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Frequency drift rate of solar decameter"drift pair"bursts

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Research in Astronomy and Astrophysics 2017年第9期17卷 101-110页

作者： aleksander Stanislavsky aleksander Konovalenko Yaroslav volvach Institute of Radio Astronomy Kharkiv 61002Ukraine v.N.Karazin Kharkiv National University Kharkiv 61002Ukraine

This paper deals with the detailed analysis of frequency drift rates of solar ＂drift pair＂（DP） bursts observed from 2015 July 10 to 12 during a type III burst storm. The observations were conducted by the UTR-2 radio telescope at 9-33 MHz with high frequency and time resolution. DPs were recorded drifting from higher to lower frequencies （forward DPs） as well as from lower to higher ones （reverse DPs）. Patterns on their dynamic spectrum had various inclines and occupied different bandwidths. The frequency drift rate versus frequency dependence of these bursts has been studied. The fitting model to describe the peak evolution of these bursts in the frequency-time plane is presented. The relationship between DPs and type III solar bursts is discussed.

关键词： Sun: corona -- Sun radio radiation -- methods observational -- techniques spectroscopic

Geomorphological processes and landforms of glacier forelands in the upper Aktru River basin(Gornyi Altai), Russia: evidence for rapid recent retreat and paraglacial adjustment

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Journal of Mountain Science 2020年第4期17卷 824-837页

作者： David W.HEDDING aleksander A.EROFEEv Christel D.HANSEN Alexey v.KHON Zamir R.ABBASOv Department of Geography University of South AfricaJohannesburg 1710South Africa Department of Geography Tomsk State UniversityTomsk 637028Russia Department of Geography Geoinformatics and MeteorologyUniversity of PretoriaPretoria 0002South Africa Institute of Monitoring of Climatic and Ecological Systems(IMCES) Tomsk State UniversityTomsk 637028Russia

The glaciers in the Aktru River basin of Gornyi Altai, Russia currently represent some of the fastest receding glaciers in the world. Formation of the morainic complexes closest to the contemporary glaciers in the Aktru River basin took place during the 17^th-18^th centuries with recession commencing at the end of the 18 th century. Coupled with this glacial retreat, earth surface processes and vegetation succession are responding to shape the glacier forelands. This article presents the first geomorphological maps for the upper reaches of the Aktru River basin and focuses on the geomorphological landforms that occur in the rapidly changing glacier forelands. Geomorphological mapping is difficult in steep mountainous regions and, thus, mapping was completed using satellite imagery, field mapping and observations coupled with highresolution aerial photography obtained from Unmanned Aerial vehicles(UAvs). Critical steps of the procedure used to process UAv imagery and difficulties encountered in this mountainous terrain are noted. The acquired spatial data enable the mapping and classification of small-scale transient geomorphological features such as talus, glacial and glaciofluvial landforms. Their dynamics provide insights into supraglacial and subglacial processes of the glaciers of the Aktru River basin and subsequent paraglacial adjustment. The presented highresolution spatial data, which can also be obtained at high temporal resolutions in the future, can act as a reference frame for geomorphologists and ecologists studying the temporal evolution of glacier forelands of the Aktru River basin during paraglacial adjustment and subsequent colonisation and stabilisation by biota.

关键词： Geomorphology Glacier Forelands Unmanned Aerial vehicle Aktru Altai Russia

Comprehensive semen examination in patients with pancreatic-sufficient and pancreatic-insufficient cystic fibrosis

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Asian Journal of Andrology 2023年第5期25卷 591-597页

作者： Anna O Sedova Maria I Shtaut Elizaveta E Bragina Tatyana M Sorokina Galina v Shmarina Marina v Andreeva Lyubov E Kurilo Stanislav A Krasovskiy aleksander v Polyakov vyacheslav B Chernykh Research Centre for Medical Genetics Russia Moscow 115522

We examined a cohort of 93 cystic fibrosis(CF)male patients who were pancreatic-sufficient(PS-CF;n=40)or pancreatic-insufficient(PI-CF;n=53).Complex semen examination was performed,including standard semen analysis,quantitative karyological analysis(QKA)of immature germ cells(IGCs),transmission electronic microscopy(TEM),biochemical analysis,and sperm DNA fragmentation by terminal deoxynucleotidyl transferase-mediated dUTP nickend labeling(TUNEL)*** was diagnosed in 83(89.2%)*** other 10(10.8%)patients were found to be nonazoospermic and showed various spermatological diagnoses(asthenozoospermia,n=2;asthenoteratozoospermia,n=3;oligoasthenozoospermia,n=1;oligoasthenoteratozoospermia,n=3;and normozoospermia,n=1)with no specific morphological *** was detected in 89.2%azoospermic and 30.0%nonazoospermic *** seminal pH(vealed in 2.4%azoospermic and 40.0%nonazoospermic semen *** signs of partial meiotic arrest at prophase I were found in 4 of 6 nonazoospermic patients examined by QKA of *** content of fructose and citrate was low in oligospermic and normal in nonoligospermic semen *** increased percentage(>30%)of spermatozoa with noncondensed(“immature”)chromatin was revealed in 2 of 6 nonazoospermic semen samples analyzed by TEM.

关键词： congenital bilateral agenesia/aplasia of vas deferens cystic fibrosis cystic fibrosis transmembrane conductance regulator gene semen spermatozoa

Genesis of pyroxenite veins in supra-subduction zone peridotites:Evidence from petrography and mineral composition of Egiingol massif(Northern Mongolia)

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China Geology 2020年第2期3卷 299-313页

作者： Anas A.Karimov Marina A.Gornova vasiliy A.Belyaev aleksander Ya.Medvedev Nikolay v.Bryanskiy A.P.vinogradov Institute of Geochemistry Siberian Branch of Russian Academy of Sciences IrkutskFavorskogo str.1A 664033Russia

Swarms of orthopyroxenite and websterite veins are found within Egiingol residual SSZ peridotite massif of Dzhida terrain(Central Asian Orogenic Belt,Northern Mongolia).The process of Egiingol pyroxenite veins formation is investigated using new major and trace element analyses of pyroxenite minerals,calculations of closure temperatures and composition of equilibrium *** pyroxenites show abundant petrographic and geochemical evidence for replacement of the residual peridotite minerals by ortho-and clinopyroxene due to melt-rock *** of peridotite olivines are found in pyroxenites,Cr#of spinel increases from peridotites to pyroxenites,and compositions of ortho-and clinopyroxene change from peridotite to *** authors show that calculated equilibrium melts for investigated pyroxenites are very similar to compositions of boninite lavas from the Dzhida ***,formation of pyroxenite veins most likely resulted from percolation of boninite melts through the Egiingol *** veins formed at first,followed by websterite ***,the authors assume that pyroxenite veins represent the channels for boninitic melts migration in supra-subduction environment.

关键词： Pyroxenite vein Boninite Partial melting Melt-rock interaction Supra-subduction zone peridotite Egiingol massif Dzhida terrain Central Asian Orogenic Belt Northern Mongolia

Enabling rapid X-ray CT characterisation for additive manufacturing using CAD models and deep learning-based reconstruction

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npj Computational Materials 2023年第1期9卷 1443-1452页

作者： Amirkoushyar Ziabari S.v.venkatakrishnan Zackary Snow aleksander Lisovich Michael Sprayberry Paul Brackman Curtis Frederick Pradeep Bhattad Sarah Graham Philip Bingham Ryan Dehoff Alex Plotkowski vincent Paquit Energy and Electrification Infrastructure Division Oak Ridge National LaboratoryKnoxvilleTN 37830USA ZEISS Industrial Metrology LLC Maple GroveMN 55369USA Manufacturing Science Division Oak Ridge National LaboratoryOak RidgeTNUSA Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTNUSA

Metal additive manufacturing(AM)offers flexibility and cost-effectiveness for printing complex parts but is limited to few *** new alloys requires process parameter optimisation to produce consistent,high-quality ***-resolution X-ray computed tomography(XCT)has not been effective for this task due to artifacts,slow scan speed,and *** propose a deep learning-based approach for rapid XCT acquisition and reconstruction of metal AM parts,leveraging computer-aided design models and physics-based simulations of nonlinear interactions between X-ray radiation and *** significantly reduces beam hardening and common XCT *** demonstrate high-throughput characterisation of over a hundred AlCe alloy components,quantifying improvements in characterisation time and quality compared to high-resolution microscopy and *** approach facilitates investigating the impact of process parameters and their geometry dependence in metal AM.

关键词： rapid alloy character

Changes in the Structure and Properties of the Cu-Pb Composites Interface Jointed in the Solid Phase

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Open Journal of Metal 2018年第3期8卷 55-65页

作者： Boris v. Borts aleksander A. Parkhomenko Igor A. vorobiev aleksander A. Lopata vitaliy A. Aleksandrov Michael P. Domnich National Science Center “Kharkov Institute of Physics and Technology” Kharkov Ukraine

Research of structure and properties of Cu-Pb-Cu composite interface, obtained by technology of pack rolling of the pair of mutually insoluble metals, was performed using the methods of metallography, micro- and nano-hardness, mechanical tests, energy-dispersion elementary analyses. The work was aimed at the analyses of possible mechanical mechanisms of mass-transfer, determining the hardness of metal joint in conditions of absence of inter-diffusion. It was shown that different intensity of mass transfer of copper and lead takes place through the composite interface, which corresponds to the results obtained on the other system of dissimilar materials—copper-niobium. Qualitative explanation of these patterns was offered on the basis of more intensive plastic flow of fusible compound of the composite in conditions of roll-bond joining.

关键词： Solid State Joint Cu-Pb Composite Deformation Mass Transfer Interface

Wave Processes and Mass Transfer on the Copper-Stainless Steel Interface under Solid Phase Bonding by High-Temperature Rolling

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Open Journal of Metal 2018年第4期8卷 67-74页

作者： Boris v. Borts aleksander A. Parkhomenko Igor O. vorobyov Alexander A. Lopata National Science Center Kharkov Institute of Physics & Technology Kharkov Ukraine

The paper presents the study of hierarchy of deformation wave-processes from nano- to macro-structural level, which takes place in dissimilar materials, bonded by high-temperature vacuum rolling in solid phase. The focus was on the processes that occur on the interface of the bonded materials: mass trasfer of impurities and alloying elements stimulated by deformation, the study of nano- and micro-hardness.

关键词： vacuum Hot Rolling Solid Phase Interface Cupper-Stainless Steel Microscopy Micro-Hardness Nano-Hardness Wave Processes Scaling

Study on Operation of Arctic Offshore Complex by Means of Multicomponent Process-Based Simulation

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Journal of Marine Science and Application 2018年第4期17卷 471-497页

作者： Oleg v.Tarovik Alex Topaj Andrey B.Krestyantsev aleksander A.Kondratenko Dmitry A.Zaikin Krylov State Research Centre St.Petersburg 196158Russia Gazprom Neft Shelf LLC St.Petersburg 197198Russia

We developed a detailed simulation model of the Arctic marine transport system(MTS) for oil platform Prirazlomnaya. The model has a multidisciplinary nature and involves: sub-models of various transport and technological processes; stochastic weather generator to obtain time series of 15 environmental parameters; and contextual planning algorithm to build voyage plan considering several types of ships and cargoes. We used a significant amount of real operational data to identify model parameters and to prove its statistical reliability. Our main scientific task is to investigate the interaction of various processes of a different nature, while the practical aim is to find a set of measures to increase the efficiency of MTS. The results of the study reveal many examples of the mutual interaction of various processes that need to be considered at the design stage to avoid technical *** study formed a basis for making managerial decisions at the top level of Gazprom Neft Shelf Company.

关键词： Marine transport system Discrete event simulation Offshore oil platform Stochastic weather generator vessel voyage planning Supply vessels operation Arctic tankers

Folate and vitamin B12 in idiopathic male infertility

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Asian Journal of Andrology 2011年第6期13卷 856-861页

作者： Laurel E Murphy James L Mills Anne M Molloy Cong Qian Tonia C Carter Helena Strevens Dag Wide-Swensson aleksander Giwercman Richard J Levine Division of Epidemiology Statistics and Prevention Research Eunice Kennedy Shriver National Institute of Child Health and Human Development Bethesda MD 20892 USA School of Medicine Trinity College Dublin Dublin Ireland Glotech Inc Rockville MD 20850 USA Department of Obstetrics and Gynecology Sk~ne University Hospital in Lund Lund University S-221 85 Lund Sweden Reproductive Medicine Centre Skane University Hospital Maimo Lund University S-205 02 Malmo Sweden

Although methylenetetrahydrofolate reductase, a folate enzyme gene, has been associated with idiopathic male infertility, few studies have examined other folate-related metabolites and genes. We investigated whether idiopathic male infertility is associated with variants in folate, vitamin B12 （B12） and total homocysteine （tHcy）-related genes and measured these metabolites in blood. We conducted a case-control study that included 153 men with idiopathic infertility and 184 fertile male controls recruited at the Fertility Center and Antenatal Care Center, University Hospital, Malmo and Lund, Sweden. Serum folate, red cell folate （RCF）, serum B12, plasma tHcy and semen quality were measured. Subjects were genotyped for 20 common variants in 12 genes related to folate/B12/ homocysteine metabolism. Metabolite concentrations and genotype distributions were compared between cases and controls using linear and logistic regression with adjustment for covariates. The phosphatidylethanolamine N-methyltransferase （PEMT） M 175v and TCblR rs173665 polymorphisms were significantly associated with infertility （P=0.01 and P=0.009, respectively）, but not with semen quality. Among non-users of supplements, infertile men had lower serum folate concentrations than fertile men （12.89 vs. 14.73 nmoll^- 1 P=0.02）, but there were no significant differences in RCF, B 12 or tHcy. Folate, B 12 and tHcy concentrations were not correlated with any semen parameters. This study provides little support for low folate or B12 status in the pathogenesis of idiopathic male infertility. Although additional data are needed to confirm these initial findings, our results suggest that PEMTand TCbIR, genes involved in choline and B12 metabolism, merit further investigation in idiopathic male infertility.

关键词： folate idiopathic male infertility semen quality vitamin B12