检索结果-南通市图书馆

Insect transmission of plant viruses： Multilayered interactions optimize viral propagation

Insect Science 2017年第6期24卷 929-946页

作者： Beatriz Dader Chrstiane Then Edwige Berthelot Marie Ducousso james C. K. ng Martin Drucker InRA UMR 385 BGPI (CIRAD-INRA-SupAgroM) Montpellier France Department of Plant Pathology and Microbiology and Center for Disease Vector Research University of California Riverside USA

By serving as vectors of transmission, insects play a key role in the infection cycle of many plant viruses. Viruses use sophisticated transmission strategies to overcome the spatial barrier separating plants and the impediment imposed by the plant cell wall. Interactions among insect vectors, viruses, and host plants mediate transmission by integrating all organizational levels, from molecules to populations. Best-examined on the molecular scale are two basic transmission modes wherein virus-vector interactions have been well characterized. Whereas association of virus particles with specific sites in the vector＇s mouthparts or in alimentary tract regions immediately posterior to them is required for noncirculative transmission, the cycle of particles through the vector body is necessary for circulative transmission. Virus transmission is also determined by interactions that are associated with changes in vector feeding behaviors and with alterations in plant host＇s morphology and/or metabolism that favor the attraction or deterrence of vectors. A recent concept in virus-host-vector interactions proposes that when vectors land on infected plants, vector elicitors and effectors ＂inform＂ the plants of the confluence of interacting entities and trigger signaling pathways and plant defenses. Simultaneously, the plant responses may also influence virus acquisition and inoculation by vectors. Over- all, a picture is emerging where transmission depends on multilayered virus-vector-host interactions that define the route of a virus through the vector, and on the manipulation of the host and the vector. These interactions guarantee virus propagation until one or more of the interactants undergo changes through evolution or are halted by environmental interventions.

关键词： arbovirus defense host plant insect vector interactions plant virus transmission

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Youth Physical Activity and Enjoyment during Semi-Structured versus Unstructured School Recess

引用

Open Journal of Preventive Medicine 2014年第8期4卷 631-639页

作者： Jessyka n. Larson Timothy A. Brusseau Benjamin Chase Angela Heinemann james C. Hannon Department of Exercise and Sport Science University of Utah Salt Lake City UT USA

Background: Physical activity throughout the school day may help reduce the risk of childhood obesity. Semi-structured recess is a unique approach to create more physical activity. Therefore, the purpose of this study was to compare the physical activity and enjoyment of urban school children during traditional unstructured recess and semi-structured recess. Method: Children from the Southwestern US (n = 165) wore a nL-1000 piezoelectric accelerometer during their 15-minute lunch recess. Children participated in both their traditional unstructured (no structure and no equipment) recess and semi-structured (organized games and equipment) recess. An enjoyment scale was completed after both types of recess formats. Results: During unstructured recess, children accumulated 1028 ± 356 steps and 4.59 ± 2.2 minutes of MVPA compared to 1156 ± 434 steps and 5.44 ± 2.76 minutes of moderate to vigorous physical activity (MVPA) during semi-structured recess. Paired sample t-tests revealed that children took significantly more steps (t = 𕒸.98;p nd MVPA (t = 𕒹.940;p ng semi-structured recess. no significant differences were found for enjoyment (p = 0.847) between recesses. Conclusions: It is important for schools to consider creative, semi-structured recess opportunities to increase step counts and time in MVPA (while maintaining enjoyment) and reinforce recess as an important component of a comprehensive school physical activity program.

关键词： Moderate-to-Vigorous Physical Activity (MVPA) Step Counts Physical Education

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Choice of conodont Idiognathodus simulator （sensu stricto） as the event marker for the base of the global Gzhelian Stage （Upper Pennsylvanian Series, Carboniferous System）

引用

Episodes 2008年第3期31卷 319-325页

作者： Philip H. Heckel Aleksandr S. Alekseev james E. Barrick Darwin R. Boardman natalya V. Goreva Tatiana n. Isakova Tamara I. nemyrovska Katsumi Ueno Elisa Villa David M. Work Department of Geoscience University of Iowa Iowa City Iowa 52242 USA Department of Paleontology Geology Faculty Moscow State University 119992 Moscow Russia Department of Geosciences Texas Tech University Lubbock Texas 79409 USA School of Geology Oklahoma State University Stillwater Oklahoma 74078 USA Geological Institute Russian Academy of Sciences Pyzhevsky per. 7 110017 Moscow Russia Institute of Geological Sciences National Academy of Sciences of Ukraine O. Gonchar Str. 55b 01054 Kiev Ukraine Department of Earth System Science Faculty of Science Fukuoka University Fukuoka 814-0180 Japan Department of Geology University of Oviedo Arias de Velasco s/n 33005 Oviedo Spain Maine State Museum 83 State House Station Augusta Maine 04333 USA

We propose that the level at which the conodont species Idiognathodus simulator （Ellison 1941）（sensu stricto） first appears be selected to mark the base of the Gzhelian Stage, because we believe that this is the optimal level by which this boundary can be correlated. This taxon has a short range and a wide distribution, as shown by correlation of glacial-eustatic cyclothems across the Kasimovian-Gzhelian boundary interval among Midcontinent north America and the Moscow and Donets basins of eastern Europe, based on scale of the cyclothems along with several aspects of biostrati- graphy. Outside of these areas, I. simulator （sensu stricto） is known also from other parts of the U.S., and is reported from the southern Urals and south-central China in its expected position between other widespread taxa. Its first appearance is consistent with the current ammonoid placement of the boundary （first appearance of Shumardites cuyleri）, and it is also compatible with certain aspects of the distribution of Eurasian fusulinid faunas （e.g., lectotype ofRauserites rossicus）.

关键词：牙形石奇颚牙形石属模拟技术岩石学

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Species limits in the Elegant Pitta (Pitta elegans) complex from Wallacea based on bioacoustic and morphometric analysis

引用

Avian Research 2020年第4期11卷 421-432页

作者： Arya Y.Yue Elize Y.X.ng james A.Eaton Frank E.Rheindt Bryn Mawr College Department of Biology101 N Merion AveBryn MawrPA 19010USA Department of Biological Sciences National University of Singapore16 Science Drive 4Singapore 117558Singapore A-3A-5 Casa Indah IPersiaran Surian47810 Petaling JayaMalaysia

Background:The Elegant Pitta(Pitta elegans)complex displays a remarkable diversity of morphological and bioacoustic traits across five taxa currently recognized as *** differ in plumage characteristics(such as red versus black belly patches;supercilium color and extent;and white versus black throats),in lifestyle(resident versus migratory)and in *** investigated the morphological,bioacoustic and ecological differences across all taxa after recent studies demostrated the importance of these traits in recognizing biological species limits across ***:Morphometric analysis was carried out by measuring tarsus,wing,tail and bill lengths of 15 specimens at the natural History Museum,UK,and plumages were inspected across 106 unique individuals from four different *** analysis was based on 134 range-wide sound *** types of calls,territorial calls and alarm calls,were analyzed using different sets of *** component analysis and the Isler Criterion were applied to the *** trials were conducted to explore the levels of response of each taxon to the call types of the other ***:The territorial call of concinna exhibits a distinct two-element motif,while elegans,maria and virginalis utter a three-element motif in which the first two elements are given in quick *** the other hand,vigorsii,produces both two-element and three-element motifs with longer breaks in between *** further corroborated by the playback trials,the three taxa elegans,virginalis and maria form a tight vocal cluster,whereas each concinna and vigorsii are *** alarm call turned out to be less diagnostic even though most taxa did roughly separate into different vocal *** analysis failed to produce strong differences,but plumage distinctions among multiple taxa are ***:We suggest splitting the Elegant Pitta into three biological species based on

关键词： Bioacoustic analysis Elegant Pitta Morphometric analysis Pitta elegans Territorial calls

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Macular carotenoid supplementation improves disability glare performance and dynamics of photostress recovery

引用

Eye and Vision 2016年第1期3卷 231-238页

作者： james M.Stringham Kevin J.O’Brien nicole T.Stringham nutritional neuroscience Laboratory Department of Physiology and PharmacologyUniversity of GeorgiaAthensGA 30602USA Vision Sciences Laboratory Department of PsychologyUniversity of GeorgiaAthensGA 30602USA Interdisciplinary neuroscience Program Biomedical Health Sciences InstituteUniversity of GeorgiaAthensGA 30602USA

Background:The so-called macular carotenoids(MC)lutein(L),zeaxanthin(Z),and meso-zeaxanthin(MZ)comprise the diet-derived macular pigment(MP).The purpose of this study was to determine effects of MC supplementation on the optical density of MP(MPOD),repeated-exposure photostress recovery(PSR),and disability glare(DG)***:This was a double-blind,placebo-controlled ***-nine young(mean age=21.7),healthy volunteers participated in this *** supplemented their daily diet with either 10 mg L+2 mg total Z(1 mg Z+1 mg MZ;n=24),20 mg L+4 mg total Z(2 mg Z+2 mg MZ;n=25),or placebo(n=10)for 12 *** primary outcome was a composite measure of visual performance in glare,defined by change in DG and *** outcomes included MPOD and visual *** primary endpoint for outcomes was 12 *** was assessed with customized heterochromatic flicker *** times for an 8 cycle/degree,15%contrast Gabor patch target were determined after each of five successive exposures to intense LED *** threshold was defined as the intensity of a ring of lights through which subjects were able to maintain visibility of the aforementioned *** of all parameters were conducted at baseline,6 months,and 12 ***-measures AnOVA,and Pearson product-moment correlations were used to determine statistically significant correlations,and changes within and between ***:MPOD for subjects in both supplementation groups increased significantly versus placebo at both 6-and 12-month visits(pnally,PSR times and DG thresholds improved significantly from baseline compared to placebo at 6-and 12-month visits(pne,MPOD was significantly related to both DG thresholds(r=0.444;p=0.0021)and PSR times(r=-0.56;pnction of MPOD,the repeated-exposure PSR curves became more asymptotic,as opposed to *** change in subjects’DG thresholds were significantly related to chang

关键词： Lutein Zeaxanthin Mesozeaxanthin Visual performance Photostress recovery Disability glare Macular pigment Visual cycle

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

道教与生态

引用

作者： n. J. Girardot james Miller 刘笑敢

来源：南通市图书馆图书评论

学校读者我要写书评

暂无评论

Effects of a blend of Saccharomyces cerevisiae-based direct-fed microbial and fermentation products on plasma carbonylmetabolome and fecal bacterial community of beef steers

引用

Journal of Animal Science and Biotechnology 2020年第2期11卷 504-513页

作者： james A.Adeyemi Sunday O.Peters Marcos De Donato Andres Pech Cervantes Ibukun M.Ogunade College of Agriculture Communitiesand the EnvironmentKentucky State UniversityFrankfortKY 40601USA Department of Animal Science Berry CollegeMount BerryGA 30149USA Tecnologico de Monterrey Escuela de Ingenieria y CienciasQueretaroMexico Agricultural Research Station Fort Valley State UniversityFort ValleyGA 31030USA

Background:Previous studies have evaluated the metabolic status of animals fed direct-fed microbial(DFM)using enzyme-based assays which are time-consuming and limited to a few *** addition,little emphasis has been placed on investigating the effects of DFM on hindgut *** examined the effects of dietary supplementation of a blend of Saccharomyces cerevisiae-based DFM and fermentation products on the plasma concentrations of carbonyl-containing metabolites via a metabolomics approach,and fecal bacterial community,via 16S rRnA gene sequencing,of beef steers during a 42-day receiving *** newly weaned steers were randomly assigned to receive a basal diet with no additive(COn;n=20)or a basal diet supplemented with 19 g of Commence™(PROB;n=20)for a 42-day ***™(PMI,Arden Hills,Mn)is a blend of 6.2×1011 cfu/g of ***,3.5×1010 cfu/g of a mixture of Enterococcus lactis,Bacillus subtilis,Enterococcus faecium,and Lactobacillus casei,and the fermentation products of these aforementioned microorganisms and those of Aspergillus oryzae and Aspergillus *** d 0 and 40,rectal fecal samples were collected randomly from 10 steers from each treatment *** d 42,blood was collected for plasma ***:A total number of 812 plasma metabolites were *** to 305 metabolites[fold change(FC)≥1.5,FDR≤0.01]including glucose,hippuric acid,and 5-hydroxykynurenamine were increased by PROB supplementation,whereas 199 metabolites(FC≤0.63,FDR≤0.01)including acetoacetate were *** of PROB increased(P≤0.05)the relative abundance of Prevotellaceae UCG-003,Megasphaera,Dorea,Acetitomaculum,and *** contrast,the relative abundance of Elusimicrobium,Moheibacter,Stenotrophomonas,Comamonas,and uncultured bacterium belonging to family p-2534-18B5 gut group(phylum Bacteroidetes)were reduced(P≤0.05).Conclusions:The results of this study demonstrated that supplementation of PROB altered both the plasma carbonyl metab

关键词： Beef steer Carbonyl Fecal bacteria Lactate-utilizing bacteria Plasma metabolomics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

structures:new solutions and uncommon characteristics james Kirby,Shiwei Zhou,

引用

Acta Mechanica Sinica 2022年第6期38卷 128-140,I0003页

作者： james Kirby Shiwei Zhou Yi Min Xie Centre for Innovative Structures and Materials School of EngineeringRMIT UniversityMelbourne 3001Australia

To investigate the characteristics of optimal fail-safe structures subjected to single and multi-member damage scenarios,we con-sider a pin-jointed cantilever truss with all members directly connected from the load point to the *** problem formu-lations are considered—minimizing the compliance with a volume constraint and minimizing the volume with stress *** these formulations produce equivalent structures for traditional truss design problems,we find that this is not always the case in the fail-safe *** solutions are developed for a three-bar truss under both problem *** is modelled as the complete removal of any one member,and a minmax problem is constructed to minimize the compliance or volume of the structure for the worst-case damage *** new analytical solutions provide much needed benchmarks for numerical fail-safe *** problems are extended to n-bar systems with damage to multiple *** show that as the structural complexity(the number of members in a system)increases,the optimum fail-safe structure tends towards a variation of the nominal two-bar design with overlapping *** these observations,we then approach the idea of full redundancy through the introduction of parallel substructures into a more complex truss *** compare our fully redundant truss design with a benchmark fail-safe solution and show that the fully redundant design has significantly better performance and with fewer ***,this suggests that fully redundant structural designs are highly efficient and have the additional benefit of only requiring the computation of the nominal solution.

关键词： Fail-safe optimization Minimum compliance Minimum volume,

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma-Induced Interfacial Processes in Metal Halides FTIR Gas Cell Windows

引用

Journal of Analysis and Testing 2023年第4期7卷 392-404页

作者： Jaka Olenik Vasyl Shvalya Martina Modic Jernej Ekar Janez Kovac Uros Cvelbar james L.Walsh York Plasma Institute School of PhysicsEngineering and TechnologyUniversity of YorkYork YO105DDUK Department for Gaseous Electronics F6 Jozef Stefan Institute1000 LjubljanaSlovenia Department of Surface Engineering F4 Jozef Stefan Institute1000 LjubljanaSlovenia Jozef Stefan International Postgraduate School 1000 LjubljanaSlovenia

Fourier transform infrared spectroscopy(FTIR)is one of the most widely used vibrational diagnostic techniques to investigate gas-phase reactive oxygen and nitrogen species(ROnS).However,the technique carries intrinsic challenges,particularly in relation to interfering peaks in the spectral *** study explores the interfacial processes that occur when reactive oxygen and nitrogen species generated by a non-equilibrium air plasma interact with the metal halide windows of an FTIR gas cell,leading to the appearance and evolution of spurious absorption peaks which complicate spectral *** spectroscopy,X-ray photoelectron spectroscopy,time of flight secondary ion mass spectrometry and attenuated total reflectance-FTIR spectroscopy were used to elucidate the origin of spurious absorption peaks spanning the 1400-1300 cm^(-1)spectral range as a result of KBr exposure to plasma generated *** was found that plasma exposed KBr contained a lower atomic fraction of Br which was replaced by the nO3nitrate group,the main absorbance peak of which progressively evolved with plasma exposure and affected the window transparency over the corresponding FTIR region.A correlation was revealed between KnO_(3)formation,plasma power and exposure time to a growth and change in molecular vibrational energies corresponding to asymmetric nO3stretching vibrations in the KnO_(3)structure.

关键词： Cold atmospheric-pressure plasma Gas-phase FTIR ROnS IR windows Surface functionalisation KBr

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Increasing Visitor Knowledge of Park History and natural Resources via non-Traditional Recreation: An Exploratory Study of Quicksand Enthusiasts

引用

natural Resources 2019年第9期10卷 358-366页

作者： Charles K. Mullins Michael J. Bradley Lashé D. Mullins james n. Maples Division of Humanities and Social Sciences Alice Lloyd College Pippa Passes USA Department of Recreation and Park Administration Eastern Kentucky University Richmond USA Department of Anthropology Sociology and Social Work Eastern Kentucky University Richmond USA

Sinkers are quicksand enthusiasts that crave the sensation of being trapped in deep mud while being sucked downward. Although humans have been interested in quicksand over the years (particularly through film), there remains a void of research into the meaning and value in the lives of those who engage in a recreational pursuit of quicksand, most notably the community of individuals who self-describe as sinkers. The purpose of this exploratory study was to examine if sinking can contribute to a participant’s understanding of history and natural resources at state parks. In order to obtain a better understanding of the effects, a qualitative study was conducted in the summer of 2016 at Stephen C. Foster State Park, a state park adjacent to Okefenokee Swamp. The researchers exercised grounded theory techniques and inductive content analysis to analyze interview data and compile coded text into four main categories: learning, enjoyment, traveling, and economic impact. Findings suggest that participants believed their knowledge of park history and natural resources increased through a recreational pursuit of quicksand.

关键词： Quicksand Sinkers Sinking Qualitative Research Park Management History natural Resources

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：