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Adaptive multicascade attribute reduction based on quantum-inspired mixed co-evolution
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作者 丁卫平 王建东 +1 位作者 施佺 管致锦 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期145-150,共6页
Due to the fact that conventional heuristic attribute reduction algorithms are poor in running efficiency and difficult in accomplishing the co-evolutionary reduction mechanism in the decision table, an adaptive multi... Due to the fact that conventional heuristic attribute reduction algorithms are poor in running efficiency and difficult in accomplishing the co-evolutionary reduction mechanism in the decision table, an adaptive multicascade attribute reduction algorithm based on quantum-inspired mixed co-evolution is proposed. First, a novel and efficient self- adaptive quantum rotation angle strategy is designed to direct the participating populations to mutual adaptive evolution and to accelerate convergence speed. Then, a multicascade model of cooperative and competitive mixed co-evolution is adopted to decompose the evolutionary attribute species into subpopulations according to their historical performance records, which can increase the diversity of subpopulations and select some elitist individuals so as to strengthen the sharing ability of their searching experience. So the global optimization reduction set can be obtained quickly. The experimental results show that, compared with the existing algorithms, the proposed algorithm can achieve a higher performance for attribute reduction, and it can be considered as a more competitive heuristic algorithm on the efficiency and accuracy of minimum attribute reduction. 展开更多
关键词 attribute reduction mixed co-evolution self- adaptive quantum rotation angle performance experience record elitist competition pool
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Triple-Helix Structured Model Based on Problem-Knowledge-Solution Co-evolution for Innovative Product Design Process 被引量:4
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作者 Qian Hui Yan Li +1 位作者 Ye Tao Hongwei Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第6期49-63,共15页
A design problem with deficient information is generally described as wicked or ill-defined.The information insufficiency leaves designers with loose settings,free environments,and a lack of strict boundaries,which pr... A design problem with deficient information is generally described as wicked or ill-defined.The information insufficiency leaves designers with loose settings,free environments,and a lack of strict boundaries,which provides them with more opportunities to facilitate innovation.Therefore,to capture the opportunity behind the uncertainty of a design problem,this study models an innovative design as a composite solving process,where the problem is clarified and resolved from fuzziness to satisfying solutions by interplay among design problems,knowledge,and solutions.Additionally,a triple-helix structured model for the innovative product design process is proposed based on the co-evolution of the problem,solution,and knowledge spaces,to provide designers with a distinct design strategy and method for innovative design.The three spaces interact and co-evolve through iterative mappings,including problem structuring,knowledge expansion,and solution generation.The mappings carry the information processing and decision-making activities of the design,and create the path to satisfying solutions.Finally,a case study of a reactor coolant flow distribution device is presented to demonstrate the practicability of this model and the method for innovative product design. 展开更多
关键词 Innovative design Problem-knowledge-solution co-evolution Design activity Design process Product design
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Cooperative co-evolution based distributed path planning of multiple mobile robots 被引量:3
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作者 王梅 吴铁军 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期697-706,共10页
This paper proposes novel multiple-mobile-robot collision avoidance path planning based on cooperative co-evolution,which can be executed fully distributed and in parallel. A real valued co-evolutionary algorithm is d... This paper proposes novel multiple-mobile-robot collision avoidance path planning based on cooperative co-evolution,which can be executed fully distributed and in parallel. A real valued co-evolutionary algorithm is developed to coordinate the movement of multiple robots in 2D world, avoiding C-space or grid net searching. The collision avoidance is achieved by cooperatively co-evolving segments of paths and the time interval to pass them. Methods for constraint handling, which are developed for evolutionary algorithm, make the path planning easier. The effectiveness of the algorithm is demonstrated on a number of 2Dpath planning problems. 展开更多
关键词 Cooperative co-evolution Multiple mobile robot Cooperative collision avoidance Path planning
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Harmony search algorithm with differential evolution based control parameter co-evolution and its application in chemical process dynamic optimization 被引量:1
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作者 范勤勤 王循华 颜学峰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2227-2237,共11页
A modified harmony search algorithm with co-evolutional control parameters(DEHS), applied through differential evolution optimization, is proposed. In DEHS, two control parameters, i.e., harmony memory considering rat... A modified harmony search algorithm with co-evolutional control parameters(DEHS), applied through differential evolution optimization, is proposed. In DEHS, two control parameters, i.e., harmony memory considering rate and pitch adjusting rate, are encoded as a symbiotic individual of an original individual(i.e., harmony vector). Harmony search operators are applied to evolving the original population. DE is applied to co-evolving the symbiotic population based on feedback information from the original population. Thus, with the evolution of the original population in DEHS, the symbiotic population is dynamically and self-adaptively adjusted, and real-time optimum control parameters are obtained. The proposed DEHS algorithm has been applied to various benchmark functions and two typical dynamic optimization problems. The experimental results show that the performance of the proposed algorithm is better than that of other HS variants. Satisfactory results are obtained in the application. 展开更多
关键词 harmony search differential evolution optimization co-evolution self-adaptive control parameter dynamic optimization
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Adaptive co-evolution of strategies and network leading to optimal cooperation level in spatial prisoner's dilemma game
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作者 陈含爽 侯中怀 +1 位作者 张季谦 辛厚文 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期25-30,共6页
We study evolutionary prisoner's dilemma game on adaptive networks where a population of players co-evolves with their interaction networks. During the co-evolution process, interacted players with opposite strategie... We study evolutionary prisoner's dilemma game on adaptive networks where a population of players co-evolves with their interaction networks. During the co-evolution process, interacted players with opposite strategies either rewire the link between them with probability p or update their strategies with probability 1 - p depending on their payoffs. Numerical simulation shows that the final network is either split into some disconnected communities whose players share the same strategy within each community or forms a single connected network in which all nodes are in the same strategy. Interestingly, the density of cooperators in the final state can be maximised in an intermediate range of p via the competition between time scale of the network dynamics and that of the node dynamics. Finally, the mean-field analysis helps to understand the results of numerical simulation. Our results may provide some insight into understanding the emergence of cooperation in the real situation where the individuals' behaviour and their relationship adaptively co-evolve. 展开更多
关键词 prisoner's dilemma game adaptive network co-evolution COOPERATION
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Pathogenetic Consequences of Cytomegalovirus-Host Co-evolution
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作者 Gerardo Abenes 《Virologica Sinica》 SCIE CAS CSCD 2008年第6期438-448,共11页
Co-evolution has been shown to result in an adaptive reciprocal modification in the respective behaviors of interacting populations over time. In the case of host-parasite co-evolution,the adaptive behavior is most ev... Co-evolution has been shown to result in an adaptive reciprocal modification in the respective behaviors of interacting populations over time. In the case of host-parasite co-evolution,the adaptive behavior is most evident from the reciprocal change in fitness of host and parasite-manifested in terms of pathogen survival versus host resistance. Cytomegaloviruses and their hosts represent a pairing of populations that has co-evolved over hundreds of years. This review explores the pathogenetic consequences emerging from the behavioral changes caused by co-evolutionary forces on the virus and its host. 展开更多
关键词 CYTOMEGALOVIRUS co-evolution PATHOGENESIS
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Adaptive Co-evolution Model for Multi-agent System
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作者 张向锋 丁永生 梁朝霞 《Journal of Donghua University(English Edition)》 EI CAS 2010年第2期123-126,共4页
It is important to harmonize effectively the behaviors of the agents in the multi-agent system (MAS) to complete the solution process. The co-evolution computing techniques, inspired by natural selection and genetics,... It is important to harmonize effectively the behaviors of the agents in the multi-agent system (MAS) to complete the solution process. The co-evolution computing techniques, inspired by natural selection and genetics, are usually used to solve these problems. Based on learning and evolution mechanisms of the biological systems, an adaptive co-evolution model was proposed in this paper. Inner-population, inter-population, and community learning operators were presented. The adaptive co-evolution algorithm (ACEA) was designed in detail. Some simulation experiments were done to evaluate the performance of the ACEA. The results show that the ACEA is more effective and feasible than the genetic algorithm to solve the optimization problems. 展开更多
关键词 adaptive co-evolution algorithm multi-agent system LEARNING EVOLUTION genetic algorithm
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A cooperative Co-evolutional immune algorithm
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作者 刘丽珏 Cai Zixing 《High Technology Letters》 EI CAS 2009年第2期126-130,共5页
A co-evolutional immune algorithm for the optimization of a function with real parameters is de-scribed.It uses a cooperative co-evolution of two populations,one is a population of antibodies and theother is a populat... A co-evolutional immune algorithm for the optimization of a function with real parameters is de-scribed.It uses a cooperative co-evolution of two populations,one is a population of antibodies and theother is a population of successful mutation vectors.These two population evolve together to improve thediversity of the antibodies.The algorithm described is then tested on a suite of optimization problems.The results show that on most of test functions,this algorithm can converge to the global optimum atquicker rate in a given range,the performance of optimization is improved effetely. 展开更多
关键词 IMMUNITY co-evolution CLONE MUTATION optimization real-parameter
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A Co-Evolution Model for Dynamic Social Network and Behavior
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作者 Liping Tong David Shoham Richard S. Cooper 《Open Journal of Statistics》 2014年第9期765-775,共11页
Individual behaviors, such as drinking, smoking, screen time, and physical activity, can be strongly influenced by the behavior of friends. At the same time, the choice of friends can be influenced by shared behaviora... Individual behaviors, such as drinking, smoking, screen time, and physical activity, can be strongly influenced by the behavior of friends. At the same time, the choice of friends can be influenced by shared behavioral preferences. The actor-based stochastic models (ABSM) are developed to study the interdependence of social networks and behavior. These methods are efficient and useful for analysis of discrete behaviors, such as drinking and smoking;however, since the behavior evolution function is in an exponential format, the ABSM can generate inconsistent and unrealistic results when the behavior variable is continuous or has a large range, such as hours of television watched or body mass index. To more realistically model continuous behavior variables, we propose a co-evolution process based on a linear model which is consistent over time and has an intuitive interpretation. In the simulation study, we applied the expectation maximization (EM) and Markov chain Monte Carlo (MCMC) algorithms to find the maximum likelihood estimate (MLE) of parameter values. Additionally, we show that our assumptions are reasonable using data from the National Longitudinal Study of Adolescent Health (Add Health). 展开更多
关键词 SOCIAL Network SOCIAL BEHAVIOR co-evolution MARKOV CHAIN STATIONARY Distribution
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Hybrid Support Vector Regression with Parallel Co-Evolution Algorithm Based on GA and PSO for Forecasting Monthly Rainfall
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作者 Jiansheng Wu Yongsheng Xie 《Journal of Software Engineering and Applications》 2019年第12期524-539,共16页
Accurate and timely monthly rainfall forecasting is a major challenge for the scientific community in hydrological research such as river management project and design of flood warning systems. Support Vector Regressi... Accurate and timely monthly rainfall forecasting is a major challenge for the scientific community in hydrological research such as river management project and design of flood warning systems. Support Vector Regression (SVR) is a very useful precipitation prediction model. In this paper, a novel parallel co-evolution algorithm is presented to determine the appropriate parameters of the SVR in rainfall prediction based on parallel co-evolution by hybrid Genetic Algorithm and Particle Swarm Optimization algorithm, namely SVRGAPSO, for monthly rainfall prediction. The framework of the parallel co-evolutionary algorithm is to iterate two GA and PSO populations simultaneously, which is a mechanism for information exchange between GA and PSO populations to overcome premature local optimum. Our methodology adopts a hybrid PSO and GA for the optimal parameters of SVR by parallel co-evolving. The proposed technique is applied over rainfall forecasting to test its generalization capability as well as to make comparative evaluations with the several competing techniques, such as the other alternative methods, namely SVRPSO (SVR with PSO), SVRGA (SVR with GA), and SVR model. The empirical results indicate that the SVRGAPSO results have a superior generalization capability with the lowest prediction error values in rainfall forecasting. The SVRGAPSO can significantly improve the rainfall forecasting accuracy. Therefore, the SVRGAPSO model is a promising alternative for rainfall forecasting. 展开更多
关键词 Genetic ALGORITHM Particle Swarm Optimization RAINFALL Forecasting PARALLEL co-evolution
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Demand-side Response Strategy of Multi-microgrids Based on an Improved Co-evolution Algorithm 被引量:2
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作者 Yang Gao Qian Ai 《CSEE Journal of Power and Energy Systems》 SCIE CSCD 2021年第5期903-910,共8页
An effective modeling and optimization method,which takes into account source-load-storage coordination,and full-time collaborative optimization within and outside micro-grids,is introduced.Considering the operational... An effective modeling and optimization method,which takes into account source-load-storage coordination,and full-time collaborative optimization within and outside micro-grids,is introduced.Considering the operational conditions of various resources and their interactions,an energy management model for microgrids is proposed aiming at maximization of renewable energy utilization and minimization of overall system costs.The model is suitable for both real-time pricing and time-of-use mechanisms.In microgrids,demand response and economic energy storage dispatch are introduced to enhance selfcoordination and self-balancing ability among different resources.Depending on whether there is still an imbalance between supply and demand after coordination within a niicrogrid,trade between it and external microgrids are optimized in a orderly manner by considering different transaction prices and usage rights.Finally,three different schemes are designed,where the Lagrangian multiplier method as well as a co-evolution algorithm are used to solve and analyze different examples,verifying the reliability and validity of the method proposed in this paper. 展开更多
关键词 Terms—co-evolution demand-side response multi-microgrids source-load-storage coordination.
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Co-evolution:A New Perspective for Business Model Innovation 被引量:1
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作者 Yi YU Yimei HU +1 位作者 Han QIAO Shouyang WANG 《Journal of Systems Science and Information》 CSCD 2018年第5期385-398,共14页
This paper combines the perspective of co-evolution with studies in the area of business model, reveals the phenomenon of business model co-evolution and explores the business model coevolution mechanism between firms... This paper combines the perspective of co-evolution with studies in the area of business model, reveals the phenomenon of business model co-evolution and explores the business model coevolution mechanism between firms through a case study. Findings and what other companies can learn from this study are as follows. Firstly, companies, be it leaders or not, can act as enablers for other party’s business model innovation. Secondly, companies can enable each other’s business model innovation by taking the perspective of business model co-evolution; Thirdly, the interdependence of the business model co-evolution process can be explained by the four levers named novelty, lock-in,complementarity and efficiency. Companies can select novelty, lock-in, complementarity, efficiency or the combination of the four as mediators to achieve business model co-evolution. 展开更多
关键词 business model innovation co-evolution business model ice-berg theory television media
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Asymmetric or diffusive co-evolution generates meta-populations in fig-fig wasp mutualisms
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作者 WANG RuiWu YANG Yan WIGGINS Natasha L. 《Science China(Life Sciences)》 SCIE CAS 2014年第6期596-602,共7页
Co-evolutionary theory assumes co-adapted characteristics are a positive response to counter those of another species,whereby co-evolved species reach an evolutionarily stable interaction through bilateral adaptation.... Co-evolutionary theory assumes co-adapted characteristics are a positive response to counter those of another species,whereby co-evolved species reach an evolutionarily stable interaction through bilateral adaptation.However,evidence from the fig-fig wasp mutualistic system implies very different co-evolutionary selection mechanisms,due to the inherent conflict among interacted partners.Fig plants appear to have discriminatively enforced fig wasps to evolve"adaptation characteristics"that provide greater benefit to the fig,and fig wasps appear to have diversified their evolutionary strategies in response to discriminative enforcement by figs and competition among different fig wasp species.In what appears to be an asymmetric interaction,the prosperity of cooperative pollinating wasps should inevitably lead to population increases of parasitic individuals,thus resulting in localized extinctions of pollinating wasps.In response,the sanctioning of parasitic wasps by the fig should lead to a reduction in the parasitic wasp population.The meta-populations created by such asymmetric interactions may result in each population of coevolved species chaotically oscillated,temporally or evolutionarily. 展开更多
关键词 asymmetric co-evolution inter-specific cooperation META-POPULATION MUTUALISM
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The Evolution Relationship with Supplies: a Study Based on Co-evolution
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作者 Yuhong Xin 《Journal of Systems Science and Information》 2007年第3期321-326,共6页
The traditionary point considers the stratagem relationship of SCP (supply chain partnership) which can be strengthened mutual relationship with supplies by holding the same stratagem to enhances performance of supp... The traditionary point considers the stratagem relationship of SCP (supply chain partnership) which can be strengthened mutual relationship with supplies by holding the same stratagem to enhances performance of supply chain management. At present, many scholars have studied this relationship more and more, but much papers are not satisfyingly explain complex relationship with supplies. Because the more complex and the more dynamic the market changes, the more flexile the custom demand. So the tradition point faces new challenge, which relationship with supplies not only has the same stratagem based on long-profit but also has more flexile for adapting demand of market. In this paper, we use theory of biology and complex adaptive system (CAS), points out the new relationship model called co-evolution relationship of SCP. 展开更多
关键词 supply chain partnership co-evolution relationship copmlex adaptive system
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Pocket Modification of x-Amine Transaminase AtATA for Overcoming the Trade-Off Between Activity and Stability Toward 1-Acetonaphthone
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作者 Jiaren Cao Fangfang Fan +6 位作者 Changjiang Lyu Sheng Hu Weirui Zhao Jiaqi Mei Shuai Qiu Lehe Mei Jun Huang 《Engineering》 SCIE EI CAS CSCD 2023年第11期203-214,共12页
Amine transaminases(ATAs)catalyze the asymmetric amination of prochiral ketones or aldehydes to their corresponding chiral amines.However,the trade-off between activity and stability in enzyme engineering represents a... Amine transaminases(ATAs)catalyze the asymmetric amination of prochiral ketones or aldehydes to their corresponding chiral amines.However,the trade-off between activity and stability in enzyme engineering represents a major obstacle to the practical application of ATAs.Overcoming this trade-off is important for developing robustly engineered enzymes and a universal approach for ATAs.Herein,we modified the binding pocket of co-ATA from Aspergillus terreus(AtATA)to identify the key amino acid residues controlling the activity and stability of AtATA toward 1-acetonaphthone.We discovered a structural switch comprising four key amino acid sites(R128,V149,L182,and L187),as well as the"best"mutant(AtATAD224K/V149A/L182 F/L187F;termed M4).Compared to the parent enzyme AtATAD224K(AtATAPa),M4 increased the catalytic efficiency(k_(cat)/K_(m)^(1-acetonaphthone),where kcatis the constant of catalytic activities and is 10.1 min^(-1),K_(m)^(1-acetonaphthoneis) Michaelis-Menten constant and is 1.7 mmol·L^(-1))and half-life(t1/2)by 59-fold to 5.9 L·min^(-1)·mmol-1and by 1.6-fold to 46.9 min,respectively.Moreover,using M4 as the biocatalyst,we converted a 20 mmol·L^(-1)aliquot of 1-acetonaphthone in a 50 mL scaled-up system to the desired product,(R)-(+)-1(1-naphthyl)ethylamine((R)-NEA),with 78%yield and high enantiomeric purity(R>99.5%)within 10 h.M4 also displayed significantly enhanced activity toward various 1-acetonaphthone analogs.The related structural properties derived by analyzing structure and sequence information of robust ATAs illustrated their enhanced activity and thermostability.Strengthening of intramolecular interactions and expansion of the angle between the substratebinding pocket and the pyridoxal 5’-phosphate(PLP)-binding pocket contributed to synchronous enhancement of ATA thermostability and activity.Moreover,this pocket engineering strategy successfully transferred enhanced activity and thermostability to three other ATAs,which exhibited 8%-22%sequence similarity with AtATA.This research has important implications for overcoming the trade-off between ATA activity and thermostability. 展开更多
关键词 Trade-off co-evolution Amine transaminase (R)-(+)-1(1-naphthyl)ethylamine
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Diversity of Sucking Lice on Small Mammals in the Surrounding Areas of Erhai Lake in Yunnan,China 被引量:3
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作者 董文鸽 郭宪国 +2 位作者 门兴元 钱体军 吴滇 《Entomotaxonomia》 CSCD 北大核心 2009年第1期68-80,共13页
An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004. From investigation sites, 3 303 small mammal hosts were c... An investigation of sucking lice on the body surface of small mammals was carried out in the surrounding areas of Erhai Lake in Dali, Yunnan from 2003 to 2004. From investigation sites, 3 303 small mammal hosts were captured and identified into 7 families, 15 genera and 21 species in 4 orders (Rodentia, Insectivora, Scandentia and Carnivora), while t4 635 individuals of sucking lice collected from the body surface of the small mammal hosts are identified into 5 families, 6 genera and 21 species in the Order Anoplura, The sites stand alongside three cordilleras surrounding the Erhai Lake, namely Eastern Wuliang Mountain, Southern Ailao Mountain and Western Cangshan Mountain. The three confined oriented areas are different landscapes within the same zone where the longitude, latitude, altitude and fauna are homologous but isolated by Erhai Lake as inartificial barrier. The aim of this study was to recognize features of the species diversity, abundance, community structure, similarity and distribution of sucking lice in different landscapes within the same zone. The results showed the species diversity of sucking lice was very low with a very simple community structure. The distribution of sucking lice and their corresponding hosts are quite uneven among different oriented areas and this may imply that ecological environment influences the species composition and distribution of sucking lice and their corresponding hosts. A certain species of hosts usually have their fixed louse species. The similarity of sucking louse communities is highly consistent with the affinity of small mammal hosts in taxonomy. Species of sucking lice on the same small mammal host in different oriented areas of Erhai Lake are homologous. The results strongly suggest a close relationship of co-evolution between sucking lice and their hosts. 展开更多
关键词 ANOPLURA small mammal species diversity community ecology co-evolution.
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The arms race between Magnaporthe oryzae and rice: Diversity and interaction of Avr and R genes 被引量:44
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作者 WANG Bao-hua Daniel J.Ebbole WANG Zong-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第12期2746-2760,共15页
Rice blast disease, caused by Magnaporthe oryzae, threatens global food security. The rice blast pathosystem is a longstanding model system for understanding plant-microbe interactions. In order to elucidate the coevo... Rice blast disease, caused by Magnaporthe oryzae, threatens global food security. The rice blast pathosystem is a longstanding model system for understanding plant-microbe interactions. In order to elucidate the coevolution of the host and pathogen, and provide the appropriate methods for preventing or controlling rice blast disease, researchers have focused on the evolution of virulence factors and resistance genes. Thus far, more than 30 rice blast resistance(R) genes and 12 avirulence(Avr) genes have been cloned. This review summarizes the cloned rice blast R genes, cloned Avr genes of M. oryzae and the interaction between them. This discussion also considers some of the major unanswered questions concerning this pathosystem and the opportunities for future investigations. 展开更多
关键词 RICE Maganporthe oryzae resistance gene avirulence gene co-evolution genetic diversity
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Helicobacter pylori in human health and disease:Mechanisms for local gastric and systemic effects 被引量:38
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作者 Denisse Bravo Anilei Hoare +2 位作者 Cristopher Soto Manuel A Valenzuela Andrew FG Quest 《World Journal of Gastroenterology》 SCIE CAS 2018年第28期3071-3089,共19页
Helicobacter pylori(H. pylori) is present in roughly 50% of the human population worldwide and infection levels reach over 70% in developing countries. The infection has classically been associated with different gast... Helicobacter pylori(H. pylori) is present in roughly 50% of the human population worldwide and infection levels reach over 70% in developing countries. The infection has classically been associated with different gastro-intestinal diseases, but also with extra gastric diseases. Despite such associations, the bacterium frequently persists in the human host without inducing disease, and it has been suggested that H. pylori may also play a beneficial role in health. To understand how H. pylori can produce such diverse effects in the human host, several studies have focused on understanding the local and systemic effects triggered by this bacterium. One of the main mechanisms by which H. pylori is thought to damage the host is by inducing local and systemic inflammation. However, more recently, studies are beginning to focus on the effects of H. pylori and its metabolism on the gastric and intestinal microbiome. The objective of this review is to discuss how H. pylori has co-evolved with humans, how H. pylori presence is associated with positive and negative effects in human health and how inflammation and/or changes in the microbiome are associated with the observed outcomes. 展开更多
关键词 HELICOBACTER PYLORI co-evolution Extragastric diseases Inflammation MICROBIOME
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Characterization of a novel toxin-antitoxin module,VapBC,encoded by Leptospira interrogans chromosome 被引量:6
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作者 YiXuanZHANG XiaoKuiGUO +4 位作者 ChuanWU BoBI ShuangXiREN ChunFuWU GuoPingZHAO 《Cell Research》 SCIE CAS CSCD 2004年第3期208-216,共9页
Comparative genomic analysis of the coding sequences (CDSs) of Leptospira interrogans revealed a pair of closely linked genes homologous to the vapBC loci of many other bacteria with respect to both deduced amino acid... Comparative genomic analysis of the coding sequences (CDSs) of Leptospira interrogans revealed a pair of closely linked genes homologous to the vapBC loci of many other bacteria with respect to both deduced amino acid sequences and operon organizations. Expression of single vapC gene in Escherichia coli resulted in inhibition of bacterial growth,whereas co-expression of vapBC restored the growth effectively. This phenotype is typical for three other characterized toxin-antitoxin systems of bacteria, i.e., mazEF[1], relBE[2] and chpIK[3]. The VapC proteins of bacteria and a thermophilic archeae, Solfolobus tokodaii, form a structurally distinguished group of toxin different from the other known toxins of bacteria. Phylogenetic analysis of both toxins and antitoxins of all categories indicated that although toxins were evolved from divergent sources and may or may not follow their speciation paths (as indicated by their 16s RNA sequences), co-evolution with their antitoxins was obvious. 展开更多
关键词 Leptospria toxin-antitoxin system VapBC co-evolution speciation.
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Eco-spatial Structure of Urban Agglomeration 被引量:6
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作者 GUO Rongchao MIAO Changhong +1 位作者 LI Xuexin CHEN Deguang 《Chinese Geographical Science》 SCIE CSCD 2007年第1期28-33,共6页
In terms of ecological theory, this paper makes a comprehensive analysis of the mutualism and co- evolutionary mechanism between the eco-spatial structure and socio-economic development of the urban agglomeration, and... In terms of ecological theory, this paper makes a comprehensive analysis of the mutualism and co- evolutionary mechanism between the eco-spatial structure and socio-economic development of the urban agglomeration, and maps out optimized modes of the eco-spatial structure of the urban agglomeration. The analysis is a case study of the urban agglomeration on different levels of global, national, provincial and local scales, on the basis of those conclusions are drawn: 1) Within the scope of the urban agglomeration, the cities should be reasonably sized and appropriately densified; the spatial combination of the urban agglomeration ought to be orderly, and its eco-spatial structure ought to be optimized and efficient; the relationship between the economic society and eco-spatial environment ought to be that of mutual benefit and co-evolution. 2) “The mode of corridor group network” is a certain trend evoked from the spatial structure of urban agglomeration. 3) The eco-spatial structure of urban agglomeration under “the mode of corridor group network” can further increase the environmental capacity of urban agglomeration, and is in favor of the harmonious relationship between man and nature. 展开更多
关键词 mutualism theory co-evolution theory urban agglomeration eco-spatial structure corridor group network
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