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The Berezitovoe gold-polymetallic deposit(Upper Amur region,Russia)：Structure,mineralogy and genetic aspects

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geoscience Frontiers 2016年第3期7卷 483-494页

作者： Alexandr S. Vakh vadim g. khomich Natalia g. Boriskina M. Santosh far East geological Institute Far East Branch of Russian Academy of Sciences 159 Prospect 100 let Vladivastoku Vladivostok 690022 Russia School of Engineering Far Eastern Federal University 8 Suhanova St. Vladivostok 690950 Russia Department of Earth Sciences University of Adelaide SA 5005 Australia School of Earth Sciences and Resources China University of Geosciences Beijing 29 Xueyuan Road Beijing 100083 China

The Berezitovoe deposit in the Sergachi volcano-plutonic and metallogenic belt preserves evidence for polymetallic mineralization of multiple *** steeply dipping gamet-tourmaline-muscovite-quartz metasomatites（with K-Ar ages of 132 ± 2.9 and 127 ± 4.4 Ma） carry two distinct stages of mineralization developed at different times：（1） polymetallic mineralization and（2） *** deposit is located within Paleozoic gneissose granitoids of the Pikansky complex（dated as 379 ± 1.1 Ma by zircon U-Pb method） intruded by early Cretaceous porphyry-like granites of the Haikta pluton（dated as137 ± 0.67 Ma by zircon U-Pb method） and late Cretaceous dikes of porphyrites,porphyries,and *** suggests the action of late gold-bearing hydrothermal fluids on the early polymetallic ores and the selective mobilization of some elements from these lead to redeposition together with complex sulphosalts.

关键词： Amur River head gold Early Cretaceous Metallogeny Tectonics

Chronology and geochemistry of the Berezitovoe Polymetallic gold Deposit in Eastern Siberia, Russia and its geological Significance

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Acta geologica Sinica(English Edition) 2017年第5期91卷 1733-1750页

作者： ZHANg guobin YANg Yanchen Alexander S.VAKH vadim g. khomich WANg Keyong YE Songqing HAN Shijiong Department of geology Liaoning Technical University College of Earth Sciences Jilin University Far East geological Institute Far East Branch Russian Academy of Sciences

The Berezitovoe deposit is a large-sized Au-Ag-Zn-Pb deposit in the east of the SelengaStanovoi superterrane, Russia. Au-Ag orebodies are hosted by tourmaline-garnet-quartz-muscovite metasomatic rocks; Zn-Pb orebodies are hosted by granodiorites, porphyritic granites and tourmalinegarnet-quartz-muscovite metasomatic rocks. These orebodies are surrounded by wall rocks dominated by the Tukuringra Complex granodiorites, porphyritic granites, and gneissic granodiorites. The alteration includes silicification and garnet, sericitization chloritization, carbonatization and kaollinization. LA-ICP-MS U-Pb zircon dating indicates that the gold mineralization can be divided into two stages in the Berezitovoe polymetallic gold deposit（at 363.5 ± 1.5 Ma, and133.4± 0.5）.Hornblende-plagioclase gneisses of the Mogocha group in the study area underwent Paleoproterozoic metamorphism（at 1870 ± 7.8 and 2400 ± 13 Ma）, gneissic granodiorite of the Tukuringra Complex yields a late Paleozoic magmatic age（at 379.2 ± 1.1 Ma）,and subalkaline porphyritic granitoid of the Amudzhikan Complex yield late Mesozoic magmatic ages（133-139 and 150-163 Ma）. granodiorites of the Tukuringra Complex in the study area have high concentrations of SiO_2（average of 60.9 wt%）, are aluminum-oversaturated（average A/CNK of 1.49）, are enriched in the large ion lithophile elements（e.g.,K, Rb, and Ba）, U, Th, and Pb, are depleted in high field strength elements（e.g., Ta, Nb, and Ti）, and have slightly negative Eu and no Ce anomalies in chondrite-normalized rare earth element *** inclusions from quartz veins include three types： aqueous two-phase, CO2-bearing three-phase,and pure CO2. Aqueous two-phase inclusions homogenize at 167℃-249℃ and have salinities of 4.32%-9.47% NaCl equivalent, densities of 0.86-0.95 g/cm^3, and formed at depths of 0.52-0.94 km. In comparison, the CO2-bearing three-phase inclusions have homogenization temperatures of 265℃-346℃,salinities of 7.14%-11.57% NaCl equivalent, and total

关键词： geochemistry U-Pb zircon dating fluid inclusions Berezitovoe polymetallic gold deposit Eastern Siberia Russia

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

Stepping up after spinal cord injury:negotiating an obstacle during walking

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Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain Frigon Charly g.Lecomte Department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the gait pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

Projective Hilbert modules and sequential approximations

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Science China Mathematics 2025年第1期 137-168页

作者： Lawrence g.Brown Huaxin Lin Department of Mathematics Purdue University Department of Mathematics East China Normal University Department of Mathematics University of Oregon Shanghai Institute for Mathematics and Interdisciplinary Sciences

We show that when A is a separable C*-algebra,every countably generated Hilbert A-module is projective（with bounded module maps as morphisms）.We also study the approximate extensions of bounded module *** the case where A is a σ-unital simple C*-algebra with strict comparison,and every strictly positive lower semicontinuous affine function on quasitraces can be realized as the rank of an element in the Cuntz semigroup,we show that the Cuntz semigroup is equivalent to unitarily equivalent classes of countably generated Hilbert A-modules if and only if A has stable rank one.

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growth of 4＂ diameter polycrystailine diamond wafers with high thermal conductivity by 915 MHz microwave plasma chemical vapor deposition

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Plasma Science and Technology 2017年第3期19卷 93-97页

作者： A F POPOVICH V g RALCHENKO V K BALLA A K MALLIK A A khomich A P BOLSHAKOV D N SOVYK E E ASHKINAZI V Yu YUROV Institute of Radio Engineering and Electronics of Russian Academy of Sciences Fryazino 141190 Russia general Physics Institute of Russian Academy of Sciences Moscow 119991 Russia Harbin Institute of Technology Harbin 150001 People's Republic of China National Research Nuclear University MEPhI Moscow 115409 Russia Central glass and Ceramic Research Institute Kolkata 700 032 India

Polycrystalline diamond（PCD） films 100 mm in diameter are grown by 915 MHz microwave plasma chemical vapor deposition（MPCVD） at different process parameters,and their thermal conductivity（TC） is evaluated by a laser flash technique（LFT） in the temperature range of230-380 *** phase purity and quality of the films are assessed by micro-Raman spectroscopy based on the diamond Raman peak width and the amorphous carbon（a-C） presence in the *** and increasing dependencies for TC with temperature are found for high and low quality samples,***,as high as 1950 ± 230 W m-1 K-1 at room temperature,is measured for the most perfect material.A linear correlation between the TC at room temperature and the fraction of the diamond component in the Raman spectrum for the films is established.

关键词： thermal conductivity polycrystalline diamond microwave plasma chemical vapordeposition Raman spectroscopy

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled Alok Timothy g.White Chunyan Li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa M.g.Cassiano Roney S.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNS)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Deep-seated geodynamics and position of Platinum-bearing basite-ultrabasite massifs of southeast Russia

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global geology 2012年第3期15卷 204-209页

作者： khomich V.g. Boriskina N.g. Far East geological Institute of FEB of Russian Academy of Sciences

In the southeast part of the North-Asian craton, several ring basite-uhrabasite plutons have been rec- ognized, with which the commercial placers of platinoids associate. Analysis of the known geodynamic models of the region formation and materials of seismic tomography showed that the subduction processes, that actively manifested themselves in the Asia-Pacific convergence zone in Mesozoic, were responsible for initiation of the stagnated oceanic slab. Its NE and SW boundaries appear to coincide with the transform faults. Projection of the transform fault, bordering the above mentioned slab in the NEN, coincides with the Konder-Feklistovsky metal- logenic belt distinguished earlier and its Aldan （Inaglinsky） member. Higher platinum content of ring massifs of the belt is controlled by the influence of the lower mantle derivatives on the ascending upper mantle plumes.

关键词： southeast Russia mantle plumes Platinum-bearing ring massifs