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Decreasing nutrient concentrations in soils and trees with increasing elevation across a treelineecotone in Rolwaling Himal, Nepal

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Journal of Mountain Science 2017年第5期14卷 843-858页

作者： Simon DROLLINGER Michael MULLER Timo KOBL Niels SCHWAB jurgen bohner Udo SCHICKHOFF Thomas SCHOLTEN Geoecology Department of Geography and Regional Research University of Vienna Vienna Austria Soil Science and Geomorphology Department of Geosciences Uniuersity of Tubingen Tubingen Germany CEN Center for Earth System Research and Sustainability Institute of Geography University of Hamburg Hamburg Germany

At a global scale, tree growth in alpine treeline ecotones is limited by low temperatures. At a local scale, however, tree growth at its upper limit depends on multiple interactions of influencing factors and mechanisms. The aim of our research was to understand local scale effects of soil properties and nutrient cycling on tree growth limitation, and their interactions with other abiotic and biotic factors in a near-natural Himalayan treeline ecotone. Soil samples of different soil horizons, litter, decomposition layers, and foliage samples of standing biomass were collected in four altitudinal zones along three slopes, and were analysed for exchangeable cations and nutrient concentrations, respectively. Additionally, soil and air temperature, soil moisture, precipitation, and tree physiognomy patterns were evaluated. Both soil nutrients and foliar macronutrient concentrations of nitrogen(N), magnesium(Mg), potassium(K), and foliar phosphorus(P) decrease significantly with elevation. Foliar manganese(Mn) concentrations, bycontrast, are extraordinarily high at high elevation sites. Potential constraining factors on tree growth were identified using multivariate statistical approaches. We propose that tree growth, treeline position and vegetation composition are affected by nutrient limitation, which in turn, is governed by low soil temperatures and influenced by soil moisture conditions.

关键词： Foliar nutrients Himalaya Nitrogen Nutrient cycling Podzol Treeline

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Implications of tree species–environment relationships for the responsiveness of Himalayan krummholz treelines to climate change

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Journal of Mountain Science 2017年第3期14卷 453-473页

作者： Niels SCHWAB Udo SCHICKHOFF Birgit BURZLE Michael MULLER jurgen bohner Ram Prasad CHAUDHARY Thomas SCHOLTEN Jens OLDELAND CEN Center for Earth System Research and Sustainability Institute of GeographyUniversity of HamburgBundesstrafle 5520146 HamburgGermany Department of Geosciences Chair of Soil Science and CeomorphologyUniversity of TübingenGermany Research Centre for Applied Science and Technology&Central Department of Botany Tribhuvan UniversityNepal Biocentre Klein Flottbek University of HamburgOhnhorststr.1822609 HamburgGermany

Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths （3700-4200 m） at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions （e.g., nutrient and thermal deficits, plant interactions） across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran＇s eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming.

关键词： Himalaya Nepal Population structure Rhododendron campanulatum Spatial patterns Species-environment relationships Stand density Variation partitioning

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Kamenev-type criteria for nonlinear damped dynamic equations

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Science China Mathematics 2015年第7期58卷 1445-1452页

作者： bohner Martin LI TongXing Department of Mathematics and Statistics Missouri University of Science and Technology School of Mathematical Sciences University of Jinan Department of Mathematics Linyi University

We establish a new Kamenev-type theorem for a class of second-order nonlinear damped delay dynamic equations on a time scale by using the generalized Riccati transformation technique. The criterion obtained improves related contributions to the subject. An example is provided to illustrate assumptions in our theorem are less restrictive.

关键词： oscillation second-order dynamic equation nonlinear damped delay equation time scale

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Oscillation of fourth-order delay dynamic equations

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Science China Mathematics 2015年第1期58卷 143-160页

作者： ZHANG Cheng Hui AGARWAL Ravi P. bohner Martin LI Tong Xing School of Control Science and Engineering Shandong University Department of Mathematics Texas A&M University-Kingsville 700 University Blvd.Kingsville TX 78363-8202 USA Department of Mathematics and Statistics Missouri University of Science and TechnologyRolla MO 65409-0020 USA Department of Mathematics Linyi University

This paper is concerned with oscillatory behavior of a class of fourth-order delay dynamic equations on a time *** the general time scales case,four oscillation theorems are presented that can be used in cases where known results fail to *** results obtained can be applied to an equation which is referred to as Swift-Hohenberg delay equation on a time *** criteria improve a number of related contributions to the *** illustrative examples are provided.

关键词： Swift-Hohenberg equation oscillation delay dynamic equation fourth-order time scale

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填料函内软质填料的横向应力比、变形和应力松弛

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化工与通用机械 1981年第10期 51-59页

作者： K. bohner 袁玉球西德Stuttgart大学一机部通用所

本文旨在确定填料函内软质填料的物理性质,以便给出如填料的选择和标准化、计算填料函中填料的接触应力以及判断往复轴和旋转轴填料工作状况所需的特性数据。曾在专用试验装置上,在静载荷下对诸如横向应力比、变形、应力松弛及粘着摩擦... 详细信息

本文旨在确定填料函内软质填料的物理性质,以便给出如填料的选择和标准化、计算填料函中填料的接触应力以及判断往复轴和旋转轴填料工作状况所需的特性数据。曾在专用试验装置上,在静载荷下对诸如横向应力比、变形、应力松弛及粘着摩擦等性能进行过实验测量。对方形截面12.5mm的9种软质填料（例如苎麻、石棉、4F丝、石墨纤维等）的400个试样做过试验。轴向载荷达15MN/m2（150Kgf/cm2—译注）,填料预压比压直到50MN/m2为止,试验时间达100小时。浸油很充分、浸油量少和不浸油的三种填料的填料系数差异悬殊。油浸填料的横向应力比K=σy/σx>0.7;而不浸油填料K=0.3～0.7。用油脂浸渍的填料接触应力的决定因素μ1、K有规律地减小,由于这个原因,使沿填料函的接触应力分布比较均匀。浸油量少的填料摩擦系数μ1为0.12～0.25。含油量较大的填料具有较大的应力松驰是毫无疑问的。

关键词：填料函应力分布接触应力横向应力浸油应力松弛材料动态性质软质

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Overexpression of Arabidopsis YUCCA6 in Potato Results in High-Auxin Developmental Phenotypes and Enhanced Resistance to Water Deficit

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Molecular Plant 2013年第2期6卷 337-349页

作者： Jeong Im Kim Dongwon Baek Hyeong Cheol Park Hyun Jin Chun Dong-Ha Oh Min Kyung Lee Joon-Yung Cha Woe-Yeon Kim Min Chul Kim Woo Sik Chung Hans J. bohner Sang Yeol Lee Ray A. Bressan Shin-Woo Lee Dae-Jin Yun Department of Biochemistry Purdue University West Lafayette IN 47907 USA Division of Applied Life Science (BK21 and WCU Program) Plant Molecular Biology and Biotechnology Research Center Gyeongsang National UniversityJinju 660-701 Republic of Korea Department of Plant Biology University of Illinois at Urbana-Champaign Urbana IL USA Department of Agronomy and Medicinal Plant Resources Gyeongnam National University of Science and Technology Jinju 660-758 Korea Faculty of Science King Abdulaziz University Jeddah 21589 KSA Department of Horticulture Purdue University West Lafayette IN 47907 USA

Indole-3-acetic acid （IAA）, a major plant auxin, is produced in both tryptophan-dependent and tryptophan-independent pathways. A major pathway in Arabidopsis thaliana generates IAA in two reactions from tryptophan. Step one converts tryptophan to indole-3-pyruvic acid （IPA） by tryptophan aminotransferases followed by a rate-limiting step converting IPA to IAA catalyzed by YUCCA proteins. We identified eight putative StYUC （Solanum tuberosum YUCCA） genes whose deduced amino acid sequences share 50%-70% identity with those of Arabidopsis YUCCA proteins. All include canonical, conserved YUCCA sequences： FATGY motif, FMO signature sequence, and FAD-binding and NADP-binding sequences. In addition, five genes were found with -50% amino acid sequence identity to Arabidopsis trypto-phan aminotransferases. Transgenic potato （Solanum tuberosum cv. Jowon） constitutively overexpressing Arabidopsis AtYUC6 displayed high-auxin phenotypes such as narrow downward-curled leaves, increased height, erect stature, and longevity. Transgenic potato plants overexpressing AtYUC6 showed enhanced drought tolerance based on reduced water loss. The phenotype was correlated with reduced levels of reactive oxygen species in leaves. The results suggest a func-tional YUCCA pathway of auxin biosynthesis in potato that may be exploited to alter plant responses to the environment.

关键词： Solanum tuberosum potato Arabidopsis thaliana yuc6-1D YUCCA, StYUCCA, StTAA, auxin, drought.

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如何将Elektrobit SecOC产品机制和Argus入侵检测与防御系统的优势结合

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汽车制造业 2019年第1期 34-36页

作者： ARGUS Yaron Galula Elektrobit Martin bohner 不详

Elektrobit和Argus联合部署Elektrobit SecOC产品机制和Argus入侵检测与防御系统(IDPS),以克服在AUTOSAR与客户就SecOC(Secure Onboard Communication)规范方面提出的安全挑战。

关键词： Argus 防御系统入侵检测机制产品

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用于轿车发动机的新型凸轮轴相位调节器模块

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汽车与新动力 2014年第6期46卷 59-61页

作者： U.Meinig J.bohner 范明强

SHW汽车公司根据可换向液压马达的工作原理开发出一种能快速调节的新型凸轮轴相位调节器。由于使用整体式活塞蓄压器,并对所有零件进行持续不断的流体力学优化,新型凸轮轴相位调节器在确保具有良好调节性能的同时,其调节速度明显高于传... 详细信息

SHW汽车公司根据可换向液压马达的工作原理开发出一种能快速调节的新型凸轮轴相位调节器。由于使用整体式活塞蓄压器,并对所有零件进行持续不断的流体力学优化,新型凸轮轴相位调节器在确保具有良好调节性能的同时,其调节速度明显高于传统的凸轮轴相位调节器。

关键词：凸轮轴相位调节器蓄压器燃油耗

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针对患者利益的机器学习和人工智能研究:在透明性、可重复性、伦理和有效性等方面的20个关键问题

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英国医学杂志中文版 2020年第9期23卷 522-533页

作者： Sebastian Vollmer Bilal A Mateen Gergo bohner Franz J Kirdly Rayid Ghani Pall Jonsson Sarah Cumbers Adrian Jonas Katherine S L McAllister Puja Myles David Granger Mark Birse Richard Branson Karel G M Moons Gary S Collins John P A Chris Holmes Harry Hemingwayp 李峰(译) 徐磊(校) 赵邑(校) Alan Turing Institute Kings CrossLondonUK Departments of Mathematics and Statistics University of WarwickCoventryUK Warwick Medical School University of WarwickCoventryUK Kings College Hospital Denmark HillLondonUK Department of Statistical Science University College LondonLondonUK University of Chicago ChicagoILUSA Science Policy and Research National Institute for Health and Care ExcellenceManchesterUK Health and Social Care Directorate National Institute for Health and Care ExcellenceLondonUK Data and Analytics Group National Institute for Health and Care ExcellenceLondonUK Clinical Practice Research Datalink Medicines and Healthcare products Regulatory AgencyLondonUK Medicines and Healthcare products Regulatory Agency LondonUK Julius Centre for Health Sciences and Primary Care UMC UtrechtUtrecht UniversityUtrechtNetherlands UK EQUATOR Centre Centre for Statistics in MedicineNDORMSUniversity of OxfordOxfordUK Meta-Research Innovation Centre at Stanford Stanford UniversityStanfordCAUSA Department of Statistics University of OxfordOxford 0X13LBUK Health Data Research UK London University College LondonLondon.UK Institute of Health Informatics University College LondonLondonUK National Institute for Health Research University College London Hospitals Biomedical Research CentreUniversity College LondonLondonUK 深圳智影医疗公司首都医科大学附属北京安贞医院清华大学附属北京清华长庚医院皮肤科

机器学习(ML)、人工智能(AI)和其他现代统计方法正为利用先前尚未开发且极速增长的数据资源提供新的机会,以期让患者获益。尽管目前正在进行许多有前景的研究,特别是在图像方面,但就文献整体而言还缺乏透明度、对可重复性清晰的阐述、... 详细信息

机器学习(ML)、人工智能(AI)和其他现代统计方法正为利用先前尚未开发且极速增长的数据资源提供新的机会,以期让患者获益。尽管目前正在进行许多有前景的研究,特别是在图像方面,但就文献整体而言还缺乏透明度、对可重复性清晰的阐述、对潜在伦理问题的探究,以及对有效性的明确验证。这些问题的存在有许多原因,其中最重要的一点(为此我们提供了初步解决方案)就是当前缺乏针对ML和AI的最佳实践指南。我们认为从事研究的跨学科团队和应用ML/AI影响健康的项目,将因解决有关透明度、可重复性、伦理和有效性(TREE)的一系列问题而受益。这里提出的20个关键问题为研究团队提供了一个研究设计、实施和报告框架;帮助编辑和同行评审专家评估文献的贡献;让患者、临床医生和政策制定者评估新发现可能会给患者带来的获益。

关键词：人工智能研究机器学习同行评审数据资源缺乏透明度可重复性透明性跨学科团队

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早期复发好转型多发硬化磁共振波谱成像和磁化传递成像病变负荷和临床评分的断层结合纵向影像的研究

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国际医学放射学杂志 2009年第5期32卷 520-520页

作者： J.Bellmann-Strobl H.Stiepani J.Wuerfel G.bohner F.Paul C.Warmuth 高莉 Department of Neuroradiology Charité-University Medicine BerlinCharitéplatz 110117 BerlinGermany

本研究的目的足评价早期复发好转型多发硬化（RRMS）病人基于MRI的病灶负荷和临床残疾之间的相关性。初诊为RRMS未经治疗的17例病人[女10例，男7例；平均年龄（33．0±7．9）岁]被纳入横断扫描与基于MRI的纵向（24个月）临床和评价，并... 详细信息

本研究的目的足评价早期复发好转型多发硬化（RRMS）病人基于MRI的病灶负荷和临床残疾之间的相关性。初诊为RRMS未经治疗的17例病人[女10例，男7例；平均年龄（33．0±7．9）岁]被纳入横断扫描与基于MRI的纵向（24个月）临床和评价，并且与年龄相匹配的健康对照组进行对比。应用1．5T设备行常规MRI序列、MR波谱（MRS）和磁化传递成像（MTI）检查。

关键词：多发硬化 MR波谱磁化传递成像脑白质

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