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幂律流体管内充分发展的对流换热分析

石油大学学报（自然科学版） 2004年第2期28卷 71-74页

作者：黄善波李兆敏石油大学储运与建筑工程学院山东东营257061 石油大学石油工程学院山东东营257061

将非牛顿流体的动量方程、能量方程和幂律流体的本构方程相结合 ,建立了幂律流体管内流动和换热充分发展时的对流换热控制方程组 ,并在恒热流和恒壁温边界条件下分别对方程组进行了求解 ,得到了两种不同边界条件下的温度分布和无量纲对... 详细信息

将非牛顿流体的动量方程、能量方程和幂律流体的本构方程相结合 ,建立了幂律流体管内流动和换热充分发展时的对流换热控制方程组 ,并在恒热流和恒壁温边界条件下分别对方程组进行了求解 ,得到了两种不同边界条件下的温度分布和无量纲对流换热系数 (Nu数 )的表达式。结果表明 ,幂律流体的流变指数对流体流动的影响要大于对换热的影响 ;在恒热流边界条件下 ,幂律流体的温度在管内沿轴向呈线性分布 ;而在恒壁温条件下 ,其截面平均温度沿轴向呈指数规律变化。幂律流体的无量纲对流换热系数与幂律流体的流变指数有关 ,并且在两种边界条件下。

关键词：幂律流体换热系数流变指数温度分布边界条件能量方程非牛顿流体

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基于LMI的发电机多目标励磁控制器设计

天津大学学报（自然科学与工程技术版） 2002年第6期35卷 752-756页

作者：车延博王成山赵健科天津大学电气自动化与能源工程学院天津300072

借鉴有极点配置约束混合H2/H∞问题的解法,从多目标控制的角度设计发电机励磁控制器,并用线性矩阵不等式(LMl)技术实现.这种多目标的状态反馈控制,可以使机组在故障前后状态分别达到其各自的性能指标,并且控制代价合理.具体算例说明了... 详细信息

借鉴有极点配置约束混合H2/H∞问题的解法,从多目标控制的角度设计发电机励磁控制器,并用线性矩阵不等式(LMl)技术实现.这种多目标的状态反馈控制,可以使机组在故障前后状态分别达到其各自的性能指标,并且控制代价合理.具体算例说明了设计方法的可行性.

关键词： LMI 发电机多目标励磁控制器线性矩阵不等式设计方法设计指标

Prediction and stratification for the surgical adverse events after minimally invasive esophagectomy:A two-center retrospective study

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World Journal of Gastroenterology 2025年第3期31卷 50-61页

作者： Qi-Hong Zhong Jiang-shan Huang Fei-Long Guo Jing-Yu Wu Mao-Xiu Yuan Jia-Fu Zhu Wen-Wei Lin Sui Chen Zhen-Yang Zhang Jiang-bo Lin Department of Thoracic Surgery Fujian Medical University Union HospitalFuzhou 350001Fujian ProvinceChina The Graduate School Fujian Medical UniversityFuzhou 350001Fujian ProvinceChina Department of Thoracic Surgery Affiliated Hospital of Jinggangshan UniversityJi’an 343000Jiangxi ProvinceChina

BACKGROUND Minimally invasive esophagectomy(MIE)is a widely accepted treatment for esophageal cancer,yet it is associated with a significant risk of surgical adverse events(SAEs),which can compromise patient recovery and long-term *** preoperative identification of high-risk patients is critical for improving *** To establish and validate a risk prediction and stratification model for the risk of SAEs in patients with *** This retrospective study included 747 patients who underwent MIE at two centers from January 2019 to February *** were separated into a train set(n=549)and a validation set(n=198).After screening by least absolute shrinkage and selection operator regression,multivariate logistic regression analyzed clinical and intraoperative variables to identify independent risk factors for SAEs.A risk stratification model was constructed and validated to predict the probability of *** SAEs occurred in 10.2%of patients in train set and 13.6%in the validation *** with SAE had significantly higher complication rate and a longer hospital stay after *** key independent risk factors identified included chronic obstructive pulmonary disease,a history of alcohol consumption,low forced expiratory volume in the first second,and low albumin *** stratification model has excellent prediction accuracy,with an area under the curve of 0.889 for the training set and an area under the curve of 0.793 for the validation *** The developed risk stratification model effectively predicts the risk of SAEs in patients undergoing MIE,facilitating targeted preoperative interventions and improving perioperative management.

关键词： Surgical adverse events Minimally invasive esophagectomy Esophageal cancer Stratification model Perioperative management

Loss-of-function mutations of microRNA-142-3p promote ASH1L expression to induce immune evasion and hepatocellular carcinoma progression

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World Journal of Gastroenterology 2025年第1期31卷 126-145页

作者： Xing-Hui Yu Yan Xie Jian Yu Kun-Ning Zhang Zhou-bo Guo Di Wang zhao-Xian Li Wei-Qi Zhang Yu-Ying Tan Li Zhang Wen-Tao Jiang School of Medicine Nankai UniversityTianjin 300192China Tianjin Key Laboratory of Molecular Diagnosis and Treatment of Liver Cancer Tianjin First Center HospitalTianjin 300192China Department of Liver Transplantation Tianjin First Center HospitalTianjin 300192China First Central Clinical School Tianjin Medical UniversityTianjin 300192China

BACKGROUND Hepatocellular carcinoma(HCC)has been a pervasive malignancy throughout the world with elevated *** therapeutic targets are beneficial to treat and predict the ***,the exact molecular mechanisms leading to the progression of HCC are still *** has shown that the microRNA-142-3p level decreases in HCC,whereas bioinformatics analysis of the cancer genome atlas database shows the ASH1L expression increased among liver tumor *** this paper,we will explore the effects and mechanisms of microRNA-142-3p and ASH1L affect the prognosis of HCC patients and HCC cell bioactivity,and the association between *** To investigate the effects and mechanisms of microRNA-142-3p and ASH1L on the HCC cell bioactivity and prognosis of HCC *** In this study,we grouped HCC patients according to their immunohistochemistry results of ASH1L with pathological tissues,and retrospectively analyzed the prognosis of HCC ***,explored the roles and mechanisms of microRNA-142-3p and ASH1L by cellular and animal experiments,which involved the following experimental methods:Immunohistochemical staining,western blot,quantitative real-time-polymerase chain reaction,flow cytometric analysis,tumor xenografts in nude mice,*** statistical methods involved in this study contained t-test,one-way analysis of variance,theχ^(2)test,the Kaplan-Meier approach and the log-rank *** In this study,we found that HCC patients with high expression of ASH1L possess a more recurrence rate as well as a decreased overall survival ***1L promotes the tumorigenicity of HCC and microRNA-142-3p exhibits reduced expression in HCC tissues and interacts with ASH1L through targeting the ASH1L 3′untranslated ***,microRNA-142-3p promotes apoptosis and inhibits proliferation,invasion,and migration of HCC cell lines in vitro via *** the exploration mechanism,we found ASH1L may promote an immunosuppressive mi

关键词： Hepatocellular carcinoma MicroRNA-142-3p ASH1L Immune evasion Tumor immune microenvironment Apoptosis

Prevalence of Helicobacter pylori infection in Chinese military personnel:A cross-sectional,multicenter-based study

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World Journal of Gastroenterology 2025年第3期31卷 42-49页

作者： Han-Chen Min Chun-Yan Zhang Fang-Yu Wang Xiao-Hui Yu shan-Hong Tang Hong-Wu Zhu Ya-Gang zhao Ji-Luo Liu Jian Wang Jing-Han Guo Xiao-Mei Zhang Yun-Sheng Yang Chinese People’s Liberation Army Medical School Chinese People’s Liberation Army General HospitalBeijing 100853China Department of Gastroenterology and Hepatology The First Medical CenterChinese People’s Liberation Army General HospitalBeijing 100853China Sixth Healthcare Department The Second Medical CenterChinese People’s Liberation Army General HospitalBeijing 100853China Department of Gastroenterology The 940th Hospital of Joint Logistic Support Force of Chinese People’s Liberation ArmyLanzhou 730050Gansu ProvinceChina Department of Gastroenterology General Hospital of Western Theater CommandChengdu 610011Sichuan ProvinceChina Department of Gastroenterology General Hospital of Southern Theater CommandGuangzhou 510010Guangdong ProvinceChina Department of Epidemiology Naval Medical UniversityShanghai 200433China School of Medicine Nankai UniversityTianjin 300071China National Clinical Research Center for Geriatric Diseases Chinese People’s Liberation Army General HospitalBeijing 100853China

BACKGROUND Helicobacter pylori(***)infection is a prevalent disease encountered in military internal medicine and recognized as the main cause of dyspepsia,gastritis,and peptic ulcer,which are common diseases in military *** guidelines in China state all patients with evidence of active infection with *** are offered ***,the prevalence of *** infection and its regional distribution in the military population remain unclear,which hinders effective prevention and treatment *** the prevalence of *** infection in the military population will aid in the development of customized strategies to better manage this infectious *** To investigate the prevalence of *** infection in the Chinese military population in different geographic *** This multicenter,retrospective study included 22421 individuals from five tertiary hospitals located in north,east,southwest,and northwest cities of *** infection was identified using the urea breath test,which had been performed between January 2020 and December *** Of the 22421 military service members,7416(33.1%)were urea breath *** highest prevalence of *** was in the 30-39 years age group for military personnel,with an infection rate of 34.9%.The majority of infected subjects were younger than 40-years-old,accounting for 70.4%of the infected *** individuals serviced in Lanzhou and Chengdu showed a higher infection prevalence than those in Beijing,Nanjing,and Guangzhou,with prevalence rates of 44.3%,37.9%,29.0%,31.1%,and 32.3%,*** *** infection remains a common infectious disease among military personnel in China and has a relatively high prevalence rate in northwest China.

关键词： Helicobacter pylori Prevalence Military personnel Urea breath test Multicenter study

Moment Redistribution Effect of the Continuous Glass Fiber Reinforced Polymer-Concrete Composite Slabs Based on Static Loading Experiment

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Structural Durability & Health Monitoring 2025年第1期19卷 105-123页

作者： zhao-Jun Zhang Wen-Wei Wang Jing-Shui Zhen bo-Cheng Li De-Cheng Cai Yang-Yang Du Hui Huang Offshore Oil Engineering Co.Ltd. Tianjin300461China Department of Bridge Engineering School of TransportationSoutheast UniversityNanjing211189China

This study aimed to investigate the moment redistribution in continuous glass fiber reinforced polymer(GFRP)-concrete composite slabs caused by concrete cracking and steel bar yielding in the negative bending moment *** experimental bending moment redistribution test was conducted on continuous GFRP-concrete composite slabs,and a calculation method based on the conjugate beam method was *** composite slabs were formed by combining GFRP profiles with a concrete layer and supported on steel beams to create two-span continuous composite slab *** methods,epoxy resin bonding,and stud connection,were used to connect the composite slabs with the steel *** experimental findings showed that the specimen connected with epoxy resin exhibited two moments redistribution phenomena during the loading process:concrete cracking and steel bar yielding at the internal *** contrast,the composite slab connected with steel beams by studs exhibited only one-moment redistribution phenomenon throughout the loading *** the concrete at the internal support cracked,the bending moment decreased in the internal support section and increased in the midspan *** the steel bars yielded,the bending moment further decreased in the internal support section and increased in the mid-span *** GFRP profiles do not experience cracking,there was no significant decrease in the bending moment of the mid-span *** test specimens experienced compressive failure of concrete at the mid-span *** results showed good agreement between the calculated and experimental values of bending moments in the mid-span section and internal support *** proposed model can effectively predict the moment redistribution behavior of continuous GFRP-concrete composite slabs.

关键词： Moment redistribution GFRP-concrete composite slabs bending moment experimental study analysis model

Wave effect of gravitational waves intersected with a microlens field Ⅱ:An adaptive hierarchical tree algorithm and population study

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 241-254页

作者： Xikai shan Guoliang Li Xuechun Chen Wen zhao Bin Hu Shude Mao Department of Astronomy Tsinghua University Purple Mountain Observatory Chinese Academy of Sciences Institute for Frontier in Astronomy and Astrophysics Beijing Normal University School of Physics and Astronomy Beijing Normal University School of Astronomy and Space Science University of Science and Technology of China CAS Key Laboratory for Researches in Galaxies and Cosmology Department of Astronomy University of Science and Technology of ChinaChinese Academy of Sciences

The gravitational lensing wave effect generated by a microlensing field embedded in a lens galaxy is an inevitable phenomenon in strong lensed gravitational waves （SLGWs）.This effect presents both challenges and opportunities for the detection and application of ***,investigating this wave effect requires computing a complete diffraction integral over each microlens in the *** is extremely time-consuming due to the large number of microlenses （10～3-10～6）.Therefore,simply adding all the microlenses is ***,the complexity of the time delay surface makes the lens plane resolution a crucial factor in controlling numerical *** this paper,we propose a trapezoid approximation-based adaptive hierarchical tree algorithm to meet the challenges of calculation speed and *** find that this algorithm accelerates the calculation by four orders of magnitude compared to the simple adding method and is one order of magnitude faster than the fixed hierarchical tree algorithm proposed for electromagnetic *** importantly,our algorithm ensures controllable numerical errors,increasing confidence in the *** with our previous work （***.66,239511,2023）,this paper addresses all numerical issues,including integral convergence,precision,and computational time1).Finally,we conducted a population study on the microlensing wave effect of SLGWs using this algorithm and found that the microlensing wave effect cannot be ignored,especially for Type II SLGWs （from saddle position of the time delay surface） due to their intrinsic geometric structures and their typical intersection with a denser microlensing ***,more than 33%（11%） of SLGWs have a mismatch larger than 1%（3%） compared to the unlensed ***,we found that the mismatch between signal pairs in a doubly imaged GW is generally larger than 10-3,and 61%（25%） of signal pairs have a mismatch larger than 1%（3%）.Therefo

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Fiber Bending Flexibility Evaluation by Worm-like Chain Model

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Chinese Journal of Polymer Science 2022年第5期40卷 526-531页

作者： Chao Jin Hui Yu Chun-Fang Wu Hai-bo zhao shan-shan Jin Yu-Liang Yang Hong-Dong Zhang Institute for Preservation and Conservation of Chinese Ancient books Fudan UniversityShanghai 200433China Statekey laboratory of Molecular Engineering of polymers Department of Macromolecular ScienceFudan UniversityShanghai 200433China

A new method for characterizing fiber bending flexibility was developed by worm-like chain model proposed by Kratky-Porod,[1]which was first introduced to the pulp and paper field in this *** the three types of pulps,the experimental results were compared with the KP chain model,and the resulting determination coefficients were all above 0.95,which proved that the model was feasible to be applied to these three *** relation between fiber bending rigidity and that of cellulosic chains inside was discussed to deduce the fiber bending *** flexibility of an individual fiber can be approximated as the contribution of that of all the cellulose chains *** this method,the fiber flexibility values were determined to be in the range of 0.6×10^(11)-3.5×10^(11)N^(-1)·m^(-2),which was comparable to that of the conventional methods recorded in the literature.

关键词： Worm-like chain Fiber persistence length Fiber bending flexibility

Clinical characteristics of adult-type annular pancreas:A case report

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World Journal of Clinical Cases 2020年第22期8卷 5722-5728页

作者： Dan Yi Xiao-bo Ding shan-shan Dong Chen Shao Li-Jing zhao Department of Hepatobiliary and Pancreatic Surgery First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Department of Radiology First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Department of Pathology Beijing You’an HospitalBeijing 100069China Department of Rehabilitation School of NursingJilin UniversityChangchun 130021Jilin ProvinceChina

BACKGROUND Annular pancreas(AP)is a rare congenital abnormal rotation of the *** rarely occurs in *** tumors and ampullary tumors are related to AP,so the discovery and treatment of AP are *** SUMMARY This study investigated the clinical manifestations,imaging features,complications,and treatment of six patients diagnosed with AP at the Department of Hepatobiliary and Pancreatic Surgery,First Hospital of Jilin University from January 2010 to June *** were four males and two females,with an average age of 56.00±9.86 years *** this study,abdominal pain and jaundice were the main clinical *** can show the“crocodile jaw sign”or“double bubble sign”.CONCLUSION For patients with duodenal or biliary obstruction,physicians should give priority to AP when imaging examinations suggest that the duodenum is wrapped with tissue similar to the density of the *** patients should actively undergo surgical treatment.

关键词： Annular pancreas Pancreas/abnormalities Congenital abnormalities Biliary obstruction Duodenal obstruction Case report