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The authors examined how neuropsychological, personality, and environmental risk factors and their interactions were related to trajectories of delinquent behavior from adolescence to adulthood. Four waves of longitudinal data from 698 male participants, ages 12-18 at Time 1 and ages 25-31 at Time 4, were included in the analyses. Using a growth mixture(More)
When searching for prey, big brown bats (Eptesicus fuscus) enhance the range of their sonar by concentrating more energy in the nearly constant-frequency (CF) tail portion of their frequency-modulated (FM) sweeps. We hypothesize that this portion of their signals may be vulnerable to interference from conspecifics using the same frequencies in their own(More)
When echolocating big brown bats fly in complex surroundings, echoes arriving from irrelevant objects (clutter) located to the sides of their sonar beam can mask perception of relevant objects located to the front (targets), causing "blind spots." Because the second harmonic is beamed more weakly to the sides than the first harmonic, these clutter echoes(More)
Sonar broadcasts are followed by echoes at different delays from objects at different distances. When broadcasts are emitted rapidly in cluttered surroundings, echo streams from successive broadcasts overlap and cause ambiguity in matching echoes to corresponding broadcasts. To identify reactions to ambiguity in clutter, echolocating bats that emit(More)
Big brown bats emit FM biosonar sounds containing two principal harmonics (FM1 approximately 55-22 kHz;FM2 approximately 105-45 kHz). To examine the role of harmonics, they were selectively filtered from stimuli in electronic-echo delay discrimination experiments. Positive stimuli were delayed by 3.16 ms (55 cm simulated target range); negative stimuli were(More)
Analysis of acoustic interactions between animals in active choruses is complex because of the large numbers of individuals present, their high calling rates, and the considerable numbers of vocalizations that either overlap or show close temporal alternation. The authors describe a methodology for recording chorus activity in bullfrogs (Rana catesbeiana)(More)
A multiple sensor array was employed to identify the spatial locations of all vocalizing male bullfrogs (Rana catesbeiana) in five natural choruses. Patterns of vocal activity collected with this array were compared with computer simulations of chorus activity. Bullfrogs were not randomly spaced within choruses, but tended to cluster into closely spaced(More)
Human rhinovirus (HRV)-induced respiratory infections are associated with elevated levels of IFN-gamma-inducible protein 10 (IP-10), which is an enhancer of T lymphocyte chemotaxis and correlates with symptom severity and T lymphocyte number. Increased IP-10 expression is exhibited by airway epithelial cells following ex vivo HRV challenge and requires(More)
This study examines self-attributed consequences of cocaine use in a nonclinical sample of 1,270 young adults. A social learning perspective was used to examine the ability of motivational dimensions of use, as well as use patterns, to predict negative consequences of use. Four scales of negative consequences emerged: Negative Effects, Dependency Symptoms,(More)