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Implicit nonlinear FEM for steel sets in tunnels

Science China(Technological Sciences) 2023年第3期66卷 771-783页

作者： kong ci XIAO Ming YUAN QingTeng State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering Ministry of EducationWuhan UniversityWuhan 430072China

Steel sets are widely used in tunnels with unfavorable geological conditions.Such steel sets always have small dimensions and are densely installed on the excavation surface,which is why performing nonlinear analysis on steel sets in actual engineering is a challenging task.Therefore,an implicit nonlinear finite element method(FEM)for steel sets in tunnels was proposed.First,considering the mechanical characteristics of the steel set,a mathematical model of the steel set was proposed,which can accurately reflect the arch effect of the steel set.Then,the stress-strain relationship of the steel set was divided into the linear elastic stage,the first yield platform stage,the nonlinear hardening stage,and the second yield platform stage.In combination with the mixed hardening model,a nonlinear mechanical model of the steel set was established,and its rationality was verified by a thick aluminum ring example.Thirdly,for the convenience of engineering applications,steel sets were implied into rock elements,and their elastoplastic stiffness was superimposed into rock elements to reflect their supporting action.Furthermore,a stress update algorithm for the steel sets in the nonlinear iterative process and a method to simulate their fracture failure were provided.These models were incorporated into a self-developed FEM program to conduct nonlinear analysis for steel sets in tunnels.Finally,the proposed method was applied in a cross-fault hydraulic tunnel.The results proved its rationality,and some conclusions of interest were obtained.This method does not need to establish a complex solid model for steel sets,has no influence on the meshes of rock elements,and can simulate the whole process of steel sets from the linear elastic stage to the nonlinear hardening stage and finally to the fracture failure stage.Thus,it may be a convenient method of simulating steel sets in tunnels.

关键词： steel sets mathematical model nonlinear mechanical model implicit simulation method

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Evaluation of dry eye disease symptomatology and mental health status among patients with different COVID-19 statuses

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 822-830页

作者： Fang Ruan Wen-Jun kong Qian Fan Hong-Wei Dong Wei Zhang Wen-Bin Wei Ying Jie Department of Ophthalmology Beijing You’an HospitalCapital Medical UniversityBeijing Infectious Eye Disease Diagnosis and Treatment CenterBeijing 100069China Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijing Institute of OphthalmologyBeijing Ophthalmology and Visual Sciences Key LabBeijing 100730China Tianjin Eye Hospital Tianjin Key Lab of Ophthalmology and Visual ScienceTianjin Eye InstituteNankai University Affiliated Eye HospitalNankai University Eye InstituteNankai UniversityClinical College of OphthalmologyTianjin Medical UniversityTianjin 300020China

AIM:To evaluate dry eye disease(DED)symptomatology and mental health status in different COVID-19 patients.METHODS:A cross-sectional observational design was used.Totally 123 eligible adults(46.34%of men,age range,18-59y)with COVID-19 included in the study from August to November,2022.Ocular Surface Disease Index(OSDI),Five-item Dry Eye Questionnaire(DEQ-5),Hospital Anxiety and Depression Scale(HADS),and Pittsburgh Sleep Quality Index(PSQI)were used in this study.RESULTS:OSDI scores were 6.82(1.25,15.91)in asymptomatic carriers,7.35(2.50,18.38)in mild cases,and 16.67(4.43,28.04)in recurrent cases,with 30.00%,35.56%,and 57.89%,respectively evaluated as having DED symptoms(χ2=7.049,P=0.029).DEQ-5 score varied from 2.00(0,6.00)in asymptomatic carriers,3.00(0,8.00)in mild cases,and 8.00(5.00,10.00)in recurrent cases,with 27.50%,33.33%,and 55.26%,respectively assessed as having DED symptoms(χ2=8.532,P=0.014).The prevalence of clinical anxiety(50.00%)and depression(47.37%)symptoms were also significantly higher in patients with recurrent infection(χ2=24.541,Pci),1.631-7.979;P=0.033]and DEQ-5 scores(odds ratio,3.353;95%ci,1.038-8.834;P=0.043),whereas having a fixed occupation was a protective factor for OSDI scores(odds ratio,0.088;95%ci,0.022-0.360;P=0.001)and DEQ-5 scores(odds ratio,0.126;95%ci,0.039-0.405;P=0.001).CONCLUSION:Patients with recurrent COVID-19 have more severe symptoms of DED,anxiety,and depression.

关键词： COVID-19 dry eye disease recurrent infection mental health

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区域尺度地埋管地源热泵与能源地下结构开采浅层地热能评价综述

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岩土力学 2024年第5期45卷 1265-1283页

作者：孔纲强常洪林王天赐杨庆河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210098 大连理工大学海岸和近海工程国家重点实验室辽宁大连116024

随着浅层地热能的大规模开发利用,针对地埋管地源热泵和能源地下结构的研究正由单个、单体尺度逐渐转向区域尺度。相较于地埋管地源热泵,能源地下结构占地面积小、成本低,在大规模城市建设及地下空间开发中具有良好的优势。从热物性参... 详细信息

随着浅层地热能的大规模开发利用,针对地埋管地源热泵和能源地下结构的研究正由单个、单体尺度逐渐转向区域尺度。相较于地埋管地源热泵,能源地下结构占地面积小、成本低,在大规模城市建设及地下空间开发中具有良好的优势。从热物性参数和地下城市热岛效应两方面总结浅层地热能理论潜力现有研究成果,简述浅层地热能的开发形式,重点针对区域尺度地埋管地源热泵与能源地下结构的适应性评价进行系统综述,从适宜性分区、热交换潜力、满足建筑物能源需求效果三方面建立相应的区域尺度能源地下结构评价体系,以我国山东临朐县和德国巴登-符腾堡州地埋管地源热泵及我国南京大学仙林校区能量桩的区域性研究为案例进行深入分析,归纳当前研究中存在的问题,并对区域尺度能源地下结构的下一步研究进行展望。

关键词：地埋管地源热泵能源地下结构浅层地热能区域尺度评价

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Effects of Potassium-Solubilizing Bacteria on Growth, Antioxidant Activity and Expression of Related Genes in Fritillaria taipaiensis P. Y. Li

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Phyton-International Journal of Experimental Botany 2024年第4期93卷 789-806页

作者： Jiaqi Lang Mingyan Ye Ya Luo Yueheng Wang Zhifen Shi Xiaotian kong Xuan Li Nong Zhou Chongqing Engineering Laboratory of Green Planting and Deep Processing of Famous-Region Drug in the Three Gorges Reservoir Region College of Biology and Food EngineeringChongqing Three Gorges UniversityChongqing404120China College of Modern Chinese Medicine Industry Chengdu University of Traditional Chinese MedicineChengdu611130China College of Pharmacy Dali UniversityDali671000China

This study aimed to examine the effects of inoculating Fritillaria taipaiensis P.Y.Li leaves with different strains ofpotassium-solubilizing bacteria (KSB), or combinations thereof, focusing on aspects of photosynthesis and physiologicaland biochemical characteristics. At present, some studies have only studied the rhizosphere microbialcommunity characteristics of F. taipaiensis and have not discussed the effects of different microbial species on thegrowth promotion of F. taipaiensis. This paper will start from the perspective of potassium-solubilizing bacteria toconduct an in-depth study. Seed cultivation commenced at the base with three different KSBs in early October2022. The growth of F. taipaiensis leaves was observed after different treatments. Both single-plant and compoundinoculations were executed. A total of eight treatment groups were established, with aseptic fertilizer and sterilizedsoil functioning as the control group. The results reveal that intercellular CO_(2) concentration (ci), stomatal conductance(Gs), and transpiration rate (Tr) were at their apex in the S7 group. Most treatment groups exhibited anincrease in leaf area, photosynthetic pigment content, soluble sugar, soluble protein, Superoxide Dismutase(SOD), Peroxidase (POD), Catalase (CAT) activities, and proline content. The expression levels of POD, SOD,and CAT genes were evaluated, following inoculation with different KSB. The highest was the S7 group. Theinoculation with various KSB, or combinations thereof, appears to bolster the growth and development of F. taipaiensis.The composite inoculation group S7, comprising Bacillus cereus, Burkholderia cepacia, and Bacillus subtilis,manifested the most favorable impact on the diverse indices of F. taipaiensis, thereby furnishing valuableinsights for the selection of bacterial fertilizer in the artificial cultivation of F. taipaiensis.

关键词： Fritillaria taipaiensis bacteria antioxidant enzyme genes leaf physiology and biochemistry photosynthetic characteristics

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Association of accelerometer-measured sleep duration and different intensities of physical activity with incident type 2 diabetes in a population-based cohort study

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Journal of Sport and Health Science 2024年第2期13卷 222-232页

作者： Xinyi Jin Yilin Chen Hongliang Feng Mingqing Zhou Joey W.Y.Chang Yaping Liu Alice Pik Shan kong Xiao Tan Yun-Kwok Wing Yannis Yan Liang Jihui Zhang Guangdong Cardiovascular Institute Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080China Guangdong Provincial Key Laboratory of Coronary Heart Disease Prevention Guangdong Cardiovascular InstituteGuangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhou 510080China School of Medicine South China University of TechnologyGuangzhou 510641China Center for Sleep and circadian Medicine The Affiliated Brain Hospital of Guangzhou Medical UniversityGuangzhou 510180China The Second School of Clinical Medicine Southern Medical UniversityGuangzhou 510282China Guangdong Mental Health Center Guangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhou 510120China Li Chiu kong Family Sleep Assessment Unit Department of PsychiatryFaculty of MedicineThe Chinese University of Hong KongHong Kong 999077China Department of Psychiatry Faculty of MedicineThe Chinese University of Hong KongHong Kong 999077China Department of Medicine and Therapeutics Faculty of MedicineThe Chinese University of Hong KongHong Kong 999077China Department of Medical Sciences Uppsala UniversityUppsala 75185Sweden Department of Big Data in Health Science Zhejiang University School of Public HealthHangzhou 310058China Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China Guangzhou 510260China

Purpose:The aim of the current study was to investigate the association of accelerometer-measured sleep duration and different intensities of physical activity(PA)with the risk of incident type 2 diabetes in a population-based prospective cohort study.Methods:Altogether,88,000 participants(mean age=62.2±7.9 years,mean±SD)were included from the UK Biobank.Sleep duration(short:8 h/day)and PA of different intensities were measured using a wrist-won accelerometer over a 7-day period between 2013 and 2015.PA was classified according to the median or World Health Organization-recommendation:total volume of PA(high,low),moderate-to-vigorous PA(MVPA)(recommended,not recommended),and light-intensity PA(high,low).Incidence of type 2diabetes was ascertained using hospital records or death registries.Results:During a median follow-up of 7.0 years,1615 incident type 2 diabetes cases were documented.Compared with normal sleep duration,short(hazard ratio(HR)=1.21,95%confidence interval(95%ci):1.03-1.41)but not long sleep duration(HR=1.01,95%ci:0.89-1.15)was associated with excessive type 2 diabetes risk.This increased risk among short sleepers seems to be protected against by PA.Compared with normal sleepers with high or recommended PA,short sleepers with low volume of PA(HR=1.81,95%ci:1.46-2.25),not recommended(below the World Health Organization-recommended level of)MVPA(HR=1.92,95%ci:1.55-2.36),or low light-intensity PA(HR=1.49,95%ci:1.13-1.90)had a higher risk of type 2 diabetes,while short sleepers with a high volume of PA(HR=1.14,95%ci:0.88-1.49),recommended MVPA(HR=1.02,95%ci:0.71-1.48),or high light-intensity PA(HR=1.14,95%ci:0.92-1.41)did not.Conclusion:Accelerometer-measured short but not long sleep duration was associated with a higher risk of incident type 2 diabetes.A higher level of PA,regardless of intensity,potentially ameliorates this excessive risk.

关键词： Light physical activity Sleep duration Triaxial accelerometer Type 2 diabetes UK Biobank

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Effect of resistant starch supplementation on the diversity and composition of human gut microbiota: A systematic review and meta-analysis

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Food Science and Human Wellness 2024年

作者： Jiaxin Xu Haocun kong Caiming Li Xiaofeng Ban Zhaofeng Li Collaborative Innovation Center of Food Safety and Quality Control Jiangnan University School of Food Science and Technology Jiangnan University State Key Laboratory of Food Science and Technology Jiangnan University

Resistant starch (RS) has attracted much researchers’ attention because of its health-beneficial effects. Gut microbiota obviously shapes human health， but the effects of RS supplementation on the changes of human gut microbiota remain unclear. This observational meta-analysis aimed to reveal the effects of RS intake on alpha diversity and composition of gut microbiota through meta-analysis. Two independent authors systematically searched articles from inception until February 2023 on four electronic databases. Twenty-four highly relevant trials were included conforming to Preferred Reporting Items for Systematic reviews and Meta-Analysis protocol， and a total of 816 individuals were included. Significant heterogeneity analyses revealed that RS intake notably decreased Shannon index (WMD: –0.11; 95% ci: –0.21， –0.01)， and stimulated the composition of health promoting bacteria genera， including Bifidobacterium (WMD: 1.75; 95% ci: 0.39， 3.11; WMD: 0.36; 95% ci: 0.04， 0.69)， Faecalibacterium (WMD: 0.70; 95% ci: 0.20， 1.20; ES: 0.91; 95% ci: 0.60， 1.23)， and Prevotella (WMD: 0.35; 95% ci: 0.01， 0.69). Taken together， the present study revealed that changes in the gut microbiota diversity and genera were correlated with RS supplementation， which may contribute to benefits in human health.

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Effect of artificial natural light on the development of myopia among primary school-age children in China:a three-year longitudinal study

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 924-931页

作者： Hui-Min Cai Meng-Yan Li Yi Cao Yu-Lin Wu Ming Liang Yu-Shi Chen Bi-Kun Xian Yu-Juan Huang Xiang-Bin kong Department of Ophthalmology the Second People’s Hospital of FoshanAffiliated Foshan Hospital of Southern Medical UniversityFoshan 528000Guangdong ProvinceChina Guangdong Medical University Zhanjiang 524023Guangdong ProvinceChina Guangdong Cosio Lighting Corporation Foshan 528000Guangdong ProvinceChina

AIM:To assess the efficacy of artificial natural light in preventing incident myopia in primary school-age children.METHODS:This is a prospective,randomized control,intervention study.A total of 1840 students from 39 classes in 4 primary schools in Foshan participated in this study.The whole randomization method was adopted to include classes as a group according to 1:1 randomized control.Classrooms in the control group were illuminated by usual light,and classrooms in the intervention group were illuminated by artificial natural light.All students received uncorrected visual acuity and best-corrected visual acuity measurement,non-cycloplegic autorefraction,ocular biometric examination,slit lamp and strabismus examination.Three-year follow-up,the students underwent same procedures.Myopia was defined as spherical equivalent refraction≤-0.50 D and uncorrected visual acuitycidence rate of myopia was 26.4%(207 incident cases among 784 eligible participants at baseline)in the control group and 21.2%(164 incident cases among 774 eligible participants at baseline)in the intervention group[difference of 5.2%(95%ci,3.7%to 10.1%);P=0.035].There was also a significant difference in the three-year change in spherical equivalent refraction for the control group(-0.81 D)compared with the intervention group[-0.63 D;difference of 0.18 D(95%ci,0.08 to 0.28 D);Pci,0.01 to 0.09 mm);P=0.003].CONCLUSION:Artificial natural light in the classroom of primary schools can result in reducing incidence rate of myopia during a period of three years.

关键词： myopia artificial natural light school-age children efficacy

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A 5′tRNA-Ala-derived small RNA regulates anti-fungal defense in plants

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Science China(Life Sciences) 2022年第1期65卷 1-15页

作者： Hanqing Gu Bi Lian Yuxiang Yuan ci kong Yan Li Chang Liu Yijun Qi Center for Plant Biology School of Life SciencesTsinghua UniversityBeijing 100084China Tsinghua University-Peking University Joint Center for Life Sciences Tsinghua UniversityBeijing 100084China

Apart from their primordial role in protein synthesis,t RNAs can be cleaved to produce t RNA-derived small RNAs(ts RNAs).The biological functions of ts RNAs in plants remain largely unknown.In this study,we developed Rtc B ligation-based small RNA(s RNA)sequencing,a method that captures and distinguishes between 3′-2′,3′-cyclic-phosphate(c P)/phosphate(P)-terminated s RNAs and 3′-OH-terminated s RNAs,and profiled 5′ts RNAs and 5′t RNA halves in Arabidopsis thaliana.We found that Arabidopsis 5′ts RNAs and 5′t RNA halves predominantly contain a c P at the 3′end and require S-like RNase 1(RNS1)and RNS3 for their production.One of the most abundant 5′ts RNAs,5′ts R-Ala,by associating with AGO1,negatively regulates Cytochrome P45071 A13(CYP71 A13)expression and camalexin biosynthesis to repress anti-fungal defense.Interestingly,5′ts R-Ala is downregulated upon fungal infection.Our study provides a global view of 5′ts RNAs and 5′t RNA halves in Arabidopsis and unravels an important role of a 5′ts RNA in regulating anti-fungal defense.

关键词： tRNA-derived small RNAs small RNA sequencing RNase T2 CYP71A13 disease resistance

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基于神经影像学的常见神经系统疾病头针刺激靶点研究(上)

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针刺研究 2024年第6期49卷 650-660页

作者：张斌龙刘娇崔方圆曹瑾余思奕孔乔孔健中国中医科学院广安门医院北京100053 福建中医药大学福建省康复产业研究院福州350122 首都医科大学中医药学院北京100069 北京中医药大学东直门医院北京100700 北京中医药大学生命科学学院北京100029 成都中医药大学针灸推拿学院成都611137 哈佛医学院麻省总医院波士顿02129美国

目的:基于神经影像学研究,总结现代脑科学的研究成果,探索常见神经系统疾病的头针刺激靶点。方法:基于Neurosynth数据库平台(http://***/)进行神经影像学研究的Meta分析,识别神经系统疾病的头针与脑刺激靶点并投射至头皮表面,进一步结... 详细信息

目的:基于神经影像学研究,总结现代脑科学的研究成果,探索常见神经系统疾病的头针刺激靶点。方法:基于Neurosynth数据库平台(http://***/)进行神经影像学研究的Meta分析,识别神经系统疾病的头针与脑刺激靶点并投射至头皮表面,进一步结合传统头部腧穴和脑电10-20系统做出定位建议,结合靶区形态做出操作建议。文献检索于2022年7月30日进行。结果:研究结果分上下两篇阐述,本文为上篇,包括帕金森病、慢性疼痛、失语症、失读症。帕金森病识别出了7个潜在头针靶点,对应的布罗德曼区(BA)主要为BA6等;慢性疼痛识别出了10个潜在头针靶点,对应脑区主要为BA40等;失语症识别出了7个潜在头针靶点,对应脑区主要为BA22等;失读症识别出了10个潜在头针靶点,对应脑区主要为BA40等。本文提供了以上各潜在靶点的基于神经影像的定位与操作建议。结论:本研究为头针的临床应用及研究提供了一种基于现代影像学证据的常见神经系统疾病的刺激靶点。这些靶点也可用于神经(脑)刺激治疗相关疾病的探索中。

关键词：头针头针刺激靶点神经成像神经系统疾病脑刺激

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含氟废水中氟化钙颗粒结晶行为及其可浮性研究

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金属矿山 2024年第4期 121-126页

作者：张雨茜次曲李军霄孔令豪钱玉鹏黄鸶云刘东斌武汉理工大学资源与环境工程学院湖北武汉430070 矿物资源加工与环境湖北省重点实验室湖北武汉430070 关键非金属矿产资源绿色利用教育部重点实验室湖北武汉430070 中建三局绿色产业投资有限公司湖北武汉430056

为解决氟资源加工利用过程中的环境污染问题,并提高含氟废水中氟资源的综合利用率,系统研究了含氟酸性废水中形成的氟化钙结晶颗粒的沉降行为和粒度特征,探索了氟化钙结晶颗粒的浮选特性,并结合Visual MINTEQ软件模拟氟化钙化学沉淀形... 详细信息

为解决氟资源加工利用过程中的环境污染问题,并提高含氟废水中氟资源的综合利用率,系统研究了含氟酸性废水中形成的氟化钙结晶颗粒的沉降行为和粒度特征,探索了氟化钙结晶颗粒的浮选特性,并结合Visual MINTEQ软件模拟氟化钙化学沉淀形成过程,利用XRD表征结晶颗粒的物相组成,采用Zeta电位测试分析Na OL与氟化钙颗粒的作用机理。研究结果表明:用氯化钙处理含氟酸性废水时,在强酸条件下,无法形成氟化钙结晶颗粒;在p H>5时,能获得稳定的氟化钙结晶沉淀产物,且废水中F^(-)浓度越高,结晶颗粒数量越多,粒度越大,所获得氟化钙结晶纯度高,几乎不含其他杂质;油酸钠在p H为5~9时,能够吸附在氟化钙结晶颗粒表面,使其具备良好的可浮性,且油酸钠用量与废水中F^(-)浓度呈等比例关系,浮选回收效果良好。该研究结果可为处理含氟废水和回收氟化钙资源提供理论参考。

关键词：含氟酸性废水氟化钙结晶行为可浮性

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