Maintenance of mixed grass-legume pastures for stand longevity and improved animal utilization is a challenge in warm-season climates. The goal of this study was to assess grazing management on stand persistence, forage intake, and N balance of beef heifers grazing mixed pastures of Brachiaria brizantha and Arachis pintoi. A two-year experiment was carried out in Brazil, where four grazing management were assessed: rest period interrupted at 90%, 95%, and 100% of light interception (LI) and a fixed rest period of 42 days (90LI, 95LI, 100LI, and 42D, respectively). The LI were taken at 50 points at ground level and at five points above the canopy for each paddock using a canopy analyzer. For all treatments, the post-grazing stubble height was 15 cm. Botanical composition and canopy structure characteristics such as canopy height, forage mass, and vertical distribution of the morphological composition were evaluated pre-and post-grazing. Forage chemical composition, intake, and microbial synthesis were also determined. A randomized complete block design was used, considering the season of the year as a repeated measure over time. Grazing management and season were considered fixed, while block and year were considered random effects. In the summer, legume mass accounted for 19% of the canopy at 100LI, which was less than other treatments (a mean of 30%). The 100LI treatment had a greater grass stem mass compared with other treatments. In terms of vertical distribution for 100LI, 38.6% of the stem mass was above the stubble height, greater than the 5.7% for other treatments. The canopy structure limited neutral detergent fiber intake (P = 0.007) at 100LI (1.02% of BW/d), whereas 42D, 90LI, and 95LI treatments had NDF intake close to 1.2% of BW/d. The intake of digestible organic matter (OM; P = 0.007) and the ratio of crude protein/digestible OM (P < 0.001) were less at 100LI in relation to the other treatments. The production of microbial N (P < 0.001) and efficiency of microbial synthesis (P = 0.023) were greater at 95LI and 90LI, followed by 42D and less at 100LI. Overall, the range from 90 to 95% of LI is the recommendation to interrupt the rest period, since this strategy enhanced community stability, forage intake, and nutritional value of the diet. Under on-farm conditions, brachiaria grass and forage peanut pastures should be managed at a range height of 24 to 30 cm.

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A methodology for measuring deformations using the PIV technique is proposed. The PIV technique uses a comparison between two images to calculate the displacement. The use of the PIV technique allows obtaining a deformation map of the material surface.

Problemas relacionados à durabilidade da madeira são comumente encontrados em estruturas de edificações históricas. Medidas de preservação e conservação devem ser adotadas, a fim de se evitar perdas e substituições que descaracterizam as construções. Métodos não destrutivos para a detecção de deteriorações podem ser utilizados, a fim de embasar decisões e aumentar a longevidade do patrimônio histórico. Nesse contexto, este trabalho foi realizado com o objetivo de realizar ensaios não destrutivos para inferir sobre a integridade de uma viga e um pilar originais da construção do Sobrado Ramalho, edifício histórico de Tiradentes, MG. Foram utilizados os equipamentos stress wave timer e resistógrafo. Amostras das peças foram retiradas para análises de densidade. Os resultados mostraram que, em ambas as estruturas, para cálculo dos módulos de elasticidade dinâmicos, não houve diferença significativa na aplicação do stress wave timer nos alinhamentos estudados. Não houve diferença significativa entre as direções de aplicação do resistógrafo no pilar, por ele ser aparentemente íntegro, de seções regulares, praticamente quadradas, e por não sofrer carregamento excêntrico. Já na viga houve diferença significativa, supostamente pelo fato de ela possuir trincas na sua linha de tração. Os equipamentos, pouco conhecidos no meio técnico conservacionista de patrimônio, permitem metodologias promissoras para inspeção de estruturas de madeira em serviço.

Adobe is an efficient construction material for several reasons, such as its thermal comfort, sustainability, and lower energy cost, as well as the simplicity of its production and execution. However, challenges such as water absorption, capillarity, and compressive strength should be investigated to improve its physical and mechanical properties. "Synthetic termite saliva" (STS) is an excellent stabilizer with high cohesive and hydrophobic power. Therefore, the objective of this work was to evaluate the effects of STS incorporation into adobe, analyzing its physical, mechanical and thermal properties. Five treatments were studied: 0 (control); 0.1; 0.2; 0.4 and 0.8% STS by mass. These adobe samples were evaluated according to bulk density, linear shrinkage, capillarity, water absorption, thermal conductivity and compressive strength, according to Norma Técnica de Edificación (NTE) E0.80 testing using a new methodology. Linear shrinkage decreases from 2.7 to 1.91 cm with 0.4% STS. Capillarity decreases with the increasing amounts of STS. Water absorption decreased from 12.03 to 6.31% using 0.4% STS, and its mass was reduced from 779 to 19 grams. The thermal conductivity showed no differences between concentrations. The compressive strength was reduced but was still acceptable based on NTE E.080. The stabilization of the adobe using STS showed an improvement in its physical properties, mainly due to its hydrophobic power.