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Molecular Plant 2008年第5期1卷 794-799页

作者： Sung-Aeong Oh Valerie Bourdon Madhumita Das 'Pal Hugh dickinson David Twell Department of Biology University of Leicester University Road Leicester LE1 7RH UK Department of Plant sciences University of Oxford South Parks Road Oxford OXl 3RB UK Present address: Division of Plant Biosciences Kyungpook National University Daegu 702-701 South Korea

Asymmetric cell division at pollen mitosis I （PMI） is required to specify the differential fate of the daughter vegetative and generative cells. Cytokinesis at PMI displays specialized features, and it has been suggested that there might be distinct molecular pathways underpinning different modes of cytokinesis in plants. Activation of the NACK- PQR MAP kinase signaling pathway, which is essential for somatic cell cytokinesis in tobacco, depends upon the NACK1 and NACK2 kinesin-related proteins. Their Arabidopsis orthologs, HINKEL （HIK） and TETRASPORE （TES）, were reported to be essential for cytokinesis in somatic cells and in microsporocytes, respectively. More recently, HIK and TES were shown to have a functionally redundant role in female gametophytic cytokinesis. We report here that HIK and TES are co-expressed in microspores and developing pollen, and, through analysis of microspore and pollen development in double heterozygore mutants, the occurrence of cell plate expansion defects during cytokinesis at PMI. The data demonstrate a functionally redundant role for HIKand TES in cell plate expansion during male gametophytic cytokinesis, extending the concept that different modes of cytokinesis are executed by a common signaling pathway, but reinforcing the individuality of gametophytic cytokinesis in its requirement for either TES or HIK.

关键词：胞质分裂个性花粉拟南芥属心肌梗死血气分析胰岛素铍男(雄)性女(雌)性

A Genetic Algorithm for Identifying Overlapping Communities in Social Networks Using an Optimized Search Space

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Social Networking 2013年第4期2卷 193-201页

作者： Brian dickinson Benjamin Valyou Wei Hu Department of Computer Science Houghton College Houghton USA

There are currently many approaches to identify the community structure of a network, but relatively few specific to detect overlapping community structures. Likewise, there are few networks with ground truth overlapping nodes. For this reason,we introduce a new network, Pilgrim, with known overlapping nodes, and a new genetic algorithm for detecting such nodes. Pilgrim is comprised of a variety of structures including two communities with dense overlap,which is common in real social structures. This study initially explores the potential of the community detection algorithm LabelRank for consistent overlap detection;however, the deterministic nature of this algorithm restricts it to very few candidate solutions. Therefore, we propose a genetic algorithm using a restricted edge-based clustering technique to detect overlapping communities by maximizing an efficient overlapping modularity function. The proposed restriction to the edge-based representation precludes the possibility of disjoint communities, thereby, dramatically reducing the search space and decreasing the number of generations required to produce an optimal solution. A tunable parameterr allows the strictness of the definition of overlap to be adjusted allowing for refinement in the number of identified overlapping nodes. Our method, tested on several real social networks, yields results comparable to the most effective overlapping community detection algorithms to date.

关键词： Overlapping Community Detection Genetic Algorithm Social Networks

Dimensionality Reduction of Distributed Vector Word Representations and Emoticon Stemming for Sentiment Analysis

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Journal of Data Analysis and Information Processing 2015年第4期3卷 153-162页

作者： Brian dickinson Michael Ganger Wei Hu Department of Computer Science Houghton College Houghton NY USA

Social media platforms such as Twitter and the Internet Movie Database (IMDb) contain a vast amount of data which have applications in predictive sentiment analysis for movie sales, stock market fluctuations, brand opinion, or current events. Using a dataset taken from IMDb by Stanford, we identify some of the most significant phrases for identifying sentiment in a wide variety of movie reviews. Data from Twitter are especially attractive due to Twitter’s real-time nature through its streaming API. Effectively analyzing this data in a streaming fashion requires efficient models, which may be improved by reducing the dimensionality of input vectors. One way this has been done in the past is by using emoticons;we propose a method for further reducing these features through identifying common structure in emoticons with similar sentiment. We also examine the gender distribution of emoticon usage, finding tendencies towards certain emoticons to be disproportionate between males and females. Despite the roughly equal gender distribution on Twitter, emoticon usage is predominately female. Furthermore, we find that distributed vector representations, such as those produced by Word2Vec, may be reduced through feature selection. This analysis was done on a manually labeled sample of 1000 tweets from a new dataset, the Large Emoticon Corpus, which consisted of about 8.5 million tweets containing emoticons and was collecting over a five day period in May 2015. Additionally, using the common structure of similar emoticons, we are able to characterize positive and negative emoticons using two regular expressions which account for over 90% of emoticon usage in the Large Emoticon Corpus.

关键词： Natural Language Emoticon Twitter Review

History,Academics and Progress of the Society

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History,Academics and Progress of the Society

Determining Leaders and Communities on Networks Using Neighborhood Similarity

文明的和谐与共同繁荣：文明的普遍价值和发展趋向——北京论坛（2008）

作者： Harry Thomas dickinson the Royal Historical Society and Historical Association of Great Britain Vice President

The Beijing Forum this year has gathered together about 300 scholars in many different academic disciplines,and representing 40 countries or regions,to discuss in detail issues under the general themes of ’The Harmon...

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Social Networking 2014年第1期3卷 50-57页

作者： Benjamin Valyou Brian dickinson Wei Hu Computer Science Department Houghton College Houghton USA

Networks are used to represent interactions in a wide variety of fields, like biology, sociology, chemistry, and more. They have a great deal of salient information contained in their structures, which have a variety of applications. One of the important topics of network analysis is finding influential nodes. These nodes are of two kinds —leader nodes and bridge nodes. In this study, we propose an algorithm to find strong leaders in a network based on a revision of neighborhood similarity. This leadership detection is combined with a neighborhood intersection clustering algorithm to produce high quality communities for various networks. We also delve into the structure of a new network, the Houghton College Twitter network, and examine the discovered leaders and their respective followers in more depth than which is frequently attempted for a network of its size. The results of the observations on this and other networks demonstrate that the community partitions found by this algorithm are very similar to those of ground truth communities.

关键词： Community Detection Community Leaders Node Importance Centrality Neighborhood Similarity Modularity

早产儿出院后科学追赶,对EUGR说不!——Jane dickinson Carver博士专访

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时尚育儿 2009年第6期 110-111页

作者： Jane dickinson Carver 盛晓阳美国南佛罗里达大学医学院儿科新生儿分部美国肠外肠内营养学会美国营养学会美国临床营养学会儿科研究协会南方儿科研究协会上海交通大学医学院附属新华医院儿童与青少年保健科

面对全世界范围都日益增高的早产儿发生率,全球新生儿营养专家如何看待这些问题?又会带来什么样的建议呢?日前,全球著名新生儿营养学家、现任美国南佛罗里达大学医学院儿科新生儿分部副教授的Jane D Carver博士出席了中华医学会儿科分... 详细信息

面对全世界范围都日益增高的早产儿发生率,全球新生儿营养专家如何看待这些问题?又会带来什么样的建议呢?日前,全球著名新生儿营养学家、现任美国南佛罗里达大学医学院儿科新生儿分部副教授的Jane D Carver博士出席了中华医学会儿科分会在京举办的早产儿院外喂养对策学术论坛,带来了她几十年倾力研究的早产儿院内院外营养研究攻略。

关键词：早产儿出院后配方奶新生儿营养足月儿专用配方母乳喂养住院期间生长发育博士

Gender Prediction on Twitter Using Stream Algorithms with N-Gram Character Features

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International Journal of Intelligence Science 2012年第4期2卷 143-148页

作者： Zachary Miller Brian dickinson Wei Hu Department of Computer Science Houghton College Houghton USA

The rapid growth of social networks has produced an unprecedented amount of user-generated data, which provides an excellent opportunity for text mining. Authorship analysis, an important part of text mining, attempts to learn about the author of the text through subtle variations in the writing styles that occur between gender, age and social groups. Such information has a variety of applications including advertising and law enforcement. One of the most accessible sources of user-generated data is Twitter, which makes the majority of its user data freely available through its data access API. In this study we seek to identify the gender of users on Twitter using Perceptron and Nai ve Bayes with selected 1 through 5-gram features from tweet text. Stream applications of these algorithms were employed for gender prediction to handle the speed and volume of tweet traffic. Because informal text, such as tweets, cannot be easily evaluated using traditional dictionary methods, n-gram features were implemented in this study to represent streaming tweets. The large number of 1 through 5-grams requires that only a subset of them be used in gender classification, for this reason informative n-gram features were chosen using multiple selection algorithms. In the best case the Naive Bayes and Perceptron algorithms produced accuracy, balanced accuracy, and F-measure above 99%.

关键词： Twitter Gender Identification Stream Mining N-gram Feature Selection Text Mining

Exertional heat illness risk factors and physiological responses of youth football players

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Journal of Sport and Health Science 2021年第1期10卷 91-98页

作者： Susan W.Yeargin John J.dickinson Dawn M.Emerson Jessica Koller Toni M.Torres-McGehee Zachary Y.Kerr Department of Exercise Science University of South CarolinaColumbiaSC 29208USA Palmetto Health/USC Orthopedic Center Keenan High SchoolColumbiaSC 29203USA Department of Health Sportand Exercise SciencesUniversity of KansasLawrenceKS 66045USA Surgi-Care Inc. BostonMA 02115USA Department of Exercise and Sport Science University of North CarolinaChapel HillNC 27599-8700USA

Objective:To determine which intrinsic and extrinsic exertional heat illness(EHI)risk factors exist in youth American football players and observe perceptual and physiological responses of players during events(games and practices).Methods:Cross-sectional cohort study observing 63 youth football players,varying in *** variables were league(weightrestricted(WR,n=27)and age-restricted(AR,n=36))and event *** variables were anthropometrics,work-to-rest ratio,and wet bulb globe *** variables included preparticipation examination and uniform configuration.A subset of 16 players participated in physiological variables(heart rate and gastrointestinal temperature).Data collection occurred on 7 AR and 8 WR nonconsecutive practices and the first 3 games of the ***:Mean values for anthropometric variables were higher(p<0.05)in the AR league than the WR *** time(χ^2(1,111)=4.232;p=0.039)and rest time(χ^2(1,111)=43.41;p<0.001)were significantly greater for games,but ratios were significantly higher for practices(χ^2(1,111)=40.62;p<0.001).The majority of events(77%)observed were in black and red flag wet bulb globe temperature risk categories.A total of 57%of the players had a preparticipation examination,and up to 82%of events observed were in full *** gastrointestinal temperature and heart rate responses ranged widely and no players reached critical ***:Extrinsic(disproportionate work ratios,environmental conditions)and intrinsic(higher body mass index)EHI risk factors exist in youth *** risk factors may be influenced by event and league *** youth football organizations need to create thorough guidelines that address EHI risk factors for local leagues to adopt.

关键词： Adolescents Anthropometrics Core temperature Heat exchange Pediatric Wet bulb globe temperature

Evaluating Common Land Model Energy Fluxes Using FLUXNET Data

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Advances in Atmospheric Sciences 2017年第9期34卷 1035-1046页

作者： Xiangxiang ZHANG Yongjiu DAI Hongzhi CUI Robert E.dickinson Siguang ZHU Nan WEI Binyan YAN Hua YUAN Wei SHANGGUAN Lili WANG Wenting FU College of Global Change and Earth System Science Beijing Normal University School of Atmospheric Sciences Sun Yat-sen University Department of Geological Sciences the University of Texas at Austin

Given the crucial role of land surface processes in global and regional climates, there is a pressing need to test and verify the performance of land surface models via comparisons to observations. In this study, the eddy covariance measurements from 20 FLUXNET sites spanning more than 100 site-years were utilized to evaluate the performance of the Common Land Model （CoLM） over different vegetation types in various climate zones. A decomposition method was employed to separate both the observed and simulated energy fluxes, i.e., the sensible heat flux, latent heat flux, net radiation, and ground heat flux, at three timescales ranging from stepwise （30 rain） to monthly. A comparison between the simulations and observations indicated that CoLM produced satisfactory simulations of all four energy fluxes, although the different indexes did not exhibit consistent results among the different fluxes, A strong agreement between the simulations and observations was found for the seasonal cycles at the 20 sites, whereas CoLM underestimated the latent heat flux at the sites with distinct dry and wet seasons, which might be associated with its weakness in simulating soil water during the dry season. CoLM cannot explicitly simulate the midday depression of leaf gas exchange, which may explain why CoLM also has a maximum diurnal bias at noon in the summer. Of the eight selected vegetation types analyzed, CoLM performs best for evergreen broadleaf forests and worst for croplands and wetlands.

关键词： model evaluation Common Land Model FLUXNET