6 research outputs found

    Spallative ablation of dielectrics by X-ray laser

    Full text link
    Short laser pulse in wide range of wavelengths, from infrared to X-ray, disturbs electron-ion equilibrium and rises pressure in a heated layer. The case where pulse duration τL\tau_L is shorter than acoustic relaxation time tst_s is considered in the paper. It is shown that this short pulse may cause thermomechanical phenomena such as spallative ablation regardless to wavelength. While the physics of electron-ion relaxation on wavelength and various electron spectra of substances: there are spectra with an energy gap in semiconductors and dielectrics opposed to gapless continuous spectra in metals. The paper describes entire sequence of thermomechanical processes from expansion, nucleation, foaming, and nanostructuring to spallation with particular attention to spallation by X-ray pulse

    Recent Advances in Understanding Particle Acceleration Processes in Solar Flares

    Full text link
    We review basic theoretical concepts in particle acceleration, with particular emphasis on processes likely to occur in regions of magnetic reconnection. Several new developments are discussed, including detailed studies of reconnection in three-dimensional magnetic field configurations (e.g., current sheets, collapsing traps, separatrix regions) and stochastic acceleration in a turbulent environment. Fluid, test-particle, and particle-in-cell approaches are used and results compared. While these studies show considerable promise in accounting for the various observational manifestations of solar flares, they are limited by a number of factors, mostly relating to available computational power. Not the least of these issues is the need to explicitly incorporate the electrodynamic feedback of the accelerated particles themselves on the environment in which they are accelerated. A brief prognosis for future advancement is offered.Comment: This is a chapter in a monograph on the physics of solar flares, inspired by RHESSI observations. The individual articles are to appear in Space Science Reviews (2011

    Организация рабочих процессов по рекрутингу доноров и заготовке реконвалесцентной плазмы в период пандемии COVID-19

    No full text
    Background. The pandemic of the new coronavirus infection has challenged the medical community for quickly finding and implementing effective methods of treatment. In the absence of a vaccine or specific therapy with proven effectiveness, the usage of convalescent plasma can be the one of perspective methods. An important aspect of this technology is the efficient and safe preparation of convalescent plasma. To date, in the world literature there are practically no publications about donor recruitment and the specifics of the preparation of convalescent plasma. Purpose of the research. Presentation of the experience of organizing a workflow for recruiting donors and stockpiling of convalescent plasma with a high titer of virus-neutralizing antibodies to SARS-CoV-2. Methods. The analysis of the work of the Blood Service of the Moscow Department of Health for stockpiling of COVID-19 convalescent plasma has been executed. In total it has been stockpiled 1240 doses. The normative documentation has been developed by a working group on the basis of the current federal legislation of Russian federation and been approved by the Moscow Department of Health. The titer of neutralizing antibodies (VNA) has been determined as the basic method for assessing the immunological viability of convalescent plasma. The main characteristics of donors, the characteristics of the disease course, the results of preliminary testing for the presence of specific antibodies by ELISA and CLIA methods has been compared with VNA titers in the stockpiled convalescent plasma. Results. Due to a Moscow Health Departments order No. 325 dated 01.04.2020 (a basic local regulatory document) it has been developed a regulation for the stockpiling, examination, storage, safety and transfering of fresh frozen pathogen-reduced plasma of COVID-19 convalescent donors to medical organizations of the Moscow Health Department. For arranging an interaction with donors it has been created a call-center. For effective preliminary selection, it has been formed a donor characteristics list, which has been combined with screening of specific antibodies by ELISA and CLIA methods. Conclusions. Developed a system of recruiting donors and procurement process of convalescent plasma for treatment СOVID-19, which includes the necessary regulations, algorithms for the selection and recruitment of donors, the registry of donors and recipients, algorithms, efficiency and safety of convalescent plasma.Обоснование. Пандемия новой коронавирусной инфекции поставила перед медицинским сообществом задачу быстрого поиска и внедрения эффективных методик лечения. В условиях отсутствия вакцины и средств специфической терапии с доказанной эффективностью в качестве одной из перспективных методик рассматривается трансфузия реконвалесцентной плазмы (РП). Важным аспектом данной технологии является заготовка эффективного и безопасного компонента. На сегодняшний день публикации по рекрутингу доноров и особенностях заготовки РП в мировой литературе практически отсутствуют. Цель исследования Анализ опыта организации рабочего процесса по привлечению доноров и заготовке РП с высоким титром вируснейтрализующих антител к SARS-CoV-2. Методы. Проведен анализ работы Службы крови Департамента здравоохранения г. Москвы (ДЗМ) по заготовке РП COVID-19. Всего заготовлено 1240 доз. Нормативная документация разработана рабочей группой на основании действующего федерального законодательства и утверждена ДЗМ. Как базовая методика оценки иммунологической состоятельности РП, определен титр вируснейтрализующих антител (ВНА). Проведено сопоставление основных характеристик доноров, особенностей течения заболевания, результатов предварительного тестирования на наличие специфических антител методами ИФА и ИХЛА с титрами ВНА заготовленной РП. Результаты. Работа по заготовке, обследованию, хранению, обеспечению безопасности и передаче в медицинские организации ДМЗ свежезамороженной патогенредуцированной плазмы доноров-реконвалесцентов COVID-19 была организована на основании приказа ДЗМ от 01.04.2020 № 325 как базового локального нормативного документа. Для оптимальной коммуникации с состоявшимися донорами и привлечения реконвалесцентов использовались ресурсы колл-центра. Для эффективного предварительного отбора доноров применялись анализ характеристик донора (плазма с наибольшими значениями титра ВНА ожидаема от доноров-мужчин, переболевших с признаками явной вирусной пневмонии) и результаты скрининга специфических антител методами ИФА и ИХЛА. Заключение. Разработана система обеспечения рекрутинга доноров и процесса заготовки РП для лечения СOVID-19, включающая необходимые нормативные документы, алгоритмы отбора и привлечения доноров, реестр доноров и реципиентов, алгоритмы обеспечения эффективности и безопасности РП

    Recent Advances in Understanding Particle Acceleration Processes in Solar Flares

    No full text
    corecore