57 research outputs found

    The Influence of Dry Particle Coating Parameters on Thermal Coatings Properties

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    International audienceThe physical properties of coatings elaborated by plasma spraying, especially the mechanical properties are strongly influenced by some fifty operating parameters of the spraying process. Several studies have been conducted to correlate these operating parameters with the coating microstructure, via the behavior of molten particles in flight to be impacted against the surface substrate, well known as splats. Then, it is expected to build coatings with tailored properties for mechanical and even thermal applications (Fauchais & Vardelle, 2000). Simultaneously to the operating parameters of plasma spraying, characteristics of raw powder play an important role in the coating elaboration (Vaidya et al, 2001). Depending on the production process, particles feature different characteristics concerning shape, size, specific density, purity, etc. This has a significant influence on the resulting coating properties (Sampath et al, 1996). Consequently, it becomes mandatory to have an intensive knowledge about the powder characteristics in order to better control the behavior of inflight particles and, thus obtaining coatings with the expected performance. For the elaboration of composite coatings, it is commonly to use composite powders. However, different characteristics of powders are obtained from the variety of processes nowadays available for powder production, even for powders with the same chemical composition! (Kubel, 2000) Kubel has compared powders produced from different techniques for plasma spraying (atomization, agglomeration by spray-drying, melting and grinding, wet particle coating; sintering). A variety of powder characteristics is found for which the operating parameters for plasma spraying must be adapted to obtain deposits featuring the desired properties. From this, certain components or materials are fabricated by some of these methods or exclusively just one

    Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

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    Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≄20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≄30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

    AnĂĄlise comparativa das caracterĂ­sticas da serrapilheira e do solo em cafezais (Coffea arabica L.) cultivados em sistema agroflorestal e em monocultura, na Zona da Mata MG Comparative analysis of litter and soil characteristics under coffee (Coffea arabica L.) crop in agroforestry and monoculture systems

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    O aporte de serrapilheira em sistemas agroflorestais pode melhorar as caracterĂ­sticas quĂ­micas e fĂ­sicas do solo, diminuir a erosĂŁo e permitir a manutenção da umidade no solo por mais tempo. Isso faz dele um sistema alternativo de produção de cafĂ© em regiĂ”es com solos propensos Ă  degradação. Este trabalho teve como objetivo realizar uma anĂĄlise comparativa da quantidade e teor de nutrientes da serrapilheira e das caracterĂ­sticas de fertilidade e do teor de umidade dos solos, em cafeeiros cultivados sob sistemas agroflorestal e solteiro. A pesquisa foi realizada na Zona da Mata mineira, durante o perĂ­odo compreendido entre janeiro de 1999 e maio de 2000. O sistema agroflorestal contribuiu com 6,1 Mg ha-1 ano-1 de matĂ©ria seca de serrapilheira, no entanto o solteiro aportou 4,5 Mg ha-1 ano-1, ressaltando-se que esta Ășltima apresentou teor mais elevado de macronutrientes. O solo do sistema agroflorestal exibiu maior teor de umidade de 20-40 cm, maior capacidade de troca de cĂĄtions e soma de bases trocĂĄveis, maior teor de K, Ca, Mg, Cu e Zn em ambos os horizontes do solo e menor Ă­ndice de saturação de alumĂ­nio e alumĂ­nio trocĂĄvel na camada mais profunda do que o solo sob a monocultura. No cultivo solteiro, o solo apresentou maior teor de P e de matĂ©ria orgĂąnica, tanto na camada superficial quanto na profunda.<br>Coffee plants in agroforestry systems is an alternative to full sunlight cultivation, presenting the potential benefits of enhancing soil chemical and physical characteristics, reducing soil erosion, besides maintaining soil moisture for longer periods. This research aimed at comparing the quantity and nutrient concentration in the litter, soil fertility and soil moisture in coffee crops under full sunlight monocrop and in agroforestry systems, at the Zona da Mata, Minas Gerais, Brazil. The research was carried out between January 1999 and May 2000. The agroforestry system, contributed with 6.1 Mg ha-1 year-1 of litter dry matter while the monoculture produced 4.5 Mg ha-1 year-1, which presented higher nutrient content. The litter in monoculture presented higher nutrient content. The agroforestry system presented higher soil moisture content (20-40 cm depth) and K, Ca, Mg, Sum of Basis, Cation Exchange Capacity, Cu and Zn levels in both soil depth, besides lower aluminum saturation and Al values in deeper layer than soil of monocrop coffee. Soil under monoculture presented higher P and organic matter content than agroforestry system

    Reporting antimicrobial susceptibilities and resistance phenotypes in Acinetobacter spp: a nationwide proficiency study

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    GuĂ­a de TerapĂ©utica Antimicrobiana del Área Aljarafe, 3ÂȘ ediciĂłn

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    Coordinadora: RocĂ­o FernĂĄndez Urrusuno. Co-coordinadora: Carmen Serrano Martino.YesEstas guĂ­as son un recurso indispensable en los Programas de OptimizaciĂłn de AntibiĂłticos (PROA). No sĂłlo constituyen una herramienta de ayuda para la toma de decisiones en los principales sĂ­ndromes infecciosos, proporcionando recomendaciones para el abordaje empĂ­rico de dichos procesos, sino que son el patrĂłn/estĂĄndar de referencia que permitirĂĄ determinar la calidad o adecuaciĂłn de los tratamientos realizados. Las guĂ­as pueden ser utilizadas, ademĂĄs, como herramienta de base para la formaciĂłn y actualizaciĂłn en antibioterapia, ya que permiten mantener actualizados los conocimientos sobre las nuevas evidencias en el abordaje de las infecciones. Por Ășltimo, deberĂ­an incorporar herramientas que faciliten el proceso de toma de decisiones compartidas con el paciente. El objetivo de esta guĂ­a es proporcionar recomendaciones para el abordaje de las enfermedades infecciosas mĂĄs prevalentes en la comunidad, basadas en las Ășltimas evidencias disponibles y los datos de resistencias de los principales patĂłgenos que contribuyan a mejorar la calidad de la prescripciĂłn de antimicrobianos
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