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Temperature modifies activity, inter-individual relationships and group structure in a fish 被引量:2
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作者 Tatiana COLCHEN Fabrice TELETCHEA +1 位作者 Pascal FONTAINE Alain PASQUET 《Current Zoology》 SCIE CAS CSCD 2017年第2期175-183,共9页
A host of abiotic factors modify fish social behavior. However, few studies have characterized the effects of temperature on behavior. In this study, brown trout Salmo trutta fry were reared at 5 dif- ferent temperatu... A host of abiotic factors modify fish social behavior. However, few studies have characterized the effects of temperature on behavior. In this study, brown trout Salmo trutta fry were reared at 5 dif- ferent temperatures (4℃, 6℃, 8℃, 10℃, and 12℃). In order to characterize group structure, 3 be- havioral parameters were investigated: group social structure (based on inter-individual distances), inter-individual relationships (based on physical contacts), and individual activity. These behavioral parameters were studied at the emergence stage, which corresponds to a switch from a social gre- garious life in the gravel to a solitary one in the water column. Data analysis showed that the inter- individual distances increased with increasing temperature, particularly the nearest neighbor distance. The mean number of physical contacts between fry increased at both low and high tem- peratures. At high temperatures, most fry moved apart from each other after a physical contact. Swimming activity decreased at both the lower and upper temperatures (18% of activity at 4℃, 38% at 8℃, and 12% at 12℃). This study showed that temperature modifies brown trout fry activity, inter-individual relationships, and social behavior, which all affect group cohesion before emer- gence and can influence their survival and dispersal. 展开更多
关键词 early development EMERGENCE freshwater species group structure relationships.
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Evaluation on Radar Reflectivity-Rainfall Rate (Z-R) Relationships for Guyana 被引量:3
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作者 Komalchand Dhiram Zhenhui Wang 《Atmospheric and Climate Sciences》 2016年第4期489-499,共12页
The constant development of science and technology in weather radar results in high-resolution spatial and temporal rainfall estimates and improved early warnings of meteorological phenomena such as flood [1]. Weather... The constant development of science and technology in weather radar results in high-resolution spatial and temporal rainfall estimates and improved early warnings of meteorological phenomena such as flood [1]. Weather radars do not measure the rainfall amount directly, so a relationship between the reflectivity (Z) and rainfall rate (R), called the Z-R relationship (Z = aR<sup>b</sup>), where a and b are empirical constants, can be used to estimate the rainfall amount. In this research, mathematical techniques were used to find the best climatological Z-R relationships for the Low Coastal Plain of Guyana. The reflectivity data from the S-Band Doppler Weather Radar for February 17 and 21, 2011 and May 8, 2012 together with the daily rainfall depths at 29 rainfall stations located within a 150 km radius were investigated. A climatological Z-R relationship type Z = 200R<sup>1.6</sup> (Marshall-Palmer) configured by default into the radar system was used to investigate the correlation between the radar reflectivity and the rainfall by gauges. The same data sets were used with two distinct experimental Z-R relationships, Z = 300R<sup>1.4</sup> (WSR-88D Convective) and Z = 250R<sup>1.2</sup> (Rosenfeld Tropical) to determine if any could be applicable for area of study. By comprehensive regression analysis, New Z-R and R-Z relationships for each of the three events aforementioned were developed. In addition, a combination of all the samples for all three events were used to produce another relationship called “All in One”. Statistical measures were then applied to detect BIAS and Error STD in order to produce more evidence-based results. It is proven that different Z-R relationships could be calibrated into the radar system to provide more accurate rainfall estimation. 展开更多
关键词 Radar Reflectivity Rain Gauges Rainfall Rate z-r relationships CORRELATION
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Understanding the Variability of Z-R Relationships Caused by Natural Variations in Raindrop Size Distributions(DSD):Implication of Drop Size and Number 被引量:1
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作者 Abe D.Ochou Eric-Pascal Zahiri +1 位作者 Bakary Bamba Manlandon Koffi 《Atmospheric and Climate Sciences》 2011年第3期147-164,共18页
In the issue of rainfall estimation by radar through the necessary relationship between radar reflectivity Z and rain rate R (Z-R), the main limitation is attributed to the variability of this relationship. Indeed, se... In the issue of rainfall estimation by radar through the necessary relationship between radar reflectivity Z and rain rate R (Z-R), the main limitation is attributed to the variability of this relationship. Indeed, several pre-vious studies have shown the great variability of this relationship in space and time, from a rainfall event to another and even within a single rainfall event. Recent studies have shown that the variability of raindrop size distributions and thereby Z-R relationships is therefore, more the result of complex dynamic, thermody-namic and microphysical processes within rainfall systems than a convective/stratiform classification of the ground rainfall signature. The raindrop number and size at ground being the resultant of various processes mentioned above, a suitable approach would be to analyze their variability in relation to that of Z-R relation-ship. In this study, we investigated the total raindrop concentration number NT and the median volume di-ameter D0 used in numerous studies, and have shown that the combination of these two ‘observed’ parame-ters appears to be an interesting approach to better understand the variability of the Z-R relationships in the rainfall events, without assuming a certain analytical raindrop size distribution model (exponential, gamma, or log-normal). The present study is based on the analysis of disdrometer data collected at different seasons and places in Africa, and aims to show the degree of the raindrop size and number implication in regard to the Z-R relationships variability. 展开更多
关键词 Raindrop Size Distribution Radar Reflectivity Factor Rain Rate Median Volume Diameter Total Number of Drops Per Unit Volume z-r relationship Convective Rain Stratiform Rain Squall Lines THUNDERSTORM
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Genetic Relationships among Prunus mume var. pendula Using AFLP Markers 被引量:3
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作者 Ming Jun Zhang Qixiang +3 位作者 Ru Guangxin Mao Qingshan Yan Xiaolan Lan Yanping 《Forestry Studies in China》 CAS 2003年第4期26-30,共5页
Genetic relationships among Prunus mume var. pendula were studied by using AFLP markers. 18 accessions representing 14 cultivars of Prunus mume var. pendula were selected from the germplasm collection at the Research ... Genetic relationships among Prunus mume var. pendula were studied by using AFLP markers. 18 accessions representing 14 cultivars of Prunus mume var. pendula were selected from the germplasm collection at the Research Center of China Mei Flower. Seven Mse I-EcoR I AFLP primer combinations revealed 450 legible bands, and 269 of which were polymorphic markers. A similarity matrix was prepared using the simple matching coefficient of similarity and Neis (72) distance coefficient. A UPGMA dendrogram demonstrated the genetic relationships of the cultivars. The information given by AFLP markers was basically consistent with the morphological classification and the evolutionary history of the morphotypes, and roughly supported the new revised classification system for Chinese Mei Cultivars. But there were still several exceptions: 1) the Guhong Chuizhi inserted between the Tiaoxue Chuizhi and the Danfen Chuizhi; 2) the Wufu Chuizhi kept off the Pink Pendant Form, and the Moshan Chuizhi was removed from Viridiflora Pendant Form; 3) the Danbi Chuizhi and the Shuangbi Chuizhi of Viridiflora Pendant Form got together well but fell within the Pink Pendant Form. 展开更多
关键词 Prunus mume Sieb. et Zucc. amplified fragment length polymorphism (AFLP) Prunus mume var. pendula (Pendulous Mei group) genetic relationship
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Consensus model of social network group decision-making based on trust relationship among experts and expert reliability 被引量:4
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作者 WANG Ya CAI Mei JIAN Xinglian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1576-1588,共13页
Due to people’s increasing dependence on social networks,it is essential to develop a consensus model considering not only their own factors but also the interaction between people.Both external trust relationship am... Due to people’s increasing dependence on social networks,it is essential to develop a consensus model considering not only their own factors but also the interaction between people.Both external trust relationship among experts and the internal reliability of experts are important factors in decision-making.This paper focuses on improving the scientificity and effectiveness of decision-making and presents a consensus model combining trust relationship among experts and expert reliability in social network group decision-making(SN-GDM).A concept named matching degree is proposed to measure expert reliability.Meanwhile,linguistic information is applied to manage the imprecise and vague information.Matching degree is expressed by a 2-tuple linguistic model,and experts’preferences are measured by a probabilistic linguistic term set(PLTS).Subsequently,a hybrid weight is explored to weigh experts’importance in a group.Then a consensus measure is introduced and a feedback mechanism is developed to produce some personalized recommendations with higher group consensus.Finally,a comparative example is provided to prove the scientificity and effectiveness of the proposed consensus model. 展开更多
关键词 social network group decision-making(SN-GDM) trust relationship expert reliability consensus model probabilistic linguistic term set(PLTS).
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THE RELATIONSHIP BETWEEN THE INVASION OF PARAPHARYNGEAL SPACES AND THE INVOLVEMENT OF CERVICAL NODES AND POSTERIOR GROUP CRANIAL NERVES IN NASOPHARYNGEAL CARCINOMA 被引量:1
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作者 卢泰祥 张恩罴 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1992年第1期65-70,共6页
Two hundred cates of nasopharyngeal carcinoma (NPC) admitted to this department from Feb. 1985 to May. 1988 were analysed according to the CT scanning and clinical findings of the primary lesions prior to radiotherapy... Two hundred cates of nasopharyngeal carcinoma (NPC) admitted to this department from Feb. 1985 to May. 1988 were analysed according to the CT scanning and clinical findings of the primary lesions prior to radiotherapy. The results showed that involvement of parapharyngeal space was very common in NPC, about 80% (160/200 cases) ; particularly unilateral or bilateral retro-styloid spaces, about 69.5% (139/200 cases). It was proposed that patients with NPC had a high Incidence of ipsilateral cervical node metastasis. Contralateral cervical node metastasis was rare. The development of cervical node metastasto in NPC has two modes: one Is direct Infiltration of the retro-stylold space by the lesion; the other Is along the nasopharyngeal lymphatic rete. The data also showed that patients with NPC who presented symptoms of Ⅸ- Ⅲ cranial nerve paralyses always had ipsilateral or bilateral retro- styloid space Infiltrations. 展开更多
关键词 NPC THE relationship BETWEEN THE INVASION OF PARAPHARYNGEAL SPACES AND THE INVOLVEMENT OF CERVICAL NODES AND POSTERIOR group CRANIAL NERVES IN NASOPHARYNGEAL CARCINOMA line
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A Large-Scale Group Decision Making Model Based on Trust Relationship and Social Network Updating
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作者 Rongrong Ren Luyang Su +2 位作者 Xinyu Meng Jianfang Wang Meng Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期429-458,共30页
With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that consid... With the development of big data and social computing,large-scale group decisionmaking(LGDM)is nowmerging with social networks.Using social network analysis(SNA),this study proposes an LGDM consensus model that considers the trust relationship among decisionmakers(DMs).In the process of consensusmeasurement:the social network is constructed according to the social relationship among DMs,and the Louvain method is introduced to classify social networks to form subgroups.In this study,the weights of each decision maker and each subgroup are computed by comprehensive network weights and trust weights.In the process of consensus improvement:A feedback mechanism with four identification and two direction rules is designed to guide the consensus of the improvement process.Based on the trust relationship among DMs,the preferences are modified,and the corresponding social network is updated to accelerate the consensus.Compared with the previous research,the proposedmodel not only allows the subgroups to be reconstructed and updated during the adjustment process,but also improves the accuracy of the adjustment by the feedbackmechanism.Finally,an example analysis is conducted to verify the effectiveness and flexibility of the proposed method.Moreover,compared with previous studies,the superiority of the proposed method in solving the LGDM problem is highlighted. 展开更多
关键词 Large-scale group decision making social network updating trust relationship group consensus feedback mechanism
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Exploring Application Layer Protocol Relationships in SoftSwitch
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作者 Zhu Xiaomin Liao Jianxin +1 位作者 Chen Junliang Li Tonghong 《China Communications》 SCIE CSCD 2009年第4期155-167,共13页
Relationships between application layer protocols in softswitch are explored in this paper.Two notions, i.e.protocol relationship and protocol grouping, are proposed, which are not clearly defined and even not paid mu... Relationships between application layer protocols in softswitch are explored in this paper.Two notions, i.e.protocol relationship and protocol grouping, are proposed, which are not clearly defined and even not paid much attention to before.On the basis of a well known protocol relationship named protocol conversion, three novel protocol relationships including protocol collaboration relationship, protocol cooperation relationship and protocol independent relationship are presented, so that protocol relationships are classified into four types.According to the functionality and purpose of each protocol, main protocols related to softswitch are divided into five groups.As to protocol conversion in softswitch, information flow trail(IFT) is utilized to facilitate problem solving.A decision rule for protocol conversion mode is proposed to guide how to choose between direct conversion and indirect conversion.A property of protocol relationships in softswitch is induced from all kinds of service scenarios of softswitch.This property summarizes protocol relationships within each protocol group or between two specific protocol groups.A merit of protocol grouping together with classification of protocol relationship is also presented.The effort of this paper pushes the protocol engineering to go ahead. 展开更多
关键词 protocol relationship protocol grouping SOFTSWITCH information flow trail
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Expression of Snail in bladder urothelial carcinoma and its relationship with E-cadherin and a subset of T cell groups
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作者 张墨 《外科研究与新技术》 2011年第4期247-247,共1页
Objective To investigate the expression of Snail in bladder urothelial carcinoma and evaluate its relationship with E-cadherin and a subset of T cell groups. Methods Immunohistochemical method was used to detect the e... Objective To investigate the expression of Snail in bladder urothelial carcinoma and evaluate its relationship with E-cadherin and a subset of T cell groups. Methods Immunohistochemical method was used to detect the expression of Snail and E-cadherin proteins in tissue 展开更多
关键词 Expression of Snail in bladder urothelial carcinoma and its relationship with E-cadherin and a subset of T cell groups cell
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变化环境下长江流域上下游水安全互馈关系研究
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作者 夏军 熊立华 +9 位作者 邹磊 常利伟 陈能成 陈进 魏荣菲 杨大文 王永强 张翔 佘敦先 程磊 《人民长江》 北大核心 2026年第1期1-11,共11页
随着全球变化,尤其长江干流城市群所联系的经济带建设与长江开发等高强度人类活动影响愈来愈凸显,长江流域水循环正在发生变化。深入解析流域水文循环与水环境演变机制及其驱动因素,对长江经济带绿色高质量发展和长江大保护具有重要意义... 随着全球变化,尤其长江干流城市群所联系的经济带建设与长江开发等高强度人类活动影响愈来愈凸显,长江流域水循环正在发生变化。深入解析流域水文循环与水环境演变机制及其驱动因素,对长江经济带绿色高质量发展和长江大保护具有重要意义。1980年以来,在气候变化与高强度人类活动双重胁迫下,长江流域水循环发生了显著变化。水库群调控重塑了径流过程,城市化则导致地表水文过程与水安全需求发生显著改变。在洪旱极端灾害条件下,长江流域上下游水安全形成了“调控-响应-反馈”复杂互馈关系。在此背景下,系统综述了水库群调控效应、城市群水文效应及流域水循环演变规律三方面的研究成果。研究表明:(1)水库群削丰补枯作用明显,显著改变了天然径流情势,但在未来极端事件频率升高条件下,其削峰作用可能减弱。(2)城市化导致不透水面积增加,引起了城市热岛、雨岛效应加剧,沿江城市群外洪与内涝防控矛盾增加。(3)在气候变化和城市人口增长共同影响下,城市群水资源安全保障压力不断增加,未来保障压力因预估的水资源增加和人口减少而在一定程度上缓解。研究成果可为长江流域“人-水-城”绿色发展和长江大保护提供科技支撑。 展开更多
关键词 水安全互馈关系 水库群调控 城市化 流域水循环 长江大保护 长江流域
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参照群体与社会关系的双重性——县域教师家长教育期望底层逻辑的一个社会学解释
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作者 董永贵 王倩兮 《当代教育与文化》 2026年第1期91-98,共8页
县域教育是乡村振兴的重要环节,承载着基础教育公平与质量提升的双重使命。县域教师家长的双重身份使其教育期望呈现独特样态。本研究通过对10组教师家长及其子女的半结构化访谈深入探究该议题。研究发现,县域教师家长的教育期望呈现“... 县域教育是乡村振兴的重要环节,承载着基础教育公平与质量提升的双重使命。县域教师家长的双重身份使其教育期望呈现独特样态。本研究通过对10组教师家长及其子女的半结构化访谈深入探究该议题。研究发现,县域教师家长的教育期望呈现“互为参照群体”的双重表征,其社会关系的双重性也使教育行动呈现双重性。其教育期望底层逻辑具体表现为互为参照群体下期许“别人家孩子”的隐形竞赛、道德凝视中“模范家庭”的自我规训与焦虑传导、地域性社会资本运作的优质资源攫取与信息利用、弱关系网络匮乏的体制执念偏好与眼界发展受限,以及亲子关系角色失调与情感耗竭的学业辅导困境。 展开更多
关键词 教育期望 县域教师家长 参照群体 社会关系
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基于云团的分组Z-R关系拟合方案效果评估与误差分析 被引量:10
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作者 勾亚彬 刘黎平 +2 位作者 王丹 仲凌志 陈超 《暴雨灾害》 2015年第1期1-8,共8页
为了降低因Z-R关系不确定导致的雷达定量降水估测(Quantitative Precipitation Estimation,简称QPE)误差,提出了基于云团的分组Z-R关系拟合方案,在风暴单体识别算法得到的不同降水云团或同一个云团内部的不同数据分组区域内,拟合并采用... 为了降低因Z-R关系不确定导致的雷达定量降水估测(Quantitative Precipitation Estimation,简称QPE)误差,提出了基于云团的分组Z-R关系拟合方案,在风暴单体识别算法得到的不同降水云团或同一个云团内部的不同数据分组区域内,拟合并采用不同的Z-R关系反演地面降水信息。以2013年6月5—7日的梅雨锋过程为例,使用覆盖长江中下游地区的28部多普勒雷达和全国逐分钟雨量计的观测资料,对单一动态关系、简单分组Z-R关系以及基于云团的分组ZR关系反演的雷达1 h QPE进行效果对比和误差分析,结果表明:(1)基于云团的分组Z-R关系可以有效识别降水云系的局部特征,这是基于云团的分组Z-R关系优于其他两种Z-R关系方案的重要原因。(2)雷达波束部分遮挡导致的偏弱反射率因子,对雷达QPE数据场的不连续性和Z-R关系的不确定性均有影响。(3)雷达硬件或雷达标定引入的偏强(弱)的反射率因子,与简单分组Z-R关系得到的雷达QPE局部高(低)估相关,这降低了简单分组Z-R关系在大范围降水过程中的适用性,但对基于云团的分组Z-R关系的影响较小。 展开更多
关键词 风暴单体识别 分组z-r关系 定量降水估测
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Information for Authors
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《Zoological Systematics》 2026年第1期84-84,共1页
The current journal is mainly focused in zoological systematics.According to Systematics Agenda 2000(1994),systematics is the science built on the following tasks:Taxonomy—the science of discovering,describing,and cl... The current journal is mainly focused in zoological systematics.According to Systematics Agenda 2000(1994),systematics is the science built on the following tasks:Taxonomy—the science of discovering,describing,and classifying species or groups of species(together termed taxa);Phylogenetic analysis—the discovery of the evolutionary relationships among a group of species;and Classification—the grouping of species,ultimately on the basis of evolutionary relationships. 展开更多
关键词 classification grouping speciesultimately zoological systematics taxa phylogenetic analysis zoological systematicsaccording TAXONOMY phylogenetic analysis evolutionary relationships
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基于动态分析的城市轨道交通线网安检研究
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作者 王洪臣 李亚南 《铁道运营技术》 2026年第1期47-50,共4页
随着网络化运营和出行客流量增加,轨道交通常态化安检受到广泛关注,为优化提升整体服务质量和运营管理效率,在系统梳理现状安检需求基础上,以多源信息融合、量化统计分析、分级灵活管理为依托,通过线网安检中心统一调配管控和任务部署,... 随着网络化运营和出行客流量增加,轨道交通常态化安检受到广泛关注,为优化提升整体服务质量和运营管理效率,在系统梳理现状安检需求基础上,以多源信息融合、量化统计分析、分级灵活管理为依托,通过线网安检中心统一调配管控和任务部署,研究实现与车站态势相匹配的安检模式,确保城市轨道交通线网安检的可视、可管、可控,同时提供安全、舒适、便捷的快速进站服务。 展开更多
关键词 数据增强 依赖关系 分类分级 群体模型 进站信息 象限客流
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Research on the Karyotype and Evolution of Drosophila melanogaster Species Group 被引量:1
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作者 Qiuhong Deng Qingtao Zeng +2 位作者 Yuanhuai Qian Chunxuan Li Yong Yang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第3期196-213,共18页
Mitotic metaphase chromosomes of 34 species of Drosophila melanogaster species group were examined.Certain new karyotypes were described for the first time,and their evolutionary and interspecific genetic relationship... Mitotic metaphase chromosomes of 34 species of Drosophila melanogaster species group were examined.Certain new karyotypes were described for the first time,and their evolutionary and interspecific genetic relationships among 8 subgroups of D.melanogaster species group were analyzed systematically.The results were as follows.The basic karyotype of elegans subgroup was type A.The karyotypes of eugracilis subgroup,melanogaster subgroup,and ficusphila subgroup were all type C.The karyotypes of takahashii subgroup and suzukii subgroup were both type C and type D.The montium subgroup had six kinds of karyotypes types B,C,C',D,D',and E.The ananassae subgroup had three kinds of karyotypes:types F,G,and H.Thus,the melanogaster species group was classified into five pedigrees based on the diversity of these karyotypes:1)elegans;2)eugracilis-melanogasterficusphila;3)takkahashii-suzukii;4)montium;5)ananassae.The above-mentioned results in karyotypic evolution were consistent with those of DNA sequence analysis reported by Yang except for the elegans subgroup and this subgroup was considered as the ancestral subgroup.Karyotype analysis of the same drosophila from different isofemale lines indicated that the same Drosophila from different places showed karyotypic variation which might be due to different geographical environment and evolutionary degree or interaction between the two factors. 展开更多
关键词 DROSOPHILA Drosophila melanogaster species group KARYOTYPE genetic relationships EVOLUTION
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伊米果蝇种组(Drosophila immigrans species group)H2a-H2b和Cyt b分子系统发育关系(简报)
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作者 闫秀英 曾庆韬 +1 位作者 杨勇 钱远槐 《分子细胞生物学报》 CSCD 北大核心 2006年第3期277-280,共4页
In order to investigate molecular phylogenetic relationships of Drosophila immigransspecies group,nucleotide sequences of H2a-H2b spacer regions and partial nucleotide sequences of Cytochrome b gene for five specieses... In order to investigate molecular phylogenetic relationships of Drosophila immigransspecies group,nucleotide sequences of H2a-H2b spacer regions and partial nucleotide sequences of Cytochrome b gene for five specieses subgroup in Drosophila immigrans species group and D.hydei which was selected as outgroup were acquired. Phylogenetic trees were reconstructed using maximum parsimony,maximum likelihood,neighbor joining and Bayesian methods based on H2a-H2b and Cyt b DNA sequences. The results indicated that Drosophila curviceps species subgroup is located at the base of molecular trees, diverged first in this group; the second clade is Drosophila quadrilineata species subgroup; the third is Drosophila hypocausta species subgroup; the fourth is Drosophila immigrans species subgroup; Drosophila nasuta species subgroup is the last diverged clade. Moreover,the phylogentic relationships of seven specieses in Drosophila nasuta subgroup was investigated. 展开更多
关键词 伊米果蝇种组 组蛋白H2a-H2b间隔区 细胞色素B 系统关系
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Research on the path of effective management of participation in joint-venture railway companies by China railway group 被引量:1
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作者 Shaoni Zhou Zhitian Zhou Chenxia Kang 《Railway Sciences》 2024年第4期530-539,共10页
Purpose-Following the regional restructuring,the number of joint-venture railway companies in which the Group participates has significantly increased.This paper aims to explore the challenges faced by China Railway G... Purpose-Following the regional restructuring,the number of joint-venture railway companies in which the Group participates has significantly increased.This paper aims to explore the challenges faced by China Railway Group in managing participation in joint-venture railway companies.The study seeks to propose specific approaches to ensure the effective management of these companies,thereby maximizing the benefits of the regional restructuring and supporting the development of a strong transportation country and a modern infrastructure system.Design/methodology/approach-Based on the change in the shareholding relationship between China Railway Group and the joint-venture railway companies,and considering the current situation of the regional restructuring of these companies,as well as the insights from existing literature and typical case studies,this paper proposes some specific paths for effective management of joint-stock railway companies which China Railway Group participated in.Findings-The problems in participation management are the unclear dual leadership role of the party committee,the lack of discourse power,the lack of synergy between shareholders,the increasing risk of sustainable operation of the loss-making companies and the role of dispatched personnel is not fully played.Based on the theories,combined with the existing research and practical cases,the paper proposed specific approaches,such as perfecting top-level system design,maintaining the discourse power,carrying out differentiated management,arranging personnel rationally,arranging shareholders synergy,and innovating methods to provide references for China Railway Group’s subsequent management of joint venture railway companies.Originality/value-This paper contributes to the existing literature by providing a comprehensive analysis of the challenges faced by China Railway Group in managing participation in joint-venture railway companies following the regional restructuring.The study offers novel insights and practical recommendations for addressing these challenges.The findings can serve as valuable references for China Railway Group’s subsequent management of joint-venture railway companies which participated in,as well as for other stateowned enterprises facing similar challenges in managing their joint ventures. 展开更多
关键词 China railway group Joint venture railway companies Participated relationship Effective management
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Consistency in <i>Z</i>-<i>R</i>Relationship Variability Regardless Precipitating Systems, Climatic Zones Observed from Two Types of Disdrometer 被引量:1
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作者 Bakary Bamba Abé Delfin Ochou +1 位作者 Eric-Pascal Zahiri Modeste Kacou 《Atmospheric and Climate Sciences》 2014年第5期941-955,共15页
Data from rain Drop Size Distributions gathered on five sites in Africa as well as those of the pilot site in Kourou (French Guyana, South America), located in different climatic zones, and collected by two types of d... Data from rain Drop Size Distributions gathered on five sites in Africa as well as those of the pilot site in Kourou (French Guyana, South America), located in different climatic zones, and collected by two types of disdrometer (the impact JW RD-69 disdrometer and the Optical Spectro-Pluviometer, OSP) are used to study the consistency of the reflectivity factor-rain rate at the ground (Z-R) relationship variability. The results clearly confirm that the relationship Z-R knows a large spatial variability, from a type of precipitation to another and within the same precipitation regardless the type of disdrometer used for DSD measurements. Base on the similarity of the relations reflectivity factor-rain rate and ratio median volume diameter over the total number of drops-rain rate, the variability of the Z-R coefficients (A, b) through the simultaneously implication of the size and number of drops which characterize the DSD was exhibited. It was shown that the relationships A-α and b-β designed to understand the involvement of parameters D0 and NT of DSD in the variability of the relationship Z-R are similar regardless the types of disdrometer used. However, the relations A-α in the Sahelian region appear to deviate from those of Guinean, equatorial and Soudanian zones. The plausible reasons were discussed. 展开更多
关键词 Drop Size Distributions CONSISTENCY in z-r relationship VARIABILITY Squall Lines Thunderstorm Stratiform Rain JW RD-69 DISDROMETER Optical Spectro-Pluviometer OSP
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An overview of the semantic class of the word groups of the industry terminology in "Exploitation of the Works of Nature"
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作者 ZHAO Yue 《International English Education Research》 2018年第1期98-100,共3页
Since the printing and publication of the first carved edition of"Exploitation of the Works of Nature" in 1637 (the tenth year of Chongzhen in the Ming Dynasty), it has been 380 years of history. It is an encyclop... Since the printing and publication of the first carved edition of"Exploitation of the Works of Nature" in 1637 (the tenth year of Chongzhen in the Ming Dynasty), it has been 380 years of history. It is an encyclopedia describing China's ancient agricultural and handicraft technologies, which occupies an important position in the history of the world science and technology, and the author Song Yingxing is praised by the British expert on the world science and technology history Dr. Joseph Needham as the "Chinese Diderot". This book is of great value in the language and the cultural researches. From the perspective of the linguistics, the technical terminologies on the agriculture, the handicraft and other disciplines in this paper are classified and analyzed from the semantic point of view, so as to provide an empirical reference for the better dissemination of the book and the diachronic study of the Chinese terminologies. 展开更多
关键词 Terms relationships word groups
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A new group contribution-based method for estimation of flash point temperature of alkanes
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作者 戴益民 刘辉 +5 位作者 陈晓青 刘又年 李浔 朱志平 张跃飞 曹忠 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期30-36,共7页
Flash point is a primary property used to determine the fire and explosion hazards of a liquid. New group contribution-based models were presented for estimation of the flash point of alkanes by the use of multiple li... Flash point is a primary property used to determine the fire and explosion hazards of a liquid. New group contribution-based models were presented for estimation of the flash point of alkanes by the use of multiple linear regression(MLR)and artificial neural network(ANN). This simple linear model shows a low average relative deviation(AARD) of 2.8% for a data set including 50(40 for training set and 10 for validation set) flash points. Furthermore, the predictive ability of the model was evaluated using LOO cross validation. The results demonstrate ANN model is clearly superior both in fitness and in prediction performance.ANN model has only the average absolute deviation of 2.9 K and the average relative deviation of 0.72%. 展开更多
关键词 flash point alkane group contribution artificial neural network(ANN) quantitative structure-property relationship(QSPR)
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