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技术创新的系统动因分析及对策
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作者 袁明鹏 谢科范 《武汉汽车工业大学学报》 CAS 2000年第4期56-59,共4页
分析了影响企业技术创新的内在动因和外在动因及其关联关系 ,指出了外在动因对我国技术创新的重要作用 ,提出了改善外在动因 ,促进企业技术创新的基本思路。
关键词 技术创新 系统动因 企业 关联分析
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基于蚁群优化的作业成本动因选择方法研究 被引量:1
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作者 张绪 陆再林 +1 位作者 朱泽飞 李仁旺 《计算机仿真》 CSCD 北大核心 2009年第11期299-303,共5页
蚁群优化算法已成功地应用于复杂优化问题的求解,但其在生产成本管理领域的应用还是一个新的研究课题。本文针对作业成本管理(ABCM)中的成本动因的选择问题,建立了基于蚁群优化算法的成本动因的模型,并提出了一种基于蚁群优化算法的成... 蚁群优化算法已成功地应用于复杂优化问题的求解,但其在生产成本管理领域的应用还是一个新的研究课题。本文针对作业成本管理(ABCM)中的成本动因的选择问题,建立了基于蚁群优化算法的成本动因的模型,并提出了一种基于蚁群优化算法的成本动因选择的方法体系。最后设计了一个成本动因选择系统,有效解决了作业成本动因难于选择的问题,充分发挥了利用作业成本管理达到降低成本、合理使用资源与提升利润的作用。 展开更多
关键词 蚁群优化算法 作业成本动因 成本动因选择系统
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素质教育的系统论视域
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作者 伦畅 《科技咨询导报》 2007年第4期238-238,共1页
素质教育的实施有着系统性的动因,它不是单一因素造成的;从系统的角度理解素质教育才能树立科学的素质教育观,也只有从系统的角度才能全面查找阻碍其实施的因素,并在此基础上制定出解决问题的办法。
关键词 素质教育 系统动因 系统特征 阻碍因素
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实现网络教育中情感目标的研究 被引量:1
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作者 胡家双 孙文妮 《软件导刊.教育技术》 2010年第4期39-41,共3页
网络教育作为教育系统中一种新的教育形式,有着积极的一面也有着消极的一面,在网络教育中情感目标的缺失就是教育界的一大担忧。通过情感定义,找出网络教育中情感目标实现的动因,并启动情感动因系统。设想运用系统产生的动力来推动情感... 网络教育作为教育系统中一种新的教育形式,有着积极的一面也有着消极的一面,在网络教育中情感目标的缺失就是教育界的一大担忧。通过情感定义,找出网络教育中情感目标实现的动因,并启动情感动因系统。设想运用系统产生的动力来推动情感目标的实现,也为网络教育中情感目标的实现问题寻找另一个解决的角度。 展开更多
关键词 网络教育 情感目标 情感动因 动因系统
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Overview and Graph Theory of the Immune System of Crustacean 被引量:1
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作者 马寨璞 张繁霜 井爱芹 《Agricultural Science & Technology》 CAS 2010年第8期19-23,38,共6页
In this paper,different kinds of enzymes,immune factors and regulatory factors of the immune system of crustaceans are summarized and then combed systematically and thoroughly. According to the mutual influence and ef... In this paper,different kinds of enzymes,immune factors and regulatory factors of the immune system of crustaceans are summarized and then combed systematically and thoroughly. According to the mutual influence and effects of these factors,different symbolic forms are introduced to express the effects,and ultimately the whole node graph of the system is obtained. The graph theory can be used for further researches on the immune system of crustacean. 展开更多
关键词 CRUSTACEAN Immune system Immune factors Graph theory
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新型农业社会化服务体系构建探讨——以河南省为例 被引量:2
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作者 陈赟龙 潘经强 《科技创业月刊》 2013年第1期22-24,共3页
基于农业社会化服务体系的现状及主要问题,分析了新型农业社会化服务体系的系统动因,以河南省为例,探索从改革、重组公益性农业社会化服务机构、加大基层农技推广服务体系基础设施建设、多元化主体、践行"7R"服务等路径构建... 基于农业社会化服务体系的现状及主要问题,分析了新型农业社会化服务体系的系统动因,以河南省为例,探索从改革、重组公益性农业社会化服务机构、加大基层农技推广服务体系基础设施建设、多元化主体、践行"7R"服务等路径构建新型农业社会化服务体系。 展开更多
关键词 新型农业社会化服务 河南 系统动因 多元主体
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Regulated Gene Expression with Promoters Responding to Inducers 被引量:1
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作者 罗晓艳 唐巍 Vanessa Samuels 《Developmental and Reproductive Biology》 2002年第1期37-52,共16页
Genetically engineered transgenic animals and plants have proven to be extremely useful for analyzing biochemical and developmental processes.Promoters responding to chemical inducers will be powerful tools for basic ... Genetically engineered transgenic animals and plants have proven to be extremely useful for analyzing biochemical and developmental processes.Promoters responding to chemical inducers will be powerful tools for basic research in molecular biology and biotechnological applications.Various chemical inducible systems based on activation and inactivation of the target gene had been described.The transfer of regulatory elements from prokaryotes,insects,and mammals has opened new avenues to construct chemically inducible promoters that differ in their ability to regulate the temporal and spatial expression patterns,and this will dramatically increase the application of transgenic technology.This review provides an overview on regulation of gene expression,promoter activating systems,promoter inactivation systems,inducible gene over expression,and inducible anti suppression. 展开更多
关键词 regulated gene expression inducible promoter systems gene over expression and anti suppression
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Integrating Factors and Conservation Theorems of Nonholonomic Dynamical System of Relative Motion 被引量:2
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作者 QIAO Yong-Fen ZHAO Shu-Hong LI Ren-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期217-220,共4页
The integrating factors and conservation theorems of nonholonomic dynamical system of relative motion are studied. First, the dynamical equations of relative motion of system are written. Next, the definition of integ... The integrating factors and conservation theorems of nonholonomic dynamical system of relative motion are studied. First, the dynamical equations of relative motion of system are written. Next, the definition of integrating factors is given, and the necessary conditions for the existence of the conserved quantities are studied in detail. Then, the conservation theorem and its inverse of system are established. Finally, an example is given to illustrate the application of the result. 展开更多
关键词 nonholonomic system relative motion integrating factor conservation theorem
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Fuzzy control on automatic frequency tracking of ultrasonic vibration system with high power and high quality factor Q 被引量:4
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作者 朱武 张佳民 +2 位作者 刘洪利 孟逢逢 张智明 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第2期275-278,共4页
In order to realize automatic tracking drift of resonance frequency of ultrasonic vibration system with high power and high quality factor Q, adaptive fuzzy control was studied with a self-fabricated ultrasonic plasti... In order to realize automatic tracking drift of resonance frequency of ultrasonic vibration system with high power and high quality factor Q, adaptive fuzzy control was studied with a self-fabricated ultrasonic plastic welding machine. At first, relations between amplitude of vibration and frequency as well as main loop current and amplitude of vibration were analyzed. From this analysis, we deduced that frequency tracking process of the vibration system can be concluded as an optimizing problem of one dimensional fluctuant extremum of main loop current in vibration system. Then a method of self-optimizing fuzzy control, used for the realization of automatic frequency tracking in vibration system, is presented on the basis of serf-optimizing adaptive control approach and fuzzy control approach. The result of experiments shows that the fuzzy self-optimizing method can solve the problem of tracking frequency drift very well. Response time of tracking in the system is less than 50 ms, which basically meets the requirements of frequency tracking in ultrasonic plastic welding machine. 展开更多
关键词 automatic frequency tracking fuzzy control ultrasonic vibration system resonant frequency
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Changes in Ecosystem Service of Soil Conservation Between 2000 and 2010 and Its Driving Factors in Southwestern China 被引量:17
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作者 RAO Enming XIAO Yi +1 位作者 OUYANG Zhiyun ZHENG Hua 《Chinese Geographical Science》 SCIE CSCD 2016年第2期165-173,共9页
Human activities significantly alter ecosystems and their services; however, quantifying the impact of human activities on ecosystems has been a great challenge in ecosystem management. We used the Universal Soil Loss... Human activities significantly alter ecosystems and their services; however, quantifying the impact of human activities on ecosystems has been a great challenge in ecosystem management. We used the Universal Soil Loss Equation and county-level socioeconomic data to assess the changes in the ecosystem service of soil conservation between 2000 and 2010, and to analyze its spatial characteristics and driving factors in the southwestern China. The results showed that cropland in the southwestern China decreased by 3.74%, while urban land, forest, and grassland areas increased by 46.78%, 0.86%, and 1.12%, respectively. The soil conservation increased by 1.88 × 10^(11) kg, with deterioration only in some local areas. The improved and the degraded areas accounted for 6.41% and 2.44% of the total land area, respectively. Implementation of the Sloping Land Conversion Program and urbanization explained 57.80% and 23.90% of the variation in the soil conservation change, respectively, and were found to be the main factors enhancing soil conservation. The 2008 Wenchuan earthquake was one of the factors that led to the degradation of soil conservation. Furthermore, industrial adjustment, by increasing shares of Industry and Service and reducing those of Agriculture, has also promoted soil conservation. Our results quantitatively showed and emphasized the contributions to soil conservation improvement made by implementing ecological restoration programs and promoting urbanization. Consequently, these results provide basic information to improve our understanding of the effects of ecological restoration programs, and help guide future sustainable urban development and regional industrial restructuring. 展开更多
关键词 soil conservation ecosystem service Sloping Land Conversion Program(SLCP) ecological restoration urbanization southwestern China
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A brief review on the strategy for selection of orthology prediction methods in phylogenomic studies
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作者 吴昊阳 刘阳 +1 位作者 谢强 卜文俊 《Entomotaxonomia》 CSCD 北大核心 2012年第2期81-88,共8页
With the development and decreasing cost of sequencing techniques, it is possible for scientists to conduct deeper research in phylogenomics. During the procedure of phylogenomic analysis, the mostimportant and vitale... With the development and decreasing cost of sequencing techniques, it is possible for scientists to conduct deeper research in phylogenomics. During the procedure of phylogenomic analysis, the mostimportant and vitalest step is orthology prediction, for that the prerequisite to phylogenetic reconstruction is that the genes being compared are orthologous. Here we briefly review the related concept of orthology anddifferent methods for orthology prediction. We also provide recommendations to give some advice for better selection of orthology prediction methods. 展开更多
关键词 orthologous genes automatic tools tree-reconciliation phylogenetic reconstruction evolutionarystudy
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Research of Communication Mechanism of the Multi-agent in Multi-agent Robot Systems
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作者 高志军 Yan +4 位作者 Guozheng Ding Guoqing Huang Heng 《High Technology Letters》 EI CAS 2002年第1期67-71,共5页
The cooperation of multi-robot that is based on the multi-agent system (MAS) theory of distributed artificial intelligence has become a hotspot in the robotics R&D. In the research the multi-robot is regarded as m... The cooperation of multi-robot that is based on the multi-agent system (MAS) theory of distributed artificial intelligence has become a hotspot in the robotics R&D. In the research the multi-robot is regarded as multi-agent. So the communication and cooperation of multi-agent become the key problem for gaining the dynamic running information of cooperating robots. In this paper the authors introduce the communication modes for agent and provide a common strategy which aims at the communication resources of multi-agent model-the CSMA/CD (Carrier Sense Multiple Access with Collision Detection) protocol which is based on the transmittal medium. It supports the cable-communication of multi-robot and the experiments prove its validity. 展开更多
关键词 MAS CSMA/CD MULTI-AGENT
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Visualization of bHLH transcription factor interactions in living mammalian cell nuclei and developing chicken neural tube by FRET 被引量:1
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作者 Chen Wang Wei Bian +3 位作者 Caihong Xia Ting Zhang Francois Guillemot Naihe Jing 《Cell Research》 SCIE CAS CSCD 2006年第6期585-598,共14页
Members of the basic helix-loop-helix (bHLH) gene family play important roles in vertebrate neurogenesis. In this study, confocal microscopy-based fluorescence resonance energy transfer (FRET) is used to monitor b... Members of the basic helix-loop-helix (bHLH) gene family play important roles in vertebrate neurogenesis. In this study, confocal microscopy-based fluorescence resonance energy transfer (FRET) is used to monitor bHLH protein-protein interactions under various physiological conditions. Tissue-specific bHLH activators, NeuroD 1, Mash 1, Neurogenin 1 (Ngn 1), Neurogenin2 (Ngn2), and ubiquitous expressed E47 protein are tagged with enhanced yellow fluorescence protein (EYFP) and enhanced cyan fluorescence protein (ECFP), respectively. The subcellular localization and mobility ofbHLH fusion proteins are examined in HEK293 cells. By transient transfection and in ovo electroporation, four pairs of tissue-specific bHLH activators and E47 protein are over-expressed in HEK293 cells and developing chick embryo neural tube. With the acceptor photobleaching method, FRET could be detected between these bHLH protein pairs in the nuclei of transfected cells and developing neural tubes. Mashl/E47 and Ngn2/E47 FRET pairs show higher FRET efficiencies in the medial and the lateral half of chick embryo neural tube, respectively. It suggests that these bHLH protein pairs formed functional DNA-protein complexes with regulatory elements of their downstream target genes in the specific regions. This work will help one understand the behaviours of bHLH factors in vivo. 展开更多
关键词 BHLH confocal microscopy chick embryo neural tube FRET in ovo electroporation photobleach
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AGVs Dispatching Using Multiple Cooperative Learning Agents
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作者 李晓萌 YangYupu 《High Technology Letters》 EI CAS 2002年第3期83-87,共5页
AGVs dispatching, one of the hot problems in FMS, has attracted widespread interest in recent years. It is hard to dynamically schedule AGVs with pre designed rule because of the uncertainty and dynamic nature of AGVs... AGVs dispatching, one of the hot problems in FMS, has attracted widespread interest in recent years. It is hard to dynamically schedule AGVs with pre designed rule because of the uncertainty and dynamic nature of AGVs dispatching progress, so the AGVs system in this paper is treated as a cooperative learning multiagent system, in which each agent adopts multilevel decision method, which includes two level decisions: the option level and the action level. On the option level, an agent learns a policy to execute a subtask with the best response to the other AGVs’ current options. On the action level, an agent learns an optimal policy of actions for achieving his planned option. The method is applied to a AGVs’ dispatching simulation, and the performance of the AGVs system based on this method is verified. 展开更多
关键词 multi agent reinforcement learning multilevel decision AGVs dispatching
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Positively selected genes of the Chinese tree shrew (Tupaia belangeri chinensis) locomotion system 被引量:2
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作者 Yu FAN Dan-Dan YU Yong-Gang YAO 《Zoological Research》 CAS CSCD 北大核心 2014年第3期240-248,共9页
While the recent release of the Chinese tree shrew (Tupaia belangeri chinensis) genome has made the tree shrew an increasingly viable experimental animal model for biomedical research, further study of the genome ma... While the recent release of the Chinese tree shrew (Tupaia belangeri chinensis) genome has made the tree shrew an increasingly viable experimental animal model for biomedical research, further study of the genome may facilitate new insights into the applicability of this model. For example, though the tree shrew has a rapid rate of speed and strong jumping ability, there are limited studies on its locomotion ability. In this study we used the available Chinese tree shrew genome information and compared the evolutionary pattern of 407 locomotion system related orthologs among five mammals (human, rhesus monkey, mouse, rat and dog) and the Chinese tree shrew. Our analyses identified 29 genes with significantly high co (Ka/Ks ratio) values and 48 amino acid sites in 14 genes showed significant evidence of positive selection in the Chinese tree shrew. Some of these positively selected genes, e.g. HOXA6 (homeobox A6) and AVP (arginine vasopressin), play important roles in muscle contraction or skeletal morphogenesis. These results provide important clues in understanding the genetic bases of locomotor adaptation in the Chinese tree shrew. 展开更多
关键词 Chinese tree shrew Locomotion system Positively selected genes
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Irritable bowel syndrome:Diagnosis and pathogenesis 被引量:51
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作者 Magdy El-Salhy 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第37期5151-5163,共13页
Irritable bowel syndrome (IBS) is a common gastro-intestinal (GI) disorder that considerably reduces the quality of life. It further represents an economic burden on society due to the high consumption of healthcare r... Irritable bowel syndrome (IBS) is a common gastro-intestinal (GI) disorder that considerably reduces the quality of life. It further represents an economic burden on society due to the high consumption of healthcare resources and the non-productivity of IBS patients. The diagnosis of IBS is based on symptom assessment and the Rome Ⅲ criteria. A combination of the Rome Ⅲ criteria, a physical examination, blood tests, gastros-copy and colonoscopy with biopsies is believed to be necessary for diagnosis. Duodenal chromogranin A cell density is a promising biomarker for the diagnosis of IBS. The pathogenesis of IBS seems to be multifactorial, with the following factors playing a central role in the pathogenesis of IBS:heritability and genetics, dietary/intestinal microbiota, low-grade inflammation, and disturbances in the neuroendocrine system (NES) of the gut. One hypothesis proposes that the cause of IBS is an altered NES, which would cause abnormal GI motility, secretions and sensation. All of these abnormalities are characteristic of IBS. Alterations in the NES could be the result of one or more of the following:genetic factors, dietary intake, intestinal flora, or lowgrade inflammation. Post-infectious IBS (PI-IBS) and inflammatory bowel disease-associated IBS (IBD-IBS) represent a considerable subset of IBS cases. Patients with PI-and IBD-IBS exhibit low-grade mucosal inflammation, as well as abnormalities in the NES of the gut. 展开更多
关键词 CHOLECYSTOKININ Chromogranin A Diagno-sis DIET Endocrine cells Intestinal flora HEREDITARY Low-grade inflammation Peptide YY SEROTONIN
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Mesenteric Ischemia:An unusual presentation of fistula between superior mesenteric artery and common hepatic artery 被引量:1
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作者 Ertugrul Kayacetin Serdar Karakse +1 位作者 Aydin Karabacakoglu Dilek Emlik 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第17期2605-2606,共2页
Chronic mesenteric ischemia is an uncommon condition associated with a high morbidity and mortality.We reported a 36-year old women with postprandial abdominal pain due to chronic mesenteric ischemia caused by a fistu... Chronic mesenteric ischemia is an uncommon condition associated with a high morbidity and mortality.We reported a 36-year old women with postprandial abdominal pain due to chronic mesenteric ischemia caused by a fistula between superior mesenteric and common hepatic artery. 展开更多
关键词 ADULT ANGIOGRAPHY Arterio-Arterial Fistula FEMALE Hepatic Artery Humans ISCHEMIA Mesenteric Artery Superior
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Driving Forces and Their Effects on Water Conservation Services in Forest Ecosystems in China 被引量:11
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作者 GONG Shihan XIAO Yang +2 位作者 XIAO Yi ZHANG Lu OUYANG Zhiyun 《Chinese Geographical Science》 SCIE CSCD 2017年第2期216-228,共13页
Identifying the driving forces that cause changes in forest ecosystem services related to water conservation is essential for the design of interventions that could enhance positive impacts as well as minimizing negat... Identifying the driving forces that cause changes in forest ecosystem services related to water conservation is essential for the design of interventions that could enhance positive impacts as well as minimizing negative impacts. In this study, we propose an assessment concept framework model for indirect-direct-ecosystem service (IN-DI-ESS) driving forces within this context and method for index construction that considers the selection of a robust and parsimonious variable set. Factor analysis was integrated into two-stage data envelopment analysis (TS-DEA) to determine the driving forces and their effects on water conservation services in forest ecosystems at the provincial scale in China. The results showed the following. 1) Ten indicators with factor scores more than 0.8 were selected as the minimum data set. Four indicators comprising population density, per capita gross domestic product, irrigation efficiency, and per capita food consumption were the indirect driving factors, and six indicators comprising precipitation, farmland into forestry or pasture, forest cover, habitat area, water footprint, and wood extraction were the direct driving forces. 2) Spearman's rank correlation test was performed to compare the overall effectiveness in two periods: stage 1 and stage 2. The calculated coefficients were 0.245, 0.136, and 0.579, respectively, whereas the tabulated value was 0.562. This indicates that the driving forces obviously differed in terms of their contribution to the overall effectiveness and they caused changes in water conservation services in different stages. In terms of the variations in different driving force effects in the years 2000 and 2010, the overall, stage 1, and stage 2 variances were 0.020, 0.065, and 0.079 in 2000, respectively, and 0.018, 0.063, and 0.071 in 2010. This also indicates that heterogeneous driving force effects were obvious in the process during the same period. Identifying the driving forces that affect service changes and evaluating their efficiency have significant policy implications for the management of forest ecosystem services. Advanced effectiveness measures for weak regions could be improved in an appropriate manner. In this study, we showed that factor analysis coupled with TS-DEA based on the IN-D1-ESS framework can increase the parsimony of driving force indicators, as well as interpreting the interactions among indirect and direct driving forces with forest ecosystem water conservation services, and reducing the uncertainty related to the internal consistency during data selection. 展开更多
关键词 driving effectiveness driving force factor analysis forest ecosystem two-stage data envelopment analysis water conservation service
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Characterization of Chiton Ischnochiton hakodadensis Foot Based on Transcriptome Sequencing
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作者 DOU Huaiqian MIAO Yan +7 位作者 LI Yuli LI Yangping DAI Xiaoting ZHANG Xiaokang LIANG Pengyu LIU Weizhi WANG Shi BAO Zhenmin 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期632-640,共9页
Chiton(Ischnochiton hakodadensis) is one of marine mollusks well known for its eight separate shell plates. I. hakodadensis is important, which plays a vital role in the ecosystems it inhabits. So far, the genetic stu... Chiton(Ischnochiton hakodadensis) is one of marine mollusks well known for its eight separate shell plates. I. hakodadensis is important, which plays a vital role in the ecosystems it inhabits. So far, the genetic studies on the chiton are scarce due in part to insufficient genomic resources available for this species. In this study, we investigated the transcriptome of the chiton foot using Illumina sequencing technology. The reads were assembled and clustered into 256461 unigenes, of which 42247 were divided into diverse functional categories by Gene Ontology(GO) annotation terms, and 17256 mapped onto 365 pathways by KEGG pathway mapping. Meanwhile, a set of differentially expressed genes(DEGs) between distal and proximal muscles were identified as the foot adhesive locomotion associated, thus were useful for our future studies. Moreover, up to 679384 high-quality single nucleotide polymorphisms(SNPs) and 19814 simple sequence repeats(SSRs) were identified in this study, which are valuable for subsequent studies on genetic diversity and variation. The transcriptomic resource obtained in this study should aid to future genetic and genomic studies of chiton. 展开更多
关键词 CHITON transcriptome sequencing DEG SNP SSR
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A dynamic knowledge base based search engine
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作者 王会进 胡华 李清 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第7期683-688,共6页
Search engines have greatly helped us to find the desired information from the Internet. Most search engines use keywords matching technique. This paper discusses a Dynamic Knowledge Base based Search Engine (DKBSE)... Search engines have greatly helped us to find the desired information from the Internet. Most search engines use keywords matching technique. This paper discusses a Dynamic Knowledge Base based Search Engine (DKBSE), which can expand the user's query using the keywords' concept or meaning. To do this, the DKBSE needs to construct and maintain the knowledge base dynamically via the system's searching results and the user's feedback information. The DKBSE expands the user's initial query using the knowledge base, and returns the searched information after the expanded query. 展开更多
关键词 Dynamic knowledge base Query expansion Information retrieval Search engine
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