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A técnica in situ é considerada padrão para avaliação da degradação do alimento em dietas de animais ruminantes, permitindo contato direto do alimento com o ambiente ruminal. Objetivou-se avaliar a degradabilidade in situ da matéria seca (MS) e da fibra em detergente neutro (FDN) da lâmina foliar do capim Mombaça submetido a doses crescentes de adubação nitrogenada, 0; 150 e 300 kg de N/ha. As amostras das folhas do capim mombaça foram moídas a 2 mm e, posteriormente, incubadas no rúmen de dois bovinos machos adultos por 0; 4; 8; 12; 24; 48; 72 e 96 horas. Mensurou-se a degradabilidade potencial e degradabilidade efetiva a taxa de passagem a 2%; 4%; 6% sobre a degradabilidade MS e da FDN. A degradabilidade potencial da MS e da FDN foi maior nos tratamentos que receberam adubação nitrogenada (300 e 150 kg de N), assim como a degradabilidade efetiva às 96 horas de incubação. As curvas de degradação da MS e FDN foram paralelas entre si independetemente do tratamento. A adubação nitrogenada aumenta a degradabilidade da MS e da FDN da lâmina foliar do capim mombaça e adubações com 150 ou 300 kg de N ha-1 permitem níveis de degradação semelhantes da MS e FDN.

portuguesPartindo do pressuposto que a formacao das identidades docentes tem inicio na vida escolar, este artigo apresenta uma discussao sobre a producao de memoriais de vida escolar realizada com estudantes de Licenciatura em Ciencias Biologicas, o monitor da disciplinae sua professora. Os relatos foram hibridizados e reorganizados em tres textos, denominados “mosaicos de docencia”. O artigo traz impressoes sobre a escrita e o compartilhamento coletivo dos memoriais e de objetos significativos da vida escolar, bemcomo sobre o primeiro contato dos alunos e alunas com a escola de estagio. Conclui-se, com base em referenciais do campo da pesquisa biografica, que memoriais da vida escolar sao ferramentas potentes para pensar sobre os sentidos da escola e para o deslocamento de certezas e estereotipos sobre docencia, escola e conhecimento, como fios que guiam as nossas identidades docentes. EnglishBased on the assumption that the formation of teacher identities begins in school life, this article presents a discussion about the production of school life memorials held with undergraduate students in Biological Sciences, the monitor of the disciplineand its teacher. The reports were hybridized and reorganized into three texts, called "teachingmosaics". The article brings impressions on the writing and collective sharing of memorials and significant objects of school life, as well as on the students' first contact with the internship school. Based on references from the field of biographical research, it is concluded that memorials of school life are powerful tools for thinking about the meanings of the school and for the displacement of certainties and stereotypes about teaching, school and knowledge as threads that guide our educational identities

Improving beef cattle production in pasture-based systems without expanding agricultural land has been the focus of several studies over the last decades. Nitrogen fertilization is one of the available strategies with high potential to optimize cattle performance in tropical systems. This study aimed to evaluate the effects of increasing nitrogen levels (150, 300, and 450 kg ha−1 of N year−1) in Megathyrsus maximus cv. Mombasa in the humid tropics of the Amazon. The following parameters were evaluated: pasture agronomic characteristics, herbage chemical composition, and beef cattle performance. A total of 24 nine-month-old Nellore bulls with initial mean weight of 173 ± 1.95 kg were used for the performance test. The experimental design was a randomized block with three treatments. Herbage mass and leaf mass contents were increased by the highest nitrogen level (P

Hydrocarbon recovery from subsurface reservoirs imposes physical and chemical property changes for both rock-fluid systems when compared to the initial reservoir conditions. These variations depend on intrinsic and extrinsic factors regarding, on the reservoir side, such as effective stress, fluid type, gravity and saturations, porosity, permeability together with the characteristics of the injected fluids and injection pressure, among others. This study carried out a geomechanical modeling to evaluate the oil production related effects in the Marimba Field, a turbidite sandstone oil bearing reservoir located in the Campos Basin, southeastern offshore Brazil. The applied methodology to solve the proposed problem involves six main stages. It is important to note, when creating a geomechanical model, the finite difference mesh used in the fluid flow simulation and the finite element mesh used for the stress analysis, are not coincident. That is, the pore pressure variation is interpolated to nodal points in the geomechanical mesh. This mesh was generated by using a preprocessor that creates complex geometries, such as those commonly found in turbidite sandstone reservoirs, and was populated with strength and elastic properties by the interpolation of the well logs and laboratory tests information. As an initial field work, the one-way coupling approach was used, enabling the geomechanical effects caused by the Marimba reservoir production to be quantified. However, compaction and permoporous property updates, in the flow simulator, do not occur. Following the geomechanical model initialization and validation, a hydromechanical coupling phase is implemented, ensuing previously determined time steps. At each time step, the simulation proceeds only if the solution converges, that is, if the difference in pore pressure between two iterations is less than the specified tolerance. Finally, the geomechanical model is analyzed for its effects, mainly those related to displacement and compaction. These changes measure the production process impact on the reservoir and on the adjacent rocks. The critical part of this study is to link these quantified changes against reservoir parameter updates, such as pore-pressure and saturation. From the obtained results, areas of greater strain associated with depletion were observed, suggesting porosity reduction mainly near production wells. With this knowledge, it is possible to optimize reservoir oil production and field management.

The objective of the present study was to evaluate the effect of the use of babassu mesocarp meal (BMM) and corn in different physical forms on the feeding behavior of crossbred young bulls of a dairy breed. Twenty-four crossbred (Nellore vs. Holstein) steers (307.35 kg) were fed four experimental diets containing two levels of inclusion of the babassu mesocarp meal (0 and 412.4 g/kg) and corn in two physical forms (kernels or ground) for 98 days. Data was collected on three days during the finishing phase, with observations every five minutes, for 24 hours. When the activities performed by the animals were evaluated as a function of the period of the day, the physical form of the corn showed interaction with the BMM inclusion level on the time spent feeding and on other activities. When the activities were evaluated over the day, the defecation frequency was affected and decreased as BMM was included. The feeding time was longer at the moments that followed feed supply, whereas the time used for other activities increased during the morning period, regardless of the diet utilized. Rumination and idle times were affected by the period of the day and remained high during the night and morning periods. There was increase in feeding time and dry matter rumination efficiencies and neutral detergent fiber as BMM was added to the diet. The number of rumination chews per bolus, however, decreased as BMB was included. Inclusion of babassu mesocarp meal increases the animal feeding time but the physical form of corn does not change its feeding behavior.

Nutrient intake and digestibility and productive performance of 30 feedlot young bulls fed diets containing babassu mesocarp bran in replacement of corn were evaluated. Animals were distributed in a completely randomized design with five levels of replacement of corn by babassu mesocarp bran (BMB): 0, 250, 500, 750 and 1000 g/kg of dry matter, and six replications. The dry matter (DM) intake in kg/day, g/kg body weight (BW) and g/kgBW0.75 increased as the corn was replaced by BMB. The intake of neutral detergent fiber (NDF) and crude protein (CP) increased linearly, whereas the intake of non-fibrous carbohydrates (NFC) had quadratic behavior. The digestibility of DM, CP, NDF and NFC and the total digestible nutrients (TDN) showed quadratic behavior with points of minimum digestibility of 850.0, 638.0, 867.0, 638.0 and 833.0 g/kg dry matter of replacement of corn by BMB, respectively. The final weight (476.82 kg) and average daily gain (1.55 kg/day) were not affected by experimental diets. The feed efficiencies of DM and CP decreased with increase in the levels of BMB, but the feed efficiency of TDN was not changed. Babassu mesocarp bran enables satisfactory performance, and depending on the price and opportunity cost, it can be utilized in the feeding of feedlot cattle totally replacing the corn of the diet.