399 research outputs found

    Resource Use by American Black Bears in Suburbia: A Landholder Step Selection Approach

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    Range expansion of American black bears (Ursus americanus; bear) and residential development have increased the bear presence in suburbia. Suburban landscapes exhibiting patchworks of variable-sized parcels and habitats and owned by landowners with diverse values can create large areas of suitable habitats with limited public access. These landscapes may limit the effectiveness of hunting as a traditional bear population management tool. Managers require better information regarding landowner attitudes about hunting before implementing harvest regulations intended to mitigate conflicts in suburban areas. To address this need, in 2013, we surveyed landowners to identify properties that allowed bear hunting in 3 suburban areas of Pennsylvania, USA where bear sightings or human–bear conflicts have increased. We then used location data obtained for 29 bears equipped with global positioning system transmitters from 2010 to 2012 to model their resource selection in the study area. We assessed the influence of hunting access, housing density, land cover, and topographic variables on radio-marked black bears monitored 10 days before, during, and after the bear hunting season. We found that resource selection of radio-marked bears was similar for all 3 periods and bears selected for forested land in all 3 seasons and herbaceous cover in the pre-hunting and hunting periods. Resource selection by bears was not influenced by hunting access in the pre-hunting and hunting periods. For the post-hunting period, lands closed to hunting had support as the second-best model. All of the radio-marked bears in our study were vulnerable to harvest. However, they did not change resource selection during the hunting season, nor did they avoid areas open to hunting. Integrating human dimension data with bear habitat use studies, especially in suburban landscapes, has the potential to address bear space use and population management needs often overlooked by traditional research designs

    Welfare Performance of Three Foothold Traps for Capturing North American River Otters \u3ci\u3eLontra canadensis\u3c/i\u3e

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    Foothold traps are effective tools for the live capture and restraint of wildlife for management and research. Successful river otter Lontra canadensis restoration programs throughout North America used them extensively. Restoration programs used a variety of methods and models of foothold traps, but comprehensive efforts to describe and quantify injuries associated with river otter captures have been limited. We evaluated injuries of river otters caught in three commercially available models of foothold traps including the number 11 double long-spring with standard jaws, the number 11 double long-spring with double jaws, and the number 2 coil-spring trap. Based on examinations of 70 captured river otters, we classified 78% of the total inj uries detected as ‘‘mild’’ (n=174 injuries) and 17% were classified as ‘‘moderate’’ (n= 37 injuries). We classified less than 3% of the injuries observed as ‘‘moderately severe’’ or ‘‘severe.’’ We focused only on the animal welfare performance of traps; the three trap types we tested met the animal welfare criteria required for inclusion in the best management practices for trapping river otter. The criteria based on International Standards Organization guidelines used in this assessment of trap performance provides a scientific basis for future evaluations of river otter welfare when foothold traps are used for restoration, research, and population management

    A systematic review of physiological reactivity to stimuli in autism

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    Objective: The prevalence of abnormal behavioural responses to a variety of stimuli among individuals with autism has led researchers to examine whether physiological reactivity is typical in this population. The current paper reviewed studies assessing physiological reactivity to sensory, social and emotional, and stressor stimuli in individuals with autism. Methods: Systematic searches of electronic databases identified 57 studies that met our inclusion criteria. A novel measure of methodological quality suitable for use with non-randomised, non-interventional, psychophysiological studies was also developed and applied. Results: Individuals with autism were found to respond differently than typically developing controls in 78.6%, 66.7%, and 71.4% of sensory, social and emotional, and stressor stimulus classes, respectively. Conclusions: Individual differences in physiological reactivity are clearly present in autism, suggesting additional research is needed to determine the variables relating to physiological reactivity among those with ASD and to examine the possibility of physiological subtype responders in this population

    Metabolically exaggerated cardiac reactions to acute psychological stress: The effects of resting blood pressure status and possible underlying mechanisms

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    The study aimed to: confirm that acute stress elicits metabolically exaggerated increases in cardiac activity; test whether individuals with elevated resting blood pressure show more exaggerated cardiac reactions to stress than those who are clearly normotensive; and explore the underlying mechanisms. Cardiovascular activity and oxygen consumption were measured pre-, during, and post- mental stress, and during graded submaximal cycling exercise in 11 young men with moderately elevated resting blood pressure and 11 normotensives. Stress provoked increases in cardiac output that were much greater than would be expected from contemporary levels of oxygen consumption. Exaggerated cardiac reactions were larger in the relatively elevated blood pressure group. They also had greater reductions in total peripheral resistance, but not heart rate variability, implying that their more exaggerated cardiac reactions reflected greater β-adrenergic activation

    On de-bunking “Fake News” in the post-truth era : how to reduce statistical error in research

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    The authors note with alarm that statistical noise caused by statistical incompetence is beginning to creep into research on cost overrun in public investment projects, contaminating research with work that does not meet basic standards of validity and reliability. The paper gives examples of such work and proposes three heuristics to root out the problem. First, researchers who are not statisticians, or do not have a strong background in statistics, should abstain from doing statistical analysis, and instead rely on more experienced colleagues, preferably professional statisticians. Second, journal referees should clearly state their level of statistical proficiency to journal editors, so these can set the right referee team. Finally, journal editors should make sure that at least one referee is capable of reviewing the statistical and methodological aspects of a paper. The work under review would have benefitted from observing these simple heuristics, as would any work based on statistical analysis.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Transport and Logistic

    The Affective Impact of Financial Skewness on Neural Activity and Choice

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    Few finance theories consider the influence of “skewness” (or large and asymmetric but unlikely outcomes) on financial choice. We investigated the impact of skewed gambles on subjects' neural activity, self-reported affective responses, and subsequent preferences using functional magnetic resonance imaging (FMRI). Neurally, skewed gambles elicited more anterior insula activation than symmetric gambles equated for expected value and variance, and positively skewed gambles also specifically elicited more nucleus accumbens (NAcc) activation than negatively skewed gambles. Affectively, positively skewed gambles elicited more positive arousal and negatively skewed gambles elicited more negative arousal than symmetric gambles equated for expected value and variance. Subjects also preferred positively skewed gambles more, but negatively skewed gambles less than symmetric gambles of equal expected value. Individual differences in both NAcc activity and positive arousal predicted preferences for positively skewed gambles. These findings support an anticipatory affect account in which statistical properties of gambles—including skewness—can influence neural activity, affective responses, and ultimately, choice

    Psychophysiological measures of stress in caregivers of individuals with autism spectrum disorder: a systematic review

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    Purpose: Parents of children with autism spectrum disorder (ASD) often self-report heightened levels of stress and physical health problems. This paper reviewed studies assessing physiological measures of stress among parents of children with ASD. Methods: Systematic database searches identified 15 studies meeting inclusion criteria. Studies were reviewed to determine: (a) control group characteristics; (b) caregiver and care recipient characteristics; (c) setting; (d) physiological measures employed; (e) physiological outcomes; and (f) stressor type. A measure of methodological quality was also applied. Results: Salivary cortisol was the most common physiological measure employed. A pattern of blunted physiological activity emerged within the reviewed studies, though some studies reported normal or even higher physiological activity among this population. Conclusions: Findings suggested dysfunction of the hypothalamic-pituitary-adrenal-axis and autonomic nervous system for some, but not all, parents of children with ASD. Further research is warranted

    When the going gets tough: Employee reactions to large‐scale organizational change and the role of employee Machiavellianism

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    Large-scale, long-term change initiatives take time to unfold, which can be a source ofuncertainty and strain. Investigating the initial 19 months of a large-scale change, weargue that during these stages, employees' change-related beliefs become more negativeover time, which negatively affects their work engagement and, ultimately, increasestheir turnover intentions. Furthermore, we investigate the impact of a trait, Machiavel-lianism, on change reactions and propose that employees high in Machiavellianism reactmore negatively during change processes as they are especially susceptible to uncer-tainty and stress. We test our (cross-level) moderated mediation model in a three-wavelongitudinal study among employees undergoing a large-scale change (T1: n = 1,602; T2:n =1,113;T3:n = 759). We find that employees' beliefs about the impact and value ofthe change are indeed negatively related to change duration and that decreases in theseperceptions come with a decline in engagement and increases in turnover intentions.Moreover, employees high in Machiavellianism react more strongly to a deterioration inchange-related beliefs, showing stronger reductions in engagement and strongerincreases in turnover intentions than employees low in Machiavellianism. Our studyoffers explanations for the negative effects of large-scale changes including an explana-tory factor for disparate employee reactions to change over time
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