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Spatial Distribution of Mountain Pine Beetle Outbreaks in Relation to Climate and Stand Characteristics： A Dendroecological Analysis

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Journal of Integrative Plant Biology 2007年第2期49卷 168-178页

作者： Elizabeth M. Campbell René I. Alfaro Brad hawkes Canadian Forest Service Pacific Forestry Centre Victoria BC Canada V8Z 1M5

Principal components analysis, followed by K-means cluster analysis, was used to detect variations in the timing and magnitude of Pinus contorta Dough ex Loud. growth releases attributed to mountain pine beetle outbreaks in 31 stands of central British Columbia. Four major growth release patterns were identified from 1970 to 2000. Variations in the timing of growth releases among clustered stands corresponded well to aerial survey data indicating the timing of beetle outbreaks in the study area. Redundancy analysis was used to determine how variations in the timing and magnitude of growth releases attributed to beetle outbreaks changed with variations in climate or stand conditions over the study area. The first RDA axis, which accounted for 39% of the variations in growth patterns among stands, was significantly （P〈0.05） correlated with gradients in the percentage of pine in stands killed by mountain pine beetle, summer aridity, variation in summer precipitation, distance from initial infestation site, average pine age, and maximum August temperatures. The second RDA axis explained 6% of the variations and was significantly correlated with gradients in the beetle climate suitability index, extreme cold month temperatures, and site index. Comparisons of growth release patterns with aerial survey data and redundancy analyses indicated that dendrochronological techniques are useful for identifying mountain pine beetle outbreaks in central British Columbia, particularly among stands that had a density high enough to produce a growth release signal. Provided future studies account for interannual weather fluctuations, identification of growth increases due to stand thinning caused by beetle outbreaks will be useful for reconstructing the history of beetle outbreaks over much longer time periods.

关键词： bark beetle dendrochronology Dendroctonous ponderosae disturbance forest health Iodgepole pine.

A randomized,fellow eye,comparison of keratometry,aberrometry,tear film,axial length and the anterior chamber depth after eye rubbing in non-keratoconic eyes

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Eye and Vision 2017年第1期4卷 106-113页

作者： Jordan V.Chervenkoff Elizabeth hawkes Gabriela Ortiz Deborah Horney Mayank A.Nanavaty Sussex Eye Hospital Brighton&Sussex University Hospitals NHS TrustEastern RoadBrighton BN25BFUK

Background:To investigate the effect of eye rubbing on keratometry(K),aberrometry,tear film break-up-time(TFBUT)and anterior chamber depth(ACD).Methods:Volunteers without any corneal pathology or dry eyes were randomised to rubbing in one eye and the fellow-eye was *** rubbing was performed for 2 *** outcomes studied were anterior and posterior K *** outcomes were changes in TFBUT,axial length(AL)&ACD,K changes in various zones,asphericity and *** and post rubbing K,aberrometry,ACD and TFBUT were assessed in a predetermined *** relationship of the above parameters to axial length(AL)was also *** was analysed using vector ***:Pre versus post rubbing,anterior flatter K further flattened(42.51±1.52 D vs.42.36±1.53 D,p=0.003)and the changes to J0 vector in central cornea(−0.16±0.26 D vs.-0.27±0.33 D,p=0.038)suggested change to against-the-rule(ATR)*** was significant change in Z^(+2)_(2) polynomial following *** found a positive correlation between axial length and change in posterior K(r=0.335,p=0.020).The TFBUT reduced following eye rubbing(15.3 s vs.13.9 s,p=0.0001).There was a positive correlation between AL and increase in ACD post rubbing(r=0.300,p=0.038).There was a positive correlation between ACD and change in mean posterior K(r=0.305,p=0.035).Conclusions:In healthy eyes,following eye rubbing,there is a significant change in TFBUT and central anterior K changes towards ATR *** eyes had more changes in posterior K and ***,eyes with deeper ACD showed more steepness of posterior K.

关键词： Eye rubbing Ectasia Tear film break up time Astigmatism Aberrations

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社交媒体可早期警示病毒暴发

英国医学杂志中文版 2016年第2期19卷 70-71页

作者： Nigel hawkes 马岩伦敦北京协和医学院卫生部老年医学研究所

英国食品标准局（FSA）资助的一个项目发现，根据那些生病的推特（Twitter）客在推特上的标签追踪到诺如病毒（noro virus）暴发。

关键词：社交媒体病毒治疗方法医学研究

批评人士指出:美国每年为治疗干眼症投入20亿美元让人“热泪盈眶”

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英国医学杂志中文版 2019年第3期22卷 135-136页

作者： Nigel hawkes 潘澄(译) 不详中华医学会党群办公室

JAMA Internal Medicine 杂志的_篇文章指出,美国每年花费超过20亿美元(14亿英镑,16亿欧元)在一种疗效有限的药物上,该药物的适用病症甚至不被认为是一种疾病.新罕布什尔州达特茅斯卫生政策研究所(Institute for Health Policyat Dartmo... 详细信息

JAMA Internal Medicine 杂志的_篇文章指出,美国每年花费超过20亿美元(14亿英镑,16亿欧元)在一种疗效有限的药物上,该药物的适用病症甚至不被认为是一种疾病.新罕布什尔州达特茅斯卫生政策研究所(Institute for Health Policyat Dartmouth, New Hampshire)的 LisaSchwartz 和 Stephen Woloshin 认为,由美国艾尔建(Allergan)公司研制的治疗干眼病药物丽眼达(Restasis),虽然已通过美国食品与药品监督管理局(FDA)审批,但其临床应用证据不足,其使用更多的是积极营销的结果。

关键词：美国治疗干眼症药品监督管理局卫生政策适用病症临床应用药物

Using Task Repetition to Direct Learner Attention and Focus on Form

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基础教育外语教学研究 2012年第8期 29-36页

作者： Martin L. hawkes

尽管近年来一些教师和学者对任务型教学（TBLT：Task—BasedLanguageTeaching）情有独钟，他们也开始关注这种教学方法对外语教学是否有效，但强势任务型不关注语言的现象普遍存在，实际上无论强势或弱势任务型都更多地关注做事的结果... 详细信息

尽管近年来一些教师和学者对任务型教学（TBLT：Task—BasedLanguageTeaching）情有独钟，他们也开始关注这种教学方法对外语教学是否有效，但强势任务型不关注语言的现象普遍存在，实际上无论强势或弱势任务型都更多地关注做事的结果，这类方法往往颠倒语言学习过程。本文作者试图在教师采用任务型的基础上做出纠正，指出任务重复可使学生聚焦语言形式，是教师实施任务型教学效果不佳的补救。然而，这种纠正或补救不仅仍然颠倒了教学过程，仍然采用先用后学的策略，违背了二语习得理论中的输入输出学说，很难应用于外语教学类型的语言课堂。广大读者在阅读中可仔细品味语言学习和语言使用这两个过程，孰先孰后更合理，怎样才能提高外语教学效率。

关键词：基础教育英语教学方法教材

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乳腺癌筛查错误:塞翁失马,焉知祸福

英国医学杂志中文版 2019年第2期22卷 78-79页

作者： Nigel hawkes 曹磊(译) 伦敦北京协和医院胸外科

上周,一组老年妇女被发现错过了乳腺钼靶筛查。Nigelhawkes带来标题背后的故事。

关键词：筛查乳腺癌乳腺钼靶

全科医生诊疗行为的追踪系统提示可节省的成本

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英国医学杂志中文版 2017年第3期20卷 124-125页

作者： Nigel hawkes 应美珂任菁菁伦敦浙江大学第一附属医院全科医学科

一种新的分析工具能比较全科医疗与其他医疗对于相似患病群体的临床诊疗行为，以发现诊疗差别有多大并告知改进方式。

关键词：跟踪显示成本性能

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在线反思性交互的评估

开放教育研究 2004年第5期10卷 23-25页

作者： Mark hawkes Terry Dennis 熊秋娥项国雄美国南达科他州州立大学教育学院江西师范大学传播学院

交互是在线学习的关键要素,同(异)步交互工具可拓展教学交互的深度与广度,而科学、有效的评估能促进交互。本文在比较多种异步交互评估方法后,以建构主义学习理论为基础,引用Simmons的反思性思维评价量规,详尽地描述了反思性交互的激励... 详细信息

交互是在线学习的关键要素,同(异)步交互工具可拓展教学交互的深度与广度,而科学、有效的评估能促进交互。本文在比较多种异步交互评估方法后,以建构主义学习理论为基础,引用Simmons的反思性思维评价量规,详尽地描述了反思性交互的激励式评估在案例中的实施过程。

关键词：在线学习交互评估反思性思维激励机制网络教育

Intraspecific variation in precipitation responses of a widespread C_(4) grass depends on site water limitation

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Journal of Plant Ecology 2017年第2期10卷 310-321页

作者： Michael J.Aspinwall Philip A.Fay Christine V.hawkes David B.Lowry Albina Khasanova Jason Bonnette Briana K.Whitaker Nicholas Johnson Thomas E.Juenger hawkesbury Institute for the Environment Western Sydney UniversityHawkesbury CampusLocked Bag 1797PenrithNew South Wales 2751Australia USDA-ARS Grassland Soil and Water Research Laboratory 808 East Blackland RdTempleTX 76502USA Department of Integrative Biology University of Texas at Austin1 University StationAustinTX 78712USA Department of Plant Biology Michigan State University612 Wilson RoadEast LansingMI 48824USA

Aims Variation in precipitation strongly influences plant growth,species distributions and genetic *** variation in pheno-typic plasticity,the ability of a genotype to alter its growth,morphol-ogy or physiology in response to the environment,could influence species responses to changing precipitation and climate *** this,the patterns and mechanisms of intraspecific varia-tion in plasticity to variable precipitation,and the degree to which genotype responses to precipitation are influenced by variation in edaphic conditions,remain poorly ***,we determined whether genotypes of a widespread C_(4) grass(Panicum virgatum L.,switchgrass)varied in aboveground productivity in response to changes in precipitation,and if site edaphic conditions modified genotype aboveground productivity responses to *** also determined if genotype productivity responses to precipitation are related to plasticity in underlying growth and phenological *** Nine *** genotypes originating from an aridity gradient were grown under four treatments spanning the 10th to the 90th percentiles of annual precipitation at two sites in central Texas:one site with deep,fine-textured soils and another site with shallow,coarse-textured *** measured volumetric soil water content(VWC),aboveground net primary productivity(ANPP),tiller pro-duction(tiller number),average tiller mass,canopy height,leaf area index(LAi)and flowering time on all plants at both sites and examined genotype responses to changes in *** Findings Across precipitation treatments,VWC was 39%lower and more variable at the site with shallow,coarse-textured soils compared to the site with deep,fine-textured *** averaged across genotypes and precipita-tion treatments was also 103%higher at the site with deep,fine-textured soils relative to the site with shallow,coarse-textured soils,indicating substantial differences in site water limitation.W

关键词： climate change Panicum virgatum phenology phenotypic plasticity precipitation