1,448 research outputs found
Regular Incidence Complexes, Polytopes, and C-Groups
Regular incidence complexes are combinatorial incidence structures
generalizing regular convex polytopes, regular complex polytopes, various types
of incidence geometries, and many other highly symmetric objects. The special
case of abstract regular polytopes has been well-studied. The paper describes
the combinatorial structure of a regular incidence complex in terms of a system
of distinguished generating subgroups of its automorphism group or a
flag-transitive subgroup. Then the groups admitting a flag-transitive action on
an incidence complex are characterized as generalized string C-groups. Further,
extensions of regular incidence complexes are studied, and certain incidence
complexes particularly close to abstract polytopes, called abstract polytope
complexes, are investigated.Comment: 24 pages; to appear in "Discrete Geometry and Symmetry", M. Conder,
A. Deza, and A. Ivic Weiss (eds), Springe
Оптимизация нормированной переходной функции линейной цепи, описываемой характеристическим уравнением 4-го порядка
Определение параметров усилительной схемы, обеспечивающих наилучшую форму переходной характеристики, является одной из наиболее сложных задач усилительной техники. При наличии нескольких варьируемых параметров, т. е. при характеристических уравнениях выше второй степени, задача значительно усложняется и случайным варьированием или машинным перебором сочетаний параметров решить ее чрезвычайно трудно. С целью значительного сокращения усилий и времени, затрачиваемых на решение подобных задач, разработаны алгоритм и методика определения с помощью цифровых ЭВМ оптимальных значений коэффициентов коррекции переходных функций линейных целей, описываемых характеристическими уравнениями 2-й и 4-й степеней, при заданных значениях первого и второго выбросов. Приведены графики, иллюстрирующие результаты вычислений
Модифицирование матриксов из поли-L-молочной кислоты импульсным сильноточным электронным пучком
We describe the synthesis, characterisation and surface-modification of magnetic narroparticles and a poly(N-isopropylacrylamide) microgel, followed by the assembly and characterisation of magnetic nanoparticles on the microgel. To facilitate this deposition, the surface of the microgel is first modified via the layer-by-layer assembly of polyelectrolytes. One advantage of this concept is that it allows an independent optimization and fine tuning of the magnetic and thermoresponsive properties of individual components (nanoparticles and microgels) before assembling them so that the hybrid core-shell structure retains all the individual properties. The,decisive parameter when exploiting the thermoresponsive and magnetic properties in such hybrid core-shell structures is the amount of heat transfer from the magnetic core onto the thermosensitive (loaded) microgel (for the subsequent heat-triggered release of drugs). Inductive heat study reveals that the heat generated by the magnetic narroparticles is sufficient to cause the collapse of the microgel above its volume phase transition temperature. Successful confinement of positively and negatively charged magnetic nanoparticles between polyelectrolyte layers is achieved using the layer-by-layer deposition onto the microgel. Dynamic light scattering measurements show (i) the presence of each layer successfully deposited, (ii) the preservation of thermoresponsivity in the coated microgel, and (iii) that the magnetic nanoparticles do not get detached during the phase transition of the microgel. Electrophoresis measurements confirm charge reversal at every stage of layering of polycations, polyanions and magnetic nanoparticles. This unique combination of thermoresponsivity and magnetism opens up novel perspectives towards remotely controlled drug carriers. (c) 200
Система управления персоналом в организации "Ростелеком"
Объект ВКР - система управления персоналом.
Цель ВКР – определение особенности сущности концепта "система управления персоналом предприятия", его целей, задач и свойств.
В процессе исследования проводились социологические исследования.
В результате исследования были разработаны несколько мероприятий по совершенствованию системы управления персоналом.
Основные конструктивные, технологические и управленческие характеристики: исследуемое предприятие ПАО "Ростелеком" имеет большую численность персонала, а также подвержено высокой текучести кадров по причине неэффективной системы управления персоналом.
Степень внедрения: разработанные мероприятия по совершенствованию системы управления персоналом применены и используются в ПАО "Ростелеком".The object of the study is (are) - PJSC "Rostelecom".
The purpose of the work is to define the essence of the concept of the "hr-management system of the enterprise", its goals, tasks and properties.
In the process of research were conducted sociological methods of studying.
As a result of the research, several measures were developed to improve the hr-management system.
The main design, technological and management characteristics: the company PJSC "Rostelecom" has a large number of employees, and has problems with high staff turnover due to inefficient hr-management system.
Degree of implementation: the developed measures to improve the personnel management system are applied and used in PJSC "Rostelecom"
Определение кинетических параметров процесса каталитического крекинга
This study describes a facile two-step approach to modify the surface of nanoparticles, thereby imparting a core-shell structure to the system. The core consists of magnetic nanoparticles and the shell is composed of thermo responsive hydroxypropyl cellulose, using a coupling agent to covalently bind the core to the shell. Hydroxypropyl cellulose is known for its biocompatibility and biodegradability, and its thermoresponsive properties make it an excellent candidate for fabricating biocompatible stimuli-responsive magnetic nanoparticles. We report the synthesis of magnetic nanoparticles and the successful binding of the polymer to them. X-ray diffraction studies show that the surface modification of the magnetic nanoparticles does not result in any phase change and the size of the magnetic core thus calculated (7 nm) reveals that such hybrid core-shell system is superparamagnetic in nature, as further confirmed by magnetization measurements. The size obtained by X-ray diffraction is in good agreement with that obtained by transmission electron microscope. Evidence of binding is given by Fourier transform infrared spectroscopy and a quantitative analysis of the polymeric content obtained by thermogravimetry analysis. Dynamic light scattering as a function of temperature reveals the thermoresponsive behavior of the particles with a lower critical solution temperature around 41 degrees C, which is also the temperature at which cellulose undergoes a coil-to-globule transition
Decreased STARD10 expression is associated with defective insulin secretion in humans and mice
Genetic variants near ARAP1 (CENTD2) and STARD10 influence type 2 diabetes (T2D) risk. The risk alleles impair glucose-induced insulin secretion and, paradoxically but characteristically, are associated with decreased proinsulin:insulin ratios, indicating improved proinsulin conversion. Neither the identity of the causal variants nor the gene(s) through which risk is conferred have been firmly established. Whereas ARAP1 encodes a GTPase activating protein, STARD10 is a member of the steroidogenic acute regulatory protein (StAR)-related lipid transfer protein family. By integrating genetic fine-mapping and epigenomic annotation data and performing promoter-reporter and chromatin conformational capture (3C) studies in β cell lines, we localize the causal variant(s) at this locus to a 5 kb region that overlaps a stretch-enhancer active in islets. This region contains several highly correlated T2D-risk variants, including the rs140130268 indel. Expression QTL analysis of islet transcriptomes from three independent subject groups demonstrated that T2D-risk allele carriers displayed reduced levels of STARD10 mRNA, with no concomitant change in ARAP1 mRNA levels. Correspondingly, β-cell-selective deletion of StarD10 in mice led to impaired glucose-stimulated Ca2+ dynamics and insulin secretion and recapitulated the pattern of improved proinsulin processing observed at the human GWAS signal. Conversely, overexpression of StarD10 in the adult β cell improved glucose tolerance in high fat-fed animals. In contrast, manipulation of Arap1 in β cells had no impact on insulin secretion or proinsulin conversion in mice. This convergence of human and murine data provides compelling evidence that the T2D risk associated with variation at this locus is mediated through reduction in STARD10 expression in the β cell
What You Find Depends on How You Measure It: Reactivity of Response Scales Measuring Predecisional Information Distortion in Medical Diagnosis
“Predecisional information distortion” occurs when decision makers evaluate new information in a way that is biased towards their leading option. The phenomenon is well established, as is the method typically used to measure it, termed “stepwise evolution of preference” (SEP). An inadequacy of this method has recently come to the fore: it measures distortion as the total advantage afforded a leading option over its competitor, and therefore it cannot differentiate between distortion to strengthen a leading option (“proleader” distortion) and distortion to weaken a trailing option (“antitrailer” distortion). To address this, recent research introduced new response scales to SEP. We explore whether and how these new response scales might influence the very proleader and antitrailer processes that they were designed to capture (“reactivity”). We used the SEP method with concurrent verbal reporting: fifty family physicians verbalized their thoughts as they evaluated patient symptoms and signs (“cues”) in relation to two competing diagnostic hypotheses. Twenty-five physicians evaluated each cue using the response scale traditional to SEP (a single response scale, returning a single measure of distortion); the other twenty-five did so using the response scales introduced in recent studies (two separate response scales, returning two separate measures of distortion: proleader and antitrailer). We measured proleader and antitrailer processes in verbalizations, and compared verbalizations in the single-scale and separate-scales groups. Response scales did not appear to affect proleader processes: the two groups of physicians were equally likely to bolster their leading diagnosis verbally. Response scales did, however, appear to affect antitrailer processes: the two groups denigrated their trailing diagnosis verbally to differing degrees. Our findings suggest that the response scales used to measure information distortion might influence its constituent processes, limiting their generalizability across and beyond experimental studies
Sexual Size Dimorphism and Body Condition in the Australasian Gannet
Funding: The research was financially supported by the Holsworth Wildlife Research Endowment. Acknowledgments We thank the Victorian Marine Science Consortium, Sea All Dolphin Swim, Parks Victoria, and the Point Danger Management Committee for logistical support. We are grateful for the assistance of the many field volunteers involved in the study.Peer reviewedPublisher PD
Optical Lattices: Theory
This chapter presents an overview of the properties of a Bose-Einstein
condensate (BEC) trapped in a periodic potential. This system has attracted a
wide interest in the last years, and a few excellent reviews of the field have
already appeared in the literature (see, for instance, [1-3] and references
therein). For this reason, and because of the huge amount of published results,
we do not pretend here to be comprehensive, but we will be content to provide a
flavor of the richness of this subject, together with some useful references.
On the other hand, there are good reasons for our effort. Probably, the most
significant is that BEC in periodic potentials is a truly interdisciplinary
problem, with obvious connections with electrons in crystal lattices, polarons
and photons in optical fibers. Moreover, the BEC experimentalists have reached
such a high level of accuracy to create in the lab, so to speak, paradigmatic
Hamiltonians, which were first introduced as idealized theoretical models to
study, among others, dynamical instabilities or quantum phase transitions.Comment: Chapter 13 in Part VIII: "Optical Lattices" of "Emergent Nonlinear
Phenomena in Bose-Einstein Condensates: Theory and Experiment," edited by P.
G. Kevrekidis, D. J. Frantzeskakis, and R. Carretero-Gonzalez (Springer
Series on Atomic, Optical, and Plasma Physics, 2007) - pages 247-26
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