1,942 research outputs found

    Colony size predicts division of labour in Attine ants

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    Division of labour is central to the ecological success of eusocial insects, yet the evolutionary factors driving increases in complexity in division of labour are little known. The size–complexity hypothesis proposes that, as larger colonies evolve, both non-reproductive and reproductive division of labour become more complex as workers and queens act to maximize inclusive fitness. Using a statistically robust phylogenetic comparative analysis of social and environmental traits of species within the ant tribe Attini, we show that colony size is positively related to both non-reproductive (worker size variation) and reproductive (queen–worker dimorphism) division of labour. The results also suggested that colony size acts on non-reproductive and reproductive division of labour in different ways. Environmental factors, including measures of variation in temperature and precipitation, had no significant effects on any division of labour measure or colony size. Overall, these results support the size–complexity hypothesis for the evolution of social complexity and division of labour in eusocial insects. Determining the evolutionary drivers of colony size may help contribute to our understanding of the evolution of social complexity

    Colony size predicts division of labour in Attine ants

    Get PDF
    Division of labour is central to the ecological success of eusocial insects, yet the evolutionary factors driving increases in complexity in division of labour are little known. The size–complexity hypothesis proposes that, as larger colonies evolve, both non-reproductive and reproductive division of labour become more complex as workers and queens act to maximize inclusive fitness. Using a statistically robust phylogenetic comparative analysis of social and environmental traits of species within the ant tribe Attini, we show that colony size is positively related to both non-reproductive (worker size variation) and reproductive (queen–worker dimorphism) division of labour. The results also suggested that colony size acts on non-reproductive and reproductive division of labour in different ways. Environmental factors, including measures of variation in temperature and precipitation, had no significant effects on any division of labour measure or colony size. Overall, these results support the size–complexity hypothesis for the evolution of social complexity and division of labour in eusocial insects. Determining the evolutionary drivers of colony size may help contribute to our understanding of the evolution of social complexity

    Religion as a protective factor against drug use among brazilian university students: a national survey

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    OBJECTIVE: To investigate the relationship between religiosity and drug use among Brazilian university students. METHODS: This manuscript is part of the "First Nationwide Survey on the Use of Alcohol, Tobacco and Other Drugs among College Students in the 27 Brazilian State Capitals". In this study, 12,595 university students were divided into two groups according to their attendance at religious services: frequent attenders (FR; 39.1%) and non-frequent attenders (NFR; 60.8%). Subsequently, we analyzed their responses to a structured, anonymous questionnaire on drug use and other behaviors. Individual multivariate logistic regression models tested the association between religiosity and drug use (alcohol, tobacco, marijuana and at least one illicit drug). RESULTS: Drug use over the last 30 days was higher among NFR students even after controlling for demographic variables. NFR students were more likely to use alcohol OR = 2.52; 95% CI: 2.08-3.06, tobacco (2.83; 2.09-3.83), marijuana (2.09; 1.39-3.11) and at least one illicit drug (1.42; 1.12-1.79) compared to FR students. CONCLUSION: Religiosity was found to be a strongly protective factor against drug use among Brazilian university students. However, more studies are needed to identify the mechanisms by which religiosity exerts this protective influence.

    Breve retrospectiva da orizicultura catarinense

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    A cultura do arroz irrigado no Estado de Santa Catarina destaca-se pela sua importância social e econômica, com cerca de 5.900 estabelecimentos agropecuários produtores localizados em 93 municípios, que tem na atividade sua principal fonte de renda. A grande maioria desses estabelecimentos possuem, em média, 25 hectares e são de propriedade de pequenos e médios agricultores que utilizam predominantemente mão-de-obra familiar. O estado de Santa Catarina possui o segundo maior volume de produção de arroz do país com 1.254,1 mil toneladas na safra 2019/20. &nbsp

    Chemical empty body composition estimation of Nellore and Caracu bulls using the chemical and physical compositions of the 9th-10th-11th rib cut

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    Foram desenvolvidas equações para estimar a composição química corporal de bovinos de três grupos genéticos (Caracu, CaS; Nelore seleção, NeS; e Nelore controle, NeC) a partir das composições química e física do corte da 9ª-10ª-11ª costelas. Utilizaram-se 56 machos não-castrados (20 CaS, 20 NeS e 16 NeC) abatidos aos 20-24 meses de idade. A composição química em água, proteína, extrato etéreo e minerais foi determinada no corte das costelas e em amostras obtidas após moagem completa e homogeneização de todos os tecidos corporais, separados em sangue, couro, cabeça + patas, vísceras e carcaça. Os componentes físicos músculo, gordura e ossos foram também separados no corte das costelas. As melhores estimativas dos componentes do corpo vazio foram obtidas utilizando-se como estimadores os mesmos componentes no corte das costelas. A utilização dos totais de água e extrato etéreo do corte das costelas permitiu estimar com precisão os totais de água, extrato etéreo e proteína no corpo vazio dos animais. O uso das quantidades de músculo e gordura no corte das costelas possibilitou estimar com eficiência os totais de água, extrato etéreo e proteína no corpo vazio. Para estimação do total de cinzas do corpo vazio, foram encontradas três equações múltiplas (uma para cada grupo genético) com coeficientes de determinação satisfatórios. Essas equações incluíram como estimadores as quantidades de músculo e gordura nas costelas. As composições química e física do corte das costelas possibilitam estimar satisfatoriamente os componentes químicos do corpo vazio dos animais. Equações descritas na literatura permitem estimar com precisão os teores de extrato etéreo e água no corpo vazio dos animais deste estudo.Linear regressions were developed to estimate the chemical empty body composition of cattle from three genetic groups (Caracu, CaS; Selected Nellore, NeS; and Control Nellore, NeC) using the physical and chemical compositions of the 9th-10th-11th rib section. Fifty six intact males (20 CaS, 20 NeS and 16 NeC) were slaughtered at 20-24 months of age. The content of water, protein, ether extract and ashes were determined in rib section and on samples obtained after grinding and homogenization of all body tissues (blood, hide, head + feet, viscera and carcass). The physical components muscle, fat and bones were also determined in the rib section. The best estimates of empty body components were obtained using the same estimator components as in rib section. The amounts of water and ether extract of the rib section accurately allowed to estimate the total water, ether extract and protein in the empty body of animals. The amounts of muscle and fat in the rib section allowed estimating with efficiency the total of water, ether extract and protein in the empty body of animals. To estimate the empty body total ashes three multiple equations were developed (one for each genetic group) with satisfactory coefficients of determination. These equations included as estimators the amounts of muscle and fat in the rib section. The physical and chemical compositions of the rib section can satisfactorily estimate the chemical components of the empty body of animals. Equations described in the literature can estimate with precision the amounts of ether extract and water in the body empty of animals of this study

    EXOGENOUS APPLICATION OF VITAMINS IN UPLAND RICE

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    Vitamin application can optimize plant growth and grain yield of rice crop due to its beneficial effect on many plant physiological characteristics. The present study was conducted to evaluate the effects of niacin and thiamin applied as seed soaking or foliar spray on the morphological and productive characteristics of upland rice crop (Oryza sativa L., cv. Primavera), grown under greenhouse conditions. The experiment was arranged in a randomized block design in a 4 x 2 factorial scheme, with four replicates. The treatments consisted of the application of vitamins (control; 200 mg L-1 thiamin; 200 mg L-1 niacin; and 100 mg L-1 thiamin + 100 mg L-1 niacin) and two application methods (seed soaking and foliar spraying). Morphological and productive characteristics of the rice plants were evaluated. The exogenous application of thiamin and niacin, regardless of the application method, has a beneficial effect on the growth of upland rice plants, but does not increase the grain yield of the crop

    Cervical cancer screening coverage in a high-incidence region

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    OBJECTIVE To analyze the coverage of a cervical cancer screening program in a city with a high incidence of the disease in addition to the factors associated with non-adherence to the current preventive program.METHODS A cross-sectional study based on household surveys was conducted. The sample was composed of women between 25 and 59 years of age of the city of Boa Vista, RR, Northern Brazil who were covered by the cervical cancer screening program. The cluster sampling method was used. The dependent variable was participation in a women’s health program, defined as undergoing at least one Pap smear in the 36 months prior to the interview; the explanatory variables were extracted from individual data. A generalized linear model was used.RESULTS 603 women were analyzed, with an mean age of 38.2 years (SD = 10.2). Five hundred and seventeen women underwent the screening test, and the prevalence of adherence in the last three years was up to 85.7% (95%CI 82.5;88.5). A high per capita household income and recent medical consultation were associated with the lower rate of not being tested in multivariate analysis. Disease ignorance, causes, and prevention methods were correlated with chances of non-adherence to the screening system; 20.0% of the women were reported to have undergone opportunistic and non-routine screening.CONCLUSIONS The informed level of coverage is high, exceeding the level recommended for the control of cervical cancer. The preventive program appears to be opportunistic in nature, particularly for the most vulnerable women (with low income and little information on the disease). Studies on the diagnostic quality of cervicovaginal cytology and therapeutic schedules for positive cases are necessary for understanding the barriers to the control of cervical cancer.OBJETIVO Analisar a cobertura do programa de rastreamento do câncer do colo uterino em município com alta incidência da doença e os fatores relacionados à não adesão ao programa preventivo vigente.MÉTODOS Foi realizado estudo transversal, com base em inquérito domiciliar. A amostra foi composta por mulheres entre 25 e 59 anos de idade do município de Boa vista, RR, Brasil, com cobertura pelo programa de rastreamento do câncer do colo uterino. Foi utilizado o método de amostragem por conglomerado. A variável dependente foi a adesão ao programa de saúde da mulher, definida como a realização de pelo menos um teste de Papanicolaou nos 36 meses anteriores à data da entrevista; as variáveis explicativas foram extraídas a partir de informações individuais. Foi utilizado modelo linear generalizado.RESULTADOS Foram analisadas 603 mulheres, com idade média de 38,2 anos (DP = 10,2). Quinhentas e dezessete mulheres realizaram o exame, sendo a prevalência de realização, nos últimos três anos, de 85,7% (IC95% 82,5;88,5). Renda familiar per capita elevada e consulta médica recente associaram-se à menor taxa de não realização do exame na análise multivariada. O desconhecimento da doença, das causas e dos meios de prevenção correlacionou-se com a chance de não adesão ao rastreamento. Vinte por cento das mulheres relataram realização do exame em caráter oportunístico, e não rotineiro.CONCLUSÕES A cobertura informada é elevada, acima do recomendado para controle do câncer do colo uterino. O programa preventivo apresenta caráter oportunístico, sobretudo para as mulheres mais vulneráveis (com baixa renda e pouca informação sobre a doença). Estudos sobre a qualidade diagnóstica da citologia cervicovaginal e dos itinerários terapêuticos dos casos positivos são necessários para compreensão das barreiras para o controle do câncer do colo uterino

    Educação remota: reflexões acerca do ensino a distância em tempos de pandemia

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    Em janeiro de 2020 houve o início de um surto de doença respiratória; em 11 de março, a pandemia COVID-19 atingia o mundo todo. Para contê-la, foi recomendado isolamento social. Desde então, escolas públicas no Brasil estão adotando o ensino remoto. O objetivo do trabalho é apresentar algumas reflexões acerca das possibilidades e dificuldades observadas no processo de ensino e aprendizagem do ensino remoto na pandemia do COVID-19. Para tanto, serão recrutadas referências bibliográficas da área da Educação para corroborar com as discussões aqui empreendidas. O Ensino a Distância já existia e diversas metodologias foram desenvolvidas, mas não voltadas especificamente para o Ensino Básico. Assim, observa-se que com a pandemia não houve aplicabilidade metodológica coletiva das boas práticas para o ensino remoto. Até o presente momento, maio de 2021, são três semestres letivos sem aulas presenciais regulares e ainda não há vacina para imunizar todos. No retorno presencial, espera-se dos docentes a retomada do conteúdo que deveria ter sido ensinado e aprendido pelos escolares em prazo recorde. Dessa forma, há que se debruçar acerca das práticas de ensino e aprendizagem no ensino remoto e das metodologias já discutidas e implementadas no EaD em outros níveis de ensino para que se (re)pense os acontecimentos educacionais no período de pandemia no Brasil
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