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MODEL STUDY ON PREVENTING SEDIMENT DEPOSSITION IN WATER INTAKE SYSTEM

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Journal of Hydrodynamics 1997年第4期9卷 82-87页

作者： Wang xing-kui, yang mei-qingDept. of Hydraulic Engineering, Tsinghua University, Beijing 100084, P. R. China

The hydraulic and sediment deposition problems in the water intake system of a pumping house were studied by physical model. The experimental results of different working cases indicate that the sediment depositions at the gates, stilling basin and culverts are very few when the system was normally operated, but in the forebay of pumping house, especially in the pumping house for living water, the amount of sediment deposition sometimes is considerably large. At the front of the entry of pumping house for living water, installing a set of oblique pipes can prevent the coarse grains to enter it, the deposition amount will obviously decrease.

关键词： model study intake water sediment deposition

中国老年人午睡时长和夜间睡眠与抑郁症状的关联:基于2020年CHARLS数据的实证分析

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中国全科医学 2025年第5期28卷 560-567页

作者：周梅杨爱琼邢英王玉玲新疆医科大学第一附属医院干部保健中心新疆维吾尔自治区乌鲁木齐市830054

背景随着我国进入中度老龄化社会,老年人心理健康问题逐年增加,而生活习惯与老年人的心理健康密切相关。目的探讨我国老年人午睡时长、夜间睡眠与抑郁症状的关系,基于生活习惯角度推荐睡眠时间,为老年人抑郁早期防控提供科学依据。方法... 详细信息

背景随着我国进入中度老龄化社会,老年人心理健康问题逐年增加,而生活习惯与老年人的心理健康密切相关。目的探讨我国老年人午睡时长、夜间睡眠与抑郁症状的关系,基于生活习惯角度推荐睡眠时间,为老年人抑郁早期防控提供科学依据。方法基于2023-11-16公开发布第五轮(2020年)中国健康与养老追踪调查项目(CHARLS),纳入符合研究标准的8233名为研究对象。采用抑郁评定量表(CSE-D10)评估老年人抑郁症状,午睡时长划分5级:不午睡、<30 min、30~59 min、60~89 min、≥90 min,夜间睡眠分为5级:≥8 h、7~<8 h、6~<7 h、5~<6 h、<5 h。采用多因素Logistic回归分析探究影响老年人发生抑郁症状的因素,随机森林模型分析午睡时长、夜间睡眠在老年人发生抑郁症状中的重要程度,限制性立方样条曲线进一步探索午睡时长、夜间睡眠时长与抑郁症状发生风险之间的剂量-反应关系。结果2020年调查期间,中国老年人抑郁症状的发生率为24.84%(2045/8233)。多因素Logistic回归分析结果显示,午睡时长30~59 min是老年人发生抑郁症状的保护因素(OR=0.814,95%CI=0.673~0.985,P=0.034),夜间睡眠时间<5 h是老年人发生抑郁症状的危险因素(OR=1.705,95%CI=1.435~2.027,P<0.001)。女性、未婚/分居/离异/丧偶、失能、身体疼痛、强度体力活动、自评健康状况下降、生活满意度下降、卒中、帕金森病会增加老年人发生抑郁症状的风险(P<0.05)。随机森林模型显示,午睡时长、夜间睡眠时间对抑郁症状影响的重要性较高。午睡时长与发生抑郁症状之间存在非线性关系(P_(nonlinear)<0.05),老年人发生抑郁症的风险在午睡时长30 min后随着时间的增加而持续降低,最低水平约为50 min,午睡时长超过75 min后抑郁症状的发生风险会增加。老年人患抑郁症状的发生风险在夜间睡眠6 h后随着时间的增加而持续降低,最低水平约为7 h,睡眠时间超过9 h后抑郁的风险会增加(Poverall<0.05)。结论中国老年人群抑郁症的患病率较高(24.84%),午睡时长、夜间睡眠的持续时间与抑郁症之间呈J型关系,建议老年人每天午睡30~75 min,适度的午睡时长有效降低老年人发生抑郁症状的风险,同时夜间睡眠6~9 h降低抑郁症状的发生风险,对老年人群抑郁症的早期防控具有一定的意义。

关键词：抑郁老年人午睡时长夜间睡眠中国健康与养老追踪调查项目

Thermoelastic stress analysis of multilayered films in a micro-thermoelectric cooling device

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Acta Mechanica Sinica 2012年第6期28卷 1644-1650页

作者： Yu-mei yang xing-Zhe Wang Wen-Jie Zhang Key Laboratory of Mechanics on Environment and Disaster in Western China The Ministry of Education of China College of Civil Engineering and Mechanics Lanzhou University

This paper presents an analytical solution for the thermoelastic stress in a typical in-plane＇s thin-film micro- thermoelectric cooling device under different operating con- ditions. The distributions of the permissible temperature fields in multilayered thin-films are analytically obtained, and the characteristics, including maximum temperature dif- ference and maximum refrigerating output of the thermo- electric device, are discussed for two operating conditions. Analytical expressions of the thermoelastic stresses in the layered thermoelectric thin-films induced by the tempera- ture difference are formulated based on the theory of mul- tilayer system. The results demonstrate that, the geometric dimension is a significant factor which remarkably affects the thermoelastic stresses. The stress distributions in layers of semiconductor thermoelements, insulating and support- ing membrane show distinctly different features. The present work may profitably guide the optimization design of high- efficiency micro-thermoelectric cooling devices.

关键词： Thermoelectric cooling device Multilayeredthin-film Thermoelastic stress - Analytical solution

Silver(I) Oxide Mediated Regioselective Monoacylation of 2,4-Dihydroxyls in L-Rhamnopyranosides

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Chinese Chemical Letters 2006年第8期17卷 1009-1012页

作者： Qian yang xing mei ZHU Jin Song yang Ministry of Education Key Laboratory of Drug Targeting School of Pharmacy Sichuan University Chengdu 610041

A series of acyls （Ac, Bz and Ts） were introduced regioselectively to the 2-hydroxyl in methyl and ally 3-O-benzyl-α-L-rhamnopyranosides mediated by silver（I） oxide in the presence of a catalytic amount of potass... 详细信息

关键词： Silver(Ⅰ) oxide acylation regioselectivity,α-L-rhamnopyranoside.

Determining beam transverse absolute position by triangulation of multi-electrode signal phase differences

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Nuclear Science and Techniques 2024年第8期35卷 38-47页

作者： xing yang Hong‑Shuang Wang Yi‑mei Zhou Yong‑Bin Leng Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China University of Science and Technology of China Hefei 230026China

Accurate measurement of the transverse position of a beam is crucial in particle accelerators because it plays a key role in determining the beam *** methods for beam-position measurement rely on the detection of image currents induced on electrodes or narrow-band wake field induced by a beam passing through a cavity-type ***,these methods have *** indirect measurement of multiple parameters is computationally complex,requiring external calibration to determine the system parameters in ***,the utilization of the beam signal information is ***,this study proposes a novel method for measuring the absolute electron beam transverse *** utilizing the geometric relationship between the center position of the measured electron beam and multiple detection electrodes and by analyzing the differences in the arrival times of the beam signals detected by these electrodes,the absolute transverse position of the electron beam crossing the electrode plane can be *** method features absolute position measurement,a position sensitivity coefficient independent of vacuum chamber apertures,and no requirement for a symmetrical detector electrode *** feasibility of this method is validated through numerical simulations and beam experiments.

关键词： Electron beam bunch-by bunch diagnostics Bunch position measurement Triangulation method Bunch phase Bunch-by-bunch Transverse position Pickup signal

Congenital fiber-type disproportion presenting with type II respiratory failure after delivery:A case report

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World Journal of Clinical Cases 2021年第7期9卷 1748-1754页

作者： Hong-mei yang Jian-xing Guo Yi-Min yang Department of Intensive Care Unit The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina

BACKGROUND Congenital fiber-type disproportion(CFTD)is a form of congenital *** is rare,especially when presenting in patients with critical ***,we report a case of CFTD presenting with type II respiratory failure after delivery and provide a review of the literature on *** SUMMARY A 30-year-old woman was admitted to the obstetrics department of our hospital with premature rupture of the fetal membrane and with 7 h of regular *** delivery,the patient experienced a refractory type II respiratory *** examination along with diagnostic procedures such as electromyography and biopsy confirmed *** of invasive ventilator followed by intermittent use of noninvasive ventilator attenuated her *** patient recovered after ventilator-assisted respiration and was weaned off the noninvasive ventilator on the seventh day *** Congenital myopathy should be considered a differential diagnosis for type II respiratory failures that cannot be attributed to other diseases.

关键词： Congenital fiber-type disproportion Congenital myopathy Type II respiratory failure Delivery Systematic review Case report

Research progress on short-term mechanical properties of FRP bars and FRP-reinforced concrete beams

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 245-270页

作者： Lili xing Shengjiang Sun Kuihua mei Yiping Guo Zhenhong yang School of Highway Chang'an UniversityXi'an 710064China

Fiber-reinforced polymer(FRP)bars have been increasingly recognized in the field of civil engineering due to their advantages of light weight,high strength and excellent *** bars can replace steel bars in concrete beams and effectively improve the durability of *** this paper,the literature relevant to the short-term mechanical properties of FRP bars and FRP-reinforced concrete beams was reviewed based on previous studies and practical engineering ***,the mechanical properties of FRP bars were *** types of fibers or steel and fibers can be combined to obtain hybrid fiber-reinforced polymer(HFRP)or steel-fiber composite bars(SFCB)with excellent mechanical performance,*** bond performance and bond-slip model between FRP bars and concrete were *** common bond-slip models were usually used to study the bond performance between carbon fiber-reinforced polymer(CFRP)bars or glass fiber-reinforced polymer(GFRP)bars and concrete,but changing the type of FRP bars will lead to larger ***,the experimental studies,theoretical calculation methods and finite element simulation methods of flexural/shear behavior of FRP-reinforced concrete beams were ***,their applications in practical engineering were discussed and the prospects of further research were *** is pointed out that FRP-reinforced ultra-high performance concrete(UHPC)beams,FRP-reinforced geopolymer concrete(GPC)beams,engineered cementitious composites(ECC)-FRP-reinforced concrete beams,prestressed FRP-reinforced concrete beams and steel/FRP hybrid-reinforced concrete beams can effectively improve the deformation resistance and poor ductility of pure FRP-reinforced concrete beams.

关键词： FRP bars Bond performance Flexural/shear behavior Civil engineering

汉防己甲素对肾小球硬化大鼠肾皮质IV型胶原基因表达的影响

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泰山医学院学报 2001年第1期22卷 18-19页

作者：董兴刚安增梅杨海春上海市第二人民医院肾内科上海200011

目的　探讨中药汉防己甲素 (Tetrandrine)对单侧肾切除加两次注射阿霉素肾小球硬化大鼠肾皮质IV型胶原基因表达的作用。方法　将实验动物分为 :正常对照组、汉防己甲素治疗组、氨氯地平治疗对照组和模型组 ,于第 12周留取尿标本。肾组... 详细信息

目的　探讨中药汉防己甲素 (Tetrandrine)对单侧肾切除加两次注射阿霉素肾小球硬化大鼠肾皮质IV型胶原基因表达的作用。方法　将实验动物分为 :正常对照组、汉防己甲素治疗组、氨氯地平治疗对照组和模型组 ,于第 12周留取尿标本。肾组织病理学检查、用Northernblot杂交检测皮质IV型胶原基因表达mRNA表达。结果　汉防己甲素治疗组和氨氯地平治疗对照组 ,肾病理损伤减轻 ,肾皮质IV型胶原mRNA表达下调。结论　汉防己甲素可延缓肾小球硬化。

关键词：汉防己甲素肾小球化 IV型胶原基因表达

Comparative transcriptomic analysis of larval and adult Malpighian tubules from the cotton bollworm Helicoverpa armigera

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Insect Science 2018年第6期25卷 991-1005页

作者： Yi-yang Yuan mei Li Fan Fan xing-Hui Qiu State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijingChina College of Plant Protection Hebei Agricultural UniversityBaodingHebei ProvinceChina

Malpighian tubules (MTs)are moregulatory organs of ***, usually considered the key excretory and os- increasing evidence has suggested that MTs perform many more functions than just *** now,the molecular and physiological functions of MTs in the cotton bollworm (Helicoverpa armigera),a very important agricultural pest,are largely *** this study,the transcriptomes of H. armigera MTs from larvae,male adults and female adults were sequenced using RNA-Seq technology,and comparative analyses of transcriptomes between two life stages (larval and adult)and between adult sexes were *** generated a total of 84 643 high-quality unigenes,and identified a large number of abundant transcripts putatively encoding proteins involved in diuresis,detoxification,immunity,carbohydrate transport and metabolism,development and *** found that the expression pattern of unigenes was relatively similar between female and male adult MTs,but different between larval and adult *** data suggest that insect MTs may take multiple physiological fimctions as versatile *** extensive alterations in gene expression in MTs occurred from larvae to adults reflect an ecological adaptation to different feeding *** dimorphism in the cotton bollworm is somewhat indicated by the transcriptional difference of genes related to carbohydrate metabolism,detoxification,immunity and reproduction in the MTs of male and female adults.

关键词： ecological adaptation Helicoverpa armigera Malpighian tubules sexual dimorphism transcriptome