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6313篇 您的检索式:作者名="HofmannE"
    题名 作者 年代 出处 被引量
1城市化水平的决定因素:跨国回归模型及分析显示文摘全球正在经历历史上最大规模的城市化进程,识别影响城市化水平的关键因素,对于各国制定科学的城市化战略无疑具有重大意义。本文利用联合国WUP数据库和最新WDI数据库,以全世界229个国家1950—2010年间城市化与经济增长等相关数据为基础,采用工具变量法对决定城市化水平的主要因素展开实证分析。研究发现,经济增长、非农化(第二、三产业GDP比重)和人力资本水平(成年人平均受教育年限)是决定城市化进程的关键因素。经济增长每提高1个百分点,人口受教育年限每增加1年,工业化率每提高1个百分点,城市化率分别增加0.9、2.0和0.4个百分点。作为一个尝试,利用该跨国模型,本文估计了中国2010年'基于国际经验'的城市化率,从这个角度看中国的城市化的确可能存在滞后的问题。万广华 郑思齐 Anett Hofmann 2014世界经济文汇2014,,4:13
2CD44v对大鼠多形胶质瘤细胞系RG2的转移促进作用显示文摘研究颅外生长的胶质母细胞瘤能否转移以及CD44v对它们转移能力的影响。利用基因转染技术,将自发表达CD44v(meta-1)的载体导入转移力较低的大鼠胶质瘤RG2细胞内,并对有或无CD44v表达的RG2细胞做系统的实验性转移观察。结果发现,与无CD44v表达的母系RG2细胞(RG2-m)相比,CD44v的转染子RG2-a的生长指标和形态学特点并无明显改变;但RG2-a在荷瘤大鼠体内转移出现的时间明显提前,在单位时间内,受累器官的数量增加和破坏程度更为严重。研究结果证实:颅外生长的胶质母细胞具有自发转移能力,CD44v可明显提高RG2细胞的转移效率。李宏 Martin Hofmann 刘佳 江岩 郭丽 罗阳 鲁海欧 1996中华肿瘤杂志1996,18,5:12
3Transforming growth factor-β1 induces intestinal myofibroblast differentiation and modulates their migration显示文摘AIM:To investigate the effects of transforming growth factorβ1(TGF-β1)on the differentiation of colonic lamina propria fibroblasts(CLPF)into myofibroblasts in vitro. METHODS:Primary CLPF cultures were incubated with TGF-β1 and analyzed for production ofα-smooth muscle actin(α-SMA),fibronectin(FN)and FN isoforms.Migration assays were performed in a modified 48-well Boyden chamber.Levels of total and phosphorylated focal adhesion kinase(FAK)in CLPF were analyzed after induction of migration.RESULTS:Incubation of CLPF with TGF-β1 for 2 d did not changeα-SMA levels,while TGF-β1 treatment for 6 d significantly increasedα-SMA production. Short term incubation(6 h)with TGF-β1 enhanced CLPF migration,while long term treatment(6 d)of CLPF with TGF-β1 reduced migration to 15%-37% compared to untreated cells.FN and FN isoform mRNA expression were increased after short term incubation with TGF-β1(2 d)in contrast to long term incubation with TGF-β1 for 6 d.After induction of migration, TGF-β1-preincubated CLPF showed higher amounts of FN and its isoforms and lower levels of total and phosphorylated FAK than untreated cells. CONCLUSION:Long term incubation of CLPF with TGF-β1 induced differentiation into myofibroblasts with enhancedα-SMA,reduced migratory potential and FAK phosphorylation,and increased FN production.In contrast,short term contact(6 h)of fibroblasts with TGF-β1 induced a dose-dependent increase of cell migration and FAK phosphorylation without induction ofα-SMA production.Julia Brenmoehl Sandra Nicole Miller Claudia Hofmann Daniela Vogl Werner Falk Jrgen Schlmerich Gerhard Rogler 2009World Journal of Gastroenterology2009,15,12:12
4干旱胁迫下5种三叶草的生理反应(英文)显示文摘为了解三叶草属抗旱的生理机理,寻找适宜干旱地区种植的三叶草品种,比较了地三叶草(Trifoliumsubterraneum L.)、大花三叶草(rmichelianum Savi)、自:二三叶草(rrepens L.)、高加索三叶草(T.ambiguum M.Bieb.)和草莓三叶草(zfragiferum L.)在人工干旱条件下4wk的生长和生理反应.结果表明,干旱处理下大仡乏叶草、草莓三叶草和白三叶草地上部分干重严重减少,分别降低了70%、66%和64%,而高加索三叶草和地三叶草减少不到50%;高加索三叶草叶片水势降低到-2.0MPa以下,而其他4种三叶草只降低到-1.5MPa左右;高加索三叶草和争莓三叶草叶片光合速率降低25%,而地三叶草、白三叶草和大花三叶草下降35%~63%.此外,干旱条件下,5种供试三叶草叶片中游离脯氨酸含量普遍增加,其中高加索三叶草和白三叶草分别增加到2.5倍和3.1倍.研究显示高加索三叶草在多项重要生长和生理指标中表现出很强的抗旱性,因此认为其可作为干旱地区栽培自叶草的补充或替代种.蔺万煌 HOFMANN Rainer W STILWELL Stephen A 2011应用与环境生物学报2011,17,4:7
5肉和肉制品的质量概念显示文摘肉的质量的重要性在增加 当前,肉的质量、质量肉、名牌肉、胴体质量和质量保证等问题引起了科研部门、肉生产、加工部门和市场方面的很大兴趣。由于高度发达国家的农业上已能生产充裕的食品,我们已不再仅仅关心保证足够的肉和肉制品的数量供应,倒是担心在以后的较长时期里如何改善市场的销售机会了。Klaus Hofmann 张孝若 1994肉类工业1994,,3:6
6非破坏性产量测定方法在放牧草地产量动态研究中的应用显示文摘草地牧草的产量是植被高度和(或)密度函数。一种特殊的圆盘测量工具所测定的草地植被压缩高度,可以同时反映植被高度和植被密度,即草地植被压缩高度成为草地植被自然高度和密度的函数,这样草地牧草的现存量就可能成为植被压缩高度的函数。试验采用这种圆盘测定工具在轻度放牧和强度放牧两种放牧强度下对草地牧草的现存量及植被特征进行了观测。试验结果表明,在不同放牧强度下,牧草压缩高度与牧草产量具有良好的回归关系,决定系数r2的波动范围为0.82~0.95;每1cm的牧草压缩高度相当于100~250kg/hm2/cm的牧草现存量,强度放牧草地中,该数值一般高于轻度放牧草地;不同测定日期对压缩高度与牧草产量的回归关系影响很大。在大约两星期的测定间隔时,相邻测定日期所得到的回归系数大多具有明显差异(P<0.05)。赵钢 MARTINA HOFMANN J.ISSELSTEIN 2004中国草地2004,26,5:5
7全新世大暖期时中国夏季风向西北大幅度漂移的一个古生物地层学证据显示文摘巴丹吉林沙漠东南部边缘巴丹海子全新世大暖期6-9kaBP的湖相沉积中含有大量腹足类化石——Radix cucunorica (Moellendorff), Succinea erythrophana Ancey, Gyraulus sibricus (Dunker), Radix lagotis (Schranck), Gyraulus albus(Miiller), Lymnaea stagnalis(Linnaeus),Gyraulus convexiusculus (HuRon),除Succinea erythrophana Ancey属陆生蜗牛外,余皆为淡水腹足类。这些化石代表了当时温暖湿润的气候环境。其中,现生的Gyraulus convexiusculus (Hutton)生活的最NW位置为地处暖温带的南泥湾,据此推知,6-9kaBP时的巴丹海子的气温和降水至少较今分别高出1.1℃和440mnl;从南泥湾至巴丹海子,气候带向NW移动了差不多700km;那时夏季风暖锋位置可向NW移动到从玉门其以NE走向至额济纳旗及其以北的中蒙国界一线,夏季风的波及范围可以漂越甘新交界的深居内陆的星星峡。李保生 HOFMANN Jürgen 陈德牛 温小浩 闫满存 ZHANG David Dian 牛东风 李志文 邱世藩 王丰年 杜恕环 2010地球环境学报2010,1,2:5
8Hybrid multi-chip assembly of optical communication engines by in situ 3D nanolithography显示文摘Three-dimensional(3D)nano-printing of freeform optical waveguides,also referred to as photonic wire bonding,allows for efficient coupling between photonic chips and can greatly simplify optical system assembly.As a key advantage,the shape and the trajectory of photonic wire bonds can be adapted to the mode-field profiles and the positions of the chips,thereby offering an attractive alternative to conventional optical assembly techniques that rely on technically complex and costly high-precision alignment.However,while the fundamental advantages of the photonic wire bonding concept have been shown in proof-of-concept experiments,it has so far been unclear whether the technique can also be leveraged for practically relevant use cases with stringent reproducibility and reliability requirements.In this paper,we demonstrate optical communication engines that rely on photonic wire bonding for connecting arrays of silicon photonic modulators to InP lasers and single-mode fibres.In a first experiment,we show an eight-channel transmitter offering an aggregate line rate of 448 Gbit/s by low-complexity intensity modulation.A second experiment is dedicated to a four-channel coherent transmitter,operating at a net data rate of 732.7 Gbit/s-a record for coherent silicon photonic transmitters with co-packaged lasers.Using dedicated test chips,we further demonstrate automated mass production of photonic wire bonds with insertion losses of(0.7±0.15)dB,and we show their resilience in environmental-stability tests and at high optical power.These results might form the basis for simplified assembly of advanced photonic multi-chip systems that combine the distinct advantages of different integration platforms.Matthias Blaicher Muhammad Rodlin Billah Juned Kemal Tobias Hoose Pablo Marin-Palomo Andreas Hofmann Yasar Kutuvantavida Clemens Kieninger Philipp-Immanuel Dietrich Matthias Lauermann Stefan Wolf Ute Troppenz Martin Moehrle Florian Merget Sebastian Skacel Jeremy Witzens Sebastian Randel Wolfgang Freude Christian Koos 2020Light(Science & Applications)2020,9,1:4
9Review of accelerator driven heavy ion nuclear fusion显示文摘Using high energy accelerators for energy production by nuclear fission goes back to the 1950's with plans for“breeder accelerators”as well as with early ideas on subcritical reactors,which are currently pursued in China and other countries.Also,fusion came in,when the idea emerged in the mid 1970's to use accelerators and their highly time and space compressed beams in order to generate the extremely high density and temperatures required for inertial fusion energy production.Due to the higher repetition rates and efficiencies of accelerators,this was seen as a promising alternative to using high power lasers.After an introduction to nuclear fission applications of accelerators,this review summarizes some of the scientific developments directed towards this challenging application e with focus on the European HIDIF-study-and outlines parameters of future high energy density experiments after construction of the FAIR/Germany and HIAF/China heavy ion accelerator projects.Ingo Hofmann 2018Matter and Radiation at Extremes2018,3,1:4
10草原田鼠和草甸田鼠波动种群雌鼠的攻击性(英文)显示文摘本文比较研究了草原田鼠和草甸田鼠自然种群在不同密度周期时相雌鼠攻击水平的变化。结果表明,不同密度时相,草原田鼠种群中攻击雌鼠所占比例以及接近、威胁、进攻、退避,进攻/接近等5种行为变量均无显著的差异,5种行为变量与种群密度亦均不呈显著的线形相关关系。然而,草甸田鼠在不同密度时相攻击雌鼠的比例差异显著。低密度时相,雌鼠发生威胁行为的平均次数显著高于上升和衰减时相,进攻行为的平均次数亦显著高于其它时相。本研究结果不支持有关田鼠种群在一个完整的周期过程中具有多态性行为的假设。Joyce E. Hofmann Lowell L. Getz 2004兽类学报2004,24,2:4
11促进实施患者血液管理的专家倡议显示文摘贫血、失血以及凝血障碍每年影响数十亿人,均是患者不良结局(死亡率和发病率等)的独立风险因素。患者血液管理是一种全新的医疗模式,可显著减轻或避免此类风险。本研究基于患者血液管理的多重获益和我国相关政策背景发起专家倡议,以促进医疗机构有效实施患者血液管理。专家们一致认为患者血液管理需要卫生健康主管部门的政策推动,相关教育培训和科学研究的促进,医疗机构全员的积极参与,并辅以创新的诊疗路径、合理的医保支付报销方案以及基于数据的评价手段等。张宗久 胡豫 Axel Hofmann 刘远立 纪宏文 2022中国卫生质量管理2022,29,9:4
12Combining Lithoclast and ultrasound power in one device for percutaneous nephrolithotomy: in vitro results of a novel and highly effective technology显示文摘Peter Olbert Jost Weber Axel Hegele Zoltan Varga Axel Heidenreich Rainer Hofmann 2003Urology2003,,1:4
13Free-standing ZnO nanorod arrays modified with single-walled carbon nanotubes for betavoltaics and photovoltaics显示文摘A full-duplex radiant energy converter based on both betavoltaic and photovoltaic effects in an easyto-implement way is an attractive alternative for the autonomous wireless sensor microsystem.Here,we report a novel beta/photovoltaic cell based on free-standing Zn O nanorod arrays(ZNRAs)modified with metallic single-walled carbon nanotubes(m-SWCNTs),using radioisotope63 Ni as beta-emitting source.The ZNRAs were grown on Al-doped Zn O(AZO)conductive glass using hydrothermal method.The optimum length and diameter of Zn O nanorods were determined by Monte Carlo simulation for beta energy deposition in ZNRAs.The m-SWCNTs were anchored into the ZNRAs to form a three-dimensional(3-D)Schottky junction structure for effectively separating the beta/photo-excited electron-hole pairs.Experimentally,the betavoltaic and photovoltaic effects were confirmed through the I-V measurements of beta/photovoltaic cells under beta/UV/Vis irradiations,respectively.It is suggested that the m-SWCNTs play key role for the enhancement of beta/photovoltaic performance through the formation of extensive3-D Schottky junction,the conductive network for hole transport,and the surface plasmon resonance exciton absorption for visible light.Changsong Chen Jiang Chen Zhen Wang Jian Zhang Haisheng San Shichao Liu Chunyu Wu Werner Hofmann 2020Journal of Materials Science & Technology2020,54,19:3
14Stable single-mode operation of 894.6 nm VCSEL at high temperatures for Cs atomic sensing显示文摘In this paper, stable single-mode operation at high temperatures is produced by the surface-relief-integrated vertical cavity surface emitting laser(VCSEL). The gain-cavity mode detuning technique is employed to realize high operating temperatures for the VCSEL. The surface relief is etched in the centre of the top side as a mode discriminator for the fundamental mode output, and the threshold current minimum is 1.94 mA at high temperatures by the gain-cavity mode detuning technique. Maximum single-fundamental-mode output power of 0.45 mW at 80℃ is obtained, and the side mode suppression ratios(SMSRs) are more than 30 dB with increasing temperature and current, respectively.向磊 张星 张建伟 宁永强 Werner Hofmann 王立军 2017Chinese Physics B2017,26,7:3
15心理创伤的心身过程显示文摘本文介绍了精神创伤和创伤后应激障碍(PTSD)的定义、生理心理机制和诊断标准,讨论了与创伤记忆和创伤模式有关的理论和应用问题。Arne Hofmann 盛晓春 2011西华大学学报(哲学社会科学版)2011,30,3:3
16An overview of the logic and rationale of hierarchical linear models显示文摘David A. Hofmann 1997Journal of Management1997,,6:3
17EMDR治疗的初期——基础、诊断与治疗计划(上)显示文摘本文介绍了精神创伤的EMDR(眼动脱敏与再加工)治疗过程中的八个步骤,以及每个步骤中值得注意的问题。Arne Hofmann 盛晓春 2011西华大学学报(哲学社会科学版)2011,30,5:3
18Quality Improvement Guidelines for the Treatment of Lower Extremity Deep Vein Thrombosis with Use of Endovascular Thrombus Removal显示文摘Suresh Vedantham Patricia E. Thorpe John F. Cardella Clement J. Grassi Nilesh H. Patel Hector Ferral Lawrence V. Hofmann Bertrand M. Janne d’Othée Vittorio P. Antonaci Elias N. Brountzos Daniel B. Brown Louis G. Martin Alan H. Matsumoto Steven G. Meranze 2006Journal of Vascular and Interventional Radiology2006,,3:3
19The onset of deep recycling of supracrustal materials at the Paleo-Mesoarchean boundary显示文摘The recycling of supracrustal materials, and in particular hydrated rocks, has a profound impact on mantle composition and thus on the formation of continental crust, because water modifies the physical properties of lithological systems and the mechanisms of partial melting and fractional fractionation. On the modern Earth, plate tectonics offers an efficient mechanism for mass transport from the Earth’s surface to its interior, but how far this mechanism dates back in the Earth’s history is still uncertain. Here, we use zircon oxygen(O) isotopes to track recycling of supracrustal materials into the magma sources of early Archean igneous suites from the Kaapvaal Craton, southern Africa. The mean δ^(18)O values of zircon from TTG(tonalite–trondhjemite–granodiorite) rocks abruptly increase at the Paleo-Mesoarchean boundary(ca.3230 million years ago;Ma), from mantle zircon values of 5‰–6‰ to approaching 7.1‰, and this increase occurs in ≤3230 Ma rocks with elevated Dy/Yb ratios. The^(18)O enrichment is a unique signature of low-temperature water–rock interaction on the Earth’s surface. Because the later phase was emplaced into the same crustal level as the older one and TTG magmas would derive from melting processes in the garnet stability field(>40 km depth), we suggest that this evident shift in TTG zircon O isotopic compositions records the onset of recycling of the mafic oceanic crust that underwent seawater hydrothermal alteration at low temperature. The onset of the enhanced recycling of supracrustal materials may also have developed elsewhere in other Archean cratons and reflects a significant change in the tectonic realm during craton formation and stabilization, which may be important processes for the operation of plate tectonics on early Earth.Xiaolei Wang Ming Tang Jeff Moyen Di Wang Alfred Kröner Chris Hawkesworth Xiaoping Xia Hangqiang Xie Carl Anhaeusser Axel Hofmann Junyong Li Linsen Li 2022National Science Review2022,9,3:3
20HEAT-SHOCK PROTEINS, MOLECULAR CHAPERONES, AND THE STRESS RESPONSE: Evolutionary and Ecological Physiology显示文摘Martin E. Feder Gretchen E. Hofmann 1999Annual Review of Physiology1999,,:3
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