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1

Excitation of multiple resonances in 1D Anderson localized systems for efficient light amplification.  

PubMed

Excitation of hybridized multiple resonances can be an effective route for coherent light generation in irregular 1D systems larger than the localization length of light. Necklace states are often considered to have nonlocalized states. However, we propose that some hybridized/coupled states can have high-resonant tunneling with spatially extended fields. If strong localization properties are preserved in hybridized resonances, the excitation of such states allows for deposition of the excitation energy deep into the structure and spatial overlap with local gain regions. This result could allow for better utilizing hybridized resonances in biological or natural photonic systems. PMID:25723448

Choi, Seung Ho; Byun, Kyung Min; Kim, Young L

2015-03-01

2

Anderson localized optical fibers  

NASA Astrophysics Data System (ADS)

Anderson localization has been a subject of fascination and intense research for more than fifty years. It is highly desirable to harness its curious and interesting properties in practical applications. We have taken a step in this direction by using this phenomenon as the wave guiding mechanism in optical fibers. We have shown, both experimentally and numerically, that for a moderate amount of disorder in optical fibers, transverse localization results in an effective propagating beam diameter that is comparable to that of a typical index-guiding optical fiber.1, 2 In this work, we investigate the effect of macro-bending on the localization properties in a disordered polymer optical fiber both experimentally and numerically. We show that macro-bending in ranges of practical interest does not significantly affect the beam propagation in Anderson localized fibers as long as the strong localization dominates the effect of bending.

Karbasi, Salman; Koch, Karl W.; Mafi, Arash

2013-02-01

3

Gravitational Anderson localization.  

PubMed

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). PMID:23383775

Rothstein, Ira Z

2013-01-01

4

Anderson localization of light  

NASA Astrophysics Data System (ADS)

Over the past decade, the Anderson localization of light and a wide variety of associated phenomena have come to the forefront of research. Numerous investigations have been made into the underlying physics of how disorder affects transport in a crystalline lattice incorporating disorder. The physics involved relies on the analogy between the paraxial equation for electromagnetic waves and the Schrödinger equation describing quantum phenomena. Experiments have revealed how wavefunctions evolve during the localization process, and have led to discoveries of new physics that are universal to wave systems incorporating disorder. This Review summarizes the phenomena associated with the transverse localization of light, with an emphasis on the history, new ideas and future exploration of the field.

Segev, Mordechai; Silberberg, Yaron; Christodoulides, Demetrios N.

2013-03-01

5

Anderson localization makes adiabatic quantum optimization fail.  

PubMed

Understanding NP-complete problems is a central topic in computer science (NP stands for nondeterministic polynomial time). This is why adiabatic quantum optimization has attracted so much attention, as it provided a new approach to tackle NP-complete problems using a quantum computer. The efficiency of this approach is limited by small spectral gaps between the ground and excited states of the quantum computer's Hamiltonian. We show that the statistics of the gaps can be analyzed in a novel way, borrowed from the study of quantum disordered systems in statistical mechanics. It turns out that due to a phenomenon similar to Anderson localization, exponentially small gaps appear close to the end of the adiabatic algorithm for large random instances of NP-complete problems. This implies that unfortunately, adiabatic quantum optimization fails: The system gets trapped in one of the numerous local minima. PMID:20616043

Altshuler, Boris; Krovi, Hari; Roland, Jérémie

2010-07-13

6

Anderson localization makes adiabatic quantum optimization fail  

PubMed Central

Understanding NP-complete problems is a central topic in computer science (NP stands for nondeterministic polynomial time). This is why adiabatic quantum optimization has attracted so much attention, as it provided a new approach to tackle NP-complete problems using a quantum computer. The efficiency of this approach is limited by small spectral gaps between the ground and excited states of the quantum computer’s Hamiltonian. We show that the statistics of the gaps can be analyzed in a novel way, borrowed from the study of quantum disordered systems in statistical mechanics. It turns out that due to a phenomenon similar to Anderson localization, exponentially small gaps appear close to the end of the adiabatic algorithm for large random instances of NP-complete problems. This implies that unfortunately, adiabatic quantum optimization fails: The system gets trapped in one of the numerous local minima. PMID:20616043

Altshuler, Boris; Krovi, Hari; Roland, Jérémie

2010-01-01

7

ANDERSON LOCALIZATION OF ELECTROMAGNETIC WAVES IN CONFINED DISORDERED DIELECTRIC MEDIA  

E-print Network

ANDERSON LOCALIZATION OF ELECTROMAGNETIC WAVES IN CONFINED DISORDERED DIELECTRIC MEDIA MARIAN RUSEK, Poland 1. Introduction Scattering of electromagnetic waves from varoius kind of obstacles is rich experimental demonstration that Anderson localization of electromagnetic waves is possible in three

Rusek, Marian

8

Universal mechanism for Anderson and weak localization  

PubMed Central

Localization of stationary waves occurs in a large variety of vibrating systems, whether mechanical, acoustical, optical, or quantum. It is induced by the presence of an inhomogeneous medium, a complex geometry, or a quenched disorder. One of its most striking and famous manifestations is Anderson localization, responsible for instance for the metal-insulator transition in disordered alloys. Yet, despite an enormous body of related literature, a clear and unified picture of localization is still to be found, as well as the exact relationship between its many manifestations. In this paper, we demonstrate that both Anderson and weak localizations originate from the same universal mechanism, acting on any type of vibration, in any dimension, and for any domain shape. This mechanism partitions the system into weakly coupled subregions. The boundaries of these subregions correspond to the valleys of a hidden landscape that emerges from the interplay between the wave operator and the system geometry. The height of the landscape along its valleys determines the strength of the coupling between the subregions. The landscape and its impact on localization can be determined rigorously by solving one special boundary problem. This theory allows one to predict the localization properties, the confining regions, and to estimate the energy of the vibrational eigenmodes through the properties of one geometrical object. In particular, Anderson localization can be understood as a special case of weak localization in a very rough landscape. PMID:22927384

Filoche, Marcel; Mayboroda, Svitlana

2012-01-01

9

Spatio-temporal hybrid Anderson localization  

NASA Astrophysics Data System (ADS)

We address the localization of spatio-temporal wave packets in disordered waveguide arrays whereby temporal localization is mediated by nonlinearity while strong disorder provides Anderson statistical spatial localization. This combination of two different mechanisms allows localization to occur outside the range of parameters where diffraction, dispersion, and self-action have similar strengths, as required for the formation of standard spatio-temporal solitons. Under suitable conditions, nonlinearity is shown to weakly affect the statistically averaged spatial intensity distributions. In contrast, the temporal duration of the localized wave packets strongly depends on the level of disorder.

Lobanov, V. E.; Borovkova, O. V.; Kartashov, Y. V.; Szameit, A.

2014-12-01

10

Random photonics: True Anderson localization  

NASA Astrophysics Data System (ADS)

In three-dimensional disordered media, light localization can occur when the disorder is above a certain threshold. Researchers now report experimental evidence of this transition from light diffusion to trapping.

Conti, Claudio

2013-01-01

11

Anderson Localization in Disordered Vibrating Rods  

E-print Network

We study, both experimentally and numerically, the Anderson localization phenomenon in torsional waves of a disordered elastic rod, which consists of a cylinder with randomly spaced notches. We find that the normal-mode wave amplitudes are exponentially localized as occurs in disordered solids. The localization length is measured using these wave amplitudes and it is shown to decrease as a function of frequency. The normal-mode spectrum is also measured as well as computed, so its level statistics can be analyzed. Fitting the nearest-neighbor spacing distribution a level repulsion parameter is defined that also varies with frequency. The localization length can then be expressed as a function of the repulsion parameter. There exists a range in which the localization length is a linear function of the repulsion parameter, which is consistent with Random Matrix Theory. However, at low values of the repulsion parameter the linear dependence does not hold.

J. Flores; L. Gutiérrez; R. A. Méndez-Sánchez; G. Monsivais; P. Mora; A. Morales

2012-03-19

12

Anderson Localization in Disordered Vibrating Rods  

E-print Network

We study, both experimentally and numerically, the Anderson localization phenomenon in torsional waves of a disordered elastic rod, which consists of a cylinder with randomly spaced notches. We find that the normal-mode wave amplitudes are exponentially localized as occurs in disordered solids. The localization length is measured using these wave amplitudes and it is shown to decrease as a function of frequency. The normal-mode spectrum is also measured as well as computed, so its level statistics can be analyzed. Fitting the nearest-neighbor spacing distribution a level repulsion parameter is defined that also varies with frequency. The localization length can then be expressed as a function of the repulsion parameter. There exists a range in which the localization length is a linear function of the repulsion parameter, which is consistent with Random Matrix Theory. However, at low values of the repulsion parameter the linear dependence does not hold.

Flores, J; Méndez-Sánchez, R A; Monsivais, G; Mora, P; Morales, A

2012-01-01

13

Use of cluster computing for the Anderson model of localization  

NASA Astrophysics Data System (ADS)

We consider parallelization strategies for the two most frequently used algorithms in numerical investigations of the Anderson model of localization, a paradigmatic model of disordered quantum systems. After a brief review of the physics of Anderson localization, we discuss the application of the Cullum-Willoughby implementation of the Lanczos diagonalization scheme and the transfer-matrix method to massively parallel cluster architectures.

Cain, Philipp; Milde, Frank; Römer, Rudolf A.; Schreiber, Michael

2002-08-01

14

Microwave-Driven Atoms: From Anderson Localization to Einstein's Photoeffect  

SciTech Connect

We study the counterpart of Anderson localization in driven one-electron Rydberg atoms. By changing the initial Rydberg state at fixed microwave frequency and interaction time, we numerically monitor the crossover from Anderson localization to the photoeffect in the atomic ionization signal.

Schelle, Alexej [Physikalisches Institut der Albert-Ludwigs-Universitaet, Hermann-Herder-Strasse 3, D-79104 Freiburg (Germany); Laboratoire Kastler-Brossel, Universite Pierre et Marie Curie-Paris 6, ENS, CNRS, 4, Place Jussieu, F-75005 Paris (France); Delande, Dominique [Laboratoire Kastler-Brossel, Universite Pierre et Marie Curie-Paris 6, ENS, CNRS, 4, Place Jussieu, F-75005 Paris (France); Buchleitner, Andreas [Physikalisches Institut der Albert-Ludwigs-Universitaet, Hermann-Herder-Strasse 3, D-79104 Freiburg (Germany)

2009-05-08

15

Anderson localization of light near boundaries of disordered photonic lattices  

SciTech Connect

We study numerically the effect of boundaries on Anderson localization of light in truncated two-dimensional photonic lattices in a nonlinear medium. We demonstrate suppression of Anderson localization at the edges and corners, so that stronger disorder is needed near the boundaries to obtain the same localization as in the bulk. We find that the level of suppression depends on the location in the lattice (edge vs corner), as well as on the strength of disorder. We also discuss the effect of nonlinearity on various regimes of Anderson localization.

Jovic, Dragana M. [Institute of Physics, P. O. Box 57, 11001 Belgrade (Serbia); Texas A and M University at Qatar, P. O. Box 23874, Doha (Qatar); Kivshar, Yuri S. [Nonlinear Physics Center, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Denz, Cornelia [Institut fuer Angewandte Physik and Center for Nonlinear Science (CeNoS), Westfaelische Wilhelms-Universitaet Muenster, D-48149 Muenster (Germany); Belic, Milivoj R. [Texas A and M University at Qatar, P. O. Box 23874, Doha (Qatar)

2011-03-15

16

Observing transverse Anderson localization in random air line based fiber  

NASA Astrophysics Data System (ADS)

The concept of Anderson localization has been applied to electromagnetic waves for decades and strong photon localization effect has been observed in many two-dimensional systems including optical lattice and optical fibers. Among different types of optical fibers, both fibers with and without air hole were investigated. Air hole based fiber has significant higher refractive index contrast than other fibers which allow much lower filling fraction in order to observe Anderson localization. In a previous research, Anderson localization was observed near the fiber edge with an air fillfraction of 5.5%. At the fiber center region with only 2.2% air fill-fraction, Anderson localization disappeared. However, we observed Anderson localization in fibers with much lower air fill-fraction. In our experiments, random air line fibers with 150, 250 and 350 ?m diameters were fabricated and characterized by scanning electronic microscopy (SEM). Averaged air line diameters were 177, 247 and 387 nm for the 150, 250 and 350 ?m diameter fibers, respectively. Air fill-fraction was also measured at fiber center, middle and edge regions. Beam profiles were imaged into a charge couple device (CCD) and Anderson localization was observed. Unlike the previous research in which Anderson localization was only observed at the fiber edge due to non-uniform air line distribution, we observed Anderson localization within the fiber area with air fill-fraction significantly lower than the previous investigation. This is because with smaller air line diameter our fiber has higher air lines density than the previous report.

Chen, Minghan; Li, Ming-Jun

2014-02-01

17

Anderson localization of light: A little disorder is just right  

NASA Astrophysics Data System (ADS)

As with most things in life, some disorder can cause unexpected new phenomena. But when it comes to disorder-induced Anderson localization of light in a photonic crystal, simulations suggest that moderation may be the best policy.

López, Cefe

2008-10-01

18

Anderson localization in metamaterials and other complex media (Review Article)  

NASA Astrophysics Data System (ADS)

This is a review of some recent (mostly ours) results on Anderson localization of light and electron waves in complex disordered systems, including: (i) left-handed metamaterials, (ii) magnetoactive optical structures, (iii) graphene superlattices, and (iv) nonlinear dielectric media. First, we demonstrate that left-handed metamaterials can significantly suppress localization of light and lead to an anomalously enhanced transmission. This suppression is essential at the long-wavelength limit in the case of normal incidence, at specific angles of oblique incidence (Brewster anomaly), and in vicinity of zero-? or zero-? frequencies for dispersive metamaterials. Remarkably, in disordered samples comprised of alternating normal and left-handed metamaterials, the reciprocal Lyapunov exponent and reciprocal transmittance increment can differ from each other. Second, we study magnetoactive multilayered structures, which exhibit nonreciprocal localization of light depending on the direction of propagation and on polarization. At resonant frequencies or realizations such nonreciprocity results in effectively unidirectional transport of light. Third, we discuss the analogy between wave propagation through multilayered samples with metamaterials and charge transport in graphene, which provides a simple physical explanation of unusual conductive properties of disordered graphene superlatices. We predict disorder-induced resonance of the transmission coefficient at oblique incidence of Dirac quasiparticles. Finally, we demonstrate that an interplay of nonlinearity and disorder in dielectric media can lead to bistability of individual localized states excited inside the medium at resonant frequencies. This results in nonreciprocity of wave transmission and unidirectional transport of light.

Gredeskul, Sergey A.; Kivshar, Yuri S.; Asatryan, Ara A.; Bliokh, Konstantin Y.; Bliokh, Yuri P.; Freilikher, Valentin D.; Shadrivov, Ilya V.

2012-07-01

19

Anderson Localization for radial tree-like random quantum graphs  

E-print Network

We prove that certain random models associated with radial, tree-like, rooted quantum graphs exhibit Anderson localization at all energies. The two main examples are the random length model (RLM) and the random Kirchhoff model (RKM). In the RLM, the lengths of each generation of edges form a family of independent, identically distributed random variables (iid). For the RKM, the iid random variables are associated with each generation of vertices and moderate the current flow through the vertex. We consider extensions to various families of decorated graphs and prove stability of localization with respect to decoration. In particular, we prove Anderson localization for the random necklace model.

Peter D. Hislop; Olaf Post

2008-06-16

20

Anderson Localization Phenomenon in One-dimensional Elastic Systems  

E-print Network

The phenomenon of Anderson localization of waves in elastic systems is studied. We analyze this phenomenon in two different set of systems: disordered linear chains of harmonic oscillators and disordered rods which oscillate with torsional waves. The ?rst set is analyzed numerically whereas the second one is studied both experimentally and theoretically. In particular, we discuss the localization properties of the waves as a function of the frequency. In doing that we have used the inverse participation ratio, which is related to the localization length. We ?nd that the normal modes localize exponentially according to Anderson theory. In the elastic systems, the localization length decreases with frequency. This behavior is in contrast with what happens in analogous quantum mechanical systems, for which the localization length grows with energy. This difference is explained by means of the properties of the re ection coefficient of a single scatterer in each case.

Mendez-Sanchez, R A; Morales, A; Flores, J; Diaz-de-Anda, A; Monsivais, G

2013-01-01

21

Anderson localization and the theory of dirty superconductors  

NASA Technical Reports Server (NTRS)

A study is made of the effect of Anderson localization in dirty superconductors. The scale dependence of the diffusion in the vicinity of the mobility edge results in a strong renormalization of the zero-temperature coherence length. This implies the breakdown of the Ginzburg criterion close to the metal-insulator transition and thus the importance of fluctuations in this regime. The upper critical field is calculated, and possible experiments are also discussed.

Kapitulnik, A.; Kotliar, G.

1985-01-01

22

Dual landscapes in Anderson localization on discrete lattices  

NASA Astrophysics Data System (ADS)

The localization subregions of stationary waves in continuous disordered media have been recently demonstrated to be governed by a hidden landscape that is the solution of a Dirichlet problem expressed with the wave operator. In this theory, the strength of Anderson localization confinement is determined by this landscape, and continuously decreases as the energy increases. However, this picture has to be changed in discrete lattices in which the eigenmodes close to the edge of the first Brillouin zone are as localized as the low energy ones. Here we show that in a 1D discrete lattice, the localization of low and high energy modes is governed by two different landscapes, the high energy landscape being the solution of a dual Dirichlet problem deduced from the low energy one using the symmetries of the Hamiltonian. We illustrate this feature using the one-dimensional tight-binding Hamiltonian with random on-site potentials as a prototype model. Moreover we show that, besides unveiling the subregions of Anderson localization, these dual landscapes also provide an accurate overall estimate of the localization length over the energy spectrum, especially in the weak-disorder regime.

Lyra, M. L.; Mayboroda, S.; Filoche, M.

2015-02-01

23

Dual hidden landscapes in Anderson localization on discrete lattices  

E-print Network

The localization subregions of stationary waves in continuous disordered media have been recently demonstrated to be governed by a hidden landscape that is the solution of a Dirichlet problem expressed with the wave operator. In this theory, the strength of Anderson localization confinement is determined by this landscape, and continuously decreases as the energy increases. However, this picture has to be changed in discrete lattices in which the eigenmodes close to the edge of the first Brillouin zone are as localized as the low energy ones. Here we show that in a 1D discrete lattice, the localization of low and high energy modes is governed by two different landscapes, the high energy landscape being the solution of a dual Dirichlet problem deduced from the low energy one using the symmetries of the Hamiltonian. We illustrate this feature using the one-dimensional tight-binding Hamiltonian with random on-site potentials as a prototype model. Moreover we show that, besides unveiling the subregions of Anderson localization, these dual landscapes also provide an accurate overal estimate of the localization length over the energy spectrum, especially in the weak disorder regime.

Marcelo Leite Lyra; Svitlana Mayboroda; Marcel Filoche

2014-10-09

24

Transversal Anderson localization of sound in acoustic waveguide arrays.  

PubMed

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. PMID:25812602

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

2015-04-22

25

Strong coupling to two-dimensional Anderson localized modes.  

PubMed

We use a scattering formalism to derive a condition of strong coupling between a resonant scatterer and an Anderson localized mode for electromagnetic waves in two dimensions. The strong coupling regime is demonstrated based on exact numerical simulations, in perfect agreement with theory. The strong coupling threshold can be expressed in terms of the Thouless conductance and the Purcell factor. This connects key concepts in transport theory and cavity quantum electrodynamics, and provides a practical tool for the design or analysis of experiments. PMID:23952400

Cazé, A; Pierrat, R; Carminati, R

2013-08-01

26

Photon transport enhanced by transverse Anderson localization in disordered superlattices  

NASA Astrophysics Data System (ADS)

Controlling the flow of light at subwavelength scales provides access to functionalities such as negative or zero index of refraction, transformation optics, cloaking, metamaterials and slow light, but diffraction effects severely restrict our ability to control light on such scales. Here we report the photon transport and collimation enhanced by transverse Anderson localization in chip-scale dispersion-engineered anisotropic media. We demonstrate a photonic crystal superlattice structure in which diffraction is nearly completely arrested by cascaded resonant tunnelling through transverse guided resonances. By modifying the geometry of more than 4,000 scatterers in the superlattices we add structural disorder controllably and uncover the mechanism of disorder-induced transverse localization. Arrested spatial divergence is captured in the power-law scaling, along with exponential asymmetric mode profiles and enhanced collimation bandwidths for increasing disorder. With increasing disorder, we observe the crossover from cascaded guided resonances into the transverse localization regime, beyond both the ballistic and diffusive transport of photons.

Hsieh, P.; Chung, C.; McMillan, J. F.; Tsai, M.; Lu, M.; Panoiu, N. C.; Wong, C. W.

2015-03-01

27

Quantum resonance, Anderson localization, and selective manipulations in molecular mixtures by ultrashort laser pulses  

NASA Astrophysics Data System (ADS)

We show that the current laser technology used for field-free molecular alignment via impulsive Raman rotational excitation allows for observing long-discussed nonlinear quantum phenomena in the dynamics of the periodically kicked rotor. This includes the scaling of the absorbed energy near the conditions of quantum resonance and Anderson-like localization in the angular momentum. Based on this, we show that periodic trains of short laser pulses provide an efficient tool for selective rotational excitation and alignment in a molecular mixture. We demonstrate the efficiency of this approach by applying it to a mixture of two nitrogen isotopologues (14N2 and 15N2), and show that strong selectivity is possible even at room temperature.

Floß, Johannes; Averbukh, Ilya Sh.

2012-08-01

28

Topology versus Anderson localization: Nonperturbative solutions in one dimension  

NASA Astrophysics Data System (ADS)

We present an analytic theory of quantum criticality in quasi-one-dimensional topological Anderson insulators. We describe these systems in terms of two parameters (g ,? ) representing localization and topological properties, respectively. Certain critical values of ? (half-integer for Z classes, or zero for Z2 classes) define phase boundaries between distinct topological sectors. Upon increasing system size, the two parameters exhibit flow similar to the celebrated two-parameter flow of the integer quantum Hall insulator. However, unlike the quantum Hall system, an exact analytical description of the entire phase diagram can be given in terms of the transfer-matrix solution of corresponding supersymmetric nonlinear sigma models. In Z2 classes we uncover a hidden supersymmetry, present at the quantum critical point.

Altland, Alexander; Bagrets, Dmitry; Kamenev, Alex

2015-02-01

29

Applications of cluster computing for the Anderson model of localization  

E-print Network

systems. After a brief review of the physics of Anderson localiza- tion, we outline the Cullum-Willoughby algorithms considered, namely the Cullum-Willoughby version of the Lanczos method and the transfer

Chemnitz, Technische Universität

30

On fluctuations and localization length for the Anderson model on a strip  

E-print Network

We consider the Anderson model on a strip. Assuming that potentials have bounded density with considerable tails we get a lower bound for the fluctuations of the logarithm of the Green's function in a finite box. This implies an effective estimate by $ \\exp(CW^2) $ for the localization length of the Anderson model on the strip of width $ W $. The results are obtained, actually, for a more general model with a non-local operator in the vertical direction.

Ilia Binder; Michael Goldstein; Mircea Voda

2014-05-04

31

Beyond Anderson Localization in 1D: Anomalous Localization of Microwaves in Random Waveguides  

NASA Astrophysics Data System (ADS)

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 ? =1 /2 ("Lévy waveguides") and ? =3 /4 , ? 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.

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

2014-12-01

32

Wireless Sensor Network Localization Techniques Guoqiang Mao, Baris Fidan and Brian D.O. Anderson  

E-print Network

1 Wireless Sensor Network Localization Techniques Guoqiang Mao, Baris¸ Fidan and Brian D.O. Anderson Abstract-- Wireless sensor network localization is an important area that attracted significant on possible approaches to them. Index Terms-- wireless sensor networks, localization, AOA, RSS, TDOA. I

Scheuermann, Peter

33

PHYSICAL REVIEW A 83, 033813 (2011) Anderson localization of light near boundaries of disordered photonic lattices  

E-print Network

PHYSICAL REVIEW A 83, 033813 (2011) Anderson localization of light near boundaries of disordered distortion in the periodicity and induces the formation of localized surface states. One would expect that the presence of boundaries in random lattices would enhance the localization. However, a recent experimental

34

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

PubMed

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. PMID:24566557

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

2014-01-01

35

Example of self-averaging in three dimensions: Anderson localization of electromagnetic waves in random distributions of pointlike scatterers  

E-print Network

Example of self-averaging in three dimensions: Anderson localization of electromagnetic waves is used to study Anderson localization of electromagnetic waves in three-dimensional disordered dielectric of localized electromagnetic waves, emerging in the limit of an infinite system, is numerically observed. S1063

Rusek, Marian

36

Anderson localization in one-dimension with Levy-type disorder  

NASA Astrophysics Data System (ADS)

Abstract: Quantum transport through disordered systems has been the subject of extensive research since Anderson's seminal theory of localization. Motivated by experimental realizations of light transport across media exhibiting Levy-type fluctuations, we study the one-dimensional Anderson model where the random site energies are governed by a probability distribution with a broad tail, otherwise known as Levy-type. We numerically compute the Lyapunov exponent and its variance. This exponent is a self-averaging quantity whose inverse in certain cases can be used to define the localization length. Furthermore, we check for the validity of single parameter scaling (SPS), and its dependence on the Levy index.

Mayett, David; Schwarz, Jennifer

2013-03-01

37

Direct observation of Anderson localization of matter waves in a controlled disorder.  

PubMed

In 1958, Anderson predicted the localization of electronic wavefunctions in disordered crystals and the resulting absence of diffusion. It is now recognized that Anderson localization is ubiquitous in wave physics because it originates from the interference between multiple scattering paths. Experimentally, localization has been reported for light waves, microwaves, sound waves and electron gases. However, there has been no direct observation of exponential spatial localization of matter waves of any type. Here we observe exponential localization of a Bose-Einstein condensate released into a one-dimensional waveguide in the presence of a controlled disorder created by laser speckle. We operate in a regime of pure Anderson localization, that is, with weak disorder-such that localization results from many quantum reflections of low amplitude-and an atomic density low enough to render interactions negligible. We directly image the atomic density profiles as a function of time, and find that weak disorder can stop the expansion and lead to the formation of a stationary, exponentially localized wavefunction-a direct signature of Anderson localization. We extract the localization length by fitting the exponential wings of the profiles, and compare it to theoretical calculations. The power spectrum of the one-dimensional speckle potentials has a high spatial frequency cutoff, causing exponential localization to occur only when the de Broglie wavelengths of the atoms in the expanding condensate are greater than an effective mobility edge corresponding to that cutoff. In the opposite case, we find that the density profiles decay algebraically, as predicted in ref. 13. The method presented here can be extended to localization of atomic quantum gases in higher dimensions, and with controlled interactions. PMID:18548065

Billy, Juliette; Josse, Vincent; Zuo, Zhanchun; Bernard, Alain; Hambrecht, Ben; Lugan, Pierre; Clément, David; Sanchez-Palencia, Laurent; Bouyer, Philippe; Aspect, Alain

2008-06-12

38

Light focusing in the Anderson regime.  

PubMed

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. PMID:25072204

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

2014-01-01

39

Steady-state and dynamical Anderson localization of counterpropagating beams in two-dimensional photonic lattices  

SciTech Connect

We demonstrate Anderson localization of mutually incoherent counterpropagating beams in an optically induced two-dimensional photonic lattice. The effect is displayed in a system of two broad probe beams propagating head-on through a fixed disordered photonic lattice recorded in a photorefractive crystal. In addition to the steady-state localization, we also observe the dynamical localization; that is, the localization of time-changing beams. As compared to the localization of single beams, in which there exist no dynamical effects, the localization of counterpropagating beams is more pronounced and prone to instabilities.

Jovic, Dragana M. [Institute of Physics, P. O. Box 57, 11001 Belgrade (Serbia); Texas A and M University at Qatar, P. O. Box 23874, Doha (Qatar); Belic, Milivoj R. [Texas A and M University at Qatar, P. O. Box 23874, Doha (Qatar)

2010-02-15

40

Anderson Localization and Nonlinearity in One-Dimensional Disordered Photonic Lattices  

Microsoft Academic Search

We experimentally investigate the evolution of linear and nonlinear waves in a realization of the Anderson model using disordered one-dimensional waveguide lattices. Two types of localized eigenmodes, flat-phased and staggered, are directly measured. Nonlinear perturbations enhance localization in one type and induce delocalization in the other. In a complementary approach, we study the evolution on short time scales of delta-like

Yoav Lahini; Assaf Avidan; Francesca Pozzi; Marc Sorel; Roberto Morandotti; Demetrios N. Christodoulides; Yaron Silberberg

2008-01-01

41

Anderson localization and propagation of electromagnetic waves through disordered media  

Microsoft Academic Search

We have used the dynamic method to calculate the frequency dependence of the localization length in a disordered medium, using the amplitude change and the redshift of the spectral density of the propagating incident pulse. The frequency dependence of the localization length in an effectively one-dimensional disordered medium is computed in terms of the strength of the disorder. The results

A. Sheikhan; N. Abedpour; R. Sepehrinia; M. D. Niry; M. Reza Rahimi Tabar; M. Sahimi

2010-01-01

42

Anderson Localization for a Multi-Particle Quantum Graph  

NASA Astrophysics Data System (ADS)

We study a multi-particle quantum graph with random potential. Taking the approach of multiscale analysis, we prove exponential and strong dynamical localization of any order in the Hilbert-Schmidt norm near the spectral edge. Apart from the results on multi-particle systems, we also prove Lifshitz-type asymptotics for single-particle systems. This shows in particular that localization for single-particle quantum graphs holds under a weaker assumption on the random potential than previously known.

Sabri, Mostafa

2014-11-01

43

Anderson Localization of Expanding Bose-Einstein Condensates in Random Potentials  

Microsoft Academic Search

We show that the expansion of an initially confined interacting 1D Bose-Einstein condensate can exhibit Anderson localization in a weak random potential with correlation length sigmaR. For speckle potentials the Fourier transform of the correlation function vanishes for momenta k>2\\/sigmaR so that the Lyapunov exponent vanishes in the Born approximation for k>1\\/sigmaR. Then, for the initial healing length of the

Laurent Sanchez-Palencia; D. Clément; Pierre Lugan; Philippe Bouyer; Georgy V. Shlyapnikov; Alain Aspect

2007-01-01

44

Efficient localization bounds in a continuous multi-particle Anderson model with long-range interaction  

E-print Network

We establish strong dynamical localization for a class of multi-particle Anderson models in a Euclidean space with an alloy-type random potential and a sub-exponentially decaying interaction of infinite range. For the first time in the mathematical literature, the uniform decay bounds on the eigenfunction correlators at low energies are proved, in the multi-particle continuous configuration space, in the norm-distance and not in the Hausdorff pseudo-metric.

Victor Chulaevsky

2014-07-17

45

Scaling relations for local correlations during aging in an Edwards-Anderson spin glass  

NASA Astrophysics Data System (ADS)

We report results of a Monte Carlo study of the local correlations during aging of an Edwards-Anderson spin glass. We demonstrate that the local correlations are spatially inhomogeneous, but that their probability distribution function (PDF) has uniform behaviour that is determined by the ratio of the time to the waiting time. We find that the PDF obeys a scaling relation for different values of the time and waiting time that can be justified from a theory that is similar to that of fluctuating geometries or elasticity. We also investigate some of the fractal properties of local correlations and find an interesting correspondence with equilibrium results.

Kennett, Malcolm P.; Castillo, Horacio E.; Chamon, Claudio; Cugliandolo, Leticia F.

2002-03-01

46

Evolution of locally excited avalanches in semiconductors  

E-print Network

We show that semiconductor avalanche photodiodes can exhibit diminutive amplification noise during the early evolution of avalanches. The noise is so low that the number of locally excited charges that seed each avalanche can be resolved. These findings constitute an important first step towards realization of a solid-state noiseless amplifier. Moreover, we believe that the experimental setup used, \\textit{i.e.}, time-resolving locally excited avalanches, will become a useful tool for optimizing the number resolution.

Z. L. Yuan; J. F. Dynes; A. W. Sharpe; A. J. Shields

2010-05-25

47

Anderson localization of expanding Bose-Einstein condensates in random potentials.  

PubMed

We show that the expansion of an initially confined interacting 1D Bose-Einstein condensate can exhibit Anderson localization in a weak random potential with correlation length sigma(R). For speckle potentials the Fourier transform of the correlation function vanishes for momenta k>2/sigma(R) so that the Lyapunov exponent vanishes in the Born approximation for k>1/sigma(R). Then, for the initial healing length of the condensate xi(in)>sigma(R) the localization is exponential, and for xi(in)

Sanchez-Palencia, L; Clément, D; Lugan, P; Bouyer, P; Shlyapnikov, G V; Aspect, A

2007-05-25

48

Anderson Localization of Expanding Bose-Einstein Condensates in Random Potentials  

SciTech Connect

We show that the expansion of an initially confined interacting 1D Bose-Einstein condensate can exhibit Anderson localization in a weak random potential with correlation length {sigma}{sub R}. For speckle potentials the Fourier transform of the correlation function vanishes for momenta k>2/{sigma}{sub R} so that the Lyapunov exponent vanishes in the Born approximation for k>1/{sigma}{sub R}. Then, for the initial healing length of the condensate {xi}{sub in}>{sigma}{sub R} the localization is exponential, and for {xi}{sub in}<{sigma}{sub R} it changes to algebraic.

Sanchez-Palencia, L.; Clement, D.; Lugan, P.; Bouyer, P.; Aspect, A. [Laboratoire Charles Fabry de l'Institut d'Optique, CNRS and Univ. Paris-Sud, Campus Polytechnique, RD 128, F-91127 Palaiseau cedex (France); Shlyapnikov, G. V. [Laboratoire de Physique Theorique et Modeles Statistiques, Univ. Paris-Sud, F-91405 Orsay cedex (France); Van der Waals-Zeeman Institute, Univ. Amsterdam, Valckenierstraat 65/67, 1018 XE Amsterdam (Netherlands)

2007-05-25

49

Anderson Localization of Expanding Bose-Einstein Condensates in Random Potentials  

NASA Astrophysics Data System (ADS)

We show that the expansion of an initially confined interacting 1D Bose-Einstein condensate can exhibit Anderson localization in a weak random potential with correlation length ?R. For speckle potentials the Fourier transform of the correlation function vanishes for momenta k>2/?R so that the Lyapunov exponent vanishes in the Born approximation for k>1/?R. Then, for the initial healing length of the condensate ?in>?R the localization is exponential, and for ?in

Sanchez-Palencia, L.; Clément, D.; Lugan, P.; Bouyer, P.; Shlyapnikov, G. V.; Aspect, A.

2007-05-01

50

Self-Consistent Theory of Anderson Localization in Two Dimensions in View of Exact Transport Equation  

NASA Astrophysics Data System (ADS)

Self-consistent theory of Anderson localization of two-dimensional non-interacting electrons is formulated in the context of the exact transport equation and conductivity expression derived by the present authors (YI). The irreducible scattering vertex by Vollhardt and Wölfle (VW) is used in this equation, determining the diffusion coefficient in the scattering vertex self-consistently, through Einstein relation. It predicts a similar localization length to that obtained by VW, but shows that the conductivity evaluated by the Kubo formula decays exponentially, as the system size approaches the localization length. The result is opposed to the prediction by VW, who showed different behaviour of the diffusion coefficient that is equivalent to our conductivity. Our calculation also implies that the localization may be described along with the Landau-Silin theory of Fermi liquid.

Yamane, Y.; Itoh, M.

2012-10-01

51

Probing Anderson localization of light by weak non-linear effects  

NASA Astrophysics Data System (ADS)

Breakdown of wave transport due to strong disorder is a universal phenomenon known as Anderson localization (AL). It occurs because of the macroscopic population of reciprocal multiple scattering paths, which in three dimensional systems happens at a critical scattering strength. Intensities on these random loops should thus be highly increased relative to those of a diffusive sample. In order to highlight localized modes of light, we exploit the optical nonlinearities of TiO2. Power dependent and spectrally resolved time of flight distribution measurements in transmission through slabs of TiO2 powders at various turbidities reveal that mostly long loops are affected by nonlinearities and that the deviations from diffusive transport observed at long times are due to these localized modes. Our data are a first step in the experimental investigation of the interplay between nonlinear effects and AL in 3D.

Sperling, T.; Bührer, W.; Ackermann, M.; Aegerter, C. M.; Maret, G.

2014-11-01

52

Local structural excitations in model glasses  

NASA Astrophysics Data System (ADS)

Structural excitations of model Lennard-Jones glass systems are investigated using the activation-relaxation technique (ARTn), which explores the potential energy landscape around a local minimum energy configuration by converging to a nearby saddle-point configuration. Performing ARTn results in a distribution of barrier energies that is single-peaked for well-relaxed samples. The present work characterizes such atomic-scale excitations in terms of their local structure and environment. It is found that, at zero applied stress, many of the identified events consist of chainlike excitations that can either be extended or ringlike in their geometry. The location and barrier energy of these saddle-point structures are found to correlate with the type of atom involved, and with spatial regions that have low Kelvin eigenshear moduli and are close to the excess free volume within the configuration. Such correlations are, however, weak and more generally the identified local structural excitations are seen to exist throughout the model glass sample. The work concludes with a discussion within the framework of ? and ? relaxation processes that are known to occur in the undercooled liquid regime.

Swayamjyoti, S.; Löffler, J. F.; Derlet, P. M.

2014-06-01

53

Electronic states in the Anderson model of localization: benchmarking eigenvalue algorithms  

NASA Astrophysics Data System (ADS)

Multifractal analysis is a convenient tool to investigate localization properties of wavefunctions. For this purpose, eigenvectors for system sizes as large as possible are needed. We apply several modern eigenvalue algorithms to compute a few eigenvectors for the sparse, real, symmetric, and indefinite matrices of the Anderson model of localization in the band center. This seemingly innocuous problem turns out to be a major challenge for all modern eigenvalue algorithms, because we find the Lanczos implementation of Cullum and Willoughby to be the fastest and most memory efficient algorithm for our matrix type. It can, moreover, be effectively parallelized. Here, its results are used for the multifractal analysis, in particular to demonstrate that the singularity spectra of the wave functions do not depend on the system size at the metal-insulator transition.

Schreiber, Michael; Milde, Frank; Römer, Rudolf A.

1999-09-01

54

Nonreciprocal Anderson localization in one-dimensional ternary disordered media containing magnetized plasma layers  

NASA Astrophysics Data System (ADS)

This paper proposes a one-dimensional random structure composed of three types of alternating layers of dielectric and magnetized plasma materials. By employing the transfer matrix method, the localization lengths of the waves propagating in opposite directions are calculated. The numerical results demonstrate that nonreciprocal features appear in the averaged localization length and individual transmission resonances. However, in the short wavelength regime, the nonreciprocal behavior of the averaged localization length disappears, and the maximum of differential transmission decreases. The author investigates the effects of the external magnetic field, incident angle, collision frequency, and plasma density of the plasma layer on the reciprocal properties. The frequencies at which nonreciprocity occurs depend on the external magnetic field. Thus, it is possible to realize a photonic diode that is tunable with the external magnetic field. Also found is that for small angles of incidence no significant difference exists between the localization lengths of the forward and backward waves. There is a lower limit for the plasma density of the magnetized plasma layers to obtain nonreciprocal Anderson localization. As the collision frequency increases, the nonreciprocal features of the proposed random system survive.

Ghasempour Ardakani, Abbas

2014-06-01

55

Statistical measurements of quantum emitters coupled to Anderson-localized modes in disordered photonic-crystal waveguides  

NASA Astrophysics Data System (ADS)

Optical nanostructures have proven to be meritorious for tailoring the emission properties of quantum emitters. However, unavoidable fabrication imperfections may represent a nuisance. Quite remarkably, disorder offers new opportunities since light can be efficiently confined by random multiple scattering leading to Anderson localization. Here we investigate the effect of such disorder-induced cavities on the emission dynamics of single quantum dots embedded in disordered photonic-crystal waveguides. We present time-resolved measurements of both the total emission from Anderson-localized cavities and from single emitters that are coupled to the cavities. We observe both strongly inhibited and enhanced decay rates relative to the rate of spontaneous emission in a homogeneous medium. From a statistical analysis, we report an average Purcell factor of 2 in without any control on the quantum dot - cavity detuning. By spectrally tuning individual quantum dots into resonance with Anderson-localized modes, a maximum Purcell factor of 23.8 is recorded, which lies at the onset of the strong coupling regime. The presented data quantify the potential of naturally occurring Anderson-localized cavities for controlling and enhancing the light-matter interaction strength, which is of relevance not only for cavity quantum-electrodynamics experiments but potentially also for efficient energy harvesting and controllable random lasing.

Javadi, Alisa; Maibom, Sebastian; Sapienza, Luca; Thyrrestrup, Henri; García, Pedro D.; Lodahl, Peter

2014-12-01

56

A numerical study of wave-function and matrix-element statistics in the Anderson model of localization  

Microsoft Academic Search

We have calculated wave functions and matrix elements of the dipole operator in the two- and three-dimensional Anderson model of localization and have studied their statistical properties in the limit of weak disorder. In particular, we have considered two cases. First, we have studied the fluctuations as an external Aharonov-Bohm flux is varied. Second, we have considered the influence of

V. Uski; B. Mehlig; R. A. Römer

1998-01-01

57

Statistical measurements of quantum emitters coupled to Anderson-localized modes in disordered photonic-crystal waveguides.  

PubMed

We present a statistical study of the Purcell enhancement of the light emission from quantum dots coupled to Anderson-localized cavities formed in disordered photonic-crystal waveguides. We measure the time-resolved light emission from both single quantum emitters coupled to Anderson-localized cavities and directly from the cavities that are fed by multiple quantum dots. Strongly inhibited and enhanced decay rates are observed relative to the rate of spontaneous emission in a homogeneous medium. From a statistical analysis, we report an average Purcell factor of 4.5 ± 0.4 without applying any spectral tuning. By spectrally tuning individual quantum dots into resonance with Anderson-localized modes, a maximum Purcell factor of 23.8 ± 1.5 is recorded, which is at the onset of the strong-coupling regime. Our data quantify the potential of Anderson-localized cavities for controlling and enhancing the light-matter interaction strength in a photonic-crystal waveguide, which is of relevance for cavity quantum-electrodynamics experiments, efficient energy harvesting and random lasing. PMID:25607048

Javadi, Alisa; Maibom, Sebastian; Sapienza, Luca; Thyrrestrup, Henri; García, Pedro D; Lodahl, Peter

2014-12-15

58

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

SciTech Connect

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 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 another, much smaller characteristic length scale.

Kravtsov, V.E., E-mail: kravtsov@ictp.it [Abdus Salam International Centre for Theoretical Physics, P.O. Box 586, 34100 Trieste (Italy); Landau Institute for Theoretical Physics, 2 Kosygina st., 117940 Moscow (Russian Federation); Yudson, V.I., E-mail: yudson@isan.troitsk.ru [Institute for Spectroscopy, Russian Academy of Sciences, 142190 Troitsk, Moscow reg. (Russian Federation)

2011-07-15

59

Non-conventional Anderson localization in a matched quarter stack with metamaterials  

NASA Astrophysics Data System (ADS)

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 ?. In the limit ? ? 0 one gets a quite specific dependence, L-1loc??4?8, 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.

Torres-Herrera, E. J.; Izrailev, F. M.; Makarov, N. M.

2013-05-01

60

Energy level statistics at the metal-insulator transition in the Anderson model of localization with anisotropic hopping  

Microsoft Academic Search

Recently, a metal-insulator transition (MIT) was found in the anisotropic Anderson model of localization by transfer-matrix methods. This MIT has been also investigated by multifractal analysis and the same critical disorders Wc have been obtained within the accuracy of the data. We now employ energy level statistics to further characterize the MIT. We find a crossover of the nearest-neighbor level

F. Milde; R. A. Römer

1998-01-01

61

Characterization of nanoplasmonic structures by locally excited photoluminescence  

E-print Network

Characterization of nanoplasmonic structures by locally excited photoluminescence Alexandre pulses gives rise to photoluminescence mediated by two-photon absorption. A metal tip used to locally scatter the photoluminescence renders a map of regions with high field strengths. Near

Novotny, Lukas

62

Band of critical States in anderson localization in a strong magnetic field with random spin-orbit scattering.  

PubMed

The Anderson localization problem for a noninteracting two-dimensional electron gas subject to a strong magnetic field, disordered potential, and spin-orbit coupling is studied numerically on a square lattice. The nature of the corresponding localization-delocalization transition and the properties of the pertinent extended states depend on whether the spin-orbit coupling is uniform or fully random. For uniform spin-orbit coupling (such as Rashba coupling due to a uniform electric field), there is a band of metallic extended states in the center of a Landau band as in a "standard" Anderson metal-insulator transition. However, for fully random spin-orbit coupling, the familiar pattern of Landau bands disappears. Instead, there is a central band of critical states with definite fractal structure separated at two critical energies from two side bands of localized states. Moreover, finite size scaling analysis suggests that for this novel transition, on the localized side of a critical energy E_{c}, the localization length diverges as ?(E)?exp(?/sqrt[|E-E_{c}|]), a behavior which, together with the emergence of a band of critical states, is reminiscent of a Berezinskii-Kosterlitz-Thouless transition. PMID:25793840

Wang, C; Su, Ying; Avishai, Y; Meir, Yigal; Wang, X R

2015-03-01

63

Band of Critical States in Anderson Localization in a Strong Magnetic Field with Random Spin-Orbit Scattering  

NASA Astrophysics Data System (ADS)

The Anderson localization problem for a noninteracting two-dimensional electron gas subject to a strong magnetic field, disordered potential, and spin-orbit coupling is studied numerically on a square lattice. The nature of the corresponding localization-delocalization transition and the properties of the pertinent extended states depend on whether the spin-orbit coupling is uniform or fully random. For uniform spin-orbit coupling (such as Rashba coupling due to a uniform electric field), there is a band of metallic extended states in the center of a Landau band as in a "standard" Anderson metal-insulator transition. However, for fully random spin-orbit coupling, the familiar pattern of Landau bands disappears. Instead, there is a central band of critical states with definite fractal structure separated at two critical energies from two side bands of localized states. Moreover, finite size scaling analysis suggests that for this novel transition, on the localized side of a critical energy Ec, the localization length diverges as ? (E )?exp (? /?{|E -Ec| }), a behavior which, together with the emergence of a band of critical states, is reminiscent of a Berezinskii-Kosterlitz-Thouless transition.

Wang, C.; Su, Ying; Avishai, Y.; Meir, Yigal; Wang, X. R.

2015-03-01

64

Dual hidden landscapes in Anderson localization on discrete lattices Instituto de Fisica, Universidade Federal de Alagoas, 57072-970 Maceio, AL, Brazil  

E-print Network

Dual hidden landscapes in Anderson localization on discrete lattices M.L.Lyra Instituto de F in continuous disordered media have been recently demon- strated to be governed by a hidden landscape of the first Brillouin zone are as localized as the low energy ones. Here we show that in a 1D discrete lattice

Mayboroda, Svitlana

65

Statistics of renormalized on-site energies and renormalized hoppings for Anderson localization in two and three dimensions  

NASA Astrophysics Data System (ADS)

For Anderson localization models, there exists an exact real-space renormalization procedure at fixed energy which preserves the Green’s functions of the remaining sites [H. Aoki, J. Phys. C 13, 3369 (1980)]. Using this procedure for the Anderson tight-binding model in dimensions d=2,3 , we study numerically the statistical properties of the renormalized on-site energies ? and of the renormalized hoppings V as a function of the linear size L . We find that the renormalized on-site energies ? remain finite in the localized phase in d=2,3 and at criticality (d=3) , with a finite density at ?=0 and a power-law decay 1/?2 at large |?| . For the renormalized hoppings in the localized phase, we find: lnVL?-(L)/(?loc)+L?u , where ?loc is the localization length and u a random variable of order one. The exponent ? is the droplet exponent characterizing the strong disorder phase of the directed polymer in a random medium of dimension 1+(d-1) , with ?(d=2)=1/3 and ?(d=3)?0.24 . At criticality (d=3) , the statistics of renormalized hoppings V is multifractal, in direct correspondence with the multifractality of individual eigenstates and of two-point transmissions. In particular, we measure ?typ?1 for the exponent governing the typical decay lnVL¯?-?typlnL , in agreement with previous numerical measures of ?typ=d+?typ?4 for the singularity spectrum f(?) of individual eigenfunctions. We also present numerical results concerning critical surface properties.

Monthus, Cécile; Garel, Thomas

2009-07-01

66

Speaker Localization Using Excitation Source Information in Speech  

Microsoft Academic Search

This paper presents the results of simulation and real room studies for localization of a moving speaker using informa- tion about the excitation source of speech production. The first step in localization is the estimation of time-delay from speech collected by a pair of microphones. Methods for time-delay estimation gen- erally use spectral features that correspond mostly to the shape

Vikas C. Raykar; B. Yegnanarayana; S. R. Mahadeva Prasanna; Ramani Duraiswami

2005-01-01

67

Microwave conductance in random waveguides in the cross-over to Anderson localization and single-parameter scaling  

PubMed Central

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 ? 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

Shi, Zhou; Wang, Jing; Genack, Azriel Z.

2014-01-01

68

Quantum entanglement of localized excited states at finite temperature  

NASA Astrophysics Data System (ADS)

In this work we study the time evolutions of (Renyi) entanglement entropy of locally excited states in two dimensional conformal field theories (CFTs) at finite temperature. We consider excited states created by acting with local operators on thermal states and give both field theoretic and holographic calculations. In free field CFTs, we find that the growth of Renyi entanglement entropy at finite temperature is reduced compared to the zero temperature result by a small quantity proportional to the width of the localized excitations. On the other hand, in finite temperature CFTs with classical gravity duals, we find that the entanglement entropy approaches a characteristic value at late time. This behaviour does not occur at zero temperature. We also study the mutual information between the two CFTs in the thermofield double (TFD) formulation and give physical interpretations of our results.

Caputa, Pawel; Simón, Joan; Štikonas, Andrius; Takayanagi, Tadashi

2015-01-01

69

Suppress Winfree turbulence by local forcing excitable systems.  

PubMed

The occurrence of Winfree turbulence is currently regarded as one of the principal mechanisms underlying cardiac fibrillation. We develop a local stimulation method that suppresses Winfree turbulence in three-dimensional excitable media. We find that Winfree turbulence can be effectively suppressed by locally injecting periodic signals to only a very small subset (around some surface region) of total space sites. Our method for the first time demonstrates the effectiveness of local low-amplitude periodic excitations in suppressing turbulence in 3D excitable media and has fundamental improvements in efficiency, convenience, and turbulence suppression speed compared with previous strategies. Therefore, it has great potential for developing into a practical low-amplitude defibrillation approach. PMID:15904413

Zhang, Hong; Cao, Zhoujian; Wu, Ning-Jie; Ying, He-Ping; Hu, Gang

2005-05-13

70

Novel Localized Excitations of Nonlinear Coupled Scalar Fields  

NASA Astrophysics Data System (ADS)

Some extended solution mapping relations of the nonlinear coupled scalar field and the well-known phi4 model are presented. Simultaneously, inspired by the new solutions of the famous phi4 model recently proposed by Jia, Huang and Lou, five kinds of new localized excitations of the nonlinear coupled scalar field (NCSF) system are obtained.

Li, Jin-Hua; Wu, Huang-Jiao

2008-06-01

71

Enhanced Electromagnetic Chirality by Locally Excited Surface Plasmon Polaritons  

E-print Network

The possibility to enhance chiral light-matter interactions through plasmonic nanostructures provides entirely new opportunities for greatly improving the detection limits of chiroptical spectroscopies down to the single molecule level. The most pronounced of these chiral interactions occur in the ultraviolet (UV) range of the electromagnetic spectrum, which is difficult to access with conventional localized plasmon resonance based sensors. Although Surface Plasmon Polaritons (SPPs) on noble metal films can sustain resonances in the desired spectral range, their transverse magnetic nature has been an obstacle for enhancing chiroptical effects. Here we demonstrate, both analytically and numerically, that SPPs excited by near-field sources can exhibit rich and non-trivial chiral characteristics. In particular, we show that the excitation of SPPs by a chiral source not only results in a locally enhanced optical chirality but also achieves manifold enhancement of net optical chirality. Our finding that SPPs facil...

Alizadeh, M H

2015-01-01

72

Local and Regional Staging of Invasive Breast Cancer With Sonography: 25 Years of Practice at MD Anderson Cancer Center  

PubMed Central

At The University of Texas MD Anderson Cancer Center, we have used sonography (US) extensively for more than 2 decades to refine the local and regional staging of invasive breast cancer. Although magnetic resonance imaging is superior to all other imaging modalities in the measurement of the primary tumor and detection of additional foci of malignancy, in our experience US has shown sufficient accuracy in clinical practice to stage most invasive breast cancers. The exceptions are ill-defined tumors such as invasive lobular cancers and tumors in breasts containing extensive diffuse benign disease. An advantage of US is that multifocality or multicentricity can be confirmed via US-guided fine-needle aspiration within 15 minutes and the information shared immediately with the patient and the breast surgeon or medical oncologist. US has also proved indispensable in the evaluation of lymphatic spread because it can evaluate more nodal basins (e.g., the supraclavicular fossa and low neck) than magnetic resonance imaging can and because it can guide needle biopsy to confirm the status of any indeterminate node (including internal mammary nodes) within minutes. PMID:24309983

2014-01-01

73

Excited DeSitter brane worlds localized by a kink  

E-print Network

We reconsider, in five-dimensional space-time, the issue of thick brane localized in the extra dimension by a kink formed by a scalar field. The localization is achieved by a sine-Gordon potential. Apart from a fundamental brane (discovered by Koley and Kar \\cite{koley_kar}) where the scalar field is a monotonic function of the extra dimension), we show that a series of new solutions exist as well, labelled by the number of zeros of the scalar field. These solutions are regular, localized on the brane and mirror symmetric with respect to the extra dimension. They form a tower of "excited branes". The study of some perturbations of the solutions reveals that the new solutions are not stable. Finally, fermions are coupled to the scalar field by means of a Yukawa potential and their localization in the background of the new solutions is examined. %%The influence on the new solutions on the fermions on the brane is investigated. It turns out that the excited branes can localize left and right chiral fermion either on the brane and/or in the bulk but close to the brane.

Yves Brihaye; Térence Delsate

2012-04-27

74

PHYSICAL REVIEW B 85, 045122 (2012) Transmission and Anderson localization in dispersive metamaterials  

E-print Network

metamaterials Ara A. Asatryan,1 Lindsay C. Botten,1 Michael A. Byrne,1 Valentin D. Freilikher,2 Sergey A, one-dimensional stacks composed of dispersive metamaterials and normal materials are presented that the localization of waves in random stacks composed entirely of either metamaterial or normal dielectric layers

75

Anderson localization of matter waves in three-dimensional anisotropic disordered potentials  

NASA Astrophysics Data System (ADS)

Using a cutoff-free formulation of the coherent transport theory, we show that the interference terms at the origin of localization strongly affect the transport anisotropy. In contrast to the common hypothesis, we then find that the anisotropies of incoherent and coherent diffusion are significantly different, in particular at criticality. There, we show that the coherent transport anisotropy is mainly determined by the properties of the disorder-averaged effective scattering medium while the incoherent transport contributions become irrelevant.

Piraud, Marie; Sanchez-Palencia, Laurent; van Tiggelen, Bart

2014-12-01

76

Unusual magneto-optical behavior induced by local dielectric variations under localized surface plasmon excitations.  

PubMed

We study the effect of global and local dielectric variations on the polarization conversion rps response of ordered nickel nanowires embedded in an alumina matrix. When considering local changes, we observe a non-monotonous behavior of the rps, its intensity unusually modified far beyond to what it is expected for a monotonous change of the whole refractive index of the embedding medium. This is related to the local redistribution of the electromagnetic field when a localized surface plasmon is excited. This finding may be employed to develop and improve new biosensing magnetoplasmonic devices. PMID:21711939

González-Díaz, Juan B; García-Martín, Antonio; Reig, Gaspar Armelles

2011-01-01

77

Parametric excitation of multiple resonant radiations from localized wavepackets  

E-print Network

Fundamental physical phenomena such as laser-induced ionization, driven quantum tunneling, Faraday waves, Bogoliubov quasiparticle excitations, and the control of new states of matter rely on time-periodic driving of the system. A remarkable property of such driving is that it can induce the localized (bound) states to resonantly couple to the continuum. Therefore experiments that allow for enlightening and controlling the mechanisms underlying such coupling are of paramount importance. We implement such an experiment in a special fiber optics system characterized by a dispersion oscillating along the propagation coordinate, which mimics "time". The quasi-momentum associated with such periodic perturbation is responsible for the efficient coupling of energy from the localized wave-packets sustained by the fiber nonlinearity into free-running linear dispersive waves (continuum), at multiple resonant frequencies. Remarkably, the observed resonances can be explained by means of a unified approach, regardless of ...

Conforti, Matteo; Mussot, Arnaud; Kudlinski, Alexandre

2015-01-01

78

Variation of intermolecular interaction and local lattice distortion of parahydrogen crystals upon vibrational excitation  

Microsoft Academic Search

When a hydrogen molecule in a parahydrogen crystal is excited to a high vibrational overtone state, its electronic properties vary significantly since the energy of excitation is a sizable fraction of the energies of the excited electronic states. Thus the vibrational excitation leads to a significant variation of the intermolecular potential and resultant local distortion of the crystal lattice. Such

Robert M. Dickson; Takeshi Oka

1998-01-01

79

Parametric excitation of multiple resonant radiations from localized wavepackets.  

PubMed

Fundamental physical phenomena such as laser-induced ionization, driven quantum tunneling, Faraday waves, Bogoliubov quasiparticle excitations, and the control of new states of matter rely on time-periodic driving of the system. A remarkable property of such driving is that it can induce the localized (bound) states to resonantly couple to the continuum. Therefore experiments that allow for enlightening and controlling the mechanisms underlying such coupling are of paramount importance. We implement such an experiment in a special optical fiber characterized by a dispersion oscillating along the propagation coordinate, which mimics "time". The quasi-momentum associated with such periodic perturbation is responsible for the efficient coupling of energy from the localized wave-packets (solitons in anomalous dispersion and shock fronts in normal dispersion) sustained by the fiber nonlinearity, into free-running linear dispersive waves (continuum) at multiple resonant frequencies. Remarkably, the observed resonances can be explained by means of a unified approach, regardless of the fact that the localized state is a soliton-like pulse or a shock front. PMID:25801054

Conforti, Matteo; Trillo, Stefano; Mussot, Arnaud; Kudlinski, Alexandre

2015-01-01

80

Parametric excitation of multiple resonant radiations from localized wavepackets  

PubMed Central

Fundamental physical phenomena such as laser-induced ionization, driven quantum tunneling, Faraday waves, Bogoliubov quasiparticle excitations, and the control of new states of matter rely on time-periodic driving of the system. A remarkable property of such driving is that it can induce the localized (bound) states to resonantly couple to the continuum. Therefore experiments that allow for enlightening and controlling the mechanisms underlying such coupling are of paramount importance. We implement such an experiment in a special optical fiber characterized by a dispersion oscillating along the propagation coordinate, which mimics “time”. The quasi-momentum associated with such periodic perturbation is responsible for the efficient coupling of energy from the localized wave-packets (solitons in anomalous dispersion and shock fronts in normal dispersion) sustained by the fiber nonlinearity, into free-running linear dispersive waves (continuum) at multiple resonant frequencies. Remarkably, the observed resonances can be explained by means of a unified approach, regardless of the fact that the localized state is a soliton-like pulse or a shock front. PMID:25801054

Conforti, Matteo; Trillo, Stefano; Mussot, Arnaud; Kudlinski, Alexandre

2015-01-01

81

Localized nonlinear excitations in diffusive Hindmarsh-Rose neural networks  

NASA Astrophysics Data System (ADS)

We study localized nonlinear excitations in diffusive Hindmarsh-Rose neural networks. We show that the Hindmarsh-Rose model can be reduced to a modified Complex Ginzburg-Landau equation through the application of a perturbation technique. We equally report on the presence of envelop solitons of the nerve impulse in this neural network. From the biological point of view, this result suggests that neurons can participate in a collective processing of information, a relevant part of which is shared over all neurons but not concentrated at the single neuron level. By employing the standard linear stability analysis, the growth rate of the modulational instability is derived as a function of the wave number and systems parameters.

Moukam Kakmeni, F. M.; Inack, E. M.; Yamakou, E. M.

2014-05-01

82

The Anderson Current Loop  

NASA Technical Reports Server (NTRS)

Four-wire-probe concept applied to electrical-resistance transducers. Anderson current loop is excitation-and-signal-conditioning circuit suitable for use with strain gauges, resistance thermometers, and other electrical-resistance transducers mounted in harsh environments. Used as alternative to Wheatstone bridge. Simplifies signal-conditioning problem, enabling precise measurement of small changes in resistance of transducer. Eliminates some uncertainties in Wheatstone-bridge resistance-change measurements in flight research. Current loop configuration makes effects of lead-wire and contact resistances insignificantly small. Also provides output voltage that varies linearly with change in gauge resistance, and does so at double sensitivity of Wheatstone bridge.

Anderson, Karl F.

1994-01-01

83

Controlling the localization and migration of optical excitation  

NASA Astrophysics Data System (ADS)

In the nanoscale structure of a wide variety of material systems, a close juxtaposition of optically responsive components can lead to the absorption of light by one species producing fluorescence that is clearly attributable to another. The effect is generally evident in systems comprising two or more light-absorbing components (molecules, chromophores or quantum dots) with well-characterised fluorescence bands at similar, differentiable wavelengths. This enables the fluorescence associated with transferred energy to be discriminated against fluorescence from an initially excited component. The fundamental mechanism at the heart of the phenomenon, molecular (resonance) energy transfer, also operates in systems where the product of optical absorption is optical frequency up-conversion. In contrast to random media, structurally organised materials offer the possibility of pre-configured control over the delocalization of energy, through molecular energy transfer following optical excitation. The Förster mechanism that conveys energy between molecular-scale components is strongly sensitive to specific forms of correlation between the involved components, in terms of position, spectroscopic character, and orientation; one key factor is a spectroscopic gradient. Suitably designed materials offer a broad scope for the widespread exploitation of such features, in applications ranging from chemical and biological sensing to the detection of nanoscale motion or molecular conformations. Recently, attention has turned to the prospect of actively controlling the process of energy migration, for example by changing the relative efficiencies of fluorescence and molecular energy transfer. On application of static electric fields or off-resonant laser light - just two of the possibilities - each represents a means for achieving active control with ultrafast response, in suitably configured systems. As the principles are established and the theory is developed, a range of new possibilities for technical application is emerging. For example, applications can be envisaged for new forms of all-optical switching and transistor action. There is also interest in engaging with the interplay of optical excitation and local nanoscale force, exploiting local responses to changes in dispersion forces, accompanying molecular energy transfer.

Andrews, David L.; Bradshaw, David S.

2012-09-01

84

Localized excitations in (2+1)-dimensional systems.  

PubMed

By means of a special variable separation approach, a common formula with some arbitrary functions has been obtained for some suitable physical quantities of various (2+1)-dimensional models such as the Davey-Stewartson (DS) model, the Nizhnik-Novikov-Veselov (NNV) system, asymmetric NNV equation, asymmetric DS equation, dispersive long wave equation, Broer-Kaup-Kupershmidt system, long wave-short wave interaction model, Maccari system, and a general (N+M)-component Ablowitz-Kaup-Newell-Segur (AKNS) system. Selecting the arbitrary functions appropriately, one may obtain abundant stable localized interesting excitations such as the multidromions, lumps, ring soliton solutions, breathers, instantons, etc. It is shown that some types of lower dimensional chaotic patterns such as the chaotic-chaotic patterns, periodic-chaotic patterns, chaotic line soliton patterns, chaotic dromion patterns, fractal lump patterns, and fractal dromion patterns may be found in higher dimensional soliton systems. The interactions between the traveling ring type soliton solutions are completely elastic. The traveling ring solitons pass through each other and preserve their shapes, velocities, and phases. Some types of localized weak solutions, peakons, are also discussed. Especially, the interactions between two peakons are not completely elastic. After the interactions, the traveling peakons also pass through each other and preserve their velocities and phases, however, they completely exchange their shapes. PMID:12443343

Tang, Xiao-Yan; Lou, Sen-Yue; Zhang, Ying

2002-10-01

85

Localized excitations in (2+1)-dimensional systems  

NASA Astrophysics Data System (ADS)

By means of a special variable separation approach, a common formula with some arbitrary functions has been obtained for some suitable physical quantities of various (2+1)-dimensional models such as the Davey-Stewartson (DS) model, the Nizhnik-Novikov-Veselov (NNV) system, asymmetric NNV equation, asymmetric DS equation, dispersive long wave equation, Broer-Kaup-Kupershmidt system, long wave-short wave interaction model, Maccari system, and a general (N+M)-component Ablowitz-Kaup-Newell-Segur (AKNS) system. Selecting the arbitrary functions appropriately, one may obtain abundant stable localized interesting excitations such as the multidromions, lumps, ring soliton solutions, breathers, instantons, etc. It is shown that some types of lower dimensional chaotic patterns such as the chaotic-chaotic patterns, periodic-chaotic patterns, chaotic line soliton patterns, chaotic dromion patterns, fractal lump patterns, and fractal dromion patterns may be found in higher dimensional soliton systems. The interactions between the traveling ring type soliton solutions are completely elastic. The traveling ring solitons pass through each other and preserve their shapes, velocities, and phases. Some types of localized weak solutions, peakons, are also discussed. Especially, the interactions between two peakons are not completely elastic. After the interactions, the traveling peakons also pass through each other and preserve their velocities and phases, however, they completely exchange their shapes.

Tang, Xiao-Yan; Lou, Sen-Yue; Zhang, Ying

2002-10-01

86

Modeling of ion-acoustic soliton excitation through decay process of a localized perturbation  

Microsoft Academic Search

The possibility of the nonlinear decay of a localized perturbation into the ion-acoustic solitons is studied. The present paper is a theoretical attempt to model the experimental soliton excitation [S. Yi et al., Phys. Plasmas 4, 2436 (1997)] in which solitons are excited by a grid modulating near the ion plasma frequency. It has been reported that a localized wave

H. Hakimi Pajouh; H. Abbasi

2008-01-01

87

Jane Anderson: The Nazi Georgia Peach  

Microsoft Academic Search

The thrill-packed life of a little-known Georgian, Jane Anderson, proves that truth is stranger than fiction.\\u000aAnderson led an amazing life filled with exciting adventures, daring deeds, breathtaking escapades, and romantic interludes, a life stranger than the dreams of most people. She changed her name several times. She often traveled across the United States, and lived in Georgia, Arizona, Texas,

Wilkes Donald E. Jr

1995-01-01

88

Optical and magnetic signatures of localized excitations in polyaniline  

SciTech Connect

Using a tight-binding Hamiltonian we study the lattice configurations and electronic structures of three forms of polyaniline: leucoemeraldine base (LEB), emeraldine base (EB) and pernigraniline base (PNB). Both bond length and ring rotation angle are considered in the structure relaxation. The dominant elementary excitations of isolated chains are found to be solitons is PNB and bipolarons in EB and in LEB. Optical absorptions of the ground states and of the solitonic and polaronic excitations are calculated and compared with experiments. The spin density profile of a single neutral soliton in PNB is discussed in connection with magnetic measurements.

Su, W.P. (Houston Univ., TX (United States). Dept. of Physics Ohio State Univ., Columbus, OH (United States)); Epstein, A.J. (Ohio State Univ., Columbus, OH (United States)); Kim, J. (Houston Univ., TX (United States). Dept. of Physics)

1992-01-01

89

Optical and magnetic signatures of localized excitations in polyaniline  

SciTech Connect

Using a tight-binding Hamiltonian we study the lattice configurations and electronic structures of three forms of polyaniline: leucoemeraldine base (LEB), emeraldine base (EB) and pernigraniline base (PNB). Both bond length and ring rotation angle are considered in the structure relaxation. The dominant elementary excitations of isolated chains are found to be solitons is PNB and bipolarons in EB and in LEB. Optical absorptions of the ground states and of the solitonic and polaronic excitations are calculated and compared with experiments. The spin density profile of a single neutral soliton in PNB is discussed in connection with magnetic measurements.

Su, W.P. [Houston Univ., TX (United States). Dept. of Physics]|[Ohio State Univ., Columbus, OH (United States); Epstein, A.J. [Ohio State Univ., Columbus, OH (United States); Kim, J. [Houston Univ., TX (United States). Dept. of Physics

1992-10-01

90

Leona Anderson Oral History  

E-print Network

Oral history interview with Leona Anderson conducted by Rachel Gadd-Nelson in Burdick, Kansas, on September 18, 2009. In this interview, Leona Anderson discusses her experiences as a member of the Missouri Synod Lutheran ...

Anderson, Leona; Gadd-Nelson, Rachel

2009-09-18

91

Excitation by Local Electric Fields in the Aurora and Airglow  

Microsoft Academic Search

We have developed a method for accurate calculation of the distribution of electron energies in the ionosphere under the influence of an electric field. From this calculation we can predict rates of excitation of radiating states of N., O., and O as a function of the strength of a hypothetical applied field. We find that it is unreasonable to expect

L. R. Megill; N. P. Carleton

1964-01-01

92

State-selective optimization of local excited electronic states in extended systems  

NASA Astrophysics Data System (ADS)

Standard implementations of time-dependent density-functional theory (TDDFT) for the calculation of excitation energies give access to a number of the lowest-lying electronic excitations of a molecule under study. For extended systems, this can become cumbersome if a particular excited state is sought-after because many electronic transitions may be present. This often means that even for systems of moderate size, a multitude of excited states needs to be calculated to cover a certain energy range. Here, we present an algorithm for the selective determination of predefined excited electronic states in an extended system. A guess transition density in terms of orbital transitions has to be provided for the excitation that shall be optimized. The approach employs root-homing techniques together with iterative subspace diagonalization methods to optimize the electronic transition. We illustrate the advantages of this method for solvated molecules, core-excitations of metal complexes, and adsorbates at cluster surfaces. In particular, we study the local ? ??? excitation of a pyridine molecule adsorbed at a silver cluster. It is shown that the method works very efficiently even for high-lying excited states. We demonstrate that the assumption of a single, well-defined local excitation is, in general, not justified for extended systems, which can lead to root-switching during optimization. In those cases, the method can give important information about the spectral distribution of the orbital transition employed as a guess.

Kovyrshin, Arseny; Neugebauer, Johannes

2010-11-01

93

Sound Localization Based on Excitation Source Information for Intelligent Home Service Robots  

Microsoft Academic Search

\\u000a This paper is concerned with Sound Localization (SL) using Excitation Source Information (ESI) and effective angle estimation\\u000a for intelligent home service robots that are equipped with multi-channel sound board and three low-cost condenser microphones.\\u000a The main goal is to localize a caller by estimating time-delay with features obtained from the excitation source based on\\u000a Linear Prediction (LP) residual and Hilbert

Keun-chang Kwak

2008-01-01

94

Local Vibrational Excitation through Extended Electronic States at a Germanium Surface  

NASA Astrophysics Data System (ADS)

Atomic motion through excitation of extended surface electronic states on Ge(001) is studied using extraction of electrons by scanning tunneling microscopy and density functional theory. Single-electron excitation into the surface states nonlocally alters the tilting orientation of the surface Ge dimer, and the change rate depends on the excitation energy. Theoretical investigations identify the excited electronic states for the dimer motion, and clarify the strong coupling between the surface state electrons and a local vibrational mode of the dimer for changing the tilting orientation.

Tomatsu, Kota; Nakatsuji, Kan; Yamada, Masamichi; Komori, Fumio; Yan, Binghai; Yam, Chiyung; Frauenheim, Thomas; Xu, Yong; Duan, Wenhui

2009-12-01

95

Local excitations in thin metal films bounded by topological insulators  

NASA Astrophysics Data System (ADS)

Electromagnetic excitations arising in a metal slab surrounded by an insulator with a non-trivial topology associated to time reversal symmetry (topological insulator) are described. It is shown that the topological term induces modifications to the dispersion relations of bounding and antibounding surface modes in the long wavelength non-retarded limit which depend on the square of the topological term. In particular, it is shown that a backward wave arises with a group velocity undergoing a relative change which is independent of the film thickness. It is shown that the rotation of the polarization plane induced by the non-trivial topology is a linear function of the topological term for all slab thickness.

Granada E, J. C.; Rojas, D. F.

2014-12-01

96

Exact Three-Body Local Correlations for Excited States of the 1D Bose Gas  

SciTech Connect

We derive an exact analytic expression for the three-body local correlations in the Lieb-Liniger model of 1D Bose gas with contact repulsion. The local three-body correlations control the thermalization and particle loss rates in the presence of terms which break integrability, as is realized in the case of 1D ultracold bosons. Our result is valid not only at finite temperature but also for a large class of nonthermal excited states in the thermodynamic limit. We present finite temperature calculations in the presence of external harmonic confinement within local density approximation, and for a highly excited state that resembles an experimentally realized configuration.

Kormos, Marton; Chou Yangzhi; Imambekov, Adilet [Department of Physics and Astronomy, Rice University, Houston, Texas 77005 (United States)

2011-12-02

97

Anderson localization of cold atomic gases with effective spin-orbit interaction in a quasiperiodic optical lattice  

NASA Astrophysics Data System (ADS)

We theoretically investigate the localization properties of a spin-orbit-coupled spin-1/2 particle moving in a one-dimensional quasiperiodic potential, which can be experimentally implemented using cold atoms trapped in a quasiperiodic optical lattice potential and external laser fields. We present the phase diagram in the parameter space of the disorder strength and those related to the spin-orbit coupling. The phase diagram is verified via multifractal analysis of the atomic wave functions and the numerical simulation of diffusion dynamics. We found that spin-orbit coupling can lead to spectra mixing (coexistence of extended and localized states) and the appearance of mobility edges.

Zhou, Lu; Pu, Han; Zhang, Weiping

2013-02-01

98

Resonance enhancement of difference-frequency generation through localized surface plasmon excitation  

NASA Astrophysics Data System (ADS)

We report the experimental observation of difference-frequency generation in gold nanoparticles under localized surface plasmon excitation. A zero-delay peak is detected in the differential transmission signal for a gold nanoparticle film with a MgF2 overlayer, showing that the energy transfer from pump light to probe light through the difference-frequency generation is resonantly enhanced by the excitation. This peak of differential transmission decreases in strength with higher probe fluences. Both the enhancement and the power dependence of the difference-frequency generation are explained by modeling the localized surface plasmons as a nonlinear Lorentz resonator.

Fang, Xu; Yaginuma, Shin; Kubo, Wakana; Tanaka, Takuo

2013-05-01

99

Sound source localization with the aid of excitation source information in home robot environments  

Microsoft Academic Search

This paper is concerned with multiple microphone-based sound source localization in home robot environments. For this purpose, we use the excitation source information to determine the time-delay between each two microphones from speech source when robot's name is called. Furthermore, we present a novel method to estimate the reliable localization angle from the obtained time-delay values. Thus, it can be

Keun-Chang Kwak; Sung-Suk Kim

2008-01-01

100

J. Phys. Chem. B 1998, 102, 3310-3315 Localized Electronic Excitations in Phenylacetylene Dendrimers  

E-print Network

be used in the design of artificial Light harvesting antennae with controlled energy funneling path- ways optical excitation of conjugated dendrimers (fractal antenna macromolecules) are shown to be localized of phenylacetylene repeat unit in a self-similar fashion around the core (see Fig. 1). These macromolecules have been

Tretiak, Sergei

101

Excitations are localized and relaxation is hierarchical in glass-forming liquids  

E-print Network

For several atomistic models of glass formers, at conditions below their glassy dynamics onset temperatures, ${T_\\mathrm{o}}$, we use importance sampling of trajectory space to study the structure, statistics and dynamics of excitations responsible for structural relaxation. Excitations are detected in terms of persistent particle displacements of length $a$. At supercooled conditions, for $a$ of the order of or smaller than a particle diameter, we find that excitations are associated with correlated particle motions that are sparse and localized, occupying a volume with an average radius that is temperature independent and no larger than a few particle diameters. We show that the statistics and dynamics of these excitations are facilitated and hierarchical. Excitation energy scales grow logarithmically with $a$. Excitations at one point in space facilitate the birth and death of excitations at neighboring locations, and space-time excitation structures are microcosms of heterogeneous dynamics at larger scales. This nature of dynamics becomes increasingly dominant as temperature $T$ is lowered. We show that slowing of dynamics upon decreasing temperature below $T_\\mathrm{o}$ is the result of a decreasing concentration of excitations and concomitant growing hierarchical length scales, and further that the structural relaxation time $\\tau$ follows the parabolic law, $\\log(\\tau / \\tau_\\mathrm{o}) = J^2(1/T - 1/T_\\mathrm{o})^2$, for $T

Aaron S. Keys; Lester O. Hedges; Juan P. Garrahan; Sharon C. Glotzer; David Chandler

2014-05-07

102

Localized and propagating excitations in gapped phases of spin systems with bond disorder  

NASA Astrophysics Data System (ADS)

Using the conventional T-matrix approach, we discuss gapped phases in one-, two-, and three-dimensional (3D) spin systems (both with and without a long-range magnetic order) with bond disorder and with weakly interacting bosonic elementary excitations. This work is motivated by recent experimental and theoretical activity in spin-liquid-like systems with disorder and in the disordered interacting boson problem. In particular, we apply our theory to both paramagnetic low-field and fully polarized high-field phases in dimerized spin-1/2 systems and in integer-spin magnets with large single-ion easy-plane anisotropy D with disorder in exchange coupling constants (and/or D). The elementary excitation spectrum and the density of states are calculated in the first order in defects concentration c ?1. In 2D and 3D systems, the scattering on defects leads to a finite damping of all propagating excitations in the band except for states lying near its edges. We demonstrate that the analytical approach is inapplicable for states near the band edges and our numerical calculations reveal their localized nature. We find that the damping of propagating excitations can be much more pronounced in considered systems than in magnetically ordered gapless magnets with impurities. In 1D systems, the disorder leads to localization of all states in the band, while those lying far from the band edges (short-wavelength excitations) can look like conventional wave packets.

Utesov, O. I.; Sizanov, A. V.; Syromyatnikov, A. V.

2014-10-01

103

Local excitation of strongly coupled exciton-surface plasmons polaritons by a single nanoantenna  

SciTech Connect

We demonstrate experimentally local coupling of light from free space to exciton-surface plasmon polaritons (X-SPPs). This is achieved by using a single, sub-wavelength gold nanowire on top of a thin silver film which is covered with a 30?nm thick layer of J-aggregating dyes in polyvinyl alcohol. We show that the nanowire acts as an antenna that resonantly scatters light to X-SPPs states with a Rabi splitting of 0.1?eV. The locally excited X-SPPs properties are studied by angle resolved spectroscopy of the far-field leaky photons and are compared to the large-scale response through Kretschmann reflection measurements and to theoretical calculations. The nanowire scattering properties are studied by dark-field scattering measurements and finite-difference time-domain simulations. This method to locally excite X-SPPs can potentially be useful for future applications of hybrid light matter states.

Eizner, E., E-mail: eladeiz@post.tau.ac.il; Ellenbogen, T. [Department of Physical Electronics, Fleischman Faculty of Engineering, Tel Aviv University, Tel Aviv 69978 (Israel)

2014-06-02

104

Quantum walk and localization dynamics of rotational excitations in disordered ensembles of polar molecules  

E-print Network

We consider the dynamics of rotational excitations placed on a single molecule in spatially disordered 1D, 2D and 3D ensembles of ultracold molecules trapped in optical lattices. The disorder arises from incomplete populations of optical lattices with molecules. We show that for realistic experimental parameters this specific type of disorder leads to disorder-induced localization in 1D and 2D systems on a time scale $t \\sim 1$ sec. For 3D lattices with $55$ sites in each dimension and vacancy concentrations $\\leq 90 \\%$, the rotational excitations generated in the middle of the lattice diffuse to the edges of the lattice. We observe that the diffusion of rotational excitations in highly disordered 2D and 3D lattices has three distinct time scales. At short times, the rotational excitations diffuse as quantum particles expanding ballistically. At later times, the diffusion character changes to be the same as for the classical particles in Brownian motion. At still later times, the rotational excitations transition to a sub-diffusive regime. While the ballistic expansion is brief ($\\sim 10$ ms), the classical-like diffusion can last as long as 200-300 ms. We also examine the role of the long-range tunnelling amplitudes allowing for transfer of rotational excitations between distant lattice sites. Our results show that the long-range tunnelling has little impact on the dynamics in the diffusive regime but affects significantly the localization dynamics in lattices with large concentrations of vacancies, enhancing the width of the localized distributions in 2D lattices by more than a factor of 2.

Tianrui Xu; Roman V. Krems

2015-01-21

105

Effect of gold nanoparticles on the fluorescence excitation spectrum of ?-fetoprotein: Local environment dependent fluorescence quenching  

NASA Astrophysics Data System (ADS)

The effect of colloid gold nanoparticles (AuNPs) on the fluorescence excitation spectrum of ?-fetoprotein (AFP) has been investigated experimentally. The excitation spectral peaks of AFP with low concentration from 0.01 ng ml -1 to 12 ng ml -1 increase monotonically with increasing of AFP concentration. When some gold colloids were added to the AFP solution, the excitation peak at 285 nm decreases distinctly. By comparing the excitation peak intensity of AFP solution with gold colloids and without gold colloids at different AFP concentrations, the quenching effect from gold nanoparticle was more effective at lower AFP concentration. So the range of concentration from 0.01 ng ml -1 to 0.09 ng ml -1 will be the potential range of applications because of the higher sensitivity. The physical origin based on local field effect was investigated to illuminate this local environment dependent fluorescence quenching. The changing extent of quenching with different AFP concentrations can be attributed to the nonlinear decreasing of the local field factor of gold nanoparticles as a function of environmental dielectric constant.

Li, Jian-jun; Chen, Yu; Wang, A.-qing; Zhu, Jian; Zhao, Jun-wu

2011-01-01

106

Characterizing the Locality of Diabatic States for Electronic Excitation Transfer by Decomposing the Diabatic Coupling  

SciTech Connect

A common strategy to calculate electronic coupling matrix elements for charge or energy transfer is to take the adiabatic states generated by electronic structure computations and rotate them to form localized diabatic states. In this paper, we show that, for intermolecular transfer of singlet electronic excitation, usually we cannot fully localize the electronic excitations in this way. Instead, we calculate putative initial and final states with small excitation tails caused by weak interactions with high energy excited states in the electronic manifold. These tails do not lead to substantial changes in the total diabatic coupling between states, but they do lead to a different partitioning of the total coupling between Coulomb (Förster), exchange (Dexter), and one-electron components. The tails may be reduced by using a multistate diabatic model or eliminated entirely by truncation (denoted as “chopping”). Without more information, we are unable to conclude with certainty whether the observed diabatic tails are a physical reality or a computational artifact. This research suggests that decomposition of the diabatic coupling between chromophores into Coulomb, exchange, and one-electron components may depend strongly on the number of states considered, and such results should be treated with caution.

Vura-Weis, Josh; Newton, M. D.; Wasielewski, Michael R.; Subotnik, J. E.

2010-01-01

107

Non-Landau damping of magnetic excitations in systems with localized and itinerant electrons.  

PubMed

We discuss the form of the damping of magnetic excitations in a metal near a ferromagnetic instability. The paramagnon theory predicts that the damping term should have the form ?(q,?)??/?(q), with ?(q)?q (the Landau damping). However, the experiments on uranium metallic compounds UGe2 and UCoGe showed that ?(q) is essentially independent of q. A nonzero ?(q=0,?) is impossible in systems with one type of carrier (either localized or itinerant) because it would violate the spin conservation. It has been conjectured recently that a near-constant ?(q) in UGe2 and UCoGe may be due to the presence of both localized and itinerant electrons in these materials, with ferromagnetism involving predominantly localized spins. We present the microscopic analysis of the damping of near-critical localized excitations due to interaction with itinerant carriers. We show explicitly how the presence of two types of electrons breaks the cancellation between the contributions to ?(0) from the self-energy and vertex correction insertions into the spin polarization bubble. We compare our theory with the available experimental data. PMID:24484163

Chubukov, Andrey V; Betouras, Joseph J; Efremov, Dmitry V

2014-01-24

108

LES of a Jet Excited by the Localized Arc Filament Plasma Actuators  

NASA Technical Reports Server (NTRS)

The fluid dynamics of a high-speed jet are governed by the instability waves that form in the free-shear boundary layer of the jet. Jet excitation manipulates the growth and saturation of particular instability waves to control the unsteady flow structures that characterize the energy cascade in the jet.The results may include jet noise mitigation or a reduction in the infrared signature of the jet. The Localized Arc Filament Plasma Actuators (LAFPA) have demonstrated the ability to excite a high-speed jets in laboratory experiments. Extending and optimizing this excitation technology, however, is a complex process that will require many tests and trials. Computational simulations can play an important role in understanding and optimizing this actuator technology for real-world applications. Previous research has focused on developing a suitable actuator model and coupling it with the appropriate computational fluid dynamics (CFD) methods using two-dimensional spatial flow approximations. This work is now extended to three-dimensions (3-D) in space. The actuator model is adapted to a series of discrete actuators and a 3-D LES simulation of an excited jet is run. The results are used to study the fluid dynamics near the actuator and in the jet plume.

Brown, Clifford A.

2011-01-01

109

Relativistic Coulomb Excitation within the Time Dependent Superfluid Local Density Approximation  

NASA Astrophysics Data System (ADS)

Within the framework of the unrestricted time-dependent density functional theory, we present for the first time an analysis of the relativistic Coulomb excitation of the heavy deformed open shell nucleus 238U. The approach is based on the superfluid local density approximation formulated on a spatial lattice that can take into account coupling to the continuum, enabling self-consistent studies of superfluid dynamics of any nuclear shape. We compute the energy deposited in the target nucleus as a function of the impact parameter, finding it to be significantly larger than the estimate using the Goldhaber-Teller model. The isovector giant dipole resonance, the dipole pygmy resonance, and giant quadrupole modes are excited during the process. The one-body dissipation of collective dipole modes is shown to lead a damping width ???0.4 MeV and the number of preequilibrium neutrons emitted has been quantified.

Stetcu, I.; Bertulani, C. A.; Bulgac, A.; Magierski, P.; Roche, K. J.

2015-01-01

110

Temperature-Dependent Localized Excitations of Doped Carriers in Superconducting Diamond  

NASA Astrophysics Data System (ADS)

Laser-excited photoemission spectroscopy is used to show that the doped carriers in metallic or superconducting diamond couple strongly to the lattice via high-energy (˜150meV) optical phonons, with direct observations of localized Franck-Condon multiphonon sidebands appearing as Fermi-edge replicas. It exhibits a temperature-dependent spectral weight transfer from higher to lower energy sidebands and zero-phonon Fermi-edge states. The quantified coupling strength shows a systematic increase on lowering temperature, implicating its relation to the normal state transport and superconductivity.

Ishizaka, K.; Eguchi, R.; Tsuda, S.; Chainani, A.; Yokoya, T.; Kiss, T.; Shimojima, T.; Togashi, T.; Watanabe, S.; Chen, C.-T.; Takano, Y.; Nagao, M.; Sakaguchi, I.; Takenouchi, T.; Kawarada, H.; Shin, S.

2008-04-01

111

Bioinformatics Robert Anderson1  

E-print Network

Bioinformatics Robert Anderson1 and Zhiping Weng1,2 1. Bioinformatics Program 2. Department of Biomedical Engineering Boston University 44 Cummington Street Boston, MA 02215 What is Bioinformatics? Bioinformatics is the study of applying computational methods to large amount of biological information in order

Weng, Zhiping

112

Magnetic Excitations in the Nearly Localized, Itinerant Magnet Gd, Studied by Neutron Spectroscopy  

NASA Astrophysics Data System (ADS)

Many of the current questions about magnetic superconductors are present when these complex materials are in the normal state. Therefore studies of simpler itinerant magnets may help provide understanding of these phenomena. We chose to study an Itinerant magnet near to the fully localized limit. The system of choice, Gd has a total moment size of ˜7.6 ?B of which ˜0.6?B of that is itinerant. We used the SEQUOIA spectrometer, at the Spallation Neutron Source at Oak Ridge National Laboratory, to measure the magnetic excitations in a 12 gm ^160Gd single crystal. The fine resolution Fermi chopper was spun at 360 Hz and phased for Ei = 50 meV. The crystal was mounted with the h0l plane horizontal and then rotated around the vertical axis in 1^o steps. This method, and the large out of plane detector coverage of SEQUOIA, provided continuous coverage of a large region of reciprocal space allowing us to map the magnetic excitations. This map provides a measured structure factor for comparison to spin wave models with and without itinerancy effects. There measurements also more clearly resolve the excitations along the h00 direction than in previous studies (J. W. Cable, R. M. Nicklow and N. Wakabayashi Phys. Rev. B 32, 1710 (1985)).

Graroth, G. E.; Aczel, A. A.; Fernandez-Baca, J. A.; Nagler, S. E.

2012-02-01

113

Mechanisms of distributed and localized excitation of unsteady Görtler modes by free-stream vortices  

NASA Astrophysics Data System (ADS)

The present study is devoted to the investigation of several, presumably most efficient, mechanisms of the production of non-stationary Görtler vortices in a laminar boundary layer on a concave wall due to scattering of 2D and 3D free-stream vortices by streamwise localized 3D and 2D surface and flow non-uniformities. The experiments were carried out by means of the method of controllable non-stationary disturbances. The interaction of downstream-propagating 3D free-stream vortices with the growing boundary layer, presenting natural 2D bas-flow non-uniformity, was found to lead to a rather efficient excitation of unsteady Görtler modes. This mechanism of distributed receptivity is able to modify considerably the growth rates of the excited Görtler vortices in comparison with the linear stability laws. In the present paper, definitions of the coefficients of distributed vortical receptivity are given and some estimates of values of these coefficients are reported. In spite of a high measurement accuracy and a rather broad range of examined parameters, no excitation of Görtler vortices due to other examined mechanisms was identified.

Ivanov, A. V.; Kachanov, Y. S.; Mischenko, D. A.

2014-12-01

114

The Anderson Quin Cycle  

SciTech Connect

The objective of this study was to make a more refined evaluation of the Anderson Quin Cycle based on most recent information on the performance of various elements that will be used in the Anderson Quin Cycle. My original estimate of the work plan for evaluating and optimizing the Anderson Quin Cycle called for 7000 man hours of work. Since this grant was limited to 2150 man hours, we could not expect to achieve all the objectives within the allotted period of work. However, the most relevant program objectives have been completed as reported here. The analysis generally confirms the results originally estimated in my paper on the subject. (Ref. 2) Further optimizations should show even higher efficiencies. The Anderson Quin Cycle (US Patent applied for) basically consists of 5 elements in the power cycle: A refrigeration system to cool and clean the inlet air before it enters the compressor that supplies air for the gas turbine; a gas turbine consisting of a compressor, combustor, and turbine; a steam boiler and steam turbine system using the heat from the exhaust gas out of the gas turbine; a vapor turbine cycle, which utilizes the condensed heat from the exhaust of the steam turbine and the exhaust gas heat leaving the steam boiler to operate a vapor turbine cycle which utilizes another fluid than water, in this case isobutane; and the fifth element consists of a gas cooler and heat pump system, which removes the heat from the exhaust gas to lower its temperature essentially to atmospheric temperature, and at the same time permits treatment of the exhaust gas to remove acid components such as sulfur dioxide and nitrogen oxides. Current industry accepted component characteristics were incorporated in the performance analysis of the overall cycle, ensuring accurate and meaningful operating predictions. The characteristics and performance of each of the elements are described. The thermal efficiency of the optimized calculated Anderson Quin Cycle is 62 percent.

Anderson, J.H.; Bilbow, W.M.

1993-03-18

115

Acoustically Coupled Droplet Combustion and Local Extinction under High Amplitude Excitation  

NASA Astrophysics Data System (ADS)

The present experimental study examined the characteristics of liquid ethanol fuel droplet combustion in the presence of high amplitude acoustic excitation, with focus on conditions where high local flame strain can result in the periodic partial extinction and reignition within the flame front in time. These partial extinction phenomena were observed via phase-locked OH* chemiluminescence imaging and identified by the cycle of sudden, severe drop-off in chemiluminescent intensity near the flame stagnation region followed by reignition at the stagnation flame front at a later portion of the acoustic cycle. For increased excitation levels, the burning rate constant values were higher than those for both baseline quiescent and moderate excitation conditions. The experimental acoustic acceleration values were also higher than those for moderate excitation levels. Furthermore, as observed in past studies, these measurements of acoustic acceleration agreed only qualitatively with predictions from the acoustic radiation force theory. The presence of periodic partial extinction did not alter these expected trends. The temporal response in flame luminosity to flow perturbations was also analyzed using the Rayleigh index to determine the degree of thermoacoustic coupling inherent in a burning droplet system for given forcing conditions. When partial extinction was absent, the integrated OH* chemiluminescent intensity oscillated nearly in phase with the pressure perturbation. This led to a positive Rayleigh index, indicating unstable combustion, as was observed in previous studies at moderate excitation. However, partial extinction phenomena altered the relationship between measured intensity and pressure perturbations: the intensity oscillated nearly out of phase with the pressure perturbation. This led to a negative Rayleigh index, indicating stable combustion despite clear evidence of thermoacoustic coupling in the combustion footage and in the combustion property trends. These results indicated that the characterization of thermoacoustic coupling is important to the description of any droplet combustion system undergoing acoustic excitation; however, they also suggested that the Rayleigh index, at least when quantified using OH* chemiluminescence, may not fully capture the nature of thermoacoustic coupling in regimes where partial extinction phenomena occur.

Tran, Phuoc Hai Nguyen

116

Mean excitation energies for stopping powers in various materials using local plasma oscillator strengths  

NASA Technical Reports Server (NTRS)

The basic model of Lindhard and Scharff, known as the local plasma model, is used to study the effects on stopping power of the chemical and physical state of the medium. Unlike previous work with the local plasma model, in which individual electron shifts in the plasma frequency were estimated empirically, he Pines correction derived for a degenerate Fermi gas is shown herein to provide a reasonable estimate, even on the atomic scale. Thus, the model is moved to a complete theoretical base requiring no empirical adjustments, as characteristic of past applications. The principal remaining error is in the overestimation of the low-energy absorption properties that are characteristic of the plasma model in the region of the atomic discrete spectrum, although higher-energy phenomena are accurately represented, and even excitation-to-ionization ratios are given to fair accuracy. Mean excitation energies for covalent-bonded gases and solids, for ionic gases and crystals, and for metals are calculated using first-order models of the bonded states.

Wilson, J. W.; Xu, Y. J.; Kamaratos, E.; Chang, C. K.

1984-01-01

117

Localization of bleomycin in a single living cell using three-photon excitation microscopy  

NASA Astrophysics Data System (ADS)

Bleomycin has been used in the clinic as a chemotherapeutic agent for the treatment of several neoplasms, including non-Hodgkins lymphomas, squamous cell carcinomas, and testicular tumors. The effectiveness of bleomycin is believed to be derived from its ability to bind and oxidatively cleave DNA in the presence of a iron cofactor in vivo. A substantial amount of data on BLM has been collected, there is little information concerning the effects of bleomycin in living cells. In order to obtain data pertinent to the effects of BLM in intact cells, we have exploited the intrinsic fluorescence property of bleomycin to monitor the uptake of the drug in mammalian cells. We employed two light microscopy techniques, a wide-field and three-photon excitation (760 nm) fluorescence microscopy. Treatment of HeLa cells with bleomycin resulted in rapid to localization within the cells. In addition data collected from the wide field experiments, three-photon excitation of BLM which considerably reduced the phototoxic effect compared with UV light excitation in the wide-field microscopy indicated co-localization of the drug to regions of the cytoplasm occupied by the endoplasmic reticulum probe, DiOC5. The data clearly indicates that the cellular uptake of bleomycin after one minute includes the nucleus as well as in cytoplasm. Contrary to previous studies, which indicate chromosomal DNA as the target of bleomycin, the current findings suggest that the drug is distributed to many areas within the cell, including the endoplasmic reticulum, an organelle that is known to contain ribonucleic acids.

Abraham, Anil T.; Brautigan, David L.; Hecht, Sidney M.; Periasamy, Ammasi

2001-04-01

118

What underlies the Anderson Hamiltonian  

SciTech Connect

The Anderson Hamiltonian characterizes a model in which local orbitals interact with each other through Coulomb interactions and with a bath of itinerant states through hybridization. In trying to find a prescription for the parameters of the model, one simultaneously develops some understanding of the states involved and studies whether the model incorporates enough of the essential physics. One useful tactic is to compare this model with other models and ask how different effects are accommodated. This paper compares results from the model with atomic, band, and modified band calculations for f-electron materials. It did not appear to incorporate effects that seemed to be significant. Specifically, it is difficult to see the relation of this model to the multiple-screening-mode model which is a natural interpretation of our band calculations. The computations are represented as a surrogate for the experiment.

Koelling, D.D.

1986-10-01

119

How local excitation-inhibition ratio impacts the whole brain dynamics.  

PubMed

The spontaneous activity of the brain shows different features at different scales. On one hand, neuroimaging studies show that long-range correlations are highly structured in spatiotemporal patterns, known as resting-state networks, on the other hand, neurophysiological reports show that short-range correlations between neighboring neurons are low, despite a large amount of shared presynaptic inputs. Different dynamical mechanisms of local decorrelation have been proposed, among which is feedback inhibition. Here, we investigated the effect of locally regulating the feedback inhibition on the global dynamics of a large-scale brain model, in which the long-range connections are given by diffusion imaging data of human subjects. We used simulations and analytical methods to show that locally constraining the feedback inhibition to compensate for the excess of long-range excitatory connectivity, to preserve the asynchronous state, crucially changes the characteristics of the emergent resting and evoked activity. First, it significantly improves the model's prediction of the empirical human functional connectivity. Second, relaxing this constraint leads to an unrealistic network evoked activity, with systematic coactivation of cortical areas which are components of the default-mode network, whereas regulation of feedback inhibition prevents this. Finally, information theoretic analysis shows that regulation of the local feedback inhibition increases both the entropy and the Fisher information of the network evoked responses. Hence, it enhances the information capacity and the discrimination accuracy of the global network. In conclusion, the local excitation-inhibition ratio impacts the structure of the spontaneous activity and the information transmission at the large-scale brain level. PMID:24899711

Deco, Gustavo; Ponce-Alvarez, Adrián; Hagmann, Patric; Romani, Gian Luca; Mantini, Dante; Corbetta, Maurizio

2014-06-01

120

How Local Excitation–Inhibition Ratio Impacts the Whole Brain Dynamics  

PubMed Central

The spontaneous activity of the brain shows different features at different scales. On one hand, neuroimaging studies show that long-range correlations are highly structured in spatiotemporal patterns, known as resting-state networks, on the other hand, neurophysiological reports show that short-range correlations between neighboring neurons are low, despite a large amount of shared presynaptic inputs. Different dynamical mechanisms of local decorrelation have been proposed, among which is feedback inhibition. Here, we investigated the effect of locally regulating the feedback inhibition on the global dynamics of a large-scale brain model, in which the long-range connections are given by diffusion imaging data of human subjects. We used simulations and analytical methods to show that locally constraining the feedback inhibition to compensate for the excess of long-range excitatory connectivity, to preserve the asynchronous state, crucially changes the characteristics of the emergent resting and evoked activity. First, it significantly improves the model's prediction of the empirical human functional connectivity. Second, relaxing this constraint leads to an unrealistic network evoked activity, with systematic coactivation of cortical areas which are components of the default-mode network, whereas regulation of feedback inhibition prevents this. Finally, information theoretic analysis shows that regulation of the local feedback inhibition increases both the entropy and the Fisher information of the network evoked responses. Hence, it enhances the information capacity and the discrimination accuracy of the global network. In conclusion, the local excitation–inhibition ratio impacts the structure of the spontaneous activity and the information transmission at the large-scale brain level. PMID:24899711

Deco, Gustavo; Hagmann, Patric; Romani, Gian Luca; Mantini, Dante; Corbetta, Maurizio

2014-01-01

121

Locally-excited (LE) versus charge-transfer (CT) excited state competition in a series of para-substituted neutral green fluorescent protein (GFP) chromophore models.  

PubMed

In this paper, I provide a characterization of the low-energy electronic structure of a series of para-substituted neutral green fluorescent protein (GFP) chromophore models using a theoretical approach that blends linear free energy relationships (LFERs) with state-averaged complete-active-space self-consistent field (SA-CASSCF) theory. The substituents are chosen to sample the Hammett ?(p) scale from R = F to NH2, and a model of the neutral GFP chromophore structure (R = OH) is included. I analyze the electronic structure for different members of the series in a common complete-active-space valence-bond (CASVB) representation, exploiting an isolobal analogy between active-space orbitals for different members of the series. I find that the electronic structure of the lowest adiabatic excited state is a strong mixture of weakly coupled states with charge-transfer (CT) or locally excited (LE) character and that the dominant character changes as the series is traversed. Chromophores with strongly electron-donating substituents have a CT-like excited state such as expected for a push-pull polyene or asymmetric cyanine. Chromophores with weakly electron-donating (or electron-withdrawing) substituents have an LE-like excited state with an ionic biradicaloid structure localized to the ground-state bridge ? bond. PMID:25343562

Olsen, Seth

2015-02-12

122

Influence of local treatments of convection upon solar p mode excitation rates  

E-print Network

We compute the rates P at which acoustic energy is injected into the solar radial p modes for several solar models. The solar models are computed with two different local treatments of convection: the classical mixing-length theory (MLT hereafter) and Canuto et al (1996)'s formulation (CGM hereafter). Among the models investigated here, our best models reproduce both the solar radius and the solar luminosity at solar age and the observed Balmer line profiles. For the MLT treatment, the rates P do depend significantly on the properties of the atmosphere whereas for the CGM's treatment the dependence of P on the properties of the atmosphere is found smaller than the error bars attached to the seismic measurements. The excitation rates P for modes associated with the MLT models are significantly underestimated compared with the solar seismic constraints. The CGM models yield values for P closer to the seismic data than the MLT models. We conclude that the solar p-mode excitation rates provide valuable constraints and according to the present investigation clearly favor the CGM treatment with respect to the MLT, although neither of them yields values of P as close to the observations as recently found for 3D numerical simulations.

R. Samadi; F. Kupka; M. J. Goupil; Y. Lebreton; C. van't Veer-Menneret

2005-07-11

123

Localized Excitation in the Hybridization Gap in YbAl{sub 3}  

SciTech Connect

The intermediate valence compound YbAl{sub 3} exhibits a broad magnetic excitation in the inelastic neutron scattering spectrum with characteristic energy E{sub 1}{approx_equal}50 meV, equal to the Kondo energy (T{sub K}{approx}600-700 K). In the low temperature (Tlocalized excitation in the hybridization gap.

Christianson, A.D.; Fanelli, V.R. [University of California, Irvine, California 92697 (United States); Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Lawrence, J.M. [University of California, Irvine, California 92697 (United States); Goremychkin, E.A. [Argonne National Laboratory, Argonne, Illinois 60439 (United States); ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX (United Kingdom); Osborn, R. [Argonne National Laboratory, Argonne, Illinois 60439 (United States); Bauer, E.D.; Sarrao, J.L.; Thompson, J.D. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Frost, C.D. [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX (United Kingdom); Zarestky, J. L. [Ames Laboratory, Iowa State University, Ames, Iowa 50011 (United States)

2006-03-24

124

Natural triple excitations in local coupled cluster calculations with pair natural orbitals  

NASA Astrophysics Data System (ADS)

In this work, the extension of the previously developed domain based local pair-natural orbital (DLPNO) based singles- and doubles coupled cluster (DLPNO-CCSD) method to perturbatively include connected triple excitations is reported. The development is based on the concept of triples-natural orbitals that span the joint space of the three pair natural orbital (PNO) spaces of the three electron pairs that are involved in the calculation of a given triple-excitation contribution. The truncation error is very smooth and can be significantly reduced through extrapolation to the zero threshold. However, the extrapolation procedure does not improve relative energies. The overall computational effort of the method is asymptotically linear with the system size O(N). Actual linear scaling has been confirmed in test calculations on alkane chains. The accuracy of the DLPNO-CCSD(T) approximation relative to semicanonical CCSD(T0) is comparable to the previously developed DLPNO-CCSD method relative to canonical CCSD. Relative energies are predicted with an average error of approximately 0.5 kcal/mol for a challenging test set of medium sized organic molecules. The triples correction typically adds 30%-50% to the overall computation time. Thus, very large systems can be treated on the basis of the current implementation. In addition to the linear C150H302 (452 atoms, >8800 basis functions) we demonstrate the first CCSD(T) level calculation on an entire protein, Crambin with 644 atoms, and more than 6400 basis functions.

Riplinger, Christoph; Sandhoefer, Barbara; Hansen, Andreas; Neese, Frank

2013-10-01

125

Attraction of spiral waves by localized inhomogeneities with small-world connections in excitable media  

NASA Astrophysics Data System (ADS)

Trapping and untrapping of spiral tips in a two-dimensional homogeneous excitable medium with local small-world connections are studied by numerical simulation. In a homogeneous medium which can be simulated with a lattice of regular neighborhood connections, the spiral wave is in the meandering regime. When changing the topology of a small region from regular connections to small-world connections, the tip of the spiral waves is attracted by the small-world region, where the average path length declines with the introduction of long distant connections. The “trapped” phenomenon also occurs in regular lattices where the diffusion coefficient of the small region is increased. The above results can be explained by the eikonal equation, the Luther equation, and the relation between the core radius and the diffusion coefficient.

Wang, Xiaonan; Lu, Ying; Jiang, Minxi; Ouyang, Qi

2004-05-01

126

Head-on collisions of localized pressure excitations in derivative cubic relaxing media: dynamical structure survey  

NASA Astrophysics Data System (ADS)

In the wake of the recent derivation of the new cubic nonlinear evolution equation of high-frequency pressure perturbations of a barothropic medium under relaxation (Kuetche V K et al 2014 J. Math. Phys. 55 052702), we closely investigate the head-on collisions of some typical localized waveguide excitations, which are solutions to the previous system. From the viewpoint of Hirota?s formalism, we delve into the structural scattering features of the interacting waves mentioned above. As a result, we find that there might exist some ‘characteristic’ amplitude ratio of the interacting waves at which the scattering changes its features. Accordingly, we provide an illustration of the previous result within the depiction of the interactions between three single soliton solutions alongside the phase-shift of each particle. Following these depictions, we address some physical implications of the results as well as the different potential applications.

Youssoufa, Saliou; Kamgang Kuetche, Victor; Crepin Kofane, Timoleon

2015-02-01

127

Tracking hole localization in K -shell and core-valence-excited acetylene photoionization via body-frame photoelectron angular distributions  

NASA Astrophysics Data System (ADS)

Asymmetry in the molecular-frame photoelectron angular distributions from core-hole- or core-valence-excited polyatomic targets with symmetry-equivalent atoms can provide direct evidence for core-hole localization. Using acetylene as an example, we contrast the small asymmetry that can be seen in direct core-level ionization, due to the competition between two competing pathways to the continuum, with ionization from core-valence-excited HCCH, which offers the prospect of observing markedly greater asymmetry.

Rescigno, T. N.; Trevisan, C. S.; McCurdy, C. W.

2015-02-01

128

Talmadge Anderson Heritage House Talmadge Anderson Heritage House  

E-print Network

Talmadge Anderson Heritage House Talmadge Anderson Heritage House 935 NE B Street, Pullman, WA and Heritage Houses: 509-339-6172 or marc_robinson@wsu.edu. 2. The WSU Culture and Heritage Houses are open present at the event. 4. All events must have a Cultural House Assistant on hand. The Office of Equity

Collins, Gary S.

129

Effect of gold nanoparticles on the fluorescence excitation spectrum of ?-fetoprotein: Local environment dependent fluorescence quenching  

Microsoft Academic Search

The effect of colloid gold nanoparticles (AuNPs) on the fluorescence excitation spectrum of ?-fetoprotein (AFP) has been investigated experimentally. The excitation spectral peaks of AFP with low concentration from 0.01ngml?1 to 12ngml?1 increase monotonically with increasing of AFP concentration. When some gold colloids were added to the AFP solution, the excitation peak at 285nm decreases distinctly. By comparing the excitation

Jian-jun Li; Yu Chen; A-qing Wang; Jian Zhu; Jun-wu Zhao

2011-01-01

130

America's First Illustrator: Alexander Anderson  

NSDL National Science Digital Library

The New York Public Library presents this digital edition of the scrapbooks of 19th-century master illustrator Alexander Anderson. During his 70-year career, Anderson (1775-1870) created wood engravings to illustrate books, periodicals, newspapers, broadsides, and posters, based on his own designs, and the work of other artists. Some of the more prominent works illustrated by Anderson include John Bunyan's "Pilgrim's Progress", O.L. Holley's "Life of Benjamin Franklin", surveys of architecture, and books intended for teaching school children. This digital collection contains 1,332 of Anderson's engravings that can be browsed or searched by subject. To help interested users determine where images in the scrapbooks may have been published, titles of several major printed catalogs of Anderson's work are listed on the collection guide.

131

Local CC2 response method based on the Laplace transform: Orbital-relaxed first-order properties for excited states  

NASA Astrophysics Data System (ADS)

A multistate local CC2 response method for the calculation of orbital-relaxed first order properties is presented for ground and electronically excited states. It enables the treatment of excited state properties including orbital relaxation for extended molecular systems and is a major step on the way towards analytic gradients with respect to nuclear displacements. The Laplace transform method is employed to partition the eigenvalue problem and the lambda equations, i.e., the doubles parts of these equations are inverted on-the-fly, leaving only the corresponding effective singles equations to be solved iteratively. Furthermore, the state specific local approximations are adaptive. Density-fitting is utilized to decompose the electron-repulsion integrals. The accuracy of the local approximation is tested and the efficiency of the new code is demonstrated on the example of an organic sensitizer for solar-cell applications, which consists of about 100 atoms.

Ledermüller, Katrin; Kats, Daniel; Schütz, Martin

2013-08-01

132

How Large is Large? Estimating the Critical Disorder for the Anderson Model  

NASA Astrophysics Data System (ADS)

Complete localization is shown to hold for the d-dimensional Anderson model with uniformly distributed random potentials provided the disorder strength where satisfies with the self-avoiding walk connective constant for the lattice . Notably, is precisely the large disorder threshold proposed by Anderson in 1958.

Schenker, Jeffrey

2015-01-01

133

Anderson Localization of a non-interacting Bose-Einstein condensate with effective spin-orbit interaction in a quasiperiodic optical lattice  

NASA Astrophysics Data System (ADS)

We theoretically investigate the localization properties of a noninteracting atomic Bose-Einstein condensate moving in a one-dimensional quasiperiodic optical lattice potential in the tight-binding regime. The atoms are subject to effective spin-orbit coupling induced by external laser fields. We present the phase diagram in the parameter space of the disorder strength and those related to the effective spin-orbit coupling. The phase diagram are verified via multifractal analysis of the atomic wavefunctions. We found that spin-orbit coupling can lead to the spectra mixing (coexistence of extended and localized states) and the appearance of mobility edges.

Zhou, Lu; Pu, Han; Zhang, Weiping

2013-03-01

134

Novel variable separation solutions and exotic localized excitations via the ETM in nonlinear soliton systems  

NASA Astrophysics Data System (ADS)

In this paper, first, the ETM is applied to obtain variable separation solutions of (2+1)-dimensional systems. A common formula with some arbitrary functions is derived to describe suitable physical quantities for some (2+1)-dimensional models such as the generalized Nizhnik-Novikov-Veselov, Davey-Stewartson, Broer-Kaup-Kupershmidt, Boiti-Leon-Pempinelli, integrable Kortweg-de Vries (KdV), breaking soliton and Burgers models. The universal formula in Tang, Lou, and Zhang [Phys. Rev. E 66, 046601 (2002)] can be simplified to the common formula in the present paper, which indicates that redundant process is included there since the easier variable separation form can be employed without loss of generality. Second, this method is successfully generalized to (1+1)-dimensional systems, such as coupled integrable dispersionless, long-wave-short-wave resonance interaction and negative KdV models, and obtain another common formula to describe suitable physical fields or potentials of these (1+1)-dimensional models, which is similar to the one in (2+1)-dimensional systems. Moreover, it also is extended to (3+1)-dimensional Burgers system, and find that the common formula in (2+1)-dimensional systems is also appropriate to describe the (3+1)-dimensional Burgers system. The only differences are that the function q is a solution of a constraint equation and p is an arbitrary function of three independent variables. Finally, based on the common formula for (2+1)-dimensional systems and by selecting appropriate multivalued functions, interactions among special dromion, special peakon and foldon are investigated. The interactions between two special dromions, and between two special peakons, both possess novel properties, that is, there exist a multivalued foldon in the process of their collision, which is different from the reported cases in previous literature. Furthermore, the explicit phase shifts for all the local excitations offered by the common formula have been given, and are applied to these novel interactions in detail.

Dai, Chao-qing; Zhang, Jie-fang

2006-04-01

135

Anderson transition for Google matrix eigenstates  

E-print Network

We introduce a number of random matrix models describing the Google matrix G of directed networks. The properties of their spectra and eigenstates are analyzed by numerical matrix diagonalization. We show that for certain models it is possible to have an algebraic decay of PageRank vector with the exponent similar to real directed networks. At the same time the spectrum has no spectral gap and a broad distribution of eigenvalues in the complex plain. The eigenstates of G are characterized by the Anderson transition from localized to delocalized states and a mobility edge curve in the complex plane of eigenvalues.

Zhirov, O V

2015-01-01

136

Characterizing the Locality of Diabatic States forElectronic Excitation Transfer By Decomposing theDiabatic Coupling  

SciTech Connect

A common strategy to calculate electronic coupling matrix elements for charge or energy transfer is to take the adiabatic states generated by electronic structure computations and rotate them to form localized diabatic states. In this paper, we show that, for intermolecular transfer of singlet electronic excitation, usually we cannot fully localize the electronic excitations in this way. Instead, we calculate putative initial and final states with small excitation tails caused by weak interactions with high energy excited states in the electronic manifold. These tails do not lead to substantial changes in the total diabatic coupling between states, but they do lead to a different partitioning of the total coupling between Coulomb (Forster), exchange (Dexter), and one-electron components. The tails may be reduced by using a multistate diabatic model or eliminated entirely by truncation (denoted as 'chopping'). Without more information, we are unable to conclude with certainty whether the observed diabatic tails are a physical reality or a computational artifact. This research suggests that decomposition of the diabatic coupling between chromophores into Coulomb, exchange, and one-electron components may depend strongly on the number of states considered, and such results should be treated with caution.

Newton, M.D.; Vura-Weis, J.; Wasielewski, M.R.; Subotnik, J.E.

2010-10-19

137

High pressure luminescence studies of localized excitations in ZnS doped with Pb2+ and Mn2+  

Microsoft Academic Search

High pressure luminescence measurements have been made on ZnS doped with Pb+2 and Mn+2. The data include changes in peak energy and shape, integrated intensities, and lifetimes. These localized emissions are treated in terms of a single configuration coordinate model. For Pb+2 the emission peak shifted to lower energy by a moderate amount and narrowed. For excitation in the Pb+2

G. L. House; H. G. Drickamer

1977-01-01

138

Predicting Accurate Electronic Excitation Transfer Rates via Marcus Theory with Boys or Edmiston-Ruedenberg Localized Diabatization  

PubMed Central

We model the triplet-triplet energy transfer experiments from the Closs group [G. L. Closs et al, JACS, 110, p. 2652 (1988)] using a combination of Marcus theory and either Boys or Edmiston-Ruedenberg localized diabatization. We show that relative and absolute rates of electronic excitation transfer may be computed successfully, as we find ?calc = 2.8 per C-C bond, compared with the experimental value ?exp = 2.6, for the case where both donor and acceptor occupy equatorial positions on a rigid cyclohexane bridge. This work highlights the power of using localized diabatization methods as a tool for modeling non-equilibrium processes. PMID:20446743

Sodt, Alex J.; Ratner, Mark A.

2010-01-01

139

Periodic Anderson model for four-site clusters  

Microsoft Academic Search

The periodic Anderson model is applied to three different four-site clusters (square, rhombus, and tetrahedron) with periodic boundary conditions. We consider one extended orbital per site per spin with an interatomic transfer integral t and with the mean energy chosen to be zero. We also consider one localized f orbital per site per spin with energy Ef with a Coulomb

P. K. Misra; D. G. Kanhere; Joseph Callaway

1987-01-01

140

Self-consistent band calculations for an Anderson Hamiltonian treatment of anisotropic f-electron systems  

NASA Astrophysics Data System (ADS)

The unusual magnetic ordering, magnetic excitation behavior, and anomalous crystal-field splitting in CeBi and CeSb can be explained using a model Hamiltonian obtained by applying the Schrieffer-Wolff transformation to the Anderson Hamiltonian. It is highly desirable to obtain a first principles prediction of the parameters of the theory in order to extend this understanding quantitatively to other cerium and light actinide materials. To this end, we have calculated the electronic structure of CeBi and CeSb with the linear muffin-tin orbital (LMTO) method, using a self-consistent fully warped potential, and have obtained the coupling between non-f band states and f states localized in the sense of the Anderson Hamiltonian. This is applied to a calculation of the anomalous crystal-field splitting in CeBi and CeSb, and application to calculating the anisotropic two-ion interaction is discussed. We find that the dominant contribution to the anomalous crystal-field effect (about two thirds) comes from hybridization with d bands.

Wills, J. M.; Cooper, B. R.; Thayamballi, P.

1985-04-01

141

Describing excited state relaxation and localization in TiO2 nanoparticles using TD-DFT  

SciTech Connect

We have investigated the description of excited state relaxation in naked and hydrated TiO2 nanoparticles using Time-Dependent Density Functional Theory (TD-DFT) with three common hybrid exchange-correlation (XC) potentials; B3LYP, CAM-B3LYP and BHLYP. Use of TD-CAM-B3LYP and TD-BHLYP yields qualitatively similar results for all structures, which are also consistent with predictions of coupled cluster theory for small particles. TD-B3LYP, in contrast, is found to make rather different predictions; including apparent conical intersections for certain particles that are not observed with TD-CAM-B3LYP nor with TD-BHLYP. In line with our previous observations for vertical excitations, the issue with TD-B3LYP appears to be the inherent tendency of TD-B3LYP, and other XC potentials with no or a low percentage of Hartree-Fock Like Exchange, to spuriously stabilize the energy of charge-transfer (CT) states. Even in the case of hydrated particles, for which vertical excitations are generally well described with all XC potentials, the use of TD-B3LYP appears to result in CT-problems for certain particles. We hypothesize that the spurious stabilization of CT-states by TD-B3LYP even may drive the excited state optimizations to different excited state geometries than those obtained using TD-CAM-B3LYP or TD-BHLYP. Finally, focusing on the TD-CAM-B3LYP and TD-BHLYP results, excited state relaxation in naked and hydrated TiO2 nanoparticles is predicted to be associated with a large Stokes’ shift.

Berardo, Enrico; Hu, Hanshi; van Dam, Hubertus JJ; Shevlin, S. A.; Woodley, Scott M.; Kowalski, Karol; Zwijnenburg, Martijn A.

2014-10-30

142

Probing local bias-induced transitions using photothermal excitation contact resonance atomic force microscopy and voltage spectroscopy.  

PubMed

Nanomechanical properties are closely related to the states of matter, including chemical composition, crystal structure, mesoscopic domain configuration, etc. Investigation of these properties at the nanoscale requires not only static imaging methods, e.g., contact resonance atomic force microscopy (CR-AFM), but also spectroscopic methods capable of revealing their dependence on various external stimuli. Here we demonstrate the voltage spectroscopy of CR-AFM, which was realized by combining photothermal excitation (as opposed to the conventional piezoacoustic excitation method) with the band excitation technique. We applied this spectroscopy to explore local bias-induced phenomena ranging from purely physical to surface electromechanical and electrochemical processes. Our measurements show that the changes in the surface properties associated with these bias-induced transitions can be accurately assessed in a fast and dynamic manner, using resonance frequency as a signature. With many of the advantages offered by photothermal excitation, contact resonance voltage spectroscopy not only is expected to find applications in a broader field of nanoscience but also will provide a basis for future development of other nanoscale elastic spectroscopies. PMID:25559112

Li, Qian; Jesse, Stephen; Tselev, Alexander; Collins, Liam; Yu, Pu; Kravchenko, Ivan; Kalinin, Sergei V; Balke, Nina

2015-02-24

143

Local CC2 response method based on the Laplace transform: Analytic energy gradients for ground and excited states  

SciTech Connect

A multistate local CC2 response method for the calculation of analytic energy gradients with respect to nuclear displacements is presented for ground and electronically excited states. The gradient enables the search for equilibrium geometries of extended molecular systems. Laplace transform is used to partition the eigenvalue problem in order to obtain an effective singles eigenvalue problem and adaptive, state-specific local approximations. This leads to an approximation in the energy Lagrangian, which however is shown (by comparison with the corresponding gradient method without Laplace transform) to be of no concern for geometry optimizations. The accuracy of the local approximation is tested and the efficiency of the new code is demonstrated by application calculations devoted to a photocatalytic decarboxylation process of present interest.

Ledermüller, Katrin; Schütz, Martin, E-mail: martin.schuetz@chemie.uni-regensburg.de [Institute of Physical and Theoretical Chemistry, University of Regensburg, Universitätsstraße 31, D-93040 Regensburg (Germany)] [Institute of Physical and Theoretical Chemistry, University of Regensburg, Universitätsstraße 31, D-93040 Regensburg (Germany)

2014-04-28

144

Local CC2 response method based on the Laplace transform: analytic energy gradients for ground and excited states.  

PubMed

A multistate local CC2 response method for the calculation of analytic energy gradients with respect to nuclear displacements is presented for ground and electronically excited states. The gradient enables the search for equilibrium geometries of extended molecular systems. Laplace transform is used to partition the eigenvalue problem in order to obtain an effective singles eigenvalue problem and adaptive, state-specific local approximations. This leads to an approximation in the energy Lagrangian, which however is shown (by comparison with the corresponding gradient method without Laplace transform) to be of no concern for geometry optimizations. The accuracy of the local approximation is tested and the efficiency of the new code is demonstrated by application calculations devoted to a photocatalytic decarboxylation process of present interest. PMID:24784259

Ledermüller, Katrin; Schütz, Martin

2014-04-28

145

Excitation of Dark Plasmons in Metal Nanoparticles by a Localized Emitter  

Microsoft Academic Search

We study theoretically a dipole emitter placed near a metal nanoparticle and near small chains of two and three nanoparticles. The emitter can efficiently excite dark, or nonradiative, surface-plasmon modes in the nanostructures, in addition to the well-known bright modes. In the case of coupled nanoparticles, the origins of the bright and dark modes can be understood in the context

Mingzhao Liu; Tae-Woo Lee; Stephen K. Gray; Philippe Guyot-Sionnest; Matthew Pelton

2009-01-01

146

Fragility, Stokes-Einstein violation, and correlated local excitations in a coarse-grained model of an ionic liquid  

E-print Network

Dynamics of a coarse-grained model for the room-temperature ionic liquid, 1-ethyl-3-methylimidazolium hexafluorophosphate, couched in the united-atom site representation are studied via molecular dynamics simulations. The dynamically heterogeneous behavior of the model resembles that of fragile supercooled liquids. At or close to room temperature, the model ionic liquid exhibits slow dynamics, characterized by nonexponential structural relaxation and subdiffusive behavior. The structural relaxation time, closely related to the viscosity, shows a super-Arrhenius behavior. Local excitations, defined as displacement of an ion exceeding a threshold distance, are found to be mainly responsible for structural relaxation in the alternating structure of cations and anions. As the temperature is lowered, excitations become progressively more correlated. This results in the decoupling of exchange and persistence times, reflecting a violation of the Stokes-Einstein relation.

Daun Jeong; M. Y. Choi; Hyung. J. Kim; YounJoon Jung

2010-02-03

147

27 CFR 9.86 - Anderson Valley.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Anderson Valley. 9.86 Section 9.86 ...American Viticultural Areas § 9.86 Anderson Valley. (a) Name. The name of...area described in this section is “Anderson Valley.” (b) Approved...

2010-04-01

148

Ground-state properties of the periodic Anderson model  

NASA Technical Reports Server (NTRS)

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.

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

1987-01-01

149

Dendritic excitability and localization of GABA-mediated inhibition in spider mechanoreceptor neurons.  

PubMed

GABAergic inhibition of mechanosensory afferent axon terminals is a widespread phenomenon in vertebrates and invertebrates. Spider mechanoreceptor neurons receive efferent innervation on their peripherally located axons, somata and sensory dendrites, and the dendrites have recently been shown to be excitable. Excitability of the spider sensory neurons is inhibited by muscimol and GABA, agonists of ionotropic GABA receptors. Here we asked where in the neurons this inhibition occurs. We found no evidence for inhibition of action potentials in the sensory dendrites, but axonal action potentials were rapidly suppressed by both agonists. Earlier work showed that metabotropic GABA(B) receptors are located on the dendrites and distal somata of the spider sensory neurons, where they modulate voltage-activated conductances and may provide slower, prolonged inhibition. Therefore, GABA released from single peripheral efferents may activate both ionotropic and metabotropic receptor types, providing rapid suppression of axonal activity followed by slower inhibition that eventually prevents action potential initiation in the distal dendrites. PMID:15245479

Gingl, Ewald; French, Andrew S; Panek, Izabela; Meisner, Shannon; Torkkeli, Päivi H

2004-07-01

150

Current Focusing Sharpens Local Peaks of Excitation in Cochlear Implant Stimulation  

PubMed Central

Cochlear implant (CI) users’ spectral resolution is limited by the number of implanted electrodes, interactions between the electrodes, and the underlying neural population. Current steering has been proposed to increase the number of spectral channels beyond the number of physical electrodes, however, electric field interactions may limit CI users’ access to current-steered virtual channels (VCs). Current focusing (e.g. tripolar stimulation) has been proposed to reduce current spread and thereby reduce interactions. In this study, current steering and current focusing were combined in a four-electrode stimulation pattern, i.e. quadrupolar virtual channels (QPVCs). The spread of excitation was measured and compared between QPVC and Monopolar VC (MPVC) stimuli using a forward masking task. Results showed a sharper peak in the excitation pattern and reduced spread of masking for QPVC stimuli. Results from the forward masking study were compared with a previous study measuring VC discrimination ability and showed a weak relationship between spread of excitation and VC discriminability. The results suggest that CI signal processing strategies that utilize both current steering and current focusing might increase CI users’ functional spectral resolution by transmitting more channels and reducing channel interactions. PMID:20850513

Srinivasan, Arthi G.; Landsberger, David M.; Shannon, Robert V.

2010-01-01

151

M D Anderson Cancer Center  

Cancer.gov

This proposal will establish a Small Animal Imaging Research Program (SAIRP) at The University of Texas M. D. Anderson Cancer Center. The proposed SAIRP will complement the existing institutional facility that provides small animal imaging services to NIH funded investigators. The broad goal of this SAIRP is to develop novel imaging approaches to solve cancer related biological questions and evaluate new cancer therapies.

152

JOANNA E. ANDERSON CURRICULUM VITAE  

E-print Network

of conflict discussions. Talk presented at the annual meeting of the Canadian Positive Psychology Association with low self-esteem derogate a partner's sacrifices. Talk presented at the annual meeting of the American1 JOANNA E. ANDERSON CURRICULUM VITAE Postdoctoral Fellow Department of Psychology Cornell

153

UNIVERSALITIES: FROM ANDERSON LOCALIZATION TO QUANTUM CHAOS  

E-print Network

Magnetoconductance 34 4.4.6. Inelastic Processes 35 4.5. Quasi­Elastic Scattering 38 4.6. Noise and Dephasing 40 4.2.3. Magnetoconductivity 88 10.2.4. Dielectric Response of a Periodic Irregular Structures 89 10.3. Wavefunction

Simons, Ben

154

Dual effect of local anesthetics on the function of excitable rod outer segment disk membrane  

SciTech Connect

The effects of local anesthetics and a divalent cation, Ca2+, on the function of rhodopsin were estimated from the measurements of light-induced proton uptake. The light-induced proton uptake by rhodopsin in the rod outer segment disk membrane was enhanced at lower pH (4) but depressed at higher pHs (6 to 8) by the tertiary amine local anesthetics lidocaine, bupivacaine, tetracaine, and dibucaine. The order of local anesthetic-induced depression of the proton uptake followed that of their clinical anesthetic potencies. The depression of the proton uptake versus the concentration of the uncharged form of local anesthetic nearly describes the same curve for small and large dose of added anesthetic. Furthermore, a neutral local anesthetic, benzocaine, depressed the proton uptake at all pHs between 4 and 7. These results indicate that the depression of the proton uptake is due to the effect of only the uncharged form. It is hypothesized that the uncharged form of local anesthetics interacts hydrophobically with the rhodopsin in the disk membrane. The dual effect of local anesthetics on the proton uptake, on the other hand, suggests that the activation of the function of rhodopsin may be caused by the charged form. There was no significant change in the light-induced proton uptake by rhodopsin when 1 mM of Ca2+ was introduced into the disk membrane at varying pHs in the absence or presence of local anesthetics. This fact indicates that Ca2+ ion does not influence the diprotonating process of metarhodopsin; neither does it interfere with the local anesthetic-induced changes in the rhodopsin molecule.

Mashimo, T.; Abe, K.; Yoshiya, I.

1986-04-01

155

Solvent Effects on the Optical Spectra and Excited-State Decay of Triphenylamine-thiadiazole with Hybridized Local Excitation and Intramolecular Charge Transfer.  

PubMed

The triphenylamine-thiadiazole molecule (TPA-NZP) is a newly popular, highly efficient OLED fluorescent emitter with exciton utilization efficiency exceeding the upper limit of spin statistics (25%). In this work, the optical spectra and the radiative and nonradiative decay rate constants have been investigated theoretically for TPA-NZP in hexane, ethyl ether, tetrahydrofuran, and dimethylformamide solvents, in comparison with the gas phase. We observed the evolutions of the excited states from the hybridized local and charge-transfer (HLCT) character to complete intramolecular charge transfer (CT) character with the increase of the solvent polarities. It is found that upon increasing the solvent polarity, the amount of red shift in the absorption peak is much less than that of emission, resulting in breakdown of the mirror symmetry. This is because that 0-0 transition energy is red-shifted but the vibrational relaxation increases with the solvent polarity, leading to subtraction in absorption while addition in emission. The radiative decay rate constant is calculated to be almost independent of polarity. The nonradiative decay rate increases by almost one order of magnitude from that in nonpolar hexane to the strongly polarized dimethylformamide, which is attributed to the dual effects of the red shift in the gap and enhancement of the vibrational relaxation by solvent polarity. PMID:25402947

Fan, Di; Yi, Yuanping; Li, Zhendong; Liu, Wenjian; Peng, Qian; Shuai, Zhigang

2014-11-25

156

Dynamic Localization of Electronic Excitation in Photosynthetic Complexes Revealed with Chiral Two-Dimensional Spectroscopy  

PubMed Central

Time-resolved ultrafast optical probes of chiral dynamics provide a new window allowing us to explore how interactions with such structured environments drive electronic dynamics. Incorporating optical activity into time-resolved spectroscopies has proven challenging due to the small signal and large achiral background. Here, we demonstrate that two-dimensional electronic spectroscopy can be adapted to detect chiral signals and that these signals reveal how excitations delocalize and contract following excitation. We dynamically probe the evolution of chiral electronic structure in the light harvesting complex 2 of purple bacteria following photoexcitation by creating a chiral two-dimensional mapping. The dynamics of the chiral two-dimensional signal directly reports on changes in the degree of delocalization of the excitonic state following photoexcitation. The mechanism of energy transfer in this system may enhance transfer probability due to the coherent coupling among chromophores while suppressing fluorescence that arises from populating delocalized states. This generally applicable spectroscopy will provide an incisive tool to probe ultrafast transient molecular fluctuations that are obscured in non-chiral experiments. PMID:24504144

Fidler, Andrew F.; Singh, Ved P.; Long, Phillip D.; Dahlberg, Peter D.; Engel, Gregory S.

2014-01-01

157

Characterization of the Anderson metal-insulator transition for non ergodic operators and application  

E-print Network

We study the Anderson metal-insulator transition for non ergodic random Schr\\"odinger operators in both annealed and quenched regimes, based on a dynamical approach of localization, improving known results for ergodic operators into this more general setting. In the procedure, we reformulate the Bootstrap Multiscale Analysis of Germinet and Klein to fit the non ergodic setting. We obtain uniform Wegner Estimates needed to perform this adapted Multiscale Analysis in the case of Delone-Anderson type potentials, that is, Anderson potentials modeling aperiodic solids, where the impurities lie on a Delone set rather than a lattice, yielding a break of ergodicity. As an application we study the Landau operator with a Delone-Anderson potential and show the existence of a mobility edge between regions of dynamical localization and dynamical delocalization.

Constanza Rojas-Molina

2011-10-31

158

IR spectrum and localization of excitation of reaction center of photosystem II in triplet state  

NASA Astrophysics Data System (ADS)

Using the density functional theory, vibrations of different model forms of the chlorophyll a molecule in the ground and triplet states have been calculated. The assignment of the experimental difference IR spectrum corresponding to the formation of the triplet state of the photosynthetic reaction center of photosystem II has been proposed on this basis. It has been shown that molecules of accessory chlorophyll B A and B B located between the special pair and H A and H B pheophytin molecules can be involved in the intermolecular hydrogen bond with the water molecule. The energy of this interaction in the triplet state of molecules for B A is larger on 6 kcal/mol. This allows us to relate this pigment to the location of the triplet excitation at the reaction center of photosystem II.

Ivashin, N. V.

2010-04-01

159

America's First Illustrator: Alexander Anderson  

NSDL National Science Digital Library

America has produced many notable wood engravers, but Alexander Anderson is one of the first to have name recognition. Born in 1775, he spent his lifetime crafting illustrations for books, periodicals, newspapers, and other commercial ephemera. This delightful digital collection from the New York Public Library brings together sixteen scrapbooks containing almost 10,000 wood engravings by Anderson. Visitors can click on the "Browse Source Titles" area to view the various volumes, and the subjects covered here are quite diverse. Even a cursory search returns dozens of cat engravings, illustrations of slaves, and lottery advertisements. For anyone with an interest in 19th century material culture, this collection is truly wonderful. It is worth making several return trips to get a full sense of the offerings here, and it is one that will bring new rewards upon each visit.

160

Anderson testifies on Planet Earth  

NASA Astrophysics Data System (ADS)

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.”

Wainger, Lisa A.

161

MgB2 nonlinear properties investigated under localized high rf magnetic field excitation  

NASA Astrophysics Data System (ADS)

The high transition temperature and low surface resistance of MgB2 attracts interest in its potential application in superconducting radio frequency accelerating cavities. However, compared to traditional Nb cavities, the viability of MgB2 at high rf fields is still open to question. Our approach is to study the nonlinear electrodynamics of the material under localized rf magnetic fields. Because of the presence of the small superconducting gap in the ? band, the nonlinear response of MgB2 at low temperature is potentially complicated compared to a single-gap s-wave superconductor such as Nb. Understanding the mechanisms of nonlinearity coming from the two-band structure of MgB2, as well as extrinsic sources of nonlinearity, is an urgent requirement. A localized and strong rf magnetic field, created by a magnetic write head, is integrated into our nonlinear-Meissner-effect scanning microwave microscope [T. Tai , IEEE Trans. Appl. Supercond. 21, 2615 (2011)ITASE91051-822310.1109/TASC.2010.2096531]. MgB2 films with thickness 50 nm, fabricated by a hybrid physical-chemical vapor deposition technique on dielectric substrates, are measured at a fixed location and show a strongly temperature-dependent third harmonic response. We propose that several possible mechanisms are responsible for this nonlinear response.

Tai, Tamin; Ghamsari, B. G.; Tan, T.; Zhuang, C. G.; Xi, X. X.; Anlage, Steven M.

2012-12-01

162

[Anderson-Fabry disease and renal transplantation].  

PubMed

Anderson-Fabry disease is a rare disease associated with progressive accumulation of globotriaosylceramide in visceral organs and vascular endothelium. The disease primarily affects male patients. It has long been considered that females are asymptomatic carriers of Anderson-Fabry disease. However, recent results demonstrated a significant proportion of symptomatic affected females. We present our experience in the treatment of patients with Anderson-Fabry disease having received allograft from deceased donor, as well as follow-up of patients having received allograft from donor with unrecognized Anderson-Fabry disease. PMID:22359912

Basi?-Juki?, Nikolina; Kes, Petar; Hudolin, Tvrtko; Mesar, Ines; Cori?, Marijana; Kastelan, Zeljko

2011-01-01

163

Lithium abundances of halo dwarfs based on excitation temperature. I. Local thermodynamic equilibrium  

NASA Astrophysics Data System (ADS)

Context: The discovery of the Spite plateau in the abundances of 7Li for metal-poor stars led to the determination of an observationally deduced primordial lithium abundance. However, after the success of the Wilkinson Microwave Anisotropy Probe (WMAP) in determining the baryon density, ?_Bh2, there was a discrepancy between observationally determined and theoretically determined abundances in the case of 7Li. One of the most important uncertain factors in the calculation of the stellar 7Li abundance is the effective temperature, T_eff. Aims: We use sixteen metal-poor halo dwarfs to calculate new T_eff values using the excitation energy method. With this temperature scale we then calculate new Li abundances for this group of stars in an attempt to resolve the 7Li discrepancy. Methods: Using high signal-to-noise (S/N ? 100) spectra of 16 metal-poor halo dwarfs, obtained with the UCLES spectrograph on the AAT, measurements of equivalent widths from a set of unblended Fe I lines are made. These equivalent widths are then used to calculate new T_eff values with the use of the single line radiative transfer program WIDTH6, where we have constrained the gravity using either theoretical isochrones or the Hipparcos parallax, rather than the ionization balance. The lithium abundances of the stars are calculated with these temperatures. Results: The physical parameters are derived for the 16 programme stars, and two standards. These include T_eff, log g, [Fe/H], microturbulence and 7Li abundances. A comparison between the temperature scale of this work and those adopted by others has been undertaken. We find good consistency with the temperatures derived from the H? line by Asplund et al. (2006, ApJ, 644, 229), but not with the hotter scale of Meléndez & Ramírez (2004, ApJ, 615, L33). We also present results of the investigation into whether any trends between 7Li and metallicity or temperature are present in these metal-poor stars. Appendix A is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/493/601

Hosford, A.; Ryan, S. G.; García Pérez, A. E.; Norris, J. E.; Olive, K. A.

2009-01-01

164

Local chemical reaction of benzene on Cu(110) via STM-induced excitation  

NASA Astrophysics Data System (ADS)

We have investigated the mechanism of the chemical reaction of the benzene molecule adsorbed on Cu(110) surface induced by the injection of tunneling electrons using scanning tunneling microscopy (STM). With the dosing of tunneling electrons of the energy 2-5 eV from the STM tip to the molecule, we have detected the increase of the height of the benzene molecule by 40% in the STM image and the appearance of the vibration feature of the ?(C-H) mode in the inelastic tunneling spectroscopy (IETS) spectrum. It can be understood with a model in which the dissociation of C-H bonds occurs in a benzene molecule that induces a bonding geometry change from flat-lying to up-right configuration, which follows the story of the report of Lauhon and Ho on the STM-induced change of benzene on the Cu(100) surface. [L. J. Lauhon and W. Ho, J. Phys. Chem. A 104, 2463 (2000)]. The reaction probability shows a sharp rise at the sample bias voltage at 2.4 V, which saturates at 3.0 V, which is followed by another sharp rise at the voltage of 4.3 V. No increase of the reaction yield is observed for the negative sample voltage up to 5 eV. In the case of a fully deuterated benzene molecule, it shows the onset at the same energy of 2.4 eV, but the reaction probability is 103 smaller than the case of the normal benzene molecule. We propose a model in which the dehydrogenation of the benzene molecule is induced by the formation of the temporal negative ion due to the trapping of the electrons at the unoccupied resonant states formed by the ? orbitals. The existence of the resonant level close to the Fermi level (˜2.4 eV) and multiple levels in less than ˜5 eV from the Fermi level, indicates a fairly strong interaction of the Cu-?* state of the benzene molecule. We estimated that the large isotope effect of ˜103 can be accounted for with the Menzel-Gomer-Redhead (MGR) model with an assumption of a shallow potential curve for the excited state.

Komeda, T.; Kim, Y.; Fujita, Y.; Sainoo, Y.; Kawai, Maki

2004-03-01

165

Boson localization and excitations of liquid {sup 4}He confined in gelsil  

SciTech Connect

We present neutron scattering measurements of the phonon-roton (P-R) modes of liquid {sup 4}He at saturated vapor pressure confined in 44 A mean pore diameter gelsil in the wave vector range 0.4{<=}Q{<=}2.15 A{sup -1}. Layer modes, modes which propagate in the liquid layers adjacent to the porous media walls, were also observed at wave vectors in the roton region (Q{approx_equal}1.95 A{sup -1}) but not at Q < or approx. 1.7 A{sup -1}. The first goal is to document the filling dependence of the dynamic response and of the P-R mode energies and widths more systematically than has been done in the past. As the gelsil is filled with {sup 4}He, the P-R and layer modes are first observed at a fractional filling of f=76% at low temperature (T=0.4 K). At fillings f=76%, the P-R mode energies lie below the bulk superfluid {sup 4}He values in the wave vector range 0.4{<=}Q{<=}1.7 A{sup -1}, especially at Q{approx_equal}1.1 A{sup -1}, as observed in helium films. As filling is increased, the intensity in the P-R mode increases markedly and the P-R mode energies move toward bulk superfluid values taking bulk values at full filling. The second goal is to determine the temperature dependence of the intensity in the P-R modes in a media in which the superfluid-normal transition temperature T{sub c}=1.92 K is independently known and lies well below the bulk liquid value T{sub {lambda}}=2.17 K. As temperature is increased, the intensity in the P-R and layer modes decreases. However, a well-defined P-R mode is observed at temperatures up to T{approx_equal}2.15 K, above T{sub c}=1.92 K. Since well-defined modes exist because there is Bose-Einstein condensation (BEC), this suggests that there is BEC above T{sub c}, probably localized. Localized BEC appears to exist up to T{approx_equal}T{sub {lambda}}.

Albergamo, Francesco [European Synchrotron Radiation Facility, Boite Postale 220, F-38043 Grenoble Cedex (France); Bossy, Jacques [Centre de Recherche sur les Tres Basses Temperatures, CNRS, BP 166, 38042 Grenoble Cedex 9 (France); Pearce, Jonathan V. [Institut Laue-Langevin, BP 156, 38042 Grenoble (France); Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716-2570 (United States); Schober, Helmut [Institut Laue-Langevin, BP 156, 38042 Grenoble (France); Glyde, Henry R. [Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716-2570 (United States)

2007-08-01

166

Photoluminescence Under XUV Excitation Plus a Method of Dipole Summation for Local Fields Calculations.  

NASA Astrophysics Data System (ADS)

Organic and inorganic phosphors have often been used in detectors as a method of converting soft x-rays into visible light, which can then be detected by such devices as photodiodes and CCD's. However, the energy dependence of photoluminescent efficiency has been poorly known. This dissertation reports measurements of photoluminescence as a function of energy from 11 to 450 eV for the phosphors yttrium oxysulfide (Y_2O _2S:Eu), yttrium oxide (Y_2 O_3:Eu), lanthanum oxysulfide (La_2O_2S:Tm), gadolinium oxysulfide (Gd_2O _2S:Tb), and strontium chlorophosphate (Sr _5Cl(PO_4_)3 :Eu). With inelastic electron scattering spectroscopy, the optical properties of these phosphors have also been measured from 2 to 160 eV. Using the measured absorption and reflection coefficients and a model originally derived by H. B. DeVore for semiconductors, it is shown that the major cause of structure in the soft x-ray efficiency of phosphors in this energy range is surface recombination of charge carriers. The efficiency vs. photon energy and change of efficiency vs. total photon dose of an organic phosphor, para-terphenyl, have also been measured. It is found that the data cannot be modeled with the Birks -Black function for quenching of luminescence. A new variation of the Birks-Black function is developed. This function and an empirical function are used to model the damage data, and show that the damage rate goes as approximately the second power of the energy of the incident photons causing the damage. In the second part of this dissertation, a new method for computing momentum-dependent local fields is described. This method makes it possible to relatively quickly perform the dipole summations necessary for calculating the B(q) function for tetragonal lattices, including complex perovskites. Some results are demonstrated for aspect ratios of a simple lattice and for the perovskite structures of two high-temperature superconductors.

Benitez, Eva Lopdrup

167

Spin-dependent localized Hartree-Fock density-functional calculation of singly, doubly, and triply excited and Rydberg states of He- and Li-like ions  

E-print Network

A spin-dependent density-functional approach for the calculation of highly and multiply excited state of atomic system is proposed based on the localized Hartree-Fock density-functional method and Slater’s diagonal sum rule. In this approach...

Chu, Shih-I; Zhou, Zhongyuan

2005-02-28

168

Thermalization processes in interacting Anderson insulators  

NASA Astrophysics Data System (ADS)

This paper describes experiments utilizing a unique property of electron glasses to gain information on the fundamental nature of the interacting Anderson-localized phase. The methodology is based on measuring the energy absorbed by the electronic system from alternating electromagnetic fields as a function of their frequency. Experiments on three-dimensional (3D) amorphous indium-oxide films suggest that, in the strongly localized regime, the energy spectrum is discrete and inelastic electron-electron events are strongly suppressed. These results imply that, at low temperatures, electron thermalization and finite conductivity depend on coupling to the phonon bath. The situation is different for samples nearing the metal-insulator transition; in insulating samples that are close to the mobility edge, energy absorption persists to much higher frequencies. Comparing these results with previously studied 2D samples [Ovadyahu, Phys. Rev. Lett. 108, 156602 (2012), 10.1103/PhysRevLett.108.156602] demonstrates that the mean-level spacing (on a single-particle basis) is not the only relevant scale in this problem. The possibility of delocalization by many-body effects and the relevance of a nearby mobility edge (which may be a many-body edge) are discussed.

Ovadyahu, Z.

2015-01-01

169

Topological approximation of the nonlinear Anderson model  

NASA Astrophysics Data System (ADS)

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 ? t?, with the exponent ? =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 transport.

Milovanov, Alexander V.; Iomin, Alexander

2014-06-01

170

Local excitation and emission dynamics of an isolated single basal-plane stacking-fault in GaN studied by spatio-time-resolved cathodoluminescence  

NASA Astrophysics Data System (ADS)

Local excitation and emission dynamics of an isolated “Type-I1” basal-plane stacking-fault (BSF) in very low dislocation density GaN were studied using spatio-time-resolved cathodoluminescence. The low temperature lifetime of the BSF emission was quantified to be 640 ps. The carrier diffusion length was estimated by observing the temporal delay of the BSF peak relative to the free-exciton signal as a function of distance from the BSF. The results indicate that the near-band-edge emission leads to subsequent optical excitation of the BSF that increases the apparent diffusion length. Limiting the observation volume can improve the spatial resolution.

Furusawa, Kentaro; Ishikawa, Yoichi; Ikeda, Hirotaka; Fujito, Kenji; Chichibu, Shigefusa F.

2015-03-01

171

Reproducible conductance fluctuations in macroscopic Anderson insulators  

SciTech Connect

We study theoretically the reproducible magnetoconductance fluctuations in macroscopic Anderson insulators where complex random interferences yield localization at a scale {xi} larger than the elastic mean free path {ital l}. Based on the hypothesis of large ergodic quantum fluctuations of {xi} when a flux quantum is applied through an area {xi}{sup 2}, we show that the normalized magnetoconductance fluctuations {delta}{ital G}{sub tot}/{ital G}{sub tot} is ({xi}{sub {ital p}}{sup {ital D}}/{Omega}{sub {ital e}{ital f}{ital f}}){sup 1/2} for ergodic field changes {Delta}{ital B}{similar to}{phi}{sub 0}/{xi}{sup 2}, where {xi}{sub {ital p}} is a percolation correlation length which approaches macroscopic length scales at very low temperatures, and {Omega}{sub {ital e}{ital f}{ital f}} is an effective volume for th classical self-averaging of the fluctuations.

Feng, S. (Department of Physics, University of California, Los Angeles, CA (USA)); Pichard, J. (Service de Physique du Solide et de Resonance Magnetique, Commissariat a l'Energie Atomique Saclay, 91191 Gif-sur-Yvette CEDEX, France (FR))

1991-08-05

172

Localization of Classical Waves II: Electromagnetic Waves.  

E-print Network

Localization of Classical Waves II: Electromagnetic Waves. Alexander Figotin \\Lambda Department We consider electromagnetic waves in a medium described by a position dependent dielectric constant at all times. Localization of electromagnetic waves is a consequence of Anderson localization

173

Strong-coupling limit of depleted Kondo- and Anderson-lattice models  

NASA Astrophysics Data System (ADS)

Fourth-order strong-coupling degenerate perturbation theory is used to derive an effective low-energy Hamiltonian for the Kondo-lattice model with a depleted system of localized spins. In the strong-J limit, completely local Kondo singlets are formed at the spinful sites which bind a fraction of conduction electrons. The low-energy theory describes the scattering of the excess conduction electrons at the Kondo singlets as well as their effective interactions generated by virtual excitations of the singlets. Besides the Hubbard term, already discussed by Nozières, we find a ferromagnetic Heisenberg interaction, an antiferromagnetic isospin interaction, a correlated hopping and, in more than one dimensions, three- and four-site interactions. The interaction term can be cast into highly symmetric and formally simple spin-only form using the spin of the bonding orbital symmetrically centered around the Kondo singlet. This spin is non-local. We show that, depending on the geometry of the depleted lattice, spatial overlap of the non-local spins around different Kondo singlets may cause ferromagnetic order. This is sustained by a rigorous argument, applicable to the half-filled model, by a variational analysis of the stability of the fully polarized Fermi sea of excess conduction electrons as well as by exact diagonalization of the effective model. A similar fourth-order perturbative analysis is performed for the depleted Anderson lattice in the limit of strong hybridization. Even in a parameter regime where the Schrieffer-Wolff transformation does not apply, this yields the same effective theory albeit with a different coupling constant.

Titvinidze, Irakli; Schwabe, Andrej; Potthoff, Michael

2015-02-01

174

Strong-coupling limit of depleted Kondo- and Anderson-lattice models  

NASA Astrophysics Data System (ADS)

Fourth-order strong-coupling degenerate perturbation theory is used to derive an effective low-energy Hamiltonian for the Kondo-lattice model with a depleted system of localized spins. In the strong- J limit, completely local Kondo singlets are formed at the spinful sites which bind a fraction of conduction electrons. The low-energy theory describes the scattering of the excess conduction electrons at the Kondo singlets as well as their effective interactions generated by virtual excitations of the singlets. Besides the Hubbard term, already discussed by Nozières, we find a ferromagnetic Heisenberg interaction, an antiferromagnetic isospin interaction, a correlated hopping and, in more than one dimensions, three- and four-site interactions. The interaction term can be cast into highly symmetric and formally simple spin-only form using the spin of the bonding orbital symmetrically centered around the Kondo singlet. This spin is non-local. We show that, depending on the geometry of the depleted lattice, spatial overlap of the non-local spins around different Kondo singlets may cause ferromagnetic order. This is sustained by a rigorous argument, applicable to the half-filled model, by a variational analysis of the stability of the fully polarized Fermi sea of excess conduction electrons as well as by exact diagonalization of the effective model. A similar fourth-order perturbative analysis is performed for the depleted Anderson lattice in the limit of strong hybridization. Even in a parameter regime where the Schrieffer-Wolff transformation does not apply, this yields the same effective theory albeit with a different coupling constant.

Titvinidze, Irakli; Schwabe, Andrej; Potthoff, Michael

2015-02-01

175

Quantum Criticality of Quasi-One-Dimensional Topological Anderson Insulators  

NASA Astrophysics Data System (ADS)

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, ?) representing localization and topological properties, respectively. Surfaces of half-integer valued ? 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.

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

2014-05-01

176

Proposed radiofrequency phased-array excitation scheme for homogenous and localized 7-Tesla whole-body imaging based on full-wave numerical simulations.  

PubMed

In this article, a radiofrequency (RF) excitation scheme for 7-Tesla (T) whole-body applications is derived and analyzed using the finite difference time domain (FDTD) method. Important features of the proposed excitation scheme and coil (a potential 7T whole-body transverse electromagnetic [TEM] resonator design), from both operational and electromagnetic perspectives, are discussed. The choice of the coil's operational mode is unconventional; instead of the typical "homogenous mode," we use a mode that provides a null field in the center of the coil at low-field applications. Using a 3D FDTD implementation of Maxwell's equations, we demonstrate that the whole-body 7T TEM coil (tuned to the aforementioned unconventional mode and excited in an optimized near-field, phased-array fashion) can potentially provide 1) homogenous whole-slice (demonstrated in three axial, sagittal, and coronal slices) and 2) 3D localized (demonstrated in the heart) excitations. As RF power was not considered as a part of the optimization in several cases, the significant improvements achieved by whole-slice RF excitation came at the cost of considerable increases in RF power requirements. PMID:17260366

Abraham, Roney; Ibrahim, Tamer S

2007-02-01

177

Disorder-induced rapid localization of electron-hole plasmas in highly excited InxGa1-xN mixed crystals  

Microsoft Academic Search

In mixed semiconductor crystals, random potential fluctuations cause localized band-tail states below the band edge and control the optical spectrum and dynamics. We report the influence of these band-tail states on the dynamics of electron-hole plasmas in highly excited InxGa1-xN mixed crystals. Temporal changes in the luminescence spectrum of InxGa1-xN mixed crystals and their band-gap renormalization are completely different from

Daisuke Hirano; Takeshi Tayagaki; Yoshihiko Kanemitsu

2008-01-01

178

Astronaut Anderson Works in SPACEHAB  

NASA Technical Reports Server (NTRS)

The Space Shuttle Orbiter Columbia STS-107 mission launched January 16, 2003. STS-107 is strictly a multidiscipline microgravity and Earth science research mission involving 80-plus International experiments to be performed during 16-days, many of which will be managed by the Marshall Space Flight Center in Huntsville, Alabama. The majority of the research will be conducted in the Shuttle's mid deck, the area directly under the cockpit, and in the new SPACEHAB Research Double Module. This is the first flight for that module, which doubles the volume available for experiments and significantly increases the amount and complexity of research from the last dedicated Shuttle science mission, STS-95, flown in 1998 with a single SPACEHAB module. The pressurized module is carried in Columbia's payload bay and is accessible to the crew via a turnel from the Shuttle's mid deck. Pictured is an interesting view, looking through the adjoining tunnel, of astronaut Michael P. Anderson, mission specialist, performing work in SPACEHAB. The first shuttle mission in 2003, the STS-107 mission marks the 113th flight overall in NASA's Space Shuttle program, and the 28th flight of the Space Shuttle Orbiter Columbia.

2003-01-01

179

Tablet PC Enhanced Curricula Richard Anderson, Ruth Anderson, Oliver Chung, K. M. Davis,  

E-print Network

Tablet PC Enhanced Curricula Richard Anderson, Ruth Anderson, Oliver Chung, K. M. Davis, Peter write their answers on the slide on their tablets and send them back to the instructor Classroom Classroom Presenter · Tablet PC-based classroom interaction system · Supports inking on slides to integrate

Anderson, Richard

180

MD Anderson researchers find that chemotherapy is as effective before breast cancer surgery as after  

Cancer.gov

Whether chemotherapy is given before or after breast-conserving therapy does not have an impact on long-term local-regional outcomes, suggesting treatment success is due more to biologic factors than chemotherapy timing, according to a study by researchers at The University of Texas MD Anderson Cancer Center.

181

MD Anderson study finds side effects, complications, and mastectomy are more likely after partial breast irradiation:  

Cancer.gov

Accelerated partial breast irradiation (APBI) brachytherapy, the localized form of radiation therapy growing increasingly popular as a treatment choice for women with early-stage breast cancer, is associated with higher rate of later mastectomy, increased radiation-related toxicities and post-operative complications, compared to traditional whole breast irradiation (WBI), according to researchers from The University of Texas MD Anderson Cancer Center.

182

H{sub 2} EXCITATION STRUCTURE ON THE SIGHTLINES TO {delta} SCORPII AND {zeta} OPHIUCI: FIRST RESULTS FROM THE SUB-ORBITAL LOCAL INTERSTELLAR CLOUD EXPERIMENT  

SciTech Connect

We present the first science results from the Sub-orbital Local Interstellar Cloud Experiment (SLICE): moderate resolution 1020-1070 A spectroscopy of four sightlines through the local interstellar medium. High signal-to-noise (S/N) spectra of {eta} Uma, {alpha} Vir, {delta} Sco, and {zeta} Oph were obtained during a 2013 April 21 rocket flight. The SLICE observations constrain the density, molecular photoexcitation rates, and physical conditions present in the interstellar material toward {delta} Sco and {zeta} Oph. Our spectra indicate a factor of two lower total N(H{sub 2}) than previously reported for {delta} Sco, which we attribute to higher S/N and better scattered light control in the new SLICE observations. We find N(H{sub 2}) = 1.5 Multiplication-Sign 10{sup 19} cm{sup -2} on the {delta} Sco sightline, with kinetic and excitation temperatures of 67 and 529 K, respectively, and a cloud density of n{sub H} = 56 cm{sup -3}. Our observations of the bulk of the molecular sightline toward {zeta} Oph are consistent with previous measurements (N(H{sub 2}) Almost-Equal-To 3 Multiplication-Sign 10{sup 20} cm{sup -2} at T{sub 01}(H{sub 2}) = 66 K and T{sub exc} = 350 K). However, we detect significantly more rotationally excited H{sub 2} toward {zeta} Oph than previously observed. We infer a cloud density in the rotationally excited component of n{sub H} Almost-Equal-To 7600 cm{sup -3} and suggest that the increased column densities of excited H{sub 2} are a result of the ongoing interaction between {zeta} Oph and its environment; also manifest as the prominent mid-IR bowshock observed by WISE and the presence of vibrationally excited H{sub 2} molecules observed by the Hubble Space Telescope.

France, Kevin; Nell, Nicholas; Kane, Robert; Green, James C. [Center for Astrophysics and Space Astronomy, University of Colorado, 389 UCB, Boulder, CO 80309 (United States); Burgh, Eric B. [SOFIA/USRA, NASA Ames Research Center, M/S N232-12, Moffett Field, CA 94035 (United States); Beasley, Matthew, E-mail: kevin.france@colorado.edu [Planetary Resources, Inc., 93 S Jackson St 50680, Seattle, WA 98104-2818 (United States)

2013-07-20

183

Multifractality and electron-electron interaction at Anderson transitions  

NASA Astrophysics Data System (ADS)

Mesoscopic fluctuations and correlations of the local density of states are studied near metal-insulator transitions in disordered interacting electronic systems. We show that the multifractal behavior of the local density of states survives in the presence of Coulomb interaction. We calculate the spectrum of multifractal exponents in 2 +? spatial dimensions for symmetry classes characterized by broken (partially or fully) spin-rotation invariance and show that it differs from that in the absence of interaction. We also estimate the multifractal exponents at the Anderson metal-insulator transition in 2D systems with preserved spin-rotation invariance. Our results for multifractal correlations of the local density of states are in qualitative agreement with recent experimental findings.

Burmistrov, I. S.; Gornyi, I. V.; Mirlin, A. D.

2015-02-01

184

Time-dependent localized Hartree-Fock density-functional linear response approach for photoionization of atomic excited states  

E-print Network

We present a time-dependent localized Hartree-Fock density-functional linear response approach for the treatment of photoionization of atomic systems. This approach employs a spin-dependent localized Hartree-Fock exchange ...

Zhou, Zhongyuan; Chu, Shih-I

2009-05-13

185

Area laws in a many-body localized state and its implications for topological order  

E-print Network

The question whether Anderson insulators can persist to finite-strength interactions - a scenario dubbed many-body localization - has recently received a great deal of interest. The origin of such a many-body localized phase has been described as localization in Fock space, a picture we examine numerically. We then formulate a precise sense in which a single energy eigenstate of a Hamiltonian can be adiabatically connected to a state of a non-interacting Anderson insulator. We call such a state a many-body localized state and define a many-body localized phase as one in which almost all states are many-body localized states. We explore the possible consequences of this; the most striking is an area law for the entanglement entropy of almost all excited states in a many-body localized phase. We present the results of numerical calculations for a one-dimensional system of spinless fermions. Our results are consistent with an area law and, by implication, many-body localization for almost all states and almost all regions for weak enough interactions and strong disorder. However, there are rare regions and rare states with much larger entanglement entropies. Furthermore, we study the implications that many-body localization may have for topological phases and self-correcting quantum memories. We find that there are scenarios in which many-body localization can help to stabilize topological order at non-zero energy density, and we propose potentially useful criteria to confirm these scenarios.

Bela Bauer; Chetan Nayak

2013-06-30

186

2p excitation spectra of transition metal compounds as a probe of local electronic structure: A theoretical determination  

NASA Astrophysics Data System (ADS)

Excitation energies and oscillator strengths for Ni, Fe, Cr 2p and Pd 3p excitations in carbonyl, nitrosyl and bis-allyl complexes have been calculated at 1h-1p CI level, providing for an accurate choice of the basis set and an adequate treatment of relaxation. The spectra are found to be strongly sensitive to the nature of the ligands and the character of the metal?ligand bonding, and less dependent on the molecular symmetry and the d count of the metal atoms. An interpretation of the spectral pattern in terms of appropriate MO energy level diagrams is proposed that allows to correlate spectral data to the extent of the backbonding in ? ligand complexes.

Decleva, P.; Fronzoni, G.; Lisini, A.

1992-12-01

187

[Localization of the point of origin of the pre-excitation wave of type A Wolff-Parkinson White syndrome by echocardiography].  

PubMed

The echocardiographic findings in two patients with type A Wolff-Parkinson-White syndrome with pre-excitation localized at the anterior left ventricular wall are reported. The M-mode echocardiogram demonstrated premature anterior systolic motion of the postero-basal left ventricular endocardium that preceded the normal systolic contraction of the left ventricle. Despite the fact that the bundle of Kent reaches the epicardium of the left ventricular wall and that ventricular contraction probably begins at the subepicardial surface, the echocardiographic observations of the premature contractions were limited to the subendocardial layers. PMID:7469602

Sassé, L; Alvarez del Puerto, H

1980-01-01

188

Constrained dynamics of localized excitations causes a non-equilibrium phase transition in an atomistic model of glass formers.  

PubMed

Recent progress has demonstrated that trajectory space for both kinetically constrained lattice models and atomistic models can be partitioned into a liquid-like and an inactive basin with a non-equilibrium phase transition separating these behaviors. Recent work has also established that excitations in atomistic models have statistics and dynamics like those in a specific class of kinetically constrained models. But it has not been known whether the non-equilibrium phase transitions occurring in the two classes of models have similar origins. Here, we show that the origin is indeed similar. In particular, we show that the number of excitations identified in an atomistic model serves as the order parameter for the inactive-active phase transition for that model. In this way, we show that the mechanism by which excitations are correlated in an atomistic model - by dynamical facilitation - is the mechanism from which the active-inactive phase transition emerges. We study properties of the inactive phase and show that it is amorphous lacking long-range order. We also discuss the choice of dynamical order parameters. PMID:22583302

Speck, Thomas; Chandler, David

2012-05-14

189

Visual Absorption Capability1 Lee Anderson  

E-print Network

Visual Absorption Capability1 Lee Anderson 2a/ Jerry Mosier 2b/ Geoffrey Chandler 2c/ 1/ Submitted, Lassen National Forest, Susanville, California. Abstract: Visual absorption capability (VAC) is a tool development which is in harmony with the visual resource vis- ual absorption capability (VAC) is a tool which

Standiford, Richard B.

190

Some GroovyCool Research Chuck Anderson  

E-print Network

Some Groovy­Cool Research Chuck Anderson March 31, 1999 Abstract Very brief description of 2? If the hypothesis is not proved true, what are the conclusions? Identify possible pitfalls in your approach, i.eGraw­Hill, New York, NY, 1987. [3] J.L. McClelland, D.E. Rumelhart, and the PDP Research Group. Parallel

Anderson, Charles W.

191

A theory of magnetoconductance in Anderson insulators  

Microsoft Academic Search

We present a simple theory to understand the effect ofmagnetic field on the localisation length f in Anderson insulators. For thin wires, we find that f is doubled, a result recently derived through random matrix theories. For fi1nls or bulk samples, new results are obtained. In this case, the localisation length is multiplied by a non universal factor. We discuss

J. P. Bouchaud

1991-01-01

192

Biology Office Shauna C. Anderson, Director  

E-print Network

Biology Biology Office Shauna C. Anderson, Director 375 WIDB, (801) 422-4295 College of Biology program in biology has open enrollment. The Discipline A degree for students who desire a broad approach to biology, the major provides solid preparation for graduate schools in most fields of biology as well

Hart, Gus

193

FACULTY PRODUCERS Sarah Pia Anderson, Theatre & Dance  

E-print Network

Anderson, Theatre & Dance Liz Constable, Film Studies Jesse Drew, Technocultural Studies John Iacovelli Cholerton, Graphic Designer. 2008 SAVE THE DATE DEPARTMENT OF THEATRE & DANCE 9TH ANNUAL UC DAVIS FILM-sponsored by Film Studies and Art Studio DAVIS VARSITY THEATRE JUNE 3 - 4 , 2009 #12;ABOUT THE FILM FESTIVAL Welcome

Hernes, Peter J.

194

The Anderson Quin Cycle. Final report  

SciTech Connect

The objective of this study was to make a more refined evaluation of the Anderson Quin Cycle based on most recent information on the performance of various elements that will be used in the Anderson Quin Cycle. My original estimate of the work plan for evaluating and optimizing the Anderson Quin Cycle called for 7000 man hours of work. Since this grant was limited to 2150 man hours, we could not expect to achieve all the objectives within the allotted period of work. However, the most relevant program objectives have been completed as reported here. The analysis generally confirms the results originally estimated in my paper on the subject. (Ref. 2) Further optimizations should show even higher efficiencies. The Anderson Quin Cycle (US Patent applied for) basically consists of 5 elements in the power cycle: A refrigeration system to cool and clean the inlet air before it enters the compressor that supplies air for the gas turbine; a gas turbine consisting of a compressor, combustor, and turbine; a steam boiler and steam turbine system using the heat from the exhaust gas out of the gas turbine; a vapor turbine cycle, which utilizes the condensed heat from the exhaust of the steam turbine and the exhaust gas heat leaving the steam boiler to operate a vapor turbine cycle which utilizes another fluid than water, in this case isobutane; and the fifth element consists of a gas cooler and heat pump system, which removes the heat from the exhaust gas to lower its temperature essentially to atmospheric temperature, and at the same time permits treatment of the exhaust gas to remove acid components such as sulfur dioxide and nitrogen oxides. Current industry accepted component characteristics were incorporated in the performance analysis of the overall cycle, ensuring accurate and meaningful operating predictions. The characteristics and performance of each of the elements are described. The thermal efficiency of the optimized calculated Anderson Quin Cycle is 62 percent.

Anderson, J.H.; Bilbow, W.M.

1993-03-18

195

How to Use a Bed of Nails to Facilitate Excitement during a Science Road Show Presentation at Local Schools  

NASA Astrophysics Data System (ADS)

The authors will demonstrate how to use a bed of nails to pump up the students at local K-12 schools. The use during Science Road Show presentations will be addressed along with suggestions on how to build the drama and introduce humor and learning.

Pena, Fabian; Kridler, Shawn; Berger, Pete

2008-03-01

196

Universal Knight shift anomaly in the periodic Anderson model  

NASA Astrophysics Data System (ADS)

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.

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

2014-12-01

197

Conservation laws, radiative decay rates, and excited state localization in organometallic complexes with strong spin-orbit coupling  

E-print Network

There is longstanding fundamental interest in 6-fold coordinated $d^6$ ($t_{2g}^6$) transition metal complexes such as [Ru(bpy)$_3$]$^{2+}$ and Ir(ppy)$_3$, particularly their phosphorescence. This interest has increased with the growing realisation that many of these complexes have potential uses in applications including photovoltaics, imaging, sensing, and light-emitting diodes. In order to design new complexes with properties tailored for specific applications a detailed understanding of the low-energy excited states, particularly the lowest energy triplet state, $T_1$, is required. Here we describe a model of pseudo-octahedral complexes based on a pseudo-angular momentum representation and show that the predictions of this model are in excellent agreement with experiment - even when the deviations from octahedral symmetry are large. This model gives a natural explanation of zero-field splitting of $T_1$ and of the relative radiative rates of the three sublevels in terms of the conservation of time-revers...

Powell, B J

2015-01-01

198

Local magnetic properties of multiferroic Nd0.5Gd0.5Fe3(BO3)4 in the excited states of Nd3+ ion  

NASA Astrophysics Data System (ADS)

Polarized absorption spectra of single-crystal Nd0.5Gd0.5Fe3(BO3)4 were studied in the region of the transition 4I9/2?(4G5/2+2G7/2) in Nd3+ ion as a function of temperature (2-34 K) and magnetic field (0-65 kOe). The spectra of natural circular dichroism were measured in the range of 5-40 K. It was found out that the local magnetic properties in the vicinity of the excited ion substantially depended on its state. In particular, a weak ferromagnetic moment appears in some excited states. It was found out that the selection rules for electron transitions in the magnetically ordered state substantially deviated from those in the paramagnetic state of the crystal. They are different for different transitions and they are very sensitive to the orientation of the sublattice magnetic moment relative to the light polarization. In the spectrum of the natural circular dichroism, the transition is revealed which is not observed in the absorption spectrum.

Malakhovskii, A. V.; Gnatchenko, S. L.; Kachur, I. S.; Piryatinskaya, V. G.; Sukhachev, A. L.; Temerov, V. L.

2015-02-01

199

Mott-Anderson freeze-out and the strange matter "horn"  

E-print Network

We discuss the $\\sqrt{s}$-dependence of the $K^+/\\pi^+$ ratio in heavy-ion collisions (the "horn" effect) within a Mott-Anderson localization model for chemical freeze-out. The different response of pion and kaon radii to the hot and dense hadronic medium results in different freeze-out conditions. We demonstrate within a simple model that this circumstance enhances the "horn" effect relative to statistical models with universal chemical freeze-out.

Naskret, M; Dubinin, A

2015-01-01

200

MD Anderson-led study finds LIFR protein suppresses breast cancer metastasis  

Cancer.gov

A receptor protein suppresses local invasion and metastasis of breast cancer cells, the most lethal aspect of the disease, according to a research team headed by scientists from The University of Texas MD Anderson Cancer Center. Reporting in Nature Medicine, the team described using high-throughput RNA sequencing to identify the leukemia inhibitory factor receptor (LIFR) as a novel suppressor of breast cancer metastasis, the spread of the disease to other organs.

201

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

NASA Astrophysics Data System (ADS)

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.

Fernández, Julio F.; Alonso, Juan J.

2013-04-01

202

Forced magnetic reconnection in a plasma sheet with localized resistivity profile excited by lower hybrid drift type instability  

NASA Technical Reports Server (NTRS)

A forced magnetic reconnection process with a temporal evolution of resistivity is studied for a plasma sheet with a nonuniform resistivity profile based on the nonlocal mode structure of the lower hybrid drift type instability. The growth rate of the mode found is almost independent of the resistivity at the neutral sheet, but depends on the resistivity of the region of maximum density gradient away from the neutral sheet. This is studied by using both a nonlinear numerical MHD simulation and a linear theory. The mode may be relevant to the prevalent theoretical concept of MHD reconnection and the localized anomalous resistivity profile based on the lower hybrid drift instability.

Hoshino, M.

1991-01-01

203

Detection of Influenza Virus with Specific Subtype by Using Localized Surface Plasmons Excited on a Flat Metal Surface  

NASA Astrophysics Data System (ADS)

We report on a method to determine subtype of influenza viruses by using surface plasmons localized in microscopic region on a flat metal surface. In this method, refractive index variation arisen from interactions between viruses and their monoclonal antibodies is measured. The developed sensor shows stability of refractive index in the order of 10-4 against sample exchange. In our experiment, A/H1N1 viruses are distinguished from A/H3N2 viruses by using monoclonal antibodies immobilized on the metal surface. Since the measurement probe has the volume of ˜6 al, the method has potential to handle multiple subtypes in the measurement of a sample with ultra small volume.

Ning, Jun; Nagata, Kotaro; Ainai, Akira; Hasegawa, Hideki; Kano, Hiroshi

2013-08-01

204

Vigorous thermal excitations in a double-tetrahedral chain of localized Ising spins and mobile electrons mimic a temperature-driven first-order phase transition  

NASA Astrophysics Data System (ADS)

A hybrid spin-electron system defined on a one-dimensional double-tetrahedral chain, in which the localized Ising spin regularly alternates with two mobile electrons delocalized over a triangular plaquette, is exactly solved with the help of generalized decoration-iteration transformation. It is shown that a macroscopic degeneracy of ferromagnetic and ferrimagnetic ground states arising from chiral degrees of freedom of the mobile electrons cannot be lifted by a magnetic field in contrast to a macroscopic degeneracy of the frustrated ground state, which appears due to a kinetically driven frustration of the localized Ising spins. An anomalous behavior of all basic thermodynamic quantities can be observed on account of massive thermal excitations, which mimic a temperature-driven first-order phase transition from the nondegenerate frustrated state to the highly degenerate ferrimagnetic state at nonzero magnetic fields. A substantial difference in the respective degeneracies is responsible for an immense low-temperature peak of the specific heat and very abrupt (almost discontinuous) thermal variations of the entropy and sublattice magnetizations.

Gálisová, Lucia; Stre?ka, Jozef

2015-02-01

205

ADOLESCENT IDENTITIES AND SEXUAL BEHAVIOR: AN EXAMINATION OF ANDERSON’S ‘PLAYER’ HYPOTHESIS  

PubMed Central

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 African American respondents, those affiliated with liberal peers and young men who initially report a relatively high number of sexual partners are more likely to resonate with this identity label. Nevertheless, analyses reveal that a number of players within the sample are not disadvantaged African American youth, and there is considerable variability in their attitude and behavior profiles. Findings based on longitudinal analyses indicate that the player identity is a significant predictor of later variations in self-reported sexual behavior, net of traditional predictors, including prior behavior. Yet results of in-depth interviews conducted with a subset of the respondents complicate these quantitative findings, highlighting that young men’s perceptions of this identity are not as uniformly positive as Anderson’s depiction might lead us to expect. PMID:20161097

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

2009-01-01

206

The Economics of Censorship Resistance George Danezis and Ross Anderson  

E-print Network

The Economics of Censorship Resistance George Danezis and Ross Anderson University of Cambridge.Anderson)@cl.cam.ac.uk Abstract. We propose the first economic model of censorship resis- tance. Early peer-to-peer systems and resistance to censorship. Our results may have wider application too. 1 Introduction Peer-to-peer designs

Danezis, George

207

Cardiac magnetic resonance imaging illustrating Anderson–Fabry disease progression  

PubMed Central

Anderson–Fabry disease is an X-linked lysosomal storage disorder resulting from a deficiency of the enzyme ?-galactosidase A (?-Gal A) and subsequent cellular storage of the enzyme's substrate globotriaosylceramide (Gb3) and related glycosphingolipids. We report a case of Anderson–Fabry disease with cardiac involvement evaluated with cardiovascular MRI. Disease progression was observed despite enzyme replacement therapy. PMID:21088081

Imbriaco, M; Messalli, G; Avitabile, G; Cuocolo, A; Maurea, S; Soscia, F; Pisani, A

2010-01-01

208

Cardiac magnetic resonance imaging illustrating Anderson-Fabry disease progression.  

PubMed

Anderson-Fabry disease is an X-linked lysosomal storage disorder resulting from a deficiency of the enzyme ?-galactosidase A (?-Gal A) and subsequent cellular storage of the enzyme's substrate globotriaosylceramide (Gb3) and related glycosphingolipids. We report a case of Anderson-Fabry disease with cardiac involvement evaluated with cardiovascular MRI. Disease progression was observed despite enzyme replacement therapy. PMID:21088081

Imbriaco, M; Messalli, G; Avitabile, G; Cuocolo, A; Maurea, S; Soscia, F; Pisani, A

2010-12-01

209

A characterization of the Anderson metal-insulator transport transition  

E-print Network

A characterization of the Anderson metal-insulator transport transition Fran¸cois Germinet1, Abel on the occasion of his Sixtieth Birthday Abstract. We investigate the Anderson metal-insulator transition a characterization of the metal-insulator transport transition. Moreover, we show that if there is such a transition

210

The University of Texas MD Anderson Cancer Center  

Cancer.gov

The University of Texas MD Anderson Cancer Center (MD Anderson) was established by the Texas State Legislature in 1941and is a free-standing, degree-granting health institution within The University of Texas System. Mission areas include patient care, research, education, and prevention.

211

Passive control of buckling deformation via Anderson Localization Phenomenon  

NASA Technical Reports Server (NTRS)

Buckling problems of two types of multi-span elastic plates with transverse stiffeners are considered using a method based on the finite difference calculus. The discreteness of the stiffeners is accounted for. It is found that the torsional rigidity of the stiffener plays an important role in the buckling mode pattern. When the torsional rigidity is properly adjusted, the stiffener can act as an isolator of deformation for the structure at buckling so that the deflection is only limited to a small area.

Elishakoff, Isaac; Li, Y. W.; Starnes, J. H., Jr.

1998-01-01

212

Between a metal and an insulator: the critical state of the Anderson transition  

E-print Network

Using a three-frequency one-dimensional kicked rotor experimentally realized with a cold atomic gas, we study the transport properties at the critical point of the metal-insulator Anderson transition. We accurately measure the time-evolution of an initially localized wavepacket and show that it displays at the critical point a scaling invariance characteristic of this second-order phase transition. The shape of the momentum distribution at the critical point is found to be in excellent agreement with the analytical form deduced from self-consistent theory of localization.

Gabriel Lemarié; Hans Lignier; Dominique Delande; Pascal Szriftgiser; Jean Claude Garreau

2010-05-10

213

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

ERIC Educational Resources Information Center

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…

Albert, Marc K.

2008-01-01

214

Cryogenic exciter  

DOEpatents

The disclosed technology is a cryogenic static exciter. The cryogenic static exciter is connected to a synchronous electric machine that has a field winding. The synchronous electric machine is cooled via a refrigerator or cryogen like liquid nitrogen. The static exciter is in communication with the field winding and is operating at ambient temperature. The static exciter receives cooling from a refrigerator or cryogen source, which may also service the synchronous machine, to selected areas of the static exciter and the cooling selectively reduces the operating temperature of the selected areas of the static exciter.

Bray, James William (Niskayuna, NY); Garces, Luis Jose (Niskayuna, NY)

2012-03-13

215

Effects of cyclosis on chloroplast-cytoplasm interactions revealed with localized lighting in Characean cells at rest and after electrical excitation.  

PubMed

Cytoplasmic streaming in Characean internodes enables rapid intracellular transport and facilitates interactions between spatially remote cell regions. Cyclosis-mediated distant interactions might be particularly noticeable under nonuniform illumination, in the vicinity of light-shade borders where metabolites are transported between functionally distinct cell regions. In support of this notion, chlorophyll fluorescence parameters assessed on a microscopic area of Chara corallina internodal cells (area of inspection, AOI) responded to illumination of nearby regions in asymmetric manner depending on the vector of cytoplasmic streaming. When a beam of white light was applied through a 400-?m optic fiber upstream of AOI with regard to the direction of cytoplasmic streaming, non-photochemical quenching (NPQ) developed after a lag period in AOI exposed to moderate intensity light. Conversely, no NPQ was induced in the same cell area when the beam position was shifted to an equal distance downstream of AOI. Light-response curves for the efficiency of photosystem II electron transport in chloroplasts differed markedly depending on the illumination pattern (whole-cell versus small area illumination) but these differences were eliminated after the inhibition of cytoplasmic streaming with cytochalasin B. Localized illumination promoted chloroplast fluorescence responses to electrical plasmalemma excitation at high light intensities, which contrasts to the requirement of low to moderate irradiances for observation of the stimulus-response coupling under whole-cell illumination. The results indicate that different photosynthetic capacities of chloroplasts under general and localized illumination are related to lateral transport of nonevenly distributed cytoplasmic components between the cell parts with dominant photosynthetic and respiratory metabolism. PMID:21708122

Bulychev, Alexander A; Dodonova, Svetlana O

2011-09-01

216

Spin-polarized density-matrix functional theory of the single-impurity Anderson model  

NASA Astrophysics Data System (ADS)

Lattice density functional theory (LDFT) is used to investigate spin excitations in the single-impurity Anderson model. In this method, the single-particle density matrix ?ij? with respect to the lattice sites replaces the wave function as the basic variable of the many-body problem. A recently developed two-level approximation (TLA) to the interaction-energy functional W[?] is extended to systems having spin-polarized density distributions and bond orders. This allows us to investigate the effect of external magnetic fields and, in particular, the important singlet-triplet gap ?E, which determines the Kondo temperature. Applications to finite Anderson rings and square lattices show that the gap ?E as well as other ground-state and excited-state properties are very accurately reproduced. One concludes that the spin-polarized TLA is reliable in all interaction regimes, from weak to strong correlations, for different hybridization strengths and for all considered impurity valence states. In this way the efficiency of LDFT to account for challenging electron-correlation effects is demonstrated.

Töws, W.; Pastor, G. M.

2012-12-01

217

Localization of Brain-Derived Neurotrophic Factor to Distinct Terminals of Mossy Fiber Axons Implies Regulation of Both Excitation and Feedforward Inhibition of CA3 Pyramidal Cells  

PubMed Central

Hippocampal dentate granule cells directly excite and indirectly inhibit CA3 pyramidal cells via distinct presynaptic terminal specializations of their mossy fiber axons. This mossy fiber pathway contains the highest concentration of brain-derived neurotrophic factor (BDNF) in the CNS, yet whether BDNF is positioned to regulate the excitatory and/or inhibitory pathways is unknown. To localize BDNF, confocal microscopy of green fluorescent protein transgenic mice was combined with BDNF immunohistochemistry. Approximately half of presynaptic granule cell–CA3 pyramidal cell contacts were found to contain BDNF. Moreover, enhanced neuronal activity virtually doubled the percentage of BDNF-immunoreactive terminals contacting CA3 pyramidal cells. To our surprise, BDNF was also found in mossy fiber terminals contacting inhibitory neurons. These studies demonstrate that mossy fiber BDNF is poised to regulate both direct excitatory and indirect feedforward inhibitory inputs to CA3 pyramdal cells and reveal that seizure activity increases the pool of BDNF-expressing granule cell presynaptic terminals contacting CA3 pyramidal cells. PMID:15601941

Danzer, Steve C.

2005-01-01

218

Critical charge fluctuations in a pseudogap Anderson model  

NASA Astrophysics Data System (ADS)

The Anderson impurity model with a density of states ? (? ) ?|?| r containing a power-law pseudogap centered on the Fermi energy (? =0 ) features for 0 local-moment phases. The observation of mixed valency in quantum critical ? -YbAlB4 has prompted study of this model away from particle-hole symmetry. The critical spin response associated with all Kondo destruction QCPs has been shown to be accompanied, for r =0.6 and noninteger occupation of the impurity site, by a divergence of the local charge susceptibility on both sides of the QCP. In this work, we use the numerical renormalization-group method to characterize the Kondo-destruction charge response using five critical exponents, which are found to assume nontrivial values only for 0.55 ?r <1 . For 0 local charge susceptibility shows no divergence at the QCP, but rather exhibits nonanalytic corrections to a regular leading behavior. Both the charge critical exponents and the previously obtained spin critical exponents satisfy a set of scaling relations derived from an ansatz for the free energy near the QCP. These critical exponents can all be expressed in terms of just two underlying exponents: the correlation-length exponent ? (r ) and the gap exponent ? (r ) . The ansatz predicts a divergent local charge susceptibility for ? <2 , which coincides closely with the observed range 0.55 ?r <1 . Many of these results are argued to generalize to interacting QCPs that have been found in other quantum impurity models.

Chowdhury, Tathagata; Ingersent, Kevin

2015-01-01

219

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

SciTech Connect

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.

Mueller, A.; Halbach, P.

1983-03-01

220

Anderson metal-insulator transitions with classical magnetic impurities  

SciTech Connect

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].

Jung, Daniel [School of Engineering and Science, Jacobs University Bremen gGmbH, Campus Ring 1, 28759 Bremen, Germany and Division of Advanced Materials Science, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of); Kettemann, Stefan [School of Engineering and Science, Jacobs University Bremen gGmbH,Campus Ring 1, 28759 Bremen, Germany and Division of Advanced Materials Science, Pohang University of Science and Technology (POSTECH), San 31, Hyoja-dong, Nam-gu, Pohang 790-784 (Korea, Republic of)

2014-08-20

221

MD Anderson study finds cancer related pain often undertreated  

Cancer.gov

More than one third of patients with invasive cancer are undertreated for their pain, with minorities twice as likely to not receive analgesics, according to research from The University of Texas MD Anderson Cancer Center.

222

Ferromagnetic order in the one-dimensional Anderson lattice  

NASA Astrophysics Data System (ADS)

Using bosonization an effective Hamiltonian is derived for the one-dimensional Anderson lattice model in the Toulouse limit. The effective Hamiltonian exhibits ferromagnetic ground state in the intermediate coupling regime.

Gulacsi, M.

2015-01-01

223

STS-107 M.S Michael Anderson at SPACEHAB  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- At SPACEHAB, STS-107 Mission Specialist Michael Anderson (gloved, in center) gets hands-on experience with equipment. Identified as a research mission, STS-107 is scheduled for launch July 19, 2001

2000-01-01

224

MD Anderson study shows why some brain cancers resist treatment  

Cancer.gov

Scientists at The University of Texas MD Anderson Cancer Center may have discovered why some brain cancer patients develop resistance to standard treatments including radiation and the chemotherapy agent temozolomide.

225

Magnetic Moments of Chromium-Doped Gold Clusters: The Anderson Impurity Model in Finite Systems  

E-print Network

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 and density functional theory study of size-selected free chromium-doped gold clusters. The observed size-dependence of the local magnetic moment can essentially be understood in terms of the Anderson impurity model. Electronic shell closure in the host metal minimizes the interaction of localized impurity states with the confined free electron gas and preserves the full magnetic moment of $\\unit[5]{\\mu_B}$ in $\\mathrm{CrAu}_{2}^{+}$ and $\\mathrm{CrAu}_{6}^{+}$ clusters. 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 generally stabilizes the local magnetic moment of the impurity.

Hirsch, K; Langenberg, A; Niemeyer, M; Langbehn, B; Möller, T; Terasaki, A; Issendorff, B v; Lau, J T

2013-01-01

226

Localization of Cold Atoms in State-Dependent Optical Lattices via a Rabi Pulse  

SciTech Connect

We propose a novel realization of Anderson localization in nonequilibrium states of ultracold atoms in an optical lattice. A Rabi pulse transfers part of the population to a different internal state with infinite effective mass. These frozen atoms create a quantum superposition of different disorder potentials, localizing the mobile atoms. For weakly interacting mobile atoms, Anderson localization is obtained. The localization length increases with increasing disorder and decreasing interaction strength, contrary to the expectation for equilibrium localization.

Horstmann, Birger; Duerr, Stephan [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, 85748 Garching (Germany); Roscilde, Tommaso [Laboratoire de Physique, CNRS UMR 5672, Ecole Normale Superieure de Lyon, Universite de Lyon, 46 Allee d'Italie, Lyon, F-69364 (France)

2010-10-15

227

Interpretation of high-dimensional numerical results for the Anderson transition  

NASA Astrophysics Data System (ADS)

The existence of the upper critical dimension d c2 = 4 for the Anderson transition is a rigorous consequence of the Bogoliubov theorem on renormalizability of ?4 theory. For d ? 4 dimensions, one-parameter scaling does not hold and all existent numerical data should be reinterpreted. These data are exhausted by the results for d = 4, 5 from scaling in quasi-one-dimensional systems and the results for d = 4, 5, 6 from level statistics. All these data are compatible with the theoretical scaling dependences obtained from Vollhardt and Wolfle's self-consistent theory of localization. The widespread viewpoint that d c2 = ? is critically discussed.

Suslov, I. M.

2014-12-01

228

Localization of Bogoliubov quasiparticles in interacting Bose gases with correlated disorder  

SciTech Connect

We study the Anderson localization of Bogoliubov quasiparticles (elementary many-body excitations) in a weakly interacting Bose gas of chemical potential {mu} subjected to a disordered potential V. We introduce a general mapping (valid for weak inhomogeneous potentials in any dimension) of the Bogoliubov-de Gennes equations onto a single-particle Schroedinger-like equation with an effective potential. For disordered potentials, the Schroedinger-like equation accounts for the scattering and localization properties of the Bogoliubov quasiparticles. We derive analytically the localization lengths for correlated disordered potentials in the one-dimensional geometry. Our approach relies on a perturbative expansion in V/{mu}, which we develop up to third order, and we discuss the impact of the various perturbation orders. Our predictions are shown to be in very good agreement with direct numerical calculations. We identify different localization regimes: For low energy, the effective disordered potential exhibits a strong screening by the quasicondensate density background, and localization is suppressed. For high-energy excitations, the effective disordered potential reduces to the bare disordered potential, and the localization properties of quasiparticles are the same as for free particles. The maximum of localization is found at intermediate energy when the quasicondensate healing length is of the order of the disorder correlation length. Possible extensions of our work to higher dimensions are also discussed.

Lugan, P. [Laboratoire Charles Fabry de l'Institut d'Optique, CNRS and Univ. Paris-Sud, Campus Polytechnique, RD 128, F-91127 Palaiseau cedex (France); Physikalisches Institut, Albert-Ludwigs-Universitaet, Hermann-Herder Strasse 3, D-79104 Freiburg (Germany); Sanchez-Palencia, L. [Laboratoire Charles Fabry de l'Institut d'Optique, CNRS and Univ. Paris-Sud, Campus Polytechnique, RD 128, F-91127 Palaiseau cedex (France)

2011-07-15

229

Numerical calculation of the fidelity for the Kondo and the Friedel-Anderson impurities  

NASA Astrophysics Data System (ADS)

The fidelities of the Kondo and the Friedel-Anderson (FA) impurities are calculated numerically. The ground states of both systems are calculated with the FAIR (Friedel artificially inserted resonance) theory. The ground state in the interacting systems is compared with a nullstate in which the interaction is zero. The different multi-electron states are expressed in terms of Wilson states. The use of N Wilson states simulates the use of a large effective number N eff of states. A plot of ln( F) versus N ? ln( N eff ) reveals whether one has an Anderson orthogonality catastrophe at zero energy. The results are at first glance surprising. The ln( F) - ln( N eff ) plot for the Kondo impurity diverges for large N eff . On the other hand, the corresponding plot for the symmetric FA impurity saturates for large N eff when the level spacing at the Fermi level is of the order of the singlet-triplet excitation energy. The behavior of the fidelity allows one to determine the phase shift of the electron states in this regime.

Bergmann, G.; Thompson, R. S.

2011-11-01

230

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)

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.

Kang, Kai; Qin, Shao-Jing; Wang, Chui-Lin

2010-10-01

231

P cell excitability AP excitability  

E-print Network

AP (mV) P (mV) DP(15) (ipsi) DP(15) (contra) ba d P cell excitability Vm I (nA) AP excitability Vm) Measurement of input resistance of P and cell 212 and the amplitude of the P-to-cell 212 synaptic potential. We hyperpolarized cell 212 to prevent it from generating action potentials during P cell stimulations

Gaudry, Quentin

232

Administration Noma Bennett Anderson, PhD  

E-print Network

-C ____________________________________________ For More Information Contact: The University of Tennessee Health Science Center College of Allied Health@uthsc.edu Website: www.uthsc.edu/allied/ The College of Allied Health Sciences I t is an exciting time for the allied health professions as we study and practice in an ever-changing health care environment. There has

Cui, Yan

233

Strong localization of majorana end States in chains of magnetic adatoms.  

PubMed

A recent experiment [Nadj-Perge et al, Science 346, 602 (2014)] gives possible evidence for Majorana bound states in chains of magnetic adatoms placed on a superconductor. While many features of the observed end states are naturally interpreted in terms of Majorana states, their strong localization remained puzzling. We consider a linear chain of Anderson impurities on a superconductor as a minimal model and treat it largely analytically within mean-field theory. We explore the phase diagram, the subgap excitation spectrum, and the Majorana wave functions. Owing to a strong velocity renormalization, the latter are localized on a scale which is parametrically small compared to the coherence length of the host superconductor. PMID:25815952

Peng, Yang; Pientka, Falko; Glazman, Leonid I; von Oppen, Felix

2015-03-13

234

Strong Localization of Majorana End States in Chains of Magnetic Adatoms  

NASA Astrophysics Data System (ADS)

A recent experiment [Nadj-Perge et al, Science 346, 602 (2014)] gives possible evidence for Majorana bound states in chains of magnetic adatoms placed on a superconductor. While many features of the observed end states are naturally interpreted in terms of Majorana states, their strong localization remained puzzling. We consider a linear chain of Anderson impurities on a superconductor as a minimal model and treat it largely analytically within mean-field theory. We explore the phase diagram, the subgap excitation spectrum, and the Majorana wave functions. Owing to a strong velocity renormalization, the latter are localized on a scale which is parametrically small compared to the coherence length of the host superconductor.

Peng, Yang; Pientka, Falko; Glazman, Leonid I.; von Oppen, Felix

2015-03-01

235

Excite Assistant  

NSDL National Science Digital Library

Just when the concept of "push" technology seems like yesterday's news, Excite, Inc. produces a handy little program, the Excite Assistant, that pushes data to you without being pushy. The Excite Assistant provides you with instant access to various types of up-to-date information such as the weather for your area, the broadcast TV shows on at the moment, updated stock quotes, your horoscope, and more. The information is summarized within the Assistant's window, but when an item requires expansion, your browser is launched. By far the most useful aspect of this program is the mail notification feature. If you use Excite's Web-based mail service, the Excite Assistant, if active, will play a sound and it's icon will blink when new mail arrives. The Assistant will display the subject line and who the mail is from; clicking on the new mail loads it in your browser. Excite Assistant runs on Win95/98/NT and is free but does display small ads.

236

The Innocence Project, Marvin AndersonSite: DNA Interactive (www.dnai.org)  

NSDL National Science Digital Library

Interviewee: Marvin Anderson DNAi Location:Applications>Human identification>Innocence>DNA and the Innocence Project On February 28, 2003, Marvin Anderson spoke at a function celebrating the 50th anniversary of the discovery of the structure of DNA.

2008-03-26

237

Anderson-Mott transition driven by spin disorder: spin glass transition and magnetotransport in amorphous GdSi.  

PubMed

A zero temperature Anderson-Mott transition driven by spin disorder can be "tuned" by an applied magnetic field to achieve colossal magnetoconductance. Usually this is not possible since spin disorder by itself cannot localize a high density electron system. However, the presence of strong structural disorder can realize this situation, self-consistently generating a disordered magnetic ground state. We explore such a model, constructed to understand amorphous GdSi, and highlight the emergence of a spin glass phase, Anderson-Mott signatures in transport and tunneling spectra, and unusual magneto-optical conductivity. We solve a disordered strong coupling fermion-spin-lattice problem essentially exactly on finite systems and account for all the qualitative features observed in magnetism, transport, and the optical spectra in this system. PMID:12857286

Majumdar, Pinaki; Kumar, Sanjeev

2003-06-13

238

STS-89 M.S. Michael Anderson suits up  

NASA Technical Reports Server (NTRS)

STS-89 Mission Specialist Michael Anderson smiles as he completes the donning of his launch/entry suit in the Operations and Checkout (O&C) Building. A major in the U.S. Air Force, Anderson has a master of science degree in physics from Creighton University. He and six fellow crew members will soon depart the O&C and head for Launch Pad 39A, where the Space Shuttle Endeavour will lift off during a launch window that opens at 9:43 p.m. EST, Jan. 22. STS-89 is the eighth of nine planned missions to dock the Space Shuttle with Russia's Mir space station.

1998-01-01

239

75 FR 8346 - Proposed CERCLA Administrative Settlement; Anderson-Calhoun Mine and Mill Site, Leadpoint, WA  

Federal Register 2010, 2011, 2012, 2013, 2014

...Proposed CERCLA Administrative Settlement; Anderson-Calhoun Mine and Mill Site, Leadpoint...associated with a removal action at the Anderson-Calhoun Mine and Mill Site in Leadpoint...553-0242. Comments should reference the Anderson-Calhoun Mine and Mill Site in...

2010-02-24

240

Generation of the S boxes of Tiger Ross Anderson 1 and Eli Biham 2  

E-print Network

Generation of the S boxes of Tiger Ross Anderson 1 and Eli Biham 2 1 Cambridge University, England is the title of the paper describing Tiger: ''Tiger ­ A Fast New Hash Function, by Ross Anderson and Eli Biham New Hash Function, by Ross Anderson and Eli Biham'',5); */ /* This code is written for little

Biham, Eli

241

Nuclear liability and the Price--Anderson Act  

Microsoft Academic Search

The Price-Anderson Act is viewed as meeting public needs in a unique and responsible way, reflecting the far-sightedness of those involved in the early development of nuclear power who saw the importance of building safety into each step of the program. An extension of the Act is advised as a first step in recognizing that many potential and real disasters

2009-01-01

242

Federal Technology Transfer Data 1987-2009 Gary Anderson  

E-print Network

. Among other things, this Act explicitly incorporated technology transfer into the mission of all federalFederal Technology Transfer Data 1987-2009 Gary Anderson Economist National Institute of Standards and Technology Economic Analysis Office October 2011 #12;1. Background In 1980, the Stevenson-Wydler Technology

Perkins, Richard A.

243

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

ERIC Educational Resources Information Center

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…

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

2007-01-01

244

Elizabeth Garrett Anderson and the professionalism of medical publicity  

Microsoft Academic Search

A B S T R A C T • This article examines how early women doctors managed their professional and public images in the second half of the nineteenth century through a case study of the career of the first medical woman to qualify in Britain: Elizabeth Garrett Anderson (1836—1917). In fighting for their cause, Victorian women doctors had to

Claire Brock

2008-01-01

245

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

246

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

247

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

PubMed

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 ?-galactosidase A (?-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. PMID:25030479

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

2015-03-01

248

Supporting Information Anderson and Natland 10.1073/pnas.1410229111  

E-print Network

at the 650-km discontinuity; SUMA mantle mixing; perched eclogite layer; and tracking slabs--an exerciseSupporting Information Anderson and Natland 10.1073/pnas.1410229111 SI Text Tomography and Mantle than 40 y. The plume vs. plate debate is part of the broader issue of mantle dynamics and geochemistry

Low, Steven H.

249

Parabolic Anderson model with a finite number of moving catalysts  

E-print Network

Parabolic Anderson model with a finite number of moving catalysts F. Castell, O. G¨un and G- actant" u under the influence of a "catalyst" . In the present paper we focus on the case where of particles A and B. A-particles represent "catalysts", B-particles represent "reactants" and the dynamics

Maillard, Grégory

250

TILING RECTANGLES, CYLINDERS, AND MOBIUS PETER G. ANDERSON  

E-print Network

TILING RECTANGLES, CYLINDERS, AND MOBIUS STRIPS PETER G. ANDERSON Abstract. We present a method the repertoires show in Figure 1: (1) Vertical dominoes and squares. (2) L-trimonoes and squares. (3) Large and small squares. (4) Vertical and horizontal dominoes. In all cases here, the short dimensions are 1

Anderson, Peter G.

251

Poisson statistics of eigenvalues in the hierarchical Anderson model  

E-print Network

We study the eigenvalue statistics for the hieracharchial Anderson model of Molchanov. We prove Poisson fluctuations at arbitrary disorder, when the the model has spectral dimension d<1. The proof is based on Minami's technique and we give an elementary exposition of the probabilistic arguments.

Evgenij Kritchevski

2007-10-13

252

A characterization of the Anderson metal-insulator transport transition  

E-print Network

A characterization of the Anderson metal-insulator transport transition Fran#24;cois Germinet 1) provides a characterization of the metal-insulator transport transition. Moreover, we show metallic regime characterized by extended states. The energy Eme at which this metal-insulator transition

253

Contemporary Mathematics The Anderson metal-insulator transport transition  

E-print Network

Contemporary Mathematics The Anderson metal-insulator transport transition Fran#24;cois Germinet and Abel Klein Abstract. We discuss a new approach to the metal-insulator transition for random operators exponent #12;(E) provides a characterization of the metal-insulator transport transition

254

What Do Consumers Believe About Future Gasoline Soren T. Anderson  

E-print Network

What Do Consumers Believe About Future Gasoline Prices? Soren T. Anderson Michigan State University of consumers about their expectations of future gasoline prices. Overall, we find that consumer beliefs follow a random walk, which we deem a reasonable forecast of gasoline prices, but we find a deviation from

Silver, Whendee

255

INET 2000 Anderson, Camp The Telecom Road Less Traveled  

E-print Network

Grameen Bank #12;3 INET 2000 Anderson, Camp GrameenPhone · Competes in urban and rural areas · Rural Rural Telecommunications Authority · TMIB (since 1997), · International Communication Technologies · Village entrepreneurs · Advantages ­ Rural population settled in villages ­ Billing infrastructure from

Camp, L. Jean

256

THE HULL OF RUDIN'S KLEIN BOTTLE JOHN T. ANDERSON  

E-print Network

THE HULL OF RUDIN'S KLEIN BOTTLE JOHN T. ANDERSON Abstract. In 1981 Walter Rudin exhibited a totally real embedding of the Klein bottle into C2. We show that the polynomially convex hull of Rudin's Klein bottle contains an open subset of C2. We also describe another totally real Klein bottle in C2

Anderson, John T.

257

The M. D. Anderson proton therapy system  

SciTech Connect

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 extracted from the synchrotron (energy can be changed pulse to pulse). The PTC-H is fully integrated with DICOM-RT ION interfaces for imaging, treatment planning, data management, and treatment control functions. Results: The proton therapy system passed all acceptance tests for both passive scattering and pencil beam scanning. Treatments with passive scattering began in May 2006 and treatments with the scanning system began in May 2008. The PTC-H was the first commercial system to demonstrate capabilities for IMPT treatments and the first in the United States to treat using SFUD techniques. The facility has been in clinical operation since May 2006 with up-time of approximately 98%. Conclusions: As with most projects for which a considerable amount of new technology is developed and which have duration spanning several years, at project completion it was determined that several upgrades would improve the overall system performance. Some possible upgrades are discussed. Overall, the system has been very robust, accurate, reproducible, and reliable. The authors found the pencil beam scanning system to be particularly satisfactory; prostate treatments can be delivered on the scanning nozzle in less time than is required on the passive scattering nozzle.

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 [Department of Radiation Oncology and Department of Radiation Physics, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston Texas 77030 (United States); Energy and Environmental Systems Laboratory, Hitachi, Ltd., 2-1, Omika-cho, Hitachi-shi, Ibaraki-ken 319-1221 (Japan); Hitachi Works, Hitachi, Ltd. Power Systems, 1-1, Saiwai-cho, 3-chome, Hitachi-shi, Ibaraki-ken 317-8511 (Japan)

2009-09-15

258

On Diversity of Configurations Generated by Excitable Cellular Automata with Dynamical Excitation Intervals  

NASA Astrophysics Data System (ADS)

Excitable cellular automata with dynamical excitation interval exhibit a wide range of space-time dynamics based on an interplay between propagating excitation patterns which modify excitability of the automaton cells. Such interactions leads to formation of standing domains of excitation, stationary waves and localized excitations. We analyzed morphological and generative diversities of the functions studied and characterized the functions with highest values of the diversities. Amongst other intriguing discoveries we found that upper boundary of excitation interval more significantly affects morphological diversity of configurations generated than lower boundary of the interval does and there is no match between functions which produce configurations of excitation with highest morphological diversity and configurations of interval boundaries with highest morphological diversity. Potential directions of future studies of excitable media with dynamically changing excitability may focus on relations of the automaton model with living excitable media, e.g. neural tissue and muscles, novel materials with memristive properties and networks of conductive polymers.

Adamatzky, Andrew

2012-11-01

259

Excited Delirium  

PubMed Central

Excited (or agitated) delirium is characterized by agitation, aggression, acute distress and sudden death, often in the pre-hospital care setting. It is typically associated with the use of drugs that alter dopamine processing, hyperthermia, and, most notably, sometimes with death of the affected person in the custody of law enforcement. Subjects typically die from cardiopulmonary arrest, although the cause is debated. Unfortunately an adequate treatment plan has yet to be established, in part due to the fact that most patients die before hospital arrival. While there is still much to be discovered about the pathophysiology and treatment, it is hoped that this extensive review will provide both police and medical personnel with the information necessary to recognize and respond appropriately to excited delirium. PMID:21691475

Takeuchi, Asia; Ahern, Terence L.; Henderson, Sean O.

2011-01-01

260

The chiral transition as an Anderson transition  

E-print Network

At low temperature the low-lying QCD Dirac spectrum obeys random matrix statistics. Recently we found that above $T_{c}$ the lowest part of the spectrum consists of localized modes that obey Poisson statistics. An interesting implication of this is that as the system crosses $T_{c}$ from above, the spectral statistics at $\\lambda=0$ changes from Poisson to random matrix. Here we study this transition and its possible implications for the finite temperature transition of QCD-like theories.

Matteo Giordano; Sandor D. Katz; Tamas G. Kovacs; Ferenc Pittler

2014-10-31

261

Magnetic Moments of Chromium-Doped Gold Clusters: The Anderson Impurity Model in Finite Systems  

NASA Astrophysics Data System (ADS)

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 ?B fully in CrAu2+ and almost fully in CrAu6+. 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.

Hirsch, K.; Zamudio-Bayer, V.; Langenberg, A.; Niemeyer, M.; Langbehn, B.; Möller, T.; Terasaki, A.; Issendorff, B. v.; Lau, J. T.

2015-02-01

262

Magnetic moments of chromium-doped gold clusters: the anderson impurity model in finite systems.  

PubMed

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??_{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. PMID:25768776

Hirsch, K; Zamudio-Bayer, V; Langenberg, A; Niemeyer, M; Langbehn, B; Möller, T; Terasaki, A; Issendorff, B V; Lau, J T

2015-02-27

263

Quantum Walks on Trees with Disorder: Decay, Diffusion, and Localization  

E-print Network

Quantum walks have been shown to have impressive transport properties compared to classical random walks. However, imperfections in the quantum walk algorithm can destroy any quantum mechanical speed-up due to Anderson localization. We numerically study the effect of static disorder on a quantum walk on the glued trees graph. For small disorder, we find that the dominant effect is a type of quantum decay, and not quantum localization. For intermediate disorder, there is a crossover to diffusive transport, while a localization transition is observed at large disorder, in agreement with Anderson localization on the Cayley tree.

Steven R. Jackson; Teng Jian Khoo; Frederick W. Strauch

2012-06-14

264

Decoherence-induced conductivity in the one-dimensional Anderson model  

SciTech Connect

We study the effect of decoherence on the electron transport in the one-dimensional Anderson model by means of a statistical model [1, 2, 3, 4, 5]. In this model decoherence bonds are randomly distributed within the system, at which the electron phase is randomized completely. Afterwards, the transport quantity of interest (e.g. resistance or conductance) is ensemble averaged over the decoherence configurations. Averaging the resistance of the sample, the calculation can be performed analytically. In the thermodynamic limit, we find a decoherence-driven transition from the quantum-coherent localized regime to the Ohmic regime at a critical decoherence density, which is determined by the second-order generalized Lyapunov exponent (GLE) [4].

Stegmann, Thomas; Wolf, Dietrich E. [Department of Physics, University of Duisburg-Essen and CENIDE, 47048 Duisburg (Germany); Ujsághy, Orsolya [Department of Theoretical Physics, Budapest University of Technology and Economics, Budafoki út 8., H-1521 Budapest (Hungary)

2014-08-20

265

Topologically invariant tensor renormalization group method for the Edwards-Anderson spin glasses model  

NASA Astrophysics Data System (ADS)

Tensor renormalization group (TRG) method is a real space renormalization group approach. It has been successfully applied to both classical and quantum systems. In this paper, we study a disordered and frustrated system, the two-dimensional Edwards-Anderson model, by a new topological invariant TRG scheme. We propose an approach to calculate the local magnetizations and nearest pair correlations simultaneously. The Nishimori multicritical point predicted by the topological invariant TRG agrees well with the recent Monte Carlo results. The TRG schemes outperform the mean-field methods on the calculation of the partition function. We notice that it might obtain a negative partition function at sufficiently low temperatures. However, the negative contribution can be neglected if the system is large enough. This topological invariant TRG can also be used to study three-dimensional spin glass systems.

Wang, Chuang; Qin, Shao-Meng; Zhou, Hai-Jun

2014-11-01

266

Classroom Presentation from the Tablet PC Richard J. Anderson* Ruth Anderson* Tammy VanDeGrift* Steven A. Wolfman* Ken Yasuhara*  

E-print Network

Classroom Presentation from the Tablet PC Richard J. Anderson* Ruth Anderson* Tammy Van the instructor uses a Tablet PC as a presentation device. The system was deployed in six university courses projector. The instructor displays slides from the tablet and can write on top of them. Various navigation

VanDeGrift, Tammy

267

STS-107 Crew Interviews: Michael Anderson, Mission Specialist  

NASA Technical Reports Server (NTRS)

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.

2002-01-01

268

Multi-Stepped Optogenetics: A Novel Strategy to Analyze Neural Network Formation and Animal Behaviors by Photo-Regulation of Local Gene Expression, Fluorescent Color and Neural Excitation  

NASA Astrophysics Data System (ADS)

The brain is one of the most complicated structures in nature. Zebrafish is a useful model to study development of vertebrate brain, because it is transparent at early embryonic stage and it develops rapidly outside of the body. We made a series of transgenic zebrafish expressing green-fluorescent protein related molecules, for example, Kaede and KikGR, whose green fluorescence can be irreversibly converted to red upon irradiation with ultra-violet (UV) or violet light, and Dronpa, whose green fluorescence is eliminated with strong blue light but can be reactivated upon irradiation with UV or violet-light. We have recently shown that infrared laser evoked gene operator (IR-LEGO) which causes a focused heat shock could locally induce these fluorescent proteins and the other genes. Neural cell migration and axonal pattern formation in living brain could be visualized by this technique. We also can express channel rhodopsine 2 (ChR2), a photoactivatable cation channel, or Natronomonas pharaonis halorhodopsin (NpHR), a photoactivatable chloride ion pump, locally in the nervous system by IR. Then, behaviors of these animals can be controlled by activating or silencing the local neurons by light. This novel strategy is useful in discovering neurons and circuits responsible for a wide variety of animal behaviors. We proposed to call this method ‘multi-stepped optogenetics’.

Hatta, Kohei; Nakajima, Yohei; Isoda, Erika; Itoh, Mariko; Yamamoto, Tamami

269

Accuracy of density functionals for molecular electronics: The Anderson junction  

NASA Astrophysics Data System (ADS)

The exact ground-state exchange-correlation functional of Kohn-Sham density functional theory yields the exact transmission through an Anderson junction at zero bias and temperature. The exact impurity charge susceptibility is used to construct the exact exchange-correlation potential. We analyze the successes and limitations of various types of approximations, including smooth and discontinuous functionals of the occupation, as well as symmetry-broken approaches.

Liu, Zhen-Fei; Bergfield, Justin P.; Burke, Kieron; Stafford, Charles A.

2012-04-01

270

A density functional that works for transport through Anderson junction  

NASA Astrophysics Data System (ADS)

Transport through an Anderson junction can be exactly described by density functional theory, at zero temperature and in the linear response regime. Using Bethe ansatz, we calculate the exact Kohn-Sham potential delivering the exact transmission. We propose a simple parametrization for the Kohn-Sham potential, using a known exact condition. Our parametrization faithfully reproduces numerical results, including the gradual development of the derivative discontinuity that is essential in describing Coulomb blockade correctly.

Liu, Zhenfei; Bergfield, Justin; Burke, Kieron; Stafford, Charles

2012-02-01

271

UT MD Anderson scientists discover secret life of chromatin:  

Cancer.gov

Chromatin--the intertwined histone proteins and DNA that make up chromosomes--constantly receives messages that pour in from a cell’s intricate signaling networks... But chromatin also talks back, scientists at The University of Texas M.D. Anderson Cancer Center report today in the journal Cell, issuing orders affecting a protein that has nothing to do with chromatin’s central role in gene transcription--the first step in protein formation.

272

STS-107 Payload Commander Michael Anderson suits up for TCDT  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- STS-107 Payload Commander Michael Anderson completes 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. .

2002-01-01

273

Anderson and Belnap’s Invitation to Sin  

Microsoft Academic Search

Quine has argued that modal logic began with the sin of confusing use and mention. Anderson and Belnap, on the other hand,\\u000a have offered us a way out through a strategy of nominalization. This paper reviews the history of Lewis’s early work in modal\\u000a logic, and then proves some results about the system in which “A is necessary” is intepreted

Alasdair Urquhart

2010-01-01

274

Solar hot water system installed at Anderson, South Carolina  

NASA Technical Reports Server (NTRS)

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.

1978-01-01

275

Block Lanczos density-matrix renormalization group method for general Anderson impurity models: Application to magnetic impurity problems in graphene  

NASA Astrophysics Data System (ADS)

We introduce a block Lanczos (BL) recursive technique to construct quasi-one-dimensional models, suitable for density-matrix renormalization group (DMRG) calculations, from single- as well as multiple-impurity Anderson models in any spatial dimensions. This new scheme, named BL-DMRG method, allows us to calculate not only local but also spatially dependent static and dynamical quantities of the ground state for general Anderson impurity models without losing elaborate geometrical information of the lattice. We show that the BL-DMRG method can be easily extended to treat a multiorbital Anderson impurity model where not only inter- and intraorbital Coulomb interactions but also Hund's coupling and pair hopping interactions are included. We also show that the symmetry adapted BL bases can be utilized, when it is appropriate, to reduce the computational cost. As a demonstration, we apply the BL-DMRG method to three different models for graphene with a structural defect and with a single hydrogen or fluorine absorbed, where a single Anderson impurity is coupled to conduction electrons in the honeycomb lattice. These models include (i) a single adatom on the honeycomb lattice, (ii) a substitutional impurity in the honeycomb lattice, and (iii) an effective model for a single carbon vacancy in graphene. Our analysis of the local dynamical magnetic susceptibility and the local density of states at the impurity site reveals that, for the particle-hole symmetric case at half-filling of electron density, the ground state of model (i) behaves as an isolated magnetic impurity with no Kondo screening, while the ground state of the other two models forms a spin-singlet state where the impurity moment is screened by the conduction electrons. We also calculate the real-space dependence of the spin-spin correlation functions between the impurity site and the conduction sites for these three models. Our results clearly show that, reflecting the presence or absence of unscreened magnetic moment at the impurity site, the spin-spin correlation functions decay as ? r-3, differently from the noninteracting limit (? r-2), for model (i) and as ? r-4, exactly the same as the noninteracting limit, for models (ii) and (iii) in the asymptotic r , where r is the distance between the impurity site and the conduction site. Finally, based on our results, we shed light on recent experiments on graphene where the formation of local magnetic moments as well as the Kondo-like behavior have been observed.

Shirakawa, Tomonori; Yunoki, Seiji

2014-11-01

276

High-field magnetoconductance in Anderson insulators  

SciTech Connect

We report on high-field magnetoconductance measurements made on indium-oxide films as a function of temperature and static disorder. Special emphasis is given to the strong-localization regime where the magnetoconductance reveals a negative contribution associated with a spin-alignment mechanism in addition to the positive contribution associated with orbital, quantum-coherence effects. While the overall features of the theoretically expected effects are observed in our experiments, they depart in certain ways from the detailed predictions. We discuss the merits and shortcomings of current models to describe them, in particular, as they apply to the regime where the localized wave functions become larger than the Bohr radius. The main results of this paper are both quantum interference and spin effects contribute to the magnetoconductance throughout the entire range studied. In the limit of very strong disorder, the quantum interference effects are faithfully described by the Nguyen {ital et} {ital al}. model. The spin effects, on the other hand, show only qualitative agreement with current models which are unable to account for the saturation field being insensitive to changes in disorder. {copyright} {ital 1996 The American Physical Society.}

Vaknin, A.; Frydman, A.; Ovadyahu, Z. [The Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel)] [The Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel); Pollak, M. [The University of California at Riverside, Riverside, California 92521 (United States)] [The University of California at Riverside, Riverside, California 92521 (United States)

1996-11-01

277

Effect of wave localization on plasma instabilities. Ph.D. Thesis  

NASA Technical Reports Server (NTRS)

The Anderson model of wave localization in random media is involved to study the effect of solar wind density turbulence on plasma processes associated with the solar type III radio burst. ISEE-3 satellite data indicate that a possible model for the type III process is the parametric decay of Langmuir waves excited by solar flare electron streams into daughter electromagnetic and ion acoustic waves. The threshold for this instability, however, is much higher than observed Langmuir wave levels because of rapid wave convection of the transverse electromagnetic daughter wave in the case where the solar wind is assumed homogeneous. Langmuir and transverse waves near critical density satisfy the Ioffe-Reigel criteria for wave localization in the solar wind with observed density fluctuations -1 percent. Numerical simulations of wave propagation in random media confirm the localization length predictions of Escande and Souillard for stationary density fluctations. For mobile density fluctuations localized wave packets spread at the propagation velocity of the density fluctuations rather than the group velocity of the waves. Computer simulations using a linearized hybrid code show that an electron beam will excite localized Langmuir waves in a plasma with density turbulence. An action principle approach is used to develop a theory of non-linear wave processes when waves are localized. A theory of resonant particles diffusion by localized waves is developed to explain the saturation of the beam-plasma instability. It is argued that localization of electromagnetic waves will allow the instability threshold to be exceeded for the parametric decay discussed above.

Levedahl, William Kirk

1987-01-01

278

Astronaut Clay Anderson Speaks With S.C. Students - Duration: 25:29.  

NASA Video Gallery

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,...

279

Detection of Local Wall Stiffness Drop in Steel-Lined Pressure Tunnels and Shafts of Hydroelectric Power Plants Using Steep Pressure Wave Excitation and Wavelet Decomposition  

E-print Network

Abstract: A new monitoring approach for detecting, locating, and quantifying structurally weak reaches of steel-lined pressure tunnels and shafts is presented. These reaches arise from local deterioration of the backfill concrete and the rock mass surrounding the liner. The change of wave speed generated by the weakening of the radial-liner supports creates reflection boundaries for the incident pressure waves. The monitoring approach is based on the generation of transient pressure with a steep wave front and the analysis of the reflected pressure signals using the fast Fourier transform and wavelet decomposition methods. Laboratory experiments have been carried out to validate the monitoring technique. The multilayer system (steel-concrete-rock) of the pressurized shafts and tunnels is modeled by a one-layer system of the test pipe. This latter was divided into several reaches having different wall stiffnesses. Different longitudinal placements of a steel, aluminum, and PVC pipe reach were tested to validate the identification method of the weak section. DOI: 10.1061/(ASCE)HY.1943-7900.0000478.

280

Local knockdown of the NaV1.6 sodium channel reduces pain behaviors, sensory neuron excitability, and sympathetic sprouting in rat models of neuropathic pain.  

PubMed

In the spinal nerve ligation (SNL) model of neuropathic pain, as in other pain models, abnormal spontaneous activity of myelinated sensory neurons occurs early and is essential for establishing pain behaviors and other pathologies. Sympathetic sprouting into the dorsal root ganglion (DRG) is observed after SNL, and sympathectomy reduces pain behavior. Sprouting and spontaneous activity may be mutually reinforcing: blocking neuronal activity reduces sympathetic sprouting, and sympathetic spouts functionally increase spontaneous activity in vitro. However, most studies in this field have used nonspecific methods to block spontaneous activity, methods that also block evoked and normal activity. In this study, we injected small inhibitory (si) RNA directed against the NaV1.6 sodium channel isoform into the DRG before SNL. This isoform can mediate high-frequency repetitive firing, like that seen in spontaneously active neurons. Local knockdown of NaV1.6 markedly reduced mechanical pain behaviors induced by SNL, reduced sympathetic sprouting into the ligated sensory ganglion, and blocked abnormal spontaneous activity and other measures of hyperexcitability in myelinated neurons in the ligated sensory ganglion. Immunohistochemical experiments showed that sympathetic sprouting preferentially targeted NaV1.6-positive neurons. Under these experimental conditions, NaV1.6 knockdown did not prevent or strongly alter single evoked action potentials, unlike previous less specific methods used to block spontaneous activity. NaV1.6 knockdown also reduced pain behaviors in another pain model, chronic constriction of the sciatic nerve, provided the model was modified so that the lesion site was relatively close to the siRNA-injected lumbar DRGs. The results highlight the relative importance of abnormal spontaneous activity in establishing both pain behaviors and sympathetic sprouting, and suggest that the NaV1.6 isoform may have value as a therapeutic target. PMID:25686526

Xie, W; Strong, J A; Zhang, J-M

2015-04-16

281

Exact Green's function for a multiorbital Anderson impurity at high bias voltages  

NASA Astrophysics Data System (ADS)

We study the nonequilibrium Keldysh Green's function for an N -orbital Anderson model at high bias voltages, extending a previous work which for the case only with the spin degrees of freedom N =2 to arbitrary N . Our approach uses an effective non-Hermitian Hamiltonian that is defined with respect to a Liouville-Fock space in the context of a thermal field theory. The result correctly captures the relaxation processes at high energies, and is asymptotically exact not only in the high bias limit, but also in the high-temperature limit at thermal equilibrium. We also present an explicit continued-fraction representation of the Green's function. It clearly shows that the imaginary part is recursively determined by the decay rate of intermediate states with at most N -1 particle-hole-pair excitations. These high bias properties follow from the conservations of a generalized charge and current in the Liouville-Fock space. We also examine temperature dependence of the spectral function in equilibrium, comparing the exact results with the numerical finite-T and analytical T ?? results of the noncrossing approximation.

Oguri, Akira; Sakano, Rui

2015-03-01

282

STS-107 Payload Commander Michael Anderson suits up for TCDT  

NASA Technical Reports Server (NTRS)

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. .

2002-01-01

283

STS-107 Payload Commander Michael Anderson checks equipment at SPACEHAB  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- STS-107 Payload Commander Michael Anderson checks equipment during training at SPACEHAB. STS-107 is a research mission. The primary payload is the first flight of the SHI Research Double Module (SHI/RDM). The experiments range from material sciences to life sciences (many rats). Also part of the payload is the Fast Reaction Experiments Enabling Science, Technology, Applications and Research (FREESTAR) that incorporates eight high priority secondary attached shuttle experiments. STS-107 is scheduled to launch July 11, 2002

2002-01-01

284

STS-118 Astronauts Rick Mastracchio and Clay Anderson Perform EVA  

NASA Technical Reports Server (NTRS)

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.

2007-01-01

285

The S=1 Underscreened Anderson Lattice model for Uranium compounds  

NASA Astrophysics Data System (ADS)

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.

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

2011-01-01

286

Price-Anderson Nuclear Safety Enforcement Program. 1996 Annual report  

SciTech Connect

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.

NONE

1996-01-01

287

Strong localization of photons in certain disordered dielectric superlattices  

Microsoft Academic Search

A new mechanism for strong Anderson localization of photons in carefully prepared disordered dielectric superlattices with an everywhere real positive dielectric constant is described. In three dimensions, two photon mobility edges separate high- and low-frequency extended states from an intermediate-frequency pseudogap of localized states arising from remnant geometric Bragg resonances. Experimentally observable consequences are discussed.

Sajeev John

1987-01-01

288

77 FR 67057 - CSX Transportation, Inc.-Discontinuance of Service Exemption-in Anderson County, TN  

Federal Register 2010, 2011, 2012, 2013, 2014

...Transportation, Inc.--Discontinuance of Service Exemption--in Anderson County, TN CSX Transportation, Inc. (CSXT) filed a verified...milepost 0AE 256.0 at the end of the track in Oak Ridge, Anderson County, Tenn. The line traverses United States Postal...

2012-11-08

289

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

ERIC Educational Resources Information Center

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…

American Psychologist, 2009

2009-01-01

290

The Innovation Butterfly E.G. Anderson Jr. The Innovation Butterfly  

E-print Network

. Innovation is Complex Innovation process has "lifelike behavior," much like the weather ­It can be stableThe Innovation Butterfly E.G. Anderson Jr. The Innovation Butterfly: Managing Emergent Risks & Opportunities During Distributed Innovation Edward G. Anderson Jr. University of Texas McCombs School Nitin R

Ghosh, Joydeep

291

Low temperature behavior of the thermopower in disordered systems near the Anderson transition  

E-print Network

Low temperature behavior of the thermopower in disordered systems near the Anderson transition C investigate the behavior of the thermoelectric power S in disordered systems close to the Anderson­type metal In this paper, we study the low temperature behavior of the thermoelectric power S in disordered systems near

Chemnitz, Technische Universität

292

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

Federal Register 2010, 2011, 2012, 2013, 2014

...sold by the Superintendent of Documents. Prices of new books are listed in the first FEDERAL...3150-AJ25 Inflation Adjustments to the Price-Anderson Act Financial Protection Regulations...standard deferred premiums specified in the Price-Anderson Act for inflation at least...

2013-07-12

293

The MITLL/AFRL MT System Wade Shen, Brian Delaney, and Tim Anderson  

E-print Network

The MITLL/AFRL MT System Wade Shen, Brian Delaney, and Tim Anderson MIT Lincoln Laboratory 244. WrightPatterson AFB, OH 45433 Timothy.Anderson@wpafb.af.mil Abstract The MITLL/AFRL MT system for SpeechtoSpeech MT applications. This paper will discuss the architecture of the MITLL/AFRL MT

294

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

NASA Technical Reports Server (NTRS)

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.

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

1994-01-01

295

VOLUME 89, NUMBER 4 P H Y S I C A L R E V I E W L E T T E R S 22 JULY 2002 Coherent X-Ray Raman Spectroscopy: A Nonlinear Local Probe for Electronic Excitations  

E-print Network

) Nonlinear x-ray four-wave mixing experiments are becoming feasible due to rapid advances in high harmonic- wave mixing process involving three incoming beams k1, v1 , (k2, v2), and k3, v3 to generate a signal Spectroscopy: A Nonlinear Local Probe for Electronic Excitations Satoshi Tanaka1,3 and Shaul Mukamel1,2 1

Mukamel, Shaul

296

Adult versus Pediatric Neuroblastoma: The M.D. Anderson Cancer Center Experience  

PubMed Central

Background. Staging and treatment of adult neuroblastoma has yet to be formalized. We sought to determine the utility of the pediatric classification system in adults and determine the efficacy of different treatment modalities. Methods. Medical records of 118 adults (patients >17 years old) and 112 pediatric patients (ages 2–17), who were treated for neuroblastoma at M.D. Anderson Cancer Center from January 1994 to September 2012, were reviewed. International neuroblastoma risk group (INRG) variables were abstracted. The primary outcome of interest was actuarial progression-free survival. Results. Median age of pediatric patients was 5 years (range 3–16) and 47 years (range 18–82) for adult patients. There were no differences in PFS or OS between stage-matched risk categories between pediatric and adult patients (L1-P = 0.40, L2-P = 0.54, and M-P = 0.73). In the treatment of L1 disease, median PFS for adults treated with surgery and radiation was 11.1 months compared with single modality local treatment ± chemotherapy (6.4 and 5.1 months, resp.; P = 0.07). Median PFS in L2 adult patients was 5.2 months with local therapy and 4 months with the addition of chemotherapy (P = 0.23). Conclusions. Adult and pediatric patients with neuroblastoma achieve similar survival outcomes. INRG classification should be employed to stratify adult neuroblastoma patients and help select treatment. PMID:25024639

Conter, Henry J.; Ravi, Vinod; Ater, Joann L.; Araujo, Dejka M.

2014-01-01

297

Price-Anderson Nuclear Safety Enforcement Program. 1997 annual report  

SciTech Connect

This report summarizes activities in the Department of Energy's Price-Anderson Amendments Act (PAAA) Enforcement Program in calendar year 1997 and highlights improvements planned for 1998. The DOE Enforcement Program involves the Office of Enforcement and Investigation in the DOE Headquarters Office of Environment, Safety and Health, as well as numerous PAAA Coordinators and technical advisors in DOE Field and Program Offices. The DOE Enforcement Program issued 13 Notices of Violation (NOV`s) in 1997 for cases involving significant or potentially significant nuclear safety violations. Six of these included civil penalties totaling $440,000. Highlights of these actions include: (1) Brookhaven National Laboratory Radiological Control Violations / Associated Universities, Inc.; (2) Bioassay Program Violations at Mound / EG and G, Inc.; (3) Savannah River Crane Operator Uptake / Westinghouse Savannah River Company; (4) Waste Calciner Worker Uptake / Lockheed-Martin Idaho Technologies Company; and (5) Reactor Scram and Records Destruction at Sandia / Sandia Corporation (Lockheed-Martin).

NONE

1998-01-01

298

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

PubMed

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. PMID:23163470

2012-11-01

299

Localization of a Bose-Fermi mixture in a bichromatic optical lattice  

SciTech Connect

We study the localization of a cigar-shaped superfluid Bose-Fermi mixture in a quasiperiodic bichromatic optical lattice (OL) for interspecies attraction and intraspecies repulsion. The mixture is described by the Gross-Pitaevskii equation for the bosons, coupled to a hydrodynamic mean-field equation for fermions at unitarity. We confirm the existence of the symbiotic localized states in the Bose-Fermi mixture and Anderson localization of the Bose component in the interacting Bose-Fermi mixture on a bichromatic OL. The phase diagram in boson and fermion numbers showing the regions of the symbiotic and Anderson localization of the Bose component is presented. Finally, the stability of symbiotic and Anderson localized states is established under small perturbations.

Cheng Yongshan [Instituto de Fisica Teorica, UNESP - Universidade Estadual Paulista, 01.140-070, Sao Paulo, Sao Paulo (Brazil); Department of Physics, Hubei Normal University, 435002 Huangshi (China); Adhikari, S. K. [Instituto de Fisica Teorica, UNESP - Universidade Estadual Paulista, 01.140-070, Sao Paulo, Sao Paulo (Brazil)

2011-08-15

300

Infrared Divergence and Non-Fermi Liquid in Multichannel Degenerate Anderson Model  

NASA Astrophysics Data System (ADS)

As a straightforward extention of the study on infrared divergences in pseudo-particle spectra in the single-channel degenerate impurity Anderson model, those of the multichannel model are examined with use of the expansion from the large limit of the spin-orbital degeneracy N. Analysis with the most divergent terms in the expansion shows that exponents of spectra of the slave boson and the pseudo-fermion in the M-channel model with 1 ?M ?N are given respectively by 1-nf2M/N and (2nf-nf2)M/N, where nf is the average number of localized electrons at the impurity site. When M=1, the results recover those obtained earlier in the single channel model. In the limits, nf ?1 and M-2 ?1, these results tend to those obtained by the non-crossing approximation (NCA) study. It also shows that the scattering rate of the conduction electrons in the M-channel model includes infrared divergent terms proportional to (1-nf)(1-M-2) in contrast to the absence of infrared divergent terms in the single-channel model.

Tsuruta, Atsushi; ?no, Yoshiaki; Matsuura, Tamifusa; Kuroda, Yoshihiro

1997-11-01

301

The Nonlinear Dynamic Conversion of Analog Signals into Excitation Patterns  

E-print Network

Local periodic perturbations induce frequency-dependent propagation waves in an excitable spatio-temporally chaotic system. We show how segments of noise-contaminated and chaotic perturbations induce characteristic sequences of excitations in the model system. Using a set of tuned excitable systems, it is possible to characterize signals by their spectral composition of excitation pattern. As an example we analyze an epileptic spike-and-wave time series.

Gerold Baier; Markus Muller

2004-01-26

302

M.D. Anderson scientists identify a specialized regulatory T cell that stifles antibody production centers:  

Cancer.gov

A regulatory T cell that expresses three specific genes shuts down the mass production of antibodies launched by the immune system to attack invaders, a team led by scientists at The University of Texas MD Anderson Cancer Center reported...

303

MD Anderson studies find proton therapy treatment preserves quality of life for men with prostate cancer  

Cancer.gov

Two studies led by The University of Texas MD Anderson Cancer Center have found that proton therapy preserves the quality of life, specifically urinary and bowel function, in men treated with this targeted radiation modality for prostate cancer.

304

What Drives the Choice of a Third Party Logistics Provider? Edward Anderson , Tim Coltman*  

E-print Network

1 What Drives the Choice of a Third Party Logistics Provider? Edward Anderson , Tim Coltman of Economics and Business, University of Sydney, Australia Tim Coltman, Associate Professor, University Byron Keating, Associate Professor, University of Canberra, Australia *Corresponding author: Tim Coltman

Coltman, Tim

305

Taking on Titan: Meet Carrie Anderson - Duration: 2 minutes, 45 seconds.  

NASA Video Gallery

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...

306

Multipactor experiment on a dielectric surface R. B. Anderson, W. D. Getty,a)  

E-print Network

Multipactor experiment on a dielectric surface R. B. Anderson, W. D. Getty,a) M. L. Brake, Y. Y of excessive noise in communication sat- ellites, detuning of resonant cavities, and increased outgas- sing

Valfells, Ágúst

307

MD Anderson researchers find that cancer cells adapt energy needs to spread illness to other organs  

Cancer.gov

Scientists at The University of Texas MD Anderson Cancer Center have found that cancer cells traveling to other sites have different energy needs from their “stay-at-home” siblings which continue to proliferate at the original tumor site.

308

A guide to source materials of the life and work of Lawrence B. Anderson '30  

E-print Network

From 1933 to 1976, Professor Lawrence B. Anderson taught in the MIT Department of Architecture, and from 1947 to 1971, he served as its chairman and dean. Concurrently, from 1937 to 1972 , he was principal partner in the ...

Laguette, Victoria, 1953-

1998-01-01

309

MD Anderson study explains high platelets in ovarian cancer patients; survival reduced  

Cancer.gov

Highly elevated platelet levels fuel tumor growth and reduce the survival of ovarian cancer patients, an international team of researchers led by scientists at The University of Texas MD Anderson Cancer center reports in the New England Journal of Medicine.

310

MD Anderson study finds fetal exposure to radiation increases risk of testicular cancer  

Cancer.gov

Male fetuses of mothers that are exposed to radiation during early pregnancy may have an increased chance of developing testicular cancer, according to a study in mice at The University of Texas MD Anderson Cancer Center.

311

MD Anderson study finds biologic therapies for rheumatoid arthritis not associated with increased cancer risk  

Cancer.gov

Biologic therapies developed in the last decade for rheumatoid arthritis are not associated with an increased risk of cancer when compared with traditional treatments for the condition, according to new research from The University of Texas MD Anderson Cancer Center.

312

MD Anderson researchers find that drug combination acts against aggressive chronic lymphocytic leukemia  

Cancer.gov

A two-prong approach combining ibrutinib and rituximab (Rituxin) to treat aggressive chronic lymphocytic leukemia (CLL) produced responses with minor side effects in a Phase 2 clinical trial at The University of Texas MD Anderson Cancer Center.

313

MD Anderson researchers discover gene that might predict aggressive prostate cancer at diagnosis  

Cancer.gov

Researchers at The University of Texas MD Anderson Cancer Center have identified a biomarker living next door to the KLK3 gene that could predict which GS7 prostate cancer patients will have a more aggressive form of cancer.

314

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

Federal Register 2010, 2011, 2012, 2013, 2014

...TA-W-73,230; TA-W-73,230A] Plastic Omnium Automotive Exteriors, LLC, Anderson, SC; Plastic Omnium Automotive Exteriors, LLC, Troy...March 18, 2010, applicable to workers of Plastic Omnium Automotive Exteriors, LLC,...

2010-06-16

315

Collective Excitation and Stability of Flowing Gapless Fermi Superfluids  

NASA Astrophysics Data System (ADS)

We study the collective excitation and stability of superfluid Fermi gases flowing with a constant velocity in three-dimensional free space. In particular, we investigate a possible gapless superfluid state induced by the superflow using the mean-field theory and the generalized random-phase approximation (GRPA). For weak attractive interactions, we find that the mean-field superfluid order parameter takes a nonzero value even after the superflow velocity exceeds the threshold for the onset of Bogoliubov quasiparticle excitations. Since the Cooper pairs are only partially broken by the quasiparticle excitations, a gapless superfluid state can be formed over a certain range of superflow velocity above the pair-breaking onset. The GRPA excitation spectrum of the gapless superfluid state has a quasiparticle-quasihole continuum in addition to the usual quasiparticle-pair continuum and the Anderson-Bogoliubov collective mode. Moreover, the dynamic structure factor exhibits a characteristic peak structure in a long-wavelength and low-energy region of the quasiparticle-quasihole continuum. We find that the long-wavelength excitations eventually cause dynamical instability of the system when the superflow velocity further increases. As a result, the formation of a (dynamically stable) flowing gapless superfluid state is limited in a very narrow range of superflow velocity.

Yamamura, Hiroki; Yamamoto, Daisuke

2015-04-01

316

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

NASA Astrophysics Data System (ADS)

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.

Huang, Haiping; Kabashima, Yoshiyuki

2013-06-01

317

On Oscillators in Phyllosilicate Excitable Automata  

NASA Astrophysics Data System (ADS)

Phyllosilicate is a sheet of silicate tetrahedra bound by basal oxygens. A phyllosilicate excitable automaton is a regular network of finite state machines, which mimics structure of a silicate sheet. A node of the silicate sheet is an automaton, which takes resting, excited and refractory states, and updates its state in discrete time depending on a sum of excited states of its three (silicon automata) or six (oxygen automata) closest neighbors. Oscillator is a localized compact configuration of nonquiescent states which undergoes finite growth and modification but returns to its original state in a finite number of steps. We show that phyllosilicate excitable automata exhibit waves and oscillating localizations (oscillators) dynamics. Basic types of oscillators are classified and characterized.

Adamatzky, Andrew

2013-06-01

318

Continuously excited laser  

Microsoft Academic Search

There is disclosed continuously-excited lasers of the COâ mixing, and supersonic CO, types. There is specifically disclosed a method, and a laser apparatus, for producing a repetitively pulsed output, in which a stream of excited gas, of the type having a relatively long excitation life, is produced, stored and subsequently transferred, in the form of pulses, to a power extraction

R. C. McLeary; P. J. Beckwith

1984-01-01

319

DETERMINATION OF LOCAL MAGNITUDE, ML, FROM STRONG MOTION ACCELEROGRAMS  

Microsoft Academic Search

A technique is presented for determination of local magnitude, ML, from strong-motion accelerograms. The accelerograph records are used as an accel- eration input to the equation of motion of the Wood-Anderson torsion seismo- graph to produce a synthetic seismogram which is then read in the standard manner. When applied to 14 records from the San Fernando earthquake, the resulting ML

HIROO KANAMORI; PAUL C. JENNINGS

1978-01-01

320

Conductance noise in interacting Anderson insulators driven far from equilibrium  

NASA Astrophysics Data System (ADS)

The combination of strong disorder and many-body interactions in Anderson insulators leads to a variety of intriguing nonequilibrium transport phenomena. These include slow relaxation and a variety of memory effects characteristic of glasses. Here we show that when such systems are driven with sufficiently high current and in a liquid-helium bath, a peculiar type of conductance noise can be observed. This noise appears in the conductance versus time traces as downward-going spikes. The characteristic features of the spikes (such as typical width) and the threshold current at which they appear are controlled by the sample parameters. We show that this phenomenon is peculiar to hopping transport and does not exist in the diffusive regime. Observation of conductance spikes hinges also on the sample being in direct contact with the normal phase of liquid helium; when this is not the case, the noise exhibits the usual 1/f characteristics independent of the current drive. A model based on the percolative nature of hopping conductance explains why the onset of the effect is controlled by the current density. It also predicts the dependence on disorder as confirmed by our experiments. To account for the role of the bath, the hopping transport model is augmented by a heuristic assumption involving nucleation of cavities in the liquid helium in which the sample is immersed. The suggested scenario is analogous to the way high-energy particles are detected in a Glaser’s bubble chamber.

Orlyanchik, V.; Ovadyahu, Z.

2005-07-01

321

Parabolic Anderson model with a finite number of moving catalysts  

E-print Network

We consider the parabolic Anderson model (PAM) which is given by the equation $\\partial u/\\partial t = \\kappa\\Delta u + \\xi u$ with $u\\colon\\, \\Z^d\\times [0,\\infty)\\to \\R$, where $\\kappa \\in [0,\\infty)$ is the diffusion constant, $\\Delta$ is the discrete Laplacian, and $\\xi\\colon\\,\\Z^d\\times [0,\\infty)\\to\\R$ is a space-time random environment that drives the equation. The solution of this equation describes the evolution of a ``reactant'' $u$ under the influence of a ``catalyst'' $\\xi$. In the present paper we focus on the case where $\\xi$ is a system of $n$ independent simple random walks each with step rate $2d\\rho$ and starting from the origin. We study the \\emph{annealed} Lyapunov exponents, i.e., the exponential growth rates of the successive moments of $u$ w.r.t.\\ $\\xi$ and show that these exponents, as a function of the diffusion constant $\\kappa$ and the rate constant $\\rho$, behave differently depending on the dimension $d$. In particular, we give a description of the intermittent behavior of the sys...

Castell, Fabienne; Maillard, Grégory

2010-01-01

322

Trapping and steering on lattice strings: Virtual slow waves and directional and nonpropagating excitations.  

PubMed

Using a lattice string model, a number of peculiar excitation situations related to nonpropagating excitations and nonradiating sources are demonstrated. External fields can be used to trap excitations locally but also lead to the ability to steer such excitations dynamically as long as the steering is slower than the field's wave propagation. I present explicit constructions of a number of examples, including temporally limited nonpropagating excitations, directional excitation and virtually slowed propagation. Using these dynamical lattice constructions I demonstrate that neither persistent temporal oscillation nor static localization are necessary for nonpropagating excitations to occur. PMID:15244758

Essl, Georg

2004-06-01

323

Eternal inflation and localization on the landscape  

Microsoft Academic Search

We model essential features of eternal inflation on the landscape of a dense discretuum of vacua by the potential V(phi) = V0+deltaV(phi), where |deltaV(phi)| << V0 is random. We find that the diffusion of the distribution function rho(phi,t) of the inflaton expectation value in different Hubble patches may be suppressed due to the effect analogous to the Anderson localization in

Dmitry Podolsky; Kari Enqvist

2009-01-01

324

Clinical prodromes of neurodegeneration in Anderson-Fabry disease  

PubMed Central

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, ?-galactosidase deficiency in AFD is not associated with a typical cluster of clinical features prodromal for neurodegenerative diseases, such as Parkinson disease. PMID:25762709

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

2015-01-01

325

Anderson localization of ballooning modes, quantum chaos and the stability of compact quasiaxially symmetric stellarators  

E-print Network

, University of Wisconsin, Madison, WI 53706 R. L. Dewar Department of Theoretical Physics, The Australian to govern particle transport and system stability throughout mathematical physics (e.g., Noether's theorem3

Dewar, Robert L.

326

Noninvasive determination of local wavespeed and distensibility of the femoral artery by comb-excited Fourier velocity-encoded magnetic resonance imaging: Measurements on athletic and nonathletic human subjects  

Microsoft Academic Search

Summary The local distensibility of arteries is of interest because distensibility varies from artery to artery, may be altered by disease to different extents in different arteries, and may be modified by physiological or pharmacological means. Using magnetic resonance imaging (MRI) we have measured local arterial wavespeed in the femoral artery in healthy human subjects and calculated local arterial distensibility.

Maria Tarnawski; Gerard Cybulski; Denis Doorly; Charles Dumoulin; Robert Darrow; Colin Caro

1994-01-01

327

Using Diffusion Monte Carlo to Probe Rotational Excited States  

NASA Astrophysics Data System (ADS)

Since its inception in 1975 by Anderson, has been successfully applied to a wide range of electronic and vibrational problems. In the latter case, it has been shown to be a powerful method for studying highly fluxional systems exhibiting large amplitude vibrational motions. We report here our recent work developing a new DMC algorithm capable of treating rotational excited states. We first develop the appropriate coordinates, nodal structures, and re-crossing corrections for this problem. Then, using H_3O^+ and D_3O^+ as model systems, we show that our method can successfully describe a range of rotational states from mid0,0,0> to {1}/{?{2}} (mid10,10,0 > + mid 10,-10,0 >). In particular, we examine the combined effects of rotational and zero-point vibrational motion on the geometric structure of the molecules. Finally, we find the mid 10,0,0 > state to be somewhat problematic but show that the problem is straightforward to identify and has a well-defined solution. J. B. Anderson, J. Chem. Phys., 63, 1499 (1975). X. Huang, S. Carter, and J. Bowman, J. Chem. Phys., 118, 5431 (2003).

Petit, Andrew S.; McCoy, Anne B.

2009-06-01

328

Localization for transversally periodic random potentials on binary trees  

E-print Network

We consider a random Schr\\"odinger operator on the binary tree with a random potential which is the sum of a random radially symmetric potential, $Q_r$, and a random transversally periodic potential, $\\kappa Q_t$, with coupling constant $\\kappa$. Using a new one-dimensional dynamical systems approach combined with Jensen's inequality in hyperbolic space (our key estimate) we obtain a fractional moment estimate proving localization for small and large $\\kappa$. Together with a previous result we therefore obtain a model with two Anderson transitions, from localization to delocalization and back to localization, when increasing $\\kappa$. As a by-product we also have a partially new proof of one-dimensional Anderson localization at any disorder.

Richard Froese; Darrick Lee; Christian Sadel; Wolfgang Spitzer; Günter Stolz

2014-08-18

329

CONSTITUTIONAL LAW--Due Process and Equal Protection--Price-Anderson Act's $560,000,000 Limit on Liability From A nuclear Power Plant Accident Is Unconstitutional  

Microsoft Academic Search

Article summarizes Carolina Environmental Study Group v United States Atomic Energy Commission and congressional intent of the Price-Anderson Act. Article then speculates that the Price-Anderson Act will be found to be unconstitutional by the Supreme Court

Michael Fitzgerald

1978-01-01

330

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

USGS Publications Warehouse

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 of steam discharges from the Southeast Geysers. The hot spring waters are low in ions of Cl, B, and Li, but relatively high in HCO3, SO4 and NH4. The stable-isotope compositions (deuterium and oxygen-18) of these waters plot near the global meteoric water line. Geochemical data through time reveal apparent maxima in the concentrations of SO4, Fe, and Mn in 1991 to 1992, before the cluster became hotter. The black-to-gray deposits from the new spring cluster are rich in pyrite and contain anomalous metals. About one-half mile to the east of the hot springs, mineralized water discharges intermittently from an old adit of the Schwartz (Anderson) mine, and enters a tributary of Anderson Creek. This drainage increased substantially in July 1998, and a slurry of mine water and precipitates were transported down the tributary and into Anderson Creek. In December 1998, the adit water was 22°C, and had a chemical composition that was similar to spring waters that once discharged in the ravines surrounding the old Anderson Springs resort. The cause for the abrupt changes that have occurred in thermal features at Anderson Springs is still not resolved. One possibility is that these changes are a response to withdrawal of steam from The Geysers geothermal field over more than 20 years of production. Pressure declines in the geothermal reservoir may have caused a "drying out" of the overlying condensation zone. Induced boiling in this zone and upflow of deep steam to shallower depths would cause heating and vaporization of shallow ground waters. In addition, earthquakes occurring in the vicinity of Anderson Springs have increased significantly after nearby geothermal power plants began operation. These earthquakes may have enhanced surface discharge of thermal fluids along fractures and faults.

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

2000-01-01

331

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

PubMed

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. PMID:20027696

Hibberd, Fiona J

2009-10-01

332

R. E. Estell, E. L. Fredrickson, D. M. Anderson and M. D. Remmenga mixtures on alfalfa pellet intake by lambs  

E-print Network

R. E. Estell, E. L. Fredrickson, D. M. Anderson and M. D. Remmenga mixtures on alfalfa pellet and sesquiterpene mixtures on alfalfa pellet intake by lambs1 R. E. Estell,*2 E. L. Fredrickson,* D. M. Anderson. Four experiments were conducted to determine the effects of terpenes on intake of alfalfa pellets

333

A Knowledge Base for Dependability and Security Research H. Glaser, I. Millard, T. Anderson, Z. Andrews, J. Fitzgerald, B. Randell.  

E-print Network

COMPUTING SCIENCE A Knowledge Base for Dependability and Security Research H. Glaser, I. Millard, T Research Hugh Glaser, Ian Millard, Tom Anderson, Zoe Andrews, John Fitzgerald, Brian Randell. Abstract, Newcastle upon Tyne, NE1 7RU, England. #12;Bibliographical details GLASER, H., MILLARD, I., ANDERSON, T

Newcastle upon Tyne, University of

334

Long-distance indirect excitation of nanoplasmonic resonances.  

PubMed

In nanoscopic systems, size, geometry, and arrangement are the crucial determinants of the light-matter interaction and resulting nanoparticles excitation. At optical frequencies, one of the most prominent examples is the excitation of localized surface plasmon polaritons, where the electromagnetic radiation is coupled to the confined charge density oscillations. Here, we show that beyond direct near- and far-field excitation, a long-range, indirect mode of particle excitation is available in nanoplasmonic systems. In particular, in amorphous arrays of plasmonic nanodiscs we find strong collective and coherent influence on each particle from its entire active neighborhood. This dependency of the local field response on excitation conditions at distant areas brings exciting possibilities to engineer enhanced electromagnetic fields through controlled, spatially configured illumination. PMID:21650156

Khunsin, Worawut; Brian, Björn; Dorfmüller, Jens; Esslinger, Moritz; Vogelgesang, Ralf; Etrich, Christoph; Rockstuhl, Carsten; Dmitriev, Alexandre; Kern, Klaus

2011-07-13

335

Long-Distance Indirect Excitation of Nanoplasmonic Resonances  

PubMed Central

In nanoscopic systems, size, geometry, and arrangement are the crucial determinants of the light-matter interaction and resulting nanoparticles excitation. At optical frequencies, one of the most prominent examples is the excitation of localized surface plasmon polaritons, where the electromagnetic radiation is coupled to the confined charge density oscillations. Here, we show that beyond direct near- and far-field excitation, a long-range, indirect mode of particle excitation is available in nanoplasmonic systems. In particular, in amorphous arrays of plasmonic nanodiscs we find strong collective and coherent influence on each particle from its entire active neighborhood. This dependency of the local field response on excitation conditions at distant areas brings exciting possibilities to engineer enhanced electromagnetic fields through controlled, spatially configured illumination. PMID:21650156

2011-01-01

336

Supersolitons: Solitonic Excitations in Atomic Soliton Chains  

SciTech Connect

We show that, by tuning interactions in nonintegrable vector nonlinear Schroedinger equations modeling Bose-Einstein condensates and other relevant physical systems, it is possible to achieve a regime of elastic particlelike collisions between solitons. This would allow one to construct a Newton's cradle with solitons and supersolitons: localized collective excitations in solitary-wave chains.

Novoa, David; Michinel, Humberto [Area de Optica, Facultade de Ciencias, Universidade de Vigo, As Lagoas s/n, Ourense, E-32004 Spain (Spain); Malomed, Boris A. [Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978 (Israel); Perez-Garcia, Victor M. [Departamento de Matematicas, E.T.S.I. Industriales, and Instituto de Matematica Aplicada a la Ciencia y la Ingenieria, Universidad de Castilla-La Mancha, Avenida Camilo Jose Cela, 3, 13071 Ciudad Real (Spain)

2008-10-03

337

8. POWERHOUSE INTERIOR SHOWING EXCITER No. 1 IN FOREGROUND, EXCITER ...  

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

8. POWERHOUSE INTERIOR SHOWING EXCITER No. 1 IN FOREGROUND, EXCITER No. 2., AND GENERATOR UNITS BEHIND EXCITER No. 2 IN BACKGROUND. EXCITER No. 1 GENERATOR HAS A COVER OVER TOP HALF OF COMMUTATOR ELEMENT. VIEW TO NORTHWEST. - Rush Creek Hydroelectric System, Powerhouse Exciters, Rush Creek, June Lake, Mono County, CA

338

Magnetoplasmon excitations in arrays of circular and noncircular quantum dots  

Microsoft Academic Search

We have investigated the magnetoplasmon excitations in arrays of circular and noncircular quantum dots within the Thomas-Fermi-Dirac-von Weizsäcker approximation. Deviations from the ideal collective excitations of isolated parabolically confined electrons arise from local perturbations of the confining potential as well as interdot Coulomb interactions. The latter are unimportant unless the interdot separations are of the order of the size of

B. P. van Zyl; E. Zaremba; D. A. W. Hutchinson

2000-01-01

339

LEGO MindStorms: Not Just for K-12 Anymore Frank Klassner, Scott D. Anderson  

E-print Network

LEGO MindStorms: Not Just for K-12 Anymore Frank Klassner, Scott D. Anderson Department the possibility of using the Lego Mindstorms robots to support the ACM Computing Curriculum 2001, using them 2001, curriculum development, robotics, Lego Mindstorms Introduction The fields of Robotics

Klassner, Frank

340

MD Anderson develops prognostic model for MDS related to prior cancer therapy  

Cancer.gov

A large-scale analysis of patients whose myelodysplastic syndrome is related to earlier cancer treatment overturns the notion that all of them have a poor prognosis, researchers from the University of Texas MD Anderson Cancer Center report at the 53rd Annual Meeting of the American Society of Hematology.

341

MD Anderson study finds everolimus prolongs progression-free survival for patients with neuroendocrine tumors:  

Cancer.gov

Combination treatment with everolimus, an inhibitor of the mammalian target rapamycin (mTOR), and octreotide has shown to improve progression-free survival for patients with advanced neuroendocrine tumors and a history of carcinoid syndrome, according to researchers at The University of Texas MD Anderson Cancer Center.

342

Study led by MD Anderson scientists identifies prostate cancer stem cells among low-PSA cells  

Cancer.gov

Prostate cancer cells that defy treatment and display heightened tumor-generating capacity can be identified by levels of prostate specific antigen (PSA) expressed in the tumor cells, a research team led by scientists at The University of Texas MD Anderson Cancer Center reports in the May 3 edition of Cell Stem Cell.

343

MD Anderson study finds inflammatory mediator promotes colorectal cancer by stifling protective genes:  

Cancer.gov

Chronic inflammation combines with DNA methylation, a process that shuts down cancer-fighting genes, to promote development of colorectal cancer, scientists at The University of Texas MD Anderson Cancer Center report today in the advance online publication of the journal Nature Medicine.

344

MD Anderson study finds tamoxifen causes significant side effects in male breast cancer patients:  

Cancer.gov

About half of male breast cancer patients who take the drug tamoxifen to prevent their disease from returning report side effects such as weight gain and sexual dysfunction, which prompts more than 20 percent of them to discontinue treatment, according to researchers at The University of Texas MD Anderson Cancer Center.

345

M.D. Anderson study finds previously unconnected molecular networks conspire to promote cancer:  

Cancer.gov

An inflammation-promoting protein triggers deactivation of a tumor-suppressor that usually blocks cancer formation via the NOTCH signaling pathway, a team of researchers led by scientists at The University of Texas M.D. Anderson Cancer Center reports today in Molecular Cell.

346

UT MD Anderson study finds metabolic protein plays unexpected role in tumor cell formation and growth:  

Cancer.gov

The embryonic enzyme pyruvate kinase M2 (PKM2) has a well-established role in metabolism and is highly expressed in human cancers. Now, a team led by researchers at The University of Texas MD Anderson Cancer Center reports in advance online publication of the journal Nature that PKM2 has important non-metabolic functions in cancer formation.

347

Decadal climate cycles and declining Columbia River salmon James J. Anderson  

E-print Network

1 Decadal climate cycles and declining Columbia River salmon James J. Anderson School of Fisheries - This paper explores the effects of the interaction of anthropogenic trends and climate cycles on salmon river salmon production resulted from the interactions of human activities and climatic regime shifts

Washington at Seattle, University of

348

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

ERIC Educational Resources Information Center

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 inquiry" which has a positive influence on…

Jezegou, Annie

2010-01-01

349

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

ERIC Educational Resources Information Center

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…

American Psychologist, 2012

2012-01-01

350

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

NASA Technical Reports Server (NTRS)

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.

Neal, Henry L.

1991-01-01

351

CO2 Mitigation Costs for Canada and the Alberta Oil Sands Justin David Anderson  

E-print Network

CO2 Mitigation Costs for Canada and the Alberta Oil Sands By Justin David Anderson Bachelor. Impact and cost assessments aim to alleviate some of these difficulties by attempting to treat the costs individually to estimate costs associated with different regulations since across regions the impacts from

352

Counting statistics for the Anderson impurity model: Bethe ansatz and Fermi liquid study  

Microsoft Academic Search

We study the counting statistics of charge transport in the Anderson impurity model (AIM) employing both Keldysh perturbation theory in a Fermi liquid picture and the Bethe ansatz. In the Fermi liquid approach, the object of our principal interest is the generating function for the cumulants of the charge current distribution. We derive an exact analytic formula relating the full

A. O. Gogolin; R. M. Konik; A. W. W. Ludwig; H. Saleur

2007-01-01

353

Plate Tectonics as a Far-From-Equilibrium Self-Organized System Don L. Anderson  

E-print Network

Plate Tectonics as a Far- From- Equilibrium Self-Organized System By Don L. Anderson Word Count: 3 and other forces at the top. Plate tectonics was once regarded as passive motion of plates on top of mantle convection cells but it now appears that continents and plate tectonics organize the flow in the mantle

Anderson, Don L.

354

CAPSTONE PROJECTS AS COMMUNITY CONNECTORS Ruth E. Anderson, Gaetano Borriello, Hlne Martin  

E-print Network

learned. INTRODUCTION Course projects based on real-world needs can serve as the basis for an engagingCAPSTONE PROJECTS AS COMMUNITY CONNECTORS Ruth E. Anderson, Gaetano Borriello, Hélène Martin and faculty at Heritage University to create an on-line store for marketing crafts made by artists in rural

Anderson, Richard

355

Shouting to be Heard in Advertising Simon P. Anderson and Andr de Palma  

E-print Network

Shouting to be Heard in Advertising Simon P. Anderson and André de Palma July 2011 revised October 2012 Abstract Advertising competes for scarce consumer attention, so more profitable advertisers send of loud shouters or large range of quiet whisperers. All advertisers prefer there to be less shouting

Paris-Sud XI, Université de

356

PLAYING SMART ANOTHER LOOK AT ARTIFICIAL INTELLIGENCE IN COMPUTER GAMES Eike F Anderson  

E-print Network

1 PLAYING SMART ­ ANOTHER LOOK AT ARTIFICIAL INTELLIGENCE IN COMPUTER GAMES Eike F Anderson12 5BB, UK E-mail: eanderson@bournemouth.ac.uk KEYWORDS artificial intelligence, computer games, non intelligence in general and artificial intelligence in the context of its use in modern computer games

Davies, Christopher

357

A Novel Low-Power FPGA Routing Switch Jason H. Anderson and Farid N. Najm  

E-print Network

A Novel Low-Power FPGA Routing Switch Jason H. Anderson and Farid N. Najm Department of Electrical FPGA routing switch that can operate in three different modes: high-speed, low-power or sleep. High in industrial FPGA designs. Specifi- cally, we show that a considerable fraction of routing switches may

Najm, Farid N.

358

Yield maps for nanoscale metallic multilayers Adrienne V. Lamm *, Peter M. Anderson  

E-print Network

Yield maps for nanoscale metallic multilayers Adrienne V. Lamm *, Peter M. Anderson Department for the macroscopic, in-plane, bi-axial tension to macroscopically yield a nanoscale multilayered thin film consisting mismatch on the macroscopic yield strength of metallic multilayer thin films. This will be accomplished

Anderson, Peter M.

359

SILK { a playful blend of Scheme and Java Kenneth R. Anderson, BBN Technologies, Cambridge, MA  

E-print Network

. Java pro- vides standard libraries that support web programming. It has the goal of being portableSILK { a playful blend of Scheme and Java Kenneth R. Anderson, BBN Technologies, Cambridge, MA sym- bols: (loop (print (eval (read)))) Consider what we would have to do to write a Lisp (or Java

Strickland, Stevie

360

Main-Chain Conformational Tendencies of Amino Acids Robert J. Anderson,1,2  

E-print Network

Main-Chain Conformational Tendencies of Amino Acids Robert J. Anderson,1,2 Zhiping Weng,2 Robert K tendencies of an amino acid. Despite forty years of research, the shape of Ramachandran plots is still tendencies among amino acids, and showed that the conformational relationships of amino ac- ids are well

Weng, Zhiping

361

MD Anderson study finds that AML patients have high response rate with Vorinostat added to treatment  

Cancer.gov

Adding a drug that activates genes to frontline combination therapy for acute myeloid leukemia resulted in an 85 percent remission rate after initial treatment, researchers at The University of Texas MD Anderson Cancer Center reported at the 53rd Annual Meeting of the American Society of Hematology.

362

AUTO ANSWER CIRCUIT DESIGN FOR AN ANDERSON JACOBSON AD 342 MODEM  

EPA Science Inventory

The report describes a circuit which connects a Western Electric Model 1001F Data Accessing Arrangement to an Anderson Jacobson Model AD 342 Modem. It automatically answers the phone and holds a data connection as long as a received carrier is present. It self resets upon loss of...

363

MD Anderson study finds ovarian cancer patients survive longer with BRCA2 mutated in tumors:  

Cancer.gov

Women with high-grade ovarian cancer live longer and respond better to platinum-based chemotherapy when their tumors have BRCA2 genetic mutations, researchers at The University of Texas MD Anderson Cancer Center and the Institute for Systems Biology report in the Oct. 12 issue of the Journal of the American Medical Association.

364

JILL T. ANDERSON Department of Ecology and Evolutionary Biology Telephone: 773-255-1996  

E-print Network

): Social behavior of capuchin monkeys (Cebus capuchinus). 1998-2000 Plant taxonomist and research assistant. 2006-2008 National Science Foundation Doctoral Dissertation Improvement Grant. Evolution of plant 447: 775. POSTERS AND PRESENTATIONS Anderson, J.T., 2007. Evolution of a native blueberry (Vaccinium

Geber, Monica A.

365

UT MD Anderson study finds advances in breast cancer don't extend to older women:  

Cancer.gov

The survival rates for older women with breast cancer lag behind younger women diagnosed with the disease, indicating that the elder population may be missing out on improvements in treatment and detection, according to new research from The University of Texas MD Anderson Cancer Center.

366

PDF tails and self-organization of shear flows Johan Anderson  

E-print Network

results · Instanton method · Coherent structures · Model equations + instanton solutions · Model of shearPDF tails and self-organization of shear flows Johan Anderson Department of Applied Mathematics, but large amplitude (e.g. large heat load on the wall.) Radial velocity PDF measured at TCV, Garcia EPS2006

367

Potential energy surface for the hydrogen-iodine reaction James B. Anderson  

E-print Network

Potential energy surface for the hydrogen-iodine reaction James B. Anderson Department of Chemistry valenceelectronsand with effectivepotentials for the iodine core electrons.The favored pathway for the overall-H-H-I. The pathway is accessibleto bound and unbound iodine atom pairs and it allows the bimolecular and termolecular

Anderson, James B.

368

MD Anderson study identifies novel therapeutic targets for small cell lung cancer  

Cancer.gov

Newly discovered molecular differences between small cell lung cancer and non-small cell lung cancer have revealed PARP1 and EZH2 as potential therapeutic targets for patients with small cell lung cancer, according to the results of a University of Texas MD Anderson study published in Cancer Discovery, a journal of the American Association for Cancer Research.

369

Bio390 Glucose and the Kidney ANSWERS thanks to Dr. J.F. Anderson,  

E-print Network

is freely filterable the amount that is filtered is a function of the GFR and its concentration in the blood1 Bio390 Glucose and the Kidney ANSWERS thanks to Dr. J.F. Anderson, Dept Zoology Univ of Florida of urine formation: 1.0 ml min plasma glucose concentration: 80 mg 100 ml plasma urine glucose

Prestwich, Ken

370

Relativistic ionized gases: Ohm and Fourier laws from Anderson and Witting model equation  

Microsoft Academic Search

The relativistic laws of Ohm and Fourier are determined for binary mixtures of electrons with protons or photons subjected to external electromagnetic fields, by using the Anderson and Witting model equation. General expressions for the electrical and thermal conductivities for relativistic degenerate ionized gas mixtures are determined and explicit expressions for the transport coefficients are given for the particular cases:

G. M. Kremer; C. H. Patsko

2003-01-01

371

MD Anderson study finds telomere failure, telomerase activation drive prostate cancer progression  

Cancer.gov

Genomic instability caused by an erosion of the protective caps on chromosomes, followed by activation of an enzyme that reinforces those caps, allows malignant cells to evade destruction and acquire more deadly characteristics, MD Anderson Cancer Center researchers report in an Online Now article at the journal Cell.

372

MD Anderson researchers compare treatments, survival benefits for early-stage lung cancer  

Cancer.gov

Removal of the entire lobe of lung may offer patients with early-stage lung cancer better overall survival when compared with a partial resection, and stereotactic ablative radiotherapy (SABR) may offer the same survival benefit as a lobectomy for some patients, according to a study from The University of Texas MD Anderson Cancer Center.Click here to read the full press release.

373

A Genetic Algorithm for Evolving Stochastic Context-Free James Anderson, Joe Staines & Paula Tataru  

E-print Network

A Genetic Algorithm for Evolving Stochastic Context-Free Grammars James Anderson, Joe Staines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 3.1.1 Modifications to the Grammar Structure . . . . . . . . . . . . . . . . . . . . . 15 3.5 Modification to CYK and Inside/Outside Algorithms . . . . . . . . . . . . . . . . . . 23 3.5.1 CYK Algorithm

Goldschmidt, Christina

374

Assessment of the risk of pile driving to juvenile fish James J. Anderson  

E-print Network

page 1 Assessment of the risk of pile driving to juvenile fish James J. Anderson Fisheries Research-12, 1990, Seattle, WA. The problem In this talk I will report on an effort to reassess the risk of pile industry concerns that provisions restricting pile driving during the spring migration are resulting

Washington at Seattle, University of

375

Low-Power Programmable Routing Circuitry for FPGAs Jason H. Anderson  

E-print Network

generations. Subthreshold leakage current flows between the source and drain termi- nals of an OFF MOSLow-Power Programmable Routing Circuitry for FPGAs Jason H. Anderson Department of ECE University designs that are programmable to operate in three different modes: high- speed, low-power or sleep. High

Najm, Farid N.

376

RMP Colloquia The role of the Josephson-Anderson equation in superfluid helium*  

E-print Network

a simple equation describing the time evolution of a superfluid's quantum phase can be used as a powerful vortex motion. The equation has been used to simplify the understanding of new phenomena, such as vortex of the phase evolution equation, introduced by Josephson and developed further by Anderson. The utility

Packard, Richard E.

377

Real-Time Character Animation for Computer Games Eike F Anderson  

E-print Network

Real-Time Character Animation for Computer Games Eike F Anderson National Centre for Computer Animation Bournemouth University ABSTRACT The importance of real-time character animation in computer games is continuously growing. This paper will present and discuss various methods of 3D character animation

Davies, Christopher

378

Inference of Tamoxifen's Effects on Prevention of Breast U T M. D. Anderson Cancer Center  

E-print Network

Inference of Tamoxifen's Effects on Prevention of Breast Cancer by Yu Shen U T M. D. Anderson to breast cancer. We propose a flexible semiparametric model to assess the effects of tamoxifen Cancer Center Department of Biostatistics, Unit 1411 1515 Holcombe Blvd, Houston, TX 77030 EMAIL yshen

Jin, Jiashun

379

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

ERIC Educational Resources Information Center

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,…

Bullen, Elizabeth; Parsons, Elizabeth

2007-01-01

380

Enzyme replacement therapy in Anderson-Fabry's disease: beneficial clinical effect on vital organ function  

Microsoft Academic Search

Two recent randomized trials pointed out the bene- ficial effect of enzyme replacement therapy on bio- chemical parameters in patients with Anderson-Fabry's disease. Clinical end-points, such as amelioration or stabilization of renal function deterioration, or improve- ment of left ventricular hypertrophy have not been evaluated in depth. We report the case of a patient whose moderately impaired renal function was

Dominique Chauveau; Jean-Pierre Grunfeld

381

A Limit Study of JavaScript Parallelism Emily Fortuna Owen Anderson Luis Ceze Susan Eggers  

E-print Network

A Limit Study of JavaScript Parallelism Emily Fortuna Owen Anderson Luis Ceze Susan Eggers Computer on the potential parallelism of JavaScript appli- cations, including popular web pages and standard JavaScript benchmarks. We examine dependency types and looping behavior to better understand the potential for JavaScript

Anderson, Richard

382

MD Anderson-led preclinical research shows normal gene hinders breast cancer chemotherapy  

Cancer.gov

Presence of normal p53, a tumor suppressor gene, instead of a mutated version, makes breast cancer chemotherapy with doxorubicin less effective. The preclinical study led by MD Anderson scientists was published today in the journal Cancer Cell. The research, which challenges the existing paradigm, is another step closer to personalized cancer medicine for breast cancer.

383

MD Anderson-led study finds two targeted therapies act against Ewing's sarcoma tumors  

Cancer.gov

A pair of targeted therapies shrank tumors in some patients with treatment-resistant Ewing's sarcoma or desmoplastic small-round-cell tumors, according to research led by investigators from The University of Texas MD Anderson Cancer Center reported at the American Association for Cancer Research Annual Meeting 2012.

384

MD Anderson scientists discover marker to identify, attack breast cancer stem cells  

Cancer.gov

Breast cancer stem cells wear a cell surface protein that is part nametag and part bull’s eye, identifying them as potent tumor-generating cells and flagging their vulnerability to a drug, researchers at The University of Texas MD Anderson Cancer Center report online in Journal of Clinical Investigation.

385

MD Anderson study finds gene therapy kills breast cancer stem cells, boosts chemotherapy:  

Cancer.gov

Gene therapy delivered directly to a particularly stubborn type of breast cancer cell causes the cells to self-destruct, lowers the chance of recurrence and helps increase the effectiveness of some types of chemotherapy, researchers at The University of Texas MD Anderson Cancer Center reported in the Sept. 13 edition of Cancer Cell.

386

MOOD: A Concurrent C++-Based Music Language David Anderson Jeff Bilmes  

E-print Network

are applied going up the tree. Thus the time values (lengths of notes and rests) generated by a NP, time shifting, and tempo. Some of these classes are simple objects (e.g., adding a constant to volumeMOOD: A Concurrent C++-Based Music Language David Anderson Jeff Bilmes

Noble, William Stafford

387

On the Stability of Web Crawling and Web Reid Anderson1  

E-print Network

On the Stability of Web Crawling and Web Search Reid Anderson1 , Christian Borgs1 , Jennifer Chayes moti- vated by web crawling. We introduce a notion of stable cores, which is the set of web pages that are usually contained in the crawling buffer when the buffer size is smaller than the total number of web

Chaudhuri, Surajit

388

ANALYSIS OF SOME PHYSICAL PROPERTIES OF CERIUM COMPOUNDS IN THE ANDERSON MODEL  

E-print Network

E 1105 ANALYSIS OF SOME PHYSICAL PROPERTIES OF CERIUM COMPOUNDS IN THE ANDERSON MODEL P the theory of Lacroix-Lyon-Caen et al., who have calculated the magnetic susceptibility of a cerium Kondo of the exchange parameter 0393n(EF) and the Kondo temperature TK of some cerium compounds from susceptibility

Paris-Sud XI, Université de

389

Band of localized electromagnetic waves in random arrays of dielectric cylinders Marian Rusek, Arkadiusz Orlowski, and Jan Mostowski  

E-print Network

Band of localized electromagnetic waves in random arrays of dielectric cylinders Marian Rusek­668 Warszawa, Poland Received 6 February 1997 Anderson localization of electromagnetic waves in random arrays- ies. Electromagnetic waves propagating in these structures mimic, to reasonable extent, the behavior

Rusek, Marian

390

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

SciTech Connect

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.

Meuleman, G. Allyn

1987-06-01

391

Localized and Extended States in a Disordered Trap  

SciTech Connect

We study Anderson localization in a disordered potential combined with an inhomogeneous trap. We show that the spectrum displays both localized and extended states, which coexist at intermediate energies. In the region of coexistence, we find that the extended states result from confinement by the trap and are weakly affected by the disorder. Conversely, the localized states correspond to eigenstates of the disordered potential, which are only affected by the trap via an inhomogeneous energy shift. These results are relevant to disordered quantum gases and we propose a realistic scheme to observe the coexistence of localized and extended states in these systems.

Pezze, Luca; Sanchez-Palencia, Laurent [Laboratoire Charles Fabry de l'Institut d'Optique, CNRS and Univ. Paris-Sud, Campus Polytechnique, RD 128, F-91127 Palaiseau cedex (France)

2011-01-28

392

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

NASA Astrophysics Data System (ADS)

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.

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

2013-03-01

393

MD Anderson researchers reveal genomic diversity of individual lung tumors  

Cancer.gov

Known cancer-driving genomic aberrations in localized lung cancer appear to be so consistently present across tumors that a single biopsy of one region of the tumor is likely to identify most of them, according to a paper published today in Science.

394

Excitation energy relaxation in model aggregates of photosynthetic pigments upon picosecond laser excitation  

NASA Astrophysics Data System (ADS)

The methods of picosecond absorption spectroscopy require theuse of sufficiently high laser pulse intensities because of low sensitivity of these methods. The excitation of aggregated systems containing a large number of interacting chromophores, localized in a small volume, by intense laser pulses may lead to side effects which are observed as changes in absorption spectra but are not connected with the processes of electronic excitation energy relaxation. In this paper we present the results of such investigations through the examples of polymer ordered aggregates of photosynthetic pigments (chlorophyll, protochlorophyll, pheophytin) in binary mixtures of water with organic solvent (T=293 K) upon excitation by 20 ps pulses. The observable reversible spectral changes in ps and ns time scales are attributed to the effects of laser heating, rather than to the population of aggregate excited electronic states.

Chirvony, Vladimir S.; Zenkevich, Eduard I.; Gadonas, Roaldas; Krasauskas, V.; Pelakauskas, A.

1991-05-01

395

Impurities and electronic localization in graphene bilayers  

NASA Astrophysics Data System (ADS)

We analyze the electronic properties of bilayer graphene with Bernal stacking and a low concentration of adatoms. Assuming that the host bilayer lies on top of a substrate, we consider the case where impurities are adsorbed only on the upper layer. We describe nonmagnetic impurities as a single orbital hybridized with carbon's pz states. The effect of impurity doping on the local density of states with and without a gated electric field perpendicular to the layers is analyzed. We look for Anderson localization in the different regimes and estimate the localization length. In the biased system, the field-induced gap is partially filled by strongly localized impurity states. Interestingly, the structure, distribution, and localization length of these states depend on the field polarization.

Ojeda Collado, H. P.; Usaj, Gonzalo; Balseiro, C. A.

2015-01-01

396

Testing the excitability of human motoneurons  

PubMed Central

The responsiveness of the human central nervous system can change profoundly with exercise, injury, disuse, or disease. Changes occur at both cortical and spinal levels but in most cases excitability of the motoneuron pool must be assessed to localize accurately the site of adaptation. Hence, it is critical to understand, and employ correctly, the methods to test motoneuron excitability in humans. Several techniques exist and each has its advantages and disadvantages. This review examines the most common techniques that use evoked compound muscle action potentials to test the excitability of the motoneuron pool and describes the merits and limitations of each. The techniques discussed are the H-reflex, F-wave, tendon jerk, V-wave, cervicomedullary motor evoked potential (CMEP), and motor evoked potential (MEP). A number of limitations with these techniques are presented. PMID:23630483

McNeil, Chris J.; Butler, Jane E.; Taylor, Janet L.; Gandevia, Simon C.

2013-01-01

397

Shear layer excitation, experiment versus theory  

NASA Technical Reports Server (NTRS)

The acoustical excitation of shear layers is investigated. Acoustical excitation causes the so-called orderly structures in shear layers and jets. Also, the deviations in the spreading rate between different shear layer experiments are due to the same excitation mechanism. Measurements in the linear interaction region close to the edge from which the shear layer is shed are examined. Two sets of experiments (Houston 1981 and Berlin 1983/84) are discussed. The measurements were carried out with shear layers in air using hot wire anemometers and microphones. The agreement between these measurements and the theory is good. Even details of the fluctuating flow field correspond to theoretical predictions, such as the local occurrence of negative phase speeds.

Bechert, D. W.; Stahl, B.

1984-01-01

398

Excitation Methods for Bridge Structures  

SciTech Connect

This paper summarizes the various methods that have been used to excited bridge structures during dynamic testing. The excitation methods fall into the general categories of ambient excitation methods and measured-input excitation methods. During ambient excitation the input to the bridge is not directly measured. In contrast, as the category label implies, measured-input excitations are usually applied at a single location where the force input to the structure can be monitored. Issues associated with using these various types of measurements are discussed along with a general description of the various excitation methods.

Farrar, C.R.; Duffy, T.A.; Cornwell, P.J.; Doebling, S.W.

1999-02-08

399

Exciting flavored bound states  

NASA Astrophysics Data System (ADS)

We study ground and radial excitations of flavor singlet and flavored pseudoscalar mesons within the framework of the rainbow-ladder truncation using an infrared massive and finite interaction in agreement with recent results for the gluon-dressing function from lattice QCD and Dyson-Schwinger equations. Whereas the ground-state masses and decay constants of the light mesons as well as charmonia are well described, we confirm previous observations that this truncation is inadequate to provide realistic predictions for the spectrum of excited and exotic states. Moreover, we find a complex conjugate pair of eigenvalues for the excited D(s) mesons, which indicates a non-Hermiticity of the interaction kernel in the case of heavy-light systems and the present truncation. Nevertheless, limiting ourselves to the leading contributions of the Bethe-Salpeter amplitudes, we find a reasonable description of the charmed ground states and their respective decay constants.

Rojas, E.; El-Bennich, B.; de Melo, J. P. B. C.

2014-10-01

400

Exciting flavored bound states  

E-print Network

We study ground and radial excitations of flavor singlet and flavored pseudoscalar mesons within the framework of the rainbow-ladder truncation using an infrared massive and finite interaction in agreement with recent results for the gluon-dressing function from lattice QCD and Dyson-Schwinger equations. Whereas the ground-state masses and decay constants of the light mesons as well as charmonia are well described, we confirm previous observations that this truncation is inadequate to provide realistic predictions for the spectrum of excited and exotic states. Moreover, we find a complex conjugate pair of eigenvalues for the excited $D_{(s)}$ mesons, which indicates a non-Hermiticity of the interaction kernel in the case of heavy-light systems and the present truncation. Nevertheless, limiting ourselves to the leading contributions of the Bethe-Salpeter amplitudes, we find a reasonable description of the charmed ground states and their respective decay constants.

E. Rojas; B. El-Bennich; J. P. B. C. de Melo

2014-10-23

401

Localized description of band structure effects on Li atom interaction with graphene  

Microsoft Academic Search

We study theoretically the localized aspects of the interaction between an Li atom and graphene. To this end, we use an ab initio calculation of the Hamiltonian terms within the Anderson model that allows us to take into account the chemical properties of Li and C atoms and the two-dimensional band structure of graphene. In this way, physical magnitudes of

Marcelo A. Romero; A. Iglesias-García; E. C. Goldberg

2011-01-01

402

On the Aggregation of Local Risk Models for Global Risk Management  

E-print Network

On the Aggregation of Local Risk Models for Global Risk Management Greg Anderson Vice President: portfolio risk, total risk, optimization, positive definite. 2 #12;1 Introduction Portfolio managers is a revised version of an article written in 2003 under the title "Forecasting Total Risk". #12;Abstract Given

Aluffi, Paolo

403

A Finite Difference Domain Decomposition Method Using Local Corrections for the Solution of Poisson's Equation  

Microsoft Academic Search

We present a domain decomposition method for computing finite difference solutions to the Poisson equation with infinite domain boundary conditions. Our method is a finite difference analogue of Anderson's Method of Local Corrections. The solution is computed in three steps. First, fine-grid solutions are computed in parallel using infinite domain boundary conditions on each subdomain. Second, information is transferred globally

Gregory T. Balls; Phillip Colella

2002-01-01

404

MD Anderson researchers find that breast cancer spread may be tied to cells that regulate blood flow  

Cancer.gov

Scientists at the University of Texas MD Anderson Cancer Center believe that targeting blood vessel cells known as pericytes may offer a potential new therapeutic approach when combined with vascular growth factors responsible for cell death.

405

Ahn Stephen Alexander Kyle Allred WesleyAhn, Stephen Alexander, Kyle Allred, Wesley Anderson, Parker Antuma, Jesse Azeez, Karen  

E-print Network

Anderson, Parker Antuma, Jesse Azeez, Karen #12;B id Pi Baskerville Lizzy Bazan AlexandroBaidas, Piotr JSturges, Frank Talbot, Jacob Van De Winkle, Janet Vanleuven, Sheena Vaux, Kaitlyn Vayo II, Louis #12;Voce

Edwards, Paul N.

406

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

Federal Register 2010, 2011, 2012, 2013, 2014

...Board [Docket No. FD 35700] Chessie Logistics Co., LLC--Acquisition and Operation...Emil Anderson & Son, Inc. Chessie Logistics Co., LLC (Chessie), a noncarrier...Erbacher, Legal Counsel, Chessie Logistics Co., LLC, 1001 Green Bay Rd.,...

2012-12-06

407

Instability of insulating states in optical lattices due to collective phonon excitations  

NASA Astrophysics Data System (ADS)

The effect of collective phonon excitations on the properties of cold atoms in optical lattices is investigated. These phonon excitations are collective excitations, whose appearance is caused by intersite atomic interactions correlating the atoms, and they do not arise without such interactions. These collective excitations should not be confused with lattice vibrations produced by an external force. No such force is assumed. But the considered phonons are purely self-organized collective excitations, characterizing atomic oscillations around lattice sites, due to intersite atomic interactions. It is shown that these excitations can essentially influence the possibility of atoms' being localized. The states that would be insulating in the absence of phonon excitations can become delocalized when these excitations are taken into account. This concerns long-range as well as local atomic interactions. To characterize the region of stability, the Lindemann criterion is used.

Yukalov, V. I.; Ziegler, K.

2015-02-01

408

Effective models for Anderson impurity and Kondo problems from continuous unitary transformations  

NASA Astrophysics Data System (ADS)

The method of continuous unitary transformations (CUTs) is applied to the Anderson impurity and the Kondo model aiming at the systematic derivation of convergent effective models. If CUTs are applied in a conventional way, diverging differential equations occur. Similar to poor man's scaling, the energy scale, below which the couplings diverge, corresponds to the Kondo temperature TK. We present a way to apply CUTs to the Kondo and to the Anderson impurity model so that no divergences occur but a converged effective low-energy model is derived with small finite parameters at arbitrarily small energies. The ground state corresponds to a bound singlet with a binding energy given by the Kondo temperature TK.

Krones, Jörn; Uhrig, Götz S.

2015-03-01

409

Anderson's impurity-model analysis on CeO1-xFxBiS2  

NASA Astrophysics Data System (ADS)

We have investigated the impact of F-doing on CeO1-xFxBiS2 in terms of the electronic-structural parameters of Anderson's impurity-model analysis. It was recently reported using Ce L3-edge x-ray absorption spectroscopy (XAS) that CeOBiS2 falls in the Ce valence fluctuation regime and the F-doping drives the system into the Kondo regime. The Ce L3- edge XAS spectra with the various F-doping levels can be reproduced by adjusting the transfer integral in the Anderson's impurity model. The present analysis indicates that the F-doping to the system corresponds to the decrease of the Ce-Bi transfer integral.

Sugimoto, Takuya; Joseph, Boby; Paris, Eugenio; Iadecola, Antonella; Demura, Satoshi; Mizuguchi, Yoshikazu; Takano, Yoshihiko; Mizokawa, Takashi; Saini, Naurang L.

2015-03-01

410

Positron excitation of neon  

NASA Technical Reports Server (NTRS)

The differential and total cross section for the excitation of the 3s1P10 and 3p1P1 states of neon by positron impact were calculated using a distorted-wave approximation. The results agree well with experimental conclusions.

Parcell, L. A.; Mceachran, R. P.; Stauffer, A. D.

1990-01-01

411

A finite-frequency functional RG approach to the single impurity Anderson model  

Microsoft Academic Search

We use the Matsubara functional renormalization group (FRG) to describe\\u000aelectronic correlations within the single impurity Anderson model. In contrast\\u000ato standard FRG calculations, we account for the frequency-dependence of the\\u000atwo-particle vertex in order to address finite-energy properties (e.g, spectral\\u000afunctions). By comparing with data obtained from the numerical renormalization\\u000agroup (NRG) framework, the FRG approximation is shown to

C. Karrasch; R. Hedden; R. Peters; Th. Pruschke; K Schonhammer; V. Meden

2008-01-01

412

A finite-frequency functional renormalization group approach to the single impurity Anderson model  

Microsoft Academic Search

We use the Matsubara functional renormalization group (FRG) to describe electronic correlations within the single impurity Anderson model. In contrast to standard FRG calculations, we account for the frequency dependence of the two-particle vertex in order to address finite-energy properties (e.g, spectral functions). By comparing with data obtained from the numerical renormalization group (NRG) framework, the FRG approximation is shown

C. Karrasch; R. Hedden; R. Peters; Th Pruschke; K. Schönhammer; V. Meden

2008-01-01

413

Counting statistics for the Anderson impurity model: Bethe ansatz and Fermi liquid study  

Microsoft Academic Search

We study the counting statistics of charge transport in the Anderson impurity\\u000amodel (AIM) employing both Keldysh perturbation theory in a Fermi liquid\\u000apicture and the Bethe ansatz. In the Fermi liquid approach, the object of our\\u000aprincipal interest is the generating function for the cumulants of the charge\\u000acurrent distribution. We derive an exact analytic formula relating the full

A. O. Gogolin; R. M. Konik; A. W. W. Ludwig; H. Saleur

2007-01-01

414

High prevalence of subclinical hypothyroidism in patients with Anderson–Fabry disease  

Microsoft Academic Search

Summary  Anderson–Fabry disease is a rare lysosomal storage disorder. It results from a deficiency of the lysosomal ?-galactosidase\\u000a A and leads to progressive accumulation of globotriaosylceramide in the endothelium and tissue cells of various organs. Some\\u000a of the typical clinical findings such as tiredness, dry skin, myalgia and arthralgia as well as vague gastrointestinal complaints\\u000a are also symptoms of hypothyroidism. Therefore,

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

2005-01-01

415

Anderson-Hynes pyeloplasty in horseshoe kidney in children: is it effective without symphysiotomy?  

Microsoft Academic Search

Contemporary reports on surgery for horseshoe kidney (HK) still recommend isthmotomy and lateropexy to complete an open pyeloplasty.\\u000a To evaluate whether simple Anderson-Hynes pyeloplasty without symphysiotomy is effective for relief of ureteropelvic junction\\u000a obstruction (UPJO) in HK, we studied the records of ten children, two of whom had bilateral UPJO. Only one child presented\\u000a with calculi; 11 units were operated

T. Schuster; H. G. Dietz; S. Schütz

1999-01-01

416

MD Anderson study finds Black patients with kidney cancer have poorer survival than whites  

Cancer.gov

Among patients with the most common form of kidney cancer, whites consistently have a survival advantage over blacks, regardless of patient and tumor characteristics or surgical treatment. That is the conclusion of a new University of Texas MD Anderson Cancer Center study published early online in CANCER, a peer-reviewed journal of the American Cancer Society. The study's results suggest that additional efforts are needed to prolong the survival of all patients with kidney cancer.

417

MD Anderson study finds qigong improves quality of life for breast cancer patients undergoing radiation therapy  

Cancer.gov

Researchers from The University of Texas MD Anderson Cancer Center have found qigong, an ancient mind-body practice, reduces depressive symptoms and improves quality of life in women undergoing radiotherapy for breast cancer. The study, published in the journal Cancer, is the first to examine qigong in patients actively receiving radiation therapy and includes a follow-up period to assess benefits over time.

418

MD Anderson study shows new approach connecting smokers to quit lines increases smoking cessation treatment enrollment  

Cancer.gov

Self-identified smokers directly connected to a tobacco cessation quit line are 13 times more likely to enroll in a treatment program as compared to smokers who are handed a quit line referral card and encouraged to call on their own, according to a new study led by researchers at the University of Texas MD Anderson Cancer Center and published online in JAMA Internal Medicine.

419

Approximation of modified Anderson-Darling test statistics for extreme value distributions with unknown shape parameter  

NASA Astrophysics Data System (ADS)

Studies of the goodness-of-fit test, which describes how well a model fits a set of observations with an assumed distribution, have long been the subject of statistical research. The selection of an appropriate probability distribution is generally based on goodness-of-fit tests. This test is an effective means of examining how well a sample data set agrees with an assumed probability distribution that represents its population. However, the empirical distribution function test gives equal weight to the differences between the empirical and theoretical distribution functions corresponding to all observations. The modified Anderson-Darling test, suggested by Ahmad et al. (1988), uses a weight function that emphasizes the tail deviations at the upper or lower tails. In this study, we derive new regression equation forms of the critical values for the modified Anderson-Darling test statistics considering the effect of unknown shape parameters. The regression equations are derived using simulation experiments for extreme value distributions such as the log-Gumbel, generalized Pareto, GEV, and generalized logistic models. In addition, power test and at-site frequency analyses are performed to evaluate the performance and to explain the applicability of the modified Anderson-Darling test.

Heo, Jun-Haeng; Shin, Hongjoon; Nam, Woosung; Om, Juseong; Jeong, Changsam

2013-08-01

420

Charge transfer excitations from excited state Hartree-Fock subsequent minimization scheme  

SciTech Connect

Photoinduced charge-transfer processes play a key role for novel photovoltaic phenomena and devices. Thus, the development of ab initio methods that allow for an accurate and computationally inexpensive treatment of charge-transfer excitations is a topic that nowadays attracts a lot of scientific attention. In this paper we extend an approach recently introduced for the description of single and double excitations [M. Tassi, I. Theophilou, and S. Thanos, Int. J. Quantum Chem. 113, 690 (2013); M. Tassi, I. Theophilou, and S. Thanos, J. Chem. Phys. 138, 124107 (2013)] to allow for the description of intermolecular charge-transfer excitations. We describe an excitation where an electron is transferred from a donor system to an acceptor one, keeping the excited state orthogonal to the ground state and avoiding variational collapse. These conditions are achieved by decomposing the space spanned by the Hartree-Fock (HF) ground state orbitals into four subspaces: The subspace spanned by the occupied orbitals that are localized in the region of the donor molecule, the corresponding for the acceptor ones and two more subspaces containing the virtual orbitals that are localized in the neighborhood of the donor and the acceptor, respectively. Next, we create a Slater determinant with a hole in the subspace of occupied orbitals of the donor and a particle in the virtual subspace of the acceptor. Subsequently we optimize both the hole and the particle by minimizing the HF energy functional in the corresponding subspaces. Finally, we test our approach by calculating the lowest charge-transfer excitation energies for a set of tetracyanoethylene-hydrocarbon complexes that have been used earlier as a test set for such kind of excitations.

Theophilou, Iris, E-mail: i.theophilou@fz-juelich.de [Peter Grunberg Institut (PGI) Forschungszentrum Jülich, D-52425 Jülich (Germany)] [Peter Grunberg Institut (PGI) Forschungszentrum Jülich, D-52425 Jülich (Germany); Tassi, M.; Thanos, S. [Institute for Advanced Materials, Physicochemical Processes, Nanotechnology and Microsystems, ‘Demokritos’ National Center for Scientific Research, 15310 Athens (Greece)] [Institute for Advanced Materials, Physicochemical Processes, Nanotechnology and Microsystems, ‘Demokritos’ National Center for Scientific Research, 15310 Athens (Greece)

2014-04-28

421

Charge transfer excitations from excited state Hartree-Fock subsequent minimization scheme.  

PubMed

Photoinduced charge-transfer processes play a key role for novel photovoltaic phenomena and devices. Thus, the development of ab initio methods that allow for an accurate and computationally inexpensive treatment of charge-transfer excitations is a topic that nowadays attracts a lot of scientific attention. In this paper we extend an approach recently introduced for the description of single and double excitations [M. Tassi, I. Theophilou, and S. Thanos, Int. J. Quantum Chem. 113, 690 (2013); M. Tassi, I. Theophilou, and S. Thanos, J. Chem. Phys. 138, 124107 (2013)] to allow for the description of intermolecular charge-transfer excitations. We describe an excitation where an electron is transferred from a donor system to an acceptor one, keeping the excited state orthogonal to the ground state and avoiding variational collapse. These conditions are achieved by decomposing the space spanned by the Hartree-Fock (HF) ground state orbitals into four subspaces: The subspace spanned by the occupied orbitals that are localized in the region of the donor molecule, the corresponding for the acceptor ones and two more subspaces containing the virtual orbitals that are localized in the neighborhood of the donor and the acceptor, respectively. Next, we create a Slater determinant with a hole in the subspace of occupied orbitals of the donor and a particle in the virtual subspace of the acceptor. Subsequently we optimize both the hole and the particle by minimizing the HF energy functional in the corresponding subspaces. Finally, we test our approach by calculating the lowest charge-transfer excitation energies for a set of tetracyanoethylene-hydrocarbon complexes that have been used earlier as a test set for such kind of excitations. PMID:24784248

Theophilou, Iris; Tassi, M; Thanos, S

2014-04-28

422

Charge transfer from delocalized excited states in a bulk heterojunction material  

NASA Astrophysics Data System (ADS)

Charge generation in an organic photovoltaic blend was investigated using transient absorption spectroscopy. In films of pure electron donating material, subpicosecond spectral oscillations were observed and assigned to torsional modes associated with excited state relaxation and localization. These modes are systematically suppressed in the presence of fullerene, indicating that a significant fraction of charge transfer occurs prior to excited state localization.

Kaake, Loren G.; Moses, Daniel; Heeger, Alan J.

2015-02-01

423

Localization on the Landscape and Eternal Inflation  

E-print Network

We investigate the validity of the assertion that eternal inflation populates the landscape of string theory. We verify that bubble solutions do not satisfy the Klein Gordon equation for the landscape potential. Solutions to the landscape potential within the formalism of quantum cosmology are Anderson localized wavefunctions. Those are inconsistent with inflating bubble solutions. The physical reasons behind the failure of a relation between eternal inflation and the landscape are rooted in quantum phenomena such as interference between wavefunction concentrated around the various vacua in the landscape.

Laura Mersini-Houghton; Malcolm J. Perry

2014-04-22

424

Magnetostrictive resonance excitation  

DOEpatents

The resonance frequency spectrum of a magnetostrictive sample is remotely determined by exciting the magnetostrictive property with an oscillating magnetic field. The permeability of a magnetostrictive material and concomitant coupling with a detection coil varies with the strain in the material whereby resonance responses of the sample can be readily detected. A suitable sample may be a magnetostrictive material or some other material having at least one side coated with a magnetostrictive material. When the sample is a suitable shape, i.e., a cube, rectangular parallelepiped, solid sphere or spherical shell, the elastic moduli or the material can be analytically determined from the measured resonance frequency spectrum. No mechanical transducers are required and the sample excitation is obtained without contact with the sample, leading to highly reproducible results and a measurement capability over a wide temperature range, e.g. from liquid nitrogen temperature to the Curie temperature of the magnetostrictive material.

Schwarz, Ricardo B. (Los Alamos, NM); Kuokkala, Veli-Tapani (Tampere, FI)

1992-01-01

425

Apparatus for photon excited catalysis  

NASA Technical Reports Server (NTRS)

An apparatus is described for increasing the yield of photonically excited gas phase reactions by extracting excess energy from unstable, excited species by contacting the species with the surface of a finely divided solid.

Saffren, M. M. (inventor)

1977-01-01

426

Harmonically excited orbital variations  

SciTech Connect

Rephrasing the equations of motion for orbital maneuvers in terms of Lagrangian generalized coordinates instead of Newtonian rectangular cartesian coordinates can make certain harmonic terms in the orbital angular momentum vector more readily apparent. In this formulation the equations of motion adopt the form of a damped harmonic oscillator when torques are applied to the orbit in a variationally prescribed manner. The frequencies of the oscillator equation are in some ways unexpected but can nonetheless be exploited through resonant forcing functions to achieve large secular variations in the orbital elements. Two cases are discussed using a circular orbit as the control case: (1) large changes in orbital inclination achieved by harmonic excitation rather than one impulsive velocity change, and (2) periodic and secular changes to the longitude of the ascending node using both stable and unstable excitation strategies. The implications of these equations are also discussed for both artificial satellites and natural satellites. For the former, two utilitarian orbits are suggested, each exploiting a form of harmonic excitation. 5 refs.

Morgan, T.

1985-08-06

427

Aperture excited dielectric antennas  

NASA Technical Reports Server (NTRS)

The results of a comprehensive experimental and theoretical study of the effect of placing dielectric objects over the aperture of waveguide antennas are presented. Experimental measurements of the radiation patterns, gain, impedance, near-field amplitude, and pattern and impedance coupling between pairs of antennas are given for various Plexiglas shapes, including the sphere and the cube, excited by rectangular, circular, and square waveguide feed apertures. The waveguide excitation of a dielectric sphere is modeled using the Huygens' source, and expressions for the resulting electric fields, directivity, and efficiency are derived. Calculations using this model show good overall agreement with experimental patterns and directivity measurements. The waveguide under an infinite dielectric slab is used as an impedance model. Calculations using this model agree qualitatively with the measured impedance data. It is concluded that dielectric loaded antennas such as the waveguide excited sphere, cube, or sphere-cylinder can produce directivities in excess of that obtained by a uniformly illuminated aperture of the same cross section, particularly for dielectric objects with dimensions of 2 wavelengths or less. It is also shown that for certain configurations coupling between two antennas of this type is less than that for the same antennas without dielectric loading.

Crosswell, W. F.; Chatterjee, J. S.; Mason, V. B.; Tai, C. T.

1974-01-01

428

Generation of finite wave trains in excitable media.  

PubMed

Spatiotemporal control of excitable media is of paramount importance in the development of new applications, ranging from biology to physics. To this end, we identify and describe a qualitative property of excitable media that enables us to generate a sequence of traveling pulses of any desired length, using a one-time initial stimulus. The wave trains are produced by a transient pacemaker generated by a one-time suitably tailored spatially localized finite amplitude stimulus, and belong to a family of fast pulse trains. A second family, of slow pulse trains, is also present. The latter are created through a clumping instability of a traveling wave state (in an excitable regime) and are inaccessible to single localized stimuli of the type we use. The results indicate that the presence of a large multiplicity of stable, accessible, multi-pulse states is a general property of simple models of excitable media. PMID:21572974

Yochelis, A; Knobloch, E; Xie, Y; Qu, Z; Garfinkel, A

2008-09-12

429

Generation of finite wave trains in excitable media  

PubMed Central

Spatiotemporal control of excitable media is of paramount importance in the development of new applications, ranging from biology to physics. To this end, we identify and describe a qualitative property of excitable media that enables us to generate a sequence of traveling pulses of any desired length, using a one-time initial stimulus. The wave trains are produced by a transient pacemaker generated by a one-time suitably tailored spatially localized finite amplitude stimulus, and belong to a family of fast pulse trains. A second family, of slow pulse trains, is also present. The latter are created through a clumping instability of a traveling wave state (in an excitable regime) and are inaccessible to single localized stimuli of the type we use. The results indicate that the presence of a large multiplicity of stable, accessible, multi-pulse states is a general property of simple models of excitable media. PMID:21572974

Yochelis, A.; Knobloch, E.; Xie, Y.; Qu, Z.; Garfinkel, A.

2011-01-01

430

Double Excitations of Helium  

NASA Astrophysics Data System (ADS)

The double excitations of helium offer an ideal case for investigating electron dynamics in a three-body system. Our study of the He ^1P^o double excitations comprises measurements of the partial photoionization cross sections ?n (He^+) and the partial photoelectron angular distribution parameters ?n for the series N(K,T)^Ai up to the N=5 threshold. The experiment was performed at the ALS undulator beam line 9.0.1., which provided a photon flux of 2 × 10^12 photons per second with a small photon energy bandpass of 7 to 12 meV. This level of differentiation, along with the small bandpass, offers the most critical assessment of the dynamics of the two-electron excitations to date. The principal series K=N-2 are clearly delineated in both ?n and ?_n. The ?n show all minor series with N=K-4 very clearly, in contrast to measurements of the total absorption cross section, as well as very weak members with A=-1. Excellent accord between experiment and theory, particularly the hyperspherical close-coupling method, was found for the dynamic properties in all instances, including the interference pattern due to an overlap of N=5 and N=6 series members. Generally, the Rydberg series of resonance-induced profiles vary greatly depending on the final ionic state He^+(n), whereas the peak-to-valley variation in the ?n within a given series N is of similar magnitude for all n. Interestingly, a striking systematic trend is noted through the various series: the resonance-induced profiles for both the ?n and ?n of the photoelectron satellites are virtually identical provided the final ionic state He^+(n), n >= 2, is reached via an excited series N with ?=1, or ?=2, where ?=N-n. This overall pattern might be attributed to the general similarity of states with the same set of approximately good quantum numbers (N-K), A, and T. We tentatively propose an extension of these systematics for higher series N >= 5, although further theoretical work toward understanding these features of the doubly excited states will be needed. The experiment was performed in close collaboration with C.D. Caldwell, M.O. Krause, S.P. Frigo, and S.B. Whitfield. Valuable theoretical contributions were made by J.-Z. Tang and I. Shimamura. Part of the work appeared in Phys. Rev. Lett. 75, 1479 (1995). This work is supported by the National Science Foundation under grants PHY-9207634 and PHY-9507573.

Menzel, Alexander

1996-05-01

431

Seasonal excitation of polar motion  

NASA Astrophysics Data System (ADS)

We estimate geophysical excitations (?1 and ?2) of polar motion using multiple sources of data, including recent atmospheric, oceanic, and hydrological models, satellite gravity measurements from the Gravity Recovery and Climate Experiment (GRACE), and compare geophysical excitations with observed polar motion excitations from space geodetic techniques. At seasonal time scales, both model-estimated excitations from the geophysical fluids envelope (i.e., atmosphere, ocean, and hydrosphere) and GRACE-observed excitations agree remarkably well with polar motion observations in the ?2 component, and in the ?1 component, model estimates and observed geodetic excitations show significant discrepancies. However, mass excitations estimated from GRACE show significantly better agreement with observed excitations than those from models, especially in ?1, due to better quantification of terrestrial water storage and oceanic mass changes using GRACE data. Furthermore, GRACE satellite gravity measurements offer a unique means for quantifying contributions from cryospheric angular momentum (CAM) change, a component mostly neglected in previous studies due to the lack of adequate observations or reliable ice sheets models. Based on GRACE estimates, CAM excitations appear a minor, but not negligible contributor to seasonal excitations of polar motion. The significantly better agreement in ?2 (than that in ?1) between observations and model excitations is related to the higher sensitivity of ?2 excitations to atmospheric pressure and terrestrial water changes over the Eurasia and North American continents, because of the special relationship between the ?S21 spherical harmonic coefficient (proportional to ?2) mass model and the locations of the two continents.

Chen, J. L.; Wilson, C. R.; Zhou, Y. H.

2012-12-01

432

Excitation of resonances of microspheres on an optical fiber  

Microsoft Academic Search

Morphology-dependent resonances (MDR's) of solid microspheres are excited by using an optical fiber coupler. The narrowest measured MDR linewidths are limited by the excitation laser linewidth (,0.025 nm). Only MDR's, with an on-resonance to off-resonance intensity ratio of 104, contribute to scattering. The intensity of various resonance orders is understood by the localization principle and the recently developed generalized Lorentz

A. Serpengüzel; S. Arnold; G. Griffel

1995-01-01

433

Get excited: reappraising pre-performance anxiety as excitement.  

PubMed

Individuals often feel anxious in anticipation of tasks such as speaking in public or meeting with a boss. I find that an overwhelming majority of people believe trying to calm down is the best way to cope with pre-performance anxiety. However, across several studies involving karaoke singing, public speaking, and math performance, I investigate an alternative strategy: reappraising anxiety as excitement. Compared with those who attempt to calm down, individuals who reappraise their anxious arousal as excitement feel more excited and perform better. Individuals can reappraise anxiety as excitement using minimal strategies such as self-talk (e.g., saying "I am excited" out loud) or simple messages (e.g., "get excited"), which lead them to feel more excited, adopt an opportunity mind-set (as opposed to a threat mind-set), and improve their subsequent performance. These findings suggest the importance of arousal congruency during the emotional reappraisal process. PMID:24364682

Brooks, Alison Wood

2014-06-01

434

Excitation of Resonant Helioseimic Modes by Solar Flares  

NASA Astrophysics Data System (ADS)

Flares are known to excite propagating sound waves in the solar atmosphere, and Maurya et al. (2009), using a local analysis (ring diagrams) of the 2003 Halloween flare, showed that they excite resonant p-modes as well. We confirm and extend here these results by: applying the same analysis to other locations on the Sun at the time of the Halloween flare, analyzing other events also showing a signature of p-mode excitation, looking in detail at the results of the ring diagrams analysis in terms of noise fitting and the center-to-limb variation of ring-diagram power.

Leibacher, John William; Baudin, Frédéric; Rabello Soares, Maria Cristina

2015-04-01

435

Optical study of orbital excitations in transition-metal oxides  

Microsoft Academic Search

The orbital excitations of a series of transition-metal compounds are studied by means of optical spectroscopy. Our aim was to identify signatures of collective orbital excitations by comparison with experimental and theoretical results for predominantly local crystal-field excitations. To this end, we have studied TiOCl, RTiO3 (R = La, Sm and Y), LaMnO3, Y2BaNiO5, CaCu2O3 and K4Cu4OCl10, ranging from early

R. Rückamp; E. Benckiser; M. W. Haverkort; H. Roth; T. Lorenz; A. Freimuth; L. Jongen; A. Möller; G. Meyer; P. Reutler; B. Büchner; A. Revcolevschi; S.-W. Cheong; C. Sekar; G. Krabbes; M. Grüninger

2005-01-01

436

Localization for a Nonlinear Sigma Model in a Strip Related to Vertex Reinforced Jump Processes  

NASA Astrophysics Data System (ADS)

We study a lattice sigma model which is expected to reflect Anderson localization and delocalization transition for real symmetric band matrices in 3D, but describes the mixing measure for a vertex reinforced jump process too. For this model we prove exponential localization at any temperature in a strip, and more generally in any quasi-one dimensional graph, with pinning (mass) at only one site. The proof uses a Mermin-Wagner type argument and a transfer operator approach.

Disertori, Margherita; Merkl, Franz; Rolles, Silke W. W.

2014-12-01

437

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

USGS Publications Warehouse

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. During August–October 1999, several field trips were conducted in the vicinity of Anderson Springs to continue monitoring and sampling the thermal manifestations. The new fumarolic area had increased in temperature and in discharge intensity since 1998, and a zone of dead trees had developed on the steep bank directly west of the fumaroles. Ground temperatures and diffuse flow of CO2 flow through soils were measured in the area surrounding the main spring and new fumaroles and in the zone of tree-kill.

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

438

Excited States and Photons  

NSDL National Science Digital Library

Investigate how atoms can be excited to give off radiation (photons) with models of electron energy diagrams. Explore the effects of energy levels in atoms through interactive computer models. Learn about the different electron orbitals of an atom, and explore three-dimensional models of the atoms. Learn about photons and why they are emitted, and gain an understanding of the link between energy levels and photons as you discover how an atom?s electron configuration affects which wavelengths of light it will admit or absorb.

The Concord Consortium

2011-12-13

439

Dipole Excitation of Dipositronium  

E-print Network

The energy interval between the ground and the P-wave excited states of the recently discovered positronium molecule Ps_2 is evaluated, including the relativistic and the leading logarithmic radiative corrections, E_P-E_S = 0.181 586 7(8) a.u. The P-state, decaying usually via annihilation, is found to decay into the ground state by an electric dipole transition 19 percent of the time. Anticipated observation of this transition will provide insight into this exotic system.

Mariusz Puchalski; Andrzej Czarnecki

2008-09-30

440

Local magnitude scale in Slovenia  

NASA Astrophysics Data System (ADS)

The Seismology and Geology Office of the Environmental Agency of the Republic of Slovenia is recording and processing data about the earthquakes occurring in Slovenia and the surrounding areas. For the last 30 years the magnitudes MLV of the earthquakes recorded by the Slovenian seismic stations were computed using the maximum ground velocity on the vertical component with the attenuation determined to fit the magnitudes recorded by Wood-Anderson seismograph in Trieste. In the last 15 years the digital seismic network of the Republic of Slovenia has grown from 6 to 28 permanent seismic stations and recorded large set of earthquakes, but attenuation relation for the local magnitude has not been re-evaluated yet. We use a large data set of earthquakes occurring in the area between 44.6° and 47.0° N and 12.0° and 17.0° E in the period from January 1997 to December 2010 to calibrate the local magnitude equations. An iterative least-square method is used to determine distance attenuation coefficients and station corrections for the Wood-Anderson magnitude (MWA). The magnitude equation is obtained from the automatically determined amplitudes from simulated Wood-Anderson seismograms of more than 1800 earthquakes. The magnitude span of the data used is between M = 0.6 and M = 5.2, with all but few tens of events between M = 1 and M = 3 and the hypocentral distance span from 20 km to 280 km, with less than 0.4 % of the distances larger than 210 km. The relation obtained is ( ) j r[km]- M WA = log (A [mm ])+ 1.38log 100 km + 3.0+ Cj , where A is the maximum amplitude on the horizontal component of the synthetic Wood-Anderson seismogram, r is the hypocentral distance and index j refers to the station, so that Cj is the station correction. Station corrections Cj obtained for 30 stations are in the range from -0.26 to 0.30. Currently, the MLV of an event is determined as the mean of the MLV magnitudes at individual stations, using a single magnitude equation with no station correction terms. The same set of recordings is used to determine the coefficients in the relation for MLV . For the calibration of the MLV magnitude equation the data of more than 3100 earthquakes is used. Attenuation in the calibrated MLV equation is somewhat higher than the one used presently by the Seismology and Geology Office. However, the MLV values obtained using the present single equation and the new equation with station corrections do not differ significantly. The main gain of the introduction of the station corrections is the reduction of the MLV uncertainty by about 35 %. By comparing MLV and MWA as obtained in the first part of the study, we show that the linear function MWA = 1.06MLV - 0.075 describes well the relation between the two magnitudes. However, it has limited use, since the magnitude span of the data used is mostly between M = 1 and M = 3, with just a few tens of events with M > 3. Nevertheless, the difference between the two local magnitudes does not exceed 0.3 for most of the events with both magnitudes determined.

Bajc, J.; Zaplotnik, Ž.; Živ?i?, M.; ?arman, M.

2012-04-01

441

Electron excitation of a Jovian Aurora  

NASA Technical Reports Server (NTRS)

Because Jupiter possesses a magnetic field, auroral activity is very likely. The auroral emissions due to electron precipitation are estimated for a model atmosphere with and without helium. The incident primary electrons, which are characterized by representative spectra, are degraded in energy by applying the continuous slow down approximation. All secondaries, tertiaries, and higher generation electrons are assumed to be absorbed locally. A compilation of excitation, dissociation, and ionization cross section data for H, H2, and He are used to model all aspects of the energy deposition process. Volume emission rates are calculated from the total direct excitation rates, and appropriate corrections for cascading are applied. Helium emissions are relatively small because the majority of electrons are absorbed above the region of maximum He concentration.

Heaps, M. G.; Bass, J. N.; Green, A. E. S.

1973-01-01

442

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

PubMed

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." PMID:25423683

O'Connell, William D

2014-11-01

443

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

PubMed

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." PMID:25507406

O'Connell, William D

2014-11-01

444

STS-89 Mission Specialist Michael Anderson is assisted with his flight suit in the white room  

NASA Technical Reports Server (NTRS)

STS-89 Mission Specialist Michael Anderson is assisted with his ascent and re-entry flight suit in the white room at Launch Pad 39A before entering Space Shuttle Endeavour for launch. The STS- 89 mission will be the eighth docking of the Space Shuttle with the Russian Space Station Mir. After docking, Mission Specialist Andrew Thomas, Ph.D., will transfer to the space station, succeeding David Wolf, M.D., who will return to Earth aboard Endeavour. Dr. Thomas will live and work on Mir until June. STS- 89 is scheduled for a Jan. 22 liftoff at 9:48 p.m.

1998-01-01

445

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

NASA Technical Reports Server (NTRS)

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.

2007-01-01

446

STS-107 Payload Commander Michael Anderson during TCDT M113 training activities  

NASA Technical Reports Server (NTRS)

KENNEDY SPACE CENTER, FLA. -- -- STS-107 Payload Commander Michael Anderson takes a break during training on the operation of an M113 armored personnel carrier during Terminal Countdown Demonstration Test activities, a standard part of launch preparations. 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.

2002-01-01

447

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

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

448

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

SciTech Connect

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.

Metzger, I.; Van Geet, O.

2014-06-01

449

MD Anderson study finds metabolic protein launches sugar feast that nurtures brain tumors  

Cancer.gov

Researchers at The University of Texas MD Anderson Cancer Center have tracked down a cancer-promoting protein's pathway into the cell nucleus and discovered how, once there, it fires up a glucose metabolism pathway on which brain tumors thrive. They also found a vital spot along the protein's journey that can be attacked with a type of drug not yet deployed against glioblastoma multiforme, the most common and lethal form of brain cancer. Published online by Nature Cell Biology, the paper further illuminates the importance of pyruvate kinase M2 (PKM2) in cancer development and progression.

450

Atmospheric optical turbulence measurements taken at Anderson Mesa, Flagstaff, Arizona between 13-19 November 1989  

NASA Astrophysics Data System (ADS)

From 13 to 19 November 1989, the Naval Postgraduate School Atmospheric Optics Group acquired atmospheric optical turbulence measurements at the 31-inch Lowell Observatory telescope dome facility on Anderson Mesa, 16 km southeast of Flagstaff, Arizona. The parameters measured, the transverse coherence length and the isoplanatic angle, were part of an ongoing site survey for a large-scale, ground-based, synthetic aperture system (100 to 300 m baseline stellar interferometer). This report compiles, analyses and summarizes the acquired optical data. Also discussed are the synoptic meteorological events present during the data acquisition period.

Vaucher, Gail T.; Vaucher, Christopher A.; Walters, Donald L.

1991-01-01

451

Anisotropic behavior of quantum transport in graphene superlattices: Coexistence of ballistic conduction with Anderson insulating regime  

NASA Astrophysics Data System (ADS)

We report on the possibility to generate highly anisotropic quantum conductivity in disordered graphene-based superlattices. Our quantum simulations, based on an efficient real-space implementation of the Kubo-Greenwood formula, show that in disordered graphene superlattices the strength of multiple scattering phenomena can strongly depend on the transport measurement geometry. This eventually yields the coexistence of a ballistic waveguide and a highly resistive channel (Anderson insulator) in the same two-dimensional platform, evidenced by a ?yy/?xx ratio varying over several orders of magnitude, and suggesting the possibility of building graphene electronic circuits based on the unique properties of chiral massless Dirac fermions in graphene.

Pedersen, Jesper Goor; Cummings, Aron W.; Roche, Stephan

2014-04-01

452

MD Anderson study finds blood vessel cells coax colorectal cancer cells into more dangerous state  

Cancer.gov

Blood vessels that supply oxygen and nutrients to tumors can also deliver something else -- a signal that strengthens nearby cancer cells, making them more resistant to chemotherapy, more likely to spread to other organs and more lethal, scientists at The University of Texas MD Anderson Cancer Center report online in Cancer Cell. Working in human colorectal cancer cell lines and tumor samples, as well as mouse models, the researchers found that endothelial cells, which line the inside of blood vessels, can trigger changes in cancer cells without even coming into direct contact with them.

453

MD Anderson study finds depression and shortened telomeres increase bladder cancer mortality  

Cancer.gov

The combination of shortened telomeres, a biological marker of aging associated with cancer development, and elevated depression significantly impacted bladder cancer mortality, according to data presented at the 11th Annual AACR International Conference on Frontiers in Cancer Prevention Research. As part of an ongoing, large-scale epidemiologic study of bladder cancer, researchers from the MD Anderson Cancer Center in Houston collected clinical and mental health information on 464 patients with bladder cancer. They assessed patients' depression levels with the Center for Epidemiologic Studies Depression Scale.

454

Observation of the Anderson Metal-Insulator Transition with Atomic Matter Waves: Theory and Experiment  

E-print Network

Using a cold atomic gas exposed to laser pulses -- a realization of the chaotic quasiperiodic kicked rotor with three incommensurate frequencies -- we study experimentally and theoretically the Anderson metal-insulator transition in three dimensions. Sensitive measurements of the atomic wavefunction and the use of finite-size scaling techniques make it possible to unambiguously demonstrate the existence of a quantum phase transition and to measure its critical exponents. By taking proper account of systematic corrections to one-parameter scaling, we show the universality of the critical exponent $\

Gabriel Lemarié; Julien Chabé; Pascal Szriftgiser; Jean-Claude Garreau; Benoît Grémaud; Dominique Delande

2009-07-20

455

MD Anderson study finds link between statins and improved survival in inflammatory breast cancer  

Cancer.gov

Researchers from The University of Texas MD Anderson Cancer Center found statins, the commonly used drug to lower cholesterol, improved progression-free survival in patients with inflammatory breast cancer (IBC). The retrospective study was presented in a poster discussion at the 2012 CTRC-AACR San Antonio Breast Cancer Symposium and follows a previously reported Danish study indicating there is some evidence to suggest the anti-inflammatory properties of statins could reduce the risk of breast cancer recurrence. Still, the overall effects of statins have not been examined in relation to IBC.

456

Portuguese validation of the Symptom Inventory of the M.D. Anderson Cancer Center.  

PubMed

Objective 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. Method A cross-sectional study with 268 cancer patients in outpatient treatment, in the municipality of Ijuí, state of Rio Grande do Sul, Brazil. Results 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%). Conclusion The Brazilian version of the MD Anderson Symptom Inventory - core showed adequate psychometric properties in the studied population.Objetivo Analisar a confiabilidade e a validade das propriedades psicométricas da versão brasileira do instrumento de avaliação de sintomas, intitulado Inventário de Sintomas do M.D. Anderson - core. Método Estudo transversal do qual participaram 268 pacientes com câncer em tratamento ambulatorial, do Município de Ijuí, Rio Grande do Sul, Brasil. Resultados O Alfa de Cronbach MDASI geral, os sintomas e as interferências foram respectivamente (0,857), (0,784) e (0,794). A análise fatorial demonstrou adequação dos dados (0,792). Identificaram-se quatro fatores dos principais componentes relacionados aos sintomas. Fator I: problemas de sono, preocupações, dificuldades de lembrar-se das coisas e tristeza. Fator II: enjoo, náuseas, falta de apetite e vômito. Fator III: sonolência, boca seca, dormência e formigamento. Fator IV: dor, fadiga e falta de ar. Evidenciou-se um único fator no componente interferências na vida (0,780), prevalecendo para atividade em geral (59,7%), trabalho (54,9%) e para caminhar (49,3%). Conclusão A versão brasileira do Inventário de M.D. Anderson-core mostrou propriedades psicométricas adequadas na população avaliada. PMID:25626498

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

2014-12-01

457

Variational Monte Carlo study of magnetic states in the periodic Anderson model  

NASA Astrophysics Data System (ADS)

We study the magnetic states of the periodic Anderson model with a finite Coulomb interaction between f electrons on a square lattice by applying variational Monte Carlo method. We consider Gutzwiller wavefunctions for the paramagnetic, antiferromagnetic, ferromagnetic, and charge density wave states. We find an antiferromagnetic phase around half-filling. There is a phase transition accompanying change in the Fermi-surface topology in this antiferromagnetic phase. We also study a case away from half-filling, and find a ferromagnetic state as the ground state there.

Kubo, Katsunori

2015-03-01

458

Excitation energies of molecules within time-independent density functional theory  

SciTech Connect

Recently proposed exchange energy functional for excited-states is tested for obtaining excitation energies of diatomic molecules. The functional is the ground-state counterpart of the local-density approximation, the modified local spin density (MLSD). The MLSD functional is tested for the N{sub 2} and CO diatomic molecules. The excitation energy obtained with the MLSD functional for the N{sub 2} molecule is in close vicinity to that obtained from the exact exchange orbital functional, Krieger, Li and Iafrate (KLI). For the CO molecule, the departure in excitation energy is observed and is due to the overcorrection of self-interaction.

Hemanadhan, M., E-mail: hemanadh@iitk.ac.in; Harbola, Manoj K., E-mail: hemanadh@iitk.ac.in [Department of Physics, Indian Institute of Technology Kanpur, Kanpur-208016 (India)

2014-04-24

459

Electronic excitation as a mode of heat dissipation in laser-driven cluster plasmas  

SciTech Connect

Electrons streaming out of laser plasma are known for non-local heat transport and energy deposition by the ionization wave. At 100 eV electron temperature, since the electronic excitation cross section is comparable to that of ionization for Ar and CO{sub 2}, a non-local excitation wave akin to the ionization wave is envisaged where energy deposition in excitations forms a excited cluster sheath beyond the laser focus. Here, we show that nano-cluster systems have the right parameters to form such an exciton sheath and experimentally demonstrate this via charge transfer reactions.

Rajeev, R.; Rishad, K. P. M.; Madhu Trivikram, T.; Krishnamurthy, M. [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai-5 (India)] [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai-5 (India)

2013-12-15

460

On the possibility of explaining the high rate of flux creep at ultra-low temperatures using the Anderson model  

NASA Astrophysics Data System (ADS)

The nonvanishing magnetic relaxation rate and noticeable resistance in the resistive measurements in high-temperature superconductors (HTSCs) at ultra-low temperatures, which have recently been discussed as evidence of the quantum tunneling of vortices, is argued to be caused by electromagnetic noise in the framework of the modified Anderson theory. This explains the main features of this phenomenon, which cannot be described by quantum tunneling theory. Thus, the modified Anderson theory, which incorporates flux flow, the distribution of activation energies, the mutual interaction of the vortices, and the spatial variation of the pinning energy into the conventional Anderson theory, provides an explanation of the main features of magnetic flux creep in HTSCs.

Lykov, A. N.

2013-05-01

461

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

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…

Horning, Kathleen

2006-01-01

462

ANDERSON-TEIXEIRA FINAL PROOF.DOCX (DO NOT DELETE) 3/7/2011 9:29 AM DO BIOFUELS LIFE CYCLE  

E-print Network

ANDERSON-TEIXEIRA FINAL PROOF.DOCX (DO NOT DELETE) 3/7/2011 9:29 AM 589 DO BIOFUELS LIFE CYCLE ANALYSES ACCURATELY QUANTIFY THE CLIMATE IMPACTS OF BIOFUELS-RELATED LAND USE CHANGE? Kristina J. Anderson in determining the sustainability of biofuels. To ensure that legal standards are effective in limiting climate

DeLucia, Evan H.

463

Parity-dependent localization in N strongly coupled chains  

NASA Astrophysics Data System (ADS)

Anderson localization of wave functions at zero energy in quasi-one-dimensional (1D) systems of N disordered chains with interchain coupling t is examined. Localization becomes weaker than for the 1D disordered chain (t =0) when t is smaller than the longitudinal hopping t'=1, and localization becomes usually much stronger when t ?t'. This is not so for all N. We find "immunity" to strong localization for open (periodic) lateral boundary conditions when N is odd (a multiple of 4), with localization that is weaker than for t =0 and rather insensitive to t when t ?t'. The peculiar N dependence and a critical scaling with N are explained by a perturbative treatment in t'/t, and the correspondence to a weakly disordered effective chain is shown. Our results could be relevant for experimental studies of localization in photonic waveguide arrays.

Weinmann, Dietmar; Evangelou, S. N.

2014-10-01

464

Axonal excitability revisited.  

PubMed

The original papers of Hodgkin and Huxley (J. Physiol. 116 (1952a) 449, J. Physiol. 116 (1952b) 473, J. Physiol. 116 (1952c) 497, J. Physiol. 117 (1952d) 500) have provided a benchmark in our understanding of cellular excitability. Not surprisingly, their model of the membrane action potential (AP) requires revisions even for the squid giant axon, the preparation for which it was originally formulated. The mechanisms they proposed for the voltage-gated potassium and sodium ion currents, IK, and INa, respectively, have been superceded by more recent formulations that more accurately describe voltage-clamp measurements of these components. Moreover, the current-voltage relation for IK has a non-linear dependence upon driving force that is well described by the Goldman-Hodgkin-Katz (GHK) relation, rather than the linear dependence on driving force found by Hodgkin and Huxley. Furthermore, accumulation of potassium ions in the extracellular space adjacent to the axolemma appears to be significant even during a single AP. This paper describes the influence of these various modifications in their model on the mathematically reconstructed AP. The GHK and K+ accumulation results alter the shape of the AP, whereas the modifications in IK and INa gating have surprisingly little effect. Perhaps the most significant change in their model concerns the amplitude of INa, which they appear to have overestimated by a factor of two. This modification together with the GHK and the K+ accumulation results largely remove the discrepancies between membrane excitability of the squid giant axon and the Hodgkin and Huxley (J. Physiol. 117 (1952d) 500) model previously described (Clay, J. Neurophysiol. 80 (1998) 903). PMID:15561301

Clay, John R

2005-05-01

465

Multiphoton excitation of fluorescent probes.  

PubMed

This introduction reviews the multiphoton excitation cross sections of extrinsic and intrinsic fluorophores, genetically engineered probes, and nanoparticles. We will review the known two-photon excitation cross sections of biological indicators and will discuss several related issues such as how to theoretically estimate and experimentally gauge the two-photon cross section of an indicator. We provide practical guides for experimentally estimating the excitation cross section. PMID:25734074

Xu, Chris; Zipfel, Warren R

2015-01-01

466

Neuromorphic excitable maps for visual processing.  

PubMed

An excitable membrane is described which can perform different visual tasks such as contour detection, contour propagation, image segmentation, and motion detection. The membrane is designed to fit into a neuromorphic multichip system. It consists of a single two-dimensional (2-D) layer of locally connected integrate-and-fire neurons and propagates input in the subthreshold and the above-threshold range. It requires adjustment of only one parameter to switch between the visual tasks. The performance of two spiking membranes of different connectivity is compared, a hexagonally and an octagonally connected membrane. Their hardware and system suitability is discussed. PMID:17385636

Rasche, Christoph

2007-03-01

467

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

PubMed

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. PMID:23610230

Stokes, Gordon S

2013-02-01

468

Synthesis and characterization of B-type Anderson polyoxoanions supported copper complexes with mixed ligands  

NASA Astrophysics Data System (ADS)

Two novel compounds constructed by Anderson-type polyoxoanions and copper complexes with mixed ligands, (H 3O +)[Cu(C 6NO 2H 4)(phen)(H 2O)] 2[Al(OH) 6Mo 6O 18]·5H 2O (1) and (H 3O +)[Cu (C 6NO 2H 4)(phen)(H 2O)] 2[Cr(OH) 6Mo 6O 18]·5H 2O (2) have been isolated by conventional solution method, and characterized by elemental analyses, IR spectra, thermal stability analyses, X-ray powder diffraction and single-crystal X-ray diffraction. Compounds 1 and 2 are isomorphic and reveal an example of three-dimensional supramolecular organic-inorganic hybrids based on copper complexes with mixed 1,10-phenanthroline and pyridine-4-carboxylic acid ligands supported on Anderson-type polyoxoanions. Furthermore, both of the compounds exhibit photoluminescent properties at ambient temperature, and to elucidate the electronic properties of the metal ions (Cu 2+ or Cu 2+/Cr 3+), EPR studies have been performed, and the results are in good agreement with the structural feature of these compounds.

Zhang, Shiwei; Li, Yuxin; Liu, Ying; Cao, Ruige; Sun, Chunyan; Ji, Hongmei; Liu, Shuxia

2009-02-01

469

Long-range spatial correlations in one-dimensional Anderson models  

NASA Astrophysics Data System (ADS)

The study of metal-insulator transitions (MIT) in one-dimensional (1d) Anderson disordered systems remains an active topic of research. Analytic and numerical results have confirmed the scaling prediction on the absence of MIT for short-range correlated disorder potentials. Solutions for long-range correlated potential models (i.e. the dimer model and those with power-law spectral densities) have shown MITs in 1d. However, long-range correlations remain poorly understood. In order to gain some insight, we study a 1d Anderson model with disorder potential correlations described by a power-law model with = 1/(1 + r/a)^?. Here ?i, r, a, and ? are the on-site energy, position, lattice constant, and strength of the correlation respectively. We obtained results with various methods (wave packet diffusion, participatio ratio, transfer matrix and Green's function) that support the absence of a MIT in these models in. We further show that an analysis of the beta function provides evidence for the validity of the same one-parameter scaling law valid for short-range correlated potentials.

Petersen, Greg; Sandler, Nancy

2012-02-01

470

Optically excited states in positronium  

NASA Technical Reports Server (NTRS)

Optical excitation are reported of the 1 3S-2 3P transition in positronium, and a second excitation from n=2 to higher n states. The experiment used light from two pulsed dye lasers. Changes in the positronium annihilation rate during and after the laser pulse were used to deduce the excited state populations. The n=2 level was found to be saturable and excitable to a substantial fraction of n=2 positronium to higher levels. Preliminary spectroscopic measurements were performed on n=14 and n=15 positronium.

Howell, R. H.; Ziock, Klaus P.; Magnotta, F.; Dermer, Charles D.; Failor, R. A.; Jones, K. M.

1990-01-01

471

Plasmon excitation by slow ions  

NASA Astrophysics Data System (ADS)

We present a theoretical approach to the problem of subthreshold plasmon excitation in proton-aluminum collisions. Based both on recent experimental results by Ritzau [Phys. Rev. B 59, 15506 (1999)] and on previous calculations by two of the authors, we solve the master equations and obtain the probability of both plasmon excitation and nearly free electron excitation due to plasmon decay as functions of the projectile initial velocity. The mechanism considered for subthreshold plasmon excitation involves an intermediary fast electron as suggested by Ritzau

Bocan, G. A.; Arista, N. R.; Miraglia, J. E.

2007-01-01

472

Two-photon excited UV fluorescence for protein crystal detection  

PubMed Central

Two-photon excited ultraviolet fluorescence (TPE-UVF) microscopy is explored for sensitive protein-crystal detection as a complement to second-order nonlinear optical imaging of chiral crystals (SONICC). Like conventional ultraviolet fluorescence (UVF), TPE-UVF generates image contrast based on the intrinsic fluorescence of aromatic residues, generally producing higher fluorescence emission within crystals than the mother liquor by nature of the higher local protein concentration. However, TPE-UVF has several advantages over conventional UVF, including (i) insensitivity to optical scattering, allowing imaging in turbid matrices, (ii) direct compatibility with conventional optical plates and windows by using visible light for excitation, (iii) elimination of potentially damaging out-of-plane UV excitation, (iv) improved signal to noise through background reduction from out-of-plane excitation and (v) relatively simple integration into instrumentation developed for SONICC. PMID:21931215

Madden, Jeremy T.; DeWalt, Emma L.; Simpson, Garth J.

2011-01-01

473

Collective Dynamics for Network-Organized Identical Excitable Nodes  

NASA Astrophysics Data System (ADS)

We investigate the collective dynamics of network-organized identical excitable nodes. We theoretically analyze the stability of the rest state and propose that there are two different transition paths: the stationary path and the oscillatory path. We find that, although the onset of collective dynamics strongly depend on the network topology, the local dynamics and how local nodes interact with each other decide the transition path and the involved bifurcation.

Tao, Yu-Cheng; Cui, Ming-Zhu; Li, Hai-Hong; Yang, Jun-Zhong

2015-02-01

474

Eternal inflation and localization on the landscape  

SciTech Connect

We model essential features of eternal inflation on the landscape of a dense discretuum of vacua by the potential V({phi}) = V{sub 0}+{delta}V({phi}), where |{delta}V({phi})| << V{sub 0} is random. We find that the diffusion of the distribution function {rho}({phi},t) of the inflaton expectation value in different Hubble patches may be suppressed due to the effect analogous to the Anderson localization in disordered quantum systems. At late times only the localized part of the distribution function {rho}({phi},t) survives which leads to dynamical selection principle on the landscape. As a result, there exist such islands on the landscape that the probability to measure any but a small value of the cosmological constant in a given Hubble patch is exponentially suppressed.

Podolsky, Dmitry; Enqvist, Kari, E-mail: dmitry.podolsky@helsinki.fi, E-mail: kari.enqvist@helsinki.fi [Helsinki Institute of Physics, University of Helsinki, P.O.Box 64, FIN-00014 Helsinki (Finland)] [Helsinki Institute of Physics, University of Helsinki, P.O.Box 64, FIN-00014 Helsinki (Finland)

2009-02-15

475

Eternal inflation and localization on the landscape  

E-print Network

We model the essential features of eternal inflation on the landscape of a dense discretuum of vacua by the potential $V(\\phi)=V_{0}+\\delta V(\\phi)$, where $|\\delta V(\\phi)|\\ll V_{0}$ is random. We find that the diffusion of the distribution function $\\rho(\\phi,t)$ of the inflaton expectation value in different Hubble patches may be suppressed due to the effect analogous to the Anderson localization in disordered quantum systems. At $t \\to \\infty$ only the localized part of the distribution function $\\rho (\\phi, t)$ survives which leads to dynamical selection principle on the landscape. The probability to measure any but a small value of the cosmological constant in a given Hubble patch on the landscape is exponentially suppressed at $t\\to \\infty$.

D. Podolsky; K. Enqvist

2007-09-18

476

The Excitable Membrane  

PubMed Central

The model of the excitable membrane assumes common channels for Na+ and K+; the two ion species interact within the pores through their electrostatic forces. The electric field varies across the membrane and with time, as a result of ionic redistribution. Ionic flow is primarily controlled by energy barriers at the two interfaces and by Ca++ adsorption at the external interface. When the membrane is polarized, the high electric field at the external interface acting on the membrane fixed charge keeps the effective channel diameter small, so that only dihydrated ions can cross the interface. The higher energy required to partially dehydrate Na+ accounts for its lower permeability when polarized. Depolarized, the channel entrance can expand, permitting quadrihydrated ions to pass; the large initial Na+ flow is the result of the large concentration ratio across the interface. The effect at the internal interface is symmetric; Na+ crosses with greater difficulty when the membrane is depolarized. Na+ inactivation occurs when the ion distribution within the membrane has assumed its new steady-state value. Calculations based on parameters consistent with physicochemical data agree generally with a wide range of experiments. The model does not obey the two fundamental Hodgkin-Huxley (HH) postulates (independence principle, ion flow proportional to thermodynamic potential). In several instances the model predicts experimental results which are not predicted by the HH equations. ImagesFIGURE 12 PMID:4655662

Offner, Franklin F.

1972-01-01

477

Excited waves in shear layers  

NASA Technical Reports Server (NTRS)

The generation of instability waves in free shear layers is investigated. The model assumes an infinitesimally thin shear layer shed from a semi-infinite plate which is exposed to sound excitation. The acoustical shear layer excitation by a source further away from the plate edge in the downstream direction is very weak while upstream from the plate edge the excitation is relatively efficient. A special solution is given for the source at the plate edge. The theory is then extended to two streams on both sides of the shear layer having different velocities and densities. Furthermore, the excitation of a shear layer in a channel is calculated. A reference quantity is found for the magnitude of the excited instability waves. For a comparison with measurements, numerical computations of the velocity field outside the shear layer were carried out.

Bechert, D. W.

1982-01-01

478

Mike's Graduate Reading List Anderson, D. R., K. P. Burnham, and William L. Thompson. 2000. Null hypothesis testing: problems,  

E-print Network

. Cooper, J. G. Cox, D. R. Coyle, R. J. Fisher, J. D. Hoffman, and J. J. Storm. 2008. Statistical confusionMike's Graduate Reading List Essential: Anderson, D. R., K. P. Burnham, and William L. Thompson.A. Estes, B.S. Halpern, U. Jacob, D.r. Lindberg, J. Lovvorn, D.H. Monson, M.T. Tinker, T.M. Williams, J

Mitchell, Mike

479

Nuclear liability insurance: the Price-Anderson reparations system and the claims experience of the nuclear industry  

Microsoft Academic Search

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

Marrone

1983-01-01

480

MD Anderson preclinical study identifies 'master' proto-oncogene that regulates stress-induced ovarian cancer metastasis  

Cancer.gov

Scientists at The University of Texas MD Anderson Cancer Center have discovered the signaling pathway whereby a master regulator of cancer cell proteins -- known as Src -- leads to ovarian cancer progression when exposed to stress hormones. The researchers report in the current issue of Nature Communications that beta blocker drugs mitigate this effect and reduce cancer deaths by an average of 17 percent.

481

Proposal for Themester 2012: Good Behavior, Bad Behavior Instructor: Penelope Anderson, Assistant Professor of English [pea@indiana.edu  

E-print Network

1 Proposal for Themester 2012: Good Behavior, Bad Behavior Instructor: Penelope Anderson, Assistant of Shakespeare" foregrounds the relevance of perspective and interpretation to the Themester focus on good and Villains in the Early Plays of Shakespeare" We think of the battle between good and evil as the very

Indiana University

482

MD Anderson study finds drug combination improves progression-free survival for women with metastatic breast cancer:  

Cancer.gov

In an international Phase III randomized study, everolimus, when combined with the hormonal therapy exemestane, has been shown to dramatically improve progression-free survival for women with metastatic breast cancer, according to research from The University of Texas MD Anderson Cancer Center.

483

Scale-Dependent Reproduction of Pen-and-Ink Illustrations Mike Salisbury Corin Anderson Dani Lischinski David H. Salesin  

E-print Network

Scale-Dependent Reproduction of Pen-and-Ink Illustrations Mike Salisbury Corin Anderson Dani This paper describes a representation for pen-and-ink illustrations that allows the creation of high-fidelity illustrations at any scale or resolution. We represent a pen-and-ink illustration as a low-reso- lution grey

Washington at Seattle, University of

484

Interactive Pen-and-Ink Illustration Michael P. Salisbury Sean E. Anderson Ronen Barzel3 David H. Salesin  

E-print Network

Interactive Pen-and-Ink Illustration Michael P. Salisbury Sean E. Anderson Ronen Barzel3 David H for creating pen-and-ink illustra- tions. The system uses stroke textures--collections of strokes ar- ranged-photorea- listic rendering, prioritized stroke textures. 1 Introduction Pen-and-ink is an extremely limited medium

Washington at Seattle, University of

485

The AI Technologies of the Philadelphia Area Urban Wireless Network Testbed Gustave Anderson and Andrew Burnheimer and Vincent Cicirello  

E-print Network

The AI Technologies of the Philadelphia Area Urban Wireless Network Testbed Gustave Anderson Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104 Introduction Drexel University's College a Philadelphia Area Urban Wireless Network Testbed (PA-UWNT) (Cicirello et al. 2004). The PA- UWNT is a mobile ad

Cicirello, Vincent A.

486

Chemistry Professor Larry Anderson teaches his students to look at the big picture when it comes to research about  

E-print Network

·. Chemistry Professor Larry Anderson teaches his students to look at the big picture when way his chemistry students learn. "The goal is to get the students to think critically," he says. "It in an effort to help the country reduce its dependence on petroleum and to decrease greenhouse gases. Last year

487

www.water-alternatives.org Volume 7 | Issue 2 Bauer, C. 2014. Book review of Anderson et al. 2012.  

E-print Network

the following structure [with my notes in brackets]: 1. Water crisis [the problem: scarcity, conflict, demandswww.water-alternatives.org Volume 7 | Issue 2 Bauer, C. 2014. Book review of Anderson et al. 2012. Tapping water markets. RFF Press/Routledge. Water Alternatives 7(2): 436-438 Book Review: Tapping water

488

Ion-temperature-gradient modes in stellarator geometry (T Rafiq, J Anderson, M Nadeem and M Persson)  

E-print Network

Ion-temperature-gradient modes in stellarator geometry (T Rafiq, J Anderson, M Nadeem and M Persson Göteborg, Sweden) The stability of the ion-temperature gradient mode has been examined in the short calculations have been presented on field line of reference at $\\theta =\\zeta =0$ on the magnetic surface $s=0

489

MD Anderson study finds SUMO-snipping protein plays crucial role in T and B cell development  

Cancer.gov

When SUMO grips STAT5, a protein that activates genes, it blocks the healthy embryonic development of immune B cells and T cells unless its nemesis breaks the hold, a research team led by scientists at The University of Texas MD Anderson Cancer Center reports in Molecular Cell.

490

COMBINATORIAL PROOFS OF FERMAT'S, LUCAS'S, AND WILSON'S PETER G. ANDERSON, ARTHUR T. BENJAMIN, AND JEREMY A. ROUSE  

E-print Network

COMBINATORIAL PROOFS OF FERMAT'S, LUCAS'S, AND WILSON'S THEOREMS PETER G. ANDERSON, ARTHUR T case where b = 0, it is clear that Vp = ap . Consequently, we have Fermat's Theorem: If p is a prime, then ap a (mod p). This combinatorial proof of Fermat's theorem was originally given in [2]. Next

Anderson, Peter G.

491

MD Anderson researchers find that breast cancer patients with BRCA gene are diagnosed almost 8 years earlier than generation before  

Cancer.gov

Women with a deleterious gene mutation are diagnosed with breast cancer almost eight years earlier than relatives of the previous generation who also had the disease and/or ovarian cancer, according to new research from the University of Texas MD Anderson Cancer Center.

492

Small Noise Methods for Risk-Sensitive/Robust Economies$ Evan W. Anderson,a, Lars Peter Hansenb, Thomas J. Sargentc  

E-print Network

Small Noise Methods for Risk-Sensitive/Robust Economies$ Evan W. Anderson,a, Lars Peter Hansenb at The University of North Carolina, North Carolina State, and The University of Virginia as well as participants-hansen@uchicago.edu (Lars Peter Hansen), thomas.sargent@nyu.edu (Thomas J. Sargent) Preprint submitted to Elsevier June 13

Hansen, Lars Peter

493

Program Spotlight: University of Puerto Rico and MD Anderson Partnership Welcomes Its First Graduates, Dedicated to Researching Cancer Health Disparities  

Cancer.gov

CRCHD joins the Principal Investigators and Diversity Training co-leaders of the University of Puerto Rico and the University of Texas MD Anderson Cancer Center U54 Partnership for Excellence in Cancer Research in congratulating its first MDPhD graduates Sergei Gumá-de La Vega and Nahir Cortés-Santiago.

494

Low-Power Programmable FPGA Routing Circuitry Jason H. Anderson, Member, IEEE, and Farid N. Najm, Fellow, IEEE  

E-print Network

in recent technology generations. Subthreshold leakage current flows between the source and drain terminals1 Low-Power Programmable FPGA Routing Circuitry Jason H. Anderson, Member, IEEE, and Farid N. Najm a family of new FPGA routing switch designs that are programmable to operate in three different modes: high

Najm, Farid N.