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健康婴幼儿及儿童QRS波的比较研究

临床儿科杂志 2009年第1期27卷 51-57,83页

作者：周弋李奋孙锟 Sophia Zhou 李筠杨健萍朱敏邢海华上海市浦东新区疾病预防控制中心上海200136 上海交通大学医学院附属上海儿童医学中心心血管内科上海200127 Agilent Technoligies Andover MA USA 01810

目的比较研究不同年龄和性别健康婴幼儿及儿童心电图QRS波群各波振幅特点及其与疾病诊断有关的一些参数,以评估现有国内外标准应用于当今我国儿童的可行性。方法记录上海地区1557名健康婴幼儿和儿童(男812例,女745例,1～17岁)Q波电压、... 详细信息

目的比较研究不同年龄和性别健康婴幼儿及儿童心电图QRS波群各波振幅特点及其与疾病诊断有关的一些参数,以评估现有国内外标准应用于当今我国儿童的可行性。方法记录上海地区1557名健康婴幼儿和儿童(男812例,女745例,1～17岁)Q波电压、Q/R值、R波振幅、S波振幅、RV1+SV5、Sokolow指数、QRS波总振幅及R/S比值,并用专用软件进行统计分析。结果QRS波各波振幅存在明显的年龄差异。Q波振幅的正常上限较湖南标准大,与国外标准比较也有差异。胸前导联R波、S波振幅与既往标准比较有差异。胸前导联QRS波振幅的性别差异较肢导联明显,12岁后的年长儿童中,男性和女性差异有统计学意义,且几乎都是男性大于女性。结论正常婴幼儿及儿童QRS波群各波振幅具有明显的年龄、性别、时间和种族差异。沿用传统的国内外正常婴幼儿及儿童心电图标准不合适,有必要进一步修订更新传统的正常值标准,并应重视年龄、性别间的差异。此外,与此相关的疾病的诊断标准也应修订。

关键词：婴幼儿及儿童心电图 QRS波正常值

Leaf and root phenology and biomass of Eriophorum vaginatum in response to warming in the Arctic

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Journal of Plant Ecology 2022年第5期15卷 1091-1105页

作者： Ting ma Thomas Parker Ned Fetcher Steven L.Ungers Jon Gewirtzman Michael L.Moody Jianwu Tang The Ecosystems Center Marine Biological LaboratoryWoods HoleMA 02543USA College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China Department of Biological and Environmental Sciences Faculty of Natural SciencesUniversity of StirlingStirlingUK Institute for Environmental Science and Sustainability Wilkes UniversityWilkes-BarrePA 18766USA Department of Biological Sciences Florida International UniversityMiamiFL 33199USA Yale School of the Environment New HavenCT 06520USA Department of Biological Sciences University of Texas at El PasoEl PasoTX 79968USA

The response of plant leaf and root phenology and biomass in the Arctic to global change remains unclear due to the lack of synchronous measurements of above-and belowground *** objective was to determine the phenological dynamics of the above-and belowground parts of Eriophorum vaginatum in the Arctic and its response to *** established a common garden located at Toolik Lake Field Station;tussocks of *** from three locations,Coldfoot,Toolik Lake and Sagwon,were transplanted into the common *** and warming treatments for *** were set up at the Toolik Lake during the growing seasons of 2016 and *** cameras,a handheld sensor and minirhizotrons were used to simultaneously observe leaf greenness,normalized difference vegetation index and root length dynamics,*** and root growth rates of *** were asynchronous such that the timing of maximal leaf growth(mid-july)was about 28 days earlier than that of root *** of air temperature by 1°C delayed the timing of leaf senescence and thus prolonged the growing season,but the temperature increase had no significant effect on root *** seasonal dynamics of leaf biomass were affected by air temperature,whereas root biomass was correlated with soil thaw ***,we suggest that leaf and root components should be considered comprehensively when using carbon and nutrient cycle models,as above-and belowground productivity and functional traits may have a different response to climate warming.

关键词： Eriophorum vaginatum phenology warming aboveground biomass belowground biomass

四大洲食用昼花属的比较入侵生态学:对养分和竞争的响应

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Journal of Plant Ecology 2023年第1期16卷 135-149页

作者： Rubén Portela Rodolfo Barreiro Peter Alpert Cheng-Yuan Xu Bruce L.Webber Sergio R.Roiloa BioCost Group Department of BiologyFaculty of ScienceUniversidade da Coruña15071A CoruñaSpain Biology Department University of MassachusettsAmherstMA 01003USA Jepson and University Herbaria University of CaliforniaBerkeleyCA 94709USA School of Health Medical and Applied SciencesCentral Queensland UniversityBundabergQLD 4670Australia CSIRO Health and Biosecurity FloreatWestern Australia 6016Australia School of Biological Sciences The University of Western AustraliaCrawleyWestern Australia 6009Australia Western Australian Biodiversity Science Institute PerthWestern Australia 6000Australia

入侵生物学的两个关键假设是,某些特征是外来物种入侵的基础,且这些特征是在引入期间或之后选择的。我们通过关注两个可能赋予入侵性的特征来检验这些假设,即营养增加引起的较高生长加速和竞争引起的较低生长减速。我们对采自非洲、澳... 详细信息

入侵生物学的两个关键假设是,某些特征是外来物种入侵的基础,且这些特征是在引入期间或之后选择的。我们通过关注两个可能赋予入侵性的特征来检验这些假设,即营养增加引起的较高生长加速和竞争引起的较低生长减速。我们对采自非洲、澳洲、欧洲和北美洲的4个食用昼花属(Carpobrotus)品种进行了比较。为了测试高入侵物种莫邪菊(Carpobrotus edulis)对这些特征的选择,我们将原产于南非的植株与入侵其他3个地区的植株进行了比较。在一个同质园中繁殖植株。然后,在添加或不添加养分的情况下单独培育子代,并在不添加养分的情况下将子代与另一个食用昼花属品种一起、或与欧洲的一种共生本土物种马兰草(Ammophila arenaria)一起培育。不同品种的食用昼花属对营养物质的反应并无差异,在入侵性更强的物种中,竞争反应的负面性也没有减弱。然而,与本土莫邪菊相比,添加营养物质引起外来莫邪菊更高的生长加速。此外,在处理开始时,两种入侵物种每分株的鲜质量高于两种非入侵物种。我们的研究结果表明,引种可以选择入侵物种对营养富集的反应进行选择,也证明了外来植物的体积和入侵性之间的关联。

关键词：食用昼花属海岸沙丘竞争反应外来入侵植物养分有效性快速进化

Sci Rep:科学家阐明线粒体的程序性细胞死亡过程

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现代生物医学进展 2016年第35期16卷 I0004-I0004页

作者： Ted D. Pham Phi Q. Pham Jinfeng Li Anthony G. Letai Douglas C. Wallace Peter J. Burke Department of Biomedical Engineering University of California Irvine CA USA Department of Chemical Engineering and materials Science University of California Irvine CA USA Department of Chemical Engineering and materials Science University of California Irvine CA USA Dana-Farber Cancer Institute Harvard University Boston MA USA Center for Mitochondrial and Epigenomic Medicine Children’s Hospital of Philadelphia and Department of Pathology and Laboratory Medicine University of Pennsylvania Philadelphia PA USA Department of Biomedical Engineering University of California Irvine CA USA Department of Chemical Engineering and materials Science University of California Irvine CA USA Department of Electrical Engineering and Computer Science University of California Irvine CA USA

日前。发表在Scientific Reports杂志上的一篇研究报告中，来自加利福尼亚大学等机构的研究人员通过利用一种由石墨烯组成的新型传感器深入解析了线粒体的程序性细胞死亡过程，该研究或为驱动癌细胞自我毁灭提供了新的线索。研究者通过... 详细信息

日前。发表在Scientific Reports杂志上的一篇研究报告中，来自加利福尼亚大学等机构的研究人员通过利用一种由石墨烯组成的新型传感器深入解析了线粒体的程序性细胞死亡过程，该研究或为驱动癌细胞自我毁灭提供了新的线索。研究者通过研究开发了一种监测线粒体改变的电子学方法，该方法能够指示出细胞进行自我毁灭的开始阶段，我们机体每个细胞中都有数百个、甚至数千个线粒体。每个线粒体都有着内膜和外膜结构；作为细胞的能量工厂，线粒体会对细胞中的碳水化合物和脂肪进行代谢产能以便细胞利用并且储存。但同时线粒体还有第二个角色，那就是调节细胞的生死通路。

关键词：死亡过程癌细胞线粒体程序性 Sci 科学家 Rep 加利福尼亚大学

Oxygen sufficiency controls TOP mRNA translation via the TSC-Rheb-mTOR pathway in a 4E-BP-independent manner

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Journal of Molecular Cell Biology 2014年第3期8卷 255-266页

作者： Rachel Miloslavski Elad Cohen Adam Avraham Yifat I luz Zvi Hayouka Judith Kasir Rajini Mudhasani Stephen N. Jones Nadine Cybulski markus A. Ruegg Ola Larsson Valentina Gandin Arjuna Rajakumar Ivan Topisirovic Oded Meyuhas Department of Biochemistry and Molecular Biology The Institute for Medical Research - Israel-Canada The Hebrew University-Hadassah Medical School Jerusalem 91120 Israel Department of Cell Biology University of Massachusetts Medical School North Worcester MA 01655 USA Biozentrum University of Basel Klingelbergstrasse 70 CH-4056 Basel Switzerland Department of Oncolo'gy-Pathology Karolinska Instituie Stockholm SE-171 76 Sweden Lady Davis Institute for Medical Research Sir Mortimer B. Davis-Jewish General Hospital and Department of Oncology McGill University Montreal QC H3T 1E2 Canada Present address: Migal-Galilee Research Institute Kiryat Shmona 11016 Israel Present address: United States Army Medical Research Institute of Infectious Diseases Frederick MD 21702-5011 USA Present address: ADAM Montreal QC H3N 2C7 Canada

Cells encountering hypoxic stress conserve resources and energy by downregulating the protein synthesis. Here we demonstrate that one mechanism in this response is the translational repression of TOP mRNAs that encode components of the translational apparatus. This mode of regulation involves TSC and Rheb, as knockout of TSC1 or TSC2 or overexpression of Rheb rescued TOP mRNA translation in oxygen-deprived celts. Stress-induced translational repression of these mRNAs closely correlates with the hypophosphorylated state of 4E-BP, a translational repressor. However, a series of 4E-BP loss- and gain-of-function experiments disprove a cause-and- effect relationship between the phosphorylation status of 4E-BP and the translational repression of TOP mRNAs under oxygen or growth factor deprivation. Furthermore, the repressive effect of anoxia is similar to that attained by the very efficient inhibition of mTOR activity by Torin 1, but much more pronounced than roptor or rictor knockouL Likewise, deficiency of raptor or rictor, even though it mildly downregulated basal translation efficiency of TOP mRNAs, failed to suppress the oxygen-mediated translational activation of TOP mRNAs. Finally, co-knockdown of TIA-1 and TIAR, two RNA-binding proteins previously implicated in translational repression of TOP mRNAs in amino acid-starved cells, failed to relieve TOP mRNA translation under other stress conditions. Thus, the nature of the proximal translational regulator of TOP m RNAs remains elusive.

关键词： hypoxia roTOR TOP mRNAs translational control 4E-BP

Projection micro stereolithography based 3D printing and its applications

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International Journal of Extreme manufacturing 2020年第2期2卷 68-86页

作者： Qi Ge Zhiqin Li Zhaolong Wang Kavin Kowsari Wang Zhang Xiangnan He Jianlin Zhou Nicholas X Fang Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongPeople’s Republic of China BMF material Technology Inc. Shenzhen 518110ShenzhenPeople’s Republic of China State-Key Laboratory of Advanced Design and manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082HunanPeople’s Republic of China Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139-4307United States of America Digital manufacturing and Design Centre Singapore University of Technology and Design487372Singapore

Projection micro stereolithography(PμSL)is a high-resolution(up to 0.6μm)3D printing technology based on area projection triggered photopolymerization,and capable of fabricating complex 3D architectures covering multiple scales and with multiple *** paper reviews the recent development of the PμSL based 3D printing technologies,together with the related *** introduces the working principle,the commercialized products,and the recent multiscale,multimaterial printing capability of PμSL as well as some functional photopolymers that are suitable to Pμ*** review paper also summarizes a few typical applications of PμSL including mechanical metamaterials,optical components,4D printing,bioinspired materials and biomedical applications,and offers perspectives on the directions of the further development of PμSL based 3D printing technology.

关键词： projection microstereolithography multiscale 3D printing multimaterial 3D printing

Human mobility data in the COVID-19 pandemic:characteristics,applications,and challenges

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International Journal of Digital Earth 2021年第9期14卷 1126-1147页

作者： Tao Hu Siqin Wang Bing She Mengxi Zhang Xiao Huang Yunhe Cui Jacob Khuri Yaxin Hu Xiaokang Fu Xiaoyue Wang Peixiao Wang Xinyan Zhu Shuming Bao Wendy Guan Zhenlong Li Department of Geography Oklahoma State UniversityStillwaterOKUSA Center for Geographic Analysis Harvard UniversityCambridgeMAUSA School of Earth and Environmental Sciences The University of QueenslandSt LuciaAustralia Institute for Social Research University of MichiganAnn ArborMIUSA School of Health Ball State UniversityMuncieINUSA Department of Geosciences University of ArkansasFayettevilleARUSA Department of Geography University of ConnecticutStorrsCTUSA Lake Erie College of Osteopathic Medicine Seton Hill UniversityGreensburgPAUSA School of Resource and Environmental Sciences Wuhan UniversityWuhanPeople’s Republic of China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanPeople’s Republic of China China Data Institute Ann ArborMIUSA Geoinformation and Big Data Research Laboratory Department of GeographyUniversity of South CarolinaColumbiaSCUSA

The COVID-19 pandemic poses unprecedented challenges around the *** studies have applied mobility data to explore spatiotemporal trends over time,investigate associations with other variables,and predict or simulate the spread of *** objective was to provide a comprehensive overview of human mobility open data to guide researchers and policymakers in conducting data-driven evaluations and decision-making for the COVID-19 pandemic and other infectious disease *** summarized the mobility data usage in COVID-19 studies by reviewing recent publications on COVID-19 and human mobility from a data-oriented *** identified three major sources of mobility data:public transit systems,mobile operators,and mobile phone *** approaches have been commonly used to estimate human mobility:public transit-based flow,social activity patterns,index-based mobility data,and social media-derived mobility *** compared mobility datasets’characteristics by assessing data privacy,quality,space–time coverage,high-performance data storage and processing,and *** also present challenges and future directions of using mobility *** review makes a pivotal contribution to understanding the use of and access to human mobility data in the COVID-19 pandemic and future disease outbreaks.

关键词： COVID-19 public health human mobility open data mobile phone mobility index

New possible silver lining for pancreatic cancer therapy:Hydrogen sulfide and its donors

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Acta Pharmaceutica Sinica B 2021年第5期11卷 1148-1157页

作者： Xu Hua Yan Xiao Jianan Sun Bao Ji Shanshan Luo Bo Wu Chao Zheng Peng Wang Fanxing Xu Keguang Cheng Huiming Hua Dahong Li Key Laboratory of Structure-Based Drug Design&Discovery Ministry of EducationSchool of Traditional Chinese Materia MedicaShenyang Pharmaceutical UniversityShenyang 110016China School of Pharmaceutical Engineering Shenyang Pharmaceutical UniversityShenyang 110016China Key Laboratory of Cardiovascular and Cerebrovascular Medicine Nanjing Medical UniversityNanjing 211166China Molecular Imaging Laboratory MGH/MIT/HMS Athinoula A.Martinos Center for Biomedical ImagingDepartment of RadiologyMassachusetts General Hospital/Harvard Medical SchoolCharlestownMA 02129USA PET Center Department of Radiology and Biomedical ImagingYale University School of MedicineNew HavenCT 06520USA Department of Biomedical Engineering School of EngineeringChina Pharmaceutical UniversityNanjing 210009China Wuya College of Innovation Shenyang Pharmaceutical UniversityShenyang 110016China State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and PharmacyGuangxi Normal UniversityGuilin 541004China

As one of the most lethal diseases,pancreatic cancer shows a dismal overall prognosis and high resistance to most treatment ***,pancreatic cancer escapes early detection during the curable period because early symptoms rarely emerge and specific markers for this disease have not been *** combinations of new drugs,multimodal therapies,and adjuvants prolong survival,most patients still relapse after surgery and eventually ***,the search for more effective treatments for pancreatic cancer is highly relevant and *** a newly re-discovered mediator of gasotransmission,hydrogen sulfide(H2S)undertakes essential functions,encompassing various signaling complexes that occupy key processes in human *** evidence indicates that H2S exhibits bimodal modulation of cancer ***,endogenous or low levels of exogenous H2S are thought to promote cancer,whereas high doses of exogenous H2S suppress tumor ***,inhibition of endogenous H2S production also suppresses tumor ***,H2S biosynthesis inhibitors and H2S supplementation(H2S donors)are two distinct strategies for the treatment of ***,modulation of endogenous H2S on pancreatic cancer has not been studied so ***,H2S donors and their derivatives have been extensively studied as potential therapeutic agents for pancreatic cancer therapy by inhibiting cell proliferation,inducing apoptosis,arresting cell cycle,and suppressing invasion and migration through exploiting multiple signaling *** far as we know,there is no review of the effects of H2S donors on pancreatic *** on these concerns,the therapeutic effects of some H2S donors and NO-H2S dual donors on pancreatic cancer were summarized in this *** H2S donors may be promising compounds for pancreatic cancer treatment.

关键词： Pancreatic cancer Hydrogen sulfide donor Sulfur-containing compound Cell proliferation Antitumor effect Signaling pathway

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生成性:一个数字化创新的基石性概念评述

外国经济与管理 2024年第7期46卷 3-21页

作者：邹波李淑华孙黎刘昶中山大学管理学院广东广州510006 中山大学商学院广东深圳518107 洛厄尔麻省大学曼宁商学院美国洛厄尔MA01854 曼彻斯特大学商学院英国曼彻斯特M156PB

数字经济时代下,跨学科研究正在将“生成性”发展成数字化创新领域的基石性概念。现有研究围绕生成性的研究议题众多,但整体研究框架尚不清晰,核心议题也不明确。本文以122篇数字化创新领域生成性的英文文献为研究对象,基于LDA主题模型... 详细信息

数字经济时代下,跨学科研究正在将“生成性”发展成数字化创新领域的基石性概念。现有研究围绕生成性的研究议题众多,但整体研究框架尚不清晰,核心议题也不明确。本文以122篇数字化创新领域生成性的英文文献为研究对象,基于LDA主题模型聚合出20个主题,结合人工编码确定了内涵、前因、作用机制和产出结果4个核心研究内容,对此展开研究:(1)对不同学科和视角下生成性的内涵进行了梳理,提炼出数字化创新领域生成性概念的共性内涵;(2)从技术因素和社会因素两个方面梳理生成性的前因,对生成性的形成机理进行系统归纳;(3)基于“元亨利贞”分析框架阐释生成性对数字化创新的作用机制和产出结果,揭示生成性促进数字化创新的底层逻辑。同时,围绕生成性的内涵、前因、作用机制和产出结果,提出未来研究方向。本文对数字化创新领域的生成性文献进行了系统性归纳,并指出未来研究方向,能够为本领域的进一步研究提供文献基础和研究思路。

关键词：生成性数字化创新基石性概念评述元亨利贞