Position affects performance in multiple-object tracking in rugby union players

We report an experiment that examines the performance of rugby union players and a control group composed of graduate student with no sport experience, in a multiple-object tracking task. It compares the ability of 86 high level rugby union players grouped as Backs and Forwards and the control group, to track a subset of randomly moving targets amongst the same number of distractors. Several difficulties were included in the experimental design in order to evaluate possible interactions between the relevant variables. Results show that the performance of the Backs is better than that of the other groups, but the occurrence of interactions precludes an isolated groups analysis. We interpret the results within the framework of visual attention and discuss both, the implications of our results and the practical consequences.Fil: Martín, Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; ArgentinaFil: Sfer, Ana María. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología; ArgentinaFil: D'urso Villar, Marcela Adriana. Universidad Nacional de Tucumán; ArgentinaFil: Barraza, Jose Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; Argentin

Pupil dynamics with periodic flashes: Effect of age on mesopic adaptation

The purpose of this study is to determine the pupillary dynamics with periodical flashes from a peripheral glare source, in similar conditions to night driving, while focusing on dependence with age. We measured two groups of people: youth and adults. Maximum pupil size decreases due to periodic flashes. Latency does not present significant differences. The reduction of pupil size is greater for older adults. The presence of a peripheral and periodic glare source modifies the pupil size. This leads to a reduction of retinal illuminance, which is greater for older adults.Fil: Silva, Bárbara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; ArgentinaFil: Sfer, Ana María. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Matemática. Cátedra de Probabilidades y Estadísticas; ArgentinaFil: D'urso Villar, Marcela Adriana. Universidad Nacional de Tucumán. Facultad de Medicina. Departamento de Investigación. Área de Bioestadística; ArgentinaFil: Issolio, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; ArgentinaFil: Colombo, Elisa Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; Argentin

Effect of probiotic lactobacilli supplementation on growth parameters, blood profile, productive performance, and fecal microbiology in feedlot cattle

Lactic acid bacteria (LAB) selected on the basis of probiotic characteristics were administered to beef feedlot catlle and the effect on body condition/growth and nutritional-metabolic status as well as on E. coli O157:H7 fecal shedding, were investigated. A feeding trials involving 126 steers were used to evaluate the effects of Lactobacillus acidophilus CRL2074, Limosilactobacillus fermentum CRL2085 and Limosilactobacillus mucosae CRL2069 and their combinations (5 different probiotic groups and control) when 107-108 CFU/animal of each probiotic group were in-feed supplemented. Cattle were fed a high energy corn-based diet (16 to 88%) and samples from each animal were taken at 0, 40, 104 and 163 days. In general, animals body condition and sensorium state showed optimal muscle-skeletal development and behavioral adaption to confinement; no nasal/eye discharges and diarrheic feces were observed. The nutritional performance of the steers revealed a steady increase of biometric parameters and weight. Animals supplied with L. mucosae CRL2069 for 104 days reached the maximum mean live weight (343.2 kg), whereas the greatest weight daily gain (1.27 ± 0.16 Kg/day) was obtained when CRL2069 and its combination with L. fermentum CRL2085 (1.26 ± 0.11 kg/day) were administered during the complete fattening cycle. With several exceptions, bovine cattle blood and serum parameters showed values within referential ranges. As a preharvest strategy to reduce Escherichia coli O157:H7 in cattle feces, CRL2085 administered during 40 days decreased pathogen shedding with a reduction of 43% during the feeding period. L. fermentum CRL2085 and L. mucosae CRL2069 show promise for feedlot cattle feeding supplementation to improve metabolic-nutritional status, overall productive performance and to reduce E. coli O157:H7 shedding, thus decreasing contamination chances of meat food products.Fil: Mansilla, Flavia Ivana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Miranda, Maria Hortencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Uezen, Jose David. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Maldonado, Natalia Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: D'urso Villar, Marcela Adriana. Universidad Nacional de Tucumán; ArgentinaFil: Merino, Luis Antonio. Universidad Nacional del Nordeste; ArgentinaFil: Vignolo, Graciela Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Nader Macias, Maria Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin