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中亚造山带中斑岩铜钼矿的Re,Pt,Pd和Au含量

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岩石学报 2007年第8期23卷 1957-1972页

作者： Anita N.Berzina alexander f.Korobeinikov Institute of Geology and Mineralogy Koptyug Avenue3Novosibirsk 630090Russia Tomsk Polytechnic University Lenin Avenue30Tomsk 634050Russia

Precious metal(Pt,Pd and Au)and Re contents in rocks,ores and flotation concentrates of Siberian(Russia)andMongolian porphyry Cu-Mo and Mo-Cu deposits were *** following deposits are discussed:Early Devonian porphyry Mo-CuSora deposit(Kuznetsk Alatau Mountains,Russia)and porphyry Cu-Mo Aksug deposit,(northeastern Tuva,Russia);Triassicporphyry Cu-Mo Erdenetiin Ovoo deposit(northern Mongolia).The samples analyzed include unaltered host rocks of plutons,porphyryrocks of ore-bearing series,different types of altered rocks,mineral separate analyses of molybdenite,chalcopyrite and magnetite,aswell as flotation ***,Pd,Au and Re contents were determined using ICP/MS,AAS and inversion voltammetric *** abundances in rocks and poorly mineralized samples span a large range from below detection limit to 65 ppb Pt and 74 *** concentrations in whole rock samples range from below detection limit to 89 *** has been shown to be the majorhost phase for *** results presented show that Aksug deposit reveals elevated PGE and Au contents in ore minerals and *** Pd contents in ores of the Aksug deposit are in accordance with the presence of palladium mineralization in the formof palladium telluride merenskyite(Pd,Pt)Te_*** variety of precious metals and Re contents in the studied deposits could be caused by a complex interplay of several factors,including importance of primary metal concentrations derived from the source,transport of metals to the deposition area,physicochemical properties of the fluid(fo_2,pH,fs,T,P),and depositional *** Re contents in molybdenite andchalcopyrite separates are typical for copper-rich Aksug and Erdenetiin Ovoo *** concentration in sulfides frommolybdenum-rich Sora deposit is significantly *** oxidized,Cl-rich fluid style at Aksug and Erdenetiin Ovoo was favorable forhigh rhenium solubility and transport to depositional *** occurrence of signif

关键词：铼铂族元素斑岩铜钼矿床 Aksug Sora Erdenetiin Ovoo

Cell surface engineering with polyelectrolyte-stabilized magnetic nanoparticles： A facile approach for fabrication of artificial multicellular tissue-mimicking clusters

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Nano Research 2015年第8期8卷 2515-2532页

作者： Maria R. Dzamukova Ekaterina A. Naumenko Elvira V. Rozhina alexander A. Trifonov Rawil f. fakhrullin Bionanotechnology Lab Institute of Fundamental Medicine and Biology Kazan Federal University Kreml uraml 18 Kazan 420008Republic of Tatarstan Russian Federation

Regenerative medicine requires new ways to assemble and manipulate cells for fabrication of tissue-like constructs. Here we report a novel approach for cell surface engineering of human cells using polymer-stabilized magnetic nanoparticles （MNPs）. Cationic polyelectrolyte-coated MNPs are directly deposited onto cellular membranes, producing a mesoporous semi-permeable layer and rendering cells magnetically responsive. Deposition of MNPs can be completed within minutes, under cell-friendly conditions （room temperature and physiologic media）. Microscopy （TEM, SEM, AfM, and enhanced dark-field imaging） revealed the intercalation of nanoparticles into the cellular microvilli network. A detailed viability investigation was performed and suggested that MNPs do not inhibit membrane integrity, enzymatic activity, adhesion, proliferation, or cytoskeleton formation, and do not induce apoptosis in either cancer or primary cells. finally, magnetically functionalized cells were employed to fabricate viable layered planar （two-cell layers） cell sheets and 3D multicellular spheroids.

关键词： magnetic nanoparticles artificial multicelluar clusters magnetic modification

Closed cranial window rodent model for investigating hemodynamic response to elevated intracranial pressure

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Animal Models and Experimental Medicine 2021年第4期4卷 391-397页

作者： Matt T.Oberdier James f.Antaki alexander Kharlamov Stephen C.Jones Department of Biomedical Engineering Carnegie Mellon UniversityPittsburghPennsylvaniaUSA Department of Anesthesiology Allegheny-Singer Research InstitutePittsburghPennsylvaniaUSA

Background:Elevated intracranial pressure(ICP)occurs in several physiological and pathological conditions,yet long-term sequellae are not common,which implies that blood flow is preserved above ischemic ***:This pilot study sought to confirm this hypothesis using a closed cranial window model in a rat in which ICP was elevated to 120 mmHg for 12 min,and superficial cortical perfusion was measured by laser Doppler flowmetry and laser speckle ***:following a transient increase,cortical blood flow decreased to between 25%and 75%of *** levels correspond to disrupted metabolism and decreased protein synthesis but did not exceed thresholds for electrical signaling or membrane *** may partially explain how some episodes of elevated ICP remain ***:The closed cranial window model provides a platform for prospective study of physiologic responses to artificially elevated ICP during neurosurgery to promote hemostasis.

关键词： cerebrovascular circulation craniotomy hemodynamics hydrocephalus intracranial pressure perfusion

New characterizations of finite supersoluble groups

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Science China Mathematics 2008年第5期51卷 827-841页

作者： alexander N SKIBA Department of Mathematics Gomel State University of f.Skorina

Let A be a subgroup of a group G and X a nonempty subset of G. A is called an X-semipermutable subgroup of G if A has a supplement T in G such that for every subgroup T 1 of T there exists an element x ∈ X such that ... 详细信息

关键词： finite groups supplement 2-maximal subgroups X-semipermutable supersoluble groups 20D10

The Torsind—A Device Based on a New Principle for Non-Conventional Astronomical Observations

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International Journal of Astronomy and Astrophysics 2013年第2期3卷 33-38页

作者： alexander f. Pugach Main Astronomical Observatory of National Academy of Sciences Kiev Ukraine

The description of a new device which is an improved version of the classic torsion balance is given. The device, which is the so-called “torsind”, seemed to be very sensitive to solar/lunar eclipses, and a Venus transit. It even responded to a solar eclipse when installed underground. The results of the most well-documented cases are described.

关键词： Solar Lunar Eclipses Venus Transit Torsion Balance Torsind

SAS and SSA Conditions for Congruent Triangles

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Journal of Mathematics and System Science 2018年第2期8卷 59-66页

作者： alexander f.Mironychev Challenge Early College HS 5801 West Loop South FreewayHoustonTX 77081USA

for two triangles to be congruent,SAS theorem requires two sides and the included angle of the first triangle to be congruent to the corresponding two sides and included angle of the second *** the congruent angles are not between the corresponding congruent sides,then such triangles could be *** turns out that it is possible to describe four cases in which triangles are congruent even though congruent *** two triangles to be congruent,SAS theorem requires two sides and the included angle of the first triangle to be congruent to the corresponding two sides and included angle of the second *** the congruent angles are not between the corresponding congruent sides,then such triangles could be *** turns out that it is possible to describe four cases in which triangles are congruent even though congruent angles are not between the corresponding congruent *** a theorem could be named,for example,SSA *** texts state that two triangles cannot be shown to be congruent if the condition of SSA ***,the author describes cases in which such triangles could be proven congruent with the SSA *** immediate consequence of this new understanding is the necessity of revising many problems and answers in high school and college-level texts related to congruent *** not between the corresponding congruent *** a theorem could be named,for example,SSA *** immediate consequence of this new understanding is the necessity of revising many problems and answers in high school and college-level texts related to congruent triangles.

关键词： Congruent triangles a theorem a proof superposition SAS and SSA conditions

Exact Singularity Subtraction from Boundary Integral Equations in Modeling Vesicles and Red Blood Cells

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Numerical Mathematics(Theory,Methods and Applications) 2014年第4期7卷 413-434页

作者： alexander farutin Chaouqi Misbah UniversitéGrenoble I/CNRS Laboratoire Interdisciplinaire de Physique/UMR5588Grenoble F-38041France

The study of vesicles,capsules and red blood cells(RBCs)under flow is a field of active research,belonging to the general problematic of fluid/structure ***,we are interested in modeling vesicles,capsules and RBCs using a boundary integral formulation,and focus on exact singularity subtractions of the kernel of the integral equations in *** order to increase the precision of singular and near-singular integration,we propose here a refinement procedure in the vicinity of the pole of the Green-Oseen *** refinement is performed homogeneously everywhere on the source surface in order to reuse the additional quadrature nodes when calculating boundary integrals in multiple target *** also introduce a multi-level look-up algorithm in order to select the additional quadrature nodes in vicinity of the pole of the Green-Oseen *** expected convergence rate of the proposed algorithm is of order δ(1/N^(2))while the computational complexity is of order δ(N^(2) lnN),where N is the number of degrees of freedom used for surface *** numerical tests are presented to demonstrate the convergence and the efficiency of the method.

关键词： Stokes flow fluid structure interaction boundary integral method red blood cells singularity subtraction

On the Analytical Models of Protoplanetary formation in Extrasolar Systems

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Space(Science & Technology) 2022年第1期2022卷 422-440页

作者： alexander M.Krot Laboratory of Self-Organization System Modeling United Institute of Informatics ProblemsNational Academy of Sciences of Belarus6Surganov Str.220012 MinskBelarus

In this work,we consider a statistical theory for a cosmogonical body formation(so-called spheroidal body)to develop the analytical models of protoplanetary formation in extrasolar *** the framework of this theory,the models and evolution equations of the statistical mechanics have been proposed,while the well-known problem of gravitational condensation of infinite distributed cosmic substances has been *** paper derives the general equation of distribution of the specific angular momentum of forming protoplanets since the specific angular momentums(for particles or planetesimals)are averaged during a conglomeration process(under a planetary embryo formation).As a result,a new law for planetary distances(which generalizes Schmidt’s law)is derived *** paper develops also an alternative thermal emission of particles model of the formation of protoplanets in extrasolar *** the framework of this model,the equation for the thermal distribution function of the specific angular momentums of particles moving in elliptical orbits in the gravitational field is *** to this thermal escape model,only 0.8%of the total number of particles in the solar system composing the protoplanetary cloud has angular momentum 15.6 times higher than the angular momentum of the remaining 99%of *** conclusion agrees completely with the known fact of a nonuniform distribution of the angular momentums in our solar system noted by ter *** pointed out here,the exponential laws of planetary distances occur in some extrasolar systems.

关键词： momentum angular equation

Turning up the NAD^(+)-mitophagy axis to treat Alzheimer's disease

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Neural Regeneration Research 2023年第2期18卷 319-319页

作者： Evandro f.fang alexander Anisimov Department of Clinical Molecular Biology University of Oslo and Akershus University HospitalLørenskogNorway The Norwegian Centre on Healthy Ageing(NO-Age) OsloNorway

The increase in the prevalence of individuals with Alzheimer's disease(AD)combined with the lack of a cure calls for the development of novel therapies against AD(Canter et al.,2016).The key disease-defining pathological features of AD are the accumulation of extracellular amyloid-beta(Aβ)plaques(accompanied by increasing intracellular Aβ_(1-42))and higher intracellular neu rofi brilla ry tangles,comprised mostly of hyperphosphorylated tau protein/pTau(Goedert,2015;Hardy,2017).It is evident that the elderly are more predisposed to develop AD,and thus aging is considered to be the primary risk factor for *** extra polation,strategies that delay aging may also slow down(if not stop)AD.

关键词： Alzheimer Aβ tau