Simple parameterization of nuclear attenuation data

Based on the nuclear attenuation data obtained by the HERMES experiment on nitrogen and krypton nuclei, it is shown that the nuclear attenuation $R_M^{h}$ can be parametrised in a form of a linear polynomial $P_1=a_{11}$ + $\tau a_{12}$, where $\tau$ is the formation time, which depends on the energy of the virtual photon $\nu$ and fraction of that energy $z$ carried by the final hadron. Three widely known parameterizations for $\tau$ were used for the performed fit. The fit parameters $a_{11}$ and $a_{12}$ do not depend on $\nu$ and $z$

Possible influence of the two string events on the hadron formation in a nuclear environment

One of the basic assumptions of the string model is that as a result of a DIS in nucleus a single string arises, which then breaks into hadrons. However the pomeron exchange considered in this work, leads to the production of two strings in the one event. The hadrons produced in these events have smaller formation lengths, than those with the same energy produced in the single string events. As a consequence, they undergo more substantial absorption in the nuclear matter

Nuclear Attenuation of high energy two-hadron system in the string model

Nuclear attenuation of the two-hadron system is considered in the string model. The two-scale model and its improved version with two different choices of constituent formation time and sets of parameters obtained earlier for the single hadron attenuation, are used to describe available experimental data for the $z$-dependence of subleading hadron, whereas satisfactory agreement with the experimental data has been observed. A model prediction for $\nu$-dependence of the nuclear attenuation of the two-hadron system is also presented.Comment: 8 page

Плевральный выпот при раке легкого

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New model for system of mesoscopic Josephson contacts

Quantum fluctuations of the phases of the order parameter in 2D arrays of mesoscopic Josephson junctions and their effect on the destruction of superconductivity in the system are investigated by means of a quantum-cosine model that is free of the incorrect application of the phase operator. The proposed model employs trigonometric phase operators and makes it possible to study arrays of small superconducting granules, pores filled with superfluid helium, or Josephson junctions in which the average number of particles $n_0$ (effective bosons, He atoms, and so on) is small, and the standard approach employing the phase operator and the particle number operator as conjugate ones is inapplicable. There is a large difference in the phase diagrams between arrays of macroscopic and mesoscopic objects for $n_0 < 5$ and $U<J$ ($U$ is the characteristic interaction energy of the particle per granule and $J$ is the Josephson coupling constant). Reentrant superconductivity phenomena are discussed.Comment: 4 pages, 3 Postscript figure

М. Г. ПРИВЕСУ 110 ЛЕТ

This article is devoted to the 110th anniversary of the honored scientist of the RSFSR, MD, professor Mikhail Grigorievich Prives. It represents the steps of his life and work, reflects his research areas: space anatomy, anatomy of people of different professions, x-Ray anatomy and experimental surgery.Статья посвящена 110-летию со дня рождения заслуженного деятеля науки РСФСР, доктора медицинских наук, профессора Михаила Григорьевича Привеса. Показаны этапы его жизни и деятельности, отражены созданные им научные направления - космическая анатомия, анатомия людей различных профессий, рентгеноанатомия, экспериментальная хирургия

АЛЬТЕРНАТИВНЫЙ МЕТОД ХИРУРГИЧЕСКОЙ КОРРЕКЦИИ РАССЛАИВАЮЩИХ АНЕВРИЗМ АОРТЫ В СОЧЕТАНИИ С АОРТАЛЬНОЙ НЕДОСТАТОЧНОСТЬЮ

Patients with dissecting aortic aneurysm and associated acute aortic insufficiency form a group of seriously ill patients with significant cardiac failure, generally involving other organs and systems. It justifies an attempt to reduce a surgical risk, by using more sparing procedures, including supracoronary replacement of the ascending aorta with its root reconstruction. The latter has been performed in 27 patients (mean 54,5 ± 2,1 years) with dissecting aortic aneurysm and aortic valvular insufficiency in 1996 to 2009. The major etiological factor was atherosclerosis (88%)/ Seventeen (63%), 6 (22,2%) and 4 (16%) had types I, IIA and II dissection, respectively. Overall hospital mortality was 11%. In late period, progressive aneurysm dissection needed reinterventions in 2 cases. The competence of the reconstructed aortic valve was satisfactory both just after surgery and throughout the follow-up. Indications for this option of chronic correction, surgical techniques, and immediate and long-term results are outlined. Пациенты с расслаивающей аневризмой аорты с сопутствующей аортальной недостаточностью состав- ляют группу тяжелых больных с выраженной сердечной недостаточностью и, как правило, заинтересо- ванностью других органов и систем. В связи с этим оправданным является стремление снизить риск опе- рации благодаря использованию более щадящих методик, в частности супракоронарного протезирования восходящей аорты с реконструкцией ее корня. Такого типа операции в ФНЦТиИО выполняют с 1996 года. За период с 1996-го по 2009 год 27 пациентам с расслаивающей аневризмой аорты и недостаточностью аортального клапана, средний возраст которых составил 54,5 ± 2,1 года, было выполнено супракоро- нарное протезирование аорты. Основным этиологическим фактором был атеросклероз – 89%. 17 (63%) пациентов имели I тип, 6 (22,2%) – IIA тип и 4 (14,8%) – II тип расслоения. Помимо супракоронарного протезирования аорты в 4 случаях потребовалось полное протезирование дуги аорты, в 13 – частичное. Общая госпитальная летальность составила 11%.

Beam-helicity asymmetries for single-hadron production in semi-inclusive deep-inelastic scattering from unpolarized hydrogen and deuterium targets

A measurement of beam-helicity asymmetries for single-hadron production in deep-inelastic scattering is presented. Data from the scattering of 27.6 GeV electrons and positrons off gaseous hydrogen and deuterium targets were collected by the HERMES experiment. The asymmetries are presented separately as a function of the Bjorken scaling variable, the hadron transverse momentum, and the fractional energy for charged pions and kaons as well as for protons and anti-protons. These asymmetries are also presented as a function of the three aforementioned kinematic variables simultaneously

Mechanism, dynamics, and biological existence of multistability in a large class of bursting neurons

Multistability, the coexistence of multiple attractors in a dynamical system, is explored in bursting nerve cells. A modeling study is performed to show that a large class of bursting systems, as defined by a shared topology when represented as dynamical systems, is inherently suited to support multistability. We derive the bifurcation structure and parametric trends leading to multistability in these systems. Evidence for the existence of multirhythmic behavior in neurons of the aquatic mollusc Aplysia californica that is consistent with our proposed mechanism is presented. Although these experimental results are preliminary, they indicate that single neurons may be capable of dynamically storing information for longer time scales than typically attributed to nonsynaptic mechanisms.Comment: 24 pages, 8 figure