Approximate treatment of electron Coulomb distortion in quasielastic (e,e') reactions

In this paper we address the adequacy of various approximate methods of including Coulomb distortion effects in (e,e') reactions by comparing to an exact treatment using Dirac-Coulomb distorted waves. In particular, we examine approximate methods and analyses of (e,e') reactions developed by Traini et al. using a high energy approximation of the distorted waves and phase shifts due to Lenz and Rosenfelder. This approximation has been used in the separation of longitudinal and transverse structure functions in a number of (e,e') experiments including the newly published 208Pb(e,e') data from Saclay. We find that the assumptions used by Traini and others are not valid for typical (e,e') experiments on medium and heavy nuclei, and hence the extracted structure functions based on this formalism are not reliable. We describe an improved approximation which is also based on the high energy approximation of Lenz and Rosenfelder and the analyses of Knoll and compare our results to the Saclay data. At each step of our analyses we compare our approximate results to the exact distorted wave results and can therefore quantify the errors made by our approximations. We find that for light nuclei, we can get an excellent treatment of Coulomb distortion effects on (e,e') reactions just by using a good approximation to the distorted waves, but for medium and heavy nuclei simple additional ad hoc factors need to be included. We describe an explicit procedure for using our approximate analyses to extract so-called longitudinal and transverse structure functions from (e,e') reactions in the quasielastic region.Comment: 30 pages, 8 figures, 16 reference

The Fornax Spectroscopic Survey I. Survey Strategy and Preliminary Results on the Redshift Distribution of a Complete Sample of Stars and Galaxies

The Fornax Spectroscopic Survey will use the Two degree Field spectrograph (2dF) of the Anglo-Australian Telescope to obtain spectra for a complete sample of all 14000 objects with 16.5<=Bj<=19.7 in a 12 square degree area centred on the Fornax Cluster. By selecting all objects---both stars and galaxies---independent of morphology, we cover a much larger range of surface brightness and scale size than previous surveys. In this paper we present results from the first 2dF field. Redshift distributions and velocity structures are shown for all observed objects in the direction of Fornax, including Galactic stars, galaxies in and around the Fornax Cluster, and for the background galaxy population. The velocity data for the stars show the contributions from the different Galactic components, plus a small tail to high velocities. We find no galaxies in the foreground to the cluster in our 2dF field. The Fornax Cluster is clearly defined kinematically. The mean velocity from the 26 cluster members having reliable redshifts is 1560+/-80 km/s. They show a velocity dispersion of 380+/-50 km/s. Large-scale structure can be traced behind the cluster to a redshift beyond z=0.3. Background compact galaxies and low surface brightness galaxies are found to follow the general galaxy distribution.Comment: LaTeX format; uses aa.cls (included). Accepted for publication in Astronomy and Astrophysic

Relationship between trauma, psychological distress and help-seeking among corrective service workers

Background: Corrective service workers (CSWs) are at high risk of post-traumatic stress disorder (PTSD) and other mental health problems. Prevalence rates and help-seeking behaviours are under-researched within this population. Aims: To assess rates of PTSD and distress, and identify predictors of intention to seek help, among workers at an Australian corrective service agency. Methods: A cross-sectional online survey was used to collect data on staff demographics, employment, PTSD symptoms and current distress. Participants received a tailored feedback report including referral to relevant mental health services (where applicable) and were asked to indicate their likelihood of seeking help. Prevalence data are reported. Binary logistic regression was used to examine relationships between participant characteristics and help-seeking for those with probable PTSD and/or high psychological distress. Results: Participants (n=1001) were predominantly men (56.8%) with a mean age of 46.72 (SD=11.00). Over half (58.0%) were classified as probable PTSD cases, and one-third (33.0%) were experiencing high psychological distress. Around a third (34.3%) of participants with probable PTSD and/or elevated distress indicated they were likely to seek help. Older age and fewer years of service were associated with increased help-seeking intentions. Conclusions: CSWs were found to be experiencing probable PTSD at higher rates than reported in previous studies. Relatively few intended to seek help from mental health services, despite being provided with personalised screening and feedback along with access to specialised care. Future research should investigate the potential role of organisational support as a facilitator of help-seeking within this population

The importance of tectonic setting in assessing European Rare Earth potential

Rare earth element (REE) resources are commonly found associated with alkaline igneous complexes or carbonatites, or as secondary deposits derived from igneous rocks. Globally, many REE deposits occur around the margins of Archaean cratons, most in continental rift zones. Europe contains many such rift zones, which are generally younger in the south. Many of these rifts are intracontinental, whereas others are associated with the opening of oceans such as the Atlantic. All these rift systems have the potential to host REE resources, but whereas the older provinces of northern Europe are deeply exposed, exposures in southern Europe are largely at the supracrustal level. This paper considers how an understanding of the tectonic setting of Europe’s REE resources is vital to guide future exploration

Impact of mental health screening on promoting immediate online help-seeking: Randomized trial comparing normative versus humor-driven feedback

© Isabella Choi, David N Milne, Mark Deady, Rafael A Calvo, Samuel B Harvey, Nick Glozier. Background: Given the widespread availability of mental health screening apps, providing personalized feedback may encourage people at high risk to seek help to manage their symptoms. While apps typically provide personal score feedback only, feedback types that are user-friendly and increase personal relevance may encourage further help-seeking. Objective: The aim of this study was to compare the effects of providing normative and humor-driven feedback on immediate online help-seeking, defined as clicking on a link to an external resource, and to explore demographic predictors that encourage help-seeking. Methods: An online sample of 549 adults were recruited using social media advertisements. Participants downloaded a smartphone app known as “Mindgauge” which allowed them to screen their mental wellbeing by completing standardized measures on Symptoms (Kessler 6-item Scale), Wellbeing (World Health Organization [Five] Wellbeing Index), and Resilience (Brief Resilience Scale). Participants were randomized to receive normative feedback that compared their scores to a reference group or humor-driven feedback that presented their scores in a relaxed manner. Those who scored in the moderate or poor ranges in any measure were encouraged to seek help by clicking on a link to an external online resource. Results: A total of 318 participants scored poorly on one or more measures and were provided with an external link after being randomized to receive normative or humor-driven feedback. There was no significant difference of feedback type on clicking on the external link across all measures. A larger proportion of participants from the Wellbeing measure (170/274, 62.0%) clicked on the links than the Resilience (47/179, 26.3%) or Symptoms (26/75, 34.7%) measures (?2=60.35, P<.001). There were no significant demographic factors associated with help-seeking for the Resilience or Wellbeing measures. Participants with a previous episode of poor mental health were less likely than those without such history to click on the external link in the Symptoms measure (P=.003, odds ratio [OR] 0.83, 95% CI 0.02-0.44), and younger adults were less likely to click on the link compared to older adults across all measures (P=.005, OR 0.44, 95% CI 0.25-0.78). Conclusions: This pilot study found that there was no difference between normative and humor-driven feedback on promoting immediate clicks to an external resource, suggesting no impact on online help-seeking. Limitations included: lack of personal score control group, limited measures of predictors and potential confounders, and the fact that other forms of professional help-seeking were not assessed. Further investigation into other predictors and factors that impact on help-seeking is needed

‘The hardest job I’ve ever done’: a qualitative exploration of the factors affecting junior doctors’ mental health and well-being during medical training in Australia

Background: Medical practitioners can experience considerable stress and poor mental health during their careers, with doctors in training known to be particularly vulnerable. Previous research has documented work-related factors that may play a role in the mental health status of junior doctors. However, these and additional factors, need to be explored further by considering theory-driven, social, structural and contextual issues. This qualitative study aimed to explore the experiences of junior doctors working in Australian hospitals to identify factors that impact their mental health during medical training. Method: Semi-structured interviews were conducted with 12 junior medical officers (JMOs) employed across six hospitals in Australia. Transcribed de-identified interviews were analysed thematically using a data-driven inductive approach. Results: Four interrelated main themes were identified: i) professional hierarchies; ii) occupational stress; iii) emotional labour, and iv) taking distress home; which detail the complex affective, relational and professional experiences of JMOs. The accounts demonstrate how the social, professional and organisational dimensions of these experiences impact upon trainee’s well-being and mental health, both positively and negatively. Together, the findings document the dynamic, nuanced aspects of junior doctors’ experiences of medical training and practice and highlights the importance of relational connections and the workplace environment in shaping JMOs’ social and emotional well-being. Conclusion: The current study adds to the understanding of how junior doctors navigate medical training in Australian hospitals and highlights the complexities of this experience, particularly the ways in which mental health and well-being are shaped by different elements. These findings have important implications to inform new strategies to improve JMO mental health and to leverage work and non-work contexts to better support JMOs during medical training

eHealth interventions for the prevention of depression and anxiety in the general population: a systematic review and meta-analysis.

BACKGROUND: Anxiety and depression are associated with a range of adverse outcomes and represent a large global burden to individuals and health care systems. Prevention programs are an important way to avert a proportion of the burden associated with such conditions both at a clinical and subclinical level. eHealth interventions provide an opportunity to offer accessible, acceptable, easily disseminated globally low-cost interventions on a wide scale. However, the efficacy of these programs remains unclear. The aim of this study is to review and evaluate the effects of eHealth prevention interventions for anxiety and depression. METHOD: A systematic search was conducted on four relevant databases to identify randomized controlled trials of eHealth interventions aimed at the prevention of anxiety and depression in the general population published between 2000 and January 2016. The quality of studies was assessed and a meta-analysis was performed using pooled effect size estimates obtained from a random effects model. RESULTS: Ten trials were included in the systematic review and meta-analysis. All studies were of sufficient quality and utilized cognitive behavioural techniques. At post-treatment, the overall mean difference between the intervention and control groups was 0.25 (95% confidence internal: 0.09, 0.41; p = 0.003) for depression outcome studies and 0.31 (95% CI: 0.10, 0.52; p = 0.004) for anxiety outcome studies, indicating a small but positive effect of the eHealth interventions. The effect sizes for universal and indicated/selective interventions were similar (0.29 and 0.25 respectively). However, there was inadequate evidence to suggest that such interventions have an effect on long-term disorder incidence rates. CONCLUSIONS: Evidence suggests that eHealth prevention interventions for anxiety and depression are associated with small but positive effects on symptom reduction. However, there is inadequate evidence on the medium to long-term effect of such interventions, and importantly, on the reduction of incidence of disorders. Further work to explore the impact of eHealth psychological interventions on long-term incidence rates