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Transactions of Tianjin University 2024年第6期30卷 508-517页

作者： Maria Timofeeva Dmitry s.Dmitriev Danil D.Maltsev Artem A.Lobinsky Valentina V.Ivashchenko svyatoslav A.Povarov Daria V.Dogadina alexander s.timin Valentin A.Milichko Vadim I.Popkov sergei A.shipilovskikh ITMO University St.PetersburgRussia 191002 Ioff e Institute St.PetersburgRussia 194021 Peter the Great st.Petersburg Polytechnic University St.PetersburgRussia 195251 Institut Jean Lamour Universit´E de Lorraine54000 NancyFrance

Porous metal–organic frameworks(MOFs) have been recently discovered to be efficient catalysts for energy applications and green technologies. Here, we report on a scalable catalytic platform using Cu–based MOFs for electrocatalytic alkaline hydrogen evolution reaction. First, the solvothermal synthesis of Cu–BTC MOFs(BTC = 1,3,5–benzenetricarboxylate) at 85 ℃ and a 1:60 ligand–to–solvent ratio allowed for minimizing the chemical consumption. second, the obtained platform demonstrated enhanced electrochemical performance compared with commercially available Cu–based MOFs, with a potential of –230 versus –232 eV, logarithm of the current density of –3.6 versus –4.2 cm2, and electrochemical surface area of 75 versus 25 cm2per cm2of geometric area, respectively. Morphological and Raman analyses also revealed that the high concentration of defects in the obtained submicron Cu–BTC MOFs can contribute to their improved catalytic performance. Thus, our findings pave the way to the low–cost synthesis of energy–efficient MOF–based catalysts for hydrogen production.

关键词： Electrocatalysis Metal-organic frameworks Hydrogen evolution reaction Copper-based solvothermal synthesis

Revisiting cerebral endothelial cells in Alzheimer’s disease

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Neural Regeneration Research 2025年第10期20卷 2911-2912页

作者： Amira s.Hanafy Department of Neurosurgery University Hospital BonnBonnGermany

Alzheimer’s disease(AD)is the most common neurodegenerative disorder characterized by slow and progressive decline of cognitive and memory *** only approximately 5%of the cases,AD is familial,as often predisposed by genetic mutations(Hoogmartens et al.,2021),while sporadic AD accounts for approximately 95%of the *** amyloid cascade hypothesis is one of the fundamental hypotheses put out to explain AD pathogenesis as dysregulated homeostasis of amyloid-β(Aβ)peptides that leads to the accumulation of Aβplaques in the parenchyma,an anatomical hallmark of AD.

关键词： Alzheimer Aβ cerebral

Treating amyotrophic lateral sclerosis with allogeneic schwann cell-derived exosomal vesicles: a case report

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Neural Regeneration Research 2025年第4期20卷 1207-1216页

作者： Pascal J.Goldschmidt-Clermont Aisha Khan George Jimsheleishvili Patricia Graham Adriana Brooks Risset silvera alexander J.P.Goldschmidt Damien D.Pearse W.Dalton Dietrich Allan D.Levi James D.Guest Miller school of Medicine University of MiamiMiamiFLUSA stem Cell Institute Miller School of MedicineUniversity of MiamiMiamiFLUSA The Miami Project to Cure Paralysis Miller School of MedicineUniversity of MiamiMiamiFLUSA Alzady International LLC MiamiFLUSA Neurological surgery Miller School of MedicineUniversity of MiamiMiamiFLUSA

schwann cells are essential for the maintenance and function of motor neurons,axonal networks,and the neuromuscular *** amyotrophic lateral sclerosis,where motor neuron function is progressively lost,schwann cell function may also be ***,important signaling and potential trophic activities of schwann cell-derived exosomal vesicles have been *** case report describes the treatment of a patient with advanced amyotrophic lateral sclerosis using serial intravenous infusions of allogeneic schwann cell-derived exosomal vesicles,marking,to our knowledge,the first instance of such *** 81-year-old male patient presented with a 1.5-year history of rapidly progressive amyotrophic lateral *** initial diagnosis,the patient underwent a combination of generic riluzole,sodium phenylbutyrate for the treatment of amyotrophic lateral sclerosis,and *** patient volunteered to participate in an FDA-approved single-patient expanded access treatment and received weekly intravenous infusions of allogeneic schwann cell-derived exosomal vesicles to potentially restore impaired schwann cell and motor neuron *** confirmed that cultured schwann cells obtained from the amyotrophic lateral sclerosis patient via sural nerve biopsy appeared impaired(senescent)and that exposure of the patient’s schwann cells to allogeneic schwann cell-derived exosomal vesicles,cultured expanded from a cadaver donor improved their growth capacity in *** a period of observation lasting 10 weeks,during which amyotrophic lateral sclerosis Functional Rating scale-Revised and pulmonary function were regularly monitored,the patient received weekly consecutive infusions of 1.54×1012(×2),and then consecutive infusions of 7.5×1012(×6)allogeneic schwann cell-derived exosomal vesicles diluted in 40 mL of Dulbecco’s phosphate-buffered *** of the infusions were associated with adverse events such as infusion reactions(allergic or otherwise)or

关键词： allogeneic amyotrophic lateral sclerosis exosomes infusion neuromuscular junction schwann cell

sIMPLE COMPUTING OF THE CUsTOMER LIFETIME VALUE:A FIXED LOCAL-OPTIMAL POLICY APPROACH

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Journal of systems science and systems Engineering 2014年第4期23卷 439-459页

作者： Julio B.Clempner alexander s.Poznyak Center for Economics Management and Social Research Department of Control Automatics Center for Research and Advanced studies

In this paper,we present a new method for finding a fixed local-optimal policy for computing the customer lifetime *** method is developed for a class of ergodic controllable finite Markov *** propose an approach based on a non-converging state-value function that fluctuates（increases and decreases） between states of the dynamic *** prove that it is possible to represent that function in a recursive format using a one-step-ahead fixed-optimal ***,we provide an analytical formula for the numerical realization of the fixed local-optimal *** also present a second approach based on linear programming,to solve the same problem,that implement the c-variable method for making the problem computationally *** the end,we show that these two approaches are related：after a finite number of iterations our proposed approach converges to same result as the linear programming *** also present a non-traditional approach for ergodicity *** validity of the proposed methods is successfully demonstrated theoretically and,by simulated credit-card marketing experiments computing the customer lifetime value for both an optimization and a game theory approach.

关键词： Customer lifetime value optimization optimal policy method linear programming ergodic controllable Markov chains asynchronous games

A simple semiempirical model for the static polarizability of electronically excited atoms and molecules

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Chinese Physics B 2023年第4期32卷 290-301页

作者： alexander s sharipov Alexey V Pelevkin Boris I Loukhovitski Central Institute of Aviation Motors Aviamotornaya 2Moscow 111116Russia

We present a semiempirical analytical model for the static polarizability of electronically excited atoms and molecules,which requires very few readily accessible input data,including the ground-state polarizability,elemental composition,ionization potential,and spin multiplicities of excited and ground *** very simple model formulated in a semiclassical framework is based on a number of observed trends in polarizability of electronically excited *** adjust the model,both accurate theoretical predictions and reliable measurements previously reported elsewhere for a broad range of multielectron species in the gas phase are *** some representative compounds of general concern that have not yet attracted sufficient research interest,the results of our multireference second-order perturbation theory calculations are additionally *** show that the model we developed has reasonable(given the considerable uncertainties in the reference data)accuracy in predicting the static polarizability of electronically excited species of arbitrary size and excitation *** findings can be useful for many applications,where there is a need for inexpensive and quick assessments of the static gas-phase polarizability of excited electronic states,in particular,when building the complex nonequilibrium kinetic models to describe the observed optical refractivity(dielectric permittivity)of nonthermal reacting gas flows.

关键词： polarizability electronic excitation semiempirical model quantum chemistry

A simple semiempirical model for the static polarizability of ions

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Chinese Physics B 2023年第8期32卷 32-45页

作者： alexander s sharipov Boris I Loukhovitski Central Institute of Aviation Motors Aviamotornaya 2Moscow 111116Russia

A concise analytical model for the static dipole polarizability of ionized atoms and molecules is created for the first *** input,it requires,alongside the polarizability of neutral counterpart of a given ion,only the charge and elemental *** physically motivated semiempirical model is based on a number of established regularities in polarizability of charged monatomic and polyatomic *** order to adjust it,the results of quantum chemistry calculations and gas-phase measurements available for a broad range of ionized multielectron species are *** counteract the appreciable bias in the literature data toward polarizability of monoatomic ions,for some molecular ions of general concern the results of the authors'own density functional theory calculations are additionally invoked.A total of 541 data points are used to optimize the *** is demonstrated that the model we suggested has reasonable(given the substantial uncertainties of the reference data)accuracy in predicting the static isotropic polarizability of arbitrarily charged ions of any size and atomic *** resulting polarizability estimates are found to achieve a coefficient of determination of 0.93 for the assembled data *** created analytic tool is universally applicable and might be advantageous for some applications where there is an urgent need for rapid low-cost evaluation of the static gas-phase polarizability of ionized atoms and *** is especially relevant to constructing the complex models of nonequilibrium chemical kinetics aimed at precisely describing the observable refractive index(dielectric permittivity)of plasma *** data sets that support the findings of this study are openly available in science Data Bank at https://***/10.57760/sciencedb.07526.

关键词： polarizability ions semiempirical model quantum chemistry

Interatomic Interaction Models for Magnetic Materials:Recent Advances

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Chinese Physics Letters 2024年第6期41卷 54-66页

作者： Tatiana s.Kostiuchenko alexander V.shapeev Ivan s.Novikov Emanuel Institute of Biochemical Physics RAs 4 Kosygin StreetMoscow119334Russian Federation Independent investigator

Atomistic modeling is a widely employed theoretical method of computational materials *** has found particular utility in the study of magnetic ***,magnetic empirical interatomic potentials or spinpolarized density functional theory(DFT)served as the primary models for describing interatomic interactions in atomistic simulations of magnetic ***,in recent years,a new class of interatomic potentials known as magnetic machine-learning interatomic potentials(magnetic MLIPs)has *** MLIPs combine the computational efficiency,in terms of CPU time,of empirical potentials with the accuracy of DFT *** this review,our focus lies on providing a comprehensive summary of the interatomic interaction models developed specifically for investigating magnetic *** also delve into the various problem classes to which these models can be ***,we offer insights into the future prospects of interatomic interaction model development for the exploration of magnetic materials.

关键词： materials interaction empirical

Finding symmetry Groups of some Quadratic Programming Problems

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Numerical Mathematics(Theory,Methods and Applications) 2023年第2期16卷 370-392页

作者： Anton V.Eremeev alexander s.Yurkov sobolev Institute of Mathematics sB RAs Omsk DepartmentOmskRussia Omsk scientific Center sB RAs(Institute of Radiophysics and Physical Electronics) OmskRussia

solution and analysis of mathematical programming problems may be simplified when these problems are symmetric under appropriate linear *** particular,a knowledge of the symmetries may help decrease the problem dimension,reduce the size of the search space by means of linear *** the previous studies of symmetries in the mathematical programming usually dealt with permutations of coordinates of the solutions space,the present paper considers a larger group of invertible linear *** study a special case of the quadratic programming problem,where the objective function and constraints are given by quadratic *** formulate conditions,which allow us to transform the original problem to a new system of coordinates,such that the symmetries may be sought only among orthogonal *** particular,these conditions are satisfied if the sum of all matrices of quadratic forms,involved in the constraints,is a positive definite *** describe the structure and some useful properties of the group of symmetries of the *** that,the methods of detection of such symmetries are outlined for different special cases as well as for the general case.

关键词： Non-convex programming orthogonal transformation symmetry group Lie group

A spotlight on snow leopard conservation in China

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Integrative Zoology 2016年第4期11卷 308-321页

作者： Justine s alexander Chengcheng ZHANG Kun sHI Philip RIORDAN The Wildlife Institute School of Nature ConservationBeijing Forestry UniversityBeijingChina Department of Zoology University of OxfordOxfordUK Wildlife Without Borders UK Tubney HouseOxfordshireUK

China holds the greatest proportion of the snow leopard’s(Panthera uncia)global range and is central to their *** country is also undergoing unprecedented economic growth,which increases both the threats to the snow leopard and the opportunities for its *** this paper we aim to review published literature(from 1950 to 2014)in English and Mandarin on snow leopard ecology and conservation in China in order to identify thematic and geographic research gaps and propose research *** first retrieved all published items that considered snow leopards in China(n=106).We extracted from these papers 274 reports of snow leopard presence in *** then reviewed a subset of papers(n=33)of this literature,which specifically focused on snow leopard ecology and conservation within *** introduced a thematic framework that allows a structured and comprehensive assessment of *** framework recognizes 4 critical and interrelated topics underpinning snow leopard ecology and conservation:habitat(distribution and protected area coverage);prey(distribution and abundance,predator-prey relationships);human interactions(hunting and trade,livestock interactions and conflicts);and the underlying policy *** gains in knowledge as well as research gaps and priorities are discussed with reference to our *** modest quantity and limited scope of published research on the snow leopard in China calls for a continued and intensified effort to inform and support national conservation policies.

关键词： China conservation Panthera uncia research prioritization

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Gushing metal chain

Frontiers of Mechanical Engineering 2016年第1期11卷 95-100页

作者： alexander BELYAEV alexander sUKHANOV alexander TsVETKOV Institute of Applied Mathematics and Mechanics Saint-Petersburg Polytechnic University St. Petersburg 195251 Russia

This article addresses the problem in which a chain falls from a glass from some height. This phenomenon demonstrates a paradoxical rise of the chain over the glass. To explain this effect, an initial hypothesis and an appropriate theory are proposed for calculating the steady fall parameters of the chain. For this purpose, the modified Cayley ＇s problem of falling chain given its rise due to the centrifugal force of upward inertia is solved. Results show that the lift caused by an increase in linear density at the part of chain where it is being bent （the upper part） is due to the convergence of the chain balls to one another. The experiments confirm the obtained estimates of the lifting chain.

关键词： chain fountain Meshchersky equation,Cayley's problem