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The semileptonic decays of B/B_s meson in the perturbative QCD approach:a short review

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Chinese Science Bulletin 2014年第29期59卷 3787-3800页

作者： Zhen-Jun Xiao Ying-Ying Fan wen-fei wang Shan Cheng Department of Physics and Institute of Theoretical Physics Nanjing Normal University Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Institute of High Energy Physics and Theoretical Physics Center for Science Facilities Chinese Academy of Sciences

In this short review,we present the current status about the theoretical and experimental studies for some important semileptonic decays of B=*** firstly gave a brief introduction for the experimental measurements for B=Bs!Peltl;l ml;m mT decays,the BaBar’s ReDT and ReD T anomaly,the P05deviation for B0!K 0ltl *** then made a careful discussion about the evaluations for the relevant form factors in the light-cone QCD sum rule,the heavy quark effective theory,and the perturbative QCD factorization *** using the form factors calculated in the perturbative(pQCD)approach,we then calculate and show the pQCD predictions for the decay rates of many semileptonic decays of B=*** also made careful phenomenological analysis for these pQCD predictions and found,in general,the following points:(a)For all the considered B=Bssemileptonic decays,the next-to-leading order pQCD predictions for their decay rates agree well with the data and those from other different theoretical methods;(b)For ReDT and ReD T,the pQCD predictions agree very well with the data,the BaBar’s anomaly of ReDe TT are therefore explained successfully in the standard model by employing the pQCD approach;and(c)We defined several new ratios Rl;s Dand Rl;s Ds,they may be more sensitive to the QCD dynamics which controls the B=Bs!eDe T;De T sT transitions than the old ratios,we therefore strongly suggest LHCb and the forthcoming Super-B experiments to measure these new ratios.

关键词：微扰QCD 衰变率 BS 介子光锥QCD求和规则实验测量评论 QCD因子化

Semileptonic decays B→D^(*) lυ in the perturbative QCD factorization approach

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Chinese Science Bulletin 2014年第2期59卷 125-132页

作者： Ying-Ying Fan wen-fei wang Shan Cheng Zhen-Jun Xiao Department of Physics and Institute of Theoretical Physics Nanjing Normal University

In this paper,we study the B→D^(*) l-l -ι semileptonic decays and calculate the branching ratios B(B→D^(*) l-l -ι) and the ratios R(D^(*)) and R_D^( l,s) by employing the perturbative QCD(pQCD)factorization *** find that(a)for R(D)and R(D*)ratios,the pQCD predictions are R(D)=0.430-0.026?0.021,R(D*)=0.301±0.013 and agree well with BaBar’s measurements of ReD e?T T;(b)for the newly defined R_D^1 and R_D^s ratios,the pQCD predictions are R_D^l=0.450-0.051+0.064 and R_D^s=0.642-0.070+0.081,which may be more sensitive to the QCD dynamics of the considered semileptonic decays than R(D^(*)) and should be tested by experimental measurements.

关键词： QCD因子化微扰QCD 半轻子衰变量子色动力学实验测量 RDT 分支比预言

Risk of venous thromboembolism in children and adolescents with inflammatory bowel disease: A systematic review and meta-analysis

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World Journal of Gastroenterology 2022年第16期28卷 1705-1717页

作者： Xin-Yue Zhang Hai-Cheng Dong wen-fei wang Yao Zhang Department of Traditional Chinese Medicine The Children’s HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhou 310005Zhejiang ProvinceChina

BACKGROUND A two-to three-fold increased risk of venous thrombotic events(VTE) has been demonstrated in patients with inflammatory bowel disease(IBD) compared to the general population, but less is known about the risk of VTE in child-and pediatric-onset IBD. In recent years, several studies have reported the rising incidence rate of VTE in juvenile patients with IBD, and the related risk factors have been *** To evaluate the risk of VTE in children and adolescents with *** Articles published up to April 2021 were retrieved from Pub Med, Embase, Cochrane Library, Web of Science, Sino Med, CNKI, and WANFANG. Data from observational studies and clinical work were extracted. The outcome was the occurrence of VTE according to the type of IBD. The available odds ratio(OR) and the corresponding 95% confidence interval(CI) were extracted to compare the outcomes. Effect size(P), odds ratio(OR), and 95%CI were used to assess the association between VTE risk and IBD disease. Subgroup analyses stratified by subtypes of VTE and IBD were *** Twelve studies(7450272 IBD patients) were included in the meta-analysis. Child and adolescent IBD patients showed increased VTE risk(P = 0.02, 95%CI: 0.01-0.03). Subgroup analyses stratified by IBD(ulcerative colitis(UC): P = 0.05, 95%CI: 0.03-0.06;Crohn’s disease(CD): P = 0.02, 95%CI: 0.00-0.04) and VTE subtypes(portal vein thrombosis: P = 0.04, 95%CI: 0.02-0.06;deep vein thrombosis: P = 0.03, 95%CI: 0.01-0.05;central venous catheter-related thrombosis: P = 0.23, 95%CI: 0.00-0.46;thromboembolic events: P = 0.02, 95%CI: 0.01-0.03) revealed a significant correlation between VTE risk and IBD. Patients with IBD were more susceptible to VTE risk than those without IBD(OR = 2.99, 95%CI: 1.45-6.18). The funnel plot was asymmetric, suggesting the presence of significant publication bias. Pediatric and adolescent IBD patients have an increased VTE risk. UC and CD patients exhibited a high risk of VTE. The risk of VTE s

关键词： Thromboembolism Children Adolescents Ulcerative colitis Crohn’s disease Meta-analysis

Synthesis of 4-Trifluoromethylated 1,3-Butadienes via Palladium Catalyzed Heck Reaction

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Chinese Journal of Chemistry 2021年第11期39卷 2962-2966页

作者： Yang Li Meng Hao Yu-Chen Chang Yuan Liu wen-fei wang Ning Sun wen-Qing Zhu Ziwei Gao Xi'an Key Laboratory of Textile Chemical Engineering Auxiliaries School of Environmental and Chemical EngineeringXi'an Polytechnic UniversityXi'anShaanxi710048 China School of Chemistry&Chemical Engineering Yan'an UniversityYan'anShaanxi716000 China Xinjiang Normal University UrumchiXinjiang650100 China

1,3-Butadiene plays a key role in modern synthetic chemistry and biochemistry because it is a key intermediate in the synthesis of many drugs.A new and effective method for the synthesis of 4-trifluoromethylated 1,3-butadiene through the fluorinated Heck reaction catalyzed by Pd(0)is *** additives,1-chloro-3,3,3-trifluoropropene(an inexpensive CF3 structural unit that is harmless to ozone)reacts with enamide to synthesize 4-trifluoromethylated 1,3-butadienes with good yield,high regioselectivity and chemical selectivity,and strong tolerance of substrate functional groups such as alkynes,aldehyde,and ester groups.

关键词： 1,3-Butadienes Trifluoromethylated Heck reaction Palladium Synthetic method

S-wave resonance contributions to B(s)^0→ηc(2S)π^+π^-in the perturbative QCD factorization approach

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Chinese Physics C 2017年第8期41卷 47-52页

作者： Ai-Jun Ma Ya Li wen-fei wang Zhen-Jun Xiao Department of Physics and Institute of Theoretical Physics Nanjing Normal UniversityNanjing 210023China Institute of Theoretical Physics Shanxi UniversityTaiyuanShanxi 030006China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal UniversityNanjing 210023China

By employing the perturbative QCD（PQCD） factorization approach, we study the quasi-two-body B（s）^0→ηc（2S）π^＋π^- decays, where the pion pair comes from the S-wave resonance f0（X）. The Breit-Wigner formula for the f0（500） and f0（1500） resonances and the Flatt′e model for the f0（980） resonance are adopted to parameterize the time-like scalar form factors in the two-pion distribution amplitudes. As a comparison, Bugg＇s model is also used for the wide f0（500） in this work. For decay rates, we found the following PQCD predictions：（a）-B（Bs^0 →ηc（2S）f0（X）[π^＋π^-]s）= 2.67-1.08^＋1.78 ×10^-5 when the contributions from f0（980） and f0（1500） are all taken into account;（b）B（B0→η-c（2S）f0（500）[π^＋π^-]s） = 1.40（-0.56）（＋0.92） ×10^-6 in the Breit-Wigner model and 1.53（-0.61）^（＋0.97） ×10^-6 in Bugg＇s model.

关键词： PQCD factorization approach two-pion distribution amplitudes quasi-two-body decay

Interleukin-22 receptor 1 is expressed in multinucleated giant cells:A study on intestinal tuberculosis and Crohn’s disease

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World Journal of Gastroenterology 2019年第20期25卷 2473-2488页

作者： Zi-Qi Yu wen-fei wang You-Chao Dai Xin-Chun Chen Jian-Yong Chen Department of Gastroenterology and Hepatology Jiangxi Provincial People’s HospitalNanchang 330006Jiangxi ProvinceChina Jiangxi Medical College Nanchang UniversityNanchang 330006Jiangxi ProvinceChina Department of Microbiology and Immunology Shenzhen University Health Science CenterShenzhen 518000Guangdong ProvinceChina Department of Pharmaceutical/Medicinal Chemistry Institute of PharmacyFriedrich Schiller UniversityJena 07743Germany

BACKGROUND It is challenging to distinguish intestinal tuberculosis from Crohn’s disease due to dynamic changes in epidemiology and similar clinical characteristics. Recent studies have shown that polymorphisms in genes involved in the interleukin (IL)- 23/IL-17 axis may affect intestinal mucosal immunity by affecting the differentiation of Th17 cells. AIM To investigate the specific single-nucleotide polymorphisms (SNPs) in genes involved in the IL-23/IL-17 axis and possible pathways that affect susceptibility to intestinal tuberculosis and Crohn's disease. METHODS We analysed 133 patients with intestinal tuberculosis, 128 with Crohn’s disease, and 500 normal controls. DNA was extracted from paraffin-embedded specimens or whole blood. Four SNPs in the IL23/Th17 axis (IL22 rs2227473, IL1β rs1143627, TGFβ rs4803455, and IL17 rs8193036) were genotyped with TaqMan assays. The transcriptional activity levels of different genotypes of rs2227473 were detected by dual luciferase reporter gene assay. The expression of IL-22R1 in different intestinal diseases was detected by immunohistochemistry. RESULTS The A allele frequency of rs2227473 (P = 0.030, odds ratio = 0.60, 95% confidence interval: 0.37-0.95) showed an abnormal distribution between intestinal tuberculosis and healthy controls. The presence of the A allele was associated with a higher IL-22 transcriptional activity (P < 0.05). In addition, IL-22R1 was expressed in intestinal lymphoid tissues, especially under conditions of intestinal tuberculosis, and highly expressed in macrophage-derived Langhans giant cells. The results of immunohistochemistry showed that the expression of IL-22R1 in patients with Crohn's disease and intestinal tuberculosis was significantly higher than that in patients with intestinal polyps and colon cancer (P < 0.01). CONCLUSION High IL-22 expression seems to be a protective factor for intestinal tuberculosis. IL-22R1 is expressed in Langhans giant cells, suggesting that the IL-22/IL-22R1 s

关键词： Crohn's disease Intestinal tuberculosis Single-nucleotide polymorphism Interleukin-22 Interleukin-22 receptor 1 Multinucleated giant cells

Map building for dynamic environments using grid vectors

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第7期12卷 574-588页

作者： wen-fei wang,Rong XIONG ,Jian CHU (State Key Laboratory of Industrial Control Technology,Institute of Cyber-Systems and Control,Zhejiang University,Hangzhou 310027,China) State Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and Control Zhejiang University

This paper addresses the problem of creating a geometric map with a mobile robot in a dynamic indoor *** form an accurate model of the environment,we present a novel map representation called the 'grid vector',which combines each vector that represents a directed line segment with a slender occupancy grid map.A modified expectation maximization (EM) based approach is proposed to evaluate the dynamic objects and simultaneously estimate the robot path and the map of the *** probability of each grid vector is evaluated in the expectation step and then used to distinguish the vector into static and dynamic *** robot path and map are estimated in the maximization step with a graph-based simultaneous localization and mapping (SLAM) *** representation we introduce provides advantages on making the SLAM method strictly statistic,reducing memory cost,identifying the dynamic objects,and improving the accuracy of the data *** SLAM algorithm we present is efficient in computation and *** on three different kinds of data sets show that our representation and algorithm can generate an accurate static map in a dynamic indoor environment.

关键词： Grid vector Line Segments Dynamic Simultaneous localization and mapping (SLAM) Expectation maximization (EM)

Krüppel-like factor 8 overexpression is correlated with angiogenesis and poor prognosis in gastric cancer

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World Journal of Gastroenterology 2013年第27期19卷 4309-4315页

作者： wen-fei wang Juan Li Lu-Tao Du Li-Li wang Yong-Mei Yang Yi-Min Liu Hui Liu Xin Zhang Zhao-Gang Dong Gui-Xi Zheng ChuanXin wang School of Biosciences University of NottinghamSutton Bonington Campus Department of Clinical Laboratory Qilu HospitalShandong University

AIM:To investigate Krüppel-like factor 8 (KLF8) expression in gastric cancer and its relationship with angiogenesis and prognosis of gastric cancer. METHODS:One hundred and fifty-four patients with gastric cancer who underwent successful curative resection were retrospectively enrolled in the study. Fifty tumor-adjacent healthy gastric tissues (≥ 5 cm from the tumor margin) obtained during the original resection were randomly selected for comparative analysis. In situ expression of KLF8 and CD34 proteins were examined by immunohistochemistry. The intratumoral microvessel density (MVD) was determined by manually counting the immunostained CD34-positive endothelial cells in three consecutive high-magnification fields (× 200). The relationship between differential KLF8 expression and MVD was assessed using Spearman's correlation coefficient test. χ2 test was performed to evaluate the effects of differential KLF8 expression on clinicopathologic factors. Kaplan-Meier and multivariate Cox survival analyses were used to assess the prognostic value of differential KLF8 expression in gastric cancer. RESULTS:Significantly higher levels of KLF8 protein were detected in gastric cancer tissues than in the adjacent non-cancerous tissues (54.5% vs 34.0%, P < 0.05). KLF8 expression was associated with tumor size (P < 0.001), local invasion (P = 0.005), regional lymph node metastasis (P = 0.029), distant metastasis (P = 0.023), and tumor node metastasis (TNM) stage (P = 0.002), as well as the MVD (r = 0.392, P < 0.001). Patients with KLF8 positive expression had poorer overall survival (P < 0.001) and cancer-specific survival (P < 0.001) than those with negative expression. Multivariate analysis demonstrated that KLF8 expression independently affected both overall and cancer-specific survival of gastric cancer patients (P = 0.035 and 0.042, respectively). CONCLUSION:KLF8 is closely associated with gastric tumor progression, angiogenesis and poor prognosis, suggesting it may represen

关键词： Gastric cancer Krüppel-like factor 8 Angiogenesis Prognosis

Realtime Gait Kinematics Classification Using LDA and SVM

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Realtime Gait Kinematics Classification Using LDA and SVM