25 research outputs found

    Micromesoporous Activated Carbons as Catalysts for the Efficient Oxidation of Aqueous Sulfide

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    KOH activation of a mesophase pitch produces very efficient carbons for the removal of sulfide in aqueous solution, increasing the sulfur oxidation rate with the degree of activation of the carbon. These carbons are characterized by their graphitic structures, with domains of sizes of around 20 nm, and a moderate concentration of surface oxygen groups (0.2–0.5 mmol·g–1) dominating the basic groups. Because the activation leads first to a strong development of the micropores and later to a development of the mesopores, the surface area values are always high, reaching values of as high as 3250 m2·g–1 in the most activated carbon, with a volume of mesopores of as high as 44% of the total pore volume. In the presence of this carbon, the sulfide oxidation rate is 100 times higher than that found for a commercial activated carbon, the results indicating that the porosity of the carbon, especially mesoporosity, plays a role more important than the structure or the chemical nature of the carbon in the kinetics of sulfide oxidation to different polysulfides.The authors thank CNPq, CAPES, INCT, PRPq-UFMG, and Prometeo II/2014/004 for financial support

    ENTRE NARRATIVAS LITERÁRIAS E HISTÓRICAS: CONFLUÊNCIAS ENTRE O LIVRO DIDÁTICO DE HISTÓRIA E A LITERATURA

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    Este trabalho constitui-se de uma reflexão sobre umas das atividades didático-pedagógicas desenvolvidas pelo subprojeto A Formação da Consciência Histórica: articulações entre metodologia e prática no ensino de História, elaborado por um coletivo de professores do Curso de História da Faculdade de Filosofia Dom Aureliano Matos (FAFIDAM), campus da Universidade Estadual do Ceará (UECE) em Limoeiro do Norte na Escola de Ensino Médio Arsênio Ferreira Maia no ano de 2017, explorando as relações entre o livro didático de História e a Literatura reforçando a dimensão educativa da biblioteca escolar e as possibilidades de utilização de seu acervo

    COVID-19 outcomes in people living with HIV: Peering through the waves

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    Objective: To evaluate clinical characteristics and outcomes of COVID-19 patients infected with HIV, and to compare with a paired sample without HIV infection. Methods: This is a substudy of a Brazilian multicentric cohort that comprised two periods (2020 and 2021). Data was obtained through the retrospective review of medical records. Primary outcomes were admission to the intensive care unit, invasive mechanical ventilation, and death. Patients with HIV and controls were matched for age, sex, number of comorbidities, and hospital of origin using the technique of propensity score matching (up to 4:1). They were compared using the Chi-Square or Fisher's Exact tests for categorical variables and the Wilcoxon for numerical variables. Results: Throughout the study, 17,101 COVID-19 patients were hospitalized, and 130 (0.76%) of those were infected with HIV. The median age was 54 (IQR: 43.0;64.0) years in 2020 and 53 (IQR: 46.0;63.5) years in 2021, with a predominance of females in both periods. People Living with HIV (PLHIV) and their controls showed similar prevalence for admission to the ICU and invasive mechanical ventilation requirement in the two periods, with no significant differences. In 2020, in-hospital mortality was higher in the PLHIV compared to the controls (27.9% vs. 17.7%; p = 0.049), but there was no difference in mortality between groups in 2021 (25.0% vs. 25.1%; p > 0.999). Conclusions: Our results reiterate that PLHIV were at higher risk of COVID-19 mortality in the early stages of the pandemic, however, this finding did not sustain in 2021, when the mortality rate is similar to the control group

    Uso de telas pela população pediátrica e seus impactos oftalmológicos a curto e a longo prazo: uma revisão sistemática : Use of screens by the pediatric population and its short and long-term ophthalmological impacts: a systematic review

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    Ao se discorrer sobre a formação e formatação da nossa sociedade, pode-se notar que cada vez mais esta está permeada pela tecnologia e pelos sistemas integrativos, processo esse benéfico para comunicação, gestão e tomada de decisões para além de ser uma ferramenta de trabalho e entretenimento, porém, com a progressiva quantidade de horas que ficamos expostos a este tipo de tecnologia também podem acarretar prejuízos a acuidade visual dos usuários. Juntamente a isso, nota-se que as crianças estão tendo cada vez mais precocemente acesso os equipamentos eletrônicos e deixando de lado as brincadeiras, desta forma a partir de uma pesquisa qualitativa, feita a partir de um levantamento bibliográfico, pode-se dispor que esta busca compreender quais são os sintomas e efeitos do uso excessivo deste tipo de ferramenta e algumas formas de tratamento e profilaxia que podem ser dispostas sobre o tema, com enfoque na população pediátrica

    Alcoolismo em pacientes submetidos a cirurgia bariátrica: uma revisão sistemática: Alcoholism in patients undergoing bariatric surgery: a systematic review

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    A Cirurgia bariátrica tem sido uma opção de muitas pessoas que visam superar a obesidade e garantir qualidade de vida e saúde. No entanto, casos de complicações clínicas após operação tem ocorrido, sendo comum a incidência de alcoolismo. Este estudo teve como objetivo refletir sobre as causas da incidência de alcoolismo entre pacientes que foram submetidos a cirurgias bariátricas. Para o alcance dessa finalidade, realizou-se uma revisão sistemática de literatura, selecionando-se fontes das bases de dados Scielo Brasil, PubMed e Biblioteca Virtual em Saúde (BVS), publicados em língua portuguesa, nos anos de 2017 a 2022. Realizando-se a análise dos dados concluiu-se que o transtorno do uso de álcool em pessoas submetidas à cirurgia bariátrica tem sido recorrente, especialmente entre homens de baixa renda e que fizeram a cirurgia do tipo bypass gástrico. Observou-se também que o consumo de álcool é maior no pós-operatório e que boa parte dos pacientes que se submeteu a esse tipo de cirurgia ignorava o risco de desenvolver o referido transtorno. Em função disso, boa parte dos estudos que integraram esta revisão reconhece a necessidade do acompanhamento, pela equipe de saúde, dos pacientes logo após a cirurgia bariátrica e a adesão desses ao tratamento devido, visando prevenir o transtorno do uso de álcool

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

    Get PDF

    Pervasive gaps in Amazonian ecological research

    Get PDF
    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost
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