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Secondary alteration of minerals in basalts of the Evevpenta gold occurrence(North Kamchatka， Russia) as indicators of ore forming processes

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地学前缘 2023年

作者： Anastasiya Sergeeva Pavel Zhegunov elena skilskaia Mariya Nazarova elena Kartasheva Anna Kuzmina Svetlana Moskaleva Olesya Zobenko Sharapat Kudaeva Ekaterina Plutakhina Kseniya Shishkanova Institute of Volcanology and Seismology， Far Eastern Branch， Russian Academy of Sciences

This paper describes in detail the mineralogy of the propylitic alteration of basalt host rocks in the Evevpenta gold occurrence in North Kamchatka. The vein system of the Evevpenta consists of quartz， adularia-quartz， quartz-carbonate veins， and， hydrothermal breccias hosted in dacite. Vein minerals are native gold， tellurides， sulfides， selenides， Au-Ag chlorides. The propylitic alteration occurs at a distance from the epithermal veins; however， it contains characteristic mineral assemblages useful for the reconstruction of an ore-formation environment. Four distinct hydrothermal alteration assemblages were recognized within the propylitic zone in this study: (1) Fluorapatite-fluorine-aluminous titanite， (2) Quartz-calcite-clinochlore， (3) Quartz-calcite-stilbite-montmorillonite， and 4. Calcite-mordenite. The earliest mineral assemblage was formed from an acid F-enriched hydrothermal fluid. The concentration of fluoride in fluid was 0.2–1.2 g/L， and temperature of about 550 ℃. The long-term interaction between the acid hydrothermal fluid and olivine basalt host rocks resulted in increasing pH to near neutral that caused chloritization process. The chloritization stage hydrothermal fluid was enriched in Fe and Mg with temperatures of about 175–210℃， chlorite I， and 120–140℃， chlorite II. The final stage of alteration consists of zeolite group minerals， which were precipitated from the hydrothermal fluid of pH ～ 9 and temperature >135℃. The high pH of the hydrothermal fluid could be explained by the presence of bicarbonates and carbonates and removal of the iron salt from the solution. Based on the alteration mineral assemblages of the propylitic zone， the physical and chemical conditions of the Evevpenta vein system are discussed. The transport of ore elements took place due to the formation of precious metal Cl–and OH–complexes at the stage of hydrothermal system formation with circulation of alkaline sodium chloride solutions. Chalcogens were also transferred by

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俄罗斯北堪察加Evevpenta金矿床玄武岩矿物次生蚀变特征及其成矿指示作用

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地学前缘 2023年第5期30卷 450-468页

作者： Anastasiya SERGEEVA Pavel ZHEGUNOV elena skilskaia Mariya NAZAROVA elena KARTASHEVA Anna KUZMINA Svetlana MOSKALEVA Olesya ZOBENKO Sharapat KUDAEVA Ekaterina PLUTAKHINA Kseniya SHISHKANOVA Institute of Volcanology and Seismology Far Eastern BranchRussian Academy of SciencesPiip Boulevard9Petropavlovsk-Kamchatsky 683006Russia

俄罗斯北堪察加地区Evevpenta金矿床玄武岩主岩青磐岩化蚀变的矿物学组成,是以英安岩中的石英、冰长石-石英、石英-碳酸岩岩脉和热液角砾岩组成的脉系为特征。脉状矿物是天然金、碲化物、硫化物、硒化物和金-银氯化物。青磐岩化蚀变发... 详细信息

俄罗斯北堪察加地区Evevpenta金矿床玄武岩主岩青磐岩化蚀变的矿物学组成,是以英安岩中的石英、冰长石-石英、石英-碳酸岩岩脉和热液角砾岩组成的脉系为特征。脉状矿物是天然金、碲化物、硫化物、硒化物和金-银氯化物。青磐岩化蚀变发生在距浅成热液脉较远的地方。然而,它的特征矿物组合对重建成矿环境有重要研究意义。在青磐岩化带内可识别出氟磷灰石-氟铝钛矿、石英-方解石-斜绿泥石、石英-方解石-硬石-蒙脱石、方解石-丝光沸石4种不同的热液蚀变组合。最早的矿物组合形成于酸性富F的热液中。热液流体中氟化物浓度为0.2~1.2 g/L,流体温度约550℃。酸性热液与橄榄玄武岩寄主岩石长期相互作用,导致pH升高至接近中性并发生绿泥石化作用。绿泥石化阶段热液富集Fe和Mg,温度约175~210℃时形成第1阶段绿泥石,120~140℃时形成第2阶段绿泥石。蚀变的最后阶段形成沸石群矿物,其在pH约为9、温度>135℃的热液中析出。热液流体的高pH值可能是由于碳酸氢盐和碳酸盐的存在以及溶液中铁盐的去除。根据青磐岩化带蚀变矿物组合特征,探讨了Evevpenta脉系形成的物理化学条件。在热液体系形成阶段,随着碱性氯化钠溶液的循环,贵金属Cl~-和OH~-络合物的形成导致了矿石元素的运移。高pH溶液也能转移硫。

关键词：矿物学金丝光沸石斜绿泥石青磐岩化蚀变 Evevpenta 堪察加

Opinion Dynamics in Two-Layer Networks with Hypocrisy

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Journal of the Operations Research Society of China 2024年第1期12卷 109-132页

作者： Chi Zhao elena Parilina Saint Petersburg State University Saint Petersburg199034Russia Qingdao University School of Mathematics and StatisticsQingdao 266071ShandongChina

We propose a general concealed voter model(GCVM),in which individuals interact in two layers and can exchange their opinions in the internal *** interaction is not allowed in a *** exchanging opinions in the internal layer,we mean that individuals share their real or internal opinions with their close *** process of opinion formation in GCVM is presented in the *** make the series of numerical simulations of GCVM with different network structures(both external and internal)and get some counterintuitive *** instance,we find out that sometimes with a relatively simple network structure of an external layer the consensus within the individuals’opinions cannot be reached,and if individuals in the network are not good at expressing their opinions publicly(in an external layer),exchanging opinions with their close friends(in an internal layer)is almost useless.

关键词： Opinion dynamics Voter model Concealed voter model General concealed voter model

Strong Subgame Consistency of the Core in Stochastic Network Formation Games

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Journal of the Operations Research Society of China 2024年第1期12卷 189-213页

作者： Ping Sun elena Parilina Faculty of Applied Mathematics and Control Processes Saint Petersburg State UniversitySaint Petersburg199034Russia

We consider a model of network formation as a stochastic game with random duration proposed initially in Sun and Parilina(Autom Remote Control 82(6):1065–1082,2021).In the model,the leader first suggests a joint project to other players,i.e.,the network connecting ***,the players are allowed to form fresh links with each other updating the initially proposed *** stage payoff of any player is defined depending on the network *** are two types of randomness in the network formation process:(i)links may fail to be formed with different probabilities although players intend to establish them,(ii)the game process may terminate at any stage or transit to the next stage with a certain probability ***,a network is formed as a result of players’decisions and realization of random *** cooperative version of the stochastic game is *** particular,we examine the properties of subgame consistency as well as strong subgame consistency of the *** provide a payment mechanism or regularization of the core elements to sustain its subgame consistency and avoid the player’s deviations from the cooperative *** addition,the distribution procedure of the core elements is regularized in case there are negative payments to achieve only nonnegative payments to the players at any *** sufficient condition of a strongly subgame consistent core is also *** illustrate our theoretical results with a numerical example.

关键词： Stochastic game Network formation Core Strong subgame consistency

Applying the Shearlet-Based Complexity Measure for Analyzing Mass Transfer in Continuous-Flow Microchannels

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Fluid Dynamics & Materials Processing 2024年第8期20卷 1743-1758页

作者： elena Mosheva Ivan Krasnyakov Institute of Continuous Media Mechanics UB RAS Perm614013Russia Department of Applied Physics Perm National Research Polytechnic UniversityPerm614990Russia

Continuous-flow microchannels are widely employed for synthesizing various materials,including nanoparticles,polymers,and metal-organic frameworks(MOFs),to name a *** technology allows precise control over reaction parameters,resulting in purer,more uniform,and structurally stable products due to more effective mass transfer ***,continuous-flow synthesis processes may be accompanied by the emergence of spatial convective structures initiating convective *** the one hand,convection can accelerate reactions by intensifying mass *** the other hand,it may lead to non-uniformity in the final product or defects,especially in MOF microcrystal *** ability to distinguish regions of convective and diffusive mass transfer may be the key to performing higher-quality reactions and obtaining purer *** this study,we investigate,for the first time,the possibility of using the information complexity measure as a criterion for assessing the intensity of mass transfer in microchannels,considering both spatial and temporal non-uniformities of liquid’s distributions resulting from convection *** calculate the complexity using shearlet transform based on a local *** contrast to existing methods for calculating complexity,the shearlet transform based approach provides a more detailed representation of local *** analysis involves experimental images illustrating the mixing process of two non-reactive liquids in a Y-type continuous-flow microchannel under conditions of double-diffusive convection *** obtained complexity fields characterize the mixing process and structure formation,revealing variations in mass transfer intensity along the *** compare the results with cases of liquid mixing via a pure diffusive *** analysis,it was revealed that the complexity measure exhibits sensitivity to variations in the type of mass transfer,establishing its feasibility as an ind

关键词： Shearlet analysis complexity measure entropy measure convection microchannels double-diffusive instability

Effect of the anionic composition of sulfolane based electrolytes on the performances of lithium-sulfur batteries

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Journal of Energy Chemistry 2024年第8期95卷 231-240,I0005页

作者： elena V.Karaseva elena V.Kuzmina Bo-Quan Li Qiang Zhang Vladimir S.Kolosnitsyn Ufa Institute of Chemistry of the Ufa Federal Research Centre of the Russian Academy of Science 71Prospect OktyabryaUfa 450054BashkortostanRussia Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

In lithium-sulfur batteries,cell design,specifically electrolyte design,has a key impact on the battery *** effect of lithium salt anion donor number(DN)(DN[PF_(6)]^(-)=2.5,DN[N(SO_(2)CF_(3))_(2)]^(-)=5.4,DN[ClO_(4)]^(-)=8.4,DN[SO_(3)CF_(3)]^(-)=16.9,and DN[NO_(3)]^(-)=21.1)on the patterns of lithium-sulfur batteries and lithium metal electrode performances with sulfola ne-based electrolytes is *** increase in DN of lithium salt anions leads to an increase in the depth and rate of electrochemical reduction of sulfur and long-chain lithium polysulfides and to a decrease in those for medium-and short-chain lithium *** of lithium salt anions has weak effect on the discharge capacity of lithium-sulfur batteries and the Coulomb efficiency during cycling,with the exception of LiSO_(3)CF_(3)and LiNO_(3).An increase in DN of lithium salt anions leads to an increase in the cycling duration of lithium metal anodes and to a decrease in the presence of lithium *** sulfolane solutions of LiNO_(3)and LiSO_(3)CF_(3),lithium polysulfides do not affect the cycling duration of lithium metal anodes.

关键词： Donor number Lithium salt Sulfolane Lithium polysulfide Electrolyte Lithium-sulfur battery Lithium metal electrode

SIRT2 as a potential new therapeutic target for Alzheimer's disease

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Neural Regeneration Research 2024年第1期19卷 124-131页

作者： Noemi Sola-Sevilla elena Puerta Department of Pharmacology and Toxicology Faculty of PharmacyUniversity of NavarraNavarra Institute for Health Research(IdiSNA)PamplonaSpain

Alzheimer's disease is the most common cause of dementia globally with an increasing incidence over the years,bringing a heavy burden to individuals and society due to the lack of an effective *** this context,sirtuin 2,the sirtuin with the highest expression in the brain,has emerged as a potential therapeutic target for neurodegenerative *** review summarizes and discusses the complex roles of sirtuin 2 in different molecular mechanisms involved in Alzheimer's disease such as amyloid and tau pathology,microtubule stability,neuroinflammation,myelin formation,autophagy,and oxidative *** role of sirtuin 2 in all these processes highlights its potential implication in the etiology and development of Alzheimer's ***,its presence in different cell types and its enormous variety of substrates leads to apparently contra dictory conclusions when it comes to understanding its specific *** studies in sirtuin 2 research with selective sirtuin2 modulators targeting specific sirtuin 2 substrates are necessary to clarify its specific functions under different conditions and to validate it as a novel pharmacological *** will contribute to the development of new treatment strategies,not only for Alzheimer's disease but also for other neurodegenerative diseases.

关键词： Alzheimer's disease amyloid autophagy memory neurodegenerative diseases neuroinflammation sirtuin 2 tau

How we look:European wild moufon and feral domestic sheep hybrids

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Current Zoology 2024年第3期70卷 298-303页

作者： Nikica Šprem elena Buzan Toni Safner Faculty of Agriculture Department of FisheriesApicultureWildlife Management and Special ZoologyUniversity of ZagrebSvetošimunska cesta 2510000 ZagrebCroatia Faculty of Mathematics Natural Sciences and Information TechnologiesUniversity of PrimorskaGlagoljaška 86000 KoperSlovenia Faculty of Environmental Protection Trg mladosti 73320 VelenjeSlovenia Faculty of Agriculture Department of Plant BreedingGenetics and BiometricsUniversity of ZagrebSvetošimunska cesta 2510000 ZagrebCroatia Centre of Excellence for Biodiversity and Molecular Plant Breeding(CroP-BioDiv) Svetošimunska cesta 2510000 ZagrebCroatia

Hybridization between wild animals and feral individuals from closely related domestic species can occur when they share the same *** events are generally regarded as a threat to the genetic integrity and survival of established wild *** aim of this study is to confrm a hybridization between European moufon and feral sheep on the Adriatic island Dugi Otok,where a group of individuals phenotypically indicative of a possible introgression was *** an ovine medium-density SNP array genotypes,we provided genetic evidence of recent gene admixture between the two *** ADMIXTURE analysis suggests that two hybrid individuals had 82.2%and 94.1%of their ancestry attributable to feral sheep,respectively,with the rest of the moufon in *** analysis estimated the combined probabilities for the putative hybrid individuals belonging to one of the hybrid classes at 87.0%and 90.1%,*** main phenotypic differences in the hybrids were observed in the shape of the horns,a stronger horn circumference than in the moufon and weaker than for the sheep,pronounced horn rings,a shorter tail,and intermediate *** therefore recommend constant monitoring of the purity of the moufon population to maintain its genetic *** addition,all feral sheep should be removed from the wild,and released sheep raised in semi-wild conditions should be better controlled.

关键词： crossbreeding gene introgression livestock Ovis gmelinimusimon SNPs

Outpatient management of obscure gastrointestinal bleeding:A new perspective in high-risk patients

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World Journal of Gastroenterology 2024年第19期30卷 2502-2504页

作者： Maria elena Riccioni Clelia Marmo Digestive Endoscopy Unit Fondazione Policlinico Universitario Agostino GemelliIRCCSUniversitàCattolica del Sacro CuoreLargo Agostino GemelliRome 00168Italy CEMAD Centro Malattie Dell’Apparato Digerente Fondazione Policlinico Universitario Agostino GemelliIRCCSUniversitàCattolica del Sacro CuoreLargo Agostino GemelliRome 00168Italy

Mid-gastrointestinal bleeding accounts for approximately 5%-10%of all gastrointestinal bleeding cases,and vascular lesions represent the most frequent *** rebleeding rate for these lesions is quite high(about 42%).We hereby recommend that scheduled outpatient management of these patients could reduce the risk of rebleeding episodes.

关键词： Gastrointestinal bleeding Small bowel bleeding Recurrent bleeding Rebleeding risk Rebleeding Outpatient management