Consent and brain trauma in schools

In a recently published edition of the Journal of Physical Education, Recreation and Dance, we read with interest responses given by readers on ‘how should coaches, parents and participants be informed of the risks and rewards of their participation’ (2017: 54) in sports with a risk of head trauma. Over the past decade, increasing attention has been forthcoming on the issues of traumatic brain injuries, repetitive sub-concussive traumas and the long-term, and sometimes fatal, implications of concussion (McKee et al. 2014) often focusing on contact sports, such as American Football, Ice Hockey or the various codes of Rugby

Primordial Non-Gaussianity: Baryon Bias and Gravitational Collapse of Cosmic String Wakes

I compute the 3-D non-linear evolution of gas and dark matter fluids in the neighbourhood of cosmic string wakes which are formed at high redshift ($z\simeq 2240$) for a ``realistic'' scenario of wake formation. These wakes are the ones which stand out most prominently as cosmological sheets and are expected to play a dominant r\^ole in the cosmic string model of structure formation. Employing a high-resolution 3-D hydrodynamics code to evolve these wakes until the present day yields results for the baryon bias generated in the inner wake region. I find that today, wakes would be $1.5 h^{-1}$ Mpc thick and contain a 70% excess in the density of baryons over the dark matter density in their centre. However, high density peaks in the wake region do not inherit a baryon enhancement. I propose a mechanism for this erasure of the baryon excess in spherically collapsed objects based on the geometry change around the collapsing region. Further, I present heuristic arguments for the consequences of this work for large scale structure in the cosmic string model and conclude that the peculiarities of wake formation are unlikely to have significant import on the discrepancy between power spectrum predictions and observations in this model. If one invokes the nucleosynthesis bound on $\Omega_b$ this could be seen as strengthening the case against $\Omega_m=1$ or for low Hubble constants.Comment: 21 pages, 7 figures, 2 tables, prepared with the AASTeX package. Minor modifications, results unchanged. ApJ in press, scheduled for Vol. 50

The Power Spectrum of the PSC Redshift Survey

We measure the redshift-space power spectrum P(k) for the recently completed IRAS Point Source Catalogue (PSC) redshift survey, which contains 14500 galaxies over 84% of the sky with 60 micron flux >= 0.6 Jansky. Comparison with simulations shows that our estimated errors on P(k) are realistic, and that systematic errors due to the finite survey volume are small for wavenumbers k >~ 0.03 h Mpc^-1. At large scales our power spectrum is intermediate between those of the earlier QDOT and 1.2 Jansky surveys, but with considerably smaller error bars; it falls slightly more steeply to smaller scales. We have fitted families of CDM-like models using the Peacock-Dodds formula for non-linear evolution; the results are somewhat sensitive to the assumed small-scale velocity dispersion \sigma_V. Assuming a realistic \sigma_V \approx 300 km/s yields a shape parameter \Gamma ~ 0.25 and normalisation b \sigma_8 ~ 0.75; if \sigma_V is as high as 600 km/s then \Gamma = 0.5 is only marginally excluded. There is little evidence for any `preferred scale' in the power spectrum or non-Gaussian behaviour in the distribution of large-scale power.Comment: Latex, uses mn.sty, 14 pages including 11 Postscript figures. Accepted by MNRA

Urban water demand forecasting and demand management: Research needs review and recommendations

Urban Water Demand Forecasting and Demand Management - Research Needs Review and Recommendations This study undertook a preliminary investigation of current research into urban water demand. The objective was to conduct a preliminary review of this field, to provide the beginnings of a comprehensive database of industry knowledge in this area and to identify research gaps. It is anticipated that this will lead to a more considered approach to research funding by the Australian water industry and maximise the potential for transparency and collaboratio

Molecular line CO (2→1) observations of ultraluminous IRAS galaxies

CO (J=2→1) observations of six ultraluminous IRAS galaxies are presented. Four of these galaxies have no previous CO J=2→1 data and two have no previous CO detections at all. Based on these observations, molecular hydrogen masses are estimated and range from 5x109 to 1.8x1010 M⊙. The present data follow the well established correlation that exists between the infrared luminosity LIR and the molecular mass content. The high values of the LIR/MH2 suggest either an increased star formation efficiency and / or an additional source of luminosity such as an active nucleus. The ratio R=(J=2→1)/(J=1→0) between the J=2→1 and 1→0 line temperatures, is examined next using our J=2→1 intensities and other published CO J=1→0 data. For Arp 220, Mrk 231, Mrk 273 R lies in the range 0.7 to 1.1; for IRAS 05189 the CO intensity and the ratio R were both found to have extremely low values. The low values of R≤1 found for all galaxies, suggest that the line profiles are dominated by emission coming from optically thick thermalized CO. Finally the line profiles are examined and compared to published models concerning the distribution and kinematics of the gas. Assuming that the CO is distributed in a disk as in normal spiral galaxies, then this region is probably concentrated towards the center of the galaxies

Promoting Mental Health and Wellbeing with Men and Boys: What Works?

In May 2014 the Movember Foundation commissioned the Centre for Men’s Health, Leeds Beckett University, in collaboration with the Men’s Health Forum (England & Wales), to gather the current research evidence and practical (‘tacit’) knowledge about the core elements that make for successful work with boys and men around mental health promotion, early intervention and stigma reduction

Successful mental health promotion with men: evidence from 'tacit knowledge'

There remains significant concern about men’s mental health, particularly in terms of personal and societal barriers to help-seeking, negative coping mechanisms and high suicide rates. This paper presents findings from a multi-phase study looking at ‘what works’ in mental health promotion for men. Work here reports the collection and analysis of the tacit knowledge of those working within mental health promotion interventions for men. A ‘multiple hub and spoke’ approach was used to assist data collection. Thirteen key players, active in the men’s mental health field, half from the UK and half beyond, formed an Investigative Network collecting data, mainly through interviews, from wider geographical and professional community contexts where they had networks. The focus of data collection was on ‘what works’ in mental health promotion for men. Data was analysed using thematic analysis techniques. Findings suggest that settings which created safe male spaces acted to promote trust, reduce stigma and normalise men’s engagement in interventions. Embedding interventions within the communities of men being engaged, fully involving these men, and holding ‘male-positive’ values engendered familiarity and consolidated trust. Using ‘male-sensitive’ language and activity-based approaches allowed for positive expressions of emotions, facilitated social engagement, and provided a base for open communication. Appropriate partnerships were also seen as a necessary requirement for success and as crucial for maximising intervention impact. The importance of gender and ‘masculinity’ was apparent throughout these findings and taking time to understand gender could facilitate positive ways of working alongside men, increasing levels of engagement and successful outcomes

The cluster abundance in cosmic string models for structure formation

We use the present observed number density of large X-ray clusters to constrain the amplitude of matter density perturbations induced by cosmic strings on the scale of $8 h^{-1}$Mpc ($\sigma_8$), in both open cosmologies and flat models with a non-zero cosmological constant. We find a slightly lower value of $\sigma_8$ than that obtained in the context of primordial Gaussian fluctuations generated during inflation. This lower normalization of $\sigma_8$ results from the mild non-Gaussianity on cluster scales, where the one point probability distribution function is well approximated by a $\chi^2$ distribution. We use our estimate of $\sigma_8$ to constrain the string linear energy density $\mu$ and show that it is consistent with the COBE normalization.Comment: 5 pages, 2 figure

Preliminary progress in establishing motion fidelity requirements for maritime rotorcraft flight simulators

Copyright © 2018 by AHS International, Inc. All rights reserved. The research presented in this paper is part of a project underway at the University of Liverpool (UoL) which aims to develop overall simulation fidelity requirements for maritime rotorcraft flight simulators. This requires a structured examination of individual Modelling and Simulation (M&S) elements, such as motion and visual cues, flight dynamics model and ship airwake integration. The paper reports the initial results of motion cueing research that has been conducted to assess and optimise the motion drive laws and determine high fidelity motion cueing for simulated shipboard operations. To do this, an objective technique, Vestibular Motion Perception Error (VMPE), has been developed. The technique was utilised to optimise the motion cues in UoL's Heliflight-R simulator for a simulated helicopter landing on an aircraft carrier in a turbulent environment. Four motion tuning sets were derived offline and experimentally tested. Results show the influence of different motion cues and airwake conditions on the pilot's overall self-motion perception, control strategy and task performance. It was found that high-fidelity motion cueing becomes more desirable for the pilot at higher airwake wind conditions, for which an 'Optimised' motion setting was obtained using the new technique, than at lower airwake turbulence conditions