Designing an Ab2-type alloy (TIZr-CrMNMO) for the hybrid hydrogen storage concept

The hybrid hydrogen storage method consists of the combination of both solid-state metal hydrides and gas hydrogen storage. This method is regarded as a promising trade-off solution between the already developed high-pressure storage reservoir, utilized in the automobile industry, and solid-state storage through the formation of metal hydrides. Therefore, it is possible to lower the hydrogen pressure and to increase the hydrogen volumetric density. In this work, we design a non-stoichiometric AB2 C14-Laves alloy composed of (Ti0.9Zr0.1)1.25Cr0.85Mn1.1Mo0.05. This alloy is synthesized by arc-melting, and the thermodynamic and kinetic behaviors are evaluated in a high-pressure Sieverts apparatus. Proper thermodynamic parameters are obtained in the range of temperature and pressure from 3 to 85 ◦C and from 15 to 500 bar: ∆Habs. = 22 ± 1 kJ/mol H2, ∆Sabs. = 107 ± 2 J/K mol H2, and ∆Hdes. = 24 ± 1 kJ/mol H2, ∆Sdes. = 110 ± 3 J/K mol H2. The addition of 10 wt.% of expanded natural graphite (ENG) allows the improvement of the heat transfer properties, showing a reversible capacity of about 1.5 wt.%, cycling stability and hydrogenation/dehydrogenation times between 25 to 70 s. The feasibility for the utilization of the designed material in a high-pressure tank is also evaluated, considering practical design parameters.Fil: Puszkiel, Julián Atilio. Helmholtz-zentrum Geesthacht; Alemania. Instituto de Investigaciones Energéticas de Cataluña; España. Comisión Nacional de Energía Atómica. Gerencia de Área de Aplicaciones de la Tecnología Nuclear. Gerencia de Investigación Aplicada CAB. Departamento Fisicoquímica de Materiales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Bellosta von Colbe, José M.. Helmholtz-zentrum Geesthacht; AlemaniaFil: Jepsen, Julian. Helmholtz-zentrum Geesthacht; Alemania. Helmut Schmidt University; AlemaniaFil: Mitrokhin, Sergey V.. Lomonosov Moscow State University; RusiaFil: Movlaev, Elshad. Lomonosov Moscow State University; RusiaFil: Verbetsky, Victor. Lomonosov Moscow State University; RusiaFil: Klassen, Thomas. Helmholtz-zentrum Geesthacht; Alemania. Helmut Schmidt University; Alemani

Trends in studying urban runoff: a retrospective analysis

The paper is a retrospective analysis of trends in quantitative empirical and theoretical studies of urban surface runoff from the mid-19th century to the early 90s of the 20th century, when the largest Soviet scientific school for such studies in the city of Kharkov was dissolved. As shown in the paper, the calculation methods for estimating peak discharges of urban surface runoff can be traced back to a pioneering work by T.J. Mulvaney (1850), which laid the foundation for the “rational method”. Later this method was developed in the works by E.Kuichling (1889) and D.E.Lloyd-Davies (1906

Impact of salt intake on inflammation markers in cardiovascular disease: a retrospective observational case-control study

Background. Salt intake currently poses a serious threat due to the cardiovascular challenge incurred by excessive sodium consumption.Objectives. The identification of markers associated with high salt intake in hypertensive patients.Methods. A retrospective observational case-control study surveyed 251 persons, including 194 hypertensive patients with stable salt intake. The intake was assessed in the “Charlton: SaltScreener” questionnaire. General, biochemical blood panels and interleukin levels (IL-1, IL-2, IL-4, IL-6, IL-8, IL-10, IL-18) were evaluated in the outcome of medical examination. Statistical data processing was performed with R using the RStudio software.Results. The mean patient age in survey was 72.47 ± 9.8 years, women prevailed in the selected cohort (n = 151, 60.1%). All patients were assigned in cohorts by the daily salt intake rate, ≤5 g (n = 12), 6–10 g (n = 144), >10 g salt per day (n = 38). The largest cohort (74.2%) united patients consuming 6–10 g salt per day, whereas only 6.2% patients consumed salt <5 g/day. Final analysis included patients consuming ≥6 g/day and having a C-reactive protein (CRP) level <20 mg/L. The analysis elicited an association between the monocyte count, CRP and salt intake towards the statement that higher salt intake leads to higher monocyte counts at CRP <20 mg/L in blood. Modelling revealed a close monocyte count–salt intake relationship, with a low-to-high intake transition sharply increasing the probability of elevated absolute monocyte count in blood provided the CRP level is <20 mg/L.Conclusion. The study infers a direct relationship between salt intake >10 g/day and blood monocyte count. However, its significance ceases at CRP rising to ≥20 mg/L

Синтез излучающей системы, формирующей секторную диаграмму направленности с минимизацией эффекта Гиббса

For the synthesis of radiating systems, which form the flat-topped radiation patterns there are some of the most convenient methods, including Fourier method, method of partial diagram and method of changing projections. These methods are handy for calculation, because they allow us to obtain the flat-topped radiation patterns with predetermined electrical characteristics. These are the following characteristics: side-lobe level, width of the main lobe of the radiation pattern, and amplitude of top ripple of the main lobe of the radiation pattern. Meeting the challenge of synthesizing flat-topped radiation pattern is complicated by the break points available in a predetermined radiation pattern, which prevent the convergence of the Fourier series. The points of discontinuity, in turn, lead to the emergence of extremes that are associated with the Gibb’s phenomenon. To eliminate them, are used different methods for approximating a given radiation pattern (a series of Kotelnikov polynomial and that of Chebyshev). Such approximation, in turn, imposes restrictions on the basic quality indicators the flat-topped radiation patterns, such as the steepness of fronts and top ripple of the main lobe of the radiation pattern. The proposed method provides the lowest side-lobe level with small amplitude of top ripple of the main lobe of the flat-topped radiation pattern. The paper offers a linear approximation option of the given radiation pattern, which allows a synthesized radiation pattern with a diversity of quality parameters. This is achieved by linear approximation coefficients that can be determined using optimization algorithms. Depending on the target function for the optimization algorithm it is possible to determine the best trade-off between making the steepness parameter of the fronts and the top ripple amplitude of the main lobe of the flat-topped radiation pattern. The important feature of the method is that it minimizes the Gibbs phenomenon and is easy to calculate gratings with the small number of radiators.Для синтеза излучающих систем, формирующих секторные диаграммы направленности, существуют несколько наиболее удобных методов, среди которых: метод Фурье, метод парциальных диаграмм и метод изменяющихся проекций. Данные методы удобны для расчета, потому что позволяют получить секторные диаграммы направленности с заданными электрическими характеристиками. Этими характеристиками являются: уровень боковых лепестков, ширина главного лепестка диаграммы направленности и амплитуда переколебаний вершины главного лепестка секторной диаграммы направленности.   Решение задачи синтеза секторной диаграммы направленности осложняется наличием точек разрыва в заданной диаграмме направленности, которые препятствуют сходимости ряда Фурье. Точки разрыва, в свою очередь, приводят к возникновению экстремумов, которые связаны с эффектом Гиббса. Для их устранения применяют различные методы аппроксимации заданной диаграммы направленности (полиномами рядов Котельникова, Чебышева). Подобные аппроксимации накладывают ограничения на основные качественные показатели секторных диаграмм направленности, такие как: крутизну фронтов и переколебания вершины главного лепестка диаграммы направленности. Предложенный метод позволяет получить наименьший уровень боковых лепестков при незначительном переколебании плоской вершины главного лепестка секторной диаграммы направленности. Предложен вариант линейной аппроксимации заданной диаграммы направленности, который позволяет получать синтезированные диаграммы направленности с разного рода параметрами качества. Это достигается с помощью коэффициентов линейной аппроксимации, которые могут быть определены с помощью алгоритмов оптимизации. В зависимости от выбранной целевой функции для алгоритма оптимизации появляется возможность определения наилучших решений компромисса между параметром крутизны фронтов и амплитудой переколебаний вершины главного лепестка секторной диаграммы направленности. Важными особенностями данного метода является то, что он позволяет минимизировать эффект Гиббса и удобен для расчета решеток с малым числом излучателей

Subsurface disorder and electro-optical properties of proton-exchanged LiNbO3 waveguides produced by different techniques

It has been established, that proton-exchanged LiNbO3 waveguides have a marked subsurface layer with structural disorder inducing degradation of electro-optical properties of these waveguides. At the same time, such a subsurface disorder is found to be less pronounced in soft proton-exchanged (SPE) waveguides in comparison with annealed proton-exchanged (APE) ones. The experimental samples of phase modulators fabricated by SPE technique exhibit a better electro-optical efficiency compared to the LiNbO3 modulators produced by the standard and improved APE techniques

Госпитальная инфекция в онкоурологии

Hospital-acquired (nosocomial, intrahospital) infections are a principal cause of severe complications and death in cancer diseases in the postoperative period. A current infection-controlling system that notifies all cases of nosocomial infections in the patients of the hospital, including those with urinary tract cancer, has been in existence in Moscow City Cancer Hospital Sixty-Two since 2001. The paper presents the data of the authors' own follow-ups (in 2005—2006), which reflect the incidence of postoperative nosocomial urinary tract infections (PNUTI) in urological cancer patients depending on the site of a tumor, the scope of surgical intervention, the etiological agents of PNUTI, and their susceptibility to antibiotics. By using the results of the study, the authors have developed and proposed algorithms of efficient antibiotic therapy for PNUTI in patients with cancer of the kidney, urinary bladder, and prostate.

The predictive value of various indicators of sperm for male fertility

Introduction. DNA fragmentation of sperm is one of the possible causes of reduced fertility potential of men. However, a significant correlation between conventional semen parameters and sperm DNA fragmentation was not found. This fact determines the relevance of the study of the influence of various parameters of sperm on male fertility.Materials and methods. The study included 60 men, aged 26–36 years (median – 30 years) with idiopathic infertility and the level of DNA fragmentation of sperm is higher than 15 %. These men were treated with hyperbaric oxygen therapy, after 3 months in vitro fertilization performed partners of these men. DNA fragmentation of sperm cells was determined by TUNEL (upper limit of normal – 15 %). The level of reactive oxygen species (ROS) of the ejaculate were determined by chemiluminescence (upper limit of normal – 0.64 mV/s).Results. The frequency of pregnancy in vitro fertilization was following: 62.8 and 64.7 % (p > 0.05) for the total number sperm of spermatozoa < 38 × 106 /ejaculate and ≥ 39 × 106 /ejaculate, respectively; 63.3 and 63.6 % (p > 0.05) for mobility (a + b) of spermatozoa < 40 and ≥ 40 %, respectively; 58.3 and 64.6 % (p > 0.05) for normal forms of spermatozoa < 4 and ≥ 4 %, respectively; 67.3 and 20.0 % (p < 0.05) for the level of DNA fragmentation of sperm ≤ 15 and > 15 %, respectively; 64.9 and 33.3 % (p < 0.05) for the level of ROS in semen ≤ 0.64 and > 0.64 mV/s, respectively.Conclusion. The probability of pregnancy after in vitro fertilization significantly depends on the levels of sperm DNA fragmentation in the sperm and level of ROS in semen

Выявление избыточного количества натрия в миокарде в условиях натриевой нагрузки с помощью двухэнергетической компьютерной томографии

Introduction. The direct relationship between the level of sodium intake, arterial hypertension, followed by the development of heart failure, a hypothesis of the direct influence of excessive sodium accumulation in myocardial glycosaminoglycans seems quite probable, which can further contribute to the occurrence of diastolic dysfunction and heart failure.The aim of the study was to identify excess sodium in rats under conditions of sodium loading, in comparison with rats at a normal level of sodium intake. Materials and methods. Ten male Wistar rats with the same body weight were divided into two groups: the excess salt intake group and the normal salt intake group. Estimation of the amount of Na and NaCl in the animal myocardium was performed using dual energy computed tomography (DECT) samples. Samples were scanned on a Revolution GSI tomograph (GE Healthcare). For statistical processing of the obtained data, the R language was used. Results. The results of the study showed that the accumulation of Na and NaCl does not depend on the average level of animal feed intake, there is no correlation between weight and accumulation of excess Na in tissues, the level of Na and NaCl detected in myocardial tissue significantly increases the likelihood of a high salt diet in rats, and a relationship between the content Na in the myocardium and NaCl+H2O. Conclusion. The experiment confirmed the existence of a reliable relationship between the sodium compounds calculated on the basis of DECT and the content of these compounds in the samples. The small number of samples did not allow us to calculate normalized rats, but we noted a clear difference between the control group and the high sodium diet.Введение. Учитывая прямую взаимосвязь между уровнем потребления натрия (Na), артериальной гипертензией с последующим развитием сердечной недостаточности, достаточно вероятным представляется гипотеза непосредственного влияния избыточного накопления Naвгликозаминогликанах миокарда, что в дальнейшем может способствовать возникновению диастолической дисфункции и сердечной недостаточности. Цель исследования: выявление избыточного количества натрия у крыс, находящихся в условиях натриевой нагрузки, в сравнении с крысами, находящимися на нормальном уровне потребления натрия. Материалы и методы. Десять самцов крыс рода Wistar с одинаковой массой тела были разделены на две группы: группа избыточного потребления соли и группа нормального потребления соли. Оценка количества натрия и NaCl в миокарде животных была выполнена при двухэнергетической компьютерной томографии (ДЭКТ) образцов. Сканирование образцов выполняли на томографе RevolutionGSI (GEHealthcare). Для статистической обработки полученных данных использовали язык R. Результаты исследования показали: накопление натрия и NaCl, не зависит от среднего уровня потребления корма животным, отсутствует корреляция между весом и уровнем накопления избытка натрия в тканях, уровень натрия и NaCl в ткани миокарда значимо повышают вероятность высокосолевой диеты у крысы, выявлена зависимость между содержанием натрия в миокарде и NaCl+Н2О. Заключение. Эксперимент подтвердил наличие достоверной связи вычисленных на основании ДЭКТ значений соединений натрия с содержанием этих соединений в образцах. Малое количество образцов не позволило нам рассчитать нормализованные показатели для крыс, однако мы отметили четкое различие между контрольной группой и группой с высоким содержанием натрия в диете