Neural networks to retrieve in water constituents applied to radiative transfer models simulating coastal water conditions

Estimation of chlorophyll (Chl) using ocean colour remote sensing (OCRS) signals in coastal waters is difficult due to the presence of two other constituents altering the light signal: coloured dissolved organic matter (CDOM) and mineral suspended sediments (MSS). Artificial neural networks (NNs) have the capacity to deal with signal complexity and are a potential solution to the problem. Here NNs are developed to operate on two datasets replicating MODIS Aqua bands simulated using Hydrolight 5.2. Artificial noise is added to the simulated signal to improve realism. Both datasets use the same ranges of in water constituent concentrations, and differ by the type of logarithmic concentration distributions. The first uses a Gaussian distribution to simulate samples from natural water conditions. The second uses a flat distribution and is intended to allow exploration of the impact of undersampling extremes at both high and low concentrations in the Gaussian distribution. The impact of the concentration distribution structure is assessed and no benefits were found by switching to a flat distribution. The normal distribution performs better because it reduces the number of low concentration samples that are relatively difficult to resolve against varying concentrations of other constituents. In this simulated environment NNs have the capacity to estimate Chl with outstanding performance compared to real in situ algorithms, except for low values when other constituents dominate the light signal in coastal waters. CDOM and MSS can also be predicted with very high accuracies using NNs. It is found that simultaneous retrieval of all 3 constituents using multitask learning (MTL) does not provide any advantage over single parameter retrievals. Finally it is found that increasing the number of wavebands generally improves NN performance, though there appear to be diminishing returns beyond ~8 bands. It is also shown that a smaller number of carefully selected bands performs better than a uniformly distributed band set of the same size. These results provide useful insight into future performance for NNs using hyperspectral satellite sensors and highlight specific wavebands benefits

Training mental imagery skills of elite athletes in virtual reality

Mental imagery practice is widely used to help athletes prepare for competitions, as it can produce motor actions that enhance performance. The goal of imagery training for athletes is to create realistic images in their minds and to familiarize them with certain procedures, environments, and other aspects related to competition. Traditional imagery training methods use still images or videos, and athletes study the pictures or watch the videos in order to mentally rehearse. However, factors such as distractions and low realism can affect the training quality. In this paper, we present a Virtual Reality (VR) solution and a study that explores our hypotheses that H1: high-fidelity VR systems improve mental imagery skills, that H2: the presence of elements such as virtual onlookers or photographers in the VR environment arouse stronger emotional reactions and affect, and that H3: the presence of elements such as onlookers or photographers in the VR environment results in better mental imagery skill improvement. For that purpose, seven elite snow sports athletes were exposed to three training methods, Video, VR-Empty, and VR-Crowded. Our results show that a VR simulation with virtual onlookers (VR-Crowded) can significantly increase heart rate, which can induce increased emotional arousal. The results from validated questionnaires show no significant difference for the three training methods in terms of mental imagery and affect, but the results show an ascending trend for the athlete’s arousal from Video to the VR-Crowded condition. Gaze detection heat maps of interest areas for the two VR conditions support hypothesis H2 that environmental factors such as the presence of photographers, staff, and onlookers can increase head and eye movement, possibly indicating an increase in emotional arousal during imagery training. According to verbal feedback and interviews, athletes are more likely to use innovative training methods (e.g., the high-fidelity VR method) than traditional video-training methods

Informing investment to reduce inequalities: a modelling approach

Background: Reducing health inequalities is an important policy objective but there is limited quantitative information about the impact of specific interventions. Objectives: To provide estimates of the impact of a range of interventions on health and health inequalities. Materials and methods: Literature reviews were conducted to identify the best evidence linking interventions to mortality and hospital admissions. We examined interventions across the determinants of health: a ‘living wage’; changes to benefits, taxation and employment; active travel; tobacco taxation; smoking cessation, alcohol brief interventions, and weight management services. A model was developed to estimate mortality and years of life lost (YLL) in intervention and comparison populations over a 20-year time period following interventions delivered only in the first year. We estimated changes in inequalities using the relative index of inequality (RII). Results: Introduction of a ‘living wage’ generated the largest beneficial health impact, with modest reductions in health inequalities. Benefits increases had modest positive impacts on health and health inequalities. Income tax increases had negative impacts on population health but reduced inequalities, while council tax increases worsened both health and health inequalities. Active travel increases had minimally positive effects on population health but widened health inequalities. Increases in employment reduced inequalities only when targeted to the most deprived groups. Tobacco taxation had modestly positive impacts on health but little impact on health inequalities. Alcohol brief interventions had modestly positive impacts on health and health inequalities only when strongly socially targeted, while smoking cessation and weight-reduction programmes had minimal impacts on health and health inequalities even when socially targeted. Conclusions: Interventions have markedly different effects on mortality, hospitalisations and inequalities. The most effective (and likely cost-effective) interventions for reducing inequalities were regulatory and tax options. Interventions focused on individual agency were much less likely to impact on inequalities, even when targeted at the most deprived communities

Living through continuous displacement : resisting homeless identities and remaking precarious lives

This article considers how individuals who experience continuous displacement from housing manage the ‘spoiled identity’ of homelessness. The research draws on in-depth, biographical interviews with 39 individuals living in Oxford, a high-cost UK city. All had experienced forms of homelessness in the previous three years. Building on critical debates around experiences of precarity in urban geography, the article explores how individuals construct and maintain a sense of identity whilst living precarious lives. Participants were constantly confronted with their own precarity in pressured housing markets, which fostered their displacement, and then undermined re-entry into stable housing. Yet, participants described their attempts to maintain a ‘normal’ life, rejecting homeless subjectivities as they anchored their identity to daily practices of self care. These were also a key means of distinction from others experiencing displacement, enabling individuals to dis-identify from those characterised by moral and personal failings, thus highlighting their own responsibility and resourcefulness. Others described the bodily transformation that was associated with assuming the identity of ‘homeless’. Participants moved between different subject positions, with distinct narratives through which individuals sought to reclaim precarious identities, foregrounding alternative choices, pride in survival and resourcefulness, and freedom. Whilst this occurred within a context of extreme constraint, individuals were actively engaged in attempts to construct a sense of worth and value that was denied by a ‘homeless identity’. The article contributes to contemporary debates foregrounding social processes in understandings of the lived experiences of marginalisation, as well as adding empirical depth to representations of hidden homelessness

‘Teachers matter’: the impact of mandatory reporting on teacher education in Ireland

The role of teachers in safeguarding the welfare of children is long acknowledged. However, recent research in Ireland found that the training provided to teachers on child protection issues was lacking (Buckley and McGarry, 2011). The frequent interactions teachers have with children and their expertise in terms of typical child development place them in an ideal position for identifying possible signs of abuse. Yet despite this advantage, research indicates that schools fail to report a substantial proportion of suspected child abuse cases (Kenny, 2004). The oft cited reasons for this may be conceptualised as; explicit reasons such as, a lack of knowledge about child abuse issues; and implicit reasons such as, the individual teachers’ belief system about abuse. The current paper discusses implicit as well as explicit obstacles to teachers’ ‘engagement’ with, and consequent barriers to their responding to, child protection issues. The current changes in initial teacher education and the introduction of mandatory reporting for professionals in Ireland, is an opportune time to raise this issue and the need for holistic education in child protection for teachers

How could differences in 'control over destiny' lead to socio-economic inequalities in health? : A synthesis of theories and pathways in the living environment

We conducted the first synthesis of theories on causal associations and pathways connecting degree of control in the living environment to socio-economic inequalities in health-related outcomes. We identified the main theories about how differences in 'control over destiny' could lead to socio-economic inequalities in health, and conceptualised these at three distinct explanatory levels: micro/personal; meso/community; and macro/societal. These levels are interrelated but have rarely been considered together in the disparate literatures in which they are located. This synthesis of theories provides new conceptual frameworks to contribute to the design and conduct of theory-led evaluations of actions to tackle inequalities in health

Food Fury: Online Casual Game Development for Nutrition Education

Introduction: The United States is currently experiencing increased prevalence of obesity. This is a particular problem amongst children who require dietary and activity behavioral change to mitigate this problem. The use of computer games as channels to motivate health behavior in children is increasing. Casual games are a subset of computer games that are simple in design, easy to access and play, popular with children, and have the potential to be effective for drill and practice learning. [See PDF for complete abstract