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Recovery plays distinct roles in nanostructured and coarse-grained metallic materials. While static and dynamic recovery usually soften work-hardened, coarse-grained materials, static recovery has been shown to strengthen nanostructured metals. This study extends this understanding by demonstrating that dynamic recovery can also strengthen nanostructured metals under deformation. Tensile, creep, and plane strain compression tests on nanostructured aluminum reveal a trend of increasing strain-hardening with decreasing strain rate and increasing temperature. Molecular dynamics simulations further indicate that sudden strain rate reductions lead to an initial drop in flow stress, followed by strain hardening. These findings suggest that dynamic recovery could serve as an effective strengthening mechanism for nanostructured metals, offering improvements in uniform elongation.

The effect of high pressure torsion processing on mechanical properties and corrosion behavior of pure magnesium and Mg-Zn, Mg-Zn-Ca, Mg-Li-Y and Mg-Y-RE alloys is investigated. Micro-tomography and SEM characterization are used to estimate corrosion rate and evaluate non-uniform corrosion features. The results show that severe plastic deformation processing improves the strength of all magnesium alloys, but deformation localization can take place in the Mg-Zn-Ca and Mg-Y-RE alloys. The occurrence of deformation localization is associated with low strain rate sensitivity in these alloys and with severe corrosion localization. Pure magnesium and Mg-Zn and Mg-Li-Y alloys display good corrosion resistance with a low corrosion rate and maintain integrity after 28 days of immersion in Hank's solution.

There has been a great interest in developing zinc-based composites for biological applications. Mixing bioactive particles and obtaining a well-dispersed structure is not straight forward though. The present study reports a novel processing route in which zinc particles are mixed with hydroxyapatite and bioactive glass particles and consolidated at room temperature using high-pressure torsion. The composites display good dispersion of second phase particles, enhanced strength and an increased corrosion rate in the Hank’s balanced salt solution. The incorporation of these particles can be used to tailor the corrosion rate of zinc. It is shown that the surface layer of the corrosion product in the zinc-bioactive particle composites is richer in calcium and phosphorous than the pure zinc counterpart.

There is a great interest in improving mechanical testing of small samples produced in the laboratory. Plane strain compression is an effective test in which the workpiece is a thin sheet. This provides great potential for testing samples produced by high-pressure torsion. Thus, a custom tool was designed with the aim to test 10 mm diameter discs processed by this technique. Finite element analysis is used to evaluate the deformation zone, stress and strain distribution, and the accuracy in the estimation of stress–strain curves. Pure magnesium and a magnesium alloy processed by high-pressure torsion are tested using this custom-made tool. The trends observed in strength and ductility agree with trends reported in the literature for these materials.

The purpose of this study was to analyze helicopter emergency medical service (HEMS) transport with secondary land ambulance transfer, comparing landings performed inside and outside the hospital complex to the emergency department. This was a cross-sectional observational study of HEMS transports of trauma patients between 2016 and 2018 in southern Brazil. Patients were attended by the HEMS team at the trauma site or stabilized in hospitals nearby and subsequently referred to trauma centers. In this region, no trauma centers have their own helipads so helicopters land in remote areas close to the hospital, which may be inside or outside the hospital complex. Both landings require ground emergency medical service transport, with off-site landings necessitating ground emergency medical service transport via public access roads to reach the hospital. Data were analyzed using descriptive statistics, and on-site and off-site transport times were compared using a t -test for independent samples. Of 176 transports, 28.5% resulted in on-site landings, whereas 71.5% occurred off-site. The ground transport time when the landing zone was off-site was 5 minutes longer than on-site (P <.001). Off-site landings result in longer transports to the emergency room. The construction of helipads in trauma centers can reduce transport time, in addition to reducing the costs and sequelae of trauma. [ABSTRACT FROM AUTHOR]

• The Northwest, Central-Western, West and South-Central regions of Paraná stood out with the highest rates of lethal violence against woman. • Most cities with the highest Relative Risks (RR) for the occurrence of lethal violence against women were concentrated in Northwest, West, South Central and Metropolita of Paraná. • There was a positive association between lethal violence against women and the percentage of mothers who were heads of households, without having completed elementary school and with at least one child under 15 years. • Male homicide rates, rates of non-lethal violence against women and the presence of woman mayors and councilors in the cities were also associated. estimate the risk for the occurrence of lethal violence against women and to identify the associated factors in the state of Paraná. ecological study of deaths of women aged between 15 and 59 years, victims of aggression. The units of analysis were the cities of Paraná. Latent Bayesian Gaussian models with negative binomial probability distribution were used. The modeling considered intercept, spatial random effects and covariates, performed with the deterministic Integrated Nested Laplace Approximations approach. There was a positive association between lethal violence against women and the percentage of mothers who were heads of households. Finally, male homicide rates, rates of non-lethal violence against women and the cities with women mayors and councilors were also associated. This type of violence was associated with low education, structural violence and the participation of women in politics. [ABSTRACT FROM AUTHOR]