Driving under the influence of risky peers : an experimental study of adolescent risk taking.

Both passive and active social influences may affect adolescents' dangerous driving. In this study, we used an experimental paradigm to delineate these two influences with actual peers. Adolescents completed a simulated driving task, and we measured risk preferences of each member of the peer group. We used hierarchical linear modeling to partition variance in risky decisions. Adolescents experienced many more crashes when they had “passengers” present who reported a strong preference for risk taking and who actively provided decision-making guidance. Although youth in the passive peer condition were also influenced by the riskiness of their peers, this relation was less strong relative to the active condition. We discuss the need for interventions focussing on active and passive peer influence

Top Legal Risks and Regulatory Trends Facing Canadian Optometrists

Doctors of Optometry are subject to many of the same legal risks and trends facing most regulated health professionals in Canada. These legal exposures range in scale from College investigations into an optometrist’s billing practices to seven-figure lawsuits alleging that an optometrist failed to appropriately diagnose andrefer a patient for further investigation and treatment. This article uses information gained through calls made by insured optometrists to the Canadian Association of Optometrist (CAO)’s Insurance Program pro bono legal services hotline along with over 15 years of program claims data to provide an overview of common legal risks and regulatory trends affecting the profession

Deep Learning Using Vision And LiDAR For Global Robot Localization

As the field of mobile robotics rapidly expands, precise understanding of a robot’s position and orientation becomes critical for autonomous navigation and efficient task performance. In this thesis, we present a snapshot-based global localization machine learning model for a mobile robot, the e-puck, in a simulated environment. Our model uses multimodal data to predict both position and orientation using the robot’s on-board cameras and LiDAR sensor. In an effort to minimize localization error, we explore different sensor configurations by varying the number of cameras and LiDAR layers used. Additionally, we investigate the performance benefits of different multimodal fusion strategies while leveraging the EfficientNet CNN architecture as our model’s foundation. Data collection and testing is conducted using Webots simulation software, and our results show that, when tested in a 12m x 12m simulated apartment environment, our model is able to achieve positional accuracy within 0.2m for each of the x and y coordinates and orientation accuracy within 2°, all without the need for sequential data history. Our results demonstrate the potential for accurate global localization of mobile robots in simulated environments without the need for existing maps or temporal data

Observational prospects for phase transitions at LISA : Fisher matrix analysis

A first order phase transition at the electroweak scale would lead to the production of gravitational waves that may be observable at upcoming space-based gravitational wave (GW) detectors such as LISA (Laser Interferometer Space Antenna). As the Standard Model has no phase transition, LISA can be used to search for new physics by searching for a stochastic gravitational wave background. In this work we investigate LISA's sensitivity to the thermodynamic parameters encoded in the stochastic background produced by a phase transition, using the sound shell model to characterise the gravitational wave power spectrum, and the Fisher matrix to estimate uncertainties. We explore a parameter space with transition strengths 0.01 < alpha < 0.5 and phase boundary speeds 0.4 < vw < 0.9, for transitions nucleating at T-n = 100 GeV, with mean bubble spacings 0.1 and 0.01 of the Hubble length, and sound speed c/root(3). We show that the power spectrum in the sound shell model can be well approximated by a four-parameter double broken power law, and find that the peak power and frequency can be measured to approximately 10% accuracy for signal-to-noise ratios (SNRs) above 20. Determinations of the underlying thermodynamic parameters are complicated by degeneracies, but in all cases the phase boundary speed will be the best constrained parameter. Turning to the principal components of the Fisher matrix, a signal-to-noise ratio above 20 produces a relative uncertainty less than 3% in the two highest-order principal components, indicating good prospects for combinations of parameters. The highest-order principal component is dominated by the wall speed. These estimates of parameter sensitivity provide a preliminary accuracy target for theoretical calculations of thermodynamic parameters.Peer reviewe

Observational prospects for gravitational waves from cosmological first order phase transitions at LISA

The era of gravitational wave (GW) observations began with the ground-breaking detection at the Laser interferometer GravitationalWave detector (LIGO), we are now exploring more of the GW power spectrum. Upcoming space-based detectors such as the Laser Interferometer Space Antenna (LISA) will probe, for the first time, the millihertz window of the GW spectrum with the hope of detecting astrophysical and cosmological sources. The source of interest in this thesis is a cosmological first order phase transition at the electroweak scale. Detecting these GWs from the early universe would provide the opportunity to delve further back in the history of the universe than ever before. In theories beyond the Standard Model a cosmological first order phase transition occurs when, below a critical temperature, bubbles of stable phase spontaneously nucleate in the surrounding metastable phase. These bubbles expand, collide, and merge until only the stable phase remains. This phenomenon produces a stochastic gravitational wave background (SGWB) that, once scaled due to the expansion of the universe, peaks in the frequency band corresponding to LISA. In the Standard Model this transition is a crossover and no GWs are produced. Thus, a detection of such a SGWB would be a discovery of new physics. In the following thesis, using the latest analytical model of a SGWB from a first order phase transition (the Sound Shell Model) and information from cutting edge simulations I explore LISA’s ability to perform parameter estimation on key phase transition parameters. I focus on two different parameterisations of the phase transition SGWB, the thermodynamic and spectral. The thermodynamic parameters are derived from the physics of the phase transition and consequently are related to the beyond standard model theory they inhabit. The spectral parameterisation is computationally cheaper than the thermodynamic parameterisation, which is advantageous when performing MCMC simulations. However, the connection from the spectral to thermodynamic parameters is an unanswered question. Here, we present a method for reconstructing the thermodynamic parameters from the spectral parameters. I use statistical methods including Fisher analysis and Markov chain Monte Carlo (MCMC) simulations to estimate parameter uncertainties on the two parameterisations. The impact of astrophysical foregrounds on resolving a SGWB for a first order phase transition are also investigated

Driving under the influence of risky peers: An experimental study of adolescent risk taking

Both passive and active social influences may affect adolescents' dangerous driving. In this study, we used an experimental paradigm to delineate these two influences with actual peers. Adolescents completed a simulated driving task, and we measured risk preferences of each member of the peer group. We used hierarchical linear modeling to partition variance in risky decisions. Adolescents experienced many more crashes when they had “passengers” present who reported a strong preference for risk taking and who actively provided decision-making guidance. Although youth in the passive peer condition were also influenced by the riskiness of their peers, this relation was less strong relative to the active condition. We discuss the need for interventions focussing on active and passive peer influence

Towards an understanding of the self-harming behaviours of vulnerable young people

Relatively little is known about the factors associated with young people’s engagement in self-harm. Given the existing vulnerabilities associated with being lookedafter, the first section of this thesis aimed to examine and synthesise the empirical literature investigating the psychosocial risk factors associated with self-harm and suicide among looked-after children (LAC). Systematic appraisal of fourteen studies highlighted several demographic, socio-environmental and psychological factors thought to place LAC at an increased risk of self-harm and suicidal behaviour. The findings have significant implications for intake assessment, treatment planning, service delivery, and staff training to address the complex emotional and behavioural needs of LAC. Given the potential risk that exposure to the self-harm of others might have on engagement in self-harm, the second section of this thesis aimed to explore, using Interpretative Phenomenological Analysis (IPA), how adolescents made sense of the selfharm of others, and how, if at all, the self-harm of others influenced their own behaviour and well-being. Eight young people, resident at one of two adolescent inpatient units, were interviewed and five themes emerged from the interview data: ‘Exposure to self-harm’, ‘An unpleasant environment’, ‘Helper vs helped’, ‘Separation from the attention seekers’, and ‘Competing for authenticity’. Self-harm prevention efforts aimed towards reducing the social transmission and stigma surrounding self-harm were discussed. The final section of the thesis adopts a critical and reflective stance to consider the decision-making processes regarding the thesis topic including the rationale for the study and the chosen methodology, and the practical and procedural challenges encountered during the course of the research, such as ethics approval processes and recruitment difficulties. The appraisal then goes onto review the researchers’ clinical reflections on the applications of the thesis findings, and the impact of the research on her journey through doctoral training

Examining tennis coaches constructions of their role in a perfromance setting: What is it like to coach an elite junior tennis player?

Despite a growing body of research into sports coaching there remains little understanding of what it is like to coach elite junior tennis players. The purpose of this PhD was to examine the lived coaching experience of independent tennis coaches and describe what it is like to be a coach of an elite junior tennis player. Using autoethnography to explore the first authors’ experiences of coaching elite juniors, and Interpretative Phenomenological Analysis (IPA) of 8 novice participants (1 – 4 years-experience) and 8 experienced participants (over 10 years-experience) this PhD sought to provide a comprehensive description of how tennis coaches described their experiences of tennis coaching. In total there were eight constructs identified in this PhD and they were; (a) connection, (b) competence, (c) competition, (d) conflict, (d) comprehension, (e) confidence, (f) code, and (g) coping. The eight constructs were classified under three types of coaching construct; contextual constructs (connection, conflict, & competition), efficacy constructs (competence, & confidence), and outcome constructs (comprehension, code, & coping). Acceptance of the challenges in coaching was a factor in experienced coaches describing different constructs compared to novice coaches. The findings of this research contribute to an evolving, problematic epistemology of sports coaching and highlight shortcomings in the capacity of tennis coach education to prepare novice coaches for their initiation into coaching. The findings present governing bodies opportunities to inform coach education literature and help tennis coaches to sustain themselves in an emotionally challenging role