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As a result of generalization of geophysical studies, petro-paleomagnetic and structural-geomorphological analyses, as well as thermodynamic modeling, some features of ore formation in the hydrothermal system of Cape Fiolent (southwestern Crimea) under island arc conditions were revealed.It has been established that the main transformations of rocks of the Middle Jurassic igneous complex of Cape Fiolent occurred under the influence of hydrothermal fluids during the introduction of felsic intrusions during 168–140 Ma. The zones contain sulfide mineralization, the main minerals of which are pyrite, sphalerite, pyrrhotite, galena, chalcopyrite and arsenic pyrite. In the central parts of the hydrothermal alteration zone, massive sulfides are strongly weathered; these zones contain many secondary sulfates. In the marginal parts of hypergenic limonite, yellow-brown goethite prevails in the oxidation zone, yellow jarosite in the center, which is probably due to the large amount of pyrite in the center of the system, which gave more sulfuric acid during oxidation. The presence of native sulfur in the section testifies to the mixing of the acidified hydrothermal solution with seawater. Complex petro-paleomagnetic and magnetometric studies have shown that contact changes and transformation of the contrasting basalt-rhyolite formation occurred along the NNW-trending faults.

To get properties and characteristics of oil and gas source rocks and for other geological aims, geologists analyzes core samples from wells and outcrop samples. But we should probably somehow correct geochemical source rock properties data we get on outcrop samples, because organic matter could change significantly due to oxidizing and weathering. This problem is very important but poorly developed in modern publications, so it attracted our interest and led to this investigation. Published information on the organic matter weathering which change it’s content and quality in sedimentary rocks is collected and summarized in this article. The changes of the kerogen (isolated from the mineral matrix) elemental composition during its long-term storage are presented.We compared the results we get in laboratory and results of other authors who dealt with natural changes of organic matter in outcrops. An attempt to interpret the results obtained from the point of view of hypergene changes in OM was made. Uncertainties that require further study and development are indicated. This work is the first step to better understanding of weathering effect on organic matter content and properties – question of great importance for making adequate oil and gas prospects estimations.This study continues the work of our foregoers and Teachers – geochemists of the Petroleum Geology Department of Lomonosov Moscow State University: N.B. Vassoevich, Yu.I. Korchagina, O.A. Radchenko, V.A. Uspensky, I.E. Leifman, A.N. Guseva, O.K. Bazhenova, T.A. Kiryukhina.

The article discusses the fundamental possibilities of using the results of geochemical and hydrogeochemical studies of organic matter, oils and waters in oil and gas geology, including for objects at the stage of development. It is shown that complex geochemical studies of oils and waters make it possible to get more correct conclusions about the presence or absence of fluid-dynamic connectivity of different horizons. Studies of organic matter and oils allow (by basin modeling instrument) to understand the contribution of different source rocks to formation of oils of different reservoirs. Hydrogeochemical studies of associated waters and waters used in the reservoir pressure maintenance system in a complex of works not only actively complements the knowledge about the presence or absence of fluid-dynamic connections between reservoirs and production objects, but also make it possible to predict, for example, salt deposition on equipment and in the reservoirs, and therefore allow you to prevent the possibility of unwanted salt deposition. The conclusions are based on the results of comprehensive geological and geochemical studies carried out by the authors for one of the deposits of the Krasnoleninsky arch of Western Siberia, which is at the development stage, as well as on the previous experience of the authors.

This article presents results of a study of bryophytes in seven caves of the Kutuk tract of the National Park «Bashkiria» of the Republic of Bashkortostan, including the largest cave in Bashkiria – Kutuk-Sumgan.Fifty-five bryophytes species were found in the studied caves. The dominant species in all caves was Timmia bavarica. The species composition of bryophytes of each cave is unique. Among identified bryophytes species 23, species were found only in one cave, and 11 species in 2 caves. During our survey, we found 31 species in Kutuk-Sumgan Cave, 21 species in Kutuk-2 and Kutuk-3 caves, 19 species in Kutuk-4 caves, 18 species in Vintovaya and Zigzag caves and 14 species in Kutuk-1 cave. Using the Jaccard and Phi-squared similarity indices, we revealed the stability of the bryoflora of the caves in different years and show its changes. Changes in the composition and structure of mosses in the Kutuk tract may be caused by mechanical influences. Benchmark similarity analysis allowed us to determine the influence of entrance morphology and glaciation in the photic zone of the caves on the composition of bryophytes.Using the Kutuk tract caves as an example, it is shown that in the primary analysis of the bryoflora, when selecting a characteristic cave, up to 40% of the total species composition of the caves can be identified in a single cave. The current study of Kutuk tract caves shows that identification of the primere analyses of bioflora permits identification of up to 40% of species composition of an individual cave.Three criteria for selecting a characteristic cave were identified: size of the photic zone and morphology of the entrance, diversity of habitats, and the least degree of disturbance.

Aim. To evaluate the prevalence of cardiovascular events and death depending on baseline coronary collateral blood flow (CBF) in five year follow-up of stable coronary heart disease (CHD) patients.Material and methods. To the study, 579 stable CHD patients included, who during scheduled coronary angiography (CAG) were diagnosed with at least one stenosis in one coronary artery (diameter no less than 1,5 mm), narrowing its lumen by ≥50%. CBF was assessed by Rentrop modified method. In 5 years post index CAG, the cardiovascular events were counted (relapse or worsening of functional class of angina, non-fatal myocardial infarction, coronary bypass surgery, acute stroke) and mortality.Results. In multifactorial analysis (Cox regression) the association revealed of the good CBF with lower cardiovascular mortality (HR 0,5; р=0,02) and all-cause mortality (HR 0,5; р=0,004). In multifactorial analysis (logistic regression) there was association of good CBF with lower rate of relapse/worsening of angina in long term period — (OR 0,36, p=0,002). There was no relation found for CBF condition and non-fatal myocardial infarction, percutaneous coronary intervention.Conclusion. By the data from five year follow-up, good CBF correlates with less cardiovascular and all-cause mortality and with the frequency of relapse/worsening of the FC of angina pectoris in chronic CHD patients, including those underwent revascularization, regardless of the severity of disease, coronary flow lesion and other factors associated with cardiovascular complications.

Hypoglycemia in congenital hyperinsulinism (WGI) in children increases the risk of brain damage, seizures and development delay. The aim of our study was to evaluate the clinical manifestations in children with CHI. Hypoglycemia is often manifests with seizures, which are sometimes in the future may lead to the development of epilepsy. Seizures in CHI do not always require a diagnosis of epilepsy and prescription of anticonvulsants. EEG changes in these children may be observed in the absence of epileptic seizures. Developmental delay was more common in children with neurological abnormalities and MRI changes. Children with ABCC8 gene mutations have more complicated for CHI and more prominent developmental delay.

The article describes the main clinical forms and causes of speech delay in children. It presents modern data on the role of neurobiological factors in the speech delay pathogenesis, including early organic damage to the central nervous system due to the pregnancy and childbirth pathology, as well as genetic mechanisms. For early and accurate diagnosis of speech disorders in children, you need to consider normal patterns of speech development. The article presents indicators of pre-speech and speech development in children and describes the screening method for determining the speech delay. The main areas of complex correction are speech therapy, psycho-pedagogical and psychotherapeutic assistance, as well as pharmaceutical treatment. The capabilities of drug therapy for dysphasia (alalia) are shown.

Treatment of developmental disorders, correction of learning disabilities and behavioral problems in children should be prompt, complex and include pharmacotherapy with nootropic agents. The results of recent studies shown in this review proved effectiveness of pharmacotherapy with pyritinol in children with perinatal injury of central nervous system and its consequences, psychomotor and speech development delay, dyslexia, attention deficit/hyperactivity disorder, cognitive disorders and learning disabilities (including manifestations of epilepsy, chronic tic disorders and Tourette syndrome). Due to its ability to optimize metabolic processes in central nervous system, pyritinol is used in treatment of vegetative dysfunction in children and adolescents, especially associated with asthenical manifestations, as well as in complex therapy of exertion headache and migraine. The drug is effective in treatment of cognitive disorders in children and adolescents with epilepsy, pyritinol was administered without changing of the basic anticonvulsive therapy and no deterioration (increase of severity of seizures or intensity of epileptiform activity on electroencephalogramms) was observed. Significant nootropic effect of pyritinol, including neurometabolic, neuroprotective, neurodynamic and other mechanisms, in association with safety and rare side effects of this drug determines its wide usage in pediatric neurology.

Clinical observation of the patient with dilated cardiomyopathy, developed after chemotherapy for breast cancer.

The catalytic layers are designed and synthesized using sol–gel technology with the aim of improving catalytic layers and membranes of polymer fuel cells. The layers synthesized consist of a silicate matrix with uniformly distributed platinum nanoparticles. The current density is estimated from the steady-state polarization curves of anodic oxidation of hydrogen. An analysis of these estimates shows that the amount of platinum required to attain a certain current density with the use of the catalysts prepared according to the proposed technique is one order of magnitude smaller than that with the catalytic layers produced by a traditional activation. [ABSTRACT FROM AUTHOR]

On the basis of the spatial mathematical model of the global carbon dioxide cycle in the biosphere the absorption of carbon dioxide emissions from the fossil fuel burning, deforestation, and soil erosion by terrestrial ecosystems was calculated for all the world and countries of the Central and South America. Effects of deforestation of tropical forests and soil erosion because of inappropriate land use and climate change were calculated until 2060 for countries of the Central and South America.

In this article, two different methods for the detection of enteroviruses in the fresh water were performed and compared. All collected enteroviruses were identified using molecular typing. The possible reasons of water contamination were discussed in conclusions.