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Mutant rs189037 in ataxia-telangiectasia mutated gene had a negative association with metabolic syndrome but not cognitive decline in centenarians

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Genes & Diseases 2024年第3期11卷 106-108页

作者： Long Feng Hongqi Huo Qun Li Tao Yang Yali zhao pei Zhang Ping Ping shihui Fu Department of Anesthesiology Hainan Hospital of Chinese People's Liberation Army General HospitalSanyaHainan 572013China Nuclear Medicine Department Handan Central HospitalHandanHebei056001China Department of Neurosurgery Hainan Hospital of Chinese People's Liberation Army General HospitalSanyaHainan 572013China Department of Oncology Hainan Hospital of Chinese People's Liberation Army General HospitalSanyaHainan 572013China Central Laboratory Hainan Hospital of Chinese People's Liberation Army General HospitalSanyaHainan 572013China School of Life Science Beijing Institute of TechnologyBeijing 100081China General Station for Drug and Instrument Supervision and Control Joint Logistic Support Force of Chinese People's LiberationArmyBeijing 100071China Department of Cardiology Hainan Hospital of Chinese People's Liberation Army General HospitalSanyaHainan 572013China Department of Geriatric Cardiology Chinese People's Liberation Army General HospitalBeijing 100853China

Approximately 20%-25%of adults encounter metabolic syndrome(MetS)worldwide,and MetS is a riskfactorfor cognitive decline(CD)*** with MetS have an 11.48-fold increased incidence of CD compared with those without Mets.^(1) Ataxia-telangiectasia mutated(ATM)gene encodes ATM kinase,which belongs to the phosphatidylinositol 3-hydroxy kinase family.

关键词： ATM development cognitive

Self-twisting for macrochirality from an achiral asterisk molecule with fluorescence-phosphorescence dual emission

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Chinese Chemical Letters 2017年第11期28卷 2151-2154页

作者： hongwei Wua Bin Wu Xiyuan Yu pei zhao Wenbo Chen Liangliang Zhu State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Fudan University Shanghai Key Lab of Polymer and Electrical Insulation School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric Power

Understanding of the role of supramolecular chirality for tuning material optoelectronic properties has been restricted by the limited number of cases. A particular challenge is to impose supramolecular chirality onto multicolor luminescent systems that can emit in aggregation state. Here we present a self- assembly strategy from a well-selected asterisk molecule for generating supramolecular chirality with fluorescence-phosphorescence dual emission. The work takes advantages of （1） achiral chemical structure dependent peculiar self-assembly that can spontaneously undergo symmetry breaking to produce macrochirality, and （2） the assembly process can be monitored by time which due to the crystallization-driven self-assembly by self-twisting, allowing a self-progressing chiral amplification. A multicolor luminescence induced by the fluorescence-phosphorescence dual emission along with such a self-assembly behavior was also observed at a single solution system versus the time. The self-twisting chiral self-assembly fashion provides new prospects for understanding the establishment of nanochirality from achiral molecular building blocks.

关键词： Achiral molecules self-twisting Macrochirality Fluorescence-phosphorescence Dual emission

Investigation of the effect of 2＇-substitution of NMN analogues on CD38 NADase inhibitory activity

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Journal of Chinese Pharmaceutical Sciences 2015年第8期24卷 514-523页

作者： Jianguo Li Fen pei Wenjie Zhu hongwei Jin Yongjuan zhao Liangren Zhang Honcheung Lee Lihe Zhang State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical Sciences Peking University Health Science Center Beijing 100191 China School of Chemical Biology and Biotechnology Peking University Shenzhen Graduate School Shenzhen 518055 China

CD38 is a nicotinamide adenine dinucleotide （NAD）-metabolizing enzyme responsible for catalyzing the synthesis of Ca^2＋ messengers. Its inhibitor plays an important role in probing the regulatory pathway and physiological function of CD38. For clearly understanding the effect of 2＇-substitution of nicotinamide mononucleotide （NMN） analogues on CD38 NADase inhibitory activity, a new kind of NMN analogues with two substituents at C-2＇ was investigated. Molecular dynamics （MD） simulation and quantum chemical calculation were used to investigate the mechanism by which 2＇-substitution affects the inhibitory activity. The results showed that two substituents at C-2＇ interfered the formation of covalent bond between C-1＇ of NMN analogues and CD38. The findings of this study will be helpful for comprehensively clarifying the structure-activity relationships of NMN- related CD38 NADase＇s inhibitor.

关键词： CD38 NMN analogues Structure-activity relationship Molecular modeling

A Novel Location Method for Single-phase Grounding Fault for Distribution Network Based on Transient Technique

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A Novel Location Method for Single-phase Grounding Fault for...

Research on the Mechanism of Heat Transfer in the Process of Solidification of Molten Steel in the Combined Mold

第30届中国控制与决策会议

作者： Peng Ji Yujie pei shihui zhao Chunling Bai Wei Wu Liguo Liang Pin Dong Hongxin Sun Zhi Tang State Grid Liaoning Electric Power Supply Co.Ltd Fushun Power Supply Branch State Grid Liaoning Electric Power Supply Co.Ltd Jinzhou Power Supply Branch State Grid Liaoning Electric Power Supply Co.Ltd

Distribution network usually refers to the rated voltage of 110 KV and below, and the function of direct power supply to users in the power system. The reliability of distribution network power supply directly affects the safety and economy of electricity use. In recent years, with the development of the national economy, the power load has greatly increased. In some areas, the construction of distribution networks cannot keep up with the increase in power load, resulting in power outages and frequent power failures in some regions. At the same time, users are increasingly demanding power quality. Whether the dispatcher or the user is eager to quantify the safety and economic analysis of the distribution network, the accuracy and level of the decision making of the intelligent distribution network dispatcher are improved. Studying the short-circuit fault and single-phase-to-ground fault fast fault location scheme is of great significance to improving the reliability of the distribution network operation. Self-healing is one of the main functions for the safe and reliable operation of smart grids. Reliable detection is the basis for realizing the self-healing function. The probability of a single-phase earth fault in a distribution network is very high because I mostly use it for neutral point grounding in medium-voltage distribution networks and use arc-suppression coils for grounding. When single-phase earthed, it is difficult to find point failures. At present, the small current ground fault line selection technology has been basically mature, and the small current ground fault location technology has achieved good results in the field of transient signals. Based on the transient characteristics of transient components, the single-phase ground fault location technology of power distribution network and the transient characteristics of single-phase grounded neutral distribution network are studied. At the same time, single-phase ground fault detection and cross-sec

关键词： Distribution network Phase-to-ground Fault location Transient component

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Research on the Mechanism of Heat Transfer in the Process of...

The Qitai radio telescope

第二届先进钢铁结构材料国际会议

作者： TAO Hongbiao QIU Shengtao TANG hongwei ZHANG Hui zhao pei(Central Iron and Steel Research Institute Beijing 100081 China)

＜正＞The formation of crystal nucleus can be facilitated by decreasing degree of superheat of molten steel, based on which reducing temperature grads on the front edge of solidified shell can retard the growth of columnar grain in the continuous casting mold so that the proportion of equiaxial grain can be increased. Based on above principle,billets whose proportion of equiaxial crystal are more than 90% have been casted and the heat flux of combined mold has been *** heat transfer character of combined mold and traditional mold has been *** results show that on the same casting conditions the temperature grads on the front edge of solidified shell in the combined mold are smaller than that in the traditional mold at the same height within 0～150 millimeter from the meniscus of molten steel.

关键词： Combined Mould Heat Transfer Temperature Grads Proportion of Equiaxial crystal

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Science China(Physics,Mechanics & Astronomy) 2023年第8期66卷 150-161页

作者： Na Wang Qian Xu Jun Ma Zhiyong Liu Qi Liu Hailong Zhang Xin pei Maozheng Chen Richard N.Manchester Kejia Lee Xingwu Zheng Hans J.Kärcher Wulin zhao hongwei Li Dongwei Li Martin Süss Matthias Reichert Zhongyi Zhu Congsi Wang Mingshuai Li Rui Li Ning Li Guljaina Kazezkhan Wenming Yan Gang Wu Lang Cui Ming Zhang Haitao Li Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Xinjiang Key Laboratory of Radio Astrophysics Urumqi 830011China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China Australia Telescope National Facility CSIRO Space and AstronomyEpping 1710Australia Department of Astronomy Peking UniversityBejing 100871China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Dr.Hans Jirgen Karcher Engineering Office Karben 61184Germany Northwest China Research Institute of Electronic Equipment Xi'an 710065China OHB Digital Connect(MT Mechatronics) Mainz 55130Germany Beijing Institute of Architetural Design Beijing 100045China Guangzhou Instiute of Technology Xidian UniversityGuangzhou 510555 China

This study presents a general outline of the Qitai radio telescope(QTT)***,the site of the telescope,is a county of Xinjiang Uygur Autonomous Region of China,located in the east Tianshan Mountains at an elevation of about 1800 *** QTT is a fully steerable,Gregorian-type telescope with a standard parabolic main reflector of 110 m *** QTT has adopted an umbrella support,homology-symmetric lightweight *** main reflector is active so that the deformation caused by gravity can be *** structural design aims to ultimately allow high-sensitivity observations from 150 MHz up to115 *** satisfy the requirements for early scientific goals,the QTTwill be equipped with ultra-wideband receivers and large field-of-view multi-beam receivers.A multi-function signal-processing system based on RFSo C and GPU processor chips will be *** will enable the QTT to operate in pulsar,spectral line,continuum and Very Long Baseline Interferometer(VLBI)observing *** compatibility(EMC)and radio frequency interference(RFI)control techniques are adopted throughout the system *** QTT will form a world-class observational platform for the detection of lowfrequency(nano Hertz)gravitational waves through pulsar timing array(PTA)techniques,pulsar surveys,the discovery of binary black-hole systems,and exploring dark matter and the origin of life in the *** QTT will also play an important role in improving the Chinese and international VLBI networks,allowing high-sensitivity and high-resolution observations of the nuclei of distant galaxies and gravitational lensing *** astrometric observations will also contribute to improving the accuracy of the celestial reference ***,the QTT will be able to support future space activities such as planetary exploration in the solar system and to contribute to the search for extraterrestrial intelligence.

关键词： radio telescope radio astronomy observation receiver RFI

河北坝上地区2000-2019年植被绿度动态及其土地利用/覆被变化归因分析

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水土保持通报 2021年第6期41卷 345-352页

作者：王彦芳裴宏伟赵超河北地质大学河北省农业干旱遥感监测国际联合研究中心/河北省高校生态环境地质应用技术研发中心河北石家庄050031 河北建筑工程学院市政与环境工程系河北张家口075000 河北省气象科学研究所河北石家庄050021

[目的]分析河北坝上地区植被绿度变化及土地利用/覆被变化,旨在为区域生态建设和京津冀生态环境支撑区的建设提供科学参考,为土地合理利用及生态环境保护提供决策支持。[方法]以MODIS MOD13Q1 NDVI遥感数据为数据源,结合Landsat土地利... 详细信息

[目的]分析河北坝上地区植被绿度变化及土地利用/覆被变化,旨在为区域生态建设和京津冀生态环境支撑区的建设提供科学参考,为土地合理利用及生态环境保护提供决策支持。[方法]以MODIS MOD13Q1 NDVI遥感数据为数据源,结合Landsat土地利用数据,使用线性倾向估计分析了2000—2019年坝上地区植被绿度的年际变化趋势,并定量分析了土地利用/覆被变化对其的影响。[结果]①河北坝上地区主要生长季(4—10月)多年平均植被绿度整体上呈现坝东高,坝西低的空间格局,且林地>草地>耕地;②研究时段坝上地区生长季NDVI最大值和平均值均呈现明显的增加趋势,速率分别为0.063/10 a和0.044/10 a,植被绿度显著提升区域比例为60%~83%;③结合土地利用变化定量解析植被绿度年际变化发现,研究时段,坝上地区植被绿度变化量中,耕地的贡献率为50.51%~57.22%,其次,林地和草地的贡献率分别为21.73%~28.62%和14.41%~15.07%,水域、建设用地和未利用地的总贡献率在6%左右。[结论]2000—2019年,坝上地区植被绿度增加趋势中耕地的贡献最大,但贡献率呈下降趋势,林地和草地的贡献逐渐增加。

关键词：坝上地区 MODIS 植被绿度 NDVI 土地利用/覆被变化河北省

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对称阀控非对称作动缸动态特性研究

机床与液压 2016年第13期44卷 140-143页

作者：赵洪伟冯建民段世慧张革命中国飞机强度研究所全尺寸飞机结构静力/疲劳实验室陕西西安710065

在大型飞机结构强度试验中,伺服阀和作动缸的选取是通过额定流量、负荷量以及行程来实现的,而二者的动态特性未给予充分考虑,可能导致伺服阀和作动缸不匹配,严重影响阀控缸的动态性能。为此,文中建立了伺服阀和非对称缸的传递函数,仿真... 详细信息

在大型飞机结构强度试验中,伺服阀和作动缸的选取是通过额定流量、负荷量以及行程来实现的,而二者的动态特性未给予充分考虑,可能导致伺服阀和作动缸不匹配,严重影响阀控缸的动态性能。为此,文中建立了伺服阀和非对称缸的传递函数,仿真分析二者动态特性对阀控非对称缸动态行为的影响,绘出伺服阀和作动缸伯德图。仿真结果显示:截止频率是阀控缸匹配特性的量度;保持阀控缸工作性能的最低截止频率为10 Hz。

关键词：飞机结构强度试验动态特性非对称缸频率响应

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阀控非对称缸摩擦力对缸内压力的影响

机床与液压 2015年第17期43卷 173-175页

作者：赵洪伟段世慧杨胜春滕申科中国飞机强度研究所陕西西安710065

为研究在大型飞机结构疲劳试验中缸内摩擦力对阀控非对称缸压力的影响,建立了非对称缸压力的数学模型,分析计算了阀控非对称缸换向时压力受摩擦力影响发生的变化。利用AMESim仿真软件对系统进行了仿真得到了相应的压力变化曲线,验证了... 详细信息

为研究在大型飞机结构疲劳试验中缸内摩擦力对阀控非对称缸压力的影响,建立了非对称缸压力的数学模型,分析计算了阀控非对称缸换向时压力受摩擦力影响发生的变化。利用AMESim仿真软件对系统进行了仿真得到了相应的压力变化曲线,验证了理论推导。仿真结果表明:摩擦力使得非对称缸的压力突变值增加且压力曲线出现振荡,该研究为大型飞机结构疲劳试验中使用的非对称缸的设计提供参考。

关键词：非对称作动缸压力突变摩擦力 AMESim