Published by Elsevier B.V.”
“Patients with basal ganglia (BG) pathology are consistently found to be impaired on rule-based category learning tasks in which learning is thought to depend upon the use of an explicit, hypothesis-guided strategy. The factors that influence this impairment remain Barasertib unclear. Moreover, it remains unknown if the impairments observed in patients with degenerative disorders such as Parkinson’s disease (PD) are also observed in those with focal BC lesions. In the present study, we tested patients with either focal BC lesions or PD on two categorization tasks that varied in terms of their demands on selective

attention and working memory. Individuals with focal BG lesions were impaired on the task in which working memory demand was high and performed similarly to healthy controls on the task in which Selleckchem A-1210477 selective-attention demand was high. In contrast, individuals with PD were impaired on both tasks, and accuracy rates did not differ between on and off medication states for a subset of patients who were also tested after abstaining from dopaminergic medication. Quantitative, model-based analyses attributed the performance deficit for both groups in the task with high working memory demand to the utilization of suboptimal strategies,

whereas the PD-specific impairment on the task with high selective-attention demand was driven by the inconsistent use of an optimal strategy. These data suggest that the demands on selective attention and working memory affect the presence of impairment in patients with focal BC lesions and the nature of the impairment in patients with PD. (C) 2010 Elsevier Ltd. All rights reserved.”
“A mathematical model was developed to predict the viability of airborne viruses. The model uses water activity as the primary independent variable and an exponential decay function for the viability of the virus. This model was tested using published experimental data obtained by different investigators for influenza. Langat and polio viruses.

The aerosolized media were modelled as a binary solution of water and sodium chloride. The water activity is related directly to the solute concentration in the binary solution. The minimum viability usually occurred just above the efflorescence point, which is the relative humidity at which Flavopiridol (Alvocidib) the solution crystallizes. The relationship between water activity and relative humidity is based on the Kohler theory, whereby the Kelvin term was taken into account. Physical explanations are provided on the variation of viral viability at different relative humidity levels. The predictions obtained by the proposed mathematical model compare well with most of the published experimental data. (C) 2009 Elsevier B.V. All rights reserved.”
“There has recently been a resurgence in the idea that amnesia may be characterized by an increased susceptibility to interference.