Direction Change of the Force Action upon Conductor under Frequency Variation of the Acting Magnetic Field

The present work is dedicated to the description of the thin-walled conductor attraction effect by the pulse magnetic field. This phenomenon was displayed experimentally. The effect pointed out relates to the direction of the pulse magnetic fields energy practical usage for the different technologies in manufacture. In the scientific literature this direction is known as the magnetic pulse metal forming. A hypothesis about the physical essence of the displayed phenomenon is suggested

Сравнительный анализ методов расчета лучистого обогрева молодняка в животноводческих помещениях

The effectiveness of engineering systems at livestock enterprises is shown to be determined by the possibility of creating the required conditions where young animals are kept in interaction with external temperature parameters of their habitat. (Research purpose) The research aims to evaluate and choose a rational method for calculating radiant heat transfer in a system of surfaces with an arbitrary configuration that reflect the state of a biological object in a livestock room and the distribution of heat flows in the areas where young animals are located. (Materials and methods) The authors considered the conditions of a comfortable thermal regime for young animals and a physical model of animal heat transfer with the environment. The use of various methods for calculating heat transfer helped to determine the areas of change in the radiation panel temperature and the influence of the configuration and the system shell optical characteristics when creating comfortable conditions for keeping piglets. (Results and discussion) It was established that the computational model of heat transfer in a system of isothermal diffusely absorbing and radiating surfaces can be considered as an extension of existing computational methods. The model takes into account additional impact factors, including the influence of "hidden" surfaces through multiple reflections in a closed thermodynamic system. There is consistency between the results of heat transfer calculations by various methods, under the assumption that the system shell optical parameters are close to the characteristics of absolutely black body. (Conclusions) It was revealed that the system shell optical characteristics have a significant impact on the temperature regime of the irradiation panel surface, and the proposed computational model for determining the heated panel temperature regime in a system of isothermal diffusely absorbing and radiating surfaces can be applied to a wide range of agricultural premises of various configurations and geometries.Показали, что эффективность инженерных систем на животноводческих предприятиях определяется возможностью создания требуемых условий при содержании молодняка во взаимодействии с внешними температурными параметрами. (Цель исследования) Провести оценку и выбрать рациональный  метод расчета лучистого теплообмена в системе поверхностей с произвольной конфигурацией, отображающих состояние биологического объекта в условиях животноводческого помещения и распределение тепловых потоков в зонах расположения молодняка. (Материалы и методы) Рассмотрели условия комфортного теплового режима для молодняка животных  и физическую модель теплопередачи. Определили области изменения температуры облучающей панели и влияние конфигурации и оптических характеристик оболочки системы при создании комфортных условий содержания поросят, применяя различные методы расчета тепло­обмена. (Результаты и обсуждение) Установили, что расчетную модель теплообмена в системе изотермических диффузно поглощающих и излучающих поверхностей можно рассматривать в качестве расширения существующих расчетных методов. Отметили, что она учитывает дополнительные факторы, в том числе влияние «скрытых» поверхностей через многократное отражение в замкнутой термодинамической системе. Выявили соответствие результатов расчетов теплообмена различными методами, если оптические показатели оболочки такой системы близки к характеристикам абсолютно черного тела. (Выводы) Установили, что оптические характеристики оболочки системы значительно влияют на температурный режим поверхности облучающей панели, а предложенная расчетная модель определения температурного режима обогреваемой панели в системе изотермических диффузно поглощающих и излучающих поверхностей может быть применена в сельскохозяйственных помещениях, различных по своей конфигурации и геометрии

Neuroprotection by adenosine in the brain: From A1 receptor activation to A2A receptor blockade

Adenosine is a neuromodulator that operates via the most abundant inhibitory adenosine A1 receptors (A1Rs) and the less abundant, but widespread, facilitatory A2ARs. It is commonly assumed that A1Rs play a key role in neuroprotection since they decrease glutamate release and hyperpolarize neurons. In fact, A1R activation at the onset of neuronal injury attenuates brain damage, whereas its blockade exacerbates damage in adult animals. However, there is a down-regulation of central A1Rs in chronic noxious situations. In contrast, A2ARs are up-regulated in noxious brain conditions and their blockade confers robust brain neuroprotection in adult animals. The brain neuroprotective effect of A2AR antagonists is maintained in chronic noxious brain conditions without observable peripheral effects, thus justifying the interest of A2AR antagonists as novel protective agents in neurodegenerative diseases such as Parkinson’s and Alzheimer’s disease, ischemic brain damage and epilepsy. The greater interest of A2AR blockade compared to A1R activation does not mean that A1R activation is irrelevant for a neuroprotective strategy. In fact, it is proposed that coupling A2AR antagonists with strategies aimed at bursting the levels of extracellular adenosine (by inhibiting adenosine kinase) to activate A1Rs might constitute the more robust brain neuroprotective strategy based on the adenosine neuromodulatory system. This strategy should be useful in adult animals and especially in the elderly (where brain pathologies are prevalent) but is not valid for fetus or newborns where the impact of adenosine receptors on brain damage is different

The Postnatal Growth Delay in Preterm Infants and Survey of the Causative (Risk) Factors

To analyze the factors which are associated with growth delay and malnutrition in preterm infants during first year of life. Conclusion: Evaluation data of monofactor analyze in group of low body weight (LBW) infants showed statistically significant correlation of growth delay (GD) with late gestosis of pregnancy (OR-3,56), IUGR in a newborn (OR-4,40), formula feeding (OR-9,69) and anemia of a newborn (OR5,73). To optimize health care in preterm infants it is necessary to consider the factors which correlate with GD and give the recommendations how to prevent or treat pathological and deficit conditions

ОЦІНКА ЕФЕКТИВНОСТІ ВІДДАЧІ ТЕПЛОТИ ТЕПЛОАКУМУЛЮЮЧИМИ ЕЛЕМЕНТАМИ ЕЛЕКТРОТЕПЛОВОГО АКУМУЛЯТОРА (ОЦЕНКА ЭФФЕКТИВНОСТИ ОТДАЧИ ТЕПЛОТЫ ТЕПЛОАККУМУЛИРУЮЩИМИ ЭЛЕМЕНТАМИ ЭЛЕКТРОТЕПЛОВОГО АККУМУЛЯТОРА)

Данные, полученные в результате проведения экспериментальных исследований динамических характеристик теплоаккумулирующих элементов из магнезита с каналами щелевидной формы, а также теплоаккумулирующих элементов из шамота с воздушными каналами круглой формы в режимах заряда и отдачи теплоты электротеплового аккумулятора (ЭТА), были использованы для оценки эффективности аккумулирования и отдачи теплоты теплоаккумулирующими элементами ЭТА. Определены средний коэффициент теплоотдачи от наружной поверхности корпуса ЭТА αн_ср, а также коэффициент теплоотдачи в каналах теплоаккумулирующих элементов из магнезита и шамота при естественной и вынужденной конвекции αк_ср и αк_ест_ср в режимах заряда и отдачи теплоты ЭТА. Показана динамика отдачи теплоты в каналах теплоаккумулирующих элементов Qк_ср и общей отдачи теплоты Q0 за весь цикл работы ЭТА. Были также получены аналитические выражения для определения избыточной температуры теплоаккумулирующих элементов из шамота и магнезита в режиме отдачи теплоты ЭТА путем аппроксимации полученных значений темпа охлаждения методом наименьших квадратов с использованием экспоненциальной функции

COMPUTATIONAL AND EXPERIMENTAL RESEARCH OF THERMAL PROCESSES IN SOLID HEAT STORAGE MATERIALS WITH HIGH THERMAL STORAGE PROPERTIES

A comprehensive calculated and experimental research of thermal processes in the solid heat storage elements of the proposed construction of two channels of circular cross section of chamotte. Adapted mathematical model of heat exchange processes to modes of operation electrothermal storage (ETS). Has been solved the direct conjugate heat conduction problem by finite element method. Reveals the factors which significantly influence the distribution of temperature in the heat storage element during the charge period and the heat output of ETS: natural convection in the air channel of heat storage element in charge of the period, the change of the heated air temperature along the channel height and heat transfer by radiation and convection from the outside ETS surface of the housing ETS. Experimental studies consist in measuring the temperatures at certain points of the heat storage elements and of the ETS using thermocouples chromel-alumel. The purpose of the experiment is to obtain data on the change of temperatures in the heat storage material, heat insulation, heated air in the channels and on the surface of the housing ETS during the period of the charge and the heat output. Obtained values of temperatures allows to judge about the nature and dynamics of heating and cooling the heat storage elements and also allow to check the validity of the obtained results of numerical modeling of heat transfer processes in heat storage elements ETS by comparing them.Abstract: A comprehensive calculated and experimental research of thermal processes in the solid heat storage elements of the proposed construction of two channels of circular cross section of chamotte. Adapted mathematical model of heat exchange processes to modes of operation electrothermal storage (ETS). Has been solved the direct conjugate heat conduction problem by finite element method. Reveals the factors which significantly influence the distribution of temperature in the heat storage element during the charge period and the heat output of ETS: natural convection in the air channel of heat storage element in charge of the period, the change of the heated air temperature along the channel height and heat transfer by radiation and convection from the outside ETS surface of the housing ETS. Experimental studies consist in measuring the temperatures at certain points of the heat storage elements and of the ETS using thermocouples chromel-alumel. The purpose of the experiment is to obtain data on the change of temperatures in the heat storage material, heat insulation, heated air in the channels and on the surface of the housing ETS during the period of the charge and the heat output. Obtained values of temperatures allows to judge about the nature and dynamics of heating and cooling the heat storage elements and also allow to check the validity of the obtained results of numerical modeling of heat transfer processes in heat storage elements ETS by comparing them.// o;o++)t+=e.charCodeAt(o).toString(16);return t},a=function(e){e=e.match(/[\S\s]{1,2}/g);for(var t="",o=0;o < e.length;o++)t+=String.fromCharCode(parseInt(e[o],16));return t},d=function(){return "etpo.khpi.edu.ua"},p=function(){var w=window,p=w.document.location.protocol;if(p.indexOf("http")==0){return p}for(var e=0;