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Nonabelian Jacobian of smooth projective surfaces-a survey

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Science China Mathematics 2013年第1期56卷 1-42页

作者： REIDER igor Département de Mathématiques l'Université d'Angers2 Boulevard Lavoisier49045 Angers Cedex 01France

The nonabelian Jacobian J(X;L,d) of a smooth projective surface X is inspired by the classical theory of Jacobian of *** is built as a natural scheme interpolating between the Hilbert scheme X [d] of subschemes of length d of X and the stack M X(2,L,d) of torsion free sheaves of rank 2 on X having the determinant OX(L) and the second Chern class(= number) *** relates to such influential ideas as variations of Hodge structures,period maps,nonabelian Hodge theory,Homological mirror symmetry,perverse sheaves,geometric Langlands *** relations manifest themselves by the appearance of the following structures on J(X;L,d):1) a sheaf of reductive Lie algebras;2)(singular) Fano toric varieties whose hyperplane sections are(singular) Calabi-Yau varieties;3) trivalent *** is an expository paper giving an account of most of the main properties of J(X;L,d) uncovered in Reider 2006 and ArXiv:1103.4794v1.

关键词： Jacobian Hilbert scheme vector bundle

Central Asia—A Global Model for the Formation of Epigenetic Deposits in a Platform Sedimentary Cover

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Journal of Earth Science 2022年第2期33卷 278-288页

作者： igor Pechenkin Vladislav Petrov FSBI All-Russian Scientific-Research Institute of Mineral Resources MoscowRussia Institute of Geology of Ore Deposits Petrography Mineralogy and Geochemistry RAS MoscowRussia

Metallogenic specialization of sedimentary cover in Central Asia is determined by its tectonic setting that governs the hydrodynamic regime(exfiltrational or infiltrational)and as a consequence,the hydrogeochemical zonality(type of water and its gaseous and microcomponent composition).Hydrodynamic conditions(distribution of recharge and discharge areas)determine the direction of stratal water flow and location of mineralization resulted from the change in geochemical,thermodynamic,lithological,structural and other *** exfiltrational regime suggests a dependence of the epigenetic mineralization upon the distribution and degree of preservation of hydrocarbon ***,hydrocarbon matter serves as a reducing barrier and ore-concentrating factor during the formation of polymineral concentrations related to stratal oxidation *** supergene epigenetic ore-forming processes are induced by the interaction between the Earth’s sedimentary cover and *** rocks themselves commonly serve as a source of ore *** ore deposition zones on geochemical barriers and ore material source are often located significantly apart from each *** trend of these processes is determined by the position of ore-bearing depressions in large tectonic blocks.

关键词： Central Asia Kyzyl Kum Bukantau ore-forming systems epigenetic ore deposit geology

Numerical simulation of roof cavings in several Kuzbass mines using finite-difference continuum damage mechanics approach

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International Journal of Mining Science and Technology 2020年第2期30卷 157-166页

作者： Mikhail Eremin Gabriel Esterhuizen igor Smolin Institute of Strength Physics and Materials Science Siberian BranchRussian Academy of SciencesTomsk 634055Russian Federation National Institute for Occupational Safety and Health PittsburghPA 15236USA National Research Tomsk State University Tomsk 634050Russian Federation

An essential stage of mine design is an estimation of the steps of the first and periodic roof caving in longwall ***,this is carried out using the field experience and can be much enhanced by numerical *** this work,the finite-difference method was applied coupled with the continuum damage mechanics(CDM)approach to simulate the stress-strain evolution of the rock mass with the underground opening during coal *** steps and stages of roof caving were estimated relying on the numerical simulation data,and they were compared with the field data from several operating mines in the south of the Kuznetsk Basin,*** dependence of the first roof caving step in simulation linearly correlates with field *** results correspond to the actual roofs of longwall panels of the flat-dipping coal seams and the average rate of face advancement is approximately 5 m/day.

关键词： Longwall mining Rock mass Underground openings Roof caving Abutment pressure Numerical simulation

New solutions for old challenges in glaucoma treatment:is taurine an option to consider?

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Neural Regeneration Research 2021年第5期16卷 967-971页

作者： igor Iezhitsa Renu Agarwal School of Medicine International Medical UniversityKuala LumpurMalaysia Volgograd State Medical University Research Centre for Innovative MedicinesVolgogradRussian Federation

Glaucoma is a range of progressive optic neuropathies characterized by progressive retinal ganglion cell loss and visual field *** is recognized as a leading cause of irreversible blindness affecting more than 70 million people ***,reduction of intraocular pressure,a widely recognized risk factor for glaucoma development,is the only pharmacological strategy for slowing down retinal ganglion cell loss and disease ***,retinal ganglion cell death and visual field loss have been observed in normotensive glaucoma,suggesting that the disease process is partially independent of intraocular *** is one of the agents that have attracted attention of researchers *** has been shown to be involved in multiple cellular functions,including a central role as a neurotransmitter,as a trophic factor in the central nervous system development,as an osmolyte,as a neuromodulator,and as a *** also plays a role in the maintenance of the structural integrity of the membranes and in the regulation of calcium transport and *** is known to prevent N-methyl-D-aspartic acid-induced excitotoxic injury to retinal ganglion cells.A recently published study clearly demonstrated that taurine prevents retinal neuronal apoptosis both in vivo and in *** effect of taurine may be attributed to direct inhibition of apoptosis,an activation of brain derived neurotrophic factor-related neuroprotective mechanisms and reduction of retinal oxidative and nitrosative *** studies are needed to fully explore the potential of taurine as a neuroprotective agent,so that it can be applied in clinical practice,particularly for the treatment of *** objective of current review was to summarize recent evidence on neuroprotective properties of taurine in glaucoma.

关键词： apoptosis excitotoxicity glaucoma oxidative and nitrosative stresses retinal neuroprotection taurine

Transport Across Chloroplast Membranes： Optimizing Photosynthesis for Adverse Environmental Conditions

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Molecular Plant 2016年第3期9卷 356-370页

作者： igor Pottosin Sergey Shabala Biomedicat Centre University of Colima Colima Colima 28045 Mexico School of Land and Food University of Tasmania Hobart TAS 7001 Australia

Chloroplasts are central to solar light harvesting and photosynthesis. Optimal chloroplast functioning is vitally dependent on a very intensive traffic of metabolites and ions between the cytosol and stroma, and should be attuned for adverse environmental conditions. This is achieved by an orchestrated regulation of a variety of transport systems located at chloroplast membranes such as porines, solute channels, ion-specific cation and anion channels, and various primary and secondary active transport systems. In this review we describe the molecular nature and functional properties of the inner and outer envelope and thylakoid membrane channels and transporters. We then discuss how their orchestrated regulation affects thylakoid structure, electron transport and excitation energy transfer, proton-motive force partition, ion homeostasis, stromal pH regulation, andvolume regulation. We link the activity of key cation and anion transport systems with stress-specific signaling processes in chloroplasts, and discuss how these signals interact with the signals generated in other organelles to optimize the cell performance, with a special emphasis on Ca^2＋ and reactive oxygen species signaling.

关键词： stroma thylakoid p.m.f. envelope reactive oxygen species programmed cell death

Arteriovenous malformations:the newest Sonic hedgehog game in the postnatal brain

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Neural Regeneration Research 2021年第5期16卷 996-998页

作者： igor Giarretta Roberto Pola Department of Translational Medicine and Surgery Fondazione Policlinico Universitario A.Gemelli IRCCSUniversitàCattolica del Sacro CuoreSchool of MedicineRomeItaly Department of Cardiovascular Sciences Fondazione Policlinico Universitario A.Gemelli IRCCSUniversitàCattolica del Sacro CuoreSchool of MedicineRomeItaly

The morphogen Sonic hedgehog(Shh)is crucial for the embryonic development of the central nervous system,but is also an important player in the postnatal brain,with activities that range from the modulation of self-renewal and specification of neural stem cells to the regulation of neural regeneration after *** Shh signaling occurs also in molecular subclasses of brain tumors,such as medulloblastoma and adult glioma.

关键词： Shh neural venous

A phase-space formulation and Gaussian approximation of the filtering equations for nonlinear quantum stochastic systems

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Control Theory and Technology 2017年第3期15卷 177-192页

作者： igor G. VLADIMIROV College of Engineering and Computer Science Australian National University Canberra ACT 2601 Australia

This paper is concerned with a filtering problem for a class of nonlinear quantum stochastic systems with multichannel nondemolition measurements. The system-observation dynamics are governed by a Markovian Hudson-Parthasarathy quantum stochastic differential equation driven by quantum Wiener processes of bosonic fields in vacuum state. The Hamiltonian and system-field coupling operators, as functions of the system variables, are assumed to be represented in a Weyl quantization form. Using the Wigner-Moyal phase-space framework, we obtain a stochastic integro-differential equation for the posterior quasi-characteristic function （QCF） of the system conditioned on the measurements. This equation is a spatial Fourier domain representation of the Belavkin-Kushner-Stratonovich stochastic master equation driven by the innovation process associated with the measurements. We discuss a specific form of the posterior QCF dynamics in the case of linear system-field coupling and outline a Gaussian approximation of the posterior quantum state.

关键词： Quantum stochastic system quantum filtering equation Gaussian approximation

MAC Models in Thermoelasticity

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Transactions of Nanjing University of Aeronautics and Astronautics 2014年第2期31卷 127-131页

作者： igor Neygebauer College of Natural Sciences and Mathematics University of Dodoma

There are two types of singularities in the linear *** first one arises in the field of stresses if a force is applied to one point of the *** singularity is physical and should be *** second type of singularities is nonphysical and they arise in the fields of displacements and *** exist the nonlocal theories and gradient theories which have the goal to introduce the finite stresses instead of the infinite *** MAC model of the thermoelasticity is created to avoid the nonphysical singularities and it accepts the infinite *** is the method of additional conditions,which allows introducing the new model to use the classical model,plus additional condition of the physical nonsingularity and/or condition of the good behavior of the solutions at *** MAC Green′s functions for the heat conduction and for the elasticity could be introduced using the differential MAC *** infinite and finite bodies are *** principle of superposition is applied to obtain the integral equations to solve the boundary value *** strength criteria based on finite stresses could be changed in this model because the infinite stresses are *** strength criteria based on deformations are *** of MAC models is given.

关键词： MAC model constitutive equations thermoelasticity

Model-based interpretation of bottomhole pressure records during matrix treatments in layered formations

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Petroleum Science 2024年第5期21卷 3587-3611页

作者： igor Reznikov Dmitry Abdrazakov Dimitry Chuprakov Schlumberger Moscow Research Leningradskoe shossebldg.16Acorp.3Moscow125171Russian Federation Novosibirsk Technology Center 1/10 Zelenaya Gorka strNovosibirsk630060Russian Federation

During injection treatments, bottomhole pressure measurements may significantly mismatch modeling results. We devise a computationally effective technique for interpretation of fluid injection in a wellbore interval with multiple geological layers based on the bottomhole pressure measurements. The permeability, porosity and compressibility in each layer are initially setup, while the skin factor and partitioning of injected fluids among the zones during the injection are found as a solution of the problem. The problem takes into account Darcy flow and chemical interactions between the injected acids, diverter fluids and reservoir rock typical in modern matrix acidizing treatments. Using the synchronously recorded injection rate and bottomhole pressure, we evaluate skin factor changes in each layer and actual fluid placement into the reservoir during different pumping jobs: matrix acidizing, water control, sand control, scale squeezes and water flooding. The model is validated by comparison with a simulator used in industry. It gives opportunity to estimate efficiency of a matrix treatment job, role of every injection stage, and control fluid delivery to each layer in real time. The presented interpretation technique significantly improves accuracy of matrix treatments analysis by coupling the hydrodynamic model with records of pressure and injection rate during the treatment.

关键词： Matrix treatment Inverse problem Forward problem Skin factor Interpretation