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用于竞争性RT-PCR评估刚地弓形虫速殖子-缓殖子相互转换的多竞争体的构建与验证
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作者 朱翔 《国外医学(寄生虫病分册)》 2002年第5期234-235,共2页
刚地弓形虫感染中间宿主后几乎可以在所有组织内以速殖子形式快速增殖。宿主免疫功能正常时,宿主产生免疫力后,速殖子转变为缓殖子,在寄居部位形成包囊结构,长期存活。当宿主免疫功能降低时,包囊中缓殖子转变为速殖子,使疾病状态再现。
关键词 弓形虫感染 竞争性RT-PCR 刚地弓形虫 速殖子-缓殖子 多竞争 构建
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对抗WLAN系统OBSS频谱效率不足的MAC层设计
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作者 刘刚 郭秋瑾 +1 位作者 郭漪 杨世勇 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2017年第4期1-6,143,共7页
针对无线局域网系统中重叠基本服务集引起的频谱利用率不足问题,通过引入虚拟主信道,提出了两种基于竞争的媒体访问控制层设计方案,即传输机会方案和多竞争方案.传输机会方案基于长数据包传输,适用于有高吞吐量需求的应用,多竞争方案基... 针对无线局域网系统中重叠基本服务集引起的频谱利用率不足问题,通过引入虚拟主信道,提出了两种基于竞争的媒体访问控制层设计方案,即传输机会方案和多竞争方案.传输机会方案基于长数据包传输,适用于有高吞吐量需求的应用,多竞争方案基于短数据包传输,适用于要求短时延的业务.仿真结果表明,通过有效利用重叠基本服务集引起的未被充分利用的频谱资源,传输机会方案能够极大地提高网络吞吐量,多竞争方案则能够显著降低发送短数据包的延时. 展开更多
关键词 无线局域网 重叠基本服务集 虚拟主信道 传输机会 多竞争
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Competitive location problem of multi-level pickup point considering cooperative coverage 被引量:2
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作者 Han Xun Zhang Jin Zeng Qian 《Journal of Southeast University(English Edition)》 EI CAS 2019年第1期111-117,共7页
To occupy a greater market share in terminal distribution, companies are urged to make full use of cooperative coverage formed with brand effect and information sharing in the layout of pickup points. Based on the div... To occupy a greater market share in terminal distribution, companies are urged to make full use of cooperative coverage formed with brand effect and information sharing in the layout of pickup points. Based on the diversity of pickup points, the piecewise function, signal intensity function and probability function are introduced. Meanwhile, considering the effect of distance satisfaction and cooperation coverage on customer behavior, the location model of the pickup point under competitive environments is established. The genetic algorithm is used to solve the problem, and the effectiveness of the model and algorithm is verified by a case. The results show that the sensitivity of weighted demand coverages to budget decreases gradually. The maximum weighted demand coverage increases at first and then decreases with the increase of the signal threshold, and there is a positive correlation with the change of the actual demand coverage to the senior customers, but it is negatively related to the intermediate and primary customers. When the number of high-level pickup points in a competitive enterprise is small, the advantage of the target enterprise is more significant. Through comparison, the cooperative coverage model is better than the non-cooperative coverage model, in terms of the weighted demand coverage, the construction cost and the attention paid to the important customers. 展开更多
关键词 pickup point cooperative coverage multi-level facility layout competitive conditions genetic algorithm
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Rule-based scheduling of multi-stage multi-product batch plants with parallel units 被引量:2
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作者 Bin Shi Xinrui Qian +1 位作者 Shanshan Sun Liexiang Yan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第8期1022-1036,共15页
A novel rule-based model for multi-stage multi-product scheduling problem(MMSP)in batch plants with parallel units is proposed.The scheduling problem is decomposed into two sub-problems of order assignment and order s... A novel rule-based model for multi-stage multi-product scheduling problem(MMSP)in batch plants with parallel units is proposed.The scheduling problem is decomposed into two sub-problems of order assignment and order sequencing.Firstly,hierarchical scheduling strategy is presented for solving the former sub-problem,where the multi-stage multi-product batch process is divided into multiple sequentially connected single process stages,and then the production of orders are arranged in each single stage by using forward order assignment strategy and backward order assignment strategy respectively according to the feature of scheduling objective.Line-up competition algorithm(LCA)is presented to find out optimal order sequence and order assignment rule,which can minimize total flow time or maximize total weighted process time.Computational results show that the proposed approach can obtain better solutions than those of the literature for all scheduling problems with more than 10 orders.Moreover,with the problem size increasing,the solutions obtained by the proposed approach are improved remarkably.The proposed approach has the potential to solve large size MMSP. 展开更多
关键词 Line-up competition algorithm Order assignment role Multi-stage multi-product Parallel unit Scheduling optimization
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Economic management and innovation strategies of enterprises under market economy conditions
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作者 Qing LI 《International Journal of Technology Management》 2015年第3期19-21,共3页
Under the highly competitive market economy management system, economic management of Chinese enterprises tends to be diversity. With the continuous development of market economy, enterprises need choose the appropria... Under the highly competitive market economy management system, economic management of Chinese enterprises tends to be diversity. With the continuous development of market economy, enterprises need choose the appropriate management methods according to the actual situation, which is to help enterprises to survive in the highly competitive environment. However, due to a variety of external factors, economic management situation is not optimistic. And it increases their sense of crisis. This article will make a systematic analysis of management strategies as the point of the enterprise management mode and innovation strategy under market economy. 展开更多
关键词 market economy enterprise economy management strategy
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Facility Management in the Globalized Society
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作者 Bortosova Viera Valaskova Katarina 《Management Studies》 2018年第5期358-366,共9页
Facility management is the multi-disciplinary kind of work that covers a wide range of various activities, responsibilities, and knowledge. Facility management provides and manages a variety of support services in ord... Facility management is the multi-disciplinary kind of work that covers a wide range of various activities, responsibilities, and knowledge. Facility management provides and manages a variety of support services in order to prepare all the organisational functions, putting the accent on an integration of primary activities in strategic, tactical, and operational levels. In the final decade of the previous century, facility mmmgement industry emerged as one of the fastest growing sectors at the international level. Nowadays, the importance of the facility management is readily acknowledged in many companies worldwide, which recognises the necessity of properly managing elaborate and expensive support facilities. The tasks are multi-disciplinary and cover a wide range of activities, responsibilities, and knowledge, because every aspect of an organisation may come under the competency of the facility management. The main aim of the paper is to point out the well-founded applicability of the global facility management in companies, which in order to achieve the competitive advantage correctly strengthened the corporate core business and shift the support activities into the management of a specialist in this field. The paper also covers the scope of the facility management in the international context, and also in the Slovak Republic, considering the specificities of individual countries 展开更多
关键词 facility management support process corporate management GLOBALIZATION
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Qatar as an Emerging Islamic Finance Hub
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作者 Issam Tlemsani 《Journal of Modern Accounting and Auditing》 2015年第11期596-605,共10页
The principal objectives of this research are to provide information, commentary, and analysis of the potential opportunities for Qatar in developing its Islamic financial services and industry. This research examines... The principal objectives of this research are to provide information, commentary, and analysis of the potential opportunities for Qatar in developing its Islamic financial services and industry. This research examines how competitive Qatar is today and its future prospects in Islamic finance. This research provides policy makers and Islamic finance stakeholders with a superior understanding of the role of the key competitive factors in Islamic fmance. It is anticipated that this research will influence the growth and diversification of Islamic financial services in Qatar. 展开更多
关键词 Islamic finance financial competition Islamic financial services financial hub
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A network of sex and competition: The promiscuous mating system of an invasive weevil 被引量:4
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作者 Alberto Francesco INGHILESI Giuseppe MAZZA +1 位作者 Rita CERVO Alessandro CINI 《Current Zoology》 SCIE CAS CSCD 2015年第1期85-97,共13页
Invasive alien pest insect species represent a major threat for agriculture and biodiversity. Because chemical treatments employed to contrast such pests elicit serious environmental and human health problems, a great... Invasive alien pest insect species represent a major threat for agriculture and biodiversity. Because chemical treatments employed to contrast such pests elicit serious environmental and human health problems, a great effort is currently directed to develop long term and environmentally friendly biological control strategies. However, the successful application of some promising techniques, such as the Sterile Insect Technique (SIT), requires a deep knowledge of the pest basic biology. Here, we argue that understanding pest sexual biology using a social network approach can significantly improve the performance of con- trol strategies. For example, SIT may benefit from understanding how individuals interact and how males accede to reproduction, in order to target the most reproductively active and polygamic males. In this paper we studied the socio-sexual networks of the Asian red palm weevil (RPW) Rhynchophorusferrugineus, a worldwide invader which is causing heavy economic impacts on several palm species. We found that the RPW has a highly promiscuous mating system, characterized by forced interruptions of pair copulations by additional males. The social network is highly non-random nor regular: few males almost monopolize repro- duction, behaving as key-players in the network of matings. Additionally, males have a stable pattern of sexual behaviour over time. We use RPW social network as a case study to direct the development of management techniques such as SIT strategy [Current Zoology 61 (1): 85-97, 2015]. 展开更多
关键词 Social network analysis Pest management Mating system Reproductive skew Alien pest Rhynchophorusferrugineus
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Behavioral effects of social challenges and genomic mechanisms of social priming: What's testosterone got to do with it? 被引量:2
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作者 Kimberly A. ROSVALL Mark E PETERSON 《Current Zoology》 SCIE CAS CSCD 2014年第6期791-803,共13页
Social challenges from rival conspecifics are common in the lives of animals, and changes in an animal's social environment can influence physiology and behavior in ways that appear to be adaptive in the face of cont... Social challenges from rival conspecifics are common in the lives of animals, and changes in an animal's social environment can influence physiology and behavior in ways that appear to be adaptive in the face of continued social instability (i.e. social priming). Recently, it has become clear that testosterone, long thought to be the primary mediator of these effects, may not always change in response to social challenges, an observation that highlights gaps in our understanding of the proximate me- chanisms by which animals respond to their social environment. Here, our goal is to address the degree to which testosterone me- diates organismal responses to social cues. To this end, we review the behavioral and physiological consequences of social chal- lenges, as well as their underlying hormonal and gene regulatory mechanisms. We also present a new case study from a wild songbird, the dark-eyed junco Junco hyemalis, in which we find largely divergent genome-wide transcriptional changes induced by social challenges and testosterone, respectively, in muscle and liver tissue. Our review underscores the diversity of mechani- sms that link the dynamic social environment with an organisms' genomic, hormonal, and behavioral state. This diversity among species, and even among tissues within an organism, reveals new insights into the pattern and process by which evolution may alter proximate mechanisms of social priming. 展开更多
关键词 Social priming Challenge hypothesis AGGRESSION Hormonal mechanism TESTOSTERONE Genomics
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The Game Theoretical Approach for Multi-phase Complex Systems in Chemical Engineering 被引量:7
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作者 LI Yan MU Yifen +1 位作者 YUAN Shuo GUO Lei 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2017年第1期4-19,共16页
This paper explores the application of noncooperative game theory together with the concept of Nash equilibrium to the investigation of some basic problems on multi-scale structure, especially the meso-scale structure... This paper explores the application of noncooperative game theory together with the concept of Nash equilibrium to the investigation of some basic problems on multi-scale structure, especially the meso-scale structure in the multi-phase complex systems in chemical engineering. The basis of this work is the energy-minimization-multi-scale (EMMS) model proposed by Li and Kwauk (1994) and Li, et al. (2013) which identifies the multi-scale structure as a result of 'compromise-in-competition between dominant mechanisms' and tries to solve a multi-objective optimization problem. However, the existing methods often integrate it into a problem of single objective optimization, which does not clearly reflect the 'compromise-in-competition' mechanism and causes heavy computation burden as well as uncertainty in choosing suitable weighting factors. This paper will formulate the compromise in competition mechanism in EMMS model as a noncooperative game with constraints, and will describe the desired stable system state as a generalized Nash equilibrium. Then the authors will investigate the game theoretical approach for two typical systems in chemical engineering, the gas-solid fluidiza- tion (GSF) system and turbulent flow in pipe. Two different cases for generalized Nash equilibrinm in such systems will be well defined and distinguished. The generalize Nash equilibrium will be solved accurately for the GSF system and a feasible method will be given for turbulent flow in pipe. These results coincide with the existing computational results and show the feasibility of this approach, which overcomes the disadvantages of the existing methods and provides deep insight into the mechanisms of multi-scale structure in the multi-phase complex systems in chemical engineering. 展开更多
关键词 Game theory gas-solid fluidization generalized Nash equilibrium multi-phase complexsystems turbulent flow.
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Current plant diversity but not its soil legacy influences exotic plant invasion 被引量:3
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作者 Wei Xue Si-Mei Yao +3 位作者 Lin Huang Sergio RRoiloa Bao-Ming Ji Fei-Hai Yu 《Journal of Plant Ecology》 SCIE CSCD 2022年第3期639-649,共11页
Current plant diversity can influence exotic plant invasion,but it is unclear whether there is a legacy effect of plant diversity on exotic plant invasion.As plant diversity can affect soil microbial communities and p... Current plant diversity can influence exotic plant invasion,but it is unclear whether there is a legacy effect of plant diversity on exotic plant invasion.As plant diversity can affect soil microbial communities and physio-chemical properties,which may cascade to impact subsequent exotic plant growth,we hypothesize that the soil legacy effect of plant diversity can influence exotic plant invasion.We conducted a plant–soil feedback experiment.In the conditioning phase,we trained soils by monocultures of 12 plant species from three functional groups(4 grasses,3 legumes and 5 forbs)and mixtures of 8 randomly selected species with all three functional groups from this 12-species pool.In the test phase,we grew the invasive plant Bidens pilosa with a co-occurring native grass(Arthraxon hispidus),with a co-occurring native forb(Pterocypsela indica)or with both in each type of the conditioned soils.The performance of B.pilosa relative to its native competitors varied depending on the functional type of both conditioning plant species in the conditioning phase and competing plant species in the test phase.Diversity of the conditioning plants did not influence the growth difference between B.pilosa and its native competitors.However,increasing diversity of the competing plant species reduced the performance of B.pilosa relative to its native competitors.Our results suggest that current plant diversity can reduce exotic plant invasion through increasing growth inequality between invasive and native plants,but the soil legacy effect of plant diversity may have little impact on exotic plant invasion. 展开更多
关键词 Bidens pilosa competitive balance diversity effect invasive plant plant–soil feedback
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Avian succession along ecological gradients: Insight from species-poor and species-rich communities of Sylvia warblers
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作者 Alban GUILLAUMET Roger PRODON 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第3期307-317,共11页
The mechanisms responsible for species replacement during ecological successions is a long-standing and open debate. In this study, we examined the distribution of the Sardinian warbler Sylvia melanocephala along two ... The mechanisms responsible for species replacement during ecological successions is a long-standing and open debate. In this study, we examined the distribution of the Sardinian warbler Sylvia melanocephala along two grassland-to-forest gradients, one in a high-diversity area (Albera-Aspres chain in Catalonia: eight Sylvia warbler species) and one in a low-diversity area (Mount Hymittos in Greece: four species). In Catalonia, distribution models suggested that the apparent exclusion of S. melanocephala from the open and forest ends of the gradient may be explained entirely by the preference of S. melanocephala for mid-successional shrublands. However, a joint analysis of both data sets revealed that: 1) S. melanocephala was more evenly dis- tributed along the vegetation gradient in Greece, suggesting ecological release in the low-diversity area; and 2) a distribution model assuming interspecific competition (based on the distribution of Sylvia species showing a negative co-occurrence pattern with S. melanocephala) had a significantly higher predictive ability than a distribution model based on habitat variables alone. Our study supports the view that species turnover along ecological gradients generally results from a combination of intrinsic preferences and interspecific competition [Current Zoology 57 (3): 307-317, 2011]. 展开更多
关键词 Avian succession Cross-validation Diffuse competition Ecological release GLM Habitat selection Nichewidening Species distribution model
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Inducible competitors and adaptive diversification
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作者 Beren W. ROBINSON David W. PFENNIG 《Current Zoology》 SCIE CAS CSCD 2013年第4期537-552,共16页
Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and... Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and the formation of new spe- cies-stems from divergent natural selection, often arising from competitive interactions. Although increasing evidence suggests that phenotypic plasticity can facilitate this process, it is not generally appreciated that competitively mediated selection often also provides ideal conditions for phenotypic plasticity to evolve in the first place. Here, we discuss how competition plays at least two key roles in adaptive diversification depending on its pattern. First, heterogenous competition initially generates heterogeneity in resource use that favors adaptive plasticity in the form of "inducible competitors". Second, once such competitively induced plas- ticity evolves, its capacity to rapidly generate phenotypic variation and expose phenotypes to alternate selective regimes allows populations to respond readily to selection favoring diversification, as may occur when competition generates steady diversifying selection that permanently drives the evolutionary divergence of populations that use different resources. Thus, competition plays two important roles in adaptive diversification---one well-known and the other only now emerging--mediated through its effect on the evolution ofphenotypic plasticity 展开更多
关键词 Phenotypic plasticity COMPETITION Adaptive radiation Character displacement Genetic assimilation Resourcepolymorphism
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