Spillover and diffraction sidelobe contamination in a double-shielded experiment for mapping Galactic synchrotron emission

We have analyzed observations from a radioastronomical experiment to survey the sky at decimetric wavelengths along with feed pattern measurements in order to account for the level of ground contamination entering the sidelobes. A major asset of the experiment is the use of a wire mesh fence around the rim-halo shielded antenna with the purpose of levelling out and reducing this source of stray radiation for zenith-centered 1-rpm circular scans. We investigate the shielding performance of the experiment by means of a geometric diffraction model in order to predict the level of the spillover and diffraction sidelobes in the direction of the ground. Using 408 MHz and 1465 MHz feed measurements, the model shows how a weakly-diffracting and unshielded antenna configuration becomes strongly-diffracting and double-shielded as far-field diffraction effects give way to near-field ones. Due to the asymmetric response of the feeds, the orientation of their radiation fields with respect to the secondary must be known a priori before comparing model predictions with observational data. By adjusting the attenuation coefficient of the wire mesh the model is able to reproduce the amount of differential ground pick-up observed during test measurements at 1465 MHz.Comment: 14 pages, 17 eps + 1 gif figures and 4 Tables. Accepted for publication in A&AS. Fig.7 available at full resolution from http://www.das.inpe.br/~tello/publications.ht

Características agroclimáticas do município de Paragominas.

bitstream/item/63908/1/Oriental-Doc228.pd

Massive binaries and the enrichment of the interstellar medium in globular clusters

Abundance anomalies observed in globular cluster stars indicate pollution with material processed by hydrogen burning. Two main sources have been suggested: asymptotic giant branch stars and massive stars rotating near the break-up limit. We discuss the potential of massive binaries as an interesting alternative source of processed material. We discuss observational evidence for mass shedding from interacting binaries. In contrast to the fast, radiatively driven winds of massive stars, this material is typically ejected with low velocity. We expect that it remains inside the potential well of a globular cluster and becomes available for the formation or pollution of a second generation of stars. We estimate that the amount of processed low-velocity material that can be ejected by massive binaries is larger than the contribution of two previously suggested sources combined.Comment: 6 pages, 2 figures, to appear in the proceedings of IAU Symposium 266, "Star Clusters - Basic Galactic Building Blocks throughout Time and Space", 10-14 August 2009, at the general assembly in Rio de Janeiro, Brazi

Modelagem e estimação de parâmetros genéticos para características de crescimento do nascimento ao momento da seleção (378 dias) de machos Nelore.

Parâmetros genéticos para pesos (17.942 observações) obtidos em intervalos de 60 dias e para pesos padronizados do nascimento ao momento da seleção (378 dias de idade), de 2.582 animais machos da raça Nelore, foram estimados em análises univariadas pelo método da máxima verossimilhança restrita. Os modelos de análise incluíram os efeitos fixos de grupo de contemporâneos, mês de nascimento, idade da mãe e idade na pesagem como covariável. Três modelos aleatórios foram testados: o modelo1 (M1) ajustou para os efeitos genéticos direto (A) e materno (M) e de ambiente permanente materno (C); no modelo 2 (M2) excluiu-se M; e o modelo 3 (M3) excluiu-se M e C. O teste de razão de verossimilhança (LRT) detectou diferenças significativas (P<0,05), para todas as idades, de M2 e M1 com o modelo simples (M3). Com exceção do peso ao nascer (0,40), valores baixos (0,05 a 0,12) de h2 foram encontrados para M1 e M2 até 8 meses de idade e, após esse período, razoável aumento foi observado, chegando a 0,28 aos 13 meses. As estimativas do efeito de ambiente permanente materno em relação à variância fenotípica total (c 2) foram altas e permaneceram inalteradas entre M1 e M2. Efeitos maternos, não necessariamente decompostos (em genético e ambiente permanente), influenciaram o crescimento de machos Nelore. Modelos que contemplam efeitos maternos, além do genético direto, foram adequados para descrever a trajetória das variâncias ao longo das fases iniciais de crescimento de machos Nelore

Parâmetros genéticos e fenotípicos de medidas da infestação de fêmeas bovinas Caracu por carrapatos (Boophilus microplus).

SCANEA

Percutaneous ct fluoroscopy-guided core needle biopsy of mediastinal masses: Technical outcome and complications of 155 procedures during a 10-year period

Purpose: To evaluate technical outcome, diagnostic yield and safety of computed tomo-graphic fluoroscopy-guided percutaneous core needle biopsies in patients with mediastinal masses. Methods: Overall, 155 CT fluoroscopy-guided mediastinal core needle biopsies, performed from March 2010 to June 2020 were included. Size of lesion, size of needle, access path, number of success, number of biopsies per session, diagnostic yield, patient’s position, effective dose, rate of complications, tumor localization, size of tumor and histopathological diagnosis were considered. Post-interventional CT was performed, and patients observed for any complications. Complications were classified per the Society of Interventional Radiology (SIR). Results: 148 patients (age, 54.7 ± 18.2) underwent 155 CT-fluoroscopy-guided percutaneous biopsies with tumors in the anterior (114; 73.5%), middle (17; 11%) and posterior (24; 15.5%) mediastinum, of which 152 (98%) were technically successful. For placement of the biopsy needle, in 82 (52.9%) procedures a parasternal trajectory was chosen, in 36 (23.3%) a paravertebral access, in 20 (12.9%) through the lateral intercostal space and in 17 (11%) the thoracic anterior midline, respectively. A total of 136 (89.5%) of the biopsies were considered adequate for a specific histopathologic analysis. Total DLP (dose-length product) was 575.7 ± 488.8 mGy*cm. Mean lesion size was 6.0 ± 3.3 cm. Neoplastic pathology was diagnosed in 115 (75.7%) biopsies and 35 (23%) biopsy samples showed no evidence of malignancy. Minor complications were observed in 18 (11.6%) procedures and major pneumothorax requiring drainage insertion in 3 interventions (1.9%). Conclusion: CT fluoroscopy-guided percutaneous core needle biopsy of mediastinal masses is an effective and safe procedure for the initial assessment of patients with mediastinal tumors

Embrapa e as pesquisas de apoio à produção de ovos.

Projeto: 11.11.11.111

Fermion Helicity Flip Induced by Torsion Field

We show that in theories of gravitation with torsion the helicity of fermion particles is not conserved and we calculate the probability of spin flip, which is related to the anti-symmetric part of affine connection. Some cosmological consequences are discussed.Comment: 6 pages, to appear in Europhysics Letter

Cocoa byproduct in diets for dairy heifers.

ABSTRACT This study was conducted to evaluate the effect of substituting Tifton 85 hay (Cynodon sp. cv. Tifton 85) with levels of cocoa (Theobroma cacao) byproduct (0, 8, 16, and 24%, diet dry matter basis) in the diet of 16 Holstein × Gir heifers with an average body weight of 363.0±27.7 kg on their nutrient intake, digestibility, and protein balance. The experimental period was 17 days, and the sample collection period was five days. There was no effect of cocoa byproduct on nutrient intake. However, the byproduct affected the digestibility of dry matter, crude protein, neutral detergent fiber, and acid detergent fiber, all of which decreased as the level of inclusion of the byproduct in the diet was increased. Nitrogen balance was negatively affected by the inclusion of 24% cocoa byproduct. It is recommended to use cocoa byproduct up to the level of 16% to replace Tifton 85 grass hay in diets for dairy heifers