668 research outputs found
The Effects of Cognitive Heuristics on Strategic Action: Overcoming the Risk Hurdles to First Move
This article theorizes that underestimating the risks of first moving may actually enhance performance if entrepreneurs have a learning orientation, the organization is flexible, and the environment is benevolent
When It's Right to be "Wrong": The Effects of Overconfidence and Planning on Product Performance in a Dynamic Environment
Some authors emphasize overconfidence may benefit managers by increasing decision-making efficiency, whereas others argue it results in serious errors. This study helps resolve the debate by examining the relationship between overconfidence and product performance, as well as testing whether planning might mediate the link. The study sampled 52 small computer companies that had decided to introduce a product. It examined the manager's overconfidence and planning when the product was launched and measured the product's performance 18 months later. We found that overconfidence decreased planning, planning decreased performance, and, as hypothesized, planning mediated the relationship between the two other variables. By examining the meditating role of planning, we were able to better identify the causal relationships and clarify the effects of overconfidence
Tracing carbon flow through coral reef food webs using a compound-specific stable isotope approach
Author Posting. Ā© The Author(s), 2015. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Oecologia 180 (2016): 809-821, doi:10.1007/s00442-015-3475-3.Coral reefs support spectacularly productive and diverse communities in tropical and sub26
tropical waters throughout the worldās oceans. Debate continues, however, on the degree to
which reef biomass is supported by new water column production, benthic primary production,
and recycled detrital carbon. We coupled compound-specific Ī“13C analyses with Bayesian
mixing models to quantify carbon flow from primary producers to coral reef fishes across
multiple feeding guilds and trophic positions in the Red Sea. Analyses of reef fishes with
putative diets composed primarily of zooplankton (Amblyglyphidodon indicus), benthic
macroalgae (Stegastes nigricans), reef-associated detritus (Ctenochaetus striatus), and coral
tissue (Chaetodon trifascialis) confirmed that Ī“13C values of essential amino acids from all
baseline carbon sources were both isotopically diagnostic and accurately recorded in consumer
tissues. While all four source end-members contributed to the production of coral reef fishes in
our study, a single source end-member often dominated dietary carbon assimilation of a given
species, even for highly mobile, generalist top predators. Microbially-reworked detritus was an
important secondary carbon source for most species. Seascape configuration played an important
role in structuring resource utilization patterns. For instance, L. ehrenbergii, showed a significant
shift from a benthic macroalgal food web on shelf reefs (71 Ā± 13% of dietary carbon) to a
phytoplankton-based food web (72 Ā± 11%) on oceanic reefs. Our work provides insights into the
roles that diverse carbon sources play in the structure and function of coral reef ecosystems and
illustrates a powerful fingerprinting method to develop and test nutritional frameworks for
understanding resource utilization.This research was based on work supported by Awards USA 00002 and KSA 00011 from King Abdullah University of Science and Technology (KAUST); additional funding was provided by the Woods Hole Oceanographic Institution (WHOI), a KAUST-WHOI award (SPCF-7000000104), and KAUST baseline research funds.2016-11-2
The Conceptual and Methodological Mayhem of "Screen Time".
Debates concerning the impacts of screen time are widespread. Existing research presents mixed findings, and lacks longitudinal evidence for any causal or long-term effects. We present a critical account of the current shortcomings of the screen time literature. These include poor conceptualisation, the use of non-standardised measures that are predominantly self-report, and issues with measuring screen time over time and context. Based on these issues, we make a series of recommendations as a basis for furthering academic and public debate. These include drawing on a user-focused approach in order to seek the various affordances gained from "screen use". Within this, we can better understand the way in which these vary across time and context, and make distinction between objective measures of "screen time" compared to those more subjective experiences of uses or affordances, and the differential impacts these may bring
Adolescents' longitudinal trajectories of mental health and loneliness: the impact of COVID-19 school closures
INTRODUCTION: Longitudinal research examining the impact of coronavirus disease 2019 (COVIDā19) school closures on the mental health of adolescents is scarce. Prolonged periods of physical and social isolation because of such restrictions may have impacted heavily on adolescentsā mental health and loneliness. METHODS: The current study addresses a major gap by examining the impact of school closures on the mental health and loneliness of 785, 10ā to 17āyearāold Western Australian adolescents (mean ageā=ā14.1, SDā=ā1.31), who were surveyed across four time points: twice before COVIDā19, once as schools closed, and once post reopening of schools. Preā and postāCOVIDā19 changes in mental health and loneliness were compared using linear mixed models. Random intercept crossālagged panel models (RIāCLPMs) assessed temporal associations between loneliness, depression symptoms, and positive mental wellbeing. RESULTS: Compared with preāCOVIDā19 symptom levels, there were significant increases in depression symptoms, internalizing and externalizing symptoms, and a significant decrease in positive mental wellbeing at different points over time. Symptom change over time differed according to gender and preāCOVIDā19 symptom severity. Significant increases in positive attitudes towards being alone and feelings of isolation occurred at different points over time. Gender differences were evident. RIāCLPMs highlighted the predictive significance of friendship quality and having a negative attitude towards being alone over time in relation to depression symptoms. A positive or negative attitude towards being alone was predictive of positive mental wellbeing over time. CONCLUSION: Findings provide evidence that COVIDā19ārelated school closures adversely affected adolescents' mental health and feelings of loneliness
Stable isotope analyses of feather amino acids identify penguin migration strategies at ocean basin scales
Author Posting. Ā© The Author(s), 2017. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Biology Letters 13 (2017): 20170241, doi:10.1098/rsbl.2017.0241.Identifying the at-sea distribution of wide ranging 20 marine predators is critical to
understanding their ecology. Advances in electronic tracking devices and intrinsic
biogeochemical markers have greatly improved our ability to track animal movements on ocean-wide scales. Here we show that, in combination with direct tracking, stable carbon isotope
analysis of essential amino acids in tail feathers provides the ability to track the movement
patterns of two, wide-ranging penguin species over ocean basin scales. In addition, we use this
isotopic approach across multiple breeding colonies in the Scotia Arc to evaluate migration
trends at a regional scale that would be logistically challenging using direct tracking alone.Funded by the National Marine Sanctuary Foundation (GLS tags), Ocean Life Institute
(M.J.P, L.H., S.R.T), Darwin Initiative (T.H.), and SeaWorld Bush Gardens Conservation Fund
(M.J.P, S.R.T)
Stable isotope analyses of feather amino acids identify penguin migration strategies at ocean basin scales
Identifying the at-sea distribution of wide-ranging marine predators is critical to understanding their ecology. Advances in electronic tracking devices and intrinsic biogeochemical markers have greatly improved our ability to track animal movements on ocean-wide scales. Here, we show that, in combination with direct tracking, stable carbon isotope analysis of essential amino acids in tail feathers provides the ability to track the movement patterns of two, wide-ranging penguin species over ocean basin scales. In addition, we use this isotopic approach across multiple breeding colonies in the Scotia Arc to evaluate migration trends at a regional scale that would be logistically challenging using direct tracking alone.Facultad de Ciencias Naturales y Muse
Development of the Perth Adolescent Worry Scale (PAWS)
Tools to assess worry among adolescents exist but do not capture the content of worries. This study reports on the development of a brief, psychometrically sound measure of worry for use with adolescents. Phase 1 involved identification of 27 potential items from existing instruments as well as item generation identified in interviews with students, teachers, school psychologists, and parents. In Phase 2, the candidate items were completed by 835 Australian adolescents (317 males, 508 females, 10 unspecified; Mean age = 13.55, SD = 1.31) from Grades 5 to 10. These data were randomly split in half, and an exploratory factor analysis on the first half identified a two-factor solution with 12 items: Peer Relationships (6 items) and Academic Success and the Future (6 items). On the second half of the data, confirmatory factor analyses supported the factor structure and supported strong invariance across age, socioeconomic status, and presence/absence of a diagnosed neurodevelopmental disorder. Weak invariance was evident across sex. Differences across groups are reported as are correlations with indicators of psychological wellbeing. In conclusion, the Perth Adolescent Worry Scale provides both applied professionals and researchers with a short, easy-to-administer, and psychometrically strong instrument to evaluate adolescentsā everyday worries
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