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Insect Science 2006年第1期13卷 55-60页

作者： ALEXANDRE de ALMEIDA E SILVA ELENICE MOURO VARANDA JOSE RICARDO BAROSELA Laboratorio de Entomologia IPEPATRO RO Brasil departamento de biologia Faculdade de Filosofia Ciencias e Letras de Ribeirao Preto Universidade de Sao Paulo Ribeirao Preto SP Brazil

Biology of the aphid Therioaphis maculata was studied on alfalfa （Medicago sativa L.）, including four resistant （Mesa-Sirsa, CUF101, Baker and Lahontan） and two susceptible （ARC and Caliverde） alfalfa cultivars, and one of the most cropped Brazilian cultivars, Crioula. Under controlled conditions, antibiosis （i.e., reduced longevity, fecundity and increased mortality of the aphid） was observed mainly on the resistant alfalfa cultivars, except on Lahontan. Crioula seemed to be tolerant to aphids. Present data support geographic limitation usage of cultivars, and we suggest Baker and Mesa-Sirsa as sources of antibiosis, and provide biological information of a tropical T. maculata biotype on alfalfa.

关键词： alfalfa cultivars aphid resistance susceptibility Therioaphis maculata

Evaluation of different machine learning methods for land cover mapping of a Mediterranean area using multi-seasonal Landsat images and Digital Terrain Models

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International Journal of Digital Earth 2014年第6期7卷 492-509页

作者： Victor F.Rodriguez-Galiano Mario Chica-Rivas departamento de Geodinamica Universidad de GranadaGranadaSpain departamento de Analisis Matematico Universidad de GranadaGranadaSpain

Land cover monitoring using digital Earth data requires robust classification methods that allow the accurate mapping of complex land cover *** paper discusses the crucial issues related to the application of different up-to-date machine learning classifiers:classification trees(CT),artificial neural networks(ANN),support vector machines(SVM)and random forest(RF).The analysis of the statistical significance of the differences between the performance of these algorithms,as well as sensitivity to data set size reduction and noise were also ***-5 Thematic Mapper data captured in European spring and summer were used with auxiliary variables derived from a digital terrain model to classify 14 different land cover categories in south ***,statistically similar accuracies of over 91%were obtained for ANN,SVM and ***,the findings of this study show differences in the accuracy of the classifiers,being RF the most accurate classifier with a very simple ***,followed by RF,was the most robust classifier to noise and data *** differences in their performances were only reached for thresholds of noise and data reduction greater than 20%(noise,SVM)and 25%(noise,RF),and 80%(reduction,SVM)and 50%(reduction,RF),respectively.

关键词： land cover remote sensing classification trees random forest neural networks support vector machines

Prefoldins Negatively Regulate Cold Acclimation in Arabidopsis thaliana by Promoting Nuclear Proteasome-Mediated HY5 degradation

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Molecular Plant 2017年第6期10卷 791-804页

作者： Carlos Perea-Resa Miguel A. Rodriguez-Milla Elisa Iniesto Vicente Rubio Julio Salinas departamento de biologia Medioambiental Centro de Investigaciones Biologicas CSIC 28040 Madrid Spain departamento de Genetica Molecular de Plantas Centro Nacional de Biotecnologia CSIC 28049 Madrid Spain present address: department of Molecular Biology Massachusetts General Hospital Boston MA 02214 USA Present address: Unidad de Biotecnologia Celular Instituto de Salud Garlos Ⅲ 28222 Madrid Spain

The process of cold acclimation is an important adaptive response whereby many plants from temperate regions increase their freezing tolerance after being exposed to low non-freezing temperatures. The correct development of this response relies on proper accumulation of a number of transcription factors that regulate expression patterns of cold-responsive genes. Multiple studies have revealed a variety of molecular mechanisms involved in promoting the accumulation of these transcription factors. Interestingly, however, the mechanisms implicated in controlling such accumulation to ensure their adequate levels remain largely unknown. In this work, we demonstrate that prefoldins （PFDs） control the levels of HY5, an Arabidopsis transcription factor with a key role in cold acclimation by activating anthocyanin biosynthesis, in response to low temperature. Our results show that, under cold conditions, PFDs accumulate into the nucleus through a deLLA-dependent mechanism, where they interact with HY5, triggering its ubiquitination and subsequent degradation. The degradation of HY5 would result, in turn, in anthocyanin biosynthesis attenuation, ensuring the accurate development of cold acclimation. These findings uncover an unanticipated nuclear function for PFDs in plant responses to abiotic stresses.

关键词： prefoldins cold acclimation Arabidopsis HY5 anthocyanin deLLAs

Pronuclear formation by ICSI using chemically activated ovine oocytes and zona pellucida bound sperm

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Journal of Animal Science and Biotechnology 2017年第2期8卷 370-377页

作者： J.E.Hernández-Pichardo Y.Ducolomb S.Romo M.E.Kjelland R.Fierro F.Casillas M.Betancourt División de Ciencias Biológicas y de la Salud Departamento de Producción Agrícola y AnimalUniversidad Autónoma Metropolitana-XochimilcoCiudad de MexicoMexico Division de Ciencias Biologicas y de la Salud Departamento de Ciencias de la SaludUniversidad Autónoma Metropolitana-IztapalapaSan Rafael Atlixco 186CP 09340 Ciudad de MexicoMexico departamento de Ciencias Pecuarias Facultad de EstudiosSuperiores CuautitlanUNAMCiudad de MexicoEstado de MexicoMexico Conservation Genetics&BiotechLLCValley CityNDUSA Division de Ciencias Biologicas y de la Salud Departamento de Biologia de la ReproduccionUniversidad Autonoma Metropolitana-lztapalapaCiudad de MexicoMexico Doctorado en biologia Experimental Universidad Autonoma Metropolitana-lztapalapaCiudad de MexicoMexico

Background： In order to improve ICSI, appropiate sperm selection and oocyte activation is necessary. The objective of the present study was to determine the efficiency of fertilization using ICSI with chemically activated ovine oocytes and sperm selected by swim up（SU） or swim up ＋ zona pellucida（SU ＋ ZP） ***： Experiment 1, 4–20 replicates with total 821 in vitro matured oocytes were chemically activated with ethanol, calcium ionophore or ionomycin, to determine oocyte activation（precense of one PN）. Treatments showed similar results（54, 47, 42 %, respectively） but statistically differents（P 0.05）.Conclusions： Chemical activation induces higher ovine oocyte activation than mechanical activation. Ethanol slightly displays higher oocyte activation than calcium ionophore and ionomicine. Sperm selection with SU ＋ ZP increased AR/A and AR/D rates in comparison with SU in fresh and frozen-thawed sperm. According to this, in terms of fertilization rates, chemical activation after ICSI increased oocyte PN formation compared to mechanical activation. Also, fresh sperm treated with SU and SU ＋ ZP were significantly different than frozen-thawed sperm,but between sperm treatments no significant differences were obtained.

关键词： Ethanol ICSI Oocyte activation Ovine Pronucleus Zona pellucida

Assessing the relationship between the rumen microbiota and feed efficiency in Nellore steers

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Journal of Animal Science and Biotechnology 2021年第4期12卷 1645-1661页

作者： Déborah Romaskevis Gomes Lopes Márcio de Souza Duarte Alex J.La Reau Ibrahim Zuniga Chaves Tiago Antônio de Oliveira Mendes Edenio detmann Cláudia Braga Pereira Bento Maria Eugênia Zerlotti Mercadante Sarah Figueiredo Martins Bonilha Garret Suen Hilário Cuquetto Mantovani departamento de microbiologia Universidade Federal de ViçosaViçosaMG 36570-900Brazil departamento de Zootecnia Universidade Federal de ViçosaViçosaMinas GeraisBrazil department of Bacteriology University of Wisconsin-MadisonMadisonWIUSA departamento de Bioquímia e biologia Molecular Universidade Federal de ViçosaViçosaMinas GeraisBrazil Instituto de Zootecnia Centro APTA Bovinos de CorteSertãozinhoSão PauloBrazil

Background:Ruminants rely upon a complex community of microbes in their rumen to convert host-indigestible feed into ***,little is known about the association between the rumen microbiota and feed efficiency traits in Nellore(Bos indicus)cattle,a breed of major economic importance to the global beef ***,we compare the composition of the bacterial,archaeal and fungal communities in the rumen of Nellore steers with high and low feed efficiency(FE)phenotypes,as measured by residual feed intake(RFI).Results:The Firmicutes to Bacteroidetes ratio was significantly higher(Pmicrobiota of highefficiency ***,analysis of rumen fermentation variables and functional predictions indicated similar metabolic outputs for the microbiota of distinct FE ***:Our results demonstrate that differences in the ruminal microbiota of high and low FE Nellore steers comprise specific taxa from the bacterial,archaeal and fungal *** OTUs belonging to the genus Piromyces were identified in animals showing high feed efficiency,whereas among archaea,Methanobrevibacter was associated with steers classified as *** identification of specific RFI-associated microorganisms in Nellore steers could guide further studies targeting the isolation and functional characterization

关键词： Beef cattle ITS1 region Next-generation sequencing RFI Rumen microbiota 16S rRNA gene

Strategies for the analysis of single-tree plot experiments in Eucalyptus plantations

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Journal of Forestry Research 2021年第6期32卷 2437-2445页

作者： Heloisa Guimaraes Santos Flavia Maria Avelar Goncalves Jose Luis Lima Aurelio Mendes Aguiar Gabriel dehon Sampaio Pecanha Rezende Bruno Marco de Lima Magno Antonio Patto Ramalho departamento de biologia Setor de Genetica E Melhoramento de PlantasUniversidade Federal de Lavras-UFLALavrasMGBrasil Suzano Papel E Celulose Sao PauloSPBrasil Bracell SP Celulose Ltda Lencóis PaulistaSPBrasil

To verify if the response by Eucalyptus clones in a single-tree plot is influenced by neighboring plants and to determine the effect of missing and/or dominated plants,seven eucalyptus trials in four Brazilian states were analyzed in a randomized complete block design with one plant/plot and 30 *** annual increment(MAI,m^(3)ha^(-1)per year)was determined for three-year-old *** influence of neighboring clones was estimated by a linear regression coefficient between the MAI of each clone/plot and the average of a clonal MAI and its eight *** determine the effect of missing and/or dominated trees,a correction between the MAI and the area available/plant was *** analysis considered unadjusted and adjusted data for missing and dominated *** of accuracy and index of coincidence were used to compare the *** single-tree plots,clone performances were not influenced by neighboring *** accuracy was not increased by any of the adjustments employed and the clone ranking was not altered,and therefore did not justify their use.

关键词： Single-tree plot Missing plant adjustment Eucalyptus breeding

Golden Ratio Sinusoidal Sequences and the Multimode Pulsation of the δ Sct Star V784 Cassiopeiae

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Chinese Journal of Astronomy and Astrophysics 2004年第4期4卷 343-348页

作者： JuanGarcíaEscudero departamento de Fisica Universidad de Oviedo33007-Oviedo Spainon

Non periodic ordered sequences obtained by production rules in formal grammars are applied to the analysis of the multi-periodicity of the δ-Scuti type variable star V784 Cas. An artificial light curve for V784 Cas is generated by a non deterministic derivation in a context-sensitive grammar by concatenation of two sinusoidal fragments following certain word sequences. The two basic building blocks represent temporal segments in a golden ratio and the number of long and short segments in a word are also in a golden ratio.

关键词： stars:variables:δScuti-stars:individual:V784 Cas

The ability of sperm selection techniques to remove single- or double-strand DNA damage

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Asian Journal of Andrology 2011年第5期13卷 764-768页

作者： Maria Enciso Miriam Iglesias Isabel Galan Jonas Sarasa Antonio Gosalvez Jaime Gosalvez Unidad de Genetica Departamento de Biologia Universidad Aut6noma de Madrid Madrid 28049 Spain Unidad de Reproducci6n Asistida Hospital Quir6n Madrid Madrid 28223 Spain

A wide variety of techniques for the preparation of sperm are currently available, of which the most commonly employed are densitygradient centrifugation （DGC） and swim-up （SUP）. To date, these methods appear to be effective in selecting functional sperm for assisted reproduction techniques （ART）, but they may have negative effects on sperm DNA. In this study, the ability of these semen processing techniques to eliminate spermatozoa containing single- and double-strand DNA damage was assessed by the two-tailed comet assay and the sperm chromatin dispersion test in 157 semen samples from patients seeking assisted reproduction treatment. Our results indicated that SUP and DGC are equally efficient in eliminating spermatozoa containing double-strand DNA damage and sperm with highly damaged （degraded） DNA, as characterized by the presence of both single- and double-strand DNA breaks. However, DGC is more efficient than SUP in selecting spermatozoa that are free from single-strand DNA damage. Future studies should characterise the importance of the various types of DNA damage and examine the sperm processing protocols used in each laboratory to determine their ability to eliminate DNA damage and hence, prevent the potential transmission of genetic mutations via ART.

关键词： density-gradient centrifugation male factor sperm chromatin dispersion sperm DNA fragmentation swim-up

THE BANACH-LIE GROUP OF LIE TRIPLE AUTOMORPHISMS OF AN H^＊-ALGEBRA^＊

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Acta Mathematica Scientia 2010年第4期30卷 1219-1226页

作者： A.J.Calderón Martín C.Martín González departamento de Matemáticas Universidad de Cádiz departamento de Algebra Geometría y Topología Universidad de Málaga

We study the Banach-Lie group Ltaut（A） of Lie triple automorphisms of a complex associative H^＊-algebra A. Some consequences about its Lie algebra, the algebra of Lie triple derivations of A, Ltder（A）, are obtained. For a topologically simple A, in the infinite-dimensional case we have Ltaut（A）0 = Aut（A） implying Ltder（A） = der（A）. In the finite-dimensional case Ltaut（A）0 is a direct product of Aut（A） and a certain subgroup of Lie derivations δ from A to its center, annihilating commutators.

关键词： Banach-Lie group Lie triple automorphism Lie triple derivation

Strong Connections and Invertible Weak Entwining Structures

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Acta Mathematica Sinica,English Series 2012年第7期28卷 1443-1460页

作者： J. N. ALONSO LVAREZ J. M. FERN NdeZ VILABOA GONZ LEZ RODR íGUEZ departamento de Matemáticas Universidad de VigoCampus Universitario Lagoas-Marcosende departamento de lxebra Universidad de Santiago de Compostela departamento de Matemática Aplicada Ⅱ Universidad de VigoCampus Universitario Lagoas-Marcosende

In this paper we obtain a criterion under which the bijectivity of the canonical morphism of a weak Galois extension associated to a weak invertible entwining structure is equivalent to the existence of a strong connection form. Also we obtain an explicit formula for a strong connection under equivariant projective conditions or under coseparability conditions.

关键词： Monoidal category invertible weak entwining structure strong connection weak Galois extension