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Titanium dioxide nanotubes (TNTs) have been extensively researched for their enhanced biomedical characteristics, including biocompatibility, cell apposition, and growth morphology. However, there is a significant concern in metallic medical devices owing to micro-movements between implants and bone in aggressive environments due to wear and corrosion synergies, leading to adverse body responses and implant failure. In this study, TNTs on Commercially Pure titanium (C.P. Ti) with three different thickness layers were grown to correlate their corrosion and wear behavior. Initially amorphous after anodization, TNTs underwent annealing at 450 °C for 2 h to transform the distorted, into a crystalline structure. The characterization included X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray (EDX), X-ray Photoelectron Spectroscopy (XPS), and contact profilometry. Potentiodynamic polarization (PD) and tribocorrosion tests were conducted in Simulated Body Fluid Electrolyte (SBF). SEM micrographs showed TNT thickness layers of 314, 691, and 5280 nm, and X-ray Diffraction showed anatase transformation post-annealing. Results confirmed a significant influence of TNT thickness layers on corrosion and tribocorrosion properties, with higher current density obtained from PD for thicker TNTs layers, associated with surface fluorine content. During tribocorrosion, annealed samples demonstrated lower corrosion tendency, potential drop, and coefficient of friction. Morphology of worn surfaces and volumetric wear rate varied with TNT thickness layer and thermal treatment.

This study assessed leaf fluxes of CO2, CH4 and biogenic volatile organic compounds (BVOC) for two common urban tree species, Platanus × acerifolia (exotic) and Schinus molle (native), widely distributed in Santiago, Chile. The emission factors (EF) and the Photochemical Ozone Creation Index (POCI) for S. molle and P. × acerifolia were estimated. The global EF was 6.4 times higher for P. × acerifolia compared with S. molle, with similar rates of photosynthesis for both species. Isoprene represented more than 86% of the total BVOCs leaf fluxes being 7.6 times greater for P. × acerifolia than S. molle. For P. × acerifolia, BVOCs represented 2% of total carbon fixation while representing 0.24% for S. molle. These results may suggest that plant species growing outside their ecological range may exhibit greater BVOCs leaf fluxes, proportional to photosynthesis, compared to well-adapted ones. The results found may contribute to better urban forest planning.

Abstract This work analyzes the meanings attributed to alcohol consumption and the care strategies used by an indigenous group in Rio Grande do Norte (Brazil) by means ofa qualitative research involving residents and leaders. The results generated three analytical axes: determinants of alcohol consumption, health care settings, and alcohol use in the context of the COVID-19 pandemic. It was found that the use of alcohol in the community has been marked by historical movements that have altered the modes of existence and limited access to traditionally occupied lands. Alcohol consumption appeared as a naturalized phenomenon, associated with social and health problems that are aggravated by the lack of public assistance perceived by the community.

Most theoretical accounts in the current literature on North American integration consider the implementation of side and parallel environmental agreements to the North American Free Trade Agreement (nafta) and their corresponding institutions either a side-effect of the national governments' pursuit of their economic interests or the result of successful pressure by non-governmental organizations to include their socio-environmental demands in the treaty. These opposite explanations closely resemble liberal intergovernmentalist and transnational-focused accounts used to explain the occurrence and progression of regional integration in Europe. This article reviews and challenges both accounts and argues that they both assess inadequately the interests of governmental and transnational actors and their roles and relative influence in determining the outcome of the negotiations of the nafta side and parallel agreements on the environment. It proposes that a revised liberal intergovernmentalist account that considers the non-economic national interests of nation-states would explain better the pursuit and negotiation of nafta's environmental side and parallel agreements and the institutional structure that resulted from them. [ABSTRACT FROM AUTHOR]

Para alguns povos indígenas da América Latina, o uso de bebidas alcoólicas é anterior à chegada dos colonizadores. Para outros, os contatos interétnicos ao longo da história alteraram profundamente os sentidos e as relações com essas substâncias. O presente artigo revisa a literatura dos últimos anos sobre o consumo de álcool por povos indígenas latino-americanos, compreendendo aspectos históricos, sociais e de saúde a ele associados. Os resultados indicam que o uso precoce de bebidas alcóolicas, a perda de referenciais identitários, mudanças nos modos de vida, proximidade com centros urbanos, êxodo migratório, marginalização e discriminação social são fatores de risco ao consumo prejudicial de álcool entre povos indígenas. Constatou-se ainda uma carência de pesquisas epidemiológicas que prejudicam o dimensionamento de demandas relativas ao uso prejudicial de álcool e dificultam o planejamento e execução dos serviços de saúde.

O tabagismo é um grave problema de saúde pública no Brasil. O presente trabalho investigou o uso dos cigarros eletrônicos como possibilidade para reduzir os danos do consumo de tabaco. Realizou-se uma revisão narrativa de literatura, privilegiando artigos em revistas científicas, livros e outras fontes relevantes. Os resultados indicam que dispositivos eletrônicos para fumar podem ser menos prejudiciais à saúde se comparados a cigarros combustíveis e, portanto, têm potencial de serem utilizados para reduzir os danos do consumo de tabaco. Por outro lado, podem levar populações mais vulneráveis à iniciação ao tabagismo e ainda requerem estudos a fim de avaliar os efeitos na saúde a longo prazo. Da mesma forma que os cigarros combustíveis, conclui-se que cigarros eletrônicos, se regulamentados, devem ser submetidos a programas de controles austeros, incluindo, por exemplo, políticas tributárias, de proteção a não fumantes e restrição de publicidade.

Samples with 40% vol. of pores and a pore size distribution between 100 and 500 µm were produced by powder metallurgy from Ti6Al4V alloy powders. Sintering was performed at 1300 °C during one hour in an inert Argon atmosphere in a vertical dilatometer. The compressive strength and the porosity of these samples was investigated before and after compression tests through X-ray microtomography. The values of the elastic modulus (8GPa) and yield strength (80MPa) are within the range of those used in bone implants. Porosity leads to greater deformation whereas fracture of compacts occurs perpendicularly to the applied load. It was determined that the origin of the failure is generated by rupture of interparticle necks and, large pores enhance the propagation of cracks.

Aborda as questões socioculturais que envolvem o uso da folha de coca nas regiões andina e amazônica. O estudo é de natureza teórica, sendo privilegiados artigos científicos e entrevistas com profissionais conceituados em revistas e jornais. Os resultados da pesquisa sugerem que a associação indiscriminada da coca à cocaína e, consequentemente, ao narcotráfico, parte de um preconceito construído historicamente que se sobrepõe às raízes históricas e culturais do uso milenar da planta. Cabe à psicologia, como ciência, romper o silêncio frente às questões indígenas e compreender a dinâmica dos processos socioculturais desses povos para se fazer atuar em espaços que exigem tratamentos diferenciados.

Resumo O Brasil se destaca mundialmente na redução do tabagismo devido a suas eficazes políticas de controle. O artigo analisa, por meio de revisão narrativa, a natureza das discussões científicas que embasaram essas políticas públicas, por meio de perspectivas históricas, sociais, sanitárias e econômicas. Ressalta que as medidas associadas a essas questões têm sido marcadas por disputas de interesses entre as indústrias fumageiras e organizações de saúde. Explora temas ligados a publicidade, redução de danos, políticas tributárias e ações de proteção a não fumantes. Aponta para novas determinações sobre a publicidade de tabaco e sugere, por análise comparativa, veto à propaganda de bebidas alcoólicas no país.