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69篇 您的检索式:作者名="LI KePing"
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1Climate and litter C/N ratio constrain soil organic carbon accumulation显示文摘Soil organic carbon(SOC) plays critical roles in stabilizing atmospheric CO2 concentration, but the mechanistic controls on the amount and distribution of SOC on global scales are not well understood. In turn, this has hampered the ability to model global C budgets and to find measures to mitigate climate change. Here, based on the data from a large field survey campaign with 2600 plots across China’s forest ecosystems and a global collection of published data from forested land, we find that a low litter carbon-to-nitrogen ratio(C/N) and high wetness index(P/PET, precipitation-to-potentialevapotranspiration ratio) are the two factors that promote SOC accumulation, with only minor contributions of litter quantity and soil texture. The field survey data demonstrated that high plant diversity decreased litter C/N and thus indirectly promoted SOC accumulation by increasing the litter quality. We conclude that any changes in plant-community composition, plant-species richness and environmental factors that can reduce the litter C/N ratio, or climatic changes that increase wetness index, may promote SOC accumulation. The study provides a guideline for modeling the carbon cycle of various ecosystem scales and formulates the principle for land-based actions for mitigating the rising atmospheric CO2 concentration.Guoyi Zhou Shan Xu Philippe Ciais Stefano Manzoni Jingyun Fang Guirui Yu Xuli Tang Ping Zhou Wantong Wang Junhua Yan Gengxu Wang Keping Ma Shenggong Li Sheng Du Shijie Han Youxin Ma Deqiang Zhang Juxiu Liu Shizhong Liu Guowei Chu Qianmei Zhang Yuelin Li Wenjuan Huang Hai Ren Xiankai Lu Xiuzhi Chen 2019National Science Review2019,6,4:21
2Interspecific and intraspecific variation in specific root length drives aboveground biodiversity effects in young experimental forest stands显示文摘Aims Although the net biodiversity effect(NE)can be statistically partitioned into complementarity and selection effects(CE and SE),there are different underlying mechanisms that can cause a certain partitioning.Our objective was to assess the role of resource partitioning and species interactions as two important mechanisms that can bring about CEs by interspecific and intraspecific trait variation.Methods We measured tree height of 2493 living individuals in 57 plots and specific root length(SRL)on first-order roots of 368 of these individuals across different species richness levels(1,2,4,8 species)in a large-scale forest biodiversity and ecosystem functioning experiment in subtropical China(BEF-China)established in 2009.We describe the effects of resource partitioning between species by a fixed component of interspecific functional diversity(RaoQ)and further effects of species interactions by variable components of interspecific and intraspecific functional diversity(community weighted trait similarity and trait dissimilarity,CWS and CWD).Finally,we examined the relationships between biodiversity effects on stand-level tree height and functional diversity(RaoQ,CWS and CWD)in SRL using linear regression and assessed the relative importance of these three components of functional diversity in explaining the diversity effects.Important Findings Our results show that species richness significantly affected SRL in five and tree height in ten out of 16 species.A positive NE was generally brought about by a positive CE on stand-level tree height and related to high values of RaoQ and CWS in SRL.A positive CE was related to high values of all three components of root functional diversity(RaoQ,CWS and CWD).Our study suggests that both resource partitioning and species interactions are the underlying mechanisms of biodiversity effects on stand-level tree growth in subtropical forest.Wensheng Bu Bernhard Schmid Xiaojuan Liu Ying Li Werner Härdtle Goddert von Oheimb Yu Liang Zhenkai Sun Yuanyuan Huang Helge Bruelheide Keping Ma 2017Journal of Plant Ecology2017,10,1:18
3Expression of non-structural protein NS3 gene of Bombyx mori densovirus (China isolate)显示文摘The invertebrate parvovirus Bombyx mori Densonucleosis Virus type 3 (China isolate), named BmDNV-3, is a kind of bidensovirus. It is a new type of virus with unique replication mechanisms. To investigate the effects of the NS3 gene during viral DNA replication, a pair of primers was designed for amplifying NS3 gene of Bombyx mori densovirus (China isolate). Gene NS3 amplified was cloned into a prokaryotic expression vector pET-30a and the donor plasmid pFastBacHTe, respectively. The NS3 protein was expressed in Escherichia coli BL21. The pFastBacHTe-NS3 was transformed to E. coli DH10Bac. The recombinant bacmid baculoviruses (rBacmid-EGFP-NS3) isolated from the white colonies were transfected into BmN-4 cells using a transfection reagent. BmN-4 cells were infected with recom-binant virus to express fusion proteins. The expression of fusion protein around 30 kDa in E. coli BL21 was identified by SDS-PAGE, Western blotting, and mass spectrometry. The expressed NS3 protein by B. mori nucleopolyhedrovirus bacmid system was confirmed by Western blotting using an anti-NS3 polyclonal antibody. And about 45 kDa protein was found. The expressed fusion protein was smaller than the expected size of EGFP-NS3, 55 kDa. Western blotting analysis indicated that EGFP-NS3 protein was expressed in infected lar-vae with smaller molecular size.Huijuan Yin Qin Yao Zhongjian Guo Fang Bao Wei Yu Jun Li Keping Chen 2008Journal of Genetics and Genomics2008,35,4:7
4Impact of tree diversity and environmental conditions on the survival of shrub species in a forest biodiversity experiment in subtropical China显示文摘Aims Although shrubs are an important component of forests,their role has not yet been considered in forest biodiversity experiments.In the biodiversity-ecosystem functioning(BEF)experiment with subtropical tree species in south-east China(BEF-China),we factorially combined tree with shrub species-diversity treatments.Here,we tested the hypotheses that shrub survival differs between the 10 planted shrub species,with lower survival rates of late-than early-successional species and is affected by environmental conditions,such as topography and top soil characteristics,as well as by biotic factors,represented by tree,shrub and herb layer characteristics.Methods We analyzed the survival of 42000 shrub individuals in 105 plots varying in tree and shrub species richness of the BEF-China project four years after planting.Shrub survival was analyzed with generalized linear mixed effects models at the level of individuals and with variance partitioning at the plot level.Random intercept and random slope models of different explanatory variables were compared with respect to the Bayesian Information Criterion(BIC).Important Findings Survival rates differed largely between the 10 shrub species,ranging from 26%to 91%for Ardisia crenata and Distylium buxifolium,respectively.Irrespective of species identity,single abiotic factors explained up to 5%of species survival,with a negative effect of altitude and slope inclination and a positive effect of the topsoil carbon to nitrogen ratio,which pointed to drought as the major cause of shrub mortality.In contrast,neither tree nor shrub richness affected shrub survival at this early stage of the experiment.Among the biotic predictors,only herb layer species richness and cover of the dominant fern species(Dicranopteris pedata)affected shrub survival.Overall,our models that included all variables could explain about 65%in shrub survival,with environmental variables being most influential,followed by shrub species identity,while tree species diversity(species richness and identity)and herb layer characteristics contributed much less.Thus,in this early stage of the experiment the biotic interactions among shrubs and between shrubs and trees have not yet overruled the impact of abiotic environmental factors.Bo Yang Ying Li Bingyang Ding Sabine Both Alexandra Erfmeier Werner Härdtle Keping Ma Bernhard Schmid Thomas Scholten Gunnar Seidler Goddert von Oheimb Xuefei Yang Helge Bruelheide 2017Journal of Plant Ecology2017,10,1:7
5Bombyx mori bidensovirus:The type species of the new genus Bidensovirus in the new family Bidnaviridae显示文摘Bombyx mori bidensovirus(BmBDV),which had been assigned to Densovirinae in Parvoviridae previously,replicates mainly in silkworm midgut columnar cells and causes the fatal flacheric disease.In contrast to parvovirus,this virus possesses two single-stranded DNA genome segments and encodes a putative protein-primed DNA polymerase.The accumulating evidence suggests that it has unique characteristics different to parvovirus and adopts its own mechanisms for replication.So far,little is known about the replication mechanisms of BmBDV.In this review,we focus on the pathology associated with this virus and the viral biology such as viral genome structure,viral genes,and viral replication and expression strategies.HU ZhaoYang LI GuoHui LI GuangTian YAO Qin CHEN KePing 2013Chinese Science Bulletin2013,58,36:6
6Formal verification of safety protocol in train control system显示文摘In order to satisfy the safety-critical requirements,the train control system(TCS) often employs a layered safety communication protocol to provide reliable services.However,both description and verification of the safety protocols may be formidable due to the system complexity.In this paper,interface automata(IA) are used to describe the safety service interface behaviors of safety communication protocol.A formal verification method is proposed to describe the safety communication protocols using IA and translate IA model into PROMELA model so that the protocols can be verified by the model checker SPIN.A case study of using this method to describe and verify a safety communication protocol is included.The verification results illustrate that the proposed method is effective to describe the safety protocols and verify deadlocks,livelocks and several mandatory consistency properties.A prototype of safety protocols is also developed based on the presented formally verifying method.ZHANG Yan TANG Tao LI KePing MERA Jose Manuel ZHU Li ZHAO Lin XU TianHua 2011Science China(Technological Sciences)2011,54,11:6
7Modeling and simulation for train control system using cellular automata显示文摘Train control system plays a key role in railway traffic. Its function is to manage and control the train movement on railway networks. In our previous works, based on the cellular automata (CA) model, we proposed several models and algorithms for simulating the train movement under different control system conditions. However, these models are only suitable for some simple traffic conditions. Some basic fac- tors, which are important for train movement, are not considered. In this paper, we extend these models and algorithms and give a unified formula. Using the pro- posed method, we analyze and discuss the space-time diagram of railway traffic flow and the trajectories of the train movement. The numerical simulation and analytical results demonstrate that the unified CA model is an effective tool for simulating the train control system.LI KePing GAO ZiYou YANG LiXing 2007Science China(Technological Sciences)2007,50,6:6
8Foraging strategies in the greater horseshoe bat(Rhinolophus ferrumequinum)on Lepidoptera in summer显示文摘The diet of the bat Rhinolophus ferrumequinum was studied at the Zhi’an Village of Ji’an City in China, from June to August 2004. The bats were trained in a laboratory (volume: 9×4×4 m3). Foraging strategies of the bat were ob- served at night and prey remains were collected and identi- fied. The results showed that the diet consisted mainly of Lepidoptera in summer, including 11 families, more than 30 species of moths, such as Noctuidae (36.6% by number), Sphingidae (24.1%), Geometridae (13.4%) and Limacodidae (9.5%). The length of culled wings ranged from 10―40 mm (97.7%). Pearson correlation analysis showed that the bat R. ferrumequinum foraged their prey selectively, but not op- portunistically. From field studies, two ways were observed in which the bats retrieved their prey including aerial hawk- ing during peak active period of the insects and flycatching during the insects’ non-peak activity period. The bats never gleaned prey from the ground, though they appeared to be well able to detect fluttering moths on the ground.JIN Longru FENG Jiang SUN Keping LIU Ying WU Lei LI Zhenxin ZHANG Xichen 2005Chinese Science Bulletin2005,50,14:5
9Optimal pilots design for frequency offsets and channel estimation in OFDM modulated single frequency networks显示文摘Optimal pilot design and placement for both the frequency offsets and channel estimation in Orthogonal Frequency-Division Multiplexing modulated Single Frequency Network are treated.Unlike the conventional frequency-domain filter-based algorithms,the proposed pilot of each transmitter can always be demodulated at the receiver even if the received pilots of multiple transmitters are totally overlapped.Although the channel state information is needed in designing the proposed pilot for carrier frequency offset(CFO)estimation,the performance of the proposed CFO estimation is robust to the channel estimation error.The optimal pilot as well as the Least-Squares(LS)channel estimator is also proposed,and the pilot for channel estimation is always a constant-modulus.A joint frequency offset and channel estimation scheme is also proposed,and the transmitters can adaptively optimize their pilots in the successive transmissions using the estimation results feedback in the former transmission.Simulation results demonstrate the performance of the proposed algorithm in terms of frequency offset and channel estimation accuracies.Since multiple copies of the same information can be received at each receiver,some combining technologies such as equal gain combining(EGC)or maximal ratio combining(MRC)can be applied at the receiver to improve the receiving diversity gain.Numerical results show that in a scenario of two transmitters with a Signal-to-Noise Ratio of 20 dB,the Bit Error Rate(BER)of1.5×10-4(or 1×10-4)can be obtained at the receiver using EGC(or MRC),and this BER performance can be improved to be 4×10-6for EGC(or 2×10-6for MRC)by considering three co-receiver transmitters.LI Yang XU Xu ZHANG DanDan ZHANG ZhongShan LONG KePing 2014Science China(Information Sciences)2014,57,4:5
10p-RWBO:a novel low-collision and QoS-supported MAC for wireless ad hoc networks显示文摘QoS supported MAC mechanism is a key issue for supporting QoS in wireless ad hoc networks. A new backoff algorithm,named RWBO+BEB,was proposed previously to decrease the packet collision probability significantly. In this paper,it is explored how to make RWBO+BEB support service differentiation in wireless ad hoc networks,and a novel proportional service differentiation algorithm,named p-RWBO,is proposed to allocate the wireless bandwidth according to the bandwidth ratio of each station. In p-RWBO,station n's walking probability(pw,n) is selected according to its allocated bandwidth ratio. An analytical model is proposed to analyze how to choose pw,n according to the bandwidth ratios of station n. The simulation results indicate that p-RWBO can differentiate services in terms of both bandwidth and delay.LONG KePing LI Yun ZHAO WeiLiang WANG ChongGang Kazem SOHRABY 2008Science in China(Series F)2008,51,9:4
11Pancreatic cancer显示文摘Donghui Li Keping Xie Robert Wolff James L Abbruzzese 2004The Lancet . 2004 (9414)2004,,:3
12Early positive effects of tree species richness on soil organic carbon accumulation in a large-scale forest biodiversity experiment显示文摘Aims tree species richness has been reported to have positive effects on aboveground biomass and productivity,but little is known about its effects on soil organic carbon(SOC)accumulation.Methods to close this gap,we made use of a large biodiversity-ecosystem functioning experiment in subtropical china(BEF-china)and tested whether tree species richness enhanced SOC accumulation.In 2010 and 2015,vertically layered soil samples were taken to a depth of 30 cm from 57 plots ranging in tree species richness from one to eight species.Least squares-based linear models and analysis of variance were used to investigate tree diversity effects.Structural equation modeling was used to explore hypothesized indirect relationships between tree species richness,leaf-litter biomass,leaf-litter carbon content,fine-root biomass and SOC accumulation.Important Findings Overall,SOC content decreased by 5.7 and 1.1 g C kg^(-1) in the top 0-5 and 5-10 cm soil depth,respectively,but increased by 1.0 and 1.5 g C kg^(-1) in the deeper 10-20 and 20-30 cm soil depth,respect-ively.converting SOC content to SOC stocks using measures of soil bulk density showed that tree species richness did enhance SOC accumulation in the different soil depths.these effects could only to some extent be explained by leaf-litter biomass and not by fine-root biomass.Our findings suggest that carbon storage in new forests in china could be increased by planting more diverse stands,with the potential to contribute to mitigation of climate warming.Yin Li Helge Bruelheide Thomas Scholten Bernhard Schmid Zhenkai Sun Naili Zhang Wensheng Bu Xiaojuan Liu Keping Ma 2019Journal of Plant Ecology2019,12,5:3
13Pancreatic cancer显示文摘Donghui Li Keping Xie Robert Wolff James L Abbruzzese 20042004 (9414)2004,,9414:3
14Pancreatic cancer显示文摘Donghui Li Keping Xie Robert Wolff James L Abbruzzese 2004The Lancet2004,,9414:2
15Development and Evaluation of a Wearable Lower Limb Rehabilitation Robot显示文摘This paper introduces a rigid-flexible coupling wearable exoskeleton robot for lower limb,which is designed in light of gait biomechanics and beneficial for low limb movement disorders by implementing gait training.The rationality of the proposed mechanism is shown with the implementation of the dynamic simulation through MSC ADAMS.For the purposes of lightweight,the exoskeleton mechanism is optimized through finite element analysis.It can be concluded from performance evaluation experiment,the mechanism has certain advantages over existing exoskeleton robots,namely,comfortable,lightweight,low cost,which can be utilized for rehabilitation training in medical institutions or as a daily-walking ancillary equipment for patients.Wanting Li Keping Liu Chunxu Li Zhongbo Sun Shui Liu Jian Gu 2022Journal of Bionic Engineering2022,19,3:2
16Compensatory effects between Pinus massoniana and broadleaved tree species显示文摘Aims Evaluation of the interaction intensity between Masson pine(Pinus massoniana)and broadleaved trees will facilitate selecting tree combinations suitable for reforestation in abandoned sites in subtropical areas.Methods Pinus massoniana and seven broadleaved trees species were grown either in monoculture or in two-species mixture.Biomass of tree species was measured and inter-specific interactions were estimated using log response ratio.Test of homogeneity of variances was performed to compare the stability of biomass in the monoculture of the broadleaved trees with that in the mixture.Important Findings Our results showed that the direction and intensity of interactions between P.massoniana and the broadleaved trees varied from year to year and the identity of the broadleaved species.Facilitative interactions were found between Camellia oleifera,Rhus chinensis and P.massoniana.Pinus massoniana had competitive effects on Lithocarpus glaber,Cyclobalanopsis glauca and Elaeocarpus japonicus.Significantly negative relations were found between biomass of P.massoniana and the broadleaved trees in the third year of the experiment,and the compensatory effects between P.massoniana and the broadleaved trees may be involved in stability maintenance in the multi-species forests in the subtropical area.The results of homogeneity test of variances also showed that the biomass per pot in the mixture had significantly lower variances than that in the monoculture,suggesting that total biomass is more stable in the mixture than the monoculture.Qian Li Yu Liang Bo Tong Xiaojun Du Keping Ma 2010Journal of Plant Ecology2010,3,3:2
17Challenge-based collaborative intrusion detection in software-defined networking: An evaluation显示文摘Software-Defined Networking(SDN)is an emerging architecture that enables a computer network to be intelligently and centrally controlled via software applications.It can help manage the whole network environment in a consistent and holistic way,without the need of understanding the underlying network structure.At present,SDN may face many challenges like insider attacks,i.e.,the centralized control plane would be attacked by malicious underlying devices and switches.To protect the security of SDN,effective detection approaches are indispensable.In the literature,challenge-based collaborative intrusion detection networks(CIDNs)are an effective detection framework in identifying malicious nodes.It calculates the nodes'reputation and detects a malicious node by sending out a special message called a challenge.In this work,we devise a challenge-based CIDN in SDN and measure its performance against malicious internal nodes.Our results demonstrate that such a mechanism can be effective in SDN environments.Wenjuan Li Yu Wang Zhiping Jin Keping Yu Jin Li Yang Xiang 2021Digital Communications and Networks2021,7,2:2
18A load balancing multi-path routing scheme based on effective voids for optical burst switching networks显示文摘Multi-path routing in the optical burst switching(OBS) networks can reduce the burst loss probability(BLP) by distributing the data burst traffic to multiple paths, compared with single path routing. Unlike the other multi-path routing schemes without considering the carrying capability of the routes, a new multi-path routing scheme based on effective voids(MPEV) is proposed to balance the load of multi-path and reduce the BLP in the paper. MPEV scheme first obtains the information on effective voids of the bottleneck link of multipath by sending a probe packet periodically. The effective voids can accommodate data bursts and accurately represent the available channel resource that is the main determinant of the BLP for OBS networks without optical random access memory. Then MPEV scheme distributes the burst traffic between an ingress node and an egress node to multiple link-disjoint paths by the ratio of the effective voids. More traffic is distributed to the path that has more effective voids, and vice versa. And the distributed amount is proportional to the effective voids of the bottleneck link. So MPEV scheme can balance the load of multi-path routes and can effectively reduce the BLP by avoiding the high load of a single path. And it is easy to implement and agilely adapt to dynamic network traffic. The performance of MPEV scheme is analyzed by queuing theory and is evaluated by simulation. The numerical results show that the proposed scheme can effectively reduce the BLP and balance the traffic load over multiple paths at the same time.HUANG Sheng ZHANG YunShui SUN Li Qin YANG XiaoLong LONG KePing 2015Science China(Information Sciences)2015,58,2:2
19Positioning taxonomic research for the future显示文摘Why do taxonomists matter? The work of taxonomists is often understated if not completely misunderstood. Without taxonomists, organisms cannot be accurately identified, neither can these organisms be given universally accepted names, and reliably positioned in the phylogenetic tree of life. Thanks to the work of taxonomists over the last 269 years since Carl Linnaeus established the binomial system, we can now measure the health and wealth of our biodiversity in a refined, science-based inventory prescribed by stringent nomenclatural rules.Deyuan Hong Wenying Zhuang Min Zhu Keping Ma Xiaoquan Wang Dawei Huang Yalin Zhang Guodong Ren Wenjun Bu Wanzhi Cai Dong Ren Ding Yang Aiping Liang Fengyan Bai Runzhi Zhang Fumin Lei Shuqiang Li Hongzhi Kong Lei Cai Yucheng Dai Chaodong Zhu Qisen Yang Jun Chen Zhongli Sha Jianping Jiang Jing Che Donghui Wu Jiatang Li Qiang Wang Xinli Wei Ming Bai Xingyue Liu Xuexin Chen Gexia Qiao 2022Zoological Systematics2022,47,3:2
20A semi-wet technological process for flue gas desulfurization by coro- na discharges at an industrial scale 显示文摘Yan Keping Li Ruinian Zhu Tianle 2006Chemical Engi- neering Journal2006,,2:1
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