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Charged Gravastar in a Dark Energy Universe

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Journal of Modern Physics 2013年第6期4卷 869-878页

作者： C.F.C.Brandt r.chan M.F.A.da Silva P.rocha Departamento de Fisica Teorica Instituto de FisicaUniversidade do Estado do Rio de JaneiroRua Sao Francisco Xavier 524MaracanaRio de Janeiro-RJBrasil Coordenacao de Astronomia e Astrofisica Observatorio NacionalRua General Jose Cristino77Sao CristovaoRio de JaneiroRJBrazil IST-Instituto Superior de Tecnologia de Paracambi FAETECRua Sebastiao de Lacerda s/nBairro da FabricaParacambiRJBrazil

Here we constructed a charged gravastar model formed by an interior de Sitter spacetime, a charged dynamical infinitely thin shell with an equation of state and an exterior de Sitter-reissner-Nordstrom spacetime. We find that the presence of the charge is crucial to the stability of these structures. It can as much favor the stability of a bounded excursion gravastar, and still converting it in a stable gravastar, as make disappear a stable gravastar, depending on the range of the charge considered. There is also formation of black holes and, above certain values, the presence of the charge allows the formation of naked singularity. This is an important example in which a naked singularity emerges as a consequence of unstabilities of a gravastar model, which reinforces that gravastar is not an alternative model to black hole.

关键词： Gravastar Charge De Sitter-reissner-Nordstrom Spacetime Black Hole Naked Singularity Dark Energy

Uncoupling Oligodendrocyte Differentiation and Myelination: Dynamic Neuronal Signaling Not required

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Uncoupling Oligodendrocyte Differentiation and Myelination: ...

中国神经科学学会第十二届全国学术会议

作者： Sonia r.Mayoral Ainhoa Etxeberria Chin J.Shin Chew S.Yian Jonah r.chan Department of Neurology University of California School of Chemical and Biomedical Engineering Lee Kong Chian School of Medicine Nanyang Technological University

Myelination in the CNS is thought to occur via two distinct, but coupled processes. First, highly proliferative and migratory oligodendrocyte precursor cells（OPCs） differentiate into mature oligodendrocytes（OLs）. Second, OL processes concentrically wrap around selected axons forming myelin. These processes occur in a spatially and temporally stereotyped manner throughout development, which implies that environmental cues are at play in the regulation of OL differentiation and myelination. It is thought that dynamic neuronal signaling involving transcriptional control and neuronal activity plays a major role in regulating these processes, but it is unclear whether this is the case in the early development of white matter tracts, such as the optic nerve, where there is synchronous and robust differentiation and myelination within a short timeframe. By eliminating dynamic neuronal signaling in the optic nerve our findings indicate that（1） OL differentiation and myelination are indeed coupled processes where myelination will occur upon differentiation if provided with a permissive substrate, and（2） dynamic neuronal signaling is not required for the majority of OL differentiation during early white matter development. We propose a model in which OL differentiation is largely regulated by extrinsic, non-neuronal factors during development, but myelination is sensitive to the biophysical properties of axonal diameter.

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石墨/环氧航天器设备的设计、分析和试验

国外导弹与航天运载器 1990年第12期 66-73页

作者： J.Hamilton r.chan 李德清

在1988—1989年度开展了一系列复合材料工程项目的(包括设计、分析、制造和试验)研制工作。本文扼要地介绍用于生产重量轻、成本低、零件数量最少的石墨/环氧航天器设备的方法,这种方法采用了同步工程技术,即使用计算机综合工程和制造技... 详细信息

在1988—1989年度开展了一系列复合材料工程项目的(包括设计、分析、制造和试验)研制工作。本文扼要地介绍用于生产重量轻、成本低、零件数量最少的石墨/环氧航天器设备的方法,这种方法采用了同步工程技术,即使用计算机综合工程和制造技术(CIEM)。在证明了提高刚度,尺寸稳定性和降低成本的同时,较之铝合金结构,估计节省重量达20％。制造、分析和设计的密切配合生产出厂內运输损失最少的设备并促进了生产性对话。设计小组设计的结构满足了任务的要求并协调了系统的综合性.利用三维计算机图形扩充设计和制造技术(CADAM)的网格设计方法保证了几何形状的完整性并为分析、制造和试验提供了一种工程通用的数据库。分析人员利用有限元模型和闭式方法为最佳强度/刚度比规定了层压制品技术条件并大大地降低了所推导出的几何形状的结构危险。包括刚度、强度、动载和热冲击试验在内的全部结构试验项目证明设计准则是满意的。

关键词：航天器设备石墨/环氧复合材料

MrI引导聚焦超声消融治疗局限性中危前列腺癌：一项II期临床试验的早期结果

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国际医学放射学杂志 2021年第3期44卷 355-356页

作者： S.Ghai A.Finelli K.Corr r.chan S.Jokhu X.Li 董龙春

摘要为了减少全腺体治疗的副作用,临床上显著的局限性前列腺癌病人可以接受MrI引导下局部治疗。目的探讨MrI引导下靶向高强度聚焦超声治疗临床显著的中危前

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Human endogenous retrovirus type-W and multiple sclerosis–related smoldering neuroinflammation

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Neural regeneration research 2025年第3期20卷 813-814页

作者： Joel Gruchot Laura reiche Andrew chan robert Hoepner Patrick Küry Department of Neurology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neurology InselspitalBern University Hospital and University of BernBernSwitzerland

Introduction to human endogenous retrovirus type-W(HErV-W): Genomic inheritance from the past includes retroviral sequences that have been stably incorporated into our genomes and account for up to 8% of human DNA.

关键词： endogenous inflammation Human

Coarse to Fine: The role of Severe Plastic Deformation in Advancing Titanium-Based Medical Implants - A Comprehensive review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana r Mihajlović Bojan I Međo Ivana Lj Cvijović-Alagić Veljko r Djokić Faculty of Technology and Metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča Institute of Nuclear Sci-ences-National Institute of the republic of Serbia University of Belgrade11001BeogradSerbia Innovation Centre of the Faculty of Technology and Metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(SPD)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the SPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPD techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in medicine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the SPD process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties

Emerging potential of progranulin-dependent SorCS2 signaling in healthy and diseased nervous systems

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Neural regeneration research 2025年第9期20卷 2591-2593页

作者： Alena Salasova Anders Nykjær Danish research Institute of Translational Neuroscience DANDrITE-Nordic EMBL Partnership for Molecular Medicine and Centre of Excellence PROMEMODepartment of BiomedicineAarhus UniversityAarhusDenmark

The formation of the mammalian nervous system and its maturation into sensory,motor,cognitive,and behavioral circuits is a complex process that begins during early embryogenesis and lasts until young *** neurodevelopm... 详细信息

关键词： progr jointly CS2

Security Strategy of Digital Medical Contents Based on Blockchain in Generative AI Model

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Computers, Materials & Continua 2025年第1期82卷 259-278页

作者： Hoon Ko Marek r.Ogiela Division of Computer Science and Engineering Sunmoon UniversityAsan31460Republic of Korea AGH University of Krakow Cryptography and Cognitive Informatics LaboratoryKrakow30-059Poland

This study presents an innovative approach to enhancing the security of visual medical data in the generative AI environment through the integration of blockchain *** combining the strengths of blockchain and generative AI,the research team aimed to address the timely challenge of safeguarding visual medical *** participating researchers conducted a comprehensive analysis,examining the vulnerabilities of medical AI services,personal information protection issues,and overall security *** multi faceted exploration led to an indepth evaluation of the model’s performance and ***,the correlation between accuracy,detection rate,and error rate was *** analysis revealed insights into the model’s strengths and limitations,while the consideration of standard deviation shed light on the model’s stability and performance *** study proposed practical improvements,emphasizing the reduction of false negatives to enhance detection rate and leveraging blockchain technology to ensure visual data integrity in medical *** blockchain to generative AI-created medical content addresses key personal information protection *** utilizing the distributed ledger system of blockchain,the research team aimed to protect the privacy and integrity of medical data especially medical *** approach not only enhances security but also enables transparent and tamperproof ***,the use of generative AI models ensures the creation of novel medical content without compromising personal information,further safeguarding patient *** conclusion,this study showcases the potential of blockchain-based solutions in the medical field,particularly in securing sensitive medical data and protecting patient *** proposed approach,combining blockchain and generative AI,offers a promising direction toward more robust and secure medical content *** research and advancements

关键词： Digitalmedical content medical diagnostic visualization security analysis generativeAI blockchain vulnerability pattern recognition

Antisense oligonucleotides provide optimism to the therapeutic landscape for tauopathies

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Neural regeneration research 2025年第3期20卷 803-804页

作者： Glenn A.Harris Lauren r.Hirschfeld rainwater Charitable Foundation Fort WorthTXUSA

Tauopathies are a group of neurodegenerative diseases characterized by abnormal metabolism of the misfolded tau protein. Tau is encoded by the microtubule-associated protein tau gene(MAPT) and can be classified as either 3-repeat(3r) or 4-repeat(4r) based on the number of repeat domains from alternative splicing of exon 10 of the MAPT gene.

关键词： tau metabolism diseases