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Myelin histology:a key tool in nervous system research

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Neural Regeneration Research 2024年第2期19卷 277-281页

作者： Óscar Darío García-García víctor Carriel Jesús Chato-Astrain Department of Histology Tissue Engineering GroupUniversity of Granada&Instituto de Investigación Biosanitaria ibs.GRANADAGranadaSpain

The myelin sheath is a lipoprotein-rich,multilayered structure capable of increasing conduction velocity in central and peripheral myelinated nerve *** to the complex structure and composition of myelin,various histological techniques have been developed over the centuries to evaluate myelin under normal,pathological or experimental ***,methods to assess myelin integrity or content are key tools in both clinical diagnosis and neuroscience *** this review,we provide an updated summary of the composition and structure of the myelin sheath and discuss some histological procedures,from tissue fixation and processing techniques to the most used and practical myelin histological staining *** the lipoprotein nature of myelin,the main features and technical details of the different available methods that can be used to evaluate the lipid or protein components of myelin are described,as well as the precise ultrastructural techniques.

关键词： fluorescence microscopy histology light microscopy lipid histochemistry metallographic techniques myelin histochemistry myelin immunohistochemistry myelin structure&composition myelin ultrastructural evaluation tissue fixation&processing

SANC Monte Carlo programs for small-angle Bhabha scattering

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Chinese Physics C 2024年第4期48卷 14-19页

作者： A.B.Arbuzov S.G.Bondarenko I.R.Boyko L.v.Kalinovskaya A.A.Kampf R.R.Sadykov v.L.Yermolchyk Bogoliubov Laboratory of Theoretical Physics JINRDubna141980 Russia Dzhelepov Laboratory of Nuclear Problems JINRDubna141980 Russia Dubna State University Dubna141982 Russia

Luminosity monitoring at e^(+)e^(−)colliders was investigated using SANC Monte Carlo event generator ReneSANCe and integrator MCSANC for simulation of Bhabha scattering at low *** are presented for center-of-mass energies of the Z boson resonance and at 240 Gev for the conditions of typical luminosity *** is shown that bremsstrahlung events with extremely low electron scattering angles are relevant to match the precision tags of future electron-positron colliders.

关键词： luminosity Bhabha scattering QeD Monte Carlo simulation

Pulsed THz radiation under ultrafast optical discharge of vacuum photodiode

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Frontiers of Optoelectronics 2024年第2期 100-113页

作者： Aleksandr A.Ushakov Kseniia A.Mamaeva Leonid v.Seleznev Georgy e.Rizaev vladimir Bukin Timophey v.Dolmatov Pavel A.Chizhov vladimir Bagdasarov Sergey v.Garnov Prokhorov General Physics Institute of the Russian Academy of Sciences Physical Institute Russian Academy of Sciences Moscow Institute of Physics and Technology Russian Institute for Scientific and Technical Information

In this paper, we first present an experimental demonstration of terahertz radiation pulse generation with energy up to 5 pJ under the electron emission during ultrafast optical discharge of a vacuum photodiode. We use a femtosecond optical excitation of metallic copper photocathode for the generation of ultrashort electron bunch and up to 45 kv/cm external electric field for the photo-emitted electron acceleration. Measurements of terahertz pulses energy as a function of emitted charge density, incidence angle of optical radiation and applied electric field have been provided. Spectral and polarization characteristics of generated terahertz pulses have also been studied. The proposed semi-analytical model and simulations in COMSOL Multiphysics prove the experimental data and allow for the optimization of experimental conditions aimed at flexible control of radiation parameters.

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Older Adult Compendium of Physical Activities:energy costs of human activities in adults aged 60 and older

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Journal of Sport and Health Science 2024年第1期13卷 13-17,F0003页

作者： erik A.Willis Stephen D.Herrmann Mary Hastert Chelsea L.Kracht Tiago v.Barreira John M.Schuna Jr. Zhenghua Cai Minghui Quan Scott A.Conger Wendy J.Brown Barbara e.Ainsworth Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA Kansas Center for Metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Clinical Science Division Pennington Biomedical Research CenterBaton RougeLA 70808USA exercise Science Department Syracuse UniversitySyracuseNY 13244USA School of exercise&Sport Science Oregon State UniversityCorvallisOR 97331USA School of exercise and Health Shanghai University of SportShanghai 200438China Department of Kinesiology Boise State UniversityBoiseID 83725USA School of Human Movement and Nutrition Sciences The University of QueenslandSt.LuciaQLD 4072Australia Faculty of Health Sciences and Medicine Bond UniversityGold CoastQLD 4229Australia College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MeT)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,embase,SPORTDiscus(eBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older *** values were computed as the oxygen cost(vO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(MeT_(60+))to account for the lower resting metabolic rate in older ***:We identified 68 articles and extracted energy expenditure data on 427 *** these,we derived 99 unique Specific Activity codes with corresponding MeT_(60+)values for older *** developed a website to present the OA Compendium MeT_(60+)values:https://***:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older *** is an accessible resource that will allow researchers,educators,and practitioners to find MeT_(60+)values for older adults for use in PA research and practice.

关键词： energy expenditure exercise MeT Older adults

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什么样的火山会“发火”

当代学生 2024年第1期 26-28页

作者： e.v 不详

地处北大西洋和北冰洋交汇处的冰岛,本就是一个地质活动频繁的国家,前不久更是曾进入了全国紧急状态,不少城镇的居民举家搬家,去往了更为安全的地方。究竞怎样的火山容易爆发?冰岛会不会成为下一个庞贝古城?只有了解火山的“脾气”,我... 详细信息

地处北大西洋和北冰洋交汇处的冰岛,本就是一个地质活动频繁的国家,前不久更是曾进入了全国紧急状态,不少城镇的居民举家搬家,去往了更为安全的地方。究竞怎样的火山容易爆发?冰岛会不会成为下一个庞贝古城?只有了解火山的“脾气”,我们才能知道它什么时候会“发火”。

关键词：庞贝古城北冰洋紧急状态北大西洋冰岛火山发火

Interaction of photons with silver and indium nuclei at energies up to 20 Mev

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Chinese Physics C 2024年第2期48卷 135-140页

作者： J.H.Khushvaktov M.A.Demichev D.L.Demin S.A.evseev M.I.Gostkin v.v.Kobets F.A.Rasu-lova S.v.Rozov e.T.Ruziev A.A.Solnyshkin T.N.Tran e.A.Yakushev B.S.Yuldashev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan(INP ASRU) TashkentUzbekistan Institute of Physics of the vietnam Academy of Science and Technology(IP vAST) HanoiVietnam

The yields of photonuclear reactions in the 107Ag,113In,and 115In nuclei were *** Carlo simulations were performed using the Geant4 code,and the results were compared with the experimental *** isomeric ratios of the yields in the reactions 107Ag(γ,n)106m,gAg and 113In(γ,m)112m,gIn were determined,and the cross sections for the reactions 107Ag(γ,n)106gAg and 107Ag(γ,2n)105Ag at an energy of 20 Mev were calculated based on the experimental data.

关键词： 107Ag(γ,n)10mgAg and I13In(γ,n)12m-2In reactions cross section yield isomeric ratio simula-tion Geant4 TALYS

Neurogenic potential of NG2 in neurotrauma:a systematic review

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Neural Regeneration Research 2024年第12期19卷 2673-2683页

作者： Yuri R.Rigo Radharani Benvenutti Luis v.Portela Nathan R.Strogulski Departamento de Bioquímica Instituto de Ciências Básicas da SaúdeUniversidade Federal do Rio Grande do Sul(UFRGS)Porto AlegreBrazil School of Pharmacy and Biomolecular Sciences RCSI University of Medicine and Health SciencesDublinIreland School of Biochemistry and Immunology Trinity Biomedical Sciences InstituteTrinity College DublinUniversity of DublinDublinIreland

Regenerative approaches towards neuronal loss following traumatic brain or spinal cord injury have long been considered a dogma in neuroscience and remain a cutting-edge area of *** is reflected in a large disparity between the number of studies investigating primary and secondary injury as therapeutic to rgets in spinal co rd and traumatic brain *** advances in biotechnology may have the potential to reshape the current state-of-the-art and bring focus to primary injury neurotrauma *** studies using neural-glial factor/antigen 2(NG2)cells indicate that they may differentiate into neurons even in the developed *** these cells show great potential to play a regenerative role,studies have been conducted to test various manipulations in neurotrauma models aimed at eliciting a neurogenic response from *** the present study,we systematically reviewed the experimental protocols and findings described in the scientific literature,which were peer-reviewed original research articles(1)describing preclinical experimental studies,(2)investigating NG2 cells,(3)associated with neurogenesis and neurotrauma,and(4)in vitro and/or in vivo,available in PubMed/MeDLINe,Web of Science or SCOPUS,from 1998 to ***,we have reviewed a total of 1504 papers,and summarized findings that ultimately suggest that NG2 cells possess an inducible neurogenic potential in animal models and in *** also discriminate findings of NG2 neurogenesis promoted by different pharmacological and genetic approaches over functional and biochemical outcomes of traumatic brain injury and spinal co rd injury models,and provide mounting evidence for the potential benefits of manipulated NG2 cell ex vivo transplantation in primary injury *** findings indicate the feasibility of NG2 cell neurogenesis strategies and add new players in the development of therapeutic alternatives for neurotrauma.

关键词： neural-glial antigen 2 neural-glial factor 2 neuron differentiation NG2 cell regeneration spinal cord injury(SCI) traumatic brain injury(TBI)

A stability evaluation method for deep-seated toppling in the upper Lancang river,Southwestern China

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Journal of Rock Mechanics and Geotechnical engineering 2024年第7期16卷 2388-2410页

作者： Yibing Ning Huiming Tang Jianbing Peng Yanjun Shen John v.Smith Bocheng Zhang College of Geological engineering and Geomatics Chang’an UniversityXi’an710054China Academy of Yellow River Sciences of Shaanxi Province Chang’an UniversityXi’an710054China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan430074China School of engineering RMIT UniversityMelbourne3001Australia

Deep-seated toppling in the upper reaches of the Lancang River,southwest China involves deformations exceeding 100 m in *** slope deformation is initiated by river downcutting and evolves distinctive characteristics with a depth of river *** this study,we propose a system for evaluating the stability of deep-seated toppled slopes in different evolutionary *** system contains identification criteria for each evolutionary stage and provides the corresponding stability evaluation *** on the mechanical and kinematic analysis of slope blocks,the specific stage of slope movement can be identified in the field through outcrop mapping,in situ tests,surface displacement monitoring,and adit and borehole *** stability evaluation methods are established based on the limiting equilibrium theory and the strain compatibility between the undisturbed zone and the toppled ***,several sample slopes in different evolution stages have been investigated to verify the applicability and accuracy of the proposed stability evaluation *** results indicate that intense tectonic activity and rapid river incision lead to a maximum principal stress ratio exceeding 10 near the slope surface,thus triggering widespread toppling deformations along the river *** considering the losses of joint cohesion during the further rotation process,the safety factor of the slope drops by 7%e28%.The self-stabilization of toppling deformation can be recognized by the layer symmetry configuration after the free rotation of the deflected *** toppled rock blocks mainly suffer sliding failures beyond the layer symmetry *** factor of safety of the K73 rockslide decreased from 1.17 to 0.87 by considering the development of the potential sliding surface and the toesaturated zone.

关键词： Stability evaluation Deep-seated toppling evolutionary process Reservoir impoundment Rock slope

BaTiO_(3)solid solutions co-doped with Gd^(3+)and eu^(3+):Synthesis,structural evolution and dielectric properties

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Journal of Rare earths 2024年第10期42卷 1920-1926页

作者： R.Martínez-López M.Pérez-Labra J.A.Romero-Serrano F.R.Barrientos-Hernández M.Reyes-Pérez M.I.valenzuela-Carrillo G.Urbano-Reyes v.e.Reyes-Cruz G.I.Dávila-Pulido Academic Area of earth Sciences and Materials Autonomous University of Hidalgo StateRoad Pachuca-Tulancingo Km 4.5 Mineral de La Reforma.Hidalgo42184Mexico Metallurgy and Materials Department ESIQIE-IPNUPALMZacatencoCiudad de Mexico07738Mexico Autonomous University of Coahuila Boulevard Adolfo López Mateos S/nNueva RositaCoahuila26800Mexico

In this paper,the synthesis,structural evolution,and dielectric properties of BaTiO_(3)solid solutions codoped with rare earth elements(Gd^(3+)and eu^(3+))prepared using the solid-state reaction method are *** pure precursor powders of BaCl_3,TiO_(2),Gd_(2)O_(3),and eu_(2)O_(3)were mixed in stoichiometric proportions,ground in an agate mortar before being uniaxially pressed at 250 MPa and sintered at 1300℃in air atmosphere for 6 h to obtain Ba_(1-3x)Gd_(2x)Ti_(1-3x)eu_(4x)O_(3)(x=0,0.0015,0.01 and0.1).X-ray diffraction(XRD)and Rietveld's refinement results reveal the crystal phase ferroelectric tetragonal BaTiO_(3)for the samples with x=0,0.0015 and 0.01,as well as a consistent increment in the lattice parameters caused by the *** solubility limit of Gd^(3+)and eu^(3+)in the BaTiO_(3)structure is reached for the sample with x>0.01,and the orthorhombic eu_2TiO_(5)and monoclinic BaTi_(2)O_(5)secondary phases were *** Raman results show the characteristic peaks of ferroelectric tetragonal BaTiO_(3)around 716 cm^(-1)(LO of A1 symmetry),515 cm^(-1)(TO of A1 symmetry),and 305 cm^(-1)(B1).The maximum relative permittivity measured at 1 kHz was recorded to be 6151.8 for the sample with x=0.0015,and a decrease in the Curie temperature to 105℃with respect to the undoped sample was *** punctual microanalysis for the samples with x=0.0015,0.01,and 0.1 reveals grains composed of Ba,Ti,O,Gd,and eu homogeneously distributed in the BaTiO_(3)*** Ba/Ti ratios for samples with x=0.0015,0.01 and 0.1 are 2.86,2.91,and 0.68,respectively,indicating substitution at the Ti site for samples with x=0.0015 and 0.01 and a substitution at the Ba site for the sample with x=0.1.

关键词： BaTiO_(3) Doping Gadolinium europium Synthesis Rare earths