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This paper quantifies green roofs energy savings which is a challenging topic, namely in Mediterranean climate with distinct heating and cooling seasons. The thermal behavior of a green roof case study in Lisbon, Portugal, was assessed through an experimental campaign during heating and cooling periods of the year of 2013. These experimental results were then used to calibrate a building energy simulation in EnergyPlus. After validation, the numerical model was used to compare the energy performance of intensive, semi-intensive and extensive green roofs. The three green roof types lead to similar heating energy needs but extensive green roof solution shows higher cooling energy needs than semi-intensive and intensive ones, of 2.8 and 5.9 times more, respectively. Furthermore, the performance of each type of green roof and different insulation properties was compared to traditional roof solutions. With no thermal insulation, extensive green roofs require 20% less energy use than black roofs and show a similar annual behavior than white roofs. Semi-intensive and intensive green roofs energy use is 60–70% and 45–60% lower than black and white roofs, respectively. Well insulated roofs do not take full advantage of evapotranspiration cooling effects, which is particularly noticeable when comparing with high reflective white roofs. [ABSTRACT FROM AUTHOR]

This paper reports on the nonlinear static analysis of 2D concrete structures using a non-conventional finite element formulation. The nonlinear behavior of the material is modelled with a continuum non-local and isotropic damage model. While the material’s behavior is linear elastic, a pure hybrid-displacement Trefftz formulation is adopted. From the point where the concrete assumes a nonlinear behavior, this approach degenerates into a hybrid-displacement formulation. The computational performance is tested by means of two numerical examples which show that the proposed model predicts correctly the global behavior of the structures. [Copyright &y& Elsevier]

Abstract: This communication reports on the nonlinear analysis of 2D concrete structures using an hybrid-mixed stress formulation and continuum damage mechanics. The finite element model adopted is based on the direct and independent approximation of three fields: the stress and displacement fields in the domain of each element and the displacement field on the static boundary. The nonlinear behavior of the material is modelled using both a local and nonlocal isotropic damage model. Two numerical examples are presented to illustrate and validate the use of such numerical technique. [Copyright &y& Elsevier]

Background Renal transplant patients have a higher incidence of non-melanoma skin cancer (NMSC). Previous studies hypothesized that human leukocyte antigen (HLA), especially types DR1, DR4, and DR7, may influence the incidence of these tumors. This study investigates the association between NMSC and the presence of HLA DR1, DR4, and DR7 in renal transplant patients in southern Brazil. Methods In a historical cohort study, 1032 patients who underwent renal transplantation during the period from January 1993 to December 2006 were examined to identify occurrences of NMSC and HLA status prior to transplant. Results Of the 1032 patients examined, 59 (5.71%) developed NMSC (squamous cell carcinoma [SCC]: 2.42%; basal cell carcinoma [BCC]: 1.74%; both: 1.55%). The presence of HLA DR1 was associated with a higher probability of developing any NMSC and particularly with developing BCC ( P < 0.05). There was no statistically significant association between the presence of HLA DR4 or DR7 and the occurrence of NMSC in this sample. Conclusions HLA DR1 appears to be associated with the development of BCC, as well as with the higher number of NMSC lesions in renal transplant patients. This study supports the trend to associate the DR1 allele with BCC and not with SCC. [ABSTRACT FROM AUTHOR]