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Based on the necessity for enclosure protection of temperature and relative humidity sensors installed in a hostile environment, a wind tunnel was used to quantify the time that the sensors take to reach equilibrium in the environmental conditions to which they are exposed. Two treatments were used: (1) sensors with polyvinyl chloride (PVC) enclosure protection, and (2) sensors with no enclosure protection. The primary objective of this study was to develop and validate a 3-D computational fluid dynamics (CFD) model for analyzing the temperature and relative humidity distribution in a wind tunnel using sensors with PVC enclosure protection and sensors with no enclosure protection. A CFD simulation model was developed to describe the temperature distribution and the physics of mass transfer related to the airflow relative humidity. The first results demonstrate the applicability of the simulation. For verification, a sensor device was successfully assembled and tested in an environment that was optimized to ensure fast change conditions. The quantification setup presented in this paper is thus considered to be adequate for testing different materials and morphologies for enclosure protection. The results show that the boundary layer flow regime has a significant impact on the heat flux distribution. The results indicate that the CFD technique is a powerful tool which provides a detailed description of the flow and temperature fields as well as the time that the relative humidity takes to reach equilibrium with the environment in which the sensors are inserted. [ABSTRACT FROM AUTHOR]

Abstract: Liver steatosis was once believed to be a benign condition, with rare progression to chronic liver disease. Thus, in both clinical and experimental practice, it is fundamental to have a reliable and objective method for its precise quantification. An image analysis algorithm was developed and validated for automatically and rapidly quantifying hepatic fat microvesicles. The image processing algorithms automatically segmented interstitial steatosis areas and analyzed the threshold region. Automatic quantifications did not significantly differ from manual evaluations of means of the same areas. Comparison of our image analysis quantifications with staging of histologic evaluations of liver steatosis presented significant correlations that are based on the distribution patterns and on the area quantity of steatosis, respectively. The use of algorithms for analysis and image processing is a sensitive, precise, objective and reproducible method of quantifying hepatic fat microvesicles, which complements semi-quantitative histologic evaluation systems. [Copyright &y& Elsevier]

The objective of this work was to study the main effects of rain water spray stored on steel tiled roof of commercial facilities for the production of broilers, in the center-west region of Brazil. Climatic variables, temperature of the under surface of the tiles, zootechnical indexes, thermal comfort indexes were evaluated. Additionally, operating time, water and energy consumption by the cooling system were evaluated. The experimental design was completely randomized with two treatments and three repetitions: Treatment 1 - three steel tiled roof broiler sheds equipped with internal cooling system, tunnel with negative pressure mode, and a sprinkling of rainwater system (SR); Treatment 2 - three broiler sheds identical to the treatment 1, however without a sprinkling of rainwater system (WSR). The SR treatment reduced 19.5 °C average temperature of the under surface of the tiles in the most critical time of day, which was at 3:00 pm and the environmental average temperature in the same position of the animals was reduced about 1.9 °C. Moreover, the thermal indexes showed lower values throughout the experimental period in the SR treatment. In addition, operating time of the second and third extractor group were reduced 4.8%, and 7.5% respectively; while internal misting pump had 9,6% of operating time reduced. This allowed reducing of electricity consumption, mortality reduction, improvement in feed conversion and increased average slaughter body mass gain. [ABSTRACT FROM AUTHOR]