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Sensory integration theory predicts natural selection should favour adaptive responses of animals to multiple forms of information, yet empirical tests of this prediction are rare, particularly in free-living mammals. Studying indirect predator cues offers a salient opportunity to inquire about multimodal risk assessment and its potentially interactive effects on prey responses. Here we exposed California ground squirrels from two study sites (that differ in human and domestic dog activity) to acoustic and/or olfactory predator cues to reveal divergent patterns of signal dominance. Olfactory information most strongly predicted space use within the testing arena. That is, individuals, especially those at the human-impacted site, avoided coyote urine, a danger cue that may communicate the proximity of a coyote. By contrast, subjects allocated less time to risk-sensitive behaviours when exposed to acoustic cues. Specifically, although individuals were consistent in their behavioural responses across trials, 'quiet coyotes' (urine without calls) significantly increased the behavioural reactivity of prey, likely because coyotes rarely vocalize when hunting. More broadly, our findings highlight the need to consider the evolution of integrated fear responses and contribute to an emerging understanding of how animals integrate multiple forms of information to trade off between danger and safety cues in a changing world. [ABSTRACT FROM AUTHOR]

Sensory integration theory predicts natural selection should favour adaptive responses of animals to multiple forms of information, yet empirical tests of this prediction are rare, particularly in free-living mammals. Studying indirect predator cues offers a salient opportunity to inquire about multimodal risk assessment and its potentially interactive effects on prey responses. Here we exposed California ground squirrels from two study sites (that differ in human and domestic dog activity) to acoustic and/or olfactory predator cues to reveal divergent patterns of signal dominance. Olfactory information most strongly predicted space use within the testing arena. That is, individuals, especially those at the human-impacted site, avoided coyote urine, a danger cue that may communicate the proximity of a coyote. By contrast, subjects allocated less time to risk-sensitive behaviours when exposed to acoustic cues. Specifically, although individuals were consistent in their behavioural responses across trials, 'quiet coyotes' (urine without calls) significantly increased the behavioural reactivity of prey, likely because coyotes rarely vocalize when hunting. More broadly, our findings highlight the need to consider the evolution of integrated fear responses and contribute to an emerging understanding of how animals integrate multiple forms of information to trade off between danger and safety cues in a changing world. [ABSTRACT FROM AUTHOR]

Adolescent non-suicidal self-injury (aNSSI) is associated with abnormal scores on personality traits, such as high neuroticism. However, no studies to date have examined personality facets of self-injury in a cohort younger than college-age. Plus, adolescent psychopathologies, especially Depressive Disorders, are associated with a similar personality profile and are highly comorbid with aNSSI. Consequently, it remains unclear whether personality provides insights about aNSSI in youth beyond that due to underlying psychopathology. 550 community-dwelling 13- to 15-year-old never-depressed adolescent girls were interviewed for lifetime aNSSI and lifetime psychopathology. Personality traits, broad domains and specific facets, were assessed by self-report. Never-depressed adolescent girls who endorse aNSSI often met lifetime criteria for psychiatric disorders (NSSI: 20/43; 46.5% vs. non-aNSSI: 131/507; 26.1%). aNSSI and lifetime psychopathology were each independently associated with several traits (e.g., high neuroticism and conscientiousness), whereas some traits only discriminated aNSSI (e.g., high melancholia, a facet of neuroticism related to sadness and negative self-evaluation) or lifetime psychopathology independent of each other (e.g., low positive emotionality; low agreeableness). Furthermore, a multivariate model identified high melancholia, high openness to experience, and low conscientiousness as incrementally independent correlates of lifetime aNSSI over and above psychiatric illness. Proneness to melancholia, interest in new things, and poor self-control incrementally track aNSSI in never-depressed adolescent girls. Importantly, this emerges early in course (13-15 years of age) and is independent of lifetime psychiatric diagnosis. Implications for updating etiological models and clinical utility of personality assessment are discussed. [ABSTRACT FROM AUTHOR]

Purpose: To compare image quality including the number of perforators visualized, vessel contrast ratios, and vessel sharpness with blood pool and extracellular contrast agents in abdominal perforator flap magnetic resonance angiography (MRA). Materials and Methods: Preoperative perforator flap MRA was performed prone on 64 consecutive patients undergoing breast reconstruction (32 receiving 20 mL gadobenate dimeglumine and 32 receiving 10 mL gadofosveset trisodium) on transverse 3D fat-suppressed spoiled gradient echo images using high spatial resolution. Image quality was assessed qualitatively on a 4-point scale. On a computer workstation the number of perforators visualized was counted, arterial, venous, muscle, fat, and abdominal perforator signal intensities were measured to calculate signal intensity and contrast ratios, and vessel sharpness was evaluated. Results: The qualitative image quality score was higher for gadofosveset (2.7) than gadobenate (2.0) and CTA (2.0). The mean number of perforators visualized with gadofosveset was 6.8 on right and 10.4 on left compared to 4.6 on right and 6.6 on left for gadobenate ( P < 0.0001). The artery-to-fat contrast ratio was comparable, suggesting the difference was not related to magnitude of enhancement. Perforator-to-muscle contrast ratio was greater for gadofosveset, 2.3, compared to gadobenate 1.5 ( P = 0.002). Vessel sharpness was also greater for gadofosveset ( P = 0.006). Conclusion: Perforator MRA image quality including number of perforators visualized, perforator-to-muscle contrast, and vessel sharpness is higher with gadofosveset trisodium compared with gadobenate dimeglumine. J. Magn. Reson. Imaging 2012;35:711-716. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Natural selection is expected to favor the evolution of threat-sensitive behaviors that permit individuals to adaptively detect and respond to danger. However, because time allocated to vigilance reduces the amount of time that is available for energy acquisition, foraging in the face of predation can impose an evolutionary trade-off. Optimal foraging theory therefore predicts that risk-taking decisions should vary in response to perceived levels of threat. Our goal here is to disentangle the relative contributions of conspecific presence, ecological factors, and individual traits on two measures of vigilance in free-living California ground squirrels (Otospermophilus beecheyi). This facultatively social and ecologically flexible rodent represents a major source of prey in California grasslands. Over a 5-year period, we collected 386 focal animal surveys on 156 free-living individuals residing at two colony sites. Individuals were most vigilant in conditions for which predation risk was highest, such as when foraging alone and on flat areas with low vegetative cover. In general, juvenile foragers were more gregarious but less vigilant than adult foragers. Although all animals—regardless of age or sex—generally decreased their intensity of vigilance as group size increased, only adults decreased their time allocated to vigilance in response to conspecific presence. Thus, grouping consistently buffered the costs of foraging for risk-averse adults, but the benefits of conspecific presence were less salient for juveniles. Taken together, our findings highlight the importance of context in shaping foraging decisions and offer insights into the suite of factors mediating decision-making in socially and ecologically variable environments. Significance statement: Animals face trade-offs when foraging in the face of predation, but the capacity for individuals to respond appropriately to subtle changes in context-dependent threats remains poorly understood. We studied antipredator vigilance by the California ground squirrel, a flexible species that may forage alone or in small groups of various sizes and in habitats that vary in their protective value from predators and the ease at which prey may detect predators. Although adults are more sensitive to changes in group size, all animals detected context-dependent danger to some extent. Our findings offer insights into the multiple factors that prey respond to when making foraging decisions, suggesting that animals possess the ability to integrate disparate sources of information about danger to optimize energy gain. [ABSTRACT FROM AUTHOR]