Arroz de terras altas no sistema plantio direto.

O presente trabalho foi conduzido com o objetivo de adequar o cultivo do arroz no Sistema Plantio Direto pela adoção de semeadoras e de genótipos mais adaptados ao sistema.bitstream/CNPAF/19921/1/comt_47.pd

Arroz de terras altas: espaçamento e densidade de semeadura.

Em estudos conduzidos no município de Santo Antônio de Goiás, GO, na Fazenda Lorena, no ano agrícola 2002-2003, no Sistema Plantio Convencional, após pastagem, observou-se que os genótipos de arroz de terras altas, com arquitetura moderna, CNA 8557, BRS Talento, BRS Bonança, BRS Primavera e BRS Soberana foram mais produtivas no espaçamento de 30 cm entrelinhas, comparativamente aos espaçamentos de 20, 40 e 50 cm.bitstream/item/60519/1/CIR61.pd

Tendências genéticas e fenotípicas para características indicadoras de eficiência reprodutiva em bovinos da Raça Nelore sob seleção para precocidade sexual.

Resumo: As características reprodutivas estão diretamente relacionadas à eficiência econômica dos sistemas de produção de bovinos de corte. Assim, objetivou-se com este estudo estimar as tendências genéticas e fenotípicas entre características de reprodução e idade à primeira concepção e ao primeiro parto, em um rebanho Nelore sob seleção para precocidade sexual. Os componentes de (co)variância foram obtidos utilizando-se o método de Máxima Verossimilhança Restrita, disponível no pacote BLUPF90, em análises uni e bicaracterísticas, sob modelo animal. Para o cálculo das tendências genéticas através da regressão foram utilizados os valores genéticos anuais médios em relação ao ano de nascimento pelo PROC REG do SAS, seguindo tendência linear e quadrática. E a tendência fenotípica da população usando os valores fenotípicos. As tendências genéticas foram -0,03 dias/ano para PS, -0,14 dias/ano para IDP, -0,12 meses/ano para IPC e -0,16 meses/ano para IPP. A seleção para precocidade sexual, tendo como critério de seleção IPC ou IPP, promoverá melhoria na eficiência reprodutiva e fertilidade do rebanho. Abstract: The reproductive traits are directly related to the economic efficiency of beef cattle production systems. Thus, the aim of this study was to estimate the genetic parameters and the genetic and phenotypic trends for reproductive traits and age at first conception and first calving in a Nellore cattle herd under selection for sexual precocity. The covariance components were estimated using the Restricted Maximum Likelihood method, available on BLUPF90 package, in univariate and bivariate analyzes using animal model. For the calculation of the genetic trends through the regression the PROC REG of the SAS, following a linear and quadratic tendency used the average annual genetic values in relation to the year of birth. The phenotypic trend of the population using the phenotypic values. The genetic trends were -0.03 days/year for DO, -0.14 days/year for CI, -0.12 months /year for AFCo and -0.16 months/year for AFCa. Selection for sexual precocity based on AFCo and AFCa shall promote improvement in reproductive efficiency and fertility

Parâmetros genéticos para características de composição de carcaça em bovinos da raça Nelore sob seleção para precocidade sexual.

Resumo: Objetivou-se, com este estudo, estimar os parâmetros genéticos para características de composição de carcaça e idade à primeira concepção (IPC) e ao primeiro parto (IPP), em um rebanho da raça Nelore sob seleção para precocidade sexual. Foram estimados os parâmetros genéticos para as características peso da caraça quente (PCQ), peso da porção comestível (PPC), IPC e IPP. Os componentes de (co)variância foram obtidos pelo método de Máxima Verossimilhança Restrita, disponível no pacote BLUPF90, em análises uni e bicaracterísticas, utilizando o modelo animal. As estimativas de herdabilidade foram de 0,39 (PCQ), 0,39 (PPC), 0,21 (IPC) e 0,24 (IPP). As características indicadoras de precocidade sexual apresentaram coeficientes de correlação genética entre -0,45 a -0,40 com as características de composição frigorífica. A seleção para precocidade sexual com base na idade à primeira concepção deverá promover mudanças genéticas no sentido contrário na s características de composição de carcaça. Abstract: The aim of this study was to estimate the genetic parameters carcass composition traits and age at first conception (AFCo) and first calving (AFCa), in a Nellore cattle herd under selection for sexual precocity. Genetic parameters were estimated for hot carcass weight (HCW), weight of edible portion (WEP), AFCo and AFCa. The covariance components were estimated using the Restricted Maximum Likelihood method, available on BLUPF90 package, in univariate and bivariate analyzes using animal model. The heritability estimated for 0.39 (HCW), 0.39 (WEP), 0.21 (AFCo) and 0.24 (AFCa). The traits that indicate sexual precocity showed genetic correlation coefficients ranging from -0.45 to -0.40 with carcass composition traits, respectively. Selection for sexual precocity based on age the first conception shall promote opposite direction genetic changes on carcass composition traits

Inclusive Search for Anomalous Production of High-pT Like-Sign Lepton Pairs in Proton-Antiproton Collisions at sqrt{s}=1.8 TeV

We report on a search for anomalous production of events with at least two charged, isolated, like-sign leptons with pT > 11 GeV/c using a 107 pb^-1 sample of 1.8 TeV ppbar collisions collected by the CDF detector. We define a signal region containing low background from Standard Model processes. To avoid bias, we fix the final cuts before examining the event yield in the signal region using control regions to test the Monte Carlo predictions. We observe no events in the signal region, consistent with an expectation of 0.63^(+0.84)_(-0.07) events. We present 95% confidence level limits on new physics processes in both a signature-based context as well as within a representative minimal supergravity (tanbeta = 3) model.Comment: 15 pages, 4 figures. Minor textual changes, cosmetic improvements to figures and updated and expanded reference

Measurements of branching fraction ratios and CP-asymmetries in suppressed B^- -> D(-> K^+ pi^-)K^- and B^- -> D(-> K^+ pi^-)pi^- decays

We report the first reconstruction in hadron collisions of the suppressed decays B^- -> D(-> K^+ pi^-)K^- and B^- -> D(-> K^+ pi^-)pi^-, sensitive to the CKM phase gamma, using data from 7 fb^-1 of integrated luminosity collected by the CDF II detector at the Tevatron collider. We reconstruct a signal for the B^- -> D(-> K^+ pi^-)K^- suppressed mode with a significance of 3.2 standard deviations, and measure the ratios of the suppressed to favored branching fractions R(K) = [22.0 \pm 8.6(stat)\pm 2.6(syst)]\times 10^-3, R^+(K) = [42.6\pm 13.7(stat)\pm 2.8(syst)]\times 10^-3, R^-(K)= [3.8\pm 10.3(stat)\pm 2.7(syst]\times 10^-3, as well as the direct CP-violating asymmetry A(K) = -0.82\pm 0.44(stat)\pm 0.09(syst) of this mode. Corresponding quantities for B^- -> D(-> K^+ pi^-)pi^- decay are also reported.Comment: 8 pages, 1 figure, accepted by Phys.Rev.D Rapid Communications for Publicatio

Evidence for t\bar{t}\gamma Production and Measurement of \sigma_t\bar{t}\gamma / \sigma_t\bar{t}

Using data corresponding to 6.0/fb of ppbar collisions at sqrt(s) = 1.96 TeV collected by the CDF II detector, we present a cross section measurement of top-quark pair production with an additional radiated photon. The events are selected by looking for a lepton, a photon, significant transverse momentum imbalance, large total transverse energy, and three or more jets, with at least one identified as containing a b quark. The ttbar+photon sample requires the photon to have 10 GeV or more of transverse energy, and to be in the central region. Using an event selection optimized for the ttbar+photon candidate sample we measure the production cross section of, and the ratio of cross sections of the two samples. Control samples in the dilepton+photon and lepton+photon+\met, channels are constructed to aid in decay product identification and background measurements. We observe 30 ttbar+photon candidate events compared to the standard model expectation of 26.9 +/- 3.4 events. We measure the ttbar+photon cross section to be 0.18+0.08 pb, and the ratio of the cross section of ttbar+photon to ttbar to be 0.024 +/- 0.009. Assuming no ttbar+photon production, we observe a probability of 0.0015 of the background events alone producing 30 events or more, corresponding to 3.0 standard deviations.Comment: 9 pages, 3 figure

Precision Top-Quark Mass Measurements at CDF

We present a precision measurement of the top-quark mass using the full sample of Tevatron $\sqrt{s}=1.96$ TeV proton-antiproton collisions collected by the CDF II detector, corresponding to an integrated luminosity of 8.7 $fb^{-1}$. Using a sample of $t\bar{t}$ candidate events decaying into the lepton+jets channel, we obtain distributions of the top-quark masses and the invariant mass of two jets from the $W$ boson decays from data. We then compare these distributions to templates derived from signal and background samples to extract the top-quark mass and the energy scale of the calorimeter jets with {\it in situ} calibration. The likelihood fit of the templates from signal and background events to the data yields the single most-precise measurement of the top-quark mass, \mtop = 172.85 \pm$0.71 (stat)$\pm$0.85 (syst) GeV/c^{2}.$Comment: submitted to Phys. Rev. Let