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Gene×environment interaction in major depressive disorder

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World Journal of Clinical Cases 2021年第31期9卷 9368-9375页

作者： Ming-Zhe Zhao xu-sheng Song Jing-Song Ma Bio-X Institutes Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders(Ministry of Education)Shanghai Jiao Tong UniversityShanghai 200240China Tianjin Medical University Cancer Institute and Hospital Tianjin Medical UniversityTianjin 300060China Institute of Advanced Technology Westlake Institute for Advanced StudyHangzhou 310024Zhejiang ProvinceChina School of Engineering Westlake UniversityHangzhou 310024Zhejiang ProvinceChina

Major depressive disorder(MDD)is a multifactorial disorder,where multiple susceptibility genes interact with environmental factors,predisposing individuals to the development of the *** this article,we reviewed different gene×environment interaction(G×E)studies shifting from a candidate gene to a genome-wide *** environmental factors,childhood adversities and stressful life events have been suggested to exert crucial impacts on ***,the diathesis-stress conceptualization of G×E has been challenged by the differential susceptibility ***,we summarized several limitations of G×E studies and suggested how future G×E studies might reveal complex interactions between genes and environments in MDD.

关键词： Major depressive disorder Gene×environment interaction Diathesis-Stress model Differential susceptibility Theory Stressful life events Childhood adversities

Systematic energy-balanced cooperative transmission scheme in wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2012年第6期19卷 14-18页

作者： YAO Li-ping LI Xi JI Hong xu Quan-sheng School of Telecommunication Engineering Beijing University of Posts and Telecommunications

Energy efficiency is a critical issue in wireless sensor networks （WSNs）. In order to minimize energy consumption and balance energy dissipation throughout the whole network, a systematic energy-balanced cooperative transmission scheme in WSNs is proposed in this paper. This scheme studies energy efficiency in systematic view. For three main steps, namely nodes clustering, data aggregation and cooperative transmission, corresponding measures are put forward to save energy. These measures are well designed and tightly coupled to achieve optimal performance. A half-controlled dynamic clustering method is proposed to avoid concentrated distribution of cluster heads caused by selecting cluster heads randomly and to get high spatial correlation between cluster nodes. Based on clusters built, data aggregation, with the adoption of dynamic data compression, is performed by cluster heads to get better use of data correlation. Cooperative multiple input multiple output （CMIMO） with an energy-balanced cooperative cluster heads selection method is proposed to transmit data to sink node. System model of this scheme is also given in this paper. And simulation results show that, compared with other traditional schemes, the proposed scheme can efficiently distribute the energy dissipation evenly throughout the network and achieve higher energy efficiency, which leads to longer network lifetime span. By adopting orthogonal space time block code （STBC）, the optimal number of the cooperative transmission nodes varying with the percentage of cluster heads is also concluded, which can help to improve energy efficiency by choosing the optimal number of cooperative nodes and making the most use of CMIMO.

关键词： energy efficiency dynamic clustering cooperative MIMO data aggregation wireless sensor networks

Joint user pairing and power allocation in uplink virtual MIMO with imperfect CSI

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The Journal of China Universities of Posts and Telecommunications 2013年第3期20卷 32-36页

作者： YAO Li-ping xu Quan-sheng LI Xi JI Hong School of Telecommunication Engineering Beijing University of Posts and Telecommunications

User pairing strategy for virtual multi-input multi-output （VMIMO） has been widely studied to improve system throughput, but most studies are based on perfect channel state information （CSI） and uniform power allocation. However, perfect CSI is very difficult or even impossible to obtain in practical system. Moreover power allocation has significant impact on algorithm performance. Therefore, in this paper, a low-complex joint user pairing and power allocation algorithm based on aggressive discrete stochastic optimization and Lagrangian dual solution is proposed for uplink VMIMO with imperfect CSI. Simulation results show that the proposed algorithm can achieve desirable throughput performance, and restrict inter-user interference （IUI） efficiently.

关键词： VMIMO user pairing power allocation I151

Dissolutive wetting process and interfacial characteristic of molten Sn–17Bi–0.5Cu alloy on copper substrate

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Rare Metals 2013年第6期32卷 537-543页

作者： Bing-sheng xu Li-Kun Zang Zhang-Fu Yuan Yan Wu Zhou Zhou Beijing Key Laboratory for Solid Waste Utilization and Management Department of Energy and Resources EngineeringCollege of Engineering Peking University Department of Chemistry School of Chemistry and Biology EngineeringUniversity of Science and Technology Beijing Beijing Key Laboratory for Solid Waste Utilization and Management Department of Energy and Resources Engineering College of Engineering Peking University Beijing Key Laboratory for Solid Waste Utilization and Management Department of Energy and Resources Engineering College of Engineering Peking University

The reactive spreading processes of Sn–17Bi–0.5Cu melt alloy on Cu substrate were studied by sessile drop method in the temperature range of 523–673 *** contact angles between the solder and Cu substrate at different times were recorded with high-resolution CCD digital *** smallest contact angle was observed at623 and 673 *** spreading radius does not increase monotonously with the temperature *** can be attributed to the strong dissolution of Cu substrate into the liquid solder,which hinders the solder from *** line area configuration of the Sn–17Bi–0.5Cu/Cu system was discussed by the description of the equilibrium *** calculated results based on experiments of the tension balances along each of the three interfaces show good agreement with theoretical *** compounds at the Sn–17Bi–0.5Cu/Cu interface are identified as Cu6Sn5adjacent to the solder and Cu3Sn adjacent to the Cu substrate,*** results are of practical interest for composite lead-free solders’preparations and joining of Sn–17Bi–0.5Cu to Cu substrate.

关键词： Lead-free solder Reactive wetting Sessile drop method Interfaces

Resource allocation algorithm in LTE uplink SC-FDMA system for time-varying channel with imperfect channel state information

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The Journal of China Universities of Posts and Telecommunications 2013年第2期20卷 7-11页

作者： xu Quan-sheng LI Xi JI Hong YAO Li-ping Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications

In long term evolution （LTE） uplink single carrier frequency division multiple access （SC-FDMA） system, the restriction that multiple resource blocks （RBs） allocated to a user should be adjacent, makes the resource allocation problem hard to solve. Moreover, with the practical constraint that perfect channel state information （CSI） cannot be obtained in time-varying channel, the resource allocation problem will become more difficult. In this paper, an efficient resource allocation algorithm is proposed in LTE uplink SC-FDMA system with imperfect CSI assumption. Firstly, the resource allocation problem is formulated as a mixed integer programming problem. Then an efficient algorithm based on discrete stochastic optimization is proposed to solve the problem. Finally, simulation results show that the proposed algorithm has desirable system performance.

关键词： SC-FDMA resource allocation imperfect channel state information discrete stochastic optimization time-varying channel

Hydrogen storage properties of La1-xPrxMgNi3.6Co0.4（x=0-0.4） alloys with annealing treatment

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Rare Metals 2019年第9期38卷 871-876页

作者： Ting-Ting Zhai sheng xu Tai Yang Ze-Ming Yuan Yang-Huan Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China College of Science Northeastern UniversityShenyang 110819China

The as-cast RE-Mg-Ni-b ased AB2-type La1-xPrxMgNi3.6Co0.4(x=0-0.4)alloys were prepared by vacuum induction melting followed by annealing *** phase composition and structure were characterized by X-ray diffraction(XRD)and scanning electron microscope(SEM).The results show that LaMgNi4 and LaNi5 coexist in as-cast alloys,but only LaMgNi4 is detected in the annealed *** morphology of annealed alloys is more homogeneous than that of as-cast *** gaseous hydrogen storage and electrochemical properties were investigated by pressure-composition isotherm(P-C-T)and electrochemical *** P-C-T curves of annealed alloys show flatter and wider pressure plateaus corresponding to absorption/desorption pressure plateaus of LaMgNi4 *** the maximum hydrogen storage content of annealed alloys is lower than that of as-cast *** consideration of the electrochemical properties,the annealed La0.8Pr0.2MgNi3.6Co0.4alloy exhibits a maximum discharge capacity of354.2 mAh·g-1.

关键词： LaMgNi4 P-C-T Annealing treatment Hydrogen storage properties

Synthesis and insecticidal evaluation of phytoalexin phenalenones derivatives

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Chinese Chemical Letters 2017年第6期28卷 1228-1231页

作者： Ya-Nan Zhang Yi-An Feng Zhong Li xu-sheng Shao Shanghai Key Laboratory of Chemical Biology School of Pharmacy East China University of Science and Technology Shanghai 20037 China

Phenalenone is a kind of defensive compound biosynthesized inside plants in response to the outside attack such as fungus and nematodes.A set of derivatives encompassing structural modifications on the privileged phenalenone scaffold were synthesized through introduction of phenyl and hydroxy!substitutes at 9-positon and 2-position and assessed their insecticidal activities against armyworm（Mythimna separata Walker） and cowpea aphids[Aphis craccivora）.No obvious insecticidal activities of the synthesized compounds were observed against *** of the 9-phenyl and 2-hydroxy substituted phenalenone analogues showed potential activities against cowpea aphids with 33%-41%mortality at 500 mg/L.

关键词： Phenalenones derivatives Insecticidal activities Structural modifications

In situ formed ultrafine metallic Ni from nickel(Ⅱ) acetylacetonate precursor to realize an exceptional hydrogen storage performance of MgH_(2)-Ni-EG nanocomposite

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Journal of Magnesium and Alloys 2023年第9期11卷 3174-3185页

作者： Shaoyang Shen Liuzhang Ouyang Jiangwen Liu Hui Wang xu-sheng Yang Min Zhu School of Materials Science and Engineering and Key Laboratory of Advanced Energy Storage Materials of Guangdong Province South China University of TechnologyGuangzhou510641China China-Australia Joint Laboratory for Energy&Environmental Materials Key Laboratory of Fuel Cell Technology of Guangdong ProvinceGuangzhouGuangzhou510641China Advanced Manufacturing Technology Research Centre Department of Industrial and Systems EngineeringThe Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

It has been well known that doping nano-scale catalysts can significantly improve both the kinetics and reversible hydrogen storage capacity of MgH_(2) . However, so far it is still a challenge to directly synthesize ultrafine catalysts(e.g., < 5 nm), mainly because of the complicated chemical reaction processes. Here, a facile one-step high-energy ball milling process is developed to in situ form ultrafine Ni nanoparticles from the nickel acetylacetonate precursor in the MgH_(2) matrix. With the combined action of ultrafine metallic Ni and expanded graphite(EG), the formed MgH_(2)-Ni-EG nanocomposite with the optimized doping amounts of Ni and EG can still release 7.03 wt.% H_(2) within 8.5 min at 300 ℃ after 10 cycles. At a temperature close to room temperature(50 ℃), it can also absorb 2.42 wt.% H_(2) within 1 h. It can be confirmed from the microstructural characterization analysis that the in situ formed ultrafine metallic Ni is transformed into Mg_(2)Ni/Mg_(2)NiH_4 in the subsequent hydrogen absorption and desorption cycles. It is calculated that the dehydrogenation activation energy of the MgH_(2)-Ni-EG nanocomposite is also reduced obviously in comparison with the pure MgH_(2) . Our work provides a methodology to significantly improve the hydrogen storage performance of MgH_(2) by combining the in situ formed and uniformly dispersed ultrafine metallic catalyst from the precursor and EG.

关键词： Hydrogen storage Magnesium hydride Nickel precursor Size effect Expanded graphite

Log identification method in complex sand reservoirs

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Mining Science and Technology 2009年第4期19卷 531-536页

作者： ZHAO Xiao-liang LIAO Xin-wei CHEN Xi xu sheng-feng xu An-zhu MOE Key Laboratory for Petroleum Engineering China University of Petroleum Beifing 102249 China China Petroleum Logging Co. Ltd. Xi＇ an Shaanxi 710021 China Sinopec International Petroleum Exploration ＆ Production Corporation Beifing 100083 China Research Institute of Petroleum Exploration ＆ Development Beifing 100083 China

In order to obtain effective parameters for complex sand reservoirs,a log evaluation method for relevant reservoir parameters is established based on an analysis in the gas-bearing sandstone with high porosity and low permeability,low porosity and permeability and on various characteristics of log responses to reservoir lithologies and physical properties in the Neopleozoic sand reservoir of the Ordos *** log evaluation method covers the Cook method that is used to evaluate the porosity and oiliness in high porosity and low permeability reservoirs and another method in which the mineral content,derived from geochemical logs,is used to identify formation *** areas have high calcium and low silt content,not uniformly distributed,the results of which show up in the complex formation lithologies and conventional log responses with great *** reliability of the method is verified by comparison with conventional log data and core *** calculation results coincide with the core analytical data and gas tests,which indicate that this log evaluation method is available,provides novel ideas for study of similar complex reservoir lithologies and has some reference value.

关键词： complex formation lithology reservoir parameter evaluation Cook method geochemical element element content mineral constituent lithological identification