The On-orbit Calibrations for the Fermi Large Area Telescope

The Large Area Telescope (LAT) on--board the Fermi Gamma ray Space Telescope began its on--orbit operations on June 23, 2008. Calibrations, defined in a generic sense, correspond to synchronization of trigger signals, optimization of delays for latching data, determination of detector thresholds, gains and responses, evaluation of the perimeter of the South Atlantic Anomaly (SAA), measurements of live time, of absolute time, and internal and spacecraft boresight alignments. Here we describe on orbit calibration results obtained using known astrophysical sources, galactic cosmic rays, and charge injection into the front-end electronics of each detector. Instrument response functions will be described in a separate publication. This paper demonstrates the stability of calibrations and describes minor changes observed since launch. These results have been used to calibrate the LAT datasets to be publicly released in August 2009.Comment: 60 pages, 34 figures, submitted to Astroparticle Physic

Autoantibodies against type I IFNs in patients with life-threatening COVID-19

Interindividual clinical variability in the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is vast. We report that at least 101 of 987 patients with life-threatening coronavirus disease 2019 (COVID-19) pneumonia had neutralizing immunoglobulin G (IgG) autoantibodies (auto-Abs) against interferon-w (IFN-w) (13 patients), against the 13 types of IFN-a (36), or against both (52) at the onset of critical disease; a few also had auto-Abs against the other three type I IFNs. The auto-Abs neutralize the ability of the corresponding type I IFNs to block SARS-CoV-2 infection in vitro. These auto-Abs were not found in 663 individuals with asymptomatic or mild SARS-CoV-2 infection and were present in only 4 of 1227 healthy individuals. Patients with auto-Abs were aged 25 to 87 years and 95 of the 101 were men. A B cell autoimmune phenocopy of inborn errors of type I IFN immunity accounts for life-threatening COVID-19 pneumonia in at least 2.6% of women and 12.5% of men

Untangling the effects of overexploration and overexploitation on organizational performance: The moderating role of environmental dynamism

Because a firm's optimal knowledge search behavior is determined by unique firm and industry conditions, organizational performance should be contingent oil the degree to which a firm's actual level of knowledge search deviates from the optimal level. It is thus hypothesized that deviation from the optimal search, in the form of either overexploitation or overexploration, is detrimental to organizational performance. Furthermore, the negative effect of search deviation oil organizational performance varies with environmental dynamism: that is, overexploitation is expected to become more harmful. whereas overexploration becomes less so with all increase in environmental dynamism. The empirical analyses yield results consistent with these arguments. Implications for research and practice are correspondingly discussed

Bacteriophage mv4 site-specific recombination: the central role of the P2 mv4Int-binding site.

International audienc

Fontes de contaminação por Staphylococcus aureus na linha de processamento de queijo prato Identification of main sources of contamination with Staphylococcus aureus in Prato cheese manufacturing process

Com o objetivo de identificar as principais fontes de contaminação por Staphylococcus aureus e Staphylococcus produtores de coagulase (SC+), avaliou-se o processo de fabricação de queijo prato em um laticínio de Lavras, MG, durante os meses de outubro de 2000 a abril de 2001. As análises microbiológicas foram feitas no leite cru, no leite pasteurizado resfriado, nas mãos e antebraços dos funcionários, na salmoura, na água de imersão das fôrmas e no queijo embalado. Contagens elevadas de SC+ e de S. aureus (4x10³ a 4,8x10(6) UFC/ml e 4x10³ a 3,3x10(5) UFC/ml, respectivamente) foram encontradas em quatro avaliações no leite cru. Após a pasteurização, as contagens foram reduzidas a <1 UFC/ml. Em três das cinco avaliações, o queijo prato apresentou contagens de SC+ (10(4), 10(5) e 2,3x10(5) UFC/g) superiores às permitidas pela legislação vigente. A água de imersão das fôrmas e a salmoura apresentaram contagens de SC+ e S. aureus inferiores a 1 UFC/ml não se constituindo em importantes fontes de contaminação. As mãos e os antebraços dos funcionários foram possivelmente as fontes de contaminação do queijo, isto é, alta contagem nos queijos estava associada à contagem elevada nas mãos (4x10² UFC/cm²) ou nos antebraços (4,7x10² e 3,3x10³ UFC/cm²) dos manipuladores.<br>In order to identify the main sources of contamination with Staphylococcus aureus and Staphylococcus coagulase positive (SC+), a manufacture process of prato cheese in a plant located in Lavras, State of Minas Gerais, was evaluated five times from October/2000 to April/2001. Raw and pasteurized milk, hand and forearms of cheese makers, brine, hoops flushing water and cheeses were analyzed for SC+ and S. aureus. High counts of SC+ and S. aureus (4x10³ to 4.8x10(6) CFU/ml and 4x10³ to 3.3x10(5) CFU/ml, respectively) were found in raw milk in four evaluations, but they decreased to values lower than 1 CFU/ml after pasteurization. In three evaluations, counts of SC+ in prato cheese samples were above legal limits (10(4), 10(5) and 2.3x10(5) CFU/g). The hoops flushing water and brine were not important contamination sources, both with counts lower than 1CFU/ml. The cheese makers probably were the main source of contamination, since high counts in cheese were correlated to high counts in their hands (4x10² CFU/cm²) or forearms (4.7x10² and 3.3x10³ CFU/cm²)