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Improvement of P-wave dispersion is associated with a lower incidence of atrial fibrillation after cardiac resynchronization therapy

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Chinese Medical Journal 2012年第6期125卷 990-994页

作者： DING Li-gang HUA wei CHU jian-min QIAO Qing chen Ke-ping wang Fang-zheng zhang Shu Center of Arrhythmia Diagnosis and Treatment Fuwai Hospital and Cardiovascular InstitutePeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100037China

Background P-wave dispersion （PWD） is a useful predictor of paroxysmal atrial fibrillation （AF）. The effect of cardiac resynchronization therapy （CRT） on PWD and the prognostic implications of the improvement in PWD remain undefined. The aim of the study was to explore the clinical significance of the improvement of PWD after CRT. Methods Electrocardiographic studies were performed before and three months after CRT in 81 patients （57 men and 24 women; age （60.5±11.2） years） with standard CRT indication but no history of AF. A significant improvement of PWD （PWD responder） was defined as a relative decrease 〉20% from baseline PWD. The primary endpoints were new-onset AF detected by electrocardiogram （ECG） or CRT. Results After （30.6±7.5） months of follow-up, PWD responders （n=43） had a significantly lower incidence of AF than did PWD nonresponders, 12% vs. 29% （P 〈0.001）. In Cox proportional hazard analysis, PWD responders was the only predictor of lower risk of new-onset AF （HR 0.33, 95% confidence interval 0.12-0.96, P=0.033）. Conclusion Improvement of P-wave dispersion after CRT was associated with a lower incidence of AF, which may be related to the significant improvement in left ventricular systolic function and the reverse modeling of the left atrium.

关键词： atrial fibrillation cardiac resynchronization therapy heart failure P-wave dispersion

Metallographic sample prepared by ion beam etching

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中国有色金属学会会刊：英文版 2004年第z1期14卷 282-285页

作者： xu Xiang-yang zhang Kun HAN jian-min chen Guang-nan Institute of Materials Science & Engineering Beijing Jiaotong University Beijing 100044 China Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Institute of Materials Science & Engineering Beijing Jiaotong University Beijing 100044 China

Ion beam etching technique was used to reveal the metallograhpic microstructure and interface morphology of electroplating chromium coating, in particular, whose substrate surface layer was treated in advance by laser quenching. Chemical etchings were also conducted for comparison. The reveal microstructures were observed and analyzed by scanning electron microscopy. The results show that ion beam etching can reveal well the whole microstructures of composite coating-substrate materials.

关键词： ion beam etching metallography microstructure electroplating chromium

Effects of operating parameters on the flow field in slab continuous casting molds with narrow widths

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International Journal of minerals,Metallurgy and Materials 2021年第2期28卷 238-248页

作者： Tao zhang jian Yang gang-jun xu Hong-jun Liu Jun-jun Zhou wei Qin State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China Hunan Valin Lianyuan Iron&Steel Co. Ltd.Loudi 417000China

Computational simulations and high-temperature measurements of velocities near the surface of a mold were carried out by using the rod deflection method to study the effects of various operating parameters on the flow field in slab continuous casting(CC)molds with narrow widths for the production of automobile exposed *** agreement between the calculated results and measured subsurface velocities of liquid steel was obtained under different operating parameters of the CC *** simulation results reveal that the flow field in the horizontal plane located 50 mm from the meniscus can be used as the characteristic flow field to optimize the flow field of molten steel in the *** in casting speed can increase the subsurface velocity of molten steel and shift the position of the vortex core downward in the downward circulation *** flow field of liquid steel in a 1040 mm-wide slab CC mold can be improved by an Ar gas flow rate of 7 L·min^−1 and casting speed of 1.7 m·min^−*** the present experimental conditions,the double-roll flow pattern is generally stable at a submerged entry nozzle immersion depth of 170 mm.

关键词： flow field rod deflection method continuous casting narrow width numerical simulation operating parameters

Effects of fibers on the mechanical properties of UHPC:A review

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第3期9卷 363-387页

作者： jian Yang Baochun chen Jiazhan Su gang xu Dong zhang Jialiang Zhou Hubei Key Laboratory of Disaster Prevention and Mitigation Yichang 443002China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China School of Civil Engineering Fujian University of TechnologyFuzhou 350116China College of Civil Engineering Fuzhou UniversityFuzhou 350116China National Center for Joint International Research of Bridges Technology Innovation and Risk Mitigation Fuzhou UniversityFuzhou 350116China

Ultra-high performance concrete(UHPC) developed rapidly in research and commercial use during the recent decade. Significant progress has been achieved in its material science and technology, including why and how to add discontinuous fiber reinforcement in *** paper reviews the researches on understanding the effects of various fibers on the mechanical properties of UHPC, focus on the straight steel fibers but involving also deformed steel fibers, non-steel fibers as well as hybrid fibers. It also discusses the research methodology, prediction of mechanical properties by fiber factors, and the classification of UHPC mechanical properties related to this topic. It shows that(1) the experimental research is the main methodology for investigating the effect of the fibers on the mechanical properties of UHPC;the tensile performance of UHPC should be studied by uniaxial tensile tests and its representative indicators should include tensile strength, initial cracking strength, and peak tensile strain;(2) fiber plays an essential role in the reinforcement of the tensile strength, compressive strength, modulus of elasticity, and other material properties of UHPC, but in weakening the flowability of fresh UHPC. The positive and negative effects of fibers on the mechanical properties of UHPC should be considered,and the technology should be developed to maintain the flowability when high volume fraction of fibers is added in the UHPC;(3) the parameters of steel fibers affecting the mechanical properties of UHPC include volume fraction, size, shape, orientation and distribution, average bonding strength and minimum tensile strength, etc., which are mainly studied independently in the existing research. The studies on the combined effect of these parameters are limited but worthy of further investigation;(4) hybrid fibers could efficiently produce reinforcement effects for UHPC. It has great practical and research significance to conduct in-depth studies though the theoret

关键词： Ultra-high performance concrete(UHPC) Fiber reinforcement Effect factor Hybrid fiber Quantitative analysis Mechanical properties

Identification of salivary proteins in the whitefly Bemisia tabaci by transcriptomic and LC-MS/MS analyses

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Insect Science 2021年第5期28卷 1369-1381页

作者： Hai-jian Huang Zhuang-Xin Ye gang Lu Chuan-Xi zhang jian-Ping chen Jun-min Li State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Key Laboratory of Biotechnology in Plant Protection of MOA of China and Zhejiang ProvinceInstitute of Plant VirologyNingbo UniversityNingboZhejiang315211.China

The whitefly Bemisia tabaci is a notorious agricultural pest of many crops *** it is thought that *** secretes saliva into the host plant to counter plant defenses,knowledge on the whitefly salivary proteome is ***,we characterized the gene/protein repertoires of *** salivary glands and secreted saliva by transcriptomic and liquid chromatography tandem mass spectroscopy analyses.A total of 698 salivary gland-enriched unigenes and 171 salivary proteins were *** analysis between the *** salivary proteins and those of different arthropod species revealed numerous similarities in proteins associated with binding,hydrolysis,and oxidation-reduction,which demonstrates a degree of conservation across herbivorous *** were 74 proteins only identified in *** saliva,of which 34 were *** addition,13 salivary proteins,of which I1 were ***-specific,were differentially regulated when *** fed on different *** results provide a good resource for future functional studies of whitefly salivary effectors,and might be useful in pest management.

关键词： Bemisia tabaci proteome salivary protein species-specific transcriptome

Predictive significance of serum inhibin B on testicular haploid gamete retrieval outcomes in nonobstructive azoospermic men

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Asian Journal of Andrology 2019年第2期21卷 137-142页

作者： Zhi-Guo Zhu Zhi-gang Zhao Qing-Yang Pang Tong chen jian-min zhang Tai-jian zhang Chao xu Hao-Bo zhang Wen Liu xu-Jun xuan Department of Urology and Andrology Minimally Invasive Surgery CenterThe First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510230China Guangzhou Institute of Urology Guangzhou 510230China Guangdong Key Laboratory of Urology Guangzhou 510230China Center for Reproductive Medicine Shandong UniversityJinan 250001China National Research Center for Assisted Reproductive Technology and Reproductive Genetics Jinan 250001China The Key Laboratory for Reproductive Endocrinology of ministry of Education Jinan 250001China Shandong Xiehe University Jinan 250109China

The purpose of this study was to determine the diagnostic accuracy of serum inhibin B(INHB)as a predictor of the retrieval outcome of testicular haploid gametes(spermatids and testicular spermatozoa)in nonobstructive azoospermic *** hormone levels,testicular volume,and histological evaluation were performed in 403 Chin ese non obstructive azoospermic *** haploid gamete was successfully retrieved in 213 of 403 patients(52.85%).The haploid gamete group always had higher INHB levels than the non-haploid gamete *** to the receiver operating characteristic(ROC)curve analysis,INHB was a good predictor of testicular haploid gamete retrieval outcome in all patients(sensitivity:77.93%and specificity:91.58%)and patients with normal follicle-stimulating hormone(FSH;sensitivity:88.52%and specificity:70.83%).The area under the ROC curve(AUC)of INHB was similar to that of FSH in all patients or patients with normal *** patients with elevated FSH,INHB was superior to FSH in predicting the presence of haploid gamete(AUC:0.73 vs 0.55,P<0.05),with a sensitivity of 60.00%and a specificity of 80.28%.It con eluded that serum INHB as an effective marker for spermatoge nesis was a sign ificant predictor of testicular haploid gamete retrieval outcomes in nonobstructive azoospermic ***,INHB is superior to FSH in predicting the presenee of haploid gamete in the patients with elevated FSH.

关键词： azoospermia biomarker follicle-stimulating hormone inhibin B testicular sperm extraction

Genotyping the Heading Date of Male-Sterile Rice line II-32A

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Journal of Integrative Plant Biology 2006年第4期48卷 440-446页

作者： Jun-Feng xu ling jiang Xiang-Jin wei wei-Wen zhang Shi-Jia Liu Liang-ming chen Chun-ming wang lin-Guang Luo jian-min Wan State Key Laboratory of Crop Genetics and Germplasm Enhancement Research Center of Jiangsu Plant Gene Engineering Nanjing Agricultural University Nanjing 210095 China jiangxi Academy of Agricultural Science Nanchang 330200 China

II-32A, an elite male-sterile line of rice （Oryza sativa L.）, has been widely used for the production of hybrid rice seed In China. Heading date In most combinations using II-32A shows transgressive Inheritance or similarity to the latter parent, but the genotype of II-32A with respect to major genes for heading time Is unknown. This limits the further exploitation of this sterile line In breeding and hybrid seed production. Using a number of major gene heading date Isogenlc lines and heading date QTL near-lsogenic lines, we genetically analyzed II-32B under both long- and short-day conditions. We show that II-32B carries two photoperlod-sensltlve genes, E1 and E3, a recessive late-heading gene, ef-l, and a photoperlod-sensltlve allele, Se-1^u. In addition we Identified In II- 32B a recessive Inhibitor for E1 or Se-1^n and other modified photoperlod-sensltlve genes. The heading-date constitution of II-32A was determined to be E1e2E3Se-1^uef-li-Se-1.

关键词： heading date near-isogenic line photoperiod-sensitive gene recessive late-heading gene rice.

电针“四白”和“颧髎”激活小鼠躯体感觉运动皮层的兴奋性神经元

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针刺研究 2024年第5期49卷 480-486页

作者：张芷晴申晨薇陈明权杜梓霏陈秋怡姬昌张文捷许能贵刘健华广州中医药大学广州510006 广州中医药大学第二临床医学院广州510120 广州中医药大学针灸康复临床医学院华南针灸研究中心广州510006 广州中医药大学基础医学院广州510006 暨南大学第一附属医院广州510630

目的:探讨电针“四白”和“颧髎”对小鼠躯体感觉皮层和初级运动皮层神经元的激活状态及其分型的影响。方法:雄性C57BL/6J小鼠随机分为空白组和电针组,每组6只。电针组电针“四白”和“颧髎”,干预30 min。采用免疫荧光染色法观察躯体... 详细信息

目的:探讨电针“四白”和“颧髎”对小鼠躯体感觉皮层和初级运动皮层神经元的激活状态及其分型的影响。方法:雄性C57BL/6J小鼠随机分为空白组和电针组,每组6只。电针组电针“四白”和“颧髎”,干预30 min。采用免疫荧光染色法观察躯体感觉皮层和初级运动皮层即刻早期基因c-Fos的阳性细胞密度,以及c-Fos阳性细胞和钙/钙调蛋白依赖性蛋白激酶Ⅱ(CaMKⅡ)/γ-氨基丁酸(GABA)共表达细胞的百分比,分析电针后躯体感觉皮层和初级运动皮层c-Fos神经元的类型。另取10只小鼠,采用光纤钙成像技术分别观察电针前后躯体感觉皮层和初级运动皮层兴奋性神经元钙活动的变化。结果:在躯体感觉皮层和初级运动皮层中,电针组的c-Fos阳性细胞密度显著高于空白组(P<0.05)。在躯体感觉皮层和初级运动皮层中,电针组c-Fos和CaMKⅡ共表达细胞百分比显著高于空白组(P<0.01)。光纤记录钙成像结果显示,与电针前相比,电针期间躯体感觉皮层和初级运动皮层兴奋性神经元的自发钙活动显著上升(P<0.01);电针后,其自发钙活动较电针期间显著降低(P<0.05)。结论:在生理状态下,针刺“四白”和“颧髎”能够有效激活躯体感觉皮层和初级运动皮层的兴奋性神经元。

关键词：电针躯体感觉皮层初级运动皮层四白颧髎

Negative Association of Domestic Activity and Active Commuting with Metabolic Syndrome in a Chinese Population Aged 35-64 Years

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Biomedical and Environmental Sciences 2015年第7期28卷 486-494页

作者： chen Xiao rong zhang jian DING gang Qiang DONG Zhong zhang Xin wei LI jian Hong chen Bo YAN Liu Xia MI Sheng Quan ZHAO Wen Hua National Center for Chronic and Noncommunicable Disease Control and Prevention Chinese CDC National Institute for Nutrition and Health Chinese CDC Beijing Center for Diseases Prevention and Control Zhejiang Center for Diseases Prevention and Control College of Applied Arts and Science of Beijing Union University

Objective To understand the associations of physical activity domains with metabolic syndrome among a middle-aged Chinese population. Methods In all, 3326 professional adults aged 35-64 years from Beijing and Zhejiang province were recruited with a cluster random sampling method. The Global Physical Activity Questionnaire was modified, and the recommended Asia-Pacific cut-offs of waist circumstance were introduced into the criteria for metabolic syndrome from the Adult Treatment Panel III. A binary logistic regression model was applied to examine the association of all physical activity domains with the risk of the syndrome. Results Participants who engaged in domestic activity for 〉1176 MET-min/week had a 41.6% less chance of having metabolic syndrome [odds ratio （OR）, 0.584; 95% confidence interval （CI）, 0.480-0.710] than those without this activity. In adjusted models, adults who actively commuted for 〉33 MET-rain/week but 〈52g MET-min/week had a 25% less chance of having the syndrome （OR, 0.750; 95% CI, 0.582-0.966） than those who did not. No interaction was detected between the two domains of activity and the syndrome. Conclusion This study highlighted the independently negative association of traffic and house activity with the prevalence of the syndrome in this sample with a generally low level of moderate activity.

关键词： Physical activity Activities of daily living Metabolic syndrome X