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Adaptive modulation for SVD-based MIMO systems with outdated CSI

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 78-83页

作者： YAN Zhi wang wen-bo wang xiao-ting ZHENG Kan Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

The performance of singular value decomposition （SVD）-based multiple-input multiple-output （MIMO） with adaptive modulation （AM） is dependent on the accuracy of the channel state information （CSI） at the transmitter and the receiver. However, for a time-varying channel, the CSI obtained at the transmitter or the receiver is incorrect owing to an inherent delay or error. A typical system employing SVD suffers degradation in capacity when outdated CSI is used to transmit data. This article first addresses the adaptive modulation MIMO system designed under perfect CSI assumption. Based on that, two scenarios of outdated CSI are investigated and analyzed. The effect of imperfect CSI on the system performance is focused on and a simple post processing SNR （pSNR） adjustment design is proposed on AM system in the two scenarios for reducing degradation in average spectral efficiency （ASE）. Simulation results show that these designs provide good performance in an adaptive way, and enable the adaptive MIMO system considerably more to be robust against CSI imperfection.

关键词： MIMO SVD adaptive modulation ohtdated CSI

Effects of polar cortical cytoskeleton and unbalanced cortical surface tension on intercellular bridge thinning during cytokinesis

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Acta Mechanica Sinica 2011年第6期27卷 1081-1090页

作者： Li wang Mei-wen An xiao-Na Li Fang Yang Yang Liu Institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology 030024 Taiyuan China

To probe the contributions of polar cortical cytoskeleton and the surface tension of daughter cells to intercellular bridge thinning dynamics during cytokinesis,we applied cytochalasin D（CD） or colchicine（COLC） in a highly localized manner to polar regions of dividing normal rat kidney（NRK） *** observed cellular morphological changes and analyzed the intercellular bridge thinning trajectories of dividing cells with different polar cortical *** blebbistatin（BS） application was used to obtain cells losing active contractile force *** results show that locally released CD or colchicine at the polar region caused inhibition of cytokinesis before *** treatment at phases after ingression allowed completion of cytokinesis but dramatically influenced the trajectories of intercellular bridge *** single polar cortical actin induced transformation of the intercellular bridge thinning process,and polar cortical tension controlled deformation time of intercellular *** study provides a feasible framework to induce and analyze the effects of local changes in mechanical properties of cellular components on single cellular cytokinesis.

关键词： Cytokinesis Normal rat kidney epithelial cells Intercellular bridge Polar cortical cytoskeleton - Cortical surface tension

Role of nonsteroidal anti-inflammatory drugs in the prevention of post-ERCP pancreatitis:a meta-analysis

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Hepatobiliary & Pancreatic Diseases International 2009年第1期8卷 11-16页

作者： Dai, Hui-Fen wang, xiao-wen Zhao, Kui Zhejiang Univ Sch Med Affiliated Hosp 1 PET Ctr Hangzhou 310003 Zhejiang Peoples R China Zhejiang Univ Sch Med Hangzhou 310058 Zhejiang Peoples R China Zhejiang Univ Sch Med Affiliated Hosp 2 Dept Tradit Chinese Med Hangzhou 310009 Zhejiang Peoples R China

BACKGROUND: The role of prophylactic nonsteroidal anti-inflammatory drugs (NSAIDs) for reduction of pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP) is debated. We performed a meta-analysis of all published randomized controlled trials to evaluate the efficacy of NSAIDs in the prevention of post-ERCP pancreatitis. DATA SOURCES: Searches were conducted in the databases PubMed, EMBASE and the Cochrane Library. Six randomized clinical trials that fulfilled the inclusion criteria and addressed the clinical questions of this analysis were further assessed. Data were extracted by two independent observers according to predetermined criteria. RESULTS: The risk of pancreatitis was lower in the NSAID group than in the placebo, group (OR: 0.46, 95% CI: 0.32 to 0.65, P < 0.0001). Two hours after ERCP, prophylactic administration of NSAIDs was associated with a lower serum amylase level (WMD: -91.09,95% CI: -149.78 to -32.40, P=0.002), but there was no difference in mean 24-hour serum amylase values (WMD: -379.00, 95% CI: -805.75 to 47.76, P=0.08). No deaths or NSAID-related complications were noted. CONCLUSIONS: Prophylactic administration of NSAIDs can reduce the incidence of post-ERCP pancreatitis; this administration in patients undergoing ERCP is recommended. Further randomized controlled trials are required before its introduction into routine care.

关键词： meta-analysis nonsteroidal anti-inflammatory drugs endoscopic retrograde cholangiopancreatography pancreatitis

A possible mechanism of mineral responses to elevated atmospheric CO_2 in rice grains

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Journal of Integrative Agriculture 2015年第1期14卷 50-57页

作者： GUO Jia ZHANG Ming-qian wang xiao-wen ZHANG Wei-jian Institute of Wetland Research Chinese Academy of Forestry Institute of Applied Ecology Nanjing Agricultural University Technology Center of China Tobacco Fujian Industrial Co. Ltd Chinese Academy of Engineering Institute of Crop Sciences Chinese Academy of Agricultural Sciences/Key Laboratory of Crop EcologyPhysiology & ProductionMinistry of Agriculture

Increasing attentions have been paid to mineral concentration decrease in milled rice grains caused by CO2 enrichment, but the mechanisms still remain unclear. Therefore, mineral （Ca, Mg, Fe, Zn and Mn） translocation in plant-soil system with a FACE （Free-air CO2 enrichment） experiment were investigated in Eastern China after 4-yr operation. Results mainly showed that：（1） elevated CO2 significantly increased the biomass of stem and panicle by 21.9 and 24.0%, respectively, but did not affect the leaf biomass. （2） Elevated CO2 significantly increased the contents of Ca, Mg, Fe, Zn, and Mn in panicle by 61.2, 28.9, 87.0, 36.7, and 66.0%, respectively, and in stem by 13.2, 21.3, 47.2, 91.8, and 25.2%, respectively, but did not affect them in leaf. （3） Elevated CO2 had positive effects on the weight ratio of mineral/biomass in stem and panicle. Our results suggest that elevated CO2 can favor the translocation of Ca, Mg, Fe, Zn, and Mn from soil to stem and panicle. The CO2-led mineral decline in milled rice grains may mainly attribute to the CO2-1ed unbalanced stimulations on the translocations of minerals and carbohydrates from vegetative parts （e.g., leaf, stem, branch and husk） to the grains.

关键词： climate change free-air CO2 enrichment (FACE) hidden hunger nutritional quality paddy field rice

Synthesis and Crystal Structure of a One-dimensional Azido-bridged Manganese (II) Compound [Mn(N_3)_2(H_2O)_3·C_6H_(12)N_4]_n

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Chinese Journal of Structural Chemistry 2006年第2期25卷 135-138页

作者： CHEN Hui wang wen-Guo ZHANG xiao-Feng CHEN Chang-Neng LIU Qiu-Tian State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

A new one-dimensional azido-bridged manganese compound has been prepared and structurally characterized by X-ray diffraction. The complex [Mn（N3）2（H2O）3·C6H12N4]n crystallizes in space group Pnma with a = 6.5252 （5）, b = 9.3226（7）, c = 22.2070（15） ,A°, V= 1350.89（17） ,A°^3, Z = 4, Mr = 333.24, Dc = 1.639 g/cm^3, μ = 1.005 mm^-1 and F（000） = 692. The final refinement gave R = 0.0328 and wR = 0.0777 for 1085 observed reflections with I 〉 2σ（I）. The structure contains [Mn（N3）2（H2O）3]n polymeric chains and uncoordinated hexamethylenetetramine （HMTA） molecules with Mn/HMTA molar ratio of 1：1. The Mn atoms are bridged by end-to-end azido ligands to construct one-dimensional zig-zag infinite chains. Each Mn atom is six-coordinated by three N atoms of three azido ligands and three water O atoms, resulting in an octahedral geometry. Extending hydrogenbonding interactions involving water O atoms, azido and HMTA N atoms link the chains and HMTA molecules into a three-dimensional network.

关键词： manganese crystal structure azide coordination polymer

Anti-obesity and Gut Microbiota Modulation Effect of Astragalus Polysaccharides Combined with Berberine on High-Fat Diet-Fed Obese Mice

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Chinese Journal of Integrative Medicine 2023年第7期29卷 617-625页

作者： YUE Shi-jun wang wen-xiao ZHANG Lei LIU Juan FENG Wu-wen GAO Huan TANG Yu-ping YAN Dan Beijing Key Laboratory of Bio-characteristic Profiling for Evaluation of Rational Drug Use Beijing Shijitan HospitalCapital Medical UniversityBeijing100038China Key Laboratory of Shaanxi Administration of Traditional Chinese Medicine for TCM Compatibility Shaanxi University of Chinese MedicineXi’an712046China Department of Pharmacy Beijing Friendship HospitalCaptical UniversityBeijing Institute of Clinical PharmacyBeijing100050China

Objective To investigate whether astragalus polysaccharides(APS)combined with berberine(BBR)can reduce high-fat diet(HFD)-induced obesity in *** Except for normal mice,32 HFD-induced obese mice were randomized into HFD,APS(1,000 mg/kg APS),BBR(200 mg/kg BBR),and APS plus BBR(1,000 mg/kg APS plus 200 mg/kg BBR)groups,*** 6-week treatment(once daily by gavage),the obesity phenotype and pharmacodynamic effects were evaluated by histopathological examination of epididymal fat,liver,and colon using hematoxylin-eosin staining and serum biochemical analyses by an automated chemistry *** feces were collected at the 12 th week,and taxonomic and functional profiles of gut microbiota were analyzed by 16S ribosomal ribonucleic acid(16S rRNA)*** Compared with HFD group,the average body weight of APS plus BBR group was decreased(P<0.01),accompanied with the reduced fat accumulation,enhanced colonic integrity,insulin sensitivity and glucose homeostasis(P<0.05 or P<0.01).Importantly,APS combined with BBR treatment was more effective than APS or BBR alone in improving HFD-induced insulin resistance(P<0.05 or P<0.01).16S rRNA sequence-based analysis of fecal samples demonstrated that APS combined with BBR treatment exhibited a better impact on HFD-induced gut microbiota dysbiosis,exclusively via the enriched abundances of Bacteroides,which corresponded to the large increase of predicted bacterial genes involved in carbohydrate *** APS combined with BBR may synergistically reduce obesity and modulate the gut microbiota in HFD-fed mice.

关键词： Astragalus polysaccharides berberine obesity gut microbiota Bacteroides

Experimental Study on Geometry Characteristics of Turbulent Premixed Flames for Natural Gas/Air Mixtures

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Journal of Thermal Science 2025年第1期34卷 268-282页

作者： ZHENG Weilin wang Qijiao xiao Huahua CHEN xiaoxiao XIE Fan ZENG wen Liaoning Key Lab of Advanced Test Technology for Aerospace Propulsion System Shenyang Aerospace University State Key Laboratory of Fire Science University of science and Technology of China AVIC Shenyang Aircraft Design and Research Institute

In this study,focusing on the geometry characteristics of spherical expanding flame,the turbulent premixed flames of natural gas/air mixtures were investigated in a fan-stirred turbulent *** effects of initial temperature（T=300-400 K）,initial pressure（P=0.1-0.3 MPa）,turbulence intensity（u'=1.0-2.7 m/s）,oxygen volumetric percentage(φ（O2）=15%-21%) and carbon dioxide volumetric percentage(φ（CO2）=0-20%)were delved *** flame profile under the Cartesian coordinate system was derived from the schlieren images taken by the high-speed ***,from both macroscopic and microscopic perspectives,the influence of experimental conditions on the flame geometry characteristics was explored through flame front extraction,wavelet decomposition and network *** results demonstrate that for significant flame wrinkling,changes in species concentrations and turbulence intensity have more pronounced effects on the flame wrinkling *** wrinkling of the flame front maintains a certain degree of similarity,as evidenced by the locally concentrated distribution of the angles of the maximum fluctuation *** disturbance energy under large-scale（D6-D8） disturbances exhibits relatively high values with a similar trend,exerting a significant impact on the geometry characteristics of the flame *** peaks of correlation degree are scattered either with the decomposition scale or the development of flame radius,indicating no linear correlation between different detail ***,the probability distribution of node degrees in key wrinkled regions exhibits different trends with that of large-scale wrinkling and disturbance energy,especially with changes in initial *** occurs because the number of key wrinkles varies based on the perturbation's strength or the region's ***,an increase in the fluctuation frequency of the flame's local radius may not necessarily lead to an increase in the number of key folded regions.

关键词： fan-stirred turbulent combustor geometry characteristics large-scale wrinkling network topology wavelet decomposition

Impact of Life Skills Training to Improve Cognition on Risk of Sexual Behavior and Contraceptive Use among Vocational School Students in Shanghai,China

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Journal of Reproduction and Contraception 2008年第4期19卷 239-251页

作者： Chao-hua LOU xiao-jin wang xiao-wen TU Er-sheng GAO Shanghai Institute of Planned Parenthood Research National Population and Family Planning Key Laboratory of Contraceptive Drugs & Devices Shanghai 200032 China

Objective To evaluate the impact of life skills training that uses participatory teaching method on improving reproductive health cognition of vocational school students of metropolitan, China.Methods Three vocational schools of an urban district in Shanghai were selected as the research sites, with two schools as the intervention groups（group A and group B） and the other as the control（group C）. Group A was provided life skills training with core of reproductive health plus peer education, while group B only provided life skills training. All the second grade students were recruited as the subjects. Baseline surveys were conducted in three schools before the implementation of the intervention, and similar surveys were conducted after two terms of the intervention to test the effectiveness of the intervention. In total, 1 612 subjects, including 810 males and 802 females, were recruited. The effects of the intervention on subjects＇ cognitions on sexual behavior and condom/contraceptive use were analyzed using mixed model with repeated measures.Results From pretest to posttest, there were significant increase of the proportions of perceiving risks in getting pregnant, infecting STDs and HIV, benefits by learning and using condom, and self-efficacy in contraceptive use, and decrease of the proportions of perceiving barriers for condom use in two intervention groups; while few similar changes in the control group. In mixed modeling analysis, interaction effects of group A × time and group B × time were found on the scores of perceived risks （P〈0.000 1）, perceived benefits （P〈0.000 1）, perceived barriers （P=0.001 2for group A and P=0.003 4 for group B）,and perceived self-efficacy （P〈0.000 1）. The significant difference of the effects between two interventions was only observed on perceived benefits （P 〈0.000 1）.Conclusion Life skills training using participatory approaches is effective in improving students＇ reproductive health cognition and could be used as an im

关键词： life skill training participatory method reproductive health cognition vocational school students China

Ambient Particulate Matter Pollution and Hospital Visits for Cardiac Arrhythmia in Beijing,China

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Biomedical and Environmental Sciences 2021年第7期34卷 562-566页

作者： WU Jun Hui WU Yao wang Zi Jing TIAN Yao Hua WU Yi Qun WU Tao wang Meng Ying wang xiao wen wang Jia Ting HU Yong Hua Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Medical Informatics Center Peking UniversityBeijing 100191China

Cardiac arrhythmia is a serious public health problem in many *** studies estimated that 33.5 million people are affected by cardiac arrhythmia worldwide,and this number will continue to grow as society *** improvements in diagnostic and therapeutic interventions in electrophysiology,the disease burden,incidence and prevalence of cardiac arrhythmia continue to increase and have aroused public health *** evidence has indicated that air pollution may be associated with cardiac autonomic nervous *** air pollutants,particulate matter with an aerodynamic diameter of≤2.5μm(PM_(2.5))is considered exert more toxicity than other air pollutants,as it provides a larger surface area and absorbs or condenses more toxic substances per unit mass.

关键词： Cardiac arrhythmia cardiac