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Microstructural Evolution of Localized Shear Bands Induced during Explosion in Ti-6Al-4V Alloy

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Journal of Materials Science & Technology 2003年第5期19卷 385-387页

作者： YongboXU M.A.Mevers ShenyangNationalLaboratoryforMaterialsScience InstituteofMetalResearchChineseAcademyofSciencesShenvang110016China DepartmentofMechanicalandAerospaceEngineering UniversityofCaliforniaSanDiegoLaJollaCA920930-0411USA

Microstructures of the localized shear bands generated during explosion with a thick-walled cylinder specimen in Ti-6AI-4V alloy, were characterized by TEM and SEM. The results show that the twinning is a major mode of deformation, and the distortion-free grains in the bands with the size of 10μm in diameter were proposed to be the re-crystallization during dynamic explosion. The further observations show that the α→α2 phase transformation may occur in the bands, and this kind of transformation could be confirmed by its dark field image and electron diffraction analysis. Analysis shows that there is specified orientation between the α and α2 Phases.

关键词： Shear localization Ti-alloy Phase-transformation Twinning

Corner block list representation and its application with boundary constraints

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Science in China(Series F) 2004年第1期47卷 1-19页

作者： HONGXianlong MAYuchun DONGSheqin CAIYici Chung-KuanCheng GUJun DepartmentofComputerScienceandTechnology TsinghuaUniversityBeijing100084China DepartmentofComputerScienceandEngineering UniversityofCaliforniaSanDiegoLaJollaCA92093-0114USA DepartmentofComputerScience ScienceandTechnologyUniversityofHongKong

Floorplanning is a critical phase in physical design of VLSI circuits. The stochastic optimization method is widely used to handle this NP-hard problem. The key to the floorplanning algorithm based on stochastic optimization is to encode the floorplan structure properly. In this paper, corner block list (CBL)-a new efficient topological representation for non-slicing floorplan-is proposed with applications to VLSI floorplan. Given a corner block list, it takes only linear time to construct the floorplan. In floorplanning of typical VLSI design, some blocks are required to satisfy some constraints in the final packing. Boundary constraint is one kind of those constraints to pack some blocks along the pre-specified boundaries of the final chip so that the blocks are easier to be connected to certain I/O pads. We implement the boundary constraint algorithm for general floorplan by extending CBL. Our contribution is to find the necessary and sufficient characterization of the blocks along the boundary represented by CBL. We can check the boundary constraints by scanning the intermediate solutions in linear time during the simulated annealing process and fix the corner block list in case the constraints are violated. The experiment results are demonstrated by several examples of MCNC benchmarks and the performance is remarkable.

关键词： floorplan corner block list simulated annealing boundary constraints.

Genetic approach to track neural cell fate decisions using human embryonic stem cells

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Protein & Cell 2014年第1期5卷 69-79页

作者： Xuemei Fu Zhili Rong Shengyun Zhu Xiaocheng Wang Yang Xu Blue B. Lake Shenzhen Children's Hospital Shenzhen 518026 China Section of Molecular Biology Division of Biological Sciences University of California San Diego 9500 Gilman Drive LaJolla CA 92093-0322 USA

With their capability to undergo unlimited self-renewal and to differentiate into all cell types in the body, human embryonic stem cells （hESCs） hold great promise in human cell therapy. However, there are limited tools for easily identifying and isolating live hESC-derived cells. To track hESC-derived neural progenitor cells （NPCs）, we applied homologous recombination to knock-in the mCherry gene into the Nestin locus of hESCs. This facilitated the genetic labeling of Nestin positive neural progenitor cells with mCherry. Our reporter system enables the visualization of neural induction from hESCs both in vitro （embryoid bodies） and in vivo （ter- atomas）. This system also permits the identification of different neural subpopulations based on the intensity of our fluorescent reporter. In this context, a high level of mCherry expression showed enrichment for neural progenitors, while lower mCherry corresponded with more committed neural states. Combination of mCherry high expression with cell surface antigen staining enabled further enrichment of hESC-derived NPCs. These mCherry＊ NPCs could be expanded in culture and their differentiation resulted in a down-regulation of mCherry consistent with the loss of Nestin expression. Therefore, we have developed a fluorescent reporter system that can be used to trace neural differentiation events of hESCs.

关键词： Nestin knock-in human embryonic stemcells neural progenitor cells

Alteration of β-secretase traffic by the receptor tyrosine kinase signaling pathway- a new mechanism for regulating Alzheimer's β-amyloid production

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Cell Research 2007年第5期17卷 385-386页

作者： Yun-Wu Zhang Huaxi Xu, Center for Neuroscience and Aging, Burnham Institute for Medical Research, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA. xuh@burnham. org CenterforNeuroscienceandAging BurnhamInstituteforMedicalResearch10901N.TorreyPinesRd.LaJollaCA92037USA

The receptor tyrosine kinases (RTKs) are a family of cellsurface proteins with diverse functions in proliferation, dif-ferentiation or cell-cell communication. When a specific li-gand binds to its cognate receptor, a conformational changeof this receptor due to the ligand-receptor interaction willlead to activation of the intrinsic tyrosine kinase residing inthe intracellular domain of the receptor. The activation ofthis tyrosine kinase is essential for transducing the signals toa cascade of its downstream molecules that eventually causerelated physiological responses [1]. For example, binding ofnerve growth factor (NGF) to its receptor TrkA is essentialfor the proper development, patterning, and maintenanceof the mammalian nervous system. This ligand and recep-tor interaction will lead to the formation of a crab-shapedhomodimeric TrkA structure [2], and the subsequent activa-tion of its intrinsic RTK will cause auto-phosphorylationof its own intracellular tyrosine residues. PhosphorylatedTrkA receptors recruit and increase the phosphorylationof PLC-γ and Shc, which leads to activation of either thePI3K/Akt pathway or Ras/raf/ERK pathway. In the brainOf Alzheimer's disease (AD) patients, alterations of nervegrowth factor (NGF) and its receptor TrkA have beenreported to associate with AD pathogenesis [3]. However,the underlying mechanisms remain elusive.

关键词： BACE amyloid production NGF Alteration of a new mechanism for regulating Alzheimer’s secretase traffic by the receptor tyrosine kinase signaling pathway TrkA RTK

New insights into the pathogenesis and treatment of non-viral hepatocellular carcinoma:a balancing act between immunosuppression and immunosurveillance

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Precision Clinical Medicine 2018年第1期1卷 21-28页

作者： Michael Karin Laboratory of Gene Regulation and Signal Transduction UC San Diego School of MedicineDepartment of Pharmacology9500 Gilman DriveLaJollaCA92093USA

Hepatocellular carcinoma(HCC)is one of the leading causes of cancer-related deaths *** initiates as a consequence of chronic liver damage and inflammation caused by hepatitis B and C virus infections,excessive alcohol con sumption,or non-alcoholic fatty liver disease(NAFLD).Until recently,no effective treat-ments for advanced HCC were available and the 5-year survival rate had remained below 8%for many *** insights into the mechanisms that drive the development of NAFLD-related HCC indicate that loss of T-cell-mediated immunosurveillance plays a cardinal role in tumor growth and malignant progression,in addition to previously identifhed inflammation-driven compensatory *** completed groundbreaking clinical studies have shown that treatments that restore antitumor immunity represent a highly effective therapeutic option for approximately 20%of advanced HCC *** the causes of inflammation-driven immunosuppression and immune system dysfunction in the 80%of patients who fail to reignite antitumor immunity despite treatment with checkpoint inhibitors should lead to further and even more dramatic improvements in HCC immunotherapy.

关键词： inflammation immunity treatment

Gravitational Waves Background, as Well as Some UFO, FRB and Supernova Flares, Are Due to Compressibility of the Spacetime (CoST)

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第1期10卷 67-70页

作者： Evgeny A. Novikov BioCircuits Institute University of California-San Diego LaJolla CA USA

The recently observed gravitational wave background is explained in terms of the quantum modification of the general relativity (Qmoger). Some UFO, FRB and supernova flares also can be explained in terms of Qmoger.

关键词： Gravitational Wave Background Quantum Modification of the General Relativity Compressibility of the Spacetime (CoST)

Dynamic Patterns of Gene Expression Additivity and Regulatory Variation throughout Maize Development

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Molecular Plant 2019年第3期12卷 410-425页

作者： Peng Zhou Candice N.Hirsch Steven P.Briggs Nathan M.Springer Department of Plant and Microbial Biology University of MinnesotaSaint PaulMN 55108USA Department of Agronomy and Plant Genetics University of MinnesotaSaint PaulMN 55108USA Division of Biological Sciences University of CaliforniaSanDiegoLaJollaCA92093USA

Gene expression variation is a key component underlying phenotypic variation and heterosis. Transcriptome profiling was performed on 23 different tissues or developmental stages of two maize inbreds, B73 and Mo17, as well as their hybrid. The obtained large-scale datasets provided opportunities to monitor the developmental dynamics of differential expression, additivity for gene expression, and regulatory variation. The transcriptome can be divided into .30 000 genes that are expressed in at least one tissue of one in bred and an additional ~10 000 “silent” genes that are not expressed in any tissue of any genotype, 90% of which are non-syntenic relative to other grasses. Many (.74%) of the expressed genes exhibit differential expression in at least one tissue. However, the majority of genes with differential expression do not exhibit consistent differential expression in different tissues. These genes often exhibit tissue-specific differential expression with equivalent expression in other tissues, and in many cases they switch the directionality of differential expression in different tissues. This suggests widespread variation for tissue-specific regulation of gene expression between the two maize inbreds B73 and Mo17. Nearly 5000 genes are expressed in only one parent in at least one tissue (single parent expression) and 97% of these genes are expressed at mid-parent levels or higher in the hybrid, providing extensive opportunities for hybrid complementation in heterosis. In general, additive expression patterns are much more common than non-additive patterns, and this trend is more pronounced for genes with strong differential expression or single pare nt expressi on. There is relatively little evidence for non-additive expression patterns that are maintained in multiple tissues. The analysis of allele-specific expression allowed classification of cis. and trans-regulatory variation. Genes with c/s-regulatory variation often exhibit additive expression and tend

关键词： maize gene expression heterosis differential expression non-additive expression allele-specific expression

Guard Cell Signaling Dynamics and Rapid Chip-based Cloning of Ion Accumulation Mutants

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Acta Genetica Sinica 2004年第9期31卷 1001-1002页

作者： JulianI.Schroeder JimingGong DavidWaner TomoakiHorie JuneM.Kwak IzumiMori NathalieLeonhardt GethynAllen Zhen-MingPei ErwinGrill YoshiyukiMurata JaredYoung CellandDevelopmentalBiologySection DivisionofBiologicalSciencesUniversityofCaliforniaSanDiegoLaJollaCA920930116USA DepartmentofBiology UniversityofMarylandCollegeParkMD20742USA DepartmentofBiology DukeUniversityDurhamNC27708USA TechnicalUniversity Arcisstr.2180290MunichWeihenstephanGermany

Guard cells have been developed as a model system for dissecting hormone,ion channel and calcium signal transduction in response to physiological stimuli. Abscisic acid causes elevations in the cytosolic Ca^2+ concent... 详细信息

关键词：保卫细胞突变体染色体组信号动力学克隆植物

A multifunctional battery module design for electric vehicle

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Journal of Modern Transportation 2017年第4期25卷 218-222页

作者： MengWang LiangliangZhu AnhV.Le DanielJ.Noelle YangShi YingZhong FengHao XiChen YuQiao Department of Structural Engineering University of California–San DiegoLaJollaCA92093-0085USA Columbia Nanomechanics Research Center Department of Earthand Environmental EngineeringColumbia UniversityNewYorkNY10027USA Program of Materials Scienceand Engineering University of California–SanDiegoLaJollaCA92093USA

Reducing the overall vehicle weight is an efficient,system-level approach to increase the drive range of electric vehicle,for which structural parts in auto-frame may be replaced by battery *** battery modules must be structurally functional,e.g.,energy absorbing,while the battery cells are not necessarily loading–*** designed and tested a butterfly-shaped battery module of prismatic cells,which could self-unfold when subjected to a compressive *** guides and frictionless joints were employed to facilitate the large *** resistance to external loading was offered by additional energy absorption *** battery-module behavior and the battery-cell performance were controlled *** simulation verified the experimental results.

关键词： Electric vehicle Battery module Multifunctional Energy absorption