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Journal of Earth Science 2014年第1期25卷 1-44页

作者： Yuri D Zakharov alexander m popov Far Eastern Geological Institute Far Eastern BranchRussian Academy of Sciences

After the End-Permian mass extinction, ammonoids reached levels of taxonomic diver- sity higher than in the Changhsingian by the Dienerian Substage of the Induan. However, brachiopods exhibit a prolonged delay in recovery, and their taxonomic diversity had not recovered to Late Permian levels even by the Olenekian. The differential patterns of recovery between these two clades may reflect fundamental differences in physiology and behavior. Brachiopods were benthic organisms that were dependent on specific trophic sources, and their general reduction in size during the Early Triassic may have been a response to a relative paucity of food resources. In contrast, ammonoids were sluggish- nektic organisms that utilized a wider range of trophic sources and that suffered no comparable size decrease during the Early Triassic. Brachiopods may have been at a disadvantage also due to vulner- abilities associated with their larval stage, during which they had to locate a suitable substrate for set- tlement. In contrast, ammonoids had no larval stage and juveniles may have been dispersed widely into favorable habitats. These factors may account for differences in the relative success of ammonoids and brachiopods at high-latitude regions following the End-Permian mass extinction： ammonoids success- fully reeolonized the Boreal region during the Early Triassic whereas brachiopods did not.

关键词： Lower Triassic South Primorye Kazakhstan brachiopod ammonoid biotic recovery.

Nitrogen and Carbon Isotope Data of Olenekian to Anisian Deposits from Kamenushka/South Primorye, Far-Eastern Russia and Their Palaeoenvironmental Significance

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Journal of Earth Science 2018年第4期29卷 837-853页

作者： Yuri D Zakharov micha Horacek alexander m popov Liana G Bondarenko Far Eastern Geological Institute of Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia BLT Wieselburg Research Center HBLFA Francisco-Josephinum Wieselburg 3250 Austria Institute of Lithospheric Research Vienna University Vienna 1090 Austria

The Kamenushka Formation, exposed in the northern part of South Primorye （Kamennshka-1 and Kamenushka-2 sections）, is one of the few localities in the world with richly fossiliferous Lower-Upper Olenekian sedimentary successions. Lower to middle Triassic ammonoid-, brachiopod- and conodont-bearing silty-clayey deposits of the Kamenushka-1 and Kamenushka-2 sections have been isotope-geochemically investigated in detail. As a result, these sections, together with the previously investigated Abrek Section, exposed in the southern part of South Primorye, provide almost complete ^15Non- and ^13Corg- records for the Lower Triassic of this region. Nine N- isotope intervals and the five negative C-isotope excursions, reflecting, apparently, unstable climatic and hydrological conditions, have been distinguished in the Lower Triassic of South Primorye. On the basis of the new C-isotope data the mesohedenstroemia bosphorensis Zone （upper part）, Shimanskyites shimanskyi and Neocolumbites insignis zones of South Primorye are correlated now with the Lower Smithian part of the Yinkeng Formation, the Upper Smithian part of the Helongshan Formation and the middle Spathian part of the Nanlinghu Formation in South China, respectively, as has been observed in the Abrek, Kamenushka-2, West Pingdingshan and majiashan sections.

关键词： Triassic N- and C-isotopes palaeoclimatology bio- and chemostratigraphy Pri- morye Russia.

Unique marine Olenekian-Anisian Boundary Section from South Primorye, Russian Far East

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Journal of China University of Geosciences 2005年第3期16卷 219-230页

作者： Yuri D Zakharov alexander m popov Galina I Buryi Far Eastern Geological Institute Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 RussiaFar Eastern Geological Institute Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia Far Eastern Geological Institute Russian Academy of Sciences (Far Eastern Branch) Stoletiya Prospect 159 Vladivostok 690022 Russia

To show paleontological characteristics of the Olenekian-Anislan boundary beds in the Russian Far East, a review of new data on the Upper Olenekian and Lower Anisian biostratigraphy of South Primorye is given on the basis of five sections： Golyi Cape, Petrovka River, Zhitkov Peninsula, Tchernyschew Bay and Atlasov Cape, using new ammonoid, brachiopod and conodont findings. The most representative ammonoid assemblage at the base of the Anisian was discovered in the Ussuriphyllites amurensis Zone （10.6 m thick） of the Atlasov Cape Section： Parasageceras sp. nov., Prionitidae gen. et sp. nov. , Ussuriphyllites amurensis （Kiparisova）（dominant）, megaphyllites atlasoviensis Zakharov, Leiophyllites praematurus Kiparisova, Leiophyllites sp. , Ussurites sp. , Paradanubites sp. indet., Paracrochordiceras sp. nov., Prohungarites popowi Kiparisova, Arctohungarites primoriensis Zakharov, A. solimani （Toula）, Salterites sp. indet. （gigantic shell）, and Tropigastrites sublachontanus Zakharov. Conodonts Neospathodus cf. homeri （Bender） were found in the lower part of the Ussuriphyllites amurensis Zone of the Atlasov Cape. The Atlasov Cape seems to be one of the very promising sections of the Russian Far East for detailed investigation of the Olenekian-Anisian boundary.

关键词： South Primorye Triassic Olenekian-Anisian boundary ammonoid conodont

New Findings of Latest Early Olenekian(Early Triassic)Fossils in South Primorye,Russian Far East,and Their Stratigraphical Significance

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Journal of Earth Science 2021年第3期32卷 554-572页

作者： Yuri D.Zakharov Liana G.Bondarenko alexander m.popov Olga P.Smyshlyaeva Far Eastern Geological Institute Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russia

Information on latest early Olenekian(latest Smithian)ammonoids is available apparently from only seven regions of the world,including South *** Smithian evidences on this topic are recorded from the West SmID(abbreviation from the Russian name of the quarry:"Building materials and Details"),East SmID and Golyj Cape areas in South *** provides additional information on systematic composition of latest Smithian ammonoid,as well as conodont and brachiopod assemblages from the recently identified Shimanskyites shimanskyi Zone,located between lower Olenekian Anasibirites nevolini Zone and upper Olenekian Tirolites subcassianus *** are many common ammonoid species in the Shimanskyites shimanskyi Zone and the underlying Anasibirites nevolini Zone,e.g.,Prosphingitoides sp.,Arctoceras septentrionale(Diener),Churkites syskoi Zakharov et Shigeta,Submeekoceras?subhhydaspis(Kiparisova),Prionites markevichi Zakharov et Smyshlyaeva,?Anasibirites?simanenkoi Zakharov et Smyshlyaeva,Xenoceltites?subvariocostatus Zakharov et Smyshlyaeva,and mianwaliites zimini Zakharov et *** base of the Shimanskyites shimanskyi Zone,marked by a negativeδ13Corg excursion in the Kamenushka-2 Section by our previous study,coincides with the FO(first occurrence)of ammonoids Shimanskyites shimanskyi Zakharov et Smyshlyaeva and Glyptophiceras ***(Waagen)and conodont Hindeodella budurovi *** zone is characterized additionally by some fossils common for the overlying upper Olenekian Tirolites subcassianus Zone:ammonoids of the genus Kamenushkaites,brachiopods Bittnerihyris margaritovi(Bittner)and Lepismatina *** conodont?Neogondolella?(=?Borinella)jubata *** latest Smithian ammonoids recorded from the Shimanskyites shimanskyi Zone totally consist of 30 taxa belonging to 11 families(Sageceratidae,Ussuiriidae,Aspenitidae,Paranannitidae,Arctoceratidae,Proptychitidae,?Galfetitidae,Prionitidae,?Kashmiritidae,Xenoceltitidae and Palaeophyllitidae).Th

关键词： ammonoids conodonts brachiopods biostratigraphy Smithian Russia

Protective effects of polar lipids and redox-active compounds from marine organisms at modeling of hyperlipidemia and diabetes

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Journal of Biomedical Science and Engineering 2013年第5期6卷 543-550页

作者： alexander m. popov Olga N. Krivoshapko Pacific Institute of Bioorganic Chemistry Far Eastern Branch of Russian Academy of Science Vladivostok Russia

Cardiovascular diseases and diabetes mellitus are leading causes of mortality in modern society. The search for a novel effective remedy represents an important task for modern medicine. A total mixture of phospho- and glycolipids from sea macrophytes Sargassum pallidum, Ulva fenestrata, Zostera marina was separated and the fatty acid composition was determined. The biological activity of the mixtures of polar lipids and natural redox-active compounds (echinochrome A from the flat sea urchin Scaphechinus mirabilis and a polyphenolic complex from the sea grass Zostera marina) was studied under conditions of impairments of carbohydrate and lipid metabolism. Doses and compositions of mixtures of pola lipids and redox-active compounds possessing high corrective activity were optimized in mice with the experimental model of hyperlipidemia and diabetes. Based on these results possible mechanisms of the effects of polar lipids containing various polyunsaturated fatty acids and the investigated redox-active compounds (echinochrome A, rosmarinic acid, luteolin and its sulphate conjugates) have been proposed. The developed compositions may be used for creation of new biologically active additives and remedies.

关键词： PUFA Polyphenols 1 4-Naphtoquinones Diabetes Hyperlipidemia

Campanian Climatic Change:Isotopic Evidence from Far East,North America,North Atlantic and Western Europe

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Acta Geologica Sinica(English Edition) 2007年第6期81卷 1049-1069页

作者： Yuri D. ZAKHAROV Yasunari SHIGETA Kazushige TANABE Yasuhiro IBA Olga P. SmYSHLYAEVA Ekaterina A. SOKOLOVA alexander m. popov Tatiana A. VELIVETSKAYA Tamara B. AFANASYEVA Far Eastern Geological Institute FEB RAS Stoletiya Prospect 159 Vladivostok 690022 Russia Department of Geology National Science Museum 3-23-1 Hyakunincho Shinjuku-ku Tokyo 169-0073 Japan University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan Institute of Oceanology RAS Nakhimovskij Prospect 36 Moscow 117997 Russia

Paleoclimatic settings have been reconstructed for the Campanian using original oxygenisotopic analyses of well-preserved molluskan and foraminifera shells from Russian Far East, Hokkaido, USA, Belgium and some DSDP holes （95, 98, 102, 390A, and 392A） in North Atlantic. Early Early Campanian climatic optimum has been recognized from data on high bottom shelf water paleotemperatures in middle latitudes of both the western circum-Pacific （to 24.2℃） and the eastern circum-Pacific （to 26.4℃） areas and high bottom shallow water paleotemperatures in high latitudes of the Koryak Upland （22.4-25.5℃）, which agrees with the data on the Campanian Barykovskaya flora in high latitudes （Golovneva and Herman, 1998） and Jonker flora and its equivalents in middle latitudes. Judging from the data on comparatively high bottom shallow water paleotemperature values in high latitudes, South Alaska （19.4℃） and the Koryak Upland （22.4-25.5℃）, we also expect Latest Campauian temperature maximum, which has not been confirmed, however, for low and middle latitudes by neither of isotopic nor paleobotanic data now. main dimatic tendency during the Campanian （with the exception of Latest Campanian） has been learned from isotopic composition of Campanian aragonitic ammonoid shells from the Hokkaido-South Sakhalin （Krilyon） marine basin. In contrary to Huber＇s et al. （2002） assumption, we expect warm greenhouse conditions during the most part of the Campanian.

关键词： isotopic data cephalopod bivalve and gastropod mollusks paleotemperatures,Campanian Sakhalin Hokkaido Koryak Upland North America Netherlands Atlantic

Pole to Equator Temperature Gradient for Coniacian Time,Late Cretaceous:Oxygen and Carbon Isotopic Data on the Koryak Upland and Hokkaido

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Journal of Earth Science 2012年第1期23卷 19-32页

作者： Yuri D Zakharov Olga P Smyshlyaeva alexander m popov Tatiana A Velivetskaya Tamara B Afanasyeva Kazushige Tanabe Yasunari Shigeta Haruyoshi maeda Far Eastern Geological Institute Russian Academy of Sciences Far Eastern Branch Geological Institute University of Tokyo Department of Geology National Museum of Nature and Science Department of Earth and Planetary Sciences Graduate School of Science

The purpose of this study was to estimate the Coniacian latitudinal thermal gradient in the Northern Hemisphere. Both hemipelagic （ammonoids） and benthic （brachiopods and bivalves） δ18O and δ^13C records were used. They originated from Coniacian shallow-water sequences across a wide range of paleolatitudes, from the Koryak upland （northern Kamchatka, Russian Far East） in the north, to Hokkaido （Japan） in the south. Among Coniacian ammonoids, both migrants from Hokkaido living in high latitudes （Kamchatka） and endemic forms dwelling in middle-low latitudes （Hokkaido） indicate seemingly close optimal growth temperatures. Nevertheless, certain differences in climatic conditions, prevailing during high-latitude coldest seasons, undoubtedly provoked growth cessation in some groups of ammonites. Our isotopic study suggests latitudinal temperature changes of only 0.12 ℃ per degree of latitude for the Northern Hemisphere in Coniacian times, while the average annual temperature in North Kamchatka seems about 3.3 ℃ lower than that in Hokkaido.

关键词： Coniacian oxygen and carbonisotope paleotemperature Kamchatka Hok-kaido.

microglia:a promising therapeutic target in spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 454-463页

作者： Xiaowei Zha Guoli Zheng Thomas Skutella Karl Kiening Andreas Unterberg alexander Younsi Department of Neurosurgery Heidelberg University HospitalHeidelbergGermany Department of Neuroanatomy Institute for Anatomy and Cell BiologyHeidelberg UniversityHeidelbergGermany

microglia are present throughout the central nervous system and are vital in neural repair,nutrition,phagocytosis,immunological regulation,and maintaining neuronal *** a healthy spinal cord,microglia are accountable for immune surveillance,however,when a spinal cord injury occurs,the microenvironment drastically changes,leading to glial scars and failed axonal *** this context,microglia vary their gene and protein expression during activation,and proliferation in reaction to the injury,influencing injury responses both favorably and unfavorably.A dynamic and multifaceted injury response is mediated by microglia,which interact directly with neurons,astrocytes,oligodendrocytes,and neural stem/progenitor *** a clear understanding of their essential nature and origin,the mechanisms of action and new functions of microglia in spinal cord injury require extensive *** review summarizes current studies on microglial genesis,physiological function,and pathological state,highlights their crucial roles in spinal cord injury,and proposes microglia as a therapeutic target.

关键词： astrocytes cytokines functional recovery immune regulation m1/m2 activation macrophages microglia neuroinflammation spinal cord injury therapy

Reduction of friction by normal *** of contact stiffness

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Friction 2017年第1期5卷 45-55页

作者： m.popov V.L.popov N.V.popov Berlin University of Technology Berlin 10623 GermanyTomsk Polytechnic University Tomsk 634050 RussiaTomsk State University Tomsk 634050 Russia Berlin University of Technology Berlin 10623 Germany

The present paper is devoted to a theoretical analysis of sliding friction under the influence of oscillations perpendicular to the sliding *** contrast to previous works we analyze the influence of the stiffness of the tribological contact in detail and also consider the case of large oscillation amplitudes at which the contact is lost during a part of the oscillation period,so that the sample starts to 'jump'.It is shown that the macroscopic coefficient of friction is a function of only two dimensionless parameters-a dimensionless sliding velocity and dimensionless oscillation *** function in turn depends on the shape of the contacting *** the present paper,analysis is carried out for two shapes:a flat cylindrical punch and a parabolic *** we consider 'stiff systems',where the contact stiffness is small compared with the stiffness of the *** role of the system stiffness will be studied in more detail in a separate paper.

关键词： sliding friction out-of-plane oscillation contact stiffness coefficient of friction active control of friction

Active control of friction by transverse oscillations

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Friction 2019年第1期7卷 74-85页

作者： J.BENAD K.NAKANO V.L.popov m.popov Technische Universit?t Berlin Yokohama National University National Research Tomsk Polytechnic University National Research Tomsk State University

The present paper is devoted to a theoretical analysis of sliding friction under the influence of in-plane oscillations perpendicular to the sliding direction. Contrary to previous studies of this mode of active control of friction, we consider the influence of the stiffness of the tribological contact in detail and show that the contact stiffness plays a central role for small oscillation amplitudes. In the present paper we consider the case of a displacement-controlled system, where the contact stiffness is small compared to the stiffness of the measuring system. It is shown that in this case the macroscopic coefficient of friction is a function of two dimensionless parameters— a dimensionless sliding velocity and dimensionless oscillation amplitude. In the limit of very large oscillation amplitudes, known solutions previously reported in the literature are reproduced. The region of small amplitudes is described for the first time in this paper.

关键词： sliding friction in-plane oscillation contact stiffness coefficient of friction active control of friction