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Positive interactions by cushion plants in high mountains:fact or artifact?

Journal of Plant Ecology 2016年第2期9卷 117-123页

作者： Marco A.Molina-Montenegro Rómulo Oses ian S.Acuña-Rodríguez Cristian Fardella Ernesto I.Badano Patricio Torres-Morales Jorge Gallardo-Cerda Cristian Torres-Díaz Instituto de Ciencias Biológicas Universidad de TalcaAvda.Lircay s/nTalcaChile Centro de Estudios Avanzados en ZonasÁridas(CEAZA) Facultad de Ciencias del MarUniversidad Católica del NorteCoquimboChile División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaCamino a la Presa San José2055Colonia Lomas ta Sección CP 78216San Luis PotosíSLPMéxico 4 Instituto de Ciencias Ambientales y EvolutivasUniversidad Austral de ChileValdiviaChile Departamento Científico Instituto Antártico Chileno(INACH)Punta ArenasChile Laboratorio de Genómica y Biodiversidad(LGB) Departamento de Ciencias NaturalesUniversidad del Bío-BíoChillánChile

Positive interactions are defined as non-trophic interactions where at least one of the interacting species is benefited in terms of fitness and the other remains ***,the bidirectional feedbacks between species may be positive,neutral or ***,if facilitated species induce negative effects on their‘nurses’,the assumed definition of positive interactions could be *** We assessed if ecological interactions between cushions of Azorella madreporica and their facilitated species are ***,we tested if cover of facilitated species has any costs for cushion plants from an ecophysiological perspective,and if these costs increase with the amount of cover of facilitated *** addition,through pathway analysis and correlations,we assessed if cover and richness of facilitated species have a direct and/or indirect effect on the fitness of cushion *** Findings We found that facilitated plant species induced a significant cost for their nurses(cushion plants),and this cost increases with cover of the facilitated ***,the facilitated species exert a strong direct negative effect on the cushion’s fitness and a moderate indirect negative cost evident through the nutrient status and physiological performance of cushion *** thus contribute evidence that positive interactions between high mountain cushion plants of central Chile and their‘facilitated’species may be an artifact more than a fact,especially when bidirectional effects are considered;contrasting with the majority of studies that document only one side of the interaction.

关键词： cushion plants facilitation nurse effect positive interactions stress gradient hypothesis

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The Effects of a Four-Week neuromuscular Training Program on Landing Kinematics in Pre-and Post-Peak Height Velocity Male Athletes

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Journal of Science in Sport and Exercise 2021年第1期3卷 37-46页

作者： Paul J.Read Jon L.Oliver ian J.Dobbs Megan A.Wong nakul Tumkur Anil Kumar Rhodri S.Lloyd Institute of Sport Exercise and HealthUniversity College LondonLondonUK School of Sport and Exercise University of GloucestershireGloucesterUK School of Sport and Health Sciences Cardiff Metropolitan UniversityCardiffUK Sport Performance Research Institute New Zealand(SPRINZ)AUT UniversityAuckland Centre for Sport Science and Human Performance Waikato Institute of TechnologyHamiltonNew Zealand

Purpose neuromuscular training aims to enhance motor skill competency and increase muscle ***,the effectiveness of short-duration interventions focused on addressing lower limb injury risk factors in male youth athletes at different stages of maturity remains *** Forty-eight young male academy cricket players[pre-peak height velocity(PHV)(n=26)and post-PHV(n=22)]were subdivided into an experimental group(EXP)who completed a 4-week progressive neuromuscular training program and controls(COn)participating in sport training *** in injury risk were examined using the Tuck Jump Assess-ment(TJA)and Landing Error Scoring System(LESS).Results Total LESS score was significantly lower in both EXP maturity groups compared to COn following the 4-week program(10 to 6 and 6 to 4(~20%to 40%))in the pre-and post-PHV EXP groups,*** within-group reductions in total LESS score were shown for the pre-PHV EXP group only(Pnversely,greater changes in TJA total score were shown in post-PHV(5 to 3;40%)versus pre-PHV EXP(6 to 4.5;26%).Pre-PHV players showed positive changes in individual LESS criteria indicative of frontal plane control but not in knee valgus during the TJA,whereas post-PHV players did improve this *** This study indicates it is possible to reduce TJA and LESS scores in male youth athletes by performing a 4-week neuromuscular training program,improving landing mechanics and reducing injury risk irrespective of maturity,but their effects are somewhat influenced by stage of maturation and the task performed.

关键词： Injury risk Maturation Landing

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Soil and altitude drive diversity and functioning of Brazilian Páramos(campo de altitude)

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Journal of Plant Ecology 2017年第5期10卷 771-779页

作者： Andreza Viana neri Gladson Ramon Alves Borges João Augusto Alves Meira-neto Luiz Fernando Silva Magnago ian Michael Trotter Carlos Ernesto GRSchaefer Stefan Porembski Departamento de Biologia Vegetal Laboratório de Ecologia e Evolução de PlantasUniversidade Federal de ViçosaPH RolfsS/NCampus UniversitárioViçosaMinas Gerais 36570-900Brazil Departamento de Biologia Setor de Ecologia e ConservaçãoUniversidade Federal de LavrasLavrasMinas Gerais 37200-000Brazil Departamento de Economia Rural Universidade Federal de ViçosaPH RolfsS/NCampus UniversitárioViçosaMinas Gerais 36570-900Brazil Departamento de Solos Universidade Federal de ViçosaPH RolfsS/NCampus UniversitárioViçosaMinas Gerais 36570-900Brazil Allgemeine und Spezielle Botanik Institut für BiowissenschaftenUniversität RostockWismarsche Str.8D-18051 RostockGermany

Aims the vegetation on Brazilian Páramos consists of assemblages that are driven mainly by the influence of strong environmental *** is very important to understand the effect of environmental varia-tion on taxonomic diversity and on functional *** the lack of information about the functional diversity in Brazilian Páramos,we analyzed for the first time the effects of altitude and edaphic attributes on functional traits,as well as on taxonomic and functional *** also wanted to answer the questions:Which ecological strategies are favorable in high-altitude grassland?Does soil attributes determine distributions of traits in high-altitude grassland?considering the studied altitudinal gradient is altitude an important variable in the community assembly?Methods the study was conducted on three mountains:Mammoth(1850 m),Elephant(1790 m)and totem(1690 m)in Serra do Brigadeiro State Park,Minas Gerais State,*** mountains represent the‘Serra das cabeças’,a smaller ridge that is surrounded by the Atlantic Forest,one of the 25 hotspot of *** samples were taken using 100 plots of 1 m2 per mountain that were randomly *** plants except mosses were *** taxonomic diversity was evaluated using richness,Shannon diversity,effective number of species and Pielou *** the functional diver-sity,we considered the functional richness,functional evenness and functional *** linear models(GLM/Poisson and quasi-Poisson)were used to evaluate the effect of abiotic variables(altitude,soil depth and soil chemical attributes)on biotic variables(number of species and individuals,life form,dispersal and fruit type)and ordinary least squares regression to evaluate the effect of abiotic variables on the functional and taxonomic *** Findingsthe soil variables presented a considerable edaphic gradient associated with *** soil in Serra das cabeças plays an important role for the

关键词： mountain conservation vegetation islands functional diversity life form highland grassland functional traits

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贝叶斯框架下的非参数估计Graph Cuts分割算法

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中国图象图形学报 2011年第6期16卷 947-952页

作者：蒋建国郭艳蓉郝世杰詹曙李鸿 ian Ross 合肥工业大学计算机与信息学院合肥230009 安全关键工业测控技术教育部工程研究中心合肥230009 安徽医科大学第一附属医院骨科合肥230022 London Health Science Center London Ontario Canada N6A 5A5

假设图像中各像素灰度值是具有一定概率分布的随机变量,由贝叶斯定理,正确分割观测图像等价于求出具有最大后验概率的实际图像估计。在此框架下,提出了一种改进型Graph Cuts图像分割算法。与传统GraphCuts分割算法相比,该算法在模型建... 详细信息

假设图像中各像素灰度值是具有一定概率分布的随机变量,由贝叶斯定理,正确分割观测图像等价于求出具有最大后验概率的实际图像估计。在此框架下,提出了一种改进型Graph Cuts图像分割算法。与传统GraphCuts分割算法相比,该算法在模型建立上有两个方面的改进:1)将模糊C均值聚类引入数据约束能量函数来得到各像素在某个标记下的概率,改善了收敛性能;2)使用非参数方法估计图像的统计分布,然后用此统计量构成图像分割的先验概率,并保证分割结果的局部平滑。由于非参数估计是由样本直接估计得到的结果,特别适用于小样本和分布函数不恒定的情况,因此拓展了算法的适用范围。实验结果表明,改进算法在遥感图像分割和医学图像分割中均提高了分割精度,证明了该算法的有效性。

关键词： Graph Cuts 贝叶斯图像分割模糊C均值非参数估计

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Structural basis of human H7n9 influenza virus neutralization by human antibody H7.167

Structural basis of human H7N9 influenza virus neutralizatio...

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第五届中国结构生物学学术讨论会

作者： Heng Zhang Yu-Hui Dong ian A.Wilson Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences Department of Integrative Structural and Computational Biology The Scripps Research Institute

An outbreak of avian-origin H7n9 influenza virus has occurred in China since March 2013 and caused hundreds of human-infection cases worldwide. The hemagglutinin（HA） of influenza viruses is the major surface glycoprotein facilitating virus entry and infection of host cells and is the major target of neutralizing antibodies. The naturally occurring human monoclonal antibody H7.167 was isolated from the memory B cells of human infected with H7n9 vaccine strain（A/Shanghai/02/2013, Sh2/H7） and exhibited efficient neutralization activity against influenza H7 strains. Here, we report the crystal structure of H7.167 Fab in complex with Sh2/H7 HA and provide the structural basis of H7.167 neutralization specialty for H7 subtype. H7.167 targets a highly conserved epitope adjacent to the receptor-binding site（RBS） using its complementarity-determining regions（CDRs） through a series of hydrogen bonds and van der Waals interactions. The heavy chain appears to bind to the residues including R131, and n157 to n158 B close to 150-loop, 130-loop and 190-helix that constitute the RBS, while the light chain appears to bind additional residues, including F161, S187, K200 and n248, which are distant from the RBS. The contacting residues in H7 HA, including the insertion of residues D158 A and n158 B in the 150-loop, differ remarkably from the corresponding residues in H1/H2/H3/H5 HAs. Moreover, the 150-loop has a unique conformation in H7 HA compared with other subtype HA, where n157 and n158 B are key residues responsible for the neutralization activity of the antibody. These remarkable structural characters are likely associated with the particular specificity of H7.167 neutralization for H7. This identified epitope in the HA RBS may be of use in design of novel immunogens for development of H7 vaccines or small-molecule therapeutics to block transmission of H7 avian flu to humans.

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The Development and Operational Testing of an Underwater Bait Setting System to Prevent the Mortality of Albatrosses and Petrels in Pelagic Longline Fisheries

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Open Journal of Marine Science 2015年第1期5卷 1-12页

作者： Graham Robertson Phillip Ashworth Peter Ashworth ian Carlyle Steven G. Candy Australian Antarctic Division Kingston Australia Amerro Engineering Warana Australia

Longline fisheries for tunas and tuna-like species present an existential threat to many populations of albatrosses and petrels worldwide. To prevent this form of mortality we developed a new technology designed to deploy baited hooks underwater beyond the dive depths of?seabirds (6 - 10 m for the species most commonly caught). The underwater bait setter is a stern-mounted, hydraulically-operated and computer-controlled?device that catapults?baited hooks underwater in a steel capsule?connected to hydraulic winches by Spectra®rope. Baits are flushed from the capsule by water pressure through a spring-loaded bait release door. The chief engineering challenges in the developmental stageswere ensuring:?1) bait delivery?to target depths with cycle times (time from release to recovery) that were practical for fishing operations;?2) bait retention in the capsule (no drop-outs) on the descent phase of the cycle;?3) baits, upon?release at target depth, were not drawn up the water column on the capsule recovery phase (from possible hook-ups and/or suction);and?4) the retention of baits?on?hooks post-release from the capsule was not affected by the mechanical release underwater. Operational trials with the final version of the capsule yielded?satisfactory cycle times to depths of 6 - 10 m. All baits were retained?in the capsule on the descent and?released as required?at target depths (n = 606 deployments). Bait retention on hooks post release from the capsule and retention on hooks hand-set at the surface (the conventional method) were statistically indistinguishable.?The underwater bait setter is modular in construction and can be fitted to all types of vessel sterns.

关键词： Seabird Bycatch Longline Fisheries Underwater Setting Marine Engineering Innovation Co-Operative Research

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The Effect of Intraocular Pressure Lowering Medications on the Pressure Spike Associated with Intravitreal Injection

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Open Journal of Ophthalmology 2015年第4期5卷 149-154页

作者： Olya Pokrovskaya ian Dooley Salma Babiker Catherine Croghan Claire Hartnett Anthony Cullinane Department of Ophthalmology Mater Miscericordiae University Hospital Dublin Ireland Department of Ophthalmology Cork University Hospital Cork Ireland

Aim: This study investigates whether the post intravitreal injection intraocular pressure (IOP) spike is modifiable with the use of prophylactic apraclonidine and dorzolomide. Methods: The study design was a prospective, randomised controlled trial. 80 eyes undergoing intravitreal injection of anti-VEGF agent were studied. A control group (n = 42) received no IOP lowering drops, and a study group (n = 38) received guttae apraclonidine and dorzolamide 30 to 40 minutes before the intravitreal injection. IOP measurements were taken in both groups using the Perkins tonometer at baseline, immediately before and after the injection, 5 minutes post-injection, and 15 minutes post-injection. Results: Mean IOP immediately post injection in the study group was 26.71 mmHg, and in the control group was 32.73. The main outcome measure was the area under the curve (AUC)—reflecting the trend of IOP post injection. The AUC was lower in the study group compared to the control group (Mann-Whitney U test, p = 0.046). Conclusions: The use of prophylactic apraclonidine and dorzolamide is effective in modifying the post-injection IOP spike. IOP lowering prophylaxis may be considered in patients with a high baseline IOP.

关键词： Intraocular Pressure Intravitreal Injection Ranibizumab Apraclonidine Dorzolamide

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运城盆地地下水同位素年龄特征及其演化过程和可持续利用

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水文地质工程地质 2012年第6期39卷 1-5页

作者： Matthew Currell 韩冬梅 ian Cartwright 曹国亮宋献方澳大利亚RIMT大学土木环境与化学工程学院中国科学院地理科学与资源研究所陆地水循环及地表过程重点实验室北京100101 澳大利亚莫纳什大学地质科学学院水文地质与环境研究组中国地质大学(北京) 水资源与环境学院北京100083

通过分析运城盆地地下水的碳同位素组成,结合水化学特征,揭示了盆地深层承压地下水的补给期为22～3 ka BP(现代碳百分比(a14C)6～38 pmC)。浅层地下水(71～89 pmC)由现代水或现代水和老水混合组成。深层地下水氢氧同位素组成特征(δ18O... 详细信息

通过分析运城盆地地下水的碳同位素组成,结合水化学特征,揭示了盆地深层承压地下水的补给期为22～3 ka BP(现代碳百分比(a14C)6～38 pmC)。浅层地下水(71～89 pmC)由现代水或现代水和老水混合组成。深层地下水氢氧同位素组成特征(δ18O～-10‰;δ2H～-70‰)表明地下老水在气候较冷的环境下受到补给,而浅层地下水的氢氧同位素组成(δ18O～-8‰;δ2H～-51‰)特征与现代西安降水组成相似。浅层地下水nO3-平均含量(31mg/L)比深层地下水(1.8 mg/L)高,硝酸盐的δ15n-δ18OnO3组成(0‰～5‰)揭示了硝酸盐的主要来源为综合肥料。此外,浅层地下水的TDS由于蒸散发、矿物溶解,可达8.5 g/L(平均2.0 g/L),深层地下老水TDS可达1.8 g/L(平均1.1g/L)水质相对较好。研究区目前主要开采深层地下水,受断裂带影响,浅层地下水已经侵入中深层地下水并与之发生混合,严重影响了中深层地下水的水质。如果发生大规模的浅层地下水与中深层地下水混合,会造成中深层地下老水的nO3-、TDS等含量越来越高。

关键词：运城盆地地下水同位素测年硝酸盐

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The Acute Physiological Effects of the Vaso-Active Drug, L-nnA, a nitric Oxide Synthase Inhibitor, on Renal and Tumour Perfusion in Human Subjects

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Journal of Cancer Therapy 2014年第1期5卷 44-52页

作者： Kent Yip Vicky Goh Jane Gregory ian Simcock J. James Stirling n. Jane Taylor Robert Kozarski Andrew Mitchell Sam Bosopem Gavin Halbert Roberto Alonzi David Miles Peter Hoskin Cancer Centre Mount Vernon Hospital Northwood UK Cancer Research UK Formulation Unit Strathclyde Institute of Pharmacy and Biomedical Sciences University of Strathclyde Glasgow UK Department of Pscyhology University of Hertfordshire College Lane Hertfordshire UK Paul Strickland Scanner Centre Mount Vernon Hospital Northwood UK The Royal Brompton & Harefield nHS Foundation Trust Harefield UK

Purpose: To assess the baseline variation in global renal and tumour blood flow, blood volume and extraction fraction, and changes in these parameters related to the acute physiological effects of a single dose of a non selective inhibitor of nitric oxide synthase, L-nnA. Materials & Methods: Ethical approval and informed consent were obtained for this Phase I clinical study. Patients with advanced solid tumours refractory to conventional therapy were recruited and given L-nnA intravenously at two different dose levels. Volumetric perfusion CT scans were carried out at 1, 24, 48 & 72 hours post L-nnA. Blood pressures were taken at regular interval for 6 hours after LnnA. Results: L-nnA was well tolerated by the four patients who received it. Blood flow (BF) and blood volume (BV) in both tumour and kidney were reduced post L-nnA administration (renal BF—20%;renal BV—19.7%;tumour BF—16.9%;tumour BV—18.6%), though the effect was more sustained in tumour vasculature. A negative correlation was found between the change in systemic blood pressure and vascular supply to the tumour within 1 hour following L-nnA (p 0.0001). Differences in response to L-nnA by separate target lesions in the same patient were observed. Conclusion: The differential effect of L-nnA on tumour and renal blood flow, and the absence of any significant toxicity in this small cohort of patients permit further dose escalation of L-nnA in future early phase trials. The predictive value of blood pressure change in relation to the acute effect of L-nnA on tumour vasculature deserves further evaluation.

关键词： L-nnA Cancer Imaging Vascular Perfusion nitric Oxide

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Adsorption and Reaction of CO on Mo(100)-c(2×2)-n Surface Studied by HREELS

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Chinese Chemical Letters 2000年第3期11卷 275-278页

作者： Jun Fa ZHU.,ian Chang GUO, Run Sheng ZHAI, Xin He BAO, Shu Xian ZHUAnG ( national Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 Department of Chemical Physics. University of Science and Technology of China Univ Sci & Technol China Natl Synchrotron Radiat Lab Hefei 230029 Peoples R China Univ Sci & Technol China Dept Chem Phys Hefei 230026 Peoples R China Chinese Acad Sci Dalian Inst Chem Phys State Key Lab Catalysis Dalian 116023 Peoples R China

High resolution electron energy loss spectroscopy (HREELS) has been used to investigate the adsorption and reaction of CO on the Mo(100)-c(2×2)n surface. CO directly adsorbed on the n atoms from the c(2×2) layer to form isocyanate (nCO) surface species was found in addition to CO adsorbed on the molybdenum atoms at 120 K. indicating that both Mo and n atoms of the Mo(100)-c(2×2)-n surface are of high reactivities for CO adsorption.

关键词： HREELS adsorption reaction Mo(100)-c(2×2)-n CO.

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