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Effects of endophyte infection on the competitive ability of Achnatherum sibiricum depend on endophyte species and nitrogen availability

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Journal of Plant Ecology 2019年第5期12卷 815-824页

作者： Yong Zhou Xia Li Hui Liu Yubao Gao Wade J.Mace Stuart d.Card Anzhi Ren department of Plant Biology and Ecology College of Life SciencesNankai University94 Weijin RoadTianjin 300071China College of Landscape and Travel Hebei Agricultural UniversityBaoding 071001China department of Plant Biology College of Life SciencesHebei UniversityBaoding 071001China AgResearch Ltd Grasslands Research CentrePrivate Bag 11008Palmerston North 4442New Zealand

Aims the leaves of almost all terrestrial plant species are colonized by endophytic *** to agronomic grasses,which usually harbor few endophytes,native grasses generally possess greater endophyte species *** studies examining endophyte effects on natural grasses under competition normally considered the infection status(infected or uninfected),and rarely considered endophyte *** We examined the effects of endophyte infection and of endophyte species on the interspecific competitive ability of a subdominant species,Achnatherum sibiricum,at two nitrogen levels(high ni-trogen and low nitrogen).Achnatherum sibiricum plants infected by two different species of endophyte(Epichloësibirica and ***)and uninfected plants were grown in monoculture and binary mixtures with a dominant species,Stipa grandis(six individuals per species for monocultures and three+three in-dividuals of each species in mixtures).Shoot and.root biomass,tiller number and total phenolic concentration were measured after 3 ***,the aggressivity index was calculated to compare the competitive ability of *** relative to *** Findings Both ***(Eg)-and ***(Es)-infected *** plants showed a greater competitive ability than the uninfected plants under high nitrogen supply,while the opposite result oc-curred under low nitrogen *** high nitrogen levels,Eg plants had a higher tiller number and a greater shoot biomass in-hibitory effect on *** than Es plants had when growing in mixture,while Es plants showed better root growth performance than Eg and uninfected plants under mixture conditions at all ni-trogen levels.A higher concentration of phenolic compounds in Eg plants than in Es plants might contribute to the higher inhibi-tory effect of Eg plants on competing *** study indicates that the interaction between endophyte infection and nitrogen availability can alter the competitive ability o

关键词： Achnatherum sibiricum Epichloëendophytes interspecific competition native grass nutrient supply

A Transcriptome Atlas of Physcomitrella patens Provides Insights into the Evolution and development of Land Plants

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Molecular Plant 2016年第2期9卷 205-220页

作者： Carlos Ortiz-Ramirez Marcela Hernandez-Coronado Anna Thamm Bruno Catarino Mingyi Wang Liam dolan Jose A.Feijo Jorg d. Becker Instituto Gulbenklan de Ciencia Rua da Quinta Grande 6 2780-156 Oeiras Portugal department of Plant Sciences University of Oxford South Parks Road Oxford OX1 3RB UK division of Plant Biology The Samuel Roberts Noble Foundation Ardmore OK 73401 USA department of Cell Biology and Molecular Genetics University of Maryland 0118 BioSclence Research Building College Park MD 20742-5815 USA These authors contributed equally to this article

Identifying the genetic mechanisms that underpin the evolution of new organ and tissue systems is an aim of evolutionary developmental biology. Comparative functional genetic studies between angiosperms and bryophytes can define those genetic changes that were responsible for developmental innovations. Here, we report the generation of a transcriptome atlas covering most phases in the life cycle of the model bryo- phyte Physcomitrella patens, including detailed sporophyte developmental progression. We identified a comprehensive set of sporophyte-specific transcription factors, and found that many of these genes have homologs in angiosperms that function in developmental processes such as flowering and shoot branching. deletion of the PpTCP5 transcription factor results in development of supernumerary sporangia attached to a single seta, suggesting that it negatively regulates branching in the moss sporophyte. Given that TCP genes repress branching in angiosperms, we suggest that this activity is ancient. Finally, compar- ison of P. patens and Arabidopsis thaliana transcriptomes led us to the identification of a conserved core of transcription factors expressed in tip-growing cells. We identified modifications in the expression patterns of these genes that could account for developmental differences between P. patens tip-growing cells and A. thaliana pollen tubes and.root hairs.

关键词： land plant evolution Physcomitrella patens transcriptome atlas TCP branching tip growth

Nutritional evaluation of integral cassava root silages for growing pigs

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Animal Nutrition 2016年第3期2卷 149-153页

作者： diego d.Araújo Alessandro B.Amorim Mayra A.d.Saleh Felipe Curcelli Pedro L.Perdigón Silvio J.Bicudo dirlei A.Berto department of Animal Production Faculty of Animal Science and Veterinary Medicine UNESP-So Paulo State University Institute of Agricultural Sciences and Technologies Federal University of Mato Grosso department of Crop Science Faculty of Agricultural Sciences UNESP-So Paulo State University Instituto de Ciencia Animal (ICA)

The experiment aimed at determining the nutritional value of integral cassava root silages with yogurt as inoculant or wastewater(manipueira) by liquid addition ensiling process. Eighteen crossbred piglets(Large White x Landrace), castrated males with an initial average weight of 50 kg were allocated in metabolism cages throughout 11-day trial duration(6 days for animal's adaptation to the cages and to the experimental diets, and 5 days of urine and faeces collection). The experimental design was a randomized block arrangement with 3 treatments and 6 replicates: basal diet(100%); mixture composed of75% basal diet and 25% integral cassava root silage with yogurt as inoculant; a mixture composed of 75%of basal diet and 25% integral cassava root silage with wastewater. The silages with wastewater and yogurt presented the following values of apparent digestibility of dry matter 89.96% and 90.01%,apparent digestibility of crude protein of 60.67% and 66.43%, apparent digestibility of gross energy of90.43% and 91.48%, gross energy metabolizability coefficients of 87.88% and 88.93%, digestible energy values of 3,705 and 3,783 kcal/kg on a dry matter(dM) basis, and metabolizable energy values of 3,600 and 3,676 kcal/kg dM, respectively. The results have demonstrated that integral cassava root silages with wastewater or yogurt have a high nutritional value and can be used as an alternative energy source in growing pig's diets.

关键词： Alternative feed digestibility Energy sources Ensiling Swine

Microbiological biostimulant promotes rooting of olive cuttings

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International Journal of Agricultural and Biological Engineering 2021年第6期14卷 207-212页

作者： Giovana Ritter Fabíola Villa daniel Fernandes da Silva Odair Alberton Fernanda Jaqueline Menegusso Tatiane Eberling Joyce dória Western ParanáState University(Unioeste) Campus Marechal Cândido Rondon.Marechal Cândido RondonPR85960-000Brazil Paranaense University(UNIPAR) UmuaramaPR87502-210Brazil Federal University of Lavras LavrasMG37200-000Brazil

The most widely used method of olive propagation is cutting,although for some cultivars the technique is still *** objective of this work was to evaluate the use of plant growth promoter bacteria and arbuscular mycorrhizal fungi in the rooting of olive *** experiments were conducted from October 2017 to January 2018 with cuttings from 4 olive cultivars(Ascolano 315,Koroneiki,Maria da Féand Picual)from four-year-old *** first experiment consisted of 4 olive cultivars and 3 mycorrhizal species plus the control and the second experiment of 3 concentrations of commercial inoculant(Nitro1000®),containing Azospirillum brasilense plus *** cuttings were treated with 3000 mg/L of indolebutyric acid(IBA).The experimental design used in the two experiments was randomized blocks,in a 4×4 factorial scheme,containing 25 stakes per replicate and 3 *** cuttings were kept under weaver conditions and within a low rooting *** 75 d,the percentage of rooted cuttings,callus and sprouts,length of the largest root,number and length of shoots were *** use of FMA in Maria da Féand Picual has a positive response to cutting rooting and the fungi benefit the quality of the seedlings by the higher number of shoots and larger root *** relation of Azospirillum brasilense cultivar is specific,being that,the cultivar Picual does not respond to inoculation of the bacterium having less viability in the propagation by *** da Féand Koroneiki have the best percentages of rooting with the use of 75.00 and 52.00 mL/L of inoculant,respectively.

关键词： Azospirillum brasilense Arbuscular mycorrhizal fungi Propagation Olea europaea L. microorganism

Numerical simulation of stress behavior of dowel–brick structures in TMSR

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Nuclear Science and Techniques 2020年第5期31卷 77-87页

作者： Hui-Qing Fan Chao-Chao Huang Xiao Wang d.K.L.Tsang Xiao-Chun Zhang Xiao-Yan Wang Shi-Feng Zhu Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China

As essential elements of the graphite reflector in thorium-based molten salt reactor,dowel–brick structures are used to withstand complex working loads in the reactor core and their failure may lead to serious damage of the graphite reactor *** is crucial to investigate the stress behavior of dowel–brick structures for safe operation of the graphite *** this study,three groups of finite element analyses and a strain test were carried out to investigate how the geometric parameters of the dowels affect the stress behavior of the dowel–brick *** numerical results indicate that the stress behavior of a dowel–brick structure is significantly affected by the diameter,length,and aspect ratio of the *** maximum stress in the lower and upper bricks decreases with an increase in the dowel *** location of maximum stress on both lower and upper bricks shifts from the root of the socket to the edge of that socket beside the contact region,as the length of the dowel *** shift of the maximum stress location occurs earlier for the upper bricks than for the lower *** results of strain tests show good agreement with those of numerical analyses.

关键词： dowel–brick structure FEA Stress behavior Strain test

直翅目虫草(肉座菌目):物种多样性及其与寄主的关系

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菌物学报 2020年第4期39卷 707-722页

作者：查岭生叶磊黄仕珂 Saranyaphat Boonmee Prapassorn d.Eungwanichayapant Kevin d.Hyde 文庭池淮北师范大学生命科学学院安徽淮北235000 贵州大学西南药用生物资源教育部工程研究中心贵州贵阳550025 Center of Excellence in Fungal Research Mae Fah Luang UniversityChiang Rai 57100Thailand 中国科学院昆明植物研究所经济植物和生物技术重点实验室云南昆明650201 世界农用林业中心中国和东亚办公室云南昆明650201

迄今为止,以直翅目昆虫为寄主的虫草共报道25种,本研究详细介绍了它们的种类、寄主与分布,并给出了相关的分类学注释。ITS和tef1-α基因联合数据的分子系统发育显示,直翅目虫草分别隶属于白僵菌属Beauveria、绿僵菌属Metarhizium和线虫... 详细信息

迄今为止,以直翅目昆虫为寄主的虫草共报道25种,本研究详细介绍了它们的种类、寄主与分布,并给出了相关的分类学注释。ITS和tef1-α基因联合数据的分子系统发育显示,直翅目虫草分别隶属于白僵菌属Beauveria、绿僵菌属Metarhizium和线虫草属Ophiocordyceps 3个属。基于直翅目昆虫六大类群的生态习性特点,分析并讨论了直翅目虫草物种多样性与寄主的关系。以两种白僵菌Beauveria及戴氏虫草Metacordyceps taii(贵州绿僵菌Metarhizium guizhouense的异名)为例,介绍了虫草的根状菌索,一种介于子实体和孢梗束形体之间的根须状结构。种类修订:蟋螽白僵菌新组合Beauveria grylli ***.≡蟋蟀虫草Cordyceps grylli=Beauveria loeiensis,Beauveria kirkii ***.≡Cordyceps kirkii。寄主更正:蟋螽白僵菌的寄主由原来的蟋蟀成虫(蟋蟀科Gryllidae)更正为螽斯(蟋螽)若虫(蟋螽科Gryllacrididae),蟋蟀线虫草Ophiocordycepstettigonia寄主由原来的螽斯成虫(螽斯科Tettigoniidae:螽斯属Tettigonia)更正为蟋蟀成虫(蟋蟀科)。

关键词：白僵菌属生物防治生态习性螽斯蝗虫新组合分类

一种现代自动控制系统设计并应用于活性污泥法废水处理过程（英文）

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Chinese Journal of Chemical Engineering 2015年第8期23卷 1340-1349页

作者： Alexandros d.Kotzapetros Panayotis A.Paraskevas Athanasios S.Stasinakis Water and Air Quality Laboratory Department of EnvironmentUniversity of the AegeanUniversity Hill

The Activated Sludge Process(ASP) exhibits highly nonlinear properties. The design of an automatic control system that is robust against disturbance of inlet wastewater flow rate and has short process settling times is a challenging matter. The proposed control method is an I-P modi fied controller automatic control system with state variable feedback and control canonical form simulation diagram for the process. A more stable response is achieved with this type of modern control. Settling times of 0.48 days are achieved for the concentration of microorganisms,(reference value step increase of 50 mg·L-1) and 0.01 days for the concentration of oxygen(reference value step increase of 0.1 mg·L-1). Fluctuations of concentrations of oxygen and microorganisms after an inlet disturbance of5 × 103m3·d-1are small. Changes in the reference values of oxygen and microorganisms(increases by 10%, 20% and 30%) show satisfactory response of the system in all cases. Changes in the value of inlet wastewater flow rate disturbance(increases by 10%, 25%, 50% and 100%) are stabilized by the control system in short time. Maximum percent overshoot is also taken in consideration in all cases and the largest value is 25% which is acceptable. The proposed method with I-P controller is better for disturbance rejection and process settling times compared to the same method using PI controller. This method can substitute optimal control systems in ASP.

关键词：自动控制系统控制系统设计活性污泥法污水处理现代化抗干扰能力 PI控制器调整时间

Asymmetric Three-Phase Cascading Trinary-dC Source Multilevel Inverter Topologies for Variable Frequency PWM

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Circuits and Systems 2016年第4期7卷 506-519页

作者： G. Irusapparajan d. Periyaazhagar department of Electrical and Electronics Engineering Mailam Engineering College Mailam India department of Electrical and Electronics Engineering Bharath University Chennai India

Asymmetric three-phase cascading Trinary-dC source Multilevel Inverter which can achieve reduced harmonics and superior root mean square (RMS) values of the output voltage is proposed. This topology can achieve cascaded full bridge inverter operation with dissimilar (unequal) dC Source and it is fired by using variable frequency pulse with modulation technique as a switching strategy. This pulse width modulation switching strategy has a newly adopted multicarrier single reference technique. The performance parameter factors like Form Factor (FF), Crest Factor (CF), Total Harmonic distortion (THd) and fundamental RMS output voltage (VRMS) are estimated by using proposed asymmetrical three-phase cascading multilevel inverter for several modulation indices (0.8 - 1). The research study carries with MATLAB/SIMULINK based simulation and experimental results obtained using appropriate prototype (test board) to prove the viability of the proposed concept.

关键词： Trinary Multilevel Inverter Variable Frequency Pulse Width Modulation Total Harmonic distortions Trinary-dC Source distortion Factor

root uv-b sensitive Mutants Are Suppressed by Specific Mutations in ASPARTATE AMINOTRANSFERASE2 and by Exogenous Vitamin B6

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Molecular Plant 2011年第4期4卷 759-770页

作者： Colin d. Leasure Hong-Yun Tong Xue-Wen Hou Amy Shelton Mike Minton Raymond Esquerra Sanja Roje Hanjo Hellmann Zheng-Hui He department of Biology 1600 Holloway Avenue San Francisco State University San Francisco CA 94132 USA department of Chemistry and Biochemistry 1600 Holloway Avenue San Francisco State University San Francisco CA 94132 USA The Institute of Biological Chemistry Washington State University Pullman WA 99164 USA School of Biological Sciences Washington State University Pullman WA 99164 USA

Vitamin B6 （vitB6） serves as an essential cofactor for more than 140 enzymes. Pyridoxal 5＇-phosphate （PLP）, active cofactor form of vitB6, can be photolytically destroyed by trace amounts of ultraviolet-B （UV-B）. How sun-exposed organisms cope with PLP photosensitivity and modulate vitB6 homeostasis is currently unknown. We previously reported on two Arabidopsis mutants, rusl and rus2, that are hypersensitive to trace amounts of UV-B light. We performed mutagenesis screens for second-site suppressors of the rus mutant phenotype and identified mutations in the ASPARTATE AMINOTRANSFERASE2 （ASP2） gene. ASP2 encodes for cytosolic aspartate aminotransferase （AAT）, a PLP-dependent enzyme that plays a key role in carbon and nitrogen metabolism. Genetic analyses have shown that specific amino acid substitutions in ASP2 override the phenotypes of rusl and rus2 single mutants as well as rusl rus2 double mutant. These substitutions, all shown to reside at specific positions in the PLP-binding pocket, resulted in no PLP binding. Additional asp2 mutants that abolish AAT enzymatic activity, but which alter amino acids outside of the PLP-binding pocket, fail to suppress the rus phenotype. Furthermore, exogenously adding vitB6 in growth media can rescue both rusl and rus2. Our data suggest that AAT plays a role in vitB6 homeostasis in Arabidopsis.

关键词： Vitamin B6 pyridoxal-phosphate aspartate aminotransferase ultraviolet light photo protection.