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Optimal index shooting policy for layered missile defense system

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Journal of Systems Engineering and Electronics 2020年第1期31卷 118-129页

作者： LI Longyue fan Chengli xing Qinghua XU Hailong ZHAO Huizhen Air and Missile Defense College Air Force Engineering University

In order to cope with the increasing threat of the ballistic missile(BM)in a shorter reaction time,the shooting policy of the layered defense system needs to be *** main decisionmaking problem of shooting optimization is how to choose the next BM which needs to be shot according to the previous engagements and results,thus maximizing the expected return of BMs killed or minimizing the cost of BMs *** by this,this study aims to determine an optimal shooting policy for a two-layer missile defense(TLMD)*** paper considers a scenario in which the TLMD system wishes to shoot at a collection of BMs one at a time,and to maximize the return obtained from BMs killed before the system *** provide a policy analysis tool,this paper develops a general model for shooting decision-making,the shooting engagements can be described as a discounted reward Markov decision *** index shooting policy is a strategy that can effectively balance the shooting returns and the risk that the defense mission fails,and the goal is to maximize the return obtained from BMs killed before the system *** numerical results show that the index policy is better than a range of competitors,especially the mean returns and the mean killing BM number.

关键词： Gittins index shooting policy layered missile defense multi-armed bandits problem Markov decision process

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自发性高血压幼鼠淋巴微循环自律运动特征

微循环学杂志 2015年第4期25卷 19-24页

作者：盛有明孟凡星赵永刚王冰李爱玲李宏伟修瑞娟中国医学科学院北京协和医学院微循环研究所国际微血管医学研究中心国家卫计委微循环重点实验室北京100005

目的:观察幼龄自发性高血压大鼠(SHR)发病早期淋巴微循环的自律运动特征。方法:手术暴露3周龄雄性SHR(SHR组,n=11)和Wistar大鼠(Wistar组,n=11)肠系膜集合淋巴管,采用活体显微录像设备连续视频录像,使用Vastrack自律运动跟踪技术对视频... 详细信息

目的:观察幼龄自发性高血压大鼠(SHR)发病早期淋巴微循环的自律运动特征。方法:手术暴露3周龄雄性SHR(SHR组,n=11)和Wistar大鼠(Wistar组,n=11)肠系膜集合淋巴管,采用活体显微录像设备连续视频录像,使用Vastrack自律运动跟踪技术对视频录像进行动态测量分析,比较两组大鼠肠系膜集合淋巴管自律运动收缩频率、相对振幅、收缩时长、舒缩时长、收缩振幅、舒张振幅、收缩速度、舒张速度、收缩/舒张时长比、收缩分数和收缩活力指数的差异。结果:SHR组大鼠淋巴微循环自律运动的相对振幅、收缩振幅、舒张振幅、收缩时长、舒张时长、收缩速度、舒张速度和收缩分数较Wistar组大鼠轻度降低,收缩频率、收缩/舒张时长比和收缩活力指数较Wistar组大鼠小幅上升,但差异均无统计学意义(P>0.05)。结论:自发性高血压早期幼鼠集合淋巴管自律运动特征未见显著改变,提示其淋巴微循环尚未发生明显功能紊乱。

关键词：淋巴微循环自律运动自发性高血压大鼠

Bilayer nicorandil-loaded small-diameter vascular grafts improve endothelial cell function via PI3K/AKT/eNOS pathway

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Bio-Design and Manufacturing 2021年第1期4卷 72-86页

作者： Zheng xing Chen Zhao Chunchen Zhang Yubo fan Haifeng Liu Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education School of Biological Science and Medical EngineeringBeijing Advanced Innovation Centre for Biomedical EngineeringBeihang UniversityXue Yuan Road No.37Haidian DistrictBeijing 100191China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China Key Laboratory of Biomedical Engineering of Ministry of Education Zhejiang UniversityHangzhou 310027China Zhejiang Provincial Key Laboratory of Cardio-Cerebral Vascular Detection Technology and Medicinal Effectiveness Appraisal Zhejiang UniversityHangzhou 310027China

For the surgical treatment of cardiovascular disease(CVD),there is a clear and unmet need in developing small-diameter(diameter<6 mm)vascular *** our previous work,sulfated silk fibroin(SF)was successfully fabricated as a potential candidate for preparing vascular grafts due to the great cytocompatibility and ***,vascular graft with single layer is difficult to adapt to the complex internal *** this work,polycaprolactone(PCL)and sulfated SF were used to fabricate bilayer vascular graft(BLVG)to mimic the structure of natural blood *** enhance the biological activity of BLVG,nicorandil(NIC),an FDA-approved drug with multi-bioactivity,was loaded in the BLVG to fabricate NIC-loaded *** morphology,chemical composition and mechanical properties of NIC-loaded BLVG were *** results showed that the bilayer structure of NIC-loaded BLVG endowed the graft with a biphasic drug release *** in vitro studies indicated that NIC-loaded BLVG could significantly increase the proliferation,migration and antioxidation capability of endothelial cells(ECs).Moreover,we found that the potential biological mechanism was the activation of PI3K/AKT/eNOS signaling ***,the results effectively demonstrated that NIC-loaded BLVG had a promising in vitro performance as a functional small-diameter vascular graft.

关键词： Bilayer vascular grafts Nicorandil Sulfated silk fibroin Endothelial cell function PI3K/AKT/eNOS pathway

SnO_(2)/Co_(3)O_(4)nanofibers using double jets electrospinning as low operating temperature gas sensor

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Chinese Physics B 2022年第2期31卷 618-625页

作者： Zhao Wang Shu-xing fan Wei Tang School of Physics and Electronics Shandong Normal UniversityJinan 250358China

SnO_(2)/Co_(3)O_(4)nanofibers(NFs)are synthesized by using a homopolar electrospinning system with double jets of positive polarity electric *** morphology and structure of SnO_(2)/Co_(3)O_(4)hetero-nanofibers are characterized by using field emission scanning electron microscope(FE-SEM),transmission electron microscope(TEM),x-ray diffraction(XRD),and x-ray photoelectron spectrometer(XPS).The analyses of SnO_(2)/Co_(3)O_(4)NFs by EDS and HRTEM show that the cobalt and tin exist on one nanofiber,which is related to the homopolar electrospinning and the crystallization during *** a typical n-type semiconductor,Sn O_(2)has the disadvantages of high optimal operating temperature and poor *** with Sn O_(2),the optimal operating temperature of SnO_(2)/Co_(3)O_(4)NFs is reduced from 350℃to 250℃,which may be related to the catalysis of Co_(2)O_(2).The response of SnO_(2)/Co_(3)O_(4)to 100-ppm ethanol at 250℃is 50.9,9 times higher than that of pure Sn O_(2),which may be attributed to the p–n heterojunction between the n-type Sn O_(2)crystalline grain and the p-type Co_(2)O_(2)crystalline *** nanoscale p–n heterojunction promotes the electron migration and forms an interface *** synergy effects between Sn O_(2)and Co_(2)O_(2),the crystalline grain p–n heterojunction,the existence of nanofibers and the large specific surface area all jointly contribute to the improved gas sensing performance.

关键词： SnO_(2)/Co_(3)O_(4)nanofibers(NFs) homopolar double jets electrospinning gas sensors nanoscale p-n heterojunction

猫杯状病毒CH-JL2分离株对猫的致病性研究

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中国预防兽医学报 2018年第7期40卷 592-595页

作者：刘宏凯伊淑帅李登亮牛江婷王开董浩孟繁星王军政赵艳丽董国英胡桂学吉林农业大学动物科学技术学院吉林长春130118 吉林农业大学生命科学学院吉林长春130118 北京师范大学全球变化与地球系统科学研究院北京100875

为研究猫杯状病毒(FCV)CH-JL2分离株对猫的致病性,本研究采用滴鼻方式分别以10^(8.97)TCID_(50)/mL、10^(7.97)TCID_(50)/mL与10^(6.97)TCID_(50)/mL的病毒液(0.5mL/只)感染6~11周龄健康未免疫中华田园猫,通过对临床症状、体温、排毒情况、组织病理变化以及组织中病毒分布情况的观察与监测,评价其致病性。结果显示,不同滴度的FCV CH-JL2分离株感染猫均可发病,发病率依次为100%、50%与25%,FCV感染5d后,感染猫开始排毒,出现体温升高、鼻眼分泌物增多、口腔溃疡等典型临床症状,但在感染猫的肺脏、心脏、脾脏、气管等全身组织脏器中均未检测到FCV的分布。结果表明CH-JL2分离株不同于FCV VSD株,感染猫后仅可引起上呼吸道感染,不能造成全身感染。本研究为FCV的防制奠定了基础。

关键词：猫杯状病毒 CH—JL2株中华田园猫致病性

Melt extraction and mineralization: A case study from the Shuangjianzishan supergiant Ag-Pb-Zn deposit(208 Mt), Inner Mongolia, NE China

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China Geology 2023年第4期6卷 623-645,I0001-I0003页

作者： meng Dai Guang-sheng Yan Yong-sheng Li Wen-bin Jia fan-yu Qi xing Ju China Aero Geophysical and Remote Sensing Center for Natural Resources China Geology SurveyMinistry of Natural ResourcesBeijing 100083China Chinese Academy of Geological Sciences China Geology SurveyMinistry of Natural ResourcesBeijing 100037China Development and Research Center China Geology SurveyMinistry of Natural ResourcesBeijing 100037China

The supergiant Shuangjianzishan(SJZ) Ag-Pb-Zn deposit is in the southern segment of the Great Hinggan Range(SGHR), northeast China. Previous studies suggest the ore-forming material and fluid originated from the magmatic system, and the mineralization age was consistent with the diagenetic age. However,the relationship between granitic magmatism and mineralization is still unclear in the SJZ. In this study, CH-O-He-Ar and in-situ S-Pb isotope analyses were conducted to determine the sources of ore-forming fluids and metals, which were combined with geochemistry data of SJZ granitoids from previous studies to constrain the relationship between the magmatism and the mineralization. The C-H-O-He-Ar-S-Pb isotopic compositions suggested the SJZ ore-forming material and fluids were derived from a magmatic source, which has mixed a small amount of mantle-derived materials. In addition, the disseminated sulfide from the syenogranite has comparable S-Pb isotopic composition with the sulfide minerals from ore veins,suggesting that the generation of the SJZ ore-forming fluids has a close relationship with the syenogranite magmatism. Combining with the geochemical characters of the syenogranite, the authors proposed that the mantle-derived fingerprint of the SJZ ore-forming fluid might be caused by the parent magma of the syenogranite, which was derived from partial melting of the juvenile lower crust, and underwent the residual melts segregated from a crystal mush in the shallow magma reservoir. The extraction of the syenogranite parent magma further concentrated the fertilized fluids, which was crucial to mineralization of the SJZ Ag-Pb-Zn deposit.

关键词： Ag-Pb-Zn deposit D-O-C-He-Ar isotope In-situ S and Pb isotope analysis Melt extraction Ore-forming fluid Syenogranite Metallogenic belt Mineral exploration engineering Southern Great Hinggan Range

Association between Vitamin D Insufficiency and the Risk for Gestational Diabetes Mellitus in Pregnant Chinese Women

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Biomedical and Environmental Sciences 2012年第4期25卷 399-406页

作者： WANG Ou NIE Min HU Ying Ying ZHANG Kui LI Wei PING fan LIU Jun Tao CHEN Li meng xing Xiao Ping Department of Endocrinology Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Key Laboratory of Endocrinology Ministry of Health Beijing 100730 China Department of Obstetrics& Gynecology Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China Department of Nephrology Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China

Objective To investigate the association between vitamin D deficiency and risk of gestational diabetes rnellitus （GDM） in pregnant Chinese women. Methods A nested case-control study was conducted. Clinical and biochemical data were analyzed for 200 subjects with GDM and 200 subjects with normal glucose tolerance （NGT）. Results The median （interquartile range） serum 25-hydroxyvitamin D （25OHD） levels were 22.39 （17.67, 29.38） and 25.86 （19.09, 34.88） nmol/L in the GDM and NGT groups, respectively. Rates of 25OHD deficiency or insufficiency were significantly higher in the GDM group than in the NGT group. Subjects with 25OHD levels 〈25 nmol/L had a 1.g-fold higher risk of GDM compared with subjects with higher vitamin D levels. In the GDM group, serum 25OHD was independently associated with HbAlc and insulin resistance after adjusting for confounding factors. In the NGT group, serum 25OHD was independently associated with fasting plasma glucose and systolic blood pressure after adjusting for maternal age and other confounding factors. Conclusion 2SOHD insufficiency is very common in Chinese women. Low 25OHD status may be associated with insulin resistance and act as a risk factor for GDM.

关键词： Gestational diabetes mellitus Vitamin D insufficiency Chinese women

A power efficient 1.0625–3.125 Gb/s serial transceiver in 130 nm digital CMOS for multi-standard applications

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Science China(Information Sciences) 2014年第6期57卷 182-191页

作者： HOU ZhongYuan YANG fan LIU JunHua ZHANG xing Key Laboratory of Microelectronic Devices and Circuits Institute of MicroelectronicsPeking University

A power-efficient and low-cost 1.0625–3.125 Gb/s serial transceiver is presented in this paper for Fiber Channel(FC),Peripheral Component Interconnect Express(PCIe),and RapidIO *** support multiple standards with a single low power and low cost design,the transceiver presented here uses a wide swing range source-series-terminated(SST)transmitter(TX),a passive receiver(RX)equalizer,a dual-loop phase locked loop(PLL)and a mixed signal clock and data recovery(CDR)*** proposed SST transmitter also realizes a 3bit 2-tap de-emphasis filter that compensates up to 6 dB on the transmitter,and a passive equalizer that achieves 4 dB transmission in the *** dual-loop PLL with an on-chip regulator is used to generate a low-jitter clock for the TX and CDR’s reference.A CDR with a phase interpolator(PI)is proposed with a mixed signal structure to recover the clock on the RX and it can tolerate a frequency offset of up to 2000 *** transceiver is fabricated in a 130 nm digital CMOS process and occupies an area of 0.8 *** supply voltages of 1.2 V and 3.3 V,the transceiver dissipates 78 mW when compensating for a total loss of 10 dB at3.125 Gb/s.

关键词： serial transceiver multi-standard power efficiency SST CDR

POSS-embedded supramolecular hyperbranched polymers constructed from a 1→7 branching monomer with controllable morphology transitions

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Science China Chemistry 2018年第3期61卷 311-318页

作者： xing Wang Yanyu Yang Linfeng fan Fei Yang Decheng Wu Beijing National Laboratory for Molecular Sciences State Key Laboratory of Polymer Physics & Chemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China College of Materials Science and Engineering Zhengzhou University Zhengzhou 450052 China University of Chinese Academy of Sciences Beijing 100049 China

The research on the supramolecular hyperbranched polymers(SHPs) that combines the advantages of supramolecular polymer and hyperbranched architecture has attracted considerable interests in many applications. Here we demonstrate a simple approach to prepare POSS-embedded supramolecular hyperbranched polymers(POSS-SHPs) with varied morphology and size by controlling monomer concentration and mixed solvents. The SHPs formations can further transfer into the core-shell structured micelles by addition of competitive guests based on the double supramolecular driving forces.

关键词： POSS-embedded polymer supramolecular hyperbranched polymer host-guest interaction morphology transition