54 research outputs found

    O ENREDO DAS AULAS EXPERIMENTAIS NO ENSINO FUNDAMENTAL: CONCEPÇÕES DE PROFESSORES SOBRE ATIVIDADES PRÁTICAS NO ENSINO DE CIÊNCIAS

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    Resumo: A literatura especializada vem apontando mudanças no ensino de ciências e exprime a experimentação como uma alternativa para o processo de construção de saberes científicos por meio da reflexão e investigação. No contexto nacional, o cenário escolar mantém práticas pedagógicas ainda resistentes às mudanças relacionadas a alfabetização científica mediadas por práticas experimentais. Assim, a presente pesquisa objetivou investigar a concepção de professores de ciências sobre de implementação de práticas experimentais em escolas da rede pública de Ensino Fundamental. Com base nos aspectos metodológicos de uma abordagem qualitativa, os dados foram tratados por análise de conteúdo e organizados na perspectiva de uma rede sistêmica. Os resultados obtidos revelaram que os professores de ciências compreendem a importância da utilização da experimentação para construção de saberes científicos, porém, os planejamentos escolares não contemplam a inserção efetiva dessas atividades, tendo como principais fatores a falta de recursos e espaço próprio destinado à prática experimental.Palavras-chave: Ensino de Ciências; Práticas Experimentais; Professores de Ciências. Abstract: The specialized literature has pointed out changes in science education and expresses experimentation as an alternative to the process of building scientific knowledge through reflection and investigation. In the national context, the school scenario maintains pedagogical practices that are still resistant to changes related to scientific literacy mediated by experimental practices. Thus, the present research aimed to investigate the conception of science teachers about the implementation of experimental practices in public elementary schools. Based on the methodological aspects of a qualitative approach, the data were treated by content analysis and organized from the perspective of a systemic network. The results obtained revealed that science teachers understand the importance of using experimentation to build scientific knowledge, however, school planning does not include the effective insertion of these activities, having as main factors the lack of resources and proper space for experimental practice.Keywords: Science Teaching; Experimental Practices; Science Teachers

    Mammals in Portugal: a data set of terrestrial, volant, and marine mammal occurrences in Portugal

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    Mammals are threatened worldwide, with ~26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mammals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems functionality and resilience, and therefore information on their distribution is crucial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mammals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occurring in 2000 and 2021). The methods used to collect the data were: live observations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows | soil mounds | tunnel, (2) capture, (3) colony, (4) dead animal | hair | skulls | jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping | video, (10) predators diet | pellets | pine cones/nuts, (11) scat | track | ditch, (12) telemetry and (13) vocalization | echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n =31,573) has the highest number of records followed by Chiroptera (n = 18,857), Carnivora (n = 18,594), Lagomorpha (n = 17,496), Cetartiodactyla (n = 11,568) and Eulipotyphla (n = 7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n = 12,159], Monachus monachus [n = 1,512], and Lynx pardinus [n = 197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contribute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications

    COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

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    Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

    Evaluation of Antibacterial, Antineoplastic, and Immunomodulatory Activity of Paullinia cupana Seeds Crude Extract and Ethyl-Acetate Fraction

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    Paullinia cupana (Guarana) is a native plant of Amazon region that has very traditional importance. Its seeds are rich in bioactive compounds, including tannins, which exhibit relevant properties. Objective. This study aimed to evaluate antibacterial, antineoplastic, and immunomodulatory activity of P. cupana seeds crude extract (CE) and ethyl-acetate fraction (EAF). Methods. Antibacterial activity was evaluated by determination of minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). Antineoplastic activity was evaluated by MTT assays in hepatocellular carcinoma (HepG2), breast adenocarcinoma (MCF-7), ductal carcinoma (T47-D), non-Hodgkin’s B cell lymphoma (Toledo), T cell leukemia (Jukart), and Acute Leukemia (HL-60) cell lines. BALB/c mice splenocytes were treated to assess IFN-γ, IL-6, IL-17, and IL-10 levels by sandwich ELISA. Results. CE and EAF were not toxic to peripheral blood cells and splenocytes. CE and EAF fractions showed a bacteriostatic activity (MIC = 250 μg/mL) and presented IC50 values of 70.25 μg/mL and 61.18 μg/mL in HL-60 leukemia cell line. All cytokines evaluated had their levels reduced after treatment, following dose-response model. Discussion and Conclusion. Different biological activities were observed for both CE and EAF, suggesting P. cupana as a source of bioactive substances, especially tannins that may be used for several diseases treatments
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