Cultivo de repolho (Brassica oleracea var. Capitata) no Acre.

O repolho (Brassica oleracea var. Capitata) é, economicamente, a hortaliça mais importante da família das brássicas. Constitui uma excelente fonte de sais minerais, principalmente cálcio e fósforo, além de vitaminas A, B e C, sendo também, um alimento bastante versátil à mesa e de fácil digestão. O baixo conteúdo de açúcares permite o consumo de 100g diárias, sem prejuízos às pessoas diabéticas. Na família das brássicas é a hortaliça de maior teor de vitamina C. A composição nutritiva varia com fatores ambientais, irrigação, adubação, estágio de desenvolvimento na colheita, métodos de estocagem, processamento caseiro e industrial e cultivares. Na medicina natural é usado como estimulante do crescimento de cabelo, nevralgias faciais e dentárias, úlceras internas, distúrbios intestinais, reumatismo, hemorróidas, tuberculose e tumores. É uma cultura que mundialmente apresenta evolução em área cultivada, rendimento e produção. No Estado do Acre isso também pode ocorrer com o advento de cultivares adaptados à temperatura elevada e disponibilidade de tecnologia de produção. O objetivo deste trabalho é fornecer orientações técnicas para o cultivo do repolho, geradas pela pesquisa com resultados para o produtor acreano.bitstream/item/163303/1/968.pd

The finiteness of the four dimensional antisymmetric tensor field model in a curved background

A renormalizable rigid supersymmetry for the four dimensional antisymmetric tensor field model in a curved space-time background is constructed. A closed algebra between the BRS and the supersymmetry operators is only realizable if the vector parameter of the supersymmetry is a covariantly constant vector field. This also guarantees that the corresponding transformations lead to a genuine symmetry of the model. The proof of the ultraviolet finiteness to all orders of perturbation theory is performed in a pure algebraic manner by using the rigid supersymmetry.Comment: 23 page

Efeito da idade da vaca sobre o peso ao nascimento e peso à desmama de bezerros criados extensivamente na sub-região do Paiaguás, Pantanal Sul-Mato-Grossense.

O estudo foi realizado com intuito de avaliar o efeito da idade da vaca ao parto sobre os pesos de bezerros ao nascimento e a desmama corrigidos para os 205 dias de idade, de um rebanho comercial de bovinos de corte anelorados, pertencentes a uma propriedade particular que realiza a atividade de cria extensiva em pasto nativo e está localizada na sub-região do Paiaguás, Pantanal Sul-Mato-Grossense. Utilizou-se informações de peso ao nascimento e peso à desmama corrigidos para os 205 dias de idade de 183 animais, assim como informações da idade da vaca ao parto. Foram realizadas análises de regressão para avaliar o efeito da idade da vaca ao parto sobre as características em estudo. A idade da vaca ao parto influenciou significativamente sobre as características de peso ao nascimento e peso à desmama corrigido para os 205 dias de idade. Tanto para peso ao nascer quanto para peso à desmama aos 205 dias, as idades iniciais e finais das vacas apresentaram resultados abaixo da média estimada. Deste modo, há necessidade de considerar o efeito da idade da vaca ao parto sobre as características produtivas, para que os animais, candidatos à seleção, tenham seus valores genéticos preditos com maior confiabilidade, garantindo assim maximização do ganho genético, por meio da seleção dos melhores reprodutores

Microstresses and microstructure in thick cobalt-based laser deposited coatings

Microstresses in a thick laser clad Co-based coating on steel substrate were investigated with 3D X-ray microscopy using an intense synchrotron microfocused beam. The microstructure was examined with tight microscopy and field emission scanning electron microscopy equipped with X-ray energy dispersive spectroscopy and Electron Back Scattering Diffraction (orientation imaging microscopy). Microhardness and scratch resistance variations inside the coating are related to the local microstructure influenced by additional heating and by melt convection during the laser track overlapping. The residual microstrains were accessed with a high spatial resolution defined by the size of the synchrotron microbeam. Type 11 residual strains and stresses on the level of individual grains and dendrites were analyzed in terms of tensor invariants, hydrostatic and von Mises shear stress, along the depth of a slightly diluted clad track. The upper part of the coating shows a constant spread of hydrostatic stresses between -500 and 500 MPa; towards the bottom of the track the spread of these stresses increases almost linearly with depth. A correlation between the microstructural features and the spread of the hydrostatic microstresses was found. It is concluded that microstresses in individual neighboring grains are inhomogeneously dispersed. (c) 2007 Elsevier B.V. All rights reserved

Beef cattle stocking rate, a key to the conservation of the pastoral system in Brazilian biomes.

Abstract: In Brazil, beef cattle are raised in predominantly extensive systems. The feeding base is represented by native and/or cultivated pastures. The latter may be in a well conserved state or may present some degree of degradation. The amount of animals per hectare, supported by the pasture by each time unit, is basically related to the pasture production. There is interaction between quality and production, and changes in these parameters are strongly affected by the stocking rate. Therefore, the adjustment in the stocking rate is the most important management factor and the main determinant of animal production and pasture composition. Municipal data from the 2006 agriculture and cattle raising business census were considered with the objective to analyze, by means of typologies, the use of pastoral areas in Brazil. In the census, the producers declared their pastoral areas according to the following classification: native pasture areas (PN), cultivated pasture areas in good conservation status (PC) and cultivated pasture areas with some degree of degradation (PCD). They also indicated the number of bovine in each type of pasture. The data were submitted to exploratory factorial analysis, with varimax rotation. The first two factors (extracted by main components) explained 0.83 of the (co)variance, and the estimate of the Kaiser-Mayer-Olkin (KMO) adequacy test was 0.76, which meant good adjustment of the variables selected. The commonalities of the variables selected, PN area; total pasture area (TP), bovines in PN (Bov_PN); bovines in PCD area (Bov_PCD); bovines in PC area (Bov_PC); bovines in total pasture area (Bov_APT); and the stocking rate (TxLota) were 0.65; 0.97; 0.77; 0.74; 0.79; 0.87; and 0.99, respectively. The first factor was associated with the variables PN, TP, Bov_PN, Bov_PCD, Bov_PC, and Bov_APT, which directs to the latent variable correlated to those municipalities with large pasture areas, in general, and also with the largest cattle population. The variable TxLota presented the most significant factorial load in the second factor, that is, all those municipalities with the greatest concentration of cattle per unit area are represented in the second factor. The municipalities that were best represented in factor_1 are different from the ones represented in factor_2. The non-parametric correlation between the classifications of the two groups of municipalities formed by the factorial scores in the first and the second factors is small (0,24). This indicates that the context of those municipalities with the highest stocking rate is a lot different from the ones with the largest areas and cattle herds. The application of livestock development policies in the different Brazilian biomes should take into account all the distinguishing features of the municipalities, regarding their context, especially the pasture areas and their vocation for primary livestock production.ICAS VI

Effects of pulsed electric field-assisted osmotic dehydration and edible coating on the recovery of anthocyanins from in vitro digested berries

Berry fruits, such as strawberries and blueberries, are rich sources of anthocyanins. Several studies have been made on the impact of non-thermal treatments on safety, shelf-life and nutritional characteristics of such products, but the effects of these processes on anthocyanin stability during digestion in the gastrointestinal tract are still not completely clear. The aim of this study was to assess the recovery of anthocyanins after simulated gastrointestinal digestion of (1) strawberry samples, pre-treated with pulsed electric field (PEF) at 100 or 200 V\ub7cm 121, prior to osmotic dehydration (OD), and (2) blueberry samples coated with chitosan and procyanidin. After digestion, a significantly higher content of cyanidin-3-O-glucoside and malvidin-3-O-glucoside was quantified by LC-MS/MS in processed strawberry and blueberry samples, compared with the controls. The highest recovery of cyanidin-3-O-glucoside was detected in digested strawberry samples osmotically dehydrated with trehalose. The recovery of malvidin-3-O-glucoside was highest in digested blueberries coated with chitosan and stored for 14 days, compared with untreated samples or samples coated with chitosan and procyanidin. Our study shows the potential of mild PEF treatments combined with OD, or the use of edible coating, to obtain shelf-stable products without substantially affecting the composition or the stability of anthocyanins during digestion in the upper gastrointestinal tract

Thick Co-based coating on cast iron by side laser cladding:Analysis of processing conditions and coating properties

The objective of this work was to create Co-based coatings (compositionally close to Stellite 6) on compacted graphite and gray cast iron,substrates with a high power laser (2 kW continuous Nd:YAG) cladding process. The relationships between the relevant laser cladding parameters (i.e. laser beam scanning speed, laser power and powder feeding rate) and the main geometrical characteristics of a single laser track (height, width, dilution, etc.) were examined. A gradual variation of a single processing parameter was used for an appropriate experimental analysis and statistical correlations study between main processing parameters and geometrical characteristics of an individual laser track. These relations lead to the design of a laser cladding processing map that can be used as a guideline for the selection and further tuning of proper processing parameters for laser cladding of extensive layer. The coatings with thickness from 1.0 to 3.3 mm were created on flat substrates without cracks and other major defects. The nucrostructural features of these coatings were studied using optical microscopy, scanning electron microscopy (Philips XL30 FEG), EDS (EDAX) and XRD. Mechanical properties were determined using microhardness measurement, scratch test (CSM Revetest) analysis at room temperature and using the tribotesting (CSM HT Tribometer) at room and elevated (up to 525 degrees C) temperatures. (c) 2006 Elsevier B.V. All rights reserved

Reconstructing the Density of States by History-Dependent Metadynamics

We present a novel method for the calculation of the energy density of states D(E) for systems described by classical statistical mechanics. The method builds on an extension of a recently proposed strategy that allows the free energy profile of a canonical system to be recovered within a pre-assigned accuracy,[A. Laio and M. Parrinello, PNAS 2002]. The method allows a good control over the error on the recovered system entropy. This fact is exploited to obtain D(E) more efficiently by combining measurements at different temperatures. The accuracy and efficiency of the method are tested for the two-dimensional Ising model (up to size 50x50) by comparison with both exact results and previous studies. This method is a general one and should be applicable to more realistic model systems

Broad histogram relation for the bond number and its applications

We discuss Monte Carlo methods based on the cluster (graph) representation for spin models. We derive a rigorous broad histogram relation (BHR) for the bond number; a counterpart for the energy was derived by Oliveira previously. A Monte Carlo dynamics based on the number of potential moves for the bond number is proposed. We show the efficiency of the BHR for the bond number in calculating the density of states and other physical quantities.Comment: 7 pages, 7 figure