195 research outputs found

    Dynamical localization, measurements and quantum computing

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    We study numerically the effects of measurements on dynamical localization in the kicked rotator model simulated on a quantum computer. Contrary to the previous studies, which showed that measurements induce a diffusive probability spreading, our results demonstrate that localization can be preserved for repeated single-qubit measurements. We detect a transition from a localized to a delocalized phase, depending on the system parameters and on the choice of the measured qubit.Comment: 4 pages, 4 figures, research at Quantware MIPS Center http://www.quantware.ups-tlse.f

    A Case of Primary Amyloidosis Involving Liver, Stomach, Intestines, and Heart without Evident Kidney Involvement

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    Aim. Systemic amyloidosis caused by the synthesis and deposition of immunoglobulin light chains (AL amyloidosis) is a relatively rare disease that involves heart, kidneys, peripheral nervous system, gastrointestinal tract, and has a large number of various clinical manifestations. We present a clinical case of systemic AL amyloidosis with a predominant involvement of liver, stomach, intestines, and heart in a Caucasian female.Key points. A Caucasian woman presented to clinic with severe general weakness, abdominal pain, diarrhea, sudden weight loss, and palpitation. Initial examination revealed a duodenal bulb ulcer complicated by bleeding and polyps in the retrobulbar part of duodenum. Decreased hemoglobin levels, elevated levels of alkaline phosphatase, gamma-glutamyltransferase, and N-terminal prohormone of brain natriuretic peptide, signs of heart failure with preserved ejection fraction, and hepatomegaly became the basis for a clinical suspicion of AL amyloidosis and puncture liver biopsy. Histochemical and immunohistochemical studies of liver, stomach, and duodenum biopsy specimens confirmed AL amyloidosis. Timely diagnosis made it possible to conduct a specific therapy with melphalan plus dexamethasone, get a satisfactory response and improve the patient’s condition.Conclusion. A thorough examination of patients along with a pathomorphological and immunohistochemical study of the biopsy specimens is the basis for confirming the diagnosis of AL amyloidosis, selecting the proper therapy, improving the condition of patients and their survival

    Dynamics of some piecewise smooth Fermi-Ulam Models

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    We find a normal form which describes the high energy dynamics of a class of piecewise smooth Fermi-Ulam ping pong models; depending on the value of a single real parameter, the dynamics can be either hyperbolic or elliptic. In the first case we prove that the set of orbits undergoing Fermi acceleration has zero measure but full Hausdorff dimension. We also show that for almost every orbit the energy eventually falls below a fixed threshold. In the second case we prove that, generically, we have stable periodic orbits for arbitrarily high energies, and that the set of Fermi accelerating orbits may have infinite measure.Comment: 22 pages, 4 figure

    Chaos, Fractals and Inflation

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    In order to draw out the essential behavior of the universe, investigations of early universe cosmology often reduce the complex system to a simple integrable system. Inflationary models are of this kind as they focus on simple scalar field scenarios with correspondingly simple dynamics. However, we can be assured that the universe is crowded with many interacting fields of which the inflaton is but one. As we describe, the nonlinear nature of these interactions can result in a complex, chaotic evolution of the universe. Here we illustrate how chaotic effects can arise even in basic models such as homogeneous, isotropic universes with two scalar fields. We find inflating universes which act as attractors in the space of initial conditions. These universes display chaotic transients in their early evolution. The chaotic character is reflected by the fractal border to the basin of attraction. The broader implications are likely to be felt in the process of reheating as well as in the nature of the cosmic background radiation.Comment: 16 pages, RevTeX. See published version for fig

    Fractal Spin Glass Properties of Low Energy Configurations in the Frenkel-Kontorova chain

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    We study numerically and analytically the classical one-dimensional Frenkel-Kontorova chain in the regime of pinned phase characterized by phonon gap. Our results show the existence of exponentially many static equilibrium configurations which are exponentially close to the energy of the ground state. The energies of these configurations form a fractal quasi-degenerate band structure which is described on the basis of elementary excitations. Contrary to the ground state, the configurations inside these bands are disordered.Comment: revtex, 9 pages, 9 figure

    Narcissism and the Strategic Pursuit of Short-Term Mating: Universal Links across 11 World Regions of the International Sexuality Description Project-2

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    Previous studies have documented links between sub-clinical narcissism and the active pursuit of short-term mating strategies (e.g., unrestricted sociosexuality, marital infidelity, mate poaching). Nearly all of these investigations have relied solely on samples from Western cultures. In the current study, responses from a cross-cultural survey of 30,470 people across 53 nations spanning 11 world regions (North America, Central/South America, Northern Europe, Western Europe, Eastern Europe, Southern Europe, Middle East, Africa, Oceania, Southeast Asia, and East Asia) were used to evaluate whether narcissism (as measured by the Narcissistic Personality Inventory; NPI) was universally associated with short-term mating. Results revealed narcissism scores (including two broad factors and seven traditional facets as measured by the NPI) were functionally equivalent across cultures, reliably associating with key sexual outcomes (e.g., more active pursuit of short-term mating, intimate partner violence, and sexual aggression) and sex-related personality traits (e.g., higher extraversion and openness to experience). Whereas some features of personality (e.g., subjective well-being) were universally associated with socially adaptive facets of Narcissism (e.g., self-sufficiency), most indicators of short-term mating (e.g., unrestricted sociosexuality and marital infidelity) were universally associated with the socially maladaptive facets of narcissism (e.g., exploitativeness). Discussion addresses limitations of these cross-culturally universal findings and presents suggestions for future research into revealing the precise psychological features of narcissism that facilitate the strategic pursuit of short-term mating

    When is identity congruent with the self? A self-determination theory perspective

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    Within the identity literature, self and identity are often used as interchangeable terms. By contrast, in Self-Determination Theory (SDT; Ryan & Deci, 2003) both terms have a differentiated meaning and it is maintained that identities may vary in the extent to which they are congruent with the basic growth tendencies of the self that are fueled by the basic psychological needs for autonomy, competence, and relatedness. Specifically, the level of congruence between identities and the self is said to depend on (a) the motives underlying one’s identity commitments (i.e., pressure versus volition) and (b) the content of the goals defining one’s identity (i.e., extrinsic versus intrinsic). It is argued in SDT that both the motives and the goals behind one’s identity are important for optimal functioning because of their linkage with basic need satisfaction. This chapter (a) compares the SDT view on identity development with prevailing models of identity formation, and with constructivist models of identity in particular, and (b) reviews research relevant to the idea that identities need to be congruent with the self in order to foster well-being and adjustment

    Cultural distance, mindfulness and passive xenophobia: Using Integrated Threat Theory to explore home higher education students' perspectives on 'internationalisation at home'

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    This paper addresses the question of interaction between home and international students using qualitative data from 100 home students at two 'teaching intensive' universities in the southwest of England. Stephan and Stephan's Integrated Threat Theory is used to analyse the data, finding evidence for all four types of threat that they predict when outgroups interact. It is found that home students perceive threats to their academic success and group identity from the presence of international students on the campus and in the classroom. These are linked to anxieties around 'mindful' forms of interaction and a taboo around the discussion of difference, leading to a 'passive xenophobia' for the majority. The paper concludes that Integrated Threat Theory is a useful tool in critiquing the 'internationalisation at home' agenda, making suggestions for policies and practices that may alleviate perceived threats, thereby improving the quality and outcomes of intercultural interaction. © 2010 British Educational Research Association

    High power ECRH and ECCD in moderately collisional ASDEX upgrade H-modes and status of EC system upgrade

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    This contribution deals with H-modes with significant heat exchange between electrons and ions, but which can still show large differences between electron and ion-temperatures especially inside half minor radius. These conditions are referred to as moderately collisional. A systematic study shows that an increasing fraction of electron heating increases the transport in the ion channel mainly due to the dependence of the ITG dominated ion transport on the ratio Te/Ti in agreement with modeling. The rotational shear in the plasmas under study was so small that it hardly influences ITG stability, such that variations of the rotation profile due to a change of the heating method were of minor importance. These findings connect to studies of advanced tokamak scenarios using ECCD as a tool to modify the q-profile. The electron heating connected to the ECCD tends to increase the transport in the ion channel quite in contrast to the goal to operate at reduced current but with increased confinement. The confinement only increases as the fraction of ion heating is increased by adding more NBI. An ITER case was modeled as well. Due to the larger value of νei ・ τE the ratio Te/Ti is only moderately reduced even with strong electron heating and the confinement reduction is small even for the hypothetic case of using only ECRH as additional heating. Finally the paper discusses the ongoing upgrade of the AUG ECRH-system
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