Search for VHE gamma rays from SS433/W50 with the CANGAROO-II telescope

SS433, located at the center of the supernova remnant W50, is a close proximity binary system consisting of a compact star and a normal star. Jets of material are directed outwards from the vicinity of the compact star symmetrically to the east and west. Non-thermal hard X-ray emission is detected from lobes lying on both sides. Shock accelerated electrons are expected to generate sub-TeV gamma rays through the inverse-Compton process in the lobes. Observations of the western X-ray lobe region of SS433/W50 system have been performed to detect sub-TeV gamma-rays using the 10m CANGAROO-II telescope in August and September, 2001, and July and September, 2002. The total observation times are 85.2 hours for ON source, and 80.8 hours for OFF source data. No significant excess of sub-TeV gamma rays has been found at 3 regions of the western X-ray lobe of SS433/W50 system. We have derived 99% confidence level upper limits to the fluxes of gamma rays and have set constraints on the strengths of the magnetic fields assuming the synchrotron/inverse-Compton model for the wide energy range of photon spectrum from radio to TeV. The derived lower limits are 4.3 microgauss for the center of the brightest X-ray emission region and 6.3 microgauss for the far end from SS433 in the western X-ray lobe. In addition, we suggest that the spot-like X-ray emission may provide a major contribution to the hardest X-ray spectrum in the lobe.Comment: 7 pages, 8 figures, to be published in Astroparticle Physic

Testes de vigor na avaliação da qualidade fisiológica de sementes Erythrina velutina Willd. (FABACEAE - PAPILIONOIDEAE) Vigor tests in the evaluation of physiological quality of Erythrina velutina Willd. (FABACEAE- PAPILIONOIDEAE) seeds

A aplicação de testes de vigor de sementes tem sido fundamental para determinação da qualidade fisiológica de forma rápida e eficaz, destacando-se, os testes baseados no desempenho das plântulas como uma das opções disponíveis. Conduziu-se este trabalho, com o objetivo de avaliar a eficiência de testes de vigor para determinação da qualidade fisiológica de sementes de Erythrina velutina. Determinou-se em cinco lotes de sementes de E. velutina o teor de água e o peso de mil sementes e realizou-se os testes de germinação, emergência em campo, índice de velocidade de germinação e de emergência, comprimento e massa seca de plântulas do laboratório e campo. Os testes de campo (emergência de plântulas, índice de velocidade de emergência de plântulas e massa seca da parte aérea das plântulas) são eficientes na separação dos lotes de sementes de E. velutina em níveis de vigor.<br>The application of vigor tests of seeds has been fundamental as a fast and efficient form of determination of physiological seed quality, highlighting the tests based on the performance of seedlings as one of the available options. The objective of this study was to evaluate the efficiency of different vigor tests for the determination of the physiologic quality of Erythrina velutina seeds. In five lots of E. velutina seeds, water content and seed weight were determined. Tests for germination were performed for field seedling emergence, speed germination and emergence index, and length and dry matter weight of seedlings from both the laboratory and from the field. Field tests (seedling emergence, speed emergence index, and dry matter weight of the aerial part of seedlings) are efficient in the separation of the seed lots of E. velutina in vigor levels

Antibody induced injury to podocytes with proteinuria and foot process swelling in a transgenic (T16) mouse

T16 mice contain a human 3′ untranslated sequence of the Thy 1.1 gene. Unlike normal mice they express Thy 1.1 protein on the podocytes which was immuno-localized to podocyte apical and basal plasma membranes and filtration slit. When monoclonal anti-Thy 1.1 antibody (OX7) was injected in nonproteinuric heterozygous mice there was rapid podocyte foot process swelling and proteinuria. Immunofluorescence showed granular glomerular OX7 binding at one hour. Progressive loss of pedicels occurred with 17.9 ± 2.5, 14.4 ± 1.1 and 10.5 ± 3.5 per 10 nm glomerular basement membrane (GBM) remaining 1, 6 and 24 hours, respectively, after 1 mg OX7, vs 32.2 ± 2.0 in T16 mice given saline. Twenty-four hour proteinuria was OX7 dose-dependent, peaked at 1–3 days and reduced to near basal levels 9–11 days thereafter. Proteinuria was nonselective except at very low doses (0.1 mg OX7) where microalbuminuria was seen. F(ab′)2 OX7 administration also caused proteinuria in T16 mice. One milligram F(ab′)1 OX7 caused diffuse foot process swelling without manifest proteinuria in T16 mice. Anti-Thy 1.1 IgM monoclonal antibody did not produce the effects of OX7 in T16 mice. Foot process swelling was not modified by histamine or 5-hydroxytryptamine antagonists. OX7 did not cause complement activation or leucocyte infiltration, hence glomerular injury appeared to be mediated directly by the antibody