650 research outputs found
Polymorphic phase transitions and ferroelectric properties in β-glycine single crystals and micro islands
The research was carried out using equipment of Ural Center for Shared Use "Modern Nanotechnologies" Ural Federal University with the financial support by the Government of the Russian Federation (Resolution 211, Contract 02.A03.21.0006). The reported study was funded by RFBR according to the research project № 18-32-00390
Energy harvesting from nanofibers of hybrid organic ferroelectric dabcoHReO(4)
We report excellent piezoelectric and pyroelectric properties of electrospun nanofibers based on the hybrid ferroelectric 1,4-diazabicyclo[2.2.2]octane perrhenate (dabcoHReO(4)). Ferroelectric nanoparticles are embedded into the fibers being naturally aligned with the major polarization component along the fiber axis. A flexible piezoelectric nanogenerator consisting of an aligned array of dabcoHReO(4) fibers provides a voltage above 100 mV under a moderate strain level. The pyroelectric coefficient in as-electrospun dabcoHReO(4) fiber mat is similar to that in poled polyvinylidene difluoride nanofibers. The results show that the nanofibers based on dabcoHReO(4) have a great potential for pyroelectric and piezoelectric autonomous energy harvesting with natural advantages such as biocompatibility, flexibility, low cost, and easy fabrication. (C) 2014 AIP Publishing LLC
The stability for the Cauchy problem for elliptic equations
We discuss the ill-posed Cauchy problem for elliptic equations, which is
pervasive in inverse boundary value problems modeled by elliptic equations. We
provide essentially optimal stability results, in wide generality and under
substantially minimal assumptions. As a general scheme in our arguments, we
show that all such stability results can be derived by the use of a single
building brick, the three-spheres inequality.Comment: 57 pages, review articl
Протокол функционального обследования аноректальной зоны и классификация нарушений: международный консенсус и Российские рекомендации
This manuscript summarizes consensus reached by the International Anorectal Physiology Working Group (IAPWG) for the performance, terminology used, and interpretation of anorectal function testing including anorectal manometry (focused on high-resolution manometry), the rectal sensory test, and the balloon expulsion test. Based on these measurements, a classification system for disorders of anorectal function is proposed. Aim to provide information about methods of diagnosis and new classification of functional anorectal disorders to a wide range of specialists general practitioners, therapists, gastroenterologists, coloproctologists all who face the manifestations of these diseases in everyday practice and determine the diagnostic and therapeutic algorithm. Current paper provides agreed statements of IAPWG Consensus and comments (in italics) of Russian experts on real-world practice, mainly on methodology of examination. These comments in no way intended to detract from the provisions agreed by the international group of experts. We hope that these comments will help to improve the quality of examination based on the systematization of local experience with the use of the methods discussed and the results obtained. Key recommendations: the International Anorectal Physiology Working Group protocol for the performance of anorectal function testing recommends a standardized sequence of maneuvers to test rectoanal reflexes, anal tone and contractility, rectoanal coordination, and rectal sensation. Major findings not seen in healthy controls defined by the classification are as follows: rectoanal areflexia, anal hypotension and hypocontractility, rectal hyposensitivity, and hypersensitivity. Minor and inconclusive findings that can be present in health and require additional information prior to diagnosis include anal hypertension and dyssynergia
Regularity Properties and Pathologies of Position-Space Renormalization-Group Transformations
We reconsider the conceptual foundations of the renormalization-group (RG)
formalism, and prove some rigorous theorems on the regularity properties and
possible pathologies of the RG map. Regarding regularity, we show that the RG
map, defined on a suitable space of interactions (= formal Hamiltonians), is
always single-valued and Lipschitz continuous on its domain of definition. This
rules out a recently proposed scenario for the RG description of first-order
phase transitions. On the pathological side, we make rigorous some arguments of
Griffiths, Pearce and Israel, and prove in several cases that the renormalized
measure is not a Gibbs measure for any reasonable interaction. This means that
the RG map is ill-defined, and that the conventional RG description of
first-order phase transitions is not universally valid. For decimation or
Kadanoff transformations applied to the Ising model in dimension ,
these pathologies occur in a full neighborhood of the low-temperature part of the first-order
phase-transition surface. For block-averaging transformations applied to the
Ising model in dimension , the pathologies occur at low temperatures
for arbitrary magnetic-field strength. Pathologies may also occur in the
critical region for Ising models in dimension . We discuss in detail
the distinction between Gibbsian and non-Gibbsian measures, and give a rather
complete catalogue of the known examples. Finally, we discuss the heuristic and
numerical evidence on RG pathologies in the light of our rigorous theorems.Comment: 273 pages including 14 figures, Postscript, See also
ftp.scri.fsu.edu:hep-lat/papers/9210/9210032.ps.
Crk and CrkL adaptor proteins: networks for physiological and pathological signaling
The Crk adaptor proteins (Crk and CrkL) constitute an integral part of a network of essential signal transduction pathways in humans and other organisms that act as major convergence points in tyrosine kinase signaling. Crk proteins integrate signals from a wide variety of sources, including growth factors, extracellular matrix molecules, bacterial pathogens, and apoptotic cells. Mounting evidence indicates that dysregulation of Crk proteins is associated with human diseases, including cancer and susceptibility to pathogen infections. Recent structural work has identified new and unusual insights into the regulation of Crk proteins, providing a rationale for how Crk can sense diverse signals and produce a myriad of biological responses
Результаты современных радиационно-гигиенических обследований приграничных с Республикой Беларусь населенных пунктов Брянской области Российской Федерации. Часть 1: Характеристика населенных пунктов
This study presents results of radiation-hygienic surveys of the Bryansk Oblast settlements bordering the Republic of Belarus. The data were obtained in the course of implementation of measures of the “Program of joint activities of Russia and Belarus within the framework of the Union State for the protection of the population and rehabilitation of the territories affected by the Chernobyl NPP accident” in 2019–2022. The first part of the study presents a general characteristic of the current state of the problem of returning the residents of radioactively contaminated territories to normal living conditions and provides information on the settlements of the surveyed region. The modern demographic composition of the population is considered; the structure of private subsidiary plots is investigated. The results described in this part of the study indicate the main ways, which are relevant for the formation of the internal exposure dose of the public at the current stage of the radiation accident.В статье приводятся результаты радиационно-гигиенических обследований приграничных с Республикой Беларусь населенных пунктов Брянской области, полученные в 2019–2022 гг. в ходе реализации мероприятий «Программы совместной деятельности России и Беларуси в рамках Союзного государства по защите населения и реабилитации территорий, пострадавших в результате катастрофы на Чернобыльской АЭС». В первой части статьи дана общая характеристика современного состояния проблемы возвращения жителей радиоактивно загрязненных территорий к условиям нормальной жизнедеятельности и приводятся сведения о населенных пунктах обследованного региона. Рассмотрен современный демографический состав населения, исследована структура личных подсобных хозяйств. На основании результатов, описанных в данной части публикации, выделены основные пути формирования дозы внутреннего облучения населения, актуальные для современного этапа радиационной аварии
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