The protoMIRAX Hard X-ray Imaging Balloon Experiment

The protoMIRAX hard X-ray imaging telescope is a balloon-borne experiment developed as a pathfinder for the MIRAX satellite mission. The experiment consists essentially in a coded-aperture hard X-ray (30-200 keV) imager with a square array (13$\times$13) of 2mm-thick planar CZT detectors with a total area of 169 cm$^2$. The total, fully-coded field-of-view is $21^{\circ}\times 21^{\circ}$ and the angular resolution is 1$^{\circ}$43'. In this paper we describe the protoMIRAX instrument and all the subsystems of its balloon gondola, and we show simulated results of the instrument performance. The main objective of protoMIRAX is to carry out imaging spectroscopy of selected bright sources to demonstrate the performance of a prototype of the MIRAX hard X-ray imager. Detailed background and imaging simulations have been performed for protoMIRAX balloon flights. The 3$\sigma$ sensitivity for the 30-200 keV range is ~1.9 $\times$ 10$^{-5}$ photons cm$^{-2}$ s$^{-1}$ for an integration time of 8 hs at an atmospheric depth of 2.7 g cm$^{-2}$ and an average zenith angle of 30$^{\circ}$. We have developed an attitude control system for the balloon gondola and new data handling and ground systems that also include prototypes for the MIRAX satellite. We present the results of Monte Carlo simulations of the camera response at balloon altitudes, showing the expected background level and the detailed sensitivity of protoMIRAX. We also present the results of imaging simulations of the Crab region. The results show that protoMIRAX is capable of making spectral and imaging observations of bright hard X-ray source fields. Furthermore, the balloon observations will carry out very important tests and demonstrations of MIRAX hardware and software in a near space environment.Comment: 9 pages, 13 figures, accepted for publication in Astronomy & Astrophysic

Efeito da inclusão de diferentes tipos de óleo na dieta de varrões sobre a qualidade do sêmen "in natura" Effect of the inclusion of different types of oil in the diet of boars on the quality of semen "in natura"

O experimento foi realizado no Departamento de Zootecnia da Universidade Federal de Lavras-MG, com o objetivo de avaliar o desempenho reprodutivo de varrões alimentados com rações suplementadas com diferentes tipos de óleos como fontes de ácidos graxos essenciais. Foram utilizados 24 suínos híbridos (AGPIC 337), machos inteiros, com peso inicial médio de 152,7 kg, em um delineamento experimental em blocos ao acaso, com quatro tratamentos (T1 = controle; T2 = 3% óleo de linhaça; T3 = 3% óleo comercial PUFA® e T4 = 3% de óleo de peixe) e seis repetições, com um animal por unidade experimental. As rações foram isoenergéticas e isoprotéicas, formuladas à base de milho e farelo de soja. As variáveis analisadas foram parâmetros seminais como motilidade, vigor, volume, concentração, número total de células e anomalias espermáticas, avaliadas entre a quarta e a décima primeira semana do início do fornecimento das rações aos animais. Não houve diferenças significativas entre os tratamentos para motilidade, concentração e anormalidades espermáticas totais (P>0,05), exceto para alteração de cauda (P<0,05), cuja suplementação com óleo de peixe apresentou pior resultado. Por outro lado, o vigor espermático foi significativamente maior para o óleo de peixe (P<0,05). Para volume e número total de espermatozóides no ejaculado, melhores resultados foram obtidos com o óleo comercial PUFA® (P<0,05). Conclui-se que, nas avaliações do sêmen in natura, o uso de óleo comercial PUFA® e óleo de peixe nas rações de varrões demonstrou ser mais eficiente para a produção de células espermáticas e para a viabilidade destas células, respectivamente.<br>The experiment was conducted at Animal Science Department of University of Lavras-MG, with the objective to evaluate the quality of semem in natura of boars fed with rations supplemented with different sources of oils as sources of essential fat acids. Twenty four hybrid boars (AGPIC 337) were used, with initial average weight of 152,7 kg, assigned into a randomized complete blocks design, with four treatments (T1 = control; T2 = 3% linseed oil; T3 = 3% commercial oil PUFA® and T4 = 3% of fish oil) and six repetitions, being each animal as a experimental unit. The diets were isoenergetics and isoproteics, formulated with corn and soybean meal. The analyzed variables were seminal parameters as mobility, vigor, volume, concentration, total number of cells and anomalies spermatic, valued between four and eleventh week of the experimental period. The data showed any significant differences among the treatments for the motility, concentration and total anomalies spermatic (P>0,05), except for alteration of tail (P<0,05), whose supplementation with fish oil shown worse results. Also the spermatic vigor were significantly higher (P<0.05) for the boars fed rations with fish oil suplementation. The volume and total number of spermatozoid in the ejaculate, showed best results for those boars fed rations with commercial oil PUFA® (P<0,05). It was conclude that, the quality of the semen in natura, for boars fed rations he supplemented with commercial oil PUFA® and the fish oil showed to be more efficient for the parameters spermatic cells production and cells viability in the young boars