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Organocatalytic enantioselective Michael addition reactions of fluoromalonates with α,β-unsaturated aldehydes

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Science china Chemistry 2010年第1期53卷 135-139页

作者： LI Hao1,JI YaFei2,LI Jian2,ZHANG ShiLei1,YU ChenGuang1 & wang wei1,2 1 Department of Chemistry and Chemical Biology,university of New Mexico,Albuquerque,NM 8713.-0001,USA 2 Department of Pharmaceutical {3.,school of Pharmacy,East china university of Science and Technology,Shanghai 20023.,china 1. Department of Chemistry and Chemical Biology University of New Mexico Albuquerque NM 87131-0001 USA2. Department of Pharmaceutical Sciences School of Pharmacy East China University of Science and Technology Shanghai 200237 China

A new organocatalytic enantioselective Michael addition of α-fluoromalonate to enals has been *** process is efficiently catalyzed by readily available chiral diphenylpyrolinol TES ether under mild reaction condition... 详细信息

关键词： organocatalysis α β-unsaturated aldehydes chiral fluorinated compounds Michael addition

Observer-based robust high-order fully actuated attitude autopilot design for spinning glide-guided projectiles

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Defence Technology（防务技术） 2024年第4期34卷 282-294页

作者： wei wang Yuchen wang Shiwei Chen Yongcang Guo Zhongjiao Shi school of Aerospace Engineering Beijing Institute of TechnologyBeijing 10081China Northwest Industries Group CO. Ltd.Xi'an 710043China

This paper investigates the design of an attitude autopilot for a dual-channel controlled spinning glideguided projectile(SGGP),addressing model uncertainties and external *** on fixed-time stable theory,a disturbance observer with integral sliding mode and adaptive techniques is proposed to mitigate total disturbance effects,irrespective of initial *** introducing an error integral signal,the dynamics of the SGGP are transformed into two separate second-order fully actuated ***,employing the high-order fully actuated approach and a parametric approach,the nonlinear dynamics of the SGGP are recast into a constant linear closed-loop system,ensuring that the projectile's attitude asymptotically tracks the given goal with the desired *** the proposed composite control framework,the ultimately uniformly bounded stability of the closed-loop system is rigorously demonstrated via the Lyapunov *** of the effectiveness of the proposed attitude autopilot design is provided through extensive numerical simulations.

关键词： Spinning glide-guided projectile Attitude control Sliding mode disturbance observer Fixed-time stable theory High-order fully actuated approach

Self-assembled VS_(2) microflowers buffering volume change during charging and discharging towards high-performance zinc ion batteries

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Journal of Materials Science & Technology 2024年第6期173卷 107-113页

作者： Tingsheng wang Wujie Gao Yuanxi Zhao Songcan wang wei Huang Frontiers Science Center for Flexible Electronics Xi’an Institute of Flexible Electronics(IFE)Northwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Flexible Electronics of Zhejiang Province Ningbo Institute of Northwestern Polytechnical UniversityNingbo 315103China school of Materials Science and Engineering Northwestern Polytechnical UniversityXi’an 710072China

VS_(2) has attracted increasing attention as a cathode material for aqueous zinc ion batteries because of its proper large layer spacing,weak interlayer interactions,multiple valence states of V,and excellent electrical conductivity,but its large volume change during charging and discharging leads to poor cycling ***,we report a one-step hydrothermal synthesis of VS_(2) microflowers with proper lamellar spacing,which provides a stable framework for the insertion/deinsertion of zinc ions and enhances the cycling stability,delivering an initial charge capacity of 128.3.mAh g^(-1) at 3.A g^(-1) and maintains a charge capacity of 100.1 mAh g^(-1) after 900 *** addition,the optimized VS_(2) cathode shows specific capacities of 215.7 and 150.5 mAh g^(-1) at the current densities of 0.1 and 2 A g^(-1),respectively,demonstrating that the microflower structure with a high specific surface area and a short diffusion distance also significantly enhances the rate performance.

关键词： Vanadium sulfide Microflower Zinc ion batteries Cathode materials Volume change

Identification and Characterization of a Rat Novel Gene RSEP4 Expressed Specifically in Central Nervous System

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Acta Biochimica et Biophysica Sinica 2004年第7期36卷 501-507页

作者： Xi-Dao wang1,2, Ling-wei KONG1, Zhi-Qin XIE1, Yu-Qiu ZHANG3. Zhi-Xin LIN2, Zhi-Qi ZHAO3.Lei YU4, and Nai-He JING1* 1 Laboratory of Molecular Cell Biology, Laboratory of Stem Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, Chinese Academy of sciences, Graduate school of the Chinese Academy of sciences, Shanghai 20003., china school of Life Science and Biotechnology, 2 Shanghai Jiaotong university, Shanghai 20003., china Institute of Neurobiology, Fudan university, Shanghai 20043., china 3. 4 Department of Cell Biology, Neurobiology and Anatomy, College of Medicine, university of Cincinnati, Cincinnati, Ohio, USA Laboratory of Molecular Cell Biology and Stem Cell Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences Shanghai China

The low-abundantly expressed genes composed the majorities of the mRNAs expressed in the central nervous system (CNS), and were thought to be important for the normal brain functions. Through differential screening a low-abundance cDNA sublibrary with mRNA from neuropathic pain of chronic constriction injury (CCI) model, we have identified a novel rat gene, rat spinal-cord expression protein 4 gene (RSEP4). The total length of RSEP4 cDNA is 2006 bp, with a 501 nucleotide open reading frame (ORF) that encodes a 167 amino acid polypeptide. Northern blot revealed that RSEP4 was expressed specifically in the CNS. In situ hybridization showed that the mRNA of RSEP4 was strongly expressed in the CA1, CA2, CA3. and DG regions of hippocampus, the Purkinje cells of cerebellum, and the small sensory neurons of dorsal horn and large motor neurons of ventral horn of spinal cord. Over-expression of RSEP4-EGFP fusion protein in the human embryonic kidney 293. cells showed that RSEP4 protein was mainly localized in the cell cytoplasm. These results suggest that RSEP4 may play some roles in the CNS.

关键词： central nervous system (CNS) rat Northern blot in situ hybridization

Association between ICU quality and in-hospital mortality of V-V ECMO-supported patients—the ECMO quality improvement action(EQIA)study:a national cohort study in china from 2017 to 2019

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Frontiers of Medicine 2024年第2期18卷 315-326页

作者： wei Cheng Jieqing Chen Xudong Ma Jialu Sun Sifa Gao Ye wang Longxiang Su Lu wang wei Du Huaiwu He Yujie Chen Zunzhu Li Qi Li Jianhua Sun Hongbo Luo Jinbang Liu Guangliang Shan Bing Du Yanhong Guo Dawei Liu Chang Yin Xiang Zhou on behalf of the china National Critical Care Quality Control Center-the ECMO quality improvement action(EQIA)study Department of Critical Care Medicine State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing100730China Information Center Department/Department of Information Management State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalPeking Union Medical College&Chinese Academy of Medical SciencesBeijing100730China Department of Medical Administration National Health Commission of the People’s Republic of ChinaBeijing100044China school of Population Medicine and Public Health Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100730China Department of Epidemiology and Biostatistics Institute of Basic Medicine SciencesChinese Academy of Medical Sciences(CAMS)&School of Basic MedicinePeking Union Medical CollegeBeijing100730China National Institute of Hospital Administration National Health Commission of the People’s Republic of ChinaBeijing100044China 不详

This cohort study was performed to explore the influence of intensive care unit(ICU)quality on in-hospital mortality of veno-venous(V-V)extracorporeal membrane oxygenation(ECMO)-supported patients in *** study involved all V-V ECMO-supported patients in 3.8 of 1700 tertiary hospitals from 2017 to 2019,using data from the National Clinical Improvement System and china National Critical Care Quality Control *** quality was assessed by quality control indicators and capacity *** the 2563.V-V ECMO-supported patients in 3.8 hospitals,a significant correlation was found between ECMO-related complications and *** reintubation rate within 48 hours after extubation and the total ICU mortality rate were independent risk factors for higher in-hospital mortality of V-V ECMO-supported patients(cutoff:1.5%and 7.0%;95%confidence interval:1.05–1.48 and 1.04–1.45;odds ratios:1.25 and 1.23.P=0.012 and P=0.015,respectively).Meanwhile,the V-V ECMO center volume was a protective factor(cutoff of≥50 cases within the 3.year study period;95%confidence interval:0.57–0.83.odds ratio:0.69,P=0.0001).The subgroup analysis of 864 patients in 11 high-volume centers further strengthened these ***,ICU quality may play an important role in improving the prognosis of V-V ECMO-supported patients.

关键词： veno-venous extracorporeal membrane oxygenation in-hospital mortality high-volume centers quality control intensive care unit capacity parameters

Recent progress on the structure of Ser/Thr protein phosphatases

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Science china(Life sciences) 2008年第6期51卷 487-494页

作者： wang BaiJing1,2, ZHANG Peng1 & wei Qun1 1 Department of Biochemistry and Molecular Biology, Beijing Normal university, Beijing Key Laboratory, Beijing 100875,{3. 2 school of Life Science, Changchun Normal university, Changchun 13.03.,{3. 1. Department of Biochemistry and Molecular Biology Beijing Normal University Beijing Key Laboratory Beijing 100875 China 2. school of Life Science Changchun Normal University Changchun 130032 China

PP1, PP2A and PP2B, belonging to the PPP family of Ser/Thr protein phosphatases, participate in regulating many important physiological processes, such as cell cycle control, regulation of cell growth and division regulation, etc. The sequence homology between them is relatively high, and ter- tiary structure is conserved. Because of the complexity of the structure of PP2A and the diversity of its regulatory subunits, its structure is less well known than those of PP1 and PP2B. The PP2A holoen- zyme consists of a heterodimeric core enzyme, comprising a scaffolding subunit and a catalytic sub- unit, as well as a variable regulatory subunit. In this study, the subunit compositions, similarities and differences between the Ser/Thr protein phsphatases structures are summarized.

关键词： Ser/Thr phosphatases subunit composition similarities and differences crystal structure

Greedy is Good:Constrained Non-submodular Function Maximization via Weak Submodularity

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Journal of the Operations Research Society of china 2024年第3期12卷 627-648页

作者： Ma-Jun Shi wei wang school of Statistics Xi’an University of Finance and EconomicsXi’an710100ShaanxiChina school of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049ShaanxiChina

The widely used greedy algorithm has been recently shown to achieve near-optimal theoretical guarantees for the problems of constrained monotone non-submodular function maximization,with competitive performances in *** this paper,we investigate the problems of maximizing monotone non-submodular set functions under three classes of independent system constraints,including p-matroid intersection constraints,p-extendible system constraints and p-system *** prove that the greedy algorithm yields an approximation ratio ofγ/p+γfor the former two problems,andξγ/p+ξγfor the last problem,which further has been improved toγ/p+γ,whereγ,ξdenote the submodularity ratio and the diminishing returns ratio of set function *** addition,we also show that the greedy guarantees have a further refinement of for all the problems mentioned above,whereαis the generalized curvatureξ/p+αγof set ***,we show that our greedy algorithm does yield competitive practical performances using a variety of experiments on synthetic data.

关键词： Non-submodular function p-matroid intersection p-extendible system p-system Greedy algorithm

Electronic Structure of Doped Trans-Polyacetylene

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Wuhan university Journal of Natural sciences 2002年第1期7卷 51-53页

作者： Ren Da-zhi 1,2, Zhuang wei 2, wang Jun 2 1. Wuhan university Journals Press,Wuhan 43.072,Hubei,{3. 2. school of Physics and Technology, Wuhan university, Wuhan 43.072,Hubei,{3. Wuhan university Journals Press Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Wuhan university School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Wuhan university School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The behavior of electronic structures of doped trans-polyacetylene is revealed by a simple method. (C24H26)+n is used to simulate p-type doped trans-polyacetylene at various doping concentrations. The electronic structure is calculated, by CNDO/2 method. These calculations show that at low doping level, the decrease of electronic energy compensates the increase of elastic energy, thus the bond alternation exists, and the charge carriers are solitons. When doping level is high, the increase of elastic energy is larger than the decrease, of electronic energy, the bond alternation disappears, solitons no longer exist, and polyacetylene is in a metalic state.

关键词： trans polyacetylene CNDO/2 electronic structure doped

Contribution of Root and Microbial Respiration to Soil CO_2 Efflux and Their Environmental Controls in a Humid Temperate Grassland of Japan

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Pedosphere 2009年第1期19卷 31-39页

作者： wang wei FENG Jiang T. OIKAWA Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 （China） school of Urban and Environmental sciences Northeast Normal University Changchun 130024 （China） Institute of Biological sciences University of Tsukuba Tsukuba Ibaraki 305-8572 （Japan）

Soil CO2 efflux, root mass, and root production were investigated in a humid temperate grassland of Japan over a growing season （Apr. to Sep.） of 2005 to reveal seasonal changes of soil CO2 efflux, to separate the respective contributions of root and microbial respiration to the total soil CO2 efttux, and to determine the environmental factors that control soil respiration. Minimal microbial respiration rate was estimated based on the linear regression equations between soil CO2 effiux and root mass at different experimental sites. Soil CO2 efflux, ranging from 4.99 to 16.29 μmol CO2 m^-2 s^-1, depended on the seasonal changes in soil temperature. The root mass at 0-10 cm soil depth was 0.82 and 1.27 kg m^-2 in Apr. and Sep., respectively. The root mass at 0-10 cm soil depth comprised 60% of the total root mass at 0-50 cm soil depth. The root productivity at 0-3. cm depth varied from 8 to 180 g m^-2 month^-1. Microbial and root respiration rates ranged from 1.3. to 5.51 and 2.72 to 12.06μmol CO2 m^-2 s^-1, respectively. The contribution of root respiration to the total soil CO2 efflux averaged 53., ranging from 3.% to 72%. The microbial respiration rate was exponentially related to soil temperature at 10 cm depth （R^2 = 0.9400, P = 0.002, n = 6）, and the root respiration rate was linearly related to the root production at 0-3. cm depth （R2 = 0.6561, P = 0.042, n = 6）.

关键词： grasslands microbial respiration root production root respiration