A escolha da forrageira para a formação de pastagens.

bitstream/item/39332/1/A-escolha-da-forrageira-para-a-formacao-de-pastagens-Portal-Dia-de-Campo.pd

A pecuária e os gases de efeito estufa.

bitstream/item/39331/1/A-pecuaria-e-os-gases-de-efeito-estufa-Portal-Dia-de-Campo.pd

Pastagens: mitos e realidades.

bitstream/item/39330/1/Pastagens-mitos-e-realidades-Portal-Dia-de-Campo.pd

Como estimar o que engorda o boi.

bitstream/item/39327/1/Como-estimar-o-que-engorda-o-boi-Portal-Dia-de-Campo.pd

A biotecnologia e as forrageiras tropicais.

bitstream/item/39155/1/A-biotecnologia-e-as-forrageiras-tropicais-Portal-Dia-de-Campo.pd

Non-Gaussian Geostatistical Modeling using (skew) t Processes

We propose a new model for regression and dependence analysis when addressing spatial data with possibly heavy tails and an asymmetric marginal distribution. We first propose a stationary process with $t$ marginals obtained through scale mixing of a Gaussian process with an inverse square root process with Gamma marginals. We then generalize this construction by considering a skew-Gaussian process, thus obtaining a process with skew-t marginal distributions. For the proposed (skew) $t$ process we study the second-order and geometrical properties and in the $t$ case, we provide analytic expressions for the bivariate distribution. In an extensive simulation study, we investigate the use of the weighted pairwise likelihood as a method of estimation for the $t$ process. Moreover we compare the performance of the optimal linear predictor of the $t$ process versus the optimal Gaussian predictor. Finally, the effectiveness of our methodology is illustrated by analyzing a georeferenced dataset on maximum temperatures in Australi

Selection of Interspecific Hybrids of Brachiaria-A Tropical Forage Grass

The aim of the breeding program at the National Beef Cattle Research Center (CNPGC) of the Brazilian Corporation for Agricultural Research (EMBRAPA), is to produce vigorous apomictic hybrids with wide edaphic adaptation, good production and nutritive value combined with spittlebug (Homoptera:Cercopidea) resistance. Fiftysix superior hybrids were selected based on visual estimates of vigor, leafiness, tolerance to drought and natural spittlebug infestation in the field. These were characterized for mode of reproduction, spittlebug reaction under controlled conditions and for morphological diversity using nine selected traits. Multivariate analysis classified the population into seven groups where the hybrids were clearly intermediate in plant architecture when compared to parental types. Eight hybrids displayed resistance to spittlebug under controlled conditions and sixteen were found to be susceptible. Twenty seven reproduce sexually and twenty five are apomictic. Their potential as new cultivars will be determined following agronomical evaluation and grazing studies

Protocolos para assepsia de meristemas e cultura de tecidos para o gênero Brachiaria (Trin.) Griseb e melhor tratamento para duplicação de número cromossômico.

O objetivo neste trabalho é divulgar os protocolos utilizados na Embrapa Gado de Corte para a assepsia e micropropagação in vitro de explantes de braquiária. Estes foram coletados in vivo para a cultura de tecidos, com a finalidade de otimizar a micropropagação e a poliploidização de genótipos diplóides. A metodologia utilizada resultou na duplicação somática efetiva de algumas plantas do gênero. O domínio dessas técnicas contribui extraordinariamente para a economia de tempo e espaço em obter genótipos valiosos ao programa de melhoramento da referida gramínea. Plantas duplicadas permitirão o melhoramento intra-específico nesse gênero, caracterizado por plantas apomíticas tetraplóides de grande importância agronômica.bitstream/CNPGC-2009-09/12404/1/DOC169.pd

Electrostatic control of quantum dot entanglement induced by coupling to external reservoirs

We propose a quantum transport experiment to prepare and measure charge-entanglement between two electrostatically defined quantum dots. Coherent population trapping, as realized in cavity quantum electrodynamics, can be carried out by using a third quantum dot to play the role of the optical cavity. In our proposal, a pumping which is quantum mechanically indistinguishable for the quantum dots drives the system into a state with a high degree of entanglement. The whole effect can be switched on and off by means of a gate potential allowing both state preparation and entanglement detection by simply measuring the total current.Comment: 5 pages, 4 figures, Latex2e with EPL macros, to appear in Europhysics Letter