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On the Number of Polynomials with Small Discriminants in the Euclidean and p-adic Metrics

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Acta Mathematica Sinica,English Series 2012年第3期28卷 469-476页

作者： Jin yUAN Natalia BUDARINA Detta dickinson Department of Mathematics Northwest University Department of Mathematics Logic HouseMaynooth

In this article it is proved that there exist a large number of polynomials which have small discriminant in terms of the Euclidean and p-adic metrics simultaneously. The measure of the set of points which satisfy cer... 详细信息

关键词： Diophantine approximation discriminant polynomial inequalities

Arabidopsis Kinesins HINKEL and TETRASPORE Act Redundantly to Control Cell Plate Expansion during Cytokinesis in the Male Gametophyte

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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

a.ymmetric 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 ana.ysis 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： HINKEL TETRASPORE HIK

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没有一艘船能像一本书

疯狂英语（新读写） 2024年第3期 1-1页

作者： Emily dickinson 佚名(译) 不详

Small RNA Pathways Are in the Angiosperm Male Present and Functional Gametophyte

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Molecular Plant 2009年第3期2卷 500-512页

作者： Robert Grant-Downton Said Hafidh David Twell Hugh G. dickinson Department of Plant Sciences South Parks Rd Oxford OX1 3RB UK Department of Biology University of Leicester University Road Leicester LE1 7RH UK

Small non-coding RNAs are essential for development of the sporophyte, the somatic diploid phase of flowering plants. They are integral to key cellular processes such as defense, generation of chromatin structure, and regulation of native gene expression. Surprisingly, very little is known of their presence and function in the male haploid phase of plant development （male gametophyte/pollen grain）, where dramatic cell fate changes leading to gametogenesis occur over just two mitotic divisions. We show that critical components of small RNA pathways are expressed throughout pollen development, but in a pattern that differs from the sporophyte. We also demonstrate that mature pollen accumulates a range of mature microRNAs, the class of small RNA most frequently involved in post-transcriptional regulation of endogenous gene expression. Significantly, these miRNAs cleave their target transcripts in developing pollen-a process that seemingly contributes to the purging of key regulatory transcripts from the mature pollen grain. Small RNAs are thus likely to make a hitherto unappreciated contribution to male gametophyte gene expression patterns, pollen development, and gametogenesis.

关键词： Pollen plant germline small RNA microRNA epigenetics

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 Zacha.y 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,va.ying 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(py greater for games,but ratios were significantly higher for practices(χ^2(1,111)=40.62;py 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

Effect of growing media and their constituents on fungus gnat, Bra.ysia sp, nr, coprophila （Lintner） adults

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Insect Science 2007年第6期14卷 467-475页

作者： RAyMOND A. CLOyD a.y dickinson RICHARD A. LARSON KAREN A. MARLEy Department of Entomology Kansas State University Manhattan Kansas Division of Biodiversity and Ecological Entomology Illinois Natural History Survey Champaign Illinois University of Illinois Department of Natural Resources and Environmental Sciences Urbana Illinois USA

This study was conducted to determine the attractiveness of two growing media, commonly utilized in greenhouses, to fungus gnat, Bra.ysia sp. nr. coprophila adults. The constituents of the most attractive growing medium tested were determined by gas chromatography ana.ysis using a steam-distillation procedure. We found that fungus gnat adults were more attracted to the growing medium, SB300 Universal Professional Growing Mix, which contains composted bark, than to another growing medium （Sunshine LC1 Mix） and their components when tested in a series of laboratory experiments using multiple-choice experimental arenas. A higher percentage of fungus gnat adults were attracted to moist SB300 （92%） than SB300 growing medium that had been oven dried （8%）. In addition, fungus gnat adults preferred SB300 although they had been reared on Sunshine LC1 Mix. When comparing the SB300 fresh from the bag to growing medium that had been pasteurized and moistened with water, gas chromatographic-mass spectroscopic data showed there were declines in several terpenoid constituents as well as an increase in fatty acids and cyclosulfur. The results of this study indicate that B. sp. nr. coprophila adults prefer certain growing media, which may assist greenhouse producers in managing fungus gnats in crop production systems.

关键词： Attraction fungus gnats growing medium pest management preference,steam distillation

Ana.ysis on the influence factors of Bitcoin’s price based on VEC model

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Financial Innovation 2017年第1期3卷 37-49页

作者： yechen Zhu David dickinson Jianjun Li School of Finance Central University of Finance and EconomicsBeijing 100081China Department of Economics Birmingham Business SchoolUniversity of BirminghamBirmingham B152TTUK

Background:Bitcoin,the most innovate digital currency as of now,created since 2008,even through experienced its ups and downs,still keeps drawing attentions to all parts of *** relies on peer-to-peer network,achieved decentralization,anonymous and *** the most representative digital currency,people curious to study how Bitcoin’price changes in the ***:In this paper,we use monthly data from 2011 to 2016 to build a VEC model to exam how economic factors such as Custom price index,US dollar index,Dow jones industry average,Federal Funds Rate and gold price influence Bitcoin ***:From empirical ana.ysis we find that all these variables do have a long-term *** dollar index is the biggest influence on Bitcoin price while gold price influence the ***:From our result,we conclude that for now Bitcoin can be treated as a speculative asset,however,it is far from being a proper credit currency.

关键词： Bitcoin price Gold price US dollar index VEC model

a.ymptotic Marginal Tax Rate of Individual Income Tax in China

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Economic and Political Studies 2014年第2期2卷 121-138页

作者： ZHENyA LIU WU yANG DAVID dickinson the School of Finance Renmin University of China he Department of Economics University of Birmingham the School of International Trade and Economics Central University of Finance and Economics of China the Department of Economics University of Birmingham

This paper examines the a.ymptotic marginal rate of individual income tax which maximizes China's social welfare through numerical simulation based on the elasticity of China's labor supply, income distribution and the social objectives of redistribution in accordance with the optimal direct taxation theory. Taking advantage of the optimal direct taxation model with consideration of the income effect, it comes to the conclusion that combined with China's reality, the a.ymptotic marginal rate of individual labor income tax in China should be between 35% and 40%.

关键词： reform of individual income tax a.ymptotic marginal tax rate optimal direct taxation theory

Global Community of Disaster Risk Reduction Scientists and Decision Makers Endorse a Science and Technology Partnership to Support the Implementation of the Sendai Framework for Disaster Risk Reduction 2015–2030

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International Journal of Disaster Risk Science 2016年第1期7卷 108-109页

作者： Chloe dickinson Amina Aitsi-Selmi Pedro Basabe Chadia Wannous Virginia Murray Public Health England United Nations Office for Disaster Risk Reduction the UNISDR Science and Technology Conference on the Implementation of the Sendai Framework for Disaster Risk Reduction 2015–2030 the UNISDR Scientific and Technical Advisory Group(STAG)

At the first gathering of its kind on the role of science in implementing the Sendai Framework for Disaster Risk Reduction 2015–2030,over 750 scientists,policymakers,business people,and practitioners met in Geneva from Janua.y 27–29,*** UNISDR Science and Technology Conference on the Implementation of the Sendai Framework for Disaster Risk Reduction 2015–2030 fea-

关键词： work Global Community of Disaster Risk Reduction Scientists and Decision Makers Endorse a Science and Technology Partnership to Support the Implementation of the Sendai Framework for Disaster Risk Reduction 2015