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Mbius-invariant curve and surface energies and their applications

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Science China(Information Sciences) 2013年第9期56卷 18-27页

作者： YOSHIZAWA Shin belyaev alexander Image Processing Research Team RIKEN Institute of Sensors Signals & Systems Heriot-Watt University

Curvature-based surface energies are frequently used in mathematics, physics, thin plate and shell engineering, and membrane chemistry and biology studies. Invariance under rotations and shifts makes curvature-based energies very attractive for modeling various phenomena. In computer-aided geometric design, the Willmore surfaces and the so-called minimum variation surfaces (MVS) are widely used for shape modeling purposes. The Willmore surfaces are invariant w.r.t conformal transformations (Mbius or conformal invariance), and studied thoroughly in differential geometry and related disciplines. In contrast, the minimum variation surfaces are not conformal invariant. In this paper, we suggest a simple modification of the minimum variation energy and demonstrate that the resulting modified MVS enjoy Mbius invariance (so we call them conformal-invariant MVS or, shortly, CI-MVS). We also study connections of CI-MVS with the cyclides of Dupin. In addition, we consider several other conformal-invariant curve and surface energies involving curvatures and curvature derivatives. In particular, we show how filtering with a conformal-invariant curve energy can be used for detecting salient subsets of the principal curvature extremum curves used by Hosaka and co-workers for shape quality inspection purposes.

关键词： Willmore energy minimum variation surfaces Dupin’s cyclides Mbius/conformal invariance

IR-transparent MgO-Gd_(2)O_(3) composite ceramics produced by self-propagating high-temperature synthesis and spark plasma sintering

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Journal of Advanced Ceramics 2021年第2期10卷 237-246页

作者： Dmitry A.Permin Maksim S.Boldin alexander V.belyaev Stanislav S.Balabanov Vitaly A.Koshkin Atrem A.Murashov Igor V.Ladenkov Evgeny A.Lantsev Ksenia E.Smetanina Nadia M.Khamaletdinova G.G.Devyatykh institute of chemistry of high-purity substances of the ras nizhny novgorod603137russia Lobachevsky state university of nizhny novgorod nizhny novgorod603950russia “Joint-stock company”research and production enterprise“salut” nizhny novgorod603950russia G.A.Razuvaev institute of organometallic chemistry of the ras nizhny novgorod603137russia

A glycine–nitrate self-propagating high-temperature synthesis(SHS)was developed to produce composite MgO-Gd_(2)O_(3) *** X-ray powder diffraction(XRD)analysis confirmed the SHS-product consists of cubic MgO and Gd_(2)O_(3) phases with nanometer crystallite size and retains this structure after annealing at temperatures up to 1200℃.Near full dense high IR-transparent composite ceramics were fabricated by spark plasma sintering(SPS)at 1140℃and 60 *** in-line transmittance of 1 mm thick MgO-Gd_(2)O_(3) ceramics exceeded 70%in the range of 4–5 mm and reached a maximum of 77%at a wavelength of 5.3 *** measured microhardness HV0.5 of the MgO-Gd2O3 ceramics is 9.5±0.4 GPa,while the fracture toughness(KIC)amounted to 2.0±0.5МPa·m1/*** characteristics demonstrate that obtained composite MgO-Gd_(2)O_(3) ceramic is a promising material for protective infra-red(IR)windows.

关键词： MgO-Gd_(2)O_(3) self-propagating high-temperature synthesis(SHS) spark plasma sintering(SPS) optical properties infra-red(IR)ceramics

Microglia:a promising therapeutic target in spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 454-463页

作者： Xiaowei Zha Guoli Zheng Thomas Skutella Karl Kiening Andreas Unterberg alexander Younsi Department of Neurosurgery Heidelberg University HospitalHeidelbergGermany Department of Neuroanatomy Institute for Anatomy and Cell BiologyHeidelberg UniversityHeidelbergGermany

Microglia are present throughout the central nervous system and are vital in neural repair,nutrition,phagocytosis,immunological regulation,and maintaining neuronal *** a healthy spinal cord,microglia are accountable for immune surveillance,however,when a spinal cord injury occurs,the microenvironment drastically changes,leading to glial scars and failed axonal *** this context,microglia vary their gene and protein expression during activation,and proliferation in reaction to the injury,influencing injury responses both favorably and unfavorably.A dynamic and multifaceted injury response is mediated by microglia,which interact directly with neurons,astrocytes,oligodendrocytes,and neural stem/progenitor *** a clear understanding of their essential nature and origin,the mechanisms of action and new functions of microglia in spinal cord injury require extensive *** review summarizes current studies on microglial genesis,physiological function,and pathological state,highlights their crucial roles in spinal cord injury,and proposes microglia as a therapeutic target.

关键词： astrocytes cytokines functional recovery immune regulation M1/M2 activation macrophages microglia neuroinflammation spinal cord injury therapy

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

NiTi形状记忆合金在恒定应力和温度下保温过程中马氏体相变诱发的可恢复应变

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Transactions of Nonferrous Metals Society of China 2023年第9期33卷 2687-2697页

作者： Sergey belyaev Natalia RESNINA Elena DEMIDOVA Aleksei IVANOV Artur GABRIELYAN alexander SHELYAKOV Vladimir ANDREEV Saint-Petersburg State University 7/9 Universitetskaya nab.Saint-Petersburg 199034Russia National Research Nuclear University MEPhI(Moscow Engineering Physics Institute) 31 Kashirskoe shosseMoscow 115409Russia Baikov Institute of Metallurgy and Materials Science RAS49 Leninskii pr.Moscow 119334Russia

研究NiTi形状记忆合金在应力下等温保温过程中的应变变化。为了研究可恢复应变,对Ni_(51)Ti_(49)和Ti_(40.7)Hf_(9.5)Ni_(44.8)Cu_(5)合金进行3种制度的保温处理,分别是:应力下冷却后在应力下保温(制度1);无应力和载荷下冷却后在应力下... 详细信息

研究NiTi形状记忆合金在应力下等温保温过程中的应变变化。为了研究可恢复应变,对Ni_(51)Ti_(49)和Ti_(40.7)Hf_(9.5)Ni_(44.8)Cu_(5)合金进行3种制度的保温处理,分别是:应力下冷却后在应力下保温(制度1);无应力和载荷下冷却后在应力下保温(制度2);具有双向形状记忆效应的样品在应力下保温(制度3)。结果表明,所有制度中,在应力下保温后样品均会发生应变变化。该应变在后续热处理或卸载后能恢复,因此表明应变变化是由等温马氏体相变引起的。这种等温应变取决于合金的化学成分、等温保温制度、应力和保温温度。Ti_(40.7)Hf_(9.5)Ni_(44.8)Cu_(5)合金(制度1)和Ni_(51)Ti_(49)合金(制度2)的最大等温应变分别为3.4%和6.1%。制度3中的保温伴随着较小的应变(小于0.3%)。讨论储存弹性能对等温马氏体相变的影响,结果表明,当相变伴随着较小的储存弹性能时,等温应变较大。

关键词：等温马氏体相变可恢复应变超弹性应变 NiTi形状记忆合金保温

Computer study of the formation of water-ammonia clusters and their dielectric properties

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Chinese Physics B 2013年第7期22卷 167-172页

作者： alexander Galashev Institute of Industrial Ecology Ural BranchRussian Academy of Sciences

The absorption of one to six ammonia molecules by the （H2O）50 cluster is studied by the molecular dynamics method under near-atmospheric conditions. The capture of NH 3 molecules by a water cluster produces an increase in the integrated intensity of IR absorbance, substantially decreases emission power in the frequency range of 0≤ω≤3500cm-1,and transforms a continuous reflectance spectrum into a banded one. Adsorption of ammonia molecules by water clusters greatly diminishes the number of electrons that are active with respect to electromagnetic radiation. The present results are also compared with the experimental findings wherever available.

关键词： ammonia water cluster infrared absorption spectra molecular dynamics

Chargino Production via Z^0-Boson Decay in a Strong Electromagnetic Field

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Chinese Physics Letters 2016年第3期33卷 17-19页

作者： alexander Kurilin Moscow Technological Institute on leave from Moscow State Open Pedagogical University

In the framework of MSSM the probability of Z0-boson decay to chaxginos in a strong electromagnetic field, Z X＋X-, is analyzed. The method of calculations employs exact solutions of relativistic wave equations for charginos in a crossed electromagnetic field. Analytic expression for the decay width is obtained at an arbitrary value of the parameter which characterizes the external-field strength Fμv and Z%boson momentum qv. The process Z0→ X＋X- is forbidden in a vacuum for the case of relatively heavy charginos： Mx±mz/2. However, in an intense electromagnetic background this reaction could take place in the region of superstrong fields （x〉1）.

关键词： of on is in Chargino Production via Z~0-Boson Decay in a Strong Electromagnetic Field for

Use of GIS technology and cellular automata for modeling multiple socio-economic scenarios of regional spatial development and inter-regional cooperation

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Geo-Spatial Information Science 2023年第1期26卷 71-93页

作者： Igor Musikhin alexander Karpik Department of Photogrammetry and Remote Sensing Siberian State University of Geosystems and TechnologiesNovosibirskRussia Department of Space and Physical Geodesy Siberian State University of Geosystems and TechnologiesNovosibirskRussia

The advancement of effective spatial planning to support sustainable development and interregional cooperation has become an issue of serious concern for regional *** planning research helps to identify economic clusters and analyze their changing spatial patterns,which is important for understanding regional economic space dynamics and poten-tial inter-regional *** support decision-makers in the development of efficient plans of spatial development encompassing the identification of the best-suited territories,a combined Geographic Information System(GIS)based approach to interpret qualitatively expressed multiple socio-economic scenarios in quantitative map-based terms of graded suitability,and a formalized approach to the socio-economic evaluation of the territory is *** on GIS technology coupled with integrated cellular automata decision analysis techniques,the study provides a method that performs socio-economic assessment of the study area according to the generated scenarios of regional spatial and socio-economic *** proposed method is applied to Primorsky and Khabarovsk Krais,located in the Russian Far ***-economic scenarios of spatial development initiated by investors and regional authorities were assessed and *** generated socio-economic scenar-ios illustrate how the unified set of spatial and socio-economic variables can be linked and used to gain insights into inter-regional socio-economic and spatial *** application results demonstrate the advantage of the proposed method in identifying the best-suited unit areas for targeted regional development.

关键词： Geographic Information System(GIS) spatial development socioeconomic scenarios interregional cooperation open source software Cellular Automata(CA)

Volcanic Ash in the Atmosphere and Risks for Civil Aviation:A Study in European Crisis Management

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International Journal of Disaster Risk Science 2013年第1期4卷 9-19页

作者： David alexander Institute for Risk and Disaster Reduction University College London London WC1E 6BT United Kingdom

This paper uses the eruption of the Icelandic volcano Eyjafjallaj?kull in April and May 2010 as a case study of disruption to civil aviation by airborne ash, with emphasis on risk management aspects. Severe curtailment of flights over much of Europe took place during the crisis, which lasted for slightly more than one week. More than 8.5 million passengers were stranded and commerce was profoundly affected. The United Kingdom was one of the worst impacted countries and took the lead in managing the crisis. The paper considers elements of the decision-making process that formed the basis of the UK Government’s emergency response. It examines the relations between science, governance, and economi c imperatives. Physical thresholds guiding decisions to restrict airspace were defined somewhat arbitrarily, which may have increased disruption. A damaging form of risk aversion prevailed at certain points in the crisis. Lack of preexisting procedures and planning meant that the response to dynamically changing meteorological conditions had to be improvised. At the same time, lack of integration between different modes in the European transportation system meant that had the crisis continued any longer there would have been severe problems in moving stranded people and commodities, as well as soaring economic losses. Eruptions similar to or more serious than that of Eyjafjallaj?kull are perfectly possible in Europe in the not-too-distant future.

关键词： Atmosphere aviation meteorological