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Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1681-1688页

作者： Jinshan He zhengrong yu Longfei Li Xitao Wang Qiang Feng Beijing Advanced Innovation Center for Material Genome Engineering Collaborative Innovation Center of Steel TechnologyUniversity of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Material Genome Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology BeijingBeijing 100083China Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

In the present study,the effect of grit blasting and subsequent heat treatment on the stress rupture properties of a thirdgeneration nickel-based single-crystal superalloy SGX3 sheet was studied.It was found that the stress rupture life of alloy SGX3 sheet at 980℃/250 MPa was reduced by about 60%by only vacuum heat treatment at 1100℃ for 200 h and further reduced by 20%and 70%respectively with grit blasting of 0.3 MPa/1 min and 0.5 MPa/2 min before heat treatment.The microstructure analysis results indicated that the degradation of stress rupture life of alloy SGX3 sheet by vacuum heat treatment was mainly attributed to the variation ofγ/γ′microstructure,i.e.,the decrease inγ′volume fraction and the coarsening ofγ′precipitates.Furthermore,such degradation by grit blasting and subsequent vacuum heat treatment should be attributed to the formation of cellular recrystallization with different thicknesses at the surface of alloy SGX3 sheet,which not only acts as the vulnerable site for cracks to initiate and propagate but also reduces the effective loading area.

关键词： Ni-based single-crystal superalloy Creep life Degradation Recrystallization

Single-nucleus profiling unveils a geroprotective role of the Foxo3 in primate skeletal muscle aging

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Protein & Cell 2023年第7期14卷 499-514页

作者： Ying Jing yuesheng Zuo Yang yu Liang Sun zhengrong yu Shuai Ma Qian Zhao Guoqiang Sun Huifang Hu Jingyi Li Daoyuan Huang Lixiao Liu Jiaming Li Zijuan Xin Haoyan Huang Juan Carlos Izpisua Belmonte Weiqi Zhang Si Wang Jing Qu Guang-Hui Liu State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Advanced Innovation Center for Human Brain Protection National Clinical Research Center for Geriatric DisordersXuanwu Hospital Capital Medical UniversityBeijing 100053China University of Chinese Academy of Sciences Beijing 100049China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China China National Center for Bioinformation Beijing 100101China Aging Translational Medicine Center Intemational Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijing 100053China Department of Obstetrics and Gynecology Center for Reproductive MedicinePeking University Third HospitalBeijing 100191China The Key Laboratory of Geriatrics Beijing Institute of GeriatricsInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing Hospital/National Center of Gerontology of National Health CommissionBeijing 100730China Clinical Stem Cell Research Center Peking University Third HospitalBeijing 100191China Department of Orthopaedics Peking University First HospitalBeijing 100034China Sino-Danish College University of Chinese Academy of SciencesBeijing 101408China Sino-Danish Center for Education and Research Beijing 101408China Altos Labs Inc.San DiegoCA 94022USA The Fifth People's Hospital of Chongqing Chongqing 400062China

Age-dependent loss of skeletal muscle mass and function is a feature of sarcopenia,and increases the risk of many aging-related metabolic diseases.Here,we report phenotypic and single-nucleus transcriptomic analyses of non-human primate skeletal muscle aging.A higher transcriptional fluctuation was observed in myonuclei relative to other interstitial cell types,indicating a higher susceptibility of skeletal muscle fiber to aging.We found a downregulation of Foxo3 in aged primate skeletal muscle,and identi-fied FOxo3 as a hub transcription factor maintaining skeletal muscle homeostasis.Through the establishment of a complementary experimental pipeline based on a human pluripotent stem cell-derived myotube model,we revealed that silence of Foxo3 accelerates human myotube senescence,whereas genetic activation of endogenous FOxO3 alleviates human myotube aging.Altogether,based on a combination of monkey skeletal muscle and human myotube aging research models,we unraveled the pivotal role of the FOxO3 in safeguarding primate skeletal muscle from aging,providing a comprehensive resource for the development of clinical diagnosis and targeted therapeutic interventions against human skeletal muscle aging and the onset of sarcopenia along with aging-relateddisorders.

关键词： single-nucleus RNA sequencing primate aging skeletal muscle FOxO3

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延迟性肌肉酸痛与运动性骨骼肌记忆

中国组织工程研究 2024年第11期28卷 1762-1766页

作者：白峥嵘孙羽张振显潘诗农延安市人民医院CT诊断科陕西省延安市716000 中国医科大学附属盛京医院放射科辽宁省沈阳市110000 锦州医科大学附属第一医院辽宁省锦州市121000

背景:不习惯的运动使骨骼肌损伤,但可以产生一种减轻肌肉再损伤减轻疼痛的特定训练效果-肌肉记忆。目的:基于延迟性肌肉酸痛的病因,综述延迟性肌肉酸痛中骨骼肌记忆的存在及其可能机制,提出防治延迟性肌肉酸痛的新见解。方法:第一作者以... 详细信息

背景:不习惯的运动使骨骼肌损伤,但可以产生一种减轻肌肉再损伤减轻疼痛的特定训练效果-肌肉记忆。目的:基于延迟性肌肉酸痛的病因,综述延迟性肌肉酸痛中骨骼肌记忆的存在及其可能机制,提出防治延迟性肌肉酸痛的新见解。方法:第一作者以“DOMS,Skeletal muscle memory,Exercise Skeletal muscle adaptation,Repeat turn effect,exercise and autophagy,Autophagy and inflammation”为英文检索词,“延迟性肌肉酸痛,骨骼肌记忆,运动性骨骼肌适应,重复回合效应,运动与自噬,自噬与炎症”为中文检索词,检索PubMed、Embase、Web of Science、中国知网及万方数据库1990年1月至2022年12月发表的相关文献,最终纳入102篇文献进行综述。结果与结论:目前认为延迟性肌肉酸痛是由于代谢紊乱、机械损伤和氧化应激所致的急性期炎症反应,而运动性骨骼肌记忆具有减轻延迟性肌肉酸痛、减轻运动再损伤的作用,当离心训练的持续时间、频率和强度逐渐增加时,损伤症状可以被最小化,甚至可以避免。因此基于运动性骨骼肌记忆机制,寻找防治或减轻延迟性肌肉酸痛及运动性肌肉损伤的方法是未来的研究方向。综述的主要目的:①明确运动性骨骼肌记忆的存在;②探讨运动性骨骼肌记忆的可能机制,并提出该记忆与骨骼肌自噬的关系;③通过改善骨骼肌自噬水平为延迟性肌肉酸痛的防治提供新策略。

关键词：运动性肌肉损伤延迟性肌肉酸痛骨骼肌记忆骨骼肌适应重复回合效应运动-自噬自噬-炎症

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某矿井下多工作面协同爆破智能管控体系研究

有色金属工程 2024年第6期14卷 108-115页

作者：张西良李龙福崔正荣汪禹王春马鞍山矿山研究院爆破工程有限责任公司安徽马鞍山243000 河南理工大学能源科学与工程学院河南焦作454003

基于某矿穿孔和爆破工序分割、多中段多工作面同时作业的工程背景,采用跟踪调研的方法得出该矿具有爆破作业管控难度大、工序反馈衔接不及时、有效作业人员占比小等问题。为解决上述难题,采用工序分析、问题提出、风险评估等层层递进的... 详细信息

基于某矿穿孔和爆破工序分割、多中段多工作面同时作业的工程背景,采用跟踪调研的方法得出该矿具有爆破作业管控难度大、工序反馈衔接不及时、有效作业人员占比小等问题。为解决上述难题,采用工序分析、问题提出、风险评估等层层递进的方法,开展井下多工作面协同爆破智能管控体系研究。结果表明:井下爆破作业各工序间具有严谨的先后顺序;爆破器材运输和装药工序的危险程度最高,需精准管控;采用智能软件协同监管多工作面爆破作业工序,不仅精准管控效率高,还可降低矿山爆破作业的事故机率。最后结合某矿的实际作业条件,基于多工作面同时爆破作业的先后流程,采用Python语言开发了井下多工作面协同爆破智能管控软件,并通过爆破作业工作面的管理调试,证明研发的管控软件适合辅助该矿爆破工序的监管。

关键词：铁矿多工作面爆破工序智能管控软件

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非均质致密储层水平井分段压裂裂缝扩展模拟

大庆石油地质与开发 2024年第2期43卷 53-60页

作者：陈峥嵘齐宇韩磊房茂军王波谢昕孙乐李昊樊伟鹏中海油研究总院有限责任公司北京100028 中国石油大学(华东)石油工程学院山东青岛266580

针对非均质致密储层水平井分段压裂时裂缝的扩展延伸导致不同压裂缝簇产量差异大的问题,在考虑压裂液排量、黏度和地应力特征的情况下,开展非均质致密储层真三轴水力压裂实验和数值模拟研究,分析非均质岩石水平井分段压裂多裂缝扩展规... 详细信息

针对非均质致密储层水平井分段压裂时裂缝的扩展延伸导致不同压裂缝簇产量差异大的问题,在考虑压裂液排量、黏度和地应力特征的情况下,开展非均质致密储层真三轴水力压裂实验和数值模拟研究,分析非均质岩石水平井分段压裂多裂缝扩展规律。结果表明:非均质性强的致密储层在水平井分段压裂时会产生不均一的裂缝形态,低两向水平应力差会强化储层非均质对裂缝形态差异性的影响,压裂液黏度对非均质储层改造时裂缝的形态影响相对较小,高弹性模量区域裂缝扩展相对更充分;数值模拟则证实储层非均质性会增加应力干扰的影响程度,通过改变弹性模量、压裂液排量等压裂参数均可以实现裂缝扩展的起裂扩展调控,因此对于非均质性较强的储层而言,有必要通过限流法或者暂堵等其他工艺手段进行水平井分段压裂施工,其中限流法可以保证不同位置的裂缝可以均衡进液,实现段内裂缝的同步和充分扩展,暂堵压裂则可以实现储层的充分打碎。研究成果有助于指导不同改造思路下的水平井压裂工艺优选。

关键词：致密储层水平井非均质裂缝扩展扩展有限元

Open-source algorithm and software for computed tomography-based virtual pancreatoscopy and other applications

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Visual Computing for Industry,Biomedicine,and Art 2022年第1期5卷 239-249页

作者： Haofan Huang Xiaxia yu Mu Tian Weizhen He Shawn Xiang Li zhengrong Liang Yi Gao School of Biomedical Engineering Health Science CenterShenzhen UniversityShenzhen 518060China Laboratory for Imaging Research and Informatics State University of New YorkStony BrookNY 11794USA Shenzhen Key Laboratory of Precision Medicine for Hematological Malignancies Shenzhen 518060China Marshall Laboratory of Biomedical Engineering Shenzhen 518060China Peng Cheng Laboratory Shenzhen 518066China

Pancreatoscopy plays a significant role in the diagnosis and treatment of pancreatic diseases.However,the risk of pancreatoscopy is remarkably greater than that of other endoscopic procedures,such as gastroscopy and bronchoscopy,owing to its severe invasiveness.In comparison,virtual pancreatoscopy(VP)has shown notable advantages.However,because of the low resolution of current computed tomography(CT)technology and the small diameter of the pancreatic duct,VP has limited clinical use.In this study,an optimal path algorithm and super-resolution technique are investigated for the development of an open-source software platform for VP based on 3D Slicer.The proposed segmentation of the pancreatic duct from the abdominal CT images reached an average Dice coefficient of 0.85 with a standard deviation of 0.04.Owing to the excellent segmentation performance,a fly-through visualization of both the inside and outside of the duct was successfully reconstructed,thereby demonstrating the feasibility of VP.In addition,a quantitative analysis of the wall thickness and topology of the duct provides more insight into pancreatic diseases than a fly-through visualization.The entire VP system developed in this study is available at https://***/gaoyi/VirtualEndoscopy.git.

关键词： Pancreatic cancer Pancreatic duct segmentation Virtual pancreatoscopy 3D Slicer

经内镜逆行性胰胆管造影取石术与传统术式治疗胰管结石的临床疗效比较

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中华胰腺病杂志 2024年第3期24卷 199-204页

作者：欧峥嵘严安彭程朱卫东余枭湖南师范大学附属岳阳医院普外二科岳阳414000 中南大学湘雅三医院肝胆胰外科长沙410013

目的比较经内镜逆行性胰胆管造影(ERCP)取石术与传统术式在胰管结石治疗中的临床疗效。方法回顾性分析2017年11月至2022年11月间湖南师范大学附属岳阳医院和中南大学湘雅三医院住院的47例慢性胰腺炎合并胰管结石患者的临床资料,按结石... 详细信息

目的比较经内镜逆行性胰胆管造影(ERCP)取石术与传统术式在胰管结石治疗中的临床疗效。方法回顾性分析2017年11月至2022年11月间湖南师范大学附属岳阳医院和中南大学湘雅三医院住院的47例慢性胰腺炎合并胰管结石患者的临床资料,按结石手术治疗方式分为ERCP组(19例)、腹腔镜组(10例)和开腹组(18例),比较3组患者的一般临床特征、手术及术后恢复指标、疼痛程度分级、一期结石清除率、并发症发生率及胰腺功能评价等指标。结果3组患者的年龄、性别、体重指数、病因、病程、症状(腹痛、腹泻)、结石部位、结石大小、术前肿瘤标志物(CEA、AFP、CA19-9)及血清炎症因子(CRP)水平差异均无统计学意义。ERCP组手术时间(1.47±0.51)h、术后首次排气时间(1.16±0.20)d、引流管拔除时间(8.68±3.30)d、住院时间(11.37±4.59)d及术中失血量(109.5±16.5)ml、术后第1天CRP(11.24±2.62)mg/L、治疗费用(35238±10663)元均短于或低于腹腔镜组、开腹组;腹腔镜组术后首次排气时间(2.40±0.70)d、引流管拔除时间(12.10±5.36)d及术中失血量(195.0±83.2)ml、术后第1天CRP(14.52±3.62)mg/L及治疗费用(69908±11310)元均短于或低于开腹组,差异均有统计学意义(P值均<0.05)。ERCP组中、重度疼痛者(10.53%)低于腹腔镜组(70.00%)、开腹组(83.38%),差异有统计学意义(P值均<0.05)。ERCP组一期结石清除率及并发症发生率、术后糖化血红蛋白水平与腹腔镜组、开腹组比较差异无统计学意义,但患者体重下降(26.32%)、腹泻发生率(21.05%)较腹腔镜组、开腹组低,差异有统计学意义(P值均<0.05)。结论ERCP取石术是一种有效、安全、微创、经济的治疗胰管结石的方法,适合于多数胰管结石患者,但对于结石嵌顿或复杂胰管结石的患者,应根据实际情况选择腹腔镜或开腹手术治疗。

关键词：胰管结石内镜逆行胰胆管造影术内镜取石术外科手术腹腔镜取石术临床疗效

上呼吸道感染儿童中肠道病毒流行病学特征分析

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中国病毒病杂志 2024年第2期14卷 152-158页

作者：王钰汤晶晶柏桂珍丁峥嵘昆明医科大学云南昆明650500 云南省疾病预防控制中心云南昆明650022 云南省肠道病毒研究中心云南昆明650022

目的了解上呼吸道感染患儿中肠道病毒(enterovirus,EV)流行病学特征,为防控肠道病毒相关呼吸道感染提供依据。方法2021年1月─2022年9月在昆明市儿童医院门诊采集上呼吸道感染患儿咽拭子标本,提取标本RNA,使用实时荧光定量反转录聚合酶... 详细信息

目的了解上呼吸道感染患儿中肠道病毒(enterovirus,EV)流行病学特征,为防控肠道病毒相关呼吸道感染提供依据。方法2021年1月─2022年9月在昆明市儿童医院门诊采集上呼吸道感染患儿咽拭子标本,提取标本RNA,使用实时荧光定量反转录聚合酶链反应(real-time quantitative reverse transcription PCR,real-time qRT-PCR)检测肠道病毒核酸,阳性标本采用半巢式反转录PCR(semi-nested reverse transcription PCR,semi-nested RT-PCR)方法进行VP1编码区扩增、测序和基因定型,用生物信息学软件进行分子流行病学相关分析;采用SPSS20.0统计分析软件进行数据分析。结果1023例患儿中肠道病毒阳性率为46.82%(479/1023),对94例(19.62%,94/479)标本成功扩增并测序,鉴定出17种基因型:60例(63.83%,60/94)鉴定为EV-A种中的7种基因型;33例(35.11%,33/94)鉴定为EV-B种中的10种基因型;1例(1.06%,1/94)为EV-C种的脊髓灰质炎病毒Ⅰ型疫苗株病毒。监测期间除个别月份外,肠道病毒月检出率均≥40.00%。<1岁、1~<6岁、6~<9岁和≥9岁年龄段儿童肠道病毒检出率分别为42.89%(169/394)、48.85%(213/436)、47.17%(75/159)和64.71%(22/34),不同年龄段肠道病毒阳性检出率差异无统计学意义(χ^(2)=7.54,P=0.057)。发热、咳嗽和疱疹为主要临床症状,临床诊断以疱疹性咽峡炎(20/90,22.22%)和感染性发热(19/90,21.11%)为主。系统进化分析结果显示,同型别本地序列、参考株与原型株汇聚在一大分支内,本地序列具有相对较近亲缘关系,与原型株距离较远;同时间段内,同型别本地序列呈现多条传播链共循环;或在不同时空,同一毒株发生了远距离跨区域传播。结论肠道病毒是昆明市本地呼吸道感染的重要病原,由多种型别引起,本地肠道病毒形成了独特的进化分支。

关键词：呼吸道感染肠道病毒测序基因分型流行病学特征

Seasonal change of circulating leptin associated with testicular activities of the wild ground squirrels(Citellus dauricus)

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Integrative Zoology 2023年第1期18卷 76-92页

作者： Wenyang yu Sijie FAN Xi WANG Jueyu ZHU zhengrong yuAN Yingying HAN Haolin ZHANG Qiang WENG Laboratory of Animal Physiology College of Biological Sciences and TechnologyBeijing Forestry UniversityBeijingChina

The purpose of this study was to explore the variations in the circulating leptin concentrations of the wild ground squirrels in relation to seasonal changes in testicular activities.Hematoxylin-eosin staining showed all types of elongated spermatids and spermatogenic cells existed in the testis in April,while the primary spermatocytes and spermatogonia were most advanced stages of germ cells in June.In addition,the primary spermatocytes,secondary spermatocytes,and spermatogonia were most advanced stages of germ cells in September.The highest circulating leptin concentration was consistent with the maximum body weight results from accumulation of adipose tissue in September.The mRNA expression level of leptin receptor(Ob-R)and STAT3 was lowest in June,raised in September,and remained increased in April.Ob-R and STAT3 were stronger staining in the Leydig cells in July.Moreover,the concentrations of testosterone(T)showed the maximum values in April,the minimum values in June,and signiﬁcant increases in September.Furthermore,it is worth noting that the levels of T increased with the mRNA levels of Ob-R,STAT3,StAR,and testicular steroidogenic enzymes(3β-HSD,P450c17,and P450scc).Moreover,RNA-seq analyses of testis during the different periods showed that a total of 4209 genes were differ-entially expressed genes(DEGs);further analysis revealed that DEGs related with the Jak/STAT pathways and reproduction were altered.Taken together,the results suggested that the leptin regulated testicular function through the Jak/STAT pathways and testicular steroidogenic factor expressions.

关键词： leptin Ob-R STAT3 steroidogenic enzyme testis wild ground squirrel

Case Analysis of a Pump-Driven Heat Pipe Heat Recovery Ventilator in an Existing Experiment Building

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Energy Engineering 2022年第4期119卷 1393-1402页

作者： Zhun Li zhengrong Ouyang Tianbao Sun Qiang Li Xiaobo Zhao Rong yu Hefei Institutes of Physical Science Chinese Academy of SciencesHefei230031China University of Science and Technology of China Hefei230026China National Institute of Metrology Beijing100029China

The building energy consumption is an important part among the total society energy consumption,in which the energy consumption for air conditioning occupies almost 70%.The energy consumption of the air conditioning system for fresh air handling can be saved effectively when the exhaust air energy could be recovered to preheat or precool the fresh air.Considering the install locations requirements on field,the pump-driven heat pipes(PHP)were developed as heat recovery ventilators(HRVs)and used in an existing experiment building in Beijing Urban.The thermal performance of the PHP HRVs was tested in real operation time periods under winter running mode.Both the power and heat consumption of the modular air handling units with and without HRVs were monitored and obtained,as well as the hourly power and heat consumption.The energy savings of HRVs were analyzed.The results indicate that the PHP HRVs can work steadily and meet the energy recovery need well.The temperature effectiveness of the HRVs can be kept from 60%to 70%.The test total energy saving rate was 24.48%,and the average hourly heat consumption reduced by 28.54%.The daily energy consumption can be saved by 118 kWh,and the energy savings can reach to 9440 kWh for a whole winter.

关键词： Case analysis heat recovery ventilator pump-driven heat pipe temperature effectiveness energy saving