2,549 research outputs found
Lensing Magnification and QSO-Galaxy Cross-Correlations: Observations, Theory and Simulations
We review observations and gravitational lensing theory related to the
magnification of background QSOs by intervening overdensities, and the induced
cross-correlation between sources and foreground galaxies. We pay special
attention to simulations, and present some preliminary results from high
resolution cluster simulations, which show the role of the halo core and
substructure on non-linear magnification. For massive clusters, deviations from
the weak gravitational lensing regime are significant on arcmin scales and
bellow. The accumulated knowledge in the field already shows that gravitational
lensing magnification is an important astrophysical and cosmological tool.Comment: 6 pages. Presented at "100 years of relativity -- international
conference on classical and quantum aspects of gravity and cosmology", 200
Ideologies and Rhetoric
Brazil has had a distinctive definition of national and racial identity, and
it has changed considerably over time, and at each time held out different
possibilities for social mobility and citizenship. This paper traces changing
relationship between black identities and citizenship through four periods in
Brazilian history: abolition, black protests in the 1930s, postwar re-
democratization and the democratic movement against the military dictatorship
in the 1970s. It emphasizes how the complex intersection of nation, social
relations, class and race has had profound effects on not only the categories
used to label people, but also on the nuanced definition of the goal of
efforts to overcome inequality
Coupled Thermo-Hydro-Mechanical and Chemical Analysis of Expansive Clay Subjected to Heating and Hydration
A fully coupled formulation combining reactive transport and an existing thermo-hydro-mechanical (THM) code is presented. Special attention has been given to phenomena likely to be encountered in clay barriers used as part of containment systems of nuclear waste. The types of processes considered include hydrolysis, complex formation, oxidation/reduction reactions, acid/base reactions, precipitation/dissolution of minerals and cation exchange. Both kinetically-controlled and equilibrium-controlled reactions have been incorporated. The total analytical concentrations (including precipitated minerals) are adopted as basic transport variables and chemical equilibrium is achieved by minimizing Gibbs Free Energy. The formulation has been incorporated in a general purpose computer code capable of performing numerical analysis of engineering problems. A validation exercise concerning a laboratory experiment involving the heating and hydration of an expansive compacted clay is described
A non-randomized comparative study using different doses of acyclovir to prevent herpes simplex reactivation in patients submitted to autologous stem cell transplantation
The reactivation of Herpes Simplex virus (HSV) occurs in 70% to 80% of patients submitted to autologous stem cell transplantation (ASCT); it increases the severity of chemotherapy-induced mucositis. Therefore, the use of acyclovir in ASCT patients is considered standard practice. However, the minimum dose needed to prevent reactivation is a matter of debate. We compared two doses of acyclovir in a non-randomized fashion in 59 patients submitted to ASCT: 32 patients received a dose of 125 mg/m2 IV every six hours and the subsequent 27 patients received a dose of 60 mg/m2 IV every six hours. Viral excretion was evaluated through weekly viral culture of oral swabs. Grade 4 mucositis was more frequent in Group 1 (p= 0.03). The reactivation rates in Groups 1 and 2 were 9% and 4%, respectively (p= 0.62, 95% confidence interval -7 - 18). Prophylaxis with reduced doses of intravenous acyclovir seems to be as effective as a higher dose in inhibiting HSV reactivation, with a significant reduction in cost. Prospective randomized studies are needed to confirm our conclusions.
Estilos de Liderança e Mecanismos de Aprendizagem em Organizações: Análise de suas Relações em uma Organização Financeira
This study aims to identify leadership styles thatpredict perceptions about organizational learningmechanims in a Brazilian financial organization. The data collection was undertaken in 2006supported by two measure scales: Organizational Learning Mechanisms Scale and ManagerialStyles Evaluation Scale. The sample was composed by506 people that filled in a Likert fivepointquestionnaire. Professional and biographic data from the participants of the research were alsocollected. Descriptive and inferencial analyses were undertaken and the results show thatrelationship leadership style was the better predictor of perceptions upon organizational learningmechanisms, specifically about internal and external acquisition, sharing, stowing and control ofknowledge in organizations. Research limitations are stated and research agenda and practicalrecommendations are done
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