Who should be searching? Differences in personality can affect visual search accuracy

© 2017 Visual search is an everyday task conducted in a wide variety of contexts. Some searches are mundane, such as finding a beverage in the refrigerator, and some have life-or-death consequences, such as finding improvised explosives at a security checkpoint or within a combat zone. Prior work has shown numerous influences on search, including “bottom-up” (physical stimulus attributes) and “top-down” factors (task-relevant or goal-driven aspects). Recent work has begun to focus on “observer-specific” factors, examining how searchers' attributes might influence search performance. A logical extension involves exploring whether some individuals are better suited to conduct visual searches than other individuals. The current study examined whether certain personality characteristics relate to visual search performance in a large sample of professional searchers employed by the U.S. Transportation Security Administration. Of the “big five” personality traits (neuroticism, extroversion, openness, agreeableness, and conscientiousness), only conscientiousness significantly correlated with visual search accuracy. Both early-career and experienced professional searchers demonstrated a significant relationship between conscientiousness scores and accuracy on a simple visual search task. These findings validate the notion that searchers' attributes impact their visual search performance and suggest that personality assessments might prove useful for hiring and selection decisions regarding professional tasks that incorporate visual search

Sleep disturbance at pre-deployment is a significant predictor of post-deployment re-experiencing symptoms.

Background: Insomnia is common in service members and associated with many mental and physical health problems. Recently, longitudinal data have been used to assess the impact of disturbed sleep on mental health outcomes. These studies have consistently shown relationships between sleep disturbance and development of mental illness. Objective: The present study examined the longitudinal relationship between sleep disturbance and PTSD symptomatology in a cohort of Marines and Navy Corpsmen deployed to Iraq and Afghanistan (n = 2,404) assessed prior to deployment, as well as at -3 and 6 months post-deployment. Additionally, we aimed to investigate the extent to which these relationships are moderated by combat-stress severity, and to what extent these findings are replicated in a second, separate cohort of Marines and Navy corpsmen (n = 938) assessed with identical measures prior to deployment and within 3 months of return. Method: The present study employed latent variable path models to examine the relationships between pre-deployment sleep disturbance and post-deployment re-experiencing symptoms. Initial cross-lagged path models were conducted on discovery and replication samples to validate the hypothesized predictive relationships. Follow up moderation path models were then conducted to include the effect of combat-stress severity on these relationships. Results: Initial cross-lagged models supported a significant relationship between pre-deployment sleep disturbance and future re-experiencing PTSD symptoms at all time points. Initial moderation models showed a small moderator effect of combat-stress severity, though the main predictive relationship between pre-deployment sleep disturbance and PTSD symptoms remained significant. The moderator effect was not significant in the replication sample. Conclusions: The results of this study support pre-deployment sleep disturbance as a risk factor for development of post-deployment PTSD symptoms. Interventions aimed at normalizing sleep may be important in preventive measures for PTSD

Lattice study of ChPT beyond QCD

We describe initial results by the Lattice Strong Dynamics (LSD) collaboration of a study into the variation of chiral properties of chiral properties of SU(3) Yang-Mills gauge theory as the number of massless flavors changes from $N_f = 2$ to $N_f = 6$, with a focus on the use of chiral perturbation theory.Comment: 9 pages, 3 figures. Presented at the 6th International Workshop on Chiral Dynamics, University of Bern, Switzerland, July 6-10 200

Toward TeV Conformality

We study the chiral condensate $$ for an SU(3) gauge theory with $N_f$ massless Dirac fermions in the fundamental representation when $N_f$ is increased from 2 to 6. For $N_f=2$, our lattice simulations of $<\bar{\psi} \psi >/F^3$, where $F$ is the Nambu-Goldstone-boson decay constant, agree with the measured QCD value. For $N_f = 6$, this ratio shows significant enhancement, presaging an even larger enhancement anticipated as $N_f$ increases further, toward the critical value for transition from confinement to infrared conformality.Comment: 4 pages, 4 figures. v2: revised version for PR

Construction of bosonic string theory on infinitely curved Anti-de Sitter space

Free scalar field theory in the sector with a large number of particles can be interpreted as bosonic string theory on anti-de Sitter space of vanishing radius. Different ways of writing the field theory Hamiltonian translate to different ways of reparametrizing the world-sheet sigma coordinate. Adding a mass term in the field theory corresponds to cutting off the warped AdS direction, with cut-off inversely proportional to the mass. The string theory has neither tachyon, nor critical dimension.Comment: 18 pages, latex, using revte

Social Desirability and the Celebrity Attitude Scale

The possibility of social desirability bias has often been neglected in the construction and evaluation of attitudinal scales and personality inventories in psychology and related disciplines. The present study aimed to explore the potential influence of such biases on respondents’ self-reported celebrity worship. Specifically, we had a student sample (n = 187) complete a) measures of two different forms of social desirability bias (externally-oriented “Impression management” vs. internally-oriented “self-deceptive positivity”) and b) the Celebrity Attitude Scale (CAS). Results showed that neither measure correlated significantly with the CAS. Furthermore, neither gender nor delivery mode (online vs. paper-and-pencil) mediated the non-significant relationships. Our results add to the confidence researchers might have in using this tool to measure attitudes toward one’s favorite celebrity. Other results are generally consistent with previous studies using the CAS

The recovery of plant community composition following passive restoration across spatial scales

Human impacts have led to dramatic biodiversity change which can be highly scale-dependent across space and time. A primary means to manage these changes is via passive (here, the removal of disturbance) or active (management interventions) ecological restoration. The recovery of biodiversity, following the removal of disturbance, is often incomplete relative to some kind of reference target. The magnitude of recovery of ecological systems following disturbance depends on the landscape matrix and many contingent factors. Inferences about recovery after disturbance and biodiversity change depend on the temporal and spatial scales at which biodiversity is measured. We measured the recovery of biodiversity and species composition over 33 years in 17 temperate grasslands abandoned after agriculture at different points in time, collectively forming a chronosequence since abandonment from 1 to 80 years. We compare these abandoned sites with known agricultural land-use histories to never-disturbed sites as relative benchmarks. We specifically measured aspects of diversity at the local plot-scale (α-scale, 0.5 m2) and site-scale (γ-scale, 10 m2), as well as the within-site heterogeneity (β-diversity) and among-site variation in species composition (turnover and nestedness). At our α-scale, sites recovering after agricultural abandonment only had 70% of the plant species richness (and ~30% of the evenness), compared to never-ploughed sites. Within-site β-diversity recovered following agricultural abandonment to around 90% after 80 years. This effect, however, was not enough to lead to recovery at our γ-scale. Richness in recovering sites was ~65% of that in remnant never-ploughed sites. The presence of species characteristic of the never-disturbed sites increased in the recovering sites through time. Forb and legume cover declines in years since abandonment, relative to graminoid cover across sites. Synthesis. We found that, during the 80 years after agricultural abandonment, old fields did not recover to the level of biodiversity in remnant never-ploughed sites at any scale. β-diversity recovered more than α-scale or γ-scale. Plant species composition recovered, but not completely, over time, and some species groups increased their cover more than others. Patterns of ecological recovery in degraded ecosystems across space and long time-scales can inform targeted active restoration interventions and perhaps, lead to better outcomes

Spatially resolved acoustic spectroscopy for texture imaging in powder bed fusion nickel superalloys

© 2019 Author(s). There is a clear industrial pull to fabricate high value components using premium high temperature aerospace materials by additive manufacturing. Inconveniently, the same material properties which allow them to perform well in service render them difficult to process via powder bed fusion. Current build systems are charac-terised by high defect rates and erratic microstructure, leading to components with inferior mechanical properties. The work presents microstructural texture imaging of powder-bed fusion components by a non-contact laser ultrasonic method, Spatially Resolved Acoustic Spectroscopy (SRAS). In short, this work demonstrates the ability to SRAS to detect and characterise meso-scale crystalline texture features. Probing samples manufactured by powder bed fusion, in the common nickel based aerospace superalloy Inconel 718, it has been shown the the primary crystalline orientation of can be inferred from the measured velocity, with good agreement with Electron Backscatter Diffraction. The studied sample was found to have a microstructure formation that bore a heavy resemblance to the chosen scanning pattern, with clear influence from the geometry through varying scan vector length and island-boundary scan strategy. This work forms part of a progression towards deployment of a SRAS system as an in-situ inspection solution for PBF