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Micro-site Conditions of Epiphytic Orchids in a Human Impact Gradient in Kathmandu Valley, Nepal

Journal of Mountain science 2012年第3期9卷 331-342页

作者： Yagya Prasad ADHIKARI Anton FISCHER Hagen Siegfried FISCHER Geobotany Department of Ecology and Ecosystem Management Technische Universitt München Hans-Carl-von-Carlowitz-Platz 2 D-85354 Freising Germany

We studied distribution and site conditions of epiphytic orchids in a gradient of human interference in Kathmandu valley, central Nepal. The aim was to understand the recent distribution pattern of epiphytic orchids, with respect to (i) the micro-site conditions and (ii) the type and intensity of land use. The occurrence of epiphytic orchids was recorded for a grid with 1.5 km cell size. The cells represent different types and intensities of human impact. Site factors such as bark rugosity, bark pH, diameter at breast height (dbh; 1.3 m) of host trees, exposure to wind and sunlight intensity were recorded. With regard to the species richness and abundance of epiphytic orchids, we compared different human impact categories from very strong human impact (settlement area) to very low human impact (national park). Remote sensing was used for a supervised classification of land cover. Ficus religiosa turned out to be the most important host species for orchids in urban areas, while Schima wallichii and Alnus nepalensis significantly host orchids in the other categories. Both species richness and abundance of epiphytic orchids were significantly higher under very low human impact (forest in national park) and also some remaining patches of primary forest than the other regions. Micro-climate is crucial for orchid populations. Host bark pH, bark rugosity, sunlight intensity and host exposure were significantly different for all human impact categories in order to harbour epiphytic orchid species. Habitats with a mixture of mature trees are suitable and essential for the conservation of viable populations of epiphytic orchids in settled areas. The study reveals that to improve the population size of orchids it is essential for future urban forestry to: (i) Protect old trees as carriers of existing epiphytic orchid diversity, (ii) protect medium old trees to ensure that they may become old trees, (iii) plant new host trees for the future, (iv) plant in groups instead of sing

关键词： Human impact Host tree Micro-climate Epiphytic orchids Remote sensing Conservation Nepal

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Exploring the potential of extrachromosomal DNA as a novel oncogenic driver

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science China Life sciences 2025年第1期68卷 144-157页

作者： Huanbo Zhu Longtao Huangfu Junbing Chen Jiafu Ji Xiaofang Xing Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing) Division of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute department of Gastrointestinal Cancer Center Peking University Cancer Hospital & Institute department of Liver Surgery & Transplantation Liver Cancer InstituteZhongshan HospitalFudan University Key Laboratory of Carcinogenesis and Cancer Invasion Ministry of Education State Key Laboratory of Holistic Integrative management of Gastrointestinal Cancers Beijing Key Laboratory of Carcinogenesis and Translational ResearchDivision of Gastrointestinal Cancer Translational Research LaboratoryPeking University Cancer Hospital & Institute

Extrachromosomal DNA(ecDNA) is a form of circular DNA mostly found in tumor cells. Unlike the typical chromosomal DNA, ecDNA is circular, self-replicating, and carries complete or partial gene fragments. Although ecDNA occurrence remains a rare event in cancer, recent studies have shown that oncogene amplification on ecDNA is widespread throughout many types of cancer, implying that ecDNA plays a central role in accelerating tumor evolution. ecDNA has also been associated with increased tumor mutation burden, chromosomal instability, and even tumor microenvironment remodeling. ecDNA may be crucial in influencing tumor heterogeneity, drug sensitivity,oncogenic senescence, and tumor immunogenicity, leading to a worsening prognosis for tumor patients. In this way, several clinical trials have been conducted to investigate the importance of ecDNA in clinical treatment. In this review, we summarize the biogenesis, characteristics, and current research methods of ecDNA, discuss the vital role of ecDNA-caused tumor heterogeneity in cancers, and highlight the potential role of ecDNA in cancer therapy.

关键词： extrachromosomal DNA cancer therapy tumor heterogeneity drug resistance tumor evolution

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Design and Implementation of Verification Code Identification Based on Anisotropic Heat Kernel

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China Communications 2016年第1期13卷 100-112页

作者： LIU Lizhao LIU Jian DAI Yaomei XU Huarong YIN Huayi ZHU Shunzhi department of Computer science and Technology Xiamen University of Technology department of management Nanjing University of Science and Technology

Many websites use verification codes to prevent users from using the machine automatically to register,login,malicious vote or irrigate but it brought great burden to the enterprises involved in internet marketing as entering the verification code *** the verification code security system needs the identification method as the corresponding testing *** propose an anisotropic heat kernel equation group which can generate a heat source scale space during the kernel evolution based on infinite heat source axiom,design a multi-step anisotropic verification code identification algorithm which includes core procedure of building anisotropic heat kernel,settingwave energy information parameters,combing outverification codccharacters and corresponding peripheral procedure of gray scaling,binarizing,denoising,normalizing,segmenting and identifying,give out the detail criterion and parameter *** test show the anisotropic heat kernel identification algorithm can be used on many kinds of verification code including text characters,mathematical,Chinese,voice,3D,programming,video,advertising,it has a higher rate of 25%and 50%than neural network and context matching algorithm separately for Yahoo site,49%and 60%for Captcha site,20%and 52%for Baidu site,60%and 65%for 3DTakers site,40%,and 51%.for MDP site.

关键词： verification code image recognition data mining scale space anisotropic heat kernel

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Multi-Embed Nonlinear Scale-Space for Image Trust Root Generation

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China Communications 2016年第11期13卷 170-179页

作者： Lizhao Liu Wentu Gao Jian Liu Huayi Yin Huarong Xu Shunzhi Zhu department of Computer science and Technology Xiamen University of Technology department of management Nanjing University of Science and Technology

An image trust root is a special type of soft trust root for trusted computing. However,image trust root generation is difficult,as it needs a corresponding stable logic feature generation model and algorithm for dynamical and sustained authentication. This paper proposes a basic function of constructing new scale-spaces with deep detecting ability and high stability for image features aimed at image root generation. According to the heat distribution and spreading principle of various kinds of infinitesimal heat sources in the space medium,a multi-embed nonlinear diffusion equation that corresponds to the multi-embed nonlinear scale-space is proposed,a HARRIS-HESSIAN scale-space evaluation operator that aims at the structure acceleration characteristics of a local region and can make use of image pixels' relative spreading movement principle was constructed,then a single-parameter global symmetric proportion(SPGSP) operator was also constructed. An authentication test with 3000 to 5000 cloud entities shows the new scale-space can work well and is stable,when the whole cloud has 5%-50% behavior with un-trusted entities. Consequently,it can be used as the corresponding stable logic feature generation model and algorithm for all kinds of images,and logic relationships among image features for trust roots.

关键词： image trust root scale-space diffusion equation evolution operator feature detection

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Does white-tailed deer density affect tree stocking in forests of the Eastern United States?

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Ecological Processes 2019年第1期8卷 371-382页

作者： Brice B.Hanberry Marc D.Abrams USDA Forest Service Rocky Mountain Research StationRapid CitySD 57702USA department of ecosystem science and management Pennsylvania State University307 Forest Resources BldgUniversity ParkPA16802USA

Background:White-tailed deer(Odocoileus virginianus)have increased during the past century in the *** deer densities may reduce tree regeneration,leading to forests that are understocked,where growing space is not filled completely by *** deer pressure,a major transition in eastern forests has resulted in increased tree ***:To reconcile conflicting trends,we applied generalized linear mixed models to compare deer densities during 1982 and then 1996 to tree stocking after about 30 years and 15 years of potential reductions of small trees by deer,for the entire eastern US and 11 ecological *** also compiled deer browse preferences and compared preferred browse with trends in tree species composition from historical(1620–1900)and current tree ***:The forested area of the eastern US,including a prairie ecological province,was equally well-stocked(52%)and understocked(48%)during 2011–2017 tree *** 1982 deer densities,38%of area had deer densities>5.8 deer/km2 and for 1996,66%of area had deer densities>5.8 deer/*** densities and tree stocking were not related significantly for the entire eastern *** may reduce tree stocking in the Laurentian Mixed Forest;however,this province had both lower deer densities and greater tree stocking than other ***,major tree species trends did not match tree browse ***:Rather than too few trees,too many trees is an ecological problem where historical open oak and pine forests had herbaceous understories,and currently,trees have captured growing *** attribute other drivers than deer to explain this transition.

关键词： Driver Fire Herbivory Open forests Transition Tree density

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Seasonal Variability in Soil Inorganic Nitrogen Across Borders Between Woodland and Farmland in the Songnen Plain of Northeast China

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Pedosphere 2013年第4期23卷 472-481页

作者： LIN Chang-Cun FU Yao LIU Li WANG Kun WANG De-Li The Academy of Forestry Beijing Forestry University department of Grassland science China Agricultural University Institute of Grassland science Key Laboratory of Vegetation Ecology Northeast Normal University and Key Laboratory of Ecological Restoration and Ecosystem Management of Jilin Province Chinese Research Academy of Environmental sciences

To study the seasonal variability of soil inorganic nitrogen （N） across borders at the woodland-farmland ecotone and potential mechanisms, contents of soil inorganic N were measured during the dry season （May 20 and June 30） and the rainy season （August 10 and September 20） of 2006 in the Songnen Plain of Northeast China. The borders between farmland and woodland were determined by a border-and-ecotone detection analysis （BEDA）. The ecotone limits, often referred to as the depth-of-edge influence （DEI）, are critical for determining the scale at which edge effect operates. The results showed that the soil inorganic N border between the woodland and farmland was located further toward the woodland interior during the rainy season （DEI -- 53.4 ：k 8.7 m, August 10） than during the dry season （DEI = 35.0 =k 12.6 m, May 20）. The seasonal variability in the soil inorganic N border was found to be associated with seasonal changes of deposition flux of N （the correlation coefficients between them for the dry season and rainy season were 0.61 and 0.67, respectively）, which resulted from foliation patterns of trees and crops. Accordingly, the leaf area index at woodland edges was lower than that in the woodland interior, so woodland edges captured large amounts of atmosphere nitrogen deposition. The average DEI was 44.1 m, which was in accordance with the values of other temperate forest boundaries in literatures; therefore, BEDA was an appropriate method to estimate the borders of ecotones.

关键词： depth-of-edge influence ecotone semi-arid woodland edge

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Fast action on short-lived climate pollutants and nature-based solutions to help countries meet carbon neutrality goals

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Advances in Climate Change Research 2022年第4期13卷 564-577页

作者： Xiaopu SUN Pu WANG Tad FERRIS Hui LIN Gabrielle DREYFUS Bai-He GU Durwood ZAELKE Yi WANG Institute for Governance&Sustainable Development Washington DC20016USA Institutes of science and Development Chinese Academy of SciencesBeijing 100190China School of Public Policy and management University of Chinese Academy of SciencesBeijing 100049China department of Physics Georgetown UniversityWashington DC20057USA Bren School of Environmental science&management University of California Santa BarbaraSanta Barbara CA 93106USA

Scientific studies show that fast actions to reduce near-term warming are essential to slowing self-reinforcing climate feedbacks and avoiding irreversible tipping *** cutting CO_(2) emissions only marginally impacts near-term warming,This study identifies two of the most ffective mitigation strategies to limit near-term warming beyond CO_(2) mitigation,namely reducing short-lived climate pollutants(SLCPs)and promoting targeted nature-based solutions(NbS),and comprehensively reviews the latest scientifie progress in these *** show that quickly reducing SLCP emissions,particularly hydrofuorocarbons(HFCs),methane,and black carbon,from ll relevant sectors can avoid up to 0.6℃ of warming by ***,promoting targeted NbS that protect and enhance natural carbon sinks ncluding in forests,wetlands,grasslands,and agricultural lands,can avoid emssions of 23.8 Gt of CO_(2)e per year in 2030,without jeopardizing food security and *** on the scientific evidence,we provided a series of policy recommendations on SLCPs and NbS,including:1)implementing the Kigali Amendment to reduce HFC emissions;2)deploying cost-effective,sector-based measures to reduce methane and black carbon emissions;and 3)implementing targeted NbS to protect and enhance existing carbon sinks and shifting away from forest-burning *** fast-acting strategies on SLCPs and NbS will play a key role in securing the most avoided warming in the near-term and help countries meet their mid-century carbon neutrality ***,we proposed future research topics,including:improving measurement and monitoring systems and techniques for SLCP emissions;developing and improving assessments of marginal abatement costs for SLCP mitigation in dfferent sectors;better quantifying the avoided warming potential from protecting dfferent types of natural carbon sinks by 2030,2050,and over longer periods;and identifying whether there are any biomass types for energy sources that

关键词： Non-CO_(2)mitigation Short-lived elimate pollutants Climate feedbacks and tipping points Near-term warming Methane Hydrofuorocarbons(HFCs) Black carbon Nature-based solutions(NbS)

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Toward Human-centered XAIin Practice:A survey

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Machine Intelligence Research 2024年第4期21卷 740-770页

作者： Xiangwei Kong Shujie Liu Luhao Zhu department of Data science and management Engineering School of ManagementZhejiang UniversityHangzhou 310058China

Human adoption of artificial intelligence(AI)technique is largely hampered because of the increasing complexity and opacity of AI *** AI(XAI)techniques with various methods and tools have been developed to bridge this gap between high-performance black-box AI models and human ***,the current adoption of XAI technique stil lacks"human-centered"guidance for designing proper solutions to meet different stakeholders'needs in XAI *** first summarize a human-centered demand framework to categorize different stakeholders into five key roles with specific demands by reviewing existing research and then extract six commonly used human-centered XAI evaluation measures which are helpful for validating the effect of *** addition,a taxonomy of XAI methods is developed for visual computing with analysis of method *** clearer human demands and XAI methods in mind,we take a medical image diagnosis scenario as an example to present an overview of how extant XAI approaches for visual computing fulfil stakeholders'human-centered demands in *** we check the availability of open-source XAI tools for stakeholders'*** survey provides further guidance for matching diverse human demands with appropriate XAI methods or tools in specific applications with a summary of main challenges and future work toward human-centered XAI in practice.

关键词： Artificial intelligence(AI)application explainable AI(XAI) human-centered design visual computing medical diagnosis.

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Analysis of Classical Encryption Techniques in Cloud Computing

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Tsinghua science and Technology 2016年第1期21卷 102-113页

作者： Muhammad Yasir Shabir Asif Iqbal Zahid Mahmood Ata Ullah Ghafoor department of Computer science University of Management Science and Information School of Computer & Communication Engineering University of Science and TechnologyBeijing department of Computer science National University of Modern Languages

Cloud computing has become a significant computing model in the IT industry. In this emerging model,computing resources such as software, hardware, networking, and storage can be accessed anywhere in the world on a pay-per-use basis. However, storing sensitive data on un-trusted servers is a challenging issue for this model. To guarantee confidentiality and proper access control of outsourced sensitive data, classical encryption techniques are used. However, such access control schemes are not feasible in cloud computing because of their lack of flexibility, scalability, and fine-grained access control. Instead, Attribute-Based Encryption（ABE） techniques are used in the cloud. This paper extensively surveys all ABE schemes and creates a comparison table for the key criteria for these schemes in cloud applications.

关键词： cloud computing access control fine-grained access weighted attribute

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GRAPHICAL-BASED RELIABILITY EVALUATION OF MULTIPLE DISTINCT PRODUCTION LINES

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Journal of Systems science and Systems Engineering 2013年第1期22卷 73-92页

作者： Yi-Kuei LIN Ping-Chen CHANG department of Industrial management National Taiwan University of Science & Technology

This paper proposes a graphical-based methodology to evaluate the performance of a manufacturing system in terms of network *** focus on a manufacturing system which consists of multiple distinct production lines.A transformation technique is developed to build the manufacturing system as a manufacturing *** such a manufacturing network,the capacity of each machine is multistate due to failure,partial failure,or ***,this manufacturing network is also regarded as a multistate *** evaluate the probability that the manufacturing network can meet a given demand,where the probability is referred to as the system reliability.A simple algorithm integrating decomposition technique is proposed to generate the minimal capacity vectors that machines should provide to eventually satisfy *** system reliability is derived in terms of such capacity vectors afterwards.A practical application in the context of IC card manufacturing system is utilized to demonstrate the performance evaluation procedure.

关键词： Graphical-based methodology transformation decomposition multiple distinct production lines system reliability

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