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Efeitos do tempo de armazenamento e de diferentes tipos de açúcares nas características de cor, compostos bioativos e capacidade antioxidante de geleias de jabuticaba.
No full textThe objective of this study was to evaluate the effects of storage time and the use of different sugar types (crystal, refined, demerara, brown) on color characteristics, bioactive compounds, and antioxidant capacity of jaboticaba jellies. All analyses (microbiological, color, anthocyanins, vitamin C, total phenolic compounds, and antioxidant capacity by ABTS, DPPH, and β-carotene/linoleic acid systems) were performed for 120 days. The results were evaluated by means test and Pearson correlation. It was found that the sugars used in preparation and storage influenced the characteristics of jaboticaba jellies, and mold and yeast growth remained within the standards allowed by Brazilian legislation. All jellies were darkened during storage. Bioactive compound degradation was observed, and antioxidant capacity was reduced. Positive correlations were observed. Thus, demerara sugar, even though it does not provide bright colors in jellies, is the most beneficial for the production of jaboticaba jellies, due to the presence of nutritional compounds.O objetivo deste estudo foi avaliar os efeitos do tempo de armazenamento e do uso de diferentes tipos de açúcares (cristal, refinado, demerara, mascavo) nas características de cor, compostos bioativos e capacidade antioxidante de geleias de jabuticaba. Todas as análises (microbiológicas, cor, antocianinas, vitamina C, compostos fenólicos totais e capacidade antioxidante pelos sistemas ABTS, DPPH e β-caroteno/ácido linoléico) foram realizadas durante 120 dias. Os resultados foram avaliados pelo teste de médias e correlação de Pearson. Verificou-se que os açúcares utilizados no preparo e armazenamento influenciaram nas características das geleias de jabuticaba e o crescimento de fungos e leveduras permaneceu dentro dos padrões permitidos pela legislação brasileira. Todas as geleias ficaram escurecidas durante o armazenamento. Ffoi observada degradação dos compostos bioativos e a capacidade antioxidante foi reduzida. Correlações positivas foram observadas. Assim, o açúcar demerara, mesmo não proporcionando cores vivas nas geleias, é o mais benéfico para a produção de geleias de jabuticaba, devido à presença de compostos nutricionais
Olanzapine during lactation : impact on testicular morphometry and endocrine parameters in adult wistar rats.
No full textOlanzapine (OLZ) is an antipsychotic medication used to treat postpartum psychiatric symptoms. It aimed to evaluate the effects of administering OLZ to lactating rats on testicular parameters of adult Wistar rats. Mothers received 2.5, 5 or 10 mg/ kg until weaning. Adult male rats showed decrease in body weight, weight of testes, epididymis, prostate, seminal gland and gonadosomatic index when higher doses of OLZ were administered. Testicular volumetric parameters, as well as the length of seminiferous tubules, were also reduced in animals treated with the highest doses of OLZ. The diameter of the seminiferous tubules and the height of the seminiferous epithelium were reduced. There was also a relevant decrease in the population of Sertoli cells and a relevant reduction in the volume of individual Leydig cells. Histopathological analysis of the testes showed lesions compatible with testicular degeneration in rats treated with the highest dose of OLZ. There was a significant reduction in plasma testosterone levels in all treatments. It is noted, therefore, that the adverse impact on the testes of the highest doses of the drug during the neonatal period persisted into adulthood, with the dose of 2.5 mg/kg of OLZ proving to be safer than the others
A experiência docente como recurso para a construção de saberes para ensinar com questões sociocientíficas.
No full textPrograma de Pós-Graduação em Educação. Departamento de Educação, Instituto de Ciências Humanas Sociais, Universidade Federal de Ouro Preto.Neste trabalho investigamos como as experiências profissionais mobilizadas por professores de Ciências são usadas como recurso para a construção de saberes para ensinar com QSC. A partir de um levantamento sistemático da literatura da área argumentamos sobre a importância de se estudar os saberes docentes considerando-se a sua dimensão social. Nossa inserção no campo de pesquisa como observadoras participantes nos levou a propor três questões de pesquisa: (i) qual o papel atribuído pelos professores do grupo às experiências profissionais mobilizadas por eles nas interações discursivas?; (ii) como esses professores usavam essas experiências ao longo das suas interações discursivas no curso?; e (iii) quais relações podemos estabelecer entre a mobilização das experiências profissionais e a construção de saberes para ensinar com QSC naquele contexto e em contextos mais amplos? Orientadas por uma perspectiva etnográfica e apoiadas no estudo dos domínios e temas culturais e em alguns pressupostos da abordagem microetnográfica do discurso, investigamos a participação de um grupo de treze professores de Ciências em um curso intitulado “Questões sociocientíficas na formação continuada de professores de Ciências”, desenvolvido de forma online. Todos os encontros do curso foram gravados na própria plataforma. Para a construção dos dados recorremos à uma variedade de ferramentas etnográficas, como: observação participante; anotações de campo; entrevistas individuais com os professores e análise de artefatos produzidos por eles ao longo do curso. A partir de um movimento recursivo para a análise dos dados, identificamos domínios e temas culturais associados à participação dos professores na construção discursiva de saberes para ensinar com QSC, que nos permitiram uma visão mais holística da cena cultural, ao mesmo tempo em que focamos em detalhes mais específicos desta. Além disso, utilizamos a análise microetnográfica do discurso para evidenciar como construímos aqueles domínios culturais e para fornecer evidências materiais que nos permitissem responder às nossas questões de pesquisa. Identificamos que as experiências profissionais mobilizadas pelos professores eram compostas por uma variedade de elementos, que atuavam como recursos para a construção de saberes para ensinar com QSC. Dentre estes destacam- se saberes relacionados à natureza das QSC, à sua abordagem no ensino e às dificuldades dos estudantes. Essas aprendizagens estavam relacionadas aos usos que os professores faziam de suas experiências no discurso, os quais ampliavam ou restringiam suas oportunidades de aprender naquele contexto. Além disso, nosso estudo daquele grupo de professores de Ciências nos possibilitou compreender que a incorporação (ou não) de práticas pedagógicas voltadas para o ensino com QSC depende do alinhamento destas às demandas enfrentadas na profissão. Esperamos que as compreensões que alcançamos com essa investigação possam inspirar a promoção de cursos de formação continuada que busquem desenvolver cenários profícuos para a criação e manutenção de comunidades discursivas de professores nas quais o compartilhamento de suas experiências profissionais potencialize suas aprendizagens. Além disso, considerando o caráter social, contextual e situado dos saberes docentes, sugerimos que mais pesquisas sejam realizadas na tentativa de dar visibilidades a estes aspectos pela adoção de lógicas de investigação que assumam professores em interação uns com os outros como unidade de análise.On this work we investigated how the professional experiences mobilized by Science teachers are used as resources for the construction of knowledges to teach with SSI. Coming from systematic research on the literature of this field we discussed about the importance of studying the teaching knowledges, considering their social dimension. Our insertion on the field of research as participating observers has lead us to propose three research questions: (i) what is the role attributed by the teachers of the group to the professional experiences mobilized by them in the discursive interactions?; (ii) how did these teachers use that experience throughout their discursive interactions on the course?; and (iii) what relations can we establish between the mobilization of the professional experiences and the construction of knowledges for teaching SSI on that context and in wider contexts? Oriented by an ethnographic perspective and based on the studies of the domains and cultural themes and in some premises of the microethnographic approach of the discourse we investigated the participation of a group of thirteen Science teachers in a course entitled “Socio-scientific issues on the continued formation of science teachers”, developed online. All of the courses’ meetings were recorded on the platform itself. To construct the data, we used a variety of ethnographic tools, such as: participant observation; field notes; individual interviews with teachers and analyses of artifacts produced by them throughout the course. Using a recursive movement to analyze the data, we identified cultural domains and themes associated with teachers' participation in the discursive construction of knowledge to teach with SSI, which allowed us a more holistic view of the cultural scene, while focusing more on its specific details. Furthermore, we used microethnographic discourse analysis to highlight how we constructed those cultural domains and to provide material evidence that allowed us to answer our research questions. We identified that the professional experiences mobilized by teachers were composed of a variety of elements, which acted as resources for the construction of knowledge to teach with SSI. Among these, knowledge related to the nature of SSI, its approach to teaching and to the difficulties of students stands out. This learning was related to the uses that those teachers made of their experiences in discourse, which expanded or restricted their opportunities to learn in that context. Furthermore, our study of that group of Science teachers allowed us to understand that the incorporation (or not) of pedagogical practices aimed at teaching with SSI depends on their alignment with the demands faced in the profession. We hope that the understandings we reach with this investigation can inspire the promotion of continuing education courses that seek to develop fruitful scenarios for the creation and maintenance of discursive communities of teachers in which the sharing of their professional experiences enhances their learning. Furthermore, considering the social, contextual and situated nature of teaching knowledge, we suggest that more research be carried out in an attempt to give visibility to these aspects by adopting research logics that assume teachers interacting with each other as the unit of analysis
Efeito da temperatura nas propriedades físicas densidade, viscosidade e índice de refração do óleo de babaçu (Orbignya sp.) na faixa entre 293 e 333 K.
No full textThe investigation of vegetable oils' physical properties is indispensable to promote further applicability. In this sense, the density (ρ), absolute viscosity (μ), and refractive index (IR) of two brands of refined babassu oil (A and B) were obtained as a function of temperature (293.15 to 333.15 K). Mathematical models were adjusted to the experimental data. Babassu oil had an average percentage of saturated fatty acids of 85.60%. The ρ, μ and IR were inversely proportional to temperature and were influenced by the fatty acid composition and the degree of unsaturation of the oil. Arrhenius Model was the most accurate in explaining the variation of μ as a function of temperature. Time-dependent properties differed between samples, which highlights the importance of investigating different sources. The models obtained are useful for the disclosure of the physical properties of babassu oil, enabling its application in engineering processes and product development.A investigação das propriedades físicas dos óleos vegetais é indispensável para promover maior aplicabilidade. Nesse sentido, foram obtidas a densidade (ρ), a viscosidade absoluta (μ) e o índice de refração (IR) de duas marcas de óleo de babaçu refinado (A e B) em função da temperatura (293,15 a 333,15 K). Modelos matemáticos foram ajustados aos dados experimentais. O óleo de babaçu apresentou percentual médio de ácidos graxos saturados de 85,60%. Os ρ, μ e IR foram inversamente proporcionais à temperatura e foram influenciados pela composição de ácidos graxos e pelo grau de insaturação do óleo. O modelo de Arrhenius foi o mais preciso para explicar a variação de μ em função da temperatura. As propriedades dependentes do tempo diferiram entre as amostras, o que destaca a importância de investigar diferentes fontes. Os modelos obtidos são úteis para a divulgação das propriedades físicas do óleo de babaçu, possibilitando sua aplicação em processos de engenharia e desenvolvimento de produtos
Potential of piperine for neuroprotection in sepsis-associated encephalopathy.
No full textAims: Sepsis-associated encephalopathy (SAE) is a common complication that increases mortality and leads to long-term cognitive impairment in sepsis survivors. However, no specific or effective therapy has been identified for this complication. Piperine is an alkaloid known for its anti-inflammatory, antioxidant, and neuroprotective properties, which are important characteristics for treatment of SAE. The objective of this study was to evaluate the neuroprotective effect of piperine on SAE in C57BL/6 mice that underwent cecum ligation and perforation surgery (CLP).
Main methods: C57BL/6 male mice were randomly assigned to groups that underwent SHAM surgery or CLP. Mice in the CLP group were treated with piperine at doses of 20 or 40 mg/kg for short- (5 days) or long-term (10 days) periods after CLP.
Key findings: Our results revealed that untreated septic animals exhibited increased concentrations of IL-6, TNF, VEGF, MMP-9, TBARS, and NLRP3, and decreased levels of BDNF, sulfhydryl groups, and catalase in the short term. Additionally, the levels of carbonylated proteins and degenerated neuronal cells were increased at both time points. Furthermore, short-term and visuospatial memories were impaired. Piperine treatment reduced MMP-9 activity in the short term and decreased the levels of carbonylated proteins and degenerated neuronal cells in the long term. It also lowered IL-6 and TBARS levels at both time points evaluated. Moreover, piperine increased short-term catalase and long-term BDNF factor levels and improved memory at both time points.
Significance: In conclusion, our data demonstrate that piperine exerts a neuroprotective effect on SAE in animals that have undergone CLP
Intervenção nutricional dietética versus motivacional : modulação dos biomarcadores inflamatórios na hipertensão arterial.
No full textPrograma de Pós-Graduação em Saúde e Nutrição. Escola de Nutrição, Universidade Federal de Ouro Preto.A Hipertensão Arterial Sistêmica (HAS) é uma condição clínica multifatorial caracterizada por elevação sustentada dos níveis pressóricos. O processo inflamatório existente na hipertensão é uma resposta complexa que consiste em interações entre células inflamatórias, como macrófagos e linfócitos T, levando ao aumento da expressão de moléculas de adesão, citocinas, metaloproteinases de matriz e fatores de crescimento. Nesse sentido, alguns marcadores bioquímicos têm sido sugeridos como auxiliares do diagnóstico e do acompanhamento de pacientes com hipertensão, com destaque para TNF- e IL-6. Uma das principais recomendações não medicamentosas no tratamento da hipertensão é a alimentação adequada e saudável. Objetivo: Avaliar se existe diferença entre a intervenção dietética nutricional tradicional e a intervenção dietética por entrevista motivacional na modulação dos parâmetros inflamatórios e sua correlação com a HAS em usuários da Atenção Primária à Saúde (APS). Métodos: O projeto foi realizado com pacientes hipertensos, moradores de Ouro Preto com idade a partir de 20 anos. A primeira etapa foi a linha de base com caracterização da amostra, análise dos fatores associados aos níveis pressóricos e coleta de sangue para análise bioquímica e dos biomarcadores PCR e IL-6. A segunda foi a intervenção nutricional composta de dois grupos: Intervenção convencional – atendimento convencional pautado na dietoterapia vigente para a hipertensão e; Intervenção motivacional – atendimento pautado na teoria da entrevista motivacional e nas orientações da segunda edição do Guia Alimentar para a População Brasileira. A terceira etapa consistiu na avaliação da efetividade da Intervenção Nutricional com a coleta de sangue para a análise bioquímica após 6 meses de intervenção nutricional. Resultados: Na análise entre grupos houve diferença significativa após a intervenção para colesterol (p=0,004) e LDL (p=0,002).Systemic Arterial Hypertension (SAH) is a multifactorial clinical condition characterized by a sustained increase in blood pressure levels. The inflammatory process in hypertension is a complex response that consists of interactions between inflammatory cells, such as macrophages and T lymphocytes, leading to increased expression of adhesion molecules, cytokines, matrix metalloproteinases and growth factors. In this sense, some biochemical markers have been suggested as aids in the diagnosis and monitoring of patients with hypertension, with emphasis on TNF- and IL-6. One of the main non-drug recommendations in the treatment of hypertension is adequate and healthy eating. Objective: To evaluate whether there is a difference between traditional nutritional dietary intervention and dietary intervention using motivational interviewing in the modulation of inflammatory parameters and their correlation with hypertension in users of Primary Health Care (PHC). Methods: The project was carried out with hypertensive patients, residents of Ouro Preto aged 20 and over. The first stage was the baseline with sample characterization, analysis of factors associated with blood pressure levels and blood collection for biochemical analysis and PCR and IL-6 biomarkers. The second was the nutritional intervention composed of two groups: Conventional intervention – conventional care based on current diet therapy for hypertension and; Motivational intervention – service based on the theory of motivational interviewing and the guidelines of the second edition of the Food Guide for the Brazilian Population. The third stage consisted of evaluating the effectiveness of the Nutritional Intervention by collecting blood for biochemical analysis after 6 months of nutritional intervention. Results: In the analysis between groups, there was a significant difference after the intervention for cholesterol (p=0.004) and LDL (p=0.002)
Hydrothermal co-liquefaction of microalgae, sugarcane bagasse, brewer's spent grain, and sludge from a paper recycling mill : modeling and evaluation of biocrude and biochar yield.
No full textBiomass can be used as an energy source to thermochemical conversion processes to biocrude production.
However, the supply and dependence on only one biomass for biocrude production can be an obstacle due to its
seasonality, availability, and logistics costs. In this way, biomass waste and agroindustrial residues can be
mixture and used as feedstock to the hydrothermal co-liquefaction (co-HTL) process as an alternative to
obtaining biocrude. In this sense, the present paper analyzed the biocrude yield influence of the co-HTL from a
quaternary unprecedented blend of different biomasses, such as sugarcane bagasse, brewer’s spent grain (BSG),
sludge from a paper recycling mill (PRM), and microalgae (Chlorella vulgaris). In this way, a simplex lattice design
was employed and co-HTL experiments were carried out in a 2000 mL high-pressure stirred autoclave reactor
under 275 ◦C for 60 min, considering 15% of feedstock/water ratio. Significant effects in each feedstock and their
blends were analyzed aiming to increase biocrude and biochar yield. It was found that the addition of microalgae
is only significant when considered more than 50% into the blend with BSG and PRM sludge to increase biocrude
yield
In situ Pb–Pb garnet geochronology as a tool for investigating polymetamorphism : a case for Paleoarchean lateral tectonic thickening.
No full textThe Barberton Granite–Greenstone Belt remains a key location in the debate concerning the nature of Archean tectonic processes. Much work has focused on deciphering the tectonic significance of the c. 3.23 Ga metamorphism, as this has been correlated with lower geothermal gradient conditions potentially indicating Archean subduction. However, several studies also found evidence of an earlier, 3.45 Ga metamorphic episode, overprinted by the 3.23 Ga event. Here we apply in situ Pb–Pb dating and P–T modelling to a large (3 cm diameter) garnet crystal, allowing for the direct dating of the metamorphic conditions obtained from the garnet. The garnet core produced an isochron age of 3435 + 45 Ma, corresponding to an increase in P and T evolution reaching peak conditions of at least 7 kbar and 700°C. Analyses obtained from the garnet rim give an isochron age of 3245 + 41 Ma, corresponding to P–T conditions reaching 8–9 kbar and 700°C. The preservation of two moderate- to high-pressure events occurring 200 million years apart is consistent with lateral tectonic processes producing crustal thickening at 3.2 Ga and may also be a viable process for the earlier event
Quem está falando? : o uso de fontes em podcasts jornalísticos diários.
No full textPrograma de Pós-Graduação em Comunicação. Instituto de Ciências Sociais Aplicadas, Universidade Federal de Ouro Preto.A presente pesquisa aborda a ascensão dos podcasts no Brasil e sua relação com o
jornalismo, destacando os desafios enfrentados na produção desses programas, a
convergência nas práticas jornalísticas e a seleção de fontes nos podcasts diários.
Apresenta-se como problema central o seguinte questionamento: quais fontes são usadas
nos podcasts jornalísticos diários? Buscando responder a essa pergunta, recorremos a
autores das Teorias do Jornalismo (Lage, 2002; Traquina, 2012; e Wolf, 2012), àqueles
que categorizam as fontes na impresa tradicional (Chaparro, 2009; Schimitz, 2011), e
aos que pensam especificamente no cenário do rádio (Ortriwano, 1985; Ferraretto,
2012; Zuculoto, 2012; Kischinhevsky; 2009 e Lopez; 2010). O caminho metodológico é
divido em a) levantamento de dados, por meio da etnografia de podcasts (Lündstrom e
Lündstrom, 2021), do Estudo de Caso (Yin, 2010; Martino, 2018) e e da Semana
Construída (Bauer, 2002); e b) análise desses dados, recorrendo à ferramenta de Análise
de Conteúdo de Laurence Bardin (1977). Discute-se, ainda, as possibilidades e desafios
de aplicação da AC em objetos sonoros, levando em conta as contribuições de
Quadros et al (2014), Kischinhevsky et al (2016) e Sampaio et al (2022). O corpus de
análise é composto por dez edições de 123 Segundos, podcast da Rádio BandNews FM;
cinco edições de Café da Manhã, podcast do jornal Folha de São Paulo; e cinco edições
de Durma com Essa, podcast do jornal digital Nexo. A ficha para Análise de Conteúdo
é composta por cinco unidades de registro e dezenove unidades de análise. Como
conclusão e contribuição de pesquisa, parte-se da categorização de fontes de Chagas
(2020), para a proposição de uma nova macro categoria, a fonte documental.This research looks at the rise of podcasts in Brazil and their relationship with
journalism, highlighting the challenges faced in producing these programs, convergence
in journalistic practices and the selection of sources in daily podcasts. The central
problem is the following question: which sources are used in daily journalistic podcasts?
In an attempt to answer this question, we turned to authors from journalism theory
(Lage, 2002; Traquina, 2012; and Wolf, 2012), those who categorize sources in the
traditional press (Chaparro, 2009; Schimitz, 2011), and those who think specifically
about the radio scenario (Ortriwano, 1985; Ferraretto, 2012; Zuculoto, 2012;
Kischinhevsky; 2009 and Lopez; 2010). The methodological path is divided into a) data
collection, through podcast ethnography (Lündstrom and Lündstrom, 2021), the Case
Study (Yin, 2010; Martino, 2018) and the constructed week (Bauer, 2002); and b)
analysis of this data, using Laurence Bardin's Content Analysis tool (1977). The
possibilities and challenges of applying CA to sound objects are also discussed, taking
into account the contributions of Quadros et al (2014), Kischinhevsky et al (2016) and
Sampaio et al (2022). The corpus of analysis consists of ten editions of 123 Segundos, a
podcast from Rádio BandNews FM; five editions of Café da Manhã, a podcast from the
newspaper Folha de São Paulo; and five editions of Durma com Essa, a podcast from
the digital newspaper Nexo. The Content Analysis form consists of five recording units
and nineteen analysis units. As a conclusion and research contribution, the
categorization of sources by Chagas (2020) is used to propose a new macro category,
the documentary source
