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Time dependent integration of matrix metalloproteinases and their targeted substrates directs axonal sprouting and synaptogenesis following central nervous system injury

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Neural Regeneration Research 2014年第4期9卷 362-376页

作者： Linda L.Phillips Julie L.Chan Adele e.Doperalski Thomas M.Reeves Department of Anatomy and Neurobiology Virginia Commonwealth UniversityRichmondVAUSA

Over the past two decades, many investigators have reported how extracellular matrix molecules act to regulate neuroplasticity. The majority of these studies involve proteins which are targets of matrix metalloproteinases. Importantly, these enzyme/substrate interactions can regulate degenerative and regenerative phases of synaptic plasticity, directing axonal and dendritic reorganization after brain insult. The present review first summarizes literature support for the prominent role of matrix metalloproteinases during neuroregeneration, followed by a discussion of data contrasting adaptive and maladaptive neuroplasticity that reveals time-dependent metalloproteinase/substrate regulation of postinjury synaptic recovery. The potential for these enzymes to serve as therapeutic targets for enhanced neuroplasticity after brain injury is illustrated with experiments demonstrating that metalloproteinase inhibitors can alter adaptive and maladaptive outcome. Finally, the complexity of metalloproteinase role in reactive synaptogenesis is revealed in new studies showing how these enzymes interact with immune molecules to mediate cellular response in the local regenerative environment, and are regulated by novel binding partners in the brain extracellular matrix. Together, these different examples show the complexity with which metalloproteinases are integrated into the process of neuroregeneration, and point to a promising new angle for future studies exploring how to facilitate brain plasticity.

关键词： neuroregeneration reactive synaptogenesis matrix metalloproteinases brain injury adaptive and maladaptive neuroplasticity metalloproteinase inhibition osteopontin lipocalin 2

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Bacteria abundance and diversity of different life stages of Plutella xylostella （Lepidoptera： Plutellidae）, revealed by bacteria culture-dependent and PCR-DGGe methods

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Insect Science 2015年第3期22卷 375-385页

作者： Xiao-Li Lin Qin-Jian Pan Hong-Gang Tian Angela e. Douglas Tong-Xian Liu State Key Laboratory of Crop Stress Biology for the Arid Areas and Key Laboratory of Northwest Loess Plateau Crop Pest Management of Ministry of Agriculture Northwest A&F University Yangling Shaanxi China Department of entomology and Department of Molecular Biology & Genetics Cornell University Ithaca NY 14853 USA

Microbial abundance and diversity of different life stages （fourth instar larvae, pupae and adults） of the diamondback moth, Plutella xylostella L., collected from field and reared in laboratory, were investigated using bacteria culture-dependent method and PCR-DGGe analysis based on the sequence of bacteria 16S rRNA V3 region gene. A large quantity of bacteria was found in all life stages ofP. xylostella. Field population had higher quantity of bacteria than laboratory population, and larval gut had higher quantity than pupae and adults. Culturable bacteria differed in different life stages ofP. xylostella. Twenty-five different bacterial strains were identified in total, among them 20 strains were presented in larval gut, only 8 strains in pupae and 14 strains in adults were detected. Firmicutes bacteria, Bacillus sp., were the most dominant species in every life stage. 15 distinct bands were obtained from DGGe electrophoresis gel. The sequences blasted in GenBank database showed these bacteria belonged to six different genera. Phylogenetic analysis showed the sequences of the bacteria belonged to the Actinobacteri, Proteobacteria and Firmicutes. Serratia sp. in Proteobacteria was the most abundant species in larval gut. In pupae, unculturable bacteria were the most dominant species, and unculturable bacteria and Serratia sp. were the most dominant species in adults. Our study suggested that a combination of molecular and traditional culturing methods can be effectively used to analyze and to determine the diversity of gut microflora. These known bacteria may play important roles in development of P. xylostella.

关键词： diamondback moth gut flora insect bacteria microbial diversity 16S rRNA

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Overview of power electronics technology and applications in power generation, transmission and distribution

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Journal of Modern Power Systems and Clean energy 2017年第4期5卷 499-514页

作者： J.M.MAZA-ORTeGA e.ACHA S.GARCIA A.GóMeZ-eXPóSITO Department of electrical engineering University of SevillaSevilleSpain Department of electrical energy engineering Tampere University of TechnologyTampereFinland School of electrical engineering Universidad MichoacanaMoreliaMexico

The main objective of this paper is ***, to provide an overview of the current status of the power electronics technology, one of the key actors in the upcoming smart grid paradigm enabling maximum power throughputs and near-instantaneous control of voltages and currents in all links of the power system chain. Second, to provide a bridge between the power systems and the power electronic communities, in terms of their differing appreciation of how these devices perform when connected to the power grid. Third, to discuss on the role that the power electronics technology will play in supporting the aims and objectives of future decarbonized power systems. This paper merges the equipment, control techniques and methods used in flexible alternating current transmission systems(FACTS) and high voltage direct transmission(HVDC) equipment to enable a single, coherent approach to address a specific power system problem, using ‘best of breed’ solutions bearing in mind technical, economic and environmental issues.

关键词： Flexible alternating current transmission systems(FACTS) High voltage direct transmission(HVDC) Voltage source converter(VSC) Insulated gate bipolar transistor(IGBT) Smart grids

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Regional Soil Mapping Using Multi-Grade Representative Sampling and a Fuzzy Membership-Based Mapping Approach

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Pedosphere 2017年第2期27卷 344-357页

作者： YANG Lin A-Xing ZHU ZHAO Yuguo LI Decheng ZHANG Ganlin ZHANG Shujie Lawrence e. BAND State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) State Key Laboratory of Resources and environment Information System Institute of Geographical Sciences and Resources Research Chinese Academy of Sciences Beijing 100101 (China) Key Laboratory of Virtual Geographic environment (Nanjing Normal University) Ministry of Education Nanjing 210023 (China) Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application School of Geography Nanjing Normal University Nanjing 210023 (China) State Key Laboratory Cultivation Base of Geographical environment evolution (Jiangsu Province) Nanjing 210023 (China) Department of Geography University of Wisconsin-Madison Madison WI 53706 (USA) China Academy of Urban Planning & Design Beijing 100037 (China) Institute for the environment University of North Carolina Chapel Hill Chapel Hill NC 27599 (USA)

High-resolution and detailed regional soil spatial distribution information is increasingly needed for ecological modeling and land resource management. For areas with no point data, regional soil mapping includes two steps： soil sampling and soil mapping. Because sampling over a large area is costly, efficient sampling strategies are required. A multi-grade representative sampling strategy, which designs a small number of representative samples with different representative grades to depict soil spatial variations at different scales, could be a potentially efficient sampling strategy for regional soil mapping. Additionally, a suitable soil mapping approach is needed to map regional soil variations based on a small number of samples. In this study, the multi-grade representative sampling strategy was applied and a fuzzy membership-weighted soil mapping approach was developed to map soil sand percentage and soil organic carbon （SOC） at 0-20 and 20-40 cm depths in a study area of 5 900 km2 in Anhui Province of China. First, geographical sub-areas were delineated using a parent lithology data layer. Next, fuzzy c-means clustering was applied to two climate and four terrain variables in each stratum. The clustering results （environmental cluster chains） were used to locate representative samples. evaluations based on an independent validation sample set showed that the addition of samples with lower representativeness generally led to a decrease of root mean square error （RMSe）. The declining rates of RMSe with the addition of samples slowed down for 20-40 cm depth, but fluctuated for 0-20 cm depth. The predicted SOC maps based on the representative samples exhibited higher accuracy, especially for soil depth 20-40 cm, as compared to those based on legacy soil data. Multi-grade representative sampling could be an effective sampling strategy at a regional scale. This sampling strategy, combined with the fuzzy membership-based mapping approach, could be an optional effec

关键词： fuzzy clustering parent lithology representative grade samphng strategy soil spatial variations

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On the existence of Absolute Instability in Bluff Body Wakes

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Communications in Nonlinear Science and Numerical Simulation 1996年第3期1卷 4-8页

作者： Chuanping SHAO Xuequan e & Wei WANG (Laboratory of Applied Fluid Mechanics, Institute of Mechanics, Chinese Academy ofSciences, 15 Zhong Guan Cun Road, Beijing 100080, China)e-mail: shaocp@cc5 . Imech .ac. cn Laboratory of Applied Fluid Mechanics Institute of Mechanics Chinese Academy of Sciences 15 Zhong Guan Cun Road Beijing 100080 China

The wake stability of steady flow past a circular cylinder has been studiedexperimentally An impulse perturbation signal（very short in time, finite in amplitude） wasgiven to the wake from a small hole on the back of the cylinder, and its long time evolution inthe wake was detected by a hot film probe at a fixed point. The test Reynolds number rangeRe=30 ~ 320. The restult shows that （1）ahsolute instability exists in the wake when Re=55～320. （2） The absolute region extends from 0.5 eynlods number increases from 55 to 200.

关键词： absolute Instability wake circular cylinder

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Balanced and Unbalanced Components of Moist Atmospheric Flows with Phase Changes

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Chinese Annals of Mathematics,Series B 2019年第6期40卷 1005-1038页

作者： Alfredo N.WeTZeL Leslie M.SMITH Samuel N.STeCHMANN Jonathan e.MARTIN Department of Mathematics University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics and Department of engineering Physics University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics and Department of Atmospheric and Oceanic Sciences University of Wisconsin-MadisonMadisonWI 53706USA Department of Atmospheric and Oceanic Sciences University of Wisconsin-MadisonMadisonWI 53706USA

Atmospheric variables(temperature, velocity, etc.) are often decomposed into balanced and unbalanced components that represent low-frequency and high-frequency waves, respectively. Such decompositions can be defined, for instance, in terms of eigenmodes of a linear operator. Traditionally these decompositions ignore phase changes of water since phase changes create a piecewise-linear operator that differs in different phases(cloudy versus non-cloudy). Here we investigate the following question: How can a balanced–unbalanced decomposition be performed in the presence of phase changes? A method is described here motivated by the case of small Froude and Rossby numbers,in which case the asymptotic limit yields precipitating quasi-geostrophic equations with phase changes. Facilitated by its zero-frequency eigenvalue, the balanced component can be found by potential vorticity(PV) inversion, by solving an elliptic partial differential equation(PDe), which includes Heaviside discontinuities due to phase changes. The method is also compared with two simpler methods: one which neglects phase changes, and one which simply treats the raw pressure data as a streamfunction. Tests are shown for both synthetic, idealized data and data from Weather Research and Forecasting(WRF) model simulations. In comparisons, the phase-change method and no-phase-change method produce substantial differences within cloudy regions, of approximately 5K in potential temperature, due to the presence of clouds and phase changes in the data. A theoretical justification is also derived in the form of a elliptic PDe for the differences in the two streamfunctions.

关键词： Potential vorticity inversion Moist atmospheric dynamics Slow-fast systems Balanced-unbalanced decomposition elliptic partial differential equations

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Prognostication of hydrocarbon generative potential in the onshore and offshore Niger Delta, Nigeria using TOC content and rock-eval pyrolysis techniques

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Chinese Journal Of Geochemistry 2014年第2期33卷 138-144页

作者： Nyantakyi e.K. Li Tao Hu Wangshui Borkloe J.K. Nagre R.D. Civil engineering Department Kumasi Polytechnic School of earth Science Yangtze University Chemical engineering Department Kumasi Polytechnic College of Petroleum engineering Yangtze University

This article prognosticates the hydrocarbon generation potential of core samples from fields A, B, C and D in Niger delta, Nigeria. The objectives of this study are to characterize the quality of these core samples by organic geochemical analyses. A total of ten core samples collected from fields A, B, C and D in Niger delta were analyzed using total organic carbon(TOC) content analysis, rock-eval pyrolysis technique. The analytical results of the studied core samples reveal that they have generally high total organic carbon contents(TOC), suggesting that conditions in the Niger delta favour organic matter production and preservation. There is a variation in the kerogen types and this may be attributed to the relative stratigraphic positions of the core samples within the Niger delta. The rock-eval results indicate that the samples from fields C and D contain predominantly Type II kerogen with a capacity to generate oil and gas and hence have good generative potential. The samples from fields A and B contain mainly Type III kerogen and are gas-prone with moderate generative potential.

关键词：尼日尔三角洲热解技术尼日利亚生烃潜力 TOC 岩石潜力预测干酪根类型

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Preparation and characterization of the magnetic layered double hydroxide fluorescence composite

Preparation and characterization of the magnetic layered dou...

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第八届中国功能材料及其应用学术会议

作者： CAO Ju-qin DONG Li-e ZHANG Feng-yuan GOU Guo-jing Medical chemistry department School of Basic MedicalNingxia medical university

ISBN: (纸本)9783037859698

A fluorescence composite of magnetic layered double hydroxide(MLDH) and fluorescein(FLU)was synthesizedby ion change *** crystal structure and properties of the intercalated compoundMLDH-FLU were investigated through XRD,IR,TeM and TG-DSC *** show that fluorescein is suited for intercalation assembly with MLDH,producing MLDH-FLU composite which could be used as afluorescence probe to test the celltransmission efficiency of MLDH delivery system.

关键词： Magnetic layered double hydroxides Intercalation Supra-molecular assembly Fluorescence probe

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Changes in rainfall partitioning caused by the replacement of native dry forests of Lithraea molleoides by exotic plantations of Pinus elliottii in the dry Chaco mountain forests, central Argentina

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Journal of Arid Land 2020年第5期12卷 717-729页

作者： Samia S CORTÉS Juan I WHITWORTH-HULSe eduardo L PIOVANO Diego e GURVICH Patricio N MAGLIANO Land Science Research Center(CICTeRRA-CONICeT)and National University of Córdoba Av.Vélez Sarsfield 1611X5016GCA CórdobaArgentina Multidisciplinary Institute of Plant Biology National University of Córdoba and CONICETCC 495X5000JJC CórdobaArgentina environmental Study Group Institute of Applied Maths of San LuisNational University of San Luis and CONICETEjército de los Andes 950D5700HHW San LuisArgentina Department of Biology Faculty of ChemistryBiochemistry and PharmacyNational University of San LuisEjército de los Andes 950D5700HHW San LuisArgentina

The replacement of native dry forests by commercial(exotic)tree plantations could generate changes in rainfall partitioning,which further affects the water *** this study,we determined(i)the rainfall partitioning into interception,throughfall and stemflow,(ii)the role of rainfall event size on rainfall partitioning,(iii)the pH of water channelized as throughfall and stemflow,and(iv)the runoff in Lithraea molleoides(a native species)and Pinus elliottii(an exotic species)stands in the dry Chaco mountain forests,central *** average,interception,throughfall and stemflow accounted for 19.3%,79.5%and 1.2%of the gross rainfall in *** stand,and 32.6%,66.7%and 0.7%of the gross rainfall in *** stand,*** of interception,throughfall and stemflow presented positive linear relationships with the increment of rainfall event size for both tree species(Pes).Percentages of interception,throughfall and stemflow were all related to the increment of rainfall event size,showing different *** increasing rainfall event size,interception exponentially decreased,throughfall asymptotically increased and stemflow linearly *** *** and *** stands presented significant differences in the pH values of water channelized as throughfall(6.3 vs.6.7,respectively;Pemflow(4.5 vs.5.8,respectively;Ped only 0.3%of the gross rainfall in *** stand and was zero in *** *** results showed that the native species *** presented 13.6%more water reaching the topsoil(i.e.,net rainfall;net rainfall=gross rainfall-interception-runoff)than the exotic species *** study improves our understanding of the effects of native vegetation replacement on the local water balance in the dry forest ecosystems.

关键词： drylands ecohydrology land use changes spatial heterogeneity water-limited environments

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Nonlinear Dust Acoustic Waves in Dissipative Space Dusty Plasmas with Superthermal electrons and Nonextensive Ions

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Communications in Theoretical Physics 2016年第5期65卷 606-612页

作者： A.M.el-Hanbaly e.K.el-Shewy M.Sallah H.F.Darweesh Theoretical Physics Research Group Physics Department Faculty of Science Mansoura University Department of Physics Taibah University

The nonlinear characteristics of the dust acoustic(DA)waves are studied in a homogeneous,collisionless,unmagnetized,and dissipative dusty plasma composed of negatively charged dusty grains,superthermal electrons,and nonextensive *** pseudopotential technique has been employed to study the large amplitude DA ***(Sagdeev pseudopotential)has an evidence for the existence of compressive and rarefractive *** global features of the phase portrait are investigated to understand the possible types of solutions of the Sagdeev *** the other hand,the reductive perturbation technique has been used to study small amplitude DA waves and yields the Korteweg-de Vries-Burgers(Kd V-Burgers)equation that exhibits both soliton and shock *** behavior of the obtained results of both large and small amplitude is investigated graphically in terms of the plasma parameters like dust kinematic viscosity,superthermal and nonextensive parameters.

关键词： Sagdeev pseudopotential KdV-Burgers equation soliton and shock waves reductive perturbation dust kinematic viscosity

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