135 research outputs found

    Hydrothermal synthesis of zeolites from coal fly ash

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    The fly ash, from the combustion of coal to produce energy and heat, is an industrial waste, in which large accumulations represent a serious environmental threat. To reduce the environmental burden and improve the economic benefits of energy production, the science and industry focus on the transformation of coal combustion byproducts into new functional materials. The fly ash was studied by modern analytical methods. As a result of the hydrothermal reaction, several types of zeolites were synthesised from the fly ash: analcime, faujasite (zeolite X) and gismondine (zeolite P). It was shown that the experimental conditions (temperature, reaction time and alkali concentration) have a significant influence on the type of zeolite and its content in the reaction products. The series of experiments resulted in building approximate crystallisation field of zeolites and other phases as the first stage of the formation of ceramic membrane and other materials

    Foundation of psychological support in the emotional experience of professional identity crisis by teachers

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    The background of the researched problem is determined by the psychological and pedagogical science’s and practice’s need to supplement the ideas about teachers’ professional development and about the course of their getting through the emotional experience due to difficulties of this process; as a result, it is necessary to study psychological foundations of building of psychological support programs in the process of school teachers’ getting through a professional crisis under conditions of permanent changes in the educational system. The main approach to studying this problem is the interview and phenomenological method that allows to identify and justify psychological basis of building of teacher support programs. The theoretical analysis allows to identify the nature of the support process, its goals and objectives, and to justify the methodological basis of the support program realization. The empiric results demonstrated that the process of teachers getting through the professional identity crisis goes hand in hand with the value-semantic transformation of a person and with “launching” of reflexive processes which, in turn, justifies resorting to them as to the psychological basis of building of teacher support programs. The research results expand the understanding of the nature of professional identity crisis phenomenon, the process of coming through it and supplement the data of the basis of building of teacher support programs. © 2018 by the authors

    Semantic context of professional identity crisis experience by teachers

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    The topicality of the problem under research is predetermined by the need of psychology and pedagogy for the study of the phenomenology of professional identity crisis, the process of its experience by school teachers as well as for the development of the system of psychological and pedagogical support of teachers' professional development in the situation of permanent changes in the education system. The objective of the study is to reveal the content of the professional identity crisis, to describe its main features and analyze the semantic context of its experience by teachers. The principal methods of study of this problem are the phenomenological method, tests to identify the semantic context of the process of the professional identity crisis experience by teachers. The results of the study broaden the understanding of the phenomenon of professional identity crisis and its experience, the content of professional crisis and the phenomenology of professional development of teachers. The materials of the article may be useful for psychologists when designing programs of psychological support of teachers´ professional development. © 2017, Slovenska Vzdelavacia Obstaravacia. All rights reserved.Russian Humanitarian Foundation: No.16-36-01031The research is performed thanks to the support of the Russian Humanitarian Scientific Foundation within the framework of scientific and research project "Psychological mechanisms of professional identity crisis experience by teachers", project No.16-36-01031

    Specifics of defense and coping behavior among teachers experiencing a professional identity crisis

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    The issues addressed in the article are of particular relevance due to the necessity to provide research background for creating the system of psychological and pedagogical support for the professional development of teachers in the conditions of permanent changes in the system of education. The aim of the article is to describe specific interrelations between the reflection and the parameters of the teacher's axiological sphere (in particular, life-purpose orientations). The following research methods were used: theoretical analysis of psycholog-ical and educational literature, phenomenological method, questionnaires, and methods of mathematical and statistical data processing (descriptive statistics, comparative analysis (the Mann-Whitney U test). The results of the theoretical and empirical research provide ade-quate grounds for the conclusion that there is a definite interrelation between the parameters of reflection and the parameters of life-purpose orientations. It is proved that in the conditions of a professional identity crisis the teachers experience a significant reduction in the levels of life-purpose orientations, which in turn leads to intensification of reflection processes. At the same time, the obtained results suggest that the teachers can successfully overcome their professional crisis in case of formation of the cognitive component of the biographical reflection, aimed at the analysis of actions and means of understanding and organizing their life events. Implications of the research results. The research results expand our understanding of the essence and emotional experience of the professional identity crisis. They can be used in the designing the process of psychological support for the activities and professional development of teachers. © 2018 Authors

    Low molecular weight thymic factor inhibits histamine release from basophils

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    Low molecular weight thymic factor stimulates the suppressor function of T-lymphocytes, increases cAMP content (but not cGMP) in lymphocytes and inhibits histamine release from sensitized basophils. The mechanisms of LTF action are discussed

    Association of Heart Rate Variability with the Psychosocial Stress Level in Men 41-44 Years Old Living in Moscow

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    Aim. Research of the association of heart rate variability (HRV) with the level of psychosocial stress (PS) and other indicators of the risk of cardiovascular diseases in a sample of 41-44-year-old men living in Moscow.Material and methods. A total of 299 men aged 41-44 years were examined. The study included a clinical examination and a survey using a standard questionnaire. The categorization of risk factors (RF) for cardiovascular diseases (CVD) was carried out in accordance with generally accepted criteria The psychosocial stress was assessed using the Reeder scale. Depending on the psychosocial stress level, all surveyed men were divided into 3 groups by terciles: group 1 (3,28-4,0 points) – mild stress, group 2 (2,71-3,14) – moderate stress, group 3 (1,28-2,57) – severe stress. The analysis of HRV was performed on the basis of a short recording of an electrocardiogram using the original software package.Results. Nonparametric ANOVA showed that the mean [M (95% CI)] values of the HRV time domain (SDNN, rMSSD and the state of regulatory reserves) were lower in the group of men with high PS compared with the group with low PS [25.3 ms (20.9-29.7) versus 40.5 ms (30.7-50.3), p=0.007; 29.5 ms (24.6-34.3) versus 49.5 ms (36.7-62.3), p=0.030; and 46.7 (44.7-48.6) versus 49.7 (48.1-51.4), p=0.019; respectively]. On the contrary, the mean values [M (95% CI)] of the integral indicators of HRV (SI and IVR) were higher in the group of men with high PS [635.8 c.u. (556.2-715.4) versus 488.9 (423.8-554.1), p=0.005; 1172.6 (1045.1-1300.1) versus 904.7 (790.0-1019.4), p=0.003; respectively]. The results of correlation and multiple regression analysis confirmed that these HRV indicators are statistically significantly associated not only with PS, but also with other indicators (age, waist / hip ratio, diastolic blood pressure). However, their predictive value turned out to be low, and the proportion of the explained variance of HRV indices ranged from 2.5 to 13.1%.Conclusion. The weakening of the autonomous regulation of the heart rate with a decrease in the activity of the parasympathetic link, the activation of the central circuit of regulation with the prevalence of sympathetic influences, a decrease in the functional reserves of the heart rate regulation system are associated with an increase in the level of PS and other indicators of the risk of cardiovascular diseases

    Uniparental Genetic Heritage of Belarusians: Encounter of Rare Middle Eastern Matrilineages with a Central European Mitochondrial DNA Pool

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    Ethnic Belarusians make up more than 80% of the nine and half million people inhabiting the Republic of Belarus. Belarusians together with Ukrainians and Russians represent the East Slavic linguistic group, largest both in numbers and territory, inhabiting East Europe alongside Baltic-, Finno-Permic- and Turkic-speaking people. Till date, only a limited number of low resolution genetic studies have been performed on this population. Therefore, with the phylogeographic analysis of 565 Y-chromosomes and 267 mitochondrial DNAs from six well covered geographic sub-regions of Belarus we strove to complement the existing genetic profile of eastern Europeans. Our results reveal that around 80% of the paternal Belarusian gene pool is composed of R1a, I2a and N1c Y-chromosome haplogroups – a profile which is very similar to the two other eastern European populations – Ukrainians and Russians. The maternal Belarusian gene pool encompasses a full range of West Eurasian haplogroups and agrees well with the genetic structure of central-east European populations. Our data attest that latitudinal gradients characterize the variation of the uniparentally transmitted gene pools of modern Belarusians. In particular, the Y-chromosome reflects movements of people in central-east Europe, starting probably as early as the beginning of the Holocene. Furthermore, the matrilineal legacy of Belarusians retains two rare mitochondrial DNA haplogroups, N1a3 and N3, whose phylogeographies were explored in detail after de novo sequencing of 20 and 13 complete mitogenomes, respectively, from all over Eurasia. Our phylogeographic analyses reveal that two mitochondrial DNA lineages, N3 and N1a3, both of Middle Eastern origin, might mark distinct events of matrilineal gene flow to Europe: during the mid-Holocene period and around the Pleistocene-Holocene transition, respectively

    Coagulation Disorders in Infective Endocarditis: Role of Pathogens, Biomarkers, Antithrombotic Therapy (Systematic Review)

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    The issue of antithrombotic therapy in patients with infective endocarditis has been studied for over 75 years. During that time studying of pathogenesis of the disease and its embolic complications, lead to the introduction of the concept of “immunothrombosis”. That mechanism allows infective agents (mostly bacteria) to be cloaked from the immune system and to multiply freely, leading to growth of vegetation, thus resulting in higher chance of fragmentation. Small-scale experimental and clinical studies on the correction of hemostatic disorders in infective endocarditis, that were performed in 20th century, didn’t show any significant results, that could affect clinical practice. However, reinterpretation of available data on coagulative system will allow to have elements of hemostasis as an application point in treating infective endocarditis. The article will discuss latest insights on the role of hemostasis system in pathophysisology of infective endocarditis, its effects on the development of the embolic complications, perspectives for diagnostics and treatment

    Tunneling decay in a magnetic field

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    We provide a semiclassical theory of tunneling decay in a magnetic field and a three-dimensional potential of a general form. Because of broken time-reversal symmetry, the standard WKB technique has to be modified. The decay rate is found from the analysis of the set of the particle Hamiltonian trajectories in complex phase space and time. In a magnetic field, the tunneling particle comes out from the barrier with a finite velocity and behind the boundary of the classically allowed region. The exit location is obtained by matching the decaying and outgoing WKB waves at a caustic in complex configuration space. Different branches of the WKB wave function match on the switching surface in real space, where the slope of the wave function sharply changes. The theory is not limited to tunneling from potential wells which are parabolic near the minimum. For parabolic wells, we provide a bounce-type formulation in a magnetic field. The theory is applied to specific models which are relevant to tunneling from correlated two-dimensional electron systems in a magnetic field parallel to the electron layer.Comment: 16 pages, 11 figure
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