Whether timing affects contingency learning is currently poorly understood. Specifically, does temporal predictability aid the acquisition of contingencies? We asked participants in a music contingency learning task to respond to the target (the name of a note) while ignoring tones. To assess whether temporal predictability influences the acquisition of these contingencies, we manipulated the temporal context of tone presentation in two experiments. In Experiment 1, one group of participants listened to tones presented with a regular temporal interval (1000 ms between each trial), while the other group listened to tones presented in a random manner (random intervals selected between 600 and 1400 ms). In Experiment 2 we manipulated the temporal presentation of the tones within trials: one group listened to tones with a 300 ms fixed interval between the cue and the target, and the other group with an interval randomly selected between 0 and 600 ms. Although participants learned to associate pitch labels in both experiments this occurred independently of the timing manipulations. These results confirm prior evidence on contingency learning but do not show the effects of temporal predictability in this learning context.

When livestock are killed by predators, circumstantial evidence is often the only information available to determine which predator species made the kill. Evidence can consist of rake marks, scat, hair, attack points, tracks, sightings, and canine punctures. Canine punctures in particular can be informative because they offer the most direct evidence of attack, particularly if they are linked to tissue hemorrhaging. When investigating canine punctures, a common technique to identify the predator species is to measure the canine cusp spread for maxillary and mandibular tips as measured from the maxillary to maxillary tip or mandibular to mandibular tip. The assumption is that different predator species will have different and distinct canine spread. Surprisingly, little has been published on canine spread and comparing different carnivore species, leaving wildlife managers unable to reliably use this technique for predator identification. During 2008, we started a project to assess the width of canine spread in carnivores. The majority of information gathered to date shows a narrow range of measurements for coyotes and broad variation in feral/free ranging dogs that can overlap coyote measurements. The information provided on scientifically measured canine spread will assist the wildlife damage manager in determining the actual predatory species, especially when used with additional evidence gathered on site.

This letter addresses the controversial issue of the use of oral corticosteroids during wheezing exacerbations in preschool-aged children by demonstrating findings of a prematurely terminated multi-center clinical trial, discussing lessons learned, and suggesting future directions.