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Inventory of unintentional POPs emission from anthropogenic sources in Antarctica

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Advances in Polar Science 2022年第2期33卷 156-166页

作者： sergey kakareka Tamara KUKHARCHYK Institute for Nature Management National Academy of Sciences of Belarus-Laboratory on Transboundary PollutionSkoriny 10 Minsk 220076Belarus

In spite of remote location and very limited human activities,Antarctica is affected by persistent organic pollutants(POPs).POPs investigation in Antarctica has a comparatively long history,but there are still large knowledge gaps in assessment of their emission into *** the paper the results of the first inventory of unintentional POPs emission from anthropogenic sources in Antarctica for modern period and preliminary estimate for the late 1980s are *** of dioxin/furans(PCDD/Fs)emission in different media,as well as polychlorinated biphenyls(PCBs)and hexachlorobenzene(HCB)in air is based on methodology of emission factors and indicators of human *** following sources of POPs emission have been estimated:power generation and heating,waste incineration,mobile sources and open burning of waste(in the past).According to the data obtained,annual PCDD/Fs air emission for modern period comprises 60.74 mg toxic equivalent(TEQ),PCBs-5.09 mg TEQ,and HCB-457.6 *** 2.5 mg TEQ of dioxin/furans is released to residues,so total PCDD/Fs emission is amounted 63.23 mg *** incineration makes the greatest contribution to POPs emission(96% of PCDD/Fs,98%of PCBs and 36% of HCB air emission).In late 1980s open burning of waste was the major source of *** assessment shows that over a 30-year period air emissions of PCDD/Fs decreased about 13 times,PCBs-15 times and HCB-57 times,primarily due to the prohibition of open burning of waste in compliance with the Protocol on Environmental Protection to the Antarctic Treaty requirements.

关键词： persistent organic pollutants emission inventory PCDD/Fs PCBs HCB

Air pollutants and greenhouse gases emission inventory for power plants in the Antarctic

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Advances in Polar Science 2020年第4期31卷 274-283页

作者： sergey kakareka Institute for Nature Management National Academy of Sciences of Belarus-Laboratory on Transboundary PollutionSkoriny 10 Minsk 220076Belarus

Emissions of air pollutants and greenhouse gases into the atmosphere in Antarctica from power plants with diesel generators(the main sources of energy at Antarctic research stations and the main stationary sources of anthropogenic emissions in the Antarctic)were assessed.A bottom-up approach was used to compile an emission inventory for the *** involved estimating emissions at various spatial levels by sequentially aggregating estimate emissions from point emission *** is the first time this approach has been proposed and *** of CO2,NOx,particulate matter(PM10),and CO in the modern period were estimated at the research station,geographic region,natural domain,biogeographic region,continent section,and whole continent *** emissions are presented here,but the approach allows emissions at different averaging periods to be *** means mean or maximum yearly,monthly,daily,or hourly emissions can be *** estimates could be used to model pollutant transmission and dispersion,assess the impacts of pollutants,and develop emission forecasts for various scenarios.

关键词： air pollutants Antarctica diesel generator emission inventory greenhouse gases station

Chemical composition of natural waters at Broknes Peninsula, Larsemann Hills, Antarctica

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Advances in Polar Science 2023年第4期34卷 318-339页

作者： sergey kakareka Tamara KUKHARCHYK Yury GIGINYAK Peter KURMAN Institute for Nature Management National Academy of Sciences of BelarusLaboratory of Transboundary PollutionMinsk 220076Belarus Scientific and Practical Center for Bioresources National Academy of Sciences of BelarusMinsk 220072Belarus Institute of Bioorganic Chemistry National Academy of Sciences of BelarusLaboratory of Physical and Chemical MethodsMinsk 220141Belarus

The article contributes to the study of the content of major and trace elements in various types of natural waters of the Broknes Peninsula,Larsemann Hills,Antarctica collected in January–February 2014 and 2020 during the 7th and 12th Belarusian Antarctic *** of old(13 samples)and newly fallen snow(5),lakes(23)and groundwater(8)were *** content of 25 major and trace elements was determined using ICP-MS method,main anions was determined by titrimetric and turbidimetric *** similarity chemical composition of snow,groundwater and lake waters in spite of differences in the content of major ions and trace elements has been *** influence of marine salts on natural waters are analyzed,and their accumulation in lake waters especially in the endorheic small and shallow lakes in spite of ultra-oligotrophic atmospheric precipitates are *** spatial heterogeneity of groundwater and temporal and spatial heterogeneity of lake waters have been *** results are important for understanding the variabilities of major and trace elements content in snow,groundwater and lake waters,and their relationship,as well as for identifying trends in their change,taking into account anthropogenic loads in the region and climate change.

关键词： Antarctica snow groundwater lake major element trace element

Open burning of wastes as the source of environmental contamination by POPs

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Chinese Journal Of Geochemistry 2006年第B8期25卷 177-178页

作者： sergey V. kakareka Tamar I. Kukharchyk Institute for Problems of Natural Resources Use & Ecology Minsk Belarus

Heavy metals accumulation in urban soils of Belarus: Testing, mapping and ecological risk assessment

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Chinese Journal Of Geochemistry 2006年第B8期25卷 57-57页

作者： sergey V. kakareka Valery S. Khomich Tamara I. Kukharchyk Institute for Problems of Natural Resources Use & Ecology Minsk Belarus

Radiation of a TM mode from an open end of a three-layer dielectric capillary

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Chinese Physics B 2024年第7期33卷 311-318页

作者： sergey NGalyamin Alexandr MAltmark St.Petersburg State University 7/9Universitetskayanab.St.Petersburg 199034Russia St.Petersburg Electrotechnical University“LETI” 5ProfessoraPopovaSt.Petersburg 197022Russia

Modern trends in beam-driven radiation sources include the interaction of Cherenkov wakefields in open-ended circular waveguides with complicated dielectric linings, with a three-layer dielectric capillary recently proposed to reduce radiation divergence being a representative example [Opt. Lett. 45 5416(2020)]. We present a rigorous approach that allows for an analytical description of the electromagnetic processes that occur when the structure is excited by a single waveguide TM mode. In other words, the corresponding canonical waveguide diffraction problem is solved in a rigorous formulation. This is a continuation of our previous papers which considered simpler cases with a homogeneous or two-layer dielectric filling. Here we use the same analytical approach based on the Wiener–Hopf–Fock technique and deal with the more complicated case of a three-layer dielectric lining. Using the obtained rigorous solution, we discuss the possibility of manipulating the far-field radiation pattern using a third layer made of a low permittivity material.

关键词： diffraction radiation open-ended waveguide Wiener–Hopf technique Cherenkov radiation

Analytical solution of axisymmetric contact problem about indentation of a circular indenter into a soft functionally graded elastic layer

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Acta Mechanica Sinica 2013年第2期29卷 196-201页

作者： sergey Volkov sergey Aizikovich Yue-Sheng Wang Igor Fedotov Research and Education Center "Materials" Don State Technical University South Federal University Research Institute of Mechanics and Applied Mathematics Institute of Engineering Mechanics Beijing Jiaotong University Department of Mathematical Technology Tshwane University of Technology

The paper addresses a contact problem of the theory of elasticity,i.e.,the penetration of a circular indenter with a flat base into a soft functionally graded elastic *** elastic properties of a functionally graded layer arbitrarily vary with depth,and the foundation is assumed to be elastic,yet much harder than a *** analytical solution is constructed,and it is shown that the solutions are asymptotically exact both for large and small values of characteristic dimensionless geometrical parameter of the *** examples are analyzed for the cases of monotonic and nonmonotonic variations of elastic *** results for the case of homogeneous layer are compared with the results for nondeformable foundation.

关键词： Contact problems·Indentation·Functionally graded layer

Updated Kimura-Takemoto classification of atrophic gastritis

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World Journal of Clinical Cases 2021年第13期9卷 3014-3023页

作者： sergey M Kotelevets sergey A Chekh sergey Z Chukov Department of Therapy Medical InstituteNorth Caucasus State Academy for Humanities and TechnologiesCherkessk 369000Russia Department of Software Development Institute of Applied Mathematics and Information TechnologyNorth Caucasus State Academy of Humanities and TechnologiesCherkessk 369000Russia Department of Mathematics Institute of Applied Mathematics and Information TechnologyNorth Caucasus State Academy of Humanities and TechnologiesCherkessk 369000Russia Department of Pathological Anatomy Stavropol State Medical UniversityStavropol 355017Russia

BACKGROUND The Updated Sydney system for visual evaluation of gastric mucosal atrophy viaendoscopic observation is subject to sampling error and interobserver *** Kimura-Takemoto classification system was developed to overcome *** compare the morphological classification of atrophic gastritis between theKimura-Takemoto system and the Updated Sydney *** total of 169 patients with atrophic gastritis were selected according to diagnosisby the visual endoscopic Kimura-Takemoto method. Following the UpdatedKimura-Takemoto classification system, one antrum biopsy and five gastriccorpus biopsies were taken according to the visual stages of the Kimura-Takemoto system. The Updated Kimura-Takemoto classification system was thenapplied to each and showed 165 to have histological mucosal atrophy;theremaining 4 patients had no histological evidence of atrophy in any biopsy. The Updated Kimura-Takemoto classification was verified as a referencemorphological method and applied for the diagnosis of atrophic gastritis. Addingone more biopsy from the antrum to the six biopsies according to the Updated Kimura-Takemoto classification, constitutes the updated combined Kimura-Takemoto classification and Sydney *** sensitivity for degree of mucosal atrophy assessed by the Updated Sydneysystem was 25% for mild, 36% for moderate, and 42% for severe, when comparedwith the Updated Kimura-Takemoto classification of atrophic gastritis formorphological diagnosis. Four types of multifocal atrophic gastritis wereidentified: sequential uniform (type 1;in 28%), sequential non-uniform (type 2;in7%), diffuse uniform (type 3;in 23%), diffuse non-uniform (type 4;in 24%), and"alternating atrophic – non-atrophic" (type 5;in 18%). The pattern of the spread ofatrophy, sequentially from the antrum to the cardiac segment of the stomach,which was described by the Updated Kimura-Takemoto system, washistologically confirmed in 82% of cases ***

关键词： Updated Sydney system Kimura-Takemoto classification Prevention Gastric cancer Atrophic gastritis Morphology

Reactivation of hepatitis B virus infection – an important aspect of multifaceted problem

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World Journal of Gastroenterology 2024年第26期30卷 3193-3197页

作者： sergey Morozov sergey Batskikh Department of Gastroenterology Hepatology and NutritionFederal Research Center of NutritionBiotechnology and Food SafetyMoscow 115446Russia Department of Hepatology Moscow Clinical Scientific Center N.A.A.S.LoginovMoscow 111123Russia

In this editorial we comment on the article published in the recent issue of the W orld Journal of *** focus specifically on the problem of occult hepatitis B virus(HBV)infection,that is a result of previous hepatitis B(PHB)and a source for reactivation of *** prevalence of PHB is underestimated due to the lack of population testing ***,this condition not only com-plicate anticancer treatment,but may be responsible for the development of other diseases,like cancer or autoimmune *** we unveil possible mecha-nisms responsible for realization of these processes and suggest practical approa-ches for diagnosis and treatment.

关键词： Occult hepatitis B virus infection Hepatitis B virus reactivation Previous hepatitis B Cancer Autoimmune disorders