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Arctic spring: the arrival biology of migrant birds

动物学报 2004年第6期50卷 948-960页

作者： John C.WINGFIELD Noah OWEN-ASHLEY Z.Morgan BENOWITZ-FRED-ERICKS Sharon E.LYNN Thomas P.HAHN Haruka WADA Creagh BRE-UNER Simone L.MEDDLE L.Michael ROMERO Department of Zoology Box 351800.University of WashingtonScattleWashington 98195USA Department of Zoology Box 351800University of Wsshington.Scattle.Washington 98195USA Department of Biology College of WoosterWoasterOhio 44691USA Section of Neurobiology Physiology and BehaviorUniversity of CaliforniaDavisCalifornis 95616USA Integrative Biology Patterson LabsRm 141University of TexasAustinTexas 78712USA Laboratory of Neuroendocrinology School of Biomedical and Clinical Laborstory SciencesUnivereity of Edinburgh.Hugh Robson BuildingGeorge SquareEdinbungh EH89XD.UK Department of Biology Tuftus UniversityMedfordMassachusetts 02155.USA

On arrival in the Arctic, migrant birds must adjust their physiology and behavior to unpredictable snow cover, weather, food sources and predator pressure. In other words they must be resistant to environmental perturbations (stress) so that they can migrate to their tundra nesting areas and settle on territories as soon as possible. They can then begin breeding as soon as when environmental conditions become favorable. They do this partly by using micro-habitats such as areas where snow depth is low, and patches of tundra that melt out rapidly (especially near willows Salix sp). Ground temperatures increase dramatically within hours after exposure to sun; and invertebrate activity begins simultaneously. Wind speeds are attenuated almost completely within 10 cm of the ground in willows and tussock tundra. The combination of these conditions provides an ideal refuge, especially for passerine migrants in early spring. However, if conditions worsen, the birds can leave. There are adjustments of the adrenocortical responses to stress because arctic conditions in spring are potentially severe, at least compared with wintering grounds to the south. Secretion of corticosterone in response to acute stress is enhanced at arrival in males, accompanied by a decrease in sensitivity to negative feedback and a change in responsiveness of the adrenal cortex cells to adrenocorticotropin. There is also an increase in levels of corticosterone-binding globulin (CBG) so that the actions of corticosterone are buffered according to the severity of environmental conditions. Regulation at the level of genomic receptors, particularly the low affinity glucocorticosteroid-like receptor for corticosterone in brain and liver, may be important; and non-genomic actions of corticosterone may play a major role too. In other words, the hormone-behavior system associated with arrival biology is highly flexible.

关键词： Arctic Migration Stress Adrenal Corticosterone Receptor

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Synthesis and characterization of ZnO–CuO nanocomposites powder by modified perfume spray pyrolysis method and its antimicrobial investigation

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Journal of Semiconductors 2018年第3期39卷 1-7页

作者： D.Saravanakkumar S.Sivaranjani K.Kaviyarasu A.Ayeshamariam B.Ravikumar S.Pandiarajan C.Veeralakshmi M.Jayachandran M.Maaza Research and Development Center Bharathiyar UniversityCoimbatore641046India Department of Physics SBM College of Engineering&TechnologyDindigul624001India UNESCO-UNISA Africa Chair in Nanoscience's/Nanotechnology Laboratories College of Graduate StudiesUniversity of South Africa(UNISA)Muckleneuk RidgePretoriaSouth Africa Nanosciences African network(NANOAFNET) Materials Research Group(MRG)iThemba LABS-National Research Foundation(NRF)Somerset WestWestern Cape ProvinceSouth Africa Department of Physics Khadir Mohideen CollegeAdirampattinam614701India Department of Physics Devanga Arts CollegeAruppukkottai626101India Department of Physics Sethu Institute of TechnologyPullorKariapatti626115India

Pure ZnO, ZnO–CuO nanocomposites can be synthesized by using a modified perfume spray pyrolysis method（MSP）. The crystallite size of the nanoparticles（NPs） has been observed by X-ray diffraction pattern and is nearly 36 nm. Morphological studies have been analyzed by using Field Emission Scanning Electron Microscopy（FESEM） and its elemental analysis was reported by Elemental X-ray Analysis（EDX）; these studies confirmed that ZnO and CuO have hexagonal structure and monoclinic structure respectively. Fourier Transform Infrared（FTIR） spectra revealed that the presence of functional frequencies of ZnO and CuO were observed at 443 and 616 *** average bandgap value at 3.25 e V using UV–vis spectra for the entitled composite has described a blue shift that has been observed here. The antibacterial study against both gram positive and negative bacteria has been studied by the disc diffusion method. To the best of our knowledge, it is the first report on ZnO–CuO nanocomposite synthesized by a modified perfume spray pyrolysis method.

关键词： MSP method XRD FTIR FESEM CuO nanoparticles

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基于插值和加窗傅里叶变换的曲率模态提取算法

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重庆理工大学学报（自然科学） 2013年第9期27卷 35-37,52页

作者：杨翀 FU Yu 朱长春田光明中国工程物理研究院总体工程研究所四川绵阳621900 Temasek labs and School of MAE Nanyang Technological University

在通过测量振动参数的变化来检测结构裂纹的方法中,曲率模态法是较为有效的一种。曲率模态通常由中心差分法求取位移模态的2阶导数来获得,但由于模态的测量比较困难,分辨率和精度较低,所以差分法计算误差较大。针对该情况,引入插值和加... 详细信息

在通过测量振动参数的变化来检测结构裂纹的方法中,曲率模态法是较为有效的一种。曲率模态通常由中心差分法求取位移模态的2阶导数来获得,但由于模态的测量比较困难,分辨率和精度较低,所以差分法计算误差较大。针对该情况,引入插值和加窗傅里叶变换算法来计算曲率模态,并通过带裂纹悬臂梁的测量实验进行验证。同中心差分法进行对比可知:提出的算法能大幅提升计算的精度,准确地判断裂纹的所在位置。

关键词：加窗傅里叶变换裂纹检测曲率模态

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A decade of development in advanced dielectrics research from JAD’s perspectives

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Journal of Advanced Dielectrics 2020年第4期10卷 1-5页

作者： Alexei A.Bokov Zuo-Guang Ye Xi Yao Xiaoyong Wei Nan Zhang Jihui Gong Department of Chemistry and 4D labs Simon Fraser University Burnaby British ColumbiaV5A 1S6Canada Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric Research School of Electronic Science and Engineering Xi’an Jiaotong University 710049 Xi’anP.R.China

Dielectrics form an important class of functional materials with unique electric and electronic properties,which are widespread in advanced technologies,but,surprisingly,at the time of the creation of Journal of Advanced Dielectrics(JAD)there was no journal specially dedicated to the study of these *** was intended to fill the *** was conceived as a forum for the interdisciplinary community of physicists,chemists,material scientists and electrical engineers working with dielectrics and related materials and *** journal is published by the largest international scientific publisher in the Asia-Pacific region,World Scientific,and sponsored by the International Centre for Dielectric Research(ICDR)at Xi’an Jiaotong University(XJTU),China.

关键词： materials. journal dielectrics

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广西电网在线动态安全性分析系统

广西电网在线动态安全性分析系统

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广西电机工程学会第八届青年学术年会

作者：林曦高文建何朝阳薛峰许剑冰徐泰山薛禹胜汪磊广西电力调度通信中心南瑞集团公司稳定技术分公司 PowerTech labs Inc．

广西电网在线动态安全性分析系统是国内第一套基于详细模型的暂态安全、电压安全在线分析系统。本文介绍了该系统的功能,结构和试运行情况等。并结合该系统实际情况讨论了一些开发在线动态安全性分析系统需要面对的特殊问题。

关键词：在线分析暂态安全电压安全预想事故集紧急控制措施集

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Characterization of physiological and molecular processes associated with potato response to Zebra chip disease

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Horticulture Research 2017年第1期4卷 53-61页

作者： Chika C Nwugo Venkatesan G Sengoda Li Tian Hong Lin San Joaquin Valley Agricultural Sciences Center USDA-ARSParlier93658CAUSA California Seed and Plant labs Sacramento95668CAUSA USDA-ARS Yakima Agricultural Research LaboratoryWapato98951WAUSA Department of Plant Sciences University of CaliforniaDavisDavis95616CAUSA

Transcriptional analyses identified molecular mechanisms associated with the response of leaf and root potato tissues to‘*** solanacearum’(Lso)infection,presumptive causal agent of zebra chip disease(ZC).Putative Lso infection affected several host processes including defense response-,regulation-,starch metabolism-and energy production-related ***,while proteinase inhibitors were strongly upregulated in leaf tissues,a concomitant downregulation was observed in root *** polymerase chain reaction(qPCR)analysis suggests that alternative splicing might play a ***,the transcriptional expression of redox homeostasis-related genes,including superoxide dismutase,showed the most inconsistent response to Lso in leaf and root tissues,highlighting potential targets of Lso ***,a net increase in gene expression in ZC-affected tissues despite the concomitant downregulation of photosynthesis-related processes,suggests a putative Lso-mediated low *** nutritional analyses revealed a hypothesized Lso-mediated increase in nutrient accumulation,particularly a 210 and 108%increases in the potassium concentration of ZC-affected leaf and root tissues,respectively,suggesting an important role for potassium in ZC *** study highlights insights of above and below ground tissues in molecular and physiological aspects associated with potato response to ZC.

关键词： metabolism homeostasis potassium

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利用分布有/无数据预测物种空间分布的研究方法综述!

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生态学报 2013年第22期33卷 7047-7057页

作者：刘芳李晟李迪强中国林业科学研究院森林生态环境与保护研究所国家林业局森林生态环境重点实验室北京100091 Department of Forest&Wildlife Ecology University of Wisconsin-Madison209 Russell Labs1630 Linden Drive University of Wisconsin-Madison Madison

详细的物种地理分布信息是生态学研究和制定保护策略的基础。相比较于直接估测种群数量,获取物种分布的有/无数据更为实用。因此,利用分布有/无数据并结合环境变量建立模型预测物种空间分布的方法在近年来得到了长足发展,并被广泛应用... 详细信息

详细的物种地理分布信息是生态学研究和制定保护策略的基础。相比较于直接估测种群数量,获取物种分布的有/无数据更为实用。因此,利用分布有/无数据并结合环境变量建立模型预测物种空间分布的方法在近年来得到了长足发展,并被广泛应用。利用分布有/无数据预测物种分布,关键的步骤包括:1)构建总体概念模型,2)收集物种分布有/无数据,并准备环境变量图层;3)选择合适的统计模型和算法,以及4)对模型进行评估。概念模型提出研究假设,并确定数据收集及模型方法。收集物种分布数据有系统调查及非系统调查方法。筛选并准备与物种分布相关的环境变量,利用GIS工具处理,使之成为符合模型条件的具有合适的空间尺度的数字化图层。利用环境变量和物种分布有/无的数据,选择合适的方法及软件建立模型,并对模型进行检验和评估。总结了用于构建物种分布模型的不同算法和软件。针对以上各个环节,阐述利用物种分布有/无数据进行研究所需要的技术细节,以期望为读者提供借鉴。

关键词：有无数据物种分布模型取样模型评估

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Design of Digital Linear Power Supply with Low Current Ripple

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Journal of Mechanics Engineering and Automation 2023年第2期13卷 32-39页

作者： Che-Min Kung Yeh-Chen Yeh Wen-Tien Tsai Department of Green Energy and Environment Research labs Industrial Technology Research InstituteHsinchu County 310401Taiwan

A linear power supply is a circuit architecture directly driven by AC. Multiple high-voltage LEDs (light-emitting diodes) are connected in series to withstand the input voltage. The LEDs are divided into multiple segments through a segment switching mechanism to adapt to the pulsating DC changes after bridge rectification. Due to imperfect switching between control signals, there may be signal overlap or misalignment, which reduces circuit performance and component lifespan. Firstly, signal overlap occurs when the next segment opens before the previous segment is about to close. This state causes overlapping intervals where two segments of current combine, resulting in a high combined current that can lead to significant power losses and generate heat, potentially reducing the lifespan of the components. Secondly, signal misalignment occurs when the next segment prepares to open after the previous segment has completely closed. In this state, there is a time gap with no current flow, resulting in reduced output power and exacerbating LED flickering. Both of these undesirable phenomena introduce ripple into the LED output current. In this paper, a digitalized design is proposed to precisely compensate for the timing between alternating signals, significantly reducing output current ripple. This approach helps enhance power supply performance, extend component lifespan, and reduce LED index flicker.

关键词： LED linear flicker direct AC current ripple

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Influence of Different Sterilization Conditions on the Growth and Exopolysaccharide of Streptococcus thermophilusand Co-Cultivation with Lactobacillus delbrueckiisubsp. bulgaricusOLL1073R-1

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Advances in Microbiology 2015年第11期5卷 760-767页

作者： Junko Nishimura Seiya Makino Katsunori Kimura Emiko Isogai Tadao Saito Laboratory of Nutrition and Life Sciences Department of Biotechnology and Environmental Engineering Faculty of Engineering Hachinohe Institute of Technology Hachinohe Japan Laboratory of Animal Products Chemistry Graduate School of Agricultural Science Tohoku University Sendai Japan Food Science Research labs. Meiji Co. Ltd. Odawara Japan Laboratory of Animal Microbiology Graduate School of Agricultural Science Tohoku University Sendai Japan

The sterilization conditions between experiment and dairy industrial level are different and concern about influence on product’s qualities. In this study, the fermentation properties of Streptococcus thermophilus, alone and in combination with Lactobacillus delbrueckii subsp. bulgaricus, were evaluated in skim milk that had been subjected to distinct sterilization conditions. Growth, organic acid generation, and EPS production were determined using pasteurized or autoclaved milk. When S. thermophilus was cultivated in pasteurized skim milk, the growth was strain-dependent. On the other hand, growth of S. thermophilus was accelerated in autoclaved milk. Exocellular polysaccharide (EPS) production by L. bulgaricus was not affected by the combination of S. thermophilus strains. Thus, we observed that yogurt fermented by L. bulgaricus was minimally affected by the combination of S. thermophilus strains;growth of L. bulgaricus was maintained under the constant environment. These results should facilitate the development of fermented milk produced from L. bulgaricus in the dairy industry.

关键词： Streptococcus thermophilus Lactobacillus delbrueckii subsp. bulgaricus Sterilization Formic Acid Exopolysaccharide

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使用蓝牙5增强信标

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电子产品世界 2020年第4期27卷 37-40,61页

作者： Joe Tillison Silicon labs公司

讨论了蓝牙5中添加的广告扩展(advertising extension)和其他重要功能,这些功能可用于构建具有扩展功能的第二代信标,从而支持更多功能丰富的接近感知(proximity-aware)应用。

关键词：信标蓝牙5 广告扩展接近感知

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