Pandemia de COVID-19: o olhar da população em relação às medidas preventivas

The aim of the study was to understand the population's perception of preventive measures to contain the transmission of the new coronavirus. Cross-sectional, exploratory, and descriptive study, with a quantitative approach, of non-probabilistic sampling. The research subjects were users of the social networks Facebook, Instagram, and WhatsApp. An online form was used with sociodemographic and specific questions about this study. It was found that most participants support physical distance as necessary to control the COVID-19 pandemic, however, when it involves individual practices, it was observed that there is a divergence with the previous discourse. More in-depth studies are needed to better understand the factors involved in citizens' adherence or not to the measures imposed by health and government authorities and thus, they may be more assertive in the proposed measures.O objetivo do estudo foi compreender a percepção da população sobre as medidas preventivas para conter a transmissão do novo coronavírus. Estudo transversal, exploratório e descritivo, com abordagem quantitativa, de amostragem não probabilística. Os sujeitos da pesquisa foram usuários das redes sociais Facebook, Instagram e WhatsApp. Foi utilizado um formulário online com questões sociodemográficas e específicas sobre o tema deste estudo. Verificou-se que a maioria dos participantes apoiam o distanciamento físico como necessário para controle da pandemia de COVID-19, porém, quando envolve práticas individuais, observou-se que há divergência com o discurso anterior. Estudos mais aprofundados são necessários no sentido de compreender melhor os fatores envolvidos na adesão ou não dos cidadãos às medidas impostas pelas autoridades sanitárias e governamentais e assim, poderão ser mais assertivos nas medidas propostas

Intermittent in-situ high-resolution X-ray microscopy of 400-nm porous glass under uniaxial compression: study of pore changes and crack formation

The properties of porous glasses and their field of application strongly depend on the characteristics of the void space. Understanding the relationship between their porous structure and failure behaviour can contribute to the development of porous glasses with long-term reliability optimized for specific applications. In the present work, we used X-ray computed tomography with nanometric resolution (nano-CT) to image a controlled pore glass (CPG) with 400 nm-sized pores whilst undergoing uniaxial compression in-situ to emulate a stress process. Our results show that in-situ nano-CT provides an ideal platform for identifying the mechanisms of damage within glass with pores of 400 nm, as it allowed the tracking of the pores and struts change of shape during compression until specimen failure. We have also applied computational tools to quantify the microstructural changes within the CPG sample by mapping the displacements and strain fields, and to numerically simulate the behaviour of the CPG using a Fast Fourier Transform/phase-field method. Both experimental and numerical data show local shear deformation, organized along bands, consistent with the appearance and propagation of +/- 45 degrees cracks.Comment: 14 pages, 6 figure

Bioactive glass–ceramics containing fluorapatite, xonotlite, cuspidine and wollastonite form apatite faster than their corresponding glasses

Crystallisation of bioactive glasses has been claimed to negatively affect the ion release from bioactive glasses. Here, we compare ion release and mineralisation in Tris–HCl buffer solution for a series of glass–ceramics and their parent glasses in the system SiO2–CaO–P2O5–CaF2. Time-resolved X-ray diffraction analysis of glass–ceramic degradation, including quantification of crystal fractions by full pattern refinement, show that the glass–ceramics precipitated apatite faster than the corresponding glasses, in agreement with faster ion release from the glass–ceramics. Imaging by transmission electron microscopy and X-ray nano-computed tomography suggest that this accelerated degradation may be caused by the presence of nano-sized channels along the internal crystal/glassy matrix interfaces. In addition, the presence of crystalline fluorapatite in the glass–ceramics facilitated apatite nucleation and crystallisation during immersion. These results suggest that the popular view of bioactive glass crystallisation being a disadvantage for degradation, apatite formation and, subsequently, bioactivity may depend on the actual system study and, thus, has to be reconsidered

Porous polymeric microparticles foamed with supercritical CO₂ as scattering white pigments

Nowadays, titanium dioxide (TiO2) is the most commercially relevant white pigment. Nonetheless, it is widely criticized due to its energy-intensive extraction and costly disposal of harmful by-products. Furthermore, recent studies discuss its potential harm for the environment and the human health. Environment-friendly strategies for the replacement of TiO2 as a white pigment can be inspired from nature. Here whiteness often originates from broadband light scattering air cavities embedded in materials with refractive indices much lower than that of TiO2. Such natural prototypes can be mimicked by introducing air-filled nano-scale cavities into commonly used polymers. Here, we demonstrate the foaming of initially transparent poly(methyl methacrylate) (PMMA) microspheres with non-toxic, inert, supercritical CO2. The properties of the foamed, white polymeric pigments with light scattering nano-pores are evaluated as possible replacement for TiO2 pigments. For that, the inner foam structure of the particles was imaged by phase-contrast x-ray nano-computed tomography (nano-CT), the optical properties were evaluated via spectroscopic measurements, and the mechanical stability was examined by micro compression experiments. Adding a diffusion barrier surrounding the PMMA particles during foaming allows to extend the foaming process towards smaller particles. Finally, we present a basic white paint prototype as exemplary application

Nano-imaging confirms improved apatite precipitation for high phosphate/silicate ratio bioactive glasses

Bioactive glasses convert to a biomimetic apatite when in contact with physiological solutions; however, the number and type of phases precipitating depends on glass composition and reactivity. This process is typically followed by X-ray diffraction and infrared spectroscopy. Here, we visualise surface mineralisation in a series of sodium-free bioactive glasses, using transmission electron microscopy (TEM) with energy-dispersive X-ray spectroscopy (EDXS) and X-ray nano-computed tomography (nano-CT). In the glasses, the phosphate content was increased while adding stoichiometric amounts of calcium to maintain phosphate in an orthophosphate environment in the glass. Calcium fluoride was added to keep the melting temperature low. TEM brought to light the presence of phosphate clustering and nearly crystalline calcium fluoride environments in the glasses. A combination of analytical methods, including solid-state NMR, shows how with increasing phosphate content in the glass, precipitation of calcium fluoride during immersion is superseded by fluorapatite precipitation. Nano-CT gives insight into bioactive glass particle morphology after immersion, while TEM illustrates how compositional changes in the glass affect microstructure at a sub-micron to nanometre-level

Functional properties of milk drinks flavored with mangaba pulp and enriched with passion fruit bark flour

Dairy foods including dairy based drinks play an important role in human nutrition. The flour of the passion fruit peel has high potential for use in the enrichment dairy drinks improving the nutritional and technological qualities besides an alternative to reduce waste by-products in the food industry. Thus, this study aimed to evaluate the physical and chemical parameters, texture, color, chemical composition, scanning electron microscopy (SEM), phenolic compounds, antioxidant, viability of lactic bacteria and sensory profile of milk drinks added mangaba pulp and passion fruit peel flour of the (FPFP). Four milk drinks formulations were processed with concentrations of 5; 10; 15 and 20% mangaba pulp and 1% of passion fruit peel flour. The dairy beverages showed results physical and chemical, microbiological and sensory consistent with those described in the literature and as expected, with a high sensory acceptability of milk drinks with increased by 10% mangaba pulp.Keywords: Color, fermented milk, scanning electron microscopy (SEM), viabilit

Avanços na abordagem terapêutica da insuficiência cardíaca com fração de ejeção preservada (ICFEP): O uso de inibidores de SGLT-2

A insuficiência cardíaca (IC) com fração de ejeção preservada (ICFEP) é a forma mais prevalente de IC em pacientes com mais de 65 anos e representa mais de 50% dos casos prevalentes de IC na população. As intervenções terapêuticas da ICFEP ainda estão sendo exploradas e pesquisadas, como o uso de inibidores de SGLT-2. O presente estudo de revisão buscou avaliar novos avanços na abordagem terapêutica da insuficiência cardíaca com fração de ejeção preservada (ICFEP) a partir do uso de inibidores de SGLT-2, documentados por meio de estudos clínicos e randomizados. Trata-se de uma pesquisa de revisão integrativa realizada por meio da base de dados PubMed, que levou em consideração os seguintes critérios de inclusão: ensaios clínicos e testes controlados e aleatórios; artigos publicados no último ano; que possuíam texto completo disponível e que abordassem acerca do uso de inibidores de SGLT-2 na ICFEP. Ficou constatado que a dapagliflozina resultou em melhora dos sintomas relacionados à insuficiência cardíaca e limitações físicas nesses pacientes, bem como a canagliflozina, a qual trouxe resultados de melhora rápida e clinicamente significativa dos sintomas de IC. Já a empagliflozina demonstrou uma redução significativa no risco de morte cardiovascular ou hospitalizações por insuficiência cardíaca. Por fim, verificou-se que a ipragliflozina pode contribuir, em determinados subgrupos, reduzindo o índice de massa ventricular esquerda e, ainda, uma redução dos níveis de NT-proBNP, um marcador de disfunção ventricular. Dessa forma, os inibidores de SGLT-2 se fazem importantes medicações para a terapêutica efetiva da ICFEP atualmente

O que há de novo no tratamento da endocardite infecciosa: uma revisão integrativa

A endocardite infecciosa (EI) é uma doença rara que ainda possui um impacto significativo. Estima-se que a doença afete 3 a 10 pessoas em cada 10.000 por ano na população em geral, com estimativas que estão aumentando com o passar dos anos. O presente estudo de revisão buscou avaliar novos avanços e atualizações na abordagem terapêutica da endocardite infecciosa, documentados por meio de estudos clínicos e randomizados. Trata-se de uma pesquisa de revisão integrativa realizada por meio da base de dados PubMed, que levou em consideração os seguintes critérios de inclusão: ensaios clínicos e testes controlados e aleatórios; artigos publicados nos últimos três anos; que possuíam texto completo disponível e que abordassem acerca da terapêutica da endocardite infecciosa. Ficou constatado que pacientes submetidos à terapia de hemoadsorção de citocinas durante a circulação extracorpórea acumularam uma dose de norepinefrina menor que a metade nos momentos do pós-operatório. Além disso, a terapia combinada de daptomicina e fosfomicina foi associada com menor falha microbiológica e menor bacteremia complicada, apesar de apresentar maior ocorrência de eventos adversos que os pacientes que receberam apenas daptomicina em monoterapia. Por fim, é vista a importância de terapias imunomoduladoras, visto que a redução de mediadores imunológicos possuem a capacidade de restaurar a imunocompetência funcional dos indivíduos afetados

Rarity of monodominance in hyperdiverse Amazonian forests.

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors