ABSTRACT The burnout variable has been studied in different professions; however, it presents challenges in its measurement. The present study provides evidence of validity based on the internal structure of the Burnout Syndrome Assessment Scale in Public Security Workers (EASB-SP) and presents the estimation of item parameters through the Item Response Theory (IRT). A total of 10,885 public security agents from all states of Brazil participated in the study. The analyses indicated a three-factor structure, with adequate reliability indices and discrimination of the items. The Professional Fulfillment factor presented a lower theta value to be endorsed. The instrument was shown to be an adequate measure, with evidence of validity for the context of Brazilian public security.

RESUMO O Burnout tem sido uma variável estudada em diferentes profissões, embora com desafios em sua medida. O presente estudo apresenta evidências de validade baseada na estrutura interna da Escala de Avaliação da Síndrome de Burnout (EASB-SP) para a segurança pública, além de apresentar a estimativa dos parâmetros dos itens por meio da Teoria de Resposta ao Item (TRI). Participaram do estudo 10.885 agentes da segurança pública de todas as unidades federativas do Brasil. As análises indicaram uma estrutura tri-fatorial, com índices de fidedignidade e discriminação dos itens adequados. O fator de realização profissional indicou menor theta para ser endossado. O instrumento em questão apresenta-se como uma medida adequada e com evidências de validade para o contexto de segurança pública brasileira.

ABSTRACT A fractional order mathematical model that already exists in the literature, was considered. This model was established to study the effects of medicinal treatment in people infected with the human immunodeficiency virus (HIV). The importance of this study is that the model evaluates, among other parameters, the density of healthy and HIV-infected CD4+ T cells. These data are very necessary for the subject infected by the virus given the effects that an antiretroviral treatment causes in it. The objective of this work is to consider several numerical schemes that involve fractional derivatives in order to compare their behaviors and to obtain a good approximation of the mentioned model solution. Convergence of these schemes will be studied as well as sensitivity with respect to the variation of the parameters η (drug efficacy) and α (fractional derivative order). Furthermore, through the collection of medical records of people living with HIV, it is intended to determine the optimal fractional derivative order for the model and to compare it with the classical model.

Brachiaria brizantha é a espécie forrageira mais utilizada atualmente no Brasil e exportada para diversos países. Para uma boa formação, é fundamental que apresentem alta germinação e vigor. É comum, que algumas cultivares dessa espécie, apresentem dormência natural, interferindo negativamente naquele processo. No presente trabalho avaliou-se o efeito de diferentes tipos de tratamentos na quebra de dormência de B. brizantha. O trabalho foi realizado na Universidade Estadual de Mato Grosso do Sul, na Unidade Universitária de Aquidauana. Os ensaios foram conduzidos em delineamento casualizado, em esquema fatorial com quatro tratamentos para a quebra de dormência - H2SO4, KNO3, tratamento térmico e testemunha - x três cultivares de B. brizantha (‘‘Marandu’’, ‘MG5’ e ‘Piatã’), com cinco repetições. As contagens de germinação foram realizadas aos 7, 14 e 21 dias após o inicio do ensaio e os dados expressos em percentagem final de germinação. Observaram-se diferenças significativas (p<0,05) entre os tratamentos. A escarificação com H2SO4 induziu quebras de dormência das sementes significativamente superiores às dos outros tratamentos, em particular na cv. ‘Piatã’.

Brachiaria brizantha is the forage species most currently used in Brazil and exported to several countries. For a good training, it is essential high germination and vigor. It is common that some cultivars of this species present natural dormancy that negatively affects the germination process. In this work we evaluated different types of seed treatment for breaking dormancy in B. brizantha cultivars. The work was realized at the State University of Mato Grosso do Sul in the Unit University Aquidauana. The experiment was conducted in a completely randomized design, in a factorial design with four treatments for breaking dormancy - H2SO4, KNO3, heat treatment and control - x three cultivars of B. brizantha (‘‘Marandu’’, ‘MG5’ and ‘Piatã’) with five replications. Germination counts were performed at 7, 14 and 21 days after the start of the assays and the data expressed in final germination percentage. Significant differences (p <0.05) between treatments were registered, being scarification with H2SO4 the best treatment for the breaking of dormancy. The cv. ‘Piatã’ showed significant higher germination percentage than the two other cultivars.