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Invasive weed disrupts facilitation of nutrient uptake in grass-clover assemblage

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Soil Ecology Letters 2024年第1期6卷 89-96页

作者： Wei Zhang rick Muir Nicholas dickinson Faculty of Agriculture and Life Sciences Lincoln UniversityLincoln 7647New Zealand

Nutrient constraints in low-fertility soil were modified by different species ***-clover assemblages benefited both species in terms of nutrient *** of competition and facilitation is *** invasive weed removed essential nutrients from the grazing *** investigate the interplay of competition and facilitation between plants in low-fertility pasture grasslands of New Zealand,we compared nutrient uptake and acquisition of key nutrients of three species from different func-tional *** of Pilosella officinarum(mouse-eared hawk-weed,an invasive weed),Trifolium repens(white clover,a nitrogen fixer)and Dactylis glomerata(cocksfoot,a pasture grass)were planted into a soil with low-to-deficient concentrations of key *** yields were achieved by the grass growing alone but,when the clover and grass had grown together,there were complementary benefits in terms of procurement of a wide range of nutrients from soil despite lower root *** inva-sive weed negated these benefits,and soil nutrients were exploited less efficiently when Pilosella had grown alone or in a mixture with the other *** from the weed removed the benefits of grass-legume *** findings are interpreted to suggest that requirements for legumes to be the main source of nitrogen in pasture grasslands may be compromised unless competitive weeds are controlled to avoid disrupted procurement of key *** is likely these constraints to nutrient procurement would similarly impact conservation grasslands.

关键词： soil ferility facilitation species coexistence weed invasion legumes

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

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对气候变化估计的不确定性的述评

气象科技 1990年第6期18卷 18-23页

作者： r.E.dickinson 芳子美国大气研究中心

尽管气候模式提供了未来气候的基本信息,可是仍然存在着许多不确定性。本述评讨论气候系统对不断增加的大气微量气体强迫的响应问题。最受关注的不确定性有:海洋热吸收所控制的瞬时调整;高纬的冰雪覆盖;云辐射特性的变化以及与海陆分布... 详细信息

尽管气候模式提供了未来气候的基本信息,可是仍然存在着许多不确定性。本述评讨论气候系统对不断增加的大气微量气体强迫的响应问题。最受关注的不确定性有:海洋热吸收所控制的瞬时调整;高纬的冰雪覆盖;云辐射特性的变化以及与海陆分布和与大气内部动力学相联系的区域气候型的变化。

关键词：气候变化大气微量气体未来气候气候系统气候模式大气环流模式气候型高纬全球增暖全球温度

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

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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

Effect of growing media and their constituents on fungus gnat, Bradysia 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 AMY 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, Bradysia sp. nr. coprophila adults. The constituents of the most attractive growing medium tested were determined by gas chromatography analysis 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

Bone regeneration Based on Tissue Engineering Conceptions – A 21st Century Perspective

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Bone research 2013年第3期1卷 216-248页

作者： Jan Henkel Maria A.Woodruff Devakara r.Epari roland Steck Vaida Glatt Ian C.dickinson Peter F.M.Choong Michael A.Schuetz Dietmar W.Hutmacher Institute of Health & Biomedical Innovation Queensland University of TechnologyBrisbane Queensland Australia Orthopaedic Oncology Service Princess Alexandra HospitalBrisbane Australia Department of Surgery University of Melbourne St. Vincent's HospitalMelbourne Australia Department of Orthopaedics St. Vincent's HospitalMelbourneAustralia Bone and Soft Tissue Sarcoma Service Peter MacCallum Cancer CentreMelbourne Australia Orthopaedic and Trauma Services Princess Alexandra HospitalBrisbane Australia George W Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlanta GA USA

The role of Bone Tissue Engineering in the field of regenerative Medicine has been the topic of substantial research over the past two decades. Technological advances have improved orthopaedic implants and surgical techniques for bone reconstruction. However, improvements in surgical techniques to reconstruct bone have been limited by the paucity of autologous materials available and donor site morbidity. recent advances in the development of biomaterials have provided attractive alternatives to bone grafting expanding the surgical options for restoring the form and function of injured bone. Specifically, novel bioactive （second generation） biomaterials have been developed that are characterised by controlled action and reaction to the host tissue environment, whilst exhibiting controlled chemical breakdown and resorption with an ultimate replacement by regenerating tissue. Future generations of biomaterials （third generation） are designed to be not only osteo- conductive but also osteoinductive, i.e. to stimulate regeneration of host tissues by combining tissue engineer- ing and in situ tissue regeneration methods with a focus on novel applications. These techniques will lead to novel possibilities for tissue regeneration and repair. At present, tissue engineered constructs that may find future use as bone grafts for complex skeletal defects, whether from post-traumatic, degenerative, neoplastic or congenital/developmental ＂origin＂ require osseous reconstruction to ensure structural and functional integrity. Engineering functional bone using combinations of cells, scaffolds and bioactive factors is a promising strategy and a particular feature for future development in the area of hybrid materials which are able to exhibit suitable biomimetic and mechanical properties. This review will discuss the state of the art in this field and what we can expect from future generations of bone regeneration concepts.

关键词： bone tissue engineering regenerative medicine additve manufacturing clinical translation scaffolds

Analysis 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 analysis 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

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 January 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