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In this paper, the influence of single equal channel angular pressing, ECAPressing, pass and processing temperature on crystallinity evolution and mechanical behaviour of the polymers polypropylene, PP, and high-density polyethylene, HDPE was investigated. ECAPressing tests were performed at the temperatures of 25, 50, 75 and 100°C for HPDE and 25, 90 and 120ºC for PP. The materials mechanical behaviour before and after ECAPressing tests was evaluated from room temperature compression tests while their crystallinity changings were analyzed through differential scanning calorimetry, DSC, experiments. In terms of strengthening and by comparison with as-received materials, it was observed an interesting efficiency of ECAPressing performed at 100°C for HDPE and 120°C for PP. In relation to crystallinity evolution, the results obtained from DSC tests showed its considerable increasing for higher pressing temperatures also by comparing either to as-received conditions or after single pass of equal channel angular pressing at room temperature.

Em virtude da pandemia da COVID-19, vivenciada desde março de 2020, ações de enfrentamento com rápida aplicação se fazem necessárias. Conforme amplamente noticiado na imprensa, respiradores artificiais são equipamentos de grande importância na luta contra a COVID-19, principalmente em casos graves. Devido ao seu alto custo, pesquisas têm sido realizadas visando o desenvolvimento de respiradores artificiais de baixo custo, através da automatização do reanimador manual conhecido como AMBU. Neste contexto, foi desenvolvido por pesquisadores do campus Santos Dumont, do Instituto Federal do Sudeste de Minas Gerais, um protótipo semelhante. Posto isso, visando responder a seguinte questão norteadora: o desenvolvimento de respiradores artificiais de baixo custo baseados na automatização de reanimadores manuais é viável para o atendimento de pessoas com deficiência respiratória? Este trabalho tem como objetivo avaliar a viabilidade do protótipo desenvolvido no referido campus, nos atendimentos de emergência a pacientes com dificuldades respiratórias. Para isso, foram realizados ensaios pré-clínicos em bancadas, com um pulmão de testes e um boneco inflável de RCP, entre outros equipamentos capazes de validarem seu funcionamento. Nesse contexto, seu funcionamento foi demonstrado e os resultados dos testes foram submetidos a avaliação de uma banca composta por especialistas da área da saúde, a fim de comprovar, através de formulários e laudos clínicos, se o protótipo é viável ao que se propõe e se está apto a ser produzido por uma empresa autorizada pela ANVISA e testado em humanos, além de indicar em que situações ele pode ser usado, conforme orienta a RDC 386/2020 da ANVISA. Desta forma, a banca composta por seis avaliadores, avaliou o desempenho do protótipo em cinco categorias: Usabilidade, Segurança, Segurança elétrica, Ventilação mecânica e Viabilidade. Para isso, analisaram 54 proposições relacionadas às categorias mencionadas, totalizando, portanto, em de 324 avaliações, das quais, de acordo com os avaliadores, 90% destas atestaram que o protótipo é fácil de ser usado, seguro, fornece ventilação adequada e é viável ao atendimento a pacientes com diferentes níveis de dificuldades respiratórias. Portanto, após as avaliações, constatou-se que o projeto está apto a ser produzido por uma empresa autorizada pela ANVISA, podendo ser testado em humanos, observados os critérios da RDC 386/2020 da ANVISA.

O Programa Parlamento Jovem tem potencial para criar oportunidades de participação democrática e contribuir com os elementos curriculares previstos na nova Base Nacional Comum Curricular - BNCC. De modo comparativo analisou-se duas experiências pedagógicas sobre este Programa executado por duas Câmaras Municipais. O objetivo foi traçar paralelos entre estes programas de modo a ilustrar seus limites e possibilidades, do ponto de vista pedagógico e de efetividade em seu potencial formativo para cidadania, participação e compreensão sobre política. Foi destacada a relação com a vida escolar, compreensão de cidadania e trabalho e protagonismo juvenil a partir de entrevistas realizadas com as responsáveis pedagógicas atuais de cada Programa. O programa agrega-se à instituição escolar como um mecanismo de apoio e suporte para a construção das competências e habilidades sobre cidadania, política e participação social. A efetividade político-pedagógica destes programas pode ser maior com apoio da Câmara, parcerias institucionais e compreensão das necessidades dos estudantes.

(1) Background: It is of great importance to promote functional capacity and positive lifestyles, since they contribute to preventing the progression of frailty among the older adults. The aim of this study was to evaluate the effect of active aging-in-place–rehabilitation nursing program (AAP-RNP) on the functional capacity and lifestyles of frail older adults. (2) Methods: This was a single-blinded, two-group, randomized, controlled trial of 30 frail older people enrolled at a Health-care unit in Portugal between 2021 and 2022. The duration of the program was 12 weeks, and the sessions took place at the participants’ homes. We used as instruments the Tilburg Frailty Indicator; Fried frailty phenotype; Senior Fitness Test battery; Barthel Index; Lawton Index; handgrip strength measurement; Tinetti Index; Individual lifestyle profile; and Borg’s perception of effort. (3) Results: Post-program, there was an improvement in multidimensional and physical frailty, functional capacity, balance, and perceived exertion (p < 0.05) in the experimental group. Among the older adults’ lifestyles, we observed significant improvements in physical activity habits, relational behavior, and stress management. (4) Conclusions: Rehabilitation nurses have a relevant role, and the AAP-RNP seems to be effective in improving functional capacity and lifestyles in frail older adults. info:eu-repo/semantics/publishedVersion

Despite the considerable morbidity and mortality of Yellow fever virus (YFV) infections in Brazil, as well as its widespread presence in non-human primate host, our understanding of disease outbreaks is hampered by limited viral genomic data. Determining the timing and spatial corridors of YFV spread, as well as the geographic hotspots that link the endemic north of the country with epidemic extra-Amazonian regions, are central to predicting and preventing future outbreak events and epidemics. Here, we tracked the recent spread of the virus by integrating genome sequences of new YFV infections sampled from infected non-human primates and humans with both epidemiological and vector data. Through a combination of phylogenetic and epidemiological models we reconstructed the recent transmission history of YFV within different epidemic seasons in Brazil. A suitability index based on the highly domesticatedAedes aegyptiwas able to capture the seasonality of reported human infections. Spatial modelling revealed spatial hotspots with both past reporting and low vaccination coverage, which coincided with many of the largest urban centres in the Southeast. Phylodynamic analysis unravelled the circulation of three distinct YFV lineages, and provided proof of the directionality of a known spatial corridor of viral spread that connects the endemic North with the extra-Amazonian basin. This study illustrates that genomics linked with field sampling of animals and humans within a One Health framework can provide new insights into the landscape of YFV transmission, augmenting traditional approaches to infectious disease surveillance and control.

This study is based on the numerical simulation of the mechanical response of yttrium-stabilized zirconia ceramic (3Y-TZP) dental implants as a function of their intrinsic geometry and masticatory loads. Samples (n=20) of 3Y-TZP ceramics were compacted, sintered at 1500 °C - 2h, and characterized by relative density, X-Ray diffraction (XRD), and scanning electron microscopy (SEM). The elastic parameters (modulus of elasticity and Poisson ratio), used in the numerical simulations, were measured by the Impulse Excitation Technique, and the bending strength was obtained using piston-on-three-balls testing. An authorial implant design and, comparatively, commercial implant CAD models were used in this study as an initial geometry of dental implant in a typical adult mandible anatomy. From CAD and CAE techniques, finite element models were generated for all implant geometries. Loading cases were considered based on different intensities (100N to 500N) and orientation angles (45° or 90°) to reproduce the human masticatory efforts. The numerical predictions were compared with finite element simulations of gold-standard titanium-based implants. The investigated 3Y-TZP sintered ceramics presented high densification (> 99%), with a microstructure formed by submicron equiaxed tetragonal zirconia grains. The 3Y-TZP average bending strength obtained from piston-on-three-balls testing is 1192 ± 99 MPa. For both dental implant geometries, the zirconia implants showed average strength of less than 550 MPa, which, in turn, is independent of the masticatory load value or orientation angle. All finite element predictions are 50% inferior to the corresponding measured flexural strength values and preliminarily enable the 3Y-TZP ceramics for dental implant applications without fracture risk.

Este estudo teve como objetivo avaliar a influência da assimetria durante o processo de laminação com reduções de 10% e 20% na espessura empregada à liga de magnésio AZ31, do ponto de vista microestrutural e propriedade mecânica. Diversos estudos têm sido realizados nas ligas de magnésio visando adquirir melhores propriedades mecânicas, sobretudo conformabilidade, pois esta é uma das principais limitações encontradas na liga. Neste trabalho são apresentados os resultados microestruturais e mecânicos para amostras processadas por laminação simétrica e assimétrica nas reduções de 10% e 20% nas temperaturas ambiente, 100 °C, 200 °C, 300 °C e 400 °C. Foi observado que todas as amostras submetidas ao processo de laminação assimétrica apresentaram um valor maior de dureza em relação àquelas laminadas simetricamente. Também, observou-se que as amostras laminadas a 400°C apresentaram grãos refinados, podendo ser um indício de que tenha ocorrido a recristalização. Uma vez que este efeito também pôde ser observado a 300 °C, porém exclusivamente para a amostra laminada assimetricamente, este resultado pode estar relacionado ao processo assimétrico promover uma maior deformação no material.

Potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and microstructure characterization were performed on directionally solidified samples of the Al–3Cu–2Si alloy in order to study their corrosion behavior in a 0.2 M HCl electrolyte. Corrosion resistance of the investigated samples was correlated with solidification parameters, such as growth (VL), cooling rates (TR) and secondary dendritic spacing (λ2). Optical microscopy was used to characterize both the as-cast and corroded microstructures. For an immersion time of 24 hours in acidic solution, optical micrographs indicated that Si addition to Al-3Cu alloy promoted a significant decrease in the average fractions of α-Al phase increasing anodic activity of the Al-3Cu-2Si alloy. Using Tafel extrapolation, it is shown that the secondary dendritic arm spacing (λ2) acts as a factor influencing the corrosion current density (Icorr). All the EIS diagrams reveal a unique capacitive time constant and the size of the semi-circle decreases with increasing the time of immersion. Nyquist plots demonstrate that higher λ2 values cause a decrease in resistance of polarization, indicating the presence of a very thin film of aluminum oxide associated with a lower corrosion resistance.

In this work, the plastic behavior of an interstitial-free steel sheet was first evaluated by standard uniaxial tensile and hydraulic bulge tests to reproduce the intermediate and high straining levels commonly observed in sheet metal forming processes. Next, a simple procedure was proposed to obtain an equivalent work-hardening curve, representing the high strain domain instead of the conventional uniaxial tensile data. This procedure involves an anisotropy parameter calculated based on Hill's quadratic criterion using the measured r-values in the rolling and transverse sheet directions. Under the assumption of an isotropic work-hardening, the equivalent curve is defined from the true stress and true thickness plastic-strain results of the hydraulic bulge test. The transformed data were fitted to usual power-law type equations to obtain an adequate work-hardening description for finite element numerical simulation purposes. Based on the goodness-of-fit measures, namely, R-squared, root-mean-square error, and root-mean-square of residual percentage, the combined Swift–Hockett–Sherby equation has proved to be the most suitable choice to describe the plastic behavior of the investigated interstitial-free steel under both intermediate and high strains conditions.

Reducing pollutant emissions and improving safety standards are primary targets for modern mobility improvement. To meet these needs, the development of low-density steels containing aluminum is a new frontier of research for automotive applications. Low-density Fe-Mn-Al-C alloys are promising. In this regard, an alloy with high aluminum content and niobium addition belonging to the Fe-Mn-Al-C system was evaluated to understand the possible phase transformations and thus obtain a transformation diagram by continuous cooling to help future processing. Dilatometry tests were performed in a Gleeble thermomechanical simulator with different cooling rates (1, 3, 5, 10, 15, 20, 30, and 50 °C/s). Chemical analyses carried out simultaneously with dilatometry tests showed the presence of proeutectoid ferrite (αp), δ-ferrite, retained austenite, and niobium carbide (NbC). In the case of low cooling rates (1 and 3 °C/s), lamellar colonies of the eutectoid microconstituents were observed with a combination of α-ferrite and k-carbide. For higher cooling rates (5 to 50 °C/s), martensite was observed with body-centered cubic (BCC) and body-centered tetragonal (BCT) structures.

The present study aimed to evaluate insecticide toxicity to Doru luteipes (Scudder), a major predator of corn pests. Lethal (reduction in survival) and sublethal effects (prey consumption, adult tibia length and walking distance) of compounds were assessed on earwig nymphs and adults. Insects were exposed to the compounds through contact (exposure to insecticide residue on corn leaves) and ingestion (consumption of insecticide-treated prey) routes. Tested insecticides included a biopesticide (Spodoptera frugiperda multiple nucleopolyhedrovirus - SfMNPV), and modern (flubendiamide and metaflumizone) and older neurotoxins (imidacloprid + β-cyfluthrin). The imidacloprid/β-cyfluthrin mix was highly toxic (100% mortality) to the predator, regardless of the exposure route and predator stage. Metaflumizone caused mortality superior to 95% and 45% of nymphs and adults, respectively. Flubendiamide and SfMNPV were the least toxic compounds, not differing from the untreated control in any of the assessed endpoints. Adult tibial length did not differ among treatments. Overall, the insecticides caused a more pronounced effect on D. luteipes nymphs than on adults and were more toxic by the contact route. From these findings, flubendiamide and SfMNPV are safer for D. luteipes and should head insecticide choice in integrated pest management programs in corn.

Agriculture depends on the correct use of different methods for pest control, however the cultivation methods adopted for Solanaceae demands numerous pesticide applications. These products can be either harmful or selective to beneficial organisms, such as Coccinellidae predators. The aim of this study was to assess the physiological selectivity of insecticides, registered for tomato pest control, on Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae). The maximum recommended field dosage of the insecticides spinetoram, spiromesifen, methoxyfenozide, metaflumizone, tebufenozide and methomyl was used. They were sprayed on eggs, third instar larvae, pupae and adults of H. axyridis using Potter´s tower; control treatment consisted of water. Methoxyfenozide didn't reduce any biological feature of the predator. Spiromesifen only reduced survival over time when sprayed on third instar larvae. Spinetoram shortened larval period and reduced survival of adults. When sprayed on larvae, metaflumizone reduced larval survival. Tebufenozide reduced egg viability, pupal period and larval survival over time. It is concluded that methoxyfenozide, spiromesifen and spinetoram are the least toxic to H. axyridis, and their usage should be prioritized in integrated pest management (IPM) programs; both tebufenozide and metaflumizone are harmful to some important biological features of the predator. Methomyl is highly toxic in controlled conditions, so its toxicity to H. axyridis should be confirmed in field and greenhouse tests, we also suggest further studies with the other compounds in different concentration and route of exposure.

Electrochemical corrosion tests were performed on samples of horizontally solidified Al7Si0.3Mg (wt%) alloy. The investigated solidification and corrosion parameters were growth and cooling rates (VL and TR, respectively), secondary dendritic spacing (λ2), corrosion potential, and corrosion current (ECORR and iCORR, respectively). Optical and scanning electron microscopy analysis were carried out on the samples, and typical solidification microstructure was characterized by primary and eutectic phases (Alα and Alα-eutectic+ Si+ π-Al8Mg3FeSi6+θ-Mg2Si, respectively). The results depicted a higher corrosion resistance in as-cast samples with finer dendritic microstructure, that is, for higher and lower VL/TR and λ2 values, respectively. A mathematical expression characterized the iCORR variation with VL, TR, and λ2. SEM/EDS element maps and point microanalysis showed a strong decreased of Mg and Fe elements within the interdendritic regions due to the corrosion of π and θ intermetallic phases. It was allowed to conclude that Si particles exhibit cathodic behavior in relation to the matrix as well as π and θ intermetallic compounds. A comparative analysis with the literature was also conducted.

Precipitation of the intermetallic phases embrittles duplex stainless steels. Currently, most studies in this subject simulated aging phenomena by first holding the material at different isothermal conditions and then, quenching down under high cooling rates to investigate the subsequent microstructures and mechanical properties. In this work, specimens of the duplex stainless steel UNS S31803 were submitted to cooling cycles at controlled rates under non-isothermal conditions. The volume fraction of sigma and chi formed was less than 1%. The value was lower than that assumed by the Sieurin and Sandstrom model. We relate this to the initial DSS morphology, with austenite islands in a ferritic matrix. Here, the number of nucleation sites for the deleterious phases is smaller than the lamellar microstructure of ferrite and austenite usually found in duplex stainless steels.

Coffee is of great socio-economic importance, and in this scenario Brazil stands out as the largest producer and exporter of coffee beans. However, the coffee tree is susceptible to the attack of several insect pestshe main ones being the berry borer and leaf miner. However, other insects may be present in the crop, and their identification is important for the elaboration of mitigation measures. To date, the presence of the leafhopper Aethalion reticulatum (Linnaeus, 1767) (Hemiptera: Aethalionidae) in Coffea arabica (Linnaeus, 1753) (Rubiaceae) plants has not been reported in the literature. Thus, the present study aimed to describe the occurrence of A. reticulatum in arabica coffee plants on the Campus of the Universidade Federal de Lavras (UFLA), Lavras, Minas Gerais, Brazil. Key words: Fruit leafhopper; Insect pest; Coffee crop; Infestation.

Introgression of genetic material from species of the insect bacteria Wolbachia into populations of Aedes aegypti mosquitoes has been shown in randomised and non-randomised trials to reduce the incidence of dengue; however, evidence for the real-world effectiveness of large-scale deployments of Wolbachia-infected mosquitoes for arboviral disease control in endemic settings is still scarce. A large Wolbachia (wMel strain) release programme was implemented in 2017 in Rio de Janeiro, Brazil. We aimed to assess the effect of this programme on the incidence of dengue and chikungunya in the city.67 million wMel-infected mosquitoes were released across 28 489 locations over an area of 86·8 kmsup2/supin Rio de Janeiro between Aug 29, 2017 and Dec 27, 2019. Following releases, mosquitoes were trapped and the presence of wMel was recorded. In this spatiotemporal modelling study, we assessed the effect of the release programme on the incidence of dengue and chikungunya. We used spatiotemporally explicit mathematical models applied to geocoded dengue cases (N=283 270) from 2010 to 2019 and chikungunya cases (N=57 705) from 2016 to 2019.On average, 32% of mosquitoes collected from the release zones between 1 month and 29 months after the initial release tested positive for wMel. Reduced wMel introgression occurred in locations and seasonal periods in which cases of dengue and chikungunya were historically high, with a decrease to 25% of mosquitoes testing positive for wMel during months in which disease incidence was at its highest. Despite incomplete introgression, we found that the releases were associated with a 38% (95% CI 32-44) reduction in the incidence of dengue and a 10% (4-16) reduction in the incidence of chikungunya.Stable establishment of wMel in the geographically diverse, urban setting of Rio de Janeiro seems to be more complicated than has been observed elsewhere. However, even intermediate levels of wMel seem to reduce the incidence of disease caused by two arboviruses. These findings will help to guide future release programmes.Billamp; Melinda Gates Foundation and the European Research Council.

Introgression of the insect bacterium Wolbachia into Aedes aegypti mosquito populations has been shown in randomised and non-randomised trials to reduce the incidence of dengue, however evidence for the real-world effectiveness of large-scale Wolbachia mosquito deployments for arboviral disease control in endemic settings is still limited. A large Wolbachia (wMel strain) program was implemented in 2017 in Rio de Janeiro, Brazil. Here we assess the impact of the release program on dengue and chikungunya incidence., This study was funded by the ERC (grant n. 804744) and the Bill and Melinda Gates Foundation.