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37ka以来日本海沉积物有机质碳和氮稳定同位素变化及其古海洋学意义

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地学前缘 2022年第4期29卷 123-135页

作者：邹建军宗娴朱爱美豆汝席林锦辉冯旭光董智 sergey a.gorbarenko 郑立伟石学法自然资源部第一海洋研究所海洋地质与成矿作用重点实验室山东青岛266061 青岛海洋科学与技术试点国家实验室海洋地质过程与环境功能实验室山东青岛266237 俄罗斯科学院远东分院太平洋海洋研究所俄罗斯符拉迪沃斯托克690041 海南大学南海海洋资源利用国家重点实验室海南海口570000

海洋沉积物有机质碳氮稳定同位素(δ^(13)C、δ^(15)N)广泛用于有机质来源示踪、古生产力和古海洋环境重建。日本海沉积物δ^(13)C和δ^(15)N值一个显著特征是在末次冰盛期(LGM)同步负偏,但是对这一现象产生的原因以及他们的演化过程的... 详细信息

海洋沉积物有机质碳氮稳定同位素(δ^(13)C、δ^(15)N)广泛用于有机质来源示踪、古生产力和古海洋环境重建。日本海沉积物δ^(13)C和δ^(15)N值一个显著特征是在末次冰盛期(LGM)同步负偏,但是对这一现象产生的原因以及他们的演化过程的认识仍然存在明显不足。在本研究中,我们详细调查了37 ka以来日本海中部LV53-23-1岩心沉积物δ^(13)C和δ^(15)N演化历史。结果显示,沉积物δ^(13)C和δ^(15)N分别介于-26.3‰至-22.5‰和1.6‰至6.1‰,低值出现在LGM(26.5~17 ka)暗色层状泥发育时期,指示较强的陆源输入贡献。在Heinrich冰阶1时期(17~14.5 ka),δ^(13)C和δ^(15)N快速正偏,表明日本海海洋环境发生了明显的转换,对应于对马海峡淹没及对马暖流入侵。14.5 ka之后,沉积物δ^(15)N值恢复到5‰,与开阔大洋海水硝酸盐的δ^(15)N值近似。我们采用二端员混合模型粗略地估算了有机质来源的相对贡献。LGM时期陆源有机质贡献介于65%至80%,14.5 ka以后海源有机质贡献介于60%至80%。除了增加的陆源有机质贡献以外,LGM时期沉积物δ^(15)N亏损还涉及如下过程:(1)较高的含Fe沙尘供给提高日本海表层海洋生物固氮效率;(2)缺氧环境盛行减弱成岩作用对沉积物δ^(15)N影响。37 ka以来,日本海沉积物δ^(13)C和δ^(15)N变化与有机质来源、营养盐的供给、表层生产力和沉积物氧化还原条件相关,实际受海平面和全球气候制约。

关键词：碳氮稳定同位素沉积物有机质来源海平面末次冰期日本海

Do non-dipole geomagnetic field behaviors persistently exist in the subarctic Pacific Ocean over the past 140 ka?

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Science Bulletin 2020年第18期65卷 1505-1507,M0003页

作者： Yi Zhong Yanguang Liu Xiaoqiang Yang Jian Zhang Jiabo Liu Aleksandr Bosin sergey a.gorbarenko Xuefa Shi Ting Chen Yu-Min Chou Wei Liu Haosen Wang Congcong Gai Jianxing Liu Alexander NDerkachev Xiaoke Qiang Qingsong Liu Centre for Marine Magnetism Department of Ocean Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China Key Laboratory of Marine Sedimentology and Metallogeny First Institute of OceanographyMinistry of Natural ResoursesQingdao 266061China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266061China Department of Earth Science Sun Yat-sen UniversityGuangzhou 510275China Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijing 100049China V.I.Il'ichev Pacific Oceanological Institute Far East Branch of Russian Academy of ScienceVladivostok 690041Russia State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Research School of Earth Sciences Australian National UniversityCanberra ACT 2601Australia State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China

Paleomagnetic records from globally distributed locations are essential for fully understanding geomagnetic field variations,particularly non-dipole field fluctuations[1].Paleomagnetic studies on historical time scales have demonstrated the existence of persistent geomagnetic flux patches,such as the Canadian(North America)and Siberian(East Asia)flux lobes,which may result from an organizing structure imposed on the geomagnetic field by lower mantle heterogeneity[2].Holocene paleomagnetic secular variations,reconstructed from the Alaskan margin of the Subarctic Pacific Ocean(SPO)[3]and revealed by dynamo modeling[4],further suggest that time-varying flux expulsions on the core-mantle boundary recurrently occur in high-latitude locations(***).

关键词： geomagnetic mantle Holocene

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

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

A Note on Transition Kernels for the Most UnfavourableMixed Strategies of the Market

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Journal of the Operations Research Society of China 2024年第1期12卷 35-50页

作者： sergey N.Smirnov Faculty of Computational Mathematics and Cybernetics Lomonosov Moscow State UniversityMoscowRussian Federation 119991

We consider a deterministic model of market evolution with trading constraints andapply a game-theoretic approach to the superhedging *** obtain sufﬁcientconditions for the game equilibrium and prove under these conditions the existenceof a Borel-measurable transition kernel describing dependence on price prehistory ofthe most unfavourable mixed strategy of the market.

关键词： Superhedging Guaranteed deterministic approach Optimal mixedstrategies of the market Borel-measurable transition kernel Game equilibrium

Structural Stability of the Financial Market Model: Continuity of Superhedging Price and Model Approximation

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Journal of the Operations Research Society of China 2024年第1期12卷 215-241页

作者： sergey N.Smirnov Faculty of Computational Mathematics and Cybernetics Lomonosov Moscow State UniversityMoscow119991Russian Federation

The present paper continues the topic of our recent paper in the same journal,aiming to show the role of structural stability in financial *** the context of financial market modeling,structural stability means that a specific“no-arbitrage”property is unaffected by small(with respect to the Pompeiu–Hausdorff metric)perturbations of the model’s *** formulate,based on our economic interpretation,a new requirement concerning“no arbitrage”properties,which we call the“uncertainty principle”.This principle in the case of no-trading constraints is equivalent to structural *** demonstrate that structural stability is essential for a correct model approximation(which is used in our numerical method for superhedging price computation).We also show that structural stability is important for the continuity of superhedging prices and discuss the sufficient conditions for this continuity.

关键词： Uncertainty Structural stability No arbitrage Continuity of superhedging price Compact-valued multifunction Financial market model approximation Trading constraints

Unveiling the early universe:Axion-like particles and their role in primordial structure formation

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 178-179页

作者： sergey G.Rubin National Research Nuclear University MEPhI(Moscow Engineering Physics Institute) Moscow 115409Russia

The groundbreaking discovery of gravitational waves(GWs)by the LIGO-VIRGO-KAGRO collaboration has revolutionized our understanding of the universe and opened up a new way of observing cosmic events. Unlike light waves... 详细信息

关键词： universe gravitational cosmic

Analysis of natural vibration of truncated conical shells partially filled with fluid

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International Journal of Mechanical System Dynamics 2024年第2期4卷 142-152页

作者： sergey A.Bochkarev sergey V.Lekomtsev Laboratory of Functional Materials Institute of Continuous Media MechanicsUral Branch of Russian Academy of SciencesPermRussian Federation

In this paper,we study the vibrational behavior of shells in the form of truncated cones containing an ideal compressible *** sloshing effect on the free surface of the fluid is *** dynamic behavior of the elastic structure is investigated based on the classical shell theory,the constitutive relations of which represent a system of ordinary differential equations written for new *** fluid vibrations are described in terms of acoustic approximation using the wave equation for hydrodynamic pressure written in spherical *** transformation into the system of ordinary differential equations is carried out by applying the generalized differential quadrature *** formulated boundary value problem is solved by Godunov's orthogonal sweep *** frequencies of shell vibrations are calculated using the stepwise procedure and the Muller *** accuracy and reliability of the obtained results are estimated by making a comparison with the known numerical and analytical *** dependencies of the lowest frequency on the fluid level and cone angle of shells under different combinations of boundary conditions(simply supported,rigidly clamped,and cantilevered shells)have been studied *** conical straight and inverted shells,a numerical analysis has been performed to estimate the possibility of finding configurations at which the lowest natural frequencies exceed the corresponding values of the equivalent cylindrical shell.

关键词： classical shell theory conical shell Godunov's orthogonal sweep method ideal compressible fluid generalized differential quadrature method natural vibrations

A Review on Characteristics, Extraction Methods and Applications of Renewable Insect Protein

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Journal of Renewable Materials 2024年第5期12卷 923-950页

作者： Adelya Khayrova sergey Lopatin Valery Varlamov Research Centre of Biotechnology of the Russian Academy of Sciences Moscow119071Russia

Due to the expected rise in the world population,an increase in the requirements for quality and safety of food and feed is expected,which leads to the growing demand for new sources of sustainable and renewable *** protein is gaining importance as a renewable material for several reasons,reﬂecting its potential contribu-tions to sustainability,resource efﬁciency,and environmental *** insect species are known to be able to efﬁciently convert organic waste into high-value products such as protein,requiring less land and water compared to traditional *** addition,insect farming produces fewer greenhouse gas emissions,contri-buting to mitigating climate *** are considered as a major potential alternative to animal or plant protein due to their many nutritional beneﬁts,including high protein,mineral,and vitamin *** average,the protein content of insects ranges between 35%and 60%dry weight,which exceeds plant protein sources,such as cereal,soybeans,and *** the acceptance of insect protein grows and technologies advance,the food and feed industries continue to explore and expand their applications,offering consumers diverse and sustainable pro-tein *** this review,we discuss the recentﬁndings relating to insect protein focusing on its characteristics,extraction methods,applications,and opportunities along with some trade-offs and uncertainties.

关键词： Circular economy waste utilisation protein insect Hermetia illucens