ПРОФИЛЬ ОБШИВКИ И ЦИКЛЫ ВИБРОНАГРУЖЕНИЯ ПОЛУВАГОНА

The design of the side walls of freight gondola cars, designed for the use of vibration loading technology assume their sheathing with sheet profiles. Earlier held survey of technical state of gondola cars with a body height of 2365 mm, delivered for unloading and cleaning of cargo residues using vibration equipment [3] revealed an increased damageability of elements of the side walls. About 90% of gondola cars had separations of siding sheets from the side wall pillars and cracks of up to 200 mm in the corners of middle and upper corrugations of the first and second panels. This led to the fact that a new edition of GOST 22235, in force since 2010, prohibits the delivery of cars with body height of 2365 mm for unloading using vibration technology. To increase the operational reliability of such complexes, different designs, models are offered, new calculations and experiments are conducted. The article presents the results of authors’ research, conducted primarily with simulation and hybrid modeling methods, its conclusions and options of alternative sheathing profiles, tested in Yekaterinburg, showing the possibility of using overhead vibration machines for unloading gondola-cars with a height of the body of 2365 mm and with account of permissible time of operation of the rolling stock.Конструкции боковых стен грузовых полувагонов, рассчитанных на использование технологий виброразгрузки, предполагают их обшивку листовыми профилями. Чтобы повысить эксплуатационную надежность таких комплексов, предлагаются разные конструктивные решения, модели, проводятся все новые расчеты и эксперименты. В числе прочих в статье представлены авторские исследования и прошедшие в Екатеринбурге проверку варианты альтернативных профилей обшивки, показавших возможность применения накладных вибромашин на разгрузке полувагонов с высотой кузова 2365 мм и с учетом предельно допустимого времени эксплуатации подвижного состава

Nonlinear excitation of kinetic Alfven waves and whistler waves by electron beam-driven Langmuir waves in the solar corona

© ESO 2003We study a new nonlinear excitation mechanism of kinetic Alfvén waves (KAWs) and whistler waves (Ws) by electron beam-driven Langmuir waves (Ls). The generation conditions for the parametric decay instability L W + KAW are determined and the growth rate is calculated. We show that the resonant pairs of KAWs and whistler waves are nonlinearly coupled to the pump Langmuir waves and their amplitudes undergo exponential growth from the thermal level. The perpendicular dispersion of KAWs strongly increases the coupling due to the nonlinear current parallel to the ambient magnetic field. Our study suggests that the nonlinear coupling of Langmuir wave energy into KAWs and whistlers can provide an efficient sink for weakly dispersive Langmuir waves excited by fast electron beams in the solar corona when the electron plasma frequency is lower than the electron gyrofrequency. This condition can be satisfied in the low-density magnetic filaments that are rooted in the depleted patches at the coronal base and extend to the high corona. At the same time, the Langmuir-driven KAWs and whistlers give rise to scattering and/or thin structures of radio emission penetrating through, or generated in these regions. Since the decay into sunward propagating KAWs is strongest, the nonlinearly driven KAWs can be easily distinguished from the waves generated at the coronal base and propagating away from the Sun. Our results may be used in the analysis of solar radio data and for remote probing of the coronal plasma, magnetic fields, and waves.Yu. Voitenko, M. Goossens, O. Sirenko and A. C.-L. Chia

Surface Tension of Seawater

New measurements and a reference correlation for the surface tension of seawater at atmospheric pressure are presented in this paper. Surface tension of seawater was measured across a salinity range of 20 ⩽ S ⩽ 131 g/kg and a temperature range of 1 ⩽ t ⩽ 92 °C at atmospheric pressure using the Wilhelmy plate method. The uncertainty within measurements varied from 0.18 to 0.37 mN/m with the average uncertainty being 0.22 mN/m. The experimental procedures were validated with tests conducted on ACS reagent grade water and aqueous sodium chloride solutions. Literature data and present measurements were evaluated and a reference correlation was developed expressing surface tension of seawater as a function of temperature and salinity. The average absolute percentage deviation between measurements and the correlation was 0.19% while the maximum deviation was 0.60%.Center for Clean Water and Clean Energy at MIT and KFUPM (Project R13-CW-10

A contemporary view of the problem of newly diagnosed chronic hepatitis in children

The article presents the results of a retrospective study of case histories of children with a first established diagnosis of chronic hepatitis. Based on the results of the study, we determined the etiological structure, clinical picture, and features of the epidemiology of chronic hepatitis.В статье представлены результаты ретроспективного исследования историй болезни детей с впервые установленным диагнозом хронического гепатита. По результатам обследования определена этиологическая структура и клиническая картина гепатитов, особенности эпидемиологи

Determination of ππ\pi\pi scattering lengths from measurement of π+π−\pi^+\pi^- atom lifetime

The DIRAC experiment at CERN has achieved a sizeable production of $\pi^+\pi^-$ atoms and has significantly improved the precision on its lifetime determination. From a sample of 21227 atomic pairs, a 4% measurement of the S-wave $\pi\pi$ scattering length difference $|a_0-a_2| = (.0.2533^{+0.0080}_{-0.0078}|_\mathrm{stat}.{}^{+0.0078}_{-0.0073}|_\mathrm{syst})M_{\pi^+}^{-1}$ has been attained, providing an important test of Chiral Perturbation Theory.Comment: 6 pages, 6 figure

Influence of sodium desoxyribonucleate on anti-infectious protection and hematopoiesis in patients with polytrauma (randomized prospective, double-blind, placebo-controlled study)

The  aim of the study was to evaluate  the effect of sodium  deoxyribonucleate on anti-infectious resistance and hematopoiesis in patients with polytraumas. A single-center study of sodium  deoxyribonucleate effectiveness approved by the local Ethics Committee (protocol No. 4 05/18/2016), was conducted in 54 patients with polytrauma. The  main  group  included 27 people, at the mean  age of 39 (29-51)  years old; ISS severity score,  26 (22-34). The  comparison group  comprised 27 people, mean  age,  40 years old (26-53), mean  ISS severity score was 25 points (20 to 29). The patients with randomly attributed even numbers were injected with 5 ml preparation from vials of even-numbered series, the patients with odd numbers were treated with preparation from the odd-numbered series. They were injected intramuscularly daily from day 1 to day 10 after the injury. Before treatment, as well as on days 8, 15 after injury, peripheral blood was examined for leukocyte, erythrocyte counts, hemoglobin, total  protein, blood  IL-6, CRP; proportion of CD117+  and  CD34+  mononuclear cells, CD14+ monocytes, CD14+ granulocytes, HLA-DR+  mononuclear cells, defensin + granulocytes.On  the  day  +8,   patients from  the  main  group,  against  the  comparison group  showed  an  increase   in lymphocytes, monocytes, CD117+ and CD34+ cell counts. Serum IL-6 and CRP were decreased in both groups of the patients to a similar  degree. Terms  of hospitalization in the main  group were 32.8 days, against  39.6 in comparison group. The number of complications per 1 case was, respectively, 21 versus 39, thus being 1.8 times less than  in comparison group.  When developing complications, anemia (Hb  < 90 g/l),  or hypoproteinaemia (< 60 g/l) in the main group was, respectively, 2.5and 3.5-fold  less than  in the comparison group.Treatment with sodium  deoxyribonucleate in polytrauma may promote migration of blood precursors to the bloodstream, increase anti-infectious properties of leukocytes, reduce duration of anemia and hypoproteinemia, number of complications and decrease the terms of hospitalization

Magnetic resonance spectroscopy of hippocampal and striatal neurometabolites in experimental PTSD rat modeling

The spectrum of the metabolites in the dorsal region of the hippocampus and striatum was studied using the method of 1H magnetic resonance spectroscopy at experimental modeling of the posttraumatic stress disorder syndrome (PTSD) in rats. PTSD was reproduced by exposure of the cat cue to rats daily along 10 day by 10 minutes at once. The anxiety level of animals was estimated 12 days later after the end of the experimental series of stress. Based on the anxiety index, the rats were divided into 3 phenotypes. The animals with an anxiety index > 0.8 (group 1) had lower plasma corticosterone compared with rats form the control group. In animals with an anxiety index in the range 0.7–0.8 (group 2), an elevated corticosterone level was noted. The rats with an anxiety index < 0.7 (group 3) had a lower plasma corticosterone level compared with animals from the control group. Rats of group 2 were characterized by an increased level of GABA in the hippocampus compared with controls. In the remaining groups, the percentages of GABA in the hippocampus and striatum did not differ significantly from the control. The distribution of NAA differed form that of GABA. The highest level of NAA was found in the striatum for rats from group 1, whereas NAA in animals form groups 1 or 3 did not differ from the control. The NAA level in the hippocampus was similar between all groups, including the control. The results obtained indicate that multiple exposures to psychological stress associated with the sense of proximity of a natural enemy in some animals cause an anxiolytic reaction. These animals are characterized by a stable corticosterone level and a stable level of neurometabolites in the studied structures of the brain. For rats with the highest level of anxiety, a lowered level of corticosterone with a constant level of neurometabolites in the hippocampus and striatum is characteristic. And only in rats with an intermediate level of anxiety, synchronization was observed between the increase in plasma corticosterone and the increase in hippocampal GABA content. The results obtained are in good agreement with the ideas of the protective action of glucocorticoids under PTSD manifested in  restraining violations of the psycho-physiological status. The mate rials allow the neurobiological mechanisms of the protective action of glucocorticoids to be detailed

Anxiety and neurometabolite levels in the hippocampus and amygdala after prolonged exposure to predator-scent stress

Here, to study the relationship between anxiety levels with changes in the neurometabolic profile in the hippocampus and amygdala, an experimental predator stress model was reproduced in which Sprague-Dawley rats were exposed to cat urine for 10 minutes on a daily basis for 10 days. At the time of presentation of the stimulus, an online survey of behavioral reactions was conducted. Fear, aggressiveness, avoidance of stimulus and grooming were recorded. Fourteen days after the completion of the last stress exposure, the total level of anxiety was determined in the test of the“cross maze”. Using the method of in vivo NMR spectroscopy, the content of neurometabolites was determined in the hippocampus and in the amygdala. According to the peculiarities of behavioral reactions to a stressor, animals were retrospectively divided into two phenotypes. The first phenotype used a passive behavioral strategy, and the second phenotype was active. In animals of the first phenotype, the indicators of anxiety behavior remained at the control level. In animals of the second phenotype, a decrease in anxiety was observed. Animals of the second phenotype showed elevated levels of lactate in the hippocampus compared to animals of the first phenotype, and the lowest N-acetylaspartate levels significantly differed from those in the control and the first phenotype animals. In the amygdala, in animals of the second phenotype, the content of taurine is sharply reduced in comparison with those in the control and the animals of the first phenotype. Thus, the results obtained indicate a relationship of post-stress changes in anxiety, with the peculiarities of the behavioral reactions presented at the moment of the immediate action of the stressor. Among the hippocampal and amygdala neurometabolites, the most informative for the characterization of the anxiolytic action of the predator stress are identified

Offensive behavior, striatal glutamate metabolites, and limbic–hypothalamic–pituitary–adrenal responses to stress in chronic anxiety

Variations in anxiety-related behavior are associated with individual allostatic set-points in chronically stressed rats. Actively offensive rats with the externalizing indicators of sniffling and climbing the stimulus and material tearing during 10 days of predator scent stress had reduced plasma corticosterone, increased striatal glutamate metabolites, and increased adrenal 11-dehydrocorticosterone content compared to passively defensive rats with the internalizing indicators of freezing and grooming, as well as to controls without any behavioral changes. These findings suggest that rats that display active offensive activity in response to stress develop anxiety associated with decreased allostatic set-points and increased resistance to stress. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.The Russian Science Foundation (grant № 17-15-013418) supported this study. This was supported in part by the contracts of the Ministry of Education and Science of the Russian Federation with South Ural State University (17.7255.2017/8.9) and Institute of Immunology and Physiology (AAAA-A18-118020690020-1). The work was furthermore supported by institutional funds from the State University of New York (SUNY) Upstate Medical University. This work is part of the TransCampus project between TU Dresden and King’s College London and was partially supported by the U.S. Department of Veterans Affairs (5101CX001219) and the U.S. Department of Defense (W81XWH-16-1-0773)