检索结果-南通市图书馆

Abundance and prey capture success of Common Terns(Sterna hirundo)and Pied Kingfishers(Ceryle rudis)in relation to water clarity in south-east coastal Ghana

引用

Avian Research 2018年第3期9卷 226-238页

作者： Lars h.holbech Francis Gbogbo Timothy Khan Aikins Department of Animal Biology and Conservation Science University of GhanaP.O.Box LG 67LegonAccraGhana Department of Biodiversity Conservation and Management University for Development StudiesBox TL 1882Nyankpala CampusTamaleGhana

Background: water clarity may negatively influence rate of plunge diving and prey capture success of piscivorous plunge-diving birds, and therefore has implications for their conservation in polluted urban wetlands. we studied the relationship between water clarity and the abundance and prey capture success of Pied Kingfishers(Ceryle rudis) and Common Terns(Sterna hirundo) in two polluted coastal waters of south-east Ghana—the weija Lake and Densu Delta Ramsar ***: On each wetland, data on abundance and prey capture success of plunge-divers were collected in four spatio-temporal quadrats of 100 m × 100 m and analysed with concurrent measurements of water quality parameters using GLM regression with Pearson's correlation ***: Mean prey capture success of Pied Kingfishers(34.7 e two species responded differently to water clarity. The± 13.1%) and Common Terns(35.3 abundance of Common Terns was± 11.0%) were similar but th significantly higher in less transparent/more turbid water while that of Pied Kingfishers showed no significant relationship with turbidity and transparency. In contrast, the prey capture success of Common Terns was neither related to transparency nor turbidity, as opposed to that of Pied Kingfishers which was significantly higher in more turbid/less transparent waters. Correlations between capture success and bird abundance, as well as capture attempts were insignificant, suggesting that increased fish abundance associated with cloudy water may not necessarily promote higher abundance and capture success of foraging birds. Thus, when foraging in less transparent water, capture success may depend more on predator avoidance by fish prey than lower prey detectability of foraging ***: within a gradient of 15–51 cm transparency studied, lower water clarity did not constrain prey capture success of Common Terns and Pied Kingfishers. Further studies on the foraging ecology of plunge-divers in coastal Ghana are however r

关键词： Coastal Ghana Common Tern Pied Kingfisher Prey capture success water turbidity and transparency

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

Fractional Bateman–Feshbach Tikochinsky Oscillator

引用

Communications in Theoretical Physics 2014年第2期61卷 221-225页

作者： Dumitru Baleanu Jihad h.Asad Ivo Petras Department of Chemical and Materials Engineering Faculty of Engineering King Abdulaziz University Department of Mathematics and Computer Science Faculty of Arts and Sciences Cankaya University Institute of Space Sciences Department of Physics College of Arts and Sciences Palestine Technical University BERG Faculty Technical University of Kosice

In the last few years the numerical methods for solving the fractional differential equations started to be applied intensively to real world phenomena. having these things in mind in this manuscript we focus on the fractional Lagrangian and harniltonian of the complex Bateman-Feshbach Tikochinsky oscillator. The numerical analysis of the corresponding fractionaJ Euler-Lagrange equations is given within the Griinwald-Letnikov approach, which is power series expansion of the generating function.

关键词： Riemann-Liouville derivatives Bateman-Feshbach Tikochinsky oscillator fractional hamiltonianequations Griinwald-Letnikov approach

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

Spin and Pseudospin Symmetries of Dirac Equation and the Yukawa Potential as the Tensor Interaction

引用

Communications in Theoretical Physics 2012年第12期58卷 807-814页

作者： h.hassanabadi E.Maghsoodi S.Zarrinkamar Physics Department Shahrood University of Technology Department of Basic Sciences Garmsar Branch Islamic Azad University

Considering of a tensor interaction in Dirac equation removes the degeneracy in spin and pseudospin doublets and consequently leads to results consistent with the experimental data. here, instead of the commonly used Coulomb or linear terms, we investigate a tensor interaction of Yukawa form. we obtain arbitrary state solutions of Dirac equation under vector, scalar and tensor Yukawa potentials via a physical approximation and the Nikiforov-Uvarov methodology. The solutions are discussed in detail.

关键词： Dirac equation spin symmetry pseudospin symmetry tensor interaction Yukawa potential

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

Impact of heat shock on heat shock proteins expression, biological and commercial traits of Bombyx mori

引用

Insect Science 2006年第4期13卷 243-250页

作者： VASUDhA B. ChAVADI APARNA h. SOSALEGOwDA MANJUNAThA h.B OREGOwDA Departments of Sericulture Dharwad 580003 Karnataka India Departments of Biochemisrty Karnatak University Dharwad 580 003 Karnataka India

we report the thermotolerance of new bivoltine silkworm, Bombyx mori strains NB4D2, KSO1, NP2, CSR2 and CSR4 and differential expression of heat shock proteins at different instars. Different instars of silkworm larva were subjected to heat shock at 35℃, 40℃ and 45℃ for 2 hours followed by 2 hours recovery. heat shock proteins were analyzed by SDS-PAGE. The impact of heat shock on commercial traits of cocoons was analyzed by following different strategies in terms of acquired thermotolerance over control. Comparatively NP2 exhibited better survivability than other strains. Resistance to heat shock was increased as larval development proceeds in the order of first instar 〉 second instar 〉 third instar 〉 fourth instar 〉 fifth instar in all silkworm strains. Expression of heat shock proteins varies in different instars. 90 kDa in the first, second and third instars, 84 kDa in the fourth instar and 84, 62, 60, 47 and 33 kDa heat shock proteins in fifth instar was observed in response to heat shock. Relative influence of heat shock on commercial traits that correspond to different stages was significant in all strains. In NB4D2, cocoon and shell weight significantly increased to 17.52% and 19.44% over control respectively. heat shock proteins as molecular markers for evaluation and evolution of thermotolerant silkworm strains for tropics was discussed.

关键词： biological and commercial traits Bombyx mori heat shock heat shockproteins molecular chaperones thermotolerance

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

Influence of potassium fertilization and foliar application of zinc and phosphorus on growth,yield components,yield and fiber properties of Egyptian cotton(Gossypium barbadense L.)

引用

Journal of Plant Ecology 2008年第4期1卷 259-270页

作者： Zakaria M.Sawan Mahmoud h.Mahmoud Amal h.El-Guibali Cotton Research Institute Agricultural Research CenterMinistry of Agriculture and Land Reclamation9 Gamaa StreetGiza 12619Egypt Soils Water and Environment Research InstituteAgricultural Research CenterMinistry of Agriculture and Land Reclamation9 Gamaa StreetGiza 12619Egypt

Aims Supplying optimal quantities of mineral nutrients to growing crop plants is one way to improve crop *** need to be used rationally in order to avoid a negative ecological impact and undesirable effects on the sustainability of agricultural production *** application of nutrients also affects the farmer’s *** order to calculate the amount of fertilizer to be applied to crops,it is necessary to develop recommendation programmers that adjust nutrient rates to crop *** Experiments in two successive seasons were conducted to investigate the effect of K fertilization and foliar application of Zn and P on yield and fiber properties of cotton *** ***(0.0 and 47.4 kg of K ha^(-1))was soil applied,while chelated zinc(0.0 and 57.6 g of Zn ha^(-1),applied twice at 70 and 85 days after sowing‘DAS’)and phosphorus(0.0,576,1152 and 1728 g of P ha^(-1),applied twice at 80 and 95 DAS)were applied to the *** findings Dry matter yield,total chlorophyll concentration,K,Zn and P uptake per plant,number of opened bolls per plant,boll weight,seed index,lint index,seed cotton yield per plant,seed cotton and lint yield ha^(-1) and earliness of harvest increased with the application of K,Zn and *** generally had no significant effect on lint percentage and fiber properties,with exceptions,for micronaire reading and flat bundle strength,and uniformity ratio,where the mean values of these characters were significantly increased over the untreated control by applying K,and for the micronaire reading in the first season,when applying P at 1728 g ha^(-1),and uniformity ratio in the second season,when applying Pat 1152 and 1728 g ha^(-1),where the mean values of these characters were significantly increased over the untreated control by applying *** the conditions of this study,applying K fertilization at 47.4 kg ha^(-1) combined with spraying cotton plants with zinc at 57.6 g ha^(-1) and also with P at

关键词： cotton fiber properties phosphorus potassium yield and yield components zinc

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

Simulation of multiple scattering of seismic waves by spatially distributed inclusions

引用

Science China(Technological Sciences) 2000年第4期43卷 387-394页

作者：刘恩儒 QUEEN John h 张中杰陈东 Institute of Geophysics Chinese Academy of SciencesBeijing 100101China British Geological Survey Edinburgh EH9 3LAUK Concoco Inc. HoustonUSA77079

A 2D elastodynamic boundary element method (BEM) is used to solve multiple scattering of elastic waves. The method is based on the integral representation of an elastic wave-field by assuming a fictitious source distribution on the scattering objects or inclusions, i.e. a mathematical description of huygens’ principle, and the fictitious source distribution can be found by matching appropriate boundary conditions at the boundary of the inclusions. Numerical studies show that in the presence of cracks, spatial and scale-length distributions are important and different spatial arrangements of the same scatters lead to profound differences in scattering characteristics, in particular the frequency contents of the transmitted wave-fields. The frequency characteristics, such as the frequency of peak attenuation , can be related to spatial size parameters of the model.

关键词： seismic waves multiple scattering inclusions BEM.

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

Meteorological impacts on evapotranspiration in different climatic zones of Pakistan

引用

Journal of Arid Land 2017年第6期9卷 938-952页

作者： Shahzada ADNAN Kalim ULLAh Azmat h KhAN GAO Shouting Department of Meteorology COMSATS Institute of Information Technology Islamabad 44000 Pakistan Pakistan Meteorological Department Islamabad 44000 Pakistan State key Laboratory of Cloud-Precipitation Physics and SevereStorms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Arid regions are highly vulnerable and sensitive to drought. The crops cultivated in arid zones are at high risk due to the high evapotranspiration and water demands. This study analyzed the changes in seasonal and annual evapotranspiration（ET） during 1951–2016 at 50 meteorological stations located in the extremely arid, arid, and semi-arid zones of Pakistan using the Penman Monteith（PM） method. The results show that ET is highly sensitive and positively correlated to temperature, solar radiation, and wind speed whereas vapor pressure is negatively correlated to ET. The study also identifies the relationship of ET with the meteorological parameters in different climatic zones of Pakistan. The significant trend analysis of precipitation and temperature（maximum and minimum） are conducted at 95% confidence level to determine the behaviors of these parameters in the extremely arid, arid, and semi-arid zones. The mean annual precipitation and annual mean maximum temperature significantly increased by 0.828 mm/a and 0.014℃/a in the arid and extremely arid zones, respectively. The annual mean minimum temperature increased by 0.017℃/a in the extremely arid zone and 0.019℃/a in the arid zone, whereas a significant decrease of 0.007℃/a was observed in the semi-arid zone. This study provides probabilistic future scenarios that would be helpful for policy-makers, agriculturists to plan effective irrigation measures towards the sustainable development in Pakistan.

关键词： evapotranspiration meteorological parameters climatic zone Penman Monteith method Pakistan

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

Oxytocin structure and function in New world monkeys:from pharmacology to behavior

引用

Integrative Zoology 2018年第6期13卷 634-654页

作者： Aaryn MUSTOE Jack h.TAYLOR Jeffrey A.FRENCh Program in Neuroscience and Behavior University of Nebraska at OmahaOmahaNebraskaUSA

Oxytocin(OT)is a hypothalamic nonapeptide that mediates a host of physiological and behavioral processes in-cluding reproductive physiology and social *** the OT sequence structure is highly conserved among mammals,New world monkeys(NwMs)represent an unusual“hot spot”in OT structure variability among *** least 6 distinct OT ligand variants among NwMs exist,yet it is currently unclear whether these evolved structural changes result in meaningful functional *** offer a new area to explore how these modifications to OT and its canonical G-protein coupled OT receptor(OTR)may mediate specific cellular,physiological and behavioral *** this review,we highlight relationships between OT ligand and OTR structural variability,specifically examining coevolution between OT ligands,OTRs,and physiological and behavioral phenotypes across *** consider whether these evolved modifications to the OT structure alter pharmacological profiles at human and marmoset OTRs,including changes to receptor binding,intracellular signaling and receptor ***,we evaluate whether exogenous manipulation using OT variants in marmoset monkeys differentially enhance or impair behavioral processes involved in social relationships between pairmates,opposite-sex strangers,and parents and their ***,it appears that changes to OT ligands in NwMs result in important changes ranging from cellular signaling to broad measures of social behavior.

关键词： cell signaling marmoset oxytocin receptor pharmacology social behavior

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

Multimedia model of atrazine in plant-soil-groundwater system with a fugacity approach

引用

Journal of Environmental Sciences 2001年第4期13卷 466-471页

作者： Ye, C.-m. Lei, Z.-f. wang, X.-j. Gong, A.-j. Zheng, h.-h. Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

The application of atrazine in China during the last ten years has led to some environmental problems. In this paper, the multimedia model of atrazine in soil-plant-groundwater system at Baiyangdian Lake area in Northern China was established using a fugacity approach, and verified with observed values. The model involved 7 environmental compartments which are air, groundwater, soil, corn roots, corn stem, corn leaf and kernel of corn. The results showed that the relative errors between calculated and observed values have a mean value of 24.7%, the highest value is 48% and the lowest value is 1.4%. All these values indicated that this multimedia model can be used to simulate the environmental fate of atrazine. Both the calculated and observed values of concentrations of atrazine in plant compartments are in the following order: in corn roots > in corn stem > in kernel of corn > in corn leaf, it exhibited a good regularity. The prediction results indicated that concentrations of atrazine in the groundwater and kernel of corn will override the limitation of 3 μg/L and 0.05 mg/kg respectively.

关键词： Concentration (process) Error detection Groundwater Lakes Plants (botany) Soils

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

Ground movements due to deep excavations in Shanghai： Design charts

引用

Frontiers of Structural and Civil Engineering 2014年第3期8卷 201-236页

作者： Malcolm D. BOLTON Sze-Yue LAM Paul J. VARDANEGA Charles w. w. NG Xianfeng MA Department of Engineering University of Cambridge Cambridge CB2 1PZ United Kingdom Advanced Geomechanics Perth Western Australia 6009 Australia Department of Civil Engineering University of Br&tol Bristol BS8 1TR United Kingdom Department of Civil and Environmental Engineering The Hong Kong University of Science and Technology Hong Kong China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tong/i University Shanghai 200092China

Recent research has clarified the sequence of ground deformation mechanisms that manifest themselves when excavations are made in soft ground. Furthermore, a new framework to describe the deformability of clays in the working stress range has been devised using a large database of previously published soil tests. This paper aims to capitalize on these advances, by analyzing an expanded database of ground movements associated with braced excavations in Shanghai. It is shown that conventional design charts fail to take account either of the characteristics of soil deformability or the relevant deformation mechanisms, and therefore introduce significant scatter. A new method of presentation is found which provides a set of design charts that clarify the influence of soil deformability, wall stiffness, and the geometry of the excavation in relation to the depth of soft ground.

关键词： Shanghai excavations mobilizable strength design dimensionless groups design charts

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

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

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：