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Congonhas, Brazil

Rosa G.M.,Instituto Federal Minas Gerais | da Luz J.A.M.,Federal University of Ouro Preto
Revista Escola de Minas | Year: 2011

The behavior of batch grinding of a dry binary mix using dolomite and quartz has been studied. Through several tests with different proportions of these minerals and different grinding cycles, the granular system evolution was observed in terms of sharpness coefficient and mean diameter d50. These parameters were fit into the Hill's sigmoidal function of probability distribution to adjust the results. The results were used for the validation of a neural network system (multilayer perceptron-like algorithm), which will be presented in another article.

Evangelista W.L.,Instituto Federal Minas Gerais | De Fatima Tinoco I.,Federal University of Vicosa | De Souza A.P.,Federal University of Vicosa | Minette L.J.,Federal University of Vicosa | And 3 more authors.
Work | Year: 2012

Companies have increasingly sought strategies that will ensure a more competitive position in the marketplace. Among these strategies adopted by companies include the health and welfare of the worker, factors currently valued by consumers, especially those of most demanding market. Thus, the postural analysis is of great importance and interest because it is the study of positioning related to body parts like head, torso and limbs, capable of producing loads that may be excessive or insufficient causing disturbances in the muscle skeletal system worker. The aim of this study was to perform a postural analysis of the main sectors of workers (slaughter, cutting room, special cuts, packaging and dispatch) of a typical refrigerator pig industry in Brazil during the execution of their daily activities as well as developing proposals to minimize and/or eliminate the diseases and accidents. The study followed the safety norms of Brazilian Ministry of Labor and Employment. The posture analysis used the OWAS (Ovako Working Posture Analyzing System) methodology. The postures assumed by workers in the sector of packaging were as the most in need of emergency and quick action. © 2012 - IOS Press and the authors. All rights reserved.

Sales J.F.,Federal University of Goais | Pinto J.E.B.P.,Federal University of Lavras | de Oliveira J.A.,Federal University of Lavras | Botrel P.P.,Federal University of Lavras | And 2 more authors.
Acta Scientiarum - Agronomy | Year: 2011

This study evaluated the effect of light, temperature, physiologic stage at harvest and length of time on the germination of Hyptis marrubioides seeds. Two trials were conducted. The first experiment was performed immediately after the seed harvest and consisted of a 2 x 3 x 3 factorial design with 2 environmental conditions (light and dark), 3 temperatures (20, 30 and 20/30°C) and 3 seed harvest times (green colored seeds, light brown seeds and dark brown seeds). The second experiment was conducted in the presence of light at a temperature of 30°C and consisted of a 4 x 3 factorial design, with 4 storage times (0, 6, 12 and 18 months) and the 3 three harvest physiologic stages used in the previous experiment. Both of the experiments were conducted in randomized blocks, with 4 replications of 100 seeds. Light did not affect germination. By contrast, a temperature of 20°C retarded the germination process, although the percentage of germinating seeds was not affected. Seed storage and the different harvest physiologic stages affected the Speed of germination index (SGI) and the germination percentage. Seeds that were harvested at the more mature stage (dark brown color) could be stored for up to 18 months.

Teixeira B.B.,Federal University of Vicosa | Euclydes R.F.,Federal University of Vicosa | Teixeira R.B.,Instituto Federal Minas Gerais | da Silva L.P.,Federal University of Vicosa | And 4 more authors.
Ciencia Rural | Year: 2013

The objective of this study to determine the heritability of characteristics of productive and reproductive performance of different genetic groups of arrays of meat quails, estimating genetic parameters using univariate analyzes. We evaluated two genetic groups (UFV1 and UFV2) in the period 2006 to 2009, being accompanied by five generations, totaling 2136 arrays. Quail were weighed at birth, 7, 14, 21, 28, 35, 42, 77, 112 and 147 days of age. We evaluated each quail eggs were collected for three consecutive days, during four periods of 35 days and measured the width and length of eggs, yolk weight, albumen and shell. We evaluated the specific gravity of eggs and measured the rate of overall posture and age at first egg. Univariate analyzes were performed to estimate the variance components, using the method of restricted maximum likelihood using the program and calculated the MTDFREML hedabilidades. For the quality of eggs heritability values were moderate to high (0.13 to 0.55), high values for growth (0.64 to 0.68) and moderate to high for egg shape (0.10 to 0.57). Heritability estimates for egg quality found indicate a high genetic variability for both genetic groups. As for the weights indicated that selection within the population could result in increases in weight by selection based on individual information. For the characteristics of an egg shape, the heritability values suggest the possibility of genetic groups that meet a standard shape.

Moretti B.S.,Federal University of Lavras | Neto A.E.F.,Federal University of Lavras | Pinto S.I.C.,Instituto Federal Minas Gerais | Furtini I.V.,Federal University of Lavras | Magalhaes C.A.S.,Embrapa Roraima
Cerne | Year: 2011

In order to evaluate nutritional requirements and the effect of nutrient deprivation on the development of seedlings of Australian cedar (Toona ciliata M. Roem var. australis), a greenhouse experiment was conducted. The substrate used was a dystroferric red latosol with low nutrient availability, using 15 treatments and applying the missing element technique. The experiment included two complete treatments (one provided N, P, K, S, B, Cu, Zn with limestone while another provided N, P, K, Ca, Mg, S, B, Cu and Zn without limestone), besides deprivation of each nutrient (-N, -P, -K, -Ca, -Mg, -S, -B, -Cu and -Zn), one treatment with combined deprivation of B, Cu and Zn, one treatment applying limestone only, one treatment applying N, P, K, S, B, Cu and Zn, without limestone, and one absolute control treatment (natural soil). The following characteristics were evaluated: height, diameter, shoot dry matter and root dry matter, and nutrient content in the shoot dry matter after 150 days. Australian cedar plants have high nutritional requirements, and nutrients P, N, S, Ca, K, Mg and Cu, in that order, were found to be limiting factors to plant development. B and Zn deprivation did not affect plant development. Limestone application was essential for the development of Australian cedar plants. Initial deficiency symptoms were found to be the result of S, limestone and N deprivation.

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