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Effect of Intensive Inorganic fertilizer Application on Microbial Properties in a Paddy Soil of Subtropical China

Agricultural Sciences in China 2011年第11期10卷 1758-1764页

作者： Klemens Ekschmitt Stephanie I j Holzhauer Sabine Rauch justus Liebig University IFZ-Department of Animal EcologyH.-Buff-Ring 26-32D-35392 GiessenGermany

A field experiment with rice-rice rotation was conducted since 2002 in southeast China for investigating the response of soil microbial properties to intensive nitrogen fertilizer application. The tested soil was a subtropical paddy soil derived from Quaternary red clay. Differences between treatments existed in different application rates of urea when the experiment was designed. Urea was applied in five rates, i.e., 0, 0.5, 1, 1.5, and 2 U, equivalent to 0, 0.5, 1, 1.5, and 2 times the local average amount of urea application （900 kg urea ha-~ yr-~, equivalent to 414 kg N ha-1 yr-~）. In 2007, soil total nitrogen, available nitrogen, and soil organic carbon contents were increased by 10.2-27.9, 8.0-16.0, and 10.2-30.6%, respectively, in treatments with urea application rates of 0.5 to 2 U compared to control （0 U）. Microbial biomass carbon and nitrogen were also increased by 3.1-30.8 and 1.3-13.9%, respectively, in treatments with urea application. Basal respiration in treatments with urea input were 9.4-29.1% higher than that in control. However, changes of bacterial functional diversity had different trends. Urea fertilization enhanced bacterial functional diversity until treatment of 1 U, but re-decreased it from treatment of 1.5 U. Principal components analysis indicated that there were intimate relationships among soil organic matter, nitrogen nutrient, microbial biomass, and respiration. Nevertheless, microbial diversity was related to soil moisture contents after urea application. We conclude here that the application of N fertilizer improved soil microbial biomass and respiratory activity. But, microbial diversity was reduced when excessive urea was applied in the tested paddy soil.

关键词： paddy soil intensive N application microbial properties microbial functional diversity red soil region

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Molecular mechanisms underlying phosphate sensing, signaling, and adaptation in plants

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journal of Integrative Plant Biology 2014年第3期56卷 192-220页

作者： Zhaoliang Zhang Hong Liao William j.Lucas Department of Plant Biology College of Biological Sciences University of California State Key Laboratory for Conservation and Utilization of Subtropical Agro‐Bioresources Root Biology Center South China Agricultural University

As an essential plant macronutrient, the low availability of phosphorus （P） in most soils imposes serious limitation on crop production. Plants have evolved complex responsive and adaptive mechanisms for acquisition, remobilization and recycling of phosphate （Pi） to maintain P homeostasis. Spatio-temporal molecular, physiological, and biochemical Pi deficiency responses developed by plants are the consequence of local and systemic sensing and signaling pathways. Pi deficiency is sensed locally by the root system where hormones serve as important signaling components in terms of developmental reprogramming, leading to changes in root system architecture. Root-to-shoot and shoot-to-root signals, delivered through the xylem and phloem, respectively, involving Pi itself, hormones, miRNAs, mRNAs, and sucrose, serve to coordinate Pi deficiency responses at the whole-plant level. A combination of chromatin remodeling, transcriptional and posttranslational events contribute to globally regulating a wide range of Pi deficiency responses. In this review, recent advances are evaluated in terms of progress toward developing a comprehen- sive understanding of the molecular events underlying control over P homeostasis. Application of this knowledge, in terms of developing crop plants having enhanced attributes for P use efficiency, is discussed from the perspective of agricultural sustainability in the face of diminishing global P supplies.

关键词： Adaptation crop engineering strategies hormone networks local and long-distance sensing phosphate P use efficiency stress responses systemic signaling transcriptional regulation transport systems

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Vocal repertoire of the New Zealand kea parrot Nestor notabilis

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Current Zoology 2012年第5期58卷 727-740页

作者： Raoul SCHWING Stuart PARSONS Ximena j. NELSON School of Biological Sciences University of Auckland Private Bag 92019 Auckland New Zealand School of Biological Sciences University of Canterbury Private Bag 4800 Christchurch New Zealand

The unique alpine-living kea parrot Nestor notabilis has been the focus of numerous cognitive studies, but its com- munication system has so far been largely neglected. We examined 2,884 calls recorded in New Zealand＇s Southern Alps. Based on audio and visual spectrographic differences, these calls were categorised into seven distinct call types： the non-oscillating ＇screech＇ contact call and ＇mew＇; and the oscillating ＇trill＇, ＇chatter＇, ＇warble＇ and ＇whistle＇; and a hybrid ＇screech-trill＇. Most of these calls contained aspects that were individually unique, in addition to potentially encoding for an individual＇s sex and age. Additionally, for each recording, the sender＇s previous and next calls were noted, as well as any response given by conspecifics. We found that the previous and next calls made by the sender were most often of the same type, and that the next most likely pre- ceding and/or following call type was the screech call, a contact call which sounds like the ＇kee-ah＇ from which the bird＇s name derives. As a social bird capable of covering large distances over visually obstructive terrain, long distance contact calls may be of considerable importance for social cohesion. Contact calls allow kea to locate conspecifics and congregate in temporary groups for social activities. The most likely response to any given call was a screech, usually followed by the same type of call as the ini- tial call made by the sender, although responses differed depending on the age of the caller. The exception was the warble, the kea＇s play call, to which the most likely response was another warble. Being the most common call type, as well as the default response to another call, it appears that the ＇contagious＇ screech contact call plays a central role in kea vocal communication and social cohesion [Current Zoology 58 （5）： 727-740, 2012].

关键词： Acoustic signals Communication Kea Psittacidae Social behaviour Habitat

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基于1962至2022年极移观测值的时序分析及长期预报研究

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测绘地理信息 2024年第1期49卷 29-35页

作者：魏二虎李岩林白小宇王广渠刘经南武汉大学测绘学院湖北武汉430079 武汉大学卫星导航定位技术研究中心湖北武汉430079

极移参数(polar motion,PM)是地球定向参数(earth orientation parameter,EOP)的重要组成部分,在天文大地测量、卫星的导航定位以及卫星的自主定轨等领域有重要的应用。本文首先利用国际地球自转服务(international earth rotation and ... 详细信息

极移参数(polar motion,PM)是地球定向参数(earth orientation parameter,EOP)的重要组成部分,在天文大地测量、卫星的导航定位以及卫星的自主定轨等领域有重要的应用。本文首先利用国际地球自转服务(international earth rotation and reference systems service,IERS)提供的极移观测值进行极移时间序列频谱分析及周期项的提取。结果表明,快速傅里叶变换与离散傅里叶变换周期项提取到的周期项基本无差异,但极移X、Y分量时变分析结果存在差异。此外,本文将正弦逼近应用到极移参数的预报,对于长时间尺度的极移参数预报最小二乘外推模型效果最佳,但预报模型精度易受到周期项提取结果的影响;最小二乘外推模型在极移正向预报和反推拟合效果相近,借助正弦逼近方法可以一定程度上增强模型拟合效果。上述研究结果可为地球自转参数的预报研究提供参考。

关键词：极移时变性周期项物理成因长期预报

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Effect of seismic retrofit of bridges on transportation networks

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 169-179页

作者： Masanobu Shinozuka Yuko Murachi Michal j.Orlikowski Department of Civil and Environmental Engineering University of CaliforniaIrvineUSA Distinguished Professor and Chair Department of Civil and Environmental Engineering University of CaliforniaIrvineUSA Research Associate Department of Civil and Environmental Engineering Princeton UniversityUSA Undergraduate Student.

The objective of this research is to determine the effect earthquakes have on the performance of transportation network *** do this,bridge fragility curves,expressed as a function of peak ground acceleration(PGA)and peak ground velocity(PGV),were *** damage was evaluated under the 1994 Northridge earthquake and scenario earthquakes.A probabilistic model was developed to determine the effect of repair of bridge damage on the improvement of the network performance as days passed after the *** an example,the system performance degradation measured in terms of an index,'Drivers Delay,'is calculated for the Los Angeles area transportation system,and losses due to Drivers Delay with and without retrofit were estimated.

关键词： fragility curves seismic retrofit probabilistic model bridges transportation networks drivers delay performance index Northridge earthquake.

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functional brain imaging of gastrointestinal sensation in health and disease

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World journal of Gastroenterology 2007年第25期13卷 3438-3445页

作者： Lukas Van Oudenhove Steven j Coen Qasim Aziz Department of Neurosciences Division of Psychiatry & Department of Pathophysiology Gastroenterology Section University Hospital Gasthuisberg University of Leuven Belgium Centre for Neuroimaging Sciences Institute of Psychiatry London United Kingdom Division of Neuroscience & Medicine Department of GI Sciences Hope Hospital University of Manchester United Kingdom

It has since long been known, from everyday experience as well as from animal and human studies, that psychological processes-both affective and cognitive- exert an influence on gastrointestinal sensorimotor function. More specifically, a link between psychological factors and visceral hypersensitivity has been suggested, mainly based on research in functional gastrointestinal disorder patients. However, until recently, the exact nature of this putative relationship remained unclear, mainly due to a lack of non-invasive methods to study the （neurobiological） mechanisms underlying this relationship in non-sleeping humans. As functional brain imaging, introduced in visceral sensory neuroscience some 10 years ago, does provide a method for in vivo study of brain-gut interactions, insight into the neurobiological mechanisms underlying visceral sensation in general and the influence of psychological factors more particularly, has rapidly grown. In this article, an overview of brain imaging evidence on gastrointestinal sensation will be given, with special emphasis on the brain mechanisms underlying the interaction between affective ＆ cognitive processes and visceral sensation. first, the reciprocal neural pathways between the brain and the gut （brain- gut axis） will be briefly outlined, including brain imaging evidence in healthy volunteers. Second, functional brain imaging studies assessing the influence of psychological factors on brain processing of visceral sensation in healthy humans will be discussed in more detail. finally, brain imaging work investigating differences in brain responses to visceral distension between healthy volunteers and functional gastrointestinal disorder patients will be highlighted.

关键词： functional brain imaging functionalgastro-intestinal disorders Visceral hypersensitivity Gastrointestinal sensation Psychological factors

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The Product of the Restrained Domination Numbers of a Graph and Its Complement

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Acta Mathematica Sinica,English Series 2014年第3期30卷 445-452页

作者： johannes H.HATTINGH Ernst j.jOUBERT Department of Mathematics East Carolina University Department of Mathematics University of Johannesburg

Let G=（V,E） be a graph.A set S■V is a restrained dominating set if every vertex in V-S is adjacent to a vertex in S and to a vertex in *** restrained domination number of G,denoted γr（G）,is the smallest cardinality of a restrained dominating set of *** this paper,we show that if G is a graph of order n≥4,then γr（G）γr（G）≤*** also characterize the graphs achieving the upper bound.

关键词： Graph domination restrained domination Nordhaus-Gaddum upper bound

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Uniform Query framework for Relational and NoSQL Databases

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Computer Modeling in Engineering & Sciences 2017年第2期113卷 171-181页

作者： j.B.Karanjekar M.B.Chandak Shri Ramdeobaba College of Engineering and Management NagpurIndia and Izel Technologies Pvt Ltd.PuneIndia Shri Ramdeobaba College of Engineering and Management NagpurIndia

As the data managed by applications has evolved over the years with the arrival of Web 2.0,a large number of new databases have been developed to manage various types of *** the traditional relational databases continue to exist,NoSQL databases which are document oriented or key-value stores or columnar continue to evolve and are embraced very rapidly across the *** is not just the type of data handled by these databases that is different but also the query language they use is also *** paper talks about a uniform query framework that can be used for traditional relational databases and NoSQL *** query framework can also perform joins,aggregates,filter on data from various data sources in a single query.

关键词： NoSQL RDBMS data tetrieval inter-database joins SQL Cassandra MongoDB Calcite MySQL

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Humus horizon development during natural forest succession process in the Polish Carpathians

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journal of Mountain Science 2022年第3期19卷 647-661页

作者： justyna SOKOŁOWSKA Agnieszka jÓZEfOWSKA Tomasz ZALESKI Department of Soil Science and Agrophysics University of Agriculture in Krakowal.Mickiewicza 2131-120 KrakówPoland

As a result of socio-economic changes and land abandonment,the main ecological driver of the Carpathian landscape is the progression of the natural forest succession ***,aspects of this process have become worthy of attention,especially in the context of carbon sequestration and the management of protected *** processes,especially within the topsoil,are some of the most susceptible to change,due to the accumulation of organic matter during such land-use *** purposes of this study were to investigate the differences in topsoil development using the A Horizon Development Index(ADI)and to study the composition of humic substances and advanced organic matter humification in different land-use areas in selected Carpathian national parks,***,Magura and Pieniny National Parks in southern ***,a goal of this study was to compare the ADI and the spectroscopic coefficients of humic substances as indicators of the degree of humus horizon shaping as well as advanced organic matter *** total,ten transects were selected,each consisting of three different land-use areas:semi-natural meadow,successional forest and old-growth *** colour was determined in fresh and air-dried samples using the Munsell colour *** air-dried soil samples p H,soil texture,total organic carbon and total nitrogen were *** substances were extracted and further characterized by UV-VIS *** ADI confirmed the influence of natural forest succession on soil colour darkening and the development of the uppermost soil *** analyses of humic substances showed two different patterns depending on soil *** the 0–10 cm layer,natural forest succession reduced the rate of the humification process and decreased the degree of maturity of fulvic acids;in the 10–20 cm layer,it led to an increase in the rate of the humification process and a decrease in the content of humic and fulvic acids at the beginn

关键词： Land use changes Natural forest succession Polish Carpathians Landscape transformation Protected areas management Humic substances

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Statistical Behaviors of Quantum Spectra in Superheavy Nuclei

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Communications in Theoretical Physics 2003年第5期39卷 597-602页

作者： WUXi-Zhen LiZhu-Xia WANGNing j.a.Maruhn ChinaInstituteofAtomicEnergy P.O.Box275(18)Beijing102413China CenteroftheoreticalnuclearPhysics NationalLaboratoryofLanzhouHeavyIonAcceleratorLanzhou730000China ChinaInstituteofAtomicEnergy P.O.Box275(18)Beijing102413China InstituteofTheoreticalPhysics AcademiaSinicaP.O.Box2735Beijing100080China CenteroftheoreticalnuclearPhysics NationalLaboratoryofLanzhouHeavyIonAccele ChinaInstituteofAtomicEnergy P.O.Box275(18)Beijing102413China InstitutfuerTheoretischePhysikderjohannWolfgangGoethe-Universitat FrakfurtamMainGermany

from the point of view of the interplay between order and chaos, the most regular single-particle motion of neutrons has been found in the superheavy system with and based on the Skyrme–Hartree–fock model and in the system with and based on the relativistic mean-field model. It has been shown that the statistical analysis of spectra can give valuable information about the stability of suprheavy systems. In addition it may yield deep insight into the single-particle motion in the mean field formed by the superheavy system.

关键词： statistical properties of quantum spectra Poisson distribution superheavy systems

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