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

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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

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

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

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

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

Combined inhibitors of angiogenesis and histone deacetylase:Efficacy in rat hepatoma

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World Journal of Gastroenterology 2011年第31期17卷 3623-3629页

作者： Marion Ganslmayer Annette zimmermann steffen Zopf Christoph Herold Medical Department 1 University hospital Erlangen-Nuernberg Department of Otolaryngology University of Marburg

AIM:To evaluate the antitumoral effect of combined inhibitors of angiogenesis and histone deacetylases in an experimental rat hepatoma ***:MH7777A hepatoma cells were injected into the liver of male Buffalo *** 7 d treatment with the vascular endothelial growth factor receptor antagonist PTK787/ZK222584(PTK/ZK),the histone deacetylase inhibitor Ms-275,tamoxifen(TAM) and/or retinoic acid was initiated(n ≥ 8 animals/group).Natural tumor development was shown in untreated control groups(control 1 with n = 12,control 2 with n = 8).The control groups were initiated at different time points to demonstrate the stability of the hepatoma *** documentation of possible side effects,we documented any change in body weight,loss of fur and *** 21 d treatment,the rats were *** target parameters were tumor size and metastasis ***,immunohistochemistry for the proliferating cell nuclear antigen(PCNA) and TdT-mediated dUTP-biotin nick end labeling(TUNEL) assay were ***:The control groups developed large tumor nodules with extrahepatic tumor burden in the lung and abdominal organs(control 1:6.18 cm3 ± 4.14 cm3 and control 2:8.0 cm3 ± 4.44 cm3 28 d after tumor cell injection).The tumor volume did not differ significantly in the control groups(P = 0.13).As single agents Ms-275 and PTK/ZK reduced tumor volume by 58.6% ± 2.6% and 48.7% ± 3.2% vs control group 1,which was significant only for Ms-275(P = 0.025).The combination of Ms-275 and PTK/ZK induced a nearly complete and highly significant tumor shrinkage by 90.3% ± 1%(P = 0.005).Addition of TAM showed no further efficacy,while quadruple therapy with retinoic acid increased antitumoral efficacy(tumor reduction by 93 ± 1%) and side *** positive cells were not significantly reduced by the single agents,while dual therapy(Ms-275 and PTK/ZK) and quadruple therapy reduced the PCNA-positive cell fraction significantly by 9.1 and 20.6% vs control 1(P < 0.05).Th

关键词： PTK787 ZK222584 Ms-275 Hepatocellular carcinoma Histone deacetylase inhibitor

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

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

Risk factors and outcome of bacterial infections in cirrhosis

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World Journal of Gastroenterology 2014年第10期20卷 2542-2554页

作者： Tony Bruns Henning W zimmermann Andreas stallmach Department of Internal Medicine IV Jena University Hospital Friedrich Schiller University Jena 07740 Jena Germany Integrated Research and Treatment Center - Center for sepsis Control and Care Jena University Hospital Friedrich Schiller University Jena 07740 JenaGermany Department of Medicine III University Hospital Aachen 52074 Aachen Germany

Viable and non-viable pathological bacterial translocation promote a self-perpetuating circle of dysfunctional immune activation and systemic inflammation facilitating infections and organ failure in advanced *** infections and sepsis are now recognized as a distinct stage in the natural progression of chronic liver disease as they accelerate organ failure and contribute to the high mortality observed in decompensated *** increasing knowledge of structural,immunological and hemodynamic pathophysiology in advanced cirrhosis has not yet translated into significantly improved outcomes of bacterial infections over the last ***,early identification of patients at the highest risk for developing infections and infectionrelated complications is required to tailor the currently available measures of surveillance,prophylaxis and therapy to the patients in need in order to improve the detrimental outcome of bacterial infections in cirrhosis.

关键词： Immunity Infection Cirrhosis Chronic liver disease Bacterial translocation Risk factors Mortality