Resumo: Este trabalho teve como objetivo principal investigar como a abundância e a riqueza de mariposas Arctiinae variam temporalmente, ao longo do período noturno. Especificamente, analisamos as seguintes questões: (1) existe relação entre a abundância e a riqueza de Arctiinae e a umidade relativa do ar e a temperatura? (2) qual é o horário de atividade de cada espécie de mariposa? (3) a composição de espécies difere ao longo da noite? (4) é necessário amostrar esse grupo de mariposas ao longo de toda a noite para ter uma amostra representativa das espécies? Realizamos as amostragens no Parque Nacional das Emas (17°49’-18°28’S e 52°39’-53°10’W), Brasil. Selecionamos sete pontos amostrais em uma área de campo cerrado. Em cada ponto, coletamos as mariposas Arctiinae utilizando uma fonte luminosa (lâmpada UV de 15 W) refletida em um pano branco (2 x 3 m) estendido na vertical. Coletamos as mariposas durante sete noites consecutivas (uma noite por ponto, entre os dias 13 e 19 de dezembro de 2012, das 19:00 até as 07:00). Dividimos o período noturno em doze faixas de uma hora. Medimos a temperatura e a umidade relativa do ar com auxílio de um termohigrômetro digital. Amostramos 149 indivíduos pertencentes a 17 espécies de mariposas Arctiinae. A maioria das espécies (70,5%) esteve ativa apenas por uma ou duas horas durante a noite. As espécies diferiram em termos de horário de atividade. O horário das 20 h apresentou uma maior abundância (44 indivíduos), seguido do horário das 21 (38) e das 22 h (23). A riqueza também foi maior nas primeiras horas da noite. Somente a temperatura foi positivamente correlacionada com a abundância de mariposas. A riqueza de mariposas não foi influenciada nem pela temperatura nem pela umidade relativa do ar. As possíveis causas das diferenças em termos de horários de atividade são discutidas..

Abstract: The main goal of this work was to investigate how the abundance and richness of Arctiinae moths varies over time, during the night. Specifically, we analyzed the following questions: (1) Is there a relationship between Arctiinae abundance and richness with the temperature and relative humidity? (2) What are the hours of activity of each species of moth? (3) Does the species composition differ over night? (4) Is it necessary to sample this group of moths throughout the night to have a representative sample of the species? We sampled the moths in Emas National Park (17°49’-18°28’S and 52°39’-53°10’W), Brazil. We selected seven sampling points in an area of savanna. At each sampling point, we collected the Arctiinae moths with a light trap (with a 15-W black light fluorescent light bulb), reflected in a white cloth (2 x 3 m) extended vertically. We sampled the moths in seven consecutive nights (one night in each sampling point, from December 13 to December 19, 2012, from 7 p.m. until 7 a.m.). We divided the samplings in twelve periods over the night, with an hour each. At each period of time, we measured the temperature and the relative humidity with a digital termohygrometer. We sampled 149 individuals belonging to 17 species of Arctiinae moths. Most species (70.5%) were active only for one or two hours at night. The species differed in terms of time activity. The higher abundance occurred at 8 p. m. (44 individuals), followed by 38 individuals at 9 p. m. and 23 at 10 p. m. The species richness was also higher in the early hours of the night. The temperature was the only variable that showed a positive and significative relationship with the Arctiinae moth abundance. The species richness was not influenced neither by the temperature nor by the relative air humidity. The possible causes of the peak of abundance and species richness in specific hours of the night are discussed.

Typical and atypical enteropathogenic Escherichia coli (EPEC) are considered important bacterial causes of diarrhoea. Considering the repertoire of virulence genes, atypical EPEC (aEPEC) is a heterogeneous group, harbouring genes that are found in other diarrheagenic E. coli pathotypes, such as those encoding haemolysins. Haemolysins are cytolytic toxins that lyse host cells disrupting the function of the plasma membrane. In addition, these cytolysins mediate a connection to vascular tissue and/or blood components, such as plasma and cellular fibronectin. Therefore, we investigated the haemolytic activity of 72 aEPEC isolates and determined the correlation of this phenotype with the presence of genes encoding enterohaemolysins (Ehly) and cytolysin A (ClyA). In addition, the correlation between the expression of haemolysins and the ability of these secreted proteins to adhere to extracellular matrix (ECM) components was also assessed in this study. Our findings demonstrate that a subset of aEPEC presents haemolytic activity due to the expression of Ehlys and/or ClyA and that this activity is closely related to the ability of these isolates to bind to ECM components.