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Standards and methods for dent assessment and failure prediction of pipelines:A critical review

Petroleum Science 2022年第6期19卷 3029-3045页

作者： Jian Zhao Yun-rong lv Y.Frank Cheng Dept.of Mechanical&Manufacturing Engineering University of CalgaryAlbertaT2N 1N4Canada Guangdong Provincial Engineering Technology Research Center of Petrochemical Corrosion and Safety Guangdong University of Petrochemical TechnologyMaomingGuangdongChina

Dent,a common mechanical damage on pipelines,is associated with a significant local plastic *** can cause pipeline failures,especially when they are combined with other types of defects such as gouges,fatigue,corrosion,and *** this work,a systematic review of various assessment methods and standards for pipeline dents,including the combination of a dent with other defects,is ***,the methods available today are not sufficiently accurate and reliable to assess pipeline dents,especially the dent-defect *** plain dents on pipelines,both the depthbased criterion and the strain-based criterion are commonly used in *** main problems include inaccuracy and *** a dent combined with other defects,the existing assessment techniques are not mature enough to give reliable *** experimental testing and numerical modeling through finite element(FE)analysis are capable of investigating the influence of dents and dent-defect combinations on burst failure pressure of the pipelines,although an approximation to the reality is still the main difficulty existing in the experimental testing and FE ***,relevant studies on assessment techniques for plain dents,a dent with fatigue and a dent with a single gouge have been common in *** combinations of a dent with corrosion or cracks have been rarely assessed due to complicated mechanisms involving a multi-physics coupling *** of novel assessment methods by integrating mechanical stress and strain,electrochemical reactions and steel metallurgy will be a key topic to accurately assess the dent-defect combinations for improved pipeline integrity.

关键词： Dents Pipelines Assessment techniques Burst failure pressure Dent-defect combinations

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Syntheses of novel series benzo [1,5] oxazepin-4-one-based compounds from 1,5-difluoro-2,4-dinitrobenzene

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Chinese Chemical Letters 2008年第9期19卷 1021-1023页

作者： Li Qiu Wang Qing Shan Li Xin Pu Wei Wei Nie Xiao Fei lv Qiu rong Li Yanshan University Qinhuangdao 066004 China

A novel benzo [ 1,5] oxazepin-4-one skeleton compound and its four derivatives were synthesized effectively from 1,5-difluoro- 2,4-dinitrobenzene （DFDNB） under mild conditions. In the process, four intermediates were synthesized by substitutions of the two fluorine atoms and reductions of the meta-dinitro groups in DFDNB respectively. The results showed that the key for synthesizing the intermediates was the substitution of one of the two fluorine atoms in DFDNB by 3-hydroxy butyric acid ethyl ester first, then the other fluorine atom by morpholine, and then the reduction of the meta-dinitro groups in the substitute by HCOONH4 with Pd/C. The products were purified with silica gel column chromatography, and confirmed by HPLC, LC-MS and 1H NMR. They should contribute to construct the molecular libraries for therapeutic applications.

关键词： Syntheses Benzo oxazepin derivatives DFDNB Substitution Reduction

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Metabolic syndrome and its association with components of sarcopenia in older community-dwelling Chinese

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The Journal of Biomedical Research 2022年第2期36卷 120-126页

作者： Qiangwei Tong Xiao Wang Yunlu Sheng Shu Chen Bin Lai rong lv Jing Yu Division of Geriatric Endocrinology Department of Geriatricsthe First Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu 210029China Department of Geriatrics Suzhou Ninth People's HospitalSuzhouJiangsu 215200China

Aging and obesity contribute to muscle dysfunction. This study aimed to determine the cross-sectional associations between components of metabolic syndrome (MetS) and sarcopenia in 251 older community- dwelling Chinese. The total fat-free mass was measured by dual-energy X-ray absorptiometry, muscle strength (handgrip strength) by a handheld dynamometer, physical performance by 4-meter walk, 5-time chair stand test, and the short physical performance battery (SPPB). MetS was defined using the International Diabetes Federation (IDF) criteria. The participants with MetS had a higher appendicular skeletal muscle mass (ASM) and relative ASM (RASM). The males with MetS had higher handgrip strength, and the females with MetS had higher SPPB scores. After adjusting for age and body mass index, the participants with an increased waist circumference had a higher ASM, and those with increased diastolic blood pressure (DBP) also had higher handgrip strength. The males with elevated fasting blood glucose (FBG) levels had a lower gait speed. Components of MetS, such as DPB and FBG, were associated with muscle strength and physical performance in older adults. These results suggest that muscle strength and function should be considered in treating older adults with MetS.

关键词： metabolic syndrome sarcopenia community-dwelling older Chinese

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MicroRNA-15a/b are up-regulated in response to myocardial ischemia/reperfusion injury

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Journal of Geriatric Cardiology 2012年第1期9卷 28-32页

作者： Li-Feng Liu Zhuo Liang Zhen-rong lv Xiu-Hua Liu Jing Bai Jie Chen Chen Chen Yu Wang Institute of Geriatric Cardiology Chinese PLA General Hospital 28 Fuxing Road Beijing 100853 China Department of Cardiology Xijing Hospital the Fourth Military Medical University 17 Changle Road Xi'an 710032 Shaanxi China Cardiovascular Research Institute and Department of Cardiology Shenyang Northern Hospital 83 Wenhua Road Shenyang 110016 Liaoning China Department of Pathophysiology Shandong University School of Medicine Jinan 250012 Shandong China Department of Pathophysiology Chinese PLA General Hospital 28 Fuxing Road Beijing 100853 China

Objective Several studies have indicated that miR-15a,miR-15b and miR-16 may be the important regulators of *** attenuate apoptosis could protect myocardium and reduce infarction size,the present study was aimed to find out whether these miRNAs participate in regulating myocardial ischemia reperfusion （I/R） *** Apoptosis in mice hearts subjected to I/R was detected by TUNEL assay in vivo,while flow cytometry analysis followed by Annexin V/PI double stain in vitro was used to detect apoptosis in cultured cardiomyocytes which were subjected to hypoxia/reoxygenation （H/R）.Taqman real-time quantitative PCR was used to confirm whether miR-15a/15b/16 were involved in the regulation of cardiac I/R and H/*** Compared to those of the controls,I/R or H/R induced apoptosis of cardiomyocytes was significantly iucreased both in vivo （24.4％ ± 9.4％ vs.2.2％ ± 1.9％,P ＜ 0.01,n =5） and in vitro （14.12％ ±0.92％ vs.2.22％ ± 0.08％）.The expression of miR-15a and miR-15b,but not miR-16,was increased in the mice I/R model,and the results were consistent in the H/R *** Our data indicate miR-15 and miR-15b are up-regulated in response to cardiac I/R injury,therefore,down-regulation of miR- 15a/b may be a promising strategy to reduce myocardial apoptosis induced by cardiac I/R injury.

关键词： miR-15a/b Apoptosis Myocardial reperfusion injury Ischemia/Reperfusion injury

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Novel variants in DNAH6 cause male infertility associated with multiple morphological abnormalities of the sperm flagella(MMAF)and ICSI outcomes

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Asian Journal of Andrology 2024年第1期26卷 91-98页

作者： Zhong-Mei Shao Yu-Tong Zhu Meng Gu Sen-Chao Guo Hui Yu Kuo-Kuo Li Dong-Dong Tang Yu-Ping Xu Ming-rong lv Reproductive Medicine Center Department of Obstetrics and Gynecologythe First Affiliated Hospital of Anhui Medical UniversityHefei 230022China Department of Obstetrics and Gynecology Fuyang Hospital of Anhui Medical UniversityFuyang 236112China NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract(Anhui Medical University) Hefei 230032China Key Laboratory of Population Health Across Life Cycle(Anhui Medical University) Ministry of Education of the People'sRepublicof ChinaHefei 230032China

Variations in the dynein axonemal heavy chain gene,dynein axonemal heavy chain 6(DNAH6),lead to multiple morphological abnormalities of the *** studies have reported that these deficiencies may result in sperm head ***,whether DNAH6 is also involved in human acrosome biogenesis remains *** purpose of this study was to investigate DNAH6 gene variants and their potential functions in the formation of defective sperm heads and ***-exome sequencing was performed on a cohort of 375 patients with asthenoteratozoospermia from the First Affiliated Hospital of Anhui Medical University(Hefei,China).Hematoxylin and eosin staining,scanning electron microscopy,and transmission electron microscopy were performed to analyze the sperm morphology and *** staining and Western blot analysis were conducted to examine the effects of genetic *** identified three novel deleterious variants in DNAH6 among three unrelated *** absence of inner dynein arms and radial spokes was observed in the sperm of patients with DNAH6 ***,deficiencies in the acrosome,abnormal chromatin compaction,and vacuole-containing sperm heads were observed in these patients with DNAH6 *** decreased levels of the component proteins in these defective structures were further confirmed in sperm from patients with DNAH6 variants using Western *** intracytoplasmic sperm injection(ICSl)treatment,the partner of one patient with a DNAH6 variant achieved successful ***,novel variants in DNAH6 genes that contribute to defects in the sperm head and flagella were identified,and the findings indicated Icsl as an effective clinical treatment for such patients.

关键词： asthenoteratospermia DNAH6 intracytoplasmic sperm injection male infertility

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Influencing factors and preventive measures of infectious complications after intestinal resection for Crohn’s disease

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World Journal of Gastrointestinal Surgery 2024年第10期16卷 3363-3370页

作者： Shi-rong lv Xiao Huang Li-Yun Zhou Jie Shi Chu-Chu Gong Ming-Ke Wang Ji-Shun Yang Naval Medical Center of PLA Naval Medical UniversityShanghai 200052China

The incidence of Crohn’s disease(CD)has increased in recent years,with most patients requiring intestinal *** after intestinal resection for CD can lead to poor prognosis and recurrence,among which infectious complic-ations are the most *** study aimed to investigate the common risk factors,including medications,preoperative nutritional status,surgery-related factors,microorganisms,lesion location and type,and so forth,causing infectious complications after intestinal resection for CD,and to propose corresponding preventive *** findings provided guidance for identifying suscept-ibility factors and the early intervention and prevention of infectious complic-ations after intestinal resection for CD in clinical practice.

关键词： Crohn’s disease Intestinal resection Postoperative infectious complications Influencing factors Preventive measures

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Anion Effects on the Low Frequency Intermolecular Vibrations of Water in Aqueous Potassium Salt Solutions

Anion Effects on the Low Frequency Intermolecular Vibrations...

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第十三届全国化学动力学会议

作者： rong lv Mengqi Hou Anchi Yu Department of Chemistry Renmin University of China

＜正＞Great efforts have been put into aqueous salt solutions to unravel their nature for several decades. However, some basic questions remain open as including ion solvation, hydrogen bond （HB） structure maker and...

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卫星ATM网络中跨层设计的星上缓存管理优化方案

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宇航学报 2005年第6期26卷 682-686,742页

作者：吕蓉曹志刚清华大学电子工程系微波与数字通信国家重点实验室北京100084

为提高卫星ATM(异步传递方式)网络星上缓存资源的利用率,针对利用上层协议重传的非实时数据业务,采用跨层设计方法提出了一种缓存管理优化方案—错误信元尾丢弃(ECTD)。它把信道误码引起的错误信元及后续的属于同一协议数据单元的无效... 详细信息

为提高卫星ATM(异步传递方式)网络星上缓存资源的利用率,针对利用上层协议重传的非实时数据业务,采用跨层设计方法提出了一种缓存管理优化方案—错误信元尾丢弃(ECTD)。它把信道误码引起的错误信元及后续的属于同一协议数据单元的无效信元丢弃。以早分组丢弃为基础,进一步建立了采用ECTD和不采用ECTD的分析有效吞吐量的数学模型。数值分析结果表明,ECTD具有优化缓存管理、提高有效吞吐量的作用,而且信元错误率和协议数据单元的长度越大,ECTD对有效吞吐量的改善就越明显。

关键词：卫星通信异步传递方式缓存管理跨层设计错误信元尾丢弃

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卫星通信网络中的跨层设计

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电子学报 2005年第B12期33卷 2435-2440页

作者：吕蓉曹志刚清华大学电子工程系微波与数字通信国家重点实验室北京100084

随着通信技术的发展，各种多媒体应用被引入到无线和卫星网络，然而由于无线及卫星网络的信道特性并不理想，传统的分层设计方法对于无线环境来说有相当大的局限性，因此近年来另外一个设计方法——跨层设计成为了一个研究热点．本文首... 详细信息

随着通信技术的发展，各种多媒体应用被引入到无线和卫星网络，然而由于无线及卫星网络的信道特性并不理想，传统的分层设计方法对于无线环境来说有相当大的局限性，因此近年来另外一个设计方法——跨层设计成为了一个研究热点．本文首先简单介绍了跨层设计方法的背景、思路，之后论述了该方法在卫星通信网络中的应用，最后分析讨论了跨层设计的特点、代价和折衷．

关键词：卫星通信网络跨层设计分层设计服务质量体系结构

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Long-read genome assemblies reveal a cis-regulatory landscape associated with phenotypic divergence in two sister Siniperca fish species

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Zoological Research 2023年第2期44卷 287-302页

作者： Guang-Xian Tu Xin-Shuang Zhang Rui-Run Jiang Long Zhang Cheng-Jun Lai Zhu-Yue Yan Yan-rong lv Shao-Ping Weng Li Zhang Jian-Guo He Muhua Wang State Key Laboratory for Biocontrol School of Marine SciencesSun Yat-sen UniversityZhuhaiGuangdong 519000China China-ASEAN Belt and Road Joint Laboratory on Mariculture Technology Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)ZhuhaiGuangdong 519000China Chinese Institute for Brain Research Beijing 102206China Guangdong Province Key Laboratory for Aquatic Economic Animals School of Life SciencesSun Yat-sen UniversityGuangzhouGuangdong 510275China

Due to the difficulty in accurately identifying structural variants(SVs) across genomes,their impact on cisregulato ry diverge n ce of closely related species,especially fish,remains to be *** identified broad H3K4me3 domains are essential for the regulation of genes involved in several biological ***,the role of broad H3K4me3 domains in phenotypic divergence remains poorly *** chuatsi and *** are closely related but divergent in several phenotypic traits,making them an ideal model to study cis-regulatory evolution in sister ***,we generated chromosome-level genomes of *** and ***,with assembled genome sizes of 716.35 and740.54 Mb,*** evolutionary histories of *** and *** were studied by inferring dynamic changes in ancestral population *** explore the genetic basis of adaptation in *** and ***,we performed gene family expansion and contraction analysis and identified positively selected genes(PSGs).To investigate the role of SVs in cis-regulatory divergence of closely related fish species,we identified high-quality SVs as well as divergent H3K27ac and H3K4me3 domains in the genomes of *** and *** analysis revealed that cis-regulatory divergence caused by SVs played an essential role in phenotypic divergence between *** and ***,divergent broad H3K4me3 domains were mostly associated with cancer-related genes in *** and *** and contributed to their phenotypic divergence.

关键词： cis-regulatory divergence Structural variants H3K27ac Broad H3K4me3 Siniperca chuatsi Siniperca scherzeri

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