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Aim: The objective of the present study was to investigate the effect of treadmill training at lactate threshold intensity on maximum time to exhaustion (MTE) and heart rate (HR) as well as behavioral changes after kainate (KA)-induced status epilepticus (SE) of spontaneously hypertensive rats (SHRs).

In worrisome days of the Covid-19 pandemic that humanity is experiencing, national health systems are under great trial. In the foreground are questions that cannot be delayed. Some of them relate to the organization and capabilities of health care to adequately reflect the needs of aging people as one of the largest and most vulnerable population groups. Undoubtedly the world is experiencing a period of dynamic demographic changes and aging population on the planet. Globally, half a century the number of people aged over 60 has increased more than three times to reach almost 2 billion in 2050, according to the UN expert's report. Naturally, the rates of aging vary across countries and regions. In this connection, the national health systems today are facing great challenges: the population grows older, healthcare becomes more effective, but more expensive, the requirements of patients to the quality of health services raise more and more. Support healthy aging means both maintaining health throughout life to prevent health problems and disabilities from an early age, and address inequities in social, economic and environmental factors. Bulgaria is ranked 6th in the world for its rate of population aging. The country has a high relative share of residents aged 65+ approximately 21.3%. Three main demographic factors are contributing to the rapid population aging: emigration, high death rates and low birth rates. Those demographic factors have created numerous political, social and economic challenges for Bulgaria. In order to overcome them was developed a National Strategy for Demographic Development of Bulgaria for the period of 2012-2030. Positive fact is, that the gerontological and geriatric research in country has increased over the years. Large-scale studies, undertaken by our team of the Faculty of Public health in the Medical University-Sofia, referring to the different aspects of health cares for old persons, reveal major problem spheres in this direction. Purpose of the article is to analyze, summarize and indicate the priority actions to optimize the geriatric care in Bulgaria, based on results of this studies in the period 2007-2019 year. Methodology: Included respondents are 2973 people, as follows: 1240 healthcare professionals; 1510 persons over 60 years, consumers of health care, 223 family members and nurses from 12 nursing homes. Information was collected about their medical-social, educational and psychological problems. The following methods were used: documentary method; inquiry method; interview; statistical methods. Results: On the base of a critical analysis of the summarized results, we determined imperfections in the field of health care for older adults. There are considerable problems posed in front of the health services and social security institutions. Insufficient presence of gerontology and geriatrics in the academic spheres makes the development of adequate, modern geriatric structures difficult. Determined are the main reasons for the difficulties of health professionals in taking care for their patients. Medical specialists often lack the necessary knowledge and understanding into medico-social questions and problems posed by their older patients. Conclusions: The tendency is to increase needs and demands of society for quality health and social care of adults, carried out by competent professionals. The need for long-term services and supports in Bulgaria will continue to increase as the population ages. Health problems of older adults require new organizational approaches in health policy and practice. Recommendations: It is necessary to ensure appropriate conditions for achieving diversity in structures and levels of health care and the application of integrated approaches to prevention and treatment in order to achieve a better quality of life for aging population in Bulgaria. Approaches to addressing the challenges of geriatric care in Bulgaria are discussed. [ABSTRACT FROM AUTHOR]

This paper makes a study of a three-phase 16-pole generator with axial magnetic field and permanent Nd-Fe-B magnets. An equivalent magnetic circuit for a single winding of the generator has been created at the outset, and an equivalent electromagnetic circuit has been obtained from it. Expressions for the r.m.s. value of the induced electromotive force have been derived both for a winding and for a phase. The expressions account for the impact of the construction parameters of the generator on the size of the winding and the phase. Simulation has been realized in Simulink (MATLAB environment) and the main output electric characteristics of the three-phase generator have been obtained for one phase, wherein the phase currents and voltages, as well as the active power, have been defined as a function of the generator's revolutions per minute. Experimental studies have been conducted in order to test the obtained model and it has been established that the model simulates with good precision the operation of the studied three-phase generator. [ABSTRACT FROM AUTHOR]

A method is proposed, allowing assessing the influence of the grain size on the attenuation coefficient of ultrasound waves in metallic samples, by means of the maximum and minimum positive semi-waves within a transition process, caused by a rectangular signal waveform. Steel samples have been made and tempered at different temperatures for an hour. The generator of rectangular impulses has been set to the resonance frequency of both the piezo-transmitter and the piezo-receiver, and therefore the signal, measured by the oscilloscope, is big enough for direct processing. An averaged coefficient of compliance has been obtained, by means of which the diameter of the grains can be calculated for the corresponding sample. [ABSTRACT FROM AUTHOR]

This paper makes a study of a three-phase disk type synchronous 8 pair-pole generator with axial magnetic field and rare earth magnets. The generator consists of one rotor with sixteen rare earth magnets and two stators with twenty four windings each, connected in a star, eight in a phase. A preliminary obtained expression for calculating the e.m.f. in a winding is used initially, where the geometric dimensions of the generator, the materials it is made of, as well as the parameters of both its windings and its rare earth magnets have been taken into consideration. Then the equivalent parameters of the two stators, connected in parallel, are found. By means of the obtained model the phase voltages of the model structure at idle running are calculated. Then a three-phase symmetric active load, also connected in a star, is added to the equivalent circuit, and the output electrical parameters are calculated – the phase voltages on the three-phase load and the currents through it, as well as the emitted full r.m.s.value. Experimental studies of the output electrical parameters of the considered three-phase generator under the modes of idle running and at an active three-phase load have been conducted with both stators connected in parallel. The basic output characteristics, obtained from the model, have been compared to those, from the conducted experimental measurements. [ABSTRACT FROM AUTHOR]

An analytic time series in the form of numerical solution (in an appropriate finite time interval) of the Hodgkin-Huxley current clamped (HHCC) system of four differential equations, well known in the neurophysiology as an exact empirical model of excitation of a giant axon of Loligo, is presented. Then we search for a second-order differential equation of generalized Fitzhugh-Nagumo (GFN) type, having as a solution the given single component (action potential) of the numerical solution. The given time series is used as a basis for reconstructing orders, powers, and coefficients of the polynomial right-hand sides of GFN equation approximately governing the process of action potential. For this purpose, a new geometrical method for determining phase space dimension of the unknown dynamical system (GFN equation) and a specific modification of least squares method for identifying unknown coefficients are developed and applied. [ABSTRACT FROM AUTHOR]