Zhiling; Wu, Qingyun; Cao, Jiang; Sang, Wei; Zeng, Lingyu; Li, Zhenyu; Liu, Xuejiao; and others

    2015-07-10

    Constitutive NF-κB activation is required for survival of activated B cell-like subtype of diffuse large B cell lymphoma (ABC-DLBCL). However, current NF-κB targeting strategies lack cancer cell specificity. Here, we identified a novel inhibitor, piperlongumine, features direct binding to NF-κB p65 subunit and suppression of p65 nuclear import. This was accompanied by NF-κB reporter activity suppression and NF-κB target gene downregulation. Moreover, mutation of Cys{sup 38} to Ser in p65 abolished this effect of piperlongumine on inhibition of p65 nuclear import. Furthermore, we show that piperlongumine selectively inhibited proliferation and induced apoptosis of ABC-DLBCL cells. Most notably, it has been reported that piperlongumine did not affect normal cells even at high doses and was nontoxic to animals. Hence, our current study provides new insight into piperlongumine's mechanism of action and novel approach to ABC-DLBCL target therapy. - Highlights: • Current NF-κB targeting strategies lack cancer cell specificity. • Piperlongumine inhibits NF-κB p65 subunit nuclear import via directly binding to p65. • Piperlongumine selectively inhibits proliferation of ABC-DLBCL cells. • This study provides a novel approach to ABC-DLBCL target therapy.

  19. Alloy Engineering of Defect Properties in Semiconductors: Suppression of Deep Levels in 2D Transition-metal Dichalcogenides

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

    Huang, Bing; Yoon, Mina; Sumpter, Bobby G; Wei, Su-Huai; Liu, Feng

    2015-09-18

    Developing practical approaches to effectively reduce the deep defect levels in semiconductors is critical for their use in electronic and optoelectronic devices, but this is still a very challenging task. In this Letter, we propose that specific alloying can provide an effective means to suppress the deep defect levels in semiconductors while maintaining their basic electronic properties. Specifically, we demonstrate that for such 2D transition-metal dichalcogenides as MoSe2 and WSe2, in which the most abundant defects that can induce deep levels are anion vacancies, the deep levels can be effectively suppressed in Mo1-xWxSe2 alloys at low W concentrations. This surprisingmore » phenomenon is associated with the fact that the global alloy concentration can substantially tune the band edge energies, whereas the preferred locations of Se vacancies around W atoms control the defect level locally. Our findings illustrate a new concept of alloy engineering and provide a promising approach to control the defect properties of semiconductors.« less

  20. Resolved H I imaging of a population of massive H I-rich galaxies with suppressed star formation

    SciTech Connect (OSTI)

    Lemonias, Jenna J.; Schiminovich, David; Catinella, Barbara; Heckman, Timothy M.; Moran, Sean M.

    2014-07-20

    Despite the existence of well-defined relationships between cold gas and star formation, there is evidence that some galaxies contain large amounts of H I that do not form stars efficiently. By systematically assessing the link between H I and star formation within a sample of galaxies with extremely high H I masses (log M{sub H{sub I}}/M{sub ?} > 10), we uncover a population of galaxies with an unexpected combination of high H I masses and low specific star formation rates that exists primarily at stellar masses greater than log M{sub *}/M{sub ?} ? 10.5. We obtained H I maps of 20 galaxies in this population to understand the distribution of the H I and the physical conditions in the galaxies that could be suppressing star formation in the presence of large quantities of H I. We find that all of the galaxies we observed have low H I surface densities in the range in which inefficient star formation is common. The low H I surface densities are likely the main cause of the low specific star formation rates, but there is also some evidence that active galactic nuclei or bulges contribute to the suppression of star formation. The sample's agreement with the global star formation law highlights its usefulness as a tool for understanding galaxies that do not always follow expected relationships.

  1. A Search for Direct CP Violation in Two-Body Cabibbo-Suppressed Decays of Neutral Charmed Mesons

    SciTech Connect (OSTI)

    Flacco, Christian Julienne

    2007-11-12

    Presented are the results of a search for direct CP violation in Cabibbo-suppressed decays of D{sup 0} to two charged daughters. The analysis described was performed on {approx}230 fb{sup -1} of the BABAR data sample, recorded at the Stanford Linear Accelerator Center and using the PEP-II electron storage rings. We measure CP asymmetries for decay to the KK and {pi}{pi} final states, as well as for the branching ratio, and develop a new technique for tagging-efficiency correction using the Cabibbo-favored K{pi} final state. We find some evidence for CP violation in decays to the KK final state and results that suggest CP violation in the {pi}{pi} final state as well.

  2. Suppression of somatic expansion delays the onset of pathophysiology in a mouse model of Huntington’s Disease

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

    Budworth, Helen; Harris, Faye R.; Williams, Paul; Lee, Do Yup; Holt, Amy; Pahnke, Jens; Szczesny, Bartosz; Acevedo-Torres, Karina; Ayala-Peña, Sylvette; McMurray, Cynthia T.; et al

    2015-08-06

    Huntington’s Disease (HD) is caused by inheritance of a single disease-length allele harboring an expanded CAG repeat, which continues to expand in somatic tissues with age. The inherited disease allele expresses a toxic protein, and whether further somatic expansion adds to toxicity is unknown. We have created an HD mouse model that resolves the effects of the inherited and somatic expansions. We show here that suppressing somatic expansion substantially delays the onset of disease in littermates that inherit the same disease-length allele. Furthermore, a pharmacological inhibitor, XJB-5-131, inhibits the lengthening of the repeat tracks, and correlates with rescue of motormore » decline in these animals. The results provide evidence that pharmacological approaches to offset disease progression are possible.« less

  3. Suppression of somatic expansion delays the onset of pathophysiology in a mouse model of Huntington’s Disease

    SciTech Connect (OSTI)

    Budworth, Helen; Harris, Faye R.; Williams, Paul; Lee, Do Yup; Holt, Amy; Pahnke, Jens; Szczesny, Bartosz; Acevedo-Torres, Karina; Ayala-Peña, Sylvette; McMurray, Cynthia T.; McKinnon, Peter

    2015-08-06

    Huntington’s Disease (HD) is caused by inheritance of a single disease-length allele harboring an expanded CAG repeat, which continues to expand in somatic tissues with age. The inherited disease allele expresses a toxic protein, and whether further somatic expansion adds to toxicity is unknown. We have created an HD mouse model that resolves the effects of the inherited and somatic expansions. We show here that suppressing somatic expansion substantially delays the onset of disease in littermates that inherit the same disease-length allele. Furthermore, a pharmacological inhibitor, XJB-5-131, inhibits the lengthening of the repeat tracks, and correlates with rescue of motor decline in these animals. The results provide evidence that pharmacological approaches to offset disease progression are possible.

  4. Blinking suppression of CdTe quantum dots on epitaxial graphene and the analysis with Marcus electron transfer

    SciTech Connect (OSTI)

    Hirose, Takuya; Tamai, Naoto, E-mail: tamai@kwansei.ac.jp [Department of Chemistry, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan); Kutsuma, Yasunori; Kurita, Atsusi; Kaneko, Tadaaki [Department of Physics, School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo 669-1337 (Japan)

    2014-08-25

    We have prepared epitaxial graphene by a Si sublimation method from 4H-SiC. Single-particle spectroscopy of CdTe quantum dots (QDs) on epitaxial graphene covered with polyvinylpyrrolidone (PVP) or polyethylene glycol (PEG) showed the suppression of luminescence blinking and ?10 times decreased luminescence intensity as compared with those on a glass. The electronic coupling constant, H{sub 01}, between CdTe QDs and graphene was calculated to be (3.3??0.4)??10{sup 2?}cm{sup ?1} in PVP and (3.7??0.8)??10{sup 2?}cm{sup ?1} in PEG based on Marcus theory of electron transfer and Tang-Marcus model of blinking with statistical distribution.

  5. Suppression of Upsilon production in d + Au and Au + Au collisions at root s(NN) = 200 GeV (vol 735, pg 127, 2014)

    SciTech Connect (OSTI)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Gliske, S.; Krueger, K.; Spinka, H. M.; Underwood, D.G.

    2014-07-30

    We report measurements of ? meson production in p + p, d +Au, and Au+Aucollisions using the STAR detector at RHIC. We compare the ? yield to the measured cross section in p + p collisions in order to quantify any modifications of the yield in cold nuclear matter using d +Au data and in hot nuclear matter using Au+Au data separated into three centrality classes. Our p +p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for ? (1S + 2S + 3S) in the rapidity range |y| < 1 in d + Aucollisions of RdAu = 0.79 0.24(stat.) 0.03(syst.) 0.10(p + p syst.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au + Au collisions, we measure a nuclear modification factor of R AA = 0.49 0.1(stat.) 0.02(syst.) 0.06(p + p syst.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state ? mesons in Au + Aucollisions. The additional suppression in Au + Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined QuarkGluon Plasma. However, understanding the suppression seen in d + Au is still needed before any definitive statements about the nature of the suppression in Au + Au can be made.

  6. Preferential cytotoxicity of bortezomib toward highly malignant human liposarcoma cells via suppression of MDR1 expression and function

    SciTech Connect (OSTI)

    Hu, Yamei; Wang, Lingxian; Wang, Lu; Wu, Xuefeng; Wu, Xudong; Gu, Yanhong; Shu, Yongqian; Sun, Yang; Shen, Yan; Xu, Qiang

    2015-02-15

    Liposarcoma is the most common soft tissue sarcoma with a high risk of relapse. Few therapeutic options are available for the aggressive local or metastatic disease. Here, we report that the clinically used proteasome inhibitor bortezomib exhibits significantly stronger cytotoxicity toward highly malignant human liposarcoma SW872-S cells compared with its parental SW872 cells, which is accompanied by enhanced activation of apoptotic signaling both in vitro and in vivo. Treatment of cells with Jun-N-terminal kinase (JNK) inhibitor SP60015 or the translation inhibitor cycloheximide ameliorated this enhanced apoptosis. Bortezomib inhibited MDR1 expression and function more effectively in SW872-S cells than in SW872 cells, indicating that the increased cytotoxicity relies on the degree of proteasome inhibition. Furthermore, the pharmacological or genetic inhibition of sarco/endoplasmic reticulum calcium-ATPase (SERCA) 2, which is highly expressed in SW872-S cells, resulted in partial reversal of cell growth inhibition and increase of MDR1 expression in bortezomib-treated SW872-S cells. These results show that bortezomib exhibits preferential cytotoxicity toward SW872-S cells possibly via highly expressed SERCA2-associated MDR1 suppression and suggest that bortezomib may serve as a potent agent for treating advanced liposarcoma. - Highlights: • We compare the cytotoxicity of different drugs between SW872-S and SW872 cells. • Highly malignant liposarcoma cells SW872-S show hypersensitivity to bortezomib. • Apoptotic signaling is robustly enhanced in bortezomib-treated SW872-S cells. • Bortezomib has strong suppression on MDR1 expression and function in SW872-S cells. • Inhibition of SERCA2 protects SW872-S cells from bortezomib.

  7. WIND-DRIVEN ACCRETION IN PROTOPLANETARY DISKS. I. SUPPRESSION OF THE MAGNETOROTATIONAL INSTABILITY AND LAUNCHING OF THE MAGNETOCENTRIFUGAL WIND

    SciTech Connect (OSTI)

    Bai Xuening; Stone, James M., E-mail: xbai@cfa.harvard.edu [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States)

    2013-05-20

    We perform local, vertically stratified shearing-box MHD simulations of protoplanetary disks (PPDs) at a fiducial radius of 1 AU that take into account the effects of both Ohmic resistivity and ambipolar diffusion (AD). The magnetic diffusion coefficients are evaluated self-consistently from a look-up table based on equilibrium chemistry. We first show that the inclusion of AD dramatically changes the conventional picture of layered accretion. Without net vertical magnetic field, the system evolves into a toroidal field dominated configuration with extremely weak turbulence in the far-UV ionization layer that is far too inefficient to drive rapid accretion. In the presence of a weak net vertical field (plasma {beta} {approx} 10{sup 5} at midplane), we find that the magnetorotational instability (MRI) is completely suppressed, resulting in a fully laminar flow throughout the vertical extent of the disk. A strong magnetocentrifugal wind is launched that efficiently carries away disk angular momentum and easily accounts for the observed accretion rate in PPDs. Moreover, under a physical disk wind geometry, all the accretion flow proceeds through a strong current layer with a thickness of {approx}0.3H that is offset from disk midplane with radial velocity of up to 0.4 times the sound speed. Both Ohmic resistivity and AD are essential for the suppression of the MRI and wind launching. The efficiency of wind transport increases with increasing net vertical magnetic flux and the penetration depth of the FUV ionization. Our laminar wind solution has important implications on planet formation and global evolution of PPDs.

  8. The aryl hydrocarbon receptor suppresses osteoblast proliferation and differentiation through the activation of the ERK signaling pathway

    SciTech Connect (OSTI)

    Yu, Haitao; Du, Yuxuan; Zhang, Xulong; Sun, Ying; Li, Shentao; Dou, Yunpeng; Li, Zhanguo; Yuan, Huihui; Zhao, Wenming

    2014-11-01

    Ahr activation is known to be associated with synovitis and exacerbated rheumatoid arthritis (RA), but its contributions to bone loss have not been completely elucidated. Osteoblast proliferation and differentiation are abnormal at the erosion site in RA. Here, we reported that the expression of Ahr was increased in the hind paws' bone upon collagen-induced arthritis (CIA) in mice, and the levels of Ahr were negatively correlated with bone mineral density (BMD). In addition, immunofluorescent staining showed that the high expression of Ahr was mainly localized in osteoblasts from the CIA mice compared to normal controls. Moreover, the luciferase intensity of Ahr in the nucleus increased by 12.5% in CIA osteoblasts compared to that in normal controls. In addition, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) activation of the Ahr inhibited pre-osteoblast MC3T3-E1 cellular proliferation and differentiation in a dose-dependent manner. Interestingly, the levels of alkaline phosphatase (ALP) mRNA expression in the osteoblasts of CIA mice were reduced compared to normal controls. In contrast, decreased ALP expression by activated Ahr was completely reversed after pretreatment with an Ahr inhibitor (CH-223191) in MC3T3-E1 cell lines and primary osteoblasts on day 5. Our data further showed that activation of Ahr promoted the phosphorylation of ERK after 5 days. Moreover, Ahr-dependent activation of the ERK signaling pathway decreased the levels of proliferation cells and inhibited ALP activity in MC3T3-E1 cells. These results demonstrated that the high expression of Ahr may suppress osteoblast proliferation and differentiation through activation of the ERK signaling pathway, further enabling bone erosion in CIA mice. - Highlights: • The upregulation of Ahr was localized in osteoblasts of CIA mice. • The overexpression of Ahr suppressed osteoblast development. • The Ahr activated ERK signaling pathway to exacerbate bone erosion.

  9. Parton intrinsic motion: Suppression of the Collins mechanism for transverse single spin asymmetries in p{sup {up_arrow}}p{yields}{pi}X

    SciTech Connect (OSTI)

    Anselmino, M.; Boglione, M.; D'Alesio, U.; Murgia, F.; Leader, E.

    2005-01-01

    We consider a general formalism to compute inclusive polarized and unpolarized cross sections within pQCD and the factorization scheme, taking into account parton intrinsic motion in distribution and fragmentation functions, as well as in the elementary dynamics. Surprisingly, the intrinsic partonic motion, with all the correct azimuthal angular dependences, produces a strong suppression of the transverse single spin asymmetry arising from the Collins mechanism. As a consequence, and in contradiction with earlier claims, the Collins mechanism is unable to explain the large asymmetries found in p{sup {up_arrow}}p{yields}{pi}X at moderate to large Feynman x{sub F}. The Sivers effect is not suppressed.

  10. Electrical current suppression in Pd-doped vanadium pentoxide nanowires caused by reduction in PdO due to hydrogen exposure

    SciTech Connect (OSTI)

    Kim, Byung Hoon; Oh, Soon-Young; Yu, Han Young; Yun, Yong Ju; Kim, Yark Yeon; Hong, Won G.; Jeong, Hu Young; Lee, Jeong Yong; Kim, Hae Jin

    2010-04-19

    Pd nanoparticle-doped vanadium pentoxide nanowires (Pd-VONs) were synthesized. Electrical current suppression was observed when the Pd-VON was exposed to hydrogen gas, which cannot be explained by the work function changes mentioned in previous report such as Pd-doped carbon nanotubes and SnO{sub 2} nanowires. Using the x-ray photoelectron spectroscopy, we found that the reduction in PdO due to hydrogen exposure plays an important role in the current suppression of the Pd-VON.

  11. Measurement of Branching Ratios for Non-leptonic Cabibbo-suppressed Decays of the Charmed-Strange Baryon Xic+

    SciTech Connect (OSTI)

    Vazquez Jauregui, Eric; /San Luis Potosi U.

    2008-08-01

    We studied several {Xi}{sub c}{sup +} decay modes, most of them with a hyperon in the final state, and determined their branching ratios. The data used in this analysis come from the fixed target experiment SELEX, a multi-stage spectrometer with high acceptance for forward interactions, that took data during 1996 and 1997 at Fermilab with 600 GeV=c (mainly {Sigma}{sup -}, {pi}{sup -}) and 540 GeV/c (mainly p) beams incident on copper and carbon targets. The thesis mainly details the first observation of two Cabibbo-suppressed decay modes, {Xi}{sub c}{sup +} {yields} {Sigma}{sup +}{pi}{sup -}{pi}{sup +} and {Xi}{sub c}{sup +} {yields} {Sigma}{sup -}{pi}{sup +}{pi}{sup +}. The branching ratios of the decays relative to the Cabibbo-favored {Xi}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup +} are measured to be: {Lambda}({Xi}{sub c}{sup +} {yields} {Sigma}{sup -}{pi}{sup +}{pi}{sup +})/{Lambda}({Xi}{sub c}{sup +} {yields} {Xi}{sup -}{pi}{sup +}{pi}{sup +}) = 0.184 {+-} 0.086. Systematic studies have been performed in order to check the stability of the measurements varying all cuts used in the selection of events over a wide interval and we do not observe evidence of any trend, so the systematic error is negligible in the final results because the quadrature sum of the total error is not affected. The branching ratios for the same decay modes of the {Lambda}{sub c}{sup +} are measured to check the methodology of the analysis. The branching ratio of the decay mode {Lambda}{sub c}{sup +} {yields} {Sigma}{sup +}{pi}{sup -}{pi}{sup +} is measured relative to {Lambda}{sub c}{sup +} {yields} pK{sup -} {pi}{sup +}, while the one of the decay mode {Lambda}{sub c}{sup +} {yields} {Sigma}{sup -}{pi}{sup +}{pi}{sup +} is relative to {Lambda}{sub c}{sup +} {yields} {Sigma}{sup +}{pi}{sup -}{pi}{sup +}, as they have been reported earlier. The results for the control modes are: {Gamma}({Lambda}{sub c}{sup +} {yields} {Sigma}{sup +}{pi}{sup -}{pi}{sup +})/{Gamma

  12. All-or-none suppression of B cell terminal differentiation by environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin

    SciTech Connect (OSTI)

    Zhang, Qiang; Kline, Douglas E.; Bhattacharya, Sudin; Crawford, Robert B.; Conolly, Rory B.; Thomas, Russell S.; Andersen, Melvin E.; Kaminski, Norbert E.

    2013-04-01

    Many environmental contaminants can disrupt the adaptive immune response. Exposure to the ubiquitous aryl hydrocarbon receptor (AhR) ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and other agonists suppresses the antibody response. The underlying pathway mechanism by which TCDD alters B cell function is not well understood. The present study investigated the mechanism of AhR-mediated pathways and mode of suppression by which TCDD perturbs terminal differentiation of B cells to plasma cells and thereby impairs antibody production. An integrated approach combining computational pathway modeling and in vitro assays with primary mouse B cells activated by lipopolysaccharide was employed. We demonstrated that suppression of the IgM response by TCDD occurs in an all-or-none (binary) rather than graded mode: i.e., it reduces the number of IgM-secreting cells in a concentration-dependent manner without affecting the IgM content in individual plasma cells. The mathematical model of the gene regulatory circuit underpinning B cell differentiation revealed that two previously identified AhR-regulated pathways, inhibition of signaling protein AP-1 and activation of transcription factor Bach2, could account for the all-or-none mode of suppression. Both pathways disrupt the operation of a bistable-switch circuit that contains transcription factors Bcl6, Prdm1, Pax5, and Bach2 and regulates B cell fate. The model further predicted that by transcriptionally activating Bach2, TCDD might delay B cell differentiation and increase the likelihood of isotype switching, thereby altering the antibody repertoire. In conclusion, the present study revealed the mode and specific pathway mechanisms by which the environmental immunosuppressant TCDD suppresses B cell differentiation. - Highlights: ? TCDD suppresses B cell differentiation stimulated by LPS in an all-or-none mode. ? TCDD reduces the fraction of IgM-secreting cells, not the IgM level in those cells. ? A mathematical model

  13. Strong far-infrared cooling lines, peculiar CO kinematics, and possible star-formation suppression in Hickson compact group 57

    SciTech Connect (OSTI)

    Alatalo, K.; Appleton, P. N.; Ogle, P. M.; Rich, J. A.; Xu, C. K.; Lisenfeld, U.; Bitsakis, T.; Guillard, P.; Charmandaris, V.; Cluver, M.; Jarrett, T.; Dopita, M. A.; Kewley, L. J.; Freeland, E.; Rasmussen, J.; Verdes-Montenegro, L.

    2014-11-10

    We present [C II] and [O I] observations from Herschel and CO(1-0) maps from the Combined Array for Research in Millimeter Astronomy (CARMA) of the Hickson compact group HCG 57, focusing on the galaxies HCG 57a and HCG 57d. HCG 57a has been previously shown to contain enhanced quantities of warm molecular hydrogen consistent with shock or turbulent heating. Our observations show that HCG 57d has strong [C II] emission compared to L {sub FIR} and weak CO(1-0), while in HCG 57a, both the [C II] and CO(1-0) are strong. HCG 57a lies at the upper end of the normal distribution of the [C II]/CO and [C II]/FIR ratios, and its far-infrared (FIR) cooling supports a low-density, warm, diffuse gas that falls close to the boundary of acceptable models of a photon-dominated region. However, the power radiated in the [C II] and warm H{sub 2} emissions have similar magnitudes, as seen in other shock-dominated systems and predicted by recent models. We suggest that shock heating of the [C II] is a viable alternative to photoelectric heating in violently disturbed, diffuse gas. The existence of shocks is also consistent with the peculiar CO kinematics in the galaxy, indicating that highly noncircular motions are present. These kinematically disturbed CO regions also show evidence of suppressed star formation, falling a factor of 10-30 below normal galaxies on the Kennicutt-Schmidt relation. We suggest that the peculiar properties of both galaxies are consistent with a highly dissipative, off-center collisional encounter between HCG 57d and 57a, creating ring-like morphologies in both systems. Highly dissipative gas-on-gas collisions may be more common in dense groups because of the likelihood of repeated multiple encounters. The possibility of shock-induced star-formation suppression may explain why a subset of these HCG galaxies has been found previously to fall in the mid-infrared green valley.

  14. Proton pump inhibitors suppress iNOS-dependent DNA damage in Barrett's esophagus by increasing Mn-SOD expression

    SciTech Connect (OSTI)

    Thanan, Raynoo; Ma, Ning; Iijima, Katsunori; Abe, Yasuhiko; Koike, Tomoyuki; Shimosegawa, Tooru; Pinlaor, Somchai; Hiraku, Yusuke; Oikawa, Shinji; Murata, Mariko; Kawanishi, Shosuke

    2012-05-04

    Highlights: Black-Right-Pointing-Pointer Inflammation by Barrett's esophagus (BE) is a risk factor of its adenocarcinoma (BEA). Black-Right-Pointing-Pointer 8-Nitroguanine and 8-oxodG are inflammation-related DNA lesions. Black-Right-Pointing-Pointer DNA lesions and iNOS expression were higher in the order, BEA > BE > normal tissues. Black-Right-Pointing-Pointer Proton pump inhibitors suppress DNA damage by increasing Mn-SOD via Nrf2 activation. Black-Right-Pointing-Pointer DNA lesions can be useful biomarkers to predict risk of BEA in BE patients. -- Abstract: Barrett's esophagus (BE), an inflammatory disease, is a risk factor for Barrett's esophageal adenocarcinoma (BEA). Treatment of BE patients with proton pump inhibitors (PPIs) is expected to reduce the risk of BEA. We performed an immunohistochemical study to examine the formation of nitrative and oxidative DNA lesions, 8-nitroguanine and 8-oxo-7,8-dihydro-2 Prime -deoxygaunosine (8-oxodG), in normal esophageal, BE with pre- and post-treatment by PPIs and BEA tissues. We also observed the expression of an oxidant-generating enzyme (iNOS) and its transcription factor NF-{kappa}B, an antioxidant enzyme (Mn-SOD), its transcription factor (Nrf2) and an Nrf2 inhibitor (Keap1). The immunoreactivity of DNA lesions was significantly higher in the order of BEA > BE > normal tissues. iNOS expression was significantly higher in the order of BEA > BE > normal tissues, while Mn-SOD expression was significantly lower in the order of BEA < BE < normal tissues. Interestingly, Mn-SOD expression and the nuclear localization of Nrf2 were significantly increased, and the formation of DNA lesions was significantly decreased in BE tissues after PPIs treatment for 3-6 months. Keap1 and iNOS expression was not significantly changed by the PPIs treatment in BE tissues. These results indicate that 8-nitroguanine and 8-oxodG play a role in BE-derived BEA. Additionally, PPIs treatment may trigger the activation and nuclear translocation

  15. Modeled microgravity suppressed invasion and migration of human glioblastoma U87 cells through downregulating store-operated calcium entry

    SciTech Connect (OSTI)

    Shi, Zi-xuan; Rao, Wei; Wang, Huan; Wang, Nan-ding; Si, Jing-Wen; Zhao, Jiao; Li, Jun-chang; Wang, Zong-ren

    2015-02-13

    Glioblastoma is the most common brain tumor and is characterized with robust invasion and migration potential resulting in poor prognosis. Previous investigations have demonstrated that modeled microgravity (MMG) could decline the cell proliferation and attenuate the metastasis potential in several cell lines. In this study, we studied the effects of MMG on the invasion and migration potentials of glioblastoma in human glioblastoma U87 cells. We found that MMG stimulation significantly attenuated the invasion and migration potentials, decreased thapsigargin (TG) induced store-operated calcium entry (SOCE) and downregulated the expression of Orai1 in U87 cells. Inhibition of SOCE by 2-APB or stromal interaction molecule 1 (STIM1) downregulation both mimicked the effects of MMG on the invasion and migration potentials in U87 cells. Furthermore, upregulation of Orai1 significantly weakened the effects of MMG on the invasion and migration potentials in U87 cells. Therefore, these findings indicated that MMG stimulation inhibited the invasion and migration potentials of U87 cells by downregulating the expression of Orai1 and sequentially decreasing the SOCE, suggesting that MMG might be a new potential therapeutic strategy in glioblastoma treatment in the future. - Highlights: • Modeled microgravity (MMG) suppressed migration and invasion in U87 cells. • MMG downregulated the SOCE and the expression of Orai1. • SOCE inhibition mimicked the effects of MMG on migration and invasion potentials. • Restoration of SOCE diminished the effects of MMG on migration and invasion.

  16. Suppression of external quantum efficiency roll-off of nanopatterned organic-light emitting diodes at high current densities

    SciTech Connect (OSTI)

    Kuwae, Hiroyuki; Kasahara, Takashi; Nitta, Atsushi; Yoshida, Kou; Inoue, Munetomo; Matsushima, Toshinori; Adachi, Chihaya; Shoji, Shuichi; Mizuno, Jun

    2015-10-21

    We developed organic light-emitting diodes (OLEDs) with nanopatterned current flow regions using electron-beam lithography with the aim of suppressing singlet–polaron annihilation (SPA). Nanopatterns composed of lines and circles were used in the current flow regions of nano-line and nano-dot OLEDs, respectively. Excitons partially escape from the current flow regions where SPA takes place. As such, current densities where external quantum efficiencies were half of their initial values (J{sub 0}) increased as line width and circle diameter were decreased to close to the exciton diffusion length. Circles were more efficient at enhancing exciton escape and increasing J{sub 0} than lines. The J{sub 0} increase in the nano-dot OLEDs containing nanopatterned circles with a diameter of 50 nm was approximately 41-fold that of a conventional OLED with a current flow region of 4 mm{sup 2}. The dependence of J{sub 0} on the size and shape of the nanopatterns was well explained by an SPA model that considered exciton diffusion. Nanopatterning of OLEDs is a feasible method of obtaining large J{sub 0}.

  17. Triptolide inhibits TGF-β1-induced cell proliferation in rat airway smooth muscle cells by suppressing Smad signaling

    SciTech Connect (OSTI)

    Chen, Ming; Lv, Zhiqiang; Huang, Linjie; Zhang, Wei; Lin, Xiaoling; Shi, Jianting; Zhang, Wei; Liang, Ruiyun; Jiang, Shanping

    2015-02-15

    Background: We have reported that triptolide can inhibit airway remodeling in a murine model of asthma via TGF-β1/Smad signaling. In the present study, we aimed to investigate the effect of triptolide on airway smooth muscle cells (ASMCs) proliferation and the possible mechanism. Methods: Rat airway smooth muscle cells were cultured and made synchronized, then pretreated with different concentration of triptolide before stimulated by TGF-β1. Cell proliferation was evaluated by MTT assay. Flow cytometry was used to study the influence of triptolide on cell cycle and apoptosis. Signal proteins (Smad2, Smad3 and Smad7) were detected by western blotting analysis. Results: Triptolide significantly inhibited TGF-β1-induced ASMC proliferation (P<0.05). The cell cycle was blocked at G1/S-interphase by triptolide dose dependently. No pro-apoptotic effects were detected under the concentration of triptolide we used. Western blotting analysis showed TGF-β1 induced Smad2 and Smad3 phosphorylation was inhibited by triptolide pretreatment, and the level of Smad7 was increased by triptolide pretreatment. Conclusions: Triptolide may function as an inhibitor of asthma airway remodeling by suppressing ASMCs proliferation via negative regulation of Smad signaling pathway. - Highlights: • In this study, rat airway smooth muscle cells were cultured and made synchronized. • Triptolide inhibited TGF-β1-induced airway smooth muscle cells proliferation. • Triptolide inhibited ASMCs proliferation via negative regulation of Smad signaling pathway.

  18. SAR ambiguous range suppression.

    SciTech Connect (OSTI)

    Doerry, Armin Walter

    2006-09-01

    Pulsed Radar systems suffer range ambiguities, that is, echoes from pulses transmitted at different times arrive at the receiver simultaneously. Conventional mitigation techniques are not always adequate. However, pulse modulation schemes exist that allow separation of ambiguous ranges in Doppler space, allowing easy filtering of problematic ambiguous ranges.

  19. Fire suppressing apparatus

    DOE Patents [OSTI]

    Buttrey, Kenneth E.

    1982-11-02

    Apparatus for smothering a liquid sodium fire comprises a pan, a perforated cover on the pan, and tubes depending from the cover and providing communication between the interior of the pan and the ambient atmosphere through the perforations in the cover. Liquid caught in the pan rises above the lower ends of the tubes and thus serves as a barrier which limits the amount of air entering the pan.

  20. Trisomy of the Dscr1 gene suppresses early progression of pancreatic intraepithelial neoplasia driven by oncogenic Kras

    SciTech Connect (OSTI)

    Lee, Jang Choon; Shin, Jimin; Baek, Kwan-Hyuck

    2013-10-11

    Highlights: A single extra copy of Dscr1 restrains progression of PanIN-1A to PanIN-1B lesions. Dscr1 trisomy attenuates calcineurinNFAT pathway in neoplastic ductal epithelium. Dscr1 trisomy leads to upregulation of p15{sup INK4b} in neoplastic ductal epithelium. A single extra copy of Dscr1 reduces epithelial proliferation in early PanIN lesions. Dscr1 trisomy may protect Down syndrome individuals from pancreatic cancer. -- Abstract: Individuals with Down syndrome exhibit remarkably reduced incidence of most solid tumors including pancreatic cancer. Multiple mechanisms arising from the genetic complexity underlying Down syndrome has been suggested to contribute to such a broad cancer protection. In this study, utilizing a genetically engineered mouse model of pancreatic cancer, we demonstrate that trisomy of the Down syndrome critical region-1 (Dscr1), an endogenous calcineurin inhibitor localized on chromosome 21, suppresses the progression of pancreatic intraepithelial neoplasia-1A (PanIN-1A) to PanIN-1B lesions without affecting the initiation of PanIN lesions mediated by oncogenic Kras{sup G12D}. In addition, we show that Dscr1 trisomy attenuates nuclear localization of nuclear factor of activated T-cells (NFAT) accompanied by upregulation of the p15{sup Ink4b} tumor suppressor and reduction of cell proliferation in early PanIN lesions. Our data suggest that attenuation of calcineurinNFAT signaling in neoplastic pancreatic ductal epithelium by a single extra copy of Dscr1 is sufficient to inhibit the progression of early PanIN lesions driven by oncogenic Kras, and thus may be a potential mechanism underlying reduced incidence of pancreatic cancer in Down syndrome individuals.

  1. Overexpression of miR-206 suppresses glycolysis, proliferation and migration in breast cancer cells via PFKFB3 targeting

    SciTech Connect (OSTI)

    Ge, Xin; Lyu, Pengwei; Cao, Zhang; Li, Jingruo; Guo, Guangcheng; Xia, Wanjun; Gu, Yuanting

    2015-08-07

    miRNAs, sorting as non-coding RNAs, are differentially expressed in breast tumor and act as tumor promoters or suppressors. miR-206 could suppress the progression of breast cancer, the mechanism of which remains unclear. The study here was aimed to investigate the effect of miR-206 on human breast cancers. We found that miR-206 was down-regulated while one of its predicted targets, 6-Phosphofructo-2-kinase (PFKFB3) was up-regulated in human breast carcinomas. 17β-estradiol dose-dependently decreased miR-206 expression as well as enhanced PFKFB3 mRNA and protein expression in estrogen receptor α (ERα) positive breast cancer cells. Furthermore, we identified that miR-206 directly interacted with 3′-untranslated region (UTR) of PFKFB3 mRNA. miR-206 modulated PFKFB3 expression in MCF-7, T47D and SUM159 cells, which was influenced by 17β-estradiol depending on ERα expression. In addition, miR-206 overexpression impeded fructose-2,6-bisphosphate (F2,6BP) production, diminished lactate generation and reduced cell proliferation and migration in breast cancer cells. In conclusion, our study demonstrated that miR-206 regulated PFKFB3 expression in breast cancer cells, thereby stunting glycolysis, cell proliferation and migration. - Highlights: • miR-206 was down-regulated and PFKFB3 was up-regulated in human breast carcinomas. • 17β-estradiol regulated miR-206 and PFKFB3 expression in ERα+ cancer cells. • miR-206directly interacted with 3′-UTR of PFKFB3 mRNA. • miR-206 fructose-2,6-bisphosphate (F2,6BP) impeded production and lactate generation. • miR-206 reduced cell proliferation and migration in breast cancer cells.

  2. Suppression and nonlinear excitation of parasitic modes in second harmonic gyrotrons operating in a very high order mode

    SciTech Connect (OSTI)

    Nusinovich, Gregory S.; Pu, Ruifeng; Granatstein, Victor L.

    2015-07-06

    In recent years, there was an active development of high-power, sub-terahertz (sub-THz) gyrotrons for numerous applications. For example, a 0.67 THz gyrotron delivering more than 200 kW with about 20% efficiency was developed. This record high efficiency was achieved because the gyrotron operated in a high-order TE{sub 31,8}-mode with the power of ohmic losses less than 10% of the power of outgoing radiation. That gyrotron operated at the fundamental cyclotron resonance, and a high magnetic field of about 27 T was created by a pulse solenoid. For numerous applications, it is beneficial to use gyrotrons at cyclotron harmonics which can operate in available cryomagnets with fields not exceeding 15 T. However, typically, the gyrotron operation at harmonics faces severe competition from parasitic modes at the fundamental resonance. In the present paper, we consider a similar 0.67 THz gyrotron designed for operation in the same TE{sub 31,8}-mode, but at the second harmonic. We focus on two nonlinear effects typical for interaction between the fundamental and second harmonic modes, viz., the mode suppression and the nonlinear excitation of the mode at the fundamental harmonic by the second harmonic oscillations. Our study includes both the analytical theory and numerical simulations performed with the self-consistent code MAGY. The simulations show that stable second harmonic operation in the TE{sub 31,8} mode is possible with only modest sacrifice of efficiency and power.

  3. miR-214 promotes the proliferation and invasion of osteosarcoma cells through direct suppression of LZTS1

    SciTech Connect (OSTI)

    Xu, Zhengyu; Wang, Tao

    2014-06-27

    Highlights: • miR-214 is upregulated in human OS tissues and inversely correlated with LZTS1 expression. • miR-214 directly targets LZTS1 by binding to its 3′-UTR. • miR-214 promotes OS cell proliferation, invasion and tumor growth. • Overexpression of LZTS1 reverses miR-214-induced proliferation and invasion of OS cells. - Abstract: Previous studies have shown that miR-214 functions either as an oncogene or a tumor suppressor in various human cancer types. The role of this microRNA in osteosarcoma (OS) is presently unclear. Here, we demonstrated that miR-214 is frequently upregulated in OS specimens, compared with noncancerous bone tissues. Bioinformatics analysis further revealed leucine zipper, putative tumor suppressor 1 (LZTS1) as a potential target of miR-214. Expression patterns of miR-214 were inversely correlated with those of LZTS1 mRNA and protein in OS tissues. Data from reporter assays showed that miR-214 directly binds to the 3′-untranslated region (3′-UTR) of LZTS1 mRNA and suppresses expression at both transcriptional and translational levels. In functional assays, miR-214 promoted OS cell proliferation, invasion and tumor growth in nude mice, which could be reversed by overexpression of LZTS1. Taken together, our data provide compelling evidence that miR-214 functions as an onco-miRNA in OS, and its oncogenic effects are mediated chiefly through downregulation of LZTS1.

  4. MicroRNA-320a suppresses human colon cancer cell proliferation by directly targeting {beta}-catenin

    SciTech Connect (OSTI)

    Sun, Jian-Yong; State Key Laboratory of Cancer Biology, Xijing Hospital of Digestive Diseases, Fourth Military Medical University, 710032 Xi'an ; Huang, Yi; Li, Ji-Peng; Zhang, Xiang; Wang, Lei; Meng, Yan-Ling; Yan, Bo; Bian, Yong-Qian; Zhao, Jing; Wang, Wei-Zhong; and others

    2012-04-20

    Highlights: Black-Right-Pointing-Pointer miR-320a is downregulated in human colorectal carcinoma. Black-Right-Pointing-Pointer Overexpression of miR-320a inhibits colon cancer cell proliferation. Black-Right-Pointing-Pointer {beta}-Catenin is a direct target of miR-320a in colon cancer cells. Black-Right-Pointing-Pointer miR-320a expression inversely correlates with mRNA expression of {beta}-catenin's target genes in human colon carcinoma. -- Abstract: Recent profile studies of microRNA (miRNA) expression have documented a deregulation of miRNA (miR-320a) in human colorectal carcinoma. However, its expression pattern and underlying mechanisms in the development and progression of colorectal carcinoma has not been elucidated clearly. Here, we performed real-time PCR to examine the expression levels of miR-320a in colon cancer cell lines and tumor tissues. And then, we investigated its biological functions in colon cancer cells by a gain of functional strategy. Further more, by the combinational approaches of bioinformatics and experimental validation, we confirmed target associations of miR-320a in colorectal carcinoma. Our results showed that miR-320a was frequently downregulated in cancer cell lines and colon cancer tissues. And we demonstrated that miR-320a restoration inhibited colon cancer cell proliferation and {beta}-catenin, a functionally oncogenic molecule was a direct target gene of miR-320a. Finally, the data of real-time PCR showed the reciprocal relationship between miR-320a and {beta}-catenin's downstream genes in colon cancer tissues. These findings indicate that miR-320a suppresses the growth of colon cancer cells by directly targeting {beta}-catenin, suggesting its application in prognosis prediction and cancer treatment.

  5. Observation of the Cabibbo-suppressed charmed baryon decay {Lambda}{sub {ital c}}{sup +}{r_arrow}{ital p}{phi}

    SciTech Connect (OSTI)

    Alexander, J.P.; Bebek, C.; Berger, B.E.; Berkelman, K.; Bloom, K.; Browder, T.E.; Cassel, D.G.; Cho, H.A.; Coffman, D.M.; Crowcroft, D.S.; Dickson, M.; Drell, P.S.; Dumas, D.J.; Ehrlich, R.; Elia, R.; Gaidarev, P.; Garcia-Sciveres, M.; Gittelman, B.; Gray, S.W.; Hartill, D.L.; Heltsley, B.K.; Henderson, S.; Jones, C.D.; Jones, S.L.; Kandaswamy, J.; Katayama, N.; Kim, P.C.; Kreinick, D.L.; Lee, T.; Liu, Y.; Ludwig, G.S.; Masui, J.; Mevissen, J.; Mistry, N.B.; Ng, C.R.; Nordberg, E.; Patterson, J.R.; Peterson, D.; Riley, D.; Soffer, A.; Avery, P.; Freyberger, A.; Lingel, K.; Prescott, C.; Rodriguez, J.; Yang, S.; Yelton, J.; Brandenburg, G.; Cinabro, D.; Liu, T.; Saulnier, M.; Wilson, R.; Yamamoto, H.; Bergfeld, T.; Eisenstein, B.I.; Ernst, J.; Gladding, G.E.; Gollin, G.D.; Palmer, M.; Selen, M.; Thaler, J.J.; Edwards, K.W.; McLean, K.W.; Ogg, M.; Bellerive, A.; Britton, D.I.; Hyatt, E.R.; Janicek, R.; MacFarlane, D.B.; Patel, P.M.; Spaan, B.; Sadoff, A.J.; Ammar, R.; Baringer, P.; Bean, A.; Besson, D.; Coppage, D.; Copty, N.; Davis, R.; Hancock, N.; Kotov, S.; Kravchenko, I.; Kwak, N.; Kubota, Y.; Lattery, M.; Momayezi, M.; Nelson, J.K.; Patton, S.; Poling, R.; Savinov, V.; Schrenk, S.; Wang, R.; Alam, M.S.; Kim, I.J.; Ling, Z.; Mahmood, A.H.; ONeill, J.J.; Severini, H.; Sun, C.R.; Wappler, F.; Crawford, G.; Fulton, R.; Fujino, D.; Gan, K.K.; Honscheid, K.; Kagan, H.; Kass, R.; Lee, J.; Sung, M.; White, C.; Wolf, A.; Zoeller, M.M.; Fu, X.; Nemati, B.; Ross, W.R.; Skubic, P.; Wood, M.; Bishai, M.; Fast, J.; Gerndt, E.; Hinson, J.W.; Miao, T.; Miller, D.H.; Modesitt, M.; Shibata, E.I.; Shipsey, I.P.; Wang, P.N.; Gibbons, L.; Johnson, S.D.; Kwon, Y.; Roberts, S.; Thorndike, E.H.; Coan, T.E.; Dominick, J.; Fadeyev, V.; Korolkov, I.; Lambrecht, M.; Sanghera, S.; Shelkov, V.; Skwarnicki, T.; Stroynowski, R.; Volobouev, I.; Wei, G.; Artuso, M.; Gao, M.; Goldberg, M.; He, D.; Horwitz, N.; Kopp, S.; Moneti, G.C.; Mountain, R.; Muheim, F.; Mukhin, Y.; Playfer, S.

    1996-02-01

    We report the observation of the Cabibbo-suppressed decays {Lambda}{sub {ital c}}{sup +}{r_arrow}{ital pK{sup {minus}}K{sup +}} and {Lambda}{sub {ital c}}{sup +}{r_arrow}{ital p}{phi} using data collected with the CLEO II detector at CESR. The latter mode, observed for the first time with significant statistics, is of interest as a test of color suppression in charm decays. We have determined the branching ratios for these modes relative to {Lambda}{sub {ital c}}{sup +}{r_arrow}{ital pK{sup {minus}}}{pi}{sup +} and compared our results with theory. {copyright} {ital 1996 The American Physical Society.}

  6. Harmonics suppression of vacuum chamber eddy current induced fields with application to the Superconducting Super Collider (SSC) Low Energy Booster (LEB) Magnets

    SciTech Connect (OSTI)

    Schlueter, R.D.; Halbach, K.

    1991-12-04

    This memo presents the formulation of an expression for eddy currents induced in a thin-walled conductor due to a time-dependent electromagnet field excitation. Then follows an analytical development for prediction of vacuum chamber eddy current induced field harmonics in iron-core electromagnets. A passive technique for harmonics suppression is presented with specific application to the design of the Superconducting Super Collider (SSC) Low Energy B (LEB) Magnets.

  7. Curcumin attenuates glutamate neurotoxicity in the hippocampus by suppression of ER stress-associated TXNIP/NLRP3 inflammasome activation in a manner dependent on AMPK

    SciTech Connect (OSTI)

    Li, Ying; Li, Jia; Li, Shanshan; Li, Yi; Wang, Xiangxiang; Liu, Baolin; Fu, Qiang; Ma, Shiping

    2015-07-01

    Curcumin is a natural polyphenolic compound in Curcuma longa with beneficial effects on neuronal protection. This study aims to investigate the action of curcumin in the hippocampus subjected to glutamate neurotoxicity. Glutamate stimulation induced reactive oxygen species (ROS), endoplasmic reticulum stress (ER stress) and TXNIP/NLRP3 inflammasome activation, leading to damage in the hippocampus. Curcumin treatment in the hippocampus or SH-SY5Y cells inhibited IRE1α and PERK phosphorylation with suppression of intracellular ROS production. Curcumin increased AMPK activity and knockdown of AMPKα with specific siRNA abrogated its inhibitory effects on IRE1α and PERK phosphorylation, indicating that AMPK activity was essential for the suppression of ER stress. As a result, curcumin reduced TXNIP expression and inhibited NLRP3 inflammasome activation by downregulation of NLRP3 and cleaved caspase-1 induction, and thus reduced IL-1β secretion. Specific fluorescent probe and flow cytometry analysis showed that curcumin prevented mitochondrial malfunction and protected cell survival from glutamate neurotoxicity. Moreover, oral administration of curcumin reduced brain infarct volume and attenuated neuronal damage in rats subjected to middle cerebral artery occlusion. Immunohistochemistry showed that curcumin inhibited p-IRE1α, p-PERK and NLRP3 expression in hippocampus CA1 region. Together, these results showed that curcumin attenuated glutamate neurotoxicity by inhibiting ER stress-associated TXNIP/NLRP3 inflammasome activation via the regulation of AMPK, and thereby protected the hippocampus from ischemic insult. - Highlights: • Curcumin attenuates glutamate neurotoxicity in the hippocampus. • Curcumin suppresses ER stress in glutamate-induced hippocampus slices. • Curcumin inhibits TXNIP/NLRP3 inflammasome activation. • Regulation of AMPK by curcumin contributes to suppressing ER stress.

  8. Apigenin suppresses migration and invasion of transformed cells through down-regulation of C-X-C chemokine receptor 4 expression

    SciTech Connect (OSTI)

    Wang, Lei; Kuang, Lisha; Hitron, John Andrew; Son, Young-Ok; Wang, Xin; Budhraja, Amit; Lee, Jeong-Chae; Pratheeshkumar, Poyil; Chen, Gang; Zhang, Zhuo; Luo, Jia; Shi, Xianglin

    2013-10-01

    Environmental exposure to arsenic is known to cause various cancers. There are some potential relationships between cell malignant transformation and C-X-C chemokine receptor type 4 (CXCR4) expressions. Metastasis, one of the major characteristics of malignantly transformed cells, contributes to the high mortality of cells. CXCR4 and its natural chemokine ligand C-X-C motif ligand 12 (CXCL12) play a critical role in metastasis. Therefore, identification of nutritional factors which are able to inhibit CXCR4 is important for protection from environmental arsenic-induced carcinogenesis and for abolishing metastasis of malignantly transformed cells. The present study demonstrates that apigenin (4′,5,7-trihydroxyflavone), a natural dietary flavonoid, suppressed CXCR4 expression in arsenic-transformed Beas-2B cells (B-AsT) and several other types of transformed/cancer cells in a dose- and time-dependent manner. Neither proteasome nor lysosome inhibitor had any effect in reducing the apigenin-induced down-regulation of CXCR4, indicating that apigenin-induced down-regulation of CXCR4 is not due to proteolytic degradation. The down-regulation of CXCR4 is mainly due to the inhibition of nuclear factor κB (NF-κB) transcriptional activity. Apigenin also abolished migration and invasion of transformed cells induced by CXCL12. In a xenograft mouse model, apigenin down-regulated CXCR4 expression and suppressed tumor growth. Taken together, our results show that apigenin is a novel inhibitor of CXCR4 expression. This dietary flavonoid has the potential to suppress migration and invasion of transformed cells and prevent environmental arsenic-induced carcinogenesis. - Highlights: • Apigenin has a potential in preventing environmental arsenic induced carcinogenesis. • Apigenin suppresses CXCR4 in malignant transformed cells in vitro and in vivo. • The down-regulation of CXCR4 is mainly due to inhibition of NF-κB activity.

  9. A non-uniform three-gap buncher cavity with suppression of transverse-electromagnetic mode leakage in the triaxial klystron amplifier

    SciTech Connect (OSTI)

    Qi, Zumin; Zhang, Jun Zhong, Huihuang; Zhu, Danni; Qiu, Yongfeng

    2014-01-15

    The triaxial klystron amplifier is an efficient high power relativistic klystron amplifier operating at high frequencies due to its coaxial structure with large radius. However, the coaxial structures result in coupling problems among the cavities as the TEM mode is not cut-off in the coaxial tube. Therefore, the suppression of the TEM mode leakage, especially the leakage from the buncher cavity to the input cavity, is crucial in the design of a triaxial klystron amplifier. In this paper, a non-uniform three-gap buncher cavity is proposed to suppress the TEM mode leakage. The cold cavity analysis shows that the non-uniform three-gap buncher cavity can significantly suppress the TEM mode generation compared to a uniform three-gap buncher cavity. Particle-in-cell simulation shows that the power leakage to the input cavity is less than 1.5 of the negative power in the buncher cavity and the buncher cavity can efficiently modulate an intense relativistic electron beam free of self-oscillations. A fundamental current modulation depth of 117% is achieved by employing the proposed non-uniform buncher cavity into an X-band triaxial amplifier, which results in the high efficiency generation of high power microwave.

  10. Ionizing Radiation–Inducible miR-27b Suppresses Leukemia Proliferation via Targeting Cyclin A2

    SciTech Connect (OSTI)

    Wang, Bo; Li, Dongping; Kovalchuk, Anna; Litvinov, Dmitry; Kovalchuk, Olga

    2014-09-01

    Purpose: Ionizing radiation is a common carcinogen that is important for the development of leukemia. However, the underlying epigenetic mechanisms remain largely unknown. The goal of the study was to explore microRNAome alterations induced by ionizing radiation (IR) in murine thymus, and to determine the role of IR-inducible microRNA (miRNA/miR) in the development of leukemia. Methods and Materials: We used the well-established C57BL/6 mouse model and miRNA microarray profiling to identify miRNAs that are differentially expressed in murine thymus in response to irradiation. TIB152 human leukemia cell line was used to determine the role of estrogen receptor–α (ERα) in miR-27b transcription. The biological effects of ectopic miR-27b on leukemogenesis were measured by western immunoblotting, cell viability, apoptosis, and cell cycle analyses. Results: Here, we have shown that IR triggers the differential expression of miR-27b in murine thymus tissue in a dose-, time- and sex-dependent manner. miR-27b was significantly down-regulated in leukemia cell lines CCL119 and TIB152. Interestingly, ERα was overexpressed in those 2 cell lines, and it was inversely correlated with miR-27b expression. Therefore, we used TIB152 as a model system to determine the role of ERα in miR-27b expression and the contribution of miR-27b to leukemogenesis. β-Estradiol caused a rapid and transient reduction in miR-27b expression reversed by either ERα-neutralizing antibody or ERK1/2 inhibitor. Ectopic expression of miR-27b remarkably suppressed TIB152 cell proliferation, at least in part, by inducing S-phase arrest. In addition, it attenuated the expression of cyclin A2, although it had no effect on the levels of PCNA, PPARγ, CDK2, p21, p27, p-p53, and cleaved caspase-3. Conclusion: Our data reveal that β-estradiol/ERα signaling may contribute to the down-regulation of miR-27b in acute leukemia cell lines through the ERK1/2 pathway, and that miR-27b may function as a tumor

  11. Suppression of alkylating agent induced cell transformation and gastric ulceration by low-dose alkylating agent pretreatment

    SciTech Connect (OSTI)

    Onodera, Akira; Department of Pharmaceutical Sciences, Kobegakuin University, 1-1-3 Minatojima, Chuo-ku, Kobe 650-8586 ; Kawai, Yuichi; Kashimura, Asako; Ogita, Fumiya; Tsutsumi, Yasuo; Itoh, Norio

    2013-06-14

    Highlights: Low-dose MNNG pretreatment suppresses high-dose MNNG induced in vitro transformation. Gastric ulcers induced by high-dose MNNG decreased after low-dose MNNG pretreatment. Efficacy of low-dose MNNG related to resistance of mutation and oxidative stress. -- Abstract: Exposure to mild stress by chemicals and radiation causes DNA damage and leads to acquired stress resistance. Although the linear no-threshold (LNT) model of safety assessment assumes risk from any dose, evidence from radiological research demonstrates a conflicting hormetic phenomenon known as the hormesis effect. However, the mechanisms underlying radiation hormesis have not yet been clarified, and little is known about the effects of low doses of chemical carcinogens. We analyzed the efficacy of pretreatment with low doses of the alkylating agent N-methyl-N?-nitro-N-nitrosoguanidine (MNNG) on the subsequent induction of cell transformation and gastric ulceration by high-dose MNNG. We used an in vitro Balb/3T3 A31-1-1 cell transformation test and monitored the formation of gastric ulcers in 5-week-old male ICR mice that were administered MNNG in drinking water. The treatment concentrations of MNNG were determined by the cell survival rate and past reports. For low-dose in vitro and in vivo experiments, MNNG was used at 0.028 ?M, and 2.8 ?g/mL, respectively. The frequency of cell transformation induced by 10 ?m MNNG was decreased by low-dose MNNG pretreatment to levels similar to that of spontaneous transformation. In addition, reactive oxygen species (ROS) and mutation frequencies induced by 10 ?m MNNG were decreased by low-dose MNNG pretreatment. Importantly, low-dose MNNG pretreatment had no effect on cell proliferation. In vivo studies showed that the number of gastric ulcers induced by 1 mg/mL MNNG decreased after low-dose MNNG pretreatment. These data indicate that low-dose pretreatment with carcinogens may play a beneficial role in the prevention of chemical toxicity under

  12. Preclinical evaluation of destruxin B as a novel Wnt signaling target suppressing proliferation and metastasis of colorectal cancer using non-invasive bioluminescence imaging

    SciTech Connect (OSTI)

    Yeh, Chi-Tai; Center of Excellence for Cancer Research, Taipei Medical University, Taipei, Taiwan; Department of Surgery, Taipei Medical University-Shuang Ho Hospital, Taipei, Taiwan ; Rao, Yerra Koteswara; Ye, Min; Wu, Wen-Shi; Chang, Tung-Chen; Wang, Liang-Shun; Division of Thoracic Surgery, Department of Surgery, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan ; Wu, Chih-Hsiung; Department of Surgery, Taipei Medical University-Shuang Ho Hospital, Taipei, Taiwan ; Wu, Alexander T.H.; Tzeng, Yew-Min

    2012-05-15

    In continuation to our studies toward the identification of direct anti-cancer targets, here we showed that destruxin B (DB) from Metarhizium anisopliae suppressed the proliferation and induced cell cycle arrest in human colorectal cancer (CRC) HT29, SW480 and HCT116 cells. Additionally, DB induced apoptosis in HT29 cells by decreased expression level of anti-apoptotic proteins Bcl-2 and Bcl-xL while increased pro-apoptotic Bax. On the other hand, DB attenuated Wnt-signaling by downregulation of ?-catenin, Tcf4 and ?-catenin/Tcf4 transcriptional activity, concomitantly with decreased expression of ?-catenin target genes cyclin D1, c-myc and survivin. Furthermore, DB affected the migratory and invasive ability of HT29 cells through suppressed MMPs-2 and -9 enzymatic activities. We also found that DB targeted the MAPK and/or PI3K/Akt pathway by reduced expression of Akt, IKK-?, JNK, NF-?B, c-Jun and c-Fos while increased that of I?B?. Finally, we demonstrated that DB inhibited tumorigenesis in HT29 xenograft mice using non-invasive bioluminescence technique. Consistently, tumor samples from DB-treated mice demonstrated suppressed expression of ?-catenin, cyclin D1, survivin, and endothelial marker CD31 while increased caspase-3 expression. Collectively, our data supports DB as an inhibitor of Wnt/?-catenin/Tcf signaling pathway that may be beneficial in the CRC management. Highlights: ? Destruxin B (DB) inhibited colorectal cancer cells growth and induced apoptosis. ? MAPK and/or PI3K/Akt cascade cooperates in DB induced apoptosis. ? DB affected the migratory and invasive ability of HT29 cells through MMP-9. ? DB attenuated Wnt-signaling components ?-catenin, Tcf4. ? DB attenuated cyclin D1, c-myc, survivin and tumorigenesis in HT29 xenograft mice.

  13. MicroRNA-101 mediates the suppressive effect of laminar shear stress on mTOR expression in vascular endothelial cells

    SciTech Connect (OSTI)

    Chen, Kui; Fan, Wendong; Wang, Xing; Ke, Xiao [Division of Cardiology, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080 (China)] [Division of Cardiology, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080 (China); Wu, Guifu, E-mail: eecpchina@yahoo.com.cn [Key Laboratory on Assisted Circulation, Ministry of Health, Guangzhou 510080 (China)] [Key Laboratory on Assisted Circulation, Ministry of Health, Guangzhou 510080 (China); Hu, Chengheng, E-mail: huchenghengpci@yahoo.com.cn [Division of Cardiology, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080 (China)] [Division of Cardiology, First Affiliated Hospital of Sun Yat-sen University, Guangzhou 510080 (China)

    2012-10-12

    Highlights: Black-Right-Pointing-Pointer Laminar shear stress upregulates miR-101 expression in vascular endothelial cells. Black-Right-Pointing-Pointer miR-101 represses mTOR expression through a specific 3 Prime UTR binding site. Black-Right-Pointing-Pointer Overexpression of miR-101 inhibits G1/S transition and endothelial cell proliferation. Black-Right-Pointing-Pointer Blockade of miR-101 attenuates the suppressive effect of laminar flow on mTOR expression. -- Abstract: Shear stress associated with blood flow plays an important role in regulating gene expression and cell function in endothelial cells (ECs). MicroRNAs (miRNAs) are highly conserved, small non-coding RNAs that negatively regulate the expression of target genes by binding to the mRNA 3 Prime -untranslated region (3 Prime UTR) at the posttranscriptional level involved in diverse cellular processes. This study demonstrates that microRNA-101 in response to laminar shear stress (LSS) is involved in the flow regulation of gene expression in ECs. qRT-PCR analysis showed that miR-101 expression was significantly upregulated in human umbilical vein endothelial cells (HUVECs) exposed to 12 dyn/cm{sup 2} laminar shear stress for 12 h. We found that transfection of miR-101 significantly decreased the luciferase activity of plasmid reporter containing the 3 Prime UTR of mammalian target of rapamycin (mTOR) gene. Western analysis revealed that the protein level of mTOR was significantly reduced in ECs transfected with miR-101. Furthermore, miR-101 overexpression induced cell cycle arrest at the G1/S transition and suppressed endothelial cell proliferation. Finally, transfection of miR-101 inhibitors attenuated the suppressive effects of LSS on mTOR expression, which identified the efficacy of loss-of-function of miR-101 in laminar flow-treated ECs. In conclusion, we have demonstrated that upregulation of miR-101 in response to LSS contributes to the suppressive effects of LSS on mTOR expression and EC

  14. Suppression of roll-off characteristics of organic light-emitting diodes by narrowing current injection/transport area to 50?nm

    SciTech Connect (OSTI)

    Hayashi, Kyohei Inoue, Munetomo; Yoshida, Kou; Nakanotani, Hajime; Mikhnenko, Oleksandr; Nguyen, Thuc-Quyen E-mail: adachi@cstf.kyushu-u.ac.jp; Adachi, Chihaya E-mail: adachi@cstf.kyushu-u.ac.jp

    2015-03-02

    Using e-beam nanolithography, the current injection/transport area in organic light-emitting diodes (OLEDs) was confined into a narrow linear structure with a minimum width of 50?nm. This caused suppression of Joule heating and partial separation of polarons and excitons, so the charge density where the electroluminescent efficiency decays to the half of the initial value (J{sub 0}) was significantly improved. A device with a narrow current injection width of 50?nm exhibited a J{sub 0} that was almost two orders of magnitude higher compared with that of the unpatterned OLED.

  15. Activation of peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}) suppresses postprandial lipidemia through fatty acid oxidation in enterocytes

    SciTech Connect (OSTI)

    Kimura, Rino; Takahashi, Nobuyuki; Murota, Kaeko; Yamada, Yuko; Niiya, Saori; Kanzaki, Noriyuki; Murakami, Yoko; Moriyama, Tatsuya; Goto, Tsuyoshi; Kawada, Teruo

    2011-06-24

    Highlights: {yields} PPAR{alpha} activation increased mRNA expression levels of fatty acid oxidation-related genes in human intestinal epithelial Caco-2 cells. {yields} PPAR{alpha} activation also increased oxygen consumption rate and CO{sub 2} production and decreased secretion of triglyceride and ApoB from Caco-2 cells. {yields} Orally administration of bezafibrate increased mRNA expression levels of fatty acid oxidation-related genes and CO{sub 2} production in small intestinal epithelial cells. {yields} Treatment with bezafibrate decreased postprandial serum concentration of triglyceride after oral injection of olive oil in mice. {yields} It suggested that intestinal lipid metabolism regulated by PPAR{alpha} activation suppresses postprandial lipidemia. -- Abstract: Activation of peroxisome proliferator-activated receptor (PPAR)-{alpha} which regulates lipid metabolism in peripheral tissues such as the liver and skeletal muscle, decreases circulating lipid levels, thus improving hyperlipidemia under fasting conditions. Recently, postprandial serum lipid levels have been found to correlate more closely to cardiovascular diseases than fasting levels, although fasting hyperlipidemia is considered an important risk of cardiovascular diseases. However, the effect of PPAR{alpha} activation on postprandial lipidemia has not been clarified. In this study, we examined the effects of PPAR{alpha} activation in enterocytes on lipid secretion and postprandial lipidemia. In Caco-2 enterocytes, bezafibrate, a potent PPAR{alpha} agonist, increased mRNA expression levels of fatty acid oxidation-related genes, such as acyl-CoA oxidase, carnitine palmitoyl transferase, and acyl-CoA synthase, and oxygen consumption rate (OCR) and suppressed secretion levels of both triglycerides and apolipoprotein B into the basolateral side. In vivo experiments revealed that feeding high-fat-diet containing bezafibrate increased mRNA expression levels of fatty acid oxidation-related genes and

  16. Specific suppression of the in vitro parent anti-hybrid reaction. II. Parameters influencing suppressor cell induction in the F1 hybrid

    SciTech Connect (OSTI)

    Kosmatopoulos, K.; Orbach-Arbouys, S.

    1987-02-01

    In the accompanying paper we have reported that the spleens of B6D2F1 hybrids pretreated with B6 spleen cells 7 days earlier contain a cell which specifically suppresses the in vitro proliferative and cytotoxic B6 anti-B6D2F1 responses. The results we present here concern the in vivo conditions under which this suppressor cell can be induced. Suppressor cell activity appears early after the injection of B6 spleen cells (day +1), increases on Day 7, and disappears by Day 30; it is always detectable after the injection of 5 X 10(7) B6 spleen cells and never after the injection of 1.25 X 10(7) cells, the intermediate dose of 2.5 X 10(7) cells being followed by variable results. This variability is attributable to the age of B6 donor and B6D2F1 recipient mice, and suppression is never observed when 2.5 X 10(7) spleen cells from 6-week-old B6 mice are injected into 6-week-old B6D2F1 hybrids. The suppressor cell is induced by the injection of B6 spleen cells of the Thy-1+ Ly-1-2+ phenotype, even if they are irradiated at 1000 R just before their injection. Lymph node cells from B6 mice induce the suppressor cell, whereas thymocytes do not. Irradiation of B6D2F1 hybrids at 600 or 950 R does not prevent the induction of suppressor cell, nor does thymectomy. Moreover, in the thymectomized or 600 R-irradiated B6D2F1 animals suppression can be induced even by the injection of only 1.25 X 10(7) B6 spleen cells. This phenomenon of specific suppression is not limited to the B6-B6D2F1 genetic combination since it has been observed in all parent-hybrid combinations tested to date.

  17. Suppression of surface charge accumulation on Al{sub 2}O{sub 3}-filled epoxy resin insulator under dc voltage by direct fluorination

    SciTech Connect (OSTI)

    Zhang, Boya; Zhang, Guixin Li, Chuanyang; He, Jinliang; Wang, Qiang; An, Zhenlian

    2015-12-15

    Surface charge accumulation on insulators under high dc voltage is a major factor that may lead to the reduction of insulation levels in gas insulated devices. In this paper, disc insulators made of Al{sub 2}O{sub 3}-filled epoxy resin were surface fluorinated using a F{sub 2}/N{sub 2} mixture (12.5% F{sub 2}) at 50 °C and 0.1 MPa for different durations of 15 min, 30 min and 60 min. A dc voltage was applied to the insulator for 30 min and the charge density on its surface was measured by an electrostatic probe. The results revealed significant lower surface charge densities on the fluorinated insulators in comparison with the original one. Surface conductivity measurements indicated a higher surface conductivity by over three orders of magnitude after fluorination, which would allow the charges to transfer along the surface and thus may suppress their accumulation. Further, attenuated total reflection infrared analysis and surface morphology observations of the samples revealed that the introduction of fluoride groups altered the surface physicochemical properties. These structure changes, especially the physical defects reduced the depth of charge traps in the surface layer, which was verified by the measurement of energy distributions of the electron and hole traps based on the isothermal current theory. The results in this paper demonstrate that fluorination can be a promising and effective method to suppress surface charge accumulation on epoxy insulators in gas insulated devices.

  18. InGaN/GaN multiple-quantum-well light-emitting diodes with a grading InN composition suppressing the Auger recombination

    SciTech Connect (OSTI)

    Zhang, Zi-Hui; Liu, Wei; Ju, Zhengang; Tan, Swee Tiam; Ji, Yun; Kyaw, Zabu; Zhang, Xueliang; Wang, Liancheng; Sun, Xiao Wei E-mail: VOLKAN@stanfordalumni.org; Demir, Hilmi Volkan E-mail: VOLKAN@stanfordalumni.org

    2014-07-21

    In conventional InGaN/GaN light-emitting diodes (LEDs), thin InGaN quantum wells are usually adopted to mitigate the quantum confined Stark effect (QCSE), caused due to strong polarization induced electric field, through spatially confining electrons and holes in small recombination volumes. However, this inevitably increases the carrier density in quantum wells, which in turn aggravates the Auger recombination, since the Auger recombination scales with the third power of the carrier density. As a result, the efficiency droop of the Auger recombination severely limits the LED performance. Here, we proposed and showed wide InGaN quantum wells with the InN composition linearly grading along the growth orientation in LED structures suppressing the Auger recombination and the QCSE simultaneously. Theoretically, the physical mechanisms behind the Auger recombination suppression are also revealed. The proposed LED structure has experimentally demonstrated significant improvement in optical output power and efficiency droop, proving to be an effective solution to this important problem of Auger recombination.

  19. A study of suppressed formation of low-conductivity phases in doped Li7La3Zr2O12 garnets by in situ neutron diffraction

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

    Chen, Yan; Rangasamy, Ezhiylmurugan; dela Cruz, Clarina R.; Liang, Chengdu; An, Ke

    2015-09-28

    Doped Li7La3Zr2O12 garnets, oxide-based solids with good Li+ conductivity and compatibility, show great potential as leading electrolyte material candidates for all-solid-state lithium ion batteries. Still yet, the conductive bulk usually suffers from the presence of secondary phases and the transition towards a low-conductivity tetragonal phase during synthesis. Dopants are designed to stabilize the high-conductive cubic phase and suppress the formation of the low-conductivity phases. In situ neutron diffraction enables a direct observation of the doping effects by monitoring the phase evolutions during garnet synthesis. It reveals the reaction mechanism involving the temporary presence of intermediate phases. The off-stoichiometry due tomore » the liquid Li2CO3 evaporation leads to the residual of the low-conductivity intermediate phase in the as-synthesized bulk. Appropriate doping of an active element may alter the component of the intermediate phases and promote the completion of the reaction. While the dopants aid to stabilize most of the cubic phase, a small amount of tetragonal phase tends to form under a diffusion process. Lastly, the in situ observations provide the guideline of process optimization to suppress the formation of unwanted low-conductivity phases.« less

  20. Pressure Effect on the Structural Transition and Suppression of the High-Spin State in the Triple-Layer T'-La₄Ni₃O₈

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

    Cheng, J.-G.; Zhou, J.-S.; Goodenough, J. B.; Zhou, H. D.; Matsubayashi, K.; Uwatoko, Y.; Kong, P. P.; Jin, C. Q.; Yang, W. G.; Shen, G. Y.

    2012-06-08

    We report a comprehensive high-pressure study on the triple-layer T'-La₄Ni₃O₈ with a suite of experimental probes, including structure determination, magnetic, and transport properties up to 50 GPa. Consistent with a recent ab inito calculation, application of hydrostatic pressure suppresses an insulator-metal spin-state transition at Pc≈6 GPa. However, a low-spin metallic phase does not emerge after the high-spin state is suppressed to the lowest temperature. For P>20 GPa, the ambient T' structure transforms gradually to a T†-type structure, which involves a structural reconstruction from fluorite La–O₂–La blocks under low pressures to rock-salt LaO-LaO blocks under high pressures. Absence of the metallicmore » phase under pressure has been discussed in terms of local displacements of O²⁻ ions in the fluorite block under pressure before a global T† phase is established.« less

  1. Observation of the large magnetocaloric effect and suppression of orbital entropy change in Fe-doped MnV{sub 2}O{sub 4}

    SciTech Connect (OSTI)

    Huang, Z. H.; Luo, X. E-mail: ypsun@issp.ac.cn; Hu, L.; Tan, S. G.; Liu, Y.; Yuan, B.; Chen, J.; Song, W. H.; Sun, Y. P. E-mail: ypsun@issp.ac.cn

    2014-01-21

    We present the structural and magnetic properties of Mn{sub 1−x}Fe{sub x}V{sub 2}O{sub 4} (x = 0.1, 0.2, and 0.3), and investigate the magnetocaloric effect in those compounds. The ferrimagnetic spin ordering is enhanced with the Fe doping at Mn site of MnV{sub 2}O{sub 4}, while the orbital ordering is suppressed. Large magnetic entropy changes up to 3.8 J/kg K as well as the relative cooling power up to 110 J/kg at the field change of 0-2 T for Mn{sub 1−x}Fe{sub x}V{sub 2}O{sub 4} are calculated from the isothermal magnetization measurements. The large orbital entropy change of MnV{sub 2}O{sub 4} is suppressed by the Fe doping, while the spin entropy contribution arising from the strong spin-orbit coupling remains. Moreover, the doping of Fe broadens the temperature span of the large magnetic entropy change and increases the relative cooling power of MnV{sub 2}O{sub 4} by 2.4 times.

  2. Pressure Effect on the Structural Transition and Suppression of the High-Spin State in the Triple-Layer T'-La?Ni?O?

    SciTech Connect (OSTI)

    Cheng, J.-G.; Zhou, J.-S.; Goodenough, J. B.; Zhou, H. D.; Matsubayashi, K.; Uwatoko, Y.; Kong, P. P.; Jin, C. Q.; Yang, W. G.; Shen, G. Y.

    2012-06-08

    We report a comprehensive high-pressure study on the triple-layer T'-La?Ni?O? with a suite of experimental probes, including structure determination, magnetic, and transport properties up to 50 GPa. Consistent with a recent ab inito calculation, application of hydrostatic pressure suppresses an insulator-metal spin-state transition at Pc?6 GPa. However, a low-spin metallic phase does not emerge after the high-spin state is suppressed to the lowest temperature. For P>20 GPa, the ambient T' structure transforms gradually to a T-type structure, which involves a structural reconstruction from fluorite LaO?La blocks under low pressures to rock-salt LaO-LaO blocks under high pressures. Absence of the metallic phase under pressure has been discussed in terms of local displacements of O? ions in the fluorite block under pressure before a global T phase is established.

  3. The suppression effect of a periodic surface with semicircular grooves on the high power microwave long pill-box window multipactor phenomenon

    SciTech Connect (OSTI)

    Zhang, Xue Wang, Yong; Fan, Junjie; Zhong, Yong; Zhang, Rui

    2014-09-15

    To improve the transmitting power in an S-band klystron, a long pill-box window that has a disk with grooves with a semicircular cross section is theoretically investigated and simulated. A Monte-Carlo algorithm is used to track the secondary electron trajectories and analyze the multipactor scenario in the long pill-box window and on the grooved surface. Extending the height of the long-box window can decrease the normal electric field on the surface of the window disk, but the single surface multipactor still exists. It is confirmed that the window disk with periodic semicircular grooves can explicitly suppress the multipactor and predominantly depresses the local field enhancement and the bottom continuous multipactor. The difference between semicircular and sharp boundary grooves is clarified numerically and analytically.

  4. Suppression of the Critical Temperature of Superconducting NdFeAs(OF) Single Crystals by Kondo-Like Defect Sites Induced by {alpha}-Particle Irradiation

    SciTech Connect (OSTI)

    Tarantini, C.; Gurevich, A.; Larbalestier, D. C.; Putti, M.; Shen, Y.; Singh, R. K.; Rowell, J. M.; Newman, N.; Cheng Peng; Jia Ying; Wen Haihu

    2010-02-26

    We report the effect of {alpha}-particle irradiation on the reduction of the critical temperature T{sub c} of a NdFeAs(OF) single crystal. Our data indicate that irradiation defects cause both nonmagnetic and magnetic scattering, resulting in the Kondo-like excess resistance {Delta}{rho}(T)propor tolnT over 2 decades in temperatures above T{sub c}. The critical density of magnetic irradiation defects which suppresses T{sub c} is found to be much higher than those for cuprates and multiband BCS superconductors. We suggest that such anomalously weak pair breaking by irradiation defects indicates that magnetic scattering in pnictides is coupled with pairing interactions mediated by spin fluctuations.

  5. Albendazole inhibits endothelial cell migration, tube formation, vasopermeability, VEGF receptor-2 expression and suppresses retinal neovascularization in ROP model of angiogenesis

    SciTech Connect (OSTI)

    Pourgholami, Mohammad H.; Khachigian, Levon M.; Fahmy, Roger G.; Badar, Samina; Wang, Lisa; Chu, Stephanie Wai Ling; Morris, David Lawson

    2010-07-09

    The angiogenic process begins with the cell proliferation and migration into the primary vascular network, and leads to vascularization of previously avascular tissues and organs as well to growth and remodeling of the initially homogeneous capillary plexus to form a new microcirculation. Additionally, an increase in microvascular permeability is a crucial step in angiogenesis. Vascular endothelial growth factor (VEGF) plays a central role in angiogenesis. We have previously reported that albendazole suppresses VEGF levels and inhibits malignant ascites formation, suggesting a possible effect on angiogenesis. This study was therefore designed to investigate the antiangiogenic effect of albendazole in non-cancerous models of angiogenesis. In vitro, treatment of human umbilical vein endothelial cells (HUVECs) with albendazole led to inhibition of tube formation, migration, permeability and down-regulation of the VEGF type 2 receptor (VEGFR-2). In vivo albendazole profoundly inhibited hyperoxia-induced retinal angiogenesis in mice. These results provide new insights into the antiangiogenic effects of albendazole.

  6. Hydrogen-doping stabilized metallic VO{sub 2} (R) thin films and their application to suppress Fabry-Perot resonances in the terahertz regime

    SciTech Connect (OSTI)

    Zhao, Yong; Pan, Xuan; Bernussi, Ayrton A.; Fan, Zhaoyang, E-mail: Zhaoyang.Fan@ttu.edu [Department of Electrical and Computer Engineering and Nano Tech Center, Lubbock, Texas 79409 (United States); Karaoglan-Bebek, Gulten [Department of Physics and Nano Tech Center, Lubbock, Texas 79409 (United States); Holtz, Mark [Department of Physics and MSEC, Texas State University, San Marcos, Texas 78666 (United States)

    2014-06-16

    We demonstrate that catalyst-assisted hydrogen spillover doping of VO{sub 2} thin films significantly alters the metal-insulator transition characteristics and stabilizes the metallic rutile phase at room temperature. With hydrogen inserted into the VO{sub 2} lattice, high resolution X-ray diffraction reveals expansion of the V-V chain separation when compared to the VO{sub 2}(R) phase. The donated free electrons, possibly from O-H bond formation, stabilize the VO{sub 2}(R) to low temperatures. By controlling the amount of dopants to obtain mixed insulating and metallic phases, VO{sub 2} resistivity can be continuously tuned until a critical condition is achieved that suppresses Fabry-Perot resonances. Our results demonstrate that hydrogen spillover is an effective technique to tune the electrical and optical properties of VO{sub 2} thin films.

  7. Strange quark suppression and strange hadron production in pp collisions at energies available at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider

    SciTech Connect (OSTI)

    Long Haiyan; Feng Shengqin; Zhou Daimei; Yan Yuliang; Ma Hailiang; Sa Benhao

    2011-09-15

    The parton and hadron cascade model PACIAE based on PYTHIA is utilized to systematically investigate strange particle production in pp collisions at energies available at the BNL Relativistic Heavy Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC). Globally speaking, the PACIAE results of the strange particle rapidity density at midrapidity and the transverse momentum distribution are better than those of PYTHIA (default) in comparison with STAR and ALICE experimental data. This may represent the importance of the parton and hadron rescatterings, as well as the reduction mechanism of strange quark suppression, added in the PACIAE model. The K/{pi} ratios as a function of reaction energy in pp collisions from CERN Super Proton Synchrotron (SPS) to LHC energies are also analyzed in this paper.

  8. Corrigendum to “Suppression of Υ production in d+Au and Au+Au collisions at √ SNN = 200 GeV" [Phys. Lett. B 735 (2014) 127-137

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

    Adamczyk, L.

    2015-04-01

    We report measurements of Υ meson production in p + p, d + Au, and Au+Au collisions using the STAR detector at RHIC. We compare the Υ yield to the measured cross section in p + p collisions in order to quantify any modifications of the yield in cold nuclear matter using d + Au data and in hot nuclear matter using Au+Au data separated into three centrality classes. Our p + p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for Upsilon (1S + 2S + 3S) in themore » rapidity range |y| < 1 in d + Au collisions of RdAu = 0.79 ± 0.24(stat.) ± 0.03(syst.) ± 0.10(p + p syst.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au + Au collisions, we measure a nuclear modification factor of R AA = 0.49 ±0.1(stat.) ±0.02(syst.) ±0.06(p + p syst.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state Upsilon mesons in Au + Au collisions. The additional suppression in Au + Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined Quark–Gluon Plasma. However, understanding the suppression seen in d + Au is still needed before any definitive statements about the nature of the suppression in Au + Au can be made.« less

  9. Corrigendum to “Suppression of Υ production in d+Au and Au+Au collisions at √ SNN = 200 GeV" [Phys. Lett. B 735 (2014) 127-137

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

    Adamczyk, L.

    2015-04-01

    We report measurements of Υ meson production in p + p, d + Au, and Au+Au collisions using the STAR detector at RHIC. We compare the Υ yield to the measured cross section in p + p collisions in order to quantify any modifications of the yield in cold nuclear matter using d + Au data and in hot nuclear matter using Au+Au data separated into three centrality classes. Our p + p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for Upsilon (1S + 2S + 3S) in themore »rapidity range |y| dAu = 0.79 ± 0.24(stat.) ± 0.03(syst.) ± 0.10(p + p syst.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au + Au collisions, we measure a nuclear modification factor of R AA = 0.49 ±0.1(stat.) ±0.02(syst.) ±0.06(p + p syst.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state Upsilon mesons in Au + Au collisions. The additional suppression in Au + Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined Quark–Gluon Plasma. However, understanding the suppression seen in d + Au is still needed before any definitive statements about the nature of the suppression in Au + Au can be made.« less

  10. Corrigendum to Suppression of ? production in d+Au and Au+Au collisions at ? SNN = 200 GeV" [Phys. Lett. B 735 (2014) 127-137

    SciTech Connect (OSTI)

    Adamczyk, L.

    2015-04-01

    We report measurements of ? meson production in p + p, d + Au, and Au+Au collisions using the STAR detector at RHIC. We compare the ? yield to the measured cross section in p + p collisions in order to quantify any modifications of the yield in cold nuclear matter using d + Au data and in hot nuclear matter using Au+Au data separated into three centrality classes. Our p + p measurement is based on three times the statistics of our previous result. We obtain a nuclear modification factor for Upsilon (1S + 2S + 3S) in the rapidity range |y| < 1 in d + Au collisions of RdAu = 0.79 0.24(stat.) 0.03(syst.) 0.10(p + p syst.). A comparison with models including shadowing and initial state parton energy loss indicates the presence of additional cold-nuclear matter suppression. Similarly, in the top 10% most-central Au + Au collisions, we measure a nuclear modification factor of R AA = 0.49 0.1(stat.) 0.02(syst.) 0.06(p + p syst.), which is a larger suppression factor than that seen in cold nuclear matter. Our results are consistent with complete suppression of excited-state Upsilon mesons in Au + Au collisions. The additional suppression in Au + Au is consistent with the level expected in model calculations that include the presence of a hot, deconfined QuarkGluon Plasma. However, understanding the suppression seen in d + Au is still needed before any definitive statements about the nature of the suppression in Au + Au can be made.