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Einstein’s Concept of Clock Synchronization Conflicts with the Second Relativity Postulate

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Journal of Modern Physics 2024年第7期15卷 985-1000页

作者： Steven D. Deines Donatech Corporation Inc. Fairfield Iowa USA

Einstein defined clock synchronization whenever photon pulses with timetags traverse a fixed distance between two clocks with equal time spans ineither direction. Using the second relativity postulate, he found clocksmounted on a rod uniformly moving parallel with the rod’s length cannot besynchronized, but clocks attached to a stationary rod can. He dismissed thisdiscrepancy by claiming simultaneity and clock synchronization were not commonbetween inertial frames, but this paper proves with both Galilean and Lorentztransformations that simultaneity and clock synchronization are preservedbetween inertial frames. His derivation means moving clocks can never besynchronized in a “resting” inertial frame. Ultraprecise atomic clocks intimekeeping labs daily contradict his results. No algebraic error occurred inEinstein’s derivations. The two cases of clocksattached to a rod reveal three major conflicts with the currentsecond postulate. The net velocity between a photon source and detector plusthe “universal” velocity c is mathematically equivalent toEinstein’s clock synchronization method. As the ultraprecise timekeepingcommunity daily synchronizes atomic clocks on the moving Earth withultraprecise time uncertainty well below Einstein’s lowest limit ofsynchronization, the theoretical resolution of the apparent conflict isaccomplished by expanding the second relativity postulate to inc.rporate thenet velocity between the photon source and detector with the emitted velocity c as components of the total velocity c. This means the magnitudeof the total photon velocity can exceed the speed limit (299792458 m/s) set by the standard velocity c. .

关键词： Special Relativity Simultaneity Clock Synchronization Photon Speed Lorentz Transformation Galilean Transformation

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广域保护(稳控)技术的现状及展望

电网技术 2004年第8期28卷 20-25页

作者：蔡运清汪磊 KipMorison PrabhaKundur 周逢权郭志忠美国许继公司 powertech labs inc. 北京许继公司北京100085

在电网保护控制中,稳控系统是基本定位于常规保护及数据采集和监测控制系统/能量管理系统(SCADA/EMS)之间的系统保护控制手段,是互联大电网不可少的保护措施。1965年北美大停电后,开始了这类系统装置的开发应用,到80年代已积累了不少的... 详细信息

在电网保护控制中,稳控系统是基本定位于常规保护及数据采集和监测控制系统/能量管理系统(SCADA/EMS)之间的系统保护控制手段,是互联大电网不可少的保护措施。1965年北美大停电后,开始了这类系统装置的开发应用,到80年代已积累了不少的实际运行经验。各大电网的规划、运行、调度均对这类系统的功能及运行提出了明确的要求。随着计算机技术及通信技术的发展,新一代的稳控技术正在形成,这就是基于广域测量系统及在线动态安全分析的广域保护。广域测量系统已经在北美运行5年以上,而基于广域测量系统的稳定控制及其它应用也逐渐在实际电网中有一些试运行的成果。

关键词：电网电力系统广域保护电压稳定频率稳定控制策略数据采集

MAVS Antagonizes Human Stem Cell Senescence as a Mitochondrial Stabilizer

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Research 2024年第2期2023卷 239-257页

作者： Cui Wang Kuan Yang Xiaoqian Liu Si Wang Moshi Song Juan Carlos Izpisua Belimonte Jing Qu Guang-Hui Liu Weiqi Zhang CAS Key Laboratory of Genomic and Precision Medicine Beijng Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Sino-Danish College University of Chinese Academy of SciencesBeijing 101408China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of Sciences Beijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Bejing 100101China Advanced Innovation Center for Human Brain Protection National Clinical Research Center for Geriatric DisordersXuanwu Hospital Capital Medical UniversityBeijing 100053China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Altos labs Inc.San DiegoCA 94022USA

Mitochondrial dysfunction is a hallmark feature of cellular senescence and organ ***,we asked whether the mitochondrial antiviral signaling protein(MAVS),which is essential for driving antiviral response,also regulates human stem cell *** answer this question,we used CRISPR/Cas9-mediated gene editing and directed differentiation techniques to generate various MAVS-knockout human stem cell *** found that human mesenchymal stem cells(hMSCs)were sensitive to MAVS deficiency,as manifested by accelerated senescence *** uncovered that the role of MAVS in maintaining mitochondrial structural integrity and functional homeostasis depends on its interaction with the guanosine triphosphatase optic atrophy type 1(OPA1).Depletion of MAVS or OPA1 led to the dysfunction of mitochondria and cellular senescence,whereas replenishment of MAVS or OPA1 in MAVS-knockout hMSCs alleviated mitochondrial defects and premature senescence *** together,our data underscore an uncanonical role of MAVS in safeguarding mitochondrial homeostasis and antagonizing human stem cell senescence.

关键词： CRISPR/Cas9 homeostasis Mitochondrial

Novel schemes to generate multi-level modulation formats for ultra-capacity coherent detection transmission systems

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Chinese Optics Letters 2010年第9期8卷 823-830页

作者： Jianjun Yu Xiang Zhou ZTE USA inc. Iselin NJ 08830 USA and also with ZTE Inc. Beijing 100876 China AT&T labs-Research Middletown NJ 07748 USA

We summarize several novel schemes to generate multi-level modulation formats for high capacity transmission system with high spectral efficiency. We show that multi-level 8QAM, 16QAM, 32QAM, and 64QAM （QAM： quatlrature amplitude modulation） optical signals can be generated by commercial optical and electrical devices. Employing these multilevel modulation formats, we have realized PDM-8QAM （PDM： polarization division multiplexing） 32 Tb/s and PDM-36QAM 64-Tb/s signals transmission over 580-and 320-km fibers, respectively.

关键词： Spectrum analyzers

Towards automated statistical partial discharge source classification using pattern recognition techniques

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High Voltage 2018年第3期3卷 162-169页

作者： Hamed Janani Behzad Kordi Department of Electrical and Computer Engineering University of Manitoba75A Chancellor's CircleWinnipegMBCanadaR3T5V6 powertech labs inc. 12388-88 AvenueSurreyBCCanadaV3W 7R7

This study presents a comprehensive review of the automated classification in partial discharge(PD)source identification and probabilistic interpretation of the classification results based on the relationship between the variation of the phase-resolved PD(PRPD)patterns and the source of the *** proposed automated classification system consists of modern,high-performance statistical feature extraction methods and classifier *** application in online monitoring and recognition of the PD patterns is investigated based on their low-processing time and high-performance *** application of modern statistical algorithms and pre-processing methods configured in this automated classification system improves the pattern recognition accuracy of the different PD sources that are suitable to be employed in different high-voltage(HV)insulation *** evaluate the performance of the different combinations of the feature extraction/classier pairs,laboratory setups are designed and built that simulate various types of *** test cells inc.ude three sources of PD in SF6,two sources of PD in transformer oil,and corona in the *** samples for different classes of PD sources are captured under two levels of voltage and two different levels of *** results of this study evaluate the suitability of the proposed classification systems for probabilistic source identification in various insulation ***,of importance to the problem of the PD source identification is to assign a‘degree of membership’to each PRPD pattern,besides assigning a class label to *** of the classifier algorithms studied in this study,such as fuzzy classifiers,are not only able to show high classification accuracy rate,but they also calculate the‘degree of membership’of a sample to a class of *** enables probabilistic interpretation of a new PRPD pattern that is being *** determination of the degree of membership for future PRPD samples allows saf

关键词： pattern membership source

Synthesis of Highly ordered Large Size Mesoporous Silica and Effect of Stabilization as Enzyme Supports in Organic Solvent

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Chemical Research in Chinese Universities 2002年第2期18卷 200-205页

作者： LI Bo Inagaki S Miyazaki C Takahashi H Toyota Central R&D labs. Inc.411YokomichiNagakute choAichi 4801192Japan

FSM 16, MCM 41 and SBA 15 types of hexagonal mesoporous silica with a highly ordered 2 dimensional structure were synthesized by using different silicon sources and surfactants. In the 2 dimensional silicate framework, pore size can be uniformly controlled by the combined use of the surfactants having different alkyl chain lengths and the swelling agents(triisopropyl benzene). The pore diameter of FSM 16 and MCM 41 can be expanded to be 10 nm, SBA 15 to be 15 nm. The crystal regularity was decreased with the inc.ease of the pore diameter. In FSM 16 derived from kanemite(silicon source) and MCM 41 from water glass, their anionic characteristics on the pore wall may be stronger than those of SBA 15 derived from oligomeric tetramethoxysilane(TMOS). We have successfully used FSM 16 and MCM 41 to immobilize the enzyme having cationic residues below isoelectric point. The level of adsorption of enzymes in FSM 16 and MCM 41 was relatively high, but was low in SBA 15 support. The mechanism of enzyme to be adsorbed in mesoporous silica was suggested to be the ionic interactions. In aqueous solutions, horseradish peroxidase(HTP) was immobilized in FSM 16 with 8.9 nm mesopores and the highest loading amount(183 mg/mg FSM) was obtained, but for the FSM 16 of pore diameter 30 nm only an amount of 28 mg/mg FSM was obtained. The catalytic activity in the organic solvent was high when HRP was immobilized in FSM 16 and MCM 41, but it was low in case of SBA 15.

关键词： Mesoporous silica Surfactant Swelling agent Enzyme Activity

Creation of crystal structure reproducing X-ray diffraction pattern without using database

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npj Computational Materials 2023年第1期9卷 946-954页

作者： Joohwi Lee Junpei Oba Nobuko Ohba Seiji Kajita Toyota Central R&D labs. Inc.41-1 YokomichiNagakuteAichi 480-1192Japan

When a sample’s X-ray diffraction pattern(XRD)is measured,the corresponding crystal structure is usually determined by searching for similar XRD patterns in the ***,if a similar XRD pattern is not found,it is tremendously laborious to identify the crystal structure even for *** case commonly happens when researchers develop novel and complex *** this study,we propose a crystal structure creation scheme that reproduces a given XRD *** employed a combinatorial inverse design method using an evolutionary algorithm and crystal morphing(Evolv&Morph)supported by Bayesian optimization,which maximizes the similarity of the XRD patterns between target one and those of the created crystal *** sixteen different crystal structure systems with twelve simulated and four powder target XRD patterns,Evolv&Morph successfully created crystal structures with the same XRD pattern as the target(cosine similarity 99%for the simulated ones and>96%the experimentally measured ones).Furthermore,the present method has merits in that it is an automated crystal structure creation scheme,not dependent on a *** believe that Evolv&Morph can be applied not only to determine crystal structures but also to design materials for specific properties.

关键词： properties crystal structure

A single-nucleus transcriptomic atlas of primate liver aging uncovers the pro-senescence role of SREBP2 in hepatocytes

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Protein & Cell 2024年第2期15卷 98-120页

作者： Shanshan Yang Chengyu Liu Mengmeng Jiang Xiaoqian Liu Lingling Geng Yiyuan Zhang Shuhui Sun Kang Wang jian Yin Shuai Ma Si Wang Juan Carlos Izpisua Belmonte Weiqi Zhang Jing Qu Guang-Hui Liu Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu Hospital Capital Medical UniversityBeijing 100053China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijing 100053China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China Xuanwu Hospital Capital Medical University Beijing 100053China University of Chinese Academy of Sciences Beijing 100049China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China Aging Biomarker Consortium Beijing 100101China Altos labs Inc.San DiegoCA 94022USA

Aging inc.eases the risk ofliver diseases and systemic susceptibility to aging-related ***,cell type-specific changes and the underlying mechanism of liver aging in higher vertebrates remain inc.mpletely ***,we constructed the first single-nucleus transcriptomic landscape of primate liver aging,in which we resolved cell type-specific gene expression fluctuation in hepatocytes across three liver zonations and detected aberrant cell-cell interactions between hepatocytes and niche *** in-depth dissection of this rich dataset,we identifed impaired lipid metabolism and upregulation of chronic inflammation-related genes prominently associated with declined liver functions during *** particular,hyperactivated sterol regulatory element-binding protein(SREBP)signaling was a hallmark of the aged liver,and consequently,forced activation of SREBP2 in human primary hepatocytes recapitulated in vivo aging phenotypes,manifesting as impaired detoxification and accelerated cellular *** study expands our knowledge of primate liver aging and informs the development of diagnostics and therapeutic interventions for liver aging and associated diseases.

关键词： single-nucleus RNA sequencing liver hepatocytes aging senescence SREBP2

Surface Activities of Calix [4]resorcinarenes Bearing Four Hydrophobic Chains and Its Solubilization for Organic Compounds

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Chemical Research in Chinese Universities 2002年第2期18卷 206-210页

作者： LI Bo Yoshifumi KOIDE Kunio ESUMI Toyota Central R&D labs. Inc.411YokomichiNagakuteAichi 4801192Japan Departemnt of Applied Chemistry and Institute of Colloid and Interface Science Science University of Tokyo

Calix resorcinarenes bearing four hydrophobic side chains ( Ar-Rn, Ar-Ph, and Ar-N) orient stably on water oil interface and show high solubilization capacities for organic compounds, such as long chain alcohols, benzene, toluene and dyes. The capacities are high even near the cmc of polyalkylated calix resorcinarenes, but the solubilities of organic compounds(solubilizates) decrease with the inc.ease of the size of the solubilizates. Ar-R 6, with a chain length of six carbons, is the most effective among Ar-R n , Ar-Ph, and Ar-N; 11 fold mol of hexanol is dissolved in 2×10 -3 mol/L Ar-R 6. Moreover, Ar-R n bearing four alkyl side chains solubilizes the chain alcohols of the same chain length mostly. The solubilization capacities are presumably brought by inc.usion in a large cavity of the polyalkylated calix resorcinarenes and by an efficient orientation of the solubilizates.

关键词： Calix resorcinarene Hydrophobic chain Polyalkylate Solubilizate