Avaliação do desempenho produtivo de bovinos de corte, em pastos puros e consorciados com o amendoim forrageiro cultivar Mandobi, no Acre.

Objetivou-se avaliar o efeito da consorciação de pastos de Brachiaria humidicola com Arachis pintoi cv. Mandobi sobre o desempenho produtivo de novilhos Nelore. O experimento foi realizado em uma fazenda particular no Estado do Acre, de novembro de 2013 a fevereiro de 2014. As unidades experimentais foram seis piquetes de 1,42 ha cada, em um delineamento inteiramente casualizado, com dois tratamentos e três repetições. Foram utilizados seis novilhos Nelore, não castrados, com idade e peso médio iniciais de 16 meses e 282 kg, como testes. Novilhos adicionais foram alocados ou retirados dos piquetes para a manutenção da altura do pasto, em 15 cm. Os animais foram pesados a cada 28 dias, após um jejum de 16 horas, para determinar o ganho de peso médio diário (GMD). A capacidade de suporte foi calculada de acordo com o peso médio e número de animais/dia em cada unidade experimental. A produtividade animal foi calculada com base no GMD dos animais teste e o número de animais/dia utilizados durante todo experimento. As médias dos quadrados mínimos foram comparadas usando o teste de Tukey com 5% de probabilidade. A taxa de lotação durante o período experimental foi de 3,97 UA/ha nos pastos consorciado e 3,81 nos pastos puros (P = 0,8255). O ganho de peso médio diário dos animais foi 17,7% superior (P = 0,0465) para o pasto consorciado (0,597 x 0,479 kg/animal/dia) e a produtividade animal aumentou 18,7% (P = 0,1010) pelo uso de A. pintoi cv. Mandobi (330 kg/ha x 278 kg/ha). Este estudo mostra que apenas 7,7% desta leguminosa em pastagens consorciadas com Brachiaria humidicola pode afetar positivamente a produtividade animal

Using a glass-fibre reinforced polymer composite in the production of sustainable water storage vessels

The quest for sustainability by rethinking materials, products and production strategies is an enormous challenge currently laid upon the economic sector. Materials selection plays a critical role in this challenge. The present work describes a technological, environmental and economic study of the production of a water storage glass-fibre reinforced composite vessel. The vessel was evaluated via a Life Cycle Assessment/Life Cycle Costing (LCA/LCC) integrated model. The most significant life cycle phase was found to be the raw materials production, in which the Fossil fuels, Respiratory inorganics and Climate change were the relevant impact categories. The vessel environmental and economic performances could be improved if an end of life (EoL) option different from landfill had been chosen. The present work describes a new integrated way of analysing the environmental and economic performances of a structural product full life cycle. It also highlights the role and importance of fibre reinforced polymer composites in the quest for sustainable products.FCT projeto SFRH/BD/60852/2009 e IPC projeto UID/CTM/50025/201

Invasion Percolation Between two Sites

We investigate the process of invasion percolation between two sites (injection and extraction sites) separated by a distance r in two-dimensional lattices of size L. Our results for the non-trapping invasion percolation model indicate that the statistics of the mass of invaded clusters is significantly dependent on the local occupation probability (pressure) Pe at the extraction site. For Pe=0, we show that the mass distribution of invaded clusters P(M) follows a power-law P(M) ~ M^{-\alpha} for intermediate values of the mass M, with an exponent \alpha=1.39. When the local pressure is set to Pe=Pc, where Pc corresponds to the site percolation threshold of the lattice topology, the distribution P(M) still displays a scaling region, but with an exponent \alpha=1.02. This last behavior is consistent with previous results for the cluster statistics in standard percolation. In spite of these discrepancies, the results of our simulations indicate that the fractal dimension of the invaded cluster does not depends significantly on the local pressure Pe and it is consistent with the fractal dimension values reported for standard invasion percolation. Finally, we perform extensive numerical simulations to determine the effect of the lattice borders on the statistics of the invaded clusters and also to characterize the self-organized critical behavior of the invasion percolation process.Comment: 7 pages, 11 figures, submited for PR

Association between genomic daughter pregnancy rate and expected milk production on the resumption of estrus behavior in Holstein cattle

The objective of this observational study was to evaluate estrous expression at the first estrus occurring between 7 to 30 d in milk (DIM), as detected by an automated activity monitor (AAM), and its association with genomic daughter pregnancy rate (GDPR) and genomic expected milk production (GEM) in lactating dairy cows. A total of 4,119 lactations from 2,602 Holstein cows were included. Cows were enrolled as first lactation (n = 1,168), second lactation (n = 1,525) and third and greater lactation (n = 1,426). Hair samples were collected from the tail switch, and cows were genotyped using an SNP platform (Clarifide, Zoetis, São Paulo, SP, Brazil). Postpartum cows were examined daily by the farm personnel from calving until 10 DIM. Calving was classified as assisted (forced calf extraction) and unassisted (normal calving). Retained fetal membranes (RFM), hyperketonemia (KET), and left displaced abomasum (LDA) were also recorded. Mean GDPR (± SD) was −0.29 ± 1.4, and the intensity and duration of the first estrus event was 15.9 ± 13.1 x-factor (intensity unit measurement) and 11.1 ± 3.8 h, respectively. Cows that had greater GDPR had greater intensity and longer duration of estrus at the alert, independent of parity. Overall resumption of estrous expression, between 7 to 30 DIM, was 41.2% (1,695/4,119), where 58.8% (2,424/4,119) did not have an estrus event, 31.0% (1,274/4,119) of cows had one event of estrus, and 10.2% (421/4,119) of cows had 2 or more events of estrus early postpartum. Mean DIM (± SD) at first estrus event, detected by the AAM, was 19.4 ± 4.4 d. Days in milk at first event for cows with one event was 20.7 ± 1.6 d and 15.9 ± 3.1 d for cows with 2 or more events of estrus. First lactation cows were more likely to have an estrus event early postpartum when compared with second and third and greater lactation cows (45.2 ± 1.4% [530/1168] vs. 41.6 ± 1.3% [636/1525] vs. 37.2 ± 1.3% [529/1426], respectively). There was an interaction of parity and GDPR on the proportion of cows demonstrating an early postpartum estrus. There was no difference in the proportion of cows with an early postpartum estrus between those with assisted or unassisted calving, RFM, or LDA. However, cows that had KET were less likely to have an alert early postpartum when compared with cows that did not have KET. Mean genomic expected milk production (± SD) was 256.8 ± 600.1 kg. There was no interaction between GEM and parity on estrous expression (i.e., intensity and duration). There was no interaction between GEM and GDPR on the proportion of estrus early postpartum

Combinatorial analysis of marine based biomaterials: high-throughput analysis of the effect of nanostructured multilayers on cell behaviour

Publicado em "Journal of Tissue Engineering and Regenerative Medicine", vol. 7, supp. 1 (2013)In a marine environment, specific proteins are secreted by mussels and used as a bioglue to stick to a surface allowing generate irreversible bonding. Adhesive secreted proteins of mussels present an unusual amino acid 3,4-dihydroxyphenylalanine (DOPA). Inspired by the struc- ture and properties of mussel adhesive proteins, layer-by-layer (LbL) coatings based on polymers that contain catechol groups were devel- oped. We used dopamine-modified hyaluronic acid (HA-DN) prepared by carbodiimide chemistry to form thin and surface-adherent dopamine films. The multilayer films were developed by electrostatic interactions using chitosan (CHT) as polycation and HA-DN as polyanion. Multilay- ers films of CHT and HA were used as control. The formation of these films was investigated in-situ by quartz crystal microbalance with dissi- pation monitoring (QCM-D). Afterwards, many combinations of the marine inspired biomaterials were analysed in a high-throughput (HTS) way. Such multilayers were constructed and individually dis- posed on isolated transparent spots, patterned onto biomimetic super- hydrophobic substrates. The adhesion properties of the coatings in the chips were also analyzed. In vitro tests using two distinct cell sources were carried out to evaluate the biological performance of the different combinations of multilayers that could be useful in different biomedical applications, including tissue engineering