Sample records for age-related macular degeneration

  1. age-related macular degeneration: Topics by E-print Network

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

    were conducted blind to risk genotypes and the results analyzed using univariate and multivariate (logistic regression) analysis. Results: IgG seropositivity to C. pneumoniae...

  2. Mitochondrial DNA haplogroups confer differences in risk for age-related macular degeneration: a case control study

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    may change the retinal bioenergetics and play a significantmay change retinal bioenergetics and energy production

  3. Mitochondrial DNA haplogroups confer differences in risk for age-related macular degeneration: a case control study

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    are critical for energy production, the haplogroup-relatedbioenergetics and energy production levels causing a)the mitochondrial energy production efficiency [8]. Sperm

  4. Mitochondrial DNA Variants Mediate Energy Production and Expression Levels for CFH, C3 and EFEMP1 Genes: Implications for Age-Related Macular Degeneration

    E-Print Network [OSTI]

    2013-01-01T23:59:59.000Z

    DNA Variants Mediate Energy Production and Expression Levelsmediate not only energy production and cell growth, but alsoDNA Variants Mediate Energy Production and Expression Levels

  5. Arterial Thromboembolic Events following Intravitreal Vascular Endothelial Growth Factor Inhibitor Therapy for Age-Related Macular Degeneration in Regular Clinical Practice

    E-Print Network [OSTI]

    Fafowora, Oluwatoyin Folasade

    2015-01-01T23:59:59.000Z

    of Avastin and Lucentis: off-label versus goldstandard.but Michels showed that off-label intravitreal use producedevents. Genentech nvAMD off-label 149 KDa full-length,

  6. Original article Age-related changes in apparent digestibility

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Original article Age-related changes in apparent digestibility in growing kittens E. Jean HARPER kitten to digest protein, fat, carbohydrate, dry-matter and energy were assessed. Kittens were divided access to food. Apparent digestibility of the two diets, and kitten bodyweights were measured over a 24

  7. Accident sequence precursor events with age-related contributors

    SciTech Connect (OSTI)

    Murphy, G.A.; Kohn, W.E.

    1995-12-31T23:59:59.000Z

    The Accident Sequence Precursor (ASP) Program at ORNL analyzed about 14.000 Licensee Event Reports (LERs) filed by US nuclear power plants 1987--1993. There were 193 events identified as precursors to potential severe core accident sequences. These are reported in G/CR-4674. Volumes 7 through 20. Under the NRC Nuclear Plant Aging Research program, the authors evaluated these events to determine the extent to which component aging played a role. Events were selected that involved age-related equipment degradation that initiated an event or contributed to an event sequence. For the 7-year period, ORNL identified 36 events that involved aging degradation as a contributor to an ASP event. Except for 1992, the percentage of age-related events within the total number of ASP events over the 7-year period ({approximately}19%) appears fairly consistent up to 1991. No correlation between plant ape and number of precursor events was found. A summary list of the age-related events is presented in the report.

  8. age-related myelin dynamics: Topics by E-print Network

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

    age-related myelin dynamics First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Age related changes in...

  9. Neurobiology of Aging xxx (2006) xxxxxx Age-related changes in brain activation during

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    Neurobiology of Aging xxx (2006) xxx­xxx Age-related changes in brain activation during a delayed. / Neurobiology of Aging xxx (2006) xxx­xxx impairment in several different memory variables [78], including WM [9

  10. Hydraulic limitation not declining nitrogen availability causes the age-related photosynthetic decline in loblolly

    E-Print Network [OSTI]

    DeLucia, Evan H.

    Hydraulic limitation not declining nitrogen availability causes the age-related photosynthetic capacity and thus decreases GPP with increasing age; and (2) hydraulic limitations increasingly induce conservative with age. We conclude that hydraulic limitation increasingly limits the photosyn- thetic rates

  11. Examining Age-Related Use of Visual Imagery Subprocesses in Children

    E-Print Network [OSTI]

    Oliver, Brittney

    2011-08-08T23:59:59.000Z

    This study examined the age-related ability of children (7 to 11 years) and adults to use visual imagery in tasks requiring the subprocesses of imagery generation, maintenance and inspection. Previous work had shown that young children...

  12. High Temperature Requirement Factor A1 (HTRA1) Gene Regulates Angiogenesis through Transforming Growth

    E-Print Network [OSTI]

    Function in Animals, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan for AMD. Age-related macular degeneration (AMD)5 is the leading cause of blindness among elderly patients

  13. Use Of Green Porphyrinsto Treat Neovasculature In The Eyes

    DOE Patents [OSTI]

    Levy, Julia (Vancouver, CA); Miller, Joan W. (Boston, MA); Gradoudas, Evangelos S. (Boston, MA); Hasan, Tayyaba (Arlington, MA); Schmidt-Erfurth, Ursula (Luebeck, DE)

    1998-08-25T23:59:59.000Z

    Photodynamic therapy of conditions of the eye characterized by unwanted neovasculature, such as age-related macular degeneration, is effective using green porphyrins as photoactive agents, preferably as liposomal compositions.

  14. Aging assessment of reactor instrumentation and protection system components. Aging-related operating experiences

    SciTech Connect (OSTI)

    Gehl, A.C.; Hagen, E.W. [Oak Ridge National Lab., TN (United States)

    1992-07-01T23:59:59.000Z

    A study of the aging-related operating experiences throughout a five-year period (1984--1988) of six generic instrumentation modules (indicators, sensors, controllers, transmitters, annunciators, and recorders) was performed as a part of the Nuclear Plant Aging Research Program. The effects of aging from operational and environmental stressors were characterized from results depicted in Licensee Event Reports (LERs). The data are graphically displayed as frequency of events per plant year for operating plant ages from 1 to 28 years to determine aging-related failure trend patterns. Three main conclusions were drawn from this study: (1) Instrumentation and control (I&C) modules make a modest contribution to safety-significant events: 17% of LERs issued during 1984--1988 dealt with malfunctions of the six I&C modules studied, and 28% of the LERs dealing with these I&C module malfunctions were aging related (other studies show a range 25--50%); (2) Of the six modules studied, indicators, sensors, and controllers account for the bulk (83%) of aging-related failures; and (3) Infant mortality appears to be the dominant aging-related failure mode for most I&C module categories (with the exception of annunciators and recorders, which appear to fail randomly).

  15. Geometric phases for non-degenerate and degenerate mixed states

    E-Print Network [OSTI]

    K. Singh; D. M. Tong; K. Basu; J. L. Chen; J. F. Du

    2003-04-10T23:59:59.000Z

    This paper focuses on the geometric phase of general mixed states under unitary evolution. Here we analyze both non-degenerate as well as degenerate states. Starting with the non-degenerate case, we show that the usual procedure of subtracting the dynamical phase from the total phase to yield the geometric phase for pure states, does not hold for mixed states. To this end, we furnish an expression for the geometric phase that is gauge invariant. The parallelity conditions are shown to be easily derivable from this expression. We also extend our formalism to states that exhibit degeneracies. Here with the holonomy taking on a non-abelian character, we provide an expression for the geometric phase that is manifestly gauge invariant. As in the case of the non-degenerate case, the form also displays the parallelity conditions clearly. Finally, we furnish explicit examples of the geometric phases for both the non-degenerate as well as degenerate mixed states.

  16. age-related nuclear cataracts: Topics by E-print Network

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

    age-related nuclear cataracts First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Electron tomography of...

  17. age-related nuclear cataract: Topics by E-print Network

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

    age-related nuclear cataract First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Electron tomography of...

  18. Paternal age related schizophrenia (PARS): latent subgroups detected by k-means clustering analysis

    E-Print Network [OSTI]

    Ahn, Hongshik

    1 Paternal age related schizophrenia (PARS): latent subgroups detected by k-means clustering of schizophrenia with distinct etiology, pathophysiology and symptoms. This study uses a k-means clustering-R) and olfaction (University of Pennsylvania Smell Identification Test; UPSIT). We conducted a series of k-means

  19. Age-Related Differences in Emotional Reactivity, Regulation, and Rejection Sensitivity in Adolescence

    E-Print Network [OSTI]

    Ochsner, Kevin

    Age-Related Differences in Emotional Reactivity, Regulation, and Rejection Sensitivity Massachusetts Institute of Technology James J. Gross Stanford University Katherine A. Remy and Kevin N. Ochsner reactivity or emotion regulation. Study 1 addressed this question by presenting healthy individuals aged 10

  20. age-related cortical brain: Topics by E-print Network

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

    age-related cortical brain First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Role of microstructure in...

  1. Neurobiology of Aging 32 (2011) 669679 Age-related trends in saccade characteristics among the elderly

    E-Print Network [OSTI]

    Munoz, Douglas Perry

    2011-01-01T23:59:59.000Z

    Neurobiology of Aging 32 (2011) 669­679 Age-related trends in saccade characteristics among of Psychology, Queen's University, Kingston, Ontario, Canada e CIHR Group in Sensory-Motor Systems, Queen in reaction time also correlated positively with age in both saccade tasks. Voluntary saccade control

  2. Single Enrichment Variables Differentially Reduce Age-Related Memory Decline in Female Mice

    E-Print Network [OSTI]

    Frick, Karyn M.

    Single Enrichment Variables Differentially Reduce Age-Related Memory Decline in Female Mice Lauren to determine how different elements of enrichment, for example, cognitive stimu- lation and voluntary exercise), running wheels alone (exercise), or both toys and running wheels (complex enrichment) for 4 weeks prior

  3. Purpose. To evaluate the reliability and validity of a portable instrument for measuring macular pigment optical density.

    E-Print Network [OSTI]

    macular pigment optical density. Methods. The instrument is small, uses light emitting diodes as light

  4. AGE-RELATED DEGRADATION OF NUCLEAR POWER PLANT STRUCTURES AND COMPONENTS.

    SciTech Connect (OSTI)

    BRAVERMAN,J.

    1999-03-29T23:59:59.000Z

    This paper summarizes and highlights the results of the initial phase of a research project on the assessment of aged and degraded structures and components important to the safe operation of nuclear power plants (NPPs). A review of age-related degradation of structures and passive components at NPPs was performed. Instances of age-related degradation have been collected and reviewed. Data were collected from plant generated documents such as Licensing Event Reports, NRC generic communications, NUREGs and industry reports. Applicable cases of degradation occurrences were reviewed and then entered into a computerized database. The results obtained from the review of degradation occurrences are summarized and discussed. Various trending analyses were performed to identify which structures and components are most affected, whether degradation occurrences are worsening, and what are the most common aging mechanisms. The paper also discusses potential aging issues and degradation-susceptible structures and passive components which would have the greatest impact on plant risk.

  5. Chronic stress and age-related increases in the proinflammatory cytokine interleukin-6

    E-Print Network [OSTI]

    Kiecolt-Glaser, J. K.; Preacher, K. J.; MacCallum, R. C.; Atkinson, Cathie; Malarkey, W. B.; Glaser, R.

    2003-01-01T23:59:59.000Z

    Chronic stress and age-related increases in the proinflammatory cytokine IL-6 Janice K. Kiecolt-Glaser* ?? , Kristopher J. Preacher ? , Robert C. MacCallum ? , Cathie Atkinson*, William B. Malarkey ?H20648 , and Ronald Glaser ?? ** ?? Departments... of *Psychiatry, H20648 Internal Medicine, and **Molecular Virology, Immunology, and Medical Genetics, Ohio State University College of Medicine, Columbus, OH 43210; ? Department of Psychology, ? Institute for Behavioral Medicine Research, and ? Comprehensive...

  6. Highway crash rates and age-related driver limitations: Literature review and evaluation of data bases

    SciTech Connect (OSTI)

    Hu, P.S. [Oak Ridge National Lab., TN (United States)] [Oak Ridge National Lab., TN (United States); Young, J.R. [Tennessee Univ., Knoxville, TN (United States)] [Tennessee Univ., Knoxville, TN (United States); Lu, An [Oak Ridge Associated Universities, Inc., TN (United States)] [Oak Ridge Associated Universities, Inc., TN (United States)

    1993-08-01T23:59:59.000Z

    American society is undergoing a major demographic transformation that is resulting in a larger proportion of older individuals in the population. Moreover, recent travel surveys show that an increasing number of older individuals are licensed to drive and that they drive more than their same age cohort a decade ago. However, they continue to take shorter trips than younger drivers and they avoid driving during congested hours. This recent demographic transformation in our society, the graying of America, coupled with the increasing mobility of the older population impose a serious highway safety issue that cannot be overlooked. Some of the major concerns are the identification of ``high-risk`` older drivers and the establishment of licensing guidelines and procedures that are based on conclusive scientific evidence. Oak Ridge National Laboratory`s (ORNL) objectives in this project can be characterized by the following tasks: Review and evaluate the 1980 American Association of Motor Vehicle Administrators (AAMVA) and National Highway Traffic Safety Administration (NHTSA) licensing guidelines. Determine whether the license restriction recommended in the 1980 AAMVA and NHTSA guidelines was based on scientific evidence or on judgement of medical advisors. Identify in the scientific literature any medical conditions which are found to be highly associated with highway crashes, and which are not mentioned in the 1980 guidelines. Summarize States` current licensing practices for drivers with age-related physical and mental limitations. Identify potential data sources to establish conclusive evidence on age-related functional impairments and highway crashes.

  7. Neuroscience Letters 366 (2004) 5862 Age-related effects of bilateral frontal eye fields lesions on rapid eye

    E-Print Network [OSTI]

    Zhou, Yi-Feng

    Neuroscience Letters 366 (2004) 58­62 Age-related effects of bilateral frontal eye fields lesions on rapid eye movements during REM sleep in rhesus monkeys Shan Yua,b,1, Ning Liub,1, Tao Zengb,c, Shaohua Received 14 January 2004; received in revised form 7 April 2004; accepted 8 May 2004 Abstract Rapid eye

  8. Reorganization of visual processing in macular degeneration: Replication and clues about the role of foveal loss q

    E-Print Network [OSTI]

    Baker, Chris I.

    - lowing loss of visual input as a result of optic radiation damage (Dilks, Serences, Rosenau, Yantis, & Mc

  9. Reorganization of visual processing in macular degeneration: Replication and clues about the role of foveal loss q

    E-Print Network [OSTI]

    Kanwisher, Nancy

    study reported reorganization fol- lowing loss of visual input as a result of optic radiation damage

  10. AGE-RELATED BRAIN CHOLINESTERASE INHIBITION KINETICS FOLLOWING IN VITRO INCUBATION WITH CHLORPYRIFOS-OXON AND DIAZINON-OXON

    SciTech Connect (OSTI)

    Kousba, Ahmed A.; Poet, Torka S.; Timchalk, Chuck

    2007-01-01T23:59:59.000Z

    Chlorpyrifos and diazinon are two commonly used organophosphorus (OP) insecticides, and their primary mechanism of action involves the inhibition of acetylcholinesterase (AChE) by their metabolites chlorpyrifos-oxon (CPO) and diazinon-oxon (DZO), respectively. The study objectives were to assess the in vitro age-related inhibition kinetics of neonatal rat brain cholinesterase (ChE) by estimating the bimolecular inhibitory rate constant (ki) values for CPO and DZO. Brain ChE inhibition and ki values following CPO and DZO incubation with neonatal Sprague-Dawley rats rat brain homogenates were determined at post natal day (PND) -5, -12 and -17 and compared with the corresponding inhibition and ki values obtained in the adult rat. A modified Ellman method was utilized for measuring the ChE activity. Chlorpyrifos-oxon resulted in greater ChE inhibition than DZO consistent with the estimated ki values of both compounds. Neonatal brain ChE inhibition kinetics exhibited a marked age-related sensitivity to CPO, where the order of ChE inhibition was PND-5 > PND-7 > PND-17 with ki values of 0.95, 0.50 and 0.22 nM-1hr-1, respectively. In contrast, DZO did not exhibit an age-related inhibition of neonatal brain ChE, and the estimated ki value at all PND ages was 0.02 nM-1hr-1. These results demonstrated an age- and chemical-related OP-selective inhibition of rat brain ChE which may be critically important in understanding the potential sensitivity of juvenile humans to specific OP exposures.

  11. Age-related changes in the plasticity and toughness of human cortical bone at multiple length-scales

    SciTech Connect (OSTI)

    Zimmermann, Elizabeth A.; Schaible, Eric; Bale, Hrishikesh; Barth, Holly D.; Tang, Simon Y.; Reichert, Peter; Busse, Bjoern; Alliston, Tamara; Ager III, Joel W.; Ritchie, Robert O.

    2011-08-10T23:59:59.000Z

    The structure of human cortical bone evolves over multiple length-scales from its basic constituents of collagen and hydroxyapatite at the nanoscale to osteonal structures at nearmillimeter dimensions, which all provide the basis for its mechanical properties. To resist fracture, bone’s toughness is derived intrinsically through plasticity (e.g., fibrillar sliding) at structural-scales typically below a micron and extrinsically (i.e., during crack growth) through mechanisms (e.g., crack deflection/bridging) generated at larger structural-scales. Biological factors such as aging lead to a markedly increased fracture risk, which is often associated with an age-related loss in bone mass (bone quantity). However, we find that age-related structural changes can significantly degrade the fracture resistance (bone quality) over multiple lengthscales. Using in situ small-/wide-angle x-ray scattering/diffraction to characterize sub-micron structural changes and synchrotron x-ray computed tomography and in situ fracture-toughness measurements in the scanning electron microscope to characterize effects at micron-scales, we show how these age-related structural changes at differing size-scales degrade both the intrinsic and extrinsic toughness of bone. Specifically, we attribute the loss in toughness to increased non-enzymatic collagen cross-linking which suppresses plasticity at nanoscale dimensions and to an increased osteonal density which limits the potency of crack-bridging mechanisms at micron-scales. The link between these processes is that the increased stiffness of the cross-linked collagen requires energy to be absorbed by “plastic” deformation at higher structural levels, which occurs by the process of microcracking.

  12. A Monte Carlo algorithm for degenerate plasmas

    SciTech Connect (OSTI)

    Turrell, A.E., E-mail: a.turrell09@imperial.ac.uk; Sherlock, M.; Rose, S.J.

    2013-09-15T23:59:59.000Z

    A procedure for performing Monte Carlo calculations of plasmas with an arbitrary level of degeneracy is outlined. It has possible applications in inertial confinement fusion and astrophysics. Degenerate particles are initialised according to the Fermi–Dirac distribution function, and scattering is via a Pauli blocked binary collision approximation. The algorithm is tested against degenerate electron–ion equilibration, and the degenerate resistivity transport coefficient from unmagnetised first order transport theory. The code is applied to the cold fuel shell and alpha particle equilibration problem of inertial confinement fusion.

  13. Total absorption by degenerate critical coupling

    SciTech Connect (OSTI)

    Piper, Jessica R., E-mail: jrylan@stanford.edu; Liu, Victor; Fan, Shanhui, E-mail: shanhui@stanford.edu [Ginzton Laboratory, Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)

    2014-06-23T23:59:59.000Z

    We consider a mirror-symmetric resonator with two ports. We show that, when excited from a single port, complete absorption can be achieved through critical coupling to degenerate resonances with opposite symmetry. Moreover, any time two resonances with opposite symmetry are degenerate in frequency and absorption is always significantly enhanced. In contrast, when two resonances with the same symmetry are nearly degenerate, there is no absorption enhancement. We numerically demonstrate these effects using a graphene monolayer on top of a photonic crystal slab, illuminated from a single side in the near-infrared.

  14. Admissibility Conditions for Degenerate Cyclotomic BMW Algebras

    E-Print Network [OSTI]

    Goodman, Frederick M

    2009-01-01T23:59:59.000Z

    We study admissibility conditions for the parameters of degenerate cyclotomic BMW algebras. We show that the u-admissibility condition of Ariki, Mathas and Rui is equivalent to a simple module theoretic condition.

  15. Shear viscosity of degenerate electron matter

    E-Print Network [OSTI]

    P. S. Shternin

    2008-03-27T23:59:59.000Z

    We calculate the partial electron shear viscosity $\\eta_{ee}$ limited by electron-electron collisions in a strongly degenerate electron gas taking into account the Landau damping of transverse plasmons. The Landau damping strongly suppresses $\\eta_{ee}$ in the domain of ultrarelativistic degenerate electrons and modifies its %asymptotic temperature behavior. The efficiency of the electron shear viscosity in the cores of white dwarfs and envelopes of neutron stars is analyzed.

  16. Received: 24 July 2008, Accepted: 24 July 2008, Published online in Wiley InterScience: 2009 Engineered 5S ribosomal RNAs displaying

    E-Print Network [OSTI]

    Fox, George

    being incorporated into ribosomes and without obvious effects on the host cells. In this work, we selection from a very large pool of $1015 randomized polynucleotides which is narrowed down to one or a few, but plays an essential role in tumor growth and age-related macular degeneration (AMD). Pegaptanib sodium

  17. Degenerate Quantum Codes for Pauli Channels

    E-Print Network [OSTI]

    Graeme Smith; John A. Smolin

    2006-12-23T23:59:59.000Z

    A striking feature of quantum error correcting codes is that they can sometimes be used to correct more errors than they can uniquely identify. Such degenerate codes have long been known, but have remained poorly understood. We provide a heuristic for designing degenerate quantum codes for high noise rates, which is applied to generate codes that can be used to communicate over almost any Pauli channel at rates that are impossible for a nondegenerate code. The gap between nondegenerate and degenerate code performance is quite large, in contrast to the tiny magnitude of the only previous demonstration of this effect. We also identify a channel for which none of our codes outperform the best nondegenerate code and show that it is nevertheless quite unlike any channel for which nondegenerate codes are known to be optimal.

  18. Ion acoustic shock waves in degenerate plasmas

    SciTech Connect (OSTI)

    Akhtar, N. [Theoretical Plasma Physics Division, PINSTECH, Nilore, Islamabad 44000 Pakistan (Pakistan); Hussain, S. [Theoretical Plasma Physics Division, PINSTECH, Nilore, Islamabad 44000 Pakistan (Pakistan); Department of Physics and Applied Mathematics, PIEAS, Nilore, Islamabad 44000 Pakistan (Pakistan)

    2011-07-15T23:59:59.000Z

    Korteweg de Vries Burgers equation for negative ion degenerate dissipative plasma has been derived using reductive perturbation technique. The quantum hydrodynamic model is used to study the quantum ion acoustic shock waves. The effects of different parameters on quantum ion acoustic shock waves are studied. It is found that quantum parameter, electrons Fermi temperature, temperature of positive and negative ions, mass ratio of positive to negative ions, viscosity, and density ratio have significant impact on the shock wave structure in negative ion degenerate plasma.

  19. Identification and Assessment of Material Models for Age-Related Degradation of Structures and Passive Components in Nuclear Power Plants

    SciTech Connect (OSTI)

    Nie,J.; Braverman, J.; Hofmayer, C.; Kim, M. K.; Choi, I-K.

    2009-04-27T23:59:59.000Z

    When performing seismic safety assessments of nuclear power plants (NPPs), the potential effects of age-related degradation on structures, systems, and components (SSCs) should be considered. To address the issue of aging degradation, the Korea Atomic Energy Research Institute (KAERI) has embarked on a five-year research project to develop a realistic seismic risk evaluation system which will include the consideration of aging of structures and components in NPPs. Three specific areas that are included in the KAERI research project, related to seismic probabilistic risk assessment (PRA), are probabilistic seismic hazard analysis, seismic fragility analysis including the effects of aging, and a plant seismic risk analysis. To support the development of seismic capability evaluation technology for degraded structures and components, KAERI entered into a collaboration agreement with Brookhaven National Laboratory (BNL) in 2007. The collaborative research effort is intended to continue over a five year period with the goal of developing seismic fragility analysis methods that consider the potential effects of age-related degradation of SSCs, and using these results as input to seismic PRAs. In the Year 1 scope of work BNL collected and reviewed degradation occurrences in US NPPs and identified important aging characteristics needed for the seismic capability evaluations that will be performed in the subsequent evaluations in the years that follow. This information is presented in the Annual Report for the Year 1 Task, identified as BNL Report-81741-2008 and also designated as KAERI/RR-2931/2008. The report presents results of the statistical and trending analysis of this data and compares the results to prior aging studies. In addition, the report provides a description of U.S. current regulatory requirements, regulatory guidance documents, generic communications, industry standards and guidance, and past research related to aging degradation of SSCs. This report describes the research effort performed by BNL for the Year 2 scope of work. This research focused on methods that could be used to represent the long-term behavior of materials used at NPPs. To achieve this BNL reviewed time-dependent models which can approximate the degradation effects of the key materials used in the construction of structures and passive components determined to be of interest in the Year 1 effort. The intent was to review the degradation models that would cover the most common time-dependent changes in material properties for concrete and steel components.

  20. Affine and degenerate affine BMW algebras: Actions on tensor space

    E-Print Network [OSTI]

    Ram, Arun

    Affine and degenerate affine BMW algebras: Actions on tensor space Zajj Daugherty Department Actions of classical type tantalizers 8 2.1 The degenerate affine BMW algebra action . . . . . . . . . . . . . . . . . . . . . 13 2.2 The affine BMW algebra action . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 3

  1. Effect of trapping in degenerate quantum plasmas

    SciTech Connect (OSTI)

    Shah, H. A.; Qureshi, M. N. S. [Department of Physics, GC University, Lahore 54000 (Pakistan); Tsintsadze, N. [Department of Physics, GC University, Lahore 54000 (Pakistan); Salam Chair, GC University, Lahore 54000 (Pakistan)

    2010-03-15T23:59:59.000Z

    In the present work we consider the effect of trapping as a microscopic process in a plasma consisting of quantum electrons and nondegenerate ions. The formation of solitary structures is investigated in two cases: first when the electrons are fully degenerate and second when small temperature effects are taken into account. It is seen that not only rarefactive but coupled rarefactive and compressive solitons are obtained under different temperature conditions.

  2. Can Neutrinos be Degenerate in Mass?

    E-Print Network [OSTI]

    John Ellis; Smaragda Lola

    1999-04-13T23:59:59.000Z

    We reconsider the possibility that the masses of the three light neutrinos of the Standard Model might be almost degenerate and close to the present upper limits from Tritium beta decay and cosmology. In such a scenario, the cancellations required by the latest upper limit on neutrinoless double-beta decay enforce near-maximal mixing that may be compatible only with the vacuum-oscillation scenario for solar neutrinos. We argue that the mixing angles yielded by degenerate neutrino mass-matrix textures are not in general stable under small perturbations. We evaluate within the MSSM the generation-dependent one-loop renormalization of neutrino mass-matrix textures that yielded degenerate masses and large mixing at the tree level. We find that m_{nu_e} > m_{nu_mu} > m_{nu_tau} after renormalization, excluding MSW effects on solar neutrinos. We verify that bimaximal mixing is not stable, and show that the renormalized masses and mixing angles are not compatible with all the experimental constraints, even for tanbeta as low as unity. These results hold whether the neutrino masses are generated by a see-saw mechanism with heavy neutrinos weighing approx. 10^{13} GeV or by non-renormalizable interactions at a scale approx. 10^5 GeV. We also comment on the corresponding renormalization effects in the minimal Standard Model, in which m_{nu_e} < m_{nu_mu} < m_{nu_tau}. Although a solar MSW effect is now possible, the perturbed neutrino masses and mixings are still not compatible with atmospheric- and solar-neutrino data.

  3. Affine and degenerate affine BMW algebras: Actions on tensor space

    E-Print Network [OSTI]

    Daugherty, Zajj; Virk, Rahbar

    2012-01-01T23:59:59.000Z

    The affine and degenerate affine Birman-Murakami-Wenzl (BMW) algebras arise naturally in the context of Schur-Weyl duality for orthogonal and symplectic quantum groups and Lie algebras, respectively. Cyclotomic BMW algebras, affine and cyclotomic Hecke algebras, and their degenerate versions are quotients. In this paper we explain how the affine and degenerate affine BMW algebras are tantalizers (tensor power centralizer algebras) by defining actions of the affine braid group and the degenerate affine braid algebra on tensor space and showing that, in important cases, these actions induce actions of the affine and degenerate affine BMW algebras. We then exploit the connection to quantum groups and Lie algebras to determine universal parameters for the affine and degenerate affine BMW algebras. Finally, we show that the universal parameters are central elements--the higher Casimir elements for orthogonal and symplectic enveloping algebras and quantum groups.

  4. Affine and degenerate affine BMW algebras: The center

    E-Print Network [OSTI]

    Daugherty, Zajj; Virk, Rahbar

    2011-01-01T23:59:59.000Z

    The degenerate affine and affine BMW algebras arise naturally in the context of Schur-Weyl duality for orthogonal and symplectic Lie algebras and quantum groups, respectively. Cyclotomic BMW algebras, affine Hecke algebras, cyclotomic Hecke algebras, and their degenerate versions are quotients. In this paper the theory is unified by treating the orthogonal and symplectic cases simultaneously; we make an exact parallel between the degenerate affine and affine cases via a new algebra which takes the role of the affine braid group for the degenerate setting. A main result of this paper is an identification of the centers of the affine and degenerate affine BMW algebras in terms of rings of symmetric functions which satisfy a "cancellation property" or "wheel condition" (in the degenerate case, a reformulation of a result of Nazarov). Miraculously, these same rings also arise in Schubert calculus, as the cohomology and K-theory of isotropic Grassmanians and symplectic loop Grassmanians. We also establish new inte...

  5. Relativistic Bernstein waves in a degenerate plasma

    SciTech Connect (OSTI)

    Ali, Muddasir; Hussain, Azhar [Department of Physics, G.C. University, Lahore 54000 (Pakistan); Salam Chair in Physics, G.C. University, Lahore 54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, G.C. University, Lahore 54000 (Pakistan)

    2011-09-15T23:59:59.000Z

    Bernstein mode for a relativistic degenerate electron plasma is investigated. Using relativistic Vlasov-Maxwell equations, a general expression for the conductivity tensor is derived and then employing Fermi-Dirac distribution function a generalized dispersion relation for the Bernstein mode is obtained. Two limiting cases, i.e., non-relativistic and ultra-relativistic are discussed. The dispersion relations obtained are also graphically presented for some specific values of the parameters depicting how the propagation characteristics of Bernstein waves as well as the Upper Hybrid oscillations are modified with the increase in plasma number density.

  6. Landau Diamagnetism of Degenerate Collisional Plasma

    E-Print Network [OSTI]

    A. V. Latyshev; A. A. Yushkanov

    2010-07-05T23:59:59.000Z

    For the first time the kinetic description of Landau diamagnetism for degenerate collisional plasma is given. The correct expression for transverse electric conductivity of the quantum plasma, found by authors (see arXiv:1002.1017 [math-ph] 4 Feb 2010) is used. In work S. Dattagupta, A.M. Jayannavar and N. Kumar [Current science, V. 80, No. 7, 10 April, 2001] was discussed the important problem of dissipation (collisions) influence on Landau diamagnetism. The analysis of this problem is given with the use of exact expression for transverse conductivity of quantum plasma.

  7. Tools for primal degenerate linear programs: IPS, DCA, and PE

    E-Print Network [OSTI]

    Jean-Bertrand Gauthier

    2014-10-08T23:59:59.000Z

    Oct 8, 2014 ... Tools for primal degenerate linear programs: IPS, DCA, and PE. Jean-Bertrand Gauthier(jean-bertrand.gauthier ***at*** hec.ca) Jacques ...

  8. Variational functions in degenerate open quantum systems

    SciTech Connect (OSTI)

    Jakob, Matthias; Stenholm, Stig [Laser Physics and Quantum Optics, Royal Institute of Technology (KTH), Alba Nova, Roslagstullsbacken 21, SE-10691 Stockholm (Sweden)

    2004-04-01T23:59:59.000Z

    We have derived a Lyapunov functional for a degenerate open atomic system. This functional develops monotonically towards its stationary state. The open system is described by a Lindblad-type master equation. For the construction of the variational functional it is necessary that the Lindblad operator can be diagonalized. Since the generator of motion is non-Hermitian, diagonalization is, in general, only possible if the eigenvalues are nondegenerate. In this paper, we propose that in a physical system the biorthogonal eigenbasis of the Lindblad operator remains complete even when degeneracy is present. Thus diagonalization of the Lindblad operator, and consequently the construction of the variational functional, is still possible. We discuss the reasons and illustrate the theory of the variational functional for a driven {lambda}-type three-level atom with degenerate ground state. The degeneracy has interesting effects on the variational functional in the steady state with respect to its interpretation as an entropic quantity. In case of the driven three-level atom, the dark state turns out to be an isentropic state.

  9. Thermodynamic functions of degenerate magnetized electron gas

    SciTech Connect (OSTI)

    Skobelev, V. V., E-mail: v.skobelev@inbox.ru [Moscow State Industrial University (Russian Federation)

    2011-11-15T23:59:59.000Z

    The Fermi energy, pressure, internal energy, entropy, and heat capacity of completely degenerate relativistic electron gas are calculated by numerical methods. It is shown that the maximum admissible magnetic field on the order of 10{sup 9} G in white dwarfs increases the pressure by a factor of 1.06 in the central region, where the electron concentration is {approx}10{sup 33} cm{sup -3}, while the equilibrium radius increases by approximately a factor of 1.03, which obviously cannot be observed experimentally. A magnetic field of {approx}10{sup 8} G or lower has no effect on the pressure and other thermodynamic functions. It is also shown that the contribution of degenerate electron gas to the total pressure in neutron stars is negligible compared to that of neutron gas even in magnetic fields with a maximum induction {approx}10{sup 17} G possible in neutron stars. The neutron beta-decay forbiddeness conditions in a superstrong magnetic field are formulated. It is assumed that small neutron stars have such magnetic fields and that pulsars with small periods are the most probable objects that can have super-strong magnetic fields.

  10. Emotion Regulation Deficits in Frontotemporal Lobar Degeneration and Alzheimer's Disease

    E-Print Network [OSTI]

    Levenson, Robert W.

    Emotion Regulation Deficits in Frontotemporal Lobar Degeneration and Alzheimer's Disease Madeleine instructed and spontaneous emotion regulation in patients with frontotemporal lobar degeneration (FTLD, N 32) unwarned without instructions to down-regulate, (b) warned without instructions to down-regulate, and (c

  11. VISCOSITY SOLUTIONS TO DEGENERATE COMPLEX MONGE-AMP`ERE EQUATIONS

    E-Print Network [OSTI]

    Boyer, Edmond

    VISCOSITY SOLUTIONS TO DEGENERATE COMPLEX MONGE-AMP`ERE EQUATIONS PHILIPPE EYSSIDIEUX, VINCENT an alternative approach based on the concept of viscosity solutions and compare systematically viscosity concepts PDE approach to second-order degenerate elliptic equations is the method of viscosity solutions

  12. Polarization degenerate solid-state cavity QED

    E-Print Network [OSTI]

    Morten P. Bakker; Ajit V. Barve; Thomas Ruytenberg; Wolfgang Loffler; Larry A. Coldren; Dirk Bouwmeester; Martin P. van Exter

    2015-03-27T23:59:59.000Z

    A polarization degenerate microcavity containing charge-controlled quantum dots (QDs) enables equal coupling of all polarization degrees of freedom of light to the cavity QED system, which we explore through resonant laser spectroscopy. We first measure interference of the two fine-split neutral QD transitions and find very good agreement of this V-type three-level system with a coherent polarization dependent cavity QED model. We also study a charged QD that suffers from decoherence, and find also in this case that availability of the full polarization degrees of freedom is crucial to reveal the dynamics of the QD transitions. Our results pave the way for postselection-free quantum devices based on electron spin-photon polarization entanglement.

  13. Single-Degenerate Type Ia Supernovae Are Preferentially Overluminous

    E-Print Network [OSTI]

    Fisher, Robert

    2015-01-01T23:59:59.000Z

    Recent observational and theoretical progress has favored merging and helium-accreting sub-Chandrasekhar mass white dwarfs in the double-degenerate and the double-detonation channels, respectively, as the most promising progenitors of normal Type Ia supernovae (SNe Ia). Thus the fate of rapidly-accreting Chandrasekhar mass white dwarfs in the single-degenerate channel remains more mysterious then ever. In this paper, we clarify the nature of ignition in Chandrasekhar-mass single-degenerate SNe Ia by analytically deriving the existence of a characteristic length scale which establishes a transition from central ignitions to buoyancy-driven ignitions. Using this criterion, combined with data from three-dimensional simulations of convection and ignition, we demonstrate that the overwhelming majority of ignition events within Chandrasekhar-mass white dwarfs in the single-degenerate channel are buoyancy-driven, and consequently lack a vigorous deflagration phase. We thus infer that single-degenerate SNe Ia are gen...

  14. Anomalous skin effects in a weakly magnetized degenerate electron plasma

    SciTech Connect (OSTI)

    Abbas, G., E-mail: gohar.abbas@gcu.edu.pk; Sarfraz, M. [Department of Physics, GC University Lahore, Katchery Road, Lahore 54000 (Pakistan); Shah, H. A. [Forman Christian College University, Farozpur Road, Lahore 54600 (Pakistan)

    2014-09-15T23:59:59.000Z

    Fully relativistic analysis of anomalous skin effects for parallel propagating waves in a weakly magnetized degenerate electron plasma is presented and a graphical comparison is made with the results obtained using relativistic Maxwellian distribution function [G. Abbas, M. F. Bashir, and G. Murtaza, Phys. Plasmas 18, 102115 (2011)]. It is found that the penetration depth for R- and L-waves for degenerate case is qualitatively small in comparison with the Maxwellian plasma case. The quantitative reduction due to weak magnetic field in the skin depth in R-wave for degenerate plasma is large as compared to the non-degenerate one. By ignoring the ambient magnetic field, previous results for degenerate field free case are salvaged [A. F. Alexandrov, A. S. Bogdankevich, and A. A. Rukhadze, Principles of Plasma Electrodynamics (Springer-Verlag, Berlin/Heidelberg, 1984), p. 90].

  15. Quantum weak chaos in a degenerate system

    E-Print Network [OSTI]

    V. Ya. Demikhovskii; D. I. Kamenev; G. A. Luna-Acosta

    1998-09-27T23:59:59.000Z

    Quantum weak chaos is studied in a perturbed degenerate system --- a charged particle interacting with a monochromatic wave in a transverse magnetic field. The evolution operator for an arbitrary number of periods of the external field is built and its structure is explored in terms of the QE (quasienergy eigenstates) under resonance condition (wave frequency $=$ cyclotron frequency) in the regime of weak classical chaos. The new phenomenon of diffusion via the quantum separatrices and the influence of chaos on diffusion are investigated and, in the quasi classical limit, compared with its classical dynamics. We determine the crossover from purely quantum diffusion to a diffusion which is the quantum manifestation of classical diffusion along the stochastic web. This crossover results from the non-monotonic dependence of the characteristic localization length of the QE states on the wave amplitude. The width of the quantum separatrices was computed and compared with the width of the classical stochastic web. We give the physical parameters which can be realized experimentally to show the manifestation of quantum chaos in nonlinear acoustic resonance.

  16. A FINITE DIFFERENCE APPROACH TO DEGENERATE BERNOULLI AND STIRLING POLYNOMIALS

    E-Print Network [OSTI]

    Adelberg, Arnold

    A FINITE DIFFERENCE APPROACH TO DEGENERATE BERNOULLI AND STIRLING POLYNOMIALS Arnold Adelberg, 1992 1 #12; RUNNING HEAD: Degen Bernoulli/Stirling Pols Professor Arnold Adelberg Department parameters), which includes Bernoulli and Stirling polynomials and various generalizations, is developed

  17. Healthy Eyes Bulletin Your Eyes Are the Windows to Your Health.

    E-Print Network [OSTI]

    Baker, Chris I.

    to an increased risk of developing age-related macular degeneration,cataract,and optic nerve damage,all of which signs of damage or disease. Your eye care professional is the only one who can determine if your eyes,look for ones that block out 99 to 100 percent of both UV-A and UV-B radiation. Give your eyes a rest.If you

  18. Gell-Mann and Low formula for degenerate unperturbed states

    E-Print Network [OSTI]

    Christian Brouder; Gianluca Panati; Gabriel Stoltz

    2009-12-08T23:59:59.000Z

    The Gell-Mann and Low switching allows to transform eigenstates of an unperturbed Hamiltonian $H_0$ into eigenstates of the modified Hamiltonian $H_0 + V$. This switching can be performed when the initial eigenstate is not degenerate, under some gap conditions with the remainder of the spectrum. We show here how to extend this approach to the case when the ground state of the unperturbed Hamiltonian is degenerate. More precisely, we prove that the switching procedure can still be performed when the initial states are eigenstates of the finite rank self-adjoint operator $\\cP_0 V \\cP_0$, where $\\cP_0$ is the projection onto a degenerate eigenspace of $H_0$.

  19. Loss of Daylight Vision in Retinal Degeneration: Are

    E-Print Network [OSTI]

    Tabin, Cliff

    Loss of Daylight Vision in Retinal Degeneration: Are Oxidative Stress and Metabolic Dysregulation, particularly in cones, the type of photoreceptors that mediate daylight and color vision. The evidence, providing our daylight vision, and have many of the same features and vulnerabilities as rod photoreceptors

  20. Degenerate band edges in optical fiber with multiple

    E-Print Network [OSTI]

    the forward energy fluxes S of the two media defines the coupling efficiency ¼ S2=S1. For PBG materialsDegenerate band edges in optical fiber with multiple grating: efficient coupling to slow light), School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia 2 CUDOS, School

  1. Mss. 12 December 2013 DEGENERATIONS OF IRRATIONAL TORIC VARIETIES

    E-Print Network [OSTI]

    Sottile, Frank

    .XA for w RA > gives an identification between limiting positions of positive torus translations of XA to a finite configuration of real vectors. The positive torus acts on X by translation, and we consider limits toric variety, toric degeneration. This material is based on work done while Postinghel and Sottile were

  2. Blood Flow Magnetic Resonance Imaging of Retinal Degeneration

    E-Print Network [OSTI]

    Duong, Timothy Q.

    Blood Flow Magnetic Resonance Imaging of Retinal Degeneration Yingxia Li,1 Haiying Cheng,1 Qiang. Duong1,2,3,4,5,6,7 PURPOSE. This study aims to investigate quantitative basal blood flow as well as hypercapnia- and hyperoxia-induced blood flow changes in the retinas of the Royal College of Surgeons (RCS

  3. Linear harmonic oscillator in spaces with degenerate metrics

    E-Print Network [OSTI]

    N. A. Gromov

    2006-03-02T23:59:59.000Z

    With the help of contraction method we study the harmonic oscillator in spaces with degenerate metrics, namely, on Galilei plane and in the flat 3D Cayley-Klein spaces $R_3(j_2,j_3).$ It is shown that the inner degrees of freedom are appeared which physical dimensions are different from the dimension of the space.

  4. A New Merging Double Degenerate Binary in the Solar Neighborhood

    E-Print Network [OSTI]

    Debes, John H; Tremblay, Pier-Emmanuel; López-Morales, Mercedes; Anglada-Escudé, Guillem; Napiwotzki, Ralf; Osip, David; Weinberger, Alycia

    2015-01-01T23:59:59.000Z

    Characterizing the local space density of double degenerate binary systems is a complementary approach to broad sky surveys of double degenerates to determine the expected rates of white dwarf binary mergers, in particular those that may evolve into other observable phenomena such as extreme helium stars, Am CVn systems, and supernovae Ia. However, there have been few such systems detected in local space. We report here the discovery that WD 1242$-$105, a nearby bright WD, is a double-line spectroscopic binary consisting of two degenerate DA white dwarfs of similar mass and temperature, despite it previously having been spectroscopically characterized as a single degenerate. Follow-up photometry, spectroscopy, and trigonometric parallax have been obtained in an effort to determine the fundamental parameters of each component of this system. The binary has a mass ratio of 0.7 and a trigonometric parallax of 25.5 mas, placing it at a distance of 39 pc. The system's total mass is 0.95 M$_\\odot$ and has an orbita...

  5. Remarks on Cyclotomic and Degenerate Cyclotomic BMW Algebras

    E-Print Network [OSTI]

    Goodman, Frederick M

    2010-01-01T23:59:59.000Z

    We relate the structure of cyclotomic and degenerate cyclotomic BMW algebras, for arbitrary parameter values, to that for admissible parameter values. In particular, we show that these algebras are cellular. We characterize those parameter sets for affine BMW algebras over an algebraically closed field that permit the algebras to have non--trivial cyclotomic quotients.

  6. Automatic Diabetic Macular Edema Detection in Fundus Images Using Publicly Available Datasets

    SciTech Connect (OSTI)

    Giancardo, Luca [ORNL; Meriaudeau, Fabrice [ORNL; Karnowski, Thomas Paul [ORNL; Li, Yaquin [University of Tennessee, Knoxville (UTK); Garg, Seema [University of North Carolina; Tobin Jr, Kenneth William [ORNL; Chaum, Edward [University of Tennessee, Knoxville (UTK)

    2011-01-01T23:59:59.000Z

    Diabetic macular edema (DME) is a common vision threatening complication of diabetic retinopathy. In a large scale screening environment DME can be assessed by detecting exudates (a type of bright lesions) in fundus images. In this work, we introduce a new methodology for diagnosis of DME using a novel set of features based on colour, wavelet decomposition and automatic lesion segmentation. These features are employed to train a classifier able to automatically diagnose DME. We present a new publicly available dataset with ground-truth data containing 169 patients from various ethnic groups and levels of DME. This and other two publicly available datasets are employed to evaluate our algorithm. We are able to achieve diagnosis performance comparable to retina experts on the MESSIDOR (an independently labelled dataset with 1200 images) with cross-dataset testing. Our algorithm is robust to segmentation uncertainties, does not need ground truth at lesion level, and is very fast, generating a diagnosis on an average of 4.4 seconds per image on an 2.6 GHz platform with an unoptimised Matlab implementation.

  7. Electron thermal conductivity owing to collisions between degenerate electrons

    E-Print Network [OSTI]

    P. S. Shternin; D. G. Yakovlev

    2006-08-17T23:59:59.000Z

    We calculate the thermal conductivity of electrons produced by electron-electron Coulomb scattering in a strongly degenerate electron gas taking into account the Landau damping of transverse plasmons. The Landau damping strongly reduces this conductivity in the domain of ultrarelativistic electrons at temperatures below the electron plasma temperature. In the inner crust of a neutron star at temperatures T scattering and becomes competitive with the the electron conductivity due to scattering of electrons by impurity ions.

  8. Quasi-Degenerate Neutrino Masses with Normal and Inverted Hierarchy

    E-Print Network [OSTI]

    Francis, Ng K

    2012-01-01T23:59:59.000Z

    The effects of CP-phases on the three absolute quasi-degenerate Majorana neutrino (QDN) masses are stud-ied with neutrino mass matrices obeying {\\mu} - {\\tau} symmetry for normal as well as inverted hierarchical mass patterns. We have made further investigations on 1) the prediction of solar mixing angle which lies below tri-bimaximal mixing value in consistent with neutrino oscillation observational data, 2) the prediction on absolute neutrino mass parameter (mee) in 0{\

  9. Electrostatic rogue-waves in relativistically degenerate plasmas

    SciTech Connect (OSTI)

    Akbari-Moghanjoughi, M. [Department of Physics, Faculty of Sciences, Azarbaijan Shahid Madani University, 51745-406 Tabriz, Iran and International Centre for Advanced Studies in Physical Sciences and Institute for Theoretical Physics, Ruhr University Bochum, D-44780 Bochum (Germany)

    2014-10-15T23:59:59.000Z

    In this paper, we investigate the modulational instability and the possibility of electrostatic rogue-wave propagations in a completely degenerate plasma with arbitrary degree of degeneracy, i.e., relativistically degenerate plasma, ranging from solid density to the astrophysical compact stars. The hydrodynamic approach along with the perturbation method is used to reduce the governing equations to the nonlinear Schrödinger equation from which the modulational instability, the growth rate of envelope excitations and the occurrence of rogue as well as super-rogue waves in the plasma, is evaluated. It is observed that the modulational instability in a fully degenerate plasma can be quite sensitive to the plasma number-density and the wavenumber of envelop excitations. It is further revealed that the relativistically degeneracy plasmas (R{sub 0}?>?1) are almost always modulationally unstable. It is found, however, that the highly energetic sharply localized electrostatic rogue as well as super-rogue waves can exist in the astrophysical compact objects like white dwarfs and neutron star crusts. The later may provide a link to understand many physical processes in such stars and it may lead us to the origin of the random-localized intense short gamma-ray bursts, which “appear from nowhere and disappear without a trace” quite similar to oceanic rogue structures.

  10. Wallerian degeneration demonstrated by magnetic resonance: spectroscopic measurements on peripheral nerve. [Rats

    SciTech Connect (OSTI)

    Jolesz, F.A.; Polak, J.F.; Ruenzel, P.W.; Adams, D.F.

    1984-07-01T23:59:59.000Z

    Wallerian degeneration of rat sciatic nerves was induced by nerve section. Fifteen days later the degenerated nerves were compared with the intact contralteral nerves from the same animal. Histological sections showed the changes typical of wallerian degeneration: axonal degeneration and secondary demyelination. The freshly dissected nerves were analyzed by magnetic resonance (MR) spectroscopy at 10 MHz, and the water content was determined by dehydration. In the degenerated nerves there was a marked prolongation of both T1 and T2 relaxation times, accompanied by an increase of water content. These results suggest that it should be possible to detect wallerian degeneration in MR images; this will have an important impact on neuropathological diagnosis of central and peripheral nervous system lesions.

  11. Imploding and exploding shocks in negative ion degenerate plasmas

    SciTech Connect (OSTI)

    Hussain, S.; Akhtar, N. [Theoretical Plasma Physics Division, PINSTECH, Nilore, Islamabad 44000 (Pakistan); Department of Physics and Applied Mathematics PIEAS, Nilore, Islamabad 44000 (Pakistan)

    2011-08-15T23:59:59.000Z

    Imploding and exploding shocks are studied in nonplanar geometries for negative ion degenerate plasma. Deformed Korteweg de Vries Burgers (DKdVB) equation is derived by using reductive perturbation method. Two level finite difference scheme is used for numerical analysis of DKdVB. It is observed that compressive and rarefactive shocks are observed depending on the value of quantum parameter. The effects of temperature, kinematic viscosity, mass ratio of negative to positive ions and quantum parameter on diverging and converging shocks are presented.

  12. Remarkable Degenerate Quantum Stabilizer Codes Derived from Duadic Codes

    E-Print Network [OSTI]

    Salah A. Aly; Andreas Klappenecker; Pradeep Kiran Sarvepalli

    2006-01-18T23:59:59.000Z

    Good quantum codes, such as quantum MDS codes, are typically nondegenerate, meaning that errors of small weight require active error-correction, which is--paradoxically--itself prone to errors. Decoherence free subspaces, on the other hand, do not require active error correction, but perform poorly in terms of minimum distance. In this paper, examples of degenerate quantum codes are constructed that have better minimum distance than decoherence free subspaces and allow some errors of small weight that do not require active error correction. In particular, two new families of [[n,1,>= sqrt(n)

  13. Role of degeneration processes in picosecond nonlinear spectroscopy of HTSCs

    SciTech Connect (OSTI)

    Bobyrev, Yu V; Petnikova, V M; Rudenko, K V; Shuvalov, Vladimir V [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2005-11-30T23:59:59.000Z

    It is shown that both spectral-temporal and temperature anomalies of the reflectance and transmittance kinetics of high-temperature superconducting films at high 'impact' excitation levels have a direct analogue in the case when much longer and coincident in time picosecond pulses are used to excite and probe the film state. In this case, due to degeneration, the nontrivial (with a sharp jump in the vicinity of the phase transition point) dependence of the nonlinear response amplitude of a sample on its initial temperature should be observed. (nonlinear optical phenomena)

  14. Three dimensional electrostatic solitary waves in a dense magnetoplasma with relativistically degenerate electrons

    SciTech Connect (OSTI)

    Ata-ur-Rahman,; Qamar, A. [Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan) [Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan); National Centre for Physics, QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan); Masood, W. [National Centre for Physics, QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan) [National Centre for Physics, QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan); COMSATS, Institute of Information Technology, Park Road, Chak Shahzad, Islamabad 44000 (Pakistan); Eliasson, B. [Physics Department, University of Strathclyde, Glasgow G4 0NG, Scotland (United Kingdom)] [Physics Department, University of Strathclyde, Glasgow G4 0NG, Scotland (United Kingdom)

    2013-09-15T23:59:59.000Z

    In this paper, small but finite amplitude electrostatic solitary waves in a relativistic degenerate magnetoplasma, consisting of relativistically degenerate electrons and non-degenerate cold ions, are investigated. The Zakharov-Kuznetsov equation is derived employing the reductive perturbation technique and its solitary wave solution is analyzed. It is shown that only compressive electrostatic solitary structures can propagate in such a degenerate plasma system. The effects of plasma number density, ion cyclotron frequency, and direction cosines on the profiles of ion acoustic solitary waves are investigated and discussed at length. The relevance of the present investigation vis-a-vis pulsating white dwarfs is also pointed out.

  15. Coupled modes in magnetized dense plasma with relativistic-degenerate electrons

    SciTech Connect (OSTI)

    Khan, S. A. [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan)

    2012-01-15T23:59:59.000Z

    Low frequency electrostatic and electromagnetic waves are investigated in ultra-dense quantum magnetoplasma with relativistic-degenerate electron and non-degenerate ion fluids. The dispersion relation is derived for mobile as well as immobile ions by employing hydrodynamic equations for such plasma under the influence of electromagnetic forces and pressure gradient of relativistic-degenerate Fermi gas of electrons. The result shows the coexistence of shear Alfven and ion modes with relativistically modified dispersive properties. The relevance of results to the dense degenerate plasmas of astrophysical origin (for instance, white dwarf stars) is pointed out with brief discussion on ultra-relativistic and non-relativistic limits.

  16. Perpendicular propagating modes for weakly magnetized relativistic degenerate plasma

    SciTech Connect (OSTI)

    Abbas, Gohar; Bashir, M. F. [Salam Chair in Physics, G. C. University Lahore, Punjab 54000 (Pakistan); Department of Physics, G. C. University Lahore, Punjab 54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, G. C. University Lahore, Punjab 54000 (Pakistan)

    2012-07-15T23:59:59.000Z

    Using the Vlasov-Maxwell system of equations, the dispersion relations for the perpendicular propagating modes (i.e., X-mode, O-mode, and upper hybrid mode) are derived for a weakly magnetized relativistic degenerate electron plasma. By using the density (n{sub 0}=p{sub F}{sup 3}/3{pi}{sup 2} Planck-Constant-Over-Two-Pi {sup 3}) and the magnetic field values for different relativistic degenerate environments, the propagation characteristics (i.e., cutoff points, resonances, dispersions, and band widths in k-space) of these modes are examined. It is observed that the relativistic effects suppress the effect of ambient magnetic field and therefore the cutoff and resonance points shift towards the lower frequency regime resulting in enhancement of the propagation domain. The dispersion relations of these modes for the non-relativistic limit (p{sub F}{sup 2} Much-Less-Than m{sub 0}{sup 2}c{sup 2}) and the ultra-relativistic limit (p{sub F}{sup 2} Much-Greater-Than m{sub 0}{sup 2}c{sup 2}) are also presented.

  17. Dwarf spheroidal galaxies as degenerate gas of free fermions

    E-Print Network [OSTI]

    Valerie Domcke; Alfredo Urbano

    2014-12-16T23:59:59.000Z

    In this paper we analyze a simple scenario in which Dark Matter (DM) consists of free fermions with mass $m_f$. We assume that on galactic scales these fermions are capable of forming a degenerate Fermi gas, in which stability against gravitational collapse is ensured by the Pauli exclusion principle. The mass density of the resulting configuration is governed by a non-relativistic Lane-Emden equation, thus leading to a universal cored profile that depends only on one free parameter in addition to $m_f$. After reviewing the basic formalism, we test this scenario against experimental data describing the velocity dispersion of the eight classical dwarf spheroidal galaxies of the Milky Way. We find that, despite its extreme simplicity, the model exhibits a good fit to the data and realistic predictions for the size of DM halos providing that $m_f\\simeq 200$ eV. Furthermore, we show that in this setup larger galaxies correspond to the non-degenerate limit of the gas. We propose a concrete realization of this model in which DM is produced non-thermally via inflaton decay. We show that imposing the correct relic abundance and the bound on the free-streaming length constrains the inflation model in terms of inflaton mass, its branching ratio into DM and the reheating temperature.

  18. Degenerate U-and V -statistics under ergodicity: Asymptotics, bootstrap and applications in statistics

    E-Print Network [OSTI]

    Degenerate U- and V -statistics under ergodicity: Asymptotics, bootstrap and applications in statistics Anne Leucht Universit¨at Hamburg Fachbereich Mathematik, SPST Bundesstra�e 55 D-20146 Hamburg.neumann@uni-jena.de Abstract We derive the asymptotic distributions of degenerate U- and V -statistics of stationary

  19. Study of the cyclicity of some degenerate graphics inside quadratic systems

    E-Print Network [OSTI]

    Rousseau, Christiane

    Study of the cyclicity of some degenerate graphics inside quadratic systems F. Dumortier, Hasselt make essential steps in proving the finite cyclicity of degenerate graphics in quadratic systems, having a line of singular points in the finite plane. In particular we consider the graphics (DF1a), (DF2

  20. A Distributed Simplex Algorithm for Degenerate Linear Programs and Multi-Agent Assignments

    E-Print Network [OSTI]

    Bullo, Francesco

    A Distributed Simplex Algorithm for Degenerate Linear Programs and Multi-Agent Assignments Mathias: Distributed Simplex, Distributed Linear Programming, Asynchronous Algorithm, Multi-Agent Task Assignment. M we propose a novel distributed algorithm to solve degenerate linear programs on asynchronous peer

  1. Monte Carlo simulation of electron transport in degenerate and inhomogeneous semiconductors

    E-Print Network [OSTI]

    Monte Carlo simulation of electron transport in degenerate and inhomogeneous semiconductors Mona concentrations up to 1020 cm-3 . De- generate semiconductors are important for thermoelectric and thermionic transport in degenerate semiconductor-based structures. If the electron wavelength is smaller than

  2. Magnetohydrodynamic spin waves in degenerate electron-positron-ion plasmas

    SciTech Connect (OSTI)

    Mushtaq, A. [TPPD, PINSTECH Nilore, 44000 Islamabad (Pakistan); National Center for Physics, Shahdrah Valley Road, 44000 Islamabad (Pakistan); Maroof, R.; Ahmad, Zulfiaqr [Institute of Physics and Electronics, University of Peshawar, 25000 Peshawar (Pakistan); Qamar, A. [National Center for Physics, Shahdrah Valley Road, 44000 Islamabad (Pakistan); Institute of Physics and Electronics, University of Peshawar, 25000 Peshawar (Pakistan)

    2012-05-15T23:59:59.000Z

    Low frequency magnetosonic waves are studied in magnetized degenerate electron-positron-ion plasmas with spin effects. Using the fluid equations of magnetoplasma with quantum corrections due to the Bohm potential, temperature degeneracy, and spin magnetization energy, a generalized dispersion relation for oblique magnetosonic waves is derived. Spin effects are incorporated via spin force and macroscopic spin magnetization current. For three different values of angle {theta}, the generalized dispersion relation is reduced to three different relations under the low frequency magnetohydrodynamic assumptions. It is found that the effect of quantum corrections in the presence of positron concentration significantly modifies the dispersive properties of these modes. The importance of the work relevant to compact astrophysical bodies is pointed out.

  3. Phase conjugation by degenerate forward four-wave mixing

    SciTech Connect (OSTI)

    Khyzniak, A.; Kondilenko, V.; Kucherov, Iu.; Lesnik, S.; Odoulov, S.; Soskin, M.

    1984-02-01T23:59:59.000Z

    Phase conjugation (PC) that is due to degenerate forward four-wave mixing is studied both theoretically and experimentally. Similarity to backward four-wave mixing, the limiting efficiency of this process corresponds to the total energy transfer from each pump wave into the signal and conjugate waves, although in this case the Yariv oscillations do not occur. The numerical solution of the nonstationary problem is presented, revealing the transient oscillations of the PC-beam intensity with maxima many times exceeding the saturation value. PC of Q-switched and free-oscillating solid-state laser radiation is obtained by using the thermal nonlinearity of absorbing solutions. PC of CW laser radiation is obtained in a LiNbO3 crystal, the PC-beam intensity being six times larger than the initial intensity of the signal beam. The self-compensation of nonlinear phase distortions of the recording medium is demonstrated. 33 references.

  4. Harmonic entanglement in a degenerate parametric down conversion

    E-Print Network [OSTI]

    Sintayehu Tesfa

    2007-07-25T23:59:59.000Z

    We study the harmonic entanglement and squeezing in a two-mode radiation produced in a degenerate parametric down conversion process coupled to a two-mode vacuum reservoir employing the linearization procedure. It is found that there is a quadrature entanglement between the harmonically related fundamental and second-harmonic modes and the superimposed radiation exhibits a significant two-mode squeezing. The entanglement exits even when there is no two-mode squeezing, since the correlation leading to these phenomena are essentially different. In addition, the more the external coherent light is down converted, the more stronger the entanglement and mean photon number of the two-mode radiation would be which is not generally true for squeezing.

  5. Frozen light in photonic crystals with degenerate band edge

    E-Print Network [OSTI]

    A. Figotin; I. Vitebskiy

    2006-10-09T23:59:59.000Z

    Consider a plane monochromatic wave incident on a semi-infinite periodic structure. What happens if the normal component of the transmitted wave group velocity vanishes? At first sight, zero normal component of the transmitted wave group velocity simply implies total reflection of the incident wave. But we demonstrate that total reflection is not the only possible outcome. Instead, the transmitted wave can appear in the form of a frozen mode with very large diverging amplitude and either zero, or purely tangential energy flux. The field amplitude in the transmitted wave can exceed that of the incident wave by several orders of magnitude. There are two qualitatively different kinds of frozen mode regime. The first one is associated with a stationary inflection point of electromagnetic dispersion relation. This phenomenon has been analyzed in our previous publications. Now, our focus is on the frozen mode regime related to a degenerate photonic band edge. An advantage of this new phenomenon is that it can occur in much simpler periodic structures. This spectacular effect is extremely sensitive to the frequency and direction of propagation of the incident plane wave. These features can be very attractive in a variety practical applications, such as higher harmonic generation and wave mixing, light amplification and lasing, highly efficient superprizms, etc.

  6. Effect of trapping in a degenerate plasma in the presence of a quantizing magnetic field

    SciTech Connect (OSTI)

    Shah, H. A.; Iqbal, M. J.; Qureshi, M. N. S. [Department of Physics, GC University, Lahore 54000 (Pakistan); Tsintsadze, N. [Department of Physics, GC University, Lahore 54000 (Pakistan); Institute of Physics, Tbilisi 0177 (Georgia); Masood, W. [Theoretical Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan)

    2012-09-15T23:59:59.000Z

    Effect of trapping as a microscopic phenomenon in a degenerate plasma is investigated in the presence of a quantizing magnetic field. The plasma comprises degenerate electrons and non-degenerate ions. The presence of the quantizing magnetic field is discussed briefly and the effect of trapping is investigated by using the Fermi-Dirac distribution function. The linear dispersion relation for ion acoustic wave is derived in the presence of the quantizing magnetic field and its influence on the propagation characteristics of the linear ion acoustic wave is discussed. Subsequently, fully nonlinear equations for ion acoustic waves are used to obtain the Sagdeev potential and the investigation of solitary structures. The formation of solitary structures is studied both for fully and partially degenerate plasmas in the presence of a quantizing magnetic field. Both compressive and rarefactive solitons are obtained for different conditions of temperature and magnetic field.

  7. Natural guardians of the race: heredity, hygiene, alcohol, and degeneration in Scottish Psychiatry, c. 1860 – 1920 

    E-Print Network [OSTI]

    Wood, James Anthony

    2012-06-29T23:59:59.000Z

    This thesis investigates the ways in which hereditary degeneration was discussed by Scottish psychiatrists in the late nineteenth and early twentieth centuries with particular reference to the anti-alcohol debate. I ...

  8. Temperature jump in degenerate quantum gases in the presence of a Bose - Einstein condensate

    E-Print Network [OSTI]

    A. V. Latyshev; A. A. Yushkanov

    2010-01-04T23:59:59.000Z

    We construct a kinetic equation modeling the behavior of degenerate quantum Bose gases whose collision rate depends on the momentum of elementary excitations. We consider the case where the phonon component is the decisive factor in the elementary excitations. We analytically solve the half-space boundary value problem of the temperature jump at the boundary of the degenerate Bose gas in the presence of a Bose -- Einstein condensate.

  9. Genetic Studies of Complex Human Diseases: Characterizing SNP-Disease Associations Using Bayesian Networks

    E-Print Network [OSTI]

    Han, Bing; Chen, Xue-wen; Talebizadeh, Zohreh; Xu, Hua

    2012-12-17T23:59:59.000Z

    (Suppl 3):S14 http://www.biomedcentral.com/1752-0509/6/S3/S14 © 2012 Han et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2...) heuristic search method can solve the classical XOR (Exclusive or) pro- blem [14]. We apply the EpiBN method to simulated datasets based on four disease models and three real datasets: Age-related Macular Degeneration (AMD) dataset, late-onset Alzheimer...

  10. Nearly degenerate heavy sterile neutrinos in cascade decay: mixing and oscillations

    E-Print Network [OSTI]

    Boyanovsky, Daniel

    2014-01-01T23:59:59.000Z

    Some extensions beyond the Standard Model propose the existence of nearly degenerate heavy sterile neutrinos. If kinematically allowed these can be resonantly produced and decay in a cascade to common final states. The common decay channels lead to mixing of the heavy sterile neutrino states and interference effects. We implement non-perturbative methods to study the dynamics of the cascade decay to common final states, which features similarities but also noteworthy differences with the case of neutral meson mixing. We show that mixing and oscillations among the nearly degenerate sterile neutrinos can be detected as \\emph{quantum beats} in the distribution of final states produced from their decay. These oscillations would be a telltale signal of mixing between heavy sterile neutrinos. We study in detail the case of two nearly degenerate sterile neutrinos produced in the decay of pseudoscalar mesons and decaying into a purely leptonic "visible" channel: $\

  11. Nearly degenerate heavy sterile neutrinos in cascade decay: mixing and oscillations

    E-Print Network [OSTI]

    Daniel Boyanovsky

    2014-11-20T23:59:59.000Z

    Some extensions beyond the Standard Model propose the existence of nearly degenerate heavy sterile neutrinos. If kinematically allowed these can be resonantly produced and decay in a cascade to common final states. The common decay channels lead to mixing of the heavy sterile neutrino states and interference effects. We implement non-perturbative methods to study the dynamics of the cascade decay to common final states, which features similarities but also noteworthy differences with the case of neutral meson mixing. We show that mixing and oscillations among the nearly degenerate sterile neutrinos can be detected as \\emph{quantum beats} in the distribution of final states produced from their decay. These oscillations would be a telltale signal of mixing between heavy sterile neutrinos. We study in detail the case of two nearly degenerate sterile neutrinos produced in the decay of pseudoscalar mesons and decaying into a purely leptonic "visible" channel: $\

  12. The effective density of randomly moving electrons and related characteristics of materials with degenerate electron gas

    SciTech Connect (OSTI)

    Palenskis, V., E-mail: vilius.palenskis@ff.vu.lt [Radiophysics Department, Faculty of Physics, Vilnius University, Saul?tekio al. 9, LT-10222, Vilnius (Lithuania)

    2014-04-15T23:59:59.000Z

    Interpretation of the conductivity of metals, of superconductors in the normal state and of semiconductors with highly degenerate electron gas remains a significant issue if consideration is based on the classical statistics. This study is addressed to the characterization of the effective density of randomly moving electrons and to the evaluation of carrier diffusion coefficient, mobility, and other parameters by generalization of the widely published experimental results. The generalized expressions have been derived for various kinetic parameters attributed to the non-degenerate and degenerate electron gas, by analyzing a random motion of the single type carriers in homogeneous materials. The values of the most important kinetic parameters for different metals are also systematized and discussed. It has been proved that Einstein's relation between the diffusion coefficient and the drift mobility of electrons is held for any level of degeneracy if the effective density of randomly moving carriers is properly taken into account.

  13. Dyakonov-perel electron spin relaxation in a highly degenerate wurtzite semiconductor

    SciTech Connect (OSTI)

    Rudolph, J.; Buß, J. H.; Hägele, D. [Arbeitsgruppe Spektroskopie der kondensierten Materie, Ruhr-Universität Bochum, Universitätsstraße 150, D-44780 Bochum (Germany); Semond, F. [Centre de Recherche sur l'Hétéro-Epitaxie et ses Applications, Centre National de la Recherche Scientifique, Sophia Antipolis, Valbonne (France)

    2013-12-04T23:59:59.000Z

    The doping density dependence of the electron spin lifetime in n-type bulk GaN is investigated up to the highly degenerate regime by time-resolved Kerr-rotation spectroscopy. We find a non-monotonic doping density dependence with maximum spin lifetimes at the onset of degeneracy. The reduction of spin lifetimes in the degenerate regime shows a weak ?{sub s}?n{sub D}{sup ?2/3} density dependence, in full agreement with Dyakonov-Perel theory.

  14. A nonlinear model for magnetoacoustic waves in dense dissipative plasmas with degenerate electrons

    SciTech Connect (OSTI)

    Masood, W. [COMSATS Institute of Information Technology, Islamabad (Pakistan); National Centre for Physics (NCP), Shahdra Valley Road, Islamabad (Pakistan); Jahangir, R.; Siddiq, M. [National Centre for Physics (NCP), Shahdra Valley Road, Islamabad (Pakistan); Eliasson, B. [SUPA, Physics Department, University of Strathclyde, Glasgow (United Kingdom)

    2014-10-15T23:59:59.000Z

    The properties of nonlinear fast magnetoacoustic waves in dense dissipative plasmas with degenerate electrons are studied theoretically in the framework of the Zabolotskaya-Khokhlov (ZK) equation for small but finite amplitude excitations. Shock-like solutions of the ZK equation are obtained and are applied to parameters relevant to white dwarf stars.

  15. Accelerator-based neutron source using a cold deuterium target with degenerate electrons

    SciTech Connect (OSTI)

    Phillips, R. E.; Ordonez, C. A. [Department of Physics, University of North Texas, Denton, Texas 76203 (United States)] [Department of Physics, University of North Texas, Denton, Texas 76203 (United States)

    2013-07-15T23:59:59.000Z

    A neutron generator is considered in which a beam of tritons is incident on a hypothetical cold deuterium target with degenerate electrons. The energy efficiency of neutron generation is found to increase substantially with electron density. Recent reports of potential targets are discussed.

  16. Interference of nonlinear response components in degenerate four-photon spectroscopy of ultrathin metal films

    SciTech Connect (OSTI)

    Bobyrev, Yu V; Petnikova, V M; Rudenko, K V; Shipova, A Yu; Shuvalov, Vladimir V [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2003-11-30T23:59:59.000Z

    It is shown that a specific dip in the spectral dependence of the nonlinear response of ultrathin metal films observed by the method of degenerate four-photon spectroscopy is caused by a change in the phases of interfering components of the electron nonlinear susceptibility. This allows one to measure the time scale of subpicosecond intraband processes using picosecond light pulses. (nonlinear optical phenomena)

  17. Progress in year 2010 1. Suppression of Density Fluctuations in a Quantum Degenerate Fermi

    E-Print Network [OSTI]

    Progress in year 2010 1. Suppression of Density Fluctuations in a Quantum Degenerate Fermi Gas with temperatures obtained by fitting the shape of the expanded cloud. 2. Spin gradient demagnetization cooling of ultracold atoms. We have demonstrated a new cooling method in which a time-varying magnetic field gradient

  18. Nonlinear electrostatic excitations in magnetized dense plasmas with nonrelativistic and ultra-relativistic degenerate electrons

    SciTech Connect (OSTI)

    Mahmood, S.; Sadiq, Safeer; Haque, Q. [Theoretical Physics Division (TPD), PINSTECH, P.O. Nilore, Islamabad 44000 (Pakistan)] [Theoretical Physics Division (TPD), PINSTECH, P.O. Nilore, Islamabad 44000 (Pakistan)

    2013-12-15T23:59:59.000Z

    Linear and nonlinear electrostatic waves in magnetized dense electron-ion plasmas are studied with nonrelativistic and ultra-relativistic degenerate and singly, doubly charged helium (He{sup +}, He{sup ++}) and hydrogen (H{sup +}) ions, respectively. The dispersion relation of electrostatic waves in magnetized dense plasmas is obtained under both the energy limits of degenerate electrons. Using reductive perturbation method, the Zakharov-Kuznetsov equation for nonlinear propagation of electrostatic solitons in magnetized dense plasmas is derived for both nonrelativistic and ultra-relativistic degenerate electrons. It is found that variations in plasma density, magnetic field intensity, different mass, and charge number of ions play significant role in the formation of electrostatic solitons in magnetized dense plasmas. The numerical plots are also presented for illustration using the parameters of dense astrophysical plasma situations such as white dwarfs and neutron stars exist in the literature. The present investigation is important for understanding the electrostatic waves propagation in the outer periphery of compact stars which mostly consists of hydrogen and helium ions with degenerate electrons in dense magnetized plasmas.

  19. MONOTONE DIFFERENCE SCHEMES STABILIZED BY DISCRETE MOLLIFICATION FOR STRONGLY DEGENERATE PARABOLIC EQUATIONS

    E-Print Network [OSTI]

    , 2009. AUniversidad Nacional de Colombia, Department of Mathematics and Statistics, Manizales, Colombia conservation law. Therefore, (1.1) is called strongly degenerate. It is well known that solutions of (1.1), (1-Mail: rburger@ing-mat.udec.cl. CUniversidad Nacional de Colombia, Department of Mathematics, Medell´in, Colombia

  20. Analytical model of electron transport in polycrystalline, degenerately doped ZnO films

    SciTech Connect (OSTI)

    Bikowski, André, E-mail: andre.bikowski@helmholtz-berlin.de; Ellmer, Klaus [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Institute for Solar Fuels, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany)

    2014-10-14T23:59:59.000Z

    An analytical description of the charge carrier transport, valid for non-degenerated and degenerated semiconductors, was developed, critically reviewed, and fitted to the temperature-dependent Hall mobility data of magnetron sputtered, degenerately doped ZnO:Al films. Our extended model for grain boundary scattering in semiconductors of arbitrary degeneracy is based on previous models from literature and suitable to describe the Hall mobility of the carriers as a function of the free carrier concentration and the temperature at the same time. It is mathematically simple enough for a fast fit procedure, which is not possible with most of the previous models. Applying a combined transport model consisting of ionized impurity scattering, phonon scattering, and grain boundary scattering in degenerate semiconductors, we were able to determine the trap density at the grain boundaries N{sub t} ? 3?×?10{sup 13} to 5?×?10{sup 13?}cm{sup ?2} and the deformation potential E{sub ac} in the range of 5?eV to 9?eV depending on the details of the transport model.

  1. Tracking Living Cells as They Differentiate in Real Time

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

    these projects will target Alzheimer's disease, macular degeneration of the retina in diabetes, and mitochondrial diseases in children. In addition, specific processes like protein...

  2. Planar and nonplanar ion acoustic shock waves in relativistic degenerate astrophysical electron-positron-ion plasmas

    SciTech Connect (OSTI)

    Ata-ur-Rahman,; Qamar, A. [Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan); National Centre for Physics, QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan); Ali, S. [National Centre for Physics, QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan); Mirza, Arshad M. [Theoretical Plasma Physics Group, Physics Department, Quaid-i-Azam University, Islamabad 45320 (Pakistan)

    2013-04-15T23:59:59.000Z

    We have studied the propagation of ion acoustic shock waves involving planar and non-planar geometries in an unmagnetized plasma, whose constituents are non-degenerate ultra-cold ions, relativistically degenerate electrons, and positrons. By using the reductive perturbation technique, Korteweg-deVries Burger and modified Korteweg-deVries Burger equations are derived. It is shown that only compressive shock waves can propagate in such a plasma system. The effects of geometry, the ion kinematic viscosity, and the positron concentration are examined on the ion acoustic shock potential and electric field profiles. It is found that the properties of ion acoustic shock waves in a non-planar geometry significantly differ from those in planar geometry. The present study has relevance to the dense plasmas, produced in laboratory (e.g., super-intense laser-dense matter experiments) and in dense astrophysical objects.

  3. Effects of trapping and finite temperature in a relativistic degenerate plasma

    SciTech Connect (OSTI)

    Shah, H. A.; Qureshi, M. N. S. [Physics Department, GC University, Lahore 54000 (Pakistan); Masood, W. [Theoretical Plasma Physics Division, PINSTECH, P.O. Nilore, Islamabad 44000 (Pakistan); Tsintsadze, N. L. [Physics Department, GC University, Lahore 54000 (Pakistan); Institute of Physics, Georgian Academy of Sciences, Tblisi 380077 (Georgia)

    2011-10-15T23:59:59.000Z

    In the present work, we have undertaken, for the first time, investigation on the effect of trapping on the formation of solitary structures in relativistic degenerate plasmas. Such plasmas have been observed in dense astrophysical objects, and in laboratory these may result due to the interaction of intense lasers with matter. We have used the relativistic Fermi-Dirac distribution to describe the dynamics of the degenerate trapped electrons by solving the kinetic equation. The Sagdeev potential approach has been employed to obtain the arbitrary amplitude solitary structures both when the plasma has been considered cold and when small temperature effects have been taken into account. The theoretical results obtained have been analyzed numerically for different parameter values, and the results have been presented graphically.

  4. Study of degenerate parabolic system modeling the hydrogen displacement in a nuclear waste repository

    E-Print Network [OSTI]

    Caro, Florian; Saad, Mazen

    2012-01-01T23:59:59.000Z

    Our goal is the mathematical analysis of a two phase (liquid and gas) two components (water and hydrogen) system modeling the hydrogen displacement in a storage site for radioactive waste. We suppose that the water is only in the liquid phase and is incompressible. The hydrogen in the gas phase is supposed compressible and could be dissolved into the water with the Henry's law. The flow is described by the conservation of the mass of each components. The model is treated without simplified assumptions on the gas density. This model is degenerated due to vanishing terms. We establish an existence result for the nonlinear degenerate parabolic system based on new energy estimate on pressures.

  5. A new type of surface waves in a fully degenerate quantum plasma

    E-Print Network [OSTI]

    Yuriy Tyshetskiy; Roman Kompaneets; Sergey V. Vladimirov

    2014-04-06T23:59:59.000Z

    We study the response of a semi-bounded one-component fully degenerate electron plasma to an initial perturbation in the electrostatic limit. We show that the part of the electric potential corresponding to surface waves in such plasma can be represented, at large times, as the sum of two terms, one term corresponding to "conventional" (Langmuir) surface waves and the other term representing a new type of surface waves resulting from specific analytic properties of degenerate plasma's dielectric response function. These two terms are characterized by different oscillation frequencies (for a given wave number), and, while the "conventional" term's amplitude decays exponentially with time, the new term is characterized by a slower, power-law decay of the oscillation amplitude and is therefore dominant at large times.

  6. Optical imaging through turbid media with a degenerate four-wave mixing correlation time gate

    DOE Patents [OSTI]

    Sappey, Andrew D. (Golden, CO)

    1998-04-14T23:59:59.000Z

    Optical imaging through turbid media is demonstrated using a degenerate four-wave mixing correlation time gate. An apparatus and method for detecting ballistic and/or snake light while rejecting unwanted diffusive light for imaging structures within highly scattering media are described. Degenerate four-wave mixing (DFWM) of a doubled YAG laser in rhodamine 590 is used to provide an ultrafast correlation time gate to discriminate against light that has undergone multiple scattering and therefore has lost memory of the structures within the scattering medium. Images have been obtained of a test cross-hair pattern through highly turbid suspensions of whole milk in water that are opaque to the naked eye, which demonstrates the utility of DFWM for imaging through turbid media. Use of DFWM as an ultrafast time gate for the detection of ballistic and/or snake light in optical mammography is discussed.

  7. From constant to non-degenerately vanishing magnetic fields in superconductivity

    E-Print Network [OSTI]

    Bernard Helffer; Ayman Kachmar

    2015-03-30T23:59:59.000Z

    We explore the relationship between two reference functions arising in the analysis of the Ginzburg-Landau functional. The first function describes the distribution of superconductivity in a type II superconductor subjected to a constant magnetic field. The second function describes the distribution of superconductivity in a type II superconductor submitted to a variable magnetic field that vanishes non-degenerately along a smooth curve.

  8. Controlled Fusion with Hot-ion Mode in a Degenerate Plasma

    SciTech Connect (OSTI)

    S. Son and N.J. Fisch

    2005-12-01T23:59:59.000Z

    n a Fermi-degenerate plasma, the rate of electron physical processes is much reduced from the classical prediction, possibly enabling new regimes for controlled nuclear fusion, including the hot-ion mode, a regime in which the ion temperature exceeds the electron temperature. Previous calculations of these processes in dense plasmas are now corrected for partial degeneracy and relativistic effects, leading to an expanded regime of self-sustained fusion.

  9. Bunching-induced asymmetry in degenerate four-wave mixing with cold atoms

    SciTech Connect (OSTI)

    Gattobigio, G. L. [Institut Non Lineaire de Nice, UMR 6618 CNRS, 1361 route des Lucioles, F-06560 Valbonne (France); Dipartimento di Fisica dell'Universita di Ferrara and INFN-Sezione di Ferrara, 44100 Ferrara (Italy); Michaud, F.; Kaiser, R. [Institut Non Lineaire de Nice, UMR 6618 CNRS, 1361 route des Lucioles, F-06560 Valbonne (France); Javaloyes, J. [Department de Fisica Interdisciplinar, IMEDEA (CSIC-UIB), C/Miquel Marques, 21, E-07190 Esporles (Spain); Tabosa, J. W. R. [Departamento de Fisica, Universidade Federal de Pernambuco, Av. Professor Luiz Freire, s/n Cidade Universitaria, 50670-901, Recife-PE, Brasil (Brazil)

    2006-10-15T23:59:59.000Z

    We have investigated degenerate four-wave mixing in a sample of cold rubidium atoms. A red-blue asymmetry is observed for high intensities of the pumping beams. This asymmetry is explained by the spatial bunching of the atoms in the nodes or antinodes of the strong standing wave of the pump beams. This explanation is confirmed by different experimental configurations and by numerical simulations.

  10. The SU(1, 1) Perelomov number coherent states and the non-degenerate parametric amplifier

    SciTech Connect (OSTI)

    Ojeda-Guillén, D., E-mail: dojedag@ipn.mx; Granados, V. D. [Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, Ed. 9, Unidad Profesional Adolfo López Mateos, C.P. 07738 México D. F. (Mexico)] [Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, Ed. 9, Unidad Profesional Adolfo López Mateos, C.P. 07738 México D. F. (Mexico); Mota, R. D. [Escuela Superior de Ingeniería Mecánica y Eléctrica, Unidad Culhuacán, Instituto Politécnico Nacional, Av. Santa Ana No. 1000, Col. San Francisco Culhuacán, Delegación Coyoacán, C.P. 04430, México D. F. (Mexico)] [Escuela Superior de Ingeniería Mecánica y Eléctrica, Unidad Culhuacán, Instituto Politécnico Nacional, Av. Santa Ana No. 1000, Col. San Francisco Culhuacán, Delegación Coyoacán, C.P. 04430, México D. F. (Mexico)

    2014-04-15T23:59:59.000Z

    We construct the Perelomov number coherent states for an arbitrary su(1, 1) group operation and study some of their properties. We introduce three operators which act on Perelomov number coherent states and close the su(1, 1) Lie algebra. By using the tilting transformation we apply our results to obtain the energy spectrum and eigenfunctions of the non-degenerate parametric amplifier. We show that these eigenfunctions are the Perelomov number coherent states of the two-dimensional harmonic oscillator.

  11. Solitons and shocks in dense astrophysical magnetoplasmas with relativistic degenerate electrons and positrons

    SciTech Connect (OSTI)

    Ali, S. [National Centre for Physics at QAU Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan)] [National Centre for Physics at QAU Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Ata-ur-Rahman [National Centre for Physics at QAU Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan) [National Centre for Physics at QAU Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan)

    2014-04-15T23:59:59.000Z

    The linear and nonlinear properties of the ion-acoustic (IA) waves are investigated in a relativistically degenerate magnetoplasma, whose constituents are the electrons, positrons, and ions. The electrons and positrons are assumed to obey the Fermi-Dirac statistics, whereas the cold ions are taken to be inertial and magnetized. In linear analysis, various limiting cases are discussed both analytically and numerically. However, for nonlinear studies, the well-known reductive perturbation technique is employed to derive the Zakharov-Kuznetsov and Zakharov-Kuznetsov Burgers equations in the presence of relativistically degenerate electrons and positrons. Furthermore, with the use of hyperbolic tangent method, the equations are simplified to admit the soliton and shock wave solutions. Numerically, it is shown that the amplitude, width, and phase speed associated with the localized IA solitons and shocks are significantly influenced by the various intrinsic plasma parameters relevant to our model. The present analysis can be useful for understanding the collective processes in dense astrophysical environments like neutron stars, where the electrons and positrons are expected to be relativistic and degenerate.

  12. Degenerate four-wave mixing spectroscopy of ultrathin Au and Pt films

    SciTech Connect (OSTI)

    Bobyrev, Yu V; Petnikova, V M; Rudenko, K V; Shuvalov, Vladimir V [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2002-09-30T23:59:59.000Z

    The results of experimental investigations of ultrathin (30 - 40 nm) metal Au and Pt films by means of picosecond degenerate four-wave mixing spectroscopy are presented. Within the model of nonlinear response formation, which takes into account the coherent superposition of contributions from many saturable interband transitions in the real spectrum of electronic states, the characteristic intraband relaxation times are determined to be 230 {+-} 30 fs and 180 {+-} 30 fs for Au and Pt films, respectively. The temperature of the electron subsystem is found to be 600 - 800 K. (nonlinear optical phenomena)

  13. Temporally stable coherent states in energy degenerate systems: The hydrogen atom

    E-Print Network [OSTI]

    Michael G. A. Crawford

    2001-01-18T23:59:59.000Z

    Klauder's recent generalization of the harmonic oscillator coherent states [J. Phys. A 29, L293 (1996)] is applicable only in non-degenerate systems, requiring some additional structure if applied to systems with degeneracies. The author suggests how this structure could be added, and applies the complete method to the hydrogen atom problem. To illustrate how a certain degree of freedom in the construction may be exercised, states are constructed which are initially localized and evolve semi-classically, and whose long time evolution exhibits "fractional revivals."

  14. Alpha-Synuclein Disrupted Dopamine Homeostasis Leads to Dopaminergic Neuron Degeneration in Caenorhabditis elegans

    E-Print Network [OSTI]

    Cao, Pengxiu; Yuan, Yiyuan; Pehek, Elizabeth A.; Moise, Alexander R.; Huang, Ying; Palczewski, Krzysztof; Feng, Zhaoyang

    2010-02-19T23:59:59.000Z

    mice [2]. Reduction of cytosolic dopamine content either genetically or pharmacologically prevents haSyn-mediated neuronal degeneration in vitro [1]. It also has been suggested that a-synuclein overexpression disrupts vesicular pH, leading... were conducted with a Leica TCS SP2 confocal microscope. The spectra used were: DsRed(lex = 543nm and lem = 580–630nm) and GFP(lex = 488nm and lem = 510– 530nm). To count fluorescent DAergic neuron numbers, living worms were immobilized with 30 m...

  15. Instanton solutions mediating tunneling between the degenerate vacua in curved space

    SciTech Connect (OSTI)

    Lee, Bum-Hoon; Lee, Wonwoo [Department of Physics and BK21 Division, and Center for Quantum Spacetime, Sogang University, Seoul 121-742 (Korea, Republic of); Lee, Chul H. [Department of Physics, Hanyang University, Seoul 133-791 (Korea, Republic of); Oh, Changheon [Department of Physics, Hanyang University, Seoul 133-791 (Korea, Republic of); Principal Researcher Center, Technovation Partners, Seoul 135-824 (Korea, Republic of)

    2010-07-15T23:59:59.000Z

    We investigate the instanton solution between the degenerate vacua in curved space. We show that there exist O(4)-symmetric solutions not only in de Sitter but also in both flat and anti-de Sitter space. The geometry of the new type of solutions is finite and preserves the Z{sub 2} symmetry. The nontrivial solution corresponding to the tunneling is possible only if gravity is taken into account. The numerical solutions as well as the analytic computations using the thin-wall approximation are presented. We expect that these solutions do not have any negative mode as in the instanton solution.

  16. Detection of OH in a flame by degenerate four-wave mixing

    SciTech Connect (OSTI)

    Ewart, P.; O'Leary, S.V.

    1986-05-01T23:59:59.000Z

    The detection of OH in a laminar premixed air-methane flame by degenerate four-wave mixing (DFWM) is reported. The four-wave mixing spectrum was recorded in the region of the R/sub 1/, R/sub 2/ band heads of the (0, 0) /sup 2/..sigma..-/sup 2/Pi transition, showing clearly resolved rotational structure. Applications of the DFWM technique to combustion diagnostics are discussed. As an example, the distribution of sodium atoms in a sodium-seeded flame has been measured using a 90/sup 0/ geometry to enhance spatial resolution.

  17. Extracellular ATP inhibits Schwann cell dedifferentiation and proliferation in an ex vivo model of Wallerian degeneration

    SciTech Connect (OSTI)

    Shin, Youn Ho; Lee, Seo Jin [Department of Anatomy, College of Medicine, Kyung Hee University, Heogi-Dong 1, Dongdaemun-Gu, Seoul 130-701 (Korea, Republic of)] [Department of Anatomy, College of Medicine, Kyung Hee University, Heogi-Dong 1, Dongdaemun-Gu, Seoul 130-701 (Korea, Republic of); Jung, Junyang, E-mail: jjung@khu.ac.kr [Department of Anatomy, College of Medicine, Kyung Hee University, Heogi-Dong 1, Dongdaemun-Gu, Seoul 130-701 (Korea, Republic of)] [Department of Anatomy, College of Medicine, Kyung Hee University, Heogi-Dong 1, Dongdaemun-Gu, Seoul 130-701 (Korea, Republic of)

    2013-01-11T23:59:59.000Z

    Highlights: Black-Right-Pointing-Pointer ATP-treated sciatic explants shows the decreased expression of p75NGFR. Black-Right-Pointing-Pointer Extracellular ATP inhibits the expression of phospho-ERK1/2. Black-Right-Pointing-Pointer Lysosomal exocytosis is involved in Schwann cell dedifferentiation. Black-Right-Pointing-Pointer Extracellular ATP blocks Schwann cell proliferation in sciatic explants. -- Abstract: After nerve injury, Schwann cells proliferate and revert to a phenotype that supports nerve regeneration. This phenotype-changing process can be viewed as Schwann cell dedifferentiation. Here, we investigated the role of extracellular ATP in Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Using several markers of Schwann cell dedifferentiation and proliferation in sciatic explants, we found that extracellular ATP inhibits Schwann cell dedifferentiation and proliferation during Wallerian degeneration. Furthermore, the blockage of lysosomal exocytosis in ATP-treated sciatic explants is sufficient to induce Schwann cell dedifferentiation. Together, these findings suggest that ATP-induced lysosomal exocytosis may be involved in Schwann cell dedifferentiation.

  18. Spectral features of the nonlinear response of high-temperature superconductor films in methods of degenerate four-photon spectroscopy

    SciTech Connect (OSTI)

    Bobyrev, Yu V; Voronov, Aleksandr V; Petnikova, V M; Rudenko, K V; Shuvalov, Vladimir V [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2005-01-31T23:59:59.000Z

    The electronic nonlinear response {chi}{sup (3)}{sub ee} of high-temperature superconductor films in methods of degenerate four-photon spectroscopy is calculated. It is shown that the model considering interband electronic transitions in a 'real' band structure with the only fitting parameter (the electron-phonon relaxation rate) well describes all the experimental spectral features of the response, and the methods of degenerate four-photon spectroscopy themselves can reveal, due to the interference character of {chi}{sup (3)}{sub ee}, the presence of the energy gap in the spectrum of states. (laser applications and other topics in quantum electronics)

  19. Low frequency electromagnetic oscillations in dense degenerate electron-positron pair plasma, with and without ions

    SciTech Connect (OSTI)

    Khan, S. A. [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan); Ayub, M. K. [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan); Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, Islamabad (Pakistan); Pohang University of Science and Technology (POSTECH), Pohang, Gyunbuk 790-784 (Korea, Republic of); Ahmad, Ali [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan); Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, Islamabad (Pakistan); Department of Physics, COMSATS Institute of Information Technology, Islamabad 44000 (Pakistan)

    2012-10-15T23:59:59.000Z

    Quantum plasma oscillations are studied in a strongly magnetized, ultra-dense plasma with degenerate electrons and positrons. The dispersive role of electron and positron quantum effects on low frequency (in comparison to electron cyclotron frequency) shear electromagnetic wave is investigated by employing hydrodynamic formulation. In the presence of ions, the density balance changes, and the electromagnetic wave (with frequency lower than the ion cyclotron frequency) is shown to couple with electrostatic ion mode under certain conditions. For such low frequency waves, it is also seen that the contribution of electron and positron degeneracy pressure is dominant as compared to their diffraction effects. The results are analyzed numerically for illustrative purpose pointing out their relevance to the dense laboratory (e.g., super-intense laser-dense matter interactions) and astrophysical plasmas.

  20. Nonlinear screening effect in an ultrarelativistic degenerate electron-positron gas

    SciTech Connect (OSTI)

    Tsintsadze, N. L. [Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan); Department of Physics, Government College University, Lahore 54000 (Pakistan); Rasheed, A.; Shah, H. A. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan)

    2009-11-15T23:59:59.000Z

    Nonlinear screening process in an ultrarelativistic degenerate electron-positron gas has been investigated by deriving a generalized nonlinear Poisson equation for the electrostatic potential. In the simple one-dimensional case, the nonlinear Poisson equation leads to Debye-like (Coulomb-like) solutions at distances larger (less) than the characteristic length. When the electrostatic energy is larger than the thermal energy, this nonlinear Poisson equation converts into the relativistic Thomas-Fermi equation whose asymptotic solution in three dimensions shows that the potential field goes to zero at infinity much more slowly than the Debye potential. The possibility of the formation of a bound state in electron-positron plasma is also indicated. Further, it is investigated that the strong spatial fluctuations of the potential field may reduce the screening length and that the root mean square of this spatial fluctuating potential goes to zero for large r rather slowly as compared to the case of the Debye potential.

  1. On the ordinary mode and whistler mode instabilities in the degenerate anisotropic plasmas

    SciTech Connect (OSTI)

    Iqbal, Z.; Hussain, A. [Department of Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan)] [Department of Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan); Murtaza, G. [Department of Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan) [Department of Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan); Salam Chair in Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan); Tsintsadze, N. L., E-mail: abbasiravian@yahoo.com [Department of Plasma Physics, E. Andronikashvili Institute of Physics, Tbilisi, Georgia (United States); Department of Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan)

    2014-03-15T23:59:59.000Z

    Employing Vlasov-Maxwell set of equations, we have investigated the O-mode and whistler mode instability in a degenerate anisotropic magnetoplasma environment and compared the results to those reported for classical plasmas. We propose the excitation of a new banded type of instability for the O-mode case, which grows at some particular values of temperature anisotropy and external magnetic field. For the case of whistler wave, we observe instability saturation mechanism similar to the case of classical plasmas. The existence of both O-mode and whistler mode instability has been observed only for some specific range of unstable wavenumbers. The possible excitation of such instabilities in solid state plasma has been discussed, particularly for semiconductor and semimetal plasmas.

  2. Ion-acoustic solitary waves in ultra-relativistic degenerate pair-ion plasmas

    SciTech Connect (OSTI)

    Rasheed, A.; Tsintsadze, N. L. [Department of Physics, G.C. University, Lahore 54000 (Pakistan); Salam Chair in Physics, G.C. University, Lahore 54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, G.C. University, Lahore 54000 (Pakistan)

    2011-11-15T23:59:59.000Z

    The arbitrary and the small amplitude ion-acoustic solitary waves (IASWs) have been studied. The former is studied by using the Sagdeev pseudo-potential approach in a plasma consisting of the degenerate ultrarelativistic electrons, positrons, and the non-relativistic classical ions. It is seen that only compressive solitary waves can propagate through such plasmas. The numerical calculations show that the region of existence of the ion-acoustic solitary waves depends upon the positron (ion) number density and the plasma thermal temperature. This study is appropriate for applications in inertial confinement fusion laboratory research as well as the study of astrophysical dense objects such as white dwarf and dense neutron stars.

  3. The Modelling of Degenerate Neck Pinch Singularities in Ricci Flow by Bryant Solitons

    E-Print Network [OSTI]

    David Garfinkle; James Isenberg

    2007-09-04T23:59:59.000Z

    In earlier work, carrying out numerical simulations of the Ricci flow of families of rotationally symmetric geometries on $S3$, we have found strong support for the contention that (at least in the rotationally symmetric case) the Ricci flow for a ``critical'' initial geometry - one which is at the transition point between initial geometries (on $S^3$) whose volume-normalized Ricci flows develop a singular neck pinch, and other initial geometries whose volume normalized Ricci flows converge to a round sphere - evolves into a ``degenerate neck pinch.'' That is, we have seen in this earlier work that the Ricci flows for the critical geometries become locally cylindrical in a neighborhood of the initial pinching, and have the maximum amount of curvature at one or both of the poles. Here, we explore the behavior of these flows at the poles, and find strong support for the conjecture that the Bryant steady solitons accurately model this polar flow.

  4. Nonlinear response of ultrathin Ni films in degenerate four-photon spectroscopy

    SciTech Connect (OSTI)

    Kuznetsova, L P [M.V. Lomonosov Moscow State University, Moscow (Russian Federation); Petnikova, V M; Rudenko, K V; Shuvalov, Vladimir V [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2000-02-28T23:59:59.000Z

    The ultrathin (17 - 25 nm thick) continuous Ni films deposited on K8 glass and ZrO{sub 2} substrates are experimentally studied. The degenerate four-photon spectroscopy showed typical resonances in the dependence of the self-diffraction efficiency on the wavelength of pump components. It is shown within the framework of the model of electronic cubic nonlinear susceptibility - taking into account the real structure of the spectrum of electronic states of Ni, its quantum-size renormalisation and spin splitting, the inter- and intraband relaxation, saturation, and the selection rules for the electronic transitions - that the electronic subsystem makes the dominant contribution to the nonlinear response of Ni films to picosecond laser pulses (20 ps long) in the 620 - 634 nm spectral range. The interband-polarisation relaxation time T{sub 2} was found to be {approx}200 fs. (laser applications and other topics in quantum electronics)

  5. Quantitative degenerate four-wave mixing spectroscopy: Probes for molecular species

    SciTech Connect (OSTI)

    Farrow, R.; Rakestraw, D.; Paul, P.; Lucht, R.; Danehy, P.; Friedman-Hill, E.; Germann, G. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01T23:59:59.000Z

    Resonant degenerate four-wave mixing (DFWM) is currently the subject of intensive investigation as a sensitive diagnostic tool for molecular species. DFWM has the advantage of generating a coherent (beam-like) signal which results in null-background detection and provides excellent immunity to background-light interference. Since multiple one-photon resonances are involved in the signal generation process, the DFWM technique can allow sensitive detection of molecules via electronic, vibrational or rotational transitions. These properties combine to make DFWM a widely applicable diagnostic technique for the probing of molecular species. The authors are conducting fundamental and applied investigations of DFWM for quantitative measurements of trace species in reacting gases. During the past year, efforts have been focussed in two areas: (1) understanding the effects of collisional processes on the DFWM signal generation process, and (2) exploring the applicability of infrared DFWM to detect polyatomic molecules via rovibrational transitions.

  6. Bethe Ansatz and Ordinary Differential Equation Correspondence for Degenerate Gaudin Models

    E-Print Network [OSTI]

    Omar El Araby; Vladimir Gritsev; Alexandre Faribault

    2012-04-25T23:59:59.000Z

    In this work, we generalize the numerical approach to Gaudin models developed earlier by us to degenerate systems showing that their treatment is surprisingly convenient from a numerical point of view. In fact, high degeneracies not only reduce the number of relevant states in the Hilbert space by a non negligible fraction, they also allow to write the relevant equations in the form of sparse matrix equations. Moreover, we introduce a new inversion method based on a basis of barycentric polynomials which leads to a more stable and efficient root extraction which most importantly avoids the necessity of working with arbitrary precision. As an example we show the results of our procedure applied to the Richardson model on a square lattice.

  7. Degenerate three-level laser with parametric amplifier and squeezed vacuum

    E-Print Network [OSTI]

    Eyob Alebachew; K. Fesseha

    2007-01-31T23:59:59.000Z

    Applying stochastic differential equations, we study the squeezing and statistical properties of the cavity and output modes of a degenerate three-level laser whose cavity contains a parametric amplifier and coupled to a squeezed vacuum reservoir. We consider the case in which the top and bottom levels of the three-level cascade atoms injected into the cavity are coupled by the pump mode emerging from the parametric amplifier. It turns out that the presence of the squeezed vacuum reservoir and the parametric amplifier contribute considerably to the mean photon number and the degree of squeezing of the cavity and output modes. It appears that almost perfect squeezing can be achieved at steady state and at threshold for a suitable choice of parameters.

  8. The Construction of Spinor Fields on Manifolds with Smooth Degenerate Metrics

    E-Print Network [OSTI]

    J Schray; T Dray; C A Manogue; R W Tucker; C Wang

    1996-05-17T23:59:59.000Z

    We examine some of the subtleties inherent in formulating a theory of spinors on a manifold with a smooth degenerate metric. We concentrate on the case where the metric is singular on a hypersurface that partitions the manifold into Lorentzian and Euclidean domains. We introduce the notion of a complex spinor fibration to make precise the meaning of continuity of a spinor field and give an expression for the components of a local spinor connection that is valid in the absence of a frame of local orthonormal vectors. These considerations enable one to construct a Dirac equation for the discussion of the behavior of spinors in the vicinity of the metric degeneracy. We conclude that the theory contains more freedom than the spacetime Dirac theory and we discuss some of the implications of this for the continuity of conserved currents.

  9. Production of bosonic molecules in the nonequilibrium dynamics of a degenerate Fermi gas across a Feshbach resonance

    E-Print Network [OSTI]

    Dobrescu, Bogdan E.

    2009-06-02T23:59:59.000Z

    , 73], spin transitions, relaxation and hysteresis in nanomagnets [74, 75, 76, 77, 78], Bose-Einstein condensates [79, 80, 81, 82, 83, 84], production of Feshbach molecules from quantum degenerate Fermi gases [16, 17, 18, 19, 21, 20, 22, 23, 24...

  10. Non-degenerate shell-model effective interactions from the Okamoto-Suzuki and Krenciglowa-Kuo iteration methods

    E-Print Network [OSTI]

    Huan Dong; T. T. S. Kuo; J. W. Holt

    2011-05-23T23:59:59.000Z

    We present calculations of shell-model effective interactions for both degenerate and non-degenerate model spaces using the Krenciglowa-Kuo (KK) and the extended Krenciglowa-Kuo iteration method recently developed by Okamoto, Suzuki {\\it et al.} (EKKO). The starting point is the low-momentum nucleon-nucleon interaction $V_{low-k}$ obtained from the N$^3$LO chiral two-nucleon interaction. The model spaces spanned by the $sd$ and $sdpf$ shells are both considered. With a solvable model, we show that both the KK and EKKO methods are convenient for deriving the effective interactions for non-degenerate model spaces. The EKKO method is especially desirable in this situation since the vertex function $\\hat Z$-box employed therein is well behaved while the corresponding vertex function $\\hat Q$-box employed in the Lee-Suzuki (LS) and KK methods may have singularities. The converged shell-model effective interactions given by the EKKO and KK methods are equivalent, although the former method is considerably more efficient. The degenerate $sd$-shell effective interactions given by the LS method are practically identical to those from the EKKO and KK methods. Results of the $sd$ one-shell and $sdpf$ two-shell calculations for $^{18}$O, $^{18}$F, $^{19}$O and $^{19}$F using the EKKO effective interactions are compared, and the importance of the shell-model three-nucleon forces is discussed.

  11. Age-Related Changes in Task Related Functional Network Connectivity

    E-Print Network [OSTI]

    the information load [2,3,4], retention interval [5,6] and response time duration [7,8]. Results from fMRI studies-serving these processes have been elucidated with experimental manipulations that vary task demands by altering with these alterations in task demands [9]. Advancing age is associated with decreased performance on verbal working

  12. Age Related Changes in Motion Perception and Perceptual Learning

    E-Print Network [OSTI]

    Bower, Jeffrey Dennis

    2010-01-01T23:59:59.000Z

    simple stimuli after training. This type of learning differsfrom other types of learning in that it is hypothesized toin the other type of stimuli, transfer of learning between

  13. age related variations: Topics by E-print Network

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

    unclear. Antonio Marin-Franch; Antonio Aparicio; Giampaolo Piotto; Alfred Rosenberg; Brian Chaboyer; Ata Sarajedini; Michael Siegel; Jay Anderson; Luigi R. Bedin; Aaron...

  14. Reaction-in-Flight Neutrons as a Test of Stopping Power in Degenerate Plasmas

    E-Print Network [OSTI]

    A. C. Hayes; Gerard Jungman; A. E. Schulz; M. Boswell; M. M. Fowler; G. Grim; A. Klein; R. S. Rundberg; J. B. Wilhelmy; D. Wilson

    2014-11-25T23:59:59.000Z

    We present the first measurements of reaction-in-flight (RIF) neutrons in an inertial confinement fusion system. The experiments were carried out at the National Ignition Facility, using both Low Foot and High Foot drives and cryogenic plastic capsules. In both cases, the high-energy RIF ($E_n>$ 15 MeV) component of the neutron spectrum was found to be about $10^{-4}$ of the total. The majority of the RIF neutrons were produced in the dense cold fuel surrounding the burning hotspot of the capsule and the data are consistent with a compressed cold fuel that is moderately to strongly coupled $(\\Gamma\\sim$0.6) and electron degenerate $(\\theta_\\mathrm{Fermi}/\\theta_e\\sim$4). The production of RIF neutrons is controlled by the stopping power in the plasma. Thus, the current RIF measurements provide a unique test of stopping power models in an experimentally unexplored plasma regime. We find that the measured RIF data strongly constrain stopping models in warm dense plasma conditions and some models are ruled out by our analysis of these experiments.

  15. Electrostatic soliton and double layer structures in unmagnetized degenerate pair plasmas

    SciTech Connect (OSTI)

    Mahmood, S. [Theoretical Plasma Physics Division (TPPD), PINSTECH, P.O. Nilore, Islamabad 44000 (Pakistan); National Centre for Physics, Quaid-i-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Department of Physics and Applied Mathematics (DPAM), PIEAS, P.O. Nilore, Islamabad 44000 (Pakistan); Khan, S. A. [National Centre for Physics, Quaid-i-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan); Department of Physics, COMSATS Institute of Information Technology (CIIT), Islamabad 44000 (Pakistan); Ur-Rehman, H. [Theoretical Plasma Physics Division (TPPD), PINSTECH, P.O. Nilore, Islamabad 44000 (Pakistan); Department of Physics and Applied Mathematics (DPAM), PIEAS, P.O. Nilore, Islamabad 44000 (Pakistan)

    2010-11-15T23:59:59.000Z

    The acoustic solitons and double layers are studied in unmagnetized quantum electron-positron plasmas in the presence of stationary ions. The quantum hydrodynamic model is employed and reductive perturbation method is used to derive the Korteweg-de Vries (KdV) and extended KdV equations for solitons and double layers, respectively. It is found that in the linear limit both slow acoustic and fast Langmuir waves can propagate in such type of quantum plasmas like in classical pair-ion or pair plasmas. The amplitude and width of the electrostatic solitons are found to be decreasing with the increase in concentration of positrons (or decrease in the concentration of ions) in degenerate electron-positron-ion plasmas. It is found that only rarefactive double layer can exist in such plasmas which depend on various parameters. The dependence of double layer structure on ion concentration and quantum diffraction effects of electrons and positrons are also discussed. The results are also elaborated graphically by considering dense plasma parameters in the outer layers of astrophysical objects such as white dwarfs and neutron stars.

  16. Acceleration and dynamics of an electron in the degenerate and magnetized plasma elliptical waveguide

    SciTech Connect (OSTI)

    Abdoli-Arani, A.; Jazi, B. [Department of Photonics, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Shokri, B. [Physics Department and Laser-Plasma Research Institute, G. C. Shahid Beheshti University, Tehran (Iran, Islamic Republic of)

    2013-02-15T23:59:59.000Z

    The dynamics and energy gain of an electron in the field of a transverse magnetic wave propagating inside an elliptical degenerate plasma waveguide is analytically investigated by finding the field components of the TM{sub mr} mode in this waveguide. Besides, by solving the relativistic momentum and energy equations the deflection angle and the acceleration gradient of the electron in the waveguide are obtained. Furthermore, the field components of the hybrid mode and the transferred power in the presence of the magnetic field in this waveguide are found. Also by applying the boundary conditions at the plasma-conductor interface, we calculate the dispersion relation. It is shown that the cutoff frequency of this mode is dependent on the plasma density but independent of the magnetic field. Then, a single-electron model for numerical calculations of the electron deflection angle and acceleration gradient inside the magnetized plasma-filled elliptical waveguide is generally presented to be used as a cascading process for the acceleration purposes.

  17. Electromagnetically induced absorption due to transfer of population in degenerate two-level systems

    SciTech Connect (OSTI)

    Goren, C.; Rosenbluh, M. [Department of Physics, Bar-Ilan University, Ramat Gan 52900 (Israel); Wilson-Gordon, A.D.; Friedmann, H. [Department of Chemistry, Bar-Ilan University, Ramat Gan 52900 (Israel)

    2004-10-01T23:59:59.000Z

    We predict the occurrence of electromagnetically induced absorption (EIA) in cycling degenerate two-level transitions where F{sub e}=F{sub g}+1 and F{sub g}>0, interacting with pump and probe lasers with the same polarization. The EIA is due to transfer of population (TOP) between the Zeeman levels of the ground hyperfine state, rather than transfer of coherence (TOC) which occurs for perpendicularly polarized lasers. We model EIA-TOP using a double two-level system (TLS) which we compare with the four-level N system, which models EIA-TOC. When the pump intensity is low, both models give an EIA peak at line center. The effect of introducing phase-changing collisions is studied, in the presence and absence of Doppler broadening, for both the double TLS and N systems. In the presence of phase-changing collisions, the central EIA peaks are narrowed in both models and persist to higher pump Rabi frequencies than in the absence of collisions. In the double TLS, in the presence of Doppler broadening, the central EIA-TOP peak becomes narrower and does not develop a dip in its center, in contrast to the N system. The central dip that appears in the Doppler-broadened EIA-TOC spectrum can be wiped out by adding phase-changing collisions. We demonstrate that EIA-TOP can be obtained for realistic atomic transitions interacting with lasers that have the same polarization.

  18. Smoothed Particle Hydrodynamics simulations of the core-degenerate scenario for Type Ia supernovae

    E-Print Network [OSTI]

    Aznar-Siguán, G; Lorén-Aguilar, P; Soker, N; Kashi, A

    2015-01-01T23:59:59.000Z

    The core-degenerate (CD) scenario for type Ia supernovae (SN Ia) involves the merger of the hot core of an asymptotic giant branch (AGB) star and a white dwarf, and might contribute a non-negligible fraction of all thermonuclear supernovae. Despite its potential interest, very few studies, and based on only crude simplifications, have been devoted to investigate this possible scenario, compared with the large efforts invested to study some other scenarios. Here we perform the first three-dimensional simulations of the merger phase, and find that this process can lead to the formation of a massive white dwarf, as required by this scenario. We consider two situations, according to the mass of the circumbinary disk formed around the system during the final stages of the common envelope phase. If the disk is massive enough, the stars merge on a highly eccentric orbit. Otherwise, the merger occurs after the circumbinary disk has been ejected and gravitational wave radiation has brought the stars close to the Roche...

  19. Exact solution for the degenerate ground-state manifold of a strongly interacting one-dimensional Bose-Fermi mixture

    SciTech Connect (OSTI)

    Fang, Bess [Department of Physics, Block S12, Faculty of Science, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore); Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543 (Singapore); Vignolo, Patrizia; Gattobigio, Mario [Universite de Nice-Sophia Antipolis, Institut Non Lineaire de Nice, CNRS, 1361 route des Lucioles, F-06560 Valbonne (France); Miniatura, Christian [Department of Physics, Block S12, Faculty of Science, National University of Singapore, 2 Science Drive 3, Singapore 117542 (Singapore); Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543 (Singapore); Universite de Nice-Sophia Antipolis, Institut Non Lineaire de Nice, CNRS, 1361 route des Lucioles, F-06560 Valbonne (France); Minguzzi, Anna [Universite Grenoble 1, CNRS, LPMMC, UMR5493, Maison des Magisteres, F-38042 Grenoble (France)

    2011-08-15T23:59:59.000Z

    We present the exact solution for the many-body wavefunction of a one-dimensional mixture of bosons and spin-polarized fermions with equal masses and infinitely strong repulsive interactions under external confinement. Such a model displays a large degeneracy of the ground state. Using a generalized Bose-Fermi mapping, we find the solution for the whole set of ground-state wave functions of the degenerate manifold and we characterize them according to group-symmetry considerations. We find that the density profile and the momentum distribution depends on the symmetry of the solution. By combining the wave functions of the degenerate manifold with suitable symmetry and guided by the strong-coupling form of the Bethe-Ansatz solution for the homogeneous system, we propose an analytic expression for the many-body wave function of the inhomogeneous system which well describes the ground state at finite, large, and equal interaction strengths, as validated by numerical simulations.

  20. Ultra-low power, Zeno effect based optical modulation in a degenerate V-system with a

    E-Print Network [OSTI]

    Shahriar, Selim

    Ultra-low power, Zeno effect based optical modulation in a degenerate V-system with a tapered nano@northwestern.edu Abstract: We demonstrate an ultra-low light level optical modulator using a tapered nano fiber embedded. For a control power of 40 nW and a signal power of 100 pW, we observe near 100% modulation. The ultra-low power

  1. Common Variants at 9p21 and 8q22 Are Associated with Increased Susceptibility to Optic Nerve Degeneration in Glaucoma

    E-Print Network [OSTI]

    Ernst, Jason M.

    Optic nerve degeneration caused by glaucoma is a leading cause of blindness worldwide. Patients affected by the normal-pressure form of glaucoma are more likely to harbor risk alleles for glaucoma-related optic nerve ...

  2. Biocompatibility of an implantable ophthalmic drug delivery device

    E-Print Network [OSTI]

    Cohen, Sarah J. (Sarah Jennifer)

    2007-01-01T23:59:59.000Z

    Diseases of the posterior eye present clinicians with a treatment challenge mainly due to the region's inaccessible location. Several drugs, including those available for the treatment of exudative age-related macular ...

  3. EVOLUTION OF POST-IMPACT REMNANT HELIUM STARS IN TYPE Ia SUPERNOVA REMNANTS WITHIN THE SINGLE-DEGENERATE SCENARIO

    SciTech Connect (OSTI)

    Pan, Kuo-Chuan; Ricker, Paul M. [Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801 (United States); Taam, Ronald E., E-mail: kpan2@illinois.edu, E-mail: pmricker@illinois.edu, E-mail: r-taam@northwestern.edu [Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States)

    2013-08-10T23:59:59.000Z

    The progenitor systems of Type Ia supernovae (SNe Ia) are still under debate. Based on recent hydrodynamics simulations, non-degenerate companions in the single-degenerate scenario (SDS) should survive the supernova (SN) impact. One way to distinguish between the SDS and the double-degenerate scenario is to search for the post-impact remnant stars (PIRSs) in SN Ia remnants. Using a technique that combines multi-dimensional hydrodynamics simulations with one-dimensional stellar evolution simulations, we have examined the post-impact evolution of helium-rich binary companions in the SDS. It is found that these helium-rich PIRSs (He PIRSs) dramatically expand and evolve to a luminous phase (L {approx} 10{sup 4} L{sub Sun }) about 10 yr after an SN explosion. Subsequently, they contract and evolve to become hot blue-subdwarf-like (sdO-like) stars by releasing gravitational energy, persisting as sdO-like stars for several million years before evolving to the helium red-giant phase. We therefore predict that a luminous OB-like star should be detectable within {approx}30 yr after the SN explosion. Thereafter, it will shrink and become an sdO-like star in the central regions of SN Ia remnants within star-forming regions for SN Ia progenitors evolved via the helium-star channel in the SDS. These He PIRSs are predicted to be rapidly rotating (v{sub rot} {approx}> 50 km s{sup -1}) and to have high spatial velocities (v{sub linear} {approx}> 500 km s{sup -1}). Furthermore, if SN remnants have diffused away and are not recognizable at a later stage, He PIRSs could be an additional source of single sdO stars and/or hypervelocity stars.

  4. Generating highly squeezed Hybrid Laguerre-Gauss modes in large-Fresnel-number Degenerate Optical Parametric Oscillators

    E-Print Network [OSTI]

    Carlos Navarrete-Benlloch; Germán J. de Valcárcel; Eugenio Roldán

    2009-10-13T23:59:59.000Z

    We theoretically describe the quantum properties of a large Fresnel number degenerate optical parametric oscillator with spherical mirrors that is pumped by a Gaussian beam. The resonator is tuned so that the resonance frequency of a given transverse mode family coincides with the down-converted frequency. After demonstrating that only the lower orbital angular momentum (OAM) Laguerre-Gauss modes are amplified above threshold, we focus on the quantum properties of the rest of (classically empty) modes. We find that combinations of opposite OAM (Hybrid Laguerre-Gauss modes) can exhibit arbitrary large quadrature squeezing for the lower OAM non amplified modes.

  5. Right-handed Majorana Neutrino Mass Matrices for Generating Bimaximal Mixings in Degenerate and Inverted Models of Neutrinos

    E-Print Network [OSTI]

    Mahadev Patgiri; N. Nimai Singh

    2003-01-29T23:59:59.000Z

    An attempt is made to generate the bimaximal mixings of the three species of neutrinos from the textures of the right-handed Majorana neutrino mass matrices. We extend our earlier work in this paper for the generation of the nearly degenerate as well as the inverted hierarchical models of the left-handed Majorana neutrino mass matrices using the non-diagonal textures of the right-handed Majorana neutrino mass matrices and the diagonal form of the Dirac neutrino mass matrices, within the frame work of the seesaw mechanism in a model independent way. Such Majorana neutrino mass models are important to explain the recently reported result on the neutrinoless double beat decay (0/nu/beta/beta) experiment,together with the earlier established data on LMA MSW solar and atmospheric neutrino oscillations.

  6. Elastic properties of the degenerate f.c.c. crystal of polydisperse soft dimers at zero temperature

    E-Print Network [OSTI]

    J. W. Narojczyk; K. W. Wojciechowski

    2015-04-12T23:59:59.000Z

    Elastic properties of soft, three-dimensional dimers, interacting through site-site n-inverse-power potential, are determined by computer simulations at zero temperature. The degenerate crystal of dimers exhibiting (Gaussian) size distribution of atomic diameters - i.e. size polydispersity - is studied at the molecular number density $1/\\sqrt{2}$; the distance between centers of atoms forming dimers is considered as a length unit. It is shown that, at the fixed number density of the dimers, increasing polydispersity causes, typically, an increase of pressure, elastic constants and Poisson's ratio; the latter is positive in most direction. A direction is found, however, in which the size polydispersity causes substantial decrease of Poisson's ratio, down to negative values for large $n$. Thus, the system is partially auxetic for large polydispersity and large n.

  7. Elastic properties of the degenerate f.c.c. crystal of polydisperse soft dimers at zero temperature

    E-Print Network [OSTI]

    Narojczyk, J W

    2015-01-01T23:59:59.000Z

    Elastic properties of soft, three-dimensional dimers, interacting through site-site n-inverse-power potential, are determined by computer simulations at zero temperature. The degenerate crystal of dimers exhibiting (Gaussian) size distribution of atomic diameters - i.e. size polydispersity - is studied at the molecular number density $1/\\sqrt{2}$; the distance between centers of atoms forming dimers is considered as a length unit. It is shown that, at the fixed number density of the dimers, increasing polydispersity causes, typically, an increase of pressure, elastic constants and Poisson's ratio; the latter is positive in most direction. A direction is found, however, in which the size polydispersity causes substantial decrease of Poisson's ratio, down to negative values for large $n$. Thus, the system is partially auxetic for large polydispersity and large n.

  8. Quasiparticle spectrum and dynamical stability of an atomic Bose-Einstein condensate coupled to a degenerate Fermi gas

    E-Print Network [OSTI]

    C. P. Search; H. Pu; W. Zhang; P. Meystre

    2001-12-20T23:59:59.000Z

    The quasiparticle excitations and dynamical stability of an atomic Bose-Einstein condensate coupled to a quantum degenerate Fermi gas of atoms at zero temperature is studied. The Fermi gas is assumed to be either in the normal state or to have undergone a phase transition to a superfluid state by forming Cooper pairs. The quasiparticle excitations of the Bose-Einstein condensate exhibit a dynamical instability due to a resonant exchange of energy and momentum with quasiparticle excitations of the Fermi gas. The stability regime for the bosons depends on whether the Fermi gas is in the normal state or in the superfluid state. We show that the energy gap in the quasiparticle spectrum for the superfluid state stabilizes the low energy energy excitations of the condensate. In the stable regime, we calculate the boson quasiparticle spectrum, which is modified by the fluctuations in the density of the Fermi gas.

  9. Microwave degenerate parametric down-conversion with a single cyclic three-level system in circuit QED

    E-Print Network [OSTI]

    Z. H. Wang; C. P. Sun; Yong Li

    2014-09-09T23:59:59.000Z

    With the assistance of a single cyclic three-level system, which can be realized by a superconducting flux qubit, we study theoretically the degenerate microwave parametric down-conversion (PDC) in a superconducting transmission line resonator with the fundamental and second harmonic modes involved. By adiabatically eliminating the excited states of the three-level system, we obtain an effective microwave PDC Hamiltonian for the two resonator modes in such a circuit QED system. The corresponding PDC efficiency in our model can be much larger than that in the similar circuit QED system based on a single two-level superconducting qubit [K. Moon and S. M. Girvin, Phys. Rev. Lett. {\\bf 95}, 140504 (2005)]. Furthermore, we consider the squeezing and bunching behavior of the fundamental mode resulting from the coherent drive to the second harmonic one.

  10. Spectroscopic Analysis of the DAB White Dwarf PG 1115+166: An Unresolved DA + DB Degenerate Binary

    E-Print Network [OSTI]

    P. Bergeron; James Liebert

    2001-10-25T23:59:59.000Z

    A spectroscopic analysis of the DAB white dwarf PG 1115+166 is presented. The observed hydrogen and helium line profiles are shown to be incompatible with model spectra calculated under the assumption of homogeneous or stratified chemical compositions. In contrast, an excellent fit to the optical spectrum of PG 1115+166 can be achieved if the object is interpreted as an unresolved double degenerate composed of a hydrogen-line DA star and a helium-line DB star. The atmospheric parameters obtained from the best fit are Teff=22,090 K and log g=8.12 for the DA star, Teff=16,210 K and log g=8.19 for the DB star. This binary interpretation is consistent with the results recently reported by Burleigh et al. that PG 1115+166 also exhibits radial velocity variations. The implications of this discovery with respect to the DAB spectral class are discussed.

  11. A R T I C L E Induction of tumor angiogenesis by Slit-Robo signaling and

    E-Print Network [OSTI]

    Tian, Weidong

    in axon guidance (Wang et al., 1999; macular degeneration, neovascular glaucoma, psoriasis, rheu- Brose et; Brose and Jain, 2000). The obligatory requirement of angiogenesis for et al., 1999; Li et al., 1999

  12. arXiv:1105.4207v1[math.RT]21May2011 Affine and degenerate affine BMW algebras: The center

    E-Print Network [OSTI]

    Ram, Arun

    arXiv:1105.4207v1[math.RT]21May2011 Affine and degenerate affine BMW algebras: The center Zajj and affine BMW algebras arise naturally in the context of Schur- Weyl duality for orthogonal and symplectic Lie algebras and quantum groups, respectively. Cyclotomic BMW algebras, affine Hecke algebras

  13. Nonlinear theory of ionic sound waves in a hot quantum-degenerate electron-positron-ion plasma

    SciTech Connect (OSTI)

    Dubinov, A. E., E-mail: dubinov-ae@yandex.ru; Sazonkin, M. A., E-mail: figma@mail.r [Sarov State Physicotechnical Institute (Russian Federation)

    2010-11-15T23:59:59.000Z

    A collisionless nonmagnetized e-p-i plasma consisting of quantum-degenerate gases of ions, electrons, and positrons at nonzero temperatures is considered. The dispersion equation for isothermal ionic sound waves is derived and analyzed, and an exact expression is obtained for the linear velocity of ionic sound. Analysis of the dispersion equation has made it possible to determine the ranges of parameters in which nonlinear solutions in the form of solitons should be sought. A nonlinear theory of isothermal ionic sound waves is developed and used for obtaining and analyzing the exact solution to the system of initial equations. Analysis has been carried out by the method of the Bernoulli pseudopotential. The ranges of phase velocities of periodic ionic sound waves and soliton velocities are determined. It is shown that in the plasma under investigation, these ranges do not overlap and that the soliton velocity cannot be lower than the linear velocity of ionic sound. The profiles of physical quantities in a periodic wave and in a soliton are constructed, as well as the dependences of the velocity of sound and the critical velocity on the ionic concentration in the plasma. It is shown that these velocities increase with the ion concentration.

  14. Separated spin-up and spin-down quantum hydrodynamics of degenerated electrons: spin-electron acoustic wave appearance

    E-Print Network [OSTI]

    Pavel A. Andreev

    2014-05-04T23:59:59.000Z

    Quantum hydrodynamic (QHD) model of charged spin-1/2 particles contains physical quantities defined for all particles of a species including particles with spin-up and with spin-down. Different population of states with different spin direction is included in the spin density (magnetization). In this paper we derive a QHD model, which separately describes spin-up electrons and spin-down electrons. Hence we consider electrons with different projection of spin on the preferable direction as two different species of particles. We show that numbers of particles with different spin direction do not conserve. Hence the continuity equations contain sources of particles. These sources are caused by the interactions of spins with magnetic field. Terms of similar nature arise in the Euler equation. We have that z-projection of the spin density is no longer an independent variable. It is proportional to difference between concentrations of electrons with spin-up and electrons with spin-down. In terms of new model we consider propagation of waves in magnetized plasmas of degenerate electrons and motionless ions. We show that new form of QHD equations gives all solutions obtained from traditional form of QHD equations with no distinguish of spin-up and spin-down states. But it also reveals a sound-like solution we call the spin-electron acoustic wave. Coincidence of most solutions is expected since we started derivation with the same basic equation.

  15. Monte Carlo Study of Strongly-Interacting Degenerate Fermions: a Model for Voltage-Biased Bilayer Graphene

    E-Print Network [OSTI]

    Wes Armour; Simon Hands; Costas Strouthos

    2013-02-07T23:59:59.000Z

    We formulate a model of N_f=4 flavors of relativistic fermion in 2+1d in the presence of a chemical potential mu coupled to two flavor doublets with opposite sign, akin to isopsin chemical potential in QCD. This is argued to be an effective theory for low energy electronic excitations in bilayer graphene, in which an applied voltage between the layers ensures equal populations of particles on one layer and holes on the other. The model is then reformulated on a spacetime lattice using staggered fermions, and in the absence of a sign problem, simulated using an orthodox hybrid Monte Carlo algorithm. With the coupling strength chosen to be close to a quantum critical point believed to exist for N_fdegenerate fermion system, with a remnant Fermi surface distorted by a superfluid excitonic condensate. The model thus shows qualitatively different behaviour to any model with mu=/=0 previously studied by lattice simulation.

  16. RXJ0806.3+1527: a double degenerate binary with the shortest known orbital period (321s)

    E-Print Network [OSTI]

    G. L. Israel; W. Hummel; S. Covino; S. Campana; I. Appenzeller; W. Gassler; K. -H. Mantel; G. Marconi; C. W. Mauche; U. Munari; I. Negueruela; H. Nicklas; G. Rupprecht; R. L. Smart; O. Stahl; L. Stella

    2002-03-04T23:59:59.000Z

    We carried out optical observations of the field of the X-ray pulsator RXJ0806.3+1527. A blue V=21.1 star was found to be the only object consistent with the X-ray position. VLT FORS spectra revealed a blue continuum with no intrinsic absorption lines. Broad (v~1500 km/s), low equivalent width (about -1/-6A) emission lines from the HeII Pickering series were clearly detected. B, V and R time-resolved photometry revealed the presence of about 15% pulsations at the 321s X-ray period, confirming the identification. These findings, together with the period stability and absence of any additional modulation in the 1min-5hr period range, argue in favour of the orbital interpretation of the 321s pulsations. The most likely scenario is thus that RXJ0806.3+1527 is a double degenerate system of the AM CVn class. This would make RXJ0806.3+1527 the shortest orbital period binary currently known and one of the best candidates for gravitational wave detection.

  17. Summary of current research interests Much of our work includes the morphological characterisation of human

    E-Print Network [OSTI]

    Saunders, Mark

    , Bailey T, Zhang J, Knupp C, Cheetham ME, Greenwood J, Luthert PJ. Modulation of Sub-RPE deposits in vitro-related macular degeneration. Prog Ret Eye Res (2001) 20: 705-732. Chong NHV, Alexander RA, Waters L, Barnett KC in hereditary retinal degeneration. IOVS (1999) 40: 1298-1305 Bailey A, Luthert P, Dean A, Harding B, Janota I

  18. Is Lutein a Physiologically Important Ligand for Transthyretin in Humans?

    SciTech Connect (OSTI)

    Liwei Chen

    2003-05-31T23:59:59.000Z

    Lutein and zeaxanthin are the only carotenoids accumulated in the macula of the human retina and are known as the macular pigments (MP). These pigments account for the yellow color of the macula and appear to play an important role in protecting against age-related macular degeneration (AMD). The uptake of lutein and zeaxanthin in human eyes is remarkably specific. It is likely that specific transport or binding proteins are involved. The objective is to determine whether transthyretin (TTR) is a transport protein in human plasma and could thus deliver lutein from the blood to the retina. In this study, they used a biosynthetic {sup 13}C-lutein tracer and gas chromatography-combustion interfaced-isotope ratio mass spectrometry (GCC-IRMS) to gain the requisite sensitivity to detect the minute amounts of lutein expected as a physiological ligand for human transthyretin. The biosynthetic {sup 13}C-labeled lutein tracer was purified from algae. Healthy women (n = 4) each ingested 1 mg of {sup 13}C-labeled lutein daily for 3 days and a blood sample was collected 24 hours after the final dose. Plasma TTR was isolated by retinol-binding protein (RBP)-sepharose affinity chromatography and extracted with chloroform. The {sup 13}C/{sup 12}C ratio in the TTR extract was measured by GCC-IRMS. There was no {sup 13}C-lutein enrichment in the pure TTR extract. This result indicated that lutein is not associated with TTR in human plasma after ingestion in physiological amounts. Some hydrophobic compounds with yellow color may bind to human TTR in the plasma. However, this association needs to be further proved by showing specificity. The study provides a new approach for carotenoid-binding protein studies using a stable isotope tracer method combined with the high precision of GCC-IRMS. The mechanism of selective transport, uptake, and accumulation of lutein in human macula remain to be determined.

  19. Degenerate four-photon probing of the kinetics of a nonlinear response of high-temperature superconductors in pump-probe spectroscopy

    SciTech Connect (OSTI)

    Bobyrev, Yu V; Petnikova, V M; Rudenko, K V; Shuvalov, Vladimir V [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2005-08-31T23:59:59.000Z

    It is shown that the spectral-temporal and temperature 'anomalies' of the kinetics of reflection and transmission coefficients of high-temperatures superconductors (HTSCs) at high 'impact' excitation levels have direct analogies also in the case when the instant state of samples is probed by using the self-diffraction of probe pulses made coincident in time and propagating at an angle to each other. The possibility of using the transient modification of the method of degenerate four-photon spectroscopy for the HTSC diagnostics substantially expands the scope of experiments that can confirm or refute the correctness of the model based on the consideration of the contribution of interband electronic transitions to the response of an excited HTSC film with the 'frozen' energy gap. (nonlinear optical phenomena)

  20. Fig. 1: (a) Conventional dual-pump degenerate PSA using a straight HNLF: phase regeneration effect varies with polarization alignment between BPSK signal and two phase-locked pumps. (b) Polarization-diversity PSA

    E-Print Network [OSTI]

    Touch, Joe

    Fig. 1: (a) Conventional dual-pump degenerate PSA using a straight HNLF: phase regeneration effect varies with polarization alignment between BPSK signal and two phase-locked pumps. (b) Polarization. Pump 2Signal Pump 1 HNLF Impaired by phase noise I Q Single-polarization BPSK signal Pump1 (Phase

  1. Age-related breeding biology of the redhead duck in southwestern Manitoba

    E-Print Network [OSTI]

    Johnson, David John

    1978-01-01T23:59:59.000Z

    scaup (Qt~h a affinis) at Yellowknife, Northwest Territories (Trauger 1971:48- 49). For North American members of ~A th a, information regarding migra- tional homing is limited. Mendall (1958) and Coulter and Miller (1968) reported observations...

  2. Age-related comparison of superoxide production by canine neutrophilic polymorphonuclear leukocytes

    E-Print Network [OSTI]

    Hanson, Thomas Dale

    1983-01-01T23:59:59.000Z

    LIST OF FIGURES F1gure No. T1tle Page Figure 1. Figure 2. F1gure 3. Figure 4. Temporal traces of 02 dependent cytochrome C 18 reduction by CE-Con )( st1mulated canine neutro- phils from a selected group of 12 young (0. 5 to 6 years) and 26 aged... (2, 15, 64). Phagocytically stimulated neutro- phils synthes1ze abundant quantities of 02 . In vitro and in viva observations suggest that e1ther 02- and/or H202, or a product of their interaction, is 1nvolved in the microbic1dal event (2, 64...

  3. alkanes and alkenes. Queen larvae showed lower variations in age-related differences.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    que la quantité absolue de substances odorantes (et hydrocarbures) augmentait avec l'âge des larves et). On a identifié 62 hydrocarbures (alcanes, alcènes, dialcènes, alcanes méthy- liques et alcanes diméthyliques, N = 6) du bou- quet odorant total. Dans une analyse factorielle portant sur 28 hydrocarbures (il n

  4. Hyperactive p53 leads to age-related phenotypes in mice model

    E-Print Network [OSTI]

    Ou, Linda Ye

    2009-01-01T23:59:59.000Z

    Senescence through p53- and pRB-mediated Pathways. Journalof retinoblastoma gene product (pRB), thus delayingdissociation of E2F-pRB complex and S-phase entry of the

  5. age-related nerve decline: Topics by E-print Network

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

    of Caribbean Eusocial Shrimp J. Emmett Duffy1 *, Kenneth S. Macdonald Rubenstein, Dustin R. 432 J Epidemiol Community Health . Author manuscript Socioeconomic position and...

  6. Exploring Age-Related Environmental Attitudes in the Context of Wood Product Certification

    E-Print Network [OSTI]

    Wu, Qinglin

    environmental standards, which companies could follow in the growing and harvesting of timber. Those that follow including environmental organizations, retailers and wood product companies are interested in developing'. Companies that certify their products encourage environmentally minded consumers to buy their products over

  7. age-related plumage differences: Topics by E-print Network

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

    with timing of dispersal and plumage morph in a sedentary Environmental Sciences and Ecology Websites Summary: -individual differences may arise due to polymorphic genes...

  8. aging-related cognitive dysfunction: Topics by E-print Network

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

    sequencing). The paradigm was developed so that performance 25 A disembodied mind : the role of dysfunctional simulation systems in the social and cognitive deficits of...

  9. Age-related sensitivity to task-­related modulation of language-processing networks

    E-Print Network [OSTI]

    Davis, S. W.; Zhuang, J.; Wright, P.; Tyler, L. K.

    2014-08-27T23:59:59.000Z

      &   Preprocessing.   Functional,   T2*-­?weighted   echo-­?planar   images   (EPI)   were   acquired  using  a  Siemens  3T  Tim  Trio  MRI   scanner   (Siemens  Medical   Solutions,  Camberley,  UK)  at   the  MRC... the accept- ability judgement task during scanning. 2.4. MRI acquisition and preprocessing Functional, T2*-weighted echo-planar images (EPI) were acquired using a Siemens 3T Tim Trio MRI scanner (Siemens Medical Solutions, Camberley, UK) at the MRC Cognition...

  10. age-related cortical cataract: Topics by E-print Network

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

    Cortical systems for local and global integration in discourse comprehension Giovanna Egidi a, Biology and Medicine Websites Summary: Cortical systems for local and global...

  11. age-related hearing impairment: Topics by E-print Network

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

    of Temporally Processed Speech by Listeners with Hearing Impairment Lauren Calandruccio (SPC), for a group of listeners with varying degrees of sensorineural hearing loss. SPC is...

  12. GABAergic systems in a model of age-related cognitive impairment

    E-Print Network [OSTI]

    LaSarge, Candi Lynn

    2012-07-16T23:59:59.000Z

    cohort of young and aged rats was characterized in an odor discrimination task. Similar to aged rat water maze performance, some aged rats performed odor learning discrimination problems on par with the young cohort (i.e. aged-unimpaired) and some aged...

  13. age-related lh surge: Topics by E-print Network

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

    RELEASE FOLLOWING STEROID MANIPULATIONS Physics Websites Summary: ) and prolactin (PRL) levels have been studied in groups of immature normal male and female Wistar rats and...

  14. Age-Related Changes in the Spontaneous Motor Rhythms of the

    E-Print Network [OSTI]

    Liu, Taosheng

    , Department of Psychology, Bowling Green State University, Bowling Green, Ohio, USA The present study examined of Psychology, Bowling Green State University, Bowling Green, OH 43403, USA. E-mail: mcauley

  15. Age-related disruptions in circadian timing: evidence for "split" activity rhythms in the SAMP8

    E-Print Network [OSTI]

    Liu, Taosheng

    for Neuroscience, Mind, and Behavior, Department of Psychology, Bowling Green State University, Bowling Green, OH

  16. attenuates age-related decrements: Topics by E-print Network

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

    where no assembled, virialized clusters are detected either in the optical or X-ray wave-band. Invoking quasar outflows, we argue that both thermal and kinematic decrements...

  17. age-related white matter: Topics by E-print Network

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

    According to this hypothesis, ... Tsenkina, Yanina 2013-07-06 4 Is Galactic Dark Matter White ? Astrophysics (arXiv) Summary: We calculate the expected white dwarf luminosity...

  18. Solvable model of quantum phase transitions and the symbolic-manipulation-based study of its multiply degenerate exceptional points and of their unfolding

    SciTech Connect (OSTI)

    Znojil, Miloslav, E-mail: znojil@ujf.cas.cz

    2013-09-15T23:59:59.000Z

    It is known that the practical use of non-Hermitian (i.e., typically, PT-symmetric) phenomenological quantum Hamiltonians H?H{sup †} requires an efficient reconstruction of an ad hoc Hilbert-space metric ?=?(H) which would render the time-evolution unitary. Once one considers just the N-dimensional matrix toy models H=H{sup (N)}, the matrix elements of ?(H) may be defined via a coupled set of N{sup 2} polynomial equations. Their solution is a typical task for computer-assisted symbolic manipulations. The feasibility of such a model-completion construction is illustrated here via a discrete square well model H=p{sup 2}+V endowed with a k-parametric close-to-the-boundary interaction V. The model is shown to possess (possibly, multiply degenerate) exceptional points marking the phase transitions which are attributable, due to the exact solvability of the model at any N

  19. Non-perturbative quantum effects in stringy degenerate geometries: Vacuum created pair of $(D{\\bar D})_3$-brane by a two form

    E-Print Network [OSTI]

    K. Priyabrat Pandey; Abhishek K. Singh; Sunita Singh; Supriya Kar

    2015-04-26T23:59:59.000Z

    We obtain axionic charged primordial black holes on a vacuum created gravitational pair of $(3{\\bar 3})$-brane by the Kalb-Ramond field on a $D_4$-brane in presence of a background open string metric. The new geometries on an emergent pair of $(3{\\bar 3})$-brane universe is shown to be influenced by the non-perturbative quantum effects underlying a geometric torsion in a second order formalism. The presence of small extra dimensions transverse to the pair in the formalism ensures dynamical scalar fields hidden to a $3$-brane or an anti 3-brane universe. We investigate the non-perturbative quantum vacua for their characteristic properties to explain the accelerated expansion of our universe. Interestingly the emergent brane universe is shown to possess its origin in a degenerate stringy de Sitter vacua at an early epoch. A non-perturbative $D_p$-brane world volume correction for $p < 3$ is worked out to explain some of the quantum effects underlying a quintessence axion in the string-brane setup. Our analysis reveals that a $D$-instanton can be a potential candidate to source the dark energy in our brane universe.

  20. Degenerate and critical Bloch branes

    SciTech Connect (OSTI)

    Souza Dutra, A. de [Abdus Salam ICTP, Strada Costiera 11, Trieste, I-34100 Italy (Italy); UNESP-Campus de Guaratingueta-DFQ, Departmento de Fisica e Quimica, 12516-410 Guaratingueta SP Brasil (Brazil); Amaro de Faria, A. C. Jr.; Hott, M. [UNESP-Campus de Guaratingueta-DFQ, Departmento de Fisica e Quimica, 12516-410 Guaratingueta SP Brasil (Brazil)

    2008-08-15T23:59:59.000Z

    In the last few years a number of works reported the appearance of thick branes with internal structure, induced by the parameter which controls the interaction between two scalar fields coupled to gravity in (4,1) dimensions in warped space-time with one extra dimension. Here we show that one can implement the control over the brane thickness without needing to change the potential parameter. On the contrary, this is going to be done by means of the variation of a parameter associated with the domain wall degeneracy. We also report the existence of novel and qualitatively different solutions for a critical value of the degeneracy parameter, which could be called critical Bloch branes.

  1. High field magnetotransport and point contact Andreev reflection measurements on CuCr{sub 2}Se{sub 4} and CuCr{sub 2}Se{sub 3}Br—Degenerate magnetic semiconductor single crystals

    SciTech Connect (OSTI)

    Borisov, K., E-mail: borisovk@tcd.ie; Coey, J. M. D.; Stamenov, P. [School of Physics and CRANN, Trinity College, Dublin 2 (Ireland); Alaria, J. [Department of Physics, University of Liverpool, Liverpool L69 7ZE (United Kingdom)

    2014-05-07T23:59:59.000Z

    Single crystals of the metallically degenerate fully magnetic semiconductors CuCr{sub 2}Se{sub 4} and CuCr{sub 2}Se{sub 3}Br have been prepared by the Chemical Vapour Transport method, using either Se or Br as transport agents. The high-quality, millimetre-sized, octahedrally faceted, needle- and platelet-shaped crystals are characterised by means of high field magnetotransport (?{sub 0}H? 14?T) and Point Contact Andreev Reflection. The relatively high spin polarisation observed |P|>0.56, together with the relatively low minority carrier effective mass of 0.25 m{sub e}, and long scattering time  10{sup ?13}?s, could poise these materials for integration in low- and close-to-room temperature minority injection bipolar heterojunction transistor demonstrations.

  2. Age-Related Changes in Vestibular Evoked Myogenic Potentials and Dynamic Visual Acuity at Near and Far Distances

    E-Print Network [OSTI]

    Tourtillott, Brandon Michael

    2009-09-03T23:59:59.000Z

    Morphological changes in the vestibular system associated with aging are well documented, but the ability to measure these changes clinically has been limited. Two such tests that have been useful for this purpose are ...

  3. Age-Related Effects on Markers of Inflammation and Cartilage Metabolism in Response to an Intra-Articular Lipopolysaccharide Challenge

    E-Print Network [OSTI]

    Kahn, Meredith K

    2014-11-25T23:59:59.000Z

    other amino acids, 22% of which are proline and 4-hydroxyproline, respectively (Platt, 1996). Fibril formation is critical for achieving the physiologic strength of the collagen framework (Ray et al., 1996). Type II collagen is synthesized... extensions serving as useful markers to monitor collagen synthesis. As collagen is synthesized, the newly released type II collagen molecules associate in the matrix to form the collagen fibrils by means of intermolecular cross-linking (Platt, 1996...

  4. Lifespan extension and delay of age-related functional decline caused by Rhodiola rosea depends on dietary macronutrient balance

    E-Print Network [OSTI]

    Gospodaryov, Dmytro V; Yurkevych, Ihor S; Jafari, Mahtab; Lushchak, Volodymyr I; Lushchak, Oleh V

    2013-01-01T23:59:59.000Z

    enhance resistance to heat stress, heavy metals, and redox-by mena- dione, and heat stress. Along with mobility andTo evaluate resistance to heat stress, single flies were

  5. The sensitive period for language acquisition: The role of age related differences in cognitive and neural function

    E-Print Network [OSTI]

    Finn, Amy Sue

    2010-01-01T23:59:59.000Z

    S. -A. , Fiebach, C. J. , Kempe, V. , & Friederici, A. D. (1995; Rüschemeyer, Fiebach, Kempe, & Friederici, 2005;

  6. Adolescents with current major depressive disorder show dissimilar patterns of age-related differences in ACC and thalamus

    E-Print Network [OSTI]

    Hagan, Cindy C.; Graham, Julia M. E.; Tait, Roger; Widmer, Barry; van Nieuwenhuizen, Adrienne O.; Ooi, Cinly; Whitaker, Kirstie J.; Simas, Tiago; Bullmore, Edward T.; Lennox, Belinda R.; Sahakian, Barbara J.; Goodyer, Ian M.; Suckling, John

    2015-01-07T23:59:59.000Z

    , we estimate our power for detecting true significant effects at 0.70. 2.2. Structural MRI (sMRI) data acquisition MR images of all subjects were acquired by a 3.0 Tesla Magnetom Trio Tim scanner (Siemens, Surrey, England) fitted with a quadrature...

  7. Review of Recent Aging-Related Degradation Occurrences of Structures and Passive Components in U.S. Nuclear Power Plants

    SciTech Connect (OSTI)

    Nie,J.; Braverman, J.; Hofmayer, C.; Choun, Y.-S.; Kim, M.K.; Choi, I.-K.

    2009-04-02T23:59:59.000Z

    The Korea Atomic Energy Research Institute (KAERI) and Brookhaven National Laboratory (BNL) are collaborating to develop seismic capability evaluation technology for degraded structures and passive components (SPCs) under a multi-year research agreement. To better understand the status and characteristics of degradation of SPCs in nuclear power plants (NPPs), the first step in this multi-year research effort was to identify and evaluate degradation occurrences of SPCs in U.S. NPPs. This was performed by reviewing recent publicly available information sources to identify and evaluate the characteristics of degradation occurrences and then comparing the information to the observations in the past. Ten categories of SPCs that are applicable to Korean NPPs were identified, comprising of anchorage, concrete, containment, exchanger, filter, piping system, reactor pressure vessel, structural steel, tank, and vessel. Software tools were developed to expedite the review process. Results from this review effort were compared to previous data in the literature to characterize the overall degradation trends.

  8. In Vivo Measurement of Age-Related Stiffening in the Crystalline Lens by Brillouin Optical Microscopy

    E-Print Network [OSTI]

    Scarcelli, Giuliano

    The biophysical and biomechanical properties of the crystalline lens (e.g., viscoelasticity) have long been implicated in accommodation and vision problems, such as presbyopia and cataracts. However, it has been difficult ...

  9. Age-related hyperkyphosis, independent of spinal osteoporosis, is associated with impaired mobility in older community-dwelling women

    E-Print Network [OSTI]

    Katzman, W. B.; Vittinghoff, E.; Kado, D. M.

    2011-01-01T23:59:59.000Z

    independent of spinal osteoporosis, is associated withun- derlying spinal osteoporosis and vertebral fractures,independent of spinal osteoporosis, is associated with

  10. accidental macular injury: Topics by E-print Network

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

    activity in the ADRIA project concerns the performance of numerical simulations of the brain response to human head loading during car Verhoeve Bovendeerd Wismans 78 Effect of...

  11. THE POST-MERGER MAGNETIZED EVOLUTION OF WHITE DWARF BINARIES: THE DOUBLE-DEGENERATE CHANNEL OF SUB-CHANDRASEKHAR TYPE Ia SUPERNOVAE AND THE FORMATION OF MAGNETIZED WHITE DWARFS

    SciTech Connect (OSTI)

    Ji Suoqing; Fisher, Robert T. [University of Massachusetts Dartmouth, Department of Physics, 285 Old Westport Road, North Dartmouth, MA 02740 (United States); Garcia-Berro, Enrique [Departament de Fisica Aplicada, Universitat Politecnica de Catalunya, c/Esteve Terrades, 5, E-08860 Castelldefels (Spain); Tzeferacos, Petros; Jordan, George; Lee, Dongwook [Center for Astrophysical Thermonuclear Flashes, The University of Chicago, Chicago, IL 60637 (United States); Loren-Aguilar, Pablo [School of Physics, University of Exeter, Stocker Road, Exeter EX4 4QL (United Kingdom); Cremer, Pascal [Bethe Center for Theoretical Physics, Universitaet Bonn, Nussallee 12, D-53115 Bonn (Germany); Behrends, Jan [Fachbereich Physik, Freie Universitaet Berlin, Arnimallee 14, D-14195 Berlin (Germany)

    2013-08-20T23:59:59.000Z

    Type Ia supernovae (SNe Ia) play a crucial role as standardizable cosmological candles, though the nature of their progenitors is a subject of active investigation. Recent observational and theoretical work has pointed to merging white dwarf binaries, referred to as the double-degenerate channel, as the possible progenitor systems for some SNe Ia. Additionally, recent theoretical work suggests that mergers which fail to detonate may produce magnetized, rapidly rotating white dwarfs. In this paper, we present the first multidimensional simulations of the post-merger evolution of white dwarf binaries to include the effect of the magnetic field. In these systems, the two white dwarfs complete a final merger on a dynamical timescale, and are tidally disrupted, producing a rapidly rotating white dwarf merger surrounded by a hot corona and a thick, differentially rotating disk. The disk is strongly susceptible to the magnetorotational instability (MRI), and we demonstrate that this leads to the rapid growth of an initially dynamically weak magnetic field in the disk, the spin-down of the white dwarf merger, and to the subsequent central ignition of the white dwarf merger. Additionally, these magnetized models exhibit new features not present in prior hydrodynamic studies of white dwarf mergers, including the development of MRI turbulence in the hot disk, magnetized outflows carrying a significant fraction of the disk mass, and the magnetization of the white dwarf merger to field strengths {approx}2 Multiplication-Sign 10{sup 8} G. We discuss the impact of our findings on the origins, circumstellar media, and observed properties of SNe Ia and magnetized white dwarfs.

  12. Preprocessing and Reduction for Degenerate Semidefinite Programs

    E-Print Network [OSTI]

    2011-02-18T23:59:59.000Z

    Feb 18, 2011 ... Sensitivity analysis and backward stability results are presented in Section 4. .... Applications that exploit the failure of Slater's CQ for SDP ...

  13. Oscillations fortes sur un champ lineairement degenere

    E-Print Network [OSTI]

    Métivier, Guy

    .1 Solutions BKW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 3.2 Stabilit´e hyperbolique . . . . . . . . . . . . . . . . . . . . . . . . . . 17 3.3 Instabilit´e hyperbolique . . . . . . . . . . . . . . . . . . . . . . . . . 19 4 Solutions BKW

  14. ITAR: A modified TAR method to determine depth dose distribution for an ophthalmic device that performs kilovoltage x-ray pencil-beam stereotaxy

    SciTech Connect (OSTI)

    Hanlon, Justin, E-mail: jhanlon@orayainc.com; Chell, Erik; Firpo, Michael; Koruga, Igor [Oraya Therapeutics, Inc., Newark, California 94560 (United States)] [Oraya Therapeutics, Inc., Newark, California 94560 (United States)

    2014-02-15T23:59:59.000Z

    Purpose: New technology has been developed to treat age-related macular degeneration (AMD) using 100 kVp pencil-beams that enter the patient through the radio-resistant sclera with a depth of interest between 1.6 and 2.6 cm. Measurement of reference and relative dose in a kilovoltage x-ray beam with a 0.42 cm diameter field size and a 15 cm source to axis distance (SAD) is a challenge that is not fully addressed in current guidelines to medical physicists. AAPM's TG-61 gives dosimetry recommendations for low and medium energy x-rays, but not all of them are feasible to follow for this modality. Methods: An investigation was conducted to select appropriate equipment for the application. PTW's Type 34013 Soft X-Ray Chamber (Freiburg, Germany) and CIRS's Plastic Water LR (Norfolk, VA) were found to be the best available options. Attenuation curves were measured with minimal scatter contribution and thus called Low Scatter Tissue Air Ratio (LSTAR). A scatter conversion coefficient (C{sub scat}) was derived through Monte Carlo radiation transport simulation using MCNPX (LANL, Los Alamos, NM) to quantify the difference between a traditional TAR curve and the LSTAR curve. A material conversion coefficient (C{sub mat}) was determined through experimentation to evaluate the difference in attenuation properties between water and Plastic Water LR. Validity of performing direct dosimetry measurements with a source to detector distance other than the treatment distance, and therefore a different field size due to a fixed collimator, was explored. A method—Integrated Tissue Air Ratio (ITAR)—has been developed that isolates each of the three main radiological effects (distance from source, attenuation, and scatter) during measurement, and integrates them to determine the dose rate to the macula during treatment. Results: LSTAR curves were determined to be field size independent within the range explored, indicating that direct dosimetry measurements may be performed with a source to detector distance of 20 cm even though the SAD is 15 cm during treatment. C{sub scat} varied from 1.102 to 1.106 within the range of depths of interest. The experimental variance among repeated measurements of C{sub mat} was larger than depth dependence, so C{sub mat} was estimated as1.019 for all depths of interest. Conclusions: Equipment selection, measurement techniques, and formalism for the determination of dose rate to the macula during stereotaxy for AMD have been determined and are strongly recommended by the authors of this paper to be used by clinical medical physicists.

  15. Dosimetric properties of a proton beamline dedicated to the treatment of ocular disease

    SciTech Connect (OSTI)

    Slopsema, R. L., E-mail: rslopsema@floridaproton.org; Mamalui, M.; Yeung, D.; Malyapa, R.; Li, Z. [University of Florida Proton Therapy Institute, 2015 North Jefferson Street, Jacksonville, Florida 32205 (United States)] [University of Florida Proton Therapy Institute, 2015 North Jefferson Street, Jacksonville, Florida 32205 (United States); Zhao, T. [Department of Radiation Oncology, Washington University School of Medicine, 4921 Parkview Place, St. Louis, Missouri 63110 (United States)] [Department of Radiation Oncology, Washington University School of Medicine, 4921 Parkview Place, St. Louis, Missouri 63110 (United States)

    2014-01-15T23:59:59.000Z

    Purpose: A commercial proton eyeline has been developed to treat ocular disease. Radiotherapy of intraocular lesions (e.g., uveal melanoma, age-related macular degeneration) requires sharp dose gradients to avoid critical structures like the macula and optic disc. A high dose rate is needed to limit patient gazing times during delivery of large fractional dose. Dose delivery needs to be accurate and predictable, not in the least because current treatment planning algorithms have limited dose modeling capabilities. The purpose of this paper is to determine the dosimetric properties of a new proton eyeline. These properties are compared to those of existing systems and evaluated in the context of the specific clinical requirements of ocular treatments. Methods: The eyeline is part of a high-energy, cyclotron-based proton therapy system. The energy at the entrance of the eyeline is 105 MeV. A range modulator (RM) wheel generates the spread-out Bragg peak, while a variable range shifter system adjusts the range and spreads the beam laterally. The range can be adjusted from 0.5 up to 3.4 g/cm{sup 2}; the modulation width can be varied in steps of 0.3 g/cm{sup 2} or less. Maximum field diameter is 2.5 cm. All fields can be delivered with a dose rate of 30 Gy/min or more. The eyeline is calibrated according to the IAEA TRS-398 protocol using a cylindrical ionization chamber. Depth dose distributions and dose/MU are measured with a parallel-plate ionization chamber; lateral profiles with radiochromic film. The dose/MU is modeled as a function of range, modulation width, and instantaneous MU rate with fit parameters determined per option (RM wheel). Results: The distal fall-off of the spread-out Bragg peak is 0.3 g/cm{sup 2}, larger than for most existing systems. The lateral penumbra varies between 0.9 and 1.4 mm, except for fully modulated fields that have a larger penumbra at skin. The source-to-axis distance is found to be 169 cm. The dose/MU shows a strong dependence on range (up to 4%/mm). A linear increase in dose/MU as a function of instantaneous MU rate is observed. The dose/MU model describes the measurements with an accuracy of ±2%. Neutron dose is found to be 146 ± 102 ?Sv/Gy at the contralateral eye and 19 ± 13 ?Sv/Gy at the chest. Conclusions: Measurements show the proton eyeline meets the requirements to effectively treat ocular disease.

  16. Trajectory-following methods for large-scale degenerate convex ...

    E-Print Network [OSTI]

    2011-09-02T23:59:59.000Z

    Sep 2, 2011 ... ming is contained within these problem classes. (See [1,48] for descriptions and .... “work horse” of our method. We note that Zhang and Zhang ...

  17. PML in the brain: From development to degeneration

    E-Print Network [OSTI]

    Korb, E; Finkbeiner, SM

    2013-01-01T23:59:59.000Z

    1? (PP1?) and retinoblastoma protein (pRB), which resultsin dephosphorylation of pRB and controls neuronal

  18. A Solvable Two-Dimensional Degenerate Singular Stochastic Control Problem

    E-Print Network [OSTI]

    Glendinning, Paul

    . The optimisation is motivated by a storage-consumption model in an electricity market, and features a stochastic investment; electricity market. MSC2010 subsject classification: 91B70, 93E20, 60G40, 49L20. 1 Introduction of electricity markets. Here the first component of the state process is the electricity spot price, represented

  19. A minimum problem with free boundary for a degenerate quasilinear ...

    E-Print Network [OSTI]

    2005-03-04T23:59:59.000Z

    Feb 8, 2005 ... By the strong minimum principle, w0 = 0 in B5/8, since w0 ? 0 and w0(0) ..... 4.7 in [2] and pp. 19–20 in [3]; see also our proof of Theorem 5.1.

  20. Degenerate resistive switching and ultrahigh density storage in resistive memory

    SciTech Connect (OSTI)

    Lohn, Andrew J., E-mail: drewlohn@gmail.com; Mickel, Patrick R., E-mail: prmicke@sandia.gov; James, Conrad D.; Marinella, Matthew J. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

    2014-09-08T23:59:59.000Z

    We show that in tantalum oxide resistive memories, activation power provides a multi-level variable for information storage that can be set and read separately from the resistance. These two state variables (resistance and activation power) can be precisely controlled in two steps: (1) the possible activation power states are selected by partially reducing resistance, then (2) a subsequent partial increase in resistance specifies the resistance state and the final activation power state. We show that these states can be precisely written and read electrically, making this approach potentially amenable for ultra-high density memories. We provide a theoretical explanation for information storage and retrieval from activation power and experimentally demonstrate information storage in a third dimension related to the change in activation power with resistance.

  1. Studies of a Quantum Degenerate Fermionic Lithium Gas Zoran Hadzibabic

    E-Print Network [OSTI]

    that the lifetime of the strongly interacting system is long enough to observe a superfluid transition in the future of strongly interacting spin-mixtures of ultracold fermions. We have cooled a magnetically trapped spin-polarized 6Li Fermi gas into quantum degen- eracy by sympathetic cooling with bosonic 23Na. In order to do

  2. Developmental Mechanisms for Retinal Degeneration in the Blind Cavefish

    E-Print Network [OSTI]

    Jeffery, William R.

    , and Vax1, together with the differen- tiation marker GAD65. We show that eye development is retarded in CF; eye; proliferation; cell death; Shh; Fgf8; Pax6; LIM-homeodomain; Vax1; GABA; teleost; fish Vertebrate

  3. Magnetic Fields in Quantum Degenerate Systems and in Vacuum

    E-Print Network [OSTI]

    H. Perez Rojas; E. Rodriguez Querts

    2006-12-28T23:59:59.000Z

    We consider self-magnetization of charged and neutral vector bosons bearing a magnetic moment in a gas and in vacuum. For charged vector bosons (W bosons) a divergence of the magnetization in both the medium and the electroweak vacuum occurs for the critical field B=B_{wc}=m_{w}^{2}/e. For B>B_{wc} the system is unstable. This behavior suggests the occurrence of a phase transition at B=B_{c}, where the field is self-consistently maintained. This mechanism actually prevents $B$ from reaching the critical value B_{c}. For virtual neutral vector bosons bearing an anomalous magnetic moment, the ground state has a similar behavior for B=B_{nbc}=m_{nb}^{2}/q . The magnetization in the medium is associated to a Bose-Einstein condensate and we conjecture a similar condensate occurs also in the case of vacuum. The model is applied to virtual electron-positron pairs bosonization in a magnetic field B \\sim B_{pc}\\lesssim 2m_{e}^{2}/e, where m_e is the electron mass. This would lead also to vacuum self-magnetization in QED, where in both cases the symmetry breaking is due to a condensate of quasi-massless particles.

  4. Tools for primal degenerate linear programs: IPS, DCA, and PE

    E-Print Network [OSTI]

    2014-10-01T23:59:59.000Z

    the selection of a compatible variable to enter the basis ensures a nondegenerate pivot, PE .... At the heart of this framework lies the search for so-

  5. Row-Reduced Column Generation for Degenerate Master Problems

    E-Print Network [OSTI]

    2013-02-06T23:59:59.000Z

    Feb 5, 2013 ... node of a search tree, and often produces strong dual bounds. ... In linear algebra terms, we work with a projection ... enter the current basis.

  6. alleviates radiation-induced degeneration: Topics by E-print...

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

    solar and atmospheric neutrino oscillation, some of them can also induce neutrinoless double beta decay and mu- -- e+ conversion in nuclei large enough to be potentially...

  7. Contemporary Mathematics Local Estimates for Solutions to Singular and Degenerate

    E-Print Network [OSTI]

    O'Leary, Michael

    Parabolic Equations Mike O'Leary 1. Introduction and Results We shall obtain Lq,loc(T ) and L-8218-1196-7-03551-9 c 1999 American Mathematical Society 241 #12;2 MIKE O'LEARY Theorem 1. Let u be a weak solution

  8. Supplementary Information Primary amines protect against retinal degeneration in

    E-Print Network [OSTI]

    Palczewski, Krzysztof

    µm column, linear gradient of acetonitrile in water (0­ 100% acetonitrile over 20 min at a flow rate) in a linear gradient of acetonitrile in water (80 ­ 100% acetonitrile over 20 min at a flow rate of 1.5 ml/min). Both solvents contained 0.05% trifluoroacetic acid (TFA). HPLC elution: 9.0 min. UV/Vis (acetonitrile

  9. Lipschitz conformal immersions from degenerating Riemann surfaces with L2

    E-Print Network [OSTI]

    Rivière, Tristan

    (I.1) we can define the Gauss map as being the following measurable map in L () taking values and |dn|2 g dvolg canonical metric gRm of Rm . This energy E can be hence seen as being the Dirichlet Energy of the Gauss map n with respect to the induced

  10. Non-Invasive Detection of Early Retinal Neuronal Degeneration by Ultrahigh Resolution Optical Coherence

    E-Print Network [OSTI]

    Martin, Ralph R.

    Coherence Tomography Debbie Tudor1 , Vedran Kajic´4 , Sara Rey3 , Irina Erchova1,3 , Boris Povazay4 , Bernd Hofer4 , Kate A. Powell3 , David Marshall2 , Paul L. Rosin2 , Wolfgang Drexler4 , James E. Morgan1,5 * 1

  11. Observation of Degenerate One-Dimensional Sub-Bands in Cylindrical InAs Nanowires

    E-Print Network [OSTI]

    Javey, Ali

    . The p+ Si substrate is used as the global back-gate. The source (S) and drain (D) contacts were defined-sectional structure of a representative back-gated InAs NW device is shown in Figure 1a. The InAs NWs used, 2012 Figure 1. (a) Schematic of the cross-sectional structure of a representative back

  12. Multistability and transition to chaos in the degenerate Hamiltonian system with weak nonlinear dissipative perturbation

    E-Print Network [OSTI]

    E. V. Felk; A. P. Kuznetsov; A. V. Savin

    2013-11-13T23:59:59.000Z

    The effect of small nonlinear dissipation on the dynamics of system with stochastic web which is linear oscillator driven by pulses is studied. The scenario of coexisting attractors evolution with the increase of nonlinear dissipation is revealed. It is shown that the period-doubling transition to chaos is possible only for third order resonance and only hard transitions can be seen for all other resonances.

  13. Spin effect on parametric decay of oblique Langmuir wave in degenerate magneto-plasmas

    SciTech Connect (OSTI)

    Shahid, M. [Salam Chair in Physics, Government College University, Lahore-54000 (Pakistan) [Salam Chair in Physics, Government College University, Lahore-54000 (Pakistan); Department of Physics, Government College University, Lahore-54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, Government College University, Lahore-54000 (Pakistan)] [Salam Chair in Physics, Government College University, Lahore-54000 (Pakistan)

    2013-08-15T23:59:59.000Z

    The electron spin ?1/2 effects on the parametric decay instability of oblique Langmuir wave into low-frequency electromagnetic shear Alfven wave and Left-Handed Circularly Polarized wave (LHCP) has been investigated in detail, in an electron-ion quantum plasma immersed in the uniform external magnetic field. Incorporating the quantum effects due to electron spin, Fermi pressure and Bohm potential term, the quantum magneto-hydrodynamic (QMHD) model has been used to investigate the linear and nonlinear response of the plasma species for three-wave coupling interaction in a quantum magneto-plasmas. Nonlinear dispersion relations and growth rate of the problem have been derived analytically. It has been shown that the spin of electrons has considerable effect on the growth rate of parametric instability problem even when the external magnetic field B{sub 0} is below the quantum critical magnetic field strength B{sub Q}=4.4138×10{sup 13}G.

  14. A New Approach for the Numerical Solution of Diffusion Equations with Variable and Degenerate Mobility

    E-Print Network [OSTI]

    Bigelow, Stephen

    plays a prominent role in phase field models of fluids and soft materials but the methodology has a more separation that occurs in an isothermal binary system when a spatially uniform mixture is quenched below

  15. LiNaK : multi-species apparatus for the study of ultracold quantum degenerate mixtures

    E-Print Network [OSTI]

    Santiago González, Ibon

    2012-01-01T23:59:59.000Z

    This thesis describes the construction of a versatile apparatus to study ultracold quantum mixtures capable of simultaneously cooling fermionic ?Li and ??K, as well as the bosonic ?¹K. The main features of the experimental ...

  16. Characterization of RPGR Variants and Their Role in Inherited Retinal Degeneration

    E-Print Network [OSTI]

    Wright, Rachel

    2012-10-19T23:59:59.000Z

    a gene between CYBB and OTC in Xp21.1 with 19 constitutive exons spanning 60kb of genomic DNA. The locus encodes a ubiquitously expressed protein, hereafter identified as RPGRex1-19, with a predicted molecular mass of approximately 90k... domains between the RCC1-homologous domain and ORF15 maintain a physiological role in the retina (28). Interestingly, four other known mutations within the RCC1- homologous domain (G173R; 786-787delTG; C469+1G>T, intron 5; c.619+9del, intron 6), result...

  17. Research Recruiting Endogenous Tissue Stem Cells to Repair Injury and Degeneration

    SciTech Connect (OSTI)

    Peterson, Daniel A. [Rosalind Franklin University of Medicine and Science

    2014-10-22T23:59:59.000Z

    This report lists bibliographic information about meeting papers and journal articles resulting from this work, and basic information on new grant applications that this work was used to support.

  18. Non-collinear and non-degenerate polarization-entangled photon

    E-Print Network [OSTI]

    Sergienko, Alexander

    efficiency measurements using correlated photons", Metrologia, 32, 479-483 (1995). 5. D. Branning, A. L

  19. Data embedding employing degenerate clusters of data having differences less than noise value

    DOE Patents [OSTI]

    Sanford, M.T. II; Handel, T.G.

    1998-10-06T23:59:59.000Z

    A method of embedding auxiliary information into a set of host data, such as a photograph, television signal, facsimile transmission, or identification card. All such host data contain intrinsic noise, allowing pixels in the host data which are nearly identical and which have values differing by less than the noise value to be manipulated and replaced with auxiliary data. As the embedding method does not change the elemental values of the host data, the auxiliary data do not noticeably affect the appearance or interpretation of the host data. By a substantially reverse process, the embedded auxiliary data can be retrieved easily by an authorized user. 35 figs.

  20. Role of Pam16's degenerate J domain in protein import across the mitochondrial inner membrane

    E-Print Network [OSTI]

    Craig, Elizabeth A

    Patrick R. D'Silva*, Brenda Schilke*, William Walter, and Elizabeth A. Craig Department of Biochemistry domain to stim- ulate Ssc1's ATPase domain, and (iii) the innately lower stimulatory activity of the Pam-terminal regions. In addition, the C-terminal region of Pam16 has significant sequence similarity to Pam18's C

  1. Phospholipase A2 inhibitors protect against prion and Abeta mediated synapse degeneration

    E-Print Network [OSTI]

    Bate, Clive; Tayebi, Mourad; Williams, Alun

    2010-04-08T23:59:59.000Z

    's F12 con- taining 5% FCS, 0.35% glucose, 0.025% trypsin, and 0.1% type IV collagenase. After 30 minutes at 37°C, the cells were triturated again and the cell suspension was passed through a 100 ?M cell strainer. Cells were collected by centrifugation...

  2. Non-degenerate magnetic alignment of self-assembled mesophases Pawel W. Majewski* Chinedum O. Osuji

    E-Print Network [OSTI]

    Haller, Gary L.

    and photonic crystals2­4 to high-density storage media5,6 and templates for materials synthesis.7­9 In many) offer promise as a flexible tool for nanostructure alignment in these systems. They circumvent be conveniently applied over macroscopic length scales (> 10 cm) and to geometries or devices that are ill

  3. Signs of the Degenerate Age: the Desecration of Chorten and Lhakhang in Bhutan

    E-Print Network [OSTI]

    Whitecross, Richard W

    2000-01-01T23:59:59.000Z

    he stated “if evil is not suppressed, good will not prosper”.27 And yet, for all the strength of feeling displayed in these statements there were many who argued against the enforcement of Tha 1- 12. Several representatives stressed that as a Buddhist... . As mentioned above, many felt that the thieves were “dupes” in a game in which they were the losers. Nor was it lost on my informants that the level of chorten and lhakhang robberies has risen since the late 1970s. Although not articulated, there was a strong...

  4. Deficiency of terminal complement pathway inhibitor promotes neuronal tau pathology and degeneration in mice

    E-Print Network [OSTI]

    Britschgi, Markus; Takeda-Uchimura, Yoshiko; Rockenstein, Edward; Johns, Hudson; Masliah, Eliezer; Wyss-Coray, Tony

    2012-01-01T23:59:59.000Z

    et al. : Deficiency of terminal complement pathway inhibitorAccess Deficiency of terminal complement pathway inhibitoran inhibitor of the terminal complement pathway. Complement

  5. Wick rotation for quantum field theories on degenerate Moyal space(-time)

    SciTech Connect (OSTI)

    Grosse, Harald; Lechner, Gandalf [Department of Physics, University of Vienna, 1090 Vienna (Austria)] [Department of Physics, University of Vienna, 1090 Vienna (Austria); Ludwig, Thomas [Max-Planck-Institute for Mathematics in the Sciences, 04103 Leipzig (Germany) [Max-Planck-Institute for Mathematics in the Sciences, 04103 Leipzig (Germany); Institute for Theoretical Physics, University of Leipzig, 04009 Leipzig (Germany); Verch, Rainer [Institute for Theoretical Physics, University of Leipzig, 04009 Leipzig (Germany)] [Institute for Theoretical Physics, University of Leipzig, 04009 Leipzig (Germany)

    2013-02-15T23:59:59.000Z

    In this paper the connection between quantum field theories on flat noncommutative space(-times) in Euclidean and Lorentzian signature is studied for the case that time is still commutative. By making use of the algebraic framework of quantum field theory and an analytic continuation of the symmetry groups which are compatible with the structure of Moyal space, a general correspondence between field theories on Euclidean space satisfying a time zero condition and quantum field theories on Moyal Minkowski space is presented ('Wick rotation'). It is then shown that field theories transferred to Moyal space(-time) by Rieffel deformation and warped convolution fit into this framework, and that the processes of Wick rotation and deformation commute.

  6. Level set simulations of turbulent thermonuclear deflagration in degenerate carbon and oxygen

    E-Print Network [OSTI]

    Schmidt, W; Niemeyer, J C

    2005-01-01T23:59:59.000Z

    We study the dynamics of thermonuclear flames propagating in fuel stirred by stochastic forcing. The fuel consists of carbon and oxygen in a state which is encountered in white dwarfs close to the Chandrasekhar limit. The level set method is applied to represent the flame fronts numerically. The computational domain for the numerical simulations is cubic, and periodic boundary conditions are imposed. The goal is the development of a suitable flame speed model for the small-scale dynamics of turbulent deflagration in thermonuclear supernovae. Because the burning process in a supernova explosion is transient and spatially inhomogeneous, the localised determination of subgrid scale closure parameters is essential. We formulate a semi-localised model based on the dynamical equation for the subgrid scale turbulence energy $k_{\\mathrm{sgs}}$. The turbulent flame speed $s_{\\mathrm{t}}$ is of the order $\\sqrt{2k_{\\mathrm{sgs}}}$. In particular, the subgrid scale model features a dynamic procedure for the calculation ...

  7. DIFFERENCE SCHEMES STABILIZED BY DISCRETE MOLLIFICATION FOR DEGENERATE PARABOLIC EQUATIONS IN TWO SPACE DIMENSIONS

    E-Print Network [OSTI]

    Bürger, Raimund

    : August 25, 2011. AUniversidad Nacional de Colombia, Department of Mathematics and Statistics, Manizales as entropy solutions. It is well known that certain monotone finite difference schemes converge, Colombia. E-Mail: cdacostam@unal.edu.co. BCI2MA and Departamento de Ingenier´ia Matem´atica, Facultad de

  8. DIFFERENCE SCHEMES STABILIZED BY DISCRETE MOLLIFICATION FOR DEGENERATE PARABOLIC EQUATIONS IN TWO SPACE DIMENSIONS

    E-Print Network [OSTI]

    Bürger, Raimund

    : October 18, 2011. AUniversidad Nacional de Colombia, Department of Mathematics and Statistics, Manizales as entropy solutions. It is well known that certain monotone finite difference schemes converge, Colombia. E-Mail: cdacostam@unal.edu.co. BCI2MA and Departamento de Ingenier´ia Matem´atica, Facultad de

  9. DIFFERENCE SCHEMES STABILIZED BY DISCRETE MOLLIFICATION FOR DEGENERATE PARABOLIC EQUATIONS IN TWO SPACE DIMENSIONS

    E-Print Network [OSTI]

    Bürger, Raimund

    Nacional de Colombia, Department of Mathematics and Statistics, Manizales, Colombia. E-Mail: cdacostam to be defined as entropy solutions. It is well known that certain monotone, and therefore first-order, finite

  10. NUMERICAL IDENTIFICATION OF PARAMETERS FOR STRONGLY DEGENERATE PARABOLIC EQUATIONS BY DISCRETE MOLLIFICATION

    E-Print Network [OSTI]

    Bürger, Raimund

    ]. Date: July 3, 2011. AUniversidad Nacional de Colombia, Department of Mathematics and Statistics. The direct problem is solved herein by a version of a well-known explicit, monotone three-point finite, Manizales, Colombia. E-Mail: cdacostam@unal.edu.co. BCI2MA and Departamento de Ingenier´ia Matem

  11. Impact of degenerate n-doping on the optical absorption edge in transparent conducting cadmium oxide

    E-Print Network [OSTI]

    Schleife, André

    n-type or can be heavily doped. Transparent conductive cadmium oxide (CdO) thin films, for instance devices or modern solar cells, material performance is critically important. A combination of high in the conduction bands of CdO can increase the conductivity up to values desired for technological applications

  12. On the structure of attractors for a class of degenerate reaction-diffusion systems

    E-Print Network [OSTI]

    Demaret, Laurent

    in [2], where the exis- tence of solutions and of global compact attractor has been shown. Furthermore of the solutions belonging to the global compact attractor. It is shown that for such solutions, the degeneracy

  13. Fluctuations and state preparation in quantum degenerate gases of sodium and lithium

    E-Print Network [OSTI]

    Su, Edward (Edward Joseph)

    2014-01-01T23:59:59.000Z

    Ultracold atoms enable the precise study of novel systems where the correlations between particles are strong. These systems can be simple to describe yet impossible to efficiently simulate on a classical computer; ...

  14. Antiferromagnetic Exchange Interaction between Electrons on Degenerate LUMOs in Benzene Dianion

    E-Print Network [OSTI]

    Matsuura, Hiroyasu; Fukuyama, Hidetoshi

    2012-01-01T23:59:59.000Z

    We discuss the ground state of Benzene dianion (Bz$^{2-}$) on the basis of the numerical diagonalization method of an effective model of $\\pi$ orbitals. It is found that the ground state can be the spin singlet state, and the exchange coupling between LUMOs can be antiferromagnetic.

  15. Noise-induced cochlear neuronal degeneration and its role in hyperacusis -- and tinnitus-like behavior

    E-Print Network [OSTI]

    Hickox, Ann E

    2013-01-01T23:59:59.000Z

    Perceptual abnormalities such as hyperacusis and tinnitus often occur following acoustic overexposure. Although such exposure can also result in permanent threshold elevation, some individuals with noise-induced hyperacusis ...

  16. Level set simulations of turbulent thermonuclear deflagration in degenerate carbon and oxygen

    E-Print Network [OSTI]

    W. Schmidt; W. Hillebrandt; J. C. Niemeyer

    2005-08-02T23:59:59.000Z

    We study the dynamics of thermonuclear flames propagating in fuel stirred by stochastic forcing. The fuel consists of carbon and oxygen in a state which is encountered in white dwarfs close to the Chandrasekhar limit. The level set method is applied to represent the flame fronts numerically. The computational domain for the numerical simulations is cubic, and periodic boundary conditions are imposed. The goal is the development of a suitable flame speed model for the small-scale dynamics of turbulent deflagration in thermonuclear supernovae. Because the burning process in a supernova explosion is transient and spatially inhomogeneous, the localised determination of subgrid scale closure parameters is essential. We formulate a semi-localised model based on the dynamical equation for the subgrid scale turbulence energy $k_{\\mathrm{sgs}}$. The turbulent flame speed $s_{\\mathrm{t}}$ is of the order $\\sqrt{2k_{\\mathrm{sgs}}}$. In particular, the subgrid scale model features a dynamic procedure for the calculation of the turbulent energy transfer from resolved toward subgrid scales, which has been successfully applied to combustion problems in engineering. The options of either including or suppressing inverse energy transfer in the turbulence production term are compared. In combination with the piece-wise parabolic method for the hydrodynamics, our results favour the latter option. Moreover, different choices for the constant of proportionality in the asymptotic flame speed relation, $s_{\\mathrm{t}}\\propto\\sqrt{2k_{\\mathrm{sgs}}}$, are investigated.

  17. Non-degenerate pump-probe spectroscopy of single GaN nanowires

    SciTech Connect (OSTI)

    Upadhya, Prashanth C [Los Alamos National Laboratory; Taylor, Antoinette J [Los Alamos National Laboratory; Prasankumar, Rohiy P [Los Alamos National Laboratory; Wang, George T [SNL; Martinez, Julio A [SNL; Li, Qiming [SNL; Swartzentruber, Brian S [SNL

    2010-01-01T23:59:59.000Z

    Spatially-resolved ultrafast transient absorption measurements on a single GaN nanowire give insight into carrier relaxation dynamics as a function of the probe polarization and position on the nanowire on a femtosecond timescale. The synthesis and optical characterization of semiconductor nanowires (NWs) has gained considerable attention in recent years owing to their unique electronic and optical properties that arise from their anisotropic geometry, large surface to volume ratio and two-dimensional quasiparticle confinement, Post-growth characterization of their properties is crucial in understanding the fundamental physical processes that can lead to enhanced functionality of NW-based devices, In particular, it is important to understand the carrier relaxation pathways in individual NWs, since the geometry of these nanostructures can significantly influence carrier recombination and/or trapping. In this respect, ultrafast optical techniques offer reliable and non-contact spectroscopic tools to study carrier dynamics in semiconductor nanostructures. In summary, time-resolved optical pump-probe spectroscopy was performed on single GaN NWs. These measurements give insight into the different processes that govern carrier capture, particularly at surface states, and relaxation in individual nanostructures. Our experiments thus demonstrate the value of single-particle ultrafast optical spectroscopy in understanding the physical processes that govern the properties of semiconductor NWs, while suggesting approaches to optimize NW-based devices for nanophotonic applications.

  18. Integrability and Boundedness of Local Solutions to Singular and Degenerate Quasilinear Parabolic

    E-Print Network [OSTI]

    O'Leary, Michael

    Equations Mike O'Leary Abstract Integral and supremum estimates are proven for local solutions of de- 1 ) + c5|u|-1 + 2(x, t), AMS Classifications: 35K65, 35B45 Mike O'Leary, Department of Mathematics, Towson University, Towson, MD 21252 moleary@towson.edu #12;2 M. O'Leary (H5) 1 L p p-1 ,loc(T ), (H6) o

  19. Degenerate Ising model for atomistic simulation of crystal-melt interfaces

    SciTech Connect (OSTI)

    Schebarchov, D., E-mail: Dmitri.Schebarchov@gmail.com [University Chemical Laboratories, Lensfield Road, Cambridge CB2 1EW (United Kingdom); Schulze, T. P., E-mail: schulze@math.utk.edu [Department of Mathematics, University of Tennessee, Knoxville, Tennessee 37996-1300 (United States); Hendy, S. C. [The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington 6140 (New Zealand) [The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, Wellington 6140 (New Zealand); Department of Physics, University of Auckland, Auckland 1010 (New Zealand)

    2014-02-21T23:59:59.000Z

    One of the simplest microscopic models for a thermally driven first-order phase transition is an Ising-type lattice system with nearest-neighbour interactions, an external field, and a degeneracy parameter. The underlying lattice and the interaction coupling constant control the anisotropic energy of the phase boundary, the field strength represents the bulk latent heat, and the degeneracy quantifies the difference in communal entropy between the two phases. We simulate the (stochastic) evolution of this minimal model by applying rejection-free canonical and microcanonical Monte Carlo algorithms, and we obtain caloric curves and heat capacity plots for square (2D) and face-centred cubic (3D) lattices with periodic boundary conditions. Since the model admits precise adjustment of bulk latent heat and communal entropy, neither of which affect the interface properties, we are able to tune the crystal nucleation barriers at a fixed degree of undercooling and verify a dimension-dependent scaling expected from classical nucleation theory. We also analyse the equilibrium crystal-melt coexistence in the microcanonical ensemble, where we detect negative heat capacities and find that this phenomenon is more pronounced when the interface is the dominant contributor to the total entropy. The negative branch of the heat capacity appears smooth only when the equilibrium interface-area-to-volume ratio is not constant but varies smoothly with the excitation energy. Finally, we simulate microcanonical crystal nucleation and subsequent relaxation to an equilibrium Wulff shape, demonstrating the model's utility in tracking crystal-melt interfaces at the atomistic level.

  20. Malliavin calculus for highly degenerate 2D stochastic Navier-Stokes equations

    E-Print Network [OSTI]

    Hairer, Martin

    , UK bMath Department, Duke University, Box 90320, Durham, NC 27708 USA cLATP/CMI, Universit´e de Hairer), jonm@math.duke.edu (Jonathan C. Mattingly), pardoux@cmi.univ-mrs.fr (´Etienne Pardoux). Preprint submitted to Elsevier Science August 2004 #12;1. Introduction This note reports on recent progress made

  1. J. Am. Chem. SOC.1991, 113, 3451-3458 3451 Degenerate Transesterification of

    E-Print Network [OSTI]

    Smith, Bradley D.

    aggregatespecies: THF tetramer, 6.5;DME tetramer, 3.3 (40 "C);dioxolane, 13, hexamer, 71; pyridine tetramer, 2. These results are interpreted in terms of a preequilibrium in which a solventon lithium in the tetramer

  2. Adaptive optics microperimetry and OCT images show preserved function and recovery of cone visibility in macular telangiectasia type 2 retinal lesions

    E-Print Network [OSTI]

    2015-01-01T23:59:59.000Z

    imaging through adaptive optics. J Opt Soc Am A Opt Imageusing a confocal adaptive optics scanning ophthalmoscope.T, Campbell M. Adaptive optics scanning laser ophthalmosco-

  3. Diamond and Related Materials, 2 (1993) 661 666 661 Degenerate four-wave mixing diagnostics of atmospheric pressure

    E-Print Network [OSTI]

    Zare, Richard N.

    -3]. An r.f. inductively coupled plasma offers the benefits of an "electrodeless" discharge for minimum film application of this new spectroscopic technique to an atmospheric pressure plasma synthesis reactor. DFWM measurements of the CH radicals in the boundary layer of an r.f. inductively coupled plasma deposition reactor

  4. CHIN.PHYS.LETT. Vol. 25, No. 3 (2008) 843 Quantum Degenerate FermiBose Mixtures of 40

    E-Print Network [OSTI]

    Zhang, Jing

    No 2006CB921101, the National Natural Science Foundation of China for Distinguished Young Scholars under Grant No 10725416, the National Natural Science Foundation of China under Grant No 60678029 gas 40 K by evaporatively cooling bosonic 87 Rb atoms in a quadrupole-Ioffe configura- tion (QUIC

  5. Production of bosonic molecules in the nonequilibrium dynamics of a degenerate Fermi gas across a Feshbach resonance 

    E-Print Network [OSTI]

    Dobrescu, Bogdan E.

    2009-06-02T23:59:59.000Z

    . The approach is based on evaluating real-time Green functions within the Keldysh- Schwinger formalism. The effects of quantum statistics associated with Pauli blocking for fermions and induced emission for bosons, characteristic of particle scattering in a...

  6. Performance of photovoltaic arrays in-vivo and characteristics of prosthetic vision in animals with retinal degeneration

    E-Print Network [OSTI]

    Palanker, Daniel

    Performance of photovoltaic arrays in-vivo and characteristics of prosthetic vision in animals neurons. Subretinal photovoltaic arrays convert pulsed illumination into pulsed electric current produced by each pixel, and thereby assessing the changes in the implant performance over time. Ó 2014

  7. Optimizing the utility of diffusion imaging for discovering genetic and environmental influences on neural development, degeneration, and disease

    E-Print Network [OSTI]

    Jahanshad, Neda

    2012-01-01T23:59:59.000Z

    handedness, gender and dyslexia: a review of the evidence.handedness, gender, and dyslexia: a review of the evidence.in groups of patients with dyslexia (Beaton, 1997), Williams

  8. Highest-energy cosmic rays from Fermi-degenerate relic neutrinos consistent with Super-Kamiokande results

    E-Print Network [OSTI]

    Graciela Gelmini; Alexander Kusenko

    1999-05-17T23:59:59.000Z

    Relic neutrinos with mass 0.07 (+0.02/-0.04) eV, in the range consistent with Super-Kamiokande data, can explain the cosmic rays with energies in excess of the Greisen-Zatsepin-Kuzmin cutoff. The spectrum of ultra-high energy cosmic rays produced in this fashion has some distinctive features that may help identify their origin. Our mechanism does not require but is consistent with a neutrino density high enough to be a new kind of hot dark matter.

  9. Optimizing the utility of diffusion imaging for discovering genetic and environmental influences on neural development, degeneration, and disease

    E-Print Network [OSTI]

    Jahanshad, Neda

    2012-01-01T23:59:59.000Z

    C. A. , Auinger, P. , & Szilagyi, P. G. 2001. Iron de?ciencyJM, Aligne CA, Auinger P, Szilagyi PG (2001) Iron de?ciencyJM, Aligne CA, Auinger P, Szilagyi PG. Iron de?ciency and

  10. ccsd-00083161,version2-11Sep2006 MIXING ANGLES AND NON-DEGENERATE COUPLED SYSTEMS OF PARTICLES

    E-Print Network [OSTI]

    Boyer, Edmond

    to the Higgs boson are not flavor-diagonal, massive fermions in the standard model form coupled systems (like

  11. Optimizing power to track brain degeneration in Alzheimer's disease and mild cognitive impairment with tensor-based morphometry

    E-Print Network [OSTI]

    Thompson, Paul

    . Leow a,b , Yi-Yu Chou a , April J. Ho a , Boris Gutman a , Arthur W. Toga a , Clifford R. Jack Jr d,j , Gene E. Alexander l , Michael W. Weiner i,j,k,l , Paul M. Thompson a, and the Alzheimer's Disease

  12. A Flexible Source of Non-Degenerate Entangled Photons Based on a Two-Crystal Sagnac Interferometer

    E-Print Network [OSTI]

    Terence E. Stuart; Joshua A. Slater; Felix Bussieres; Wolfgang Tittel

    2013-05-05T23:59:59.000Z

    Sources of entangled photon pairs are a key component in both fundamental tests of quantum theory and practical applications such as quantum key distribution and quantum computing. In this work, we describe and characterize a source of polarization entangled photon pairs based on two spontaneous parametric down-conversion (SPDC) crystals in a Sagnac interferometer. Our source is compact and produces high-quality entangled states in a very flexible manner. The wavelengths of the photon pairs, around 810 and 1550 nm, the phase between orthogonal components of the entangled state, and the tangle of the state are all independently adjustable. In addition to presenting basic characterization data, we present experimental violations of CHSH and Leggett inequalities, as well as an instance of the "beautiful" Bell inequality, which has not previously been tested experimentally.

  13. Reprintedfrom American Journal of Ophthalmology

    E-Print Network [OSTI]

    Boppart, Stephen

    . ROACH, PHD optical coherence tomography images 0£ macular laser lesions clearly demonstrated differences, Boiling AFB, District of Columbia (Dr Roach). This researchwassponsored by USAF Armstrong Laboratory

  14. Effect of autologous platelet-rich plasma-releasate on intervertebral disc degeneration in the rabbit anular puncture model: a preclinical study

    E-Print Network [OSTI]

    2012-01-01T23:59:59.000Z

    discs. Autologous PRP and PPP (platelet-poor plasma) werethe initial puncture, releasate isolated from clotted PPP orPRP (PPP- or PRP-releasate), or phosphate-buffered saline (

  15. Top-Quark Mass Data and the Sum of Quasi-Degenerate Neutrino Masses (One small electroweak-bound e-parameter organizes elementary particle 3-flavor phenomenology)

    E-Print Network [OSTI]

    E. M. Lipmanov

    2008-10-01T23:59:59.000Z

    The absolute neutrino masses and type of neutrino mass hierarchy are among the main problems in neutrino physics. Top-quark mass is another topical problem in particle physics. These problems extend the old puzzle of electron-muon mass ratio close to the fine structure constant, which is still not solved by known theory. Here I continue the search for a general flavor pattern that may incorporate these problems. Relations between neutrino/electron and electron/top-quark pole mass ratios are obtained from supposition that realistic elementary particle dimensionless bare flavor quantities are small deviated (measured by universal parameter e) from the values of a stated flavor pattern (at e=0) and experimental data hints. With the world average t-quark mass data the sum of QD-neutrino masses is estimated (0.50 +- 0.003)eV in agreement with cosmological constraints and known QD-neutrino mass estimations from experimental data on neutrino oscillation mass-squared differences.

  16. Fusion Rules of the Lowest Weight Representations of osp_q(1|2) at Roots of Unity: Polynomial Realization and Degeneration at Roots of Unity

    E-Print Network [OSTI]

    D. Karakhanyan; Sh. Khachatryan

    2009-08-27T23:59:59.000Z

    The degeneracy of the lowest weight representations of the quantum superalgebra $osp_q(1|2)$ and their tensor products at exceptional values of %when deformation parameter $q$ takes exceptional values is studied. The main features of the structures of the finite dimensional lowest weight representations and their fusion rules are illustrated using realization of group generators as finite-difference operators acting in the space of the polynomials. The complete fusion rules for the decompositions of the tensor products at roots of unity are presented. The appearance of indecomposable representations in the fusions is described using Clebsh-Gordan coefficients derived for general values of $q$ and at roots of unity.

  17. station ALOHA, samples were amplified by polymerase chain reaction (PCR) with a nested set of degenerate nifH primers19,20

    E-Print Network [OSTI]

    Jackson, David

    production and photosynthetic rates within and outside a cyclonic mesoscale eddy in the North Pacific

  18. The JET Alfvn Eigenmode Local Manager for the real-time detection and tracking of a frequency-degenerate spectrum of MHD instabilities

    E-Print Network [OSTI]

    Lenstra, Arjen K.

    1 The JET Alfvén Eigenmode Local Manager for the real-time detection and tracking of a frequency,5 , A.Klein6 , P.Lavanchy1 , T.Panis1 , and JET-EFDA contributors JET-EFDA, Culham Science Centre, OX14, FR [3] Culham Centre for Fusion Energy, Culham Science Centre, Abingdon, UK [4] formerly: JET Joint

  19. The Vacuolar-ATPase Complex Regulates Retinoblast Proliferation and Survival, Photoreceptor

    E-Print Network [OSTI]

    Gross, Jeff

    morphogenesis (e.g., Refs. 2­4). In adults, RPE cells play a central role in the transport of ions, water. Several blinding diseases in humans, such as Leber's congenital amaurosis,5,6 Best macular dystrophy,7

  20. www.sciencemag.org SCIENCE VOL 300 2 MAY 2003 703 D E V E L O P M E N T

    E-Print Network [OSTI]

    Gates, Kent. S.

    on testicular devel- opment, degeneration, and infertility. -- LDC Development 130, 1029 (2003); Nature Genet

  1. VOLUME 88, NUMBER 16 P H Y S I C A L R E V I E W L E T T E R S 22 APRIL 2002 Two-Species Mixture of Quantum Degenerate Bose and Fermi Gases

    E-Print Network [OSTI]

    cooling of fermionic 6 Li in a thermal bath of bosonic 23 Na. The system features rapid thermalization, for sympathetic cooling of 6 Li. Our work provides the natural progression in t; published 4 April 2002) We have produced a macroscopic quantum system in which a 6 Li Fermi sea coexists

  2. Search for charginos nearly mass degenerate with the lightest neutralino based on a disappearing-track signature in pp collisions at ?s = 8 TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search is presented for direct chargino production based on a disappearing-track signature using 20.3??fb[superscript ?1] of proton-proton collisions at s? = 8??TeV collected with the ATLAS experiment at the LHC. In ...

  3. Stockpile Stewardship Quarterly

    National Nuclear Security Administration (NNSA)

    result in component performance degradation, including aging of electrical contacts, corrosion, fatigue, hermeticity, and age-related degradation of seals, coatings, and...

  4. Insulin signaling, dietary restriction and DNA damage : multiple roles for smk-1 in the mediation of C. elegans life span

    E-Print Network [OSTI]

    Wolff, Suzanne Christine

    2008-01-01T23:59:59.000Z

    role of oxidative damage and environmental stresses. Natureand environmental insults drive the accumulation of DNA damageenvironmental state. While age- related decay still occurs (due to oxidative damage and

  5. 8.06 Quantum Physics III, Spring 2003

    E-Print Network [OSTI]

    Rajagopal, Krishna, 1965-

    Continuation of 8.05. Units: natural units, scales of microscopic phenomena, applications. Time-independent approximation methods: degenerate and non-degenerate perturbation theory, variational method, Born-Oppenheimer ...

  6. Mechanical injury and inflammatory cytokines affect cartilage integrity and tissue homeostasis : a mass spectrometric analysis of proteins with relevance to arthritis

    E-Print Network [OSTI]

    Stevens, Anna L. (Anna Lea)

    2006-01-01T23:59:59.000Z

    Osteoarthritis is characterized by synovial joint degeneration, and its cardinal pathological feature is degeneration and loss of the articular cartilage joint surface. While the aetiology of osteoarthritis is unknown, ...

  7. MATHEMATICAL AND NUMERICAL ANALYSIS OF A TRANSIENT EDDY CURRENT PROBLEM ARISING FROM

    E-Print Network [OSTI]

    Rodríguez, Rodolfo

    MATHEMATICAL AND NUMERICAL ANALYSIS OF A TRANSIENT EDDY CURRENT PROBLEM ARISING FROM transient axisymmetric eddy current problem governing such phenomenon. The resulting problem is degenerate. Electromagnetic forming, finite elements, eddy current, transient electromagnetics, degenerate parabolic problems

  8. Just over 3,000 years ago at the time of the Yellow Emperor, the Chinese were the first

    E-Print Network [OSTI]

    Olufsen, Mette Sofie

    . His lungs begin to degenerate, he has cough in the winter time, but by his pulse you will know him

  9. Wednesday, August 21, 2013 Biological Sciences Learning Center | Room 115

    E-Print Network [OSTI]

    Issa, Naoum

    the Correlation Mentor: Jacqueline Bernard, MD 9:20am Gabrielle Liu Retinal Nerve Fiber Layer and Macular Thinning Guided L5/S1 Placement of Labor Epidurals Does Not Improve Dermatomal Blockade in Parturients Mentor in Myelofibrosis Mentor: Olatoyosi Odenike, MD 11:30am Michael Ramirez Automated Segmentation of Sinus Mucosa

  10. Wavelength-doubling optical parametric oscillator

    DOE Patents [OSTI]

    Armstrong, Darrell J. (Albuquerque, NM); Smith, Arlee V. (Albuquerque, NM)

    2007-07-24T23:59:59.000Z

    A wavelength-doubling optical parametric oscillator (OPO) comprising a type II nonlinear optical medium for generating a pair of degenerate waves at twice a pump wavelength and a plurality of mirrors for rotating the polarization of one wave by 90 degrees to produce a wavelength-doubled beam with an increased output energy by coupling both of the degenerate waves out of the OPO cavity through the same output coupler following polarization rotation of one of the degenerate waves.

  11. E-Print Network 3.0 - amaurosis protein aipl1 Sample Search Results

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

    chaperones, RP2 and AIPL1. Molecular chaperone mediated protein... and protein folding in human disease, particularly retinal degeneration and neurodegeneration. We...

  12. aqueous ionic liquids: Topics by E-print Network

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

    The resulting dynamical equations can be written as a gradient flow with a degenerate mobility function. This form of the mobility function gives rise to charging behaviours that...

  13. On the Uniqueness of the Papapetrou--Majumdar Metric

    E-Print Network [OSTI]

    M. Heusler

    1996-07-01T23:59:59.000Z

    We establish the equality of the ADM mass and the total electric charge for asymptotically flat, static electrovac black hole spacetimes with completely degenerate, not necessarily connected horizon.

  14. Decentralizing urbanization : harnessing the potential of small cities in India

    E-Print Network [OSTI]

    Suri, Sagarika

    2011-01-01T23:59:59.000Z

    Perceived as symbols of national development or degeneration, megacities continue to dominate discourse and action related to urbanization, particularly in developing countries like India. Simultaneously, a large portion ...

  15. acids modulate glucocorticoid: Topics by E-print Network

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

    purposes, ulcerated monkeys had marked hippocampal degeneration Hideo Uno; Ross Tarara; James G. Else; Mbaruk A. Suleman; Robert M. Sapolsky 1990-01-01 33 Transcriptional...

  16. atypical thermonuclear supernovae: Topics by E-print Network

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

    Websites Summary: White dwarf mergers,White dwarf mergers, thermonuclear supernovae,thermonuclear supernovae fusion is ignited. Degenerate, hence runaway. 12;CO white dwarf...

  17. The Impact of Biomechanics in Tissue Engineering and Regenerative Medicine

    E-Print Network [OSTI]

    Butler, David L.

    Biomechanical factors profoundly influence the processes of tissue growth, development, maintenance, degeneration, and repair. Regenerative strategies to restore damaged or diseased tissues in vivo and create living tissue ...

  18. SirT1 regulates bone mass in vivo through regulation of osteoblast and osteoclast differentiation

    E-Print Network [OSTI]

    Zainabadi, Kayvan

    2009-01-01T23:59:59.000Z

    As mammals age, osteoblast numbers decrease while osteoclast numbers increase, resulting in age-related or post-menopausal osteoporosis. SirT1, the mammalian orthologue of yeast Sir2, has been shown to be a negative regulator ...

  19. Institute for Critical Technology and Applied Science

    E-Print Network [OSTI]

    Crawford, T. Daniel

    . General & Age Related Disabilities Engineering Program (GARDE), 2. CBET-National Robotics Initiative (NRIProfessorinMechanical,MaterialsandAerospaceEngineeringattheUniversityofCentralFlorida(UCF) in Orlando, FL. Before arriving at UCF, he accepted the tenure-track position of Assistant Professor

  20. Effect of hypertension on the structural and functional integrity of the young and aged brain in an inducible transgenic model 

    E-Print Network [OSTI]

    Pannozzo, Mercede Alcina

    2014-06-28T23:59:59.000Z

    Hypertension has been associated with causing deleterious effects to the cerebrovasculature, which are thought to underlie the formation of white matter lesions (WML) and predispose individuals to age related cognitive ...

  1. The characterization of human [gamma]D-crystallin mutants and their differential interactions with the lens chaperone [alpha]B-crystallin

    E-Print Network [OSTI]

    Moreau, Kate L. (Kate Lauren)

    2011-01-01T23:59:59.000Z

    Cataract, the leading cause of blindness worldwide, is the opacification of the eye lens. In.age-related cataract, as well as roughly one half of congenital cataract cases, aggregation or precipitation of crystallin proteins ...

  2. Aging considerations for PWR (pressurized water reactor) control rod drive mechanisms and reactor internals

    SciTech Connect (OSTI)

    Ware, A.G.

    1988-01-01T23:59:59.000Z

    This paper describes age-related degradation mechanisms affecting life extension of pressurized water reactor control rod drive mechanisms and reactor internals. The major sources of age-related degradation for control rod drive mechanisms are thermal transients such as plant heatups and cooldowns, latchings and unlatchings, long-term aging effects on electrical insulation, and the high temperature corrosive environment. Flow induced loads, the high-temperature corrosive environment, radiation exposure, and high tensile stresses in bolts all contribute to aging related degradation of reactor internals. Another problem has been wear and fretting of instrument guide tubes. The paper also discusses age-related failures that have occurred to date in pressurized water reactors.

  3. Normal Aging and the Dissociable Prototype Learning Systems Brian D. Glass

    E-Print Network [OSTI]

    Chittka, Lars

    learning (Ashby & Mad- dox, 2005). Recent research suggests there is an age-related deficit in rule, Pacheco, Reeves, Zhu, & Schnyer, 2010, and see Filoteo & Mad- dox, 2004). Another important type

  4. Does Age Effect Dual-tasking Ability? Data from Healthy Participants using a new Experimental Paradigm. 

    E-Print Network [OSTI]

    Ghazali, Zayba

    2011-06-29T23:59:59.000Z

    OBJECTIVES: This study aimed to explore age-related differences in dual-tasking. Previous studies report no age-effects in dual-tasking among healthy individuals in comparison to severe dual-tasking impairment in Alzheimer’s ...

  5. Exercise training modulates apoptotic signaling in the aging rat heart

    E-Print Network [OSTI]

    Kwak, Hyo Bum

    2005-11-01T23:59:59.000Z

    Aging is characterized by a progressive decline in cardiac function. A critical contributor to the age-related impairment in heart function is the loss of cardiac myocytes through ??apoptosis??, or programmed cell death. A dramatic increase...

  6. Genetic Regulation of Caenorhabditis elegans Lysosome Related Organelle Function

    E-Print Network [OSTI]

    Soukas, Alexander A.

    Lysosomes are membrane-bound organelles that contain acid hydrolases that degrade cellular proteins, lipids, nucleic acids, and oligosaccharides, and are important for cellular maintenance and protection against age-related ...

  7. Behavioral impulsivity and hallucinations : insights from Parkinson's disease

    E-Print Network [OSTI]

    Ashourian, Paymon

    2011-01-01T23:59:59.000Z

    Parkinson's disease (PD) is an age-related degenerative disease of the brain, characterized by motor, cognitive, and psychiatric symptoms. Neurologists and neuroscientists now understand that several symptoms of the disease, ...

  8. Establishing a rodent (Fischer 344 rat) model of mild cognitive impairment in aging

    E-Print Network [OSTI]

    LaSarge, Candi Lynn

    2009-05-15T23:59:59.000Z

    characterized on the reference memory version of the water maze were tested on either a spatial working memory water maze task or an olfactory discrimination task. Despite detecting an age-related delay-dependent decline in spatial working memory...

  9. Transforming growth factor alpha (TGFAlpha) in testicular development of the prepubertal boar

    E-Print Network [OSTI]

    Gillespie, Joe Curtis

    1993-01-01T23:59:59.000Z

    used to characterize age-related changes in cell distribution and density of TGFA. The aspects of the proliferation of Leydig and Sertoli ceus and the presence of TGFA were determined by the inimunocytochemical and the morphometric analyses...

  10. Tryptophan Cluster Protects Human ?D-Crystallin from Ultraviolet Radiation-Induced Photoaggregation

    E-Print Network [OSTI]

    Schafheimer, Steven Nathaniel

    Exposure to ultraviolet radiation (UVR) is a significant risk factor for age-related cataract, a disease of the human lens and the most prevalent cause of blindness in the world. Cataract pathology involves protein misfolding ...

  11. Tyrosine/Cysteine Cluster Sensitizing Human ?D-Crystallin to Ultraviolet Radiation-Induced Photoaggregation in Vitro

    E-Print Network [OSTI]

    Schafheimer, Steven Nathaniel

    Ultraviolet radiation (UVR) exposure is a major risk factor for age-related cataract, a protein-aggregation disease of the human lens often involving the major proteins of the lens, the crystallins. ?D-Crystallin (H?D-Crys) ...

  12. Risk factors for cognitive decline in older people with type 2 diabetes 

    E-Print Network [OSTI]

    Feinkohl, Insa

    2014-07-05T23:59:59.000Z

    People with type 2 diabetes are at increased risk of age-related cognitive impairment. Previous literature has focused on case-control studies comparing rates of cognitive impairment in patients with and without diabetes. ...

  13. Retinal microvascular abnormalities and cognitive function in older people with type 2 diabetes 

    E-Print Network [OSTI]

    Ding, Jie

    2010-11-24T23:59:59.000Z

    The deleterious effects of Type 2 diabetes on the brain have been shown to result in a greater prevalence of age-associated cognitive impairment and an enhanced risk of age-related cognitive decline in older diabetic ...

  14. Accepted Manuscript Comment on "Ccl2, Cx3cr1 and Ccl2/Cx3cr1 chemokine deficiencies are not sufficient

    E-Print Network [OSTI]

    Boyer, Edmond

    Accepted Manuscript Comment on "Ccl2, Cx3cr1 and Ccl2/Cx3cr1 chemokine deficiencies on "Ccl2, Cx3cr1 and Ccl2/Cx3cr1 chemokine deficiencies are not sufficient to cause age- related retinal on "Ccl2, Cx3cr1 and Ccl2/Cx3cr1 chemokine deficiencies are not sufficient to cause age- related retinal

  15. White dwarf mergers,White dwarf mergers, thermonuclear supernovae,thermonuclear supernovae,

    E-Print Network [OSTI]

    Hinton, Jim

    White dwarf mergers,White dwarf mergers, thermonuclear supernovae,thermonuclear supernovae fusion is ignited. Degenerate, hence runaway. #12;CO white dwarf accretes, either from companion, or from disk after merger. As it approaches maximum mass, C fusion is ignited. Degenerate, hence runaway. SN Ia

  16. FiltrationinPorousMediaandIndustrialApplications(Cetraro,Italy1998),9-77,LectureNotesinMath.,1734,Springer,Berlin,2000 NUMERICAL SOLUTION OF RESERVOIR FLOW MODELS BASED ON

    E-Print Network [OSTI]

    Karlsen, Kenneth Hvistendahl

    , 137] have been constructed to describe the complex dynamics of reser- voir flow processes. A black-oil for the saturation equation, which is a convection dominated, degenerate convection-diffusion equation. Both theory for quasilinear degenerate parabolic equations, which provides the correct mathematical framework in which

  17. On the Zariski closure of a germ of totally geodesic complex submanifold on a subvariety of a

    E-Print Network [OSTI]

    Mok, Ngaiming

    geometry is the Gauss map. Ein [Ei, 1982] proved that the Gauss map of a linearly non-degenerate projective-geometric terms, generic finiteness of the Gauss map on a lin- early non-degenerate projective submanifold W Pn. The projective second fundamental form is on the one hand by definition determined by the canonical projective

  18. On a HeleShaw type domain evolution with convected surface energy density

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    generalizes surface­tension driven Hele­Shaw flow to the case of non­ constant surface tension coe#cient taken the surface tension coe#cient degenerates. The problem is reformulated as a vector­valued, degenerate variations of the surface energy density (corresponding to the surface tension coe#cient #) on surface

  19. Quantum versus classical descriptions of sub-Poissonian light generation in three-wave mixing

    E-Print Network [OSTI]

    Jiri Bajer; Adam Miranowicz

    2001-07-20T23:59:59.000Z

    Sub-Poissonian light generation in the non-degenerate three-wave mixing is studied numerically and analytically within quantum and classical approaches. Husimi Q-functions and their classical trajectory simulations are analysed to reveal a special regime corresponding to the time-stable sub-Poissonian photocount statistics of the sum-frequency mode. Conditions for observation of this regime are discussed. Theoretical predictions of the Fano factor and explanation of the extraordinary stabilization of the sub-Poissonian photocount behavior are obtained analytically by applying the classical trajectories. Scaling laws for the maximum sub-Poissonian behavior are found. Noise suppression levels in the non-degenerate vs degenerate three-wave mixing are discussed on different time scales compared to the revival times. It is shown that the non-degenerate conversion offers much better stabilization of the suppressed noise in comparison to that of degenerate process.

  20. Plasmon decay to a neutrino pair via neutrino electromagnetic moments in a strongly magnetized medium

    E-Print Network [OSTI]

    A. V. Borisov; P. E. Sizin

    2014-06-12T23:59:59.000Z

    We calculate the neutrino luminosity of a degenerate electron gas in a strong magnetic field via plasmon decay to a neutrino pair due to neutrino electromagnetic moments and obtain the relative upper bounds on the effective neutrino magnetic moment.

  1. A MOLECULAR ANALYSIS OF PROTEIN TRAFFICKING IN THE VERTEBRATE RETINA: IMPLICATIONS FOR INTRAFLAGELLAR TRANSPORT AND DISEASE

    E-Print Network [OSTI]

    Krock, Bryan L.

    2010-07-14T23:59:59.000Z

    trafficking. However, it was unclear whether photoreceptor degeneration in this disease is cell-autonomous, due to defective opsin transport within the photoreceptor, or is noncell-autonomous and a secondary consequence of defective RPE. Utilizing...

  2. A collagen based scaffold for the repair of annulus fibrosus defects

    E-Print Network [OSTI]

    Saad, Leonide C. (Leonide Camile), 1977-

    2007-01-01T23:59:59.000Z

    The intervertebral disc (IVD) is the natural cartilaginous cushion found between the osseous vertebrae of the spinal column. It is an essential element for the flexibility of the spine but undergoes major degeneration with ...

  3. A collagen-GAG matrix for the growth of intervertebral disc tissue

    E-Print Network [OSTI]

    Hastreiter, Dawn (Dawn Marie), 1973-

    2002-01-01T23:59:59.000Z

    Intervertebral disc (IVD) degeneration and herniation is a significant problem, more so in the aviation field. The IVD also changes during spaceflight. Current treatments for IVD problems can have unfavorable long-term ...

  4. autotrophic hollow-fiber membrane-aerated: Topics by E-print...

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

    Engineering Websites Summary: optical modulation in a degenerate V-system with a tapered nano fiber in atomic vapor," Opt. Express 19-optical switching using slow light within a...

  5. Two-dimensional ultrafast pulse shaping and its application to coherent control and spectroscopy

    E-Print Network [OSTI]

    Vaughan, Joshua Charles

    2005-01-01T23:59:59.000Z

    This thesis develops powerful new methods for shaping femtosecond laser pulses in two dimensions and explores their application to coherent control of propagating lattice excitations and degenerate four-wave mixing ...

  6. From Nonlinear PDEs to Singular ODEs University of Bath, Department of Mathematical Sciences, Bath, BA 27 AY, UK

    E-Print Network [OSTI]

    Burton, Geoffrey R.

    ) which is a model for the temperature profile of a fusion reactor plasma with one source term [15]. We that the equation (1) degenerates at the boundary if > 0. This does not affect the calculation of blow-up however

  7. From Nonlinear PDEs to Singular ODEs University of Bath, Department of Mathematical Sciences, Bath, BA 27 AY, UK

    E-Print Network [OSTI]

    Weinmüller, Ewa B.

    ) which is a model for the temperature profile of a fusion reactor plasma with one source term [15]. We]. Note that the equation (1) is degenerated at the boundary if > 0. This does not affect the calculation

  8. A TRANSIENT EDDY CURRENT PROBLEM ON A MOVING DOMAIN. MATHEMATICAL ANALYSIS

    E-Print Network [OSTI]

    Rodríguez, Rodolfo

    A TRANSIENT EDDY CURRENT PROBLEM ON A MOVING DOMAIN. MATHEMATICAL ANALYSIS ALFREDO BERM is to introduce and analyze a weak formulation of the transient eddy current problem governing electromagnetic. Electromagnetic forming, transient eddy current problem, axisymmetric problem, degenerate parabolic problem

  9. High-Performance Single Layered WSe2 p-FETs with Chemically Doped Contacts

    E-Print Network [OSTI]

    California at Irvine, University of

    by using high work function Pd contacts along with degenerate surface doping of the contacts by patterned by the gate electrode.3 For sub-5 nm gate lengths, this corresponds to channel materials with only 1-2 atomic

  10. acoustic electron spin resonance: Topics by E-print Network

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

    of electrons with spin-up and electrons with spin-down. In terms of new model we consider propagation of waves in magnetized plasmas of degenerate electrons and motionless ions. We...

  11. Bone Marrow Stimulation of the Medial Femoral Condyle Produces Inferior Cartilage and Bone Repair Compared to the Trochlea in a

    E-Print Network [OSTI]

    Buschmann, Michael

    Bone Marrow Stimulation of the Medial Femoral Condyle Produces Inferior Cartilage and Bone Repair femoral condylar (MFC) versus femoral trochlear (TR) defects 3 months after bone marrow stimulation: cartilage repair; medial femoral condyle; trochlea; bone marrow stimulation; meniscus degeneration Articular

  12. Experiments with interacting Bose and Fermi gases

    E-Print Network [OSTI]

    Stan, Claudiu Andrei

    2005-01-01T23:59:59.000Z

    In the past few years, the study of trapped fermionic atoms evolved from the first cooling experiments which produced quantum degenerate samples to becoming one of the most exciting branches of current atomic physics ...

  13. Uniaxial strain in graphene by Raman spectroscopy: G peak splitting, Grüneisen parameters, and sample orientation

    E-Print Network [OSTI]

    Mohiuddin, T. M. G.

    We uncover the constitutive relation of graphene and probe the physics of its optical phonons by studying its Raman spectrum as a function of uniaxial strain. We find that the doubly degenerate E[subscript 2g] optical mode ...

  14. In-vivo cartilage contact biomechanics : an experimental and computational investigation of human ankle joint complex

    E-Print Network [OSTI]

    Wan, Lu, Ph. D. Massachusetts Institute of Technology

    2008-01-01T23:59:59.000Z

    Osteoarthritis is affecting over 20 million people in the United States, the etiology of which is still unclear. As abnormal stress is believed to be one of the factors causing the degeneration of cartilage, the combined ...

  15. Is the central binary system of the planetary nebula Henize 2-428 a Type Ia supernova progenitor?

    E-Print Network [OSTI]

    Garcia-Berro, Enrique; Althaus, Leandro G

    2015-01-01T23:59:59.000Z

    We account for recent observations of the binary system at the center of the bipolar planetary nebula Henize 2-428 by the presence of one degenerate core with a low-mass main sequence companion, rather than by two degenerate objects. We argue that the variability of the He II 5412A spectral line can be accounted for by a time-varying broad absorption line from the central star on top of which there is a time-varying narrow emission line from the compact nebula. The two (almost) symmetric broad minima in the light curve are attributed to tidal distortion caused by a companion. We find problems in the recently proposed and competing explanation of two equal-mass degenerate objects that supposedly will eventually merge, possibly leading to a SN Ia. We conclude that Henize 2-428 cannot be claimed yet to support the double-degenerate scenario for Type Ia supernovae.

  16. Morphological, cellular and proteomic features of canine myxomatous mitral valve disease 

    E-Print Network [OSTI]

    Han, Richard I-Ming

    2009-01-01T23:59:59.000Z

    Myxomatous mitral valve degeneration (MMVD) is the single most common cardiac disease of the dog, and is analogous to Mitral Valve Prolapse in humans. Very little is known about the aetiopathogenesis of this disease or ...

  17. Mechanisms of bioprosthetic heart valve failure: Fatigue causes collagen denaturation and glycosaminoglycan loss

    E-Print Network [OSTI]

    Zand, Robert

    Mechanisms of bioprosthetic heart valve failure: Fatigue causes collagen denaturation heart valve (BPHV) degeneration, characterized by extracellular matrix deterioration, remod- eling) with glutaraldehyde fixed porcine aortic valve bioprostheses, that the mechanical function of cardiac valve cusps

  18. A review of "Bodies, Politics and Transformations: John Donne’s Metempsychosis" by Siobhán Collins

    E-Print Network [OSTI]

    Prescott, Anne Lake

    2014-01-01T23:59:59.000Z

    the Edenic apple’s soul through fifty-two stanzas (weeks?) of degeneration she offers a graduate course on Renaissance vegetables, animals, and human bodies, from the man- drake (a fine pair adorns the cover) to . . . ? Donne hints...

  19. This article was downloaded by: [Hebrew University], [Scott Kirkpatrick] On: 03 December 2011, At: 10:59

    E-Print Network [OSTI]

    Kirkpatrick, Scott

    . The publisher shall not be liable for any loss, actions, claims, proceedings, demand, or costs or damages to highly degenerate low-energy states and hysteretic dynamics, are quite similar to the opposing goals

  20. Segregated Network Polymer-Carbon Nanotubes Composites For Thermoelectrics 

    E-Print Network [OSTI]

    Kim, Dasaroyong

    2010-10-12T23:59:59.000Z

    in polymer technology, particularly nanomaterial-polymer composites, can bring them into degenerate semiconductor or metallic regimes by incorporating a small amount of conductive filler. I demonstrate that such polymer nanocomposites can be viable for light...

  1. Computational regulatory genomics : motifs, networks, and dynamics

    E-Print Network [OSTI]

    Kheradpour, Pouya

    2012-01-01T23:59:59.000Z

    Gene regulation, the process responsible for taking a static genome and producing the diversity and complexity of life, is largely mediated through the sequence specific binding of regulators. The short, degenerate nature ...

  2. 1999 Macmillan Magazines Ltd letters to nature

    E-Print Network [OSTI]

    Coulson, Seana

    . salina were ampli®ed by PCR using cDNAs as templates with degenerate primers to the regions conserved in both C. reinhardtii and A. thaliana CAO sequences. We obtained a CAO cDNA clone of D. salina

  3. alpha beta gamma: Topics by E-print Network

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

    the decoupling limit, M2A0 gg M2Z, the heavy CP-even, CP-odd and charged Higgs boson masses are nearly degenerate, sin(beta-alpha) approaches 1, and the...

  4. Tunnel determinants from spectral zeta functions. Instanton effects in quantum mechanics

    SciTech Connect (OSTI)

    Izquierdo, A. Alonso [Departamento de Matematica Aplicada and IUFFyM, Universidad de Salamanca (Spain); Guilarte, J. Mateos [Departamento de Fisica Fundamental and IUFFyM, Universidad de Salamanca (Spain)

    2014-07-23T23:59:59.000Z

    In this paper we develop an spectral zeta function regularization procedure on the determinants of instanton fluctuation operators that describe the semi-classical order of tunnel effects between degenerate vacua.

  5. Construction BKW en fonds de puits, cas particuliers (Schrodinger, Dirac avec champ

    E-Print Network [OSTI]

    Construction BKW en fonds de puits, cas particuliers (Schr¨odinger, Dirac avec champ magn clefs: semi­classique, puits ponctuel non d'eg'en'er'e, construction BKW , distance d'Agmon, Schr

  6. Proteoglycan 4 metabolism and boundary lubrication of articular cartilage

    E-Print Network [OSTI]

    Schmidt, Tannin A.

    2006-01-01T23:59:59.000Z

    coupling processes is critical for understanding the dynamic processesdynamic processes of cartilage, such as growth, maturation, homeostasis, and degeneration, is elucidating at various levels of detail the chemomechanical coupling

  7. Effects of lactose and mode of sterilization of a lactose diet on mineral metabolism in germ-free

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    p. 100 of lactose (L). The diet was sterilized either by irradiation (I) or by autoclave (Au. These substances affect food intake, reduce nitrogen digestion and cause hepatic degeneration, renal hypertrophy

  8. White Dwarfs in Binary Systems A white dwarf orbiting another star can become active

    E-Print Network [OSTI]

    Barnes, Joshua Edward

    Novae When enough has accumulated, the H burns violently, producing a thermonuclear explosion in its degenerate center, and a thermonuclear explosion completely destroys the star. #12;3-D Simulation

  9. Trotter's product formula for projections

    E-Print Network [OSTI]

    Shvydkoy, Roman

    -semigroup etB is replaced by the simplest of degenerate semigroups, i.e. a projection P L P denotes a bounded projection. Now, in (1) we replace the C0-semigroup etB by the continuous

  10. Proof of a Conjecture by Lewandowski and Thiemann

    E-Print Network [OSTI]

    Christian Fleischhack

    2003-04-01T23:59:59.000Z

    It is proven that for compact, connected and semisimple structure groups every degenerate labelled web is strongly degenerate. This conjecture by Lewandowski and Thiemann implies that diffeomorphism invariant operators in the category of piecewise smooth immersive paths preserve the decomposition of the space of integrable functions w.r.t. the degeneracy and symmetry of the underlying labelled webs. This property is necessary for lifting these operators to well-defined operators on the space of diffeomorphism invariant states.

  11. Diagrammatic Approach to Quantum Search

    E-Print Network [OSTI]

    Thomas G. Wong

    2015-02-09T23:59:59.000Z

    We introduce a simple diagrammatic approach for estimating how a randomly walking quantum particle searches on a graph in continuous-time, which involves sketching small weighted graphs with self-loops and considering degenerate perturbation theory's effects on them. Using this method, we give the first example of degenerate perturbation theory solving search on a graph whose evolution occurs in a subspace whose dimension grows with $N$.

  12. A New Type of Resonant Neutrino Conversions Induced by Magnetic Fields

    E-Print Network [OSTI]

    S. Sahu; V. B. Semikoz; J. W. F. Valle

    1995-12-21T23:59:59.000Z

    We consider resonant neutrino conversions in magnetised matter, such as a degenerate electron gas. We show how magnetisation effects caused by axial vector interactions of neutrinos with the charged leptons in the medium can induce a new type of resonant neutrino conversion which may occur even in situations where the MSW effect does not occur, such as the case of degenerate or inverted neutrino mass spectra. Our new resonance may simultaneously affect anti-neutrino $\\bar{\

  13. Quantum dynamics and macroscopic quantum tunneling of two weakly coupled condensates

    E-Print Network [OSTI]

    René John Kerkdyk; S. Sinha

    2012-09-24T23:59:59.000Z

    We study the quantum dynamics of a Bose Josephson junction(BJJ) made up of two coupled Bose-Einstein condensates. Apart from the usual ac Josephson oscillations, two different dynamical states of BJJ can be observed by tuning the inter-particle interaction strength, which are known as '$\\pi$-oscillation' with relative phase $\\pi$ between the condensates and 'macroscopic self-trapped' (MST) state with finite number imbalance. By choosing appropiate intial state we study above dynamical branches quantum mechanically and compare with classical dynamics. The stability region of the '$\\pi$-oscillation' is separated from that of 'MST' state at a critical coupling strength. Also a significant change in the energy spectrum takes place above the critical coupling strength, and pairs of (quasi)-degenerate excited states appear. The original model of BJJ can be mapped on to a simple Hamiltonian describing quantum particle in an 'effective potential' with an effective Planck constant. Different dynamical states and degenerate excited states in the energy spectrum can be understood in this 'effective potential' approach. Also possible novel quantum phenomena like 'macroscopic quantum tunneling'(MQT) become evident from the simple picture of 'effective potential'. We study decay of metastable '$\\pi$-oscillation' by MQT through potential barrier. The doubly degenerate excited states in the energy spectrum are associated with the classically degenerate MST states with equal and opposite number imbalance. We calculate the energy splitting between these quasi-degenerate excited states due to MQT of the condensate between classically degenerate MST states.

  14. ORIGINAL ARTICLE A theoretical analysis of the relative influences of peak BMD,

    E-Print Network [OSTI]

    Stanford University

    loss and menopause on the development of osteoporosis C.J. Hernandez Æ G.S. Beaupre´ Æ D.R. Carter Osteoporosis Foundation and National Osteoporosis Foundation 2003 Abstract Factors that determine a post-menopausal the relative influences of peak BMD, menopause and age- related bone loss on the development of osteoporosis

  15. COM: A Method for Mining and Monitoring Human Activity Patterns in Home-based Health Monitoring Systems

    E-Print Network [OSTI]

    Cook, Diane J.

    for the health care system due to the shortage of health care professionals and health care facilities. To remedy population in the coming decades will result in many complications for families, society and the government, such as the shortage of health care professionals and care facilities, an increase in age related diseases and rising

  16. COMPARISON OF OPTICAL COHERENCE TOMOGRAPHY IMAGING OF CATARACTS

    E-Print Network [OSTI]

    Boppart, Stephen

    of Texas, Austin, Texas; Radiofrequency Radiation Division, Armstrong Laboratory, Brooks AFB, Texas (Paper), with documented cataracts. These monkeys were exposed to several types of radiation during the mid and late 1960s. The radiation and age related cataracts in these animals were closely monitored using a unique grading system

  17. Regulatory instrument review: Aging management of LWR cables, containment and basemat, reactor coolant pumps, and motor-operated valves

    SciTech Connect (OSTI)

    Werry, E.V.; Somasundaram, S.

    1995-09-01T23:59:59.000Z

    The results of Stage 2 of the Regulatory Instrument Review are presented in this volume. Selected regulatory instruments, such as the Code of Federal Regulations (CFR), US Nuclear Regulatory Commission (NRC), Regulatory Guides, and ASME Codes, were investigated to determine the extent to which these regulations apply aging management to selected safety-related components in nuclear power plants. The Regulatory Instrument Review was funded by the NRC under the Nuclear Plant Aging Research (NPAR) program. Stage 2 of the review focused on four safety-related structures and components; namely, cables, containment and basemat, reactor coolant pumps, and motor-operated valves. The review suggests that the primary-emphasis of the regulatory instruments was on the design, construction, start-up, and operation of a nuclear power plant, and that aging issues were primarily addressed after an aging-related problem was recognized. This Stage 2 review confirms the results of the prior review; (see Regulatory Instrument Review: Management of Aging of LWR Major Safety-Related Components NUREG/CR-5490. The observations indicate that the regulations generally address management of age-related degradation indirectly. Specific age-related degradation phenomena frequently are dealt with in bulletins and notices or through generic issues, letters, etc. The major recommendation of this report, therefore, is that the regulatory instruments should more directly and explicitly address the aging phenomenon and the management of the age-related degradation process.

  18. IEEE Workshop on Emergent Technologies and Virtual Systems for Instrumentation and Measurement

    E-Print Network [OSTI]

    Siegel, Mel

    School of Electrical and Computer Engineering Carnegie Mellon University Pittsburgh PA 15213 USA Phone, and skin are all subject to a variety of load and age related problems. Our work focuses on finding skin: an ``island hopping'' airline with many short low altitude flights, an airplane with an unusually high number

  19. IEEE Workshop on Emergent Technologies and Virtual Systems for Instrumentation and Measurement

    E-Print Network [OSTI]

    Siegel, Mel

    of Electrical and Computer Engineering Carnegie Mellon University Pittsburgh PA 15213 USA Phone 412 268 8802 Fax subject to a variety of load and age related problems. Our work focuses on finding skin cracks" is generally attributed[1] to an unusual and unfortunate combination of circumstances: an "island hopping

  20. BioMed Central Page 1 of 18

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    AccessReview Medical bioremediation of age-related diseases Jacques M Mathieu*1, John Schloendorn2, Bruce homeostasis. Another alternative is "medical bioremediation," the use of microbial enzymes to augment missing insufficient catabolic functions [5]. Medical bioremediation can be considered as an extension of envi

  1. What is presbyopia? Presbyopia is a common type of vision disorder

    E-Print Network [OSTI]

    Bandettini, Peter A.

    the age of 40 to check for age-related conditions. How is presbyopia corrected? Eyeglasses are the simplest and safest means of correcting presbyopia. Eyeglasses for presbyopia have higher focusing power distant objects through the upper portion of the lens. It is also possible to purchase reading eyeglasses

  2. Why do seizures occur when they do? Situations perceived to be associated with increased or decreased seizure likelihood in people withepilepsy and intellectual disability

    E-Print Network [OSTI]

    Illingworth, Josephine L.; Watson, Peter; Ring, Howard

    2014-09-16T23:59:59.000Z

    , Pascotto A, et al. Polysomnographic findings in Rett syndrome: a case–control study. Sleep Breath 2013;17:93–8. [46] Ellaway C, Peat J, Leonard H, Christodoulou J. Sleep dysfunction in Rett syndrome: lack of age related decrease in sleep duration. Brain Dev...

  3. Accident Analysis and Prevention 42 (2010) 364371 Contents lists available at ScienceDirect

    E-Print Network [OSTI]

    Boggess, May M.

    2010-01-01T23:59:59.000Z

    Accident Analysis and Prevention 42 (2010) 364­371 Contents lists available at ScienceDirect Accident Analysis and Prevention journal homepage: www.elsevier.com/locate/aap Review Age-related safety Keywords: Age factors Truck Traffic accidents/crashes Occupation Safety Statistics a b s t r a c

  4. Telomere length in circulating leukocytes is associated with lung function and

    E-Print Network [OSTI]

    Nyholt, Dale R.

    Telomere length in circulating leukocytes is associated with lung function and disease Eva Albrecht intrinsic age-related processes contribute to the interindividual variability of lung function. Our meta-analysis of 14 studies included 934 COPD cases with 15846 controls defined according to the Global Lungs

  5. Asymptotic properties of linear field equations in anti-de Sitter space

    E-Print Network [OSTI]

    Holzegel, Gustav; Smulevici, Jacques; Warnick, Claude

    2015-01-01T23:59:59.000Z

    We study the global dynamics of the wave equation, Maxwell's equation and the linearized Bianchi equations on a fixed anti-de Sitter (AdS) background. Provided dissipative boundary conditions are imposed on the dynamical fields we prove uniform boundedness of the natural energy as well as both degenerate (near the AdS boundary) and non-degenerate integrated decay estimates. Remarkably, the non-degenerate estimates "lose a derivative". We relate this loss to a trapping phenomenon near the AdS boundary, which itself originates from the properties of (approximately) gliding rays near the boundary. Using the Gaussian beam approximation we prove that non-degenerate energy decay without loss of derivatives does not hold. As a consequence of the non-degenerate integrated decay estimates, we also obtain pointwise-in-time decay estimates for the energy. Our paper provides the key estimates for a proof of the non-linear stability of the anti-de Sitter spacetime under dissipative boundary conditions. Finally, we contras...

  6. Electrostatic solitary ion waves in dense electron-positron-ion magnetoplasma

    SciTech Connect (OSTI)

    Jehan, Nusrat [Department of Physics, Theoretical Plasma Physics Group, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Pakistan Atomic Energy Commission, P.O. Box 1114, Islamabad 44000 (Pakistan); Salahuddin, M. [Pakistan Atomic Energy Commission, P.O. Box 1114, Islamabad 44000 (Pakistan); Mahmood, S. [Theoretical Plasma Physics Division, PINSTECH, P.O. Nilore, Islamabad 44000 (Pakistan); Mirza, Arshad M. [Department of Physics, Theoretical Plasma Physics Group, Quaid-i-Azam University, Islamabad 45320 (Pakistan)

    2009-04-15T23:59:59.000Z

    The nonlinear coupled ion-acoustic and ion-cyclotron waves propagating obliquely to the external magnetic field in dense collisionless electron-positron-ion magnetoplasma are investigated using Sagdeev potential method. A semiclassical approach is used. Electrons and positrons are treated as degenerate Fermi gases described by Thomas-Fermi density distribution and ions behave as classical gas. It is found that the presence of degenerate positrons in a dense Thomas-Fermi plasma significantly modifies the structure of solitary waves by restricting the electrostatic potential to a certain maximum value which depends upon the concentration of positrons in the system. It is also noted that only subsonic humplike solitary waves can exist and for a given angle of propagation, the presence of degenerate positrons diminishes the amplitude as well as width of the solitary wave.

  7. Two-loop Yang-Mills diagrams from superstring amplitudes

    E-Print Network [OSTI]

    Magnea, Lorenzo; Russo, Rodolfo; Sciuto, Stefano

    2015-01-01T23:59:59.000Z

    Starting from the superstring amplitude describing interactions among D-branes with a constant world-volume field strength, we present a detailed analysis of how the open string degeneration limits reproduce the corresponding field theory Feynman diagrams. A key ingredient in the string construction is represented by the twisted (Prym) super differentials, as their periods encode the information about the background field. We provide an efficient method to calculate perturbatively the determinant of the twisted period matrix in terms of sets of super-moduli appropriate to the degeneration limits. Using this result we show that there is a precise one-to-one correspondence between the degeneration of different factors in the superstring amplitudes and one-particle irreducible Feynman diagrams capturing the gauge theory effective action at the two-loop level.

  8. Modulation of drift-wave envelopes in a nonuniform quantum magnetoplasma

    SciTech Connect (OSTI)

    Misra, A. P., E-mail: apmisra@visva-bharati.ac.in, E-mail: apmisra@gmail.com [Department of Mathematics, Siksha Bhavana, Visva-Bharati University, Santiniketan-731 235, West Bengal (India)

    2014-04-15T23:59:59.000Z

    We study the amplitude modulation of low-frequency, long-wavelength electrostatic drift-wave envelopes in a nonuniform quantum magnetoplasma consisting of cold ions and degenerate electrons. The effects of tunneling associated with the quantum Bohm potential and the Fermi pressure for nonrelativistic degenerate electrons, as well as the equilibrium density and magnetic field inhomogeneities are taken into account. Starting from a set of quantum magnetohydrodynamic equations, we derive a nonlinear Schrödinger equation (NLSE) that governs the dynamics of the modulated quantum drift-wave packets. The NLSE is used to study the modulational instability (MI) of a Stoke's wave train to a small plane wave perturbation. It is shown that the quantum tunneling effect as well as the scale length of inhomogeneity plays crucial roles for the MI of the drift-wave packets. Thus, the latter can propagate in the form of bright and dark envelope solitons or as drift-wave rogons in degenerate dense magnetoplasmas.

  9. Axion emission from a magnetized neutron gas

    SciTech Connect (OSTI)

    Skobelev, V. V., E-mail: v.skobelev@inbox.ru [Moscow State Industrial University (Russian Federation)

    2011-01-15T23:59:59.000Z

    By using the polarization density matrix for a neutron in a magnetic field, the axion luminosity of magnetic neutron stars that is associated with the flip of the anomalous magnetic moment of degenerate nonrelativistic neutrons is calculated. It is shown that, at values of the magnetic-field induction in the region B Greater-Than-Or-Equivalent-To 10{sup 18} G, this mechanism of axion emission is dominant in 'young' neutron stars of temperature about a few tens of MeV units. At B {approx} 10{sup 17} G, it is one of the basic mechanisms. The Fermi energy of a degenerate neutron gas in a magnetic field is found, and it is shown that there is no such mechanism of axion emission in the degenerate case.

  10. Two-dimensional cylindrical ion-acoustic solitary and rogue waves in ultrarelativistic plasmas

    SciTech Connect (OSTI)

    Ata-ur-Rahman [Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan) [Institute of Physics and Electronics, University of Peshawar, Peshawar 25000 (Pakistan); National Centre for Physics at QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan); Ali, S. [National Centre for Physics at QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan)] [National Centre for Physics at QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan); Moslem, W. M. [Department of Physics, Faculty of Science, Port Said University, Port Said 42521 (Egypt)] [Department of Physics, Faculty of Science, Port Said University, Port Said 42521 (Egypt); Mushtaq, A. [National Centre for Physics at QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan) [National Centre for Physics at QAU Campus, Shahdrah Valley Road, Islamabad 44000 (Pakistan); Department of Physics, Abdul Wali Khan University, Mardan 23200 (Pakistan)

    2013-07-15T23:59:59.000Z

    The propagation of ion-acoustic (IA) solitary and rogue waves is investigated in a two-dimensional ultrarelativistic degenerate warm dense plasma. By using the reductive perturbation technique, the cylindrical Kadomtsev–Petviashvili (KP) equation is derived, which can be further transformed into a Korteweg–de Vries (KdV) equation. The latter admits a solitary wave solution. However, when the frequency of the carrier wave is much smaller than the ion plasma frequency, the KdV equation can be transferred to a nonlinear Schrödinger equation to study the nonlinear evolution of modulationally unstable modified IA wavepackets. The propagation characteristics of the IA solitary and rogue waves are strongly influenced by the variation of different plasma parameters in an ultrarelativistic degenerate dense plasma. The present results might be helpful to understand the nonlinear electrostatic excitations in astrophysical degenerate dense plasmas.

  11. Efficient all-optical production of large $^6$Li quantum gases using D$_1$ gray-molasses cooling

    E-Print Network [OSTI]

    A. Burchianti; G. Valtolina; J. A. Seman; E. Pace; M. De Pas; M. Inguscio; M. Zaccanti; G. Roati

    2014-06-18T23:59:59.000Z

    We use a gray molasses operating on the D$_1$ atomic transition to produce degenerate quantum gases of $^{6}$Li with a large number of atoms. This sub-Doppler cooling phase allows us to lower the initial temperature of 10$^9$ atoms from 500 to 40 $\\mu$K in 2 ms. We observe that D$_1$ cooling remains effective into a high-intensity infrared dipole trap where two-state mixtures are evaporated to reach the degenerate regime. We produce molecular Bose-Einstein condensates of up to 5$\\times$10$^{5}$ molecules and weakly-interacting degenerate Fermi gases of $7\\times$10$^{5}$ atoms at $T/T_{F}<0.1$ with a typical experimental duty cycle of 11 seconds.

  12. Relativistic harmonic oscillator model for quark stars

    E-Print Network [OSTI]

    Vishnu M. Bannur

    2008-10-06T23:59:59.000Z

    The relativistic harmonic oscillator (RHO) model of hadrons is used to study quark stars. The mass-radius relationship is obtained and compared with bag model of quark star, using Tolman-Oppenheimer-Volkoff equation. In this model, the outward degenerate pressure due to discrete Landau levels and Landau degeneracy balances the inward gravitational pressure. Where as in bag model the degenerate pressure is due to the standard continuum levels which balances the combined inward pressure due to gravitation and bag pressure. So in RHO model, the confinement effect is included in the degenerate pressure. We found a qualitative similarity, but quantitative differences in mass-radius relationship of quark stars in these two models. Masses and radii are relatively larger and the central energy densities, required for stable quark stars, are lower in RHO model than that of bag model.

  13. The effect of dinitrophenol on the development and oxidative metabolism of the chick embryo

    E-Print Network [OSTI]

    Feldman, Gerald Lewis

    1959-01-01T23:59:59.000Z

    degeneration and liquefaction of the lens proteins. Small focal areas of degeneration -were observed in the cortex of the lens and were considered as Morgagni bodies (Figure 4 ) 0 In addition to the degenerative changes, there was an apparent movement..., and 1000 meg . 5 and those injected on the fifteenth day received 750 and 1000 meg, of the drug respectively. The eggs were prepared for injection by painting a small area over the air cell of the egg with tincture of merthiolate. A small hole was 6...

  14. What role does the third law of thermodynamics play in Szilard engines?

    E-Print Network [OSTI]

    Kang-Hwan Kim; Sang Wook Kim

    2011-12-14T23:59:59.000Z

    The role of the third law of thermodynamics in the Szilard engine has been addressed. If the ground state is non-degenerate, the entropy production defined as the work extractable from the engine divided by temperature vanishes as temperature approaches zero due to the third law. The degenerate ground state induced by the symmetry or by accidence gives rise to non-zero entropy production at zero temperature associated with the residual entropy. Various physical situations such as the SZE consisting of bosons or fermions either with or without interaction have been investigated.

  15. Method for resonant measurement

    DOE Patents [OSTI]

    Rhodes, G.W.; Migliori, A.; Dixon, R.D.

    1996-03-05T23:59:59.000Z

    A method of measurement of objects to determine object flaws, Poisson`s ratio ({sigma}) and shear modulus ({mu}) is shown and described. First, the frequency for expected degenerate responses is determined for one or more input frequencies and then splitting of degenerate resonant modes are observed to identify the presence of flaws in the object. Poisson`s ratio and the shear modulus can be determined by identification of resonances dependent only on the shear modulus, and then using that shear modulus to find Poisson`s ratio using other modes dependent on both the shear modulus and Poisson`s ratio. 1 fig.

  16. A (P)HMC algorithm for N_f = 2 + 1 + 1 flavours of twisted mass fermions

    E-Print Network [OSTI]

    T. Chiarappa; R. Frezzotti; C. Urbach

    2005-09-27T23:59:59.000Z

    We present a detailed design of a (P)HMC simulation algorithm for N_f = 2 + 1 + 1 maximally twisted Wilson quark flavours. The algorithm retains even/odd and mass-shift preconditionings combined with multiple Molecular Dynamics time scales for both the light mass degenerate, u and d, quarks and the heavy mass non-degenerate, s and c, quarks. Various non-standard aspects of the algorithm are discussed, among which those connected to the use of a polynomial approximation for the inverse (square root of the squared) Dirac matrix in the s and c quark sector.

  17. Pion mass effects on axion emission from neutron stars through NN bremsstrahlung processes

    E-Print Network [OSTI]

    S. Stoica; B. Pastrav; J. E. Horvath; M. P. Allen

    2009-11-30T23:59:59.000Z

    The rates of axion emission by nucleon-nucleon bremsstrahlung are calculated with the inclusion of the full momentum contribution from a nuclear one pion exchange (OPE) potential. The contributions of the neutron-neutron (nn), proton-proton (pp) and neutron-proton (np) processes in both the nondegenerate and degenerate limits are explicitly given. We find that the finite momentum corrections to the emissivities are quantitatively significant for the non-degenerate regime and temperature-dependent, and should affect the existing axion mass bounds. The trend of these nuclear effects is to diminish the emissivities.

  18. Study of stopping power for a proton moving in a plasma with arbitrary degeneracy

    SciTech Connect (OSTI)

    Zhang, Ya; Song, Yuan-Hong; Wang, You-Nian [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)] [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2013-10-15T23:59:59.000Z

    Excitation of bulk solid electrons with arbitrary degeneracy, by external charged particles, is investigated by a two-dimensional nonlinear quantum hydrodynamic (QHD) model. The nonlinear stopping power and wake potential are calculated by solving the nonlinear QHD equations with the flux corrected transport numerical method. Two cases of fully degenerated and partially degenerated electrons are compared and discussed in the same self-consistent QHD model. Our results are consistent with the well known dielectric calculation of the stopping power at higher velocity, but include the nonlinear terms of the interactions and give larger stopping power at smaller velocity.

  19. Producing and Detecting Correlated atoms

    E-Print Network [OSTI]

    Christoph I. Westbrook; Martijn Schellekens; Aurélien Perrin; Valentina Krachmalnicoff; Jose Carlos Viana Gomes; Jean-Baptiste Trebbia; Jérôme Estève; Hong Chang; Isabelle Bouchoule; Denis Boiron; Alain Aspect; Tom Jeltes; John McNamara; Wim Hogervorst; Wim Vassen

    2006-09-04T23:59:59.000Z

    We discuss experiments to produce and detect atom correlations in a degenerate or nearly degenerate gas of neutral atoms. First we treat the atomic analog of the celebrated Hanbury Brown Twiss experiment, in which atom correlations result simply from interference effects without any atom interactions.We have performed this experiment for both bosons and fermions. Next we show how atom interactions produce correlated atoms using the atomic analog of spontaneous four-wavemixing. Finally, we briefly mention experiments on a one dimensional gas on an atom chip in which correlation effects due to both interference and interactions have been observed.

  20. Quantum effects in electron beam pumped GaAs

    SciTech Connect (OSTI)

    Yahia, M. E. [Faculty of Engineering, The British University in Egypt (BUE), El-Shorouk City, Cairo (Egypt) [Faculty of Engineering, The British University in Egypt (BUE), El-Shorouk City, Cairo (Egypt); National Institute of Laser Enhanced Sciences (NILES), Cairo University (Egypt); Azzouz, I. M. [National Institute of Laser Enhanced Sciences (NILES), Cairo University (Egypt)] [National Institute of Laser Enhanced Sciences (NILES), Cairo University (Egypt); Moslem, W. M. [Department of Physics, Faculty of Science, Port Said University, Port Said (Egypt)] [Department of Physics, Faculty of Science, Port Said University, Port Said (Egypt)

    2013-08-19T23:59:59.000Z

    Propagation of waves in nano-sized GaAs semiconductor induced by electron beam are investigated. A dispersion relation is derived by using quantum hydrodynamics equations including the electrons and holes quantum recoil effects, exchange-correlation potentials, and degenerate pressures. It is found that the propagating modes are instable and strongly depend on the electron beam parameters, as well as the quantum recoil effects and degenerate pressures. The instability region shrinks with the increase of the semiconductor number density. The instability arises because of the energetic electron beam produces electron-hole pairs, which do not keep in phase with the electrostatic potential arising from the pair plasma.

  1. High-resolution inverse Raman and resonant-wave-mixing spectroscopy

    SciTech Connect (OSTI)

    Rahn, L.A. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01T23:59:59.000Z

    These research activities consist of high-resolution inverse Raman spectroscopy (IRS) and resonant wave-mixing spectroscopy to support the development of nonlinear-optical techniques for temperature and concentration measurements in combustion research. Objectives of this work include development of spectral models of important molecular species needed to perform coherent anti-Stokes Raman spectroscopy (CARS) measurements and the investigation of new nonlinear-optical processes as potential diagnostic techniques. Some of the techniques being investigated include frequency-degenerate and nearly frequency-degenerate resonant four-wave-mixing (DFWM and NDFWM), and resonant multi-wave mixing (RMWM).

  2. Level Structure of 103Ag at high spins

    E-Print Network [OSTI]

    S. Ray; N. S. Pattabiraman; Krishichayan; A. Chakraborty; S. Mukhopadhyay; S. S. Ghugre; S. N. Chintalapudi; A. K. Sinha; U. Garg; S. Zhu; B. Kharraja; D. Almehed

    2007-12-07T23:59:59.000Z

    High spin states in $^{103}$Ag were investigated with the Gammasphere array, using the $^{72}$Ge($^{35}$Cl,$2p2n$)$^{103}$Ag reaction at an incident beam energy of 135 MeV. A $\\Delta J$=1 sequence with predominantly magnetic transitions and two nearly-degenerate $\\Delta J=1$ doublet bands have been observed. The dipole band shows a decreasing trend in the $B(M1)$ strength as function of spin, a well established feature of magnetic bands. The nearly-degenerate band structures satisfy the three experimental signatures of chirality in the nuclei; however microscopic calculations are indicative of a magnetic phenomenon

  3. Image analysis of ocular fundus for retinopathy characterization

    SciTech Connect (OSTI)

    Ushizima, Daniela; Cuadros, Jorge

    2010-02-05T23:59:59.000Z

    Automated analysis of ocular fundus images is a common procedure in countries as England, including both nonemergency examination and retinal screening of patients with diabetes mellitus. This involves digital image capture and transmission of the images to a digital reading center for evaluation and treatment referral. In collaboration with the Optometry Department, University of California, Berkeley, we have tested computer vision algorithms to segment vessels and lesions in ground-truth data (DRIVE database) and hundreds of images of non-macular centric and nonuniform illumination views of the eye fundus from EyePACS program. Methods under investigation involve mathematical morphology (Figure 1) for image enhancement and pattern matching. Recently, we have focused in more efficient techniques to model the ocular fundus vasculature (Figure 2), using deformable contours. Preliminary results show accurate segmentation of vessels and high level of true-positive microaneurysms.

  4. Nondestructive ultrasonic testing of materials

    DOE Patents [OSTI]

    Hildebrand, Bernard P. (Richland, WA)

    1994-01-01T23:59:59.000Z

    Reflection wave forms obtained from aged and unaged material samples can be compared in order to indicate trends toward age-related flaws. Statistical comparison of a large number of data points from such wave forms can indicate changes in the microstructure of the material due to aging. The process is useful for predicting when flaws may occur in structural elements of high risk structures such as nuclear power plants, airplanes, and bridges.

  5. LWR Sustainability: Assessment of Aging of Nuclear Power Plant Safety Related Concrete Strutures

    SciTech Connect (OSTI)

    Graves III, Herman [U.S. Nuclear Regulatory Commission; Naus, Dan J [ORNL

    2013-01-01T23:59:59.000Z

    Current regulatory testing and inspection requirements are reviewed and a summary of degradation experience is presented. Techniques commonly used to inspect NPP concrete structures to assess and quantify age-related degradation are summarized. An approach for conduct of condition assessments of structures in NPPs is presented. Criteria, based primarily on visual indications, are provided for use in classification and assessment of concrete degradation. Materials and techniques for repair of degraded structures are generally discussed.

  6. Nondestructive ultrasonic testing of materials

    DOE Patents [OSTI]

    Hildebrand, B.P.

    1994-08-02T23:59:59.000Z

    Reflection wave forms obtained from aged and unaged material samples can be compared in order to indicate trends toward age-related flaws. Statistical comparison of a large number of data points from such wave forms can indicate changes in the microstructure of the material due to aging. The process is useful for predicting when flaws may occur in structural elements of high risk structures such as nuclear power plants, airplanes, and bridges. 4 figs.

  7. Reaction-Diffusion systems for the macroscopic Bidomain model of the cardiac electric field

    E-Print Network [OSTI]

    Veneroni, Marco

    Reaction-Diffusion systems for the macroscopic Bidomain model of the cardiac electric field Marco Veneroni Abstract. The paper deals with a mathematical model for the electric activity of the heart the mathematical viewpoint the model is made up of a degenerate parabolic reaction diffusion system coupled

  8. Thermal Density Functional Theory in Context Aurora Pribram-Jones,

    E-Print Network [OSTI]

    Burke, Kieron

    .3. Consequences 4 III.2.4. Extension to degenerate ground states 4 III.3. Kohn-Sham scheme 5 III.3.1. Exchange [1], and the various methods for modeling it are di- verse [2­4]. The field includes enormous with useful accuracy. It is important to understand, from the outset, that the logic and methodology of KS

  9. GENERIC FEEDBACK: 2014 MATH 34032 EXAM (1) (a) Not very many people managed to find the correct adjoint boundary condition

    E-Print Network [OSTI]

    Sidorov, Nikita

    GENERIC FEEDBACK: 2014 MATH 34032 EXAM (1) (a) Not very many people managed to find the correct. (2) (a) Many people tried to introduce both c1 and c2. Since the degenerate kernel in this case has know what the adjoint problem is. Not very many people seemed to realise this. (c) Very few people

  10. Observation of the memory steps in graphene at elevated temperatures Sergey L. Rumyantsev,1,2

    E-Print Network [OSTI]

    layers were sequentially deposited on graphene by the electron-beam evaporation to produce the drain and source contacts.8,9 The degenerately doped Si sub- strate acted as a back gate. The current-voltage I-V charac- teristics drain current versus gate voltage were measured using a semiconductor parameter

  11. Observation of the Memory Steps in Graphene at Elevated Temperatures

    E-Print Network [OSTI]

    were sequentially deposited on graphene by the electron-beam evaporation to produce the drain and source contacts.[8,9] The degenerately doped Si substrate acted as a back gate. The current­voltage (I-V) characteristics (drain current versus gate voltage) were measured using a semiconductor parameter analyzer

  12. Incorporating WAAS Data Into an Ionospheric Model for Correcting Satellite Radar

    E-Print Network [OSTI]

    Toews, Carl

    at the Millstone Hill Satellite Tracking Radar. She currently holds a joint appointment with the Atmospheric corrections to radar measurements, incorporating data from a single receiver to generate TEC estimates that the GRIMS ionospheric model degenerates during times of sharp spatial TEC gradients, e.g. during geomagnetic

  13. Asymptotic analysis of the EPRL four-simplex amplitude

    E-Print Network [OSTI]

    John W. Barrett; R. J. Dowdall; Winston J. Fairbairn; Henrique Gomes; Frank Hellmann

    2009-04-20T23:59:59.000Z

    The semiclassical limit of a 4-simplex amplitude for a spin foam quantum gravity model with an Immirzi parameter is studied. If the boundary state represents a non-degenerate 4-simplex geometry, the asymptotic formula contains the Regge action for general relativity. A canonical choice of phase for the boundary state is introduced and is shown to be necessary to obtain the results.

  14. PUBLISHED ONLINE: 20 SEPTEMBER 2009 | DOI: 10.1038/NPHYS1364 Superfluidity of polaritons in semiconductor

    E-Print Network [OSTI]

    Loss, Daniel

    defects when the flow velocity is slower than the speed of sound in the fluid. Moreover, a Cerenkov-like wake pattern is observed when the flow velocity exceeds the speed of sound. The experimental findings in degenerate gases of interacting bosons. Since its first discovery in liquid helium-4 (refs 1, 2

  15. Cosmic Supernova Rate History and Type Ia Supernova Progenitors

    E-Print Network [OSTI]

    Chiaki Kobayashi; Ken'ichi Nomoto; Takuji Tsujimoto

    2001-02-14T23:59:59.000Z

    Adopting a single degenerate scenario for Type Ia supernova progenitors with the metallicity effect, we make a prediction of the cosmic supernova rate history as a composite of the supernova rates in spiral and elliptical galaxies, and compare with the recent observational data up to z ~ 0.55.

  16. VOLUME 84, NUMBER 3 P H Y S I C A L R E V I E W L E T T E R S 17 JANUARY 2000 Beyond Optical Molasses: 3D Raman Sideband Cooling of Atomic Cesium

    E-Print Network [OSTI]

    Vuletic, Vladan

    . The technique is based on 3D degenerate Raman sideband cooling in optical lattices and remains efficient even [1]. Although other techniques, such as evaporative cooling [2], velocity-selective coherent Molasses: 3D Raman Sideband Cooling of Atomic Cesium to High Phase-Space Density Andrew J. Kerman, Vladan

  17. arXiv:1110.4067v1[cond-mat.quant-gas]18Oct2011 Low-temperature, high-density magneto-optical trapping of potassium

    E-Print Network [OSTI]

    Thywissen, Joseph

    for the study of quantum degenerate Fermi gases, new cooling techniques would be beneficial. Laser cooling Sciences, University of Toronto, M5S1A7 Canada (Dated: October 19, 2011) We report the laser cooling density over our 767 nm MOT, showing enhanced pre-cooling for quantum gas experiments. A qualitatively

  18. arXiv:hep-th/0102039v17Feb2001 AN -type Dunkl operators and new spin CalogeroSutherland models

    E-Print Network [OSTI]

    Zhdanov, Renat

    N ). (2) Using the relations K2 ij = 1, KijKjk = KikKij = KjkKik, KijKkl = KklKij, (3) where i, j, k, l (1) and prove that Ti, Kjk, i, j, k = 1, . . . , N, span a realization of a degenerate On leave

  19. A CONVERGENT ADAPTIVE FINITE ELEMENT METHOD FOR AN OPTIMAL DESIGN PROBLEM

    E-Print Network [OSTI]

    Bartels, Soeren

    of given geometry and unknown distribution of two materials of prescribed amounts is one model example in topology optimisation. It eventually leads to a degenerated convex minimisation problem. The numerical to refine everywhere. Its convergence proof is therefore based on energy estimates and some refined

  20. Small entries of neutrino mass matrices

    E-Print Network [OSTI]

    E. Kh. Akhmedov

    1999-09-15T23:59:59.000Z

    We consider phenomenologically allowed structures of the neutrino mass matrix in the case of three light neutrino species. Constraints from the solar, atmospheric and reactor neutrino experiments as well as those from the neutrinoless double beta decay are taken into account. Both hierarchical and quasi-degenerate neutrino mass cases are studied. Assuming maximal $\

  1. Singlet Free Energies of a Static Quark-Antiquark Pair

    E-Print Network [OSTI]

    Konstantin Petrov

    2004-09-01T23:59:59.000Z

    We study the singlet part of the free energy of a static quark anti-quark pair at finite temperature in three flavor QCD with degenerate quark masses using $N_{\\tau}=4$ and 6 lattices with Asqtad staggered fermion action. We look at thermodynamics of the system around phase transition and study its scaling with lattice spacing and quark masses.

  2. Higgs boson resonance parameters and the finite temperature phase transition in a chirally invariant Higgs-Yukawa model

    E-Print Network [OSTI]

    John Bulava; Philip Gerhold; Karl Jansen; Jim Kallarackal; Attila Nagy

    2011-11-11T23:59:59.000Z

    We study a chirally invariant Higgs-Yukawa model regulated on a space-time lattice. We calculate Higgs boson resonance parameters and mass bounds for various values of the mass of the degenerate fermion doublet. Also, first results on the phase transition temperature are presented. In general, this model may be relevant for BSM scenarios with a heavy fourth generation of quarks.

  3. Project #8: Zigang Ge and Robert Guldberg: Cartilage Regeneration with Functional Biomaterials and Quantitative Assessment of Regeneration

    E-Print Network [OSTI]

    Weber, Rodney

    Project #8: Zigang Ge and Robert Guldberg: Cartilage Regeneration with Functional Biomaterials from Georgia Institute of Technology and the GE lab from Peking University. The proposed collaboration the development of effective strategies for functional restoration of degenerated articular joints. Ge's lab

  4. SU4228472 Simpson's Neutrino and the Singular SeeSaw

    E-Print Network [OSTI]

    Allen, Theodore J.

    Burjassot, Valâ??encia, Spain Abstract We derive explicit forms for the neutrino and lepton ``mixing­matrices ``natural'') massive neutrino in gauge theories is of the two­component ``Majorana'' type, it becomes Majorana neutrinos whose contributions cancel each other. If the two are degenerate, or nearly so, they e

  5. Design of CMOS integrated frequency synthesizers for ultra-wideband wireless communications systems

    E-Print Network [OSTI]

    Tong, Haitao

    2009-05-15T23:59:59.000Z

    on the capacitive source degeneration structure. The QVCO tackles the jeopardous ambiguity of the oscillation frequency in conventional QVCOs. Measurement shows that the 5¬GHz CSD¬QVCO in 0.18 µm CMOS technology draws 5.2 mA current from a 1.2 V power supply. Its...

  6. HIGH-RESOLUTION FINITE VOLUME METHODS FOR DUSTY GAS JETS AND MARICA PELANTI AND RANDALL J. LEVEQUE

    E-Print Network [OSTI]

    LeVeque, Randy

    (since the sound speed is zero in the absence of pressure) and have a degenerate structure in which delta is lower than the sound speed of the pure gas phase, and can be substantially lower at high dust densities" (though in some contexts it could represent liquid droplets) and the mixture as a "dusty gas". Dusty gas

  7. SIAM J. SCI. COMPUT. c 2006 Society for Industrial and Applied Mathematics Vol. 28, No. 4, pp. 13351360

    E-Print Network [OSTI]

    LeVeque, Randy

    are nonstrictly hyperbolic (since the sound speed is zero in the absence of pressure) and have a degenerate of sound in the dusty gas is lower than the sound speed of the pure gas phase and can be substantially to the particulate phase as "dust" (though in some contexts it could represent liquid droplets) and to the mixture

  8. Transversal plasma resonance in a nonmagnetized plasma and possibilities of practical employment of it

    E-Print Network [OSTI]

    F. F. Mende

    2005-06-09T23:59:59.000Z

    It is shown that in a nonmagnetized plasma, beside the longitudinal Langmuir resonance, there may also exist the transversal resonance. Both these resonance kinds are degenerated. Employment of the transversal resonance makes it possible to design resonators and filters, as well as powerful single-frequency lasers operating on the basis of collective oscillations of plasma.

  9. Neutral Color Superconductivity and Pseudo-Goldstone Modes

    E-Print Network [OSTI]

    Lianyi He; Meng Jin; Pengfei Zhuang

    2005-05-09T23:59:59.000Z

    Four of the five expected Goldstone modes, which will be eaten up by gauge fields, in neutral two-flavor color superconductor are actually pseudo-Goldstone modes, and their degenerated mass is exactly the magnitude of the color chemical potential, which is introduced to guarantee the color neutrality at moderate baryon density.

  10. Wan Yusof Wan "Frequency modulation spectroscopy for frequency stabilization of dye

    E-Print Network [OSTI]

    .D. thesis 1999 Dallin S. Durfee "Dynamic Properties of Dilute Bose-Einstein Condensates", Ph.D. thesis Dan M Hadzibabic "Studies of a quantum degenerate fermionic lithium gas", Ph.D. thesis Aaron E. Leanhardt", Diploma thesis, University of Heidelberg, Germany 2005 Claudiu Stan "Experiments with Interacting Bose

  11. VOLUME 77, NUMBER 3 P H Y S I C A L R E V I E W L E T T E R S 15 JULY 1996 Bose-Einstein Condensation in a Tightly Confining dc Magnetic Trap

    E-Print Network [OSTI]

    -statistical nature of the BEC transition is com- plicated by strong interactions [3]. BEC was recently created vapors at JILA and MIT [6,7]. A third group, at Rice University, reported cooling of lithium atoms in the study of quantum- degenerate gases [9]. In this Letter, we report a detailed study of the properties

  12. COMMUNICATIONS IN COMPUTATIONAL PHYSICS Vol. 6, No. 1, pp. 49-71

    E-Print Network [OSTI]

    for the mass and momentum, with Darcy's drag as an additional source term in momentum for flows through GDL, and a discontinuous and degenerate convection- diffusion equation for water concentration. Based on the mixed finite element method for the modified Navier-Stokes equation and standard finite element method for wa- ter

  13. Discontinuous Galerkin approximation of two-phase flows in heterogeneous porous media with discontinuous

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , 25]. The governing equations generally consist of an elliptic Darcy-type equation for the pressure to cope with degeneracies in the saturation equation and with media het- erogeneities. The proposed method and a nonlinear degenerate parabolic equation with a nonlinear advective term for the saturation. The dependent

  14. EINDHOVEN UNIVERSITY OF TECHNOLOGY Department of Mathematics and Computer Science

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    in [0,1]. Equation (1.1) results by coupling the mass conservation equations and Darcy laws-01 January 2010 Travelling wave solutions for degenerate pseudo-parabolic equation modelling two-phase flow pseudo-parabolic equation modelling two-phase flow in porous media C.J.van Duijn, Y.Fan, L.A.Peletier, I

  15. DARCY'S FLOW WITH PRESCRIBED CONTACT ANGLE WELL-POSEDNESS AND LUBRICATION APPROXIMATION

    E-Print Network [OSTI]

    DARCY'S FLOW WITH PRESCRIBED CONTACT ANGLE ­ WELL-POSEDNESS AND LUBRICATION APPROXIMATION HANS KN on a solid sub- strate. We use a model for viscous fluids where evolution is governed by Darcy's Law converge to the solutions of a one-dimensional degenerate parabolic fourth order equation which belongs

  16. WELL-POSEDNESS AND UNIFORM BOUNDS FOR A NONLOCAL THIRD ORDER EVOLUTION OPERATOR ON AN

    E-Print Network [OSTI]

    governed by Darcy's Law. After linearization, we obtain a nonlocal third order operator which contains for this linear evolution equation. In the limit of vanishing opening angle, we show the convergence of solutions to a fourth order degenerate parabolic operator, related to the thin-film equation. In the course

  17. A ROBUST FINITE ELEMENT METHOD FOR DARCY--STOKES FLOW

    E-Print Network [OSTI]

    Winther, Ragnar

    . When # = 0 the first equation in (1.1) has the form of Darcy's law for flow in a homogeneous porousA ROBUST FINITE ELEMENT METHOD FOR DARCY--STOKES FLOW KENT ANDRE MARDAL, XUE--CHENG TAI, AND RAGNAR the perturbation parameter is large, while it degenerates to a mixed formulation of Poisson's equation

  18. NUMERICAL SOLUTION OF RESERVOIR FLOW MODELS BASED ON LARGE TIME STEP OPERATOR SPLITTING ALGORITHMS

    E-Print Network [OSTI]

    processes. A black-oil model is commonly used to describe water injection. This model works well. Special focus is posed on the numerical solution algorithms for the saturation equation, which is a convection dominated, degenerate convection-di#11;usion equation. Both theory and applications are discussed

  19. arXiv:astroph/0011099 Mon. Not. R. Astron. Soc. 000, 000{000 (0000) Printed 7 November 2000 (MN L A T E X style le v1.4)

    E-Print Network [OSTI]

    Ramsay, Gavin

    January; in original form 7 November 2000 ABSTRACT Using the Rossi X-ray Timing Explorer and the Nordic into the system, which is most likely evolved, par- tially degenerate and hydrogen depleted (Nelson, Rap- paport contribution from each of two components (point-like blackbody and more spatially extended cut-o#11; power law

  20. Thermoelectric power factor enhancement by ionized nanoparticle scattering Je-Hyeong Bahk,1,a)

    E-Print Network [OSTI]

    Thermoelectric power factor enhancement by ionized nanoparticle scattering Je-Hyeong Bahk,1,a theoretically that the thermoelectric power factor can be enhanced in degenerate semiconductors when embedded intact. We find that the thermoelectric power factor of In0.53Ga0.47As from 300 K to 800 K is enhanced

  1. Uniqueness Theorem for Stationary Axisymmetric Black Holes in Einstein-Maxwell-axion-dilaton Gravity

    E-Print Network [OSTI]

    Marek Rogatko

    2010-07-26T23:59:59.000Z

    We prove the uniqueness theorem for stationary axisymmetric black hole solution in Einstein-Maxwell-axion-dilaton gravity being the low-energy limit of the heterotic string theory. We consider both non-degenerate and extremal Kerr-Sen black hole solutions.

  2. 0306-4549(94)E0007-Z Ann. Nucl. Energy.Vol. 21, No. 7, pp. 433-439, 1994

    E-Print Network [OSTI]

    Pázsit, Imre

    -backward model in criticality calculations), the observation of * Permanent address: Chemical and Nuclear SLAB CRITICALITY EIGENVALUE LIMITS IN A DISCRETE ANGLE MODEL ANIL K. PRINJA* and IMRE PAZSIT Department- pling between 121 and 122 the critical eigenvalue condition is shown to degenerate

  3. Critical fields in ferromagnetic thin films: Identification of four regimes

    E-Print Network [OSTI]

    Otto, Felix

    Critical fields in ferromagnetic thin films: Identification of four regimes Rub´en Cantero­film elements is a paradigm for a multi­scale pattern­forming system. On one hand, there is a material length functional ceases to be positive definite. The degenerate subspace consists of the "unstable modes

  4. "The world's troubles are your troubles. . . and there is nothing wrong with the world that better humans cannot fix."

    E-Print Network [OSTI]

    Lotko, William

    ' revolution similar toTunisia and Egypt are not bright. There are no easy solutions,nor will outside pressure"union" with Russia,buttressed by its energy and financial subsidies,relationships with theWest further degenerated. A few years ago,Lukashenko began having public differences with Russia over the price of energy sold

  5. A low power, high dynamic-range, broadband variable gain amplifier for an ultra wideband receiver

    E-Print Network [OSTI]

    Chen, Lin

    2007-09-17T23:59:59.000Z

    gain steps. The gain control scheme includes fine tuning (2dB/step) by changing the bias voltage of the proposed programmable current mirror, and coarse tuning (14dB/step) by switching on/off the source degeneration resistors in the differential pairs...

  6. Symmetry Breaking in the Zero-Energy Landau Level in Bilayer Graphene P. Cadden-Zimansky,1,2

    E-Print Network [OSTI]

    Kim, Philip

    Symmetry Breaking in the Zero-Energy Landau Level in Bilayer Graphene Y. Zhao,1 P. Cadden, the eightfold degeneracy in the zero-energy Landau level is completely lifted, exhibiting new quantum Hall precisely at the particle-hole degenerate zero en- ergy. While the energy spacing of SLG LLs scales

  7. When Stars Blow Up What Stars Explode?

    E-Print Network [OSTI]

    Walter, Frederick M.

    #12;GK Per = Nova Per 1901 #12;Novae Thermonuclear detonations on a white dwarf ·Hydrogen accumulates the temperature reaches a few MK, fusion begins ·Degenerate fusion is a runaway. ·All the H fuses to He

  8. LETTER doi:10.1038/nature12186 Hofstadter's butterfly and the fractal quantum Hall

    E-Print Network [OSTI]

    Shepard, Kenneth

    Electrons moving through a spatially periodic lattice potential develop a quantized energy spectrum a quantized energy spectrum, consisting of highly degenerate Landau energy levels. When subject to both emergent behaviour within a fractal energy landscape in a system with tunable internal degrees of freedom

  9. Neutrinoless double beta decay

    E-Print Network [OSTI]

    Petr Vogel

    2006-11-17T23:59:59.000Z

    The status of the search for neutrinoless double beta decay is reviewed. The effort to reach the sensitivity needed to cover the effective Majorana neutrino mass corresponding to the degenerate and inverted mass hierarchy is described. Various issues concerning the theory (and phenomenology) of the relation between the $0\

  10. Quasiparticle random phase approximation uncertainties and their correlations in the analysis of neutrinoless double beta decay

    E-Print Network [OSTI]

    Amand Faessler; G. L. Fogli; E. Lisi; V. Rodin; A. M. Rotunno; F. Simkovic

    2009-03-06T23:59:59.000Z

    The variances and covariances associated to the nuclear matrix elements (NME) of neutrinoless double beta decay are estimated within the quasiparticle random phase approximation (QRPA). It is shown that correlated NME uncertainties play an important role in the comparison of neutrinoless double beta decay rates for different nuclei, and that they are degenerate with the uncertainty in the reconstructed Majorana neutrino mass.

  11. Allene and pentatetraene cations as models for intramolecular charge transfer: Vibronic coupling Hamiltonian and conical intersections

    E-Print Network [OSTI]

    Markmann, Andreas

    and pentatetraene. Our aim is to simulate dynamically the charge transfer process when one component is artificiallyAllene and pentatetraene cations as models for intramolecular charge transfer: Vibronic coupling online 13 April 2005 We consider the vibronic coupling effects involving cationic states with degenerate

  12. ELEC 576 Semiconductor Theory for Device Applications Instructor: Dr. D.L. Pulfrey, Room K4040, pulfrey@ece.ubc.ca

    E-Print Network [OSTI]

    Pulfrey, David L.

    ELEC 576 Semiconductor Theory for Device Applications Fall 2005 Instructor: Dr. D.L. Pulfrey, Room the understanding of modern electronic semiconductor devices and the invention or development of new devices. Topics. Semiconductor statistics; low temperatures, degenerate. 4. Tunneling; heterostructures, S-D limitation to MOS

  13. Stellar Burning Falk Herwig, Alexander Heger, and Frank

    E-Print Network [OSTI]

    Herwig, Falk

    ]. In these objects, a thermonuclear runaway of the helium shell on top of an electron-degenerate core (a young White implications for the production of neutron- rich elements. log Tlog Teffeff Figure 1-- A thermonuclear runaway stellar conditions. We will include a stellar equation of state as well as thermonuclear burning (TN burn

  14. NEWS & VIEWS nature physics | VOL 2 | AUGUST 2006 | www.nature.com/naturephysics 505

    E-Print Network [OSTI]

    Loss, Daniel

    TURBULENCE From tea kettlestoexploding stars Turbulent flows, such as those generating the thermonuclear. In thermonuclear supernovae, Rayleigh­Taylor instabilities lead to explosive burning. The reason is that matter in degenerate stars evolving into thermonuclear supernovae expands only very little despite the dramatic

  15. Detecting non-relativistic cosmic neutrinos by capture on tritium: phenomenology and physics potential

    E-Print Network [OSTI]

    Andrew J. Long; Cecilia Lunardini; Eray Sabancilar

    2014-11-12T23:59:59.000Z

    We study the physics potential of the detection of the Cosmic Neutrino Background via neutrino capture on tritium, taking the proposed PTOLEMY experiment as a case study. With the projected energy resolution of $\\Delta \\sim$ 0.15 eV, the experiment will be sensitive to neutrino masses with degenerate spectrum, $m_1 \\simeq m_2 \\simeq m_3 = m_\

  16. Thirteen pump-probe resonances of the sodium D1 line Vincent Wong,* Robert W. Boyd, C. R. Stroud, Jr., Ryan S. Bennink, and Alberto M. Marino

    E-Print Network [OSTI]

    Stroud, Carlos R.

    four-wave mixing in a three-level V system, electromagnetically induced transparency and optical. A Burleigh WA4500 wavemeter monitors the wavelengths of the fields. The pump and probe fi-degenerate four-wave mixing and saturation in a two-level system, difference-frequency crossing and nondegenerate

  17. 15 December 1998 Z .Optics Communications 158 1998 273286

    E-Print Network [OSTI]

    Shahriar, Selim

    system yields strong suppression of quantum phase noise when the probe and conjugate beams are monitored states of the electromagnetic field where the shot noise resulting .from the Heisenberg uncertainty of squeezed states and twin beams via non-degenerate four-wave mixing in a L system M.S. Shahriar a,) , P

  18. Finite element analysis of a current density -electric eld formulation of Bean's model for superconductivity

    E-Print Network [OSTI]

    Styles, Vanessa

    Finite element analysis of a current density - electric #12;eld formulation of Bean's model a current density-electric #12;eld formulation of Bean's model for the experimental set-up of a in#12;nitely. As observed by Bossavit, [4], Bean's critical state model can be formulated as a degenerate Stefan problem

  19. CONDENSATION IN EJECTA FROM DENSE THERMONUCLEAR SUPERNOVAE. T. Yu1, B. S. Meyer1, A. V. Fedkin2, and L. Grossman2,3, 1Department of Physics and Astronomy, Clemson University, Clemson, SC

    E-Print Network [OSTI]

    Grossman, Lawrence

    CONDENSATION IN EJECTA FROM DENSE THERMONUCLEAR SUPERNOVAE. T. Yu1, B. S. Meyer1, A. V. Fedkin2 Thermonuclear Supernova Model: Thermonuclear (Type Ia) supernovae are explosions of white dwarf stars. Our model and then oxy- gen burning proceed under degenerate conditions, a thermonuclear runaway occurs, which leads

  20. Advances in Di#erential Equations, Volume 5 (10--12) October--December 2000, pp. 1465--1492 INTEGRABILITY AND BOUNDEDNESS OF LOCAL

    E-Print Network [OSTI]

    O'Leary, Michael

    --1492 INTEGRABILITY AND BOUNDEDNESS OF LOCAL SOLUTIONS TO DOUBLY DEGENERATE QUASILINEAR PARABOLIC EQUATIONS Mike O'Leary. 1465 #12; 1466 mike o'leary H3) |a(x, t, u, v)| # C 1 {#(|u|)|v| p } 1- 1 p + C 4 |u| #(1- 1 p ) + # 1

  1. Coherent spinor dynamics in a spin-1 Bose condensate

    E-Print Network [OSTI]

    Loss, Daniel

    , for example, a Bose­Einstein condensate or a degenerate Fermi gas, the phase space accessible to low of coherent spin-changing collisions in a gas of spin-1 bosons. Starting with condensates occupying two spin of the gas, although it does not change the nature of the coherence of the condensate--indeed it has been

  2. PUBLISHED ONLINE: 2 NOVEMBER 2014 | DOI: 10.1038/NPHYS3135 Collisions of matter-wave solitons

    E-Print Network [OSTI]

    Loss, Daniel

    we explore the nature of soliton collisions using Bose­Einstein condensates of atoms with attractive of the nonlinear interaction. Our methods for producing a degenerate gas of 7 Li atoms have been described previously14 and are given in the Methods section. A Bose­Einstein condensate of atoms in the |F =1,mF =1

  3. April 200224 ISSN:1369 7021 Elsevier Science Ltd 2002 Conventional superconductors

    E-Print Network [OSTI]

    Davis, James C.

    in the degenerate electron gas of a metal result in the formation of Cooper-pairs1. Each Cooper-pair can tunneling microscopy studies of the atomic-scale effects of individual Ni and Zn impurity atoms superconductivity in the cuprates. STM: constant-current imaging and tunneling spectroscopy We study the electronic

  4. THE CURVE OF "PRYM CANONICAL" GAUSS DIVISORS ON A PRYM THETA DIVISOR

    E-Print Network [OSTI]

    Smith, Roy

    THE CURVE OF "PRYM CANONICAL" GAUSS DIVISORS ON A PRYM THETA DIVISOR Roy Smith and Robert Varley variety (A, ) requires a knowledge of properties of its canonical linear system, the Gauss linear system of the branch divisor of the associated Gauss map on , is not a hypersurface as expected but a non degenerate

  5. Combinatorial cohomology of the space of long knots Arnaud Mortier

    E-Print Network [OSTI]

    Boyer, Edmond

    are endowed with explicit co-orientations, that are canonical in some sense. The combinatorial tools involved in the space of knots, provided that these discs are correctly oriented. This property canonically defines a co-orientation of simple strata. Simple strata are represented by means of degenerated Gauss diagrams, i.e., whose arrows

  6. fur Mathematik in den Naturwissenschaften

    E-Print Network [OSTI]

    Automorphic Forms by Guy Buss Preprint no.: 72 2009 #12;#12;FAMILIES OF LINE BUNDLES OVER RIEMANN SURFACES, THEIR SECTIONS, AND THEIR DEGENERATIONS ­ A CONSTRUCTIVE APPROACH USING AUTOMORPHIC FORMS GUY BUSS Abstract: December 9, 2009. 1 #12;2 GUY BUSS 6.1. Fibre Spaces over Augmented Teichm¨uller Space 53 6.2. Continuous

  7. Search for variation of fundamental constants: Strong enhancements in $X^2\\Pi$ cations of dihalogens and hydrogen halides

    E-Print Network [OSTI]

    Pasteka, L F; Flambaum, V V; Schwerdtfeger, P

    2015-01-01T23:59:59.000Z

    We propose to use diatomic molecular ions to search for strongly enhanced effects of variation of fundamental constants. The relative enhancement occurs in transitions between nearly degenerate levels of different nature. Since the trapping techniques for molecular ions have already been developed, the molecules HBr$^+$, HI$^+$, Br$^+_2$, I$^+_2$, IBr$^+$, ICl$^+$, and IF$^+$ are very promising candidates for such future studies.

  8. TRANSITION TEMPERATURE IN QCD WITH PHYSICAL LIGHT AND STRANGE QUARK MASSES.

    SciTech Connect (OSTI)

    KARSCH, F.

    2006-11-14T23:59:59.000Z

    We present results from a calculation of the transition temperature in QCD with two light (up, down) and one heavier (strange) quark mass as well as for QCD with three degenerate quark masses. Furthermore, we discuss first results from an ongoing calculation of the QCD equation of state with almost realistic light and strange quark masses.

  9. Adenoviral Mediated Gene Delivery to Human Umbilical Cord Mesenchymal Stromal Cells for Inner Ear Hair Cell Differentiation

    E-Print Network [OSTI]

    Devarajan, Keerthana

    2011-07-28T23:59:59.000Z

    . Sensory neural hearing loss (SNHL) is the most common form, which results from degeneration of inner ear sensory hair cells and auditory neurons in the cochlea. In recent years, there has been an increasing interest in gene delivery to mesenchymal stem...

  10. Mixing of the fully symmetric vibrational modes in carbon nanotubes M. Mohr,* M. Machn, and C. Thomsen

    E-Print Network [OSTI]

    Nabben, Reinhard

    Belgrade, Serbia Received 31 October 2006; revised manuscript received 21 February 2007; published 1 May-ph for the radial breathing mode and up to 50 cm-1 difference for the high-energy mode frequency. DOI: 10.1103/Phys measurements are the high-energy modes HEMs around 1600 cm-1 , which correspond to the two doubly degenerated

  11. Beyond Couch Potatoes: From Consumers to Designers Gerhard Fischer

    E-Print Network [OSTI]

    Fischer, Gerhard

    Beyond ÒCouch PotatoesÓ: From Consumers to Designers Gerhard Fischer Center for LifeLong Learning and behavior [44] and contributes to the degeneration of humans into Òcouch potatoes,Ó for whom a remote control is the most important instrument of their cognitive activities. (A Òcouch potatoÓ is a colloquial

  12. THE PROGENITOR OF THE TYPE Ia SUPERNOVA THAT CREATED SNR 0519-69.0 IN THE LARGE MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Edwards, Zachary I. [Department of Earth and Space Sciences, Columbus State University, Columbus, GA 31907 (United States); Pagnotta, Ashley; Schaefer, Bradley E., E-mail: Edwards_Zachary@columbusstate.edu [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States)

    2012-03-10T23:59:59.000Z

    Models for the progenitor systems of Type Ia supernovae can be divided into double-degenerate systems, which contain two white dwarfs, and single-degenerate systems, which contain one white dwarf plus one companion star (either a red giant, a subgiant, or a >1.16 M{sub Sun} main-sequence star). The white dwarf is destroyed in the supernova explosion, but any non-degenerate companion remains intact. We present the results of a search for an ex-companion star in SNR 0519-69.0, located in the Large Magellanic Cloud, based on images taken with the Hubble Space Telescope with a limiting magnitude of V = 26.05. SNR 0519-69.0 is confidently known to be from a Type Ia supernova based on its light echoes and X-ray spectra. The geometric center of the remnant (based on the H{alpha} and X-ray shell) is at 05:19:34.83, -69:02:06.92 (J2000). Accounting for the measurement uncertainties, the orbital velocity, and the kick velocity, any ex-companion star must be within 4.''7 of this position at the 99.73% confidence level. This circle contains 27 main-sequence stars brighter than V = 22.7, any one of which could be the ex-companion star left over from a supersoft source progenitor system. The circle contains no post-main-sequence stars, and this rules out the possibility of all other published single-degenerate progenitor classes (including symbiotic stars, recurrent novae, helium donors, and the spin-up/spin-down models) for this particular supernova. The only remaining possibility is that SNR 0519-69.0 was formed from either a supersoft source or a double-degenerate progenitor system.

  13. Characteristics of the phagocytically-induced respiratory burst in leukocytes from young and aged beagle dogs

    E-Print Network [OSTI]

    Johnson, Denise Donna

    1983-01-01T23:59:59.000Z

    , trichophyton, and mumps, whereas, in other instances no decreases were noted except in elderly persons with acute illness (~Ka , 1979). There is an age- related decline in the proliferative capacity of humans or rodent T-cells t itogens a d tig s (~Ha11 e... key role in the inflammatory response after neutrophils have declined in numbers. It should be noted that both the monocytes and macrophages aid in the acute inflammatory response, but to a lesser degree than do the neutrophils. In chronic...

  14. Aging management guideline for commercial nuclear power plants - heat exchangers

    SciTech Connect (OSTI)

    Booker, S.; Lehnert, D.; Daavettila, N.; Palop, E.

    1994-06-01T23:59:59.000Z

    This Aging Management Guideline (AMG) describes recommended methods for effective detection and mitigation of age-related degradation mechanisms in commercial nuclear power plant heat exchangers important to license renewal. The intent of this AMG is to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR 54. This AMG is presented in a manner that allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  15. Safety research programs sponsored by Office of Nuclear Regulatory Research. Quarterly progress report, October 1-December 31, 1983. Volume 3, No. 4

    SciTech Connect (OSTI)

    Weiss, A J [comp.

    1984-05-01T23:59:59.000Z

    The projects reported are the following: High Temperature Reactor Research, SSC Development, Validation and Application, CRBR Balance of Plant Modeling, Thermal-Hydraulic Reactor Safety Experiments, Development of Plant Analyzer, Code Assessment and Application (Transient and LOCA Analyses), Thermal Reactor Code Development (RAMONA-3B), Calculational Quality Assurance in Support of PTS; Stress Corrosion Cracking of PWR Steam Generator Tubing, Bolting Failure Analysis, Probability Based Load Combinations for Design of Category I Structures, Mechanical Piping Benchmark Problems, Identification of Age-Related Failure Modes; Analysis of Human Error Data for Nuclear Power Plant Safety-Related Events, Human Factors in Nuclear Power Plant Safeguards, Emergency Action Levels, and Protective Action Decision Making.

  16. Health monitoring method for composite materials

    DOE Patents [OSTI]

    Watkins, Jr., Kenneth S. (Dahlonega, GA); Morris, Shelby J. (Hampton, VA)

    2011-04-12T23:59:59.000Z

    An in-situ method for monitoring the health of a composite component utilizes a condition sensor made of electrically conductive particles dispersed in a polymeric matrix. The sensor is bonded or otherwise formed on the matrix surface of the composite material. Age-related shrinkage of the sensor matrix results in a decrease in the resistivity of the condition sensor. Correlation of measured sensor resistivity with data from aged specimens allows indirect determination of mechanical damage and remaining age of the composite component.

  17. Fluctuation properties of laser light after interaction with an atomic system: comparison between two-level and multilevel atomic transitions

    E-Print Network [OSTI]

    Lezama, A; Kastberg, A; Tanzilli, S; Kaiser, R

    2015-01-01T23:59:59.000Z

    The complex internal atomic structure involved in radiative transitions has an effect on the spectrum of fluctuations (noise) of the transmitted light. A degenerate transition has different properties in this respect than a pure two-level transition. We investigate these variations by studying a certain transition between two degenerate atomic levels for different choices of the polarization state of the driving laser. For circular polarization, corresponding to the textbook two-level atom case, the optical spectrum shows the characteristic Mollow triplet for strong laser drive, while the corresponding noise spectrum exhibits squeezing in some frequency ranges. For a linearly polarized drive, corresponding to the case of a multilevel system, additional features appear in both optical and noise spectra. These differences are more pronounced in the regime of a weakly driven transition: whereas the two-level case essentially exhibits elastic scattering, the multilevel case has extra noise terms related to sponta...

  18. Vacuum degeneracy of a circuit-QED system in the ultrastrong coupling regime

    E-Print Network [OSTI]

    Pierre Nataf; Cristiano Ciuti

    2010-01-15T23:59:59.000Z

    We investigate theoretically the quantum vacuum properties of a chain of $N$ superconducting Josephson atoms inductively coupled to a transmission line resonator. We derive the quantum field Hamiltonian for such circuit-QED system, showing that, due to the type and strength of the interaction, a quantum phase transition can occur with a twice degenerate quantum vacuum above a critical coupling. In the finite-size case, the degeneracy is lifted, with an energy splitting decreasing exponentially with increasing values of $g^2 N^2$, where $g$ is the dimensionless vacuum Rabi coupling per artificial atom. We determine analytically the ultrastrong coupling asymptotic expression of the two degenerate vacua for an arbitrary number of artificial atoms and of resonator modes. In the ultrastrong coupling regime the degeneracy is protected with respect to random fluctuations of the transition energies of the Josephson elements.

  19. Speed-up of combustion fronts in shear flows

    E-Print Network [OSTI]

    Hamel, Francois

    2011-01-01T23:59:59.000Z

    This paper is concerned with the analysis of speed-up of reaction-diffusion-advection traveling fronts in infinite cylinders with periodic boundary conditions. The advection is a shear flow with a large amplitude and the reaction is nonnegative, with either positive or zero ignition temperature. The unique or minimal speeds of the traveling fronts are proved to be asymptotically linear in the flow amplitude as the latter goes to infinity, solving an open problem from \\cite{b}. The asymptotic growth rate is characterized explicitly as the unique or minimal speed of traveling fronts for a limiting degenerate problem, and the convergence of the regular traveling fronts to the degenerate ones is proved for positive ignition temperatures under an additional H{\\"{o}}rmander-type condition on the flow.

  20. Metal Alloy Compositions And Process Background Of The Invention

    DOE Patents [OSTI]

    Flemings, Merton C. (Cambridge, MA); Martinez-Ayers, Raul A. (Somerville, MA); de Figueredo, Anacleto M. (Newton, MA); Yurko, James A. (Boston, MA)

    2003-11-11T23:59:59.000Z

    A skinless metal alloy composition free of entrapped gas and comprising primary solid discrete degenerate dendrites homogeneously dispersed within a secondary phase is formed by a process wherein the metal alloy is heated in a vessel to render it a liquid. The liquid is then rapidly cooled while vigorously agitating it under conditions to avoid entrapment of gas while forming solid nuclei homogeneously distributed in the liquid. Agitation then is ceased when the liquid contains a small fraction solid or the liquid-solid alloy is removed from the source of agitation while cooling is continued to form the primary solid discrete degenerate dendrites in liquid secondary phase. The solid-liquid mixture then can be formed such as by casting.

  1. Electron conduction along quantizing magnetic fields in neutron star crusts. II. Practical formulae

    E-Print Network [OSTI]

    A. Y. Potekhin; D. G. Yakovlev

    1997-07-18T23:59:59.000Z

    Practical expressions are derived for a rapid and accurate evaluation of electric and thermal conductivities and thermopower of degenerate relativistic electrons along quantizing magnetic fields in outer neutron star crusts. The electron Coulomb scattering on ions is considered in liquid matter, and on high-temperature phonons or charged impurities in solid matter. A semi-quantitative treatment of low-temperature phonons is also proposed. The transport properties are expressed through the energy dependent effective electron relaxation time, which is calculated using the theoretical formalism of the previous work (astro-ph/9603133). Accurate fitting expressions for the relaxation time are obtained, and an efficient energy averaging procedure proposed. A Fortran code, which calculates the longitudinal transport properties of degenerate electrons in strong magnetic fields for any parameters of dense stellar matter of practical interest, is available from the authors upon request.

  2. Ground state properties of sub-Ohmic spin-boson model with simultaneous diagonal and off-diagonal coupling

    E-Print Network [OSTI]

    Nengji Zhou; Lipeng Chen; Yang Zhao; Dima Mozyrsky; Vladimir Chernyak; Yang Zhao

    2014-11-01T23:59:59.000Z

    By employing the variational approach, density matrix renormalization group (DMRG), exact diagonalization as well as symmetry and mean-field analyses, the ground state properties of the two-bath spin boson model with simultaneous diagonal and off-diagonal coupling are systematically studied in the sub-Ohmic regime. A novel quantum phase transition from a doubly degenerate "localized phase" to the other doubly degenerate "delocalized phase" is uncovered. Via the multi-D1 ansatz as the variational wave function, transition points are determined accurately, consistent with the results from DMRG and exact diagonalization. An effective spatial dimension $d_{eff} = 2.37(6)$ is then estimated, which is found to be compatible with the mean-field prediction. Furthermore, the quantum phase transition is inferred to be of first order for the baths described by a continuous spectral density function. In the case of single mode, however, the transition is softened.

  3. Ab-initio Gorkov-Green's function calculations of open-shell nuclei

    E-Print Network [OSTI]

    V. Soma; C. Barbieri; T. Duguet

    2012-08-13T23:59:59.000Z

    We present results from a new ab-initio method that uses the self-consistent Gorkov Green's function theory to address truly open-shell systems. The formalism has been recently worked out up to second order and is implemented here in nuclei for the first time on the basis of realistic nuclear forces. We find good convergence of the results with respect to the basis size in Ca44 and Ni74 and discuss quantities of experimental interest including ground-state energies, pairing gaps and particle addition/removal spectroscopy. These results demonstrate that the Gorkov method is a valid alternative to multireference approaches for tackling degenerate or near degenerate quantum systems. In particular, it increases the number of mid-mass nuclei accessible in an ab-initio fashion from a few tens to a few hundreds.

  4. A scattering theory for the wave equation on Kerr black hole exteriors

    E-Print Network [OSTI]

    Mihalis Dafermos; Igor Rodnianski; Yakov Shlapentokh-Rothman

    2014-12-29T23:59:59.000Z

    We develop a definitive physical-space scattering theory for the scalar wave equation on Kerr exterior backgrounds in the general subextremal case |a|exterior spacetimes III: the full subextremal case |a|degenerate energy is assumed finite. We show in contrast that the analogous scattering maps cannot be defined for the class of finite non-degenerate energy solutions. This is due to the fact that the celebrated horizon red-shift effect acts as a blue-shift instability when solving the wave equation backwards.

  5. Degeneracy Breaking of Hydrogen Atom

    E-Print Network [OSTI]

    Agung Trisetyarso; Pantur Silaban

    2014-11-21T23:59:59.000Z

    The three dimensional rotation group, SO(3), is a symmetry group of the normal hydrogen atom. Each reducible representation of this group can be associated with a degenerate energy level. If this atom is placed in an external magnetic field, the interaction between the orbital magnetic moment with this field will lead to a symmetry breaking where the symmetry group of the atom is a new group distinct from the SO(3) group. This phenomenon describes the normal Zeeman effect, where a degenerate energy level splits into several new energy levels. It is explicitly shown that each of the new energy levels can be associated with an irreducible representation of the new symmetry group.

  6. Effect of electron flow on the ordinary-extraordinary mode conversion

    SciTech Connect (OSTI)

    Jia Guozhang [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Gao Zhe [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China) and Center for Magnetic Fusion Theory, Chinese Academy of Sciences, Hefei 230031 (China)

    2011-10-15T23:59:59.000Z

    Ordinary-extraordinary mode conversion in the electron cyclotron frequency range is revisited in the presence of a flowing electron component. The analytical expressions of optimal parallel refraction index and conversion efficiency are obtained from a one-dimensional cold plasma model. The presence of flowing electrons leads to an outward shift of the conversion layer and therefore increases the optimal value of parallel refraction index. If this effect is not considered, the efficiency of mode conversion degenerates. In typical tokamak plasmas, this degeneration is about a few percentages, which may induce the reflection of several tens of kilowatts of power from the cutoff layer when injecting megawatts of ECRF power into fusion plasma.

  7. Investigating texture six zero lepton mass matrices

    E-Print Network [OSTI]

    Mahajan, Neelu; Gupta, Manmohan; Gill, P S

    2013-01-01T23:59:59.000Z

    All possible hermitian texture 6 zero Fritzsch like as well as non Fritzsch like lepton mass matrices (144 combinations in all) have been investigated for both Majorana and Dirac neutrinos for their compatibility with the current neutrino oscillation data, keeping in mind the hierarchy of neutrino masses. All the combinations considered here are ruled out by the existing data in the case of inverted hierarchy and degenerate scenario of Majorana neutrino masses. For Majorana neutrinos with normal hierarchy, we find that out of 144 combinations, only 16 possibilities can accommodate the experimental data. Assuming neutrinos to be Dirac particles, normal hierarchy, inverted hierarchy as well as degenerate neutrinos are ruled out for all the combinations.

  8. Adiabatic approximation, Gell-Mann and Low theorem and degeneracies: A pedagogical example

    E-Print Network [OSTI]

    Christian Brouder; Gabriel Stoltz; Gianluca Panati

    2008-07-26T23:59:59.000Z

    We study a simple system described by a 2x2 Hamiltonian and the evolution of the quantum states under the influence of a perturbation. More precisely, when the initial Hamiltonian is not degenerate,we check analytically the validity of the adiabatic approximation and verify that, even if the evolution operator has no limit for adiabatic switchings, the Gell-Mann and Low formula allows to follow the evolution of eigenstates. In the degenerate case, for generic initial eigenstates, the adiabatic approximation (obtained by two different limiting procedures) is either useless or wrong, and the Gell-Mann and Low formula does not hold. We show how to select initial states in order to avoid such failures.

  9. The Majorana Project: A Next-Generation Double-Beta Decay Experiment

    SciTech Connect (OSTI)

    Gehman, Victor M. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); University of Washington, Seattle, WA 98195 (United States)

    2006-07-11T23:59:59.000Z

    The Majorana Project will endeavor to provide direct limits on the effective Majorana mass of the electron neutrino through the measurement of 0{nu}{beta}{beta} decay in 76Ge. Our goal is an experiment with a scalable sensitivity starting at 100 meV (corresponding to the quasi-degenerate mass scale) and ultimately extending well below that level. The current Majorana design consists of several modules, each a close-packed array of 57 Ge detectors, enriched to 86% in 76Ge, in a single cryostat. The ultimate background goal for Majorana is of order one count per tonne of Ge per year in the four keV region of interest around Q{beta}{beta}. This background will allow us to reach an effective Majorana-neutrino mass sensitivity approximately five times better than current results and should cover the quasi-degenerate mass scale.

  10. Self-similar expansion of a warm dense plasma

    SciTech Connect (OSTI)

    Djebli, Mourad [USTHB, Faculty of Physics, Theoretical Physics Laboratory, B.P. 32 Bab-Ezzouar, 16079 Algiers (Algeria)] [USTHB, Faculty of Physics, Theoretical Physics Laboratory, B.P. 32 Bab-Ezzouar, 16079 Algiers (Algeria); Moslem, Waleed M. [Department of Physics, Faculty of Science, Port Said University, Port Said (Egypt)] [Department of Physics, Faculty of Science, Port Said University, Port Said (Egypt)

    2013-07-15T23:59:59.000Z

    The properties of an expanding plasma composed of degenerate electron fluid and non-degenerate ions are studied. For our purposes, we use fluid equations for ions together with the electron momentum equation that include quantum forces (e.g., the quantum statistical pressure, forces due to the electron-exchange and electron correlations effects) and the quasi-neutrality condition. The governing equation is written in a tractable form by using a self-similar transformation. Numerical results for typical beryllium plasma parameters revealed that, during the expansion, the ion acoustic speed decreases for both isothermal and adiabatic ion pressure. When compared with classical hydrodynamic plasma expansion model, the electrons and ions are found to initially escape faster in vacuum creating thus an intense electric field that accelerates most of the particles into the vacuum ahead of the plasma expansion. The relevancy of the present model to beryllium plasma produced by a femto-second laser is highlighted.

  11. Multiple-channel generalization of Lellouch-Lüscher formula: Lattice 2012 conference proceedings

    E-Print Network [OSTI]

    Maxwell T. Hansen; Stephen R. Sharpe

    2012-11-02T23:59:59.000Z

    We describe a generalization of the Lellouch-L\\"uscher formula to the case of multiple strongly-coupled decay channels. As in the original formula, our final result is a relation between weak matrix elements in finite and infinite volumes. Our extension is limited to final states with two scalar particles, with center of mass energies below the lowest three- or four-particle threshold. Otherwise the extension is general, accommodating any number of channels, arbitrary strong coupling between channels, as well as any form of weak decay operators in the matrix elements. Among many possible applications, we emphasize that this is a necessary first step on the way to a lattice-QCD calculation of weak decay rates for D -> pi pi and D -> K K-bar. Our results allow for arbitrary total momentum and hold for degenerate or non-degenerate particles.

  12. Strong Ultraviolet Pulse From a Newborn Type Ia Supernova

    E-Print Network [OSTI]

    Cao, Yi; Howell, D Andrew; Gal-Yam, Avishay; Kasliwal, Mansi M; Valenti, Stefano; Johansson, J; Amanullah, R; Goobar, A; Sollerman, J; Taddia, F; Horesh, Assaf; Sagiv, Ilan; Cenko, S Bradley; Nugent, Peter E; Arcavi, Iair; Surace, Jason; Wo?niak, P R; Moody, Daniela I; Rebbapragada, Umaa D; Bue, Brian D; Gehrels, Neil

    2015-01-01T23:59:59.000Z

    Type Ia supernovae are destructive explosions of carbon oxygen white dwarfs. Although they are used empirically to measure cosmological distances, the nature of their progenitors remains mysterious, One of the leading progenitor models, called the single degenerate channel, hypothesizes that a white dwarf accretes matter from a companion star and the resulting increase in its central pressure and temperature ignites thermonuclear explosion. Here we report observations of strong but declining ultraviolet emission from a Type Ia supernova within four days of its explosion. This emission is consistent with theoretical expectations of collision between material ejected by the supernova and a companion star, and therefore provides evidence that some Type Ia supernovae arise from the single degenerate channel.

  13. Predicting the amount of hydrogen stripped by the SN explosion for SN 2002cx-like SNe Ia

    SciTech Connect (OSTI)

    Liu, Zheng-Wei; Chen, X. F.; Wang, B.; Han, Z. W. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Kromer, M. [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany); Fink, M.; Röpke, F. K. [Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Am Hubland, D-97074 Würzburg (Germany); Pakmor, R., E-mail: zwliu@ynao.ac.cn [Heidelberger Institut für Theoretische Studien, Schloss-Wolfsbrunnenweg 35, D-69118 Heidelberg (Germany)

    2013-12-01T23:59:59.000Z

    The most favored progenitor scenarios for Type Ia supernovae (SNe Ia) involve the single-degenerate (SD) scenario and the double-degenerate scenario. The absence of stripped hydrogen (H) in the nebular spectra of SNe Ia challenges the SD progenitor models. Recently, it was shown that pure deflagration explosion models of Chandrasekhar-mass white dwarfs, ignited off-center, reproduce the characteristic observational features of 2002cx-like SNe Ia very well. In this work we predict, for the first time, the amount of stripped H for the off-center, pure deflagration explosions. We find that their low kinetic energies lead to inefficient H mass stripping (? 0.01 M {sub ?}), indicating that the stripped H may be hidden in (observed) late-time spectra of SN 2002cx-like SNe Ia.

  14. Structures of Human Pumilio with Noncognate RNAs Reveal Molecular Mechanisms for Binding Promiscuity

    SciTech Connect (OSTI)

    Gupta,Y.; Nair, D.; Wharton, R.; Aggarwal, A.

    2008-01-01T23:59:59.000Z

    Pumilio is a founder member of the evolutionarily conserved Puf family of RNA-binding proteins that control a number of physiological processes in eukaryotes. A structure of human Pumilio (hPum) Puf domain bound to a Drosophila regulatory sequence showed that each Puf repeat recognizes a single nucleotide. Puf domains in general bind promiscuously to a large set of degenerate sequences, but the structural basis for this promiscuity has been unclear. Here, we describe the structures of hPum Puf domain complexed to two noncognate RNAs, CycBreverse and Puf5. In each complex, one of the nucleotides is ejected from the binding surface, in effect, acting as a 'spacer.' The complexes also reveal the plasticity of several Puf repeats, which recognize noncanonical nucleotides. Together, these complexes provide a molecular basis for recognition of degenerate binding sites, which significantly increases the number of mRNAs targeted for regulation by Puf proteins in vivo.

  15. A HIGH-RESOLUTION SPECTROSCOPIC SEARCH FOR THE REMAINING DONOR FOR TYCHO'S SUPERNOVA

    SciTech Connect (OSTI)

    Kerzendorf, Wolfgang E.; Yong, David; Schmidt, Brian P.; Murphy, Simon J.; Bessell, Michael S. [Research School of Astronomy and Astrophysics, Mount Stromlo Observatory, Cotter Road, Weston Creek, ACT 2611 (Australia); Simon, Joshua D. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Jeffery, C. Simon [Armagh Observatory, College Hill, Armagh BT61 9DG (United Kingdom); Anderson, Jay [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Podsiadlowski, Philipp [Department of Astrophysics, University of Oxford, Oxford, OX1 3RH (United Kingdom); Gal-Yam, Avishay [Benoziyo Center for Astrophysics, Faculty of Physics, Weizmann Institute of Science, Rehovot 76100 (Israel); Silverman, Jeffrey M.; Filippenko, Alexei V. [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Nomoto, Ken'ichi [Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Venn, Kim A. [Department of Physics and Astronomy, University of Victoria, Elliott Building, 3800 Finnerty Road, Victoria, BC V8P 5C2 (Canada); Foley, Ryan J., E-mail: wkerzend@mso.anu.edu.au [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2013-09-10T23:59:59.000Z

    In this paper, we report on our analysis using Hubble Space Telescope astrometry and Keck-I HIRES spectroscopy of the central six stars of Tycho's supernova remnant (SN 1572). With these data, we measured the proper motions, radial velocities, rotational velocities, and chemical abundances of these objects. Regarding the chemical abundances, we do not confirm the unusually high [Ni/Fe] ratio previously reported for Tycho-G. Rather, we find that for all metrics in all stars, none exhibit the characteristics expected from traditional Type Ia supernova single-degenerate-scenario calculations. The only possible exception is Tycho-B, a rare, metal-poor A-type star; however, we are unable to find a suitable scenario for it. Thus, we suggest that SN 1572 cannot be explained by the standard single-degenerate model.

  16. THE ELM SURVEY. V. MERGING MASSIVE WHITE DWARF BINARIES

    SciTech Connect (OSTI)

    Brown, Warren R.; Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden St, Cambridge, MA 02138 (United States); Kilic, Mukremin; Gianninas, A. [Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, 440 W. Brooks St., Norman, OK, 73019 (United States); Allende Prieto, Carlos, E-mail: wbrown@cfa.harvard.edu, E-mail: skenyon@cfa.harvard.edu, E-mail: kilic@ou.edu, E-mail: alexg@nhn.ou.edu, E-mail: callende@iac.es [Instituto de Astrofisica de Canarias, E-38205, La Laguna, Tenerife (Spain)

    2013-05-20T23:59:59.000Z

    We present the discovery of 17 low-mass white dwarfs (WDs) in short-period (P {<=} 1 day) binaries. Our sample includes four objects with remarkable log g {approx_equal} 5 surface gravities and orbital solutions that require them to be double degenerate binaries. All of the lowest surface gravity WDs have metal lines in their spectra implying long gravitational settling times or ongoing accretion. Notably, six of the WDs in our sample have binary merger times <10 Gyr. Four have {approx}>0.9 M{sub Sun} companions. If the companions are massive WDs, these four binaries will evolve into stable mass transfer AM CVn systems and possibly explode as underluminous supernovae. If the companions are neutron stars, then these may be millisecond pulsar binaries. These discoveries increase the number of detached, double degenerate binaries in the ELM Survey to 54; 31 of these binaries will merge within a Hubble time.

  17. Weak and electromagnetic mechanisms of neutrino-pair photoproduction in a strongly magnetized electron gas

    SciTech Connect (OSTI)

    Borisov, A. V.; Kerimov, B. K.; Sizin, P. E., E-mail: borisov@phys.msu.ru [Moscow State University (Russian Federation)

    2012-11-15T23:59:59.000Z

    Expressions for the power of neutrino radiation from a degenerate electron gas in a strong magnetic field are derived for the case of neutrino-pair photoproduction via the weak and electromagnetic interaction mechanisms (it is assumed that the neutrino possesses electromagnetic form factors). It is shown that the neutrino luminosity of a medium in the electromagnetic reaction channel may exceed substantially the luminosity in the weak channel. Relative upper bounds on the effective neutrino magnetic moment are obtained.

  18. Spectrum of quenched twisted mass lattice QCD at maximal twist

    SciTech Connect (OSTI)

    Abdel-Rehim, Abdou M.; Lewis, Randy; Woloshyn, R.M. [Department of Physics, University of Regina, Regina, SK, S4S 0A2 (Canada); TRIUMF, 4004 Wesbrook Mall, Vancouver, BC, V6T 2A3 (Canada)

    2005-05-01T23:59:59.000Z

    Hadron masses are computed from quenched twisted mass lattice QCD for a degenerate doublet of up and down quarks with the twist angle set to {pi}/2, since this maximally-twisted theory is expected to be free of linear discretization errors. Two separate definitions of the twist angle are used, and the hadron masses for these two cases are compared. The flavor breaking, that can arise due to twisting, is discussed in the context of mass splittings within the {delta}(1232) multiplet.

  19. Lepton Mass Hierarchy and Neutrino Oscillations

    E-Print Network [OSTI]

    H. Fritzsch; Z. Z Xing

    1995-09-26T23:59:59.000Z

    Starting from the symmetry of lepton flavor democracy, we propose and discuss a simple pattern for the mass generation and flavor mixing of the charged leptons and neutrinos. The three neutrino masses are nearly degenerate, and the flavor mixing angles can be calculated. The observed deficit of solar and atmospheric neutrinos can be interpreted as a consequence of the near degeneracy and large oscillations of $\

  20. Landau problem for bilayer graphene: Exact results

    E-Print Network [OSTI]

    Young-Hwan Hyun; Yoonbai Kim; Corneliu Sochichiu; Min-Young Choi

    2010-08-03T23:59:59.000Z

    We consider graphene bilayer in a constant magnetic field of arbitrary orientation (i.e. tilted with respect to the graphene plane). In the low energy approximation to tight binding model with Peierls substitution, we find the exact spectrum of Landau levels. This spectrum is two-fold degenerate in the limit of large in-plane field, which gives rise to a new SU(2) symmetry in this limit.

  1. Spinors, matrix structures, and projective geometry in polarization optics

    E-Print Network [OSTI]

    E. Ovsiyuk; O. Veko; M. Neagu; V. Balan; V. Red'kov

    2014-10-31T23:59:59.000Z

    The paper discusses the role played by Mueller and Jones formalisms in polarization optics, by addressing the following aspects: restriction to the SU(2) symmetry, non-relativistic Stokes 3-vectors; Cartan 2-spinors in polarization optics; Jones 4-spinors for partially polarized light; the linear group SL(4,R) and the classification of 1-parametric Mueller matrices; semi-group structure and classification of degenerate Mueller matrices.

  2. Four-Wave Mixing in Ultracold Atoms using Intermediate Rydberg States

    E-Print Network [OSTI]

    E. Brekke; J. O. Day; T. G. Walker

    2008-08-06T23:59:59.000Z

    Ultracold Rb atoms were used to demonstrate non-degenerate four-wave mixing through a Rydberg state. Continuous 5S-5P-nD two-photon excitation to the Rydberg state was combined with an nD-6P tuned laser in a phase matched geometry. The angular dependence, spatial profile, and dependence on detuning were investigated, showing good agreement with theory. Under optimum conditions 50 percent of the radiation was emitted into the phase-matched direction.

  3. Partial degeneracy effects in the stopping of relativistic electrons in supercompressed thermonuclear fuels

    SciTech Connect (OSTI)

    Starikov, Konstantin V.; Deutsch, Claude [Department of Physics, Kazakh National University, Tole Bi 96, ALMATY 480012 (Kazakhstan) and LPGP (UMR-CNRS 8578), Bat. 210, Universite Paris XI, 91405 Orsay (France)

    2007-02-15T23:59:59.000Z

    The effects of supercompressed and partially degenerate electron fluid on projectile energy loss of laser produced relativistic electron beams (REBs) in the MeV range are investigated. Partial degeneracy is shown to affect significantly the REB stopping power for 0.2{<=}{theta}=T/TF{<=}1 while its variations with beam energy appear much less {theta} dependent. The latter exhibit a characteristic V-like shape for any target electron density, and {theta} values.

  4. Measuring stellar magnetic fields with the low resolution spectropolarimeter of the William Herschel Telescope

    E-Print Network [OSTI]

    F. Leone

    2007-09-13T23:59:59.000Z

    Despite the influence of magnetic fields on the structure and evolution of stars is largely demonstrated from the theoretical point of view, their observational evidence in non-degenerated stars is still rather scanty and mainly circumscribed to bright objects (V 600, show an internal error of <50 G selecting the whole interval and <200 G within a Balmer line. Ripples in the Stokes V spectra of HD3360 result in an instrumental positive magnetic field certainly not larger than 80 G.

  5. Simulating the Haldane Phase in Trapped Ion Spins Using Optical Fields

    E-Print Network [OSTI]

    I. Cohen; P. Richerme; Z. -X. Gong; C. Monroe; A. Retzker

    2015-05-20T23:59:59.000Z

    We propose to experimentally explore the Haldane phase in spin-one XXZ antiferromagnetic chains using trapped ions. We show how to adiabatically prepare the ground states of the Haldane phase, demonstrate their robustness against sources of experimental noise, and propose ways to detect the Haldane ground states based on their excitation gap and exponentially decaying correlations, nonvanishing nonlocal string order, and doubly-degenerate entanglement spectrum.

  6. Electron g-factor Engineering in III-V Semiconductors for Quantum Communications

    E-Print Network [OSTI]

    Hideo Kosaka; Andrey A. Kiselev; Filipp A. Baron; Ki Wook Kim; Eli Yablonovitch

    2001-02-22T23:59:59.000Z

    An entanglement-preserving photo-detector converts photon polarization to electron spin. Up and down spin must respond equally to oppositely polarized photons, creating a requirement for degenerate spin energies, ge=0 for electrons. We present a plot of ge-factor versus lattice constant, analogous to bandgap versus lattice constant, that can be used for g-factor engineering of III-V alloys and quantum wells

  7. A review of "Old Worlds: Egypt, Southwest Asia, India, and Russia in Early Modern English Writing." by John Michael Archer

    E-Print Network [OSTI]

    Galina Yermolenko

    2002-01-01T23:59:59.000Z

    ?s Anthony and Cleopatra. Archer?s reading of Cleopatra as ?Egypt? invokes gender, sexual, and racial stereotypes, but does not show definitively that the play confirms the model of degeneration. The author argues that Egypt was reconstructed in early... Cleopatra as a wonderful piece of work (61) and that early modern English fantasy of Egyptian empire was not altogether unattractive. Hence, the author?s state- ments that Anthony and Cleopatra ?coincides? with the shift in repre- sentation of Egypt...

  8. The World of Dark Shadows Issue 31 

    E-Print Network [OSTI]

    Multiple Contributors

    1982-01-01T23:59:59.000Z

    ; Jensen, 1964, 1965, 1968a, 1968b; Jensen and Fisher, 1967, 1968a; Joshi et al., 1967; Pollock and Jensen, 1964; Reeves and Beasley, 1935; Schultz and Jensen, 1977). Megasporogenesis and megagametogenesis result in formation of an 8-nucleate, 7-celled... is destroyed by entrance of the pollen tube, whereas Jensen and Fisher (1968a) observed one synergid begins to break down at the time of pollination. The degenerating synergid remains in contact with the egg and the central cells during the process...

  9. Two-color ghost interference with photon pairs generated in hot atoms

    SciTech Connect (OSTI)

    Ding Dongsheng; Zhou Zhiyuan; Shi Baosen; Zou Xubo; Guo Guangcan [Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026 (China)

    2012-09-15T23:59:59.000Z

    We report on an experimental observation of a two-photon ghost interference experiment. A distinguishing feature of our experiment is that the photons are generated via a non-degenerated spontaneous four-wave mixing process in a hot atomic ensemble; therefore the photon has narrow bandwidth. Besides, there is a large difference in frequency between two photons in a pair. Our works may be important to achieve more secure, large transmission capacity long-distance quantum communication.

  10. Hydrodynamic equations for electrons in graphene obtained from the maximum entropy principle

    SciTech Connect (OSTI)

    Barletti, Luigi, E-mail: luigi.barletti@unifi.it [Dipartimento di Matematica e Informatica “Ulisse Dini”, Università degli Studi di Firenze, Viale Morgagni 67/A, 50134 Firenze (Italy)

    2014-08-15T23:59:59.000Z

    The maximum entropy principle is applied to the formal derivation of isothermal, Euler-like equations for semiclassical fermions (electrons and holes) in graphene. After proving general mathematical properties of the equations so obtained, their asymptotic form corresponding to significant physical regimes is investigated. In particular, the diffusive regime, the Maxwell-Boltzmann regime (high temperature), the collimation regime and the degenerate gas limit (vanishing temperature) are considered.

  11. Implications of theta_13 on Fritzsch-like lepton mass matrices

    E-Print Network [OSTI]

    Fakay, Priyanka; Verma, Rohit; Ahuja, Gulsheen; Gupta, Manmohan

    2013-01-01T23:59:59.000Z

    Implications of the lepton mixing angles, in particular of theta_13, have been investigated for minimal as well as non-minimal Fritzsch-like textures for the case of Majorana neutrinos. Both, in minimal texture (texture 6 zero lepton mass matrices) and non-minimal textures (two cases of texture 5 zero lepton mass matrices), inverted hierarchy and degenerate scenario of neutrino masses have been ruled out. The implications of theta_13 have been investigated on the lightest neutrino mass m_\

  12. Implications of theta_13 on Fritzsch-like lepton mass matrices

    E-Print Network [OSTI]

    Priyanka Fakay; Samandeep Sharma; Rohit Verma; Gulsheen Ahuja; Manmohan Gupta

    2013-01-25T23:59:59.000Z

    Implications of the lepton mixing angles, in particular of theta_13, have been investigated for minimal as well as non-minimal Fritzsch-like textures for the case of Majorana neutrinos. Both, in minimal texture (texture 6 zero lepton mass matrices) and non-minimal textures (two cases of texture 5 zero lepton mass matrices), inverted hierarchy and degenerate scenario of neutrino masses have been ruled out. The implications of theta_13 have been investigated on the lightest neutrino mass m_\

  13. Low-energy U(1) x USp(2M) gauge theory from simple high-energy gauge group

    E-Print Network [OSTI]

    Sven Bjarke Gudnason; Kenichi Konishi

    2010-05-17T23:59:59.000Z

    We give an explicit example of the embedding of a near BPS low-energy (U(1) x USp(2M))/Z_2 gauge theory into a high-energy theory with a simple gauge group and adjoint matter content. This system possesses degenerate monopoles arising from the high-energy symmetry breaking as well as non-Abelian vortices due to the symmetry breaking at low energies. These solitons of different codimensions are related by the exact homotopy sequences.

  14. Asymptotic results for bifurcations in pure bending of rubber blocks

    E-Print Network [OSTI]

    Coman, Ciprian; 10.1093/qjmam/hbn009

    2008-01-01T23:59:59.000Z

    The bifurcation of an incompressible neo-Hookean thick block with a ratio of thickness to length {eta}, subject to pure bending, is considered. The two incremental equilibrium equations corresponding to a nonlinear pre-buckling state of strain are reduced to a fourth-order linear eigenproblem that displays a multiple turning point. It is found that for 0 {infty} degenerates into a surface instability. Singular perturbation methods enable us to capture this transition, while direct numerical simulations corroborate the analytical results.

  15. Quasiparticle random phase approximation uncertainties and their correlations in the analysis of 0{nu}{beta}{beta} decay

    SciTech Connect (OSTI)

    Faessler, Amand; Rodin, V. [Institute of Theoretical Physics, University of Tuebingen, 72076 Tuebingen (Germany); Fogli, G. L.; Rotunno, A. M. [Dipartimento Interateneo di Fisica 'Michelangelo Merlin', Via Amendola 173, 70126 Bari (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Via Orabona 4, 70126 Bari (Italy); Lisi, E. [Istituto Nazionale di Fisica Nucleare, Sezione di Bari, Via Orabona 4, 70126 Bari (Italy); Simkovic, F. [Institute of Theoretical Physics, University of Tuebingen, 72076 Tuebingen (Germany); Bogoliubov Laboratory of Theoretical Physics, JINR, 141980 Dubna (Russian Federation); Department of Nuclear Physics, Comenius University, Mlynska dolina F1, SK-842 15 Bratislava (Slovakia)

    2009-03-01T23:59:59.000Z

    The variances and covariances associated to the nuclear matrix elements of neutrinoless double beta decay (0{nu}{beta}{beta}) are estimated within the quasiparticle random phase approximation. It is shown that correlated nuclear matrix elements uncertainties play an important role in the comparison of 0{nu}{beta}{beta} decay rates for different nuclei, and that they are degenerate with the uncertainty in the reconstructed Majorana neutrino mass.

  16. Optical vortex interaction and generation via nonlinear wave mixing

    SciTech Connect (OSTI)

    Lenzini, F. [INLN, Universite de Nice-Sophia Antipolis, CNRS, 1361 route des Lucioles, FR-06560 Valbonne (France); Dipartimento di Fisica, Universita di Firenze, via Sansone 1, IT-50019 Sesto Fiorentino (Italy); Residori, S.; Bortolozzo, U. [INLN, Universite de Nice-Sophia Antipolis, CNRS, 1361 route des Lucioles, FR-06560 Valbonne (France); Arecchi, F. T. [Dipartimento di Fisica, Universita di Firenze, via Sansone 1, IT-50019 Sesto Fiorentino (Italy)

    2011-12-15T23:59:59.000Z

    Optical vortex beams are made to interact via degenerate two-wave mixing in a Kerr-like nonlinear medium. Vortex mixing is shown to occur inside the medium, leading to exchange of topological charge and cascaded generation of vortex beams. A mean-field model is developed and is shown to account for the selection rules of the topological charges observed after the wave-mixing process. Fractional charges are demonstrated to follow the same rules as for integer charges.

  17. Beam driven upper-hybrid-wave instability in quantized semiconductor plasmas

    SciTech Connect (OSTI)

    Jamil, M. [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan)] [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Rasheed, A. [Department of Physics, Government College University, Faisalabad 38000 (Pakistan)] [Department of Physics, Government College University, Faisalabad 38000 (Pakistan); Rozina, Ch. [Department of Physics, Government M.A.O. College, Lahore 54000 (Pakistan)] [Department of Physics, Government M.A.O. College, Lahore 54000 (Pakistan); Moslem, W. M. [Department of Physics, Faculty of Science, Port Said University, Port Said 42521 (Egypt) [Department of Physics, Faculty of Science, Port Said University, Port Said 42521 (Egypt); Centre for Theoretical Physics, The British University in Egypt (BUE), El-Shorouk City, Cairo (Egypt); Salimullah, M. [Department of Physics, Jahangirnagar University, Savar, Dhaka 1342 (Bangladesh)] [Department of Physics, Jahangirnagar University, Savar, Dhaka 1342 (Bangladesh)

    2014-02-15T23:59:59.000Z

    The excitation of Upper-Hybrid waves (UHWs) induced by electron beam in semiconductor plasma is examined using quantum hydrodynamic model. Various quantum effects are taken into account including recoil effect, Fermi degenerate pressure, and exchange-correlation potential. The bandwidth of the UHWs spectrum shows that the system supports purely growing unstable mode. The latter has been studied for diversified parameters of nano-sized GaAs semiconductor.

  18. Photon-photon polarization correlations as a tool for studying parity non-conservation in heliumlike Uranium

    E-Print Network [OSTI]

    Filippo Fratini; Sergiy Trotsenko; Stanislav Tashenov; Thomas Stoehlker; Andrey Surzhykov

    2011-03-27T23:59:59.000Z

    Due to electron-nucleus weak interaction, atomic bound states with different parities turn out to be mixed. We discuss a prospect for measuring the mixing parameter between the nearly degenerate metastable states 1s_{1/2} 2s_{1/2} : J = 0 and 1s_{1/2} 2p_{1/2} : J = 0 in heliumlike Uranium. Our analysis is based on the polarization properties of the photons emitted in the two-photon decays of such states.

  19. Gender dependent survival of allogeneic trophoblast stem cells

    E-Print Network [OSTI]

    Epple - Farmer, Jessica Anne

    2009-05-15T23:59:59.000Z

    stem cells may exhibit and confer immune privilege. These findings suggest applications in cell and gene therapy as well as provide a new model for studying trophoblast physiology and immunology. iv DEDICATION John Donne wrote that ?No man... or their in vitro-differentiated derivatives have been largely unsuccessful. When syngeneic TS cells were injected subcutaneously into non-pregnant females, they were reported to differentiate into giant cells within 5-10 days and to degenerate rapidly (7...

  20. Mass Splitting of Staggered Fermion and $SO(2D)$ Clifford Algebra

    E-Print Network [OSTI]

    M. Hatakeyama; H. Sawanaka; H. So

    2006-09-28T23:59:59.000Z

    We present a new method to introduce rotationally invariant terms in staggered fermions which is based on an $SO(2D)$ Clifford algebra formulation, where $D$ means the number of space-time dimensions. We have four candidates for improved mass terms that can split the degenerate mass of staggered fermions. Among them, we analyze three types of combinations and find only one case that can identify with the light single Dirac mode.

  1. Superconductors with Topological Order

    E-Print Network [OSTI]

    M. C. Diamantini; P. Sodano; C. A. Trugenberger

    2005-11-18T23:59:59.000Z

    We propose a mechanism of superconductivity in which the order of the ground state does not arise from the usual Landau mechanism of spontaneous symmetry breaking but is rather of topological origin. The low-energy effective theory is formulated in terms of emerging gauge fields rather than a local order parameter and the ground state is degenerate on topologically non-trivial manifolds. The simplest example of this mechanism of superconductivty is concretely realized as global superconductivty in Josephson junction arrays.

  2. Harmonic oscillator in a background magnetic field in noncommutative quantum phase-space

    E-Print Network [OSTI]

    Joseph Ben Geloun; Sunandan Gangopadhyay; Frederik G Scholtz

    2009-01-22T23:59:59.000Z

    We solve explicitly the two-dimensional harmonic oscillator and the harmonic oscillator in a background magnetic field in noncommutative phase-space without making use of any type of representation. A key observation that we make is that for a specific choice of the noncommutative parameters, the time reversal symmetry of the systems get restored since the energy spectrum becomes degenerate. This is in contrast to the noncommutative configuration space where the time reversal symmetry of the harmonic oscillator is always broken.

  3. Holonomic Quantum Computing Based on the Stark Effect

    E-Print Network [OSTI]

    Bernevig, B A

    2004-01-01T23:59:59.000Z

    We propose a spin manipulation technique based entirely on electric fields applied to acceptor states in $p$-type semiconductors with spin-orbit coupling. While interesting in its own right, the technique can also be used to implement fault-resilient holonomic quantum computing. We explicitly compute adiabatic transformation matrix (holonomy) of the degenerate states and comment on the feasibility of the scheme as an experimental technique.

  4. Holonomic Quantum Computing Based on the Stark Effect

    E-Print Network [OSTI]

    B. A. Bernevig; S. C. Zhang

    2004-02-23T23:59:59.000Z

    We propose a spin manipulation technique based entirely on electric fields applied to acceptor states in $p$-type semiconductors with spin-orbit coupling. While interesting in its own right, the technique can also be used to implement fault-resilient holonomic quantum computing. We explicitly compute adiabatic transformation matrix (holonomy) of the degenerate states and comment on the feasibility of the scheme as an experimental technique.

  5. Exciton Bose condensation : the ground state of an electron-hole gas I. Mean field description of a simplified model

    E-Print Network [OSTI]

    Boyer, Edmond

    1069 Exciton Bose condensation : the ground state of an electron-hole gas I. Mean field description dégénérées. Nous étudions la condensation de Bose de ce système en fonction de la densité, négligeant dans-hole gas in a simple model semiconductor, with direct gap and isotropic, non degenerate bands. We study

  6. On the ultimate fate of AM Her stars

    E-Print Network [OSTI]

    F. Meyer; E. Meyer-Hofmeister

    1999-05-06T23:59:59.000Z

    We suggest, that the magnetic field of the white dwarf in AM Her systems loses coupling to the secondary star when the latter becomes non-magnetic at the transition from a late main sequence star to a cool degenerate brown dwarf. This leads to spin-up of the primary white dwarf. After synchronous rotation is lost the systems do not appear as AM Her stars anymore. We discuss the further evolution of such systems.

  7. Hybrid Monte Carlo with Wilson Dirac operator on the Fermi GPU

    E-Print Network [OSTI]

    Chakrabarty, Abhijit

    2012-01-01T23:59:59.000Z

    In this article we present our implementation of a Hybrid Monte Carlo algorithm for Lattice Gauge Theory using two degenerate flavours of Wilson-Dirac fermions on a Fermi GPU. We find that using registers instead of global memory speeds up the code by almost an order of magnitude. To map the array variables to scalars, so that the compiler puts them in the registers, we use code generators. Our final program is more than 10 times faster than a generic single CPU.

  8. Hybrid Monte Carlo with Wilson Dirac operator on the Fermi GPU

    E-Print Network [OSTI]

    Abhijit Chakrabarty; Pushan Majumdar

    2012-07-10T23:59:59.000Z

    In this article we present our implementation of a Hybrid Monte Carlo algorithm for Lattice Gauge Theory using two degenerate flavours of Wilson-Dirac fermions on a Fermi GPU. We find that using registers instead of global memory speeds up the code by almost an order of magnitude. To map the array variables to scalars, so that the compiler puts them in the registers, we use code generators. Our final program is more than 10 times faster than a generic single CPU.

  9. Comparative dermotoxicity of shale oils

    SciTech Connect (OSTI)

    Holland, L.M.; Wilson, J.S.; Foreman, M.E.

    1980-01-01T23:59:59.000Z

    When shale oils are applied at higher dose levels the standard observation of tumor production and latency are often obscured by a severe inflammatory response leading to epidermal degeneration. The two experiments reported here are still in progress, however the interim results are useful in assessing both the phlogistic and tumorigenic properties of three shale oils. Three shale oils were tested in these experiments. The first crude oil (OCSO No. 6) was produced in a modified in situ report at Occidental Oil Company's Logan Wash site near Debeque, Colorado. The second crude oil (PCSO II) was produced in the above ground Paraho vertical-kiln retort located at Anvil Points near Rifle, Colorado and the third oil was the hydrotreated daughter product of the Paraho crude (PCSO-UP). Experiment I was designed to determine the highest dose level at which tumor latency could be measured without interference from epidermal degeneration. Experiment II was designed to determine the effect of application frequency on both tumor response and inflammatory phenomena. Complete epidermal degeneration was used as the only measure of severe inflammation. Relative tumorigenicity was based on the number of tumor bearing mice without regard to multiple tumors on individual animals. In both experiments, tumor occurrence was confirmed one week after initial appearance. The sex-related difference in inflammatory response is striking and certanly has significance for experimental design. An increased phlogistic sensitivity expressed in male mice could affect the meaning of an experiment where only one sex was used.

  10. Optimal degeneracy for the signal-recycling cavity in advanced LIGO

    E-Print Network [OSTI]

    Yi Pan

    2006-08-29T23:59:59.000Z

    As currently designed, the signal-recycling cavity (SRC) in the Advanced-LIGO interferometer is degenerate. In such a degenerate cavity, the phase fronts of optical fields become badly distorted when the mirror shapes are slightly deformed due to mirror figure error and/or thermal aberration, and this causes significant loss of the signal power and the signal-to-noise ratio (SNR) of a gravitational wave event. Through a numerical modal simulation of the optical fields in a simplified model of an Advanced-LIGO interferometer, We investigate the loss of the SNR and the behavior of both the carrier and signal optical fields, with the SRC at various levels of degeneracy. We show that the loss of the SNR is severe with a degenerate SRC, and a nondegenerate SRC can be used to solve this problem. We identify the optimal level of degeneracy for the SRC, which is achieved when the cavity Gouy phase is between 0.2 and 1.3 radians. We also discuss possible alternative designs of the SRC to achieve this optimal degeneracy.

  11. Kowalevski top in quantum mechanics

    SciTech Connect (OSTI)

    Matsuyama, A., E-mail: spamatu@ipc.shizuoka.ac.jp

    2013-09-15T23:59:59.000Z

    The quantum mechanical Kowalevski top is studied by the direct diagonalization of the Hamiltonian. The spectra show different behaviors depending on the region divided by the bifurcation sets of the classical invariant tori. Some of these spectra are nearly degenerate due to the multiplicity of the invariant tori. The Kowalevski top has several symmetries and symmetry quantum numbers can be assigned to the eigenstates. We have also carried out the semiclassical quantization of the Kowalevski top by the EBK formulation. It is found that the semiclassical spectra are close to the exact values, thus the eigenstates can be also labeled by the integer quantum numbers. The symmetries of the system are shown to have close relations with the semiclassical quantum numbers and the near-degeneracy of the spectra. -- Highlights: •Quantum spectra of the Kowalevski top are calculated. •Semiclassical quantization is carried out by the EBK formulation. •Quantum states are labeled by the semiclassical integer quantum numbers. •Multiplicity of the classical torus makes the spectra nearly degenerate. •Symmetries, quantum numbers and near-degenerate spectra are closely related.

  12. Kinetic and electron-electron energies for convex sums of ground state densities with degeneracies and fractional electron number

    SciTech Connect (OSTI)

    Levy, Mel, E-mail: ayers@mcmaster.ca, E-mail: mlevy@tulane.edu [Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States) [Department of Chemistry, Duke University, Durham, North Carolina 27708 (United States); Department of Physics, North Carolina A and T State University, Greensboro, North Carolina 27411 (United States); Department of Chemistry, Tulane University, New Orleans, Louisiana 70118 (United States); Anderson, James S. M.; Zadeh, Farnaz Heidar; Ayers, Paul W., E-mail: ayers@mcmaster.ca, E-mail: mlevy@tulane.edu [Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario (Canada)

    2014-05-14T23:59:59.000Z

    Properties of exact density functionals provide useful constraints for the development of new approximate functionals. This paper focuses on convex sums of ground-level densities. It is observed that the electronic kinetic energy of a convex sum of degenerate ground-level densities is equal to the convex sum of the kinetic energies of the individual degenerate densities. (The same type of relationship holds also for the electron-electron repulsion energy.) This extends a known property of the Levy-Valone Ensemble Constrained-Search and the Lieb Legendre-Transform refomulations of the Hohenberg-Kohn functional to the individual components of the functional. Moreover, we observe that the kinetic and electron-repulsion results also apply to densities with fractional electron number (even if there are no degeneracies), and we close with an analogous point-wise property involving the external potential. Examples where different degenerate states have different kinetic energy and electron-nuclear attraction energy are given; consequently, individual components of the ground state electronic energy can change abruptly when the molecular geometry changes. These discontinuities are predicted to be ubiquitous at conical intersections, complicating the development of universally applicable density-functional approximations.

  13. The Remarkable Deaths of 9 - 11 Solar Mass Stars

    E-Print Network [OSTI]

    Woosley, S E

    2015-01-01T23:59:59.000Z

    The post-helium burning evolution of stars from 7 to 11 solar masses is complicated by the lingering effects of degeneracy and off-center ignition. Here stars in this mass range are studied using a standard set of stellar physics. Two important aspects of the study are the direct coupling of a reaction network of roughly 220 nuclei to the structure calculation at all stages and the use of a sub grid model to describe the convective bounded flame that develops during neon and oxygen burning. Below 9.0 solar masses, degenerate oxygen-neon cores form that may become either white dwarfs or electron-capture supernovae. Above 10.3 solar masses the evolution proceeds "normally" to iron-core collapse, without composition inversions or degenerate flashes. Emphasis here is upon the stars in between which typically ignite oxygen burning off center. After oxygen burns in a convectively bounded flame, silicon burning ignites in a degenerate flash that commences closer to the stellar center and with increasing violence for...

  14. Generation of polarization entangled photons using type-II doubly periodically poled lithium niobate waveguides

    E-Print Network [OSTI]

    K. Thyagarajan; K. Sinha; J. Lugani; S. Ghosh; A. Martin; D. B. Ostrowsky; O. Alibart; S. Tanzilli

    2009-12-29T23:59:59.000Z

    In this paper, we address the issue of the generation of non-degenerate cross-polarization-entangled photon pairs using type-II periodically poled lithium niobate. We show that, by an appropriate engineering of the quasi-phase-matching grating, it is possible to simultaneously satisfy the conditions for two spontaneous parametric down-conversion processes, namely ordinary pump photon down-conversion to either extraordinary signal and ordinary idler paired photons, or to ordinary signal and extraordinary idler paired photons. In contrast to single type-II phase-matching, these two processes, when enabled together, can lead to the direct production of cross-polarization-entangled state for non degenerate signal and idler wavelengths. Such a scheme should be of great interest in applications requiring polarization-entangled non degenerate paired photons with, for instance, one of the entangled photons at an appropriate wavelength being used for local operation or for quantum storage in an atomic ensemble, and the other one at the typical wavelength of 1550 nm for propagation through an optical fiber.

  15. Outrunning major weight gain: a prospective study of 8,340consistent runners during 7 years of follow-up

    SciTech Connect (OSTI)

    Williams, Paul T.

    2006-01-06T23:59:59.000Z

    Background: Body weight increases with aging. Short-term,longitudinal exercise training studies suggest that increasing exerciseproduces acute weight loss, but it is not clear if the maintenance oflong-term, vigorous exercise attenuates age-related weight gain inproportion to the exercise dose. Methods: Prospective study of 6,119 maleand 2,221 female runners whose running distance changed less than 5 km/wkbetween their baseline and follow-up survey 7 years later. Results: Onaverage, men who ran modest (0-24 km/wk), intermediate (24-48 km/wk) orprolonged distances (>_48 km/wk) all gained weight throughage 64,however, those who ran ?48 km/wk had one-half the average annual weightgain of those who ran<24 km/wk. Age-related weight gain, and itsreduction by running, were both greater in younger than older men. Incontrast, men s gain in waist circumference with age, and its reductionby running, were the same in older and younger men. Women increased theirbody weight and waist and hip circumferences over time, regardless ofage, which was also reduced in proportion to running distance. In bothsexes, running did not attenuate weight gain uniformly, but ratherdisproportionately prevented more extreme increases. Conclusion: Men andwomen who remain vigorously active gain less weight as they age and thereduction is in proportion to the exercise dose.

  16. A Review of Information for Managing Aging in Nuclear Power Plants

    SciTech Connect (OSTI)

    WC Morgan; JV Livingston

    1995-09-01T23:59:59.000Z

    Age related degradation effects in safety related systems of nuclear power plants should be managed to prevent safety margins from eroding below the acceptable limits provided in plant design bases. The Nuclear Plant Aging Research (NPAR) Pro- gram, conducted under the auspices of the U.S. Nuclear Regulatory Commission (NRC), Office of Nuclear Regulatory Research, and other related aging management programs are developing technical information on managing aging. The aging management process central to these efforts consists of three key elements: 1) selecting structures, systems, and components (SSCs) in which aging should be controlled; 2) understanding the mechanisms and rates of degradation in these SSCs; and 3) managing degradation through effective inspection, surveillance, condition monitoring, trending, record keeping, mainten- ance, refurbishment, replacement, and adjustments in the operating environment and service conditions. This document concisely reviews and integrates information developed under the NPAR Program and other aging management studies and other available information related to understanding and managing age-related degradation effects and provides specific refer- ences to more comprehensive information on the same subjects.

  17. Transport of Magnetic Fields in Convective, Accreting Supernova Cores

    E-Print Network [OSTI]

    Christopher Thompson; Norman Murray

    2001-05-24T23:59:59.000Z

    We consider the amplification and transport of a magnetic field in the collapsed core of a massive star, including both the region between the neutrinosphere and the shock, and the central, opaque core. An analytical argument explains why rapid convective overturns persist within a newly formed neutron star for roughly 10 seconds ($> 10^3$ overturns), consistent with recent numerical models. A dynamical balance between turbulent and magnetic stresses within this convective layer corresponds to flux densities in excess of $10^{15}$G. Material accreting onto the core is heated by neutrinos and also becomes strongly convective. We compare the expected magnetic stresses in this convective `gain layer' with those deep inside the neutron core. Buoyant motions of magnetized fluid are greatly aided by the intense neutrino flux. We calculate the transport rate through a medium containing free neutrons protons, and electrons, in the limiting cases of degenerate or non-degenerate nucleons. Fields stronger than $\\sim 10^{13}$ G are able to rise through the outer degenerate layers of the neutron core during the last stages of Kelvin-Helmholtz cooling (up to 10 seconds post-collapse), even though these layers have become stable to convection. We also find the equilibrium shape of a thin magnetic flux rope in the dense hydrostatic atmosphere of the neutron star, along with the critical separation of the footpoints above which the rope undergoes unlimited expansion against gravity. The implications of these results for pulsar magnetism are summarized, and applied to the case of late fallback over the first 1,000-10,000 s of the life of a neutron star

  18. A SEARCH FOR RAPIDLY ACCRETING WHITE DWARFS IN THE SMALL MAGELLANIC CLOUD

    SciTech Connect (OSTI)

    Lepo, Kelly; Van Kerkwijk, Marten, E-mail: lepo@astro.utoronto.ca, E-mail: mhvk@astro.utoronto.ca [Department of Astronomy and Astrophysics, University of Toronto, 50 Saint George St., Toronto, ON M5S 3H4 (Canada)

    2013-07-01T23:59:59.000Z

    The nature of the progenitors of Type Ia supernovae (SNe Ia) is still a mystery. While plausible candidates are known for both the single-degenerate and double-degenerate models, the observed numbers fall significantly short of what is required to reproduce the SNe Ia rate. Some of the most promising single-degenerate Type Ia progenitors are recurrent novae and super-soft sources (SSS). White dwarfs (WDs) with higher mass transfer rates can also be SN Ia progenitors. For these rapidly accreting white dwarfs (RAWDs), more material than is needed for steady burning accretes on the WD, and extends the WD's photosphere. Unlike SSS, such objects will likely not be detectable at soft X-ray energies, but will be bright at longer wavelengths, such as the far-ultraviolet (UV). Possible examples include LMC N66 and the V Sagittae stars. We present a survey using multi-object spectrographs looking for RAWDs in the central core of the Small Magellanic Cloud (SMC), from objects selected to be bright in the far-UV and with blue far UV - V colors. While we find some unusual objects, and recover known planetary nebula and Wolf-Rayet (WR) stars, we detect no candidate RAWD. The upper limits from this non-detection depend on our expectations of what an RAWD should look like, as well assumptions about the internal extinction of the SMC. Assuming they resemble LMC N66 or fainter versions of WR stars we set an upper limit of 10-14 RAWDs in the SMC. However, our survey is unlikely to detect objects like V Sge, and hence we cannot set meaningful upper limits if RAWDs generally resemble V Sge.

  19. A seismic approach to testing different formation channels of subdwarf B stars

    E-Print Network [OSTI]

    Haili Hu; M. -A. Dupret; C. Aerts; G. Nelemans; S. D. Kawaler; A. Miglio; J. Montalban; R. Scuflaire

    2008-08-22T23:59:59.000Z

    There are many unknowns in the formation of subdwarf B stars. Different formation channels are considered to be possible and to lead to a variety of helium-burning subdwarfs. All seismic models to date, however, assume that a subdwarf B star is a post-helium-flash-core surrounded by a thin inert layer of hydrogen. We examine an alternative formation channel, in which the subdwarf B star originates from a massive (>~2 Msun) red giant with a non-degenerate helium-core. Although these subdwarfs may evolve through the same region of the log g-Teff diagram as the canonical post-flash subdwarfs, their interior structure is rather different. We examine how this difference affects their pulsation modes and whether it can be observed. Using detailed stellar evolution calculations we construct subdwarf B models from both formation channels. The iron accumulation in the driving region due to diffusion, which causes the excitation of the modes, is approximated by a Gaussian function. The pulsation modes and frequencies are calculated with a non-adiabatic pulsation code. A detailed comparison of two subdwarf B models from different channels, but with the same log g and Teff, shows that their mode excitation is different. The excited frequencies are lower for the post-flash than for the post-non-degenerate subdwarf B star. This is mainly due to the differing chemical composition of the stellar envelope. A more general comparison between two grids of models shows that the excited frequencies of most post-non-degenerate subdwarfs cannot be well-matched with the frequencies of post-flash subdwarfs. In the rare event that an acceptable seismic match is found, additional information, such as mode identification and log g and Teff determinations, allows us to distinguish between the two formation channels.

  20. A self-injected, diode-pumped, solid-state ring laser for laser cooling of Li atoms

    E-Print Network [OSTI]

    Miake, Yudai; O'Hara, Kenneth M; Gensemer, Stephen

    2015-01-01T23:59:59.000Z

    We have constructed a solid-state light source for experiments with laser cooled lithium atoms based on a Nd:YVO$_4$ ring laser with second-harmonic generation. Unidirectional lasing, an improved mode selection, and a high output power of the ring laser was achieved by weak coupling to an external cavity which contained the lossy elements required for single frequency operation. Continuous frequency tuning is accomplished by controlling two PZTs in the internal and the external cavities simultaneously. The light source has been utilized to trap and cool fermionic lithium atoms into the quantum degenerate regime.