КИНЕТИКА ОКИСЛЕНИЯ СПЛАВА АК7М2 + 0,05%Sr, ЛЕГИРОВАННОГО ГЕРМАНИЕМ

There was investigated by means of thermogravimetric method kinetics of oxidation of cutting alloy АК7М2 + 0,05%Sr, germanium alloyed, in air at temperature 773, 798 and 823 K. There was identified that additives until 0,05 wt.% Ge will be reduced oxidation rate, as evidenced by increasing of value of apparent activation energy of oxidation process from 14,7 to 79,8 kJ/mol, which with increasing of Ge content until 1,0 wt.% again decreased to 25,2 kJ/mol. The value of actual velocity of oxidation is changed in the range (4,30÷6,00)·10–4 kg/(m2·c) depending on quantity of alloying component. In products of alloys oxidation together with γ-Al2O3 looked up phases SiO2 and GeO2.Термогравиметрическим методом исследована кинетика окисления твердого сплава АК7М2 + 0,05%Sr, легированного германием, в атмосфере воздуха при температурах 773, 798 и 823 К. Выявлено, что добавки до 0,05 мас.% Ge уменьшают скорость окисления, о чем свидетельствует увеличение величины кажущейся энергии активации процесса окисления от 14,7 до 79,8 кДж/моль, которая с повышением содержания Ge до 1,0 мас.% снова падает до 25,2 кДж/моль. Величина истинной скорости окисления меняется в пределах (4,30÷6,00)·10–4 кг/(м2·с в зависимости от количества легирующего компонента. В продуктах окисления сплавов наряду с γ-Al2O3 также обнаружены фазы SiO2 и GeO2

ВЛИЯНИЕ ИТТРИЯ НА АНОДНОЕ ПОВЕДЕНИЕ СПЛАВА АК1М2

Potentiodynamic method at a rate of 2 mV/s−1 potential sweep the corrosion−electrochemical behavior of the alloy AK1M2 doped yttrium electrolyte NaCl in the medium with different concentrations. It is shown that the addition of yttrium reduce corrosion rate of the anode alloy AK1M2 source nearly doubled. Increasing the concentration of chloride ions promotes the corrosion rate of the anode, regardless of the yttrium content in the alloy AK1M2. At the same time, and pitting corrosion potentials are shifted in the negative region. Потенциодинамическим методом со скоростью развертки потенциала 2 мВ ⋅ с−1 исследовано коррозионно− электрохимическое поведение сплава AК1М2, легированного иттрием в среде электролита NaCl различной концентрации. Показано, что добавки иттрия снижают скорость анодной коррозии исходного сплава AК1М2 почти в два раза. Установлено, что увеличение концентрации хлорид−ионов способствует росту скорости анодной коррозии независимо от содержания иттрия в сплаве АК1М2. При этом потенциалы коррозии и питтингообразования смещаются в отрицательную область.

Functional Modifications of Acid-Sensing Ion Channels by Ligand-Gated Chloride Channels

Together, acid-sensing ion channels (ASICs) and epithelial sodium channels (ENaC) constitute the majority of voltage-independent sodium channels in mammals. ENaC is regulated by a chloride channel, the cystic fibrosis transmembrane conductance regulator (CFTR). Here we show that ASICs were reversibly inhibited by activation of GABAA receptors in murine hippocampal neurons. This inhibition of ASICs required opening of the chloride channels but occurred with both outward and inward GABAA receptor-mediated currents. Moreover, activation of the GABAA receptors modified the pharmacological features and kinetic properties of the ASIC currents, including the time course of activation, desensitization and deactivation. Modification of ASICs by open GABAA receptors was also observed in both nucleated patches and outside-out patches excised from hippocampal neurons. Interestingly, ASICs and GABAA receptors interacted to regulate synaptic plasticity in CA1 hippocampal slices. The activation of glycine receptors, which are similar to GABAA receptors, also modified ASICs in spinal neurons. We conclude that GABAA receptors and glycine receptors modify ASICs in neurons through mechanisms that require the opening of chloride channels

System of Monitoring and Response to Public Health Emergencies of Sanitary-Epidemiological Character in the CIS Countries

The most important component of strengthening the potential for responding to biological threats both at the national and interstate levels is the formation of a unified system for monitoring and responding to emergencies (ES) of sanitary-epidemiological nature in the CIS territory.The aim of the work was to review the systems for monitoring and responding to emergencies of sanitary-epidemiological character in the CIS countries by the example of the Russian Federation, the Republic of Belarus, the Republic of Kazakhstan and the Kyrgyz Republic, to characterize the main areas of international cooperation on countering biological threats and coordinating international response measures in the CIS countries.Materials and methods. Information and analytical materials provided by organizations responsible for epidemiological surveillance and control in the CIS countries, Internet sources, and publications were used for the study.Results and discussion. The organization and functioning of the systems for monitoring and responding to emergencies in the CIS countries is a state function. It includes, as a rule, the national, regional (sub-national) and territorial (local) levels, which have horizontal and vertical connections. The legal framework is made up of documents of the legislative level. Interdepartmental interaction in response to emergencies is carried out both at the republican level and in administrative territories; the basis for interaction is the integrated planning of preventive and anti-epidemic measures and the functioning of the relevant organizational structures on an ongoing basis. Since 2015, with the support of the Government of the Russian Federation, programs have been implemented aimed at assisting partner countries in the implementation of the International Health Regulations (2005) in order to increase national response capacity and form a unified sanitaryepidemiological emergency response system in the CIS countries. The main areas of collaboration are strengthening the material and technical base and human resources of specialized institutions and scientific cooperation. As a result of the program implementation, a unified system for monitoring and prompt response to emergencies in the field of public health of sanitary-epidemiological nature has essentially been formed in the CIS countries to date, uniting more than 15 specialized institutions from 8 CIS countries

Does income inequality sand or grease the wheels of entrepreneurial activity? International evidence

© 2020 John Wiley & Sons Australia, Ltd Using a large panel of countries, this research examines the influence of income inequality on entrepreneurship. The impact of income disparities on entrepreneurship is not clear a priori—with a positive effect when inequality encourages entrepreneurship (“greasing effect”) or a negative effect when entrepreneurship discourages entrepreneurship (“sanding effect”). Our findings, across alternative measures of income inequality and even allowing for simultaneity, are consistent with the motivation or greasing effect. An equally insightful finding is that the effect of inequality switches across the prevalence of entrepreneurship—the sanding effect exists in nations with a low prevalence of entrepreneurship, and switches to a greasing effect as the prevalence of entrepreneurship increases. This is suggestive of positive network externalities from entrepreneurship—it takes a threshold level of entrepreneurship in a nation for greasing from income inequality to take hold

CLINICAL PICTURE, MODERN APPROACHES IN DIAGNOSTICS OF TRAUMATIC INTRACRANIAL HEMATOMAS

An analysis of 93 patients with traumatic intracranial hematomas of different degree of severity of craniocerebral trauma was made. The patients consist of 59 (63,4%) boys and 36 (36,6%) girls. In most cases, the cause of craniocerebral injury was a fall from variable-heights 56 (60,2%) patients. Cerebral symptoms dominate in examined children more than nidal symptoms. The evidence of meningeal symptoms was in direct proportion to the severity of brain contusion and disappeared by 7–8 days after trauma in majority of cases. In almost all cases, the traumatic intracranial hematomas were diagnosed on the basis of computerized tomographic system data. The choice of treatment strategy was determined according to neurological symptomatology and CT findings

Epidemiological Situation on Plague in 2020. Forecast of Episootic Activity of Natural Plague Foci in the Russian Federation and Other CIS Countries for 2021

The aim of the work was to substantiate the forecast of the epidemiological and epizootiological situation in natural foci of plague in the Russian Federation, countries of the near and far abroad for the year of 2021. Characteristics of the distribution of Yersinia pestis strains of the main subspecies (subspecies pestis) of medieval and antique biovars, Caucasian (ssp. caucasica) and central Asian (ssp. central asiatica) subspecies by 45 natural foci of the CIS countries are presented in the paper. The persistence of a multidirectional trend in the dynamics of epizootic activity of natural foci of the CIS countries with the circulation of Y. pestis pestis strains of the medieval biovar of the 2.MED1 phylogenetic branch and the antique biovar of the 0.ANT5, 4.ANT phylogenetic branches in the current decade has been outlined. For the Russian Federation, the development of epizootics is predicted in the Gorno-Altai highland and Tuva mountain natural foci caused by the circulation of Y. pestis pestis strains of the antique biovar 4.ANT and Y. pestis of the Altai biovar of the Central Asian subspecies 0.PE4a in 2021. For the Republic of Kazakhstan, there is a high probability of preserving epizootic activity in the North Aral, Aral-Karakum, Balkhash, Mojynkum, Taukum desert and Ili intermountain natural foci with the circulation of Y. pestis pestis strains of the medieval biovar of the phylogenetic branch 2.MED1. For the Kyrgyz Republic, the forecast for the development of plague epizootics caused by Y. pestis pestis strains of the antique biovar 0.ANT5 phylogenetic branch in the Sarydzhaz and Upper Naryn high-mountain natural foci has been substantiated. A high epidemic risk of epizootic manifestations caused by highly virulent strains of Y. pestis pestis of antique biovars 0.ANT5, 4.ANT and medieval biovar 2.MED1 for the entire territory of the CIS countries is noted. The relevance of implementing forecasts of the epidemiological situation into practice, taking into account the molecular-genetic and epidemiological characteristics of Y. pestis strains circulating in areas of expected epizootic manifestations of plague, is highlighted