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Capillary electrophoresis with electrochemiluminescence detection for the analysis of quinolone drugs and pharmacokinetics study

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Chinese Chemical Letters 2008年第8期19卷 962-964页

作者： Yan Ming Liu jun Tao Cao hui wang College of Chemistry and Chemical Engineering Xinyang Normal University Xinyang 464000 China

A novel method for the determination of two quinolone drugs norfloxacin （NOR） and levofloxacin （LVX） was described by capillary electrophoresis with electrochemiluminescence detection. The good relationship （r ≥ 0.9991） between peak area and concentration of analytes was established over two orders of magnitude. The limits of detection （LOD, S/N = 3） in standard solution are 4.8 × 10^-7 mol/L for NOR and 6.4 × 10^-7 mol/L for LVX, respectively. The limits of quantitation （LOQ, S/N = 10） in real human urine samples are 1.2 × 10^-6 mol/L for NOR and 1.4 × 10^-6 mol/L for LVX, respectively. The present method was successfully applied to the determination of NOR and LVX in human urine and the studv of oharmacokinetics of NOR.

关键词： Capillary electrophoresis Electrochemiluminescence detection Quinolone drugs Urine analysis Pharmacokinetics

Extreme spring cold spells in North China during 1961–2014 and the evolving processes

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Atmospheric and Oceanic Science Letters 2018年第5期11卷 432-437页

作者： Ya-Li ZHU hui-jun wang Tao wang Dong GUO Nansen-Zhu International Research Centre Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Climate Change Research Centre Chinese Academy of Sciences

This study presents the major features of extreme spring cold spells(ESCS)in North China during 1961–2014 and the evolving *** an ESCS,northern Eurasia is controlled by large-scale positive SLP anomalies and an anomalous anticyclone that continuously transport northern cold air to North China,causing significant,persistent,lower-than-normal daily *** fact,these positive SLP and anticyclonic wind anomalies begin to appear over northwestern Europe about 10 days prior to the *** anticyclonic wind anomalies keep moving southeastward and expand to the west of Lake Baikal until two days before the ***,the center of the anomalous low-level anticyclone moves over Lake Baikal,inducing northerly wind anomalies that transport cold air into North *** the following days,as the positive SLP anomalies weaken,the anomalous anticyclone and related northerly winds appear to wane,and the ESCS gradually comes to an *** results may prove meaningful for the prediction and early warning of ESCSs.

关键词： Spring cold spell North China spring temperature extreme weather

Epidemics of overweight and obesity among growing childhood in China between 1997 and 2009： Impact of Family Income, Dietary Intake, and Physical Activity Dynamics

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Chinese Medical Journal 2015年第14期128卷 1879-1886页

作者： Chang Su Bing Zhang You-Fa wang Xiao-Fang Jia Hong Xue hui-jun wang Department of Public Health Nutrition and Nutrition Policy National Instiute for Nutrition and Health Chinese Center for Disease Control and Prevention Beijing 100050 China System-oriented Global Childhood Obesity Intervention Program Department of Epidemiology and Environmental Health School of Public Health and Health Professions University at Buffalo State University of New York New York USA

Background： Obesity has become a major health problem among children and adolescents worldwide. This study aimed to examine the trends of overweight and obesity among childhood in China and assess their associations with family income, dietary intake, and physical activity （PA） between 1997 and 2009. Methods： Two waves of cross-sectional data of Chinese children and adolescents aged 7-17 years from the China Health and Nutrition Survey were used. Weight and height were measured following standardized procedures. Dietary intake was assessed by 3 consecutive 24-h recalls. Childhood overweight and obesity were defined using the International Obesity Task Force-recommended body mass index cut-offs. Multivariate linear regression analysis was used to examine the associations of family income with diet intakes and PA. Multivariate logistic regression analysis was conducted to assess the associations of overweight and obesity with family income, dietary intake, and PA. Results： The prevalence of childhood overweight and obesity increased from 12.6% in 1997 to 22.1% in 2009, particularly in the medium- and high-family income groups, which increased by 102.7% and 90.3%, respectively. Higher fat intake （% energy）, and moderate and vigorous PA were significantly associated with overweight and obesity in final model （odds ratio [OR] = 1.01, 95% confidence interval [CI]： 1.00-1.02, P = 0.004; and OR = 0.99, 95% CI： 0.98-1.00, P = 0.036, respectively）. Conclusions： The prevalence of overweight and obesity among Chinese children and adolescents has increased between 1997 and 2009. Reducing fat intake and increasing PA may help obesity prevention.

关键词： Adolescent Child Dietary Intake Income Obesity Overweight Physical Activity

An independent but not identically distributed bit error model for heavy-tailed wireless channels

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第1期14卷 42-49页

作者： Jia LU Wei YANG jun-hui wang Bao-liang LI Wen-hua DOU School of Computer National University of Defense Technology Navy Academy of Armament

The error patterns of a wireless channel can be represented by a binary sequence of ones(burst) and zeros(run),which is referred to as a *** surveys have shown that the run length distribution of a wireless channel is an intrinsically heavy-tailed *** models to characterize such features have to deal with the trade-off between complexity and *** this paper,we use an independent but not identically distributed(inid) stochastic process to characterize such channel behavior and show how to parameterize the inid bit error model on the basis of a *** proposed model has merely two parameters both having intuitive meanings and can be easily figured out from a *** with chaotic maps,the inid bit error model is simple for practical use but can still be deprived from heavy-tailed distribution in *** results demonstrate that the inid model can match the trace,but with fewer *** then propose an improvement on the inid model to capture the 'bursty' nature of channel errors,described by burst length *** theoretical analysis is supported by an experimental evaluation.

关键词： Trace Heavy-tailed Independent but not identically distributed (inid) Bit error model Bursty

A non-uniform grid approach for high-resolution flood inundation simulation based on GPUs

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Journal of Hydrodynamics 2021年第4期33卷 844-860页

作者： jun-hui wang Jing-ming Hou Jia-hui Gong Bing-yao Li Bao-shan Shi Min-peng Guo Jian Shen Peng Lu State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China Xi’an University of TechnologyXi’an710048China CAUPD Beijing Planning and Design Beijing100044China China Power Construction Group Co.LTDNorthwest Engineering Corporation LimitedXi’an710048China

In view of the frequent occurrence of floods due to climate change, and the fact that a large calculation domain, with complex land types, is required for solving the problem of the flood simulations, this paper proposes an optimized non-uniform grid model combined with a high-resolution model based on the graphics processing unit (GPU) acceleration to simulate the surface water flow process. For the grid division, the topographic gradient change is taken as the control variable and different optimization criteria are designed according to different land types. In the numerical model, the Godunov-type method is adopted for the spatial discretization, the TVD-MUSUL and Runge-Kutta methods are used to improve the model’s spatial and temporal calculation accuracies, and the simulation time is reduced by leveraging the GPU acceleration. The model is applied to ideal and actual case studies. The results show that the numerical model based on a non-uniform grid enjoys a good stability. In the simulation of the urban inundation, approximately 40%–50% of the urban average topographic gradient change to be covered is taken as the threshold for the non-uniform grid division, and the calculation efficiency and accuracy can be optimized. In this case, the calculation efficiency of the non-uniform grid based on the optimized parameters is 2–3 times of that of the uniform grid, and the approach can be adopted for the actual flood simulation in large-scale areas.

关键词： Non-uniform grid high-resolution model Godunov-type flood simulation graphics processing unit(GPU)acceleration

Identification of hydrovolcanism and its significance for hydrocarbon reservoir assessment: A review

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Journal of Palaeogeography 2018年第4期7卷 346-362页

作者： Ben-Zhong Xian Yan-Xin He Hua-Peng Niu jun-hui wang Jian-Ping Liu Zhen wang College of Geosciences China University of Petroleum (Beijing) State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum (Beijing)

Investigations of modern volcanic eruptions have demonstrated that ancient volcanic eruptions widely involved water,which was thus named as hydrovolcanic eruptions. Hydrovolcanisms are distinctive in many aspects, such as dynamics,eruptive pattern, texture and structure of rock, and vesicularity. First, normal sediments covered directly by volcanic rocks are the indicators of eruption environments. In addition, microfeatures, special structures, lithofacies or facies associations,and geochemical index of volcanic rocks can also provide significant evidences. Moreover, perlitic texture, quenching fragmentation, surface feature, cementation type, vesicularity, and pillow structure, parallel bedding, large-scale low-angle cross-bedding, antidune cross-bedding of pyroclast are keys to indicating hydrovolcanisms. Clearly,these marks are not equally reliable for identifying eruption environments, and most of them are effective and convincible in limited applications only. For explosive eruptions, the most dependable identification marks include quenching textures, vesicularity in pyroclasts and special large-scale cross-bedding. However, for effusive eruptions,useful indicators mainly include pillow structure, peperite and facies associations. Condensation rate of magma,exsolution of volatile affected by eruptive settings and magma—water interaction, and quenching in hydrovolcanisms have an influence on formation and scale of primary pores, fractures and their evolution during diagenetic ***, this review provides systematic identification marks for ancient hydrovolcanisms, and promotes understanding of the influence of eruptive environments on hydrocarbon reservoirs of volcanic rocks in oil-gas bearing sedimentary basins.

关键词： Hydrovolcanism Volcanic reservoir Eruption environment Hydrocarbon reservoir Oilgas bearing sedimentary basin

HIRA Gene is Lower Expressed in the Myocardium of Patients with Tetralogy of Fallot

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Chinese Medical Journal 2016年第20期129卷 2403-2408页

作者： Zhao-Ru Ju hui-jun wang Xiao-Jing Ma Duan Ma Guo-Ying Huang Pediatric Cardiovascular Center Children's Hospital of Fudan UniversityShanghai 201102China Laboratory of Congenital Heart Disease Shanghai Key Laboratory of Birth DefectsShanghai 201102China

Background：The most typical cardiac abnormality is conotruncal defects （CTDs） in patients with 22q11 deletion syndrome （22q11DS）.HIRA （histone cell cycle regulator） gene,as one of the candidate genes located at the critical region of 22q11DS,was reported as possibly relevant to CTD in animal *** study aimed to analyze the level of expression of the HIRA gene in tetralogy of Fallot （TOF） patients and the potential DNA sequence variations in the promoter ***：The messenger RNA （mRNA） expression was examined with quantitative real-time polymerase chain reaction in 39 myocardial tissues of the right ventricular outflow tract （RVOT） from TOF patients and 4 myocardial tissues of RVOT from noncardiac death *** protein expression was detected using immunohistochemistry in 12 TOF patients and 4 controls.A total of 100 TOF cases and 200 healthy controls were recruited for DNA ***：The mRNA and protein expressions of the HIRA gene in the myocardium of the TOF patients were both significantly lower as compared to the controls （P 〈 0.05）.Five single nucleotide polymorphisms （SNPs）,including g.4111A〉G （rs1128399）,g.4265C〉A （rs4585115）,g.4369T〉G （rs2277837）,g.4371C〉A （rs148516780）,and g.4543T〉C （rs111802956）,were found in the promoter region of the HIRA *** were no significant differences of frequencies in these SNPs between the TOF patients and the controls （P 〉 0.05）.Conclusion：The abnormal lower expression of the HIRA gene in the myocardium may participate in the pathogenesis of TOF.

关键词： Congenital Heart Defects Gene Expression HIRA Single Nucleotide Polymorphism Tetralogy of Fallot

Links between winter dust over the Tibetan Plateau and preceding autumn sea ice variability in the Barents and Kara Seas

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Advances in Climate Change Research 2022年第6期13卷 896-908页

作者： Chao XU Jie-Hua MA Jian-Qi SUN Chao YOU Yao-Ming MA hui-jun wang Tao wang Climate Change Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China CMA Earth System Modeling and Prediction Centre(CEMC) China Meteorological AdministrationBeijing 100081China Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Key Laboratory of Meteorological Disaster(KLME) Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China College of Environment and Ecology Chongqing UniversityChongqing 400044China Land-Atmosphere Interaction and Its Climatic Effects Group State Key Laboratory of Tibetan Plateau Earth System and Resources Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Earth and Planetary Sciences University of Chinese Academy of ScienceBeijing 100049China Center for Pan-third Pole Environment Lanzhou UniversityLanzhou 730000China

The Tibetan Plateau(TP)is characterized by heavily local dust activities,however,the mechanism of interannual variations of winter dust frequency over the TP remain poorly *** studies showed the autumn Arctic sea ice could significantly influence the winter climate over *** autumn sea ice affects winter dust activity over the TP or not?Here,we used an integrated surface database to investigate possible mechanisms for interannual variability in the frequency of winter dust events above the *** variability,which is thought to be mainly caused by local dust emissions,shows significant correlations with sea ice concentration(SIC)in the Barents and Kara Seas during the preceding *** Barents-Kara SIC is accompanied by reduced snow depth over northern Eurasia between autumn and winter,which can enhance the Eurasian mid-latitude westerly jet *** strengthening increases the cyclogenesis and occurrence of strong surface wind speeds in winter,especially over the *** addition,a lower SIC is closely associated with reduced precipitation and snow cover in late autumn and winter over the TP,which in turn enhances warming of the land surface and reduces the area of frozen *** anomalies in atmospheric circulation patterns and local surface conditions promote dust events above the TP during *** ensemble means of Atmospheric Model Intercomparison Project experiments from Phase 6 of the Coupled Model Inter-comparison Project and the Community Atmosphere Model version 4 can generally reproduce the atmospheric circulation anomalies associated with decreased Barents-Kara *** study reveals the crucial effect that SIC anomalies in the Barents and Kara Seas have on winter dust activities over the TP.

关键词： Winter dust frequency Tibetan Plateau Sea ice concentration Barents and Kara Seas Snow anomalies

Effects of α-adrenoreceptor antagonists on apoptosis and proliferation of pancreatic cancer cells in vitro

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World Journal of Gastroenterology 2008年第15期14卷 2358-2363页

作者： Su-Gang Shen Dong Zhang Heng-Tong Hu jun-hui Li Zheng wang Qing-Yong Ma Department of Hepatobiliary and Pancreas Surgery The First Affiliated Hospital Medical College Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China

AIM: To discuss the expression of α-adrenoreceptors in pancreatic cancer cell lines PC-2 and PC-3 and the effects of α1- and α2-adrenoreceptor antagonists, yohimbine and urapidil hydrochloride, on the cell lines in vitro. METHODS: We cultured the human ductal pancreatic adenocarcinoma cell lines PC-2 and PC-3 and analyzed the mRNA expression of α1- and α2-adrenergic receptors by reverse transcription polymerase chain reaction (RT-PCR). The effects of yohimbine and urapidil hydrochloride on cell proliferation were assessed by 3-(4,5-dimethylthiasol-2-yl)- 2,4,-diphenyltetrazolium bromide (MTT) assay. Apoptosis was detected using the terminal deoxyribonucleotidyl transferase (TdT)-mediated biotin-16-dUTP nick-end labeling (TUNEL) assay and flow cytometry (FCM). RESULTS: PC-2 expressed mRNA in α1- and α2- adrenoreceptors. MTT assays showed that urapidil hydrochloride had no effect on PC-3 cell lines. However, exposure to urapidil hydrochloride increased DNA synthesis in PC-2 cell lines as compared to the control group. PC-2 cell lines were sensitive to both drugs. The proliferation of the 2 cell lines was inhibited by yohimbine. Cell proliferation was inhibited by yohimbine via apoptosis induction. CONCLUSION: The expression of α1- and α2- adrenoreceptors is different in PC-2 and PC-3 cell lines, which might be indicative of their different functions. The α2-adrenoceptor antagonist, yohimbine, can inhibit theproliferation of both cell lines and induce their apoptosis, suggesting that yohimbine can be used as an anticancer drug for apoptosis of PC-2 and PC-3 cells.

关键词： Alpha-adrenoreceptor Pancreatic cancer Yohimbine Urapidil hydrochloride