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Association of glutathione peroxidase-1 （GPx-1） rs1050450 Pro198Leu and Pro197Leu polymorphisms with cardiovascular risk：a meta-analysis of ob-servational studies

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Journal of Geriatric Cardiology 2014年第2期11卷 141-150页

作者： Jun-Xia ZHANG Zhi-mei WANG Jun-Jie ZHANG Lin-Lin ZHU xiao-fei GAO Shao-Liang CHEN Department of Cardiology Nanjing First Hospital Affiliated to Nanjing Medical University Nanjing Jiangsu Province 210006 China

Objective To clarify the association between rs1050450 polymorphism in Glutathione peroxidase-1 （GPx-1） and the risk of cardi-ovascular diseases （CVD） by performing a meta-analysis of published studies. There is growing evidence from different study types for an association of the GPx-1 polymorphism and cardiovascular outcomes, but observational studies have so far shown inconsistent results. Me-thods Relevant publications were searched through PubMed, Embase database databases and the Cochrane Library. We used odds ratios （ORs） with 95%confidence intervals （CIs） to assess the strength of association under the best genetic model. Both Q statistic and the I2 were used to check heterogeneity. Meta-regression analysis was performed to explore heterogeneity source. Sensitivity analysis, cumulative me-ta-analysis analysis and publication bias were used to test the reliability of the results. Results Data were available from two cohort studies and 8 case-control studies involving 1,430 cases and 3,767 controls. The pooled ORs for overall CVD risk was 1.36 with 95%CI：1.08-1.70 under a co-dominant model, and that for East Asian subgroup was 1.84 （95%CI：1.39-2.43）. Substantial heterogeneity for ORs were de-tected among all the included studies, mainly caused by ethnic differences between East Asian and non-East Asian populations. Although Egger＇s regression test suggested no statistical significant publication bias, Begg＇s funnel plot exhibited obvious asymmetry. The statistical significance disappeared after adjusting for potential publication bias in the overall studies. However, no substantial publication bias was found in the East Asian subgroup. Conclusions GPx-1 gene Pro198Leu and Pro197Leu polymorphisms considerably increased the risk of CVD in the East Asian population. Large-scale investigations are needed to confirm the results in different ethnicities.

关键词： Glutathione peroxidase-1 Cardiovascular diseases Polymorphism Meta-analysis

In vivo observation of cerebral microcirculation after experimental subarachnoid hemorrhage in mice

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Neural Regeneration Research 2018年第3期13卷 456-462页

作者： xiao-mei Yang Xu-hao Chen Jian-fei Lu Chang-man Zhou Jing-yan Han Chun-hua Chen Department of Human Anatomy and Embryology Peking University Health Science Center School of Basic Medical Sciences Peking University Health Science Center Tasly Microcirculation Research Center Peking University Health Science Center

Acute brain injury caused by subarachnoid hemorrhage is the major cause of poor prognosis. The pathology of subarachnoid hemorrhage likely involves major morphological changes in the microcirculation. However, previous studies primarily used fixed tissue or delayed injury models. Therefore, in the present study, we used in vivo imaging to observe the dynamic changes in cerebral microcirculation after subarachnoid hemorrhage. Subarachnoid hemorrhage was induced by perforation of the bifurcation of the middle cerebral and anterior cerebral arteries in male C57/BL6 mice. The diameter of pial arterioles and venules was measured by in vivo fluorescence microscopy at different time points within 180 minutes after subarachnoid hemorrhage. Cerebral blood flow was examined and leukocyte adhesion/albumin extravasation was determined at different time points before and after subarachnoid hemorrhage. Cerebral pial microcirculation was abnormal and cerebral blood flow was reduced after subarachnoid hemorrhage. Acute vasoconstriction occurred predominantly in the arterioles instead of the venules. A progressive increase in the number of adherent leukocytes in venules and substantial albumin extravasation were observed between 10 and 180 minutes after subarachnoid hemorrhage. These results show that major changes in microcirculation occur in the early stage of subarachnoid hemorrhage. Our findings may promote the development of novel therapeutic strategies for the early treatment of subarachnoid hemorrhage.

关键词： nerve regeneration subarachnoid hemorrhage microcirculation disturbance leukocyte adhesion albumin extravasation cerebral blood flow vasoconstriction early brain injury neural regeneration

Microstructure and mechanical properties of Ti-Cu amorphous coating synthesized on pure Cu substrate by mechanical alloying method

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Rare Metals 2020年第10期39卷 1222-1228页

作者： Cheng Chen xiao-mei Feng Yi-fu Shen School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211800China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Mechanical alloying method was applied to fabricate coating with amorphous structure on pure Cu *** microstructure,the phase composition and the mechanical properties including microhardness and wear resistance of the coating were,respectively,characterized and *** results show that the coating is rough but *** has favorable adhesion to the *** coating is made up of an inner composite layer and an outer amorphous *** microhardness and the wear resistance of the pure Cu substrate are improved because of the bilayer *** formation mechanism of the coating was *** as-synthesized coating is considered to be effective to strengthen the surface of pure Cu substrate.

关键词： Coating Amorphous Mechanical alloying Surface reinforcement

Dynamic event-triggered formation control of second-order nonholonomic systems

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Journal of Systems Engineering and Electronics 2023年第2期34卷 501-514页

作者： WANG xiaoyu SUN Sijia xiao Feng YU mei School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

In this paper,the formation control problem of secondorder nonholonomic mobile robot systems is investigated in a dynamic event-triggered ***-triggered control protocols combined with persistent excitation(PE)conditions are *** event-detecting processes,an inactive time is introduced after each sampling instant,which can ensure a positive minimum sampling *** increase the flexibility of the event-triggered scheme,internal dynamic variables are included in event-triggering ***,the dynamic event-triggered scheme plays an important role in increasing the lengths of time intervals between any two consecutive *** addition,event-triggered control protocols without forward and angular velocities are also presented based on approximate-differentiation(low-pass)*** asymptotic convergence results are given based on a nested Matrosov theorem and artificial sampling methods.

关键词： nonholonomic system dynamic event-triggered control consensus-based formation

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Frontiers of physics 2015年第2期10卷 87-90页

作者： Chun Li fei Long Dong-Cheng mei Department of Computer Science Puer College Puer 665000 China Faculty of Science Kunming University of Science and Technology Kunming 650500 China Department of Physics Yunnan University Kunming 650091 China

The effects of correlation between additive and multiplicative noises on the symmetry of an asymmetric bistable system are investigated. The steady-state probability distribution function of the system was calculated by using analytical and numerical methods. Results indicate that i） for the case of positive correlation between noises, as the correlation strength between additive and multiplicative noises, λ, increases, the symmetry of the system is restored; ii） for the case of negative correlation between noises, as the absolute value of λ increases, the symmetry of the system is destroyed; and iii） the analytic prediction agrees well with the stochastic simulation result.

关键词： asymmetry bistable system correlated noises symmetrical characteristic

Determination of Metamizole Sodium by Cyclic Voltammetry Under Microwave Activation

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Chemical Research in Chinese Universities 2010年第4期26卷 537-540页

作者： LI Li-jun CHENG Long-jun CAI Zhuo LAN Su-mei GUO xiao-fei LI Yan-qing Department of Biological and Chemical Engineering Guangxi University of Technology Liuzhou 545006 P. R. China College of Chemistry and Chemical Engineering Guangxi University Nanning 530004 P. R. China

Microwave radiation was applied to the detection of metamizole sodium by cyclic voltammetry. The electrochemical characteristics of metamizole sodium were studied by cyclic voltammetry at GC electrode under microwave radiation and a considerable current enhancement was observed for metamizole sodium in aqueous 0.05 mol/L H2SO4. Under the optional conditions, metamizole sodium was determined in the absence and presence of microwave activation. In the absence of microwave activation cyclic voltammogram of metamizole sodium shows good linear relationship in a concentration range of 8.0×10^-5-1.0×10^-3 mol/L in aqueous 0.05 mol/L H2SO4 with a detection limit of 6.75× 10^-6 mol/L（S/N=3） and the equation of linear regression is Ip=12.973c-0.1905（R^2=0.9996, n=6）; in the presence of 80 W microwave activation cyclic voltammogram of metamizole sodiumin shows good linear relationship in a concentration range of 4.0× 10^-5-1.0×10^-3 mol/L in aqueous 0.05 mol/L H2SO4 with a detection limit of 4,41 × 10^-6 mol/L（S/N=3） and the equation of linear regression is Ip=25.107c-0.1193（R^2=0.9973, n=7）. The current in the presence of 80 W microwave activation increases to about 2 orders of magnitude compared with that in the absence of microwave activation. The proposed method in the presence of microwave activation showed high selectivity and sensitivity, and the sampling of the disposal method is simple. The method was verified by the determination of Metamizole Sodium tablet with satisfactory results.

关键词： Microwave Metamizole sodium Cyclic voltammetry

Response of the Dominant Modes of Atmospheric Circulation in the Northern Hemisphere to a Projected Arctic Sea Ice Loss in 2007

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Journal of Ocean University of China 2019年第3期18卷 589-595页

作者： FAN Tingting HUANG fei ZHOU xiao Key Laboratory of Physical Oceanography Ocean University of China Qingdao 266100 China Laboratory for Ocean and Climate Dynamics Pilot National Laboratory for Marine Science and Technology (Qingdao) Qingdao 266100 China Ningbo Collaborative Innovation Center of Nonlinear Harzard System of Ocean and Atmosphere Ningbo University Ningbo 315211 China Department of Meteorology and International Pacific Research Center University of Hawaii Honolulu 96822 USA

This study revisits the Arctic sea ice extent(SIE) for the extended period of 1979-2015 based on satellite measurements and finds that the Arctic SIE experienced three different periods: a moderate sea ice decline period for 1979-1996, an accelerated sea ice decline period from 1997 to 2006, and large interannual variation period after 2007, when Arctic sea ice reached its tipping point reported by Livina and Lenton(2013). To address the response of atmospheric circulation to the lowest sea ice conditions with a large interannual variation, we investigated the dominant modes for large atmospheric circulation responses to the projected 2007 Arctic sea ice loss using an atmospheric general circulation model(ECHAM5). The response was obtained from two 50-yr simulations: one with a repeating seasonal cycle of specified sea ice concentration for the period of 1979-1996 and one with that of sea ice conditions in 2007. The results suggest more occurrences of a negative Arctic Oscillation(AO) response to the 2007 Arctic sea ice conditions, accompanied by an North Atlantic Oscillation(NAO)-type atmospheric circulation response under the largest sea ice loss, and more occurrences of the positive Arctic Dipole(AD) mode under the 2007 sea ice conditions, with an across-Arctic wave train pattern response to the largest sea ice loss in the Arctic. This study offers a new perspective for addressing the response of atmospheric circulation to sea ice changes after the Arctic reached the tipping point in 2007.

关键词： Arctic sea ice loss Arctic Oscillation Arctic Dipole atmospheric response

Human Health Risk Assessment Model of Organic Pollution in Groundwater:Shijiazhuang Industrial Zone

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1508-1517页

作者： YANG mei fei Yuhong JU Yiwen LI Huaqi Key Laboratory of Computational Geodynamics of Chinese Academy of Sciences College of Earth Science Graduate University of Chinese Academy Sciences Beijing 100049 China The Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences （CAGS） Shijiazhuang 050061 China Institute of Geology Chinese Academy of Geological Sciences Beijing 10003 7 China

In this study, a risk-based management model is developed and applied to an industrial zone. The models proposed by the United States Environmental Protection Agency and Han Bing have been improved by adding a residual ratio of volatile organic compounds （VOC） after boiling and deleting the related parameters in half-life. Using this improved model, an integrated process was used to assess human health risk level in the study area. Compared with water quality analysis, the results highlight the importance of applying an integrated approach for decision making on risk levels and water protection. The results of this study demonstrated that：（1） Compared with these permissible level standards in China （GB 3838-2002） and National Primary Drinking Water Regulations of the United States, the residents＇ daily life had not been affected by the groundwater in this area （except for relative bad water quality of HB3-4 and HB3-6）; （2） The typical detected organic contaminants of all groundwater samples were chloroform, carbon tetrachloride, trichloroethylene and tetrachloroethene, and the pollution sources were mainly industrial sources by preliminary investigations; （3） As for groundwater, the non-carcinogenic risk values of all samples do not exceed the permissible level of 1.0 and the carcinogenic risk values are relatively lower than the permissible level of 1.00E-06 to 1.00E-04; （4） Drinking water pathway of trichloroethylene and tetrachloroethylene mainly contribute to increasing the health risk of residents＇ in study areas; （5） In terms of non-carcinogenic risk and carcinogenic risk, the health risk order for drinking water pathway and dermal contact pathway was： drinking water pathway 〉 dermal contact pathway.

关键词： groundwater pollution organic contaminants residual rate assessment model human health risk

ENSO Frequency Asymmetry and the Pacific Decadal Oscillation in Observations and 19 CMIP5 Models

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Advances in Atmospheric Sciences 2018年第5期35卷 495-506页

作者： Renping LIN fei ZHENG xiao DONG International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology

Using observational data and the pre-industrial simulations of 19 models from the Coupled Model Intercomparison Project Phase 5（CMIP5）, the El Ni o（EN） and La Ni a（LN） events in positive and negative Pacific Decadal Oscillation（PDO） phases are examined. In the observational data, with EN（LN） events the positive（negative） SST anomaly in the equatorial eastern Pacific is much stronger in positive（negative） PDO phases than in negative（positive） phases. Meanwhile,the models cannot reasonably reproduce this difference. Besides, the modulation of ENSO frequency asymmetry by the PDO is explored. Results show that, in the observational data, EN is 300% more（58% less） frequent than LN in positive（negative）PDO phases, which is significant at the 99% confidence level using the Monte Carlo test. Most of the CMIP5 models exhibit results that are consistent with the observational data.

关键词： ENSO frequency asymmetry Pacific Decadal Oscillation decadal variation Monte Carlo method CM1P5