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The purpose of this paper is to evaluate the fatigue process through the dynamic analysis of the global structural model and local static sub-modelling in a critical detail using the hot-spot stress approach. The detail was studied in three different positions at the “Alcácer do Sal” access viaduct, and the methodologies from the IIW and Eurocode EN 1993-1-9 were compared.

In this study, the fatigue life process based on the hot-spot stress approach was evaluated using a global dynamic analysis and a local sub-modelling based on a static analysis of welded connections in the “Alcácer do Sal” railway structure, Portugal, taking into consideration the recommendations from IIW and Eurocode EN 1993-1-9. The hot-spot stresses were calculated through the static analysis of the sub-model of the welded connection for each vibration mode with the aim to obtain the temporal stresses using the modal coordinates and modal stresses of the extrapolation points. The Ansys® and Matlab® softwares were used for the numerical analysis and the hot-spot stress calculations, respectively.

The proposed methodology/approach to obtain fatigue assessment is based on the modal analysis of the global structural model and local static sub-modelling. The modal analysis was used to extract the boundary conditions to be used in the local model to determine the temporal stresses of the extrapolation points. Based on the modal superposition method, the stresses as function of time were obtained for fatigue life evaluation of a critical detail by the hot-spot stress approach. The detail was studied in three different positions.

In the present study, a global-local fatigue methodology based on dynamic analysis of the global structural model and local static sub-modelling of the critical detail using the hot-spot stress approach is proposed. Herein, the modal analysis of the global structural model supported by the modal superposition method was used to obtain the matrix of modal coordinates. The static analysis of the local sub-model for each mode from the modal analysis of global structural model was done to estimate the hot-spot stresses. The fatigue damage calculation was based on S-N curve of the critical detail and rainflow method. The IIW recommendation proved to be more conservative compared to the proposed rules in the Eurocode EN 1993-1-9. The global-local modelling based on dynamic analysis is an important and effective tool for fatigue evaluation in welded joints.

The purpose of this paper is to investigate the fatigue performance of a welded detail from a composite steel-concrete railway twin girder bridge caused by a passenger train circulating at varying speeds, by identifying the dynamic amplification scenarios induced by resonance. For this purpose, the hotspot stress method is used, instead of the traditional nominal stress methods.

This paper assesses the fatigue behavior of a welded connection considering critical stress concentration locations (hotspot). Finite element analysis (FEA) is applied, utilizing both a global and a local submodel, made compatible by displacements field interpolation. The dynamic response is obtained through the modal superposition method. Stress cycles are extracted with the rainflow counting method and the fatigue damage is calculated with Palmgren-Miner’s rule. The feasibility of five submodels with different mesh densities, i.e. 1, 2, 4, 8 and 20 mm is verified.

An increase in the fatigue damage due to the resonance effect was found for the train traveling at a speed of 225 km/h. A good agreement between the computed fatigue damage for the submodels is achieved. However, a non-monotonic hotspot stress/fatigue damage vs mesh density convergence was observed with a peak observed for the 4 mm model, which endorses the mesh sensitivity that could occur when using the surface stress extrapolation detailed rules specified in the standards for the hotspot stress method.

Advanced dynamic analyses are proposed to obtain local stresses in order to apply a local method for the fatigue assessment of a bridge’s structure subjected to high-speed railway traffic on the basis of the mode superposition technique resulting in much less computing times.

The purpose of this paper is to seek to clarify whether the fair value (FV) of Brazilian banks securities is relevant for investors in times of crisis.

The information gathered for 14 quarters, 2007-2010, of a cross-sectional sample of banks was used for the purpose of explaining the value of shares based on amortized cost and the FV of securities, the book value of equity and the financial crisis. The return on shares was regressed based on the realized and unrealized gains and losses on securities, adjusted income and the crisis.

The results indicated that the FV is relevant. The results also corroborated the hypothesis that, during the crisis, there was a decrease in the relevance of the FV of securities since the accounting practices adopted in Brazil did not specify how to estimate FV, as required by SFAS 157, neither did they require disclosure of the FV hierarchy, as established International Financial Reporting Standards (IFRS) 7. It was concluded that FV has incremental explanatory power over equity, but not over amortized cost. Furthermore it possible to conclude that quarterly unrealized gains and losses on securities are not relevant, which could be explained by possible tax planning practices, since, in Brazil, the mark-to-market adjustment of securities is only deductible, or taxable, when settled. However, the realized and unrealized gains and losses are value-relevant during the period of financial crisis.

This study provides empirical evidence about the relevance of FV during the financial crisis in Brazil.

This paper aims to examine the origins and trajectory of the Brazilian corporate social responsibility (CSR) movement in relation to political economic developments in Brazil during and prior to the 2000s.

This paper relies on a historical political account that traces the evolution of the main actors in the CSR movement since the democratization period, details the contacts established with relevant political and civil society groups and outlines the adaptation of their agenda to the changing context.

The long association between a faction of Brazilian business and the Workers’ Party (PT) and the overlapping state – society relations characteristic of the Brazilian political economy explain the domestic and international standing of the Brazilian CSR movement, in particular since 2003 when Lula da Silva came to power.

The trajectory of Brazilian CSR and participation in related global initiatives cannot be explained through market-based or isomorphic approaches traditionally used to analyze the diffusion of governance mechanisms in the Global South. Rather, it highlights the relevance of local political structures in shaping involvement in global governance initiatives.

The purpose of this paper is to characterize real estate lease management of the São Paulo City Municipality (PMSP), the largest metropolitan region in Latin America, for the provision of public education, health and social assistance services.

In addition, the management was also evaluated by a direct analysis of the obtained data (lease paid, area of the property, agency, zone, region, neighborhood, contract date, etc.) and by statistical regressions.

The results showed that the following: real estate properties with the greatest discrepancy of amounts paid (when compared to other amounts paid by the city and the market) are in a pulverized category, called “Others”; PMSP faces difficulties tracking expiration dates, 18.9% of the assets are still in use, though present expired contracts; the category “Education” is the most expressive in expenses; there is a limit to the correlation between the size of the real estate and the lease price paid, and very large real estate do not have proportionally higher leases; the location only directly affects the lease value if it is in the central region of the Metropolis. There is no explicit relationship for leases in other regions.

This work is groundbreaking for helping to consolidate the literature on real estate management in developing countries. Factors that integrate and influence the management of real estate leases for government agencies in a Latin American metropolitan area have never before been reported in the literature.

This study aims to estimate the overall SARS-CoV-2 seroprevalence and evaluate the accuracy of an antibody rapid test compared to a reference serological assay during a COVID-19 outbreak in a prison complex housing over 13,000 prisoners in Brasília.

The authors obtained a randomized, stratified representative sample of each prison unit and conducted a repeated serosurvey among prisoners between June and July 2020, using a lateral-flow immunochromatographic assay (LFIA). Samples were also retested using a chemiluminescence enzyme immunoassay (CLIA) to compare SARS-CoV-2 seroprevalence and 21-days incidence, as well as to estimate the overall infection fatality rate (IFR) and determine the diagnostic accuracy of the LFIA test.

This study identified 485 eligible individuals and enrolled 460 participants. Baseline and 21-days follow-up seroprevalence were estimated at 52.0% (95% CI 44.9–59.0) and 56.7% (95% CI 48.2–65.3) with LFIA; and 80.7% (95% CI 74.1–87.3) and 81.1% (95% CI 74.4–87.8) with CLIA, with an overall IFR of 0.02%. There were 78.2% (95% CI 66.7–89.7) symptomatic individuals among the positive cases. Sensitivity and specificity of LFIA were estimated at 43.4% and 83.3% for IgM; 46.5% and 91.5% for IgG; and 59.1% and 77.3% for combined tests.

The authors found high seroprevalence of anti-SARS-CoV-2 antibodies within the prison complex. The occurrence of asymptomatic infection highlights the importance of periodic mass testing in addition to case-finding of symptomatic individuals; however, the field performance of LFIA tests should be validated. This study recommends that vaccination strategies consider the inclusion of prisoners and prison staff in priority groups.