Mechanical properties of fly ash geopolymers containing steelmaking ladle slag

The effect of adding steelmaking ladle slag to fly ash based geopolymers has been studied. For that, flexural and compression strengths were evaluated at 7 and 28 days after curing. It can be concluded that the increase in fly ash content has a relevant effect on the various mechanical properties.W2V, SA, Geodesigninfo:eu-repo/semantics/publishedVersio

Fracture behavior in geopolymer mixtures including fly ash and various industrial waste

The fracture resistance behavior of fly ash based geopolymer mixtures incorporating different types of industrial wastes has been investigated. Therefore, 4 different geopolymer mixtures were analyzed, with the intent to retrieve information about their Initial Flexural Stiffness (Ri), and Ultimate Load (Pu). A result analysis revealed that one type of mixture was considerably superior to the rest in terms of Initial Flexural Stiffness and Ultimate Load.W2V, SA, Geodesigninfo:eu-repo/semantics/publishedVersio

O Professor da Educação Básica e as Tecnologias Digitais no Ensino Remoto

This article aims to analyze the perception of elementary school teachers about their practices and remote teaching, which was implemented in an emergency due to the Covid-19 pandemic. It is a survey, in which 46 teachers participated when answering a form with 17 closed questions and an open one about this experience, the digital technologies used, the difficulties in this implementation, the access to the internet, among others. The participants identified messaging applications (WhatsApp and Telegram) as the most used tools in class, being considered the easiest, and the posture of permanent learners was observed in them.   Keywords: Elementary school. Digital technologies. Emergency remote teaching. COVID-19 pandemic.Este artigo se propõe a analisar a percepção de professores da Educação Básica sobre as suas práticas e o ensino remoto, implantado de forma emergencial devido à pandemia da Covid-19. Trata-se de um levantamento, do qual participaram 46 professores que responderam um formulário com 17 perguntas fechadas e uma aberta sobre essa experiência, as tecnologias digitais utilizadas, as dificuldades nessa implementação, o acesso a internet, entre outros. As participantes identificaram os aplicativos de mensagem (WhatsApp e Telegram) como as ferramentas mais utilizadas nas aulas, sendo consideradas as mais fáceis. Observou-se neles a postura de permanentes aprendizes.   Palavras-chave:Educação básica. Tecnologias digitais. Ensino remoto emergencial. Pandemia Covid-19

Microplastics in the Olfactory Bulb of the Human Brain

Importance Microplastic (MP) pollution is an emerging environmental and health concern. While MPs have been detected in various human tissues, their presence in the human brain has not been documented, raising important questions about potential neurotoxic effects and the mechanisms by which MPs might reach brain tissues. Objective To determine the presence of MPs in the human olfactory bulb and to analyze their characteristics such as size, morphology, color, and polymeric composition. Design, Setting, and Participants This case series study used a cross-sectional design involving the analysis of olfactory bulb tissues obtained from deceased individuals during routine coroner autopsies. The sampling procedures were conducted at São Paulo City Death Verification Service, with laboratory analysis carried out at the Brazilian Synchrotron Light Laboratory (LNLS). Participants included 15 adult individuals who had been residents of São Paulo for more than 5 years and underwent coroner autopsies. Exclusion criteria included previous neurosurgical interventions. Data analysis was performed in April 2024. Exposure The primary exposure assessed was the presence of MPs in the olfactory bulb, analyzed through direct tissue examination and digested tissue filtration followed by micro-Fourier transform infrared spectroscopy. Main Outcomes and Measures The main outcomes were the identification and characterization of MPs within the olfactory bulb, including their size, morphology, color, and polymeric composition. Results The median age of the 15 deceased individuals was 69.5 years, ranging from 33 to 100 years, with 12 males and 3 females. MPs were detected in the olfactory bulbs of 8 out of 15 individuals. A total of 16 synthetic polymer particles and fibers were identified, with 75% being particles and 25% being fibers. The most common polymer detected was polypropylene (43.8%). Sizes of MPs ranged from 5.5 μm to 26.4 μm for particles, and the mean fiber length was 21.4 μm. Polymeric materials were absent in procedural blank and negative control filters, indicating minimal contamination risk. Conclusions and Relevance This case series provides evidence of MPs found in the human olfactory bulb, suggesting a potential pathway for the translocation of MPs to the brain. The findings underscore the need for further research on the health implications of MP exposure, particularly concerning neurotoxicity and the potential for MPs to bypass the blood-brain barrier

Quantificação do teor de metais em águas engarrafadas comercializadas no município de Belém através de espectrometria de emissão ótica / Quantification of metal content in bottled waters commercialized in the municipality of Belém through spectrometry of optical emission

Nos últimos anos tem sido verificado um crescimento considerável no consumo de águas engarrafadas no Brasil, aumentando de 0,3 para 18,5 L per capita/ano. Para atender essa demanda, as indústrias aumentaram a produção, novas empresas surgiram e, consequentemente, surge a necessidade do monitoramento da qualidade dessas águas no mercado. O objetivo deste trabalho foi a quantificação do teor de metais em águas engarrafadas, de cinco marcas comercializadas em supermercados na cidade de Belém-PA. Foram utilizadas 120 (cento e vinte) amostras provenientes de oito locais da cidade. A determinação de metais foi feita utilizando um ICP-OES modelo VISTA PRO.  Os resultados obtidos foram comparados com os valores máximos permitidos (VMP) de acordo com a Portaria de Consolidação N°5/17 do Ministério da Saúde. Os teores médios de Al, Fe, Na e Ba estiveram abaixo do máximo permitido na referida Portaria (0,2 mg/L e 0,7 mg/L, respectivamente) não apresentando, portanto, nenhum tipo de contaminação por metais tóxicos. Os metais mais abundantes foram: Na (1,7594 mg/L), Mg (0,3156 mg/L), K (0,2756 mg/L) e Ca (0,1644 mg/L). estando apenas uma amostra com teor de bário fora dos padrões da referida Portaria, indicando uma provável contaminação pontual durante a captação, envase ou devido à possível adição de sais de bário nessas águas

Estatística multivariada aplicada na avaliação dos parâmetros químicos e físico-químicos da água engarrafada do município de Belém-PA / Multivariate statistics applied in the evaluation of chemical and physical-chemical parameters of bottled water in the municipality of Belém-PA

A estatística multivariada fornece ferramentas importantes no entendimento do comportamento de variáveis físico-químicas e químicas, permitindo traçar padrões de comportamento para diversas matrizes ambientais, como é o caso de águas minerais. Este trabalho teve por objetivo utilizar a estatística multivariada na avaliação de parâmetros químicos e físico-químicos em amostras de água engarrafada comercializada no município de Belém. Foram utilizados softwares de modelagem estatística, como os programas Statistica, Minitab 14 e Microsoft Excel para análise de correlação, Box Plot, ANOVA Fator Único, Análise de Agrupamentos Hierárquicos (HCA) e Análise das Componentes Principais (PCA). Os resultados mostraram que a maioria dos elementos químicos e variáveis físico-químicas se apresentou dentro da conformidade com a legislação e sem variações significativas. Os metais em maiores concentrações nas águas minerais tendem a possuir comportamentos semelhantes, como é o caso do K, Mg, Na, Ba e Ca. Os testes de PCA mostraram que a maioria das amostras avaliadas não se comportam de maneira semelhante, apresentando ainda como variáveis mais significativas salinidade, condutividade, Ba, Ca, K e Na, Al e Be. Concluiu-se que a estatística multivariada pode ser usada como instrumento na avaliação do comportamento de parâmetros químicos e físico-químicos das águas engarrafadas

Birds of the Pantanal floodplains, Brazil: historical data, diversity, and conservation

The Pantanal floodplains of Brazil are a region of rich biodiversity. To date, the true richness of the Pantanal avifauna has not been explored satisfactorily caused by a lack of studies in the region and, especially, by the divergence of opinion among the works published by various authors on the many species found in the region. This is due to the lack of criteria in examining records, both with regard to the reliability of the identifications and in the precise geographical allocation. Therefore, in the study, we collage findings from various studies and records created by us in the last few decades from 199 distinct locations to produce a list of birds in the Pantanal floodplains. We grouped the results into three lists: primary, secondary, and tertiary. We found that the avifauna of the Pantanal floodplain is composed of a total of 617 species, of which 571 (92%) have supporting records of occurrence (primary list) and 46 still lack documentation (secondary list). The number of species listed here for the Pantanal floodplain represents 32% of all avifauna known to the Brazilian territory. This reflects the importance of the biome, as part of the national territory, for the maintenance of a meaningful avifaunistic richness. Migratory birds (n = 183), notably northern ones (n = 43), are among the main players involved in ecological processes of nutrient cycling and dispersion of important pathogens between the two continents. With regard to conservation, 25 species are included in some category of threat in the lists of threatened species with global extinction. We hope that our list will help future researchers a more definitive approach when researching the avian fauna in this bountiful region

Checklist of the birds of Mato Grosso do Sul state, Brazil: diversity and conservation

Several phytogeographic regions (Cerrado, Pantanal, Atlantic Forest, Gran Chaco, and Chiquitano Dry Forests) converge in the state of Mato Grosso do Sul, Brazil, and influence regional biodiversity. Despite a list of birds in the state of Mato Grosso do Sul being published by Nunes et al. (2017), it is necessary to update and critically review avifauna records. In this study, we gathered the results of several records obtained from species lists and online data platforms of the 336 sites in this state over the last decades and grouped them into Main (Primary and Secondary) and Tertiary Lists. The avifauna of Mato Grosso do Sul is composed of 678 species, of which 643 (95%) have records proving their occurrence (Primary List), whereas 34 still lack documentation (Secondary List). The number of related species for Mato Grosso do Sul represents 34% of the Brazilian avifauna. Some species stand out for their unique occurrence in Mato Grosso do Sul, such as Melanerpes cactorum, Celeus lugubris, Phaethornis subochraceus, and Cantorchilus guarayanus, reflecting the influence of different phytogeographic regions of the Chaco and Chiquitano Dry Forests. Migrants represent 20% of the bird community occurring in the state, of which 93 species correspond to migrants from various regions of South America (south and west) and 40 to boreal migrants. Thirty-three species perform nomadic movements across the Pantanal Plain and other regions of the state. Thirty-one species are included in some conservation-threatened categories of global and/or national endangered species lists. Other 30 species are included in the near-threatened category at the global level and 23 at the national level. In addition, species typical of dry forests (in Serra da Bodoquena and Maciço do Urucum) and those from the Atlantic Forest in the south of the state deserve attention due to their restricted distribution and the high anthropogenic pressure on their habitat

Checklist of the birds of Mato Grosso do Sul state, Brazil: diversity and conservation

Several phytogeographic regions (Cerrado, Pantanal, Atlantic Forest, Gran Chaco, and Chiquitano Dry Forests) converge in the state of Mato Grosso do Sul, Brazil, and influence regional biodiversity. Despite a list of birds in the state of Mato Grosso do Sul being published by Nunes et al. (2017), it is necessary to update and critically review avifauna records. In this study, we gathered the results of several records obtained from species lists and online data platforms of the 336 sites in this state over the last decades and grouped them into Main (Primary and Secondary) and Tertiary Lists. The avifauna of Mato Grosso do Sul is composed of 678 species, of which 643 (95%) have records proving their occurrence (Primary List), whereas 34 still lack documentation (Secondary List). The number of related species for Mato Grosso do Sul represents 34% of the Brazilian avifauna. Some species stand out for their unique occurrence in Mato Grosso do Sul, such as Melanerpes cactorum, Celeus lugubris, Phaethornis subochraceus, and Cantorchilus guarayanus, reflecting the influence of different phytogeographic regions of the Chaco and Chiquitano Dry Forests. Migrants represent 20% of the bird community occurring in the state, of which 93 species correspond to migrants from various regions of South America (south and west) and 40 to boreal migrants. Thirty-three species perform nomadic movements across the Pantanal Plain and other regions of the state. Thirty-one species are included in some conservation-threatened categories of global and/or national endangered species lists. Other 30 species are included in the near-threatened category at the global level and 23 at the national level. In addition, species typical of dry forests (in Serra da Bodoquena and Maciço do Urucum) and those from the Atlantic Forest in the south of the state deserve attention due to their restricted distribution and the high anthropogenic pressure on their habitat