Fly ash and phosphogypsum were used as Naturally Occurring Radioactive Materials (NORM) by-products for the synthesis of belite-sulfoaluminate clinkers. The influence of raw mixture composition and ...firing temperature was investigated. Clinkers and cements were examined by X-ray powder diffraction and scanning electron microscopy with energy dispersive X-ray spectroscopy. The compressive strength of the cements was determined after 28 days. Clinker phases identified included ye’elimite, ß-phase of belite, ternesite and gehlenite, while the main hydration product of the cement pastes was ettringite. The results showed that belite-sulfoaluminate cements can be fabricated with a compressive strength of 45.9 N/mm2 by firing the raw mixture (70 wt.% marl, 10 wt.% bauxite and 20 wt.% phosphogypsum) at a temperature of 1320°C/1h.
This study concerns the investigation of mortar layers and pigments of wall paintings from the Roman town of Emona (Ljubljana, Slovenia). Fragments of wall paintings consist of up to three preserved ...mortar layers. The mineralogical–petrographic compositions of the mortars were determined by means of optical microscopy and FT–IR spectroscopy. The investigated samples were divided into several groups based on similar thicknesses of the mortar layer, the binder colour and the composition of an aggregate. Furthermore, the results of mercury intrusion porosimetry showed that mortar layers consisting of carbonate grains exhibited lower porosity with respect to layers with mainly silicate grains, which is attributed to the angular shapes of carbonate aggregate. This is in accordance with the drilling resistance measurement system test (DRMS), confirming that layers with angular carbonate grains are harder than those with addition of rounded silicate ones, due to the good packing effect. The wall paintings were mainly executed using the fresco technique, while for some details secco was used. The identified pigments were red and yellow ochre, green earth, Egyptian blue, carbon black and lime white; all of them belonged to the so‐called austere pigment, which is quite common in Roman wall paintings.
The photocatalytic conversion of lignin, obtained from camelina (
Camelina sativa
), over titania and iron titanate films has been studied with analysis of the products using laser ...desorptiopn/ionization and high-performance liquid chromatography. The photocatalytic reaction over titania films leads to the formation of the mixture of compounds, such as phenol, vanillic acid, resorcinol, and
p
-coumaryl alcohol. In the presence of iron titanate films, the predominant reaction products are vanillic acid and
p
-coumaryl. The highest antioxidant activity has been revealed in the case of lignin conversion products obtained over nitrogen-containing iron titanate films under visible light exposure.
COVID-19 infection, preeclampsia and gestational diabetes mellitus in pregnancy cause similar changes in the placenta and influence development of the fetus between conception and birth in gestation. ...Proper uterine and placental vascularization is essential for normal fetal development. The transplacental exchange is regulated and maintained by the placental endothelium. During placental implantation, the trophoblast differentiates into two distinct layers, the inner cytotrophoblast and outer syncytiotrophoblast, which are key elements of the human placental barrier. Proinflammatory cytokines exacerbate ischemic events and create an upward spiral of an inflammatory reaction in the placenta. Placental pathology in gestational COVID-19 shows desquamation and damage of trophoblast and chronic histiocytic intervillositis. Similar lesions also occur in gestational diabetes mellitus and preeclampsia. The systemic inflammatory response of the mother, the increased inflammation in the placenta and cytokine production by placental trophoblasts should be monitored throughout pregnancy. Placental angiogenesis can be evaluated by serum vascular endothelial growth factor, Annexin A2, placental growth factor or sclerostin. Tissue damage can be assessed by measuring levels of serum lactate dehydrogenase and myeloperoxidase. Blood flow can be monitored with three-dimensional Doppler and pathological changes can be documented with paraffin-embedded tissue sections stained with hematoxylin and eosin, and electron microscope images as well as immunohistochemistry tests for vascular endothelial growth factor, placental growth factor, sclerostin and Annexin A2. The damage of maternal and fetal vascular perfusion (villitis and fibrin deposition) is a common mechanism of gestational diseases. The placenta lesions liberate anti-endothelial factors that lead to anti-angiogenic conditions and are the common mechanism of maternal placental vascular malperfusion in gestational diseases. Keywords: dysfunction, inflammation, pathology, placenta, pregnancy, vascularization
. In this research were described mast cells and secretory myocardiocytus of heart in a norm, and also changes of their consisting of heart of rats in the conditions of experimental aortic narrowing ...and at the action of epinephrin and deхamethazon. It is set that distinctions are in morphology of secretory components of different departments of heart. The study of the heart as an endocrine organ has attracted the attention of researchers for many years, but a number of issues remain debatable today. Of particular interest is the study of the morphology of the components of the heart, which are responsible for the synthesis, accumulation and secretion of biologically active substances. Aim: to establish the morphofunctional state of the secretory components of the heart in normal conditions and in the conditions of experimental hemodynamic overload of the heart. The material for the study was white rats, which were created with artificial coarctation of the aorta, the other two groups were exposed to adrenaline and dexamethasone. The number of SSG is the largest in the cardiomyocytes of the auricles of the heart, the smallest in the cardiomyocytes of the ventricles. There are differences in the morphofunctional state of tissue basophils in the ventricles, atria, and auricles, which is related to the differences in the structure of different parts of the heart. Hemodynamic overload of the myocardium is a powerful factor in the activation of the secretory components of the heart and stimulates the redistribution of topographic types of mast cells, the activation of their degranulation, which, under the conditions of prolonged action of the factor, leads to increased proliferation of fibroblasts and growth of connective tissue, which occurs during remodeling of the myocardium. Activation of secretory CMCs occurs in the form of an increase in secretory processes in the early stages of the effect of the factor, which can be considered as an additional reserve for compensation of overload. Adrenaline and dexamethasone have the opposite effect not only on the activity of tissue basophils of the heart, but also on their migration and number: the first activates the migration of mast cells into the perivascular space, the second inhibits the degranulation process due to its influence on the state of cell membranes.
Unsolved questions regarding the impact of electromagnetic radiation on the myocardium in conditions of a hypothyroid state require an in-depth study of this current and important modern problem. The ...purpose of the study is to establish macro- and microscopic changes in the myocardium of the heart of experimental animals under the conditions of modeling hypothyroidism under the influence of microwave electromagnetic radiation. The object of the study were the hearts of 126 laboratory sexually mature rats weighing 180-200 g, aged 4-6 months, divided into control and five experimental groups. This section of the experiment concerned the observation of the following experimental groups of rats: control; after thyroidectomy; after thyroidectomy and after exposure to microwave radiation for 45 minutes; after thyroidectomy and after exposure to microwave radiation for 120 min. Experimental animals were irradiated with microwave electromagnetic radiation with a frequency of 10 GHz, with a wavelength of 3 cm at different exposure times – 45 and 120 minutes – daily for 10 days. Studying the hearts of rats, we determined changes at the macro level in weight indicators of rat hearts. Analysis of changes at the level of the organ, i.e. the heart, showed that the greatest changes in heart weight were observed in the state of experimentally obtained hypothyroidism and the influence of ultra-high-frequency electromagnetic radiation with an exposure period of 120 minutes. Such an increase in the weight of the heart in the group of rats of this group was assessed by us as a destructive effect, which is associated with a more pronounced defibration of muscle fibers in the myocardium of the heart wall of the ventricles of rats, and, as a result, swelling of the interstitial spaces and disruption of blood supply at the microcirculatory level. During the morphological study under the conditions of modeling hypothyroidism after thyroidectomy at the microscopic level, destructive changes and degeneration processes of muscle fibers were observed in the myocardium. After thyroidectomy and exposure of microwave electromagnetic radiation for 45 minutes, we observed compensatory remodeling of unchanged structural components of the myocardium of the heart wall and hypertrophy of cardiomyocytes, which is evidence of the adaptive, reparative-regenerative effect of microwave electromagnetic radiation on the myocardium for 45 minutes. In a group of rats after thyroidectomy and exposure to microwave radiation with exposure for 120 minutes, an increase in degenerative-destructive processes in the myocardium with swelling of interstitial spaces was observed, which indicates the suppressive and destructive effect of microwave electromagnetic radiation of this term on cardiomyocytes.
With the beginning of a full-scale military invasion of Russian troops on the territory of independent Ukraine, the conditions and possibilities of providing educational services by higher education ...institutions in different regions of the country changed. The conduct of hostilities, the temporary occupation of certain regions, the destruction of infrastructure in the cities and villages of Ukraine, the need to stay in shelters, the lack of electricity supply and internet connection make full, high-quality provision of education impossible. In accordance with Article 571 of the Law of Ukraine “On Education” regarding state guarantees in the conditions of martial law, state of emergency or state of emergency, it is stated that those seeking education who are in conditions of martial law, state of emergency or state of emergency in Ukraine or its individual localities, declared in according to the established procedure (special period) were forced to change their place of residence (stay), leave their workplace, place of study, regardless of their place of residence (stay), for the duration of the special period, the organization of the educational process is guaranteed in a distance form or in any other form that is the safest for its participants. Distance education is gaining priority both in schools and in institutions of higher education. But in order to provide mass quality educational services, it is necessary to consider the peculiarities of the region in which the higher education institution is located. The central, western, and northwestern regions are able to conduct the educational process more or less calmly. Therefore, in our opinion, in such cities, higher education institutions can combine forms of education: to hold lectures online, and to work face-to-face with students in practical classes. Each higher education institution can choose which subjects and classes will be conducted remotely or face-to-face, guided by the Law of Ukraine “On Higher Education” and taking into account the specifics of the training of relevant specialists. But, in addition to providing high-quality educational services, which is the primary task of higher education institutions at any time, the safety of participants in the educational process is at the forefront: both those who seek education and employees of higher education institutions. The availability and provision of bomb shelters, shelters, the provision of medical and psychological assistance to students by teachers – all these issues are extremely important for ensuring a mass, high-quality and safe educational process in higher education institutions.
This study deals with the mineralogical and chemical characterization of archaeometallurgical material from the Roman archaeological site of Castra (Ajdovščina, western Slovenia). Samples were ...initially analysed via optical microscopy and X‐ray powder diffraction, with the composition of individual phases then determined using scanning electron microscopy coupled with electron‐dispersive spectroscopy, and Raman microspectroscopy. Chemical investigation was carried out by using inductively coupled plasma atomic emission spectroscopy to measure the major element content. The results showed that the slag originated from iron smithing operations, with calcium‐rich olivines, as well as wuestite and leucite, the most abundant phases. The investigated slags were also found to be characterized by significantly high lime levels, which probably promoted the formation of the calcium‐rich olivines.
This study concerns the microfacies characterization of white and black limestone tesserae from selected Roman floor mosaics in Slovenia, with the aim of defining their provenance. We investigated 42 ...tesserae from 15 different mosaics from the archaeological sites of Ljubljana, Izola, Mošnje, Ptuj, Črnomelj and Šentpavel, dated from the first century bc to the fifth century ad. Among the studied tesserae, 13 different microfacies were identified: eight black and five white. The most common were mudstones with ostracods (65% of black tesserae) and wacke‐packstones with miliolids (85% of white tesserae). The majority of the identified facies can be found in the Cretaceous successions of the Dinaric Carbonate Platform in south‐western Slovenia, north‐eastern Italy and south‐eastern Croatia, suggesting a regional or imported origin of the tesserae.
AGE CHANGES OF THE LIVER Poliakova, D. O.; Kramar, S. B.
Актуальні проблеми сучасної медицини: Вісник Української медичної стоматологічної академії,
03/2023, Letnik:
23, Številka:
1
Journal Article
Recenzirano
The purpose of the research is to analyze the results of scientific works devoted to the study of age-related changes in the liver and aging under the influence of various harmful factors.
Research ...material and methods. Analytical and bibliosemantic methods were used in the research. The search for scientific information on the topic of age-related changes in the liver and general scientific medical information was conducted using PubMed and Web of Science databases.
The results. The analysis of literary sources made it possible to establish that in the course of life, the human body undergoes a number of changes that lead to its aging. Physiological aging of the body is accompanied by irreversible functional and organic restructuring of all systems and organs, including the liver. The most common cause of diffuse changes in the liver parenchyma in elderly patients is steatosis, in the development of which mitochondrial dysfunction plays an important role. The problem of bad habits is also acute, because they inevitably accelerate the aging process in the liver itself and cause pronounced diffuse changes. This list includes alcohol consumption, smoking, and poor nutrition. Hereditary diseases are a separate direction of age-related changes in the liver. Without proper therapy, they accelerate the aging of the liver and the appearance of new chronic diseases associated with them.
It was also established that scientists have always sought to find reasons that affect the shortening of life, the mechanisms of liver aging, and the development of its age-related pathology. Along this path, hundreds of hypotheses have arisen that explain the essence of aging by the action of some single factor, say, a violation in one or another link of life support. One of the first synthetic theories of aging, based on the action of a complex system of factors, is the adaptive and regulatory function of the liver.
This theory is called adaptive because it sees the basis of aging in the reduction of the body's adaptive capabilities with age; and regulatory – because the shifts that occur are explained by a change in the mechanisms of regulation of exchange and function. According to the adaptation-regulatory theory, along with aging, a destructive process, the process of vitauktu (from vita - life, auktum - to increase) develops, aimed at stabilizing the viability of the liver and the body as a whole. This idea determined the tactics and strategy for solving this problem – to slow down the pace of aging and optimize the aging process and the adaptive capabilities of the body as much as possible.
Conclusions. For the treatment and prevention of liver diseases, against the background of inevitable aging, it is advisable to use drugs with a multidirectional effect on various links of the pathogenesis of liver lesions. Systematic implementation of preventive measures will allow older people to maintain good health and work capacity for many years.
PDF
