7,232 research outputs found
An Exact Solution for the Lattice Gas Model in One Dimension
A simple method to obtain a canonical partition function for one dimensional
lattice gas model is presented. The simplification is based upon rewriting a
sum over all possible configurations to a sum over numbers of clusters in the
system.Comment: 6 pages, LaTe
Effects of spin polarization on resonant photoemission from d-f states in TbNi2Mnx compounds
Resonant photoemission in narrow-band materials is described by the sum of first-and secondorder transitions, their quantum-mechanical interference leads to an increase in the spectrum from the valence bands and the appearance of an asymmetric dependence on the photon energy. These effects are studied theoretically and experimentally using the example of three-component intermetallic compounds TbNi2Mnx. The competition between the elastic and inelastic photoemission channels leads to a different dependence of photoemission spectra from nickel and manganese on photon energy. The elastic channel is realized on atoms with large magnetic moments, the inelastic Auger decay occurs on atoms with small moments. © 2018 The Authors, published by EDP Sciences.The research was carried out within the state assignment of FASO of Russia (theme uQ" ant" No. 01201463332), supported in part by RFBR (No. 18-02-00060) and UD RAS (No.15 -8 2-10). The authors express their gratitude to A. Preobrazhenskii and N. Vinogradov (synchrotron MAX-Lab, Lund, Sweden) for their assistance in carrying out experiments
The influence of motor activity on the development of cardiac arrhythmias during experimental emotional stress
Experimental emotional stress which can produce various disorders of cardiac rhythm: sinus tachycardia, atrial fibrillation, ventricular, extrasystoles and paroxysmal ventricular tachysystoles was studied. In these conditions the adrenalin content in the blood and myocardium is increased 3 to 4 times. It is found that moderate motor activity leads to a relative decrease of adrenalin in the myocardium and arrest of cardiac arrhythmias
On Graph-Theoretic Identifications of Adinkras, Supersymmetry Representations and Superfields
In this paper we discuss off-shell representations of N-extended
supersymmetry in one dimension, ie, N-extended supersymmetric quantum
mechanics, and following earlier work on the subject codify them in terms of
certain graphs, called Adinkras. This framework provides a method of generating
all Adinkras with the same topology, and so also all the corresponding
irreducible supersymmetric multiplets. We develop some graph theoretic
techniques to understand these diagrams in terms of a relatively small amount
of information, namely, at what heights various vertices of the graph should be
"hung".
We then show how Adinkras that are the graphs of N-dimensional cubes can be
obtained as the Adinkra for superfields satisfying constraints that involve
superderivatives. This dramatically widens the range of supermultiplets that
can be described using the superspace formalism and organizes them. Other
topologies for Adinkras are possible, and we show that it is reasonable that
these are also the result of constraining superfields using superderivatives.
The family of Adinkras with an N-cubical topology, and so also the sequence
of corresponding irreducible supersymmetric multiplets, are arranged in a
cyclical sequence called the main sequence. We produce the N=1 and N=2 main
sequences in detail, and indicate some aspects of the situation for higher N.Comment: LaTeX, 58 pages, 52 illustrations in color; minor typos correcte
Foreign Language Studies in Higher Education as a Means of Forming a Humanitarian Culture of Students
В статье рассматривается проблема формирования гуманитарной культуры студентов при изучении иностранного языка в системе учебно-воспитательного процесса высшего учебного заведения. В наши дни одной из основных задач образования является формирование позитивных духовных качеств учащихся, способствующих развитию и гармонизации межкультурных отношений. Профессиональный и личностный потенциал преподавателя выполняет важную роль в гуманитарной подготовке студентов, имеющий своей конечной целью формирование целостного мировоззрения, социализацию и инкультурацию личности. В работе рассматриваются значимость и основные критерии развития гуманитарного образования в учебном процессе. Иностранный язык как многоуровневое средство коммуникации между людьми играет важную роль в формировании у студентов внутренней гуманитарной культуры. Формирование социокультурной толерантности невозможно без лингвострановедческой компетенции. Языковой материал, который отражает ценностные ориентиры и факты культуры изучаемого языка, включающий в себя безэквивалентную и фоновую лексику, коннотативные лексические единицы, узуальные формы речи является основным средством поставленной цели.The article deals with the problem of the formation of the humanitarian culture of students in the study of a foreign language in the educational process of a higher educational institution. Today, one of the main tasks of education is the formation of positive spiritual qualities of students, contributing to the development and harmonization of intercultural relations. The professional and personal potential of the teacher plays an important role in the humanitarian training of students, with the ultimate goal of forming an integral worldview, socialization and inculturation of the individual. The work examines the significance and main criteria for the development of liberal arts education in the educational process. A foreign language as a multilevel means of communication between people plays an important role in the formation of students' internal humanitarian culture. The formation of socio-cultural tolerance is impossible without linguistic and cultural competence. The linguistic material, which reflects the value orientations and facts of the culture of the studied language, including non-equivalent and background vocabulary, connotative lexical units, conventional forms of speech, is the main means of the goal
Heavy Flavor Hadrons in Statistical Hadronization of Strangeness-rich QGP
We study b, c quark hadronization from QGP. We obtain the yields of charm and
bottom flavored hadrons within the statistical hadronization model. The
important novel feature of this study is that we take into account the high
strangeness and entropy content of QGP, conserving strangeness and entropy
yields at hadronization.Comment: v2 expended: 20 pages, 23 figures, 5 tables, in press EPJ-
Electrostatic Conveyer for Excitons
We report on the study of indirect excitons in moving lattices - conveyers
created by a set of AC voltages applied to the electrodes on the sample
surface. The wavelength of this moving lattice is set by the electrode
periodicity, the amplitude is controlled by the applied voltage, and the
velocity is controlled by the AC frequency. We observed the dynamical
localization-delocalization transition for excitons in the conveyers and
measured its dependence on the exciton density and conveyer amplitude and
velocity. We considered a model for exciton transport via conveyers. The
theoretical simulations are in agreement with the experimental data.Comment: 4 pages, 4 figures + supplemental material including two video
Generation of coherent terahertz pulses in Ruby at room temperature
We have shown that a coherently driven solid state medium can potentially
produce strong controllable short pulses of THz radiation. The high efficiency
of the technique is based on excitation of maximal THz coherence by applying
resonant optical pulses to the medium. The excited coherence in the medium is
connected to macroscopic polarization coupled to THz radiation. We have
performed detailed simulations by solving the coupled density matrix and
Maxwell equations. By using a simple -type energy scheme for ruby, we have
demonstrated that the energy of generated THz pulses ranges from hundreds of
pico-Joules to nano-Joules at room temperature and micro-Joules at liquid
helium temperature, with pulse durations from picoseconds to tens of
nanoseconds. We have also suggested a coherent ruby source that lases on two
optical wavelengths and simultaneously generates THz radiation. We discussed
also possibilities of extension of the technique to different solid-state
materials
Ethnic differences in proximal and distal tubular sodium reabsorption are heritable in black and white populations.
BACKGROUND: Segmental handling of sodium along the proximal and distal nephron might be heritable and different between black and white participants.
METHODS: We randomly recruited 95 nuclear families of black South African ancestry and 103 nuclear families of white Belgian ancestry. We measured the (FENa) and estimated the fractional renal sodium reabsorption in the proximal (RNaprox) and distal (RNadist) tubules from the clearances of endogenous lithium and creatinine. In multivariable analyses, we studied the relation of RNaprox and RNadist with FENa and estimated the heritability (h) of RNaprox and RNadist.
RESULTS: Independent of urinary sodium excretion, South Africans (n = 240) had higher RNaprox (unadjusted median, 93.9% vs. 81.0%; P < 0.001) than Belgians (n = 737), but lower RNadist (91.2% vs. 95.1%; P < 0.001). The slope of RNaprox on FENa was steeper in Belgians than in South Africans (-5.40 +/- 0.58 vs. -0.78 +/- 0.58 units; P < 0.001), whereas the opposite was true for the slope of RNadist on FENa (-3.84 +/- 0.19 vs. -13.71 +/- 1.30 units; P < 0.001). h of RNaprox and RNadist was high and significant (P < 0.001) in both countries. h was higher in South Africans than in Belgians for RNaprox (0.82 vs. 0.56; P < 0.001), but was similar for RNadist (0.68 vs. 0.50; P = 0.17). Of the filtered sodium load, black participants reabsorb more than white participants in the proximal nephron and less postproximally.
CONCLUSION: Segmental sodium reabsorption along the nephron is highly heritable, but the capacity for regulation in the proximal and postproximal tubules differs between whites and blacks
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