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Risk factors of Low Back Pain among the Chinese Occupational Population:A Case-control Study

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Biomedical and Environmental Sciences 2012年第4期25卷 421-429页

作者： LI Jing Yun WANG Sheng HE Li Hua WU shan shan YANG Lei YU shan fa LI Li Ping WANG Jian Xin HUANG Yan Di Department of Occupational and Environmental Health School of Public Health Peking University Beo'ing 100191 China School of Public Health Tongji Medical Collage Huazhong University of Science and Technology Wuhan 430030 Hubei China Administration Department Henan Provincial Institute of Occupational Health Zhengzhou 450052 Henan China Injury Prevention Research Center Medical College of Shantou University Shantou 515041 Guangdong China Beijing Centers for Disease Control and Prevention Beo'ing 100020 China Beijing Municipal Institute of Labor Protection Beijing 100054 China

Objective To explore the risk factors of low back pain among the Chinese occupational population in several major industries. Methods A total of 7200 subjects （3600 cases and 3600 controls） were randomly sampled from a cross-sectional study, and they were investigated for individual and occupational factors of low back pain. The potential risk factors were first selected by using chi-square tests. Secondly, collinearity diagnosis proceeded by using the Kendall＇s rank correlation. Finally, binary logistic regression model was used for multi-factor analysis. Results Collinearity diagnosis showed that there was a severe collinearity problem among the potential risk factors of low back pain. Logistic regression model included 20 variables with statistical significance. Bending neck forward or holding neck in a forward posturefor long periods （0R=1.408） was the most important risk factor inducing low back pain in this study, followed by bending heavily with the trunk （0R=1.402）, carrying out identical work almost for the whole day （0R=1.340）. Additionally, suHicient normal break was a protective factor of low back pain. Conclusion Low back pain among the Chinese occupational population was associated with body height, occupation, work organization, physical work, working posture, and others. All these risk factors could be regarded as the indicators of low back pain, and some relevant preventive measures should be taken to reduce low back pain risk.

关键词： Case-control studies Low back pain Occupational health Risk factors

Enantioselective extraction of terbutaline enantiomers by lipophilic tartaric acid

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Journal of Central South University of Technology 2003年第1期10卷 44-48页

作者： tang Ke-wen(唐课文) ZHOU Chun-shan(周春山) College of Chemistry and Chemical Engineering Central South University Changsha 410083 China Department of Chemistry and Chemical Engineering Yueyang Normal University Yueyang 414000 China College of Chemistry and Chemical Engineering Central South University Changsha 410083 China

Distribution behavior of terbutaline enantiomers was examined in the aqueous and organic solvent of a two-phase system containing L-dibenzoyltartaric acid and lipophilic phase transfer reagent of Na-tetraphenylborate. The influences of pH, organic solvents, concentrations of Na-tetraphenylborate and L-dibenzoyltartaric acid on the partition coefficients and enantioselectivity of terbutaline enantiomers, were investigated. The results show that tetraphenylborate lipophilic anion and terbutaline enantiomers form two lipophilic salt complexes , which facilitates the solubility of the enantiomers in the organic phase. L-dibenzoyltartaric acid forms more stable complexes with enantiomer Ⅱ than with enantiomer I . Enantioselectivity and partition coefficient increase with the addition of the length of alkyl chain of alcohols. pH and concentrations of lipophilic anion and L-dibenzoyltartaric acid influence them obviously and differently.

关键词： L-dibenzoyltartaric acid terbutaline enantiomers chiral extraction

Effects of transjugular intrahepatic portosystemic shunt using the Viatorr stent on hepatic reserve function in patients with cirrhosis

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World Journal of Clinical Cases 2021年第7期9卷 1532-1542页

作者： Xin Yao Hao Zhou shan Huang shan-Hong tang Jian-Ping Qin Department of Gastroenterology General Hospital of Western Theater CommandChengdu 610083Sichuan ProvinceChina Department of Gastroenterology Fengjie County People's HospitalChongqing 404600China Department of Digestive Medicine General Hospital of Western Theater CommandChengdu 610083Sichuan ProvinceChina Department of Digestion General Hospital of Western Theater CommandChengdu 610083Sichuan ProvinceChina

BACKGROUND As transjugular intrahepatic portosystemic shunt(TIPS)creation alters the hemodynamic status of the portal system,whether reduced portal blood supply affects the synthetic reserve function of the liver has been the focus of clinical *** the Viatorr stent entered the Chinese market in 2015,it has not yet been widely used in clinical ***,unlike other countries,the main cause of liver cirrhosis in China is viral ***,use of the Viatorr stent to establish a TIPS channel in patients with liver cirrhosis with differing etiologies is of great clinical *** To investigate factors affecting changes in liver reserve function after TIPS Viatorr stent *** Clinical data from 200 patients with cirrhotic portal hypertension who received TIPS treatment from March 2016 to March 2020 were analyzed *** patients were divided into three groups(A-C),according to their disease etiology,with post-hepatitis,autoimmune,and alcoholic cirrhosis,*** and postoperative liver and renal function and coagulation data,Child-Pugh grade,and model for end-stage liver disease(MELD)scores were *** analyses were performed using the t-test or chi-square *** incidence and of hepatic encephalopathy and patient survival were calculated using Kaplan-Meier *** The surgical success rate was 100%,with mean portal pressure gradient(mmHg)decreasing from 25.5±5.22 to 10.04±2.76(t=45.80;P<0.001).After 24 mo,the cumulative incidence of hepatic encephalopathy in group A was significantly lower than that in group B/C,while the cumulative survival rate was significantly higher in group A than in group B/C(P<0.05 for both).The Child-Pugh score for group A was 6.96±1.21,which was significantly better than those of groups B(7.42±0.99;t=-2.44;P=0.016)and C(7.52±1.12;t=-2.67;P=0.009).Further,the MELD score for group A(9.62±2.19)was significantly better than those for groups B(10.64

关键词： Portal shunt,transjugular intrahepatic Hypertension Viatorr stent Liver reserve function

A local-optimization refinement algorithm in single particle analysis for macromolecular complex with multiple rigid modules

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Protein & Cell 2016年第1期7卷 46-62页

作者： Hong shan Zihao wang fa Zhang Yong Xiong Chang-Cheng Yin Fei Sun Department of Biophysics College of Basic Medical Sciences Peking University Health Science Center Beijing 100191China National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Key Lab of Intelligent Information Processing and Advanced Computing Research Lab Institute of Computing TechnologyChinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China Department of Molecular Biophysics and Biochemistry Yale University New Haven CT 06511 USA Center for Biological Imaging Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

Single particle analysis, which can be regarded as an average of signals from thousands or even millions of particle projections, is an efficient method to study the three-dimensional structures of biological macro- molecules. An intrinsic assumption in single particle analysis is that all the analyzed particles must have identical composition and conformation. Thus specimen heterogeneity in either composition or conformation has raised great challenges for high-resolution analysis. For particles with multiple conformations, inaccurate align- ments and orientation parameters will yield an averaged map with diminished resolution and smeared density. Besides extensive classification approaches, here based on the assumption that the macromolecular complex is made up of multiple rigid modules whose relative orien- tations and positions are in slight fluctuation around equilibriums, we propose a new method called as local optimization refinement to address this conformational heterogeneity for an improved resolution. The key idea is to optimize the orientation and shift parameters of each rigid module and then reconstruct their three-dimen- sional structures individually. Using simulated data of 80S/70S ribosomes with relative fluctuations between the large （60S/50S） and the small （40S/30S） subunits, we tested this algorithm and found that the resolutions of both subunits are significantly improved. Our method provides a proof-of-principle solution for high-resolutionsingle particle analysis of macromolecular complexes with dynamic conformations.

关键词： cryo-electron microscopy single particleanalysis conformational heterogeneity rigid module Iocaoptimization refinement

Clinical efficacy of antiviral therapy in patients with hepatitis Brelated cirrhosis after transjugular intrahepatic portosystemic shunt

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World Journal of Gastroenterology 2021年第30期27卷 5088-5099页

作者： Xin Yao shan Huang Hao Zhou shan-Hong tang Jian-Ping Qin Department of Gastroenterology General Hospital of Western Theater CommandChengdu 610083Sichuan ProvinceChina Department of Gastroenterology Fengjie County People's HospitalChongqing 404600China

BACKGROUND As a country with a high burden of hepatitis B,China has about 86 million cases of hepatitis B virus infection,ranking the first in the ***,there are about 390000 deaths due to hepatitis B-related complications such as liver cirrhosis and liver cancer every ***,how to control portal hypertension,improve liver functional reserve,and reduce the incidence of hepatic failure and liver cancer in such patients is the focus of current clinical *** clinical study in our center suggested that at 24 mo after transjugular intrahepatic portosystemic shunt(TIPS),the liver functional reserve of patients with hepatitis B cirrhosis was better than that of patients with alcoholinduced and immune cirrhosis,which may be related to the effective etiological *** To investigate the clinical efficacy of three first-line antiviral drugs recommended by the guidelines of prevention and treatment for chronic hepatitis B in China(2019)in the treatment of patients with hepatitis B-related cirrhosis who had received a *** The clinical data of 137 patients with hepatitis B-related cirrhosis with portal hypertension after receiving TIPS at our centre between March 2016 and December 2020 were analysed *** to different anti-viral drugs,the patients were divided into entecavir(ETV)(n=70),tenofovir alafenamide fumarate(TAF)(n=32),and tenofovir disoproxil fumarate(TDF)(n=35)*** cumulative incidence of hepatic encephalopathy and hepatocellular carcinoma,survival,and changes in hepatic reserve function and glomerular filtration rate in patients treated with different antiviral drugs within 24 mo after surgery were *** At 24 mo after surgery,the Child-Pugh score in the TAF group(6.97±0.86)was lower than that in the TDF(7.49±0.82;t=-2.52,P=0.014)and ETV groups(7.64±1.17;t=-2.92,P=0.004).The model for end-stage liver disease score in the TAF group at 24 mo after surgery was 9.72±1.5,which was

关键词： Transjugular intrahepatic portosystemic shunt Hypertension Antiviral Hepatitis B-related cirrhosis Liver reserve function

Corrosion Behavior of S450EW Low-alloy Weathering Steel in Cyclically Alternate Corrosion Environments

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Journal of Iron and Steel Research International 2015年第11期22卷 1020-1023页

作者： Jun-shan WANG Pei-yang SHI Cheng-jun LIU Mao-fa JIANG Key Laboratory of Ecological Metallurgy of Multimetallic Mineral Northeastern University Ansteel Group Co. Ltd.

Weathering steel is widely used in various fields due to its excellent mechanical properties and high corrosion resistance. The effect of chromium content on the S450 EW weathering steel in cyclic immersion test was studied. The results indicated that the corrosion resistance of S450 EW weathering steel is closely related to chromium content. The addition of chromium significantly inhibited the weathering steel corrosion. The corrosion rate of experimental steel after 96 h immersion was 1.101 g·m-2·h-1. The rust of S450 EW weathering steel was mainly constituted of Fe OOH and Fe3O4 phase, and the elevation of chromium content promoted the formation of α-Fe OOH. The fine precipitates of the two phases contributed to the formation of dense dust layer of test steel. Furthermore, the increase of chromium is beneficial for the cure of original defects and cracks of the rust layer via the enrichment of chromium. The corrosion potential and the resistance of corrosion process were thus increased, protecting the experimental steel from further corrosion. A S450 EW steel with corrosion resistance more than 1.5 times of Q450NQR1 steel was prepared.

关键词： weathering steel cyclic immersion test rust structure chromium corrosion resistance

Semi-synthesis of disulfide-linked branched tri-ubiquitin mimics

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Science China Chemistry 2018年第4期61卷 412-417页

作者： Yanyan Si Lujun Liang shan tang Yunkun Qi Yong Huang Lei Liu Key Laboratory of Chemical Genomics School of Chemical Biology and BiotechnologyPeking UniversityShenzhen Graduate School Department of Chemistry Tsinghua University

Ubiquitin(Ub) chain isopeptide bond mimics are useful molecules for biochemical and biophysical studies. Herein, we report the semi-synthesis of the disulfide-linked K11/K48-branched tri-Ub(Ub_3^(11/48)(S-S)), the first example of an isopeptide mimic for the branched Ub chains,which have recently emerged as an interesting category of Ub modifications. Our strategy comprised the El-dependent synthesis of the Ub conjugate of aminoethanethiol, followed by disulfide formation with Ub(K11 C, K48 C). The structure of the synthetic isopeptide bond mimics was verified by the crystal structure of Ub_3^(11/48)(S-S). Deubiquitination and pulldown assays indicated that the synthetic Ub_3^(11/48)(S-S) could be hydrolyzed by linkage-specific deubiquitinases(K11-specific Cezanne and K48-specific OTUB1), and recognized by proteasomal ubiquitin receptor S5 a.

关键词： ubiquitin chain isopeptide bond mimics disulfide-directed strategy branched Ub chains crystal structure

Multiple hierarchy risk assessment with hybrid model for safety enhancing of unmanned subscale BWB demonstrator flight test

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Chinese Journal of Aeronautics 2019年第12期32卷 2612-2626页

作者： Yi LU Shuguang ZHANG Zejing ZHANG Xuan ZHANG Peng tang shan FU Department of Automation School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Transportation Science and Engineering Beihang UniversityBeijing 100083China Airworthiness Technologies Research and Management Center China Aviation Polytechnology EstablishmentBeijing 100028China China Electronic Product Reliability and Environmental Testing Research Institute Guangzhou 510610China School of Energy and Power Engineering Beihang UniversityBeijing 100083China

To explore the low-speed characteristics of the Blended-Wing-Body(BWB)configuration for future civil aircraft,a series of unmanned subscale demonstrators have been developed and tested by our research *** this process,specific safety risks deriving from uncertain design features,system unreliability,and insufficient personnel experience caused continuous flight test mishaps and the risk mechanism was not *** and trial-and-error learning driven safety improvements took few effects on mishap prevention,so our focus was turned to look for systematic safety *** paper establishes a systems theory based hybrid model to integrate the physical system reliability analysis techniques with the system dynamics method for illustrating the multiple risk interactions of the demonstrator flight test involving organizational,human resource and technical system *** the prior BB-5 demonstrator as a case,the hybrid model simulation represents its historical risk evolution process,which verifies the model rational*** risk control strategies reduced the mishap rate of a new demonstrator called BB-6 *** paper also shows the extended hybrid model can be applied on safety management of unmanned aerial vehicles from the initial period of vehicle development.

关键词： Blended-wing-body Demonstration flight test Markov analysis Risk assessment Strategy experiment System dynamics Systems theory

High-performance self-powered GaN/PEDOT:PSS hybrid heterojunction UV photodetector for optical communication

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Science China(Technological Sciences) 2024年第2期67卷 608-615页

作者： LI shan LIU Zeng ZHANG MaoLin YANG LiLi GUO YuFeng tang WeiHua College of Integrated Circuit Science and Engineering&National and Local Joint Engineering Laboratory for RF Integration and Micro-Packing Technologies Nanjing University of Posts and TelecommunicationsNanjing 210023China

Self-powered ultraviolet photodetectors(UVPDs)provide great possibility for the next-generation energy conservation optical communication technology;while the high photodetection performance at zero bias is still a tremendous ***,ntype GaN film with Si-doping concentration of~1018cm^(-3)and p-type organic PEDOT:PSS were adopted to construct a planar hybrid heterojunction via the simple spin-coating *** from typical type-Ⅱenergy band alignment and giant photovoltaic effect at GaN/PEDOT:PSS inorganic-organic interface,the fabricated UVPD achieved excellent self-powered photoelectrical properties in dual-band with large R of 0.96 A/W(2.8 A/W),superior D*of 5.7×1012Jones(1.7×10^(13)Jones),prominent EQE of 325%(1371%),high on/off ratio of 9.65×10^(3)(6.15×10^(3))and fast rise/decay time of 60.7/124.5 ms(30.9/26.7 ms)for UVA(UVC)band,as well as outstanding UV/visible rejection ratio and great detection *** as an optical signal receiver,this designed self-powered UVPD decoded a message of“NJUPT”from a simple optical communication *** results open a new avenue for GaN/PEDOT:PSS heterojunction in UV communications and related applications.

关键词： GaN UV photodetector self-powered heterojunction optical communication

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