Science.gov

Sample records for anderson quin cycle

  1. Quine's 'needlessly strong' holism.

    PubMed

    Verhaegh, Sander

    2017-02-01

    Quine is routinely perceived as having changed his mind about the scope of the Duhem-Quine thesis, shifting from what has been called an 'extreme holism' to a more moderate view. Where the Quine of 'Two Dogmas of Empiricism' argues that "the unit of empirical significance is the whole of science" (1951, 42), the later Quine seems to back away from this "needlessly strong statement of holism" (1991, 393). In this paper, I show that the received view is incorrect. I distinguish three ways in which Quine's early holism can be said to be wide-scoped and show that he has never changed his mind about any one of these aspects of his early view. Instead, I argue that Quine's apparent change of mind can be explained away as a mere shift of emphasis.

  2. Quine and the Segregrational Sign.

    ERIC Educational Resources Information Center

    Wolf, George

    1999-01-01

    In the context of theory of integrational linguistics, the segregational sign is distinguished from the integrational sign, and the operation of the former is analyzed. Focus is on how logic guides the sign, and how the theory of W. V. Quine accounts for these issues. (MSE)

  3. A note on the use of Quin2 in studying shear-induced platelet aggregation.

    PubMed

    Giorgio, T D; Hellums, J D

    1986-02-01

    Quin2, a calcium ion chelator which can penetrate plasma membranes, was used to study the role of intracellular calcium ion concentration in mediating shear-induced platelet activation. Washed platelet suspensions were subjected to various levels of uniform, known shear stress in a cone and plate viscometer in the absence of added agonists. Additional samples were aggregated in response to chemical platelet agonists in a conventional aggregometer. The aggregometer response of Quin2-containing platelets to collagen, thrombin and ADP exhibited increased lag time and reduced maximum rate of aggregation in comparison to controls. However, the extent of aggregation of the Quin2-containing platelets eventually reached the same level as that of the controls. Very different results were obtained for aggregation by shear stress in the viscometer. Shear-induced aggregation was significantly suppressed by Quin2 treatment at both short (30 seconds) and long (300 seconds) times of exposure to the shear field. Shear-induced dense granular release and cellular lysis were unaltered by Quin2 treatment at 30 second exposure times, but both were significantly increased by Quin2 treatment at 300 second exposure times. These results suggest that intracellular calcium ion mobilization is an important early step in shear-induced platelet activation. Additionally, Quin2 appears to have effects resulting in increased platelet fragility. Thus, the findings raise questions on the suitability of Quin2 as an intracellular calcium ion probe in studies in shear fields.

  4. Anderson during EVA 2

    NASA Image and Video Library

    2010-04-11

    ISS023-E-021558 (11 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, participates in the mission's second session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the seven-hour, 26-minute spacewalk, Anderson and Rick Mastracchio (out of frame), mission specialist, unhooked and removed the depleted ammonia tank and installed a 1,700-pound ammonia tank on the station’s Starboard 1 truss, completing the second of a three-spacewalk coolant tank replacement process.

  5. Anderson during EVA 2

    NASA Image and Video Library

    2010-04-11

    ISS023-E-021561 (11 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, participates in the mission's second session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the seven-hour, 26-minute spacewalk, Anderson and Rick Mastracchio (out of frame), mission specialist, unhooked and removed the depleted ammonia tank and installed a 1,700-pound ammonia tank on the station’s Starboard 1 truss, completing the second of a three-spacewalk coolant tank replacement process.

  6. Anderson during EVA 2

    NASA Image and Video Library

    2010-04-11

    ISS023-E-021562 (11 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, participates in the mission's second session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the seven-hour, 26-minute spacewalk, Anderson and Rick Mastracchio (out of frame), mission specialist, unhooked and removed the depleted ammonia tank and installed a 1,700-pound ammonia tank on the station’s Starboard 1 truss, completing the second of a three-spacewalk coolant tank replacement process.

  7. Anderson during EVA 2

    NASA Image and Video Library

    2010-04-11

    ISS023-E-021569 (11 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, participates in the mission's second session of extravehicular activity (EVA) as construction and maintenance continue on the International Space Station. During the seven-hour, 26-minute spacewalk, Anderson and Rick Mastracchio (out of frame), mission specialist, unhooked and removed the depleted ammonia tank and installed a 1,700-pound ammonia tank on the station’s Starboard 1 truss, completing the second of a three-spacewalk coolant tank replacement process.

  8. Anderson and water bubble

    NASA Image and Video Library

    2010-04-12

    S131-E-009299 (12 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, watches a water bubble float freely between him and the camera, showing his image refracted, on the middeck of space shuttle Discovery while docked with the International Space Station.

  9. Anderson and water bubble

    NASA Image and Video Library

    2010-04-12

    S131-E-009277 (12 April 2010) --- NASA astronaut Clayton Anderson, STS-131 mission specialist, watches a water bubble float freely between him and the camera, showing his image refracted, on the middeck of space shuttle Discovery while docked with the International Space Station.

  10. Anderson Chern Insulators

    NASA Astrophysics Data System (ADS)

    He, James Jun; Zhou, Tong; Gu, Z. C.; Law, K. T.

    When a magnetic field is applied to a quantum spin Hall insulator (QSHI) without inversion symmetry, the edge states become gapful due to the breaking of time reversal symmetry (TRS) and the QSHI becomes a trivial spin Hall insulator (SHI) whose Chern number is N = 0 . In this work we show that disorder can drive such a SHI to a Chern insulator (CI) with N = 1 which supports a gapless chiral edge state. This CI exists in a finite range of disorder strength. Interestingly, the edge state is protected by the bulk mobility gap instead of an energy gap. For this reason, the new phase is called an Anderson Chern insulator (ACI).

  11. SSATA Crew Training (Clay Anderson)

    NASA Image and Video Library

    2009-11-05

    JSC2009-E-240528 (5 Nov. 2009) --- Astronaut Clayton Anderson, STS-131 mission specialist, participates in an Extravehicular Mobility Unit (EMU) spacesuit fit check in the Space Station Airlock Test Article (SSATA) in the Crew Systems Laboratory at NASA's Johnson Space Center. Astronaut Dorothy Metcalf-Lindenburger, mission specialist, assisted Anderson.

  12. SSATA Crew Training (Clay Anderson)

    NASA Image and Video Library

    2009-11-05

    JSC2009-E-240510 (5 Nov. 2009) --- Astronaut Clayton Anderson, STS-131 mission specialist, participates in an Extravehicular Mobility Unit (EMU) spacesuit fit check in the Space Station Airlock Test Article (SSATA) in the Crew Systems Laboratory at NASA's Johnson Space Center. Astronaut Dorothy Metcalf-Lindenburger, mission specialist; along with technicians assisting Anderson, are visible in the reflection in his helmet visor.

  13. SSATA Crew Training (Clay Anderson)

    NASA Image and Video Library

    2009-11-05

    JSC2009-E-240473 (5 Nov. 2009) --- Astronaut Clayton Anderson, STS-131 mission specialist, participates in an Extravehicular Mobility Unit (EMU) spacesuit fit check in the Space Station Airlock Test Article (SSATA) in the Crew Systems Laboratory at NASA's Johnson Space Center. Astronaut Dorothy Metcalf-Lindenburger, mission specialist, assisted Anderson.

  14. Gravitational Anderson localization.

    PubMed

    Rothstein, Ira Z

    2013-01-04

    We present a higher dimensional model where gravity is bound to a brane due to Anderson localization. The extra dimensions are taken to be a disordered crystal of branes, with randomly distributed tensions of order the fundamental scale. Such geometries bind the graviton and thus allow for arbitrarily large extra dimensions even when the curvature is small. Thus this model is quite distinct from that of Randall and Sundrum where localization is a consequence of curvature effects in the bulk. The hierarchy problem can be solved by having the standard model brane live a distance away from the brane on which the graviton is localized. The statistical properties of the system are worked out and it is shown that the scenario leads to a continuum of four dimensional theories with differing strengths of gravitational interactions. We live on one particular brane whose gravitational constant is G(N).

  15. Anderson attractors in active arrays

    PubMed Central

    Laptyeva, Tetyana V.; Tikhomirov, Andrey A.; Kanakov, Oleg I.; Ivanchenko, Mikhail V.

    2015-01-01

    In dissipationless linear media, spatial disorder induces Anderson localization of matter, light, and sound waves. The addition of nonlinearity causes interaction between the eigenmodes, which results in a slow wave diffusion. We go beyond the dissipationless limit of Anderson arrays and consider nonlinear disordered systems that are subjected to the dissipative losses and energy pumping. We show that the Anderson modes of the disordered Ginsburg-Landau lattice possess specific excitation thresholds with respect to the pumping strength. When pumping is increased above the threshold for the band-edge modes, the lattice dynamics yields an attractor in the form of a stable multi-peak pattern. The Anderson attractor is the result of a joint action by the pumping-induced mode excitation, nonlinearity-induced mode interactions, and dissipative stabilization. The regimes of Anderson attractors can be potentially realized with polariton condensates lattices, active waveguide or cavity-QED arrays. PMID:26304462

  16. Quantifying Anderson's fault types

    USGS Publications Warehouse

    Simpson, R.W.

    1997-01-01

    Anderson [1905] explained three basic types of faulting (normal, strike-slip, and reverse) in terms of the shape of the causative stress tensor and its orientation relative to the Earth's surface. Quantitative parameters can be defined which contain information about both shape and orientation [Ce??le??rier, 1995], thereby offering a way to distinguish fault-type domains on plots of regional stress fields and to quantify, for example, the degree of normal-faulting tendencies within strike-slip domains. This paper offers a geometrically motivated generalization of Angelier's [1979, 1984, 1990] shape parameters ?? and ?? to new quantities named A?? and A??. In their simple forms, A?? varies from 0 to 1 for normal, 1 to 2 for strike-slip, and 2 to 3 for reverse faulting, and A?? ranges from 0?? to 60??, 60?? to 120??, and 120?? to 180??, respectively. After scaling, A?? and A?? agree to within 2% (or 1??), a difference of little practical significance, although A?? has smoother analytical properties. A formulation distinguishing horizontal axes as well as the vertical axis is also possible, yielding an A?? ranging from -3 to +3 and A?? from -180?? to +180??. The geometrically motivated derivation in three-dimensional stress space presented here may aid intuition and offers a natural link with traditional ways of plotting yield and failure criteria. Examples are given, based on models of Bird [1996] and Bird and Kong [1994], of the use of Anderson fault parameters A?? and A?? for visualizing tectonic regimes defined by regional stress fields. Copyright 1997 by the American Geophysical Union.

  17. The Ecological Approach to Language Development: A Radical Solution to Chomsky's and Quine's Problems.

    ERIC Educational Resources Information Center

    Reed, Edward S.

    1995-01-01

    Asserts that several of the assumptions underlying Noam Chomsky's and W. V. O. Quine's theories of language acquisition and development are misleading or false. It is argued, among other things, that children do not "acquire" language, but rather learn how to participate in the linguistic community surrounding them. (99 references) (MDM)

  18. The Ecological Approach to Language Development: A Radical Solution to Chomsky's and Quine's Problems.

    ERIC Educational Resources Information Center

    Reed, Edward S.

    1995-01-01

    Asserts that several of the assumptions underlying Noam Chomsky's and W. V. O. Quine's theories of language acquisition and development are misleading or false. It is argued, among other things, that children do not "acquire" language, but rather learn how to participate in the linguistic community surrounding them. (99 references) (MDM)

  19. Quin2-induced metaphase arrest in stamen hair cells can be reversed by 1,2-dioctanoylglycerol but not by 1,3-dioctanoylglycerol.

    PubMed

    Larsen, P M; Chen, T L; Wolniak, S M

    1989-04-01

    Elicitor molecules of the polyphosphoinositide cycle, inositol 1,4,5-trisphosphate (InsP3) and 1,2-diacylglycerol (1,2-DAG) play roles in the entry of calcium into the cytosol and in the elevation of protein kinase C activity, respectively. We have treated stamen hair cells of the spiderwort plant, Tradescantia virginiana, with a solution of quin2 (50 microM) or its acetoxymethyl ester, quin2-AM (50 microM) and have retarded the normally predictable rate of progression through metaphase. Metaphase arrest persists for longer than 80 min after treatment with this Ca2+-chelator, and, shortly thereafter, the cells revert to interphase without dividing. Reversal of metaphase arrest results from treatments with calcium chloride (100 microM) after 5 to 8 min or with 1,2-DAG (i.e., 60 micrograms/ml 1,2-dioctanoylglycerol) after 7 to 11 min. In control experiments, metaphase arrest could not be reversed by treatment with either magnesium sulfate or 1,3-dioctanoylglycerol. Anaphase onset was observed in these control cells after post-treatment with calcium chloride (after 4-9 min) or with 1,2-dioctanoylglycerol (after 7-13 min). The treatment of stamen hair cells in very early prophase with H-7, (i.e., 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride), a potent protein kinase C inhibitor, extends the duration of metaphase significantly. Neither H-8 nor HA-1004, less active protein kinase C inhibitors in this class of molecules, alter the duration of metaphase to a significant extent. These results suggest that in cells arrested in metaphyase by quin2, calcium translocation plays a role in the sequence of events which culminate in anaphase.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. SSATA Crew Training (Clay Anderson)

    NASA Image and Video Library

    2009-11-05

    JSC2009-E-240471 (5 Nov. 2009) --- An empty Extravehicular Mobility Unit (EMU) spacesuit is photographed prior to a fit check with astronaut Clayton Anderson (out of frame), STS-131 mission specialist, in the Space Station Airlock Test Article (SSATA) in the Crew Systems Laboratory at NASA's Johnson Space Center.

  1. SSATA Crew Training (Clay Anderson)

    NASA Image and Video Library

    2009-11-05

    JSC2009-E-240509 (5 Nov. 2009) --- Astronaut Clayton Anderson, STS-131 mission specialist, participates in an Extravehicular Mobility Unit (EMU) spacesuit fit check in the Space Station Airlock Test Article (SSATA) in the Crew Systems Laboratory at NASA's Johnson Space Center.

  2. SSATA Crew Training (Clay Anderson)

    NASA Image and Video Library

    2009-11-05

    JSC2009-E-240514 (5 Nov. 2009) --- Astronaut Clayton Anderson, STS-131 mission specialist, participates in an Extravehicular Mobility Unit (EMU) spacesuit fit check in the Space Station Airlock Test Article (SSATA) in the Crew Systems Laboratory at NASA's Johnson Space Center.

  3. Anderson testifies on Planet Earth

    NASA Astrophysics Data System (ADS)

    Wainger, Lisa A.

    AGU president Don Anderson joined former astronaut Sally Ride and National Aeronautics and Space Administration official Lennard Fisk March 8 in testifying before the Senate committee on Commerce, Science, and Transportation. The three had been asked to speak on the future of the Mission to Planet Earth, proposed both in a National Academy of Sciences report and a NASA study.Anderson was chairman of the National Academy of Science's Task Group on Earth Sciences, which prepared the report Mission to Planet Earth as part of the series Space Science in the Twenty-First Century. In his testimony, Anderson highlighted parts of the report and quoted the frontispiece “We now have the technology and the incentive to move boldly forward on a Mission to Planet Earth. We call on the nation to implement an integrated global program using both spaceborne and earth-based instrumentation for fundamental research on the origin, evolution and nature of our planet, its place in our solar system, and its interaction with living things, including mankind.”

  4. QuIN: A Web Server for Querying and Visualizing Chromatin Interaction Networks

    PubMed Central

    Thibodeau, Asa; Márquez, Eladio J.; Luo, Oscar; Ruan, Yijun; Shin, Dong-Guk; Stitzel, Michael L.; Ucar, Duygu

    2016-01-01

    Recent studies of the human genome have indicated that regulatory elements (e.g. promoters and enhancers) at distal genomic locations can interact with each other via chromatin folding and affect gene expression levels. Genomic technologies for mapping interactions between DNA regions, e.g., ChIA-PET and HiC, can generate genome-wide maps of interactions between regulatory elements. These interaction datasets are important resources to infer distal gene targets of non-coding regulatory elements and to facilitate prioritization of critical loci for important cellular functions. With the increasing diversity and complexity of genomic information and public ontologies, making sense of these datasets demands integrative and easy-to-use software tools. Moreover, network representation of chromatin interaction maps enables effective data visualization, integration, and mining. Currently, there is no software that can take full advantage of network theory approaches for the analysis of chromatin interaction datasets. To fill this gap, we developed a web-based application, QuIN, which enables: 1) building and visualizing chromatin interaction networks, 2) annotating networks with user-provided private and publicly available functional genomics and interaction datasets, 3) querying network components based on gene name or chromosome location, and 4) utilizing network based measures to identify and prioritize critical regulatory targets and their direct and indirect interactions. AVAILABILITY: QuIN’s web server is available at http://quin.jax.org QuIN is developed in Java and JavaScript, utilizing an Apache Tomcat web server and MySQL database and the source code is available under the GPLV3 license available on GitHub: https://github.com/UcarLab/QuIN/. PMID:27336171

  5. Interview with Philip W. Anderson

    SciTech Connect

    Anderson, P.W.

    1988-08-01

    Phil Anderson, Professor of Physics at Princeton University, has devoted his career to research in theoretical physics. He is a member of the National Academy of Science and the American Academy of Arts and Sciences, a foreign member of the Royal Society, and a foreign associate of the Accademia Lincei in Rome. The Americal Physical Society awarded him the Oliver E. Buckley Solid State Physics Prize in 1964. In 1977 he won the Nobel Prize in Physics with J.H. van Vleck and N.F. Mott. His work has encompassed a broad range of subjects: quantum theory of condensed matter, broken symmetry, transport theory and localization, random statistical systems, spectral line broadening, superfluidity in helium and neutron stars, magnetism, and superconductivity. His avocations include ''hiking, the game of GO, Romanesque architecture, and the human condition.'' In this interview he explains his RVB theory of the oxide superconductors and its historical context.

  6. Price-Anderson Law - reports on Price-Anderson issues

    SciTech Connect

    Not Available

    1985-01-01

    Five of the six papers in this study are by experts outside the nuclear industry, and deal with fear, risk, and risk management as they apply to the review of the Price-Anderson Act. The purpose of the Act is to encourage private enterprise to develop a reliable source of electric power and to protect the public from the financial consequences of injury or damage that may occur during the process. The titles of the five papers are: (1) the effects of ionizing radiation on human health, (2) proof of causation through expert opinion evidence in low-level radiation cases, (3) a critical review of the probability of causation method, (4) the nuclear liability claims experience of the nuclear insurance pools, (5) review of nuclear liability compensation systems applicable to reactors outside the United States, and (6) the economic foundations of limited liability for nuclear reactor accidents. A separate abstract was prepared for each of the papers for EDB, EPA, and INS.

  7. Light focusing in the Anderson regime

    NASA Astrophysics Data System (ADS)

    Leonetti, Marco; Karbasi, Salman; Mafi, Arash; Conti, Claudio

    2014-07-01

    Anderson localization is a regime in which diffusion is inhibited and waves (also electromagnetic waves) get localized. Here we exploit adaptive optics to achieve focusing in disordered optical fibres in the Anderson regime. By wavefront shaping and optimization, we observe the generation of a propagation-invariant beam, where light is trapped transversally by disorder, and show that Anderson localizations can be also excited by extended speckled beams. We demonstrate that disordered fibres allow a more efficient focusing action with respect to standard fibres in a way independent of their length, because of the propagation-invariant features and cooperative action of transverse localizations.

  8. Taking on Titan: Meet Carrie Anderson

    NASA Image and Video Library

    When she was a little girl, Carrie Anderson dreamed of becoming an astronomer. Now, as a space scientist at NASA Goddard Space Flight Center, Carrie studies the atmosphere on Titan: one of Saturn's...

  9. Schemata, Cognitive Structure, and Advance Organizers: A Reply to Anderson, Spiro, and Anderson.

    ERIC Educational Resources Information Center

    Ausubel, David P.

    1980-01-01

    Anderson, Spiro, and Anderson (EJ 189 658) assert that the author's assimilation theory of meaningful learning and retention is "hopelessly vague." Documented examination of these assertions indicates that they are unspecified, unsubstantiated, undocumented, and based on indisputable misrepresentation of published material and on logical…

  10. Anderson Localization and the Electron Glass

    NASA Astrophysics Data System (ADS)

    Pastor, A. A.; Dobrosavljevic, V.

    2000-03-01

    In recent work [1], we have formulated a dynamical mean-field (DMF) approach to the electron glass problem, which is exact in the large coordination limit. However, this theory ignores Anderson localization effects, since it reduces to the CPA formulation in the limit of noninteracting electrons. In the present study, we extend our formulation to incorporate Anderson localization in a fashion similar to the previous DMF approaches to the Mott-Anderson transition [2]. We find that localization strongly enhances the glass phase, and stabilizes the existence of the Coulomb gap in the entire insulating region. Interstingly, our formulation suggests the existence of an intermediate metallic glass phase, which is expected to display non-Fermi liquid features. [1] A. A. Pastor and V. Dobrosavljevic, Phys. Rev. Lett. 83, 4642 (1999). [2] V. Dobrosavljevic and G. Kotliar, Phys. Rev. Lett. 78, 3943 (1997).

  11. FE Anderson exercising on the CEVIS during STS-118/Expedition 15 Joint Operations

    NASA Image and Video Library

    2007-08-16

    S118-E-07657 (16 Aug. 2007) --- Astronaut Clayton Anderson, Expedition 15 flight engineer, exercises on the Cycle Ergometer with Vibration Isolation System (CEVIS) in the Destiny laboratory of the International Space Station while Space Shuttle Endeavour remains docked with the station.

  12. Anderson localization in the time domain

    NASA Astrophysics Data System (ADS)

    Sacha, Krzysztof; Delande, Dominique

    2016-08-01

    In analogy with the usual Anderson localization taking place in time-independent disordered quantum systems where the disorder acts in configuration space, systems exposed to temporally disordered potentials can display Anderson localization in the time domain. We demonstrate this phenomenon with one-dimensional examples where a temporally disordered potential induces localization during the quantum evolution of wave packets, in contrast with a fully delocalized classical dynamics. This is an example of a time crystal phenomenon, i.e., a crystalline behavior in the time domain.

  13. W-5 and quin 2-AM reverse the inhibitory effect of insulin on lipolysis due to dibutyryl cAMP.

    PubMed

    Goko, H; Matsuoka, A

    1999-05-01

    The effects of W-5, a weak calmodulin antagonist, and quin 2-AM, a cell permeant calcium chelator, on lipolysis and antilipolytic activity of insulin were studied in isolated rat adipocytes. We have previously shown that W-7, a strong calmodulin antagonist, suppresses the inhibitory effect of insulin on lipolysis due to dibutyryl cAMP (Bt2cAMP) in a dose-dependent manner [H. Goko, A. Matsuoka, Diabetes Res. Clin. Prac. 19 (1993) 177-181] and verapamil, a calcium antagonist, potentiates lipolysis due to Bt2cAMP. Like W-7, W-5 suppressed the antilipolytic action of insulin on lipolysis due to Bt2cAMP in a dose-dependent manner. However, when lipolysis was potentiated with 3-isobutyryl-1-methylxanthine (IBMX), W-5 did not suppress the antilipolytic action of insulin. At the same time, like verapamil, W-5 also potentiated lipolysis due to Bt2cAMP in a dose-dependent manner. Thus W-5 has the pharmaceutical effects of both W-7 and verapamil. The chelation of intracellular Ca2+ in adipocytes with quin 2-AM also produced a dose-dependent potentiation of lipolysis due to Bt2cAMP and suppression of the antilipolytic action of insulin on lipolysis due to Bt2cAMP. These effects of quin 2-AM are the same as those of W-5. Therefore, our results suggest that the cytoplasmic Ca2+ plays a pivotal role in mediating the potentiation of lipolysis and antilipolytic action of insulin when lipolysis is induced by Bt2cAMP in rat adipocytes and that W-5 appears to exert its pharmaceutical effects through the inhibition of intracellular calcium-dependent steps other than calmodulin.

  14. 27 CFR 9.86 - Anderson Valley.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Anderson Valley. 9.86 Section 9.86 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas §...

  15. MS Anderson works with three middeck payloads

    NASA Image and Video Library

    1998-03-03

    S89-E-5207 (25 Jan 1998) --- This Electronic Still Camera (ESC) image shows astronaut Michael P. Anderson, mission specialist, checking the Biotechnology Refrigerator (BTR) while transferring logistics onboard the Space Shuttle Endeavour. This ESC view was taken on January 25, 1998, at 18:56:29 GMT.

  16. Anderson and Whitson in the SM

    NASA Image and Video Library

    2007-11-04

    ISS016-E-009700 (4 Nov. 2007) --- Astronaut Clay Anderson, STS-120 mission specialist, prepares to eat a meal at the galley in the Zvezda Service Module of the International Space Station while Space Shuttle Discovery is docked with the station. Astronaut Peggy Whitson, Expedition 16 commander, is at right.

  17. Wheelock and Anderson in Quest airlock

    NASA Image and Video Library

    2006-10-25

    S120-E-006449 (25 Oct. 2007) --- Astronauts Doug Wheelock (left), STS-120 mission specialist, and Clay Anderson, Expedition 16 flight engineer, hold cameras in the hatch of the Quest Airlock of the International Space Station while Space Shuttle Discovery is docked with the station.

  18. The Châtelperronian conundrum: Blade and bladelet lithic technologies from Quinçay, France.

    PubMed

    Roussel, M; Soressi, M; Hublin, J-J

    2016-06-01

    The discovery of an almost complete Neanderthal skeleton in a Châtelperronian context at Saint-Césaire 35 years ago changed our perspective on the beginning of the Upper Paleolithic in western Europe. Since then, the Châtelperronian has generally been considered a "transitional" industry rather than an Upper or a Middle Paleolithic industry because of its chronological position, and the association of Neanderthal remains with blades, bone tools and personal ornaments. Several competing hypotheses have been proposed to explain the association between Neanderthals and these types of artefacts including post-depositional mixing, acculturation from anatomically modern human populations, or an independent technological evolution by local Neanderthal populations. Quinçay Cave is the only Châtelperronian site where personal ornaments have been found that does not contain an overlying Upper Paleolithic layer. This means that the post-depositional mixing of later elements into the Châtelperronian may not be used as an explanation for the presence of these materials. We report here on a detailed technological analysis of lithic artefacts from the three Châtelperronian layers at Quinçay Cave. We compare our results with the technology of Mousterian blade industries dating to OIS (oxygen isotope stage) 5, the Mousterian of Acheulian Tradition type B, and the Proto-Aurignacian. We show that the Châtelperronian is sufficiently divergent from the Middle Paleolithic to be classified as a fully Upper Paleolithic industry, with a focus on blade and bladelet production. We also show that the Quinçay Châtelperronian includes retouched bladelets that resemble those found in the Proto-Aurignacian, but were produced in a different manner. We argue that a technological convergence cannot account for these behaviors, since the specific type of retouched bladelet associated with the Châtelperronian was also regularly used by Proto-Aurignacian of neighboring regions. We suggest

  19. Price-Anderson Act: Congressional review begins

    SciTech Connect

    Not Available

    1984-07-05

    Every 10 years Congress reviews, amends, and extends the Price-Anderson Act of 1957, which was designed to encourage the new nuclear industry by guaranteeing insurance beyond the level provided by private insurers. The Nuclear Regulatory Commission is recommending five congressional actions for the 1987 extension: reauthorization, replacement of the absolute insurance limitation with an annual limitation of liability, raising the retrospective premium per reactor per incident from $5 million to $10 million, raising the statute of limitations on claims for 20 to 30 years, and retaining current language dealing with extraordinary events. Two bills, H.R. 421 and H.R. 3277, were introduced with provisions that broaden the opportunity for victims compensation and eliminate the subsidy aspect. Hearings began in July, with reactions from the National Taxpayers Union and Nuclear insurance underwriters in conflict over the limitations on liability. DOE and DOE contractors urge continuation of the Price-Anderson limitation.

  20. Anderson localization for chemically realistic systems

    NASA Astrophysics Data System (ADS)

    Terletska, Hanna

    2015-03-01

    Disorder which is ubiquitous for most materials can strongly effect their properties. It may change their electronic structures or even cause their localization, known as Anderson localization. Although, substantial progress has been achieved in the description of the Anderson localization, a proper mean-field theory of this phenomenon for more realistic systems remains elusive. Commonly used theoretical methods such as the coherent potential approximation and its cluster extensions fail to describe the Anderson transition, as the average density of states (DOS) employed in such theories is not critical at the transition. However, near the transition, due to the spatial confinement of carriers, the local DOS becomes highly skewed with a log-normal distribution, for which the most probable and the typical values differ noticeably from the average value. Dobrosavljevic et.al., incorporated such ideas in their typical medium theory (TMT), and showed that the typical (not average) DOS is critical at the transition. While the TMT is able to capture the localized states, as a local single site theory it still has several drawbacks. For the disorder Anderson model in three dimension it underestimates the critical disorder strength, and fails to capture the re-entrance behavior of the mobility edge. We have recently developed a cluster extension of the TMT, which addresses these drawbacks by systematically incorporating non-local corrections. This approach converges quickly with cluster size and allows us to incorporate the effect of interactions and realistic electronic structure. As the first steps towards realistic material modeling, we extended our TMDCA formalisms to systems with the off diagonal disorder and multiple bands structures. We also applied our TMDCA scheme to systems with both disorder and interactions and found that correlations effects tend to stabilize the metallic behavior even in two dimensions. This work was supported by DOE SciDAC Grant No. DE-FC02

  1. Order Parameter Theory for Anderson Localization

    NASA Astrophysics Data System (ADS)

    Dobrosavljevic, Vladimir; Pastor, Andrei

    2001-03-01

    The Anderson metal-insulator transition is well known to display many similarities to standard critical phenomena, yet an obvious order parameter has remained difficult to find. In this work, we demonstrate that a relevant local order parameter can be defined and self-consistently determined, providing a simple and physically transparent picture of the Anderson transition. Our formulation proceeds in close analogy with the well-known coherent potential approximation (CPA), with a small but crucial difference. Our theory self-consistently calculates not the average but instead the typical local density of states, which serves as the order parameter, and is found to vanish at the Anderson transition. As a result, we show that both the escape rate of an electron from a given site, and the conductivity vanish in the insulating phase, which emerges for disorder strengths comparable to the electronic bandwidth. Due to the local character of our theory, it can easily be combined with standard dynamical mean-field approaches for strong electronic correlations, thus opening an attractive avenue for the study of the interplay (A. A. Pastor and V. Dobrosavljevic, Phys. Rev. Lett. 83), 4642 (1999) ( V. Dobrosavljevic and G. Kotliar, Phys. Rev. Lett. 78), 3943 (1997) of interaction and disorder.

  2. Deliberate quin2 overload as a method for in situ characterization of active calcium extrusion systems and cytoplasmic calcium binding: application to the human platelet.

    PubMed

    Johansson, J S; Haynes, D H

    1988-09-01

    The objectives of the title were accomplished by a four-step experimental procedure followed by a simple graphical and mathematical analysis. Platelets are (i) overloaded with the indicator quin2 to cytoplasmic concentrations of 2.9 mM and (ii) are exposed to 2 mM external Ca2+ and 1.0 microM ionomycin to rapidly achieve cytoplasmic Ca2+ ([Ca2+]cyt) of ca. 1.5 microM. (iii) The external Ca2+ is removed by EGTA addition, and (iv) the active Ca2+ extrusion process is then monitored as a function of time. Control experiments show that the ionophore shunts dense tubular uptake and does not contribute to the Ca2+ efflux process during phases iii-iv and that the extrusion process is sensitive to metabolic inhibitors. The progress curves for the decline of quin2 fluorescence (resulting from active Ca2+ extrusion) were analyzed as a function of [Ca2+]cyt using a mathematical model involving the probability that an exported Ca2+ was removed from a quin2 complex (vs. a cytoplasmic binding element). The observed rates of decline of quin2 fluorescence at a particular [Ca2+]cyt are dependent upon (i) the absolute rate of the extrusion system (a function of its Km, Vm and Hill coefficient (n)), (ii) the intrinsic Ca2+ buffer capacity of the cytoplasm (a function of the total site concentration ([B]T) and its Kd) and (iii) the buffer capacity of the intracytoplasmic quin2 (a function of its concentration and Kd). The contribution of (iii) was known and varied and was used to determine (ii) and (i) as a function of [Ca2+]cyt. The Ca2+ binding data were verified by 45Ca2+ experimentation.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. MS Anderson checks on the CEBAS

    NASA Image and Video Library

    1998-01-22

    STS089-357-003 (22-31 Jan. 1998) --- Astronaut Michael P. Anderson, STS-89 mission specialist, works on Endeavour's middeck with the Closed Equilibrated Biological Aquatic System (CEBAS), an experiment developed by the German Space Agency (DLR). The CEBAS mini-module, a middeck habitat for aquatic organisms, enables scientists to conduct various gravity-related experiments in the areas of zoology, botany and developmental biology, as well as in interdisciplinary areas such as scientific research on artificial ecosystems. Photo credit: NASA

  4. Astronaut Clay Anderson Speaks With S.C. Students

    NASA Image and Video Library

    From NASA's International Space Station Mission Control Center, NASA astronaut Clay Anderson participates in a Digital Learning Network (DLN) event with students at Crayton Middle School, Columbia,...

  5. Superconducting parity effect across the Anderson limit

    PubMed Central

    Vlaic, Sergio; Pons, Stéphane; Zhang, Tianzhen; Assouline, Alexandre; Zimmers, Alexandre; David, Christophe; Rodary, Guillemin; Girard, Jean-Christophe; Roditchev, Dimitri; Aubin, Hervé

    2017-01-01

    How small can superconductors be? For isolated nanoparticles subject to quantum size effects, P.W. Anderson in 1959 conjectured that superconductivity could only exist when the electronic level spacing δ is smaller than the superconducting gap energy Δ. Here we report a scanning tunnelling spectroscopy study of superconducting lead (Pb) nanocrystals grown on the (110) surface of InAs. We find that for nanocrystals of lateral size smaller than the Fermi wavelength of the 2D electron gas at the surface of InAs, the electronic transmission of the interface is weak; this leads to Coulomb blockade and enables the extraction of electron addition energy of the nanocrystals. For large nanocrystals, the addition energy displays superconducting parity effect, a direct consequence of Cooper pairing. Studying this parity effect as a function of nanocrystal volume, we find the suppression of Cooper pairing when the mean electronic level spacing overcomes the superconducting gap energy, thus demonstrating unambiguously the validity of the Anderson criterion. PMID:28240294

  6. Valence transition in the periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Hübsch, A.; Becker, K. W.

    2006-08-01

    A very rich phase diagram has recently been found in CeCu2Si2 from high pressure experiments where, in particular, a transition between an intermediate valence configuration and an integral valent heavy fermion state has been observed. We show that such a valence transition can be understood in the framework of the periodic Anderson model. In particular, our results show a breakdown of a mixed-valence state which is accompanied by a drastic change in the f occupation in agreement with experiment. This valence transition can possibly be interpreted as a collapse of the large Fermi surface of the heavy fermion state which incorporates not only the conduction electrons but also the localized f electrons. The theoretical approach used in this paper is based on the novel projector-based renormalization method (PRM). With respect to the periodic Anderson model, the method was before only employed in combination with the basic approximations of the well-known slave-boson mean-field theory. In this paper, the PRM treatment is performed in a more sophisticated manner where both mixed as well as integral valent solutions have been obtained. Furthermore, we argue that the presented PRM approach might be a promising starting point to study the competing interactions in CeCu2Si2 and related compounds.

  7. Distribution of critical temperature at Anderson localization

    NASA Astrophysics Data System (ADS)

    Gammag, Rayda; Kim, Ki-Seok

    2016-05-01

    Based on a local mean-field theory approach at Anderson localization, we find a distribution function of critical temperature from that of disorder. An essential point of this local mean-field theory approach is that the information of the wave-function multifractality is introduced. The distribution function of the Kondo temperature (TK) shows a power-law tail in the limit of TK→0 regardless of the Kondo coupling constant. We also find that the distribution function of the ferromagnetic transition temperature (Tc) gives a power-law behavior in the limit of Tc→0 when an interaction parameter for ferromagnetic instability lies below a critical value. However, the Tc distribution function stops the power-law increasing behavior in the Tc→0 limit and vanishes beyond the critical interaction parameter inside the ferromagnetic phase. These results imply that the typical Kondo temperature given by a geometric average always vanishes due to finite density of the distribution function in the TK→0 limit while the typical ferromagnetic transition temperature shows a phase transition at the critical interaction parameter. We propose that the typical transition temperature serves a criterion for quantum Griffiths phenomena vs smeared transitions: Quantum Griffiths phenomena occur above the typical value of the critical temperature while smeared phase transitions result at low temperatures below the typical transition temperature. We speculate that the ferromagnetic transition at Anderson localization shows the evolution from quantum Griffiths phenomena to smeared transitions around the critical interaction parameter at low temperatures.

  8. Localization and transport in a strongly driven Anderson insulator

    NASA Astrophysics Data System (ADS)

    Agarwal, Kartiek; Ganeshan, Sriram; Bhatt, R. N.

    2017-07-01

    We study localization and charge dynamics in a monochromatically driven one-dimensional Anderson insulator focusing on the low-frequency, strong-driving regime. We study this problem using a mapping of the Floquet Hamiltonian to a hopping problem with correlated disorder in one higher harmonic-space dimension. We show that (i) resonances in this model correspond to adiabatic Landau-Zener (LZ) transitions that occur due to level crossings between lattice sites over the course of dynamics; (ii) the proliferation of these resonances leads to dynamics that appear diffusive over a single drive cycle, but the system always remains localized; (iii) actual charge transport occurs over many drive cycles due to slow dephasing between these LZ orbits and is logarithmic in time, with a crucial role being played by far-off Mott-like resonances; and (iv) applying a spatially varying random phase to the drive tends to decrease localization, suggestive of weak-localization physics. We derive the conditions for the strong-driving regime, determining the parametric dependencies of the size of Floquet eigenstates, and time scales associated with the dynamics, and corroborate the findings using both numerical scaling collapses and analytical arguments.

  9. Local theory for Mott-Anderson localization

    NASA Astrophysics Data System (ADS)

    Sen, Sudeshna; Terletska, Hanna; Moreno, Juana; Vidhyadhiraja, N. S.; Jarrell, Mark

    2016-12-01

    The paramagnetic metallic phase of the Anderson-Hubbard model (AHM) is investigated using a nonperturbative local moment approach within the framework of dynamical mean-field theory with a typical medium. Our focus is on the breakdown of the metallic phase near the metal-insulators transition as seen in the single-particle spectra, scattering rates, and the associated distribution of Kondo scales. We demonstrate the emergence of a universal, underlying low-energy scale, TKpeak. This lies close to the peak of the distribution of Kondo scales obtained within the metallic phase of the paramagnetic AHM. Spectral dynamics for energies ω ≲TKpeak display Fermi liquid universality crossing over to an incoherent universal dynamics for ω ≫TKpeak in the scaling regime. Such universal dynamics indicate that within a local theory the low to moderately low-energy physics is governed by an effective, disorder renormalized Kondo screening.

  10. Cutaneous complications of Anderson-Fabry disease.

    PubMed

    Giuseppe, Pistone; Daniele, Rizzo; Rita, Bongiorno Maria

    2013-01-01

    Anderson-Fabry disease is an X-linked lysosomal storage disorder caused by a defect in the α-galactosidase A gene, which leads to the deficiency of the hydrolytic enzyme α-galactosidase A. The consequent inability to catabolize glycosphingolipids causes progressive accumulation of globotriaosylceramide in the vascular endothelium throughout the body. Fatalities in the classical phenotype may usually occur as a consequence of cerebral, cardiac or renal disease. Dermatological manifestations are a relevant feature of Fabry disease and include angiokeratomas, telangiectasiae, lymphedema, anhidrosis or hypohidrosis and pseudo-acromegalic facial appearance. The actual causal treatment for Fabry disease is the enzyme replacement therapy. Dermatologists have a key role, since cutaneous manifestations may lead to the diagnosis. This may help an early therapeutic intervention, reducing both morbidity and mortality.

  11. Slow Relaxation in Anderson Critical Systems

    NASA Astrophysics Data System (ADS)

    Choi, Soonwon; Yao, Norman; Choi, Joonhee; Kucsko, Georg; Lukin, Mikhail

    2016-05-01

    We study the single particle dynamics in disordered systems with long range hopping, focusing on the critical cases, i.e., the hopping amplitude decays as 1 /rd in d-dimension. We show that with strong on-site potential disorder, the return probability of the particle decays as power-law in time. As on-site potential disorder decreases, the temporal profile smoothly changes from a simple power-law to the sum of multiple power-laws with exponents ranged from 0 to νmax. We analytically compute the decay exponents using a simple resonance counting argument, which quantitatively agrees with exact numerical results. Our result implies that the dynamics in Anderson Critical systems are dominated by resonances. Harvard-MIT CUA, Kwanjeong Educational Fellowship, AFOSR MURI, Samsung Scholarship.

  12. Interaction-Tuned Anderson versus Mott Localization

    NASA Astrophysics Data System (ADS)

    Antipov, Andrey E.; Javanmard, Younes; Ribeiro, Pedro; Kirchner, Stefan

    2016-09-01

    Disorder or sufficiently strong interactions can render a metallic state unstable, causing it to turn into an insulating one. Despite the fact that the interplay of these two routes to a vanishing conductivity has been a central research topic, a unifying picture has not emerged so far. Here, we establish that the two-dimensional Falicov-Kimball model, one of the simplest lattice models of strong electron correlation, does allow for the study of this interplay. In particular, we show that this model at particle-hole symmetry possesses three distinct thermodynamic insulating phases and exhibits Anderson localization. The previously reported metallic phase is identified as a finite-size feature due to the presence of weak localization. We characterize these phases by their electronic density of states, staggered occupation, conductivity, and the generalized inverse participation ratio. The implications of our findings for other strongly correlated systems are discussed.

  13. Energy transport in the Anderson insulator

    NASA Astrophysics Data System (ADS)

    Gutman, D. B.; Protopopov, I. V.; Burin, A. L.; Gornyi, I. V.; Santos, R. A.; Mirlin, A. D.

    2016-06-01

    We study the heat conductivity in Anderson insulators in the presence of a power-law interaction. Particle-hole excitations built on localized electron states are viewed as two-level systems randomly distributed in space and energy and coupled due to electron-electron interaction. A small fraction of these states form resonant pairs that in turn build a complex network allowing for energy propagation. We identify the character of energy transport through this network and evaluate the thermal conductivity. For physically relevant cases of two-dimensional and three-dimensional spin systems with 1 /r3 dipole-dipole interaction (originating from the conventional 1 /r Coulomb interaction between electrons), the found thermal conductivity κ scales with temperature as κ ∝T3 and κ ∝T4 /3 , respectively. Our results may be of relevance also to other realizations of random spin Hamiltonians with long-range interactions.

  14. The Role of Contrast in the Perception of Achromatic Transparency: Comment on Singh and Anderson (2002) and Anderson (2003)

    ERIC Educational Resources Information Center

    Albert, Marc K.

    2008-01-01

    M. Singh and B. L. Anderson proposed a perceptual theory of achromatic transparency in which the perceived transmittance of a perceived transparent filter is determined by the ratio of the Michelson contrast seen in the region of transparency to that of the background seen directly. Subsequently, B. L. Anderson, M. Singh, and J. Meng proposed that…

  15. The Role of Contrast in the Perception of Achromatic Transparency: Comment on Singh and Anderson (2002) and Anderson (2003)

    ERIC Educational Resources Information Center

    Albert, Marc K.

    2008-01-01

    M. Singh and B. L. Anderson proposed a perceptual theory of achromatic transparency in which the perceived transmittance of a perceived transparent filter is determined by the ratio of the Michelson contrast seen in the region of transparency to that of the background seen directly. Subsequently, B. L. Anderson, M. Singh, and J. Meng proposed that…

  16. Geology of the Anderson Mesa quadrangle, Colorado

    USGS Publications Warehouse

    Cater, Fred W.; Withington, C.F.

    1953-01-01

    The Anderson Mesa quadrangle is one of the eighteen 7 1/2-minute quadrangles covering the principal carnotite-producing area of the southwestern Colorado. The geology of these quadrangles was mapped by the U.S. Geological Survey for the Atomic Energy Commission as part of a comprehensive study of carnotite deposits. The rocks exposed in the eighteenth quadrangles consist of crystalline rocks of pre-Cambrian age and sedimentary rocks that range in age from late Paleozoic to Quarternary. Over much of the area the sedimentary rocks are flat lying, but in places the rocks are disrupted by high-angle faults, and northwest-tending folds. Conspicuous among the folds are large anticlines having cores of intrusive slat and gypsum. Most of the carnotite deposits are confined to the Salt Wash sandstone member of the Jurassic Morrison formation. Within this sandstone, most of the deposits are spottily distributed through an arcuate zone known as the "Uravan Mineral Belt". Individual deposits range in size from irregular masses containing many thousands of tons. The ore consists of largely of sandstone selectively impregnated and in part replaced by uranium and vanadium minerals. Most of the deposits appear to be related to certain sedimentary structures in sandstones of favorable composition.

  17. Anderson-Fabry disease in children.

    PubMed

    Sestito, Simona; Ceravolo, Ferdinando; Concolino, Daniela

    2013-01-01

    Although clinical evidence of major organ damage is typical of adulthood, many of the signs and symptoms of Anderson Fabry Disease (AFD) occur frequently in childhood. The clinical phenotype of AFD in pediatric patients has been described in several studies which show a higher incidence and an earlier onset of symptoms in male patients than in females. These include neurological manifestations (acroparaesthesias, chronic neuropathic pain, hypo-anhidrosis, tinnitus, hearing, loss), gastrointestinal (GI) symptoms (abdominal pain and diarrhea), angiokeratomas, ocular abnormalities (cornea verticillata, tortuous retinal vessels and subcapsular cataracts). Such manifestations may impair quality of life and, because of their unspecific nature, rarely lead to an early diagnosis. In addition, signs of major organ damage (microalbuminuria or proteinuria, urinary hyperfiltration, impaired heart rate variability, left ventricular hypertrophy, stroke) are encountered in children with AFD. Clinical trials of enzyme replacement therapy (ERT) with agalsidase alfa and agalsidase beta have been conducted in children, with clinical and pharmacodinamc effects proved by both enzyme formulations, whereas differences in safety profile and administration were found. Although several studies suggest that ERT should be started before irreversible damage in critical organs have occurred, the issue of when to initiate it has not yet been resolved. More controlled trials must be done in order to demonstrate that an early start of ERT could prevent adult complications and to assess the optimal timing of treatment in children with AFD. This review aims to provide an update of the current understanding for a better approach of pediatric AFD.

  18. Mott transitions in the periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Logan, David E.; Galpin, Martin R.; Mannouch, Jonathan

    2016-11-01

    The periodic Anderson model (PAM) is studied within the framework of dynamical mean-field theory, with particular emphasis on the interaction-driven Mott transition it contains, and on resultant Mott insulators of both Mott-Hubbard and charge-transfer type. The form of the PAM phase diagram is first deduced on general grounds using two exact results, over the full range of model parameters and including metallic, Mott, Kondo and band insulator phases. The effective low-energy model which describes the PAM in the vicinity of a Mott transition is then shown to be a one-band Hubbard model, with effective hoppings that are not in general solely nearest neighbour, but decay exponentially with distance. This mapping is shown to have a range of implications for the physics of the problem, from phase boundaries to single-particle dynamics; all of which are confirmed and supplemented by NRG calculations. Finally we consider the locally degenerate, non-Fermi liquid Mott insulator, to describe which requires a two-self-energy description. This is shown to yield a number of exact results for the associated local moment, charge, and interaction-renormalised levels, together with a generalisation of Luttinger’s theorem to the Mott insulator.

  19. Scaling analysis of Anderson localizing optical fibers

    NASA Astrophysics Data System (ADS)

    Abaie, Behnam; Mafi, Arash

    2017-02-01

    Anderson localizing optical fibers (ALOF) enable a novel optical waveguiding mechanism; if a narrow beam is scanned across the input facet of the disordered fiber, the output beam follows the transverse position of the incoming wave. Strong transverse disorder induces several localized modes uniformly spread across the transverse structure of the fiber. Each localized mode acts like a transmission channel which carries a narrow input beam along the fiber without transverse expansion. Here, we investigate scaling of transverse size of the localized modes of ALOF with respect to transverse dimensions of the fiber. Probability density function (PDF) of the mode-area is applied and it is shown that PDF converges to a terminal shape at transverse dimensions considerably smaller than the previous experimental implementations. Our analysis turns the formidable numerical task of ALOF simulations into a much simpler problem, because the convergence of mode-area PDF to a terminal shape indicates that a much smaller disordered fiber, compared to previous numerical and experimental implementations, provides all the statistical information required for the precise analysis of the fiber.

  20. Anderson prepares for a HAM Radio session in the SM

    NASA Image and Video Library

    2007-09-14

    ISS015-E-28715 (14 Sept. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, uses a communication system while checking a procedures checklist in the Zvezda Service Module of the International Space Station.

  1. Topological approximation of the nonlinear Anderson model

    NASA Astrophysics Data System (ADS)

    Milovanov, Alexander V.; Iomin, Alexander

    2014-06-01

    We study the phenomena of Anderson localization in the presence of nonlinear interaction on a lattice. A class of nonlinear Schrödinger models with arbitrary power nonlinearity is analyzed. We conceive the various regimes of behavior, depending on the topology of resonance overlap in phase space, ranging from a fully developed chaos involving Lévy flights to pseudochaotic dynamics at the onset of delocalization. It is demonstrated that the quadratic nonlinearity plays a dynamically very distinguished role in that it is the only type of power nonlinearity permitting an abrupt localization-delocalization transition with unlimited spreading already at the delocalization border. We describe this localization-delocalization transition as a percolation transition on the infinite Cayley tree (Bethe lattice). It is found in the vicinity of the criticality that the spreading of the wave field is subdiffusive in the limit t →+∞. The second moment of the associated probability distribution grows with time as a power law ∝ tα, with the exponent α =1/3 exactly. Also we find for superquadratic nonlinearity that the analog pseudochaotic regime at the edge of chaos is self-controlling in that it has feedback on the topology of the structure on which the transport processes concentrate. Then the system automatically (without tuning of parameters) develops its percolation point. We classify this type of behavior in terms of self-organized criticality dynamics in Hilbert space. For subquadratic nonlinearities, the behavior is shown to be sensitive to the details of definition of the nonlinear term. A transport model is proposed based on modified nonlinearity, using the idea of "stripes" propagating the wave process to large distances. Theoretical investigations, presented here, are the basis for consistency analysis of the different localization-delocalization patterns in systems with many coupled degrees of freedom in association with the asymptotic properties of the

  2. Louisa Garrett Anderson (1873-1943), surgeon and suffragette.

    PubMed

    Geddes, Jennian F

    2008-11-01

    Louisa Garrett Anderson, daughter of Britain's first woman doctor, has been largely forgotten today despite the fact that her contribution to the women's movement was as great as that of her mother. Recognized by her contemporaries as an important figure in the suffrage campaign, Anderson chose to lend her support through high-profile action, being one of the few women doctors in her generation who risked their professional as well as their personal reputation in the fight for women's rights by becoming a suffragette - in her case, even going so far as to spend a month in prison for breaking a window on a demonstration. On the outbreak of war, with only the clinical experience she had gained as outpatient surgeon in a women's hospital, Anderson established a series of women-run military hospitals where she was a Chief Surgeon. The most successful was the Endell Street Military Hospital in London, funded by the Royal Army Medical Corps and the only army hospital ever to be run and staffed entirely by women. Believing that a doctor had an obligation to take a lead in public affairs, Anderson continued campaigning for women's issues in the unlikely setting of Endell Street, ensuring that their activities remained in the public eye through constant press coverage. Anderson's achievement was that her work played no small part in expunging the stigma of the militant years in the eyes of the public and - more importantly - was largely instrumental in putting women doctors on equal terms with their male colleagues.

  3. Modified Anderson Model——Dynamics of Brittle Faulting

    NASA Astrophysics Data System (ADS)

    Tong, H.

    2014-12-01

    Anderson's model has been a basic theory of fault mechanical analysis in one century. However, because of the assumptions, there are some major limitations in Anderson model, and it does not account for frequently observed oblique slips, complicated fault cases in nature and the slips occurring on pre-existing planes of weakness. On the basis of Reactivation Tendency Analysis theory proposed by Tong and Yin (2011), we proposed Modified Anderson model and extended Anderson model from 1) homogeneous media to Inhomogeneous media with pre-existing weakness(es); 2) Andersonian stress state to arbitrary stress state; 3) transient activity trend analysis to fault formation and evolution, and verified with sandbox experiments and natural cases. With Modified Anderson model, we can predict 1) the sequence of fault formation; 2) fault orientations and distribution; 3) slip directions (dip slip, oblique-dip slip, oblique slip, oblique strike slip and strike sip) of different fault when the directions of principal stress, orientations and mechanical properties (cohesion and frictional coefficient) of pre-existing weakness(es) are given. The origin of the complicated fault systems in nature can be explained reasonably. There will be a wide applications for oil and gas exploration and development, coal mining, earthquake risk evaluation, etc.

  4. Polarons in π-Conjugated Polymers: Anderson or Landau?

    PubMed

    Barford, William; Marcus, Max; Tozer, Oliver Robert

    2016-02-04

    Using both analytical expressions and the density matrix renormalization group method, we study the fully quantized disordered Holstein model to investigate the localization of charges and excitons by vibrational or torsional modes-i.e., the formation of polarons-in conformationally disordered π-conjugated polymers. We identify two distinct mechanisms for polaron formation, namely Anderson localization via disorder (causing the formation of Anderson polarons) and self-localization by self-trapping via normal modes (causing the formation of Landau polarons). We identify the regimes where either description is more valid. The key distinction between Anderson and Landau polarons is that for the latter the particle wave function is a strong function of the normal coordinates, and hence the "vertical" and "relaxed" wave functions are different. This has theoretical and experimental consequences for Landau polarons. Theoretically, it means that the Condon approximation is not valid, and so care needs to be taken when evaluating transition rates. Experimentally, it means that the self-localization of the particle as a consequence of its coupling to the normal coordinates may lead to experimental observables, e.g., ultrafast fluorescence depolarization. We apply these ideas to poly(p-phenylenevinylene). We show that the high frequency C-C bond oscillation only causes Landau polarons for a very narrow parameter regime; generally we expect disorder to dominate and Anderson polarons to be a more applicable description. Similarly, for the low frequency torsional fluctuations we show that Anderson polarons are expected for realistic parameters.

  5. The M. D. Anderson proton therapy system.

    PubMed

    Smith, Alfred; Gillin, Michael; Bues, Martin; Zhu, X Ronald; Suzuki, Kazumichi; Mohan, Radhe; Woo, Shiao; Lee, Andrew; Komaki, Ritsko; Cox, James; Hiramoto, Kazuo; Akiyama, Hiroshi; Ishida, Takayuki; Sasaki, Toshie; Matsuda, Koji

    2009-09-01

    The purpose of this study is to describe the University of Texas M. D. Anderson proton therapy system (PTC-H) including the accelerator, beam transport, and treatment delivery systems, the functionality and clinical parameters for passive scattering and pencil beam scanning treatment modes, and the results of acceptance tests. The PTC-H has a synchrotron (70-250 MeV) and four treatment rooms. An overall control system manages the treatment, physics, and service modes of operation. An independent safety system ensures the safety of patients, staff, and equipment. Three treatment rooms have isocentric gantries and one room has two fixed horizontal beamlines, which include a large-field treatment nozzle, used primarily for prostate treatments, and a small-field treatment nozzle for ocular treatments. Two gantry treatment rooms and the fixed-beam treatment room have passive scattering nozzles. The third gantry has a pencil beam scanning nozzle for the delivery of intensity modulated proton treatments (IMPT) and single field uniform dose (SFUD) treatments. The PTC-H also has an experimental room with a fixed horizontal beamline and a passive scattering nozzle. The equipment described above was provided by Hitachi, Ltd. Treatment planning is performed using the Eclipse system from Varian Medical Systems and data management is handled by the MOSAIQ system from IMPAC Medical Systems, Inc. The large-field passive scattering nozzles use double scattering systems in which the first scatterers are physically integrated with the range modulation wheels. The proton beam is gated on the rotating range modulation wheels at gating angles designed to produce spread-out-Bragg peaks ranging in size from 2 to 16 g/cm2. Field sizes of up to 25 x 25 cm2 can be achieved with the double scattering system. The IMPT delivery technique is discrete spot scanning, which has a maximum field size of 30 x 30 cm2. Depth scanning is achieved by changing the energy extracted from the synchrotron

  6. The M. D. Anderson proton therapy system

    SciTech Connect

    Smith, Alfred; Gillin, Michael; Bues, Martin; Zhu, X. Ronald; Suzuki, Kazumichi; Mohan, Radhe; Woo, Shiao; Lee, Andrew; Komaki, Ritsko; Cox, James; Hiramoto, Kazuo; Akiyama, Hiroshi; Ishida, Takayuki; Sasaki, Toshie; Matsuda, Koji

    2009-09-15

    Purpose: The purpose of this study is to describe University of Texas M. D. Anderson proton therapy system (PTC-H) including the accelerator, beam transport, and treatment delivery systems, the functionality and clinical parameters for passive scattering and pencil beam scanning treatment modes, and the results of acceptance tests. Methods: The PTC-H has a synchrotron (70-250 MeV) and four treatment rooms. An overall control system manages the treatment, physics, and service modes of operation. An independent safety system ensures the safety of patients, staff, and equipment. Three treatment rooms have isocentric gantries and one room has two fixed horizontal beamlines, which include a large-field treatment nozzle, used primarily for prostate treatments, and a small-field treatment nozzle for ocular treatments. Two gantry treatment rooms and the fixed-beam treatment room have passive scattering nozzles. The third gantry has a pencil beam scanning nozzle for the delivery of intensity modulated proton treatments (IMPT) and single field uniform dose (SFUD) treatments. The PTC-H also has an experimental room with a fixed horizontal beamline and a passive scattering nozzle. The equipment described above was provided by Hitachi, Ltd. Treatment planning is performed using the Eclipse system from Varian Medical Systems and data management is handled by the MOSAIQ system from IMPAC Medical Systems, Inc. The large-field passive scattering nozzles use double scattering systems in which the first scatterers are physically integrated with the range modulation wheels. The proton beam is gated on the rotating range modulation wheels at gating angles designed to produce spread-out-Bragg peaks ranging in size from 2 to 16 g/cm{sup 2}. Field sizes of up to 25x25 cm{sup 2} can be achieved with the double scattering system. The IMPT delivery technique is discrete spot scanning, which has a maximum field size of 30x30 cm{sup 2}. Depth scanning is achieved by changing the energy

  7. Anderson wall and BLOCH oscillations in molecular rotation.

    PubMed

    Floß, Johannes; Averbukh, Ilya Sh

    2014-07-25

    We describe a universal behavior of linear molecules excited by a periodic train of short laser pulses under quantum resonance conditions. In a rigid rotor, the resonance causes an unlimited ballistic growth of the angular momentum. We show that the centrifugal distortion of rotating molecules eventually halts the growth, by causing Anderson localization beyond a critical value of the angular momentum--the Anderson wall. Its position solely depends on the molecular rotational constants and lies in the range of a few tens of ℏ. Below the wall, rotational excitation oscillates with the number of pulses due to a mechanism similar to Bloch oscillations in crystalline solids. We suggest optical experiments capable of observing the rotational Anderson wall and Bloch oscillations at near-ambient conditions with the help of existing laser technology.

  8. Anderson Transition for Classical Transport in Composite Materials

    NASA Astrophysics Data System (ADS)

    Murphy, N. Benjamin; Cherkaev, Elena; Golden, Kenneth M.

    2017-01-01

    The Anderson transition in solids and optics is a wave phenomenon where disorder induces localization of the wave functions. We find here that the hallmarks of the Anderson transition are exhibited by classical transport at a percolation threshold—without wave interference or scattering effects. As long range order or connectedness develops, the eigenvalue statistics of a key random matrix governing transport cross over toward universal statistics of the Gaussian orthogonal ensemble, and the field eigenvectors delocalize. The transition is examined in resistor networks, human bone, and sea ice structures.

  9. Dual-fermion approach to the Anderson-Hubbard model

    NASA Astrophysics Data System (ADS)

    Haase, P.; Yang, S.-X.; Pruschke, T.; Moreno, J.; Jarrell, M.

    2017-01-01

    We apply the recently developed dual-fermion algorithm for disordered interacting systems to the Anderson-Hubbard model. This algorithm is compared with dynamical cluster approximation calculations for a one-dimensional system to establish the quality of the approximation in comparison with an established cluster method. We continue with a three-dimensional (3D) system and look at the antiferromagnetic, Mott, and Anderson localization transitions. The dual-fermion approach leads to quantitative as well as qualitative improvement of the dynamical mean-field results, and it allows one to calculate the hysteresis in the double occupancy in 3D, taking into account nonlocal correlations.

  10. Anderson-Fabry cardiomyopathy: prevalence, pathophysiology, diagnosis and treatment.

    PubMed

    Putko, Brendan N; Wen, Kevin; Thompson, Richard B; Mullen, John; Shanks, Miriam; Yogasundaram, Haran; Sergi, Consolato; Oudit, Gavin Y

    2015-03-01

    Anderson-Fabry disease (AFD) is a lysosomal storage disease caused by the inappropriate accumulation of globotriaosylceramide in tissues due to a deficiency in the enzyme α-galactosidase A (α-Gal A). Anderson-Fabry cardiomyopathy is characterized by structural, valvular, vascular and conduction abnormalities, and is now the most common cause of mortality in patients with AFD. Large-scale metabolic and genetic screening studies have revealed AFD to be prevalent in populations of diverse ethnic origins, and the variant form of AFD represents an unrecognized health burden. Anderson-Fabry disease is an X-linked disorder, and genetic testing is critical for the diagnosis of AFD in women. Echocardiography with strain imaging and cardiac magnetic resonance imaging using late enhancement and T1 mapping are important imaging tools. The current therapy for AFD is enzyme replacement therapy (ERT), which can reverse or prevent AFD progression, while gene therapy and the use of molecular chaperones represent promising novel therapies for AFD. Anderson-Fabry cardiomyopathy is an important and potentially reversible cause of heart failure that involves LVH, increased susceptibility to arrhythmias and valvular regurgitation. Genetic testing and cardiac MRI are important diagnostic tools, and AFD cardiomyopathy is treatable if ERT is introduced early.

  11. Interpolation Processes in Object Perception: Reply to Anderson (2007)

    ERIC Educational Resources Information Center

    Kellman, Philip J.; Garrigan, Patrick; Shipley, Thomas F.; Keane, Brian P.

    2007-01-01

    P. J. Kellman, P. Garrigan, & T. F. Shipley presented a theory of 3-D interpolation in object perception. Along with results from many researchers, this work supports an emerging picture of how the visual system connects separate visible fragments to form objects. In his commentary, B. L. Anderson challenges parts of that view, especially the idea…

  12. An Anderson-like model of the QCD chiral transition

    NASA Astrophysics Data System (ADS)

    Giordano, Matteo; Kovács, Tamás G.; Pittler, Ferenc

    2016-06-01

    We study the problems of chiral symmetry breaking and eigenmode localisation in finite-temperature QCD by looking at the lattice Dirac operator as a random Hamiltonian. We recast the staggered Dirac operator into an unconventional three-dimensional Anderson Hamiltonian ("Dirac-Anderson Hamiltonian") carrying internal degrees of freedom, with disorder provided by the fluctuations of the gauge links. In this framework, we identify the features relevant to chiral symmetry restoration and localisation of the low-lying Dirac eigenmodes in the ordering of the local Polyakov lines, and in the related correlation between spatial links across time slices, thus tying the two phenomena to the deconfinement transition. We then build a toy model based on QCD and on the Dirac-Anderson approach, replacing the Polyakov lines with spin variables and simplifying the dynamics of the spatial gauge links, but preserving the above-mentioned relevant dynamical features. Our toy model successfully reproduces the main features of the QCD spectrum and of the Dirac eigenmodes concerning chiral symmetry breaking and localisation, both in the ordered (deconfined) and disordered (confined) phases. Moreover, it allows us to study separately the roles played in the two phenomena by the diagonal and the off-diagonal terms of the Dirac-Anderson Hamiltonian. Our results support our expectation that chiral symmetry restoration and localisation of the low modes are closely related, and that both are triggered by the deconfinement transition.

  13. CEBAS - MS Anderson works with three middeck payloads

    NASA Image and Video Library

    1998-03-03

    S89-E-5204 (25 Jan 1998) --- This Electronic Still Camera (ESC) image shows astronaut Michael P. Anderson, mission specialist, checking the Biotechnology Refrigerator (BTR) while transferring logistics, onboard the Space Shuttle Endeavour. This ESC view was taken on January 25, 1998, at 18:54:53 GMT.

  14. 9. VIEW OF SITE B FROM EAST END OF ANDERSON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW OF SITE B FROM EAST END OF ANDERSON WAY, FACING WEST (BUILDINGS 126, 128, 129, 130, and 131 ARE VISIBLE.) - Fort McPherson, World War II Station Hospital, Structures, Bordered by Hardee & Thorne Avenues & Howe Street, Atlanta, Fulton County, GA

  15. 10. VIEW OF SITE B FROM WEST END OF ANDERSON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW OF SITE B FROM WEST END OF ANDERSON WAY, FACING NORTHEAST (BUILDINGS 131, 130, 129, and 128 ARE VISIBLE.) - Fort McPherson, World War II Station Hospital, Structures, Bordered by Hardee & Thorne Avenues & Howe Street, Atlanta, Fulton County, GA

  16. Interpolation processes in object perception: reply to Anderson (2007).

    PubMed

    Kellman, Philip J; Garrigan, Patrick; Shipley, Thomas F; Keane, Brian P

    2007-04-01

    P. J. Kellman, P. Garrigan, & T. F. Shipley presented a theory of 3-D interpolation in object perception. Along with results from many researchers, this work supports an emerging picture of how the visual system connects separate visible fragments to form objects. In his commentary, B. L. Anderson challenges parts of that view, especially the idea of a common underlying interpolation component in modal and amodal completion (the identity hypothesis). Here the authors analyze Anderson's evidence and argue that he neither provides any reason to abandon the identity hypothesis nor offers a viable alternative theory. The authors offer demonstrations and analyses indicating that interpolated contours can appear modally despite absence of the luminance relations, occlusion geometry, and surface attachment that Anderson claims to be necessary. The authors elaborate crossing interpolations as key cases in which modal and amodal appearance must be consequences of interpolation. Finally, the authors dispute Anderson's assertion that vision researchers are misguided in using objective performance methods, and they argue that his challenges to relatability fail because contour and surface processes, as well as local and global influences, have been distinguished experimentally. (c) 2007 APA, all rights reserved.

  17. 75 FR 34170 - Plastic Omnium Automotive Exteriors, LLC, Anderson, SC; Plastic Omnium Automotive Exteriors, LLC...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-16

    ... Employment and Training Administration Plastic Omnium Automotive Exteriors, LLC, Anderson, SC; Plastic Omnium... Assistance on March 18, 2010, applicable to workers of Plastic Omnium Automotive Exteriors, LLC, Anderson... have occurred involving workers in support of the Anderson, South Carolina location of Plastic Omnium...

  18. Cavity quantum electrodynamics with Anderson-localized modes.

    PubMed

    Sapienza, Luca; Thyrrestrup, Henri; Stobbe, Søren; Garcia, Pedro David; Smolka, Stephan; Lodahl, Peter

    2010-03-12

    A major challenge in quantum optics and quantum information technology is to enhance the interaction between single photons and single quantum emitters. This requires highly engineered optical cavities that are inherently sensitive to fabrication imperfections. We have demonstrated a fundamentally different approach in which disorder is used as a resource rather than a nuisance. We generated strongly confined Anderson-localized cavity modes by deliberately adding disorder to photonic crystal waveguides. The emission rate of a semiconductor quantum dot embedded in the waveguide was enhanced by a factor of 15 on resonance with the Anderson-localized mode, and 94% of the emitted single photons coupled to the mode. Disordered photonic media thus provide an efficient platform for quantum electrodynamics, offering an approach to inherently disorder-robust quantum information devices.

  19. STS-107 Crew Interviews: Michael Anderson, Mission Specialist

    NASA Astrophysics Data System (ADS)

    2002-06-01

    STS-107 Mission Specialist 3 and Payload Commander Michael Anderson is seen during this preflight interview, where he gives a quick overview of the mission before answering questions about his inspiration to become an astronaut and his career path. He outlines his role in the mission in general, and specifically in conducting onboard science experiments. He discusses the following instruments and sets of experiments in detail: CM2 (Combustion Module 2), FREESTAR (Fast Reaction Enabling Science Technology and Research, MEIDEX (Mediterranean Israeli Dust Experiment) and MGM (Mechanics of Granular Materials). Anderson also mentions on-board activities and responsibilities during launch and reentry, mission training, and microgravity research. In addition, he touches on the dual work-shift nature of the mission, the use of crew members as research subjects including pre and postflight monitoring activities, the emphasis on crew safety during training and the value of international cooperation.

  20. Phase Shift of the Asymmetric Friedel-Anderson Impurity

    NASA Astrophysics Data System (ADS)

    Bergmann, Gerd

    2013-04-01

    The ground state of the asymmetric Friedel-Anderson (aFA) impurity is calculated within the FAIR (Friedel artificially inserted resonance) theory. Its properties are investigated by means of the fidelity with different Friedel impurities and by its Friedel oscillations. Friedel impurities with a specific phase shift δ at the Fermi level possess a finite fidelity with the aFA impurity. This phase shift δ determines other properties of the aFA impurity such as the amplitude and displacement of its Friedel oscillations. One can find the parameters of a Friedel impurity which coincides in its Friedel oscillations almost perfectly with the aFA impurity, thereby avoiding an Anderson orthogonality catastrophe.

  1. STS-107 Crew Interviews: Michael Anderson, Mission Specialist

    NASA Technical Reports Server (NTRS)

    2002-01-01

    STS-107 Mission Specialist 3 and Payload Commander Michael Anderson is seen during this preflight interview, where he gives a quick overview of the mission before answering questions about his inspiration to become an astronaut and his career path. He outlines his role in the mission in general, and specifically in conducting onboard science experiments. He discusses the following instruments and sets of experiments in detail: CM2 (Combustion Module 2), FREESTAR (Fast Reaction Enabling Science Technology and Research, MEIDEX (Mediterranean Israeli Dust Experiment) and MGM (Mechanics of Granular Materials). Anderson also mentions on-board activities and responsibilities during launch and reentry, mission training, and microgravity research. In addition, he touches on the dual work-shift nature of the mission, the use of crew members as research subjects including pre and postflight monitoring activities, the emphasis on crew safety during training and the value of international cooperation.

  2. Absence of Anderson localization in certain random lattices

    NASA Astrophysics Data System (ADS)

    Choi, Wonjun; Yin, Cheng; Hooper, Ian R.; Barnes, William L.; Bertolotti, Jacopo

    2017-08-01

    We report on the transition between an Anderson localized regime and a conductive regime in a one-dimensional microwave scattering system with correlated disorder. We show experimentally that when long-range correlations are introduced, in the form of a power-law spectral density with power larger than 2, the localization length becomes much bigger than the sample size and the transmission peaks typical of an Anderson localized system merge into a pass band. As other forms of long-range correlations are known to have the opposite effect, i.e., to enhance localization, our results show that care is needed when discussing the effects of correlations, as different kinds of long-range correlations can give rise to very different behavior.

  3. Anderson localization of graphene by helium ion irradiation

    SciTech Connect

    Naitou, Y.; Ogawa, S.

    2016-04-25

    Irradiation of a single-layer graphene (SLG) with accelerated helium ions (He{sup +}) controllably generates defect distributions, which create a charge carrier scattering source within the SLG. We report direct experimental observation of metal-insulator transition in SLG on SiO{sub 2}/Si substrates induced by Anderson localization. This transition was investigated using scanning capacitance microscopy by monitoring the He{sup +} dose conditions on the SLG. The experimental data show that a defect density of more than ∼1.2% induced Anderson localization. We also investigated the localization length by determining patterned placement of the defects and estimated the length to be several dozen nanometers. These findings provide valuable insight for patterning and designing graphene-based nanostructures using helium ion microscopy.

  4. Real-space renormalization group approach to the Anderson model

    NASA Astrophysics Data System (ADS)

    Campbell, Eamonn

    Many of the most interesting electronic behaviours currently being studied are associated with strong correlations. In addition, many of these materials are disordered either intrinsically or due to doping. Solving interacting systems exactly is extremely computationally expensive, and approximate techniques developed for strongly correlated systems are not easily adapted to include disorder. As a non-interacting disordered model, it makes sense to consider the Anderson model as a first step in developing an approximate method of solution to the interacting and disordered Anderson-Hubbard model. Our renormalization group (RG) approach is modeled on that proposed by Johri and Bhatt [23]. We found an error in their work which we have corrected in our procedure. After testing the execution of the RG, we benchmarked the density of states and inverse participation ratio results against exact diagonalization. Our approach is significantly faster than exact diagonalization and is most accurate in the limit of strong disorder.

  5. STS-107 Crew Interviews: Michael Anderson, Mission Specialist

    NASA Technical Reports Server (NTRS)

    2002-01-01

    STS-107 Mission Specialist 3 and Payload Commander Michael Anderson is seen during this preflight interview, where he gives a quick overview of the mission before answering questions about his inspiration to become an astronaut and his career path. He outlines his role in the mission in general, and specifically in conducting onboard science experiments. He discusses the following instruments and sets of experiments in detail: CM2 (Combustion Module 2), FREESTAR (Fast Reaction Enabling Science Technology and Research, MEIDEX (Mediterranean Israeli Dust Experiment) and MGM (Mechanics of Granular Materials). Anderson also mentions on-board activities and responsibilities during launch and reentry, mission training, and microgravity research. In addition, he touches on the dual work-shift nature of the mission, the use of crew members as research subjects including pre and postflight monitoring activities, the emphasis on crew safety during training and the value of international cooperation.

  6. Solar hot water system installed at Anderson, South Carolina

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A description is given of the solar energy hot water system installed in the Days Inns of America, Inc., at Anderson, South Carolina. The building is a low-rise, two-story 114-room motel. The solar system was designed to provide 40 percent of the total hot water demand. The collector is a flat plate, liquid with an area of 750 square feet. Operation of this system was begun in November 1977, and has performed flawlessly for one year.

  7. Ground-state properties of the periodic Anderson model

    NASA Technical Reports Server (NTRS)

    Blankenbecler, R.; Fulco, J. R.; Gill, W.; Scalapino, D. J.

    1987-01-01

    The ground-state energy, hybridization matrix element, local moment, and spin-density correlations of a one-dimensional, finite-chain, periodic, symmetric Anderson model are obtained by numerical simulations and compared with perturbation theory and strong-coupling results. It is found that the local f-electron spins are compensated by correlation with other f-electrons as well as band electrons leading to a nonmagnetic ground state.

  8. Markovian Anderson Model: Bounds for the Rate of Propagation

    NASA Astrophysics Data System (ADS)

    Tcheremchantsev, Serguei

    We consider the Anderson model in with potentials whose values at any site of the lattice are Markovian independent random functions of time. For solutions to the time-dependent Schrödinger equation we show under some conditions that with probability 1 where for d=1,2 and for .

  9. Anderson Mobility Gap Probed by Dynamic Coherent Backscattering.

    PubMed

    Cobus, L A; Skipetrov, S E; Aubry, A; van Tiggelen, B A; Derode, A; Page, J H

    2016-05-13

    We use dynamic coherent backscattering to study one of the Anderson mobility gaps in the vibrational spectrum of strongly disordered three-dimensional mesoglasses. Comparison of experimental results with the self-consistent theory of localization allows us to estimate the localization (correlation) length as a function of frequency in a wide spectral range covering bands of diffuse transport and a mobility gap delimited by two mobility edges. The results are corroborated by transmission measurements on one of our samples.

  10. Anderson works on the Nutrition Experiment during Expedition 15

    NASA Image and Video Library

    2007-06-25

    ISS015-E-13648 (25 June 2007) --- Astronaut Clayton Anderson, Expedition 15 flight engineer, works with test samples in the Human Research Facility 2 (HRF-2) Refrigerated Centrifuge as a part of the Nutritional Status Assessment (Nutrition) experiment in the Destiny laboratory of the International Space Station. The results of the Nutrition experiment will be used to better understand the time course effects of space flight on human physiology.

  11. On the Anderson localization conjecture in Dusty Plasma

    NASA Astrophysics Data System (ADS)

    Liaw, Constanze; Busse, Kyle; Matthews, Lorin; Hyde, Truell

    2015-11-01

    In 1958, Anderson suggested that sufficiently large impurities in a semi-conductor could lead to spatial localization of electrons. This idea unfolded into the field of Anderson Localization, one of the most fascinating phenomena in solid-state physics as it plays a major role in the conductive properties of imperfectly ordered materials. The Anderson Localization Conjecture claims that random disorder of any strength causes localization of electrons in the medium. The problem has proven to be highly non-trivial. Over the years the community has argued whether spatial localization occurs in 2D for small impurities. From a mathematical standpoint, the conjecture is still considered an open question. In 2013, Liaw challenged the commonly held assumption that localization holds in 2D by introducing a new mathematically more rigorous method to test for extended states, and applying it to the discrete random Schrödinger operator. One of the advantages of the underlying method is its versatility. It can be applied to any ordered system such as colloids, crystals, and atomic lattices. In a cross-disciplinary effort we merge this method with a numerical code used to simulate 2D physics systems, in preparation for experimentally testing the theory against complex plasma crystals.

  12. A Suitable Option for Gustilo and Anderson Grade III Injury

    PubMed Central

    Yang, Ronghua; Wang, Zhijun; Huang, Wenzhu; Zhao, Yuhuan; Xu, Lusheng; Yu, Shaobin

    2016-01-01

    Background The management of Gustilo and Anderson grade III injury remains difficult, particularly due to the incidence of wound infections, delayed fracture union, and traumatic extremity amputation. However, little data is available on delayed skin graft or flap reconstructions of Gustilo grade III injury, especially using new technologies of wound coverage, such as vacuum sealing drainage (VSD) combined with limited internal and/or external fixation. Material/Methods Between June 2008 and May 2013, we performed the VSD technique combined with limited internal and/or external fixation on 38 patients (22 males and 16 females, with a mean age of 36.5 years) with Gustilo and Anderson grade III injury. VSD was regularly changed and delayed skin grafts or flaps were used to cover the defect. Two patients were lost to follow-up, and the remaining 36 were available for evaluation. The complications, wound healing, infections, and bony union were assessed for a mean duration of 2.5 years (range, 1–4 years). Results Complications were seen in 5 of the 36 cases: 2 cases had infection alone, 1 case had delayed union or nonunion, 1 case had infection and delayed union, and 1 case had wound necrosis, infection, and nonunion. VSD was regularly changed 2–6 times. Morphological appearance and functional recovery were satisfactory in all cases. Conclusions Using VSD before skin grafts or flaps coverage, combined with limited internal and/or external fixation, is a suitable option for Gustilo and Anderson grade III injury. PMID:27564219

  13. Topological Anderson insulator induced by inter-cell hopping disorder

    SciTech Connect

    Lv, Shu-Hui; Song, Juntao Li, Yu-Xian

    2013-11-14

    We have studied in detail the influence of same-orbit and different-orbit hopping disorders in HgTe/CdTe quantum wells. Intriguingly, similar to the behavior of the on-site Anderson disorder, a phase transition from a topologically trivial phase to a topological phase is induced at a proper strength of the same-orbit hopping disorder. For different-orbit hopping disorder, however, the phase transition does not occur. The results have been analytically verified by using effective medium theory. A consistent conclusion can be obtained by comparing phase diagrams, conductance, and conductance fluctuations. In addition, the influence of Rashba spin-orbit interaction (RSOI) on the system has been studied for different types of disorder, and the RSOI shows different influence on topological phase at different disorders. The topological phase induced by same-orbit hopping disorder is more robust against the RSOI than that induced by on-site Anderson disorder. For different-orbit hopping disorder, no matter whether the RSOI is included or not, the phase transition does not occur. The results indicate, whether or not the topological Anderson insulator can be observed depends on a competition between the different types of the disorder as well as the strength of the RSOI in a system.

  14. Super-diffusion in optical realizations of Anderson localization

    NASA Astrophysics Data System (ADS)

    Krivolapov, Yevgeny; Levi, Liad; Fishman, Shmuel; Segev, Mordechai; Wilkinson, Michael

    2012-04-01

    We discuss the dynamics of particles in one dimension in potentials that are random in both space and time. The results are applied to recent optics experiments on Anderson localization, in which the transverse spreading of a beam is suppressed by random fluctuations in the refractive index. If the refractive index fluctuates along the direction of the paraxial propagation of the beam, the localization is destroyed. We analyze this broken localization in terms of the spectral decomposition of the potential. When the potential has a discrete spectrum, the spread is controlled by the overlap of Chirikov resonances in phase space. As the number of Fourier components is increased, the resonances merge into a continuum, which is described by a Fokker-Planck equation. We express the diffusion coefficient in terms of the spectral intensity of the potential. For a general class of potentials that are commonly used in optics, the solutions to the Fokker-Planck equation exhibit anomalous diffusion in phase space, implying that when Anderson localization is broken by temporal fluctuations of the potential, the result is transport at a rate similar to a ballistic one or even faster. For a class of potentials which arise in some existing realizations of Anderson localization, atypical behavior is found.

  15. Centrifugal Distortion Causes Anderson Localization in Laser Kicked Molecules

    NASA Astrophysics Data System (ADS)

    Floss, Johannes; Averbukh, Ilya Sh.

    2014-05-01

    The periodically kicked 2D rotor is a textbook model in nonlinear dynamics. The classical kicked rotor can exhibit truly chaotic motion, whilst in the quantum regime this chaotic motion is suppressed by a mechanism similar to Anderson Localization. Up to now, these effects have been mainly observed in an atom optics analogue of a quantum rotor: cold atoms in a standing light wave. We demonstrate that common linear molecules (like N2, O2, CO2, ...), kicked by a train of short linearly polarized laser pulses, can exhibit a new mechanism for dynamical Anderson Localization due to their non-rigidity. When the pulses are separated by the rotational revival time trev = πℏ / B , the angular momentum J grows ballistically (Quantum Resonance). We show that, due to the centrifugal distortion of fast spinning molecules, above some critical value J =Jcr the Quantum Resonance is suppressed via the mechanism of Anderson Localization. This leads to a non-sinusoidal oscillation of the angular momentum distribution, which may be experimentally observed even at ambient conditions by using current techniques for laser molecular alignment.

  16. La place de la double arthrodèse dans la prise en charge du pied bot varus équin invétéré

    PubMed Central

    Atarraf, Karima; Arroud, Mounir; Chater, Lamiae; Afifi, My Abderrahmane

    2014-01-01

    La prise en charge du pied bot varus équin invétéré ( PBVEI) pose d’énormes problèmes thérapeutiques. La double arthrodèse sous-talienne et médio-tarsienne longtemps considérée comme la solution de sécurité pour ces déformations est encore couramment utilisée. Nous rapportons une série de 13 enfants opérés pour un pied bot varus équin invétérés (16 pieds) par Arthrodèse sous-talienne et médio tarsienne réalisée au service d'orthopédie pédiatrique du CHU Hassan II; de Fès au Maroc sur une période de 4 ans; étalée de janvier 2009 à décembre 2012. L’âge moyen de nos patients était de 12,6 ans avec prédominance féminine. L'origine congénitale était retrouvée chez 10 patients. L'atteinte était gauche chez 8 patients avec une localisation bilatérale chez 3 patients. La radiographie standard du pied de face et de profil a révélée une divergence talo-calcanéenne qui variait entre 5 et 20°, l'angle talus-1er métatarsien entre 20 et 40° (avec une moyenne de 28°) et l'angle calcanéus-5ème métatarsien entre 15° et 45° (avec une moyenne de 30°). Tous les patients ont bénéficiés d'une arthrodèse sous-talienne et médio tarsienne. Les résultats étaient satisfaisants dans 98% des cas. Le pied était plantigrade dans 9 cas, le varus de l'arrière pied persistait dans 4 pieds alors que l’équin et le varus de l'avant pied étaient notés chez 2 cas. La double arthrodèse est l'intervention idéale pour stabiliser et corriger les déformations rencontrées dans le PBVE invétéré, elle assure totalement le verrouillage du couple de torsion. Elle permet outre une correction des diverses déformations et une ré-axation de l'arrière-pied dans les 3 plans de l'espace. PMID:25829977

  17. Transversal Anderson localization of sound in acoustic waveguide arrays.

    PubMed

    Ye, Yangtao; Ke, Manzhu; Feng, Junheng; Wang, Mudi; Qiu, Chunyin; Liu, Zhengyou

    2015-04-22

    We present designs of one-dimensional acoustic waveguide arrays and investigate wave propagation inside. Under the condition of single identical waveguide mode and weak coupling, the acoustic wave motion in waveguide arrays can be modeled with a discrete mode-coupling theory. The coupling constants can be retrieved from simulations or experiments as the function of neighboring waveguide separations. Sound injected into periodic arrays gives rise to the discrete diffraction, exhibiting ballistic or extended transport in transversal direction. But sound injected into randomized waveguide arrays readily leads to Anderson localization transversally. The experimental results show good agreement with simulations and theoretical predictions.

  18. Note: Work function change measurement via improved Anderson method.

    PubMed

    Sabik, A; Gołek, F; Antczak, G

    2015-05-01

    We propose the modification to the Anderson method of work function change (Δϕ) measurements. In this technique, the kinetic energy of the probing electrons is already low enough for non-destructive investigation of delicate molecular systems. However, in our implementation, all electrodes including filament of the electron gun are polarized positively. As a consequence, electron bombardment of any elements of experimental system is eliminated. Our modification improves cleanliness of the ultra-high vacuum system. As an illustration of the solution capabilities, we present Δϕ of the Ag(100) surface induced by cobalt phthalocyanine layers.

  19. Probability Density Function at the 3D Anderson Transition

    NASA Astrophysics Data System (ADS)

    Rodriguez, Alberto; Vasquez, Louella J.; Roemer, Rudolf

    2009-03-01

    The probability density function (PDF) for the wavefunction amplitudes is studied at the metal-insulator transition of the 3D Anderson model, for very large systems up to L^3=240^3. The implications of the multifractal nature of the state upon the PDF are presented in detail. A formal expression between the PDF and the singularity spectrum f(α) is given. The PDF can be easily used to carry out a numerical multifractal analysis and it appears as a valid alternative to the more usual approach based on the scaling law of the general inverse participation rations.

  20. Note: Work function change measurement via improved Anderson method

    SciTech Connect

    Sabik, A. Gołek, F.; Antczak, G.

    2015-05-15

    We propose the modification to the Anderson method of work function change (Δϕ) measurements. In this technique, the kinetic energy of the probing electrons is already low enough for non-destructive investigation of delicate molecular systems. However, in our implementation, all electrodes including filament of the electron gun are polarized positively. As a consequence, electron bombardment of any elements of experimental system is eliminated. Our modification improves cleanliness of the ultra-high vacuum system. As an illustration of the solution capabilities, we present Δϕ of the Ag(100) surface induced by cobalt phthalocyanine layers.

  1. The optical Anderson localization in three-dimensional percolation system

    NASA Astrophysics Data System (ADS)

    Burlak, G.; Martinez-Sánchez, E.

    2017-03-01

    We study the optical Anderson localization associated with the properties of three-dimensional (3D) disordered percolation system, where the percolating clusters are filled by active media composed by light noncoherent emitters. In such a non-uniformly spatial structure the radiating and scattering of field occur by incoherent way. We numerically study 3D field structures where the wave localization takes place and propose the criterion of field localization based on conception of a mean photon free path in such system. The analysis of a mean free path and the Inverse participation ratio (IPR) shows that the localization arises closely to the threshold of 3D percolation phase transition.

  2. Giant charge relaxation resistance in the Anderson model.

    PubMed

    Filippone, Michele; Le Hur, Karyn; Mora, Christophe

    2011-10-21

    We investigate the dynamical charge response of the Anderson model viewed as a quantum RC circuit. Applying a low-energy effective Fermi liquid theory, a generalized Korringa-Shiba formula is derived at zero temperature, and the charge relaxation resistance is expressed solely in terms of static susceptibilities which are accessible by Bethe ansatz. We identify a giant charge relaxation resistance at intermediate magnetic fields related to the destruction of the Kondo singlet. The scaling properties of this peak are computed analytically in the Kondo regime. We also show that the resistance peak fades away at the particle-hole symmetric point.

  3. Applying a southern solvent: an interview with Warwick Anderson.

    PubMed

    Anderson, Warwick; Cueto, Marcos; Santos, Ricardo Ventura

    2016-12-01

    An interview by the editor and a member of the scientific board of História, Ciências, Saúde - Manguinhos with Warwick Anderson, a leading historian of science and race from Australia. He talks about his training, positions he held at US universities, his publications, and his research at the University of Sydney. He discusses his current concern with the circulation of racial knowledge and biological materials as well as with the construction of networks of racial studies in the global south during the twentieth century. He also challenges the traditional historiography of science, which conventionally has been told from a Eurocentric perspective.

  4. Probing Anderson localization using the dynamics of a qubit

    NASA Astrophysics Data System (ADS)

    Eleuch, Hichem; Hilke, Michael; MacKenzie, Richard

    2017-06-01

    Anderson localization is a consequence of coherent interference of multiple scattering events in the presence of disorder, which leads to an exponential suppression of the transmission. The decay of the transmission is typically probed at a given energy or frequency. Here we show that this decay affects the dynamics of a qubit coupled to the disordered system and we express the relaxation rate of the qubit in terms of the localization properties. Conversely, adding static disorder to a channel coupled to a qubit will reduce the decoherence rate of the qubit. Hence, when designing electrodes that couple to qubits, it is possible to improve their performance by adding impurities to the channel.

  5. Price-Anderson Nuclear Safety Enforcement Program. 1996 Annual report

    SciTech Connect

    1996-01-01

    This first annual report on DOE`s Price Anderson Amendments Act enforcement program covers the activities, accomplishments, and planning for calendar year 1996. It also includes the infrastructure development activities of 1995. It encompasses the activities of the headquarters` Office of Enforcement in the Office of Environment, Safety and Health (EH) and Investigation and the coordinators and technical advisors in DOE`s Field and Program Offices and other EH Offices. This report includes an overview of the enforcement program; noncompliances, investigations, and enforcement actions; summary of significant enforcement actions; examples where enforcement action was deferred; and changes and improvements to the program.

  6. Anderson Localization of Ultracold Atoms: Where is the Mobility Edge?

    NASA Astrophysics Data System (ADS)

    Pasek, Michael; Orso, Giuliano; Delande, Dominique

    2017-04-01

    Recent experiments in noninteracting ultracold atoms in three-dimensional speckle potentials have yielded conflicting results regarding the so-called mobility edge, i.e., the energy threshold separating Anderson localized from diffusive states. At the same time, there are theoretical indications that most experimental data overestimate this critical energy, sometimes by a large amount. Using extensive numerical simulations, we show that the effect of anisotropy in the spatial correlations of realistic disorder configurations alone is not sufficient to explain the experimental data. In particular, we find that the mobility edge obeys a universal scaling behavior, independently of the speckle geometry.

  7. The S=1 Underscreened Anderson Lattice model for Uranium compounds

    NASA Astrophysics Data System (ADS)

    Thomas, C.; Simões, A. S. R.; Iglesias, J. R.; Lacroix, C.; Perkins, N. B.; Coqblin, B.

    2011-01-01

    Magnetic properties of uranium and neptunium compounds showing coexistence of the Kondo effect and ferromagnetic order are investigated within the degenerate Anderson Lattice Hamiltonian, describing a 5f2 electronic configuration with S = 1 spins. Through the Schrieffer-Wolff transformation, both an exchange Kondo interaction for the S = 1 f-spins and an effective f-band term are obtained, allowing to describe the coexistence of Kondo effect and ferromagnetic ordering and a weak delocalization of the 5f-electrons. We calculate the Kondo and Curie temperatures and we can account for the pressure dependence of the Curie temperature of UTe.

  8. Quantum Criticality of Quasi-One-Dimensional Topological Anderson Insulators

    NASA Astrophysics Data System (ADS)

    Altland, Alexander; Bagrets, Dmitry; Fritz, Lars; Kamenev, Alex; Schmiedt, Hanno

    2014-05-01

    We present an analytic theory of quantum criticality in the quasi-one-dimensional topological Anderson insulators of class AIII and BDI. We describe the systems in terms of two parameters (g, χ) representing localization and topological properties, respectively. Surfaces of half-integer valued χ define phase boundaries between distinct topological sectors. Upon increasing system size, the two parameters exhibit flow similar to the celebrated two-parameter flow describing the class A quantum Hall insulator. However, unlike the quantum Hall system, an exact analytical description of the entire phase diagram can be given. We check the quantitative validity of our theory by comparison to numerical transfer matrix computations.

  9. STS-118 Astronauts Rick Mastracchio and Clay Anderson Perform EVA

    NASA Technical Reports Server (NTRS)

    2007-01-01

    As the construction continued on the International Space Station (ISS), STS-118 astronaut and mission specialist Rick Mastracchio was anchored on the foot restraint of the Canadarm2 as he participated in the third session of Extra Vehicular Activity (EVA) for the mission. Assisting Mastracchio was Expedition 15 flight engineer Clay Anderson (out of frame). During the 5 hour, 28 minute space walk, the two relocated the S-band Antenna Sub-Assembly from the Port 6 (P6) truss to the Port 1 (P1) truss, installed a new transponder on P1 and retrieved the P6 transponder.

  10. STS-107 Payload Commander Michael Anderson suits up for TCDT

    NASA Technical Reports Server (NTRS)

    2002-01-01

    KENNEDY SPACE CENTER, FLA. - STS-107 Payload Commander Michael Anderson smiles as he undergoes suit check prior to Terminal Countdown Demonstration Test activities, which include a simulated launch countdown at the pad. STS-107 is a mission devoted to research and will include more than 80 experiments that will study Earth and space science, advanced technology development, and astronaut health and safety. Launch is planned for Jan. 16, 2003, between 10 a.m. and 2 p.m. EST aboard Space Shuttle Columbia. .

  11. Remembering Joan (Jan) Mary Anderson (1932-2015).

    PubMed

    Chow, Wah Soon; Horton, Peter; Barrett, Martin; Osmond, Charles Barry

    2016-08-01

    Joan Mary Anderson, known to most people as Jan, was born on May 12, 1932 in Dunedin, New Zealand. She died on August 28, 2015 in Canberra, Australia. To celebrate her life, we present here a brief biography, some comments on her discoveries in photosynthesis during a career spanning more than half a century, and reminiscences from family and friends. We remember this wonderful person who had an unflagging curiosity, creative ability to think laterally, enthusiasm, passion, generosity and love of color and culture.

  12. Collective Kondo effect in the Anderson-Hubbard lattice

    NASA Astrophysics Data System (ADS)

    Fazekas, P.; Itai, K.

    1997-02-01

    The periodic Anderson model is extended by switching on a Hubbard U for the conduction electrons. We use the Gutzwiller variational method to study the nearly integral valent limit. The lattice Kondo energy contains the U-dependent chemical potential of the Hubbard subsystem in the exponent, and the correlation-induced band narrowing in the prefactor. Both effects tend to suppress the Kondo scale, which can be understood to result from the blocking of hybridization. At half-filling, we find a Brinkman-Rice-type transition from a Kondo insulator to a Mott insulator.

  13. Recurrent Scattering and Memory Effect at the Anderson Localization Transition

    NASA Astrophysics Data System (ADS)

    Aubry, A.; Cobus, L. A.; Skipetrov, S. E.; van Tiggelen, B. A.; Derode, A.; Page, J. H.

    2014-01-01

    We report on ultrasonic measurements of the propagation operator in a strongly scattering mesoglass. The backscattered field is shown to display a deterministic spatial coherence due to a remarkably large memory effect induced by long recurrent trajectories. Investigation of the recurrent scattering contribution directly yields the probability for a wave to come back close to its starting spot. The decay of this quantity with time is shown to change dramatically near the Anderson localization transition. The singular value decomposition of the propagation operator reveals the dominance of very intense recurrent scattering paths near the mobility edge.

  14. Kubo-Anderson Mixing in the Turbulent Boundary Layer

    NASA Astrophysics Data System (ADS)

    Dekker, H.; de Leeuw, G.; Brink, A. Maassen Van Den

    A novel ab initio analysis of the Reynolds stress is presented in order to model non-local turbulence transport. The theory involves a sample path space and a stochastic hypothesis. A scaling relation maps the path space onto the boundary layer. Analytical sampling rates are shown to model mixing by exchange. Nonlocal mixing involves a scaling exponent ɛ≈0.58 (ɛ→∞ in the diffusion limit). The resulting transport equation represents a nondiffusive (Kubo-Anderson or kangaroo) type stochastic process.

  15. Anderson acceleration and application to the three-temperature energy equations

    NASA Astrophysics Data System (ADS)

    An, Hengbin; Jia, Xiaowei; Walker, Homer F.

    2017-10-01

    The Anderson acceleration method is an algorithm for accelerating the convergence of fixed-point iterations, including the Picard method. Anderson acceleration was first proposed in 1965 and, for some years, has been used successfully to accelerate the convergence of self-consistent field iterations in electronic-structure computations. Recently, the method has attracted growing attention in other application areas and among numerical analysts. Compared with a Newton-like method, an advantage of Anderson acceleration is that there is no need to form the Jacobian matrix. Thus the method is easy to implement. In this paper, an Anderson-accelerated Picard method is employed to solve the three-temperature energy equations, which are a type of strong nonlinear radiation-diffusion equations. Two strategies are used to improve the robustness of the Anderson acceleration method. One strategy is to adjust the iterates when necessary to satisfy the physical constraint. Another strategy is to monitor and, if necessary, reduce the matrix condition number of the least-squares problem in the Anderson-acceleration implementation so that numerical stability can be guaranteed. Numerical results show that the Anderson-accelerated Picard method can solve the three-temperature energy equations efficiently. Compared with the Picard method without acceleration, Anderson acceleration can reduce the number of iterations by at least half. A comparison between a Jacobian-free Newton-Krylov method, the Picard method, and the Anderson-accelerated Picard method is conducted in this paper.

  16. Stimulus-response coupling in human platelets. Changes evoked by platelet-activating factor in cytoplasmic free calcium monitored with the fluorescent calcium indicator quin2.

    PubMed Central

    Hallam, T J; Sanchez, A; Rink, T J

    1984-01-01

    The role of changes in cytoplasmic free calcium, [Ca2+]i, in the responses to platelet-activating factor (PAF) was studied in human platelets loaded with the fluorescent calcium indicator, quin2. In the presence of 1 mM external calcium, PAF raised [Ca2+]i 8-10-fold in a few seconds to peak near 1 microM. [Ca2+]i then declined over several minutes towards the basal level. In the absence of external calcium there was a much smaller increase in [Ca2+]i of similar pattern. These findings suggest that PAF increases [Ca2+]i partly by discharge of internal Ca2+, but mainly by stimulated influx. Blockade of cyclo-oxygenase with aspirin only slightly reduced the [Ca2+]i changes, indicating that thromboxane A2 is not a major mediator of the calcium movements. In control conditions PAF could stimulate shape-change, aggregation and secretion. Aggregation and secretion were roughly halved by blockade of cyclo-oxygenase. Shape-change and secretion still occurred under conditions where the [Ca2+]i rise was small or suppressed, indicating a role for intracellular activators other than Ca2+. The possible involvement of products of phosphoinositide breakdown is discussed. PMID:6426464

  17. Anderson localization and ergodicity on random regular graphs

    NASA Astrophysics Data System (ADS)

    Tikhonov, K. Â. S.; Mirlin, A. Â. D.; Skvortsov, M. Â. A.

    2016-12-01

    A numerical study of Anderson transition on random regular graphs (RRGs) with diagonal disorder is performed. The problem can be described as a tight-binding model on a lattice with N sites that is locally a tree with constant connectivity. In a certain sense, the RRG ensemble can be seen as an infinite-dimensional (d →∞ ) cousin of the Anderson model in d dimensions. We focus on the delocalized side of the transition and stress the importance of finite-size effects. We show that the data can be interpreted in terms of the finite-size crossover from a small (N ≪Nc ) to a large (N ≫Nc ) system, where Nc is the correlation volume diverging exponentially at the transition. A distinct feature of this crossover is a nonmonotonicity of the spectral and wave-function statistics, which is related to properties of the critical phase in the studied model and renders the finite-size analysis highly nontrivial. Our results support an analytical prediction that states in the delocalized phase (and at N ≫Nc ) are ergodic in the sense that their inverse participation ratio scales as 1 /N .

  18. Quantum non-Markovianity induced by Anderson localization

    PubMed Central

    Lorenzo, Salvatore; Lombardo, Federico; Ciccarello, Francesco; Palma, G. Massimo

    2017-01-01

    As discovered by P. W. Anderson, excitations do not propagate freely in a disordered lattice, but, due to destructive interference, they localise. As a consequence, when an atom interacts with a disordered lattice, one indeed observes a non-trivial excitation exchange between atom and lattice. Such non-trivial atomic dynamics will in general be characterised also by a non-trivial quantum information backflow, a clear signature of non-Markovian dynamics. To investigate the above scenario, we consider a quantum emitter, or atom, weakly coupled to a uniform coupled-cavity array (CCA). If initially excited, in the absence of disorder, the emitter undergoes a Markovian spontaneous emission by releasing all its excitation into the CCA (initially in its vacuum state). By introducing static disorder in the CCA the field normal modes become Anderson-localized, giving rise to a non-Markovian atomic dynamics. We show the existence of a functional relationship between a rigorous measure of quantum non-Markovianity and the CCA localization. We furthermore show that the average non-Markovianity of the atomic dynamics is well-described by a phenomenological model in which the atom is coupled, at the same time, to a single mode and to a standard - Markovian - dissipative bath. PMID:28205542

  19. Anderson localization and Mott insulator phase in the time domain

    PubMed Central

    Sacha, Krzysztof

    2015-01-01

    Particles in space periodic potentials constitute standard models for investigation of crystalline phenomena in solid state physics. Time periodicity of periodically driven systems is a close analogue of space periodicity of solid state crystals. There is an intriguing question if solid state phenomena can be observed in the time domain. Here we show that wave-packets localized on resonant classical trajectories of periodically driven systems are ideal elements to realize Anderson localization or Mott insulator phase in the time domain. Uniform superpositions of the wave-packets form stationary states of a periodically driven particle. However, an additional perturbation that fluctuates in time results in disorder in time and Anderson localization effects emerge. Switching to many-particle systems we observe that depending on how strong particle interactions are, stationary states can be Bose-Einstein condensates or single Fock states where definite numbers of particles occupy the periodically evolving wave-packets. Our study shows that non-trivial crystal-like phenomena can be observed in the time domain. PMID:26074169

  20. Quantum non-Markovianity induced by Anderson localization

    NASA Astrophysics Data System (ADS)

    Lorenzo, Salvatore; Lombardo, Federico; Ciccarello, Francesco; Palma, G. Massimo

    2017-02-01

    As discovered by P. W. Anderson, excitations do not propagate freely in a disordered lattice, but, due to destructive interference, they localise. As a consequence, when an atom interacts with a disordered lattice, one indeed observes a non-trivial excitation exchange between atom and lattice. Such non-trivial atomic dynamics will in general be characterised also by a non-trivial quantum information backflow, a clear signature of non-Markovian dynamics. To investigate the above scenario, we consider a quantum emitter, or atom, weakly coupled to a uniform coupled-cavity array (CCA). If initially excited, in the absence of disorder, the emitter undergoes a Markovian spontaneous emission by releasing all its excitation into the CCA (initially in its vacuum state). By introducing static disorder in the CCA the field normal modes become Anderson-localized, giving rise to a non-Markovian atomic dynamics. We show the existence of a functional relationship between a rigorous measure of quantum non-Markovianity and the CCA localization. We furthermore show that the average non-Markovianity of the atomic dynamics is well-described by a phenomenological model in which the atom is coupled, at the same time, to a single mode and to a standard - Markovian - dissipative bath.

  1. Integrals of motion for one-dimensional Anderson localized systems

    NASA Astrophysics Data System (ADS)

    Modak, Ranjan; Mukerjee, Subroto; Yuzbashyan, Emil A.; Shastry, B. Sriram

    2016-03-01

    Anderson localization is known to be inevitable in one-dimension for generic disordered models. Since localization leads to Poissonian energy level statistics, we ask if localized systems possess ‘additional’ integrals of motion as well, so as to enhance the analogy with quantum integrable systems. We answer this in the affirmative in the present work. We construct a set of nontrivial integrals of motion for Anderson localized models, in terms of the original creation and annihilation operators. These are found as a power series in the hopping parameter. The recently found Type-1 Hamiltonians, which are known to be quantum integrable in a precise sense, motivate our construction. We note that these models can be viewed as disordered electron models with infinite-range hopping, where a similar series truncates at the linear order. We show that despite the infinite range hopping, all states but one are localized. We also study the conservation laws for the disorder free Aubry-Andre model, where the states are either localized or extended, depending on the strength of a coupling constant. We formulate a specific procedure for averaging over disorder, in order to examine the convergence of the power series. Using this procedure in the Aubry-Andre model, we show that integrals of motion given by our construction are well-defined in localized phase, but not so in the extended phase. Finally, we also obtain the integrals of motion for a model with interactions to lowest order in the interaction.

  2. Quantum non-Markovianity induced by Anderson localization.

    PubMed

    Lorenzo, Salvatore; Lombardo, Federico; Ciccarello, Francesco; Palma, G Massimo

    2017-02-16

    As discovered by P. W. Anderson, excitations do not propagate freely in a disordered lattice, but, due to destructive interference, they localise. As a consequence, when an atom interacts with a disordered lattice, one indeed observes a non-trivial excitation exchange between atom and lattice. Such non-trivial atomic dynamics will in general be characterised also by a non-trivial quantum information backflow, a clear signature of non-Markovian dynamics. To investigate the above scenario, we consider a quantum emitter, or atom, weakly coupled to a uniform coupled-cavity array (CCA). If initially excited, in the absence of disorder, the emitter undergoes a Markovian spontaneous emission by releasing all its excitation into the CCA (initially in its vacuum state). By introducing static disorder in the CCA the field normal modes become Anderson-localized, giving rise to a non-Markovian atomic dynamics. We show the existence of a functional relationship between a rigorous measure of quantum non-Markovianity and the CCA localization. We furthermore show that the average non-Markovianity of the atomic dynamics is well-described by a phenomenological model in which the atom is coupled, at the same time, to a single mode and to a standard - Markovian - dissipative bath.

  3. Integrals of motion for one-dimensional Anderson localized systems

    SciTech Connect

    Modak, Ranjan; Mukerjee, Subroto; Yuzbashyan, Emil A.; Shastry, B. Sriram

    2016-03-02

    Anderson localization is known to be inevitable in one-dimension for generic disordered models. Since localization leads to Poissonian energy level statistics, we ask if localized systems possess ‘additional’ integrals of motion as well, so as to enhance the analogy with quantum integrable systems. Weanswer this in the affirmative in the present work. We construct a set of nontrivial integrals of motion for Anderson localized models, in terms of the original creation and annihilation operators. These are found as a power series in the hopping parameter. The recently found Type-1 Hamiltonians, which are known to be quantum integrable in a precise sense, motivate our construction.Wenote that these models can be viewed as disordered electron models with infinite-range hopping, where a similar series truncates at the linear order.Weshow that despite the infinite range hopping, all states but one are localized.Wealso study the conservation laws for the disorder free Aubry–Andre model, where the states are either localized or extended, depending on the strength of a coupling constant.Weformulate a specific procedure for averaging over disorder, in order to examine the convergence of the power series. Using this procedure in the Aubry–Andre model, we show that integrals of motion given by our construction are well-defined in localized phase, but not so in the extended phase. Lastly, we also obtain the integrals of motion for a model with interactions to lowest order in the interaction.

  4. Reply. [to the comment by Anderson et al. (1993)

    NASA Technical Reports Server (NTRS)

    Hegg, Dean A.; Ferek, Ronald G.; Hobbs, Peter V.

    1994-01-01

    While Hegg et al. (1993) accepts the criticism of Anderson et al. (1994) in principle, this involves the adoption of an aerosol composition model and the model that they propose to reconcile these observations with the assertion of Charlson et al. (1992) does not agree with many observations, particularly those made over the North Atlantic Ocean. Although the use of a gain factor (i.e. the partial derivative of aerosol mass with respect to the sulfate ion), proposed by Anderson et al., may be valid for particular cases where a proposed composition model really reflects the actual aerosol composition, this procedure is considered questionable in general. The use of sulfate as a tracer for nonsulfate aerosol mass is questionable, because in the present authors' data set, sulfate averaged only about 26% of the dry aerosol mass. The ammonium mass associated with sulfate mass is not analogous to that betwen the oxygen mass and sulfur mass in the sulfate ion. Strong chemical bonds are present between sulfur and oxygen in sulfate, whereas ammonium and sulfate in haze droplets are ions in solution that may or may not be associated with one another. Thus, there is no reason to assume that sulfate will act as a reliable tracer of ammonium mass. Hegg et al. expresses the view that their approach used for estimating sulfate light scattering efficiency is appropriate for the current level of understanding of atmospheric aerosols.

  5. Award for Distinguished Scientific Early Career Contributions to Psychology: Adam K. Anderson

    ERIC Educational Resources Information Center

    American Psychologist, 2009

    2009-01-01

    Adam K. Anderson, recipient of the Award for Distinguished Scientific Early Career Contributions to Psychology, is cited for his outstanding contribution to understanding the representation of emotion and its influence on cognition. By combining psychological and neuroscience techniques with rigorous and creative experimental designs, Anderson has…

  6. Award for Distinguished Scientific Early Career Contributions to Psychology: Adam K. Anderson

    ERIC Educational Resources Information Center

    American Psychologist, 2009

    2009-01-01

    Adam K. Anderson, recipient of the Award for Distinguished Scientific Early Career Contributions to Psychology, is cited for his outstanding contribution to understanding the representation of emotion and its influence on cognition. By combining psychological and neuroscience techniques with rigorous and creative experimental designs, Anderson has…

  7. Topological Anderson insulators in systems without time-reversal symmetry

    NASA Astrophysics Data System (ADS)

    Su, Ying; Avishai, Y.; Wang, X. R.

    2016-06-01

    Occurrence of the topological Anderson insulator (TAI) in a HgTe quantum well suggests that when time-reversal symmetry (TRS) is maintained, the pertinent topological phase transition, marked by re-entrant 2 e2/h quantized conductance contributed by helical edge states, is driven by disorder. Here we show that when TRS is broken, the physics of the TAI becomes even richer. The pattern of longitudinal conductance and nonequilibrium local current distribution displays novel TAI phases characterized by nonzero Chern numbers, indicating the occurrence of multiple chiral edge modes. Tuning either disorder or Fermi energy (in both topologically trivial and nontrivial phases), drives transitions between these distinct TAI phases, characterized by jumps of the quantized conductance from 0 to e2/h and from e2/h to 2 e2/h . An effective medium theory based on the Born approximation yields an accurate description of different TAI phases in parameter space.

  8. Universal Knight shift anomaly in the periodic Anderson model

    SciTech Connect

    Jiang, M.; Curro, N. J.; Scalettar, R. T.

    2014-12-12

    Here, we report a Determinant Quantum Monte Carlo investigation which quantifies the behavior of the susceptibility and the entropy in the framework of the periodic Anderson model (PAM), focussing on the evolution with different degree of conduction electron (c) -local moment (f) hybridization. These results capture the behavior observed in several experiments, including the universal behavior of the NMR Knight shift anomaly below the crossover temperature, T*. We find that T* is a measure of the onset of c-f correlations and grows with increasing hybridization. Our results suggest that the NMR Knight shift and spin-lattice relaxation rate measurements in non-Fermi liquid materials are strongly influenced by temperature-dependent hybridization processes. Furthermore, our results provide a microscopic basis for the phenomenological two-fluid model of Kondo lattice behavior, and its evolution with pressure and temperature.

  9. Universal Knight shift anomaly in the periodic Anderson model

    DOE PAGES

    Jiang, M.; Curro, N. J.; Scalettar, R. T.

    2014-12-12

    Here, we report a Determinant Quantum Monte Carlo investigation which quantifies the behavior of the susceptibility and the entropy in the framework of the periodic Anderson model (PAM), focussing on the evolution with different degree of conduction electron (c) -local moment (f) hybridization. These results capture the behavior observed in several experiments, including the universal behavior of the NMR Knight shift anomaly below the crossover temperature, T*. We find that T* is a measure of the onset of c-f correlations and grows with increasing hybridization. Our results suggest that the NMR Knight shift and spin-lattice relaxation rate measurements in non-Fermimore » liquid materials are strongly influenced by temperature-dependent hybridization processes. Furthermore, our results provide a microscopic basis for the phenomenological two-fluid model of Kondo lattice behavior, and its evolution with pressure and temperature.« less

  10. Universal Knight shift anomaly in the periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Jiang, M.; Curro, N. J.; Scalettar, R. T.

    2014-12-01

    We report a determinant Quantum Monte Carlo investigation which quantifies the behavior of the susceptibility and the entropy in the framework of the periodic Anderson model, focusing on the evolution with different degree of conduction electron (c )-local moment (f ) hybridization. These results capture the behavior observed in several experiments, including the universal behavior of the NMR Knight shift anomaly below the crossover temperature T*. We find that T* is a measure of the onset of c - f correlations and grows with increasing hybridization. These results suggest that the NMR Knight shift and spin-lattice relaxation rate measurements in non-Fermi-liquid materials are strongly influenced by the temperature dependence of the c - f kinetic energy. Our results provide a microscopic basis for the phenomenological two-fluid model of Kondo lattice behavior, and its evolution with pressure and temperature.

  11. Nonequilibrium Anderson model made simple with density functional theory

    NASA Astrophysics Data System (ADS)

    Kurth, S.; Stefanucci, G.

    2016-12-01

    The single-impurity Anderson model is studied within the i-DFT framework, a recently proposed extension of density functional theory (DFT) for the description of electron transport in the steady state. i-DFT is designed to give both the steady current and density at the impurity, and it requires the knowledge of the exchange-correlation (xc) bias and on-site potential (gate). In this work we construct an approximation for both quantities which is accurate in a wide range of temperatures, gates, and biases, thus providing a simple and unifying framework to calculate the differential conductance at negligible computational cost in different regimes. Our results mark a substantial advance for DFT and may inform the construction of functionals applicable to other correlated systems.

  12. X-slave boson approach to the periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Franco, R.; Figueira, M. S.; Foglio, M. E.

    2001-05-01

    The periodic anderson model (PAM) in the limit U=∞, can be studied by employing the Hubbard X operators to project out the unwanted states. In a previous work, we have studied the cumulant expansion of this Hamiltonian employing the hybridization as a perturbation, but probability conservation of the local states (completeness) is not usually satisfied when partial expansions like the "chain approximation (CHA)" are employed. To consider this problem, we use a technique similar to the one employed by Coleman to treat the same problem with slave-bosons in the mean-field approximation. Assuming a particular renormalization for hybridization, we obtain a description that avoids an unwanted phase transition that appears in the mean-field slave-boson method at intermediate temperatures.

  13. X-boson cumulant approach to the periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Franco, R.; Figueira, M. S.; Foglio, M. E.

    2002-07-01

    The periodic Anderson model can be studied in the limit U=∞ by employing the Hubbard X operators to project out the unwanted states. We had already studied this problem by employing the cumulant expansion with the hybridization as perturbation, but the probability conservation of the local states (completeness) is not usually satisfied when partial expansions like the ``chain approximation'' (CHA) are employed. To rectify this situation, we modify the CHA by employing a procedure that was used in the mean-field approximation of Coleman's slave-boson method. Our technique reproduces the features of that method in its region of validity, but avoids the unwanted phase transition that appears in the same method both when μ>>Ef at low T and for all values of the parameters at intermediate temperatures. Our method also has a dynamic character that is absent from the mean-field slave-boson method.

  14. Anderson localization of composite excitations in disordered optomechanical arrays

    NASA Astrophysics Data System (ADS)

    Figueiredo Roque, Thales; Peano, Vittorio; Yevtushenko, Oleg M.; Marquardt, Florian

    2017-01-01

    Optomechanical (OMA) arrays are a promising future platform for studies of transport, many-body dynamics, quantum control and topological effects in systems of coupled photon and phonon modes. We introduce disordered OMA arrays, focusing on features of Anderson localization of hybrid photon-phonon excitations. It turns out that these represent a unique disordered system, where basic parameters can be easily controlled by varying the frequency and the amplitude of an external laser field. We show that the two-species setting leads to a non-trivial frequency dependence of the localization length for intermediate laser intensities. This could serve as a convincing evidence of localization in a non-equilibrium dissipative situation.

  15. Permittivity disorder induced Anderson localization in magnetophotonic crystals

    NASA Astrophysics Data System (ADS)

    Abdi-Ghaleh, R.; Namdar, A.

    2016-11-01

    This theoretical study was carried out to investigate the permittivity disorder induced Anderson localization of light in one-dimensional magnetophotonic crystals. It was shown that the disorder create the resonant transmittance modes associated with enhanced Faraday rotations inside the photonic band gap. The average localization length of the right- and left-handed circular polarizations (RCP and LCP), the total transmittance together with the ensemble average of the RCP and LCP phases, and the Faraday rotation of the structure were also investigated. For this purpose, the off-diagonal elements of the permittivity tensor were varied for various wavelengths of incident light. The obtained results revealed the nonreciprocal property of circular eigen modes. This study can potentially open up a new aspect for utilizing the disorder magnetophotonic structures in nonreciprocal systems such as isolators and circulators.

  16. Multi-Scale Jacobi Method for Anderson Localization

    NASA Astrophysics Data System (ADS)

    Imbrie, John Z.

    2015-11-01

    A new KAM-style proof of Anderson localization is obtained. A sequence of local rotations is defined, such that off-diagonal matrix elements of the Hamiltonian are driven rapidly to zero. This leads to the first proof via multi-scale analysis of exponential decay of the eigenfunction correlator (this implies strong dynamical localization). The method has been used in recent work on many-body localization (Imbrie in On many-body localization for quantum spin chains, arXiv:1403.7837 , 2014).

  17. Renormalization flow of the hierarchical Anderson model at weak disorder

    NASA Astrophysics Data System (ADS)

    Metz, F. L.; Leuzzi, L.; Parisi, G.

    2014-02-01

    We study the flow of the renormalized model parameters obtained from a sequence of simple transformations of the 1D Anderson model with long-range hierarchical hopping. Combining numerical results with a perturbative approach for the flow equations, we identify three qualitatively different regimes at weak disorder. For a sufficiently fast decay of the hopping energy, the Cauchy distribution is the only stable fixed point of the flow equations, whereas for sufficiently slowly decaying hopping energy the renormalized parameters flow to a δ-peak fixed-point distribution. In an intermediate range of the hopping decay, both fixed-point distributions are stable and the stationary solution is determined by the initial configuration of the random parameters. We present results for the critical decay of the hopping energy separating the different regimes.

  18. Anderson Localization: Dynamical Cluster Approximation - Typical Medium Theory Perspective

    NASA Astrophysics Data System (ADS)

    Ekuma, Chinedu; Meng, Ziyang; Terletska, Hanna; Moreno, Juana; Jarrell, Mark; Dobrosavljevic, Vladimir

    2013-03-01

    Mean field theories like the coherent potential approximation (CPA) and its cluster extensions, including the dynamical cluster approximation (DCA), fail to describe the Anderson localization transition in disordered systems. This failure is intrinsic to these theories as the algebraically averaged quantities used in them always favor the metallic state, and hence cannot describe the localization transition. Here we extend the Typical Medium Theory (TMT), which replaces the average quantities with their corresponding typical (geometrically averaged) equivalents, to its cluster form such that non-local correlations can be incorporated systematically. We apply our method to study the localization phenomena in various dimensions. Such an approach opens a new avenue to study localization effect both in model and in real materials. This work was supported by the National Science Foundation (NSF) [Award No. LA-SiGMA EPS-1003897, DMR-1005751], Department of Energy, DOE-CMCSN

  19. Diagram theory for the twofold-degenerate Anderson impurity model

    NASA Astrophysics Data System (ADS)

    Moskalenko, V. A.; Dohotaru, L. A.; Digor, D. F.; Cebotari, I. D.

    2014-02-01

    We develop a diagram technique for investigating the twofold-degenerate Anderson impurity model in the normal state with the strong electronic correlations of d electrons of the impurity ion taken into account. We discuss the properties of the Slater-Kanamori model of d electrons. After finding the eigenfunctions and eigenvalues of all 16 local states, we determine the local one-particle propagator. We construct the perturbation theory around the atomic limit of the impurity ion and obtain a Dyson-type equation establishing the relation between the impurity electron propagator and the normal correlation function. As a result of summing infinite series of ladder diagrams, we obtain an approximation for the correlation function.

  20. Multi-level Algorithm for the Anderson Impurity Model

    NASA Astrophysics Data System (ADS)

    Chandrasekharan, S.; Yoo, J.; Baranger, H. U.

    2004-03-01

    We develop a new quantum Monte Carlo algorithm to solve the Anderson impurity model. Instead of integrating out the Fermions, we work in the Fermion occupation number basis and thus have direct access to the Fermionic physics. The sign problem that arises in this formulation can be solved by a multi-level technique developed by Luscher and Weisz in the context of lattice QCD [JHEP, 0109 (2001) 010]. We use the directed-loop algorithm to update the degrees of freedom. Further, this algorithm allows us to work directly in the Euclidean time continuum limit for arbitrary values of the interaction strength thus avoiding time discretization errors. We present results for the impurity susceptibility and the properties of the screening cloud obtained using the algorithm.

  1. The topological Anderson insulator phase in the Kane-Mele model

    NASA Astrophysics Data System (ADS)

    Orth, Christoph P.; Sekera, Tibor; Bruder, Christoph; Schmidt, Thomas L.

    2016-04-01

    It has been proposed that adding disorder to a topologically trivial mercury telluride/cadmium telluride (HgTe/CdTe) quantum well can induce a transition to a topologically nontrivial state. The resulting state was termed topological Anderson insulator and was found in computer simulations of the Bernevig-Hughes-Zhang model. Here, we show that the topological Anderson insulator is a more universal phenomenon and also appears in the Kane-Mele model of topological insulators on a honeycomb lattice. We numerically investigate the interplay of the relevant parameters, and establish the parameter range in which the topological Anderson insulator exists. A staggered sublattice potential turns out to be a necessary condition for the transition to the topological Anderson insulator. For weak enough disorder, a calculation based on the lowest-order Born approximation reproduces quantitatively the numerical data. Our results thus considerably increase the number of candidate materials for the topological Anderson insulator phase.

  2. The topological Anderson insulator phase in the Kane-Mele model.

    PubMed

    Orth, Christoph P; Sekera, Tibor; Bruder, Christoph; Schmidt, Thomas L

    2016-04-05

    It has been proposed that adding disorder to a topologically trivial mercury telluride/cadmium telluride (HgTe/CdTe) quantum well can induce a transition to a topologically nontrivial state. The resulting state was termed topological Anderson insulator and was found in computer simulations of the Bernevig-Hughes-Zhang model. Here, we show that the topological Anderson insulator is a more universal phenomenon and also appears in the Kane-Mele model of topological insulators on a honeycomb lattice. We numerically investigate the interplay of the relevant parameters, and establish the parameter range in which the topological Anderson insulator exists. A staggered sublattice potential turns out to be a necessary condition for the transition to the topological Anderson insulator. For weak enough disorder, a calculation based on the lowest-order Born approximation reproduces quantitatively the numerical data. Our results thus considerably increase the number of candidate materials for the topological Anderson insulator phase.

  3. The topological Anderson insulator phase in the Kane-Mele model

    PubMed Central

    Orth, Christoph P.; Sekera, Tibor; Bruder, Christoph; Schmidt, Thomas L.

    2016-01-01

    It has been proposed that adding disorder to a topologically trivial mercury telluride/cadmium telluride (HgTe/CdTe) quantum well can induce a transition to a topologically nontrivial state. The resulting state was termed topological Anderson insulator and was found in computer simulations of the Bernevig-Hughes-Zhang model. Here, we show that the topological Anderson insulator is a more universal phenomenon and also appears in the Kane-Mele model of topological insulators on a honeycomb lattice. We numerically investigate the interplay of the relevant parameters, and establish the parameter range in which the topological Anderson insulator exists. A staggered sublattice potential turns out to be a necessary condition for the transition to the topological Anderson insulator. For weak enough disorder, a calculation based on the lowest-order Born approximation reproduces quantitatively the numerical data. Our results thus considerably increase the number of candidate materials for the topological Anderson insulator phase. PMID:27045779

  4. Integrals of motion for one-dimensional Anderson localized systems

    DOE PAGES

    Modak, Ranjan; Mukerjee, Subroto; Yuzbashyan, Emil A.; ...

    2016-03-02

    Anderson localization is known to be inevitable in one-dimension for generic disordered models. Since localization leads to Poissonian energy level statistics, we ask if localized systems possess ‘additional’ integrals of motion as well, so as to enhance the analogy with quantum integrable systems. Weanswer this in the affirmative in the present work. We construct a set of nontrivial integrals of motion for Anderson localized models, in terms of the original creation and annihilation operators. These are found as a power series in the hopping parameter. The recently found Type-1 Hamiltonians, which are known to be quantum integrable in a precisemore » sense, motivate our construction.Wenote that these models can be viewed as disordered electron models with infinite-range hopping, where a similar series truncates at the linear order.Weshow that despite the infinite range hopping, all states but one are localized.Wealso study the conservation laws for the disorder free Aubry–Andre model, where the states are either localized or extended, depending on the strength of a coupling constant.Weformulate a specific procedure for averaging over disorder, in order to examine the convergence of the power series. Using this procedure in the Aubry–Andre model, we show that integrals of motion given by our construction are well-defined in localized phase, but not so in the extended phase. Lastly, we also obtain the integrals of motion for a model with interactions to lowest order in the interaction.« less

  5. [Immunohistochemical assay of cellular cycle markers: an alternative to chip-diagnosis of breast cancer].

    PubMed

    Petrov, S V; Orlova, R V; Raskin, G A; Khacanov, R Sh

    2007-01-01

    A new method of evaluation of immunohistochemical markers of cellular cycle (K-67, topoisomerase-II-alpha, P21/wafl), adhesion molecules (E-cadherin, CD33v6), oncoprotein HER-2, and estrogen and progesterone receptors of tumor is presented. High-precision count of tumor cells, which express each marker, was carried out using serial paraffin sections and Leica CTR5000 morphometric station and Leica Quin Plus program, to identify tumor sensitivity to anthracyclines and taxanes. Proliferative potential, tumor sensitivity to key chemical drugs and prognosis were evaluated on the basis of the evidence obtained and, in particular, the role of the proteins under study played in cellular cycle.

  6. Random Walks in Anderson's Garden: A Journey from Cuprates to Cooper Pair Insulators and Beyond

    NASA Astrophysics Data System (ADS)

    Baskaran, G.

    Anderson's Garden is a drawing presented to Philip W. Anderson on the eve of his 60th birthday celebration, in 1983, by a colleague (author unknown). This cartoon (Fig. 1) succinctly depicts some of Anderson's pre-1983 works. As an avid reader of Anderson's papers, a random walk in Anderson's garden had become a part of my routine since graduate school days. This was of immense help and prepared me for a wonderful collaboration with Anderson on the theory of high-Tc cuprates and quantum spin liquids at Princeton. Here I narrate this story, ending with a brief summary of my ongoing theoretical efforts to extend Anderson's RVB theory for superconductivity to encompass the recently observed high-temperature (Tc ~ 203K) superconductivity in solid H2S at pressure ~200GPa. In H2S molecule, four valence electrons form two saturated covalent bonds, H-S-H. These bond singlets are confined Cooper pairs close to chemical potential. Solid H2S is a Cooper pair insulator. Pressure changes the structure and not the number of valence electrons. Bond singlet pairing tendency continues and new S-S and H-H bonds are formed. S-S bonds are mostly saturated. However, hydrogen sublattice has unsaturated H-H bonds. It prepares ground for a RVB superconducting state.

  7. Correlation Effects in One-Dimensional Quasiperiodic Anderson-Lattice Model

    NASA Astrophysics Data System (ADS)

    Matsuda, Fuyuki; Tezuka, Masaki; Kawakami, Norio

    We consider the one-dimensional (1D) quasiperiodic Anderson-lattice model, which has quasiperiodically ordered impurities. The sites with an f-orbital are ordered as a "Fibonacci word", one way to form 1D quasiperiodic orderings. To treat the correlation effect precisely, we use the density matrix renormalization group (DMRG) method. We show that the spin correlation function in the quasiperiodic system gives a characteristic pattern. Also, by analyzing the f-electron number and its fluctuation, we find that a valence transition, which usually occurs in the periodic Anderson model when the on-site interorbital interaction is large, is not sharp in the quasiperiodic system. Finally, we discuss the properties of the quasiperiodic Anderson-lattice model, comparing them against the Anderson-lattice model with randomly located f-orbitals. We find that the quasiperiodic Anderson-lattice model has a similar property to the periodic Anderson model for spin correlation, but also has a similar property to the Anderson-lattice model with randomly located f-orbitals for the valence fluctuation.

  8. Luminescent Copper(I) Halide Butterfly Dimers Coordinated to [Au(CH3imCH2py)2]BF4 and [Au(CH3imCH2quin)2]BF4

    SciTech Connect

    Catalano, V.; Moore, A; Shearer, J; Kim, J

    2009-01-01

    The coordination chemistry of copper(I) halides to the homoleptic, N-heterocyclic carbene Au(I) complexes [Au(CH{sub 3}imCH{sub 2}quin){sub 2}]BF{sub 4} and [Au(CH{sub 3}imCH{sub 2}py){sub 2}]BF{sub 4} was explored. The reaction of CuX (X = Cl, Br, I) with either [Au(CH{sub 3}imCH{sub 2}quin){sub 2}]BF{sub 4} or [Au(CH{sub 3}imCH{sub 2}py){sub 2}]BF{sub 4} produces trimetallic complexes containing Cu{sub 2}X{sub 2}-butterfly copper clusters coordinated to the two imine moieties. The triangular arrangement of the metals places the gold(I) center in close proximity ({approx}2.5-2.6 {angstrom}) to the centroid of the Cu-Cu vector. The Cu-Cu separations vary as a function of bridging halide with the shortest Cu-Cu separations of {approx}2.5 {angstrom} found in the iodo-complexes and the longest separations of 2.9 {angstrom} found in the bridging chloride complexes. In all six complexes the Au-Cu separations range from {approx}2.8 to 3.0 {angstrom}. In the absence of halides, the dimetallic complex [AuCu(CH{sub 3}imCH{sub 2}py){sub 2}(NCCH{sub 3}){sub 2}](BF{sub 4}){sub 2}, containing a long Au-Cu distance of {approx}4.72 {angstrom} is formed. Additionally, as the byproduct of the reaction of CuBr with [Au(CH{sub 3}imCH{sub 2}quin){sub 2}]BF{sub 4} the deep-red, dimetallic compound, AuCuBr{sub 2}(CH{sub 3}imCH{sub 2}quin){sub 2}, was isolated in very low yield. All of these complexes were studied by NMR spectroscopy, mass spectrometry, and the copper containing species were additionally characterized by X-ray crystallography. In solution the copper centers dissociate from the gold complexes, but as shown by XANES and EXAFS spectroscopy, at low temperature the Cu-Cu linkage is broken, and the individual copper(I) halides reposition themselves to opposite sides of the gold complex while remaining coordinated to one imine moiety. In the solid state all of the complexes are photoluminescent, though the nature of the excited state was not determined.

  9. Two-photon Anderson localization in a disordered quadratic waveguide array

    NASA Astrophysics Data System (ADS)

    Bai, Y. F.; Xu, P.; Lu, L. L.; Zhong, M. L.; Zhu, S. N.

    2016-05-01

    We theoretically investigate two-photon Anderson localization in a χ (2) waveguide array with off-diagonal disorder. The nonlinear parametric down-conversion process would enhance both the single-photon and the two-photon Anderson localization. In the strong disorder regime, the two-photon position correlation exhibits a bunching distribution around the pumped waveguides, which is independent of pumping conditions and geometrical structures of waveguide arrays. Quadratic nonlinearity can be supplied as a new ingredient for Anderson localization. Also, our results pave the way for engineering quantum states through nonlinear quantum walks.

  10. Some comments on Anderson and Pospahala's correction of bias in line transect sampling

    USGS Publications Warehouse

    Anderson, D.R.; Burnham, K.P.; Chain, B.R.

    1980-01-01

    ANDERSON and POSPAHALA (1970) investigated the estimation of wildlife population size using the belt or line transect sampling method and devised a correction for bias, thus leading to an estimator with interesting characteristics. This work was given a uniform mathematical framework in BURNHAM and ANDERSON (1976). In this paper we show that the ANDERSON-POSPAHALA estimator is optimal in the sense of being the (unique) best linear unbiased estimator within the class of estimators which are linear combinations of cell frequencies, provided certain assumptions are met.

  11. Quantum criticality at the Anderson transition: A typical medium theory perspective

    NASA Astrophysics Data System (ADS)

    Mahmoudian, Samiyeh; Tang, Shao; Dobrosavljević, Vladimir

    2015-10-01

    We present a complete analytical and numerical solution of the typical medium theory (TMT) for the Anderson metal-insulator transition. This approach self-consistently calculates the typical amplitude of the electronic wave functions, thus representing the conceptually simplest order-parameter theory for the Anderson transition. We identify all possible universality classes for the critical behavior, which can be found within such a mean-field approach. This provides insights into how interaction-induced renormalizations of the disorder potential may produce qualitative modifications of the critical behavior. We also formulate a simplified description of the leading critical behavior, thus obtaining an effective Landau theory for Anderson localization.

  12. Typical medium dynamical cluster approximation for the study of Anderson localization in three dimensions

    NASA Astrophysics Data System (ADS)

    Ekuma, C. E.; Terletska, H.; Tam, K.-M.; Meng, Z.-Y.; Moreno, J.; Jarrell, M.

    2014-02-01

    We develop a systematic typical medium dynamical cluster approximation that provides a proper description of the Anderson localization transition in three dimensions (3D). Our method successfully captures the localization phenomenon both in the low and large disorder regimes, and allows us to study the localization in different momenta cells, which renders the discovery that the Anderson localization transition occurs in a cell-selective fashion. As a function of cluster size, our method systematically recovers the reentrance behavior of the mobility edge and obtains the correct critical disorder strength for Anderson localization in 3D.

  13. View of Anderson during a session of EVA on Expedition 15

    NASA Image and Video Library

    2007-07-23

    ISS015-E-19120 (23 July 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, waves to the camera while participating in a session of extravehicular activity (EVA) as construction continues on the International Space Station. During the 7-hour 41-minute spacewalk, Anderson and cosmonaut Fyodor N. Yurchikhin (out of frame), commander representing Russia's Federal Space Agency, installed a television camera stanchion, reconfigured a power supply for an antenna assembly, and performed several get-ahead tasks. Also, while riding on the end of the Canadarm2, Anderson jettisoned the Early Ammonia Servicer (EAS) by shoving it opposite of the station's direction of travel.

  14. View of Anderson during a session of EVA on Expedition 15

    NASA Image and Video Library

    2007-07-23

    ISS015-E-19114 (23 July 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, waves to the camera while participating in a session of extravehicular activity (EVA) as construction continues on the International Space Station. During the 7-hour 41-minute spacewalk, Anderson and cosmonaut Fyodor N. Yurchikhin (out of frame), commander representing Russia's Federal Space Agency, installed a television camera stanchion, reconfigured a power supply for an antenna assembly, and performed several get-ahead tasks. Also, while riding on the end of the Canadarm2, Anderson jettisoned the Early Ammonia Servicer (EAS) by shoving it opposite of the station's direction of travel.

  15. View of Anderson posing for a photo during an Expedition 15 EVA

    NASA Image and Video Library

    2007-07-23

    ISS015-E-18958 (23 July 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, waves to the camera while participating in a session of extravehicular activity (EVA) as construction continues on the International Space Station. During the 7-hour 41-minute spacewalk, Anderson and cosmonaut Fyodor N. Yurchikhin (out of frame), commander representing Russia's Federal Space Agency, installed a television camera stanchion, reconfigured a power supply for an antenna assembly, and performed several get-ahead tasks. Also, while riding on the end of the Canadarm2, Anderson jettisoned the Early Ammonia Servicer (EAS) by shoving it opposite of the station's direction of travel. The station's robotic arm end effector is at left.

  16. View of Anderson entering the Node 1 CBM after a session of EVA on Expedition 15

    NASA Image and Video Library

    2007-07-23

    ISS015-E-19179 (23 July 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, enters the Quest Airlock on the International Space Station at the conclusion of today's session of extravehicular activity (EVA). During the 7-hour 41-minute spacewalk, Anderson and cosmonaut Fyodor N. Yurchikhin (out of frame), commander representing Russia's Federal Space Agency, installed a television camera stanchion, reconfigured a power supply for an antenna assembly, and performed several get-ahead tasks. Also, while riding on the end of the Canadarm2, Anderson jettisoned the Early Ammonia Servicer (EAS) by shoving it opposite of the station's direction of travel.

  17. View of Anderson entering the Node 1 CBM after a session of EVA on Expedition 15

    NASA Image and Video Library

    2007-07-23

    ISS015-E-19165 (23 July 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, enters the Quest Airlock on the International Space Station at the conclusion of today's session of extravehicular activity (EVA). During the 7-hour 41-minute spacewalk, Anderson and cosmonaut Fyodor N. Yurchikhin (out of frame), commander representing Russia's Federal Space Agency, installed a television camera stanchion, reconfigured a power supply for an antenna assembly, and performed several get-ahead tasks. Also, while riding on the end of the Canadarm2, Anderson jettisoned the Early Ammonia Servicer (EAS) by shoving it opposite of the station's direction of travel.

  18. Anderson localisation on the Falicov-Kimball model with Coulomb disorder

    NASA Astrophysics Data System (ADS)

    Carvalho, Rubens D. B.; Almeida, Guilherme M. A.; Souza, Andre M. C.

    2014-07-01

    The role of Coulomb disorder is analysed in the Anderson-Falicov-Kimball model. Phase diagrams are obtained by means of dynamical mean-field theory applied to the Bethe lattice, in which metal-insulator transitions driven by Anderson and Coulomb disorder can be identified. Metallic, Mott insulator, and Anderson insulator phases, as well as the crossover between them are studied in this framework. We show that Coulomb disorder has a relevant role in the phase-transition behaviour as the system is led towards the insulator regime.

  19. Magnetic susceptibility for a two-channel Anderson model

    NASA Astrophysics Data System (ADS)

    Líbero, Valter L.; Ferreira, João V. B.; Oliveira, Luiz N.; Cox, Daniel L.

    2001-03-01

    Non-Fermi-liquid magnetic properties are studied using a generalized two-channel Anderson model suitable for compounds like U_xTh_1-xRu_2Si2 or La_1-xCe_xCu_2.2Si2 in the low concentration regime, for which single-site characteristics of the f-electrons are experimentally evident^1. The model encompasses a spin doublet and two (degenerate) channel doublets as impurity levels, opening two channels in the conduction band, with hybridization strength V1 and V_2. The interleaving Numerical Renormalization Group procedure^2,3 determines the temperature-dependent susceptibility \\chi. For the isotropic case V_1=V2 non-Fermi liquid behavior, \\chi ≈ -ln T, is obtained. This non-trivial fixed-point, however, is unstable against channel anisotropy: for V1 ne V2 normal-Fermi liquid behavior is recovered. 1- Tae-Suk Kim and D. L. Cox, Phys. Rev. Lett. 75, 1622 (1995). 2- S. C. Costa, C. A. Paula, V. L. Líbero and L. N. Oliveira, Phys. Rev. B 55, 30 (1997). 3- J. V. B. Ferreira and V. L. Líbero, Phys. Rev. B 61, 10615 (2000).

  20. The Knight shift anomaly in the disordered periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Dos Santos, Raimundo; Costa, Natanael; Paiva, Thereza; Curro, Nicholas; Scalettar, Richard

    In some materials, the coherence temperature T* signals the regime in which one has a heavy-electron fluid and `dissolved' local moments. An experimental signature of T* is provided by the Knight shift anomaly in NMR measurements. Further, the contribution of the heavy-electron fluid to the Knigh shift, KHF, displays universal character over a wide range of temperatures. An important probe of the physical mechanisms at play is the random substitution of say, La for Ce in CeRhIn5: this amounts to removing local moments at random sites, and one may wonder whether these universal features are sensitive to the presence of disorder. The Periodic Anderson Model (PAM) captures many aspects of heavy-fermion materials, so here we consider the two-dimensional PAM with a fraction x of the f-sites removed at random. Through Determinant Quantum Monte Carlo simulations we find that universality of KHF persists even in the presence of disorder, which, in turn, allows us to establish that T* decreases monotonically with x, in agreement with available experimental data. Our simulations also shed light into the low temperature behavior of the disordered PAM at low temperatures: the spin liquid phase of the local moments is suppressed upon dilution.

  1. The completeness problem in the impurity Anderson model

    NASA Astrophysics Data System (ADS)

    Lobo, T.; Figueira, M. S.; Franco, R.; Silva-Valencia, J.; Foglio, M. E.

    2007-09-01

    With the recent development of the nanoscopic technology, the impurity Anderson model (AIM) was experimentally realized in quantum dot devices, and there is renewed interest in the study of the Kondo physics of the AIM. Several Green's functions approximations by the equation of motion method (EOM), that incorporates the Kondo effect through a digamma function, have been presented in the literature as an adequate tool to describe, at least qualitatively, the Kondo effect. However, these approximations present several drawbacks: they are no longer valid as the temperature decreases below the Kondo temperature, because the logarithmic divergence of the digamma function makes the spectral density at the chemical potential to vanish, and the Friedel sum rule and the completeness in the occupation numbers are not fulfilled. In this work we present a critical discussion comparing the results of digamma approximations GF with the atomic approach, recently developed by some of us, that satisfy the completeness and the Friedel sum rule. We present results for the density of states, the Friedel sum rule and the completeness.

  2. Pressure dependence of the magnetic order on the Anderson lattice

    NASA Astrophysics Data System (ADS)

    Bernhard, B. H.; Aguiar, C.; Coqblin, B.

    2006-05-01

    The Anderson lattice model is employed in the description of several rare-earth compounds exhibiting charge fluctuations. Here we address the model by means of Green's function technique introduced in [B.H. Bernhard, C. Lacroix, Phys. Rev. B 60 (1999) 12149]. The description of the magnetic phase is obtained from the analysis of the self-consistent magnetization curves. Calculations are performed specifically on a cubic lattice. The competition between the antiferromagnetic (AF) order and the Kondo effect is tuned by the control parameter V/Ef which simulates the effect of pressure. The T- p diagram of the model is obtained for different values of the ratio V/t. By accompanying the evolution of the quantum critical point (QCP), we are able to draw the phase diagram at T=0. The model admits the coexistence of AF order and Kondo behavior, with a clear reduction of the local Kondo correlation function as one penetrates in the AF region. We also investigate the variation of the staggered magnetization and the Néel temperature in the neighborhood of the QCP.

  3. Anomalous Anderson localization behaviors in disordered pseudospin systems.

    PubMed

    Fang, A; Zhang, Z Q; Louie, Steven G; Chan, C T

    2017-04-04

    We discovered unique Anderson localization behaviors of pseudospin systems in a 1D disordered potential. For a pseudospin-1 system, due to the absence of backscattering under normal incidence and the presence of a conical band structure, the wave localization behaviors are entirely different from those of conventional disordered systems. We show that there exists a critical strength of random potential ([Formula: see text]), which is equal to the incident energy ([Formula: see text]), below which the localization length [Formula: see text] decreases with the random strength [Formula: see text] for a fixed incident angle [Formula: see text] But the localization length drops abruptly to a minimum at [Formula: see text] and rises immediately afterward. The incident angle dependence of the localization length has different asymptotic behaviors in the two regions of random strength, with [Formula: see text] when [Formula: see text] and [Formula: see text] when [Formula: see text] The existence of a sharp transition at [Formula: see text] is due to the emergence of evanescent waves in the systems when [Formula: see text] Such localization behavior is unique to pseudospin-1 systems. For pseudospin-1/2 systems, there is also a minimum localization length as randomness increases, but the transition from decreasing to increasing localization length at the minimum is smooth rather than abrupt. In both decreasing and increasing regions, the [Formula: see text] dependence of the localization length has the same asymptotic behavior [Formula: see text].

  4. Anomalously suppressed localization in the two-channel Anderson model.

    PubMed

    Nguyen, Ba Phi; Kim, Kihong

    2012-04-04

    We study numerically the localization properties of a two-channel quasi-one-dimensional Anderson model with uncorrelated diagonal disorder within the nearest-neighbor tight-binding approximation. We calculate and analyze the disorder-averaged transmittance and the Lyapunov exponent. We find that the localization of the entire system is enhanced by increasing the interchain hopping strength t̃. From the numerical investigation of the energy dependence of the Lyapunov exponent for many different interchain hopping strengths, we find that apart from the band center anomaly, which usually occurs in strictly one-dimensional disordered systems, additional anomalies appear at special spectral points. They are found to be associated with the interchain hopping strength and occur at E = ± t̃/2 and ± t̃. We find that the anomalies at E = ± t̃ are associated with the π-coupling occurring within one energy band and those at E = ± t̃/2 are associated with the π-coupling occurring between two different energy bands. Despite having a similar origin, these two anomalies have distinct characteristics in their dependence on the strength of disorder. We also show that for a suitable range of parameter values, effectively delocalized states are observed in finite-size systems.

  5. Spin susceptibility of Anderson impurities in arbitrary conduction bands

    NASA Astrophysics Data System (ADS)

    Fang, Tie-Feng; Tong, Ning-Hua; Cao, Zhan; Sun, Qing-Feng; Luo, Hong-Gang

    2015-10-01

    Spin susceptibility of Anderson impurities is a key quantity in understanding the physics of Kondo screening. Traditional numerical renormalization group (NRG) calculation of the impurity contribution χimp to susceptibility, defined originally by Wilson in a flat wide band, has been generalized before to structured conduction bands. The results brought about non-Fermi-liquid and diamagnetic Kondo behaviors in χimp, even when the bands are not gapped at the Fermi energy. Here, we use the full density-matrix (FDM) NRG to present high-quality data for the local susceptibility χloc and to compare them with χimp obtained by the traditional NRG. Our results indicate that those exotic behaviors observed in χimp are unphysical. Instead, the low-energy excitations of the impurity in arbitrary bands only without gap at the Fermi energy are still a Fermi liquid and paramagnetic. We also demonstrate that unlike the traditional NRG yielding χloc less accurate than χimp, the FDM method allows a high-precision dynamical calculation of χloc at much reduced computational cost, with an accuracy at least one order higher than χimp. Moreover, artifacts in the FDM algorithm to χimp and origins of the spurious non-Fermi-liquid and diamagnetic features are clarified. Our work provides an efficient high-precision algorithm to calculate the spin susceptibility of impurity for arbitrary structured bands, while negating the applicability of Wilson's definition to such cases.

  6. Scaling theory of Anderson localization: A renormalization-group approach

    NASA Astrophysics Data System (ADS)

    Sarker, Sanjoy; Domany, Eytan

    1981-06-01

    A position-space renormalization-group method, suitable for studying the localization properties of electrons in a disordered system, was developed. Two different approximations to a well-defined exact procedure were used. The first method is a perturbative treatment to lowest order in the intercell couplings. This yields a localization edge in three dimensions, with a fixed point at the band center (E=0) at a critical disorder σc~=7.0. In the neighborhood of the fixed point the localization length L is predicted to diverge as L~(σ-σc+βE2)-ν. In two dimensions no fixed point is found, indicating localization even for small randomness, in agreement with Abrahams, Anderson, Licciardello, and Ramakrishnan. The second method is an application of the finite-lattice approximation, in which the intercell hopping between two (or more) cells is treated to infinite order in perturbation theory. To our knowledge, this method has not been previously used for quantum systems. Calculations based on this approximation were carried out in two dimensions only, yielding results that are in agreement with those of the lowest-order approximation.

  7. Anderson metal-insulator transitions with classical magnetic impurities

    SciTech Connect

    Jung, Daniel; Kettemann, Stefan

    2014-08-20

    We study the effects of classical magnetic impurities on the Anderson metal-insulator transition (AMIT) numerically. In particular we find that while a finite concentration of Ising impurities lowers the critical value of the site-diagonal disorder amplitude W{sub c}, in the presence of Heisenberg impurities, W{sub c} is first increased with increasing exchange coupling strength J due to time-reversal symmetry breaking. The resulting scaling with J is compared to analytical predictions by Wegner [1]. The results are obtained numerically, based on a finite-size scaling procedure for the typical density of states [2], which is the geometric average of the local density of states. The latter can efficiently be calculated using the kernel polynomial method [3]. Although still suffering from methodical shortcomings, our method proves to deliver results close to established results for the orthogonal symmetry class [4]. We extend previous approaches [5] by combining the KPM with a finite-size scaling analysis. We also discuss the relevance of our findings for systems like phosphor-doped silicon (Si:P), which are known to exhibit a quantum phase transition from metal to insulator driven by the interplay of both interaction and disorder, accompanied by the presence of a finite concentration of magnetic moments [6].

  8. Reply to Comment on Theory of impure superconductors: Anderson versus Abrikosov and Gor'kov' ''

    SciTech Connect

    Kim, Y.; Overhauser, A.W. )

    1994-05-01

    That the Abrikosov-Gor'kov theory of an impure superconductor seriously violates Anderson's theorem is reaffirmed. The contrary assertion, together with other statements in the Comment, are shown to be incorrect physically, mathematically, and historically.

  9. Hormonal profile and fertility in patients with Anderson-Fabry disease.

    PubMed

    Hauser, A C; Gessl, A; Harm, F; Wiesholzer, M; Kleinert, J; Wallner, M; Voigtländer, T; Bieglmayer, C; Sunder-Plassmann, G

    2005-09-01

    Anderson-Fabry disease is a glycosphingolipid storage disorder with an X-linked recessive inheritance. The alpha-galactosidase A deficiency leads to a progressive accumulation of globotriaosylceramide in the endothelium and tissue cells of various organs. The kidney, heart and brain are predominantly affected. Reports on endocrine function and fertility rates in patients with Anderson-Fabry disease are sparse. In the present study, we assessed ovarian, testicular and adrenal function in a cohort of patients with Anderson-Fabry disease. Plasma follicle-stimulating hormone, luteinizing hormone, prolactin, estradiol, testosterone, sex hormone-binding globulin, somatotropin, insulin-like growth factor-I and serum cortisol were measured in 13 patients (six female and seven male), currently observed in an outpatient clinic. The profile revealed an undisturbed hormonal function and a normal fertility rate in both male and female Anderson-Fabry patients when compared with the corresponding Austrian population.

  10. A Brief History of Thoracic Surgery at the University of Texas MD Anderson Cancer Center.

    PubMed

    Walsh, Garrett Lyndon; Mehran, Reza John

    2016-01-01

    This article describes the history of the creation of the Department of Thoracic Surgery at the University of Texas MD Anderson Cancer Center in Houston, Texas. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. View of Anderson working with the ISS Ham Radio in the SM during Expedition 15

    NASA Image and Video Library

    2007-09-26

    ISS015-E-29992 (26 Sept. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, smiles for a photo while using a communication system in the Zvezda Service Module of the International Space Station.

  12. View of Anderson posing for a photo in the SM during Expedition 15

    NASA Image and Video Library

    2007-07-21

    ISS015-E-19264 (24 July 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, wearing communication headgear, smiles for the camera as he floats in the Zvezda Service Module of the International Space Station.

  13. View of Anderson posing for a photo in the SM during Expedition 15

    NASA Image and Video Library

    2007-07-21

    ISS015-E-18872 (21 July 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, poses for a photo with food packets floating freely in the Zvezda Service Module of the International Space Station.

  14. View of Expedition 15 FE Anderson posing for a photo in a Soyuz Spacecraft

    NASA Image and Video Library

    2007-09-27

    ISS015-E-31308 (27 Sept. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, uses a camera in the Soyuz TMA-10 spacecraft docked to the Zarya module nadir port of the International Space Station.

  15. Anderson gathers air samples in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-10-03

    ISS015-E-31717 (3 Oct. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, poses with a microbial air sampler (MAS) and petri dish in the Destiny laboratory of the International Space Station.

  16. View of Anderson working on the EMCS in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-07-05

    ISS015-E-17670 (5 July 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, works with a European Modular Cultivation System (EMCS) in the Destiny laboratory of the International Space Station.

  17. View of Anderson posing for a photo in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-09-03

    ISS015-E-27279 (3 Sept. 2007) --- NASA astronaut Clay Anderson, Expedition 15 flight engineer, poses for a photo near the Earth observation window in the Destiny laboratory of the International Space Station.

  18. View of Anderson posing for photo in the A/L during Expedition 15

    NASA Image and Video Library

    2007-07-19

    ISS015-E-19537 (19 July 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, poses for a photo with two extravehicular mobility units (EMU) in the Quest Airlock of the International Space Station

  19. Anderson gathers air samples in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-10-03

    ISS015-E-31714 (3 Oct. 2007) --- NASA astronaut Clay Anderson, Expedition 15 flight engineer, poses with a microbial air sampler (MAS) and petri dish in the Destiny laboratory of the International Space Station.

  20. Anderson and Kotov posing for a photo in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-10-01

    ISS015-E-32309 (October 2007) --- NASA astronaut Clay Anderson (left) and Russian Federal Space Agency cosmonaut Oleg V. Kotov, both Expedition 15 flight engineers, pose for a photo in the Destiny laboratory of the International Space Station.

  1. Anderson floats in the aft FD on Space Shuttle Endeavor during Joint Operations

    NASA Image and Video Library

    2007-08-12

    ISS015-E-22180 (12 Aug. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, pauses for a photo while using a camera near the aft flight deck of Space Shuttle Endeavour while docked with the International Space Station.

  2. Anderson in the US Lab during Expedition 16 / STS-120 joint operations

    NASA Image and Video Library

    2007-11-04

    ISS016-E-009301 (4 Nov. 2007) --- Astronaut Clay Anderson, STS-120 mission specialist, uses a computer in the Destiny laboratory of the International Space Station while Space Shuttle Discovery is docked with the station.

  3. Adaptive Thouless-Anderson-Palmer approach to inverse Ising problems with quenched random fields

    NASA Astrophysics Data System (ADS)

    Huang, Haiping; Kabashima, Yoshiyuki

    2013-06-01

    The adaptive Thouless-Anderson-Palmer equation is derived for inverse Ising problems in the presence of quenched random fields. We test the proposed scheme on Sherrington-Kirkpatrick, Hopfield, and random orthogonal models and find that the adaptive Thouless-Anderson-Palmer approach allows accurate inference of quenched random fields whose distribution can be either Gaussian or bimodal. In particular, another competitive method for inferring external fields, namely, the naive mean field method with diagonal weights, is compared and discussed.

  4. Anderson localisation and optical-event horizons in rogue-soliton generation

    NASA Astrophysics Data System (ADS)

    Saleh, Mohammed F.; Conti, Claudio; Biancalana, Fabio

    2017-03-01

    We unveil the relation between the linear Anderson localisation process and nonlinear modulation instability. Anderson localised modes are formed in certain temporal intervals due to the random background noise. Such localised modes seed the formation of solitary waves that will appear during the modulation instability process at those preferred intervals. Afterwards, optical-event horizon effects between dispersive waves and solitons produce an artificial collective acceleration that favours the collision of solitons, which could eventually lead to a rogue-soliton generation.

  5. Parabolic Anderson Model in a Dynamic Random Environment: Random Conductances

    NASA Astrophysics Data System (ADS)

    Erhard, D.; den Hollander, F.; Maillard, G.

    2016-06-01

    The parabolic Anderson model is defined as the partial differential equation ∂ u( x, t)/ ∂ t = κ Δ u( x, t) + ξ( x, t) u( x, t), x ∈ ℤ d , t ≥ 0, where κ ∈ [0, ∞) is the diffusion constant, Δ is the discrete Laplacian, and ξ is a dynamic random environment that drives the equation. The initial condition u( x, 0) = u 0( x), x ∈ ℤ d , is typically taken to be non-negative and bounded. The solution of the parabolic Anderson equation describes the evolution of a field of particles performing independent simple random walks with binary branching: particles jump at rate 2 d κ, split into two at rate ξ ∨ 0, and die at rate (- ξ) ∨ 0. In earlier work we looked at the Lyapunov exponents λ p(κ ) = limlimits _{tto ∞} 1/t log {E} ([u(0,t)]p)^{1/p}, quad p in {N} , qquad λ 0(κ ) = limlimits _{tto ∞} 1/2 log u(0,t). For the former we derived quantitative results on the κ-dependence for four choices of ξ : space-time white noise, independent simple random walks, the exclusion process and the voter model. For the latter we obtained qualitative results under certain space-time mixing conditions on ξ. In the present paper we investigate what happens when κΔ is replaced by Δ𝓚, where 𝓚 = {𝓚( x, y) : x, y ∈ ℤ d , x ˜ y} is a collection of random conductances between neighbouring sites replacing the constant conductances κ in the homogeneous model. We show that the associated annealed Lyapunov exponents λ p (𝓚), p ∈ ℕ, are given by the formula λ p({K} ) = {sup} {λ p(κ ) : κ in {Supp} ({K} )}, where, for a fixed realisation of 𝓚, Supp(𝓚) is the set of values taken by the 𝓚-field. We also show that for the associated quenched Lyapunov exponent λ 0(𝓚) this formula only provides a lower bound, and we conjecture that an upper bound holds when Supp(𝓚) is replaced by its convex hull. Our proof is valid for three classes of reversible ξ, and for all 𝓚

  6. Clinical prodromes of neurodegeneration in Anderson-Fabry disease

    PubMed Central

    Hughes, Derralynn; Milligan, Alan; Richfield, Linda; Reichmann, Heinz; Mehta, Atul; Schapira, Anthony H.V.

    2015-01-01

    Objective: To estimate the prevalence of prodromal clinical features of neurodegeneration in patients with Anderson-Fabry disease (AFD) in comparison to age-matched controls. Methods: This is a single-center, prospective, cross-sectional study in 167 participants (60 heterozygous females and 50 hemizygous males with genetically confirmed AFD, 57 age-matched controls) using a clinical screening program consisting of structured interview, quantitative tests of motor function, and assessments of cognition, depression, olfaction, orthostatic intolerance, pain, REM sleep behavior disorder, and daytime sleepiness. Results: In comparison to age-matched controls (mean age 48.3 years), patients with AFD (mean age 49.0 years) showed slower gait and transfer speed, poorer fine manual dexterity, and lower hand speed, which was independent of focal symptoms due to cerebrovascular disease. Patients with AFD were more severely affected by depression, pain, and daytime sleepiness and had a lower quality of life. These motor and nonmotor manifestations significantly correlated with clinical disease severity. However, patients with AFD did not reveal extrapyramidal motor features or signs of significant cognitive impairment, hyposmia, orthostatic intolerance, or REM sleep behavior disorder, which commonly precede later neurodegenerative disease. In our cohort, there were no differences in neurologic manifestations of AFD between heterozygous females and hemizygous males. Conclusions: Aside from cerebrovascular manifestations and small fiber neuropathy, AFD results in a distinct neurologic phenotype comprising poorer motor performance and specific nonmotor features. In contrast to functional loss of glucocerebrosidase in Gaucher disease, α-galactosidase deficiency in AFD is not associated with a typical cluster of clinical features prodromal for neurodegenerative diseases, such as Parkinson disease. PMID:25762709

  7. Attractive Hubbard model with disorder and the generalized Anderson theorem

    SciTech Connect

    Kuchinskii, E. Z. Kuleeva, N. A. Sadovskii, M. V.

    2015-06-15

    Using the generalized DMFT+Σ approach, we study the influence of disorder on single-particle properties of the normal phase and the superconducting transition temperature in the attractive Hubbard model. A wide range of attractive potentials U is studied, from the weak coupling region, where both the instability of the normal phase and superconductivity are well described by the BCS model, to the strong-coupling region, where the superconducting transition is due to Bose-Einstein condensation (BEC) of compact Cooper pairs, formed at temperatures much higher than the superconducting transition temperature. We study two typical models of the conduction band with semi-elliptic and flat densities of states, respectively appropriate for three-dimensional and two-dimensional systems. For the semi-elliptic density of states, the disorder influence on all single-particle properties (e.g., density of states) is universal for an arbitrary strength of electronic correlations and disorder and is due to only the general disorder widening of the conduction band. In the case of a flat density of states, universality is absent in the general case, but still the disorder influence is mainly due to band widening, and the universal behavior is restored for large enough disorder. Using the combination of DMFT+Σ and Nozieres-Schmitt-Rink approximations, we study the disorder influence on the superconducting transition temperature T{sub c} for a range of characteristic values of U and disorder, including the BCS-BEC crossover region and the limit of strong-coupling. Disorder can either suppress T{sub c} (in the weak-coupling region) or significantly increase T{sub c} (in the strong-coupling region). However, in all cases, the generalized Anderson theorem is valid and all changes of the superconducting critical temperature are essentially due to only the general disorder widening of the conduction band.

  8. Anderson localization to enhance light-matter interaction (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Garcia, Pedro David

    2016-04-01

    Deliberately introducing disorder in low-dimensional nanostructures like photonic crystal waveguides (PCWs) [1] or photonic crystals (PCs) [2] leads to Anderson localization where light is efficiently trapped by random multiple scattering with the lattice imperfections. These disorder-induced optical modes hace been demonstrated to be very promising for cavity-quantum electrodynamics (QED) experiments where the radiative emission rate of single quantum emitters can be controlled when tuned through resonance with one of these random cavities. Our statistical analysis of the emission dynamics from single quantum dots embeded in disordered PCWs [3] provides detailed insigth about the statistical properties of QED in these complex nanostructures. In addition, using internal light sources reveals new physics in the form of nonuniversal intensity correlations between the different scattered paths within the structure which imprint the local QED properties deep inside the complex structure onto the far-field intensity pattern [2]. Finally, increasing the optical gain in PCWs allows on-chip random nanolasing where the cavity feedback is provided by the intrinsic disorder which enables highly efficient, stable, and broadband tunable lasers with very small mode volumes [4]. The figure of merit of these disorder-induced cavities is their localization length which determines to a large degree the coupling efficiency of a quantum emitter to a disorder-induced cavity as well as the efficiency of random lasing and reveals a strongly dispersive behavior and a non-trivial dependence on disorder in PCWs [5]. [1] L. Sapienza, H. Thyrrestrup, S. Stobbe, P.D. Garcia, S. Smolka, and P. Lodahl, Science 327, 1352 (2010). [2] P. D. García, S. Stobbe, I. Soellner and P. Lodahl, Physical Review Letters 109, 253902 (2012). [3] A. Javadi, S. Maibom, L. Sapienza, H. Thyrrestrup, P.D. Garcia, and P. Lodahl, Opt. Express 22, 30992 (2014). [4] J. Liu, P. D. Garcia, S. Ek, N. Gregersen, T. Suhr, M

  9. Anderson-Fabry disease: a case-finding study among male kidney transplant recipients in Austria.

    PubMed

    Kleinert, Julia; Kotanko, Peter; Spada, Marco; Pagliardini, Severo; Paschke, Eduard; Paul, Karl; Voigtländer, Till; Wallner, Manfred; Kramar, Reinhard; Stummvoll, Hans-Krister; Schwarz, Christoph; Horn, Sabine; Holzer, Herwig; Födinger, Manuela; Sunder-Plassmann, Gere

    2009-03-01

    The diagnosis of Anderson-Fabry disease is often delayed or even missed. As severe renal manifestations are a hallmark of alfa-galactosidase A (AGAL) deficiency, we tested the hypothesis that Anderson-Fabry disease is under-recognized among male kidney transplant recipients. This nation-wide study in Austria enrolled 1306 patients (ca 65% of all kidney transplanted males) from 30 kidney centers. AGAL activity was determined from filter paper dried blood spots by a fluorescence assay. A positive screening test was defined by an AGAL activity below 1.5 nmol/h/ml. In patients with a positive blood spot-screening test, AGAL activity was re-examined in peripheral blood leukocytes. Genetic testing for mutations in the GLA gene was performed by sequencing to confirm the diagnosis of Anderson-Fabry disease. Two previously not recognized cases with Anderson-Fabry disease were identified. Our study is the first showing that a diagnosis of Anderson-Fabry disease can be missed even in patients who undergo kidney transplantation. Case-finding strategies may be considered a useful tool for diagnosis of this rare disease that may be somewhat more prevalent among kidney transplant recipients compared with dialysis populations.

  10. Perfect transmission through Anderson localized systems mediated by a cluster of localized modes.

    PubMed

    Choi, Wonjun; Park, Q-Han; Choi, Wonshik

    2012-08-27

    In a strongly scattering medium where Anderson localization takes place, constructive interference of local non-propagating waves dominate over the incoherent addition of propagating waves. This results in the disappearance of propagating waves within the medium, which significantly attenuates energy transmission. In this numerical study performed in the optical regime, we systematically found resonance modes, called eigenchannels, of a 2-D Anderson localized system that allow for the near-perfect energy transmission. We observed that the internal field distribution of these eigenchannels exhibit dense clustering of localized modes. This strongly suggests that the clustered resonance modes facilitate long-range energy flow of local waves. Our study explicitly elucidates the interplay between wave localization and transmission enhancement in the Anderson localization regime.

  11. Melissa L. Anderson: APA/APAGS Award for Distinguished Graduate Student in Professional Psychology.

    PubMed

    2012-11-01

    Presents a short biography of the winner of the American Psychological Association/American Psychological Association of Graduate Students Award for Distinguished Graduate Student in Professional Psychology. The 2012 winner is Melissa L. Anderson for her ongoing commitment to understanding, treating, and preventing domestic violence in Deaf women and underserved populations in general. Anderson is passionate in her efforts to study the factors underlying violence toward women and in applying psychological science to intervene in and prevent such abuse. She is dedicated to improving the quality of life and well-being of underserved women and ensuring that services and programs become accessible to them. Anderson's Award citation is also presented. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  12. Transverse Anderson localization of light near Dirac points of photonic nanostructures

    PubMed Central

    Deng, Hanying; Chen, Xianfeng; Malomed, Boris A.; Panoiu, Nicolae C.; Ye, Fangwei

    2015-01-01

    We perform a comparative study of the Anderson localization of light beams in disordered layered photonic nanostructures that, in the limit of periodic layer distribution, possess either a Dirac point or a Bragg gap in the spectrum of the wavevectors. In particular, we demonstrate that the localization length of the Anderson modes increases when the width of the Bragg gap decreases, such that in the vanishingly small bandgap limit, namely when a Dirac point is formed, even extremely high levels of disorder are unable to localize the optical modes residing near the Dirac point. A comparative analysis of the key features of the propagation of Anderson modes formed in the Bragg gap or near the Dirac point is also presented. Our findings could provide valuable guidelines in assessing the influence of structural disorder on the functionality of a broad array of optical nanodevices. PMID:26498634

  13. Transverse Anderson localization of light near Dirac points of photonic nanostructures.

    PubMed

    Deng, Hanying; Chen, Xianfeng; Malomed, Boris A; Panoiu, Nicolae C; Ye, Fangwei

    2015-10-26

    We perform a comparative study of the Anderson localization of light beams in disordered layered photonic nanostructures that, in the limit of periodic layer distribution, possess either a Dirac point or a Bragg gap in the spectrum of the wavevectors. In particular, we demonstrate that the localization length of the Anderson modes increases when the width of the Bragg gap decreases, such that in the vanishingly small bandgap limit, namely when a Dirac point is formed, even extremely high levels of disorder are unable to localize the optical modes residing near the Dirac point. A comparative analysis of the key features of the propagation of Anderson modes formed in the Bragg gap or near the Dirac point is also presented. Our findings could provide valuable guidelines in assessing the influence of structural disorder on the functionality of a broad array of optical nanodevices.

  14. Exciting Molecules Close to the Rotational Quantum Resonance: Anderson Wall and Rotational Bloch Oscillations.

    PubMed

    Floß, Johannes; Averbukh, Ilya Sh

    2016-05-19

    We describe a universal behavior of linear molecules excited by a periodic train of short laser pulses under conditions close to the quantum resonance. The quantum resonance effect causes an unlimited ballistic growth of the angular momentum. We show that a disturbance of the quantum resonance, either by the centrifugal distortion of the rotating molecules or a controlled detuning of the pulse train period from the so-called rotational revival time, eventually halts the growth by causing Anderson localization beyond a critical value of the angular momentum, the Anderson wall. Below the wall, the rotational excitation oscillates with the number of pulses due to a mechanism similar to Bloch oscillations in crystalline solids. We suggest optical experiments capable of observing the rotational Anderson wall and Bloch oscillations at near-ambient conditions with the help of existing laser technology.

  15. John Anderson's development of (situational) realism and its bearing on psychology today.

    PubMed

    Hibberd, Fiona J

    2009-10-01

    In 1927, the Scottish philosopher John Anderson arrived in Australia to take up the chair of Philosophy at the University of Sydney. By the late 1930s, the "macrostructure" of his realist system was in place. It includes a theory of process and a substantial metaphysics, one that opposes positivism, linguistic philosophy and all forms of idealism. However, beyond Australia it remains largely unknown, despite its bearing on a number of current issues in psychology and the social sciences generally. This article outlines Anderson's transition from Hegelian idealism to realism, describes aspects of his ontology and epistemology, compares some of Anderson's ideas with Dewey's pragmatism and explains their relevance to present-day psychology.

  16. Image transport through a disordered optical fibre mediated by transverse Anderson localization.

    PubMed

    Karbasi, Salman; Frazier, Ryan J; Koch, Karl W; Hawkins, Thomas; Ballato, John; Mafi, Arash

    2014-02-25

    Transverse Anderson localization of light allows localized optical-beam-transport through a transversely disordered and longitudinally invariant medium. Its successful implementation in disordered optical fibres recently resulted in the propagation of localized beams of radii comparable to that of conventional optical fibres. Here we demonstrate optical image transport using transverse Anderson localization of light. The image transport quality obtained in the polymer disordered optical fibre is comparable to or better than some of the best commercially available multicore image fibres with less pixelation and higher contrast. It is argued that considerable improvement in image transport quality can be obtained in a disordered fibre made from a glass matrix with near wavelength-size randomly distributed air-holes with an air-hole fill-fraction of 50%. Our results open the way to device-level implementation of the transverse Anderson localization of light with potential applications in biological and medical imaging.

  17. "Bringing Taxonomy to the Service of Genetics": Edgar Anderson and Introgressive Hybridization.

    PubMed

    Kleinman, Kim

    2016-12-01

    In introgressive hybridization (the repeated backcrossing of hybrids with parental populations), Edgar Anderson found a source for variation upon which natural selection could work. In his 1953 review article "Introgressive Hybridization," he asserted that he was "bringing taxonomy to the service of genetics" whereas distinguished colleagues such as Theodosius Dobzhansky and Ernst Mayr did the precise opposite. His work as a geneticist particularly focused on linkage and recombination and was enriched by collaborations with Missouri Botanical Garden colleagues interested in taxonomy as well as with cytologists C.D. Darlington and Karl Sax. As the culmination of a biosystemtatic research program, Anderson's views challenged the mainstream of the Evolutionary Synthesis.

  18. Designed Assembly of Heterometallic Cluster Organic Frameworks Based on Anderson-Type Polyoxometalate Clusters.

    PubMed

    Li, Xin-Xiong; Wang, Yang-Xin; Wang, Rui-Hu; Cui, Cai-Yan; Tian, Chong-Bin; Yang, Guo-Yu

    2016-05-23

    A new approach to prepare heterometallic cluster organic frameworks has been developed. The method was employed to link Anderson-type polyoxometalate (POM) clusters and transition-metal clusters by using a designed rigid tris(alkoxo) ligand containing a pyridyl group to form a three-fold interpenetrated anionic diamondoid structure and a 2D anionic layer, respectively. This technique facilitates the integration of the unique inherent properties of Anderson-type POM clusters and cuprous iodide clusters into one cluster organic framework. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Wildlife Impact Assessment: Anderson Ranch, Black Canyon, and Boise Diversion Projects, Idaho. Final Report.

    SciTech Connect

    Meuleman, G. Allyn

    1986-05-01

    This report presents an analysis of impacts on wildlife and their habitats as a result of construction and operation of the US Bureau of Reclamation's Anderson Ranch, Black Canyon, and Boise Diversion Projects in Idaho. The objectives were to: (1) determine the probable impacts of development and operation of the Anderson Ranch, Black Canyon, and Boise Diversion Projects to wildlife and their habitats; (2) determine the wildlife and habitat impacts directly attributable to hydroelectric development and operation; (3) briefly identify the current major concerns for wildlife in the vicinities of the hydroelectric projects; and (4) provide for consultation and coordination with interested agencies, tribes, and other entities expressing interest in the project.

  20. View of Anderson removing the EAS during a session of EVA on Expedition 15

    NASA Image and Video Library

    2007-07-23

    ISS015-E-19135 (23 July 2007) --- Anchored to the Canadarm2 foot restraint, astronaut Clay Anderson, Expedition 15 flight engineer, removes the Early Ammonia Servicer (EAS) from its place on the International Space Station during a session of extravehicular activity (EVA). Anderson later jettisoned the EAS by shoving it opposite of the station's direction of travel. The EAS was installed on the P6 truss during STS-105 in August 2001, as an ammonia reservoir if a leak had occurred. It was never used, and was no longer needed after the permanent cooling system was activated last December. The blackness of space and Earth's horizon provide the backdrop for the scene.

  1. View of Anderson removing the EAS during a session of EVA on Expedition 15

    NASA Image and Video Library

    2007-07-23

    ISS015-E-19140 (23 July 2007) --- Anchored to the Canadarm2 foot restraint, astronaut Clay Anderson, Expedition 15 flight engineer, removes the Early Ammonia Servicer (EAS) from its place on the International Space Station during a session of extravehicular activity (EVA). Anderson later jettisoned the EAS by shoving it opposite of the station's direction of travel. The EAS was installed on the P6 truss during STS-105 in August 2001, as an ammonia reservoir if a leak had occurred. It was never used, and was no longer needed after the permanent cooling system was activated last December. The blackness of space and Earth's horizon provide the backdrop for the scene.

  2. Finite bias conductance of an Anderson level: a source--Liouville Hartree-Fock study.

    PubMed

    Ovchinnikov, Igor V; Neuhauser, Daniel

    2005-02-01

    We address the problem of stationary conductance through an Anderson spin-degenerate level at finite bias. Just as in the Anderson solution, for a finite bias in parameter space (bias, gate voltage, interaction constant, and the couplings to the leads) there exist spin-polarized and non-spin-polarized regions. The transition curve between them is found analytically for the case of symmetric coupling to the left and right leads. We approach the problem by a non-Markovian source-Liouville equation where the two-body interaction self-energies are taken in the Hartree-Fock approximation.

  3. Finite-size effects in Anderson localization of one-dimensional Bose-Einstein condensates

    SciTech Connect

    Cestari, J. C. C.; Foerster, A.; Gusmao, M. A.

    2010-12-15

    We investigate the disorder-induced localization transition in Bose-Einstein condensates for the Anderson and Aubry-Andre models in the noninteracting limit using exact diagonalization. We show that, in addition to the standard superfluid fraction, other tools such as the entanglement and fidelity can provide clear signatures of the transition. Interestingly, the fidelity exhibits good sensitivity even for small lattices. Effects of the system size on these quantities are analyzed in detail, including the determination of a finite-size-scaling law for the critical disorder strength in the case of the Anderson model.

  4. Interaction effect in the Kondo energy of the periodic Anderson-Hubbard model

    NASA Astrophysics Data System (ADS)

    Itai, K.; Fazekas, P.

    1996-07-01

    We extend the periodic Anderson model by switching on a Hubbard U for the conduction band. The nearly integral valent limit of the Anderson-Hubbard model is studied with the Gutzwiller variational method. The lattice Kondo energy shows U dependence both in the prefactor and the exponent. Switching on U reduces the Kondo scale, which can be understood to result from the blocking of hybridization. At half filling, we find a Brinkman-Rice-type transition from a Kondo insulator to a Mott insulator. Our findings should be relevant for a number of correlated two-band models of recent interest.

  5. Entanglement Area Law in Disordered Free Fermion Anderson Model in One, Two, and Three Dimensions

    DOE PAGES

    Pouranvari, Mohammad; Zhang, Yuhui; Yang, Kun

    2015-01-01

    We calculate numerically the entanglement entropy of free fermion ground states in one-, two-, and three-dimensional Anderson models and find that it obeys the area law as long as the linear size of the subsystem is sufficiently larger than the mean free path. This result holds in the metallic phase of the three-dimensional Anderson model, where the mean free path is finite although the localization length is infinite. Relation between the present results and earlier ones on area law violation in special one-dimensional models that support metallic phases is discussed.

  6. 77 FR 72906 - Chessie Logistics Co., LLC-Acquisition and Operation Exemption-J. Emil Anderson & Son, Inc.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-06

    ... Surface Transportation Board Chessie Logistics Co., LLC--Acquisition and Operation Exemption-- J. Emil... exemption under 49 CFR 1150.31 to acquire from J. Emil Anderson & Son, Inc. (Anderson) and to operate 1.006... it. See Mannheim Armitage Ry.--Acquis. & Operation Exemption--Certain Trackage Rights of J....

  7. Kondo correlations formation and the local magnetic moment dynamics in the Anderson model

    NASA Astrophysics Data System (ADS)

    Maslova, N. S.; Arseyev, P. I.; Mantsevich, V. N.

    2017-02-01

    We investigated the typical time scales of the Kondo correlations formation for the single-state Anderson model, when coupling to the reservoir is switched on at the initial time moment. The influence of the Kondo effect appearance on the system non-stationary characteristics was analyzed and discussed.

  8. View of Anderson posing for a photo in the A/L during Expedition 15

    NASA Image and Video Library

    2007-07-11

    ISS015-E-18168 (11 July 2007) --- With most of his body tucked away in a sleeping bag, astronaut Clay Anderson, Expedition 15 flight engineer, poses for a photo near two extravehicular mobility unit (EMU) spacesuits in the Quest Airlock of the International Space Station.

  9. High prevalence of subclinical hypothyroidism in patients with Anderson-Fabry disease.

    PubMed

    Hauser, A C; Gessl, A; Lorenz, M; Voigtländer, T; Födinger, M; Sunder-Plassmann, G

    2005-01-01

    Anderson-Fabry disease is a rare lysosomal storage disorder. It results from a deficiency of the lysosomal alpha-galactosidase A and leads to progressive accumulation of globotriaosylceramide in the endothelium and tissue cells of various organs. Some of the typical clinical findings such as tiredness, dry skin, myalgia and arthralgia as well as vague gastrointestinal complaints are also symptoms of hypothyroidism. Therefore, we studied the thyroid function in patients with Anderson-Fabry disease. Thyroid function was studied in 11 patients (6 female, 5 male) with Anderson-Fabry disease by measuring thyroid-stimulating hormone (TSH) and free thyroxine serum levels. Nine patients had chronic kidney disease with stage 1 and two with stage 5. Subclinical hypothyroidism (normal serum free thyroxine concentrations along with elevated serum TSH levels) was found in 4 of 11 patients (36.4%). Subclinical hypothyroidism was observed in both male and female patients as well as in patients with stage 1 and stage 5 kidney disease. Subclinical hypothyroidism is a common finding in patients with Anderson-Fabry disease, showing an excess prevalence as compared to the normal population. The high frequency seems to be relevant regarding the potential consequences of a hypothyroid state.

  10. ALONE, UNARMED, AND UNAFRAID OVER CUBA: THE STORY OF MAJOR RUDY ANDERSON

    DTIC Science & Technology

    2017-06-01

    Crisis. The thesis also examines the development of strategic reconnaissance in the Cold War, focusing on the first dedicated reconnaissance aircraft...ultimately in the larger context of the Cold War. vii CONTENTS Chapter Page...Anderson into a man who would fly missions alone, unarmed, and unafraid over Cuba at the height of the Cold War

  11. Comments in defense of symposia proceedings: Response to Bart and Anderson

    Treesearch

    Deborah M. Finch; A. Lorin Ward; R. H. Hamre

    1982-01-01

    A recent "Opinion" in the Wildlife Society Bulletin (Bart and Anderson 1981) made a case against publishing symposia proceedings because (1) papers of non-refereed symposia often lack credibility and, therefore, harm both the authors and the profession, (2) proceedings are not readily retrievable, and (3) some symposium reports are not appropriate for...

  12. Anderson uses laptop computer in the U.S. Laboratory during Joint Operations

    NASA Image and Video Library

    2007-06-13

    S117-E-07134 (12 June 2007) --- Astronaut Clayton Anderson, Expedition 15 flight engineer, uses a computer near the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station while Space Shuttle Atlantis (STS-117) was docked with the station. Astronaut Sunita Williams, flight engineer, is at right.

  13. 78 FR 41835 - Inflation Adjustments to the Price-Anderson Act Financial Protection Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-12

    ... Federal Regulations is sold by the Superintendent of Documents. #0;Prices of new books are listed in the... 3150-AJ25 Inflation Adjustments to the Price-Anderson Act Financial Protection Regulations AGENCY: Nuclear Regulatory Commission. ACTION: Final rule. SUMMARY: The Atomic Energy Act of 1954, as amended (AEA...

  14. Dystopian Visions of Global Capitalism: Philip Reeve's "Mortal Engines" and M.T Anderson's "Feed"

    ERIC Educational Resources Information Center

    Bullen, Elizabeth; Parsons, Elizabeth

    2007-01-01

    This article examines Philip Reeve's novel for children, "Mortal Engines", and M.T. Anderson's young adult novel, "Feed", by assessing these dystopias as prototypical texts of what Ulrich Beck calls risk society. Through their visions of a fictional future, the two narratives explore the hazards created by contemporary techno-economic progress,…

  15. M.D. Anderson, Ball cancer centers focus on research, care, prevention.

    PubMed

    Rees, Tom

    2004-01-01

    The folks at M.D. Anderson Cancer Center, Houston, win first place in this category with their traditionally excellent report. The Cancer Center at Ball Memorial Hospital, Muncie, Ind., receives the second place award with a report that uses unusual design elements to "shatter the myths" about cancer research.

  16. Community of Inquiry in e-Learning: A Critical Analysis of the Garrison and Anderson Model

    ERIC Educational Resources Information Center

    Jezegou, Annie

    2010-01-01

    This article is based on a constructively critical analysis of the "community of inquiry" model developed by Garrison and Anderson (2003) as part of their "e-learning" research. The authors claim that certain collaborative interactions create "distant presence" fostering the emergence of a "community of…

  17. Adolescent Identities and Sexual Behavior: An Examination of Anderson's Player Hypothesis

    ERIC Educational Resources Information Center

    Giordano, Peggy C.; Longmore, Monica A.; Manning, Wendy D.; Northcutt, Miriam J.

    2009-01-01

    We investigate the social and behavioral characteristics of male adolescents who self-identify as players, focusing particularly on Anderson's claim that this social role is inextricably linked with poverty and minority status. Results indicate that black respondents, those affiliated with liberal peers and young men who initially report a…

  18. Nonperturbative spectral-density function for the Anderson model at arbitrary temperatures

    NASA Technical Reports Server (NTRS)

    Neal, Henry L.

    1991-01-01

    Using a nonperturbative self-energy solution for the nondegenerate Anderson model, the temperature-dependent spectral-density function is calculated in the symmetric limit. The function is found to give reliable results for all values of the parameter u and inverse temperature beta.

  19. Melissa L. Anderson: APA/APAGS Award for Distinguished Graduate Student in Professional Psychology

    ERIC Educational Resources Information Center

    American Psychologist, 2012

    2012-01-01

    Presents a short biography of the winner of the American Psychological Association/American Psychological Association of Graduate Students Award for Distinguished Graduate Student in Professional Psychology. The 2012 winner is Melissa L. Anderson for her ongoing commitment to understanding, treating, and preventing domestic violence in Deaf women…

  20. Dystopian Visions of Global Capitalism: Philip Reeve's "Mortal Engines" and M.T Anderson's "Feed"

    ERIC Educational Resources Information Center

    Bullen, Elizabeth; Parsons, Elizabeth

    2007-01-01

    This article examines Philip Reeve's novel for children, "Mortal Engines", and M.T. Anderson's young adult novel, "Feed", by assessing these dystopias as prototypical texts of what Ulrich Beck calls risk society. Through their visions of a fictional future, the two narratives explore the hazards created by contemporary techno-economic progress,…

  1. Melissa L. Anderson: APA/APAGS Award for Distinguished Graduate Student in Professional Psychology

    ERIC Educational Resources Information Center

    American Psychologist, 2012

    2012-01-01

    Presents a short biography of the winner of the American Psychological Association/American Psychological Association of Graduate Students Award for Distinguished Graduate Student in Professional Psychology. The 2012 winner is Melissa L. Anderson for her ongoing commitment to understanding, treating, and preventing domestic violence in Deaf women…

  2. Combining Anderson's Model in the Teaching of Art Appreciation for Undergraduate Students

    ERIC Educational Resources Information Center

    Subramaniam, Maithreyi; Basaree, Ruzaika Omar; Hanafi, Jaffri; Putih, Abu Talib

    2016-01-01

    This study utilized 33 students taking creative communication design 3 in the third year of the graphic design and multimedia program, using an Anderson's model in teaching art appreciation. The quantitative research design and procedures were employed in this study. An experimental research using the quasi-experimental design, a single-group…

  3. 54. August 18, 1939 Oakland, California A.E. Anderson Taken during ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    54. August 18, 1939 Oakland, California A.E. Anderson Taken during trials on San Fransico Bay. Photograph taken for the U.S. Lighthouse Service. Currently in collection at Columbia River Maritime Museum. (Negative #67-133.3) - U.S. Coast Guard Cutter FIR, Puget Sound Area, Seattle, King County, WA

  4. Anderson working at the MELFI during STS-118/Expedition 15 Joint Operations

    NASA Image and Video Library

    2007-08-13

    S118-E-07456 (13 Aug. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, works with the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) in the Destiny laboratory of the International Space Station while Space Shuttle Endeavour (STS-118) remains docked with the station.

  5. View of Yurchikhin and Anderson posing for a photo in the SM during Expedition 15

    NASA Image and Video Library

    2007-09-04

    ISS015-E-27124 (4 Sept. 2007) --- Cosmonaut Fyodor N. Yurchikhin (left), Expedition 15 commander representing Russia's Federal Space Agency, and NASA astronaut Clay Anderson, flight engineer, pose for a photo in the Zvezda Service Module of the International Space Station.

  6. View of Expedition 15 FE Anderson performing the ANITA Experiment in the Node 1

    NASA Image and Video Library

    2007-10-06

    ISS015-E-32200 (6 Oct. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, uses an air sample pump and 2.5 liter gas sample bag to gather and analyze air samples for the Analyzing Interferometer for Ambient Air (ANITA) experiment in the Unity node of the International Space Station.

  7. E. N. Anderson: Caring for place: ecology, ideology, and emotion in traditional landscape management

    Treesearch

    Susan Stevens Hummel

    2016-01-01

    Anderson is deeply concerned with inadequate responses to ongoing global environmental degradation. Accordingly, he offers cases of traditional societies that survived over long time periods without destroying their environments. His focus is on ways humans think about plants, animals, and landscapes because of his conviction that stories about them are what make us...

  8. Results of a nationwide screening for Anderson-Fabry disease among dialysis patients.

    PubMed

    Kotanko, Peter; Kramar, Reinhard; Devrnja, Danijela; Paschke, Eduard; Voigtländer, Till; Auinger, Martin; Pagliardini, Severo; Spada, Marco; Demmelbauer, Klaus; Lorenz, Matthias; Hauser, Anna-Christine; Kofler, Hans-Jörg; Lhotta, Karl; Neyer, Ulrich; Pronai, Wolfgang; Wallner, Manfred; Wieser, Clemens; Wiesholzer, Martin; Zodl, Herbert; Födinger, Manuela; Sunder-Plassmann, Gere

    2004-05-01

    Anderson-Fabry disease is possibly underdiagnosed in patients with end-stage renal disease. Nationwide screening was therefore undertaken for Anderson-Fabry disease among dialysis patients in Austria. Screening for alpha-galactosidase A (AGAL) deficiency was performed by a blood spot test. In patients with a positive screening test, AGAL activity in leukocytes was determined. Individuals with decreased leukocyte AGAL activity were subjected to mutation testing in the GLA gene. Fifty (90.9%) of 55 Austrian hemodialysis centers participated in this study; 2480 dialysis patients (80.1% of the Austrian dialysis population) were screened. In 85 patients, the screening test was positive (85 of 2480, 3.42%; women, 3.32%; men, 3.50%). Among these 85 patients, 4 men (in 3 of whom Anderson-Fabry disease was already known before screening) had a severely decreased and 11 subjects had a borderline low AGAL activity. Genetic testing revealed mutations associated with Fabry disease in all four men with severely decreased AGAL activity resulting in a prevalence of 0.161% for the entire study population. A nationwide screening of dialysis patients permitted detection of a hitherto unknown man with Anderson-Fabry disease. The overall prevalence among dialysis patients was at least ten times higher as compared with recent registry data. Screening programs among patients with end-stage renal disease, especially men, should be put in place to identify families with Anderson-Fabry disease who probably may benefit from specific clinical care, and perhaps from enzyme replacement therapy. In dialysis patients, however, there is no evidence to support enzyme replacement therapy at present.

  9. Ginzburg-Landau expansion in strongly disordered attractive Anderson-Hubbard model

    NASA Astrophysics Data System (ADS)

    Kuchinskii, E. Z.; Kuleeva, N. A.; Sadovskii, M. V.

    2017-07-01

    We have studied disordering effects on the coefficients of Ginzburg-Landau expansion in powers of superconducting order parameter in the attractive Anderson-Hubbard model within the generalized DMFT+Σ approximation. We consider the wide region of attractive potentials U from the weak coupling region, where superconductivity is described by BCS model, to the strong coupling region, where the superconducting transition is related with Bose-Einstein condensation (BEC) of compact Cooper pairs formed at temperatures essentially larger than the temperature of superconducting transition, and a wide range of disorder—from weak to strong, where the system is in the vicinity of Anderson transition. In the case of semielliptic bare density of states, disorder's influence upon the coefficients A and B of the square and the fourth power of the order parameter is universal for any value of electron correlation and is related only to the general disorder widening of the bare band (generalized Anderson theorem). Such universality is absent for the gradient term expansion coefficient C. In the usual theory of "dirty" superconductors, the C coefficient drops with the growth of disorder. In the limit of strong disorder in BCS limit, the coefficient C is very sensitive to the effects of Anderson localization, which lead to its further drop with disorder growth up to the region of the Anderson insulator. In the region of BCS-BEC crossover and in BEC limit, the coefficient C and all related physical properties are weakly dependent on disorder. In particular, this leads to relatively weak disorder dependence of both penetration depth and coherence lengths, as well as of related slope of the upper critical magnetic field at superconducting transition, in the region of very strong coupling.

  10. Negative pressure wound therapy for Gustilo Anderson grade IIIb open tibial fractures

    PubMed Central

    Park, Chul Hyun; Shon, Oog Jin; Kim, Gi Beom

    2016-01-01

    Background: Traditionally, Gustilo Anderson grade IIIb open tibial fractures have been treated by initial wide wound debridement, stabilization of fracture with external fixation, and delayed wound closure. The purpose of this study is to evaluate the clinical and radiological results of staged treatment using negative pressure wound therapy (NPWT) for Gustilo Anderson grade IIIb open tibial fractures. Materials and Methods: 15 patients with Gustilo Anderson grade IIIb open tibial fractures, treated using staged protocol by a single surgeon between January 2007 and December 2011 were reviewed in this retrospective study. The clinical results were assessed using a Puno scoring system for severe open fractures of the tibia at the last followup. The range of motion (ROM) of the knee and ankle joints and postoperative complication were evaluated at the last followup. The radiographic results were assessed using time to bone union, coronal and sagittal angulations and a shortening at the last followup. Results: The mean score of Puno scoring system was 87.4 (range 67–94). The mean ROM of the knee and ankle joints was 121.3° (range 90°–130°) and 37.7° (range 15°–50°), respectively. Bone union developed in all patients and the mean time to union was 25.3 weeks (range 16–42 weeks). The mean coronal angulation was 2.1° (range 0–4°) and sagittal was 2.7° (range 1–4°). The mean shortening was 4.1 mm (range 0–8 mm). Three patients had partial flap necrosis and 1 patient had total flap necrosis. There was no superficial and deep wound infection. Conclusion: Staged treatment using NPWT decreased the risks of infection and requirement of flap surgeries in Gustilo Anderson grade IIIb open tibial fractures. Therefore, staged treatment using NPWT could be a useful treatment option for Gustilo Anderson grade IIIb open tibial fractures. PMID:27746498

  11. Wildlife Protection, Mitigation, and Enhancement Plans, Anderson Ranch and Black Canyon Facilities: Final Report.

    SciTech Connect

    Meuleman, G. Allyn

    1987-06-01

    Under direction of the Pacific Northwest Electric Power Planning and Conservation Act of 1980, and the subsequent Northwest Power Planning Council's Columbia River Basin Fish and Wildlife Program, projects have been developed in Idaho to mitigate the impacts to wildlife habitat and production due to the development and operation of the Anderson Ranch and Black Canyon Facilities (i.e., dam, power plant, and reservoir areas). The Anderson Ranch Facility covered about 4812 acres of wildlife habitat while the Black Canyon Facility covered about 1115 acres. These acreages include dam and power plant staging areas. A separate mitigation plan has been developed for each facility. A modified Habitat Evaluation Procedure (HEP) was used to assess the benefits of the mitigation plans to wildlife. The interagency work group used the target species Habitat Units (HU's) lost at each facility as a guideline during the mitigation planning process, while considering the needs of wildlife in the areas. Totals of 9619 and 2238 target species HU's were estimated to be lost in the Anderson Ranch and Black Canyon Facility areas, respectively. Through a series of projects, the mitigation plans will provide benefits of 9620 target species HU's to replace Anderson Ranch wildlife impacts and benefits of 2195 target species HU's to replace Black Canyon wildlife impacts. Target species to be benefited by the Anderson Ranch and/or Black Canyon mitigation plans include the mallard, Canada goose, mink, yellow warbler, black-capped chickadee, ruffed grouse, mule deer, blue grouse, sharp-tailed grouse, ring-necked pheasant, and peregrine falcon.

  12. Evidence of Non-Mean-Field-Like Low-Temperature Behavior in the Edwards-Anderson Spin-Glass Model

    NASA Astrophysics Data System (ADS)

    Yucesoy, B.; Katzgraber, Helmut G.; Machta, J.

    2012-10-01

    The three-dimensional Edwards-Anderson and mean-field Sherrington-Kirkpatrick Ising spin glasses are studied via large-scale Monte Carlo simulations at low temperatures, deep within the spin-glass phase. Performing a careful statistical analysis of several thousand independent disorder realizations and using an observable that detects peaks in the overlap distribution, we show that the Sherrington-Kirkpatrick and Edwards-Anderson models have a distinctly different low-temperature behavior. The structure of the spin-glass overlap distribution for the Edwards-Anderson model suggests that its low-temperature phase has only a single pair of pure states.

  13. Quantum phase transitions in the bosonic single-impurity Anderson model

    NASA Astrophysics Data System (ADS)

    Lee, H.-J.; Bulla, R.

    2007-04-01

    We consider a quantum impurity model in which a bosonic impurity level is coupled to a non-interacting bosonic bath, with the bosons at the impurity site subject to a local Coulomb repulsion U. Numerical renormalization group calculations for this bosonic single-impurity Anderson model reveal a zero-temperature phase diagram where Mott phases with reduced charge fluctuations are separated from a Bose-Einstein condensed phase by lines of quantum critical points. We discuss possible realizations of this model, such as atomic quantum dots in optical lattices. Furthermore, the bosonic single-impurity Anderson model appears as an effective impurity model in a dynamical mean-field theory of the Bose-Hubbard model.

  14. On 'Credo 2004' as viewed under the 'development-context' model of Colin Anderson.

    PubMed

    Cohn, M

    2006-08-01

    In analysing the Zinkernagel and Hengartner's 'Credo 2004,' Anderson introduces his 'development-context model' for the immunity-tolerance discrimination. He compares this model with the 'geographical model of Credo 2004' and our 'time-based two-signal model'. The discussion here deals with the advantages and limitations of the Anderson model considered largely at the level of principle. A meaningful discussion requires that we agree on the principle which separates the pathway of the effector output into two decision steps, the sorting of the repertoire and the regulation of effector class. The mechanism for the sorting of the repertoire is what might be referred to as the Self-Nonself discrimination. The black box approach, antigen-in, effector response-out, is what is referred to as the immunity-tolerance discrimination which includes the sorting of the repertoire. If this point of principle is accepted then we are left with a 'time-based two signal default model'.

  15. Experimental observation of Anderson localization in laser-kicked molecular rotors

    NASA Astrophysics Data System (ADS)

    Bitter, Martin; Milner, Valery

    2016-05-01

    For the first time, the phenomenon of Anderson localization is observed and studied in a system of true quantum kicked rotors. Nitrogen molecules in a supersonic molecular jet are cooled down to 27 K and are rotationally excited by a periodic train of 24 high-intensity femtosecond pulses. Exponential distribution of the molecular angular momentum - the most unambiguous signature of Anderson localization - is measured directly by means of coherent Raman scattering. We demonstrate the suppressed growth of the molecular rotational energy with the number of laser kicks and study the dependence of the localization length on the kick strength. Both timing and amplitude noise in the pulse train is shown to destroy the localization and revive the diffusive growth of angular momentum.

  16. The exhaustion problem in the periodic Anderson model: An X-boson approach

    NASA Astrophysics Data System (ADS)

    Franco, R.; Silva-Valencia, J.; Figueira, M. S.

    2006-10-01

    We study the thermodynamical properties of the periodic Anderson model (PAM), within the X-boson approach. The exhaustion problem is studied and we calculate the entropy and the specific heat for the heavy fermion Kondo regime (HF-K) of the PAM. We compute numerically the evolution of the Kondo lattice TKL and the Fermi liquid T* temperatures as function of the conduction electron occupation number nc. The results obtained are consistent with others reported in the literature for the Kondo lattice.

  17. Magnetic frustration in the three-band Anderson lattice model for high-temperature superconductors

    SciTech Connect

    Ihle, D.; Kasner, M. )

    1990-09-01

    The three-band Anderson lattice model for the CuO{sub 2} planes in high-{Tc} superconductors is established. Treating this model by perturbation theory, the effective spin interactions are derived. The antiferromagnetic superexchange integrals are calculated as functions of the direct oxygen transfer and the hole concentration. It is found that frustration in the superexchange occurs, even in the undoped case, which increases with oxygen trnasfer and decreases with hole concentration.

  18. Anderson works with the TRAC experiment in the U.S. Laboratory during Joint Operations

    NASA Image and Video Library

    2007-06-12

    S117-E-07031 (12 June 2007) --- Astronaut Clayton Anderson, Expedition 15 flight engineer, works with the Test of Reaction and Adaptation Capabilities (TRAC) experiment in the Destiny laboratory of the International Space Station while Space Shuttle Atlantis was docked with the station. The TRAC investigation will test the theory of brain adaptation during space flight by testing hand-eye coordination before, during and after the space flight.

  19. Critical properties of the Anderson localization transition and the high-dimensional limit

    NASA Astrophysics Data System (ADS)

    Tarquini, E.; Biroli, G.; Tarzia, M.

    2017-03-01

    In this paper we present a thorough study of transport, spectral, and wave-function properties at the Anderson localization critical point in spatial dimensions d =3 , 4, 5, 6. Our aim is to analyze the dimensional dependence and to assess the role of the d →∞ limit provided by Bethe lattices and treelike structures. Our results strongly suggest that the upper critical dimension of Anderson localization is infinite. Furthermore, we find that dU=∞ is a much better starting point compared to dL=2 to describe even three-dimensional systems. We find that critical properties and finite-size scaling behavior approach by increasing d those found for Bethe lattices: the critical state becomes an insulator characterized by Poisson statistics and corrections to the thermodynamics limit become logarithmic in the number N of lattice sites. In the conclusion, we present physical consequences of our results, propose connections with the nonergodic delocalized phase suggested for the Anderson model on infinite-dimensional lattices, and discuss perspectives for future research studies.

  20. Topological Anderson insulator phase in a Dirac-semimetal thin film

    NASA Astrophysics Data System (ADS)

    Chen, Rui; Xu, Dong-Hui; Zhou, Bin

    2017-06-01

    The recently discovered topological Dirac semimetal represents a new exotic quantum state of matter. Topological Dirac semimetals can be viewed as three-dimensional analogues of graphene, in which the Dirac nodes are protected by crystalline symmetry. It has been found that the quantum confinement effect can gap out Dirac nodes and convert Dirac semimetal to a band insulator. The band insulator is either a normal insulator or quantum spin Hall insulator, depending on the thin-film thickness. We present the study of disorder effects in a thin film of Dirac semimetals. It is found that moderate Anderson disorder strength can drive a topological phase transition from a normal band insulator to a topological Anderson insulator in a Dirac-semimetal thin film. The numerical calculation based on the model parameters of Dirac semimetal Na3Bi shows that in the topological Anderson insulator phase, a quantized conductance plateau occurs in the bulk gap of the band insulator, and the distributions of local currents further confirm that the quantized conductance plateau arises from the helical edge states induced by disorder. Finally, an effective medium theory based on the Born approximation fits the numerical data.

  1. Electronic structure of vitamin B12 within the framework of the Haldane-Anderson impurity model

    NASA Astrophysics Data System (ADS)

    Kandemir, Zafer; Mayda, Selma; Bulut, Nejat

    2015-03-01

    We study the electronic structure of vitamin B12 (cyanocobalamine C63H88CoN14O14P) by using the framework of the multi-orbital single-impurity Haldane-Anderson model of a transition-metal impurity in a semiconductor host. Here, our purpose is to understand the many-body effects originating from the transition-metal impurity. In this approach, the cobalt 3 d orbitals are treated as the impurity states placed in a semiconductor host which consists of the rest of the molecule. The parameters of the resulting effective Haldane-Anderson model are obtained within the Hartree-Fock approximation for the electronic structure of the molecule. The quantum Monte Carlo technique is then used to calculate the one-electron and magnetic correlation functions of this effective Haldane-Anderson model for vitamin B12. We find that new states form inside the semiconductor gap due to the on-site Coulomb interaction at the impurity 3 d orbitals and that these states become the highest occupied molecular orbitals. In addition, we present results on the charge distribution and spin correlations around the Co atom. We compare the results of this approach with those obtained by the density-functional theory calculations.

  2. Effect of Anderson localization on light emission from gold nanoparticle aggregates

    PubMed Central

    Abdellatif, Mohamed H; Abdelrasoul, Gaser N; Liakos, Ioannis; Scarpellini, Alice; Marras, Sergio; Diaspro, Alberto

    2016-01-01

    The localization of light known as Anderson localization is a common phenomenon characterizing aggregates of metallic nanostructures. The electromagnetic energy of visible light can be localized inside nanostructures below the diffraction limit by converting the optical modes into nonradiative surface plasmon resonances. The energy of the confined photons is correlated to the size and shape of the nanostructured system. In this work, we studied the photoluminescence dependence of aggregates of 14 nm diameter gold nanoparticles (AuNPs) synthesized by drop-casting a liquid suspension on two different substrates of glass and quartz. The AuNP aggregates were characterized by electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The dielectric constant of the surrounding medium plays a crucial role in determining the aggregate geometry, which affects the Anderson localization of light in the aggregates and hence causes a red-shift in the plasmonic resonance and in the photoluminescence emission. The geometry of the gold nanoparticle aggregates determine the strength of the Anderson localization, and hence, the light emission from the aggregates. The photoluminescence lifetime was found to be dependent on the AuNP aggregate geometry and the dielectric constant of the medium. PMID:28144549

  3. The Anderson Mine (Arizona)--An early diagenetic uranium deposit in Miocene Lake Sediments

    SciTech Connect

    Mueller, A.; Halbach, P.

    1983-03-01

    The Anderson mine is located in Yavapai County, West-Central Arizona, an area forming part of the Basin and Range province. The uranium deposit occurs in the Miocene Chapin Wash Formation, a sequence of interbedded lacustrine and alluvial sediments. Uranium mineralization is confined to the lacustrine facies of Chapin Wash sediments, composed of tuffaceous mudstones, fine-grained sandstones, and silicified marlstones. South of the Anderson mine outcrop zone, the lacustrine sequence reaches an average thickness of 150 m, including two basal carbonaceous horizons of 37 and 35 m in thickness. Uranium is locally associated with high values of Mo, As, and V. In drill core samples, highgrade mineralization (up to 2.2% U) is confined to individual seams of lignitic coal, forms halos around rootlet remains, and fills burrows or irregular fractures. Spotlike concentrations are associated with framboidal pyrite spheres. Uranyl-bearing opaline silica and colloform coffinite have been identified as main ore minerals. Uranium was preconcentrated during early diagenesis by sorption onto colloidal humic substance, silica gel, and zeolites. Subsequent precipitation as coffinite was mainly controlled by bacteriogenic H/sub 2/S gas. At present, both mineralized carbonaceous horizons are in a state of radiogenic equilibrium. Uranium mineralization was displaced by late Miocene to early Pliocene tectonic movements along Basin and Range normal faults. The Anderson mine may be classified as a strata-bound, low-temperature deposit in lacustrine sediments formed by complex sorption and precipitation processes in an early diagenetic environment.

  4. Anderson localization of electrons in single crystals: LixFe7Se8

    PubMed Central

    Ying, Tianping; Gu, Yueqiang; Chen, Xiao; Wang, Xinbo; Jin, Shifeng; Zhao, Linlin; Zhang, Wei; Chen, Xiaolong

    2016-01-01

    Anderson (disorder-induced) localization, proposed more than half a century ago, has inspired numerous efforts to explore the absence of wave diffusions in disordered media. However, the proposed disorder-induced metal-insulator transition (MIT), associated with the nonpropagative electron waves, has hardly been observed in three-dimensional (3D) crystalline materials, let alone single crystals. We report the observation of an MIT in centimeter-size single crystals of LixFe7Se8 induced by lattice disorder. Both specific heat and infrared reflectance measurements reveal the presence of considerable electronic states in the vicinity of the Fermi level when the MIT occurs, suggesting that the transition is not due to Coulomb repulsion mechanism. The 3D variable range hopping regime evidenced by electrical transport measurements at low temperatures indicates the localized nature of the electronic states on the Fermi level. Quantitative analyses of carrier concentration, carrier mobility, and simulated density of states (DOS) fully support that LixFe7Se8 is an Anderson insulator. On the basis of these results, we provide a unified DOS picture to explain all the experimental results, and a schematic diagram for finding other potential Anderson insulators. This material will thus serve as a rich playground for both theoretical and experimental investigations on MITs and disorder-induced phenomena. PMID:26989781

  5. Analysis of the characteristics of patients with open tibial fractures of Gustilo and Anderson type III☆

    PubMed Central

    Jaña Neto, Frederico Carlos; de Paula Canal, Marina; Alves, Bernardo Aurélio Fonseca; Ferreira, Pablício Martins; Ayres, Jefferson Castro; Alves, Robson

    2016-01-01

    Objective To analyze the characteristics of patients with Gustilo–Anderson Type III open tibial fractures treated at a tertiary care hospital in São Paulo between January 2013 and August 2014. Methods This was a cross-sectional retrospective study. The following data were gathered from the electronic medical records: age; gender; diagnosis; trauma mechanism; comorbidities; associated fractures; Gustilo and Anderson, Tscherne and AO classifications; treatment (initial and definitive); presence of compartment syndrome; primary and secondary amputations; MESS (Mangled Extremity Severity Score) index; mortality rate; and infection rate. Results 116 patients were included: 81% with fracture type IIIA, 12% IIIB and 7% IIIC; 85% males; mean age 32.3 years; and 57% victims of motorcycle accidents. Tibial shaft fractures were significantly more prevalent (67%). Eight patients were subjected to amputation: one primary case and seven secondary cases. Types IIIC (75%) and IIIB (25%) predominated among the patients subjected to secondary amputation. The MESS index was greater than 7 in 88% of the amputees and in 5% of the limb salvage group. Conclusion The profile of patients with open tibial fracture of Gustilo and Anderson Type III mainly involved young male individuals who were victims of motorcycle accidents. The tibial shaft was the segment most affected. Only 7% of the patients underwent amputation. Given the current controversy in the literature about amputation or salvage of severely injured lower limbs, it becomes necessary to carry out prospective studies to support clinical decisions. PMID:27069881

  6. Kondo physics of the Anderson impurity model by distributional exact diagonalization

    NASA Astrophysics Data System (ADS)

    Motahari, S.; Requist, R.; Jacob, D.

    2016-12-01

    The distributional exact diagonalization (DED) scheme is applied to the description of Kondo physics in the Anderson impurity model. DED maps Anderson's problem of an interacting impurity level coupled to an infinite bath onto an ensemble of finite Anderson models, each of which can be solved by exact diagonalization. An approximation to the self-energy of the original infinite model is then obtained from the ensemble-averaged self-energy. Using Friedel's sum rule, we show that the particle number constraint, a central ingredient of the DED scheme, ultimately imposes Fermi liquid behavior on the ensemble-averaged self-energy, and thus is essential for the description of Kondo physics within DED. Using the numerical renormalization group (NRG) method as a benchmark, we show that DED yields excellent spectra, both inside and outside the Kondo regime for a moderate number of bath sites. Only for very strong correlations (U /Γ ≫10 ) does the number of bath sites needed to achieve good quantitative agreement become too large to be computationally feasible.

  7. Abrupt physical and chemical changes during 1992-1999, Anderson Springs, SE Geyser Geothermal Field, California

    USGS Publications Warehouse

    Janik, Cathy J.; Goff, Fraser; Walter, Stephen R.; Sorey, Michael L.; Counce, Dale; Colvard, Elizabeth M.

    2000-01-01

    The Anderson Springs area is located about 90 miles (145 kilometers) north of San Francisco, California, in the southwestern part of Lake County. The area was first developed in the late 1800s as a health resort, which was active until the 1930s. Patrons drank a variety of cool to hot mineral waters from improved springs, swam in various baths and pools, and hiked in the rugged hills flanking Anderson Creek and its tributaries. In the bluffs to the south of the resort were four small mercury mines of the eastern Mayacmas quicksilver district. About 1,260 flasks of mercury were produced from these mines between 1909 and 1943. By the early 1970s, the higher ridges south and west of Anderson Springs became part of the southeast sector of the greater Geysers geothermal field. Today, several electric power plants are built on these ridges, producing energy from a vapor-dominated 240 °C reservoir. Only the main hot spring at Anderson Springs has maintained a recognizable identity since the 1930s. The hot spring is actually a cluster of seeps and springs that issue from a small fault in a ravine southwest of Anderson Creek. Published and unpublished records show that the maximum temperature (Tm) of this cluster fell gradually from 63°C in 1889 to 48°C in 1992. However, Tm of the cluster climbed to 77°C in 1995 and neared boiling (98°C) in 1998. A new cluster of boiling vents and small fumaroles (Tm = 99.3°C) formed in 1998 about 30 m north of the old spring cluster. Several evergreen trees on steep slopes immediately above these vents apparently were killed by the new activity. Thermal waters at Anderson Hot Springs are mostly composed of near-surface ground waters with some added gases and condensed steam from The Geysers geothermal system. Compared to gas samples from Southeast Geysers wells, the hot spring gases are higher in CO2 and lower in H2S and NH3. As the springs increased in temperature, however, the gas composition became more like the mean composition

  8. Anderson-Mott transition in a disordered Hubbard chain with correlated hopping

    NASA Astrophysics Data System (ADS)

    Battista, Francesca; Camjayi, Alberto; Arrachea, Liliana

    2017-07-01

    We study the ground-state phase diagram of the Anderson-Hubbard model with correlated hopping at half-filling in one dimension. The Hamiltonian has a local Coulomb repulsion U and a disorder potential with local energies randomly distributed in the interval (-W ,+W ) with equal probability, acting on the singly occupied sites. The hopping process which modifies the number of doubly occupied sites is forbidden. The hopping between nearest-neighbor singly occupied and empty sites or between singly occupied and doubly occupied sites has the same amplitude t . We identify three different phases as functions of the disorder amplitude W and Coulomb interaction strength U >0 . When U <4 t the system shows a metallic phase: (i) only when no disorder is present W =0 or an Anderson-localized phase, (ii) when disorder is introduced W ≠0 . When U >4 t the Anderson-localized phase survives as long as disorder effects dominate on the interaction effects, otherwise a Mott-insulator phase (iii) arises. Phases (i) and (ii) are characterized by a finite density of doublons and a vanishing charge gap among the ground state and the excited states. Phase (iii) is characterized by the vanishing density of doublons and a finite gap for the charge excitations.

  9. Unprecedented χ isomers of single-side triol-functionalized Anderson polyoxometalates and their proton-controlled isomer transformation.

    PubMed

    Zhang, Jiangwei; Liu, Zhenhua; Huang, Yichao; zhang, Jin; Hao, Jian; Wei, Yongge

    2015-06-04

    The μ2-O atom in Anderson polyoxometalates was regioselectively activated by the introduction of protons, which, upon functionalization with triol ligands, could afford a series of unique χ isomers of the organically-derived Anderson cluster {[RCC(CH2O)3]MMo6O18(OH)3}(3-). Herein proton-controlled isomer transformation between the δ and χ isomer was observed by using the fingerprint region in the IR spectra and (13)C NMR spectra.

  10. Thermochemical cycles

    NASA Technical Reports Server (NTRS)

    Funk, J. E.; Soliman, M. A.; Carty, R. H.; Conger, W. L.; Cox, K. E.; Lawson, D.

    1975-01-01

    The thermochemical production of hydrogen is described along with the HYDRGN computer program which attempts to rate the various thermochemical cycles. Specific thermochemical cycles discussed include: iron sulfur cycle; iron chloride cycle; and hybrid sulfuric acid cycle.

  11. Conduction in quasiperiodic and quasirandom lattices: Fibonacci, Riemann, and Anderson models

    NASA Astrophysics Data System (ADS)

    Varma, V. K.; Pilati, S.; Kravtsov, V. E.

    2016-12-01

    We study the ground state conduction properties of noninteracting electrons in aperiodic but nonrandom one-dimensional models with chiral symmetry and make comparisons against Anderson models with nondeterministic disorder. The first model we consider is the Fibonacci lattice, which is a paradigmatic model of quasicrystals; the second is the Riemann lattice, which we define inspired by Dyson's proposal on the possible connection between the Riemann hypothesis and a suitably defined quasicrystal. Our analysis is based on Kohn's many-particle localization tensor defined within the modern theory of the insulating state. In the Fibonacci quasicrystal, where all single-particle eigenstates are critical (i.e., intermediate between ergodic and localized), the noninteracting electron gas is found to be an insulator, due to spectral gaps, at various specific fillings ρ , including the values ρ =1 /gn , where g is the golden ratio and n is any integer; however away from these spectral anomalies, the system is found to be a conductor, including the half-filled case. In the Riemann lattice metallic behavior is found at half filling as well; however, in contrast to the Fibonacci quasicrystal, the Riemann lattice is generically an insulator due to single-particle eigenstate localization, likely at all other fillings. Its behavior turns out to be alike that of the off-diagonal Anderson model, albeit with different system-size scaling of the band-center anomalies. The advantages of analyzing the Kohn's localization tensor instead of other measures of localization familiar from the theory of Anderson insulators (such as the participation ratio or the Lyapunov exponent) are highlighted.

  12. Causation's nuclear future: applying proportional liability to the Price-Anderson Act.

    PubMed

    O'Connell, William D

    2014-11-01

    For more than a quarter century, public discourse has pushed the nuclear-power industry in the direction of heavier regulation and greater scrutiny, effectively halting construction of new reactors. By focusing on contemporary fear of significant accidents, such discourse begs the question of what the nation's court system would actually do should a major nuclear incident cause radiation-induced cancers. Congress's attempt to answer that question is the Price-Anderson Act, a broad statute addressing claims by the victims of a major nuclear accident. Lower courts interpreting the Act have repeatedly encountered a major stumbling block: it declares that judges must apply the antediluvian preponderance-of-the-evidence logic of state tort law, even though radiation science insists that the causes of radiation-induced cancers are more complex. After a major nuclear accident, the Act's paradoxically outdated rules for adjudicating "causation" would make post-incident compensation unworkable. This Note urges that nuclear-power-plant liability should not turn on eighteenth-century tort law. Drawing on modern scientific conclusions regarding the invariably "statistical" nature of cancer, this Note suggests a unitary federal standard for the Price-Anderson Act--that a defendant be deemed to have "caused" a plaintiff's injury in direct proportion to the increased risk of harm the defendant has imposed. This "proportional liability" rule would not only fairly evaluate the costs borne by injured plaintiffs and protect a reawakening nuclear industry from the prospect of bank-breaking litigation, but would prove workable with only minor changes to the Price-Anderson Act's standards of "injury" and "fault."

  13. Causation's nuclear future: applying proportional liability to the Price-Anderson Act.

    PubMed

    O'Connell, William D

    2014-11-01

    For more than a quarter century, public discourse has pushed the nuclear-power industry in the direction of heavier regulation and greater scrutiny, effectively halting construction of new reactors. By focusing on contemporary fear of significant accidents, such discourse begs the question of what the nation's court system would actually do should a major nuclear incident cause radiation-induced cancers. Congress's attempt to answer that question is the Price-Anderson Act, a broad statute addressing claims by the victims of a major nuclear accident. Lower courts interpreting the Act have repeatedly encountered a major stumbling block: it declares that judges must apply the antediluvian preponderance-of-the-evidence logic of state tort law, even though radiation science insists that the causes of radiation-induced cancers are more complex. After a major nuclear accident, the Act's paradoxically outdated rules for adjudicating "causation" would make post-incident compensation unworkable. This Note urges that nuclear-power-plant liability should not turn on eighteenth-century tort law. Drawing on modern scientific conclusions regarding the invariably "statistical" nature of cancer, this Note suggests a unitary federal standard for the Price-Anderson Act--that a defendant be deemed to have "caused" a plaintiff's injury in direct proportion to the increased risk of harm the defendant has imposed. This "proportional liability" rule would not only fairly evaluate the costs borne by injured plaintiffs and protect a reawakening nuclear industry from the prospect of bank-breaking litigation, but would prove workable with only minor changes to the Price-Anderson Act's standards of "injury" and "fault."

  14. Anderson-Hynes pyeloplasty: are we all really on the same page?

    PubMed

    Adam, Ahmed; Smith, Grahame H H

    2016-03-01

    The Anderson-Hynes pyeloplasty (AHP) is a surgical technique used in the management of pelvi-ureteric junction obstruction. This operation has been performed for over six decades and has etched its name in the annals of urology. But are we all really referring to the same procedure? A systematic review of the Ovid MEDLINE(R) and Ovid OLDMEDLINE(R) database from 1946 to 20 June 2014 was performed for the terms 'Anderson and Hynes' and 'Anderson-Hynes', with later restriction to the title of journal article. Each respective author's descriptive images (figures/photographic) of technique performed was compared with the original procedure. Non-English figure legends were translated using online translational tools. In total, 242 articles were retrieved. Streamlining this search to articles with the above search terms restricted to article title revealed 58 (34 English/24 non-English) articles. Only 29/58 papers had referenced the original procedure. Operative images were present in 17/58 of the articles claiming to have performed the AHP. Within these papers, only 7/17 articles depicted both the L-shaped cut and pelvic flap. Diverse variations were observed in the remainder 10/17 articles. This was a worldwide phenomenon, observed more commonly in recent decades and when minimally invasive techniques were used. The AHP is often not performed as was originally described. Over the decades, surgeons have unknowingly attributed variations to this procedure. Based on this review, a novel 'geometric classification' system has been proposed to better define the dismembered pyeloplasty. © 2015 Royal Australasian College of Surgeons.

  15. Data Center Energy Efficiency and Renewable Energy Site Assessment: Anderson Readiness Center; Salem, Oregon

    SciTech Connect

    Metzger, I.; Van Geet, O.

    2014-06-01

    This report summarizes the results from the data center energy efficiency and renewable energy site assessment conducted for the Oregon Army National Guard in Salem, Oregon. A team led by NREL conducted the assessment of the Anderson Readiness Center data centers March 18-20, 2014 as part of ongoing efforts to reduce energy use and incorporate renewable energy technologies where feasible. Although the data centers in this facility account for less than 5% of the total square footage, they are estimated to be responsible for 70% of the annual electricity consumption.

  16. The cumulant expansion of the periodic Anderson model; completeness and the ?-derivable approximation

    NASA Astrophysics Data System (ADS)

    Figueira, M. S.; Foglio, M. E.

    1996-07-01

    The approximate Green's functions of the localized electrons, obtained by the cumulant expansion of the periodic Anderson model in the limit of infinite Coulomb repulsion, do not satisfy completeness even for the simplest families of diagrams, like the chain approximation. The idea that employing 0953-8984/8/27/012/img6-derivable approximations would solve this difficulty is shown to be false by proving that the chain approximation is 0953-8984/8/27/012/img6-derivable and does not satisfy completeness. After finding a family of diagrams with Green's functions that satisfy completeness, we put forward a conjecture that shows how to select families of diagrams with this property.

  17. Anderson transition in low-dimensional disordered systems driven by long-range nonrandom hopping.

    PubMed

    Rodríguez, A; Malyshev, V A; Sierra, G; Martín-Delgado, M A; Rodríguez-Laguna, J; Domínguez-Adame, F

    2003-01-17

    The single-parameter scaling hypothesis predicts the absence of delocalized states for noninteracting quasiparticles in low-dimensional disordered systems. We show analytically, using a supersymmetric method combined with a renormalization group analysis, as well as numerically that extended states may occur in the one- and two-dimensional Anderson model with a nonrandom hopping falling off as some power of the distance between sites. The different size scaling of the bare level spacing and the renormalized magnitude of the disorder seen by the quasiparticles finally results in the delocalization of states at one of the band edges of the quasiparticle energy spectrum.

  18. STS-118 Astronaut Williams and Expedition 15 Engineer Anderson Perform EVA

    NASA Technical Reports Server (NTRS)

    2007-01-01

    As the construction continued on the International Space Station (ISS), STS-118 Astronaut Dave Williams, representing the Canadian Space Agency, participated in the fourth and final session of Extra Vehicular Activity (EVA). During the 5 hour space walk, Williams and Expedition 15 engineer Clay Anderson (out of frame) installed the External Wireless Instrumentation System Antenna, attached a stand for the shuttle robotic arm extension boom, and retrieved the two Materials International Space Station Experiments (MISSE) for return to Earth. MISSE collects information on how different materials weather in the environment of space.

  19. Machine learning for many-body physics: The case of the Anderson impurity model

    SciTech Connect

    Arsenault, Louis-François; Lopez-Bezanilla, Alejandro; von Lilienfeld, O. Anatole; Millis, Andrew J.

    2014-10-31

    We applied machine learning methods in order to find the Green's function of the Anderson impurity model, a basic model system of quantum many-body condensed-matter physics. Furthermore, different methods of parametrizing the Green's function are investigated; a representation in terms of Legendre polynomials is found to be superior due to its limited number of coefficients and its applicability to state of the art methods of solution. The dependence of the errors on the size of the training set is determined. Our results indicate that a machine learning approach to dynamical mean-field theory may be feasible.

  20. View of Anderson working in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-08-30

    ISS015-E-25424 (30 Aug. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, works the controls of the station's robotic arm, Canadarm2, in the Destiny laboratory of the International Space Station during Pressurized Mating Adapter-3 (PMA-3) transfer operations. Using the Canadarm2, the PMA-3 was undocked from the Unity node's left side at 7:18 a.m. (CDT) and docked to Unity's lower port at 8:07 a.m. to prepare for the arrival of Node 2, the Harmony module, on the STS-120 flight of Space Shuttle Discovery in October 2007.

  1. Destruction of Anderson localization in quantum nonlinear Schrödinger lattices.

    PubMed

    Milovanov, Alexander V; Iomin, Alexander

    2017-04-01

    The four-wave interaction in quantum nonlinear Schrödinger lattices with disorder is shown to destroy the Anderson localization of waves, giving rise to unlimited spreading of the nonlinear field to large distances. Moreover, the process is not thresholded in the quantum domain, contrary to its "classical" counterpart, and leads to an accelerated spreading of the subdiffusive type, with the dispersion 〈(Δn)^{2}〉∼t^{1/2} for t→+∞. The results, presented here, shed light on the origin of subdiffusion in systems with a broad distribution of relaxation times.

  2. Ferrimagnetism and single-particle excitations in a periodic Anderson model on the honeycomb lattice

    NASA Astrophysics Data System (ADS)

    Seki, Kazuhiro; Shirakawa, Tomonori; Zhang, Qinfang; Li, Tao; Yunoki, Seiji

    2015-04-01

    By using the variationalcluster approximation and cluster perturbation theory, we investigate the magnetism and single-particle excitations of a periodic Anderson model on the honeycomb lattice as an effective model for the single-side hydrogenated graphene, namely, graphone. We calculate the magnetic moment as a function of U (Coulomb interaction on impurity sites) with showing that the ground state is ferrimagneticfor any U > 0. We then calculate the single-particle excitations and show that the single-particle excitations are gapless and exhibit quadratic dispersion relation near the Fermi energy.

  3. View of Anderson setting up SAME Hardware in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-09-01

    ISS015-E-26252 (1 Sept. 2007) --- Astronaut Clay Anderson, Expedition 15 flight engineer, works on the Smoke and Aerosol Measurement Experiment (SAME) hardware setup located in the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station. SAME will measure the smoke properties, or particle size distribution, of typical particles that are produced from different materials that can be found onboard station and other spacecrafts. SAME aims to test the performance of ionization smoke detectors and evaluate the performance of the photoelectric smoke detectors. The data will be used to develop a model that can predict smoke droplet growth that will be used to evaluate future smoke detection devices.

  4. View of Anderson working with SAME Hardware in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-09-08

    ISS015-E-27411 (8 Sept. 2007) --- NASA astronaut Clay Anderson, Expedition 15 flight engineer, works on the Smoke and Aerosol Measurement Experiment (SAME) hardware located in the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station. SAME will measure the smoke properties, or particle size distribution, of typical particles that are produced from different materials that can be found onboard station and other spacecrafts. SAME aims to test the performance of ionization smoke detectors and evaluate the performance of the photoelectric smoke detectors. The data will be used to develop a model that can predict smoke droplet growth that will be used to evaluate future smoke detection devices.

  5. View of Anderson working with SAME Hardware in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-09-08

    ISS015-E-27425 (8 Sept. 2007) --- NASA astronaut Clay Anderson, Expedition 15 flight engineer, works on the Smoke and Aerosol Measurement Experiment (SAME) hardware located in the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station. SAME will measure the smoke properties, or particle size distribution, of typical particles that are produced from different materials that can be found onboard station and other spacecrafts. SAME aims to test the performance of ionization smoke detectors and evaluate the performance of the photoelectric smoke detectors. The data will be used to develop a model that can predict smoke droplet growth that will be used to evaluate future smoke detection devices.

  6. Critical exponent for the Anderson transition in the three-dimensional orthogonal universality class

    NASA Astrophysics Data System (ADS)

    Slevin, Keith; Ohtsuki, Tomi

    2014-01-01

    We report a careful finite size scaling study of the metal-insulator transition in Anderson's model of localization. We focus on the estimation of the critical exponent ν that describes the divergence of the localization length. We verify the universality of this critical exponent for three different distributions of the random potential: box, normal and Cauchy. Our results for the critical exponent are consistent with the measured values obtained in experiments on the dynamical localization transition in the quantum kicked rotor realized in a cold atomic gas.

  7. Machine learning for many-body physics: The case of the Anderson impurity model

    NASA Astrophysics Data System (ADS)

    Arsenault, Louis-François; Lopez-Bezanilla, Alejandro; von Lilienfeld, O. Anatole; Millis, Andrew J.

    2014-10-01

    Machine learning methods are applied to finding the Green's function of the Anderson impurity model, a basic model system of quantum many-body condensed-matter physics. Different methods of parametrizing the Green's function are investigated; a representation in terms of Legendre polynomials is found to be superior due to its limited number of coefficients and its applicability to state of the art methods of solution. The dependence of the errors on the size of the training set is determined. The results indicate that a machine learning approach to dynamical mean-field theory may be feasible.

  8. DMFT Study for Valence Fluctuations in the Extended Periodic Anderson Model

    NASA Astrophysics Data System (ADS)

    Shinzaki, Ryu; Nasu, Joji; Koga, Akihisa

    2016-02-01

    We study valence fluctuations at finite temperatures in the extended periodic Anderson model, where the Coulomb interaction between conduction and localized f-electrons is taken into account, using dynamical mean-field theory combined with the continuous-time quantum Monte Carlo (CT-QMC) method. The valence transition with the hysteresis is clearly found, indicating the first-order phase transition between the Kondo and mixed-valence states. We demonstrate that spin correlation rapidly develops when the system approaches the valence transition point. The comparison of the impurity solvers, the CT-QMC, non-crossing approximation, and one-crossing approximation, is also addressed.

  9. [Varroa destructor (Anderson and Trueman, 2000); the change in classification within the genus Varroa (Oudemans, 1904)].

    PubMed

    Topolska, G

    2001-01-01

    Varroa jacobsoni was noted for the first time in 1904, in the nest ofApis cerana. In Apis mellifera nests the first Varroa mites were probably found in Korea (1950), next in Japan (1958). In the following years they have spread all over the world. All the time they were regarded as V. jacobsoni. Recently Anderson and Trueman have proved that Varroa jacobsoni is more than one species. They gave the new name Varroa destructor n. sp. to the group of six haplotypes. Mites, which became pests ofA. mellifera worldwide, belong to V. destructor.

  10. Anderson works on the NUTRITION Experiment in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-06-25

    ISS015-E-13670 (25 June 2007) --- Astronaut Clayton Anderson, Expedition 15 flight engineer, works with the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods. The results of the Nutrition experiment will be used to better understand the time course effects of space flight on human physiology.

  11. Anderson works on the NUTRITION Experiment in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-06-25

    ISS015-E-13695 (25 June 2007) --- Astronaut Clayton Anderson, Expedition 15 flight engineer, works with the Minus Eighty Degree Laboratory Freezer for ISS (MELFI) as part of the Nutritional Status Assessment (NUTRITION) experiment in the Destiny laboratory of the International Space Station. MELFI is a low temperature freezer facility with nominal operating temperatures of -80, -26 and +4 degrees Celsius that will preserve experiment materials over long periods. The results of the Nutrition experiment will be used to better understand the time course effects of space flight on human physiology.

  12. SHORTER MENSTRUAL CYCLES ASSOCIATED WITH CHLORINATION BY-PRODUCTS IN DRINKING WATER

    EPA Science Inventory

    Shorter Menstrual Cycles Associated with Chlorination by-Products in Drinking Water.
    Gayle Windham, Kirsten Waller, Meredith Anderson, Laura Fenster, Pauline Mendola, Shanna Swan. California Department of Health Services.

    In previous studies of tap water consumption we...

  13. CHLORINATION BY-PRODUCTS IN DRINKING WATER AND MENSTRUAL CYCLE FUNCTION

    EPA Science Inventory

    Chlorination by-Products in Drinking Water and Menstrual Cycle Function

    Gayle C. Windham1, Kirsten Waller2, Meredith Anderson2, Laura Fenster1, Pauline Mendola3, Shanna Swan4

    1California Department of Health Services, Division of Environmental and Occupational Disea...

  14. CHLORINATION BY-PRODUCTS IN DRINKING WATER AND MENSTRUAL CYCLE FUNCTION

    EPA Science Inventory

    Chlorination by-Products in Drinking Water and Menstrual Cycle Function

    Gayle C. Windham1, Kirsten Waller2, Meredith Anderson2, Laura Fenster1, Pauline Mendola3, Shanna Swan4

    1California Department of Health Services, Division of Environmental and Occupational Disea...

  15. SHORTER MENSTRUAL CYCLES ASSOCIATED WITH CHLORINATION BY-PRODUCTS IN DRINKING WATER

    EPA Science Inventory

    Shorter Menstrual Cycles Associated with Chlorination by-Products in Drinking Water.
    Gayle Windham, Kirsten Waller, Meredith Anderson, Laura Fenster, Pauline Mendola, Shanna Swan. California Department of Health Services.

    In previous studies of tap water consumption we...

  16. Physical, chemical, and isotopic data for samples from the Anderson Springs area, Lake County, California, 1998-1999

    USGS Publications Warehouse

    Janik, C.J.; Goff, F.; Sorey, M.L.; Rytuba, J.J.; Counce, D.; Colvard, E.M.; Huebner, M.; White, L.D.; Foster, A.

    1999-01-01

    Anderson Springs is located about 90 miles (145 kilometers) north of San Francisco, California, in the southwestern part of Lake County. The area was first developed in the late 1800s as a health resort, which was active until the 1930s. In the rugged hills to the south of the resort were four small mercury mines of the eastern Mayacmas quicksilver district. About 1,260 flasks of mercury were produced from these mines between 1909 and 1943. In the 1970s, the high-elevation areas surrounding Anderson Springs became part of The Geysers geothermal field. Today, several electric powerplants are located on the ridges above Anderson Springs, utilizing steam produced from a 240°C vapor-dominated reservoir. The primary purpose of this report is to provide physical, chemical, and isotopic data on samples collected in the Anderson Springs area during 1998 and 1999, in response to a Freedom of Information Act request. In July 1998, drainage from the Schwartz adit of the abandoned Anderson mercury mine increased substantially over a 2-day period, transporting a slurry of water and precipitates down a tributary and into Anderson Creek. In August 1998, J.J. Rytuba and coworkers sampled the Schwartz adit drainage and water from the Anderson Springs Hot Spring for base metal and methylmercury analysis. They measured a maximum temperature (Tm) of 85°C in the Hot Spring. Published records show that the temperature of the Anderson Springs Hot Spring (main spring) was 63°C in 1889, 42–52°C from 1974 through 1991, and 77°C in March 1995. To investigate possible changes in thermal spring activity and to collect additional samples for geochemical analysis, C.J. Janik and coworkers returned to the area in September and December 1998. They determined that a cluster of springs adjacent to the main spring had Tm=98°C, and they observed that a new area of boiling vents and small fumaroles (Tm=99.3°C) had formed in an adjacent gully about 20 meters to the north of the main spring

  17. The atomic approach to the Anderson model for the finite U case: application to a quantum dot.

    PubMed

    Lobo, T; Figueira, M S; Foglio, M E

    2010-07-09

    In the present work we apply the atomic approach to the single-impurity Anderson model (SIAM). A general formulation of this approach, that can be applied both to the impurity and to the lattice Anderson Hamiltonian, was developed in a previous work (Foglio et al 2009 arxiv: 0903.0139v2 [cond-mat.str-el]). The method starts from the cumulant expansion of the periodic Anderson model, employing the hybridization as a perturbation. The atomic Anderson limit is analytically solved and its sixteen eigenenergies and eigenstates are obtained. This atomic Anderson solution, which we call the AAS, has all the fundamental excitations that generate the Kondo effect, and in the atomic approach is employed as a 'seed' to generate the approximate solutions for finite U. The width of the conduction band is reduced to zero in the AAS, and we choose its position such that the Friedel sum rule is satisfied, close to the chemical potential mu. We perform a complete study of the density of states of the SIAM over the whole relevant range of parameters: the empty dot, intermediate valence, Kondo and magnetic regimes. In the Kondo regime we obtain a density of states that characterizes well the structure of the Kondo peak. To show the usefulness of the method we have calculated the conductance of a quantum dot, side-coupled to a conduction band.

  18. [Portuguese validation of the symptom inventory of the M.D. Anderson Cancer Center].

    PubMed

    Kolankiewicz, Adriane Cristina Bernat; Domenico, Edvane Birelo Lopes De; Lopes, Luís Felipe Dias; Magnago, Tânia Solange Bosi de Souza

    2014-12-01

    To analyze the reliability and validity of the psychometric properties of the Brazilian version of the instrument for symptom assessment, titled MD Anderson Symptom Inventory - core. A cross-sectional study with 268 cancer patients in outpatient treatment, in the municipality of Ijuí, state of Rio Grande do Sul, Brazil. The Cronbach's alpha for the MDASI general, symptoms and interferences was respectively (0.857), (0.784) and (0.794). The factor analysis showed adequacy of the data (0.792). In total, were identified four factors of the principal components related to the symptoms. Factor I: sleep problems, distress (upset), difficulties in remembering things and sadness. Factor II: dizziness, nausea, lack of appetite and vomiting. Factor III: drowsiness, dry mouth, numbness and tingling. Factor IV: pain, fatigue and shortness of breath. A single factor was revealed in the component of interferences with life (0.780), with prevalence of activity in general (59.7%), work (54.9%) and walking (49.3%). The Brazilian version of the MD Anderson Symptom Inventory - core showed adequate psychometric properties in the studied population.

  19. Electronic structure and correlations of vitamin B12 studied within the Haldane-Anderson impurity model

    NASA Astrophysics Data System (ADS)

    Kandemir, Zafer; Mayda, Selma; Bulut, Nejat

    2016-04-01

    We study the electronic structure and correlations of vitamin B12 (cyanocobalamine) by using the framework of the multi-orbital single-impurity Haldane-Anderson model of a transition-metal impurity in a semiconductor host. The parameters of the effective Haldane-Anderson model are obtained within the Hartree-Fock (HF) approximation. The quantum Monte Carlo (QMC) technique is then used to calculate the one-electron and magnetic correlation functions of this effective model. We observe that new states form inside the semiconductor gap found by HF due to the intra-orbital Coulomb interaction at the impurity 3d orbitals. In particular, the lowest unoccupied states correspond to an impurity bound state, which consists of states from mainly the CN axial ligand and the corrin ring as well as the Co eg-like orbitals. We also observe that the Co (3d) orbitals can develop antiferromagnetic correlations with the surrounding atoms depending on the filling of the impurity bound states. In addition, we make comparisons of the HF+QMC data with the density functional theory calculations. We also discuss the photoabsorption spectrum of cyanocobalamine.

  20. Statistics of Anderson-localized modes in disordered photonic crystal slab waveguides

    NASA Astrophysics Data System (ADS)

    Vasco, J. P.; Hughes, S.

    2017-06-01

    We present a fully three-dimensional Bloch mode expansion technique and a photon Green function formalism to compute the quality factors, mode volumes, and Purcell enhancement distributions of a disordered W1 photonic crystal slab waveguide in the slow-light Anderson-localization regime. By considering fabrication (intrinsic) and intentional (extrinsic) disorder we find that the Purcell enhancement statistics are well described by log-normal distributions without any fitting parameters. We also compare directly the effects of hole size fluctuations as well as fluctuations in the hole position. The functional dependence of the mean and standard deviation of the quality factor and Purcell enhancement distributions is found to decrease exponentially with the square root of the extrinsic disorder parameter. The strong coupling probability between a single quantum dot and an Anderson-localized mode is numerically computed and found to exponentially decrease with the squared extrinsic disorder parameter, where low disordered systems give rise to larger probabilities when state-of-the-art quantum dots are considered. The optimal spatial regions to position quantum dots in the W1 waveguide are also discussed. These theoretical results are fundamentally interesting for disordered photonics and connect to recent experimental works on photonic crystal slab waveguides in the slow-light regime. Our three-dimensional slab results also contradict some previous findings that use simpler two-dimensional models to understand these complex planar systems.

  1. Spectral Approach to Anderson Localization in a Disordered 2D Complex Plasma Crystal

    NASA Astrophysics Data System (ADS)

    Kostadinova, Eva; Liaw, Constanze; Matthews, Lorin; Busse, Kyle; Hyde, Truell

    2016-10-01

    In condensed matter, a crystal without impurities acts like a perfect conductor for a travelling wave-particle. As the level of impurities reaches a critical value, the resistance in the crystal increases and the travelling wave-particle experiences a transition from an extended to a localized state, which is called Anderson localization. Due to its wide applicability, the subject of Anderson localization has grown into a rich field in both physics and mathematics. Here, we introduce the mathematics behind the spectral approach to localization in infinite disordered systems and provide physical interpretation in context of both quantum mechanics and classical physics. We argue that the spectral analysis is an important contribution to localization theory since it avoids issues related to the use of boundary conditions, scaling, and perturbation. To test accuracy and applicability we apply the spectral approach to the case of a 2D hexagonal complex plasma crystal used as a macroscopic analog for a graphene-like medium. Complex plasma crystals exhibit characteristic distance and time scales, which are easily observable by video microscopy. As such, these strongly coupled many-particle systems are ideal for the study of localization phenomena. The goal of this research is to both expand the spectral method into the classical regime and show the potential of complex plasma as a macroscopic tool for localization experiments. NSF / DOE funding is gratefully acknowledged - PHY1414523 & PHY1262031.

  2. Simulation of Anderson localization in two-dimensional ultracold gases for pointlike disorder

    NASA Astrophysics Data System (ADS)

    Morong, W.; DeMarco, B.

    2015-08-01

    Anderson localization has been observed for a variety of media, including ultracold atomic gases with speckle disorder in one and three dimensions. However, observation of Anderson localization in a two-dimensional geometry for ultracold gases has been elusive. We show that a cause of this difficulty is the relatively high percolation threshold of a speckle potential in two dimensions, resulting in strong classical localization. We propose a realistic pointlike disorder potential that circumvents this percolation limit with localization lengths that are experimentally observable. The percolation threshold is evaluated for experimentally realistic parameters, and a regime of negligible classical trapping is identified. Localization lengths are determined via scaling theory, using both exact scattering cross sections and the Born approximation, and by direct simulation of the time-dependent Schrödinger equation. We show that the Born approximation can underestimate the localization length by four orders of magnitude at low energies, while exact cross sections and scaling theory provide an upper bound. Achievable experimental parameters for observing localization in this system are proposed.

  3. Observations of nighttime winds using pilot balloons in Anderson Creek Valley, Geysers, California

    SciTech Connect

    Nappo, C.J.; Snodgrass, H.F.

    1981-06-01

    Nighttime drainage or downslope winds along the east-facing slope of Anderson Creek Valley located in the Geysers area of northern California are examined using pilot balloons as air parcel tracers. Observations made over four nights show a persistent pattern of winds. Before sunset strong westerly winds blow into the valley. These winds are believed due to the late afternoon sea breeze. Drainage winds become fully developed within 2 h after sunset. The drainage wind has an average speed of approx.3 m s/sup -1/ regardless of the speed of the ambient wind. The drainage layer thickness grows at a rate of approx.80 m per kilometer of downwind distance. Balloons in the drainage current quickly spread throughout the shallow, sidewall canyon containing Anderson Creek. The transition from the local valley wind system to the free, ambient wind occurs at about ridge height, i.e., /sub 5/00 m above the valley basin, for weak ambient winds, and at /sub 3/00 m above the valley basin for strong ambient winds.

  4. Solving a puzzle in the Anderson transition with long-range correlated potentials

    NASA Astrophysics Data System (ADS)

    Petersen, Greg; Sandler, Nancy

    2013-03-01

    The conditions for an Anderson transition in 1D systems has been an open question since it's discovery a half century ago. Although scaling theory predicts localization in this case, it has been shown that a transition exists in the presence of some form of long-range correlations in the on-site energies. One of the most widely used examples are disorder potentials generated by 1 /kα spectral densities that, with an appropriate short range cutoff, result in vanishing correlation functions in the thermodynamic limit. However, these results are in direct contradiction to work by Kotani et. al. that argues for the existence of a metallic state only when infinite range correlations are non-zero. In this talk we will show that there is no contradiction between the two results as the correlation function generated from numerical techniques is staunchly different from analytic expectations. Furthermore, we will present the exact analytic expression for the correlation function in the thermodynamic limit. Finally, we will discuss the role played by short- and long-range features of the correlation function in the Anderson transition. Supported by NSF-MWN/CIAM and NSF-PIRE.

  5. Fabrication and characterization of disordered polymer optical fibers for transverse Anderson localization of light.

    PubMed

    Karbasi, Salman; Frazier, Ryan J; Mirr, Craig R; Koch, Karl W; Mafi, Arash

    2013-07-29

    We develop and characterize a disordered polymer optical fiber that uses transverse Anderson localization as a novel waveguiding mechanism. The developed polymer optical fiber is composed of 80,000 strands of poly (methyl methacrylate) (PMMA) and polystyrene (PS) that are randomly mixed and drawn into a square cross section optical fiber with a side width of 250 μm. Initially, each strand is 200 μm in diameter and 8-inches long. During the mixing process of the original fiber strands, the fibers cross over each other; however, a large draw ratio guarantees that the refractive index profile is invariant along the length of the fiber for several tens of centimeters. The large refractive index difference of 0.1 between the disordered sites results in a small localized beam radius that is comparable to the beam radius of conventional optical fibers. The input light is launched from a standard single mode optical fiber using the butt-coupling method and the near-field output beam from the disordered fiber is imaged using a 40X objective and a CCD camera. The output beam diameter agrees well with the expected results from the numerical simulations. The disordered optical fiber presented in this work is the first device-level implementation of 2D Anderson localization, and can potentially be used for image transport and short-haul optical communication systems.

  6. Anderson-Mott transition in arrays of a few dopant atoms in a silicon transistor.

    PubMed

    Prati, Enrico; Hori, Masahiro; Guagliardo, Filippo; Ferrari, Giorgio; Shinada, Takahiro

    2012-07-01

    Dopant atoms are used to control the properties of semiconductors in most electronic devices. Recent advances such as single-ion implantation have allowed the precise positioning of single dopants in semiconductors as well as the fabrication of single-atom transistors, representing steps forward in the realization of quantum circuits. However, the interactions between dopant atoms have only been studied in systems containing large numbers of dopants, so it has not been possible to explore fundamental phenomena such as the Anderson-Mott transition between conduction by sequential tunnelling through isolated dopant atoms, and conduction through thermally activated impurity Hubbard bands. Here, we observe the Anderson-Mott transition at low temperatures in silicon transistors containing arrays of two, four or six arsenic dopant atoms that have been deterministically implanted along the channel of the device. The transition is induced by controlling the spacing between dopant atoms. Furthermore, at the critical density between tunnelling and band transport regimes, we are able to change the phase of the electron system from a frozen Wigner-like phase to a Fermi glass by increasing the temperature. Our results open up new approaches for the investigation of coherent transport, band engineering and strongly correlated systems in condensed-matter physics.

  7. Towards the Realization of Self-Consistent Effective Medium Theory for Anderson Disorder Model

    NASA Astrophysics Data System (ADS)

    Ekuma, Chinedu; Terletska, Hanna; Tam, Ka Ming; Meng, Zi Yang; Moreno, Juana; Jarrell, Mark

    2014-03-01

    A mean-field theory that properly characterizes the Anderson localization transition in three dimensions has remain elusive. Here, we present a systematic typical medium dynamical cluster approximation that provides a proper description of this phenomenon. Our method accurately provides a proper way to treat the different energy scales (close to the criticality) such that the characteristic re-entrant behavior of the mobility edge is obtained. This allows us to study the localization in different momenta cells, which renders the discovery that the Anderson localization transition occurs in a momentum cell-selective fashion. As a function of cluster size, our method systematically recovers the re-entrance behavior of the mobility edge and obtains the correct critical disorder strength with great improvement on the critical exponent of the order parameter (β > 1 . 4). This work is supported by the NSF EPSCoR EPS-1003897; and DOE BES DE-AC02-98CH10886 and SciDAC DE-SC0005274. Supercomputer support is provided by LONI and HPC@LSU.

  8. Nutritional influences on early white matter development: response to Anderson and Burggren.

    PubMed

    Deoni, Sean C L; Dean, Douglas C; Walker, Lindsay; Dirks, Holly; O'Muircheartaigh, Jonathan

    2014-10-15

    Does breastfeeding alter early brain development? In a recent retrospective study, our group examined the cross-sectional relationship between early infant feeding practice and white matter maturation and cognitive development. In groups matched for child and mother age, gestation duration, birth weight, gender distribution, and socio-economic status; we observed that children who were breastfed exclusively for at least 3 months showed, on average, increased white matter myelin development compared to children who either were exclusively formula-fed, or received a mixture of breast milk and formula. In secondary analysis on sub-sets of these children, again matched for important confounding variables, we found improved cognitive test scores of receptive language in the exclusively breast-fed children compared to formula or formula+breast-fed children; and that prolonged breastfeeding was associated with increased motor, language, and visual functioning in exclusively breast-fed children. In response to this work, Anderson and Burggren have questioned our methodology and, by association, our findings. Further, they use their critique as a platform for advancing an alternative interpretation of our findings: that observed results were not associated with prolonged breast-feeding, but rather delayed the introduction of cow's milk. In this response, we address and clarify some of the misconceptions presented by Anderson and Burggren.

  9. Anderson Localization and the Quantum Phase Diagram of Three Dimensional Disordered Dirac Semimetals

    NASA Astrophysics Data System (ADS)

    Pixley, J. H.; Goswami, Pallab; Das Sarma, S.

    2015-08-01

    We study the quantum phase diagram of a three dimensional noninteracting Dirac semimetal in the presence of either quenched axial or scalar potential disorder, by calculating the average and the typical density of states as well as the inverse participation ratio using numerically exact methods. We show that as a function of the disorder strength a half-filled (i.e., undoped) Dirac semimetal displays three distinct ground states, namely an incompressible semimetal, a compressible diffusive metal, and a localized Anderson insulator, in stark contrast to a conventional dirty metal that only supports the latter two phases. We establish the existence of two distinct quantum critical points, which respectively govern the semimetal-metal and the metal-insulator quantum phase transitions and also reveal their underlying multifractal nature. Away from half-filling the (doped) system behaves as a diffusive metal that can undergo Anderson localization only, which is shown by determining the mobility edge and the phase diagram in terms of energy and disorder.

  10. Analysis of Anderson Acceleration on a Simplified Neutronics/Thermal Hydraulics System

    SciTech Connect

    Toth, Alex; Kelley, C. T.; Slattery, Stuart R; Hamilton, Steven P; Clarno, Kevin T; Pawlowski, R. P. P.

    2015-01-01

    ABSTRACT A standard method for solving coupled multiphysics problems in light water reactors is Picard iteration, which sequentially alternates between solving single physics applications. This solution approach is appealing due to simplicity of implementation and the ability to leverage existing software packages to accurately solve single physics applications. However, there are several drawbacks in the convergence behavior of this method; namely slow convergence and the necessity of heuristically chosen damping factors to achieve convergence in many cases. Anderson acceleration is a method that has been seen to be more robust and fast converging than Picard iteration for many problems, without significantly higher cost per iteration or complexity of implementation, though its effectiveness in the context of multiphysics coupling is not well explored. In this work, we develop a one-dimensional model simulating the coupling between the neutron distribution and fuel and coolant properties in a single fuel pin. We show that this model generally captures the convergence issues noted in Picard iterations which couple high-fidelity physics codes. We then use this model to gauge potential improvements with regard to rate of convergence and robustness from utilizing Anderson acceleration as an alternative to Picard iteration.

  11. Dr Walter Henry Anderson (1870-1937) and the mission hospital at Safed, Palestine.

    PubMed

    Stokes, Gordon S

    2013-02-01

    Walter Henry Anderson, a brewer's clerk in Burton-upon-Trent, became a missionary doctor, supported by a society promoting welfare and evangelism in Jewish communities abroad. His family background was rich in pastoral ministry at home and adventure abroad. Arguably, this background played a part in his decision to serve the Jews of Safed. His life in Palestine entailed much enterprise and hardship as he raised a family, fought disease and set up a mission hospital serving not only the Jewish community but persons of all faiths. His years in Palestine, from 1894 to 1915, were times of peace in the Middle East before the turmoil unleashed by the Great War. Jews from the Diaspora were gaining an increasing foothold in Palestine, their 'Promised Land'. Themes of that era - the rise of Zionism, confrontation between Judaism and evangelical Christianity, conflict between immigrant Jew and Palestinian Arab and the remarkable travels of Lawrence of Arabia were interwoven with the lives of Dr Anderson and his family.

  12. Evidence of Non-Mean-Field-Like Low-Temperature Behavior in the Edwards-Anderson Spin-Glass Model

    NASA Astrophysics Data System (ADS)

    Yucesoy, Burcu; Katzgraber, Helmut G.; Machta, Jonathan

    2013-03-01

    The three and four-dimensional Edwards-Anderson and mean-field Sherrington-Kirkpatrick Ising spin glasses are studied via large-scale Monte Carlo simulations at low temperatures, deep within the spin-glass phase. Performing a careful statistical analysis of several thousand independent disorder realizations and using an observable that detects peaks in the overlap distribution, we show that the Sherrington-Kirkpatrick and Edwards-Anderson models have a distinctly different low-temperature behavior. The structure of the spin-glass overlap distribution for the Edwards-Anderson model suggests that its low-temperature phase has only a single pair of pure states. J. M. and B. Y. are supported in part by the NSF (Grant No. DMR-0907235 and DMR-1208046).

  13. Level compressibility for the Anderson model on regular random graphs and the eigenvalue statistics in the extended phase

    NASA Astrophysics Data System (ADS)

    Metz, Fernando L.; Castillo, Isaac Pérez

    2017-08-01

    We calculate the level compressibility χ (W ,L ) of the energy levels inside [-L /2 ,L /2 ] for the Anderson model on infinitely large random regular graphs with on-site potentials distributed uniformly in [-W /2 ,W /2 ] . We show that χ (W ,L ) approaches the limit limL→0+χ (W ,L ) =0 for a broad interval of the disorder strength W within the extended phase, including the region of W close to the critical point for the Anderson transition. These results strongly suggest that the energy levels follow the Wigner-Dyson statistics in the extended phase, consistent with earlier analytical predictions for the Anderson model on an Erdös-Rényi random graph. Our results are obtained from the accurate numerical solution of an exact set of equations valid for infinitely large regular random graphs.

  14. Anderson Insulators in Self-Assembled Gold Nanoparticles Thin Films: Single Electron Hopping between Charge Puddles Originated from Disorder.

    PubMed

    Jiang, Cheng-Wei; Ni, I-Chih; Hsieh, Yun-Lien; Tzeng, Shien-Der; Wu, Cen-Shawn; Kuo, Watson

    2017-06-12

    The Anderson insulating states in Au nanoparticle assembly are identified and studied under the application of magnetic fields and gate voltages. When the inter-nanoparticle tunneling resistance is smaller than the quantum resistance, the system showing zero Mott gap can be insulating at very low temperature. In contrast to Mott insulators, Anderson insulators exhibit great negative magnetoresistance, inferring charge delocalization in a strong magnetic field. When probed by the electrodes spaced by ~200 nm, they also exhibit interesting gate-modulated current similar to the multi-dot single electron transistors. These results reveal the formation of charge puddles due to the interplay of disorder and quantum interference at low temperatures.

  15. A Theoretical Analysis of Anderson Acceleration and Its Application in Multiphysics Simulation for Light-Water Reactors

    NASA Astrophysics Data System (ADS)

    Toth, Alexander Raymond

    In this work, we are concerned with both contributing to the theoretical foundation for Anderson acceleration, a method for accelerating the convergence rate of Picard iteration, and evaluating its performance in the context of coupled multiphysics problems in nuclear reactor simulation. Anderson acceleration proceeds by maintaining a depth of previous iterate information in order to compute a new iterate as a linear combination of previous evaluations of the fixed-point map, where the linear combination coefficients are obtained by solving a linear leastsquares problem. Prior to this work, theory for this method was fairly sparse, dealing mainly with showing its relation to quasi-Newton multisecant updating and, when applied to linear problems, GMRES iteration. The analysis presented in this work significantly expands upon the theory for this method. As this method is intended as an acceleration method for Picard iteration, our analysis concerns problems for which Picard iteration is convergent, namely when the fixed-point mapping is contractive. We present analysis which represent the first convergence results for limited-memory variations of Anderson acceleration and for nonlinear problems. Additionally, we present analysis for several variations on the standard Anderson acceleration method. In particular, we consider a variation which adjusts the memory utilization in order to maintain good conditioning of the least-squares problem, and we present local improvement results for the case in which the fixed-point map can only be evaluated approximately. With respect to coupled multiphysics problems, we examine Anderson acceleration as an alternative to Picard iteration in the context of black-box code coupling in nuclear reactor simulation. Picard iteration comes with several drawbacks in this context, namely relatively slow convergence and poor robustness. To test the potential for Anderson acceleration to improve upon the weaknesses of Picard iteration, we first

  16. Patriot Games: Yes, Indeed, the British Are Coming! But M. T. Anderson's Revolutionary War Novel Is Unlike Anything You've Ever Read

    ERIC Educational Resources Information Center

    Horning, Kathleen

    2006-01-01

    This article presents an interview with 38-year-old writer Matthew Tobin Anderson. In the interview, Anderson talks about his experiences, passion for writing, teenage interests, and his relation to the distinguished writer Mark Twain. He also states the importance of liberty and what it takes to be a patriot and a loyalist. Furthermore, Matthew…

  17. Patriot Games: Yes, Indeed, the British Are Coming! But M. T. Anderson's Revolutionary War Novel Is Unlike Anything You've Ever Read

    ERIC Educational Resources Information Center

    Horning, Kathleen

    2006-01-01

    This article presents an interview with 38-year-old writer Matthew Tobin Anderson. In the interview, Anderson talks about his experiences, passion for writing, teenage interests, and his relation to the distinguished writer Mark Twain. He also states the importance of liberty and what it takes to be a patriot and a loyalist. Furthermore, Matthew…

  18. Tunable Anderson metal-insulator transition in quantum spin-Hall insulators

    NASA Astrophysics Data System (ADS)

    Chen, Chui-Zhen; Liu, Haiwen; Jiang, Hua; Sun, Qing-feng; Wang, Ziqiang; Xie, X. C.

    2015-06-01

    We numerically study disorder effects in the Bernevig-Hughes-Zhang (BHZ) model, and we find that the Anderson transition of a quantum spin-Hall insulator (QSHI) is determined by model parameters. The BHZ Hamiltonian is equivalent to two decoupled spin blocks that belong to the unitary class. In contrast to the common belief that a two-dimensional unitary system scales to an insulator except at certain critical points, we find, through calculations scaling properties of the localization length, level statistics, and participation ratio, that a possible exotic metallic phase emerges between the QSHI and normal insulator phases in the InAs/GaSb-type BHZ model. On the other hand, direct transition from a QSHI to a normal insulator is found in the HgTe/CdTe-type BHZ model. Furthermore, we show that the metallic phase originates from the Berry phase and can survive both inside and outside the gap.

  19. Second-order perturbation theory for the single-impurity Anderson model of a BCS superconductor

    NASA Astrophysics Data System (ADS)

    Alastalo, Ari T.

    2017-09-01

    This paper presents a conserving approximation for a single magnetic impurity embedded in a BCS superconductor according to the Anderson model. The calculation generalizes the second-order selfenergy theory of a normal metal host into a superconducting medium. Within the second-order theory, both spin and pairing fluctuations contribute to the selfenergy. The second-order theory removes the unphysical spontaneous symmetry breaking of the Hartree-Fock approximation but results in a doubling of the bound-state spectrum within the energy gap. The HF bound states may be recovered in the small-U limit as the average of the two separate bound states. For increasing U, the novel pronounced low-energy bound states tend towards the center of the gap while the other bound states approach the gap edge and their spectral weights vanish.

  20. Information Transmission and Anderson Localization in two-dimensional networks of firing-rate neurons

    NASA Astrophysics Data System (ADS)

    Natale, Joseph; Hentschel, George

    Firing-rate networks offer a coarse model of signal propagation in the brain. Here we analyze sparse, 2D planar firing-rate networks with no synapses beyond a certain cutoff distance. Additionally, we impose Dale's Principle to ensure that each neuron makes only or inhibitory outgoing connections. Using spectral methods, we find that the number of neurons participating in excitations of the network becomes insignificant whenever the connectivity cutoff is tuned to a value near or below the average interneuron separation. Further, neural activations exceeding a certain threshold stay confined to a small region of space. This behavior is an instance of Anderson localization, a disorder-induced phase transition by which an information channel is rendered unable to transmit signals. We discuss several potential implications of localization for both local and long-range computation in the brain. This work was supported in part by Grants JSMF/ 220020321 and NSF/IOS/1208126.

  1. Simulation of Anderson localization in a random fiber using a fast Fresnel diffraction algorithm

    NASA Astrophysics Data System (ADS)

    Davis, Jeffrey A.; Cottrell, Don M.

    2016-06-01

    Anderson localization has been previously demonstrated both theoretically and experimentally for transmission of a Gaussian beam through long distances in an optical fiber consisting of a random array of smaller fibers, each having either a higher or lower refractive index. However, the computational times were extremely long. We show how to simulate these results using a fast Fresnel diffraction algorithm. In each iteration of this approach, the light passes through a phase mask, undergoes Fresnel diffraction over a small distance, and then passes through the same phase mask. We also show results where we use a binary amplitude mask at the input that selectively illuminates either the higher or the lower index fibers. Additionally, we examine imaging of various sized objects through these fibers. In all cases, our results are consistent with other computational methods and experimental results, but with a much reduced computational time.

  2. Decay of a nonlinear impurity in a structured continuum from a nonlinear Fano-Anderson model

    SciTech Connect

    Longhi, Stefano

    2007-05-01

    The decay dynamics of a nonlinear impurity mode embedded in a linear structured continuum is theoretically investigated in the framework of a nonlinear Fano-Anderson model. A gradient flow dynamics for the survival probability is derived in the Van Hove ({lambda}{sup 2}t) limit by a multiple-scale asymptotic analysis, and the role of nonlinearity on the decay law is discussed. In particular, it is shown that the existence of bound states embedded in the continuum acts as transient trapping states which slow down the decay. The dynamical behavior predicted in the {lambda}{sup 2}t limit is studied in detail for a simple tight-binding one-dimensional lattice model, which may describe electron or photon transport in condensed matter or photonic systems. Numerical simulations of the underlying equations confirm, in particular, the trapping effect in the decay process due to bound states embedded in the continuum.

  3. The Ce 4{ital f} surface shift: A test for the Anderson-impurity Hamiltonian

    SciTech Connect

    Duo, L.; De Rossi, S.; Vavassori, P.; Ciccacci, F.; Olcese, G.L.; Chiaia, G.; Lindau, I.

    1996-12-01

    Evidence is provided of the role of the different hybridization strengths between the surface and the bulk in determining the magnitude of the surface shift for the shallow Ce 4{ital f} levels, with respect to the deeper core levels. This was achieved by comparing the photoemission core levels for a weakly hybridized case (CeAl) to a case of intermediate hybridization ({gamma}-Ce). For CeAl a 4{ital f} surface shift of 0.45 eV was observed, similar to that for the 5{ital p} core level, whereas a smaller (if any) 4{ital f} surface shift was observed for {gamma}-Ce. Model calculations based on the Anderson impurity Hamiltonian are shown to give a correct evaluation of this effect, which can be exploited as a way of testing the results of such a description for the Ce {ital f} states. {copyright} {ital 1996 The American Physical Society.}

  4. Measuring service quality at the University of Texas M.D. Anderson Cancer Center.

    PubMed

    Anderson, E A; Zwelling, L A

    1996-01-01

    Evaluates the service quality of four clinics at the University of Texas M.D. Anderson Cancer Center using a questionnaire methodology. The SERVQUAL instrument was administered to patients of the Medical Breast, Leukemia, Medical Gastroenterology and Bone Marrow Aspiration clinics. Results show that, according to the service gap methodology of comparing expectations and perceptions, across all four clinics the issues of billing accuracy and waiting times are deemed by patients as significant problems. In comparing the individual clinics, the Medical Gastroenterology and Leukemia clinics are best performers and the Medical Breast clinic is the worst. However, these differences in performance are due to differences in patients' expectations of service quality, rather than differences in perceptions. Concludes that customer expectations can have a strong impact on a firm's evaluation of its service quality.

  5. Perfect absorption in nanotextured thin films via Anderson-localized photon modes

    NASA Astrophysics Data System (ADS)

    Aeschlimann, Martin; Brixner, Tobias; Differt, Dominik; Heinzmann, Ulrich; Hensen, Matthias; Kramer, Christian; Lükermann, Florian; Melchior, Pascal; Pfeiffer, Walter; Piecuch, Martin; Schneider, Christian; Stiebig, Helmut; Strüber, Christian; Thielen, Philip

    2015-10-01

    The enhancement of light absorption in absorber layers is crucial in a number of applications, including photovoltaics and thermoelectrics. The efficient use of natural resources and physical constraints such as limited charge extraction in photovoltaic devices require thin but efficient absorbers. Among the many different strategies used, light diffraction and light localization at randomly nanotextured interfaces have been proposed to improve absorption. Although already exploited in commercial devices, the enhancement mechanism for devices with nanotextured interfaces is still subject to debate. Using coherent two-dimensional nanoscopy and coherent light scattering, we demonstrate the existence of localized photonic states in nanotextured amorphous silicon layers as used in commercial thin-film solar cells. Resonant absorption in these states accounts for the enhanced absorption in the long-wavelength cutoff region. Our observations establish that Anderson localization—that is, strong localization—is a highly efficient resonant absorption enhancement mechanism offering interesting opportunities for the design of efficient future absorber layers.

  6. Localization in the Anderson model with long-range correlated hopping and on-site disorders

    NASA Astrophysics Data System (ADS)

    Lotfallahzadeh, Shiva; Anvari, Mehrnaz; Ekhtiary, Niko; Esmailpour, Ayoub; Rahimi Tabar, M. Reza

    2015-01-01

    We study the metal-insulator transition in one-dimensional Anderson binary alloy with long-range disordered hopping integrals and on-site energies using the transfer matrix method. In this model, the on-site energies and hopping integrals are distributed randomly with long-range correlations characterized by power spectrum of the type ?, with different exponents ? and ?, respectively. We determine the critical value of long-range correlation exponent of hopping integral ? in the presence of only off-diagonal disorder in which the transition from localized to extended states occurs in thermodynamic limit. When both of the on-site energies and hopping integrals are disordered, there are two parameters ? and ? that control the metal-insulator transition in the system. We draw the phase diagram which separates the localized regime from extended one and it shows the critical values of ? for a given value of ?.

  7. GW approach to Anderson model in and out of equilibrium : scaling properties in the Kondo regime.

    SciTech Connect

    Spataru, Dan Catalin

    2010-03-01

    The low-energy properties of the Anderson model for a single impurity coupled to two leads are studied using the GW approximation. We find that quantities such as the spectral function at zero temperature, the linear-response conductance as function of temperature or the differential conductance as function of bias voltage exhibit universal scaling behavior in the Kondo regime. We show how the form of the GW scaling functions relates to the form of the scaling functions obtained from the exact solution at equilibrium. We also compare the energy scale that goes inside the GW scaling functions with the exact Kondo temperature, for a broad range of the Coulomb interaction strength in the asymptotic regime. This analysis allows to clarify a presently suspended question in the literature, namely whether or not the GW solution captures the Kondo resonance.

  8. The Anderson localization problem, the Fermi-Pasta-Ulam paradox and the generalized diffusion approach

    NASA Astrophysics Data System (ADS)

    Kuzovkov, V. N.

    2011-12-01

    The goal of this paper is twofold. First, based on the interpretation of a quantum tight-binding model in terms of a classical Hamiltonian map, we consider the Anderson localization (AL) problem as the Fermi-Pasta-Ulam (FPU) effect in a modified dynamical system containing both stable and unstable (inverted) modes. Delocalized states in the AL are analogous to the stable quasi-periodic motion in FPU, whereas localized states are analogous to thermalization, respectively. The second aim is to use the classical Hamilton map for a simplified derivation of exact equations for the localization operator H(z). The latter was presented earlier (Kuzovkov et al 2002 J. Phys.: Condens. Matter 14 13777) treating the AL as a generalized diffusion in a dynamical system. We demonstrate that counter-intuitive results of our studies of the AL are similar to the FPU counter-intuitivity.

  9. Intrafamilial phenotypic variability in four families with Anderson-Fabry disease.

    PubMed

    Rigoldi, M; Concolino, D; Morrone, A; Pieruzzi, F; Ravaglia, R; Furlan, F; Santus, F; Strisciuglio, P; Torti, G; Parini, R

    2014-09-01

    We analysed the clinical history of 16 hemizygous males affected by Anderson-Fabry Disease, from four families, to verify their intrafamilial phenotypic variability. Seven male patients, ranging from 26 to 61 years of age, died, whereas nine (age range 23-55) are alive. Eleven patients have undergone enzyme replacement therapy (ERT) for a period of 5-10 years. We have found a wide range of intrafamilial phenotypic variability in these families, both in terms of target-organs and severity of the disease. Overall, our findings confirm previous data from the literature showing a high degree of intrafamilial phenotypic variability in patients carrying the same mutation. Furthermore, our results underscore the difficulty in giving accurate prognostic information to patients during genetic counselling, both in terms of rate of disease progression and involvement of different organs, when such prognosis is solely based on the patient's family history.

  10. Local integrals of motion in the two-site Anderson-Hubbard model

    NASA Astrophysics Data System (ADS)

    Wortis, R.; Kennett, Malcolm P.

    2017-10-01

    It has been proposed that the states of fully many-body localized systems can be described in terms of conserved local pseudospins. Due to the multitude of ways to define these, the explicit identification of the optimally local pseudospins in specific systems is non-trivial. Given continuing intense interest in the role of disorder in strongly correlated systems, we consider the disordered Hubbard model. By studying a small system we provide concrete examples of the form of local integrals of motion in the Anderson-Hubbard model. Moreover, we are able not only to identify the most local choice but also to explore the nature of the distribution of possible choices. We track the evolution of the optimally localized pseudospins as hopping and interactions are varied to move the system away from the trivially localized atomic limit.

  11. VizieR Online Data Catalog: Radio observations of Galactic WISE HII regions (Anderson+, 2015)

    NASA Astrophysics Data System (ADS)

    Anderson, L. D.; Armentrout, W. P.; Johnstone, B. M.; Bania, T. M.; Balser, D. S.; Wenger, T. V.; Cunningham, V.

    2016-01-01

    We draw our targets from the MIR objects in the WISE catalog of Anderson+, 2014, J/ApJS/212/1. We also include in our sample Sharpless H II regions (Sharpless 1959, VII/20). See section 2 for further details. Our observations were made with the GBT 100m telescope from 2012 July through 2014 August. There are seven radio recombination lines (RRLs) that can be cleanly observed simultaneously with the GBT in the X-band: H87α to H93α. We average these seven RRLs (each at two orthogonal polarizations) to create a single average RRL spectrum. We followed the same GBT observational procedure as in the original HRDS (Green Bank Telescope H II Region Discovery Survey (GBT HRDS; Bania et al. 2010ApJ...718L.106B). (3 data files).

  12. Financial protection against nuclear hazards: thirty years' experience under the Price-Anderson Act

    SciTech Connect

    Not Available

    1984-01-01

    Supplementing earlier reports on ways to provide financial protection against the potential hazards involved in the production of nuclear energy by analyzing the issues raised in the Silkwood v. Kerr-McGee Corporation decision, the author explores the impact of the case on the availability of funds to compensate the public and any increased exposure of the nuclear industry or the federal government to public liability. She concludes that the decision will have a significant impact on the day-to-day administration of claims, and could lead to higher premiums. The court would have to determine the priority given to claims in the event of a catastrophic accident, in which case the only significant impact would be under amendments to the Price-Anderson Act which resulted in elimination of its coverage or a substantial increase in or elimination of the limitation on liability.

  13. Thermodynamic properties of the periodic Anderson model:  X-boson treatment

    NASA Astrophysics Data System (ADS)

    Franco, R.; Figueira, M. S.; Foglio, M. E.

    2003-11-01

    We study the specific-heat dependence of the periodic Anderson model (PAM) in the limit of U=∞ employing the X-boson treatment in two different regimes of the PAM: the heavy fermion Kondo (HF-K) and the local magnetic moment regime (HF-LMM). We obtain a multiple peak structure for the specific heat in agreement with the experimental results as well as the increase of the electronic effective mass at low temperatures associated with the HF-K regime. The entropy per site at low T tends to zero in the HF-K regime, corresponding to a singlet ground state, and it tends to kBln 2 in the HF-LMM, corresponding to a doublet ground state at each site. The linear coefficient γ(T)=Cv(T)/T of the specific heat qualitatively agrees with the experimental results obtained for different materials in the two regimes considered here.

  14. The effect of the exhaustion on the magnetic and optical properties of the periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Figueira, M. S.; Silva-Valencia, J.; Franco, R.

    We are interested in the study of the "exhaustion problem", as originally introduced by Nozières, in the Kondo regime, and its manifestations on the magnetic and optical properties of the periodic Anderson model (PAM). In the case of the impurity problem there is only one single energy scale governed by the Kondo temperature TK, below which the local moment is screened by the conduction electrons. In the lattice case, there is the emergence of another energy scale governed by the coherence temperature T*, below which the system forms a Fermi liquid. The "exhaustion problem" becomes especially relevant when few conduction electrons nc≪1 are available to screen the local spins. To solve the model we employ the X-boson approach. We computed numerically the evolution of the magnetic susceptibility and the optical conductivity, in the heavy fermion Kondo-exhaustion regime, as a function of the temperature T, when the total occupation number Nt was kept constant.

  15. A Cartesian quasi-classical model to nonequilibrium quantum transport: the Anderson impurity model.

    PubMed

    Li, Bin; Levy, Tal J; Swenson, David W H; Rabani, Eran; Miller, William H

    2013-03-14

    We apply the recently proposed quasi-classical approach for a second quantized many-electron Hamiltonian in Cartesian coordinates [B. Li and W. H. Miller, J. Chem. Phys. 137, 154107 (2012)] to correlated nonequilibrium quantum transport. The approach provides accurate results for the resonant level model for a wide range of temperatures, bias, and gate voltages, correcting the flaws of our recently proposed mapping using action-angle variables. When electron-electron interactions are included, a Gaussian function scheme is required to map the two-electron integrals, leading to quantitative results for the Anderson impurity model. In particular, we show that the current mapping is capable of capturing quantitatively the Coulomb blockade effect and the temperature dependence of the current below and above the blockade.

  16. View of Anderson and Yurchikhin working in the US Lab during Expedition 15

    NASA Image and Video Library

    2007-08-30

    ISS015-E-25420 (30 Aug. 2007) --- Astronaut Clay Anderson (left), Expedition 15 flight engineer, works the controls of the station's robotic arm, Canadarm2; while cosmonaut Fyodor N. Yurchikhin, commander representing Russia's Federal Space Agency, works with docking systems in the Destiny laboratory of the International Space Station during Pressurized Mating Adapter-3 (PMA-3) transfer operations. Using the Canadarm2, the PMA-3 was undocked from the Unity node's left side at 7:18 a.m. (CDT) and docked to Unity's lower port at 8:07 a.m. to prepare for the arrival of Node 2, the Harmony module, on the STS-120 flight of Space Shuttle Discovery in October 2007.

  17. d -wave superconductivity in the frustrated two-dimensional periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Wu, Wei; Tremblay, A.-M.-S.

    2015-01-01

    Superconductivity in heavy-fermion materials can sometimes appear in the incoherent regime and in proximity to an antiferromagnetic quantum critical point. Here, we study these phenomena using large-scale determinant quantum Monte Carlo simulations and the dynamical cluster approximation with various impurity solvers for the periodic Anderson model with frustrated hybridization. We obtain solid evidence for a dx2-y2 superconducting phase arising from an incoherent normal state in the vicinity of an antiferromagnetic quantum critical point. There is a coexistence region, and the width of the superconducting dome increases with frustration. Through a study of the pairing dynamics, we find that the retarded spin fluctuations give the main contribution to the pairing glue. These results are relevant for unconventional superconductivity in the Ce-115 family of heavy fermions.

  18. Doping-induced perturbation and percolation in the two-dimensional Anderson lattice

    PubMed Central

    Wei, Lan-ying; Yang, Yi-feng

    2017-01-01

    We examine the doping effects in the two-dimensional periodic Anderson model using the determinant Quantum Monte Carlo (DQMC) method. We observe bound states around the Kondo hole site and find that the heavy electron states are destroyed at the nearest-neighbor sites. Our results show no clear sign of hybridization oscillation predicted in previous mean-field calculations. We further study the electron transport with increasing doping and as a function of temperature and obtain a critical doping xc ≈ 0.6 that marks a transition from the Kondo insulator regime to the single-ion Kondo regime. The value of xc is in good agreement with the predicted threshold for the site percolation. Our results confirm the percolative nature of the insulator-metal transition widely observed in doped Kondo insulators. PMID:28383021

  19. Numerical results for the Edwards-Anderson spin-glass model at low temperature

    NASA Astrophysics Data System (ADS)

    Fernández, Julio F.; Alonso, Juan J.

    2013-04-01

    We have simulated Edwards-Anderson (EA) as well as Sherrington-Kirkpatrick systems of L3 spins. After averaging over large sets of EA system samples of 3≤L≤10, we obtain accurate numbers for distributions p(q) of the overlap parameter q at very low-temperature T. We find p(0)/T→0.233(4) as T→0. This is in contrast with the droplet scenario of spin glasses. We also study the number of mismatched links—between replica pairs—that come with large scale excitations. Contributions from small scale excitations are discarded. We thus obtain for the fractal dimension of outer surfaces of q˜0 excitations in the EA model ds→2.59(3) as T→0. This is in contrast with ds→3 as T→0 that is predicted by mean-field theory for the macroscopic limit.

  20. Critical behavior at dynamical phase transition in the generalized Bose-Anderson model

    NASA Astrophysics Data System (ADS)

    Chichinadze, Dmitry V.; Rubtsov, Alexey N.

    2017-05-01

    Critical properties of the dynamical phase transition in the quenched generalized Bose-Anderson impurity model are studied in the mean-field limit of an infinite number of channels. The transition separates the evolution toward ground state and toward the branch of stable excited states. We perform numerically exact simulations of a close vicinity of the critical quench amplitude. The relaxation constant describing the asymptotic evolution toward ground state, as well as asymptotic frequency of persistent phase rotation and number of cloud particles at stable excited state are power functions of the detuning from the critical quench amplitude. The critical evolution (separatrix between the two regimes) shows a non-Lyapunov power-law instability arising after a certain critical time. The observed critical behavior is attributed to the irreversibility of the dynamics of particles leaving the cloud and to memory effects related to the low-energy behavior of the lattice density of states.

  1. Severe hypertrophic cardiomyopathy in a patient with atypical Anderson-Fabry disease.

    PubMed

    Masarone, Daniele; Duro, Giovanni; Dellegrottaglie, Santo; Colomba, Paolo; Rubino, Marta; Cirillo, Annapaola; Pisani, Antonio; Caiazza, Martina; Elliott, Perry Mark; Calabrò, Paolo; Pacileo, Giuseppe; Limongelli, Giuseppe

    2017-09-22

    Anderson-Fabry disease (AFD) is a hereditary disorder caused by a deficiency in the lysosomal enzyme α-galactosidase A which causes dysfunctions in multiple organ systems. Cardiac manifestation includes left ventricular hypertrophy, thickening of the valves, conduction disturbances and in the late phase, extensive areas of myocardial fibrosis with increased risk of sudden cardiac death. Case example: A case of AFD with exclusive cardiac involvement is described. During follow-up, due to the high risk of life-threatening arrhythmic events, implantation of an implantable cardioverter defibrillator is performed. AFD patients with advanced cardiac disease might represent a subgroup of patients who may require an implantable cardioverter defibrillator for primary prevention of sudden cardiac death.

  2. Cardiac Anderson-Fabry disease: lessons from a 25-year-follow up.

    PubMed

    Brito, Dulce; Miltenberger-Miltenyi, Gabriel; Moldovan, Oana; Navarro, Carmen; Madeira, Hugo Costa

    2014-04-01

    Sarcomeric hypertrophic cardiomyopathy (HCM) is the most common genetic cause of unexplained left ventricular hypertrophy and has no specific treatment. Anderson-Fabry disease (AFD) is rare and usually multisystemic, but occasionally expresses clinically as a predominantly cardiac phenotype mimicking HCM. We describe an illustrative case of a patient followed regularly for 25 years with a diagnosis of familial HCM and no identified sarcomeric mutations. Next-generation sequencing analysis identified a novel pathogenic mutation in the GLA gene, leading to a diagnosis of previously unknown multisystemic AFD, with consequent implications for the patient's treatment and prognosis and familial screening. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  3. Physical characteristics of the M.D. Anderson Hospital clinical neutron beam.

    PubMed

    Horton, J L; Otte, V A; Schultheiss, T E; Stafford, P M; Sun, T; Zermeno, A

    1988-09-01

    The physical characteristics of the M.D. Anderson Hospital (MDAH) clinical neutron beam are presented. The central-axis percent depth-dose values are intermediate between a 4 and 6 MV X-ray beam. The build-up curves reach a depth of maximum dose at 1.2 cm and have surface dose values of approximately 30%. Teflon flattening filters are employed to flatten the beam at the depth of the 75% dose level. Two wedges are available for shaping the beam; they are made of Teflon and produce wedge angles of 31 degrees and 45 degrees as defined by the ICRU. Output factors ranged from 0.88 for a 4 x 4 cm field to 1.12 for a 20 x 20 cm field. Tungsten blocks reduced the dose received at Dmax to 25% of the unblocked value but only 52% of the unblocked value at a depth of 22.8 cm.

  4. Universal scaling in the Knight-shift anomaly of the doped periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Jiang, M.; Yang, Yi-feng

    2017-06-01

    We report a dynamical cluster approximation investigation of the doped periodic Anderson model to explain the universal scaling in the Knight-shift anomaly predicted by the phenomenological two-fluid model and confirmed in many heavy-fermion compounds. We calculate the quantitative evolution of the orbital-dependent magnetic susceptibility and reproduce correctly the two-fluid prediction in a large range of doping and hybridization. Our results confirm the presence of a temperature/energy scale T* for the universal scaling and show distinctive behaviors of the Knight-shift anomaly in response to other "orders" at low temperatures. However, comparison with the temperature evolution of the calculated resistivity and quasiparticle spectral peak indicates a different characteristic temperature from T*, in contradiction with the experimental observation in CeCoIn5 and other compounds. This reveals a missing piece in the current model calculations in explaining the two-fluid phenomenology.

  5. One-dimensional Anderson Localization: distribution of wavefunction amplitude and phase at the band center

    SciTech Connect

    Kravtsov, V. E.; Yudson, V. I.

    2009-05-14

    The statistics of normalized wavefunctions in the one-dimensional (1d) Anderson model of localization is considered. It is shown that at any energy that corresponds to a rational filling factor f = (p/q) there is a statistical anomaly which is seen in expansion of the generating function (GF) to the order q-2 in the disorder parameter. We study in detail the principle anomaly at f = (1/2) that appears in the leading order. The transfer-matrix equation of the Fokker-Planck type with a two-dimensional internal space is derived for GF. It is shown that the zero-mode variant of this equation is integrable and a solution for the generating function is found in the thermodynamic limit.

  6. Beyond Anderson localization in 1D: anomalous localization of microwaves in random waveguides.

    PubMed

    Fernández-Marín, A A; Méndez-Bermúdez, J A; Carbonell, J; Cervera, F; Sánchez-Dehesa, J; Gopar, V A

    2014-12-05

    Experimental evidence demonstrating that anomalous localization of waves can be induced in a controllable manner is reported. A microwave waveguide with dielectric slabs randomly placed is used to confirm the presence of anomalous localization. If the random spacing between slabs follows a distribution with a power-law tail (Lévy-type distribution), unconventional properties in the microwave-transmission fluctuations take place revealing the presence of anomalous localization. We study both theoretically and experimentally the complete distribution of the transmission through random waveguides characterized by α=1/2 ("Lévy waveguides") and α=3/4, α being the exponent of the power-law tail of the Lévy-type distribution. As we show, the transmission distributions are determined by only two parameters, both of them experimentally accessible. Effects of anomalous localization on the transmission are compared with those from the standard Anderson localization.

  7. Measuring the Edwards-Anderson order parameter of the Bose glass: A quantum gas microscope approach

    NASA Astrophysics Data System (ADS)

    Thomson, S. J.; Walker, L. S.; Harte, T. L.; Bruce, G. D.

    2016-11-01

    With the advent of spatially resolved fluorescence imaging in quantum gas microscopes, it is now possible to directly image glassy phases and probe the local effects of disorder in a highly controllable setup. Here we present numerical calculations using a spatially resolved local mean-field theory, show that it captures the essential physics of the disordered system, and use it to simulate the density distributions seen in single-shot fluorescence microscopy. From these simulated images we extract local properties of the phases which are measurable by a quantum gas microscope and show that unambiguous detection of the Bose glass is possible. In particular, we show that experimental determination of the Edwards-Anderson order parameter is possible in a strongly correlated quantum system using existing experiments. We also suggest modifications to the experiments which will allow further properties of the Bose glass to be measured.

  8. Anderson transition of two-dimensional spinful electrons in the Gaussian unitary ensemble

    NASA Astrophysics Data System (ADS)

    Wang, C.; Wang, X. R.

    2017-09-01

    We study the Anderson localization of disordered two-dimensional electron gases (2DEGs) on a square lattice subject to a perpendicular magnetic field B , random scalar potentials, and Rashba spin-orbit interactions. Our focus is on the weak magnetic field region, motivated by the intriguing question of how those extended states, existing in the absence of the magnetic field (B =0 ) when the 2DEGs are the Gaussian symplectic ensemble, change with B . Using highly accurate numerical procedures based on the transfer matrix technique and the level statistics, we found that a metallic phase exists at weak magnetic fields, in contrast to the predictions of the one-parameter scaling theory that all states are localized at weak fields except at zero field, and the metallic phase evolves continuously into those at strong magnetic fields. A schematic phase diagram drawn in the field-energy plane elucidates the occurrence and evolution of extended states.

  9. Doping-induced perturbation and percolation in the two-dimensional Anderson lattice.

    PubMed

    Wei, Lan-Ying; Yang, Yi-Feng

    2017-04-06

    We examine the doping effects in the two-dimensional periodic Anderson model using the determinant Quantum Monte Carlo (DQMC) method. We observe bound states around the Kondo hole site and find that the heavy electron states are destroyed at the nearest-neighbor sites. Our results show no clear sign of hybridization oscillation predicted in previous mean-field calculations. We further study the electron transport with increasing doping and as a function of temperature and obtain a critical doping xc ≈ 0.6 that marks a transition from the Kondo insulator regime to the single-ion Kondo regime. The value of xc is in good agreement with the predicted threshold for the site percolation. Our results confirm the percolative nature of the insulator-metal transition widely observed in doped Kondo insulators.

  10. Multifractal Wavefunction and Universality in the Critical Regime of the Anderson Transition

    NASA Astrophysics Data System (ADS)

    Muttalib, K. A.; Kravtsov, V. E.

    1997-03-01

    We show that a variation of the matrix model of disordered conductors introduced by Moshe, Neuberger and Shapiro (MNS) [PRL 73, 1497 (1994)] based on the idea of a preferential basis for strongly disordered states has multifractality of wavefunctions near the critical regime. Based on the fact that the two-level correlation function of the MNS model near the critical regime is identical to that of a distinct phenomenological model [Muttalib et al, PRL 71, 471 (1993)] whose predictions for the level spacing distribution as well as the number variance agree very well [C. Canali, PR B53, 3713 (1996)] with numerical results from the microscopic tight binding Anderson model, we conjecture that the multifractality obtained is a universal feature in the critical regime.

  11. Numerical renormalization group for the bosonic single-impurity Anderson model: Dynamics

    NASA Astrophysics Data System (ADS)

    Lee, Hyun-Jung; Byczuk, Krzysztof; Bulla, Ralf

    2010-08-01

    The bosonic single-impurity Anderson model (B-SIAM) is studied to understand the local dynamics of an atomic quantum dot (AQD) coupled to a Bose-Einstein condensation (BEC) state, which can be implemented to probe the entanglement and the decoherence of a macroscopic condensate. Our recent approach of the numerical renormalization-group calculation for the B-SIAM revealed a zero-temperature phase diagram, where a Mott phase with local depletion of normal particles is separated from a BEC phase with enhanced density of the condensate. As an extension of the previous work, we present the calculations of the local dynamical quantities of the B-SIAM which reinforce our understanding of the physics in the Mott and the BEC phases.

  12. Multichannel Numerical Renormalization Group study of the Anderson Hamiltonian with multiple impurities

    NASA Astrophysics Data System (ADS)

    Stokes, James; Konik, Robert

    2014-03-01

    Using the Numerical Renormalization Group (NRG), the low energy sector of the Anderson Hamiltonian with two impurities in parallel has been previously argued to be consistent with an underscreened spin-1 Kondo effect (R. Zitko and J. Bonca, Phys. Rev. B 76, 241305 (2007); Logan et al., Phys. Rev. B 80, 125117 (2009)). Bethe Ansatz and slave boson calculations have given the ground state as a singlet (M. Kulkarni and R. M. Konik, Phys. Rev. B 83, 245121 (2011)). As an attempt to understand these differences, we have developed a modified NRG routine that takes into account the multiple channels arising from the logarithmic discretization of the Fermi sea. This could conceivably allow for more complicated screening processes suggested by the Bethe ansatz computations. Results of studies using this code for various numbers of impurities and channels will be presented and discussed in relationship to these conflicting views.

  13. High-energy neutron dosimetry at the Clinton P. Anderson Meson Physics Facility

    SciTech Connect

    Mallett, M.W.; Vasilik, D.G.; Littlejohn, G.J.; Cortez, J.R.

    1990-01-01

    Neutron energy spectrum measurements performed at the Clinton P. Anderson Meson Physics Facility indicated potential areas for high energy neutron exposure to personnel. The low sensitivity of the Los Alamos thermoluminescent dosimeter (TLD) to high energy neutrons warranted issuing a NTA dosimeter in addition to the TLD badge to employees entering these areas. The dosimeter consists of a plastic holder surrounding NTA film that has been desiccated and sealed in a dry nitrogen environment. A study of the fading of latent images in NTA film demonstrated the success of this packaging method to control the phenomenon. The Los Alamos NTA dosimeter is characterized and the fading study discussed. 10 refs., 4 figs., 2 tabs.

  14. Leveraging Anderson Acceleration for improved convergence of iterative solutions to transport systems

    SciTech Connect

    Willert, Jeffrey; Taitano, William T.; Knoll, Dana

    2014-09-15

    In this note we demonstrate that using Anderson Acceleration (AA) in place of a standard Picard iteration can not only increase the convergence rate but also make the iteration more robust for two transport applications. We also compare the convergence acceleration provided by AA to that provided by moment-based acceleration methods. Additionally, we demonstrate that those two acceleration methods can be used together in a nested fashion. We begin by describing the AA algorithm. At this point, we will describe two application problems, one from neutronics and one from plasma physics, on which we will apply AA. We provide computational results which highlight the benefits of using AA, namely that we can compute solutions using fewer function evaluations, larger time-steps, and achieve a more robust iteration.

  15. Classical mapping for Hubbard operators: Application to the double-Anderson model

    SciTech Connect

    Li, Bin; Miller, William H.; Levy, Tal J.; Rabani, Eran

    2014-05-28

    A classical Cartesian mapping for Hubbard operators is developed to describe the nonequilibrium transport of an open quantum system with many electrons. The mapping of the Hubbard operators representing the many-body Hamiltonian is derived by using analogies from classical mappings of boson creation and annihilation operators vis-à-vis a coherent state representation. The approach provides qualitative results for a double quantum dot array (double Anderson impurity model) coupled to fermionic leads for a range of bias voltages, Coulomb couplings, and hopping terms. While the width and height of the conduction peaks show deviations from the master equation approach considered to be accurate in the limit of weak system-leads couplings and high temperatures, the Hubbard mapping captures all transport channels involving transition between many electron states, some of which are not captured by approximate nonequilibrium Green function closures.

  16. Extended recursion in operator space (EROS), a new impurity solver for the single impurity Anderson model

    SciTech Connect

    Albers, Robert C; Julien, Jean P

    2008-01-01

    We have developed a new efficient and accurate impurity solver for the single impurity Anderson model (SIAM), which is based on a non-perturbative recursion technique in a space of operators and involves expanding the self-energy as a continued fraction. The method has no special occupation number or temperature restrictions; the only approximation is the number of levels of the continued fraction retained in the expansion. We also show how this approach can be used as a new approach to Dynamical Mean Field Theory (DMTF) and illustrate this with the Hubbard model. The three lowest orders of recursion give the Hartree-Fock, Hubbard I, and Hubbard III approximations. A higher level of recursion is able to reproduce the expected 3-peak structure in the spectral function and Fermi liquid behavior.

  17. Transport across an Anderson quantum dot in the intermediate coupling regime

    NASA Astrophysics Data System (ADS)

    Kern, Johannes; Grifoni, Milena

    2013-09-01

    We describe linear and nonlinear transport across a strongly interacting single impurity Anderson model quantum dot with intermediate coupling to the leads, i.e. with tunnel coupling Γ of the order of the thermal energy k B T. The coupling is large enough that sequential tunneling processes (second order in the tunneling Hamiltonian) alone do not suffice to properly describe the transport characteristics. Upon applying a density matrix approach, the current is expressed in terms of rates obtained by considering a very small class of diagrams which dress the sequential tunneling processes by charge fluctuations. We call this the "dressed second order" (DSO) approximation. One advantage of the DSO is that, still in the Coulomb blockade regime, it can describe the crossover from thermally broadened to tunneling broadened conductance peaks. When the temperature is decreased even further ( k B T < Γ), the DSO captures Kondesque behaviours of the Anderson quantum dot qualitatively: we find a zero bias anomaly of the differential conductance versus applied bias, an enhancement of the conductance with decreasing temperature as well as universality of the shape of the conductance as function of the temperature. We can without complications address the case of a spin degenerate level split energetically by a magnetic field. In case spin dependent chemical potentials are assumed and only one of the four chemical potentials is varied, the DSO yields in principle only one resonance. This seems to be in agreement with experiments with pseudo spin [U. Wilhelm, J. Schmid, J. Weis, K.V. Klitzing, Physica E 14, 385 (2002)]. Furthermore, we get qualitative agreement with experimental data showing a cross-over from the Kondo to the empty orbital regime.

  18. Volcanic ash dispersed in the Wyodak-Anderson coal bed, Powder River Basin, Wyoming

    USGS Publications Warehouse

    Triplehorn, D.M.; Stanton, R.W.; Ruppert, L.F.; Crowley, S.S.

    1991-01-01

    Minerals derived from air-fall volcanic ash were found in two zones in the upper Paleocene Wyodak-Anderson coal bed of the Fort Union Formation in the Powder River Basin of Wyoming, and are the first reported evidence of such volcanic material in this thick (> 20 m) coal bed. The volcanic minerals occur in zones that are not visually obvious because they contain little or no clay. These zones were located by geophysical logs of the boreholes and X-ray radiography of the cores. The zones correspond to two of a series of incremental core samples of the coal bed that have anomalous concentrations of Zr, Ba, Nb, Sr, and P2O5. Two suites of minerals were found in both of the high-density zones. A primary suite (not authigenic) consists of silt-sized quartz grains, biotite, and minor zircon. A minor suite consists of authigenic minerals, including calcite, pyrite, kaolinite, quartz, anatase, barite, and an alumino-phosphate (crandallite?). The original volcanic ash is inferred to have consisted of silica glass containing phenocrysts of quartz, biotite, zircon, and possibly, associated feldspars, pyroxenes, and amphiboles. The glass, as well as the less stable minerals, probably dissolved relatively quickly and contributed to the minor authigenic mineral suite or was removed from the peat as a result of the prevailing hydrologic conditions present in a raised peat formation. This type of volcanic ash suggests that suggests that volcanic material could have rained on the peat; this fallout may have also had a fertilizing effect on the peat by providing nutrients essential for plant growth thus contributing to the thick accumulations of the Wyodak-Anderson bed. Notwithstanding, the presence of these minerals provides evidence for the contribution by volcanic sources to the mineral content of coal, but not as tonsteins. ?? 1991.

  19. Fermi-liquid theory for the single-impurity Anderson model

    NASA Astrophysics Data System (ADS)

    Mora, Christophe; Moca, Cǎtǎlin Paşcu; von Delft, Jan; Zaránd, Gergely

    2015-08-01

    We generalize Nozières' Fermi-liquid theory for the low-energy behavior of the Kondo model to that of the single-impurity Anderson model. In addition to the electrons' phase shift at the Fermi energy, the low-energy Fermi-liquid theory is characterized by four Fermi-liquid parameters: the two given by Nozières that enter to first order in the excitation energy, and two additional ones that enter to second order and are needed away from particle-hole symmetry. We express all four parameters in terms of zero-temperature physical observables, namely the local charge and spin susceptibilities and their derivatives with respect to the local level position. We determine these in terms of the bare parameters of the Anderson model using Bethe ansatz and numerical renormalization group (NRG) calculations. Our low-energy Fermi-liquid theory applies throughout the crossover from the strong-coupling Kondo regime via the mixed-valence regime to the empty-orbital regime. From the Fermi-liquid theory, we determine the conductance through a quantum dot symmetrically coupled to two leads in the regime of small magnetic field, low temperature, and small bias voltage, and compute the coefficients of the ˜B2 , ˜T2 , and ˜V2 terms exactly in terms of the Fermi-liquid parameters. The coefficients of T2, V2, and B2 are found to change sign during the Kondo to empty-orbital crossover. The crossover becomes universal in the limit that the local interaction is much larger than the level width. For completeness, we also compute the shot noise and discuss the resulting Fano factor.

  20. Twisting Anderson pseudospins with light: Quench dynamics in terahertz-pumped BCS superconductors

    NASA Astrophysics Data System (ADS)

    Chou, Yang-Zhi; Liao, Yunxiang; Foster, Matthew S.

    2017-03-01

    We study the preparation (pump) and the detection (probe) of far-from-equilibrium BCS superconductor dynamics in THz pump-probe experiments. In a recent experiment [R. Matsunaga, Y. I. Hamada, K. Makise, Y. Uzawa, H. Terai, Z. Wang, and R. Shimano, Phys. Rev. Lett. 111, 057002 (2013), 10.1103/PhysRevLett.111.057002], an intense monocycle THz pulse with center frequency ω ≃Δ was injected into a superconductor with BCS gap Δ ; the subsequent postpump evolution was detected via the optical conductivity. It was argued that nonlinear coupling of the pump to the Anderson pseudospins of the superconductor induces coherent dynamics of the Higgs (amplitude) mode Δ (t ) . We validate this picture in a two-dimensional BCS model with a combination of exact numerics and the Lax reduction method, and we compute the nonequilibrium phase diagram as a function of the pump intensity. The main effect of the pump is to scramble the orientations of Anderson pseudospins along the Fermi surface by twisting them in the x y plane. We show that more intense pump pulses can induce a far-from-equilibrium phase of gapless superconductivity ("phase I"), originally predicted in the context of interaction quenches in ultracold atoms. We show that the THz pump method can reach phase I at much lower energy densities than an interaction quench, and we demonstrate that Lax reduction (tied to the integrability of the BCS Hamiltonian) provides a general quantitative tool for computing coherent BCS dynamics. We also calculate the Mattis-Bardeen optical conductivity for the nonequilibrium states discussed here.

  1. A novel single-side azobenzene-grafted Anderson-type polyoxometalate for recognition-induced chiral migration.

    PubMed

    Zhang, Bin; Yue, Liang; Wang, Yang; Yang, Yang; Wu, Lixin

    2014-09-25

    A three-component supramolecular hybrid system based on host-guest recognition and electrostatic interaction has been developed for a consecutive chiral transfer from an alpha-cyclodextrin to cationic dyes via the bridge of a new azobenzene-grafted Anderson-type polyoxometalate cluster.

  2. 10 CFR 8.2 - Interpretation of Price-Anderson Act, section 170 of the Atomic Energy Act of 1954.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Interpretation of Price-Anderson Act, section 170 of the Atomic Energy Act of 1954. 8.2 Section 8.2 Energy NUCLEAR REGULATORY COMMISSION INTERPRETATIONS § 8.2... in Nuclear Energy 75 (1959). In the testimony before the Joint Committee last year, Professor...

  3. 10 CFR 8.2 - Interpretation of Price-Anderson Act, section 170 of the Atomic Energy Act of 1954.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Interpretation of Price-Anderson Act, section 170 of the Atomic Energy Act of 1954. 8.2 Section 8.2 Energy NUCLEAR REGULATORY COMMISSION INTERPRETATIONS § 8.2... in Nuclear Energy 75 (1959). In the testimony before the Joint Committee last year, Professor...

  4. 10 CFR 8.2 - Interpretation of Price-Anderson Act, section 170 of the Atomic Energy Act of 1954.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Interpretation of Price-Anderson Act, section 170 of the Atomic Energy Act of 1954. 8.2 Section 8.2 Energy NUCLEAR REGULATORY COMMISSION INTERPRETATIONS § 8.2... in Nuclear Energy 75 (1959). In the testimony before the Joint Committee last year, Professor...

  5. Identification and Analysis of Learning Preferences of Mentally Ill Adults in Rehabilitative Psychosocial Therapy at the Anderson Mental Health Center.

    ERIC Educational Resources Information Center

    Newman, Michael K.

    A study identified and analyzed the learning preferences of 17 seriously and chronically mentally ill adults participating in the rehabilitative psychosocial therapy program at the Toxaway Church Site of the Anderson Mental Health Center. Staff perceived as boring and unfocused the traditional treatment approach that relied mainly upon…

  6. Qualitative breakdown of the noncrossing approximation for the symmetric one-channel Anderson impurity model at all temperatures

    NASA Astrophysics Data System (ADS)

    Sposetti, C. N.; Manuel, L. O.; Roura-Bas, P.

    2016-08-01

    The Anderson impurity model is studied by means of the self-consistent hybridization expansions in its noncrossing (NCA) and one-crossing (OCA) approximations. We have found that for the one-channel spin-1 /2 particle-hole symmetric Anderson model, the NCA results are qualitatively wrong for any temperature, even when the approximation gives the exact threshold exponents of the ionic states. Actually, the NCA solution describes an overscreened Kondo effect, because it is the same as for the two-channel infinite-U single-level Anderson model. We explicitly show that the NCA is unable to distinguish between these two very different physical systems, independently of temperature. Using the impurity entropy as an example, we show that the low-temperature values of the NCA entropy for the symmetric case yield the limit Simp(T =0 ) →ln√{2 }, which corresponds to the zero temperature entropy of the overscreened Kondo model. Similar pathologies are predicted for any other thermodynamic property. On the other hand, we have found that the OCA approach lifts the artificial mapping between the models and restores correct properties of the ground state, for instance, a vanishing entropy at low enough temperatures Simp(T =0 ) →0 . Our results indicate that the very well known NCA should be used with caution close to the symmetric point of the Anderson model.

  7. Genomic organization and reproductive regulation of a carrier/storage protein in the Varroa Mite, Varroa destructor (Anderson & Trueman)

    USDA-ARS?s Scientific Manuscript database

    The complete genomic region and corresponding transcript of the most abundant protein in the phoretic varroa mite, Varroa destructor (Anderson & Trueman), were sequenced and found to be homologous with hemelipoglyco-proteins (HeLP/CP) of acarines. The genomic arrangement showed the presence of 14 in...

  8. The Anderson--Baird-Parker direct plating method versus the most probable number procedure for enumerating Escherichia coli in meats.

    PubMed

    Rayman, M K; Aris, B

    1981-01-01

    Comparison of the Anderson--Baird-Parker direct plating method (DP) and the North American most probable number procedure (MPN) for enumerating Escherichia coli in frozen meats revealed that the DP method is more precise and yields higher counts of E. coli than the MPN procedure. Any of three brands of membrane filters tested was suitable for use in the DP method.

  9. A new dataset of Wood Anderson magnitude from the Trieste (Italy) seismic station

    NASA Astrophysics Data System (ADS)

    Sandron, Denis; Gentile, G. Francesco; Gentili, Stefania; Rebez, Alessandro; Santulin, Marco; Slejko, Dario

    2014-05-01

    The standard torsion Wood Anderson (WA) seismograph owes its fame to the fact that historically it has been used for the definition of the magnitude of an earthquake (Richter, 1935). With the progress of the technology, digital broadband (BB) seismographs replaced it. However, for historical consistency and homogeneity with the old seismic catalogues, it is still important continuing to compute the so called Wood Anderson magnitude. In order to evaluate WA magnitude, the synthetic seismograms WA equivalent are simulated convolving the waveforms recorded by a BB instrument with a suitable transfer function. The value of static magnification that should be applied in order to simulate correctly the WA instrument is debated. The original WA instrument in Trieste operated from 1971 to 1992 and the WA magnitude (MAW) estimates were regularly reported in the seismic station bulletins. The calculation of the local magnitude was performed following the Richter's formula (Richter, 1935), using the table of corrections factor unmodified from those calibrated for California and without station correction applied (Finetti, 1972). However, the WA amplitudes were computed as vector sum rather than arithmetic average of the horizontal components, resulting in a systematic overestimation of approximately 0.25, depending on the azimuth. In this work, we have retrieved the E-W and N-S components of the original recordings and re-computed MAW according to the original Richter (1935) formula. In 1992, the WA recording were stopped, due to the long time required for the daily development of the photographic paper, the costs of the photographic paper and the progress of the technology. After a decade of interruption, the WA was recovered and modernized by replacing the recording on photographic paper with an electronic device and it continues presently to record earthquakes. The E-W and N-S components records were memorized, but not published till now. Since 2004, next to the WA (few

  10. Dual nature of localization in guiding systems with randomly corrugated boundaries: Anderson-type versus entropic

    SciTech Connect

    Tarasov, Yu.V. Shostenko, L.D.

    2015-05-15

    coexist in waveguide-like systems with randomly corrugated boundaries, specifically, the entropic localization and the one-dimensional Anderson (disorder-driven) localization. If the particular mode propagates across the rough segment ballistically, the Fabry–Pérot-type oscillations should be observed in the conductance, which are suppressed for the mode transferred in the Anderson-localized regime.

  11. Commensurability effects in one-dimensional Anderson localization: Anomalies in eigenfunction statistics

    SciTech Connect

    Kravtsov, V.E.; Yudson, V.I.

    2011-07-15

    Highlights: > Statistics of normalized eigenfunctions in one-dimensional Anderson localization at E = 0 is studied. > Moments of inverse participation ratio are calculated. > Equation for generating function is derived at E = 0. > An exact solution for generating function at E = 0 is obtained. > Relation of the generating function to the phase distribution function is established. - Abstract: The one-dimensional (1d) Anderson model (AM), i.e. a tight-binding chain with random uncorrelated on-site energies, has statistical anomalies at any rational point f=(2a)/({lambda}{sub E}) , where a is the lattice constant and {lambda}{sub E} is the de Broglie wavelength. We develop a regular approach to anomalous statistics of normalized eigenfunctions {psi}(r) at such commensurability points. The approach is based on an exact integral transfer-matrix equation for a generating function {Phi}{sub r}(u, {phi}) (u and {phi} have a meaning of the squared amplitude and phase of eigenfunctions, r is the position of the observation point). This generating function can be used to compute local statistics of eigenfunctions of 1d AM at any disorder and to address the problem of higher-order anomalies at f=p/q with q > 2. The descender of the generating function P{sub r}({phi}){identical_to}{Phi}{sub r}(u=0,{phi}) is shown to be the distribution function of phase which determines the Lyapunov exponent and the local density of states. In the leading order in the small disorder we derived a second-order partial differential equation for the r-independent ('zero-mode') component {Phi}(u, {phi}) at the E = 0 (f=1/2 ) anomaly. This equation is nonseparable in variables u and {phi}. Yet, we show that due to a hidden symmetry, it is integrable and we construct an exact solution for {Phi}(u, {phi}) explicitly in quadratures. Using this solution we computed moments I{sub m} = N< vertical bar {psi} vertical bar {sup 2m}> (m {>=} 1) for a chain of the length N {yields} {infinity} and found an

  12. Menstrual Cycle

    MedlinePlus

    ... receive Pregnancy email updates Enter email Submit The menstrual cycle Day 1 starts with the first day of ... drop around Day 25 . This signals the next menstrual cycle to begin. The egg will break apart and ...

  13. Anderson localization on the Cayley tree: multifractal statistics of the transmission at criticality and off criticality

    NASA Astrophysics Data System (ADS)

    Monthus, Cécile; Garel, Thomas

    2011-04-01

    In contrast to finite dimensions where disordered systems display multifractal statistics only at criticality, the tree geometry induces multifractal statistics for disordered systems also off criticality. For the Anderson tight-binding localization model defined on a tree of branching ratio K = 2 with N generations, we consider the Miller-Derrida scattering geometry (1994 J. Stat. Phys. 75 357), where an incoming wire is attached to the root of the tree, and where KN outcoming wires are attached to the leaves of the tree. In terms of the KN transmission amplitudes tj, the total Landauer transmission is T ≡ ∑j|tj|2, so that each channel j is characterized by the weight wj = |tj|2/T. We numerically measure the typical multifractal singularity spectrum f(α) of these weights as a function of the disorder strength W and we obtain the following conclusions for its left termination point α+(W). In the delocalized phase W < Wc, α+(W) is strictly positive α+(W) > 0 and is associated with a moment index q+(W) > 1. At criticality, it vanishes α+(Wc) = 0 and is associated with the moment index q+(Wc) = 1. In the localized phase W > Wc, α+(W) = 0 is associated with some moment index q+(W) < 1. We discuss the similarities with the exact results concerning the multifractal properties of the directed polymer on the Cayley tree.

  14. Statistical properties of the Green function in finite size for Anderson localization models with multifractal eigenvectors

    NASA Astrophysics Data System (ADS)

    Monthus, Cécile

    2017-03-01

    For Anderson localization models with multifractal eigenvectors on disordered samples containing N sites, we analyze in a unified framework the consequences for the statistical properties of the Green function. We focus in particular on the imaginary part of the Green function at coinciding points GxxI≤ft(E-\\text{i}η \\right) and study the scaling with the size N of the moments of arbitrary indices q when the broadening follows the scaling η =\\frac{c}{{{N}δ}} . For the standard scaling regime δ =1 , we find in the two limits c\\ll 1 and c\\gg 1 that the moments are governed by the anomalous exponents Δ (q) of individual eigenfunctions, without the assumption of strong correlations between the weights of consecutive eigenstates at the same point. For the non-standard scaling regimes 0<δ <1 , we obtain that the imaginary Green function follows some Fréchet distribution in the typical region, while rare events are important to obtain the scaling of the moments. We describe the application to the case of Gaussian multifractality and to the case of linear multifractality.

  15. Suitability of Palestine salt dome, Anderson Co. , Texas for disposal of high-level radioactive waste

    SciTech Connect

    Patchick, P.F.

    1980-01-01

    The suitability of Palestine salt dome, in Anderson County, Texas, is in serious doubt for a repository to isolate high-level nuclear waste because of abandoned salt brining operations. The random geographic and spatial occurrence of 15 collapse sinks over the dome may prevent safe construction of the necessary surface installations for a repository. The dissolution of salt between the caprock and dome, from at least 15 brine wells up to 500 feet deep, may permit increased rates of salt dissolution long into future geologic time. The subsurface dissolution is occurring at a rate difficult, if not impossible, to assess or to calculate. It cannot be shown that this dissolution rate is insignificant to the integrity of a future repository or to ancillary features. The most recent significant collapse was 36 feet in diameter and took place in 1972. The other collapses ranged from 27 to 105 feet in diameter and from 1.5 to more than 15 feet in depth. ONWI recommends that this dome be removed from consideration as a candidate site.

  16. An inventory of wetlands in the East Fork Poplar Creek floodplain, Anderson and Roane Counties, Tennessee

    SciTech Connect

    1992-12-01

    An inventory of wetlands within the floodplain of East Fork Poplar Creek (EFPC) in Anderson and Roane Counties, Tennessee was conducted during October, 1991 through May, 1992 for the US Department of Energy (DOE) by the US Army Corps of Engineers, Nashville District. About 15 miles of EFPC channel and 500 acres of its floodplain are contaminated with mercury and other contaminants released from the Y-12 Plant on the DOE Oak Ridge Reservation. The wetland inventory will serve as baseline information for DOE`s remedial action planning and National Environmental Policy Act compliance efforts related to the contamination. In order to provide broad wetland determinations beyond which future wetland definitions are unlikely to expand, the 1989 Federal Manual for Identifying And Delineating Jurisdictional Wetlands was utilized. Using the manual`s methodology in a contaminated system under the approved health and safety plan presented some unique problems, resulting in intrusive sampling for field indicators of hydric soils being accomplished separately from observation of other criteria. Beginning with wetland areas identified on National Wetland Inventory Maps, the entire floodplain was examined for presence of wetland criteria, and 17 wetlands were identified ranging from 0.01 to 2.81 acres in size. The majority of wetlands identified were sized under 1 acre. Some of the wetlands identified were not delineated on the National Wetland Inventory Maps, and much of the wetland area delineated on the maps did not meet the criteria under the 1989 manual.

  17. Nonequilibrium transport in the Anderson-Holstein model with interfacial screening

    NASA Astrophysics Data System (ADS)

    Perfetto, Enrico; Stefanucci, Gianluca

    Image charge effects in nanoscale junctions with strong electron-phonon coupling open the way to unexplored physical scenarios. Here we present a comprehensive study of the transport properties of the Anderson-Holstein model in the presence of dot-lead repulsion. We propose an accurate many-body approach to deal with the simultaneous occurrence of the Franck-Condon blockade and the screening-induced enhancement of the polaron mobility. Remarkably, we find that a novel mechanism of negative differential conductance origins from the competition between the charge blocking due to the electron-phonon interaction and the charge deblocking due to the image charges. An experimental setup to observe this phenomenon is discussed. References [1]E. Perfetto, G. Stefanucci and M. Cini, Phys. Rev. B 85, 165437 (2012). [2] E. Perfetto and G. Stefanucci, Phys. Rev. B 88, 245437 (2013). [3] E. Perfetto and G. Stefanucci, Journal of Computational Electronics 14, 352 (2015). E.P. and G.S. acknowledge funding by MIUR FIRB Grant No. RBFR12SW0J.

  18. Identification of Mott insulators and Anderson insulators in self-assembled gold nanoparticles thin films.

    PubMed

    Jiang, Cheng-Wei; Ni, I-Chih; Tzeng, Shien-Der; Wu, Cen-Shawn; Kuo, Watson

    2014-06-07

    How the interparticle tunnelling affects the charge conduction of self-assembled gold nanoparticles is studied by three means: tuning the tunnel barrier width by different molecule modification and by substrate bending, and tuning the barrier height by high-dose electron beam exposure. All approaches indicate that the metal-Mott insulator transition is governed predominantly by the interparticle coupling strength, which can be quantified by the room temperature sheet resistance. The Hubbard gap, following the prediction of quantum fluctuation theory, reduces to zero rapidly as the sheet resistance decreases to the quantum resistance. At very low temperature, the fate of devices near the Mott transition depends on the strength of disorder. The charge conduction is from nearest-neighbour hopping to co-tunnelling between nanoparticles in Mott insulators whereas it is from variable-range hopping through charge puddles in Anderson insulators. When the two-dimensional nanoparticle network is under a unidirectional strain, the interparticle coupling becomes anisotropic so the average sheet resistance is required to describe the charge conduction.

  19. Renormalization of the periodic Anderson model: An alternative analytical approach to heavy-fermion behavior

    NASA Astrophysics Data System (ADS)

    Hübsch, A.; Becker, K. W.

    2005-04-01

    In this paper a recently developed projector-based renormalization method (PRM) for many-particle Hamiltonians is applied to the periodic Anderson model with the aim to describe heavy-fermion behavior. In this method high-energetic excitation operators instead of high energetic states are eliminated. We arrive at an effective Hamiltonian for a quasifree system which consists of two noninteracting heavy-quasiparticle bands. The resulting renormalization equations for the parameters of the Hamiltonian are valid for large as well as small degeneracy νf of the angular momentum. An expansion in 1/νf is avoided. Within an additional approximation which adapts the idea of a fixed renormalized f level ɛ˜f , we obtain coupled equations for ɛ˜f and the averaged f occupation ⟨nf⟩ . These equations resemble to a certain extent those of the usual slave boson mean-field (SB) treatment. In particular, for large νf the results for the PRM and the SB approach agree perfectly whereas considerable differences are found for small νf .

  20. Analgesic, Anti-Inflammatory, and Antioxidant Activities of Byrsonima duckeana W. R. Anderson (Malpighiaceae)

    PubMed Central

    Verdam, Maria Christina dos Santos; de Andrade, Kleyton Cardoso; Fernandes, Karina Lorena Meira; Machado, Tallita Marques; de Souza, Mayane Pereira; Koolen, Hector Henrique Ferreira; Miyazaki, Cristina Mayumi Sasaki; Kalegari, Milena; Miguel, Marilis Dallarmi; Stuelp-Campelo, Patricia Maria; Miguel, Obdulio Gomes

    2017-01-01

    Background. Byrsonima is a promising neotropical genus, rich in flavonoids and triterpenes, with several proven pharmacological properties. Nevertheless, Byrsonima duckeana W. R. Anderson is an Amazonian species almost not studied. Objective. To assess the antioxidant, anti-inflammatory, and analgesic activities of Byrsonima duckeana leaves. Materials and Methods. We analyzed an ethanol extract and its fractions for polyphenol content and UHPLC-MS/MS, phosphomolybdenum, DPPH, TBARS antioxidant tests, formalin-induced pain, carrageenan-induced peritonitis, acetic acid-induced abdominal writhings, and hot plate assays. Results. All the samples showed high polyphenol content and antioxidant capacity in the phosphomolybdenum, DPPH, and TBARS tests. We identified ethyl gallate, quinic acid, gallic acid, catechin, epicatechin, quercetrin, and quercetin in the samples. B. duckeana was able to reduce leukocyte migration in the carrageenan-induced peritonitis by 43% and the licking time in the formalin test by 57%. In the acetic acid-induced writhing test, the chloroform (FCL) and ethyl acetate (FEA) fractions were the most active samples. FEA was selected for the hot plate test, where all the dosages tested (5, 50, and 200 mg·kg−1) showed significant analgesic activity. Conclusion. B. duckeana has interesting analgesic and antioxidant activities, due to its high phenolic content, especially phenolic acids. PMID:28367492

  1. Quantum Monte Carlo investigation of Knight shift anomaly in Periodic Anderson model

    NASA Astrophysics Data System (ADS)

    Jiang, Mi; Curro, Nicholas; Scalettar, Richard; UC Davis Team; UC Davis Team

    2014-03-01

    We report a Determinant Quantum Monte Carlo investigation of the Knight shift anomaly observed in nuclear magnetic resonance (NMR) of heavy fermion materials. As opposed to normal Fermi liquids, the Knight shift in heavy fermion materials deviates from the total susceptibility χ below a crossover temperature T*. This deviation is believed to originate in the different temperature dependence of the conduction electron and local moment components of the total susceptibility χ. Here we quantify the behavior of χcc(T) ,χcf(T) , and χff(T) in the framework of periodic Anderson model (PAM), focussing on the evolution with different degree of conduction electron-local moment hybridization. These results confirm several predictions of the two-fluid theory of the Knight shift anomaly, including the demonstration of a universal logarithmic divergence of the contribution of the heavy electrons to the Knight shift. This universal behavior, which occurs with decreasing temperature below T* in the paramagnetic state, agrees well with experimental findings, and indicates that different heavy fermion materials exhibit a common scaling, differing only in the coherence temperature scale, T*.

  2. Phase boundaries of power-law Anderson and Kondo models: A poor man's scaling study

    NASA Astrophysics Data System (ADS)

    Cheng, Mengxing; Chowdhury, Tathagata; Mohammed, Aaron; Ingersent, Kevin

    2017-07-01

    We use the poor man's scaling approach to study the phase boundaries of a pair of quantum impurity models featuring a power-law density of states ρ (ɛ ) ∝|ɛ| r , either vanishing (for r >0 ) or diverging (for r <0 ) at the Fermi energy ɛ =0 , that gives rise to quantum phase transitions between local-moment and Kondo-screened phases. For the Anderson model with a pseudogap (i.e., r >0 ), we find the phase boundary for (a) 0 1 , where the phases are separated by first-order quantum phase transitions that are accessible only for broken p-h symmetry. For the p-h-symmetric Kondo model with easy-axis or easy-plane anisotropy of the impurity-band spin exchange, the phase boundary and scaling trajectories are obtained for both r >0 and r <0 . Throughout the regime of weak-to-moderate impurity-band coupling in which poor man's scaling is expected to be valid, the approach predicts phase boundaries in excellent qualitative and good quantitative agreement with the nonperturbative numerical renormalization group, while also establishing the functional relations between model parameters along these boundaries.

  3. The invariant measure for Anderson localized negative index metamaterials continuously disordered

    NASA Astrophysics Data System (ADS)

    Kissel, Glen J.; Williams, Aaron

    We consider one-dimensional photonic bandgap structures with negative index of refraction materials modeled in every layer, or in every other layer. When the index of refraction is randomized, and the number of layers becomes large, the light waves undergo Anderson localization, resulting in confinement of the transmitted energy. Such a photonic bandgap structure can be modeled by a long product of random transfer matrices, from which the (upper) Lyapunov exponent can be calculated to characterize the localization effect. Furstenberg's theorem gives a precise formula to calculate the Lyapunov exponent when the random matrices, under general conditions, are independent and identically distributed. Specifically, Furstenberg's integral formula can be used to calculate the Lyapunov exponent via integration with respect to the probability measure of the random matrices, and with respect to the so-called invariant probability measure of the direction of the vector propagated by the long chain of random matrices. It is this latter invariant probability measure, so fundamental to Furstenberg's theorem, which is generally impossible to determine analytically. Here we use a bin counting technique with Monte Carlo chosen random parameters from a continuous distribution to numerically estimate the invariant measure and then calculate Lyapunov exponents from Furstenberg's integral formula. This result, one of the first times an invariant measure has been calculated for a continuously disordered structure made of alternating layers of positive and negative index materials, is compared to results for all negative index or equivalently all positive index structures.

  4. Magnetic flux creep in HTSC and Anderson-Kim theory (Review Article)

    NASA Astrophysics Data System (ADS)

    Lykov, A. N.

    2014-09-01

    Theoretical results and experimental data on flux creep in high-temperature superconductors (HTSC) are analyzed in this review paper. When reviewing experimental work, the main attention is paid to the most striking experimental results which have had a major impact on the study of flux creep in HTSC. On the other hand, the analysis of theoretical results is focused on the studies which explain the features of flux creep by introducing modifications to the Anderson-Kim (AK) theory, i.e., on the studies that have not received sufficient attention earlier. However, it turned out that the modified AK theory could explain a number of features of flux creep in HTSC: the scaling behavior of current-voltage curves in HTSC, the finite rate of flux creep at ultralow temperatures, the logarithmic dependence of the effective pinning potential on the transport current and its decrease with temperature. The harmonic potential field which is used in this approach makes it possible to solve accurately both the problem of viscous vortex motion and the problem of thermally activated flux creep in this magnetic field. Moreover, the energy distribution of pinning potential and the interaction of vortices with each other are also taken into account in the approach. Thus, the modification of the AK theory consists, essentially, in its refinement and achieving a more realistic approximation.

  5. Basic Properties of Conductivity and Normal Hall Effect in the Periodic Anderson Model

    NASA Astrophysics Data System (ADS)

    Watanabe, Shinji; Miyake, Kazumasa

    2016-04-01

    Exact formulas of diagonal conductivity σxx and Hall conductivity σxy are derived from the Kubo formula in hybridized two-orbital systems with arbitrary band dispersions. On the basis of the theoretical framework for the Fermi liquid based on these formulas, the ground-state properties of the periodic Anderson model with electron correlation and weak impurity scattering are studied on the square lattice. It is shown that imbalance of the mass-renormalization factors causes remarkable increase in σxx and σxy in the valence-fluctuation regime as the f level increases while the cancellation of the renormalization factors causes slight increase in σxx and σxy in the Kondo regime. The Hall coefficient RH shows almost constant behavior in both the regimes. Near half filling, RH is expressed by the total hole density as R{H} = 1/(bar{n}{hole}e) while RH approaches zero near quarter filling, which reflects the curvature of the Fermi surface. These results hold as far as the damping rate for f electrons is less than about 10% of the renormalized hybridization gap. From these results we discuss pressure dependence of residual resistivity and normal Hall effect in Ce- and Yb-based heavy electron systems.

  6. Anderson lattice in the intermediate valence compound Ce3Ni2B2N3-δ

    NASA Astrophysics Data System (ADS)

    Ali, Tahir; Bauer, Ernst; Hilscher, Gerfried; Michor, Herwig

    2011-03-01

    We have studied magnetic, thermodynamic, and transport properties of Ce3Ni2B2N3-δ and its solid solution with the Tc≃13 K superconductor La3Ni2B2N3-δ. The solid solution (La,Ce)3Ni2B2N3-δ reveals a rapid reduction of Tc by increasing the Ce content with a complete suppression of superconductivity at the composition La2.85Ce0.15Ni2B2N3-δ. The low-temperature properties characterize Ce3Ni2B2N3-δ as an intermediate valence system with a moderately enhanced Sommerfeld value γ≃54 mJ/mol K2 and a susceptibility χ0≃1.6×10-3 emu/mol, increased by about one order of magnitude as compared to the respective value χ0≃0.2×10-3 emu/mol of superconducting La3Ni2B2N3-δ (γ=26 mJ/mol K2) which serves as reference with a nonmagnetic rare earth ion. The electrical resistivity and thermoelectric power of Ce3Ni2B2N3-δ are analyzed in terms of the degenerate Anderson lattice model revealing a characteristic Kondo temperature TKALM~1100 K.

  7. Landau theory of Anderson localization and STM spectra in Ga1-x Mnx As

    NASA Astrophysics Data System (ADS)

    Mahmoudian, S.; Dobrosavljevic, V.; Miranda, E.

    2014-03-01

    The recently developed Typical Medium Theory provides the conceptually simplest order parameter description of Anderson localization by self-consistently calculating the geometrically-averaged (typical) local density of states (LDOS). Here we show how spatial correlations can also be captured within such a self-consistent theory, by utilizing the standard Landau method of allowing for (slow) spatial fluctuations of the order parameter, and performing an appropriate gradient expansion. Our theoretical results provide insight into recent STM experiments, which were used to visualize the spatially-fluctuating electronic wave functions near the metal insulator transition in Ga1 - xMnx As . We show that, within our theory, all features of the experiment can be accounted for by considering a model of disorder renormalized by long-range Coulomb interactions. This includes the pseudogap formation, the C (R) ~ 1 / R form of the LDOS autocorrelations function, and the ξ ~ 1 / E energy dependence of the correlation length at criticality. V. Dobrosavljević, Int. J. Mod. Phys. B 24, 1680 (2010).

  8. Non-equilibrium STLS approach to transport properties of single impurity Anderson model

    NASA Astrophysics Data System (ADS)

    Rezai, Raheleh; Ebrahimi, Farshad

    2014-04-01

    In this work, using the non-equilibrium Keldysh formalism, we study the effects of the electron-electron interaction and the electron-spin correlation on the non-equilibrium Kondo effect and the transport properties of the symmetric single impurity Anderson model (SIAM) at zero temperature by generalizing the self-consistent method of Singwi, Tosi, Land, and Sjolander (STLS) for a single-band tight-binding model with Hubbard type interaction to out of equilibrium steady-states. We at first determine in a self-consistent manner the non-equilibrium spin correlation function, the effective Hubbard interaction, and the double-occupancy at the impurity site. Then, using the non-equilibrium STLS spin polarization function in the non-equilibrium formalism of the iterative perturbation theory (IPT) of Yosida and Yamada, and Horvatic and Zlatic, we compute the spectral density, the current-voltage characteristics and the differential conductance as functions of the applied bias and the strength of on-site Hubbard interaction. We compare our spectral densities at zero bias with the results of numerical renormalization group (NRG) and depict the effects of the electron-electron interaction and electron-spin correlation at the impurity site on the aforementioned properties by comparing our numerical result with the order U2 IPT. Finally, we show that the obtained numerical results on the differential conductance have a quadratic universal scaling behavior and the resulting Kondo temperature shows an exponential behavior.

  9. Simulating heavy fermion physics in optical lattice: Periodic Anderson model with harmonic trapping potential

    NASA Astrophysics Data System (ADS)

    Zhong, Yin; Liu, Yu; Luo, Hong-Gang

    2017-10-01

    The periodic Anderson model (PAM), where local electron orbitals interplay with itinerant electronic carriers, plays an essential role in our understanding of heavy fermion materials. Motivated by recent proposals for simulating the Kondo lattice model (KLM) in terms of alkaline-earth metal atoms, we take another step toward the simulation of PAM, which includes the crucial charge/valence fluctuation of local f-electrons beyond purely low-energy spin fluctuation in the KLM. To realize PAM, a transition induced by a suitable laser between the electronic excited and ground state of alkaline-earth metal atoms (1 S 0⇌3 P 0) is introduced. This leads to effective hybridization between local electrons and conduction electrons in PAM. Generally, the SU( N) version of PAM can be realized by our proposal, which gives a unique opportunity to detect large- N physics without complexity in realistic materials. In the present work, high-temperature physical features of standard [ SU(2)] PAM with harmonic trapping potential are analyzed by quantum Monte Carlo and dynamic mean-field theory, where the Mott/orbital-selective Mott state was found to coexist with metallic states. Indications for near-future experiments are provided. We expect our theoretical proposal and (hopefully) forthcoming experiments will deepen our understanding of heavy fermion systems. At the same time, we hope these will trigger further studies on related Mott physics, quantum criticality, and non-trivial topology in both the inhomogeneous and nonequilibrium realms.

  10. Effects of correlated hybridization in the single-impurity Anderson model

    NASA Astrophysics Data System (ADS)

    Líbero, Valter; Veiga, Rodrigo

    2013-03-01

    The development of new materials often dependents on the theoretical foundations which study the microscopic matter, i.e., the way atoms interact and create distinct configurations. Among the interesting materials, those with partially filled d or f orbitals immersed in nonmagnetic metals have been described by the Anderson model, which takes into account Coulomb correlation (U) when a local level (energy Ed) is doubled occupied, and an electronic hybridization between local levels and conduction band states. In addition, here we include a correlated hybridization term, which depends on the local-level occupation number involved. This term breaks particle-hole symmetry (even when U + 2Ed = 0), enhances charge fluctuations on local levels and as a consequence strongly modifies the crossover between the Hamiltonian fixed-points, even suppressing one or other. We exemplify these behaviors showing data obtained from the Numerical Renormalization Group (NRG) computation for the impurity temperature-dependent specific heat, entropy and magnetic susceptibility. The interleaving procedure is used to recover the continuum spectrum after the NRG-logarithmic discretization of the conduction band. Fundação de Amparo à Pesquisa do Estado de São Paulo - FAPESP.

  11. The three-dimensional Edwards-Anderson spin glass in an external magnetic field

    NASA Astrophysics Data System (ADS)

    Yllanes, David; Janus Collaboration

    2014-03-01

    Spin glasses are a longstanding model for the sluggish dynamics that appears at the glass transition. However, in order for spin glasses to be a faithful model for general glassy physics, we need to introduce an external magnetic field to eliminate their time-reversal symmetry. Unfortunately, little is known about the critical behavior of a spin glass in a field in three spatial dimensions. We have carried out a dynamical study combining equilibrium and non-equilibrium data. In particular, using the Janus computer, we have been able to simulate one thousand samples, each with half a million spins, along a time window spanning ten orders of magnitude for several magnetic fields and temperature protocols. Our main conclusion is that the system has a clearly identifiable dynamical transition, which we discuss in terms of different possibilities for the underlying physics (from a thermodynamical spin-glass transition to a mode-coupling crossover). In fact, we are able to make quantitative connections between the Edwards-Anderson spin glass and the physics of supercooled liquids. We also discuss ongoing work in equilibrium from parallel tempering simulations. Supported by the ERC, grant agreement no. 247328.

  12. Agalsidase alfa (Replagal) in the treatment of Anderson-Fabry disease.

    PubMed

    Pastores, Gregory M

    2007-09-01

    Anderson-Fabry disease (AFD) is an X-linked storage disorder caused by a deficiency of the lysosomal hydrolase a-galactosidase A (AGAL) and the resultant accumulation of its glycosphingolipid substrate (Gb3) in several tissue types. Major morbidity and reduced life expectancy among affected individuals are a consequence of renal, cardiac and cerebrovascular involvement. Symptomatic males and females with AFD have been described, although the onset of clinical manifestations may be delayed and more variable among the latter patient group, partly attributed to lyonization. Agalsidase alfa (Replagal()) is a recombinant formulation of human AGAL which has been demonstrated to modify the course of AFD in treated patients. Factors that may influence clinical outcomes include disease stage at the point of treatment initiation and antibody formation. There is incomplete understanding of AFD pathophysiology. Early diagnosis and timely intervention may be essential. The use of adjunctive therapies, directed at risk reduction (eg, aspirin for stroke prophylaxis), require careful scrutiny, but such agents are likely to be vital components of a comprehensive approach to patient care. Long-term studies may clarify the optimal dose and frequency of enzyme administration. Meanwhile, budding strategies such as chaperone-mediated enzyme enhancement may offer the potential for an alternative or multimodality approach to the management of AFD.

  13. Thermodynamic potential of the periodic Anderson model with the X-boson method: chain approximation

    NASA Astrophysics Data System (ADS)

    Franco, R.; Figueira, M. S.; Foglio, M. E.

    2002-05-01

    The periodic Anderson model (PAM) in the U→∞ limit has been studied in a previous work employing the cumulant expansion with the hybridization as perturbation (Figueira et al., Phys. Rev. B 50 (1994) 17 933). When the total number of electrons Nt is calculated as a function of the chemical potential μ in the “chain approximation” (CHA), there are three values of the chemical potential μ for each Nt in a small interval of Nt at low T (Physica A 208 (1994) 279). We have recently introduced the “X-boson” method, inspired in the slave boson technique of Coleman, that solves the problem of nonconservation of probability (completeness) in the CHA as well as removing the spurious phase transitions that appear with the slave boson method in the mean field approximation. In the present paper, we show that the X-boson method solves also the problem of the multiple roots of Nt( μ) that appear in the CHA.

  14. Magnetic moments of chromium-doped gold clusters: the Anderson impurity model in finite systems.

    PubMed

    Hirsch, K; Zamudio-Bayer, V; Langenberg, A; Niemeyer, M; Langbehn, B; Möller, T; Terasaki, A; Issendorff, B V; Lau, J T

    2015-02-27

    The magnetic moment of a single impurity atom in a finite free electron gas is studied in a combined x-ray magnetic circular dichroism spectroscopy, charge transfer multiplet calculation, and density functional theory study of size-selected free chromium-doped gold clusters. The observed size dependence of the local magnetic moment can be understood as a transition from a local moment to a mixed valence regime. This shows that the Anderson impurity model essentially describes finite systems even though the discrete density of states introduces a significant deviation from a bulk metal, and the free electron gas is only formed by less than 10 electrons. Electronic shell closure in the gold host minimizes the interaction of localized impurity states with the confined free electron gas and preserves the magnetic moment of 5 μ_{B} fully in CrAu_{2}^{+} and almost fully in CrAu_{6}^{+}. Even for open-shell species, large local moments are observed that scale with the energy gap of the gold cluster. This indicates that an energy gap in the free electron gas stabilizes the local magnetic moment of the impurity atom.

  15. Magnetic order and Kondo effect in the Anderson-lattice model

    NASA Astrophysics Data System (ADS)

    Bernhard, B. H.; Aguiar, C.; Kogoutiouk, I.; Coqblin, B.

    The Anderson-lattice model has been extensively developed to account for the properties of many anomalous rare-earth compounds and in particular for the competition between the Kondo effect and an antiferromagnetic (AF) phase in a cubic lattice. Here we apply the higher-order decoupling of the equations of motion for the Green Functions (GF) introduced in [H.G. Luo, S.J. Wang, Phys. Rev. B 62 (2000) 1485]. We obtain an improved description of the phase diagram, where the AF phase subsists in a smaller range of the model parameters. As higher-order GF are included in the chain of equations, we are able to calculate directly the local spin-flip correlation function . As a further improvement to the previous approximation of [B.H. Bernhard, C. Aguiar, B. Coqblin, Physica B 378-380 (2006) 712], we obtain a reduced range of existence for the AF phase for the symmetric half-filled case and then we discuss the competition between the AF order and the Kondo effect as a function of the band filling.

  16. Response to the commentaries of Melissa S Anderson and Murray J Dyck.

    PubMed

    Kovacs, Jozsef

    2013-08-01

    Anderson and Dyck claim that the current trend of almost exclusively using citation-based evaluative metrics to assess the research output of scholars is unsound. I agree with them in this, but I feel that, for practical reasons, this system will not disappear in the near future, so we must concentrate on making it fairer. Both commentators doubt whether numerically expressing each contributor's relative contribution is feasible. I admit that an important precondition for this task is the possibility of an informed, democratic debate among equals about the relative contribution of each contributor to the article. Mechanisms should be established to protect vulnerable researchers in the academic field in the same way as safeguards exist today to protect vulnerable research participants. Theoretically, however, I think that the fair allocation of authorship credit is possible, and much of this task is already being performed routinely when contributors determine the order of their names in the byline, being well aware of the widespread assumption that this order mostly mirrors the order of their relative contributions. All they would have to do as an additional task is to express this order in numbers. If they cannot reach a consensus, they could always choose not to express their relative contribution in numbers, in which case the presumption would be that they contributed equally. My proposal could, at best, make the system fairer and, at worst, not reduce the options that evaluators already have.

  17. Finite-size corrections for ground states of Edwards-Anderson spin glasses

    NASA Astrophysics Data System (ADS)

    Boettcher, Stefan; Falkner, Stefan

    2012-05-01

    Extensive computations of ground-state energies of the Edwards-Anderson spin glass on bond-diluted, hypercubic lattices are conducted in dimensions d=3, ..., 7. Results are presented for bond densities exactly at the percolation threshold, p=pc, and deep within the glassy regime, p>pc, where finding ground states is one of the hardest combinatorial optimization problems. Finite-size corrections of the form 1/Nω are shown to be consistent throughout with the prediction ω=1-y/d, where y refers to the "stiffness" exponent that controls the formation of domain wall excitations at low temperatures. At p=pc, an extrapolation for d→∞ appears to match our mean-field results for these corrections. In the glassy phase, however, ω does not approach its anticipated mean-field value of 2/3, obtained from simulations of the Sherrington-Kirkpatrick spin glass on an N-clique graph. Instead, the value of ω reached at the upper critical dimension matches another type of mean-field spin glass models, namely those on sparse random networks of regular degree called Bethe lattices.

  18. Numerical evidence against both mean field and droplet scenarios of the Edwards-Anderson model

    NASA Astrophysics Data System (ADS)

    Fernandez, Julio F.; Alonso, Juan J.

    2013-03-01

    From tempered Monte Carlo simulations, we have obtained accurate probability distributions p (q) of the spin-overlap parameter q for finite Edwards-Anderson (EA) and Sherrington-Kirkpatrick (SK) spin-glass systems at low temperatures. Our results for p (q) follow from averages over 105 disordered samples of linear sizes L = 4 - 8 and over 15 000 samples for L = 10 . In both the SK and EA models, at temperatures as low as 0 . 2Tsg , where Tsg is the transition temperature, p (q) varies insignificantly with L. This does not fit the trend that the droplet model predicts for large L. We have also calculated correlation functions, F (q1 ,q2) , from which rms deviations, δp , over different realizations of quenched disorder, as well as thermal fluctuations, w, of q values, follow. Our numerical results for δp and w scale as √{ L} and 1 / L , respectively, in the SK model. This fits in well with mean field predictions. On the other hand, our data for w and δp vary little, if at all, for the EA model.

  19. Dental findings and rehabilitation in familial osteodysplasia (Anderson type): a case report.

    PubMed

    Deger, S; Tabar, G; Sermet, B; Tanyeri, H; Kurklu, E

    2006-03-01

    Familial osteodysplasia is a disorder of osteogenesis with an autosomal recessive pattern of inheritance which predominantly affects facial bones. No recent case had been reported, particularly from a dental point of view since the syndrome was first described by Anderson et al (JAMA 1972;220:1687-93). A 23-year-old male with familial osteodysplasia was presented in maxillofacial and dental aspects with clinical and radiological manifestations including malocclusion, abnormal teeth alignment, impacted teeth, shape disturbances including uncompleted coronal formation, root shortening with bulbous form, high angled mandible and elongation of the corpus of mandible. Recognition of the syndromal features prior to any dental intervention is of paramount importance because of increased inclination to spontaneous mandibular fractures. Hence, no surgical intervention was performed for impacted teeth. Following the extractions of severely mobile teeth, a definitive restoration was fabricated as distal-extension removable partial dentures with conus crown telescopic system. The aesthetic and functional outcome was satisfactory for the patient. In conclusion, dentists appear to play an important role in the recognition of familial osteodysplasia, based on maxillofacial and dentoalveolar findings. Awareness of the syndromal features, especially of spontaneous fractures, would detect the limitations for dental interventions and treatment planning.

  20. Application of the S=1 underscreened Anderson lattice model to Kondo uranium and neptunium compounds

    NASA Astrophysics Data System (ADS)

    Thomas, Christopher; da Rosa Simões, Acirete S.; Iglesias, J. R.; Lacroix, C.; Perkins, N. B.; Coqblin, B.

    2011-01-01

    Magnetic properties of uranium and neptunium compounds showing the coexistence of the Kondo screening effect and ferromagnetic order are investigated within the Anderson lattice Hamiltonian with a two-fold degenerate f level in each site, corresponding to 5f2 electronic configuration with S=1 spins. A derivation of the Schrieffer-Wolff transformation is presented and the resulting Hamiltonian has an effective f-band term, in addition to the regular exchange Kondo interaction between the S=1 f spins and the s=1/2 spins of the conduction electrons. The resulting effective Kondo lattice model can describe both the Kondo regime and a weak delocalization of the 5f electrons. Within this model we compute the Kondo and Curie temperatures as a function of model parameters, namely the Kondo exchange interaction constant JK, the magnetic intersite exchange interaction JH, and the effective f bandwidth. We deduce, therefore, a phase diagram of the model which yields the coexistence of the Kondo effect and ferromagnetic ordering and also accounts for the pressure dependence of the Curie temperature of uranium compounds such as UTe.

  1. Anderson Localization for Schrödinger Operators on with Strongly Mixing Potentials

    NASA Astrophysics Data System (ADS)

    Bourgain, Jean; Schlag, Wilhelm

    In this paper we show that for a.e. x∈[ 0,2 π) the operators defined on as and with Dirichlet condition ψ- 1= 0, have pure point spectrum in with exponentially decaying eigenfunctions where δ > 0 and are small. As it is a simple consequence of known techniques that for small λ one has [- 2 +δ, 2-δ]⊂ spectrum (H(x)) for a.e.x∈[ 0, 2 π), we thus established Anderson localization on the spectrum up to the edges and the center. More general potentials than cosine can be treated, but only those energies with nonzero spectral density are allowed. Finally, we prove the same result for operators on the whole line with potential , where A:?2-->?2 is a hyperbolic toral automorphism, F∈C1(?2), ∫F= 0, and λ small. The basis for our analysis is an asymptotic formula for the Lyapunov exponent for λ--> 0 by Figotin-Pastur, and generalized by Chulaevski-Spencer. We combine this asymptotic expansion with certain martingale large deviation estimates in order to apply the methods developed by Bourgain and Goldstein in the quasi-periodic case.

  2. Superconducting pairing of interacting electrons: implications from the two-impurity Anderson model

    NASA Astrophysics Data System (ADS)

    Zhu, Lijun; Zhu, Jian-Xin

    2011-03-01

    We study the non-local superconducting pairing of two interacting Anderson impurities, which has an instability near the quantum critical point from the competition between the Kondo effect and an antiferromagnetic inter-impurity spin exchange interaction. As revealed by the dynamics over the whole energy range, the superconducting pairing fluctuations acquire considerable strength from an energy scale much higher than the characteristic spin fluctuation scale while the low energy behaviors follow those of the staggered spin susceptibility. We argue that the superconducting pairing might not need the spin fluctuations as the glue, but rather originated from the effective Coulomb interaction. On the other hand, critical spin fluctuations in the vicinity of quantum criticality are also crucial to a superconducting pairing instability, by preventing a Fermi liquid fixed point being reached to keep the superconducting pairing fluctuations finite at low energies. A superconducting order, to reduce the accumulated entropy carried by the critical degrees of freedom, may arise favorably from this instability. This work is supported by the U.S. DOE through the LANL/LDRD program.

  3. Non-conventional Anderson localization in a matched quarter stack with metamaterials

    NASA Astrophysics Data System (ADS)

    Torres-Herrera, E. J.; Izrailev, F. M.; Makarov, N. M.

    2013-05-01

    We study the problem of non-conventional Anderson localization emerging in bilayer periodic-on-average structures with alternating layers of materials, with positive and negative refraction indices na and nb. Attention is paid to the model of the so-called quarter stack with perfectly matched layers (the same unperturbed by disorder impedances, Za = Zb, and optical path lengths, nada = |nb|db, with da and db being the thicknesses of basic layers). As was recently numerically discovered, in such structures with weak fluctuations of refractive indices (compositional disorder), the localization length Lloc is enormously large in comparison to the conventional localization occurring in the structures with positive refraction indices only. In this paper we develop a new approach, which allows us to derive the expression for Lloc for weak disorder and any wave frequency ω. In the limit ω → 0 one gets a quite specific dependence, L-1loc∝σ4ω8, which is obtained within the fourth order of perturbation theory. We also analyze the interplay between two types of disorder, when in addition to the fluctuations of na and nb, the thicknesses da and db slightly fluctuate as well (positional disorder). We show how conventional localization recovers with the addition of positional disorder.

  4. Biomarkers and Imaging Findings of Anderson-Fabry Disease-What We Know Now.

    PubMed

    Beirão, Idalina; Cabrita, Ana; Torres, Márcia; Silva, Fernando; Aguiar, Patrício; Laranjeira, Francisco; Gomes, Ana Marta

    2017-06-11

    Anderson-Fabry disease (AFD) is an X-linked lysosomal storage disorder, caused by deficiency or absence of the alpha-galactosidase A activity, with a consequent glycosphingolipid accumulation. Biomarkers and imaging findings may be useful for diagnosis, identification of an organ involvement, therapy monitoring and prognosis. The aim of this article is to review the current available literature on biomarkers and imaging findings of AFD patients. An extensive bibliographic review from PubMed, Medline and Clinical Key databases was performed by a group of experts from nephrology, neurology, genetics, cardiology and internal medicine, aiming for consensus. Lyso-GB3 is a valuable biomarker to establish the diagnosis. Proteinuria and creatinine are the most valuable to detect renal damage. Troponin I and high-sensitivity assays for cardiac troponin T can identify patients with cardiac lesions, but new techniques of cardiac imaging are essential to detect incipient damage. Specific cerebrovascular imaging findings are present in AFD patients. Techniques as metabolomics and proteomics have been developed in order to find an AFD fingerprint. Lyso-GB3 is important for evaluating the pathogenic mutations and monitoring the response to treatment. Many biomarkers can detect renal, cardiac and cerebrovascular involvement, but none of these have proved to be important to monitoring the response to treatment. Imaging features are preferred in order to find cardiac and cerebrovascular compromise in AFD patients.

  5. Path to poor coherence in the periodic Anderson model from Mott physics and hybridization

    NASA Astrophysics Data System (ADS)

    Amaricci, A.; de'Medici, L.; Sordi, G.; Rozenberg, M. J.; Capone, M.

    2012-06-01

    We investigate the anomalous metal arising from hole-doping the Mott insulating state in the periodic Anderson model. Using dynamical mean-field theory we show that, as opposed to the electron-doped case, in the hole-doped regime the hybridization between localized and delocalized orbitals leads to the formation of composite quasiparticles reminiscent of the Zhang-Rice singlets. We compute the coherence temperature of this state, showing its extremely small value at low doping. As a consequence the weakly doped Mott state deviates from the predictions of Fermi-liquid theory already at small temperatures. The onset of the Zhang-Rice state and of the consequent poor coherence is due to the electronic structure in which both localized and itinerant carriers have to be involved in the formation of the conduction states and to the proximity to the Mott state. By investigating the magnetic properties of this state, we discuss the relation between the anomalous metallic properties and the behavior of the magnetic degrees of freedom.

  6. Successive superconducting transitions and Anderson localization effect in Ta2 S2 C

    NASA Astrophysics Data System (ADS)

    Walter, Jürgen; Suzuki, Itsuko S.; Suzuki, Masatsugu

    2004-08-01

    A complex carbide Ta2S2C consists of van der Waals (vdw)-bonded layers with a stacking sequence along the c axis: ⋯C-Ta-S-vdw-S-Ta-C-⋯ . The magnetic properties of this compound have been studied from dc and ac magnetic susceptibility. Ta2S2C undergoes successive superconducting transitions of a hierachical nature at Tcl=3.61±0.01K [ Hc1(l)(0)=28±2Oe and Hc2(l)(0)=7.7±0.2kOe ] and Tcu=8.9±0.1K [ Hc2(u)(0)=14.0±0.5kOe ]. The intermediate phase between Tcu and Tcl is an intragrain superconductive state occurring in the Ta-C layers in Ta2S2C . The low temperature phase below Tcl is an intergrain superconductive state. The magnetic susceptibility at H well above 10kOe is described by a sum of a diamagnetic susceptibility and a Curie-type behavior. The latter is due to the localized magnetic moments of conduction electrons associated with the Anderson localization effect, occurring in the 1T-TaS2 type structure in Ta2S2C .

  7. Effects of band filling in the Anderson-Falicov-Kimball model

    NASA Astrophysics Data System (ADS)

    Carvalho, Rubens D. B.; Gusmão, M. A.

    2013-02-01

    In this work, we study the Anderson-Falicov-Kimball model within the dynamical mean field theory for the Bethe lattice, restricting our analysis to the nonmagnetic case. The one-particle density of states is obtained by both arithmetic and geometric averages over disorder, since only the latter can detect localization in the absence of an energy gap. Varying the strengths of Coulomb interaction and disorder at zero temperature, we construct phase diagrams for this model, where we distinguish spectral regions with localized states, with extended states, or with a correlation-induced gap. With this, we identify metal-insulator transitions driven by correlation and disorder, as well as the competition between these effects. This is done for various band fillings, since our main interest here is to study how the variation of the electron density affects the phase diagrams previously obtained for half-filling. The picture revealed by the density of states is further checked by evaluating the static and dynamic conductivities, including temperature effects.

  8. Animal model of Sar1b deficiency presents lipid absorption deficits similar to Anderson Disease

    PubMed Central

    Levic, Daniel S.; Minkel, JR; Wang, Wen-Der; Rybski, Witold M.; Melville, David B.; Knapik, Ela W.

    2015-01-01

    Anderson Disease (ANDD) or Chylomicron Retention Disease (CMRD) is a rare, hereditary lipid malabsorption syndrome associated with mutations in the SAR1B gene that is characterized by failure to thrive and hypocholesterolemia. Although the SAR1B structure has been resolved and its role in formation of coat protein II (COPII) coated carriers is well established, little is known about the requirement for SAR1B during embryogenesis. To address this question, we have developed a zebrafish model of Sar1b deficiency based on antisense oligonucleotide knockdown. We show that zebrafish sar1b is highly conserved among vertebrates, broadly expressed during development, and enriched in the digestive tract organs, brain and craniofacial skeleton. Consistent with ANDD symptoms of chylomicron retention, we found that dietary lipids in Sar1b deficient embryos accumulate in enterocytes. Transgenic expression analysis revealed that Sar1b is required for growth of exocrine pancreas and liver. Furthermore, we found abnormal differentiation and maturation of craniofacial cartilage associated with defects in procollagen II secretion, and absence of select, neuroD-positive neurons of the midbrain and hindbrain. The model presented here will help to systematically dissect developmental roles of Sar1b and to discover molecular and cellular mechanisms leading to organ-specific ANDD pathology. PMID:25559265

  9. Figures-of-merit of Anderson localization cavities in membrane-based periodic-on-average random templates

    NASA Astrophysics Data System (ADS)

    Boddeti, Ashwin K.; Kumar, Randhir; Mujumdar, Sushil

    2017-08-01

    Anderson localization of light is an exotic mesoscopic phenomenon sustained in disordered systems through the self-interference of multiply scattered light. The localized modes are essentially eigenfunctions of the structural disorder, and define the resonances in the system. In this paper, we report on the computed figures-of-merit of Anderson cavities in two-dimensional membrane based structures, in which the disorder is written on a periodic-on-average template. We propose a disorder parameter that better reflects the randomization of the lattice points as compared to the conventionally used percentage disorder strength. Our results investigate the viability of such cavities in applications such as random lasing and cavity quantum electrodynamics.

  10. Versatility of Taylor Spatial Frame in Gustilo-Anderson III C femoral fractures: report of three cases.

    PubMed

    Sala, Francesco; Albisetti, Walter; Capitani, Dario

    2010-11-01

    Taylor Spatial Frame (TSF) combines a multiplanar external fixator and software accuracy for reduction of acute long-bone fractures. The frame gives stability, soft-tissue preservation, adjustability and functionality allowing bone to realize its full osteogenic potential. Three patients with multiple injuries and femoral Gustilo-Anderson type III C have been treated in our center. Initial surgery was performed within 6 h of injury with help of vascular surgeon. We used TSF as definitive fixation method. The results were assessed using the functional and radiological scoring system described by Paley and Maar. Fracture union occurred in all limbs and average fixation time was 151.6 days. All three patients had excellent outcome in terms of bony and functional ASAMI criteria. The TSF is a valuable tool. It is a definitive method of femoral Gustilo-Anderson type III C fracture care using external fixation with several advantages over previously used devices.

  11. Petrographic characteristics of the Wyodak-Anderson coal bed (Paleocene), Powder River Basin, Wyoming, U.S.A.

    USGS Publications Warehouse

    Warwick, P.D.; Stanton, R.W.

    1988-01-01

    Six lithofacies of the thick ( > 30 m) Wyodak-Anderson subbituminous coal bed of the Fort Union Formation (Paleocene), Powder River Basin, Wyoming, can be delimited using megascopic and petrographic data. Previous lithofacies analysis of the rock types associated with the Wyodak-Anderson bed suggested that raised peat accumulated in restricted parts of an inland flood plain. The peat bodies were separated by deposits of contemporaneous, possibly anastomosed channels. In this study, megascopic descriptions from four mine highwalls of the Wyodak-Anderson coal bed were found to be similar to facies defined by microscopic data from core and highwall samples. The data indicate that the upper and lower parts of the coal bed are rich in preserved wood remains (for instance, humotelinite), whereas the middle part of the bed contains comparatively larger amounts of material that resulted from degradation and comminution of the peat (e.g. eugelinite). The facies are interpreted to be the result of different chemical and biological environments at the time of peat formation. ?? 1988.

  12. [Heart involvement in Anderson-Fabry disease: Italian recommendations for diagnostic, follow-up and therapeutic management].

    PubMed

    Pieruzzi, Federico; Pieroni, Maurizio; Zachara, Elisabetta; Marziliano, Nicola; Morrone, Amelia; Cecchi, Franco

    2015-11-01

    Anderson-Fabry disease is a rare X-linked lysosomal storage disorder caused by mutations of the GLA gene that encodes alpha-galactosidase A. It is characterized by a multisystemic involvement: the renal, neurological, heart, cochleovestibular and cutaneous systems are the most damaged. Morbidity and mortality of Anderson-Fabry disease depend on renal insufficiency, heart failure and nervous system involvement. Left ventricular hypertrophy is the most common cardiac manifestation followed by conduction system disease, valve dysfunction, and arrhythmias. Mild to moderate left ventricular hypertrophy may simulate a non-obstructive hypertrophic cardiomyopathy. Management of Anderson-Fabry disease starting from the diagnosis of cardiac involvement, the prevention of complications, the therapeutic aspects, up to appropriate clinical follow-up, requires a multidisciplinary approach. According to recent management guidelines, only few evidence-based data are available to guide the clinical and therapeutic approach to this rare disease. An Italian Board, composed by nephrologists, cardiologists, geneticists, pediatricians and neurologists has been established in order to approve by consensus a diagnostic and therapeutic management protocol. The authors report the results of this cardiologic management consensus.

  13. Anderson-Hynes pyeloplasty with isthmotomy and lateropexy in horseshoe kidneys with pelviureteric junction obstruction in children

    PubMed Central

    Panda, Shasanka Shekhar; Bajpai, Minu; Jana, Manisha; Baidya, Dalim Kumar; Kumar, Rakesh

    2014-01-01

    Objective: The objective of this study was to evaluate the results of Anderson-Hynes pyeloplasty with isthmotomy and lateropexy in horseshoe kidney with pelviureteric junction obstruction (PUJO). Materials and Methods: Medical records of patients of horseshoe kidney with PUJO operated in our institute between June 1998 and June 2012 were reviewed. Anderson-Hynes pyeloplasty with isthmotomy and lateropexy was performed in all patients. The surgical outcome was evaluated with emphasis on the changes in degree of hydronephrosis by ultrasonography, renal drainage and function assessed by diuretic renal scans. Results: We studied the records of eight children of horseshoe kidney having unilateral PUJO. Obstruction was caused by a crossing lower-pole vessel in two cases, a high ureteral insertion in three and narrowing of the PUJ in three cases. Post-operative follow-up (median 4.4 years, range 18 months to 10 years) revealed improved renal function and good drainage in all cases. Hydronephrosis disappeared in 3, 4 showed Grade 1 and one showed Grade 2 hydronephrosis. All children are doing well and have no symptoms. Conclusion: Anderson-Hynes pyeloplasty with isthmotomy and lateropexy is a highly effective and safe procedure for treating PUJO in horseshoe kidney in children. PMID:24744513

  14. Full density-matrix numerical renormalization group calculation of impurity susceptibility and specific heat of the Anderson impurity model

    NASA Astrophysics Data System (ADS)

    Merker, L.; Weichselbaum, A.; Costi, T. A.

    2012-08-01

    Recent developments in the numerical renormalization group (NRG) allow the construction of the full density matrix (FDM) of quantum impurity models [see A. Weichselbaum and J. von Delft, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.99.076402 99, 076402 (2007)] by using the completeness of the eliminated states introduced by F. B. Anders and A. Schiller [F. B. Anders and A. Schiller, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.95.196801 95, 196801 (2005)]. While these developments prove particularly useful in the calculation of transient response and finite-temperature Green's functions of quantum impurity models, they may also be used to calculate thermodynamic properties. In this paper, we assess the FDM approach to thermodynamic properties by applying it to the Anderson impurity model. We compare the results for the susceptibility and specific heat to both the conventional approach within NRG and to exact Bethe ansatz results. We also point out a subtlety in the calculation of the susceptibility (in a uniform field) within the FDM approach. Finally, we show numerically that for the Anderson model, the susceptibilities in response to a local and a uniform magnetic field coincide in the wide-band limit, in accordance with the Clogston-Anderson compensation theorem.

  15. Anderson, S.C., Woman Gets Prison for Extensive Bank Fraud Scam and Environmental Crime Nancy Stein operated American Screw and Rivet Corporation which was also sentenced

    EPA Pesticide Factsheets

    ATLANTA - United States Attorney Bill Nettles stated late yesterday that Nancy Marie Stein, age 62, of Anderson, South Carolina , was sentenced by Senior United States District Judge Henry M. Herlong in federal court in Greenville, to a total of 73

  16. DMSP Auroral Charging at Solar Cycle 24 Maximum

    NASA Technical Reports Server (NTRS)

    Chandler, Michael; Parker, Linda Neergaard; Minow, Joseph I.

    2013-01-01

    It has been well established that polar orbiting satellites can experience mild to severe auroral charging levels (on the order of a few hundred volts to few kilovolts negative frame potentials) during solar minimum conditions (Frooninckx and Sojka, 1992; Anderson and Koons, 1996; Anderson, 2012). These same studies have shown a strong reduction in charging during the rising and declining phases of the past few solar cycles with a nearly complete suppression of auroral charging at solar maximum. Recently, we have observed examples of high level charging during the recent approach to Solar Cycle 24 solar maximum conditions not unlike those reported by Frooninckx and Sojka (1992). These observations demonstrate that spacecraft operations during solar maximum cannot be considered safe from auroral charging when solar activity is low. We present a survey of auroral charging events experienced by the Defense Meteorological Satellite Program (DMSP) F16 satellite during Solar Cycle 24 maximum conditions. We summarize the auroral energetic particle environment and the conditions necessary for charging to occur in this environment, we describe how the lower than normal solar activity levels for Solar Cycle 24 maximum conditions are conducive to charging in polar orbits, and we show examples of the more extreme charging events, sometimes exceeding 1 kV, during this time period.

  17. The pioneer woman's view of migraine: Elizabeth Garrett Anderson's thesis "Sur la migraine".

    PubMed

    Wilkinson, M; Isler, H

    1999-01-01

    This is a presentation of a doctoral thesis of 1870. The author was English but the thesis and the examinations were in French. Elizabeth Garrett Anderson, usually referred to as E.G.A., was the first woman in Britain to obtain the title of M.D., but not the first in Europe. Nadeshda Prokofevna Suslova, a Russian, received her M.D. in 1867 in Zurich, the most liberal university at that time, soon to be flooded by female students from Russia. E.G.A. had been applying to the few possible European universities but she settled for Paris after the Empress Eugenie had decided that she should be accepted there. This meant that she could succeed without having to be a Paris resident, just by writing a thesis and passing a series of examinations presided over by Paul Broca. This was important as she was already conducting private and dispensary practice, and could not find a locum (she insisted on a woman). E.G.A. had suffered many setbacks, for being a woman, as such being unacceptable in dissection rooms and operating theatres, and generally in a professional career where women were unheard of. She was finally permitted to receive her medical diploma from the Worshipful Society of Apothecaries of London. She wrote about her thesis: "I have chosen Headache as its subject. I had to find a subject which could be well studied without post-mortem observations, of which I can have but very few in either private or dispensary practice; and I wished also to take a large subject, one that demanded some insight into the harmony that exists between the main physiological functions." Marcia Wilkinson (M.W.), who worked in the Elizabeth Garrett Anderson Hospital in London for 35 years, heard there of E.G.A.'s thesis on migraine and sent for it from Paris. In 1966 she translated it into English from the original French, being interested both in the subject and in the person of this resolute and lucid woman. When H. Isler found the French thesis in the British Library he intended to

  18. On Planetary Evolution and the Evolution of Planetary Science During the Career of Don Anderson

    NASA Astrophysics Data System (ADS)

    Solomon, S. C.

    2003-12-01

    The planets of our solar system have long been viewed by Don Anderson as laboratories for testing general aspects of planetary evolution and as points of comparison to the Earth. I was fortunate to have been a student 39 years ago in a course at Caltech that Don taught with Bob Kovach on the interiors of the Earth and the planets. At that time, Mariner 4 had not yet flown by Mars, the lunar Ranger program was still in progress, and it was permissible to entertain the hypothesis that all of the terrestrial planets were identical in bulk composition. In the last four decades spacecraft have visited every planet from Mercury to Neptune; samples from the Moon, Mars, asteroids, and comets reside in our laboratories; and more than 100 planets have been discovered orbiting other stars. More importantly, traditionally distinct fields have merged to the point where planetary scientists must be conversant with the findings and modes of thinking from astronomy and biology as well as the geosciences. A few examples illustrate this confluence. Theoretical models for the structure of the atmospheres of gas-giant planets led to the first astronomical detection of an extrasolar planetary atmosphere for the transiting planet HD209458b. Although the atmospheric models were based on those for solar-system gas giants, the 3.5-day orbital period means that this planet is 100 times closer to its star than Jupiter is to the Sun, its effective temperature is 1100 K, and the detected signature of the planetary atmosphere was absorption by neutral sodium. Sodium in Mercury's exosphere, detected astronomically from Earth, figures into the question of how the terrestrial planets came to have distinct bulk compositions. Hypotheses to account for Mercury's high uncompressed density, and by inference its high ratio of metal to silicate, range from chemical gradients in the early solar nebula to preferential removal of silicates from a differentiated protoplanet by nebular heating or giant impact

  19. The University of Texas M.D. Anderson Cancer Center Proton Therapy Facility

    SciTech Connect

    Smith, Alfred; Newhauser, Wayne; Latinkic, Mitchell; Hay, Amy; Cox, James; McMaken, Bruce; Styles, John

    2003-08-26

    The University of Texas M.D. Anderson Cancer Center (MDACC), in partnership with Sanders Morris Harris Inc., a Texas-based investment banking firm, and The Styles Company, a developer and manager of hospitals and healthcare facilities, is building a proton therapy facility near the MDACC main complex at the Texas Medical Center in Houston, Texas USA. The MDACC Proton Therapy Center will be a freestanding, investor-owned radiation oncology center offering state-of-the-art proton beam therapy. The facility will have four treatment rooms: three rooms will have rotating, isocentric gantries and the fourth treatment room will have capabilities for both large and small field (e.g. ocular melanoma) treatments using horizontal beam lines. There will be an additional horizontal beam room dedicated to physics research and development, radiation biology research, and outside users who wish to conduct experiments using proton beams. The first two gantries will each be initially equipped with a passive scattering nozzle while the third gantry will have a magnetically swept pencil beam scanning nozzle. The latter will include enhancements to the treatment control system that will allow for the delivery of proton intensity modulation treatments. The proton accelerator will be a 250 MeV zero-gradient synchrotron with a slow extraction system. The facility is expected to open for patient treatments in the autumn of 2005. It is anticipated that 675 patients will be treated during the first full year of operation, while full capacity, reached in the fifth year of operation, will be approximately 3,400 patients per year. Treatments will be given up to 2-shifts per day and 6 days per week.

  20. Anderson-Stuart Model to Analyze DC Conductivity of Fluormica Glassceramics

    NASA Astrophysics Data System (ADS)

    Jogad, Mahantappa S.; Krishnamurthy, B. S.; Saraswati, V.

    2001-03-01

    The Glassceramics (GC) are essentially polycrystalline solids in the matrix of residual glass phase. They are interesting in view of the scientific and technological importance. The fluormica glass system (K2O MgO Al2O3 MgF2 B2O3 SiO2) was prepared for a specific composition by melt quench technique, and the fluormica GC phase was obtained by giving heat treatment at 1123 K to the glass sample [1]. The transition from glass to GC was confirmed using XRD. The fluormica are structural analogues of natural mica. Here the K+ ions are weakly cross-bonded in tetrahedral sheet. Fluormica exhibits an unusual combination of properties like machinability, resistance to withstand high temperatures, high dielectric constant with low loss, and high DC resistivity [2]. We have measured the DC conductivity (s) as a function of temperature (T) using the two-probe method. These measurements have been analyzed using the Anderson-Stuart (AS) model [3]. The Arrhenius plots of s vs T exhibit two linear regions, and the activation energy of the GC is found to be larger than that of glass [1]. The physical parameters selected to fit s vs T using the AS model which describes fairly well the ionic conduction in the fluormica glass system, are found to be reasonable. However, it appeared that a distribution of activation energies instead of single activation energy is necessary, to explain the experimental data. Dr Mahntappa S Jogad would like to acknowledge the American Physical Society’s Kilambi Ramavataram Committee and the Fulbright Foreign Scholarship Board, for a visiting fellowship. References: 1. M S Jogad, B S Krishnamurthy and V Saraswati, Asian Journal of Physics, 6, Nos, 142, 158 (1997) 2. Mahantappa S Jogad, B S Krishnamurthy and V Saraswati, J Non Crystalline Solids (Communicated). 3. M. D. Ingram, Phys. Chem. Glasses, 28, 215 (1987).

  1. Survival of patients with metastatic leiomyosarcoma: the MD Anderson Clinical Center for targeted therapy experience.

    PubMed

    Wang, Zhijie; Shi, Naiyi; Naing, Aung; Janku, Filip; Subbiah, Vivek; Araujo, Dejka M; Patel, Shreyaskumar R; Ludwig, Joseph A; Ramondetta, Lois M; Levenback, Charles F; Ramirez, Pedro T; Piha-Paul, Sarina A; Hong, David; Karp, Daniel D; Tsimberidou, Apostolia M; Meric-Bernstam, Funda; Fu, Siqing

    2016-12-01

    Advanced stage leiomyosarcoma (LMS) is incurable with current systemic antitumor therapies. Therefore, there is clinical interest in exploring novel therapeutic regimens to treat LMS. We reviewed the medical records of 75 consecutive patients with histologically confirmed metastatic LMS, who had been referred to the Clinical Center for Targeted Therapy at MD Anderson Cancer Center. To lay the foundation for potential phase I trials for the treatment of advanced LMS, we analyzed tumor response and survival outcome data. The frequent hotspot gene aberrations that we observed were the TP53 mutation (65%) and RB1 loss/mutation (45%) detected by Sequenom or next-generation sequencing. Among patients treated with gene aberration-related phase I trial therapy, the median progression-free survival was 5.8 months and the median overall survival was 15.9 months, significantly better than in patients without therapy (1.9 months, P = 0.001; and 8.7 months, P = 0.013, respectively). Independent risk factors that predicted shorter overall survival included hemoglobin <10 g/dL, body mass index <30 kg/m(2) , serum albumin <3.5 g/dL, and neutrophil above upper limit of normal. The median survivals were 19.9, 7.6, and 0.9 months for patients with 0, 1 or 2, and ≥3 of the above risk factors, respectively (P < 0.001). A prognostic scoring system that included four independent risk factors might predict survival in patients with metastatic LMS who were treated in a phase I trial. Gene aberration-related therapies led to significantly better clinical benefits, supporting that further exploration with novel mechanism-driven therapeutic regimens is warranted.

  2. Clinical Features, Diagnosis, and Management of Patients With Anderson-Fabry Cardiomyopathy.

    PubMed

    Yogasundaram, Haran; Kim, Daniel; Oudit, Omar; Thompson, Richard B; Weidemann, Frank; Oudit, Gavin Y

    2017-07-01

    Anderson-Fabry disease (AFD) is an X-linked recessive, multisystem disease of lysosomal storage. A mutation in the gene encoding the hydrolase enzyme α-galactosidase A results in its deficiency, or complete absence of activity. Subsequent progressive intracellular accumulation of glycosphingolipids, predominantly globotriaosylceramide, in various tissues, results in progressive organ dysfunction and failure, most commonly affecting the kidneys, nervous system, skin, eyes, vascular endothelium, and the heart. Cardiac involvement in AFD represents a leading cause of morbidity and mortality. Globotriaosylceramide accumulation affects cardiomyocytes, smooth muscle cells, vascular endothelial cells, and fibroblasts leading to various pathologies including valvular regurgitation, conduction disease and arrhythmias, coronary microvascular dysfunction, and right and left ventricular hypertrophy (LVH) leading to early diastolic dysfunction and late-stage systolic impairment. Diagnosis is on the basis of decreased plasma α-galactosidase activity in men and positive genetic testing in women. Contemporary large-scale screening studies have revealed a prevalence of 1%-5% in patients with unexplained LVH in multiple cohorts. Cardiac magnetic resonance imaging, with its unique tissue characterization capabilities, is the most important imaging modality to assess for cardiomyopathy in patients with AFD. Enzyme replacement therapy is indicated in AFD patients with significant organ involvement, and has been shown to clear sphingolipids from endothelial cells in other organs, as well as to reduce left ventricular mass as early as 6 months after starting treatment. There is increasing evidence that enzyme replacement therapy might be more effective if given at earlier stages of disease, before the development of LVH and myocardial fibrosis. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  3. Genetic Screening of Anderson-Fabry Disease in Probands Referred From Multispecialty Clinics.

    PubMed

    Favalli, Valentina; Disabella, Eliana; Molinaro, Mariadelfina; Tagliani, Marilena; Scarabotto, Anna; Serio, Alessandra; Grasso, Maurizia; Narula, Nupoor; Giorgianni, Carmela; Caspani, Clelia; Concardi, Monica; Agozzino, Manuela; Giordano, Calogero; Smirnova, Alexandra; Kodama, Takahide; Giuliani, Lorenzo; Antoniazzi, Elena; Borroni, Riccardo G; Vassallo, Camilla; Mangione, Filippo; Scelsi, Laura; Ghio, Stefano; Pellegrini, Carlo; Zedde, Marialuisa; Fancellu, Laura; Sechi, GianPietro; Ganau, Antonello; Piga, Stefania; Colucci, Annarita; Concolino, Daniela; Di Mascio, Maria Teresa; Toni, Danilo; Diomedi, Marina; Rapezzi, Claudio; Biagini, Elena; Marini, Massimiliano; Rasura, Maurizia; Melis, Maurizio; Nucera, Antonia; Guidetti, Donata; Mancuso, Michelangelo; Scoditti, Umberto; Cassini, Pamela; Narula, Jagat; Tavazzi, Luigi; Arbustini, Eloisa

    2016-09-06

    Anderson-Fabry disease (AFD) is a rare X-linked lysosomal storage disease, caused by defects of the alpha-galactosidase A (GLA) gene. AFD can affect the heart, brain, kidney, eye, skin, peripheral nerves, and gastrointestinal tract. Cardiology (hypertrophic cardiomyopathy), neurology (cryptogenic stroke), and nephrology (end-stage renal failure) screening studies suggest the prevalence of GLA variants is 0.62%, with diagnosis confirmation in 0.12%. This study sought to expand screening from these settings to include ophthalmology, dermatology, gastroenterology, internal medicine, pediatrics, and medical genetics to increase diagnostic yield and comprehensively evaluate organ involvement in AFD patients. In a 10-year prospective multidisciplinary, multicenter study, we expanded clinical, genetic, and biochemical screening to consecutive patients enrolled from all aforementioned clinical settings. We tested the GLA gene and α-galactosidase A activity in plasma and leukocytes. Inclusion criteria comprised phenotypical traits and absence of male-to-male transmission. Screening was extended to relatives of probands harboring GLA mutations. Of 2,034 probands fulfilling inclusion criteria, 37 (1.8%) were carriers of GLA mutations. Cascade family screening identified 60 affected relatives; clinical data were available for 4 affected obligate carriers. Activity of α-galactosidase A in plasma and leukocytes was diagnostic in male subjects, but not in female subjects. Of the 101 family members harboring mutations, 86 were affected, 10 were young healthy carriers, and 5 refused clinical evaluation. In the 86 patients, involved organs or organ systems included the heart (69%), peripheral nerves (46%), kidney (45%), eye (37%), brain (34%), skin (32%), gastrointestinal tract (31%), and auditory system (19%). Globotriaosylceramide accumulated in organ-specific and non-organ-specific cells in atypical and classic variants, respectively. Screening probands with clinically

  4. Cancer-related symptom assessment in France: validation of the French M. D. Anderson Symptom Inventory.

    PubMed

    Guirimand, Frédéric; Buyck, Jean-François; Lauwers-Allot, Elisabeth; Revnik, Julia; Kerguen, Thierry; Aegerter, Philippe; Brasseur, Louis; Cleeland, Charles S

    2010-04-01

    This multicenter study was intended to validate the French version of the M. D. Anderson Symptom Inventory (MDASI-Fr) in French cancer patients (n=162) with solid tumors or hematological malignancies. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) was used as a part of the validation. Factor analysis showed three underlying constructs for symptom items: general symptoms (pain, fatigue, disturbed sleep, shortness of breath, drowsiness, dry mouth, and numbness or tingling items); emotional and cognitive components (distress, sadness, and remembering items); and a gastrointestinal component (nausea, vomiting, and lack of appetite items), with Cronbach's alphas of 0.79, 0.73, and 0.71, respectively. Convergent validity was established by comparing MDASI-Fr items with the EORTC QLQ-C30 scale and the Brief Pain Inventory (BPI). Overall, the 19-item MDASI-Fr score correlated well with the QLQ-C30 global health status, and the pain item of the MDASI-Fr was highly correlated with the short form of the BPI. The most prevalent symptoms were fatigue, distress, dry mouth, and pain. Twenty-five percent of patients reported moderate or severe pain (numeric rating scale >4 on 0-10 severity ratings). Physician ratings of global change on a second visit were significantly associated with changes in patient ratings on the MDASI-Fr, supporting the sensitivity of the measure. Symptoms interfered most with work and general activity. The MDASI-Fr is a valid and reliable tool for measuring symptom severity and interference in French cancer patients. Copyright (c) 2010 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

  5. Incidence of Atypical Femur Fractures in Cancer Patients: The MD Anderson Cancer Center Experience.

    PubMed

    Edwards, Beatrice J; Sun, Ming; West, Dennis P; Guindani, Michele; Lin, Yan Heather; Lu, Huifang; Hu, Mimi; Barcenas, Carlos; Bird, Justin; Feng, Chun; Saraykar, Smita; Tripathy, Debasish; Hortobagyi, Gabriel N; Gagel, Robert; Murphy, William A

    2016-08-01

    Atypical femoral fractures (AFFs) are rare adverse events attributed to bisphosphonate (BP) use. Few cases of AFF in cancer have been described; the aim of this study is to identify the incidence and risk factors for AFF in a large cancer center. This retrospective study was conducted at the MD Anderson Cancer Center. The incidence rate of AFF among BP users was calculated from January 1, 2004 through December 31, 2013. The control group (n = 51) included 2 or 3 patients on BPs matched for age (≤1 year) and gender. Logistic regression analysis was used to assess the relationship between clinical characteristics and AFF. Twenty-three AFF cases were identified radiographically among 10,587 BP users, the total BP exposure was 53,789 months (4482 years), and the incidence of AFF in BP users was 0.05 cases per 100,000 person-years. Meanwhile, among 300,553 patients who did not receive BPs there were 2 cases of AFF as compared with the 23 cases noted above. The odds ratio (OR) of having AFF in BP users was 355.58 times higher (95% CI, 84.1 to 1501.4, p < 0.0001) than the risk in non-BP users. The OR of having AFF in alendronate users was 5.54 times greater (OR 5.54 [95% CI, 1.60 to 19.112, p = 0.007]) than the odds of having AFF among other BP users. Patients who were on zoledronic acid (ZOL) had smaller odds of developing AFF compared with other BP users in this matched case control sample. AFFs are rare, serious adverse events that occur in patients with cancer who receive BP therapy. Patients with cancer who receive BPs for prior osteoporosis therapy or for metastatic cancer are at higher risk of AFF. © 2016 American Society for Bone and Mineral Research.

  6. Cycle Analysis

    SciTech Connect

    Wright, Steven A.

    2012-03-20

    1. The Cycle Analysis code is an Microsoft Excel code that performs many different types of thermodynamic cycle analysis for power producing systems. The code will calculate the temperature and pressure and all other thermodynamic properties at the inlet and outlet of each component. The code also calculates the power that is produced, the efficiency, and the heat transported in the heater, gas chiller and recuperators. The code provides a schematic of the loop and provides the temperature and pressure at each location in the loop. The code also provides a T-S (temperature-entropy) diagram of the loop and often it provides an pressure enthalpy plot as well. 2. This version of the code concentrates on supercritical CO2 power cycles, but by simply changing the name of the working fluid many other types of fluids can be analyzed. The Cycle Analysis code provided here contains 18 different types of power cycles. Each cycle is contained in one worksheet or tab that the user can select. The user can change the yellow highlighted regions to perform different thermodynamic cycle analysis.

  7. Commensurability effects in one-dimensional Anderson localization: Anomalies in eigenfunction statistics

    NASA Astrophysics Data System (ADS)

    Kravtsov, V. E.; Yudson, V. I.

    2011-07-01

    The one-dimensional (1d) Anderson model (AM), i.e. a tight-binding chain with random uncorrelated on-site energies, has statistical anomalies at any rational point f=2a/λE, where a is the lattice constant and λE is the de Broglie wavelength. We develop a regular approach to anomalous statistics of normalized eigenfunctions ψ( r) at such commensurability points. The approach is based on an exact integral transfer-matrix equation for a generating function Φr( u, ϕ) ( u and ϕ have a meaning of the squared amplitude and phase of eigenfunctions, r is the position of the observation point). This generating function can be used to compute local statistics of eigenfunctions of 1d AM at any disorder and to address the problem of higher-order anomalies at f={p}/{q} with q > 2. The descender of the generating function Pr(ϕ)≡Φr(u=0,ϕ) is shown to be the distribution function of phase which determines the Lyapunov exponent and the local density of states. In the leading order in the small disorder we derived a second-order partial differential equation for the r-independent ("zero-mode") component Φ( u, ϕ) at the E = 0 ( f={1}/{2}) anomaly. This equation is nonseparable in variables u and ϕ. Yet, we show that due to a hidden symmetry, it is integrable and we construct an exact solution for Φ( u, ϕ) explicitly in quadratures. Using this solution we computed moments Im = N<∣ ψ∣ 2 m> ( m ⩾ 1) for a chain of the length N → ∞ and found an essential difference between their m-behavior in the center-of-band anomaly and for energies outside this anomaly. Outside the anomaly the "extrinsic" localization length defined from the Lyapunov exponent coincides with that defined from the inverse participation ratio ("intrinsic" localization length). This is not the case at the E = 0 anomaly where the extrinsic localization length is smaller than the intrinsic one. At E = 0 one also observes an anomalous enhancement of large moments compatible with existence of yet

  8. The magnetocaloric effect with critical behavior of a periodic Anderson-like organic polymer.

    PubMed

    Ding, L J; Zhong, Y; Fan, S W; Zhu, L Y

    2016-01-07

    We study the magnetocaloric effect and the critical behavior of a periodic Anderson-like organic polymer using Green's function theory, in which the localized f orbitals hybridize with the conduction orbitals at even sites. The field-induced metal-insulator transitions with the magnetic Grüneisen parameter showing |Γh|∼T(-1) power-law critical behaviour are revealed, which provides a new thermodynamic means for probing quantum phase transitions. It is found that the competition of up-spin and down-spin hole excitations is responsible for the double peak structure of magnetic entropy change (-ΔS) for the dominant Kondo coupling case, implying a double magnetic cooling process via demagnetization, which follows a power law dependence of the magnetic field h: -ΔS∼h(n). The local exponent n tends to 1 and 2 below and above TC, while has a minimum of 0.648 at TC, which is in accordance with the experimental observation of perovskite manganites Pr0.55Sr0.45MnO3 and Nd0.55Sr0.45MnO3 (J. Y. Fan et al., Appl. Phys. Lett., 2011, 98, 072508; Europhys. Lett., 2015, 112, 17005) corresponding to the conventional ferromagnets within the mean field theory -ΔS∼h(2/3). At TC, the -ΔS∼h curves with a convex curvature superpose each other for small V values, which are separated by the large V case, distinguishing the RKKY interaction and Kondo coupling explicitly. Furthermore, the critical scaling law n(TC) = 1 + (β- 1)/(β + γ) = 1 + 1/δ(1 - 1/β) is related to the critical exponents (β, γ, and δ) extracted from the Arrott-Noakes equation of state and the Kouvel-Fisher method, which fulfill the Widom scaling relation δ = 1 + γβ(-1), indicating the self-consistency and reliability of the obtained results. In addition, based on the scaling hypothesis through checking the scaling analysis of magnetization, the M-T-h curves collapse into two independent universal branches below and above TC.

  9. Intraoperative Diagnosis of Anderson-Fabry Disease in Patients With Obstructive Hypertrophic Cardiomyopathy Undergoing Surgical Myectomy.

    PubMed

    Cecchi, Franco; Iascone, Maria; Maurizi, Niccolò; Pezzoli, Laura; Binaco, Irene; Biagini, Elena; Fibbi, Maria Laura; Olivotto, Iacopo; Pieruzzi, Federico; Fruntelata, Ana; Dorobantu, Lucian; Rapezzi, Claudio; Ferrazzi, Paolo

    2017-08-09

    Diagnostic screening for Anderson-Fabry cardiomyopathy (AFC) is performed in the presence of specific clinical red flags in patients with hypertrophic cardiomyopathy (HCM) older than 25 years. However, left ventricular outflow tract obstruction (LVOTO) has been traditionally considered an exclusion criteria for AFC. To examine a series of patients diagnosed with HCM and severe basal LVOTO undergoing myectomy in whom the diagnosis of AFC was suspected by the cardiac surgeon intraoperatively and confirmed by histological and genetic examinations. This retrospective analysis of patients undergoing surgical septal reduction strategies was conducted in 3 European tertiary referral centers for HCM from July 2013 to December 2016. Patients with a clinical diagnosis of obstructive HCM referred for surgical management of LVOTO were observed for at least 18 months after the procedure (mean [SD] follow-up, 33 [14] months). Etiology of patients with HCM who underwent surgical myectomy. From 2013, 235 consecutive patients with a clinical diagnosis of HCM underwent septal myectomy. The cardiac surgeon suspected a storage disease in 3 patients (1.3%) while inspecting their heart samples extracted from myectomy. The mean (SD) age at diagnosis for these 3 patients was 42 (4) years; all were male. None of the 3 patients presented with extracardiac features suggestive of AFC. All patients showed asymmetrical left ventricular hypertrophy, with maximal left ventricular thickness in the basal septum (19-31 mm), severe basal LVOTO (70-120 mm Hg), and left atrial dilatation (44-57 mm). Only 1 patient presented with late gadolinium enhancement on cardiovascular magnetic resonance at the right ventricle insertion site. The mean (SD) age at surgical procedure was 63 (5) years. On tactile sensation, the surgeon felt a spongy consistency of the surgical samples, different from the usual stony-elastic consistency typical of classic HCM, and this prompted histological examinations. Histology

  10. Non-equilibrium STLS approach to transport properties of single impurity Anderson model

    SciTech Connect

    Rezai, Raheleh Ebrahimi, Farshad

    2014-04-15

    In this work, using the non-equilibrium Keldysh formalism, we study the effects of the electron–electron interaction and the electron-spin correlation on the non-equilibrium Kondo effect and the transport properties of the symmetric single impurity Anderson model (SIAM) at zero temperature by generalizing the self-consistent method of Singwi, Tosi, Land, and Sjolander (STLS) for a single-band tight-binding model with Hubbard type interaction to out of equilibrium steady-states. We at first determine in a self-consistent manner the non-equilibrium spin correlation function, the effective Hubbard interaction, and the double-occupancy at the impurity site. Then, using the non-equilibrium STLS spin polarization function in the non-equilibrium formalism of the iterative perturbation theory (IPT) of Yosida and Yamada, and Horvatic and Zlatic, we compute the spectral density, the current–voltage characteristics and the differential conductance as functions of the applied bias and the strength of on-site Hubbard interaction. We compare our spectral densities at zero bias with the results of numerical renormalization group (NRG) and depict the effects of the electron–electron interaction and electron-spin correlation at the impurity site on the aforementioned properties by comparing our numerical result with the order U{sup 2} IPT. Finally, we show that the obtained numerical results on the differential conductance have a quadratic universal scaling behavior and the resulting Kondo temperature shows an exponential behavior. -- Highlights: •We introduce for the first time the non-equilibrium method of STLS for Hubbard type models. •We determine the transport properties of SIAM using the non-equilibrium STLS method. •We compare our results with order-U2 IPT and NRG. •We show that non-equilibrium STLS, contrary to the GW and self-consistent RPA, produces the two Hubbard peaks in DOS. •We show that the method keeps the universal scaling behavior and correct

  11. Variable induction of vitellogenin genes in the varroa mite, Varroa destructor (Anderson & Trueman), by the honeybee, Apis mellifera L, host and its environment.

    PubMed

    Cabrera Cordon, A R; Shirk, P D; Duehl, A J; Evans, J D; Teal, P E A

    2013-02-01

    Transcript levels of vitellogenins (Vgs) in the varroa mite, Varroa destructor (Anderson & Trueman), were variably induced by interactions between the developing honeybee, Apis mellifera L, as a food source and the capped honeybee cell environment. Transcripts for two Vgs of varroa mites were sequenced and putative Vg protein products characterized. Sequence analysis of VdVg1 and VdVg2 proteins showed that each had greater similarity with Vg1 and Vg2 proteins from ticks, respectively, than between themselves and were grouped separately by phylogenetic analyses. This suggests there was a duplication of the ancestral acarine Vg gene prior to the divergence of the mites and ticks. Low levels of transcript were detected in immature mites, males and phoretic females. Following cell invasion by phoretic females, VdVg1 and VdVg2 transcript levels were up-regulated after cell capping to a maximum at the time of partial cocoon formation by the honeybee. During oviposition the two transcripts were differentially expressed with higher levels of VdVg2 being observed. A bioassay based on assessing the transcript levels was established. Increases in VdVg1 and VdVg2 transcripts were induced experimentally in phoretic females when they were placed inside a cell containing an early metamorphosing last instar bee but not when exposed to the metamorphosing bee alone. The variable response of Vg expression to the food source as well as environmental cues within the capped cell demonstrates that perturbation of host-parasite interactions may provide avenues to disrupt the reproductive cycle of the varroa mites and prevent varroasis. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  12. Menstrual Cycle

    MedlinePlus

    ... to the Professional version Home Women's Health Issues Biology of the Female Reproductive System Menstrual Cycle Follicular ... Version. DOCTORS: Click here for the Professional Version Biology of the Female Reproductive System Overview of the ...

  13. Persistence of energy-dependent localization in the Anderson-Hubbard model with increasing system size and doping

    NASA Astrophysics Data System (ADS)

    Daley, P.; Wortis, R.

    2016-05-01

    Non-interacting systems with bounded disorder have been shown to exhibit sharp density of state peaks at the band edge which coincide with an energy range of abruptly suppressed localization. Recent work has shown that these features also occur in the presence of on-site interactions in ensembles of two-site Anderson-Hubbard systems at half filling. Here we demonstrate that this effect in interacting systems persists away from half filling, and moreover that energy regions with suppressed localization continue to appear in ensembles of larger systems despite a loss of sharp features in the density of states.

  14. Nuclear liability insurance: the Price-Anderson reparations system and the claims experience of the nuclear industry

    SciTech Connect

    Marrone, J.

    1983-01-01

    The manner in which the Price-Anderson Law operates to provide reparations is reviewed, and the changes made in the law by Congress in 1975 are outlined. Nuclear liability insurers' response to the Three Mile Island accident is described, including emergency assistance funds advanced to qualified evacuees and the claims and litigations that followed. Other nuclear liability claims that have been asserted are described as being brought chiefly by onsite workers. Good health physics protection of workers is acknowledged, but the need to improve record keeping for transient workers is stressed. The nuclear industry is urged to implement a more effective record-keeping program for such workers.

  15. Functional form of the Parisi overlap distribution for the three-dimensional Edwards-Anderson Ising spin glass.

    PubMed

    Berg, Bernd A; Billoire, Alain; Janke, Wolfhard

    2002-04-01

    Recently, it has been conjectured that the statistics of extremes is of relevance for a large class of correlated systems. For certain probability densities this predicts the characteristic large x falloff behavior f(x) approximately exp(-ae(x)), a>0. Using a multicanonical Monte Carlo technique, we have measured the Parisi overlap distribution P(q) for the three-dimensional Edward-Anderson Ising spin glass at and below the critical temperature We find that a probability distribution related to extreme-order statistics gives an excellent description of P(q) over about 80 orders of magnitude.

  16. Bi-stability in single impurity Anderson model with strong electron-phonon interaction(polaron regime)

    NASA Astrophysics Data System (ADS)

    Eskandari-asl, Amir

    2016-09-01

    We consider a single impurity Anderson model (SIAM) in which the quantum dot(QD) is strongly coupled to a phonon bath in polaron regime. This coupling results in an effective e-e attraction. By computing the self energies using a current conserving approximation which is up to second order in this effective attraction, we show that if the interaction is strong enough, in non particle-hole (PH) symmetric case, the system would be bi-stable and we have hysteresis loop in the I-V characteristic. Moreover, the system shows negative differential conductance in some bias voltage intervals.

  17. Joint min-max distribution and Edwards-Anderson's order parameter of the circular 1/f-noise model

    NASA Astrophysics Data System (ADS)

    Cao, Xiangyu; Le Doussal, Pierre

    2016-05-01

    We calculate the joint min-max distribution and the Edwards-Anderson's order parameter for the circular model of 1/f-noise. Both quantities, as well as generalisations, are obtained exactly by combining the freezing-duality conjecture and Jack-polynomial techniques. Numerical checks come with significantly improved control of finite-size effects in the glassy phase, and the results convincingly validate the freezing-duality conjecture. Application to diffusive dynamics is discussed. We also provide a formula for the pre-factor ratio of the joint/marginal Carpentier-Le Doussal tail for minimum/maximum which applies to any logarithmic random energy model.

  18. Ferromagnetic ordering in Mn-doped quantum wells GaAs-AlGaAs resulting from the virtual Anderson transition

    SciTech Connect

    Agrinskaya, N. V.; Berezovets, V. A.; Bouravlev, A.; Kozub, V. I.

    2014-08-20

    We present our results obtained for Mn-doped GaAs quantum wells where the evidences of the ferromagnetic transition at relatively high temperatures were found at unusually small Mn concentrations. The observed values of hopping resistance at small temperatures evidenced that the samples are deep in the insulating regime. Thus the corresponding estimates of the overlapping integrals can hardly explain the large values of Curie temperatures T{sub c} ≃ 100 K. We develop a theoretical model qualitatively explaining the experimental results basing on the concept of virtual Anderson transition.

  19. Exact solution for eigenfunction statistics at the center-of-band anomaly in the Anderson localization model

    NASA Astrophysics Data System (ADS)

    Kravtsov, V. E.; Yudson, V. I.

    2010-11-01

    An exact solution is found for the problem of the center-of-band (E=0) anomaly in the one-dimensional Anderson model of localization. By deriving and solving an equation for the generating function Φ(u,ϕ) we obtained an exact expression in quadratures for statistical moments Iq=⟨|ψE(r)|2q⟩ of normalized wave functions ψE(r) which show violation of one-parameter scaling and emergence of an additional length scale at E≈0 .

  20. Numerical renormalization group calculation of near-gap peaks in spectral functions of the Anderson model with superconducting leads

    NASA Astrophysics Data System (ADS)

    Hecht, T.; Weichselbaum, A.; von Delft, J.; Bulla, R.

    2008-07-01

    We use the numerical renormalization group method (NRG) to investigate a single-impurity Anderson model with a coupling of the impurity to a superconducting host. Analysis of the energy flow shows that, contrary to previous belief, NRG iterations can be performed up to a large number of sites, corresponding to energy differences far below the superconducting gap Δ. This allows us to calculate the impurity spectral function A(ω) very accurately for frequencies |ω|~Δ, and to resolve, in a certain parameter regime, sharp peaks in A(ω) close to the gap edge.

  1. Cycling injuries.

    PubMed Central

    Cohen, G. C.

    1993-01-01

    Bicycle-related injuries have increased as cycling has become more popular. Most injuries to recreational riders are associated with overuse or improper fit of the bicycle. Injuries to racers often result from high speeds, which predispose riders to muscle strains, collisions, and falls. Cyclists contact bicycles at the pedals, seat, and handlebars. Each is associated with particular cycling injuries. Images Figure 1 Figure 3 Figure 4 Figure 5 PMID:8471908

  2. Vapor Compression Cycle Design Program (CYCLE_D)

    National Institute of Standards and Technology Data Gateway

    SRD 49 NIST Vapor Compression Cycle Design Program (CYCLE_D) (PC database for purchase)   The CYCLE_D database package simulates the vapor compression refrigeration cycles. It is fully compatible with REFPROP 9.0 and covers the 62 single-compound refrigerants . Fluids can be used in mixtures comprising up to five components.

  3. Anderson localization in the non-Hermitian Aubry-André-Harper model with physical gain and loss

    NASA Astrophysics Data System (ADS)

    Zeng, Qi-Bo; Chen, Shu; Lü, Rong

    2017-06-01

    We investigate the Anderson localization in non-Hermitian Aubry-André-Harper (AAH) models with imaginary potentials added to lattice sites to represent the physical gain and loss during the interacting processes between the system and environment. By checking the mean inverse participation ratio (MIPR) of the system, we find that different configurations of physical gain and loss have very different impacts on the localization phase transition in the system. In the case with balanced physical gain and loss added in an alternate way to the lattice sites, the critical region (in the case with p -wave superconducting pairing) and the critical value (both in the situations with and without p -wave pairing) for the Anderson localization phase transition will be significantly reduced, which implies an enhancement of the localization process. However, if the system is divided into two parts with one of them coupled to physical gain and the other coupled to the corresponding physical loss, the transition process will be impacted only in a very mild way. Besides, we also discuss the situations with imbalanced physical gain and loss and find that the existence of random imaginary potentials in the system will also affect the localization process while constant imaginary potentials will not.

  4. Verification of Anderson Superexchange in MnO via Magnetic Pair Distribution Function Analysis and ab initio Theory

    NASA Astrophysics Data System (ADS)

    Frandsen, Benjamin A.; Brunelli, Michela; Page, Katharine; Uemura, Yasutomo J.; Staunton, Julie B.; Billinge, Simon J. L.

    2016-05-01

    We present a temperature-dependent atomic and magnetic pair distribution function (PDF) analysis of neutron total scattering measurements of antiferromagnetic MnO, an archetypal strongly correlated transition-metal oxide. The known antiferromagnetic ground-state structure fits the low-temperature data closely with refined parameters that agree with conventional techniques, confirming the reliability of the newly developed magnetic PDF method. The measurements performed in the paramagnetic phase reveal significant short-range magnetic correlations on a ˜1 nm length scale that differ substantially from the low-temperature long-range spin arrangement. Ab initio calculations using a self-interaction-corrected local spin density approximation of density functional theory predict magnetic interactions dominated by Anderson superexchange and reproduce the measured short-range magnetic correlations to a high degree of accuracy. Further calculations simulating an additional contribution from a direct exchange interaction show much worse agreement with the data. The Anderson superexchange model for MnO is thus verified by experimentation and confirmed by ab initio theory.

  5. Verification of Anderson superexchange in MnO via magnetic pair distribution function analysis and ab initio theory

    DOE PAGES

    Benjamin A. Frandsen; Brunelli, Michela; Page, Katharine; ...

    2016-05-11

    Here, we present a temperature-dependent atomic and magnetic pair distribution function (PDF) analysis of neutron total scattering measurements of antiferromagnetic MnO, an archetypal strongly correlated transition-metal oxide. The known antiferromagnetic ground-state structure fits the low-temperature data closely with refined parameters that agree with conventional techniques, confirming the reliability of the newly developed magnetic PDF method. The measurements performed in the paramagnetic phase reveal significant short-range magnetic correlations on a ~1 nm length scale that differ substantially from the low-temperature long-range spin arrangement. Ab initio calculations using a self-interaction-corrected local spin density approximation of density functional theory predict magnetic interactions dominatedmore » by Anderson superexchange and reproduce the measured short-range magnetic correlations to a high degree of accuracy. Further calculations simulating an additional contribution from a direct exchange interaction show much worse agreement with the data. Furthermore, the Anderson superexchange model for MnO is thus verified by experimentation and confirmed by ab initio theory.« less

  6. Inter-familial and intra-familial phenotypic variability in three Sicilian families with Anderson-Fabry disease.

    PubMed

    Tuttolomondo, Antonino; Simonetta, Irene; Duro, Giovanni; Pecoraro, Rosaria; Miceli, Salvatore; Colomba, Paolo; Zizzo, Carmela; Nucera, Antonia; Daidone, Mario; Di Chiara, Tiziana; Scaglione, Rosario; Della Corte, Vittoriano; Corpora, Francesca; Vogiatzis, Danai; Pinto, Antonio

    2017-09-22

    Anderson-Fabry disease (AFD) is an inborn lysosomal enzymopathy resulting from the deficient or absent activity of the lysosomal exogalactohydrolase, α-galactosidase A. This deficiency, results in the altered metabolism of glycosphingolipids which leads to their accumulation in lysosomes, thus to cellular and vascular dysfunction. To date, numerous mutations (according to recent data more than 1000 mutations) have been reported in the GLA intronic and exonic mutations. Traditionally, clinical manifestations are more severe in affected hemizygous males than in females. Nevertheless, recent studies have described severe organ dysfunction in women. This study reports clinical, biochemical, and molecular findings of the members of three Sicilian families. The clinical history of these patients highlights a remarkable interfamilial and intrafamilial phenotypic variability which characterizes Fabry disease relative to target organs and severity of clinical manifestations. Our findings, in agreement with previous data, report a little genotype-phenotype correlation for the disease, suggesting that the wide phenotypic variability of Anderson-Fabry disease is not completely ascribable to different gene mutations but other factors and mechanisms seem to be involved in the pathogenesis and clinical expression of the disease. Moreover, this study emphasies the importance of pedigree analysis in the family of each proband for identifying other possibly affected relatives.

  7. Development of the M. D. Anderson Cancer Center Gynecologic Applicators for the Treatment of Cervical Cancer: Historical Analysis

    SciTech Connect

    Yordy, John S.; Almond, Peter R.; Delclos, Luis

    2012-03-15

    Purpose: To provide historical background on the development and initial studies of the gynecological (gyn) applicators developed by Dr. Gilbert H. Fletcher, a radiation oncologist and chairperson from 1948 to 1981 of the department at the M.D. Anderson Hospital (MDAH) for Cancer Research in Houston, TX, and to acknowledge the previously unrecognized contribution that Dr. Leonard G. Grimmett, a radiation physicist and chairperson from 1949 to 1951 of the physics department at MDAH, made to the development of the gynecological applicators. Methods and Materials: We reviewed archival materials from the Historical Resource Center and from the Department of Radiation Physics at University of Texas M. D. Anderson Cancer Center, as well as contemporary published papers, to trace the history of the applicators. Conclusions: Dr. Fletcher's work was influenced by the work on gynecologic applicators in the 1940s in Europe, especially work done at the Royal Cancer Hospital in London. Those efforts influenced not only Dr. Fletcher's approach to the design of the applicators but also the methods used to perform in vivo measurements and determine the dose distribution. Much of the initial development of the dosimetry techniques and measurements at MDAH were carried out by Dr. Grimmett.

  8. Nailing the coffin shut on doubts that violent video games stimulate aggression: comment on Anderson et al. (2010).

    PubMed

    Huesmann, L Rowell

    2010-03-01

    Over the past half century the mass media, including video games, have become important socializers of children. Observational learning theory has evolved into social-cognitive information processing models that explain that what a child observes in any venue has both short-term and long-term influences on the child's behaviors and cognitions. C. A. Anderson et al.'s (2010) extensive meta-analysis of the effects of violent video games confirms what these theories predict and what prior research about other violent mass media has found: that violent video games stimulate aggression in the players in the short run and increase the risk for aggressive behaviors by the players later in life. The effects occur for males and females and for children growing up in Eastern or Western cultures. The effects are strongest for the best studies. Contrary to some critics' assertions, the meta-analysis of C. A. Anderson et al. is methodologically sound and comprehensive. Yet the results of meta-analyses are unlikely to change the critics' views or the public's perception that the issue is undecided because some studies have yielded null effects, because many people are concerned that the implications of the research threaten freedom of expression, and because many people have their identities or self-interests closely tied to violent video games.

  9. Preliminary report on coal resources of the Wyodak-Anderson coal zone, Powder River Basin, Wyoming and Montana

    USGS Publications Warehouse

    Ellis, Margaret S.; Gunther, Gregory L.; Flores, Romeo M.; Ochs, Allen M.; Stricker, Gary D.; Roberts, Steven B.; Taber, Thomas T.; Bader, Lisa R.; Schuenemeyer, John H.

    1998-01-01

    The National Coal Resource Assessment (NCRA) project by the U.S. Geological Survey is designed to assess US coal with the greatest potential for development in the next 20 to 30 years. Coal in the Wyodak-Anderson (WA) coal zone in the Powder River Basin of Wyoming and Montana is plentiful, clean, and compliant with EPA emissions standards. This coal is considered to be very desirable for development for use in electric power generation. The purpose of this NCRA study was to compile all available data relating to the Wyodak- Anderson coal, correlate the beds that make up the WA coal zone, create digital files pertaining to the study area and the WA coal, and produce a variety of reports on various aspects of the assessed coal unit. This report contains preliminary calculations of coal resources for the WA coal zone and is one of many products of the NCRA study. Coal resource calculations in this report were produced using both public and confidential data from many sources. The data was manipulated using a variety of commercially available software programs and several custom programs. A general description of the steps involved in producing the resource calculations is described in this report.

  10. Variational theory of valence fluctuations: Ground states and quasiparticle excitations of the Anderson lattice model

    NASA Astrophysics Data System (ADS)

    Brandow, B. H.

    1986-01-01

    A variational study of ground states of the orbitally nondegenerate Anderson lattice model, using a wave function with one variational parameter per Bloch state k, has been extended to deal with essentially metallic systems having a nonintegral number of electrons per site. Quasiparticle excitations are obtained by direct appeal to Landau's original definition for interacting Fermi liquids, scrEqp(k,σ)=δEtotal/δn qp(k,σ). This approach provides a simple and explicit realization of the Luttinger picture of a periodic Fermi liquid. A close correspondence is maintained between the ``interacting'' (U=∞) system and the corresponding ``noninteracting'' (U=0) case, i.e., ordinary band theory; the result can be described as a renormalized band or renormalized hybridization theory. The occupation-number distribution for the conduction orbitals displays a finite discontinuity at the Fermi surface. If the d-f hybridization is nonzero throughout the Brillouin zone, the quasiparticle spectrum will always exhibit a gap, although this gap becomes exponentially small (i.e., of order TK) in the Kondo-lattice regime. In the ``ionic'' case with precisely two electrons per site, such a system may therefore exhibit an insulating (semiconducting) gap. The quasiparticle state density exhibits a prominent spike on each side of the spectral gap, just as in the elementary hybridization model (the U=0 case). For the metallic case, with a nonintegral number of electrons per site, the Fermi level falls within one of the two sharp density peaks. The effective mass at the Fermi surface tends to be very large; enhancements by a factor >~102 are quite feasible. The foregoing variational theory has also been refined by means of a trial wave function having two variational parameters per Bloch state k. The above qualitative features are all retained, with some quantitative differences, but there are also some qualitatively new features. The most interesting of these is the appearance, within

  11. Menu Cycles.

    ERIC Educational Resources Information Center

    Clayton, Alfred; Almony, John

    The curriculum guide for commercial foods instruction is designed to aid the teacher in communicating the importance of menu cycles in commercial food production. It also provides information about the necessary steps in getting food from the raw form to the finished product, and then to the consumer. In addition to providing information on how to…

  12. Level repulsion exponent β for many-body localization transitions and for Anderson localization transitions via Dyson Brownian motion

    NASA Astrophysics Data System (ADS)

    Monthus, Cécile

    2016-03-01

    The generalization of the Dyson Brownian motion approach of random matrices to Anderson localization (AL) models (Chalker et al 1996 Phys. Rev. Lett. 77 554) and to many-body localization (MBL) Hamiltonians (Serbyn and Moore 2015 arXiv:1508.07293) is revisited to extract the level repulsion exponent β, where β =1 in the delocalized phase governed by the Wigner-Dyson statistics, β =0 , in the localized phase governed by the Poisson statistics, and 0<{βc}<1 at the critical point. The idea is that the Gaussian disorder variables h i are promoted to Gaussian stationary processes h i (t) in order to sample the disorder stationary distribution with some time correlation τ. The statistics of energy levels can then be studied via Langevin and Fokker-Planck equations. For the MBL quantum spin Hamiltonian with random fields h i , we obtain β =2qn,n+1\\text{EA}(N)/qn,n\\text{EA}(N) in terms of the Edwards-Anderson matrix qnm\\text{EA}(N)\\equiv \\frac{1}{N}{\\sum}i=1N|< {φn}|σ iz|{φm}> {{|}2} for the same eigenstate m  =  n and for consecutive eigenstates m  =  n  +  1. For the Anderson localization tight-binding Hamiltonian with random on-site energies h i , we find β =2{{Y}n,n+1}(N)/≤ft({{Y}n,n}(N)-{{Y}n,n+1}(N)\\right) in terms of the density correlation matrix {{Y}nm}(N)\\equiv {\\sum}i=1N|< {φn}|i> {{|}2}|< i|{φm}> {{|}2} for consecutive eigenstates m  =  n  +  1, while the diagonal element m  =  n corresponds to the inverse participation ratio {{Y}nn}(N)\\equiv {\\sum}i=1N|< {φn}|i> {{|}4} of the eigenstate |{φn}> .

  13. Current concepts in the treatment of Anderson Type II odontoid fractures in the elderly in Germany, Austria and Switzerland.

    PubMed

    Löhrer, L; Raschke, M J; Thiesen, D; Hartensuer, R; Surke, C; Ochman, S; Vordemvenne, T

    2012-04-01

    Although currently there are many different recommendations and strategies in the therapy of odontoid fractures in the elderly, there are still no generally accepted guidelines for a structured and standardised treatment. Moreover, the current opinion of spine surgeons regarding the optimal treatment of odontoid fractures Type II of the elderly is unknown. In order to have an objective insight into the diverging strategies for the management of Anderson Type II odontoid fractures and form a basis for future comparisons, this study investigated the current concepts and preferences of orthopaedic, neuro- and trauma surgeons. Spine surgeons from 34 medical schools and 8 hospitals in Germany, 4 university hospitals in Austria and 5 in Switzerland were invited to participate in an online survey using a 12-item 1-sided questionnaire. A total of 44 interviewees from 34 medical institutions participated in the survey, consisting of trauma (50%), orthopaedic (20.5%) and neurosurgeons (27.3%). Out of these, 70.5% treated 1-20 fractures per year; 63.6% favoured the anterior screw fixation as therapy for Type II odontoid fractures, the open posterior Magerl transarticular C1/C2 fusion, the posterior Harms C1/C2 fusion, and conservative immobilisation by cervical orthosis was preferred by 9.1% in each case. 59.1% preferred the anterior odontoid screw fixation as an appropriate treatment of Anderson Type II odontoid fractures in the elderly. 79.5% chose cervical orthosis for postsurgical treatment. Following operative treatment, nonunion rates were reported to be <10% and <20% by 40.9% and 70% of the surgeons, respectively. 56.8% reported changing from primary conservative to secondary operative treatment in <10% of cases. The most favoured technique in revision surgery of nonunions was the open posterior Magerl transarticular fusion technique, chosen by 38.6% of respondents. 18.2% preferred the posterior Harms C1/C2 fusion technique, 11.4% the percutaneous posterior Magerl

  14. Giant Fluctuations of Local Magnetoresistance of Organic Spin Valves and the Non-Hermitian 1D Anderson Model

    NASA Astrophysics Data System (ADS)

    Roundy, R. C.; Nemirovsky, D.; Kagalovsky, V.; Raikh, M. E.

    2014-06-01

    Motivated by recent experiments, where the tunnel magnetoresitance (TMR) of a spin valve was measured locally, we theoretically study the distribution of TMR along the surface of magnetized electrodes. We show that, even in the absence of interfacial effects (like hybridization due to donor and acceptor molecules), this distribution is very broad, and the portion of area with negative TMR is appreciable even if on average the TMR is positive. The origin of the local sign reversal is quantum interference of subsequent spin-rotation amplitudes in the course of incoherent transport of carriers between the source and the drain. We find the distribution of local TMR exactly by drawing upon formal similarity between evolution of spinors in time and of the reflection coefficient along a 1D chain in the Anderson model. The results obtained are confirmed by the numerical simulations.

  15. Studies on Valence Fluctuation and Orbital Occupancy in an Impurity Anderson Model with f2 Local-Singlet Ground State

    NASA Astrophysics Data System (ADS)

    Shiina, Ryousuke

    2017-03-01

    An interplay of valence fluctuation and orbital occupancy is studied for a two-orbital impurity Anderson model having f2 singlet ground and triplet excited states in the localized limit. Employing the numerical renormalization group method, we identify the existence of a quantum phase transition between the local-singlet and the Kondo-singlet states in a variation of the c-f hybridization, and clarify how it depends on the f2 singlet-triplet energy splitting. It is found that the transition takes place definitely at a finite strength of the hybridization even when the singlet-triplet splitting is infinitely large. It is also found that as the splitting becomes small, the occupancies of the singlet and triplet states display a drastic change in the vicinity of the transition point. The origin of these findings is discussed in view of the features of valence fluctuation from the local many-body singlet state.

  16. Price-Anderson Amendments Act of 1986. House of Representatives, Ninety-Ninth Congress, Second Session. August 5, 1986

    SciTech Connect

    Not Available

    1986-01-01

    The committee recommends several amendments to H.R. 3653, a bill designed to improve nuclear insurance procedures. Among the amendments are the inclusion of storage, handling, transportation, treatment, or disposal of, or research and development on and changes dealing with reimbursement procedures and limits. The bill reauthorizes the Price-Anderson Act, but limits liability and creates industry-wide liability in the event of a major accident. The report covers background information and hearings, summarizes the 15 amendments and each section how the bill will effect relevant changes in the Atomic Energy Act of 1954. Dissenting views argue against setting a liability cap on nuclear waste accidents because it discourages safety consciousness on the part of contractors and because there is no precedent in liability insurance for limiting liability.

  17. Effective cluster typical medium theory for the diagonal Anderson disorder model in one- and two-dimensions.

    PubMed

    Ekuma, Chinedu E; Terletska, Hanna; Meng, Zi Yang; Moreno, Juana; Jarrell, Mark; Mahmoudian, Samiyeh; Dobrosavljević, Vladimir

    2014-07-09

    We develop a cluster typical medium theory to study localization in disordered electronic systems. Our formalism is able to incorporate non-local correlations beyond the local typical medium theory in a systematic way. The cluster typical medium theory utilizes the momentum-resolved typical density of states and hybridization function to characterize the localization transition. We apply the formalism to the Anderson model of localization in one- and two-dimensions. In one-dimension, we find that the critical disorder strength scales inversely with the linear cluster size with a power law, Wc ∼ (1/Lc)(1/ν), whereas in two-dimensions, the critical disorder strength decreases logarithmically with the linear cluster size. Our results are consistent with previous numerical work and are in agreement with the one-parameter scaling theory.

  18. Effective cluster typical medium theory for the diagonal Anderson disorder model in one- and two-dimensions

    NASA Astrophysics Data System (ADS)

    Ekuma, Chinedu E.; Terletska, Hanna; Meng, Zi Yang; Moreno, Juana; Jarrell, Mark; Mahmoudian, Samiyeh; Dobrosavljević, Vladimir

    2014-07-01

    We develop a cluster typical medium theory to study localization in disordered electronic systems. Our formalism is able to incorporate non-local correlations beyond the local typical medium theory in a systematic way. The cluster typical medium theory utilizes the momentum-resolved typical density of states and hybridization function to characterize the localization transition. We apply the formalism to the Anderson model of localization in one- and two-dimensions. In one-dimension, we find that the critical disorder strength scales inversely with the linear cluster size with a power law, Wc ˜ (1/Lc)1/ν, whereas in two-dimensions, the critical disorder strength decreases logarithmically with the linear cluster size. Our results are consistent with previous numerical work and are in agreement with the one-parameter scaling theory.

  19. Scaling analysis of domain-wall free energy in the Edwards-Anderson Ising spin glass in a magnetic field.

    PubMed

    Sasaki, M; Hukushima, K; Yoshino, H; Takayama, H

    2007-09-28

    The stability of the spin-glass phase against a magnetic field is studied in the three- and four-dimensional Edwards-Anderson Ising spin glasses. Effective couplings J(eff) and effective fields H(eff) associated with length scale L are measured by a numerical domain-wall renormalization-group method. The results obtained by scaling analysis of the data strongly indicate the existence of a crossover length beyond which the spin-glass order is destroyed by field H. The crossover length well obeys a power law of H which diverges as H --> 0 but remains finite for any nonzero H, implying that the spin-glass phase is absent even in an infinitesimal field. These results are well consistent with the droplet theory for short-range spin glasses.

  20. Review of Immune-Related Adverse Events in Prostate Cancer Patients Treated with Ipilimumab: MD Anderson Experience

    PubMed Central

    Gao, Jianjun; He, Qiuming; Subudhi, Sumit; Aparicio, Ana; Zurita-Saavedra, Amado; Lee, Da Hyun; Jimenez, Camilo; Suarez-Almazor, Maria; Sharma, Padmanee

    2014-01-01

    Targeting a T cell inhibitory checkpoint with the anti-CTLA-4 monoclonal antibody, ipilimumab, represents a scientific breakthrough in immunotherapy for the treatment of cancer. However, ipilimumab therapy is also associated with unique side effects, known as immune-related adverse events (irAEs), which need to be recognized and managed with immunosuppressive agents. To date, the majority of our knowledge regarding ipilimumab-associated side effects is based upon clinical studies in melanoma. Here, we provide a review of ipilimumab-induced irAEs and our experience in a cohort of 44 patients with prostate cancer who were treated at M. D. Anderson Cancer Center on two different clinical trial protocols. PMID:25659583

  1. GW approach to electron-electron interactions within the Anderson impurity model: Kondo correlated quantum transport through two coupled molecules

    NASA Astrophysics Data System (ADS)

    Aksu, H.; Goker, A.

    2017-03-01

    We invoke the nonequilibrium self-consistent GW method within the Anderson impurity model to investigate the dynamical effects occurring in a nanojunction comprised of two coupled molecules. Contrary to the previous single impurity model calculations based on the GW approximation, we observe that the density of states manages to capture both the Kondo resonance and the Breit-Wigner resonances associated with the HOMO and LUMO levels of the molecule. Moreover, the prominence of the Kondo resonance grows dramatically upon switching from the intermediate to the weak coupling regime involving large U / Γ values. The conductance is calculated as a function of the HOMO level and the applied bias across the molecular nanojunction. Calculated conductance curves deviate from the monotonic decay behaviour as a function of the bias when the half-filling condition is not met. The importance of the effect of the molecule-molecule coupling for the electron transport phenomena is also investigated.

  2. [Long-term follow up of patients surgically treated for pyelo-ureteral disease by the Anderson-Hynes technique].

    PubMed

    Polito, M; Galosi, A B; Minardi, D; Nonni, M; Cinti, P; Riccardi, A

    1997-02-01

    A series of 48 patients with hydronephrosis (mean age 31 yrs.) underwent on Anderson-Hynes pyeloplasty. Assessment was carried out in 30 pts. after a mean observation time of 90 months, with a minimum 5 years follow-up. Clinical examination, laboratory investigations, renal ultrasonography, urography and renal scan were performed pre-operatively and at follow-up. There was one patient with evidence of stenosis in the ureteropelvic junction; one patient developed urinary leakage post-operatively and required surgical correction. All patients had symptoms pre-operatively and no one had symptoms post-operatively. Four patients had calcolosis associated, postoperatively all pts. were stone free; four years later one patient developed litiasis. We observed that the results of surgical intervention in hydronephrosis are excellent especially in patients aged less than 30 years.

  3. Observation of the Quantum Anomalous Hall Insulator to Anderson Insulator Quantum Phase Transition and its Scaling Behavior

    NASA Astrophysics Data System (ADS)

    Chang, Cui-Zu; Zhao, Weiwei; Li, Jian; Jain, J. K.; Liu, Chaoxing; Moodera, Jagadeesh S.; Chan, Moses H. W.

    2016-09-01

    Fundamental insight into the nature of the quantum phase transition from a superconductor to an insulator in two dimensions, or from one plateau to the next or to an insulator in the quantum Hall effect, has been revealed through the study of its scaling behavior. Here, we report on the experimental observation of a quantum phase transition from a quantum-anomalous-Hall insulator to an Anderson insulator in a magnetic topological insulator by tuning the chemical potential. Our experiment demonstrates the existence of scaling behavior from which we extract the critical exponent for this quantum phase transition. We expect that our work will motivate much further investigation of many properties of quantum phase transition in this new context.

  4. Observation of the Quantum Anomalous Hall Insulator to Anderson Insulator Quantum Phase Transition and its Scaling Behavior.

    PubMed

    Chang, Cui-Zu; Zhao, Weiwei; Li, Jian; Jain, J K; Liu, Chaoxing; Moodera, Jagadeesh S; Chan, Moses H W

    2016-09-16

    Fundamental insight into the nature of the quantum phase transition from a superconductor to an insulator in two dimensions, or from one plateau to the next or to an insulator in the quantum Hall effect, has been revealed through the study of its scaling behavior. Here, we report on the experimental observation of a quantum phase transition from a quantum-anomalous-Hall insulator to an Anderson insulator in a magnetic topological insulator by tuning the chemical potential. Our experiment demonstrates the existence of scaling behavior from which we extract the critical exponent for this quantum phase transition. We expect that our work will motivate much further investigation of many properties of quantum phase transition in this new context.

  5. Insertion-release of guest species and ionic conduction in polyoxometalate solids with a layer-like Anderson structure

    SciTech Connect

    Naruke, Haruo; Kajitani, Naoyuki; Konya, Takayuki

    2011-04-15

    The precipitation of Na{sup +} and K{sup +} mixed salts of Anderson type [SbW{sub 6}O{sub 24}]{sup 7-} by addition of excess of NaNO{sub 3} and NaCl yielded polycrystalline powders of Na{sub 2.5}K{sub 5.3}[SbW{sub 6}O{sub 24}](NO{sub 3}){sub 0.8}.12H{sub 2}O (1) and Na{sub 2}K{sub 5.35}[SbW{sub 6}O{sub 24}]Cl{sub 0.35}.12H{sub 2}O (2), respectively. The two compounds are isomorphous and exhibit a layer-like Anderson (LLA) type structure, which consists of [SbW{sub 6}O{sub 24}]{sup 7-}-containing layers and interstitial Na{sup +}, K{sup +}, NO{sub 3}{sup -} or Cl{sup -}, and water O atoms. Recrystallization of 1 and 2 from hot water yielded Na{sub 2}K{sub 5.4}[SbW{sub 6}O{sub 24}](NO{sub 3}){sub 0.4}.12H{sub 2}O (1-recry) and Na{sub 2}K{sub 5.25}[SbW{sub 6}O{sub 24}]Cl{sub 0.25}.12H{sub 2}O (2-recry) as a result of partial release of NO{sub 3}{sup -} and Cl{sup -} (and Na{sup +} and K{sup +} for charge compensation). Dehydration of 1 and 2 at 400 and 500 {sup o}C (1-dehyd400 and 2-dehyd500) caused a shrinkage of lattice, but their the LLA structures retained. Simulation of X-ray diffraction (XRD) patterns for the dehydrated forms allowed to presume that the each [SbW{sub 6}O{sub 24}]{sup 7-} anion had been 30{sup o}-rotated within its molecular plane in order to avoid intermolecular repulsion. A compressed powder of 1-dehyd400 exhibited fast alkaline-ion conduction with a bulk conductivity of 1.2x10{sup -2} {Omega}{sup -1} cm{sup -1} at 400 {sup o}C. The hosting of a sufficient amount of NO{sub 3}{sup -} together with Na{sup +} for charge compensation into the lattice is crucial for high conduction. -- Graphical abstract: Two compounds Na{sub 2.5}K{sub 5.3}[SbW{sub 6}O{sub 24}](NO{sub 3}){sub 0.8}.12H{sub 2}O (1) and Na{sub 2}K{sub 5.35}[SbW{sub 6}O{sub 24}]Cl{sub 0.35}.12H{sub 2}O (2) possessing a layer-like Anderson (LLA) structure exhibited pseudo intercalation-deintercalation behavior. The dehydrated form of 1 is a high alkaline cation conductor with a

  6. A Central Limit Theorem for Products of Random Matrices and GOE Statistics for the Anderson Model on Long Boxes

    NASA Astrophysics Data System (ADS)

    Sadel, Christian; Virág, Bálint

    2016-05-01

    We consider products of random matrices that are small, independent identically distributed perturbations of a fixed matrix T_0. Focusing on the eigenvalues of T_0 of a particular size we obtain a limit to a SDE in a critical scaling. Previous results required T_0 to be a (conjugated) unitary matrix so it could not have eigenvalues of different modulus. From the result we can also obtain a limit SDE for the Markov process given by the action of the random products on the flag manifold. Applying the result to random Schrödinger operators we can improve some results by Valko and Virag showing GOE statistics for the rescaled eigenvalue process of a sequence of Anderson models on long boxes. In particular, we solve a problem posed in their work.

  7. Non-Fermi Liquid Behavior and Continuously Tunable Resistivity Exponents in the Anderson-Hubbard Model at Finite Temperature

    NASA Astrophysics Data System (ADS)

    Patel, Niravkumar D.; Mukherjee, Anamitra; Kaushal, Nitin; Moreo, Adriana; Dagotto, Elbio

    2017-08-01

    We employ a recently developed computational many-body technique to study for the first time the half-filled Anderson-Hubbard model at finite temperature and arbitrary correlation U and disorder V strengths. Interestingly, the narrow zero temperature metallic range induced by disorder from the Mott insulator expands with increasing temperature in a manner resembling a quantum critical point. Our study of the resistivity temperature scaling Tα for this metal reveals non-Fermi liquid characteristics. Moreover, a continuous dependence of α on U and V from linear to nearly quadratic is observed. We argue that these exotic results arise from a systematic change with U and V of the "effective" disorder, a combination of quenched disorder and intrinsic localized spins.

  8. Kinetics of local "magnetic" moment and non-stationary spin-polarized current in the single impurity Anderson-model

    NASA Astrophysics Data System (ADS)

    Maslova, N. S.; Mantsevich, V. N.; Arseyev, P. I.

    2017-02-01

    We perform theoretical investigation of the localized state dynamics in the presence of interaction with the reservoir and Coulomb correlations. We analyze kinetic equations for electron occupation numbers with different spins taking into account high order correlation functions for the localized electrons. We reveal that in the stationary state electron occupation numbers with the opposite spins always have the same value - the stationary state is a "paramagnetic" one. "Magnetic" properties can appear only in the non-stationary characteristics of the single-impurity Anderson model and in the dynamics of the localized electrons second order correlation functions. We found, that for deep energy levels and strong Coulomb correlations, relaxation time for initial "magnetic" state can be several orders larger than for "paramagnetic" one. So, long-living "magnetic" moment can exist in the system. We also found non-stationary spin polarized currents flowing in opposite directions for the different spins in the particular time interval.

  9. Anderson-Fabry disease: clinical manifestations and impact of disease in a cohort of 98 hemizygous males

    PubMed Central

    MacDermot, K; Holmes, A; Miners, A

    2001-01-01

    OBJECTIVES—To determine the natural history of Anderson-Fabry disease (AFD) as a baseline for efficacy assessment of potentially therapeutic drugs.
DESIGN—The first large cross sectional study of a patient cohort from the AFD clinical and genetic register (UK), maintained for the last 15 years.
MEASURES—Prevalence, mortality, frequency of AFD manifestations, and impact of disease on patient lives, assessed from the AFD register and the disease specific questionnaire.
RESULTS—The median cumulative survival was 50 years (n=51), which represents an approximately 20 year reduction of life span. Neuropathic pain was present in 77% (n=93) with mean pain score of 5 (scale 0-10) despite treatment with anticonvulsants and opiates. Pain stopped in only 11%. Cerebrovascular complications developed in 24.2% and renal failure in 30%. The onset and progression of serious AFD manifestations was highly variable. The relationship of gastrointestinal manifestations on weight, using body mass index (BMI), was significant (p=0.01). High frequency sensorineural deafness was confirmed in 78% of audiograms. Neuropathic pain and angiokeratoma were absent in five adult males (~5%). Median age at diagnosis of AFD was 21.9 years (n=64).
IMPACT OF DISEASE—Attendance at school, sports, and social activity were significantly affected by AFD. Only 56.6% (n=46) of patients were employed. Psychosexual effects of genital angiokeratoma, genital pain, and impotence were not previously recognised.
CONCLUSION—The majority of males experience multiple disease manifestations and the duration of neuropathic pain was lifelong. The AFD register proved useful for the determination of baseline disease parameters in this cohort.


Keywords: Anderson-Fabry disease; natural history; mortality; prevalence PMID:11694547

  10. Anderson lattice with explicit Kondo coupling revisited: metamagnetism and the field-induced suppression of the heavy fermion state.

    PubMed

    Howczak, Olga; Spałek, Jozef

    2012-05-23

    We apply the extended (statistically consistent, SCA) Gutzwiller-type approach to the periodic Anderson model (PAM) in an applied magnetic field and in the strong-correlation limit. The finite-U corrections are included systematically by transforming the PAM into the form with the Kondo-type interaction and the residual hybridization, both appearing at the same time and on equal footing. This effective Hamiltonian represents the essence of our Anderson-Kondo lattice model. We show that in ferromagnetic phases the low-energy single-particle states are strongly affected by the presence of the applied magnetic field. We also find that for large values of hybridization strength the system enters the so-called locked heavy fermion state introduced earlier. In this state the chemical potential lies in the majority-spin hybridization gap and, as a consequence, the system evolution is insensitive to further increase of the applied field. However, for a sufficiently strong magnetic field, the system transforms from the locked state to the fully spin-polarized phase. This is accompanied by a metamagnetic transition, as well as by a drastic reduction of the effective mass of the quasiparticles. In particular, we observe no effective mass enhancement in the fully polarized state. The findings are in overall agreement with experimental results for the Ce compounds in high magnetic fields. The mass enhancement for the spin-minority electrons may also diminish with the increasing field, unlike for the quasiparticle states in a single narrow band in the same limit of strong correlations.

  11. Variable induction of vitellogenin genes in the varroa mite, Varroa destructor (Anderson & Trueman) by the honeybee, Apis mellifera L, host and its environment

    USDA-ARS?s Scientific Manuscript database

    Transcript levels of vitellogenins (Vgs) in the varroa mite, Varroa destructor (Anderson & Trueman) were variably induced by interactions between the developing honeybee as a food source and the capped honeybee cell environment. Transcripts for 2 Vgs of varroa mites were sequenced and putative Vg pr...

  12. University of Texas MD Anderson: Phenotypic Examination of PIK3CA Allelic Series using In Vitro/In Vivo Sensor Platforms | Office of Cancer Genomics

    Cancer.gov

    The CTD2 Center at the University of Texas MD Anderson Cancer Center utilized an established and operational MCF10A normal breast epithelial cell model to assess the ability of candidate driver aberrations to promote cell grow in anchorage-independent conditions (soft agar assay) and proliferate in the absence of insulin and epidermal growth factor (EGF).

  13. CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES: Parametrization of Transfer Matrix: for One-Dimensional Anderson Model with Diagonal Disorder

    NASA Astrophysics Data System (ADS)

    Kang, Kai; Qin, Shao-Jing; Wang, Chui-Lin

    2010-10-01

    In this paper, we developed a new parametrization method to calculate the localization length in one-dimensional Anderson model with diagonal disorder. This method can avoid the divergence difficulty encountered in the conventional methods, and significantly save computing time as well.

  14. Examining the role of foraging and malvolio in host-finding behavior in the honey bee parasite, Varroa destructor (Anderson & Trueman)

    USDA-ARS?s Scientific Manuscript database

    When a female varroa mite, Varroa destructor (Anderson & Trueman), invades a honey bee brood cell, the physiology rapidly changes from the feeding phoretic to reproductive. Changes in the foraging and malvolio transcript levels in the brain have been associated with modulated intra-specific food sea...

  15. Paleontological analysis of a lacustrine carbonaceous uranium deposit at the Anderson mine, Date Creek basin, west-central Arizona (U.S.A.)

    USGS Publications Warehouse

    Otton, J.K.; Bradbury, J.P.; Forester, R.M.; Hanley, J.H.

    1990-01-01

    The Tertiary sedimentary sequence of the Date Creek basin area of Arizona is composed principally of intertonguing alluvial-fan and lacustrine deposits. The lacustrine rocks contain large intermediate- to, locally, high-grade uranium deposits that form one of the largest uranium resources in the United States (an estimated 670,000 tons of U3O8 at an average grade of 0.023% is indicated by drilling to date). At the Anderson mine, about 50,000 tons of U3O8 occurs in lacustrine carbonaceous siltstones and mudstones (using a cutoff grade of 0.01%). The Anderson mine constitutes a new class of ore deposit, a lacustrine carbonaceous uranium deposit. Floral and faunal remains at the Anderson mine played a critical role in creating and documenting conditions necessary for uranium mineralization. Organic-rich, uraniferous rocks at the Anderson mine contain plant remains and ostracodes having remarkably detailed preservation of internal features because of infilling by opaline silica. This preservation suggests that the alkaline lake waters in the mine area contained high concentrations of dissolved silica and that silicification occurred rapidly, before compaction or cementation of the enclosing sediment. Uranium coprecipitated with the silica. Thinly laminated, dark-colored, siliceous beds contain centric diatoms preserved with carbonaceous material suggesting that lake waters at the mine were locally deep and anoxic. These alkaline, silica-charged waters and a stagnant, anoxic environment in parts of the lake were necessary conditions for the precipitation of large amounts of uranium in the lake-bottom sediments. Sediments at the Anderson mine contain plant remains and pollen that were derived from diverse vegetative zones suggesting about 1500 m of relief in the area at the time of deposition. The pollen suggests that the valley floor was semiarid and subtropical, whereas nearby mountains supported temperate deciduous forests. ?? 1990.

  16. Preliminary report on methodology for calculating coal resources of the Wyodak-Anderson coal zone, Powder River basin, Wyoming and Montana

    USGS Publications Warehouse

    Ellis, Margaret S.; Gunther, Gregory L.; Flores, Romeo M.; Stricker, Gary D.; Ochs, Allan M.; Schuenemeyer, John H.

    1998-01-01

    The National Coal Resource Assessment of the Wyodak-Anderson coal zone includes reports on the geology, stratigraphy, quality, and quantity of coal. The calculation of resources is only one aspect of the assessment. Without thorough documentation of the coal resource study and the methods used, the results of our study could be misinterpreted. The task of calculating coal resources included many steps, the use of several commercial software programs, and the incorporation of custom programs. The methods used for calculating coal resources for the Wyodak-Anderson coal zone vary slightly from the methods used in other study areas, and by other workers in the National Coal Resource Assessment. The Wyodak-Anderson coal zone includes up to 10 coal beds in any given location. The net coal thickness of the zone at each data point location was calculated by summing the thickness of all of the coal beds that were greater than 2.5 ft thick. The amount of interburden is not addressed or reported in this coal resource assessment. The amount of overburden reported is the amount of rock above the stratigraphically highest coal bed in the zone. The resource numbers reported do not include coal within mine or lease areas, in areas containing mapped Wyodak-Anderson clinker, or in areas where the coal is extrapolated to be less than 2.5 ft thick. The resources of the Wyodak-Anderson coal zone are reported in Ellis and others (1998). A general description of how the resources were calculated is included in that report. The purpose of this report is to document in more detail some of the parameters and methods used, define our spatial data, compare resources calculated using different grid options and calculation methods, and explain the application of confidence limits to the resource calculation.

  17. The effect of delayed host self-regulation on host-pathogen population cycles in forest insects.

    PubMed

    Xiao, Yanni; Bowers, Roger G; Tang, Sanyi

    2009-05-21

    Delayed host self-regulation using a Beverton-Holt function and delayed logistic self-regulation are included in a host-pathogen model with free-living infective stages (Anderson and May's model G) with the purpose of investigating whether adding the relatively complex self-regulations decrease the likelihood of population cycles. The main results indicate that adding delayed self-regulation to the baseline model increases the likelihood of population cycles. The dynamics display some of the key features seen in the field, such as cycle peak density exceeding the carrying capacity and a locally stable equilibrium coexisting with a stable cycle (bistability). Numerical studies show that the model with more complex forms of self-regulation can generate cycles which match most aspects of the cycles observed in nature.

  18. Effet de l'interaction coulombienne sur la localisation d'Anderson dans le gaz bidimensionnel d'électrons

    NASA Astrophysics Data System (ADS)

    Fleury, G.

    2010-09-01

    Nous étudions l’effet des interactions coulombiennes sur la localisation d’Anderson dans le gaz bidimensionnel d’électrons désordonné. L’objectif est de statuer sur la question de l’existence de métaux à deux dimensions. En l’absence d’interaction, la théorie d’échelle de la localisation prédit qu’un désordre infinitésimal suffit à localiser la fonction d’onde électronique et donc à rendre le système isolant à température nulle (Abrahams et al., 1979). Dans certaines limites extrêmes, les interactions peuvent être prises en compte et l’on aboutit également à un état isolant. Cependant, aucune théorie analytique ne permet de traiter le régime quantique non-perturbatif où désordre et interaction sont intermédiaires. Expérimentalement, il est possible de l’explorer dans des échantillons de haute mobilité et basse densité. Depuis 1994, des comportements métalliques inexpliqués y ont été observés (Kravchenko et al., 1994). Nous avons mis au point une méthode numérique permettant d’étudier le problème couplé de la localisation d’Anderson en présence d’interaction. Cette méthode mêle Monte Carlo quantique à température nulle et théorie d’échelle pour la conductance de Thouless. Nous trouvons que la théorie d’échelle de la localisation est préservée en présence d’interaction et donc que le gaz bidimensionnel, même corrélé, est isolant à température nulle. Nos résultats montrent de plus que les interactions délocalisent le gaz bidimensionnel et que cet effet de délocalisation est accru en présence de dégénérescence de vallées. Ils nous permettent de proposer un mécanisme simple rendant compte des principales caractéristiques des comportements métalliques observés expérimentalement.

  19. Bipolaron-SO(5) non-Fermi liquid in a two-channel Anderson model with phonon-assisted hybridizations

    NASA Astrophysics Data System (ADS)

    Hattori, K.

    2012-06-01

    We analyze non-Fermi liquid (NFL) properties along a line of critical points in a two-channel Anderson model with phonon-assisted hybridizations. We succeed in identifying hidden nonmagnetic SO(5) degrees of freedom for the valence-fluctuation regime, and we analyze the model on the basis of boundary conformal field theory. We find that the NFL spectra along the critical line, which is the same as those in the two-channel Kondo model, can be alternatively derived by a fusion in the nonmagnetic SO(5) sector. The leading irrelevant operators near the NFL fixed points vary as a function of Coulomb repulsion U; operators in the spin sector dominate for large U, while those in the SO(5) sector dominate for small U, and we confirm this variation in our numerical renormalization group calculations. As a result, the thermodynamic singularity for small U differs from that of the conventional two-channel Kondo problem. In particular, the impurity contribution to specific heat is proportional to temperature, and bipolaron fluctuations, which are coupled electron-phonon fluctuations, diverge logarithmically at low temperatures for small U.

  20. Renormalization group flow of the Luttinger-Ward functional: Conserving approximations and application to the Anderson impurity model

    NASA Astrophysics Data System (ADS)

    Rentrop, J. F.; Meden, V.; Jakobs, S. G.

    2016-05-01

    We study the renormalization group flow of the Luttinger-Ward functional and of its two-particle-irreducible vertex functions, given a cutoff in the two-particle interaction. We derive a conserving approximation to the flow and relate it to the fluctuation exchange approximation as well as to nonconserving approximations introduced in an earlier publication [J. F. Rentrop, S. G. Jakobs, and V. Meden, J. Phys. A: Math. Theor. 48, 145002 (2015), 10.1088/1751-8113/48/14/145002]. We apply the different approximate flow equations to the single-impurity Anderson model in thermal equilibrium at vanishing temperature. Numerical results for the effective mass, the spin susceptibility, the charge susceptibility, and the linear conductance reflect the similarity of the methods to the fluctuation exchange approximation. We find the majority of the approximations to deviate stronger from the exact results than one-particle-irreducible functional renormalization group schemes. However, we identify a simple static two-particle-irreducible flow scheme which performs remarkably well and produces an exponential Kondo-like scale in the renormalized level position.

  1. Anderson's disease (chylomicron retention disease): a new mutation in the SARA2 gene associated with muscular and cardiac abnormalities.

    PubMed

    Silvain, M; Bligny, D; Aparicio, T; Laforêt, P; Grodet, A; Peretti, N; Ménard, D; Djouadi, F; Jardel, C; Bégué, J M; Walker, F; Schmitz, J; Lachaux, A; Aggerbeck, L P; Samson-Bouma, M E

    2008-12-01

    Anderson's disease (AD) or chylomicron retention disease (CMRD) is a rare hereditary lipid malabsorption syndrome linked to SARA2 gene mutations. We report in this study a novel mutation in two sisters for which the Sar1b protein is predicted to be truncated by 32 amino acids at its carboxyl-terminus. Because the SARA2 gene is also expressed in the muscle, heart, liver and placenta, extraintestinal clinical manifestations may exist. For the first time, we describe in this study in the two sisters muscular as well as cardiac abnormalities that could be related to the reported expression of SARA2 in these tissues. We also evaluated six other patients for potential manifestations of the SARA2 mutation. The creatine phosphokinase levels were increased in all patients [1.5-9.4 x normal (N)] and transaminases were moderately elevated in five of the eight patients (1.2-2.6 x N), probably related to muscle disease rather than to liver dysfunction. A decreased ejection fraction occurred in one patient (40%, N: 60%). The muscle, liver and placental tissues that were examined had no specific abnormalities and, in particular, no lipid accumulation. These results suggest that myolysis and other extraintestinal abnormalities can occur in AD/CMRD and that the clinical evaluation of patients should reflect this.

  2. Transient phases and dynamical transitions in the post-quench evolution of the generalized Bose-Anderson model

    NASA Astrophysics Data System (ADS)

    Chichinadze, Dmitry V.; Ribeiro, Pedro; Shchadilova, Yulia E.; Rubtsov, Alexey N.

    2016-08-01

    The exact description of the time evolution of open correlated quantum systems remains one of the major challenges of condensed matter theory, especially for asymptotic long times where most numerical methods fail. Here, the post-quench dynamics of the N -component Bose-Anderson impurity model is studied in the N →∞ limit. The equilibrium phase diagram is similar to that of the Bose-Hubbard model in that it contains local versions of Mott and Bose phases. Using a numerically exact procedure, we are able to study the real-time evolution including asymptotic long-time regimes. The formation of long-lived transient phases is observed for quench paths crossing foreign phases. For quenches inside the local Bose condensed phase, a dynamical phase transition is reported that separates the evolution towards a new equilibrium state and a regime characterized at large times by a persistent phase rotation of the order parameter. We explain how such nondecaying modes can exist in the presence of a dissipative bath. We discuss the extension of our results to the experimental relevant finite-N case and their implication for the existence of nondecaying modes in generic quantum systems in the presence of a bath.

  3. Parallel tempering simulation of the three-dimensional Edwards-Anderson model with compact asynchronous multispin coding on GPU

    NASA Astrophysics Data System (ADS)

    Fang, Ye; Feng, Sheng; Tam, Ka-Ming; Yun, Zhifeng; Moreno, Juana; Ramanujam, J.; Jarrell, Mark

    2014-10-01

    Monte Carlo simulations of the Ising model play an important role in the field of computational statistical physics, and they have revealed many properties of the model over the past few decades. However, the effect of frustration due to random disorder, in particular the possible spin glass phase, remains a crucial but poorly understood problem. One of the obstacles in the Monte Carlo simulation of random frustrated systems is their long relaxation time making an efficient parallel implementation on state-of-the-art computation platforms highly desirable. The Graphics Processing Unit (GPU) is such a platform that provides an opportunity to significantly enhance the computational performance and thus gain new insight into this problem. In this paper, we present optimization and tuning approaches for the CUDA implementation of the spin glass simulation on GPUs. We discuss the integration of various design alternatives, such as GPU kernel construction with minimal communication, memory tiling, and look-up tables. We present a binary data format, Compact Asynchronous Multispin Coding (CAMSC), which provides an additional 28.4% speedup compared with the traditionally used Asynchronous Multispin Coding (AMSC). Our overall design sustains a performance of 33.5 ps per spin flip attempt for simulating the three-dimensional Edwards-Anderson model with parallel tempering, which significantly improves the performance over existing GPU implementations.

  4. No correlation between Anderson Reservoir stage level and underlying Calaveras fault seismicity despite calculated differential stress increases

    USGS Publications Warehouse

    Parsons, T.

    2011-01-01

    Concerns have been raised that stresses from reservoir impoundment may trigger damaging earthquakes because rate changes have been associated with reservoir impoundment or stage-level changes globally. Here, the idea is tested blindly using Anderson Reservoir, which lies atop the seismically active Calaveras fault. The only knowledge held by the author going into the study was the expectation that reservoir levels change cyclically because of seasonal rainfall. Examination of seismicity rates near the reservoir reveals variability, but no correlation with stage-level changes. Three-dimensional fi nite-element modeling shows stress changes suffi cient for earthquake triggering along the Calaveras fault zone. Since many of the reported cases of induced triggering come from low-strain settings, it is speculated that gradual stressing from stage-level changes in high-strain settings may not be signifi cant. From this study, it can be concluded that reservoirs are not necessarily risky in active tectonic settings. ?? 2011 Geological Society of America.

  5. Effects of an additional conduction band on the singlet-antiferromagnet competition in the periodic Anderson model

    DOE PAGES

    Hu, Wenjian; Scalettar, Richard T.; Huang, Edwin W.; ...

    2017-06-12

    The competition between antiferromagnetic (AF) order and singlet formation is a central phenomenon of the Kondo and periodic Anderson Hamiltonians and of the heavy fermion materials they describe. In this paper, we explore the effects of an additional conduction band on magnetism in these models, and, specifically, on changes in the AF-singlet quantum critical point (QCP) and the one particle and spin spectral functions. To understand the magnetic phase transition qualitatively, we first carry out a self-consistent mean field theory (MFT). The basic conclusion is that, at half filling, the coupling to the additional band stabilizes the AF phase tomore » larger f d hybridization V in the PAM. We also explore the possibility of competing ferromagnetic phases when this conduction band is doped away from half filling. Here, we next employ quantum Monte Carlo (QMC) which, in combination with finite size scaling, allows us to evaluate the position of the QCP using an exact treatment of the interactions. This approach confirms the stabilization of AF order, which occurs through an enhancement of the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction. QMC results for the spectral function A (q,ω) and dynamic spin structure factor χ (q,ω) yield additional insight into the AF-singlet competition and the low temperature phases.« less

  6. A Functional Generalization of the Field-Theoretical Renormalization Group Approach for the Single-Impurity Anderson Model

    NASA Astrophysics Data System (ADS)

    Freire, Hermann; Corrêa, Eberth

    2012-02-01

    We apply a functional implementation of the field-theoretical renormalization group (RG) method up to two loops to the single-impurity Anderson model. To achieve this, we follow a RG strategy similar to that proposed by Vojta et al. (in Phys. Rev. Lett. 85:4940, 2000), which consists of defining a soft ultraviolet regulator in the space of Matsubara frequencies for the renormalized Green's function. Then we proceed to derive analytically and solve numerically integro-differential flow equations for the effective couplings and the quasiparticle weight of the present model, which fully treat the interplay of particle-particle and particle-hole parquet diagrams and the effect of the two-loop self-energy feedback into them. We show that our results correctly reproduce accurate numerical renormalization group data for weak to slightly moderate interactions. These results are in excellent agreement with other functional Wilsonian RG works available in the literature. Since the field-theoretical RG method turns out to be easier to implement at higher loops than the Wilsonian approach, higher-order calculations within the present approach could improve further the results for this model at stronger couplings. We argue that the present RG scheme could thus offer a possible alternative to other functional RG methods to describe electronic correlations within this model.

  7. Spin-current Seebeck effect in an interacting quantum dot: Atomic approximation for the Anderson impurity model

    NASA Astrophysics Data System (ADS)

    Ramos, E.; Silva-Valencia, J.; Franco, R.; Siqueira, E. C.; Figueira, M. S.

    2015-11-01

    We study the spin-current Seebeck effect through an immersed gate defined quantum dot, employing the U-finite atomic method for the single impurity Anderson model. Our description qualitatively confirms some of the results obtained by an earlier Hartree-Fock work, but as our calculation includes the Kondo effect, some new features will appear in the spin-current Seebeck effect S, which as a function of the gate voltage present an oscillatory shape. At intermediate temperatures, our results show a three zero structure and at low temperatures, our results are governed by the emergence of the Kondo peak in the transmittance, which defines the behavior of the shape of the S coefficient as a function of the parameters of the model. The oscillatory behavior obtained by the Hartree-Fock approximation reproduces the shape obtained by us in a non-interacting system (U=0). The S sign is sensitive to different polarization of the quantum dot, and as a consequence the device could be employed to experimentally detect the polarization states of the system. Our results also confirm that the large increase of S upon increasing U, obtained by the mean field approximation, is correct only for low temperatures. We also discuss the role of the Kondo peak in defining the behavior of the spin thermopower at low temperatures.

  8. Quantum critical scaling for field-induced quantum phase transition in a periodic Anderson-like model polymer chain

    NASA Astrophysics Data System (ADS)

    Ding, L. J.; Zhong, Y.

    2017-07-01

    The quantum phase transition and thermodynamics of a periodic Anderson-like polymer chain in a magnetic field are investigated by Green's function theory. The T-h phase diagram is explored, wherein a crossover temperature T∗ denoting the gapless phase crossover into quantum critical regimes, smoothly connects near the critical fields to the universal linear line T∗ ∼ (h - hc,s), and ends at hc,s, providing a new route to capture quantum critical point (QCP). The quantum critical scaling around QCPs is demonstrated by analyzing magnetization, specific heat and Grüneisen parameter Γh, which provide direct access to distill the power-law critical exponents (β, δ and α) obeying the critical scaling relation α + β(1 + δ) = 2, analogous to the quantum spin system. Furthermore, scaling hypothesis equations are proposed to check the scaling analysis, for which all the data collapse onto a single curve or two independent branches for the plot against an appropriate scaling variable, indicating the self-consistency and reliability of the obtained critical exponents.

  9. Surface hopping with a manifold of electronic states. II. Application to the many-body Anderson-Holstein model

    SciTech Connect

    Dou, Wenjie; Subotnik, Joseph E.; Nitzan, Abraham

    2015-02-28

    We investigate a simple surface hopping (SH) approach for modeling a single impurity level coupled to a single phonon and an electronic (metal) bath (i.e., the Anderson-Holstein model). The phonon degree of freedom is treated classically with motion along–and hops between–diabatic potential energy surfaces. The hopping rate is determined by the dynamics of the electronic bath (which are treated implicitly). For the case of one electronic bath, in the limit of small coupling to the bath, SH recovers phonon relaxation to thermal equilibrium and yields the correct impurity electron population (as compared with numerical renormalization group). For the case of out of equilibrium dynamics, SH current-voltage (I-V) curve is compared with the quantum master equation (QME) over a range of parameters, spanning the quantum region to the classical region. In the limit of large temperature, SH and QME agree. Furthermore, we can show that, in the limit of low temperature, the QME agrees with real-time path integral calculations. As such, the simple procedure described here should be useful in many other contexts.

  10. Microwave conductance in random waveguides in the cross-over to Anderson localization and single-parameter scaling

    PubMed Central

    Shi, Zhou; Wang, Jing; Genack, Azriel Z.

    2014-01-01

    The nature of transport of electrons and classical waves in disordered systems depends upon the proximity to the Anderson localization transition between freely diffusing and localized waves. The suppression of average transport and the enhancement of relative fluctuations in conductance in one-dimensional samples with lengths greatly exceeding the localization length, , are related in the single-parameter scaling (SPS) theory of localization. However, the difficulty of producing an ensemble of statistically equivalent samples in which the electron wave function is temporally coherent has so-far precluded the experimental demonstration of SPS. Here we demonstrate SPS in random multichannel systems for the transmittance T of microwave radiation, which is the analog of the dimensionless conductance. We show that for , a single eigenvalue of the transmission matrix (TM) dominates transmission, and the distribution of the is Gaussian with a variance equal to the average of , as conjectured by SPS. For samples in the cross-over to localization, , we find a one-sided distribution for . This anomalous distribution is explained in terms of a charge model for the eigenvalues of the TM τ in which the Coulomb interaction between charges mimics the repulsion between the eigenvalues of TM. We show in the localization limit that the joint distribution of T and the effective number of transmission eigenvalues determines the probability distributions of intensity and total transmission for a single-incident channel. PMID:24516156

  11. Dynamics of the Anderson model for dilute magnetic alloys: A quantum Monte Carlo and maximum entropy study

    SciTech Connect

    Silver, R.N.; Gubernatis, J.E.; Sivia, D.S. ); Jarrell, M. . Dept. of Physics)

    1990-01-01

    In this article we describe the results of a new method for calculating the dynamical properties of the Anderson model. QMC generates data about the Matsubara Green's functions in imaginary time. To obtain dynamical properties, one must analytically continue these data to real time. This is an extremely ill-posed inverse problem similar to the inversion of a Laplace transform from incomplete and noisy data. Our method is a general one, applicable to the calculation of dynamical properties from a wide variety of quantum simulations. We use Bayesian methods of statistical inference to determine the dynamical properties based on both the QMC data and any prior information we may have such as sum rules, symmetry, high frequency limits, etc. This provides a natural means of combining perturbation theory and numerical simulations in order to understand dynamical many-body problems. Specifically we use the well-established maximum entropy (ME) method for image reconstruction. We obtain the spectral density and transport coefficients over the entire range of model parameters accessible by QMC, with data having much larger statistical error than required by other proposed analytic continuation methods.

  12. Kolmogorov Turbulence Defeated by Anderson Localization for a Bose-Einstein Condensate in a Sinai-Oscillator Trap.

    PubMed

    Ermann, Leonardo; Vergini, Eduardo; Shepelyansky, Dima L

    2017-08-04

    We study the dynamics of a Bose-Einstein condensate in a Sinai-oscillator trap under a monochromatic driving force. Such a trap is formed by a harmonic potential and a repulsive disk located in the center vicinity corresponding to the first experiments of condensate formation by Ketterle and co-workers in 1995. We allow that the external driving allows us to model the regime of weak wave turbulence with the Kolmogorov energy flow from low to high energies. We show that in a certain regime of weak driving and weak nonlinearity such a turbulent energy flow is defeated by the Anderson localization that leads to localization of energy on low energy modes. This is in a drastic contrast to the random phase approximation leading to energy flow to high modes. A critical threshold is determined above which the turbulent flow to high energies becomes possible. We argue that this phenomenon can be studied with ultracold atoms in magneto-optical traps.

  13. Anderson acceleration of the Jacobi iterative method: An efficient alternative to Krylov methods for large, sparse linear systems

    SciTech Connect

    Pratapa, Phanisri P.; Suryanarayana, Phanish; Pask, John E.

    2015-12-01

    We employ Anderson extrapolation to accelerate the classical Jacobi iterative method for large, sparse linear systems. Specifically, we utilize extrapolation at periodic intervals within the Jacobi iteration to develop the Alternating Anderson–Jacobi (AAJ) method. We verify the accuracy and efficacy of AAJ in a range of test cases, including nonsymmetric systems of equations. We demonstrate that AAJ possesses a favorable scaling with system size that is accompanied by a small prefactor, even in the absence of a preconditioner. In particular, we show that AAJ is able to accelerate the classical Jacobi iteration by over four orders of magnitude, with speed-ups that increase as the system gets larger. Moreover, we find that AAJ significantly outperforms the Generalized Minimal Residual (GMRES) method in the range of problems considered here, with the relative performance again improving with size of the system. As a result, the proposed method represents a simple yet efficient technique that is particularly attractive for large-scale parallel solutions of linear systems of equations.

  14. Nailing the Coffin Shut on Doubts that Violent Video Games Stimulate Aggression ∼Comment on Anderson et al. (2010).

    PubMed Central

    Huesmann, L. Rowell

    2010-01-01

    Over the past half-century the mass media, including video games, have become important socializers of children. Observational learning theory has evolved into social-cognitive information processing models that explain that what a child observes in any venue has both short-term and long-term influences on the child's behaviors and cognitions. Anderson's (2010) extensive meta-analysis of the effects of violent video games confirms what these theories predict and what prior research about other violent mass media has found – that violent video games stimulate aggression in the players in the short run and increase the risk for aggressive behaviors by the players later in life. The effects occur for males and females and for children growing up in Eastern or Western cultures. The effects are strongest for the best studies. Contrary to some critics' assertions, the meta-analysis is methodologically sound and comprehensive. Yet the results are unlikely to change the critics' views or the public's perception that the issue is undecided because there are some studies that have yielded null effects, because many people are concerned that the implications of the research threaten freedom of expression, and because many people have their identities or self-interests closely tied to violent video games. PMID:20192555

  15. Gadolinium enhanced cardiovascular magnetic resonance in Anderson-Fabry disease. Evidence for a disease specific abnormality of the myocardial interstitium.

    PubMed

    Moon, James C C; Sachdev, Bhavesh; Elkington, Andrew G; McKenna, William J; Mehta, Atul; Pennell, Dudley J; Leed, Philip J; Elliott, Perry M

    2003-12-01

    Anderson-Fabry Disease (AFD), an X-linked disorder of sphingolipid metabolism, is a cause of idiopathic left ventricular hypertrophy but the mechanism of hypertrophy is poorly understood. Gadolinium enhanced cardiovascular magnetic resonance can detect focal myocardial fibrosis. We hypothesised that hyperenhancement would be present in AFD. Eighteen males (mean 43+/-14 years) and eight female heterozygotes (mean 48+/-12 years) with AFD underwent cine and late gadolinium cardiovascular magnetic resonance. Nine male (50%) had myocardial hyperenhancement ranging from 3.4% to 20.6% (mean 7.7+/-5.7%) of total myocardium; in males, percentage hyperenhancement related to LV mass index (r=0.78, P=0.0002) but not to ejection fraction or left ventricular volumes. Lesser hyperenhancement was also found in four (50%) heterozygous females (mean 4.6%). In 12 (92%) patients with abnormal gadolinium uptake, hyperenhancement occurred in the basal infero-lateral wall where, unlike myocardial infarction, it was not sub-endocardial. In two male patients with severe LVH (left ventricular hypertrophy) and systolic impairment there was additional hyperenhancement in other myocardial segments. These observations suggests that myocardial fibrosis occurs in AFD and may contribute to the hypertrophy and the natural history of the disease.

  16. Typical Value of Susceptibilities in the Three Dimensional Edwards-Anderson Spin Glass Model in an External Field

    NASA Astrophysics Data System (ADS)

    Feng, Sheng; Tam, Ka-Ming; Fang, Ye; Ramanujam, J.; Moreno, Juana; Jarrell, Mark

    2015-03-01

    We study the Edwards-Anderson model on a simple cubic lattice with a finite constant external field using a Monte Carlo simulation code, which employs graphics processing units to dramatically speedup the simulation. Conventional indicators, such as the Binder ratio and correlation length, do not show any signs of a phase transition. We also studied R12, or the ratio of spin glass susceptibilities at finite wavenumbers, and show it is quite noisy that a systematic analysis cannot come to clear conclusion. This is largely due to the fact that the susceptibilities follow a broad, fat-tailed distribution, and the average is possibly dominated by rare events. Therefore we propose to study the typical value of these parameters by taking the geometric average over different disorder realizations, and compare it with the linear average measurements. We argue that the typical value should be also studied in additional to conventional linear average value, to provide another perspective for the study of phase transition in spin glasses. This work is sponsored by the NSF EPSCoR Cooperative Agreement No. EPS-1003897 with additional support from the Louisiana Board of Regents.

  17. Genomic organization and reproductive regulation of a large lipid transfer protein in the varroa mite, Varroa destructor (Anderson & Trueman).

    PubMed

    Cabrera, A R; Shirk, P D; Duehl, A J; Donohue, K V; Grozinger, C M; Evans, J D; Teal, P E A

    2013-10-01

    The complete genomic region and corresponding transcript of the most abundant protein in phoretic varroa mites, Varroa destructor (Anderson & Trueman), were sequenced and have homology with acarine hemelipoglycoproteins and the large lipid transfer protein (LLTP) super family. The genomic sequence of VdLLTP included 14 introns and the mature transcript coded for a predicted polypeptide of 1575 amino acid residues. VdLLTP shared a minimum of 25% sequence identity with acarine LLTPs. Phylogenetic assessment showed VdLLTP was most closely related to Metaseiulus occidentalis vitellogenin and LLTP proteins of ticks; however, no heme binding by VdLLTP was detected. Analysis of lipids associated with VdLLTP showed that it was a carrier for free and esterified C12 -C22 fatty acids from triglycerides, diacylglycerides and monoacylglycerides. Additionally, cholesterol and β-sitosterol were found as cholesterol esters linked to common fatty acids. Transcript levels of VdLLTP were 42 and 310 times higher in phoretic female mites when compared with males and quiescent deutonymphs, respectively. Coincident with initiation of the reproductive phase, VdLLTP transcript levels declined to a third of those in phoretic female mites. VdLLTP functions as an important lipid transporter and should provide a significant RNA interference target for assessing the control of varroa mites. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  18. Anderson-Bogoliubov phonons in the inner crust of neutron stars: Dipole excitation in a spherical Wigner-Seitz cell

    NASA Astrophysics Data System (ADS)

    Inakura, Tsunenori; Matsuo, Masayuki

    2017-08-01

    Background: The Anderson-Bogoliubov (AB) phonon, called also the superfluid phonon, has attracted attentions since it may influence the thermal conductivity and other properties of the inner crust of neutron stars. However, there are a limited number of microscopic studies of the AB phonon where the presence of clusters is explicitly taken into account. Purpose: We intend to clarify how the presence of clusters affects the AB phonon in order to obtain microscopic information relevant to the coupling between the AB phonon and the lattice phonon. Methods: The Hartree-Fock-Bogoliubov model and the quasiparticle random-phase approximation formulated in a spherical Wigner-Seitz cell are adopted to describe neutron superfluidity and associated collective excitations. We perform systematic numerical calculations for dipole excitation by varying the neutron chemical potential and the number of protons in a cell. Results: The model predicts systematic emergence of the dipole AB phonon mode, which, however, exhibits strong suppression of phonon amplitude inside the cluster. We find also that the phonon amplitude around the cluster surface varies with the neutron density. At higher neutron densities (≳0.006 fm-3) the AB phonon mode exhibits behavior similar to the pygmy dipole resonance in neutron-rich nuclei. Conclusions: The dipole AB phonon mode does not penetrate into the clusters. This suggests that the coupling between the AB phonon and the lattice phonon may be weak.

  19. Anderson acceleration of the Jacobi iterative method: An efficient alternative to Krylov methods for large, sparse linear systems

    DOE PAGES

    Pratapa, Phanisri P.; Suryanarayana, Phanish; Pask, John E.

    2015-12-01

    We employ Anderson extrapolation to accelerate the classical Jacobi iterative method for large, sparse linear systems. Specifically, we utilize extrapolation at periodic intervals within the Jacobi iteration to develop the Alternating Anderson–Jacobi (AAJ) method. We verify the accuracy and efficacy of AAJ in a range of test cases, including nonsymmetric systems of equations. We demonstrate that AAJ possesses a favorable scaling with system size that is accompanied by a small prefactor, even in the absence of a preconditioner. In particular, we show that AAJ is able to accelerate the classical Jacobi iteration by over four orders of magnitude, with speed-upsmore » that increase as the system gets larger. Moreover, we find that AAJ significantly outperforms the Generalized Minimal Residual (GMRES) method in the range of problems considered here, with the relative performance again improving with size of the system. As a result, the proposed method represents a simple yet efficient technique that is particularly attractive for large-scale parallel solutions of linear systems of equations.« less

  20. Magnetic, optical, and electron transport properties of n -type CeO2: Small polarons versus Anderson localization

    NASA Astrophysics Data System (ADS)

    Kolodiazhnyi, Taras; Charoonsuk, Thitirat; Seo, Yu-Seong; Chang, Suyong; Vittayakorn, Naratip; Hwang, Jungseek

    2017-01-01

    We report magnetic susceptibility, electrical conductivity and optical absorption of Ce1 -xMxO2 where M = Nb,Ta and 0 ≤x ≤0.03 . The dc conductivity follows a simple thermally activated Arrhenius-type behavior in the T =70 -700 K range with a change in slope at T*≈155 K. The high-temperature activation energy shows gradual increase from ≈170 to 220 meV as the dopant concentration increases. The activation energy of the low-temperature conductivity shows a broad minimum of ≈77 meV at x ≈0.01 . Electron transport and localization mechanisms are analyzed in the framework of the Holstein small polaron, Anderson localization, and Jahn-Teller distortion models. The fit to the small polaron mobility is dramatically improved when, instead of the longitudinal phonons, the transverse optical phonons are considered in the phonon-assisted electron transport. This serves as an indirect evidence of a strong 4 f1 orbital interaction with the oxygen ligands, similar to the case of PrO2. Based on comparison of the experimental data to the models, it is proposed that the defect-induced random electric fields make the dominant contribution to the electron localization in donor-doped ceria.

  1. Quantum criticality of the two-channel pseudogap Anderson model: universal scaling in linear and non-linear conductance.

    PubMed

    Wu, Tsan-Pei; Wang, Xiao-Qun; Guo, Guang-Yu; Anders, Frithjof; Chung, Chung-Hou

    2016-05-05

    The quantum criticality of the two-lead two-channel pseudogap Anderson impurity model is studied. Based on the non-crossing approximation (NCA) and numerical renormalization group (NRG) approaches, we calculate both the linear and nonlinear conductance of the model at finite temperatures with a voltage bias and a power-law vanishing conduction electron density of states, ρc(ω) proportional |ω − μF|(r) (0 < r < 1) near the Fermi energy μF. At a fixed lead-impurity hybridization, a quantum phase transition from the two-channel Kondo (2CK) to the local moment (LM) phase is observed with increasing r from r = 0 to r = rc < 1. Surprisingly, in the 2CK phase, different power-law scalings from the well-known [Formula: see text] or [Formula: see text] form is found. Moreover, novel power-law scalings in conductances at the 2CK-LM quantum critical point are identified. Clear distinctions are found on the critical exponents between linear and non-linear conductance at criticality. The implications of these two distinct quantum critical properties for the non-equilibrium quantum criticality in general are discussed.

  2. Hierarchical equations of motion approach to transport through an Anderson impurity coupled to interacting Luttinger liquid leads

    NASA Astrophysics Data System (ADS)

    Okamoto, Jun-ichi; Mathey, Ludwig; Härtle, Rainer

    2016-12-01

    We generalize the hierarchical equations of motion method to study electron transport through a quantum dot or molecule coupled to one-dimensional interacting leads that can be described as Luttinger liquids. Such leads can be realized, for example, by quantum wires or fractional quantum Hall edge states. In comparison to noninteracting metallic leads, Luttinger liquid leads involve many-body correlations and the single-particle tunneling density of states shows a power-law singularity at the chemical potential. Using the generalized hierarchical equations of motion method, we assess the importance of the singularity and the next-to-leading order many-body correlations. To this end, we compare numerically converged results with second- and first-order results of the hybridization expansion that is inherent to our method. As a test case, we study transport through a single-level quantum dot or molecule that can be described by an Anderson impurity model. Cotunneling effects turn out to be most pronounced for attractive interactions in the leads or repulsive ones if an excitonic coupling between the dot and the leads is realized. We also find that an interaction-induced negative differential conductance near the Coulomb blockade thresholds is slightly suppressed as compared to a first-order and/or rate equation result. Moreover, we find that the two-particle (n -particle) correlations enter as a second-order (n -order) effect and are, thus, not very pronounced at the high temperatures and parameters that we consider.

  3. Kolmogorov Turbulence Defeated by Anderson Localization for a Bose-Einstein Condensate in a Sinai-Oscillator Trap

    NASA Astrophysics Data System (ADS)

    Ermann, Leonardo; Vergini, Eduardo; Shepelyansky, Dima L.

    2017-08-01

    We study the dynamics of a Bose-Einstein condensate in a Sinai-oscillator trap under a monochromatic driving force. Such a trap is formed by a harmonic potential and a repulsive disk located in the center vicinity corresponding to the first experiments of condensate formation by Ketterle and co-workers in 1995. We allow that the external driving allows us to model the regime of weak wave turbulence with the Kolmogorov energy flow from low to high energies. We show that in a certain regime of weak driving and weak nonlinearity such a turbulent energy flow is defeated by the Anderson localization that leads to localization of energy on low energy modes. This is in a drastic contrast to the random phase approximation leading to energy flow to high modes. A critical threshold is determined above which the turbulent flow to high energies becomes possible. We argue that this phenomenon can be studied with ultracold atoms in magneto-optical traps.

  4. Hydrological cycle.

    PubMed

    Gonçalves, H C; Mercante, M A; Santos, E T

    2011-04-01

    The Pantanal hydrological cycle holds an important meaning in the Alto Paraguay Basin, comprising two areas with considerably diverse conditions regarding natural and water resources: the Plateau and the Plains. From the perspective of the ecosystem function, the hydrological flow in the relationship between plateau and plains is important for the creation of reproductive and feeding niches for the regional biodiversity. In general, river declivity in the plateau is 0.6 m/km while declivity on the plains varies from 0.1 to 0.3 m/km. The environment in the plains is characteristically seasonal and is home to an exuberant and abundant diversity of species, including some animals threatened with extinction. When the flat surface meets the plains there is a diminished water flow on the riverbeds and, during the rainy season the rivers overflow their banks, flooding the lowlands. Average annual precipitation in the Basin is 1,396 mm, ranging from 800 mm to 1,600 mm, and the heaviest rainfall occurs in the plateau region. The low drainage capacity of the rivers and lakes that shape the Pantanal, coupled with the climate in the region, produce very high evaporation: approximately 60% of all the waters coming from the plateau are lost through evaporation. The Alto Paraguay Basin, including the Pantanal, while boasting an abundant availability of water resources, also has some spots with water scarcity in some sub-basins, at different times of the year. Climate conditions alone are not enough to explain the differences observed in the Paraguay River regime and some of its tributaries. The complexity of the hydrologic regime of the Paraguay River is due to the low declivity of the lands that comprise the Mato Grosso plains and plateau (50 to 30 cm/km from east to west and 3 to 1.5 cm/km from north to south) as well as the area's dimension, which remains periodically flooded with a large volume of water.

  5. To see a world in a grain of sand: elucidating the pathophysiology of Anderson-Fabry disease through investigations of a cellular model.

    PubMed

    Pastores, Gregory M; Hughes, Derralynn A

    2009-02-01

    Thomaidis and colleagues have created a cellular model of Anderson-Fabry disease by 'silencing' alpha-galactosidase A (AGAL) activity in human tubular epithelial cells. Increased membrane globotriaosylceramide (Gb3/CD77) expression was observed; it is suggested that this finding may be potentially useful as a surrogate marker of disease severity. Decreased membrane Gb3/CD77 expression was observed following agalsidase-alpha treatment, providing evidence of changes in cellular phenotype in response to enzyme therapy.

  6. Management of Gustilo Anderson III B open tibial fractures by primary fascio-septo-cutaneous local flap and primary fixation: The ‘fix and shift’ technique

    PubMed Central

    Ramasamy, P R

    2017-01-01

    Background: Open fractures of tibia have posed great difficulty in managing both the soft tissue and the skeletal components of the injured limb. Gustilo Anderson III B open tibial fractures are more difficult to manage than I, II, and III A fractures. Stable skeletal fixation with immediate soft tissue cover has been the key to the successful outcome in treating open tibial fractures, in particular, Gustilo Anderson III B types. If the length of the open wound is larger and if the exposed surface of tibial fracture and tibial shaft is greater, then the management becomes still more difficult. Materials and Methods: Thirty six Gustilo Anderson III B open tibial fractures managed between June 2002 and December 2013 with “fix and shift” technique were retrospectively reviewed. All the 36 patients managed by this technique had open wounds measuring >5 cm (post debridement). Under fix and shift technique, stable fixation involved primary external fixator application or primary intramedullary nailing of the tibial fracture and immediate soft tissue cover involved septocutaneous shift, i.e., shifting of fasciocutaneous segments based on septocutaneous perforators. Results: Primary fracture union rate was 50% and reoperation rate (bone stimulating procedures) was 50%. Overall fracture union rate was 100%. The rate of malunion was 14% and deep infection was 16%. Failure of septocutaneous shift was 2.7%. There was no incidence of amputation. Conclusion: Management of Gustilo Anderson III B open tibial fractures with “fix and shift” technique has resulted in better outcome in terms of skeletal factors (primary fracture union, overall union, and time for union and malunion) and soft tissue factors (wound healing, flap failure, access to secondary procedures, and esthetic appearance) when compared to standard methods adopted earlier. Hence, “fix and shift” could be recommended as one of the treatment modalities for open III B tibial fractures. PMID:28216752

  7. The anderson's rotating interferometer and its application to binary star measurements. (French Title: L'interféromètre à rotation de john august anderson (1876-1956) et son application - la tentative de résolution de nouvelles binaires)

    NASA Astrophysics Data System (ADS)

    Bonneau, D.

    2011-12-01

    Following the tests of interferometric observations carried out by Albert A. Michelson with the 2.5 m telescope of the Mount Wilson, George. E. Hale thinks that this technique could be applied to the measurement of close double stars. He asks John A. Anderson to produce an instrument allowing such measurements. The principle of the ocular rotating interferometer and the way of using it for the measurement of double stars are first described. Then the effects of atmospheric dispersion on the observation of the stellar interference fringes and the remedy that Anderson implements to compensate it are described. Images of the Anderson's interferometer are used to present the instrument and to describe its operation. Installed at the 2,5 m telescope, this instrument was used by Anderson and Paul W. Merrill to resolve the spectroscopic binary Capella for the first time, like a 'visual binary'. Moreover, Merrill took the measurement of two difficult visual pairs discovered by Aitken (kap UMa = A 1585 and nu2 Boo = A 1634) and tried to resolve some new visual binaries among stars known as binary spectroscopic, stars with composite spectra, variable stars and some bright stars, which led him to publish a list of 73 stars finally found simple. Finally, the remarks made by Merrill in conclusion of his work will be analyzed.

  8. The Anderson impurity model out-of-equilibrium: Assessing the accuracy of simulation techniques with an exact current-occupation relation

    NASA Astrophysics Data System (ADS)

    Agarwalla, Bijay Kumar; Segal, Dvira

    2017-08-01

    We study the interacting, symmetrically coupled single impurity Anderson model. By employing the nonequilibrium Green's function formalism, we reach an exact relationship between the steady-state charge current flowing through the impurity (dot) and its occupation. We argue that the steady-state current-occupation relation can be used to assess the consistency of simulation techniques and identify spurious transport phenomena. We test this relation in two different model variants: First, we study the Anderson-Holstein model in the strong electron-vibration coupling limit using the polaronic quantum master equation method. We find that the current-occupation relation is violated numerically in standard calculations, with simulations bringing up incorrect transport effects. Using a numerical procedure, we resolve the problem efficiently. Second, we simulate the Anderson model with electron-electron interaction on the dot using a deterministic numerically exact time-evolution scheme. Here, we observe that the current-occupation relation is satisfied in the steady-state limit—even before results converge to the exact limit.

  9. Monte Carlo Simulation of three dimensional Edwards Anderson model with multi-spin coding and parallel tempering using MPI and CUDA

    NASA Astrophysics Data System (ADS)

    Feng, Sheng; Fang, Ye; Tam, Ka-Ming; Thakur, Bhupender; Yun, Zhifeng; Tomko, Karen; Moreno, Juana; Ramanujam, Jagannathan; Jarrell, Mark

    2013-03-01

    The Edwards Anderson model is a typical example of random frustrated system. It has been a long standing problem in computational physics due to its long relaxation time. Some important properties of the low temperature spin glass phase are still poorly understood after decades of study. The recent advances of GPU computing provide a new opportunity to substantially improve the simulations. We developed an MPI-CUDA hybrid code with multi-spin coding for parallel tempering Monte Carlo simulation of Edwards Anderson model. Since the system size is relatively small, and a large number of parallel replicas and Monte Carlo moves are required, the problem suits well for modern GPUs with CUDA architecture. We use the code to perform an extensive simulation on the three-dimensional Edwards Anderson model with an external field. This work is funded by the NSF EPSCoR LA-SiGMA project under award number EPS-1003897. This work is partly done on the machines of Ohio Supercomputer Center.

  10. Much ado about nothing: the misestimation and overinterpretation of violent video game effects in eastern and western nations: comment on Anderson et al. (2010).

    PubMed

    Ferguson, Christopher J; Kilburn, John

    2010-03-01

    The issue of violent video game influences on youth violence and aggression remains intensely debated in the scholarly literature and among the general public. Several recent meta-analyses, examining outcome measures most closely related to serious aggressive acts, found little evidence for a relationship between violent video games and aggression or violence. In a new meta-analysis, C. A. Anderson et al. (2010) questioned these findings. However, their analysis has several methodological issues that limit the interpretability of their results. In their analysis, C. A. Anderson et al. included many studies that do not relate well to serious aggression, an apparently biased sample of unpublished studies, and a "best practices" analysis that appears unreliable and does not consider the impact of unstandardized aggression measures on the inflation of effect size estimates. They also focused on bivariate correlations rather than better controlled estimates of effects. Despite a number of methodological flaws that all appear likely to inflate effect size estimates, the final estimate of r = .15 is still indicative of only weak effects. Contrasts between the claims of C. A. Anderson et al. (2010) and real-world data on youth violence are discussed.

  11. The Anderson impurity model out-of-equilibrium: Assessing the accuracy of simulation techniques with an exact current-occupation relation.

    PubMed

    Agarwalla, Bijay Kumar; Segal, Dvira

    2017-08-07

    We study the interacting, symmetrically coupled single impurity Anderson model. By employing the nonequilibrium Green's function formalism, we reach an exact relationship between the steady-state charge current flowing through the impurity (dot) and its occupation. We argue that the steady-state current-occupation relation can be used to assess the consistency of simulation techniques and identify spurious transport phenomena. We test this relation in two different model variants: First, we study the Anderson-Holstein model in the strong electron-vibration coupling limit using the polaronic quantum master equation method. We find that the current-occupation relation is violated numerically in standard calculations, with simulations bringing up incorrect transport effects. Using a numerical procedure, we resolve the problem efficiently. Second, we simulate the Anderson model with electron-electron interaction on the dot using a deterministic numerically exact time-evolution scheme. Here, we observe that the current-occupation relation is satisfied in the steady-state limit-even before results converge to the exact limit.

  12. Reduced Right Ventricular Native Myocardial T1 in Anderson-Fabry Disease: Comparison to Pulmonary Hypertension and Healthy Controls

    PubMed Central

    Pagano, Joseph J.; Chow, Kelvin; Khan, Aneal; Michelakis, Evangelos; Paterson, Ian; Oudit, Gavin Y.; Thompson, Richard B.

    2016-01-01

    Aims Anderson-Fabry disease (AFD) is characterized by progressive multiorgan accumulation of intracellular sphingolipids due to α-galactosidase A enzyme deficiency, resulting in progressive ventricular hypertrophy, heart failure, arrhythmias, and death. Decreased native (non-contrast) left ventricular (LV) T1 (longitudinal relaxation time) with MRI discriminates AFD from healthy controls or other presentations of concentric hypertrophy, but the right ventricle (RV) has not been studied. The aims of the current study were to evaluate native RV T1 values in AFD, with a goal of better understanding the pathophysiology of RV involvement. Methods and Results Native T1 values were measured in the inferior RV wall (RVI), interventricular septum (IVS), and inferior LV (LVI) in patients with AFD, patients with pulmonary hypertension, who provided an alternative RV pathological process for comparison, and healthy controls. A minimum wall thickness of 4 mm was selected to minimize partial volume errors in tissue T1 analysis. T1 analysis was performed in 6 subjects with AFD, 6 subjects with PH, and 21 controls. Native T1 values were shorter (adjusted p<0.05 for all comparisons), independent of location, in subjects with AFD (RVI-T1 = 1096±49 ms, IVS-T1 = 1053±41 ms, LVI-T1 = 1072±44 ms) compared to both PH (RVI-T1 = 1239±41 ms, IVS-T1 = 1280±123 ms, LVI-T1 = 1274±57 ms) and HC (IVS-T1 = 1180±60 ms, LVI-T1 = 1183±45 ms). RVI measurements were not possible in controls due to insufficient wall thickness. Conclusion Native T1 values appear similarly reduced in the left and right ventricles of individuals with AFD and RV wall thickening, suggesting a common pathology. In contrast, individuals with PH and thickened RVs showed increased native T1 values in both ventricles, suggestive of fibrosis. PMID:27305064

  13. Molecular analysis and intestinal expression of SAR1 genes and proteins in Anderson's disease (Chylomicron retention disease)

    PubMed Central

    2011-01-01

    Background Anderson's disease (AD) or chylomicron retention disease (CMRD) is a very rare hereditary lipid malabsorption syndrome. In order to discover novel mutations in the SAR1B gene and to evaluate the expression, as compared to healthy subjects, of the Sar1 gene and protein paralogues in the intestine, we investigated three previously undescribed individuals with the disease. Methods The SAR1B, SAR1A and PCSK9 genes were sequenced. The expression of the SAR1B and SAR1A genes in intestinal biopsies of both normal individuals and patients was measured by RTqPCR. Immunohistochemistry using antibodies to recombinant Sar1 protein was used to evaluate the expression and localization of the Sar1 paralogues in the duodenal biopsies. Results Two patients had a novel SAR1B mutation (p.Asp48ThrfsX17). The third patient, who had a previously described SAR1B mutation (p.Leu28ArgfsX7), also had a p.Leu21dup variant of the PCSK9 gene. The expression of the SAR1B gene in duodenal biopsies from an AD/CMRD patient was significantly decreased whereas the expression of the SAR1A gene was significantly increased, as compared to healthy individuals. The Sar1 proteins were present in decreased amounts in enterocytes in duodenal biopsies from the patients as compared to those from healthy subjects. Conclusions Although the proteins encoded by the SAR1A and SAR1B genes are 90% identical, the increased expression of the SAR1A gene in AD/CMRD does not appear to compensate for the lack of the SAR1B protein. The PCSK9 variant, although reported to be associated with low levels of cholesterol, does not appear to exert any additional effect in this patient. The results provide further insight into the tissue-specific nature of AD/CMRD. PMID:21235735

  14. Italian version of the M.D. Anderson Symptom Inventory--Head and Neck Module: linguistic validation.

    PubMed

    Greco, A; Orlandi, E; Mirabile, A; Takanen, S; Fallai, C; Iacovelli, N A; Rimedio, A; Russi, E; Sala, M; Monzani, D; Rosenthal, D I; Gunn, G B; Steca, P; Licitra, L; Bossi, P

    2015-12-01

    Head and neck cancer (HNC) patients can experience symptoms due to the tumor itself or to the treatment, with an impact on health-related quality of life (HRQoL). Patient-reported outcome (PRO) measures pertaining to HRQoL are used in medical research and to support clinical decisions. PRO instrument applicability and cultural adaptation must be tested for each population. The aim of this study is to linguistically validate the Italian translation of the M.D. Anderson Symptom Inventory--Head and Neck Module (MDASI-HN). Following forward and backward translation of the items of the English MDASI-HN into Italian, it was administered along with a cognitive debriefing to HNC patients able to read and understand Italian language. Individual and group responses are presented using descriptive statistics. From May 2013 through September 2013, 56 patients with HNC (18 during curative treatment, 20 in palliative chemotherapy, and 18 in follow-up period) completed the MDASI-HN followed by accompanying cognitive debriefing. Ninety-nine percent of the individual MDASI-HN items were completed. Average time to complete the MDASI-HN was 8.5 min (range 3-15). Results suggested overall ease of completion, relevance, and comprehensibleness of this translated self-report instrument in this Italian patient population. The Italian version of the MDASI-HN is linguistically valid; future research should explore dimensionality, reliability, and convergent, discriminant, and predictive validity of this patient-reported instrument, in order to use this translated version in outcomes research and clinical settings.

  15. Interplay of long-range and short-range Coulomb interactions in an Anderson-Mott insulator

    NASA Astrophysics Data System (ADS)

    Baćani, Mirko; Novak, Mario; Orbanić, Filip; Prša, Krunoslav; Kokanović, Ivan; Babić, Dinko

    2017-07-01

    In this paper, we tackle the complexity of coexisting disorder and Coulomb electron-electron interactions (CEEIs) in solids by addressing a strongly disordered system with intricate CEEIs and a screening that changes both with charge carrier doping level Q and temperature T . We report on an experimental comparative study of the T dependencies of the electrical conductivity σ and magnetic susceptibility χ of polyaniline pellets doped with dodecylbenzenesulfonic acid over a wide range. This material is special within the class of doped polyaniline by exhibiting in the electronic transport a crossover between a low-T variable range hopping (VRH) and a high-T nearest-neighbor hopping (NNH) well below room temperature. Moreover, there is evidence of a soft Coulomb gap ΔC in the disorder band, which implies the existence of a long-range CEEI. Simultaneously, there is an onsite CEEI manifested as a Hubbard gap U and originating in the electronic structure of doped polyaniline, which consists of localized electron states with dynamically varying occupancy. Therefore, our samples represent an Anderson-Mott insulator in which long-range and short-range CEEIs coexist. The main result of the study is the presence of a crossover between low- and high-T regimes not only in σ (T ) but also in χ (T ) , the crossover temperature T* being essentially the same for both observables over the entire doping range. The relatively large electron localization length along the polymer chains results in U being small, between 12 and 20 meV for the high and low Q , respectively. Therefore, the thermal energy at T* is sufficiently large to lead to an effective closing of the Hubbard gap and the consequent appearance of NNH in the electronic transport within the disorder band. ΔC is considerably larger than U , decreasing from 190 to 30 meV as Q increases, and plays the role of an activation energy in the NNH.

  16. Psychometric Validation of the M. D. Anderson Symptom Inventory-Head and Neck Module in the Spanish Language.

    PubMed

    Sánchez, Daniel; Chala, Andrés; Alvarez, Andrés; Payan, Catalina; Mendoza, Tito; Cleeland, Charles; Sanabria, Alvaro

    2016-06-01

    The assessment of cancer-related symptoms requires culturally adapted and psychometrically validated symptom assessment tools. The M. D. Anderson Symptom Inventory-Head and Neck Module (MDASI-HN) is a useful instrument for measuring symptom burden that was specifically developed for head and neck cancer patients. To validate the Spanish version of the MDASI-HN. We evaluated the psychometric features of the MDASI-HN in patients with head and neck cancer. We evaluated the item-scale correlations and the internal consistency. We conducted principal axis factoring to identify the underlying dimensions as a measure of construct validity. The convergence/concurrent validity was assessed with the University of Washington Quality of Life Questionnaire for Head and Neck Patients, and known-group validity and test-retest reliability also were assessed. One hundred thirty patients were included. The mean ± SD age was 60.5 ± 13.6 years; 68% of patients were male, 42% had laryngeal tumors, and 45.9% had Stage III tumors. Forty-seven percent of the patients underwent surgery, 55% underwent radiotherapy, and 36% underwent chemotherapy. The global Cronbach alpha for the HN module was 0.81. The factor analysis identified two factors (Factor 1: speech, mucus, coughing, and constipation; Factor 2: teeth, taste, sores, swallowing, and skin). The correlation with the global score of the University of Washington Quality of Life was -0.68. The difference in the MDASI-HN scores according to Eastern Cooperative Oncology Group performance status was statistically significant (2.72 vs. 4.01, P = 0.006). The intraclass test-retest correlation was 0.62. The Spanish version of the MDASI-HN is reliable and valid for evaluating cancer-related symptoms in head and neck cancer patients. Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

  17. Linguistic Validation of the Turkish Version of the M.D. Anderson Symptom Inventory - Head and Neck Cancer Module

    PubMed Central

    Brandon Gunn, G.; Atalar, Banu; Mendoza, Tito R.; Cleeland, Charles S.; Selek, Uğur; Özyar, Enis; Rosenthal, David I.

    2016-01-01

    Background: The use of patient symptom reports with frequent symptom assessment may be preferred over the more commonly used health-related quality of life questionnaires. Aims: We sought to linguistically validate the Turkish version of the M.D. Anderson Symptom Inventory-Head and Neck module (MDASI-HN) patient reported outcome questionnaire. Study Design: Validation study. Methods: Following standard forward and backward translation of the original and previously validated English MDASI-HN into a Turkish version (T-MDASI-HN), it was administered to patients with head and neck cancer able to read and understand Turkish. Patients were then cognitively debriefed to evaluate their understanding and comprehension of the T-MDASI-HN. Individual and group responses are presented using descriptive statistics. Results: Twenty-six participants with head and neck cancer completed the T-MDASIHN and accompanying cognitive debriefing. Overall, 97 percent of the individual TMDASI-HN items were completed. Average recorded time to complete the 28 item TMDASI-HN questionnaire was 5.4 minutes (range 2–10). Average overall ease of completion, understandability, and acceptability were favorably rated at 1.0, 1.1, and 0.2, respectively, on scales from 0 to 10. Only 5 of the 26 of participants reported trouble completing any single questionnaire items, namely the “difficulty remembering” item for 3 individuals. Conclusion: The T-MDASI-HN is linguistically valid with ease of completion, relevance, comprehensibility, and applicability and it can be a useful clinical and research tool. PMID:27308079

  18. Ischemic stroke in patients with gliomas at The University of Texas-M.D. Anderson Cancer Center.

    PubMed

    Kamiya-Matsuoka, Carlos; Cachia, David; Yust-Katz, Shlomit; Rodriguez, Yvo A; Garciarena, Pedro; Rodarte, Elsa M; Tremont-Lukats, Ivo W

    2015-10-01

    Patients with gliomas are at risk of cerebrovascular accidents (CVA) with potential consequences on survival, function, and local tumor control. Our objective was to provide information about CVA in patients with gliomas and to estimate survival in this group. We reviewed all adult glioma patients with ischemic CVA at the University of Texas-M.D. Anderson Cancer Center from 2003 through 2014. We extracted demographic, clinical, imaging, treatment and outcome data. We used descriptive summary data and estimated or compared survival rates where appropriate. 60 of 6500 patients (0.1%) with high-grade (HGG, n = 47) or low-grade glioma (LGG, n = 13) had ischemic CVA Thirty-two (53%) patients had postoperative strokes, and 20 (33%) had CVA after 2 weeks of surgery. Forty-one patients (68%) had gross total resection. For HGG and CVA, the poststroke median overall survival was 17 months versus 61 months in LGG and CVA (P = 0.03; hazard ratio (HR): 2.8; 95% CI 1.07-4.60). Survival stratified by modified Rankin Scale grade was significant (X(2) = 9.8, P = 0.007). Five patients received bevacizumab before stroke onset; none responded to antiangiogenic therapy. There was no stroke-related death. At our institution for 10 years, ischemic CVA in glioma patients was a rare complication, clearly associated in half of cases to surgery, and with a variable negative impact on performance status and neurologic function. In this group, patients with more neurological deficits lived less. The survival difference between and within subgroups was most likely due to tumor grade. More research is necessary to improve prevention of postoperative stroke in glioma patients.

  19. Bipolar mood cycles and lunar tidal cycles.

    PubMed

    Wehr, T A

    2017-01-24

    In 17 patients with rapid cycling bipolar disorder, time-series analyses detected synchronies between mood cycles and three lunar cycles that modulate the amplitude of the moon's semi-diurnal gravimetric tides: the 14.8-day spring-neap cycle, the 13.7-day declination cycle and the 206-day cycle of perigee-syzygies ('supermoons'). The analyses also revealed shifts among 1:2, 1:3, 2:3 and other modes of coupling of mood cycles to the two bi-weekly lunar cycles. These shifts appear to be responses to the conflicting demands of the mood cycles' being entrained simultaneously to two different bi-weekly lunar cycles with slightly different periods. Measurements of circadian rhythms in body temperature suggest a biological mechanism through which transits of one of the moon's semi-diurnal gravimetric tides might have driven the patients' bipolar cycles, by periodically entraining the circadian pacemaker to its 24.84-h rhythm and altering the pacemaker's phase-relationship to sleep in a manner that is known to cause switches from depression to mania.Molecular Psychiatry advance online publication, 24 January 2017; doi:10.1038/mp.2016.263.

  20. Bipolar Mood Cycles and Lunar Tidal Cycles

    PubMed Central

    Wehr, Thomas A.

    2016-01-01

    In seventeen patients with rapid cycling bipolar disorder, time-series analyses detected synchronies between mood cycles and three lunar cycles that modulate the amplitude of the moon’s semi-diurnal gravimetric tides: the 14.8-day spring-neap cycle, the 13.7-day declination cycle, and the 206-day cycle of perigee-syzygies (“supermoons”). The analyses also revealed shifts among 1:2, 1:3, 2:3 and other modes of coupling of mood cycles to the two bi-weekly lunar cycles. These shifts appear to be responses to the conflicting demands of the mood cycles’ being entrained simultaneously to two different bi-weekly lunar cycles with slightly different periods. Measurements of circadian rhythms in body temperature suggest a biological mechanism through which transits of one of the moon’s semi-diurnal gravimetric tides might have driven the patients’ bipolar cycles, by periodically entraining the circadian pacemaker to its 24.84-hour rhythm and altering the pacemaker’s phase-relationship to sleep in a manner that is known to cause switches from depression to mania. PMID:28115741