908 research outputs found
W Pair Production at the LHC - I. Virtual O(alpha_s^2) Corrections in the High Energy Limit
We present the result for the two-loop and the one-loop squared virtual QCD
corrections to the W boson pair production in the quark-anti-quark-annihilation
channel in the limit where all kinematical invariants are large compared to the
mass of the W boson. The infrared pole structure is in agreement with the
prediction of Catani's general formalism for the singularities of two loop
amplitudes.Comment: 22 pages, 1 figure, references added, typos corrected, final version
as publishe
Estudio comparativo entre la madera de pino y de eucalipto para diversas tipologías estructurales
El presente trabajo aborda el análisis de los datos obtenidos fruto del cálculo de diversas tipologías estructurales realizadas en madera de Eucalyptus globulus Labill. en comparación con aquellas realizadas en madera de Pinus sylvestris L. que tradicionalmente se viene empleando.
Para poder extraer unas conclusiones fiables sobre la comparativa entre las especies, se han estudiado diversas tipologías estructurales diferenciándose dos grupos: cubiertas y forjados. En cuanto a cubiertas se refiere, se ha planteado el estudio de la cercha denominada “cercha de pendolón y tornapuntas”. Para ello se han propuesto distintas luces y acciones. Por otra parte las viguetas de forjado se han obtenido suponiendo diversas luces de cálculo.
El estudio de aquellas piezas de carácter estructural secundario, como correas y viguetas de forjado pone de manifiesto las excelentes propiedades mecánicas de la madera de eucalipto, arrojando unos valores de sección resistente menores que los obtenidos con los sistemas estructurales homólogos realizados en madera de conífera. Para la estructura principal, el trabajo presenta las diferencias de dimensionado para los casos estudiados ya que las conclusiones se centran en la especificidad de cada caso.______________________________________The present work approaches the analysis of the obtained information fruit of the calculation of diverse structural kinds realized in wood of Eucalyptus globulus Labill. in comparison with those realized in wood of Pinus sylvestris L. that traditionally one comes using.
To be able to extract a few trustworthy conclusions on the comparative one between the species, diverse structural kinds have been studied differentiating two groups: roofs and floors. As for roofs it refers, there has appeared the study of the truss. For it they have proposed different lengths and loads. On the other hand the joists of floor have been obtained supposing diverse lengths.
The study of those pieces of structural secondary character as joists of floor, it puts of manifest the excellent mechanical properties of the wood of eucalyptus, throwing a few minor values of resistant section that the obtained ones with the structural systems counterparts realized in wood of coniferous. For the main frame, the work presents the differences of sizes for the studied cases since the conclusions depend on the each case
Detection and molecular characterization of Grapevine yellow speckle viroid 1 isolates infecting grapevines in Brazil.
Presently, Hop stunt viroid(HSVd) and Citrus exocortis viroid (CEVd) are the only viroids reported to infect grapevines (Vitis spp.) in Brazil, among the seven viroid species already reported infecting this host in other countries. All grapevine viroid diseases are graft-transmissible and can induce losses especially when associated with viruses. The aim of this work was to confirm infection by Grapevine yellow speckle viroid 1(GYSVd-1) in grapevine samples exhibiting yellow speckle symptoms in the leaves and in asymptomatic samples sequenced by next generation sequencing (NGS). The occurrence of this viroid in Brazil was further investigated in a second study. Total RNAs and dsRNAs were extracted from five symptomatic plants and 16 asymptomatic samples, respectively. Specific primers were used for RT-PCR and amplified DNA fragments were cloned and sequenced by the Sanger method. Eleven complete nucleotide sequences of GYSVd-1 isolates (366 ?367 nt) were obtained from NGS and from RT-PCR amplicons. Comparisons showed high identities (95.9 ?100 %) among ten isolates and an identity of 87.2 ?90.4 % with a divergent isolate (RM-BR). Phylogenetic analyses placed GYSVd-1 isolates in four clusters (types 1, 2, 3 and 4). All GYSVd-1 infections were confirmed by conventional RT-PCR and RT-qPCR using specific oligonucleo-tides and a labeled probe. This is the first report and molecular characterization of GYSVd-1 infecting grapevines in Brazil, and our survey indicates that this viroid could be widespread in the major grape producing regions of Brazil. Keywords GYSVd-1 . Incidence . Next generation sequencing. Secondary structure. Vine
Detecção e caracterização molecular dos genes da proteína capsidial de ilarvírus e ampelovírus que infectam fruteiras temperadas.
Dentre os principais patógenos que incidem em fruteiras temperadas, destacam-se o Prune dwarf virus (PDV), o Apple mosaic virus (ApMV) e o Grapevine leafroll-associated virus 1 (GLRaV-1). Neste trabalho foram realizadas a detecção e a caracterização molecular dos genes da proteína capsidial de isolados destas três espécies virais. RNAs totais foram extraídos de amostras de folhas de pessegueiros, macieiras e videiras e, nas reações de RT-PCR, foram utilizados oligonucleotídeos específicos para cada espécie viral. Os cDNAs amplificados foram clonados e sequenciados. Foram verificadas altas identidades entre as sequências de nucleotídeos dos genes da proteína capsidial dos isolados brasileiros de PDV, ApMV e GLRaV-1 e isolados de outros países, independente da origem geográfica e da hospedeira. O peso molecular da proteína capsidial destes vírus foi estimado por meio de Western blot em cerca de 24kDa (PDV), 26kDa (ApMV) e 39kDa (GLRaV-1).Nota técnica
First report of grapevine pinot gris virus infecting grapevine in Brazil.
Grapevine Pinot gris virus (GPGV) has been re-ported infecting grapevines (Vitisspp.) in several countriesof the world. In this study, 19.5% of grapevine samples col-lected in Brazil and indexed for GPGV by RT-qPCR wasinfected. The complete coat protein and the partial replicase genes of two Brazilian isolates (CF-BR and ME-BR) were sequenced and exhibited very high nucleotide and deduced amino acid identities with many foreign characterized isolates of GPGVavailable in the GenBank. This is the first detection of GPGV infecting grapevines in Brazil. Keywords GPGV . Trichovirus . RT-qPCR . Real time RT-PCR. Diagnosis.Disponível em: . Acesso em: 04 set. 2017
Lagarta-enroladeira da macieira Bonagota cranaodes (Meyrick, 1937) (Lepidoptera:Tortricidae): bioecologia, monitoramento e controle.
bitstream/item/40824/1/cir24.pd
Correlation between bioassayed plasma levels of FK 506 and lymphocyte growth from liver transplant biopsies with histological evidence of rejection.
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