10 research outputs found
Stress Rate Effect on the Pseudoelastic Behaviour of CuZnAl Single Crystals
Tensile pseudoelastic tests performed on elaborated single crystals show that the width of hysteresis loops and the slope of the stress-strain curves during phase transformation increase as the applied stress rate increases. In the first elementary model without mechanical dissipation, the integration of heat equation permits the qualitative description of hysteresis loop. The second model with a non-convex free energy and mechanical dissipation allows us a quantitatively good modeling of loading rate effects
Spatial trends in congenital malformations and stream water chemistry in Southern Brazil
The incidence of variable congenital malformation (CM) among 399 municipalities in the state of ParanĂĄ, southern Brazil, suggests the etiological role of environmental factors. This study examined a) environmental concentrations of chlorine anions (Clâ) associated with organochlorines (OCs) and b) associations between these chemicals and agricultural output with CMs using a geographical information system. In one of the three years during the sampling period (2008, 2009 or 2010) Clâ, dichlorodiphenyltrichloroethane (p,pâČ-DDT), dichlorodiphenyldichloroethylene (p,pâČ-DDE), dichlorodiphenyldichloroethane (p,pâČ-DDD), and endosulfan levels were measured in 465 (465/736, 63%) catchment basins. Agricultural outputs for crops during 2006â2010 were also evaluated (t/km2). Further, CM kernel density for the 399 municipalities in ParanĂĄ during 2007â2014 was investigated. Clâ levels increased significantly in one of the three years (2008, 2009 or 2010) in western catchment basins, compared to 1996 (p < 0.0001). The municipalities were divided according to the obtained Clâ levels, where sub-region C2 (centralâsouthern) < 1.8 mg/L †sub-regions C1 (northernâwestern) and C3 (easternâsouthern). We identified 8756 cases of CMs among 1,221,287 newborns (NB) in all sub-regions. C1 had higher DDT-DDE-DDD (p,pâČ-DDT + p,pâČ-DDE + p,pâČ-DDD) concentrations, agricultural output, and CM kernel density. C2 and C3 had minor agricultural outputs (per square kilometer) and CM densities. A 2.96 mg/L increase in Clâ between sub-regions C1 and C2 was co-localized with a 45% increase in CM density (spatial relative risk = 1.45, CI 95%: 1.36â1.55). C1 had the highest log likelihood ratios (p = 0.001) identified via SaTScan clustering analyses. Organochlorines and other toxic chlorinated chemicals may contribute to CMs in humans, and these chemicals are ultimately transformed and release Clâ in rivers. Higher Clâ levels were correlated significantly with higher agricultural productivity, DDT-DDE-DDD levels, and CMs in some parts of the northern and western sub-regions (C1)650112781291CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTĂFICO E TECNOLĂGICO - CNPQCOORDENAĂĂO DE APERFEIĂOAMENTO DE PESSOAL DE NĂVEL SUPERIOR - CAPESsem informaçãosem informaçãoThis project was funded by grants from the ParanĂĄ State Secretary of Science, Technology and Higher Education (No. 026/06/SETI/Geomedicina, 2006â2011), Brazilian National Council for Research and Development (CNPq, 2016â2018) and Coordenadoria de Aperfeiçoamento de Pessoal de Ensino Superior (CAPES, 2011â2018