Distribution, forme et contenu des communications verbales dans deux groupes de formation

Thèse de doctorat -- Université catholique de Louvain, 197

Fusion (F) protein gene of newcastle disease virus: Sequence and hydrophobicity comparative analysis between virulent and avirulent strains

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Left inferior frontal cortex is involved in probabilistic serial reaction time learning

Cerebral blood flow was estimated using positron emission tomography and H2015 infusions in 12 volunteers while they were trained on the probabilistic serial reaction time task developed by Jimenez, Mendez, and Cleeremans (1996). Participants' reaction times to predictable and nonpredictable stimuli showed increasing sensitivity to the probabilistic constraints set by previous elements of the sequence. Analysis by statistical parametric mapping showed a significant interaction between participants' performance and time effect in the left inferior frontal cortex. Our results provide the first evidence of this cerebral area being involved in the processing of contextual information in a probabilistic sequence learning task.SCOPUS: cp.jinfo:eu-repo/semantics/published9e Congrès TENNET :Theoretical and Experimental Neuropsychology, Montréal, Canada 10 June 199

A Description Of Chrondrodystrophy In 3 Poultry Units Producing Labeled Chickens.

The present paper describes chondrodystrophy (perosis) in three poultry units producing labelled chickens. An unilateral deviation of a hind leg along with a tumefaction of the tarsal joint appeared in 4-day- to 4-week-old birds; 5 to 50% of the animals were affected. The growth rate was reduced and cachexia was also observed. There were also breast blisters. Chemical analyses were carried out on the poultry feed in two of the units. The manganese content was below the requirements at about 35 mg/kg; in one unit, the ionic balance (Na+K-Cl) was insufficient along with a too narrow Ca/P. The insufficient supply in manganese was corrected by the addition of manganese sulfate in water at a rate of 120 g/litre of water. Manganese sulfate was also added in the feedstuff at a rate of 120 g/ton

Processing of contextual information during an implicit probabilistic sequence learning task: Left ventrolateral prefrontal cortex involvement

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Striatum forever, despite sequence learning variability: A random effect analysis of PET data

This PET study is concerned with the what, where, and how of implicit sequence learning. In contrast with previous studies imaging the serial reaction time (SRT) task, the sequence of successive locations was determined by a probabilistic finite-state grammar. The implicit acquisition of statistical relationships between serially ordered elements (i.e. what) was studied scan by scan, aiming to evidence the brain areas (i.e. where) specifically involved in the implicit processing of this core component of sequential higher-order knowledge. As behavioural results demonstrate between- and within-subjects variability in the implicit acquisition of sequential knowledge through practice, functional PET data were modelled using a random-effect model analysis (i.e. how) to account for both sources of behavioural variability. First, two mean condition images were created per subject depending on the presence or not of implicit sequential knowledge at the time of each of the 12 scans. Next, direct comparison of these mean condition images provided the brain areas involved in sequential knowledge processing. Using this approach, we have shown that the striatum is involved in more than simple pairwise associations and that it has the capacity to process higher-order knowledge. We suggest that the striatum is not only involved in the implicit automatization of serial information through prefrontal cortex-caudate nucleus networks, but also that it plays a significant role for the selection of the most appropriate responses in the context created by both the current and previous stimuli, thus contributing to better efficiency and faster response preparation in the SRT task. Hum. Brain Mapping 10:179–194, 2000. © 2000 Wiley-Liss, Inc.FLWINinfo:eu-repo/semantics/publishe

Infectious laryngotracheitis: a review

Infectious laryngotracheitis (ILT) herpesvirus continues to cause outbreaks of respiratory disease in chickens world-wide. Sporadic cases of ILT occur in all classes of birds, including hobby/show/game chickens, broilers, heavy breeders, and commercial laying hens. These epornitics of ILT tend to occur where there are large populations of naïve, unvaccinated birds, i.e., in concentrated areas of broiler production. ILT virus can be transmitted through (a) chickens with acute upper respiratory tract disease, (b) latently infected "carrier" fowls, and (c) fomites and contaminated persons. Chicken flocks which are endemic infected with ILT virus occur only in some regions of countries or even in particular multiple-age production farms. In these cases modified live vaccines are actually used, even though these biological products, as well as wild ILTV strains, can establish latent infections. In the case of heavy breeders and laying hens, which are typically vaccinated against ILT, sporadic cases are often related to errors in vaccine application and to biosecurity failures