Theory of high harmonic generation in relativistic laser interaction with overdense plasma

High harmonic generation due to the interaction of a short ultra relativistic laser pulse with overdense plasma is studied analytically and numerically. On the basis of the ultra relativistic similarity theory we show that the high harmonic spectrum is universal, i.e. it does not depend on the interaction details. The spectrum includes the power law part $I_n\propto n^{-8/3}$ for $n<\sqrt{8\alpha}\gamma_{\max}^3$, followed by exponential decay. Here $\gamma_{\max}$ is the largest relativistic $\gamma$-factor of the plasma surface and $\alpha$ is the second derivative of the surface velocity at this moment. The high harmonic cutoff at $\propto \gamma_{\max}^3$ is parametrically larger than the $4 \gamma_{\max}^2$ predicted by the ``oscillating mirror'' model based on the Doppler effect. The cornerstone of our theory is the new physical phenomenon: spikes in the relativistic $\gamma$-factor of the plasma surface. These spikes define the high harmonic spectrum and lead to attosecond pulses in the reflected radiation.Comment: 12 pages, 9 figure

Some aspects of teaching medical informatics at medical universities

В статті розглядаються питання сучасного викладання медичної інформатики студентам медичних університетів. В роботі описано основну мету дисципліни, пропонуються шляхи вдосконалення її. Актуальність даної тематики підтверджує те, що наукові методи та інструментальні засоби все більш широко проникають в будь-які галузі життєдіяльності людини, і медицина не є виключенням, Саме це надає медичній інформатиці характер міждисциплінарної галузі, яка набуває все більш важливе загальнонаукове і загальноосвітнє значення. Розкрито важливе питання забезпечення формування у сучасного лікаря цілісного системного наукового світогляду на проблеми інформатизації охорони здоров'я. Дана стаття буде цікава викладачам закладів вищої медичної освіти.The article discusses the issues of up-to-date teaching medical informatics to students of medical universities. The paper describes the main goal of the discipline, suggests ways to improve it. The relevance of this topic lies in the fact that scientific methods and tools are increasingly penetrating into any branch of human life, and medicine is not an exception. That is why Medical Informatics belongs to interdisciplinary field, and acquires important scientific and educational value. Authors disclosed the important issue of the formation of a holistic and scientific worldview in modern doctors on the problems of health care informatization. This article would be interesting to teachers of higher educational institutions of a medical profile

Development of thyroid pathology in medical workers with chronic exposure to low doses ionizing radiation

Introduction. The literature review deals with the effects of ionizing radiation and radiation on the body of medical personnelВведение. Рассмотрены вопросы воздействия ионизирующего излучения и радиации на организм медицинского персонала

The Bubble regime of laser-plasma acceleration: monoenergetic electrons and the scalability

The Bubble regime of electron acceleration in ultra-relativistic laser plasma is considered. It has been shown that the bubble can produce ultra-short dense bunches of electrons with quasi-monoenergetic energy spectra. The first experiment in this regime done at LOA has confirmed the peaked electron spectrum (J. Faure, et al., {\it submitted}, 2004). The generated electron bunch may have density an order of magnitude higher than that of the background plasma. The bubble is able to guide the laser pulse over many Rayleigh lengths, thus no preformed plasma channel is needed for high-energy particle acceleration in the bubble regime. In the present work we discuss a simple analytical model for the bubble fields as well as the scaling laws.Comment: accepted for publication in Plasma Physics and Controlled Fusion, 200

Construction of nutrient media for L-form brucella

Dry nutrient media on the basis of hepatic infusion and Siberian roach hydrolyzate are constructed. Experimental data demonstrate that these media possess high sensitivity, completely inhibit growth of S-form Brucella, do not require рН adjustment, filtration and autoclaving. They can be used for isolation, cultivation and accumulation of L-form Brucella for bacteriological diagnostics of brucellosis. As these media are accessible for transportation, they are applicable for stationary and field conditions

One-dimensional steady-state structures at relativistic interaction of laser radiation with overdense plasma for finite electron temperature

One-dimensional steady-state plasma-field structures in overdense plasma are studied assuming that the electron temperature is uniform over plasma bulk and the ions are stationary. It is shown that there may exist solutions for electron distributions with cavitation regions in plasma under the action of ponderomotive forceComment: 6 pages, 4 figure

Comparison of proton channel, phagocyte oxidase, and respiratory burst levels between human eosinophil and neutrophil granulocytes.

Robust production of reactive oxygen species (ROS) by phagocyte NADPH oxidase (phox) during the respiratory burst (RB) is a characteristic feature of eosinophil and neutrophil granulocytes. In these cells the voltage-gated proton channel (Hv1) is now considered as an ancillary subunit of the phox needed for intense ROS production. Multiple sources reported that the expression of phox subunits and RB is more intensive in eosinophils than in neutrophils. In most of these studies the eosinophils were not isolated from healthy individuals, and a comparative analysis of Hv1 expression had never been carried out. We performed a systematic comparison of the levels of essential phox subunits, Hv1 expression and ROS producing capacity between eosinophils and neutrophils of healthy individuals. The expression of phox components was similar, whereas the amount of Hv1 was approximately 10-fold greater in eosinophils. Furthermore, Hv1 expression correlated with Nox2 expression only in eosinophils. Additionally, in confocal microscopy experiments co-accumulation of Hv1 and Nox2 at the cell periphery was observed in resting eosinophils but not in neutrophils. While phorbol-12-myristate-13-acetate-induced peak extracellular ROS release was approximately 1.7-fold greater in eosinophils, oxygen consumption studies indicated that the maximal intensity of the RB is only approximately 1.4-fold greater in eosinophils. Our data reinforce that eosinophils, unlike neutrophils, generate ROS predominantly extracellularly. In contrast to previous works we have found that the two granulocyte types display very similar phox subunit expression and RB capacity. The large difference in Hv1 expression suggests that its support to intense ROS production is more important at the cell surface

Туляремия в Архангельской области: клинико-эпидемиологическая характеристика

Aim: to analyze epidemiological and clinical features of tularemia cases diagnosed between 2010 and 2014 and to identify factors associated with complications.Methods: We conducted retrospective cohort study including all patients hospitalized with tularemia between 2010 and 2014.Results: Most of tularemia cases were diagnosed in July (20,8%) and August (57,1%) among adult females (63,6%). The most common forms were bubonic and ulcer-bubonic (89,6%). Buboes were commonly found in the upper femoral and groin regions (92,2%). Diagnostic errors were revealed in 54,1% of cases. The most frequent misdiagnoses were lymphadenitis and fever of unknown origin. Delay in effective antibiotic therapy was associated with an increased rate of complications.Conclusion: Tularemia has a diversity of clinical presentations. Doctors need to memorize the most common clinical signs of tularemia (fever and lymphadenitis) to make timely diagnosis.Цель: представить клинико-эпидемиологическую характеристику туляремии у пациентов, госпитализированных в инфекционный стационар и проанализировать возможные причины негладкого течения инфекции.Материалы и методы: проведено ретроспективное когортное исследование с включением всех пациентов с туляремией, госпитализированных в период с 2010 по 2014 г. в центр инфекционных болезней Архангельской областной клинической больницы.Результаты: среди заболевших преобладали взрослые, преимущественно лица женского пола (63,6%). Чаще всего инфекция регистрировалась в июле (20,8%) и августе (57,1%). В структуре клинических форм 89,6% занимали бубонная и язвенно-бубонная формы с локализацией бубонов в паховой и бедренной областях (92,2%). Частота диагностических ошибок догоспитального этапа составила 54,1%. Наиболее частыми диагнозами были лимфаденит и лихорадка неясного генеза. Позднее назначение антибактериальной терапии явилось фактором, способствующим негладкому течению заболевания.Заключение: несмотря на многообразие клинических проявлений туляремии, для своевременной диагностики инфекции врачу необходимо помнить о наиболее манифестных симптомах болезни, которыми являются лихорадка и лимфаденит

РОЛЬ ЭНТЕРОВИРУСА ECHO 30 В ЭТИОЛОГИИ ЭНТЕРОВИРУСНОЙ ИНФЕКЦИИ НА СЕВЕРО -ЗАПАДЕ РОССИИ В 2013 г

In 2013 after two previous years when the situation had been calm the incidence rates of enterovirus infection significantly increased on certain territories of the North-West of Russia. In Novgorod and Vologda regions and in Saint-Petersburg enterovirus meningitis group cases were registered. The etiology of enterovirus infection was studied by virological and molecular methods. Enterovirus ECHO30 was identified as the principal etiological agent of the cases. Molecular study revealed that enteroviruses ECHO30 isolated in the North-West of Russia belonged to the genotype H and formed two subtypes inside this genotype. Phylogenetic analysis has shown that enteroviruses ECHO30 of both subtypes were closely related to the strains detected in different provinces of China in 2010-2013. Probably enteroviruses ECHO30 of the genotype H which largely circulated in Russia in 2013 and practically had not been detected in the country earlier had been imported on the territory of Russia from South-East Asia. Enteroviruses ECHO30 isolated in  Arkhangelsk and Novgorod regions in 2008-2009 belonged to another genotype Ec2. Enteroviruses of this genotype had circulated at that time in the European countries.В 2013 г. после относительно спокойной ситуации в течение двух предыдущих лет заболеваемость энтеровирусной инфекцией на ряде территорий Северо-Западного федерального округа резко возросла. Были зарегистрированы групповые заболевания энтеровирусным менингитом в Новгородской, Вологодской областях и в Санкт-Петербурге. Проведена расшифровка этиологии заболеваний энтеровирусной инфекцией с использованием вирусологического и молекулярно- генетического методов исследования. В качестве основного этиологического агента был идентифицирован энтеровирус ЕСНО 30. Установлено, что изолированные на Северо-Западе России вирусы ЕСНО 30 относились к генотипу Н и сформировали две филогенетические группы. Филогенетический анализ показал, что энтеровирусы ЕСНО 30 обоих субтипов были наиболее близко родственны штаммам, выделенным в разных провинциях Китая в 2010–2013 гг. Вероятно, энтеровирусы ЕСНО 30 генотипа Н, которые широко циркулировали в России в 2013 г. и ранее практически не выявлялись в стране, были импортированы на территорию России из Юго-Восточной Азии. Энтеровирусы ЕСНО 30, изолированные в 2008–2009 гг. в Архангельской и Новгородской областях, относились к другому генотипу Ес2, энтеровирусы этого генотипа циркулировали в тот период в странах Европы