Temperatura superficial de bovinos considerando áreas com e sem a presença de pelos.

Nos últimos anos um grande número de estudos utilizando a análise de imagens termográficas de animais na faixa do infravermelho vem sendo realizado. Além dos avanços tecnológicos que tornaram os sensores mais acessíveis, a preocupação com o bem estar e ambiência das instalações animais tem fomentado a utilização desse método não invasivo e de fácil execução. Neste trabalho foram utilizados 20 bovinos das raças Nelore e Pantaneiro. Após tricotomia de uma área sobre o músculo Longissimus dorsi próximo da 13ª costela, seguida de repouso por 24 horas, os animais foram avaliados por três dias consecutivos, seis vezes por dia. Foram aferidas as temperaturas em áreas com e sem pelos com uso de câmera termográfica. O experimento foi realizado em um Delineamento Inteiramente Casualizado (DIC), considerando o efeito de raça. As variáveis temperatura sem pelo (TSP) e a diferença de temperatura entre áreas com e sem pelo (DIF) não apresentaram efeito significativo para raça. Por outro lado, para a temperatura em áreas com pelos(TCP) o efeito de raça foi significativo, com os pantaneiros apresentando as maiores médias. Animais de ambas as raças encontravam-se em condições de conforto térmico durante o experimento. Os resultados mostram a necessidade de se olhar com cautela para trabalhos envolvendo imagens termográficas capturadas em superfícies recobertas por pelos em animais. Como as avaliações foram feitas na sombra e só houve diferença significativa entre áreas com pelos, é possível que as temperaturas registradas com termografia infra vermelha na superfície da pelagem dos animais representem, pelo menos em parte, características termofísicas dos pelos que as compõem (como a capacidade térmica, por exemplo), sendo tais temperaturas pouco representativas para a superfície do corpo dos indivíduos propriamente, como é comum se considerar.

Dinâmica espaço-temporal da temperatura de superfície, da bacia do rio Corumbataí, SP utilizando imagens do sensor TM/Landsat.

Neste estudo foram empregados sistemas de informações geográficas e técnicas de sensoriamento remoto para investigar o efeito do uso e cobertura do solo sobre a temperatura da superfície do solo (TSS) nos anos de 1985, 1990, 1995, 1999, 2002 e 2011, na bacia do Rio Corumbataí (BRC), SP. O padrão espacial da TSS foi derivado de imagens do satélite Landsat, por meio da banda termal do sensor TM. Estudou-se a relação entre os índices NDVI, NDBI, MI e da altitude com a TSS. A TSS da BRC foi crescente até o ano de 1999 e reduziu até o ano de 2011. O padrão espacial da TSS foi influenciado pelo uso e cobertura do solo. Houve correlação negativa da TSS com o NDVI e MI e positiva com o NDBI. Áreas de pastagem e áreas de cana-de-açúcar colhidas podem atingir TSS superiores às áreas urbanas, dependendo das condições de umidade do ambiente. Conclui-se que os dados do TM/Landsat associados aos dados coletados em campo, apresentam potencial para identificação de padrões térmico-hídricos em estudos de bacias hidrográficas.

Otimização das condições de produção de ésteres etílicos a partir de óleo de peixe com elevado teor de ácidos graxos ômega-3

The production of ethyl esters by alcoholysis is an alternative for splitting triacylglycerols due to the possibility of using low temperatures, which results in oxidative protection of the polyunsaturated fatty acids. Ethyl esters produced under mild conditions of temperature could be used as substrate for obtaining structured lipids. The reaction parameters of production of ethyl esters from fish oil with high content of omega-3 fatty acids by alcoholysis were optimized using response surface methodology. An experimental design (2³) (with levels +1 and -1, six axial points with levels -alpha and +alpha and three central points) was applied. The variables investigated were concentration of catalyst, amount of ethyl alcohol and temperature. Ethyl ester conversion was monitored by high performance size exclusion chromatography (HPSEC) and the best result obtained was 95% conversion rate. The optimal conditions were 40 °C, 1% of NaOH and 36% of ethanol.

Efeito das interações hiperconjugativas na constante de acoplamento ¹J CH da hexametilenotetramina e do adamantano: estudo teórico e experimental

The objective of this work was to determine the influence of hyperconjugative interactions on the ¹J CH coupling constant for hexamethylenetetramine (1) and adamantane (2). For this end, theoretical and experimental ¹J CH were obtained and hyperconjugative interactions were investigated using NBO. It was observed, theoretically and experimentally, that ¹J CH in 1 is 20 Hz larger than in 2, mainly due to the nN®s*C-H hyperconjugative interaction. This interaction occurs only in 1, with an energy of 9.30 kcal mol-1. It increases the s-character of the carbon atom in the C-H bond and the occupancy of the sigma*C-H orbital in (1).

Possibilidades e limitações no uso da temperatura em cromatografia líquida de fase reversa

High-temperature liquid chromatography (HTLC) is a technique that presents a series of advantages in liquid phase separations, such as: reduced analysis time, reduced pressure drop, reduced asymmetry factors, modified retentions, controlled selectivities, better efficiencies and improved detectivities, as well as permitting green chromatography. The practical limitations that relate to instrumentation and to stationary phase instability are being resolved and this technique is now ready to be applied for routine determinations.

Uma revisão sobre o efeito Toms: o fenômeno onde macromoléculas atenuam a turbulência em um líquido

It is very well known that the addition of polymers to a liquid increases the shear viscosity of the solution. In other words, the polymer increases the dissipation of the flow energy. Contrarily, in turbulent flow, some particular macromolecules in very low concentration are able to produce large attenuation in the turbulence and thus, decreasing the dissipation of the energy. This article present a brief revision about macroscopic and molecular models used to explain this dynamic effect. Some of the experimental techniques used to quantify the attenuation of the turbulence and the main active substances are also discussed.

Caracterização reológica das diferentes fases de extrato de inulina de raízes de chicória, obtidas por abaixamento de temperatura

Inulin is a functional food ingredient, generally employed as sugar or fat substitute in food systems. This ingredient can be found in several vegetal products, including chicory roots. As the solubility of inulin is susceptible to temperature changes, the product suffers a fractionalization resulting in two phases when cooled, originating a precipitated phase, more viscose, and a liquid phase, of lesser viscosity. The study of rheological properties of different phases of inulin extract is important for equipment designing, such as mixer and bombs. In this work, rheological behavior at three different temperatures (25; 40 and 50 ºC) was determined for liquid and precipitated phases of inulin liquid extract, extracted from chicory roots by hot water diffusion and cooled at two different temperatures (8 and -10 ºC), suffering phases separation. The precipitated phase was analyzed in two conditions: pure and with the addition of microencapsulating agents (maltodextrin and hydrolized starch). All of them presented a linear behavior, similar to that of the Plastics of Bingham. Some of them, however, were not an adequate fit to this model.

Índice de previsão de produção de leite para vacas Jersey

In Brazil the adoption of several models of cattle confinement leads to special conditions for management methods in dairy production, which can be improved by the use of technology that assures better herd management. Indexes relating environmental variables to production are applied for the prediction of milk production. The values of temperature and relative humidity, rain index, solar radiation and pasture soil temperature are generally considered potential stress agents for cows. The objective of this research was to develop an index for predicting milk production for high productivity Jersey milking cows lodged in semi confinement in tropical conditions. The experiment considered two treatments: A - the cows waited for 30 minutes prior to milking in a room with a shower associated to a fan; B - the cows did not have access to this room (control). Other than the waiting period, the cows had access to pasture. Differences in the effect of average production were not statistically significant. The analysis for studying the effect of the variables and designing the model led to a statistical model relating the variables milk production and rain index, as well as the maximum soil temperature of pasture, and milk production.

Influência do processo de secagem na qualidade do cogumelo shiitake

Edible mushroom are highly perishable foods. Drying is an alternative to provide safe storage. In this work, the effects of some drying parameters on the quality of Shiitake mushroom were investigated: geometry of the raw material (whole and sliced), drying temperature (50 °C and 70 ºC) and final moisture content (5% and 15% wb). Experimental kinetics of drying was built and color and texture analyses were done in fresh and in rehydrated dried product. The effect of parameters was evaluated by analysis of variance and test of multiple comparisons. Drying kinetics showed that drying happened in falling-rate period and sliced mushroom dried at 70 ºC required lesser drying time than other treatments. Mushroom dried at 70 ºC showed less darkening. Drying time affected mushroom quality, evaluated by great hardness, gummosis and darkening.

Efeitos da temperatura do ar, linhagem e período do dia nas freqüências de ocorrências e tempos de expressão comportamental de matrizes pesadas

Behavioral adjustments may occur fast and with less cost than the physiological adaptations. Considering the social behavior is suggestive that the frequency and the intensity of aggressive interactions, the total social cohesion and the extent of vicious attitudes may be used to evaluate welfare. This research presents an analysis of the interactions between the experimental factors such as temperature, genetic and time of the day in the behavior of female broiler breeders under controlled environment in a climatic chamber in order to enhance the different reaction of the birds facing distinct environmental conditions. The results showed significant differences between the behaviors expressed by the studied genetics presenting the need of monitoring them in real-time in order to predict their welfare in commercial housing, due to the complexity of the environmental variables that interfere in the well being process. The research also concluded that the welfare evaluation of female broiler breeders needs to consider the time of the day during the observation of the behaviors.

Modelos estatísticos indicadores de comportamentos associados a bem-estar térmico para matrizes pesadas

The study of female broiler breeders is of great importance for the country as poultry production is one of the largest export items, and Brazil is the second largest broiler meat exporter. Animal behavior is known as a response to the effect of several interaction factors among them the environment. In this way the internal housing environment is an element that gives hints regarding to the bird s thermal comfort. Female broiler breeder behavior, expresses in form of specific pattern the bird s health and welfare. This research had the objective of applying predictive statistical models through the use of simulation, presenting animal comfort scenarios facing distinct environmental conditions. The research was developed with data collected in a controlled environment using Hybro - PG® breeding submitted to distinct levels of temperature, three distinct types of standard ration and age. Descriptive and exploratory analysis were proceeded, and afterwards the modeling process using the Generalized Estimation Equation (GEE). The research allowed the development of the thermal comfort indicators by statistical model equations of predicting female broiler breeder behavior under distinct studied scenarios.

Efeito da adição de cinza da casca de arroz em misturas cimento-casca de arroz

The rice husk and its ash are abundant and renewable and can be used to obtain alternative building materials. An increase in the consumption of such waste could help minimize the environmental problems from their improper disposal. This study aimed to evaluate the use of ashes as a cargo mineral (filler). However, the rice husk chemically interferes in the conduct of the based cement mixtures. Thus, different mixes cement-rice husk with and without the addition of ash were evaluated in order to highlight the influence of its components (husk; ash), which could otherwise be excluded or be underestimated. Cylindrical samples (test of simple compression and traction by diametrical compression) and samples extracted from manufactured pressed board (test of bending and parallel compression to the surface), were used to evaluate the behavior of different mixtures of components (rice hush; RHA - rice husk ahs). The results of the mechanical tests showed, in general, there is not a statistical difference between the mixtures, which are associated with the chemical suppressive effect of the rice husk ash. The mixture of rice husk of 10 mm, with an addition of 35% of the rice husk ash, is notable for allowing the highest consumption of rice husk and rice husk ash, to reduce 25% the consumption of cement and to allow the storage (without emissions to the atmosphere), around 1.9 ton of CO2 per ton of cement consumed, thus contributing to the reduction of CO2 emissions, which can stimulate rural constructions under an ecological point of view.

Influência da temperatura do ar de secagem no calor latente de vaporização de água em feijão macassar (Vigna unguiculata (L.) Walp.), variedade sempre-verde

In order to determine the energy needed to artificially dry an agricultural product the latent heat of vaporization of moisture in the product, H, must be known. Generally, the expressions for H reported in the literature are of the form H = h(T)f(M), where h(T) is the latent heat of vaporization of free water, and f(M) is a function of the equilibrium moisture content, M, which is a simplification. In this article, a more general expression for the latent heat of vaporization, namely H = g(M,T), is used to determine H for cowpea, always-green variety. For this purpose, a computer program was developed which automatically fits about 500 functions, with one or two independent variables, imbedded in its library to experimental data. The program uses nonlinear regression, and classifies the best functions according to the least reduced chi-squared. A set of executed statistical tests shows that the generalized expression for H used in this work produces better results of H for cowpea than other equations found in literature.

Avaliação de linhas de beneficiamento e impactos de queda na qualidade de caqui Rama Forte

Excessive and inadequate handling of fruits and vegetables provides high incidences of physical damage, consequently, post harvest losses. The main goal of this work was to evaluate the impact magnitude in persimmon packing lines, Rama Forte, and to determine, at the laboratory, its impact limits. For evaluating the critical points it was used an instrumented sphere of 76 mm of diameter (Technmark, Inc, Lansing, USA), which registered the impact magnitude in seven distinctive impact lines located in four packing houses. For determining physical damages, tests were carried out at the laboratory, where fruit drop was related to impact magnitude, physical damage incidence and fruit post harvest losses. At the packing lines, the values found varied from 21 to 87 G on the transfer points and the majority of registered impacts (over 94%) were down 50G. Drops from 20 cm caused an increase in weight losses after six days of storage at room temperature. Drops from 20 and 30 cm caused skin darkness (low L values), associated to a decrease in color intensity (chroma). Impact drop did not affect pulp fruit chemical features.

Otimização do descascamento químico de raízes do yacon (Polymnia sonchifolia Poepp.)

A full factorial design 2³ was used to evaluate the effect of process variables in chemical peeling of yacon roots, cultivated in Curitiba, State of Paraná. Eleven treatments, with three central points, were done in which they had been evaluated at three different levels of sodium hydroxide solution, % (g/100 mL) [6, 10, 14], temperature of the same solution, °C [70, 80, 90], and residence time in the sodium hydroxide solution, minutes [2, 4, 6]. All the studied variables had affected significantly (p<0.05) the yield of yacon roots subjected to chemical peeling. The variable that most affected the yield was the time of permanence in the sodium hydroxide solution. The mathematical model obtained for the yield (%) was good with R² aj = 0.8497, and non significant lack of fit (p=0.9312).Therefore, the model can be used for predictive purposes. In the central point a satisfactory yield (84% to 87%) with a high percentage of removed peel was obtained (96% to 98%) indicating that the treatment with 10% of sodium hydroxide solution, temperature of 80º C per 4 minutes can be used in the chemical peeling of yacon roots.