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Growth at the microscale:long term thinning effects on patterns and timing of intra-annual stem increment in radiata pine

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Forest Ecosystems 2018年第4期5卷 438-450页

作者： david M.drew Geoffrey M.Downes Department of Forest and Wood Science Stellenbosch UniversityPrivate Bag X1Matieland 7800South Africa Forest Quality Pty Ltd PO Box 293 HuonvilleTASAustralia.

Background: Stem radial growth in forests is not uniform. Rather, it is characterized by periods of relatively fast or slow growth, or sometimes no growth at all. These fluctuations are generally a function of varying environmental conditions(e.g. water availability) and, importantly, will also be associated with adjustments in proprties in the wood formed. Stand level conditions and forest management, particularly thinning and stand density will, thowever, also have a major influence on patterns of growth variation. We explore how different thinning histories and/or stand densities influence these dynamics of tree growth in the important commercial plantation species Pinus radiata D. ***: Daily stem size change was measured using electronic point dendrometers over two growing seasons on P. radiata trees at two sites, subjected to different thinning regimes. Timing, rates and periodicity of annual growth were calculated from these ***: Greater overall cross-sectional growth in thinned plots was driven mainly by two dynamics. First, the cessation of seasonal growth occurred at least 3 weeks later in the stands in which thinning had taken place. There was no difference between thinned/unthinned stands, however, in the timing of growth onset. Second, within the longer season, trees in thinned plots had more growth days(as much as 20% more) than unthinned plots. The rates of growth on days when growth occurred were not different, however. In this context, it is notable that in trees in the unthinned plots experiencing the most severe competition there were strong "pulses" of growth following drought-breaking rainfall events. Unthinned plots at high stand densities also maintained a smaller(but consistent) zone of dividing cells throughout the season than thinned ***: In Pinus radiata growing under conditions as in our study, conditions late in summer, particularly drought, have an important effect on the timing of cessation of growth. Earl

关键词： Monterey pine Dendrometer Intra-annual growth Drought Thinning

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Diversity and production in an Afromontane Forest

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Forest Ecosystems 2016年第4期3卷 275-286页

作者： Klaus v.Gadow GongQiao Zhang Graham Durrheim david drew Armin Seydack Georg-August University in Gottingen Gottingen Germany Department of Forestry and Wood Science University of Stellenbosch Stellenbosch South Africa Chinese Academy of Forestry in Beijing Beijing China South African National Parks Knysna South Africa

Background：This contribution evaluates the effect of forest structure and tree species diversity on plot productivity and individual tree growth in the unique Knysna forests in Southern Africa using mapped tree data from an observational study that has been re-measured over a period of 40 ***：The effects of tree species diversity and forest structure on tree growth and forest production are evaluated on three levels of resolution：a） the forest community（canopy,sub-canopy species）,b） the subplots（number of trees per ha,skewness of the diameter distribution,diameter coefficient of variation） and c） the immediate neighborhood of selected reference trees（＂Mingling＂,＂Dominance＂,Aggregation＂ and ＂Size Variation＂）.Results：An analysis of the community level identified two distinct clusters,one including dominant/canopy species with the highest growth rates and a greater variation of growth,and another cluster which includes the remaining subcanopy species which have a smaller maximum size and lower rates of *** area-based structure variables on plot level have a highly significant effect on total basal area ***,the effects of forest density and species richness on productivity were not straight *** basal area production of about 0.75 m^2/ha/year is achieved at medium levels of richness（around 20 species per ha） and medium levels of density（around 30 m^2/ha basal area） using percentile regression *** relative ＂Dominance＂ of a selected reference tree had a highly significant effect on individual tree growth on all investigated *** neighbourhood structure variables were only occasionally significant or not significant at ***：This contribution presents a new theoretical framework for analysing natural forests that includes community,plot and neighborhood variables of forest structure and diversity,and a first specific analysis of the structure and dynamics of the Knysna Afromontane Forest,based on a unique s

关键词： canopy neighborhood forests richness basal straight productivity occasionally remaining tropical

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Injury and illness in short-course triathletes:A systematic review

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Journal of Sport and Health Science 2024年第2期13卷 172-185页

作者： Sara A.Guevara Melissa L.Crunkhorn Michael drew Gordon Waddington Julien D.Périard Naroa Etxebarria Liam A.Toohey Paula Charlton University of Canberra Research Institute for Sport and Exercise(UCRISE) BruceACT 2617Australia New South Wales Institute of Sport SydneyNSW 2127Australia Queensland Academy of Sport BrisbaneQLD 4111Australia Triathlon Australia Gold CoastQLD 4227Australia Australian Institute of Sport BruceACT 2617Australia

Background:Determining the incidence and prevalence of injury and illness in short-course triathletes would improve understanding of their etiologies and therefore assist in the development and implementation of prevention *** study synthesizes the existing evidence on the incidence and prevalence of injury and illness and summarizes reported injury or illness etiology and risk factors affecting short-course ***:This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses *** reporting health problems(injury and illness)in triathletes(all sexes,ages,and experience levels)training and/or competing in short-course distances were *** electronic databases(Cochrane Central Register of Controlled Trials,MEDLINE,Embase,APA PsychINFO,Web of Science Core Collection,and SPORTDiscus)were *** of bias was independently assessed by 2 reviewers using the Newcastle-Ottawa Quality Assessment *** authors independently completed data ***:The search yielded 7998 studies,with 42 studies eligible for ***-three studies investigated injuries,24 studies investigated illnesses,and 5 studies investigated both injuries and *** injury incidence rate ranged 15.7-24.3 per 1000 athlete exposures,and the illness incidence rate ranged 1.8-13.1 per 1000 athlete *** and illness prevalence ranged between 2%-15%and 6%-84%,*** injuries reported occurred during running(45%-92%),and the most frequently reported illnesses affected the gastrointestinal(7%-70%),cardiovascular(14%-59%),and respiratory systems(5%-60%).Conclusion:The most frequently reported health problems in short-course triathletes were:overuse and lower limb injuries associated with running;gastrointestinal illnesses and altered cardiac function,primarily attributable to environmental factors;and respiratory illness mostly caused by infection.

关键词： Athlete illnesses Athletic injuries Epidemiology Triathlon

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Highly efficient fiber to Si waveguide free-form coupler for foundry-scale silicon photonics

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Photonics Research 2024年第5期12卷 1055-1066页

作者： LUIGI RANNO JIA Xu BRIAN SIA COSMIN POPESCU drew WENINGER SAMUEL SERNA SHAOLIANG YU LIONEL C.KIMERLING ANURADHA AGARWAL TIAN GU JUEJUN HU Department of Materials Science&Engineering Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA Centre for Micro-&Nano-Electronics(CMNE) Nanyang Technological UniversitySingapore 639798Singapore Department of Physics Photonics and Optical EngineeringBridgewater State UniversityBridgewaterMassachusetts 02324USA Zhejiang Laboratory Hangzhou 311100China Materials Research Laboratory Massachusetts Institute of TechnologyCambridgeMassachusetts 02139USA

As silicon photonics transitions from research to commercial deployment,packaging solutions that efficiently couple light into highly compact and functional sub-micrometer silicon waveguides are imperative but remain *** 220 nm silicon-on-insulator(SOI)platform,poised to enable large-scale integration,is the most widely adopted by foundries,resulting in established fabrication processes and extensive photonic component *** development of a highly efficient,scalable,and broadband coupling scheme for this platform is therefore of paramount *** two-photon polymerization(TPP)and a deterministic free-form micro-optics design methodology based on the Fermat’s principle,this work demonstrates an ultraefficient and broadband 3-D coupler interface between standard SMF-28 single-mode fibers and silicon waveguides on the 220 nm SOI *** coupler achieves a low coupling loss of 0.8 dB for the fundamental TE mode,along with 1 dB bandwidth exceeding 180 *** broadband operation enables diverse bandwidthdriven applications ranging from communications to ***,the 3-D free-form coupler also enables large tolerance to fiber misalignments and manufacturing variability,thereby relaxing packaging requirements toward cost reduction capitalizing on standard electronic packaging process flows.

关键词： fiber waveguide enable

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Molecular phylogeny and taxonomy of Phlomoides(Lamiaceae subfamily Lamioideae)in China:Insights from molecular and morphological data

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Plant Diversity 2024年第4期46卷 462-475页

作者： Yue Zhao Ya-Ping Chen Bryan T.drew Fei Zhao Maryam Almasi Orzimat T.Turginov Jin-Fei Xiao Abdul G.Karimi Yasaman Salmaki Xiang-Qin Yu Chun-Lei Xiang CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau&Inner Mongolia Key Laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010000Inner MongoliaChina Department of Biology University of Nebraska at KearneyKearneyNE 68849USA CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chinese Academy of SciencesChengdu Institute of BiologyChengdu 610042SichuanChina Center of Excellence in Phylogeny of Living Organisms Department of Plant ScienceCollege of ScienceUniversity of TehranP.O.Box 14155-6455TehranIran Institute of Botany Academy of Sciences of the Republic of UzbekistanTashkent 100047Uzbekistan Faculty of Biology Department of Botany and Plant PhysiologyNational University of Uzbekistan named after Mirzo UlugbekTashkent 100174Uzbekistan Faculty of Pharmacy Kabul University1006 KabulAfghanistan

Phlomoides,with 150-170 species,is the second largest and perhaps most taxonomically challenging genus within the subfamily Lamioideae(Lamiaceae).With about 60 species,China is one of three major biodiversity centers of *** some Phlomoides species from China have been included in previous molecular phylogenetic studies,a robust and broad phylogeny of this lineage has yet to be ***,given the myriad new additions to the genus,the existing infrageneric classification needs to be evaluated and ***,we combine molecular and morphological data to investigate relationships within Phlomoides,with a focus on Chinese *** observed that plastid DNA sequences can resolve relationships within Phlomoides better than nuclear ribosomal internal and external transcribed spacer regions(nrITS and nrETS).Molecular phylogenetic analyses confirm the monophyly of Phlomoides,but most previously defined infrageneric groups are not *** addition,morphological analysis demonstrates the significant taxonomic value of eight characters to the *** on our molecular phylogenetic analyses and morphological data,we establish a novel section Notochaete within Phlomoides,and propose three new combinations as well as three new *** study presents the first molecular phylogenetic analyses of Phlomoides in which taxa representative of the entire genus are included,and highlights the phylogenetic and taxonomic value of several morphological characters from species of Phlomoides from *** study suggests that a taxonomic revision and reclassification for the entire genus is necessary in the future.

关键词： Lamioideae Molecular phylogenetics Morphology Phlomideae Taxonomy

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Biomechanics associated with tibial stress fracture in runners:A systematic review and meta-analysis

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Journal of Sport and Health Science 2023年第3期12卷 333-342页

作者： Clare E.Milner Eric Foch Joseph M.Gonzales drew Petersen Department of Physical Therapy and Rehabilitation Sciences Drexel UniversityPhiladelphiaPA 19102USA Department of Health Sciences Central Washington UniversityEllensburgWA 98926USA

Background:Tibial stress fracture(TSF)is an overuse running injury with a long recovery *** many running studies refer to biomechanical risk factors for TSF,only a few have compared biomechanics in runners with TSF to *** aim of this systematic review and meta-analysis was to evaluate biomechanics in runners with TSF compared to ***:Electronic databases PubMed,Web of Science,SPORTDiscus,Scopus,Cochrane,and CINAHL were *** of bias was assessed and meta-analysis conducted for variables reported in 3 or more ***:The search retrieved 359 unique records,but only the 14 that compared runners with TSF to controls were included in the *** studies were retrospective,2 were prospective,and most had a small sample size(5-30 per group).Many variables were not significantly different between ***-analysis of peak impact,active,and braking ground reaction forces found no significant differences between *** studies found larger tibial peak anterior tensile stress,peak posterior compressive stress,peak axial acceleration,peak rearfoot eversion,and hip adduction in the TSF ***:Meta-analysis indicated that discrete ground reaction force variables were not statistically significantly different in runners with TSF compared to *** individual included studies,many biomechanical variables were not statistically significantly different between ***,many were reported by only a single study,and sample sizes were *** encourage additional studies with larger sample sizes of runners with TSF and controls and adequate statistical power to confirm or refute these findings.

关键词： Bone stress injury Gait Kinematics Kinetics Tibial acceleration

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Integrative filtration research and sustainable nanotechnology

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Particuology 2013年第1期11卷 5-13页

作者： Jing Wang drew Thompson david Y.H.Pui Institute of Environmental Engineering ETH Zurich 8093Switzerland Analytical Chemistry Empa8600 DubendorfSwitzerland Particle Technology Laboratory University of Minnesota55455USA

With the wide applications of nanomaterials in an array of industries, more concerns are being raised about the occupational health and safety of nanoparticles in the workplace, and implications ofnanotech- nology on the environment and living systems. Studies on environmental, health and safety （EHS） issues of nanomaterials play a significant role in public acceptance, and eventual sustainability, of nanotechnol- ogy. We present research results on three aspects of the EHS studies： characterization and measurement of nanoparticles, nanoparticle emission and exposure at workplaces, and control and abatement of nanoparticle release using filtration technology. Measurement of nanoparticle agglomerates using a newly developed instrument, the Universal Nanoparticle Analyzer, is discussed. Nanoparticle emission and exposure measurement results for carbon nanotubes in the manufacture of nanocomposites and for silicon nanoparticles in their production at a pilot scale facility are presented. Filtration of nanoparticles and nanoparticle agglomerates are also studied.

关键词： Agglomerate Sustainability Exposure Filtration Nano-EHS Nanoparticle

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Field testing innovative differential geospatial and photogrammetric monitoring technologiesin mountainous terrain near Ashcroft,British Columbia,Canada

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Journal of Mountain Science 2021年第1期18卷 1-20页

作者： david HUNTLEY Peter BOBROWSKY Roger MACLEOD Robert COCKING Jamel JOSEPH drew ROTHERAM-CLARKE Geological Survey of Canada 1500-605 Robson StreetVancouverBritish ColumbiaV6B 5J3Canada Geological Survey of Canada 9860 West Saanich RoadSidneyBritish ColumbiaV8L 4B2Canada

This paper presents a novel approach to continuously monitor very slow-moving translational landslides in mountainous terrain using conventional and experimental differential global navigation satellite system(d-GNSS)technologies.A key research question addressed is whether displacement trends captured by a radio-frequency“mobile”d-GNSS network compare with the spatial and temporal patterns in activity indicated by satellite interferometric synthetic aperture radar(InSAR)and unmanned aerial vehicle(UAV)*** testing undertaken at Ripley Landslide,near Ashcroft in south-central British Columbia,Canada,demonstrates the applicability of new geospatial technologies to monitoring ground control points(GCPs)and railway infrastructure on a landslide with small and slow annual displacements(<10 cm/yr).Each technique records increased landslide activity and ground displacement in late winter and early *** this interval,river and groundwater levels are at their lowest levels,while ground saturation rapidly increases in response to the thawing of surficial earth materials,and the infiltration of snowmelt and runoff occurs by way of deep-penetrating tension cracks at the head scarp and across the main slide *** over the last decade provides vital information for government agencies,national railway companies,and other stakeholders to understand geohazard risk,predict landslide movement,improve the safety,security,and resilience of Canada’s transportation infrastructure;and reduce risks to the economy,environment,natural resources,and public safety.

关键词： Landslide Change detection monitoring Global Navigation Satellite System Real-Time Kinematic System GeocubeTM Bathymetric Survey Unmanned Aerial Vehicle Interferometric Synthetic Aperture Radar

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Cover Crop and Irrigation Effects on Soil Microbial Communities and Enzymes in Semiarid Agroecosystems of the Central Great Plains of North America

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Pedosphere 2016年第2期26卷 192-205页

作者： Francisco J. CALDERON david NIELSEN Veronica ACOSTA-MARTINEZ Merle F. VIGIL drew LYON USDA-ARS Central Great Plains Research Station Akron CO 80720 USA USDA-ARS Cropping Systems Research Laboratory Wind Erosion and Water Conservation Unit Lubbock TX 79415 USA Department of Crop and Soil Sciences Washington State University Pullman WA 99164-6420 USA

盖子庄稼能由增加碳(C) 供应在土壤微生物学上有有益的效果，但是这些有益的效果能被降水条件调制。这研究的目的是比较休闲冬季小麦(Triticum aestivum L.) 旋转到在在半干旱的美国高平原的 rainfed 和灌溉条件下面的几盖子庄稼冬季小... 详细信息

盖子庄稼能由增加碳(C) 供应在土壤微生物学上有有益的效果，但是这些有益的效果能被降水条件调制。这研究的目的是比较休闲冬季小麦(Triticum aestivum L.) 旋转到在在半干旱的美国高平原的 rainfed 和灌溉条件下面的几盖子庄稼冬季小麦旋转。实验在科罗拉多在二个地点，在内布拉斯加的 Sidney，和 Akron 被执行，美国与三次在在盖子庄稼结束的 2012-2013 的土壤采样，种的小麦，和小麦成熟。实验包括了四单个种类的盖子庄稼， 10 种类混合物，和一个休闲处理。测量的变量是土壤 C 和氮(N) ，由甲基酉旨(名声) 介绍的丰满的酸的土壤社区结构，和土壤 -glucosidase,-glucosaminidase, 和 phosphodiesterase 活动。休闲处理，缺乏生活植物，在盖子庄稼结束减少了大多数名声的集中。全部的名声集中与盖子庄稼生物资源被相关(R = 0.62 在 Sidney 并且 0.44 在 Akron ) 。等到种的小麦，有灌溉的有益的效果，它在 mycorrhizal 和原生动物门标记引起了增加。在小麦成熟，土壤名声上的盖子庄稼和灌溉效果减退了，但是灌溉在 Akron 在 -glucosidase 和 phosphodiesterase 活动上有积极效果，它二个地点中是更干燥的。盖子庄稼和灌溉是慢的影响土壤 C 集中。我们的结果证明盖子庄稼在在半干旱的基于小麦的旋转和灌溉的微生物引起的社区能提高的土壤上有短命效果土壤酶活动。在半干旱的环境，更长的时间跨度可能被需要在土壤上看见盖子庄稼的有益的效果微生物引起的社区结构，土壤酶活动，和土壤 C 隐遁。

关键词：土壤微生物群落覆盖作物灌溉条件酯酶活性美国平原 β-葡萄糖苷酶微生物群落结构

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2023年诺贝尔生理学或医学奖简介

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解剖学报 2024年第1期55卷 1-2页

作者： Katalin Karik drew Weissman 陈至鑫(编译) 曾武威(审校) 章静波(审校) 匈牙利塞格德(Szeged)大学美国宾夕法尼亚大学宾夕法尼亚RNA创新研究所北京大学国际医院中国医学科学院基础医学研究所

2023年诺贝尔生理学或医学奖授予两位科学家Katalin Kariko和drew Weissman,以表彰他们对于核苷碱基修饰的发现,从而使得开发针对新型冠状病毒肺炎(corona virus disease 2019,COVID-19)的有效mRNA疫苗成为可能。两位诺贝尔奖获得者的... 详细信息

2023年诺贝尔生理学或医学奖授予两位科学家Katalin Kariko和drew Weissman,以表彰他们对于核苷碱基修饰的发现,从而使得开发针对新型冠状病毒肺炎(corona virus disease 2019,COVID-19)的有效mRNA疫苗成为可能。两位诺贝尔奖获得者的发现对于开发针对在2020年初开始流行的COVID-19的有效mRNA疫苗起到了至关重要的作用。他们的突破性发现从根本上改变了我们对mRNA如何与机体免疫系统相互作用的理解,获奖者在现代人类健康面临最大威胁之一的关键性时刻,为疫苗开发做出了前所未有的杰出贡献。

关键词：机体免疫系统诺贝尔生理学或医学奖疫苗开发碱基修饰诺贝尔奖获得者

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