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Global multifaceted biodiversity patterns,centers,and conservation needs in angiosperms

Science china(Life Sciences) 2024年第4期67卷 817-828页

作者： Ao Luo Yaoqi Li Nawal Shrestha Xiaoting Xu Xiangyan Su Yichao Li Tong Lyu Kilara Waris Zhiyao Tang Xiaojuan Liu Luxiang Lin Yongsheng chen Kuiling Zu Wenqi Song Shijia Peng Niklaus E.zimmermann Loïc Pellissier Zhiheng Wang Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Department of Health and Environmental Sciences Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China State Key Laboratory of Grassland Agro-Ecosystems College of EcologyLanzhou UniversityLanzhou 730000China Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065China Land consolidation and Rehabilitation center Ministry of Natural ResourcesBeijing 100035China State Key Laboratory of Vegetation and Environmental change Institute of BotanyChinese Academy of SciencesBeijing 100093China cAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesKunming 650201China Swiss Federal Research Institute WSL Birmensdorf 8903Switzerland Department of Environmental Systems Science ETH ZürichZürich 8092Switzerland

The convention on Biological Diversity seeks to conserve at least 30%of global land and water areas by 2030,which is a challenge but also an opportunity to better preserve biodiversity,including flowering plants(angiosperms).Herein,we compiled a large database on distributions of over 300,000 angiosperm species and the key functional traits of 67,024 *** this database,we constructed biodiversity-environment models to predict global patterns of taxonomic,phylogenetic,and functional diversity in terrestrial angiosperms and provide a comprehensive mapping of the three diversity *** further evaluated the current protection status of the biodiversity centers of these diversity *** results showed that geographical patterns of the three facets of plant diversity exhibited substantial spatial mismatches and nonoverlapping conservation *** centers of functional diversity,particularly of herbaceous species,were primarily distributed in temperate regions and under weaker protection compared with other biodiversity centers of taxonomic and phylogenetic *** global assessment of multifaceted biodiversity patterns and centers highlights the insufficiency and unbalanced conservation among the three diversity facets and the two growth forms(woody ***),thus providing directions for guiding the future conservation of global plant diversity.

关键词： angiosperms species richness phylogenetic diversity functional diversity plant traits woody species herbaceous species

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Effects of Protein Toxins and Innocuous Dietary Proteins on Indicators of Barrier Integrity,cytotoxicity,and Inflammatory cytokine Production in Human Intestinal Epithelial cell Monolayers

Effects of Protein Toxins and Innocuous Dietary Proteins on ...

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中国毒理学会第七次全国毒理学大会暨第八届湖北科技论坛

作者： Hurley BP Pirzai W Eaton AD Harper M Roper J zimmermann c Ladics GS Layton RJ Delaney B Mucosal Immunology & Biology Research center Massachusetts General Hospital Department of Pediatrics Harvard Medical School

Human derived cells modeling the gastrointestinal barrier were assessed as an in vitro tool for identifying potential for adverse effects following exposure to protein toxins or innocuous dietary *** of cytotoxicity(LDH release,MTT conversion),monolayer barrier integrity([H]-inulin flux,horse radish peroxidase flux,trans-epithelial electrical resistance[TEER]),and production of inflammatory cytokines(IL-8,IL-6) were assessed using human intestinal epithelial cell lines(T84,caco-2,and HcT-8) grown on permeable Transwell filters following addition of purified *** proteins included streptolysin O(from Streptococcus pyogenes),clostridium difficile Toxins A and B,heat-labile toxin from enterotoxigenic Escherichia coli,listeriolysin O(from Listeria monocytogenes),melittin(bee venom),and mastoparan(wasp venom).The allergenic food proteins bovine milk β-lactoglobulin and peanut Ara h 2 and the anti-nutritive food protein wheat germ agglutinin were also *** not expected to cause adverse effects in the intestine included bovine and porcine serum albumin,bovine fibronectin,and ribulose bisphosphate carboxylase/oxygenase(RuBisco) from *** results demonstrated that multiple toxic proteins exerted effects on cytotoxicity and monolayer integrity whereas proteins considered innocuous did *** evaluation of this model is warranted as it may prove useful in hazard analysis for proteins with unknown toxicity profiles.

关键词： Biotechnology In vitro cellular toxicology

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不稳定锂同位素移位的高精度测量实验方案(英文)

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原子核物理评论 2002年第2期19卷 285-289页

作者：王海鸣 A.Dax G.Ewald I.Katayama R.Kirchner W.Nrtershuser H.-J.Kluge T.Kǖhl R.Sanchez I.Tanihata M.Tomaselli c.zimmermann 德国重离子研究中心东京大学日本图宾根大学重离子研究中心

对丰中子晕核11Li的核电荷均方根半径的实验确定 ,特别是其与9Li的半径的差值 ,将对各种核模型进行灵敏的检验 .选择锂的合适跃迁 ,利用激光光谱技术高精度测量该跃迁的同位素移位 ,并扣除精确理论计算的质量移位贡献值 ,可以用来确定... 详细信息

对丰中子晕核11Li的核电荷均方根半径的实验确定 ,特别是其与9Li的半径的差值 ,将对各种核模型进行灵敏的检验 .选择锂的合适跃迁 ,利用激光光谱技术高精度测量该跃迁的同位素移位 ,并扣除精确理论计算的质量移位贡献值 ,可以用来确定有关同位素的核电荷均方根半径 .就目前能够提供的实验设备和手段 ,对于不稳定锂的同位素8,9Li和短寿命丰中子晕核11Li而言 ,这是能够得到与核模型相独立的电荷半径值的唯一可行的方法 .这类实验正在德国重离子研究中心 (GSI)和欧洲核子中心的ISOLDE/cERN上计划实施 .描述了锂原子的激光激发共振电离途径和进行锂的同位素移位测量的实验装置 ,并讨论了采用这种方法测量到的6,7Li的初步结果及其精度 ,以及使用该方法研究不稳定核的灵敏性 .

关键词：锂同位素高精度测量实验方案晕核同位素移位电荷半径半中子不稳定性锂原子核模型

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Systematic Review on Ground-Based cloud Tracking Methods for Photovoltaics Nowcasting

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American Journal of climate change 2024年第3期13卷 452-476页

作者： Juliana Marian Arrais Allan cerentini Bruno Juncklaus Martins Thiago zimmermann Loureiro chaves Sylvio Luiz Mantelli Neto Aldo von Wangenheim PPGcc-INE UFSC Federal University of Santa Catarina Florianpolis Brazil INPE Brazilian National Institute for Space Research So Paulo Brazil

Renewable energies are highly dependent on local weather conditions, with photovoltaic energy being particularly affected by intermittent clouds. Anticipating the impact of cloud shadows on power plants is crucial, as clouds can cause partial shading, excessive irradiation, and operational issues. This study focuses on analyzing cloud tracking methods for short-term forecasts, aiming to mitigate such impacts. We conducted a systematic literature review, highlighting the most significant articles on cloud tracking from ground-based observations. We explore both traditional image processing techniques and advances in deep learning models. Additionally, we discuss current challenges and future research directions in this rapidly evolving field, aiming to provide a comprehensive overview of the state of the art and identify opportunities for significant advancements in the next generation of cloud tracking systems based on computer vision and deep learning.

关键词： Nowcasting Photovoltaic Image Processing

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Turning of aluminum metal matrix composites： influence of the reinforcement and the cutting condition on the surface layer of the workpiece

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Advances in Manufacturing 2016年第3期4卷 225-236页

作者： Jan c. Aurich Marco zimmermann Stefan Schindler Paul Steinmann Institute for Manufacturing Technology and ProductionSystems University of Kaiserslautern KaiserslauternGermany chair of Applied Mechanics University of Erlangen-Nuremberg Erlangen Germany

Aluminum metal matrix composites （Al-MMcs） are difficult to machine. The reinforcement of aluminum using ceramic particles accelerates tool wear. Moreover, demanded machining accuracies or properties of the surface layer are difficult to achieve. In the present study, the effect of silicon carbide reinforcement particles on the surface layer of the workpiece was investigated using multiple cutting conditions for dry turning. Three differently reinforced Al-MMcs regarding the volume percent-age （17% and 30%） and the particle size （0.6 μm and 3 μm） and their non-reinforced matrix were considered as the workpiece materials. The reinforcement and the cutting condition affect the results of turning. A greater particle volume percent improves the surface roughness and decreases the tensile stress in the surface. The smaller particle size caused a lower tensile stress in the surface. A general effect of the particle size on the workpiece roughness can not be concluded. The most important cutting parameter for the surface layer of the workpiece is the feed. Greater feeds decrease the tensile stress in the surface, but deteriorate the surface quality.

关键词： Aluminum metal matrix composite(Al-MMc) Forces . Workpiece roughness Surface Residual stress

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Dynamical behavior of a mobile system with two degrees of freedom near the resonance

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Acta Mechanica Sinica 2011年第1期27卷 7-17页

作者： Klaus zimmermann Igor Zeidis Faculty of Mechanical Engineering Technische Universitaet Ilmenau

The design of mobile robots that can move without wheels or legs is an important engineering and technological ***-propelling mechanisms consisting of a body that has contact with a rough surface and moveable internal masses are *** models of such systems are presented in this ***,a model of a vibration driven robot that moves along a rough horizontal plane with isotropic dry friction is *** is shown that by changing the off-resonance frequency detuning in sign,one can control the direction of motion of the *** addition,a locomotion system which moves in an environment with anisotropic viscous friction is *** all models,the method of averaging to obtain an algebraic equation for the steady-state＂average＂velocity of the system is used. Prototypes were constructed to compare the theoretical results with experimental ones.

关键词： Dynamics Friction Resonance Vibrationdriven systems

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Towards cost-Effective cloud Downloading with Tencent Big Data

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Journal of computer Science & Technology 2015年第6期30卷 1163-1174页

作者：李振华刘刚嵇智源 Roger zimmermann School of Software Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China QQXuanfeng System Group Tencent Co. Ltd Shanghai 200233 China High Technology Research and Development center Ministry of Science and Technology Beijing 10004 China Department of computer Science National University of Singapore Singapore 117417 Singapore

The cloud downloading scheme, first proposed by us in 2011, has effectively optimized hundreds of millions of users＇ downloading experiences. Also, people start to build a variety of useful Internet services on top of cloud downloading. In brief, by using cloud facilities to download （and cache） the requested file from the ＂best-effort＂ Internet on behalf of the user, cloud downloading ensures the data availability and remarkably enhances the data delivery speed. Although this scheme seems simple and straightforward, designing a real-world cloud downloading system involves complicated and subtle trade-offs （between deployment cost and user experience） when serving a large number of users： 1） how to plan the cloud cache capacity to achieve a high and affordable cache hit ratio, 2） how to accelerate the data delivery from the cloud to numerous users, 3） how to handle the dense user requests for highly popular files, and 4） how to judge a potential downloading failure of the cloud. This paper addresses these design trade-offs from a practical perspective, based on big data from a nationwide commercial cloud downloading system, i.e., Tencent QQXuanfeng. Its running traces help us find reasonable design strategies and parameters, and its real performances confirm the efficacy of our design. Our study provides solid experiences and valuable heuristics for the developers of similar and relevant systems.

关键词： cloud downloading cost-effective design trade-off big data

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Embedding compact surfaces into the 3-dimensional Euclidean space with maximum symmetry

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Science china Mathematics 2017年第9期60卷 1599-1614页

作者： WANG chao WANG Shicheng ZHANG YiMu zimmermann Bruno Jonsvannsveien 87B H0201Trondheim 7050Noway School of Mathematical Sciences Peking UniversityBeijing 100871China Mathematics School Jilin UniversityChangehun 130012China Dipartimento di Matematica e Geoseienze Universita degli Studi di TriesteTrieste 34100Italy

The symmetries of surfaces which can be embedded into the symmetries of the 3-dimensional Euclidean space R3 are easier to feel by human＇s intuition. We give the maximum order of finite group actions on （R3 E） among all possible embedded closed/bordered surfaces with given geometric/algebraic genus greater than 1 in R3. We also identify the topological types of the bordered surfaces realizing the maximum order, and findsimple representative embeddings for such surfaces.

关键词： finite group action extendable action symmetry of surface maximum order

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Analysis of the Vibrissa Parametric Resonance causing a Signal Amplification during Whisking Behaviour

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Journal of Bionic Engineering 2016年第2期13卷 312-323页

作者： Tatiana Volkova Igor Zeidis Hartmut Witte Manuela Schmidt Klaus zimmermann Technische Universiat Ilmenau Technical Mechanics Group 98693 Max-Planck-Ring 12 Ilmenau Germany Technische Universitat Ilmenau Biomechatronics Group 98693 Max-Planck-Ring 12 Ilmenau Germany Friedrich-Schiller-Universitat Jena Institute of Systematic Zoology and Evolutionary Biology with Phyletic Museum 07743 Erbertstrafle 1 Jena Germany

The paper deals with the mechanical vibrational motion ofvibrissae during natural exploratory behaviour of mammals. The theoretical analysis is based on a mechanical model of a cylindrical beam with circular natural configuration under an applied periodic force at the tip, which corresponds to the surface roughness of an investigated object. The equation of motion of the beam is studied using the Euler-Bemoulli beam theory and asymptotic methods of mechanics. It is shown that from the me- chanical point of view the phenomenon of parametric resonance of the vibrissa is possible. It means that the amplitude of forced vibrations of a vibrissa increases exponentially with time, if it is stimulated within a specific resonance frequency range, which depends on biomechanical parameters of the vibrissa. The most intense parametric resonance occurs, when the excitation frequency is close to the doubled natural frequency of free vibrations. Thus, it may be used to distinguish and amplify specific periodic components of a complex roughness profile during texture discrimination.

关键词： vibrissa whisking vibration tactile sensor beam theory parametric resonance

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Skyline-join query processing in distributed databases

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Frontiers of computer Science 2016年第2期10卷 330-352页

作者： Mei BAI Junchang XIN Guoren WANG Roger zimmermann Xite WANG college of Information Science and Engineering Northeastern University Shenyang 110819 China School of computing National University of Singapore Singapore 117417 Singapore

The skyline-join operator, as an important variant of skylines, plays an important role in multi-criteria decision making problems. However, as the data scale increases, previous methods of skyline-join queries cannot be applied to new applications. Therefore, in this paper, it is the first attempt to propose a scalable method to process skyline-join queries in distributed databases. First, a tailored distributed framework is presented to facilitate the computation of skyline-join queries. Second, the distributed skyline-join query algorithm （DSJQ） is designed to process skyline-join queries. DSJQ contains two phases. In the first phase, two filtering strategies are used to filter out unpromising tuples from the original tables. The remaining tuples are transmitted to the corresponding data nodes according a partition function, which can guarantee that the tuples with the same join value are transferred to the same node. In the second phase, we design a scheduling plan based on rotations to calculate the final skyline-join result. The scheduling plan can ensure that calculations are equally assigned to all the data nodes, and the calculations on each data node can be processed in parallel without creating a bottleneck node. Finally, the effectiveness of DSJQ is evaluated through a series of experiments.

关键词： skyline-join distributed filtering strategy scheduling plan rotation

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