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2469篇 您的检索式:作者名="Helm"
    题名 作者 年代 出处 被引量
1中国土地利用多功能性动态的区域分析显示文摘当前,国际学术界针对土地利用的研究正由土地利用格局变化向土地空间多功能变化及其可持续性的方向发展,其宗旨是确定和度量土地多元化利用所提供的产品、服务和功能,及其带来的环境和社会经济效应,实现对土地利用的科学管理。基于可持续发展三维度的理念及其指标体系,界定并定量评价了我国区域土地利用的10项功能,深入研究了在经济快速发展、生态环境保护紧密相随的过去20a间,各项功能的时空变化特征。研究表明,我国土地多功能性的10项功能中,就业支持功能表现出区域增减不一的特点,生态过程维持功能具有高度的稳定性。健康保障、交通功能、居住家园、生物性土地生产、人工化土地生产、资源供给与维持、污染接收器、景观与文化支持功能在各个区域得到了不断改善与提高,但各个功能变化的强势区和弱势区在时空分布上表现出了很强的区域性特点。区域自然条件禀赋、社会经济条件以及土地利用政策在功能变化中起着关键作用。研究结果揭出中国区域土地多功能性尚存在巨大的提升空间;土地政策应具有系统性、功能针对性和时空针对性,并应关注土地利用功能变化的链发效应。甄霖 魏云洁 谢高地 HELMING Katharina 曹淑艳 杨莉 潘影 KOENIG Hannes 2010生态学报2010,30,24:95
2中国土地利用多功能性度量(英文)显示文摘人类活动驱动着土地利用的时空变化,进而导致土地利用功能的变化。中国的土地利用具有高度的动态性,对全球可持续发展具有特别重要的意义。对于决策者来说,要准确预见一项发展政策对土地利用及其功能的复杂影响是非常困难的。本文构建了中国土地利用多功能性的度量框架模型,模拟了2010-2025年期间土地利用变化对国家退耕还林还草政策的响应,并确定了相应的土地利用功能的变化。结果表明,国家退耕还林还草政策显著影响着中国土地利用格局,其特征是随着林地面积的扩大,耕地和草地面积在不断减少。在所度量的所有土地利用功能中,经济功能、社会功能显著增强,调节功能略有增强,而环境净化功能、支持功能明显减弱。通过应用表明,本文构建的中国土地利用多功能性度量框架模型有助于各级政府评价土地利用政策的影响。谢高地 甄霖 张彩霞 邓祥征 Hannes Jochen KOENIG Karen TSCHERNING Katharina HELMING 2010Journal of Resources and Ecology2010,1,4:22
3多功能土地利用 应对未来景观福利和服务需要显示文摘该书是2005年在爱沙尼亚塔图市(Tartu)举行的未来景观网络国际研讨会的论文集,大会主题是“多功能土地利用:应对未来景观福利和服务需要”。传统的土地利用重视土地的生产能力,这种生产能力是同产品产量密切相关的,在对土地的改造中,为了方便运输和管理,大面积种植一种粮食,往往将不同景观特征同质化,Ulo Mander Katharina Helming Hubert Wiggering 龚剑明(博士) 2007国外科技新书评介2007,,12:11
4Physical rehabilitation for lung transplant candidates and recipients: An evidence-informed clinical approach显示文摘Physical rehabilitation of lung transplant candidates and recipients plays an important in optimizing physical function prior to transplant and facilitating recovery of function post-transplant. As medical and surgical interventions in lung transplantation have evolved over time, there has been a demographic shift of individuals undergoing lung transplantation including older individuals, those with multiple co-morbidites, and candidates with respiratory failure requiring bridging to transplantation. These changes have an impact on the rehabilitation needs of lung transplant candidates and recipients. This review provides a practical approach to rehabilitation based on research and clinical practice at our transplant centre. It focuses on functional assessment and exercise prescription during an uncomplicated and complicated clinical course in the pre-transplant, early and late post-transplant periods. The target audience includes clinicians involved in pre- and posttransplant patient care and rehabilitation researchers.Lisa Wickerson Dmitry Rozenberg Tania Janaudis-Ferreira Robin Deliva Vincent Lo Gary Beauchamp Denise Helm Chaya Gottesman Polyana Mendes Luciana Vieira Margaret Herridge Lianne G Singer Sunita Mathur 2016World Journal of Transplantation2016,6,3:8
5MicroRNAs in pancreatic ductal adenocarcinoma显示文摘Ductal adenocarcinoma of the pancreas is a lethal cancer for which the only chance of long-term survival belongs to the patient with localized disease in whom a potentially curative resection can be done. Therefore, biomarkers for early detection and new therapeutic strategies are urgently needed. miRNAs are a recently discovered class of small endogenous non-coding RNAs of about 22 nucleotides that have gained attention for their role in downregulation of mRNA expression at the post-transcriptional level. miRNAs regulate proteins involved in critical cellular processes such as differentiation, proliferation, and apoptosis. Evidence suggests that deregulated miRNA expression is involved in carcinogenesis at many sites, including the pancreas. Aberrant expression of miRNAs may upregulate the expression of oncogenes or downregulate the expression of tumor suppressor genes, as well as play a role in other mechanisms of carcinogenesis. The purpose of this review is to summarize our knowledge of deregulated miRNA expression in pancreatic cancer and discuss the implication for potential translation of this knowledge into clinical practice.Jong Y Park James Helm Domenico Coppola Donghwa Kim Mokenge Malafa Seung Joon Kim 2011World Journal of Gastroenterology2011,17,7:7
6Functional Demarcation of Active and Silent Chromatin Domains in Human HOX Loci by Noncoding RNAs显示文摘John L. Rinn Michael Kertesz Jordon K. Wang Sharon L. Squazzo Xiao Xu Samantha A. Brugmann L. Henry Goodnough Jill A. Helms Peggy J. Farnham Eran Segal Howard Y. Chang 2007Cell2007,,7:6
7MEMS麦克风的应用优势加速取代传统驻极体麦克风显示文摘MEMS麦克风外形较小,与目前广泛采用的驻极体麦克风相比,具备更强的耐热、抗振和防射频干扰性能。强大的耐热性能允许其采用全自动SMT生产工艺,而大多数驻极体麦克风则需手工焊接。这不仅能简化生产流程,降低生产成本,而且能够提供更高的设计自由度和系统成本优势。Roland Helm 2008电子与电脑2008,,3:5
8Antibiotic Treatment Drives the Diversification of the Human Gut Resistome显示文摘Despite the documented antibiotic-induced disruption of the gut microbiota, the impact of antibiotic intake on strain-level dynamics, evolution of resistance genes, and factors influencing resistance dissemination potential remains poorly understood. To address this gap we analyzed public metagenomic datasets from 24 antibiotic treated subjects and controls, combined with an in-depth prospective functional study with two subjects investigating the bacterial community dynamics based on cultivation-dependent and independent methods. We observed that shortterm antibiotic treatment shifted and diversified the resistome composition, increased the average copy number of antibiotic resistance genes, and altered the dominant strain genotypes in an individual-specific manner. More than 30% of the resistance genes underwent strong differentiation at the single nucleotide level during antibiotic treatment. We found that the increased potential for horizontal gene transfer, due to antibiotic administration, was ~3-fold stronger in the differentiated resistance genes than the non-differentiated ones. This study highlights how antibiotic treatment has individualized impacts on the resistome and strain level composition, and drives the adaptive evolution of the gut microbiota.Jun Li Elizabeth A.Rettedal Eric van der Helm Mostafa Ellabaan Gianni Panagiotou Morten O.A.Sommer 2019Genomics, Proteomics & Bioinformatics2019,17,1:4
9人工耳蜗植入的手术技术显示文摘前言 人工耳蜗的作用是刺激听神经,在大脑形成听觉信号.使用这种技术的前提是听觉神经的通路是完整的.已经失去功能的耳蜗用于安放刺激电极(图1,2).Jan Helms 余力生 孔维佳 2004中华耳鼻咽喉科杂志2004,39,10:3
10MEMS麦克风市场潜力巨大显示文摘想象一下不到普通麦克风一半大小,并带有集成音频信号处理功能的微型麦克风.再想象一下可以作为单芯片手机一个集成部分的麦克风.新型MEMS(微型机电系统)麦克风的全部潜能还有待挖掘,但是采用这种技术的产品已经在多种应用中体现出了诸多优势,特别是中高端手机应用中。Roland Helm 2007电子设计应用2007,,5:2
11Up to 70 THz bandwidth from an implanted Ge photoconductive antenna excited by a femtosecond Er:fibre laser显示文摘Phase-stable electromagnetic pulses in the THz frequency range offer several unique capabilities in time-resolved spectroscopy.However,the diversity of their application is limited by the covered spectral bandwidth.In particular,the upper frequency limit of photoconductive emitters-the most widespread technique in THz spectroscopy-reaches only up to 7 THz in the regular transmission mode due to absorption by infrared-active optical phonons.Here,we present ultrabroadband(extending up to 70 THz)THz emission from an Au-implanted Ge emitter that is compatible with mode-locked fibre lasers operating at wavelengths of 1.1 and 1.55μm with pulse repetition rates of 10 and 20 MHz,respectively.This result opens up the possibility for the development of compact THz photonic devices operating up to multi-THz frequencies that are compatible with Si CMOS technology.Abhishek Singh Alexej Pashkin Stephan Winnerl Malte Welsch Cornelius Beckh Philipp Sulzer Alfred Leitenstorfer Manfred Helm Harald Schneider 2020Light(Science & Applications)2020,9,1:2
12离子注入缺陷局域掺杂的高效率硅pn结发光二极管显示文摘本文将硼离子注入n型硅片制备出硅pn结发光二极管,系统研究了硼离子的注入剂量、能量、以及温度等条件对硅pn结电致发光效率的影响。随着注入的B原子浓度的提高,硅pn结二极管的电致发光效率显著增强,在B原子浓度接近2倍于退火温度下的固溶度时,室温下的电致发光效率达到最大值0.12%,比传统的硅pn结发光二极管增强了2-3个数量级。在低温电致发光光谱中,发现了两个来自局部掺杂缺陷的束缚激子发光峰。随着温度的升高,束缚激子的发光峰出现温度猝灭,束缚激子离化为自由电子和空穴,增加了硅带间自由激子复合的发光效率,从而使电致发光呈现随温度增加而增强的反常温度效应。杨阳 孙甲明 张俊杰 张新霞 刘海旭 W. Skorupa M. Helm 2009材料科学与工程学报2009,27,1:2
13Soil erosion under different rainfall intensities, surface roughness, and soil water regimes显示文摘M.J.M R?mkens K Helming S.N Prasad 2002Catena2002,,2:2
14基于语料库的英汉高频复合词语义透明度研究显示文摘本研究结合心理语言学和词汇语义学视角,对英、汉高频各1000个复合词的语义透明度类型进行了数值分析,并将其与复合词的词频进行关联。结果表明:语义完全透明和半透明型复合词在两种语言中比例较高,完全隐晦型复合词所占比例较低;汉语高频复合词的词频与语义透明度分布呈正相关,英语高频复合词的词频与语义透明度分布无明显相关性。这充分体现了英汉词汇结构分布上的共性与差异。马文艳 Rena Helms Park 苏向丽 2014西安外国语大学学报2014,22,3:2
15Food sustainability,food security and the environment显示文摘Martine Helms 2004British Food Journal2004,106,5:1
16Depression and long-term mortality risk in patients with coronary artery disease显示文摘 Helm S Mark D B 1996Am J Cardiol1996,78,6:1
17First evidence supporting a potential role for the BMP/SMAD pathway in the progression of oestrogen receptor-positive breast cancer显示文摘Helms MW Packeisen J August C 2005J Pathol2005,206,3:1
18Porter's generic strategies:An exploratory study of their use in JAPAN显示文摘Allen R S Helms M M Takeda M B 2007Journal of Business Strategies2007,24,1:1
19The viable but non- ctdturable state and starvation are different stress respon- ses of Enterococcus faecalis, as setermined by proteome analysis显示文摘Helm S Lleb MM Bonato B 2002J Bacteriol2002,184,23:1
20Cyopreservation of human platelets with dimethyl sulfoxide; Changse in biochemistry and cell function 显示文摘Bock M Schleuning M Helm mu 1995Transfusion1995,35,:1
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