108 research outputs found

    Electromigration-Induced Flow of Islands and Voids on the Cu(001) Surface

    Full text link
    Electromigration-induced flow of islands and voids on the Cu(001) surface is studied at the atomic scale. The basic drift mechanisms are identified using a complete set of energy barriers for adatom hopping on the Cu(001) surface, combined with kinetic Monte Carlo simulations. The energy barriers are calculated by the embedded atom method, and parameterized using a simple model. The dependence of the flow on the temperature, the size of the clusters, and the strength of the applied field is obtained. For both islands and voids it is found that edge diffusion is the dominant mass-transport mechanism. The rate limiting steps are identified. For both islands and voids they involve detachment of atoms from corners into the adjacent edge. The energy barriers for these moves are found to be in good agreement with the activation energy for island/void drift obtained from Arrhenius analysis of the simulation results. The relevance of the results to other FCC(001) metal surfaces and their experimental implications are discussed.Comment: 9 pages, 13 ps figure

    Recombinant Analogs of Sea Anemone Kunitz-Type Peptides Influence P2X7 Receptor Activity in Neuro-2a Cells

    Get PDF
    Purinergic P2X7 receptors (P2X7) have now been proven to play an important role and represent an important therapeutic target in many pathological conditions including neurodegeneration. Here, we investigated the impact of peptides on purinergic signaling in Neuro-2a cells through the P2X7 subtype in in vitro models. We have found that a number of recombinant peptides, analogs of sea anemone Kunitz-type peptides, are able to influence the action of high concentrations of ATP and thereby reduce the toxic effects of ATP. The influx of calcium, as well as the fluorescent dye YO-PRO-1, was significantly suppressed by the studied peptides. Immunofluorescence experiments confirmed that the peptides reduce the P2X7 expression level in neuronal Neuro-2a cells. Two selected active peptides, HCRG1 and HCGS1.10, were found to specifically interact with the extracellular domain of P2X7 and formed stable complexes with the receptor in surface plasmon resonance experiments. The molecular docking approach allowed us to establish the putative binding sites of the most active HCRG1 peptide on the extracellular domain of the P2X7 homotrimer and propose a mechanism for regulating its function. Thus, our work demonstrates the ability of the Kunitz-type peptides to prevent neuronal death by affecting signaling through the P2X7 receptor.publishedVersio

    A clinical case of genetically confirmed myotubular myopathy

    Get PDF
    The aim of the study - presentation of a clinical case of genetically confirmed myotubular myopathy.Цель исследования – представление клинического случая генетически подтвержденной миотубулярной миопатии

    A Large Hadron Electron Collider at CERN

    Full text link
    This document provides a brief overview of the recently published report on the design of the Large Hadron Electron Collider (LHeC), which comprises its physics programme, accelerator physics, technology and main detector concepts. The LHeC exploits and develops challenging, though principally existing, accelerator and detector technologies. This summary is complemented by brief illustrations of some of the highlights of the physics programme, which relies on a vastly extended kinematic range, luminosity and unprecedented precision in deep inelastic scattering. Illustrations are provided regarding high precision QCD, new physics (Higgs, SUSY) and electron-ion physics. The LHeC is designed to run synchronously with the LHC in the twenties and to achieve an integrated luminosity of O(100) fb1^{-1}. It will become the cleanest high resolution microscope of mankind and will substantially extend as well as complement the investigation of the physics of the TeV energy scale, which has been enabled by the LHC

    Роль радионуклидной диагностики в комплексном обследовании ВИЧ-инфицированных пациентов с ишемической болезнью сердца

    Get PDF
    Cardiovascular disease is one of the most frequent cause of death globally. The greatest part is occupied by ischemic heart disease. HIV patients are composed to a higher risk of coronary heart disease.The purpose of this work is to evaluate the possibility of using molecular imaging methods in a comprehensive examination of patients with HIV infection and ischemic heart disease.Materials and methods. The survey group includes 32 patients with HIV infection. The comparison group consists of 25 age-matched patients with coronary heart disease and without HIV Infection. All patients were underwent myocardial perfusion scintigraphy using single photon emission computed tomography. Positron emission tomography with FDG were performed if necessary to assess the viability of the myocardium. The patients of the main group undergo diagnostic coronary angiography and standard set of laboratory and institutional diagnostic methods.Results. The results of which confirm the high efficiency of radionuclide diagnostic methods for detecting perfusion disorders, contractility and myocardial viability in patients with HIV infection even at an early stage. They can be recommended for using in a comprehensive examination of patients with HIV infection.Наиболее частой причиной смертности во всем мире являются сердечно-сосудистые заболевания, среди которых ведущее место занимает ишемическая болезнь сердца (ИБС). В группу с наиболее высоким риском развития ИБС входят пациенты с ВИЧ-инфекцией.Цель исследования: оценка возможности применения методов молекулярной визуализации в комплексном обследовании пациентов с ВИЧ-инфекцией и ИБС.Материал и методы. В группу обследования включено 32 пациента с ВИЧ-инфекцией, группу сравнения составили 25 сопоставимых по возрасту пациентов без ВИЧ-инфекции с ИБС. Всем пациентам проведена перфузионная сцинтиграфия миокарда (с помощью ОФЭКТ), ПЭТ/КТ сердца с ФДГ проводилась при необходимости оценки жизнеспособности миокарда в комплексе с диагностической коронароангиографией и стандартным набором лабораторно-инструментальных методов диагностики.Результаты. Полученные результаты подтверждают высокую эффективностью методов радионуклидной диагностики для выявления нарушений перфузии, сократимости и жизнеспособности миокарда у пациентов с ВИЧ-инфекцией даже на ранней стадии и могут быть рекомендованы к использованию в комплексном обследовании пациентов с ВИЧ-инфекцией
    corecore