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Mobile air pollution measurements have the potential to provide a wide range of insights into emission sources and air pollution exposure. The analysis of mobile data is, however, highly challenging. In this work we develop a new regression-based framework for the analysis of mobile data with the aim of improving the potential to draw inferences from such measurements. A quantile regression approach is adopted to provide new insight into the distribution of NOx and CO emissions in Central and Outer London. We quantify the emissions intensity of NOx and CO (ΔNOx/ΔCO2 and ΔCO/ΔCO2) at different quantile levels (τ) to demonstrate how transient high-emission events can be examined in parallel to the average emission characteristics. We observed a clear difference in the emissions behaviour between both locations. On average, the median (τ = 0.5) ΔNOx/ΔCO2 in Central London was 2x higher than Outer London, despite the stringent emission standards imposed throughout the Ultra Low Emissions Zone. A comprehensive vehicle emission remote sensing data set (n ≈ 700,000) is used to put the results into context, providing evidence of vehicle behaviour which is indicative of poorly controlled emissions, equivalent to high-emitting classes of older vehicles. Our analysis suggests the coupling of a diesel-dominated fleet with persistently congested conditions, under which the operation of emissions after-treatment technology is non-optimal, leads to increased NOx emissions.

This work investigates temperature’s effect on the critical energy release rate using damage mechanics material models and the element deletion method. The energy release rate describes the decrease in total potential energy per increase in crack surface area. The critical energy release rate is widely used as the failure criterion for various elastic and plastic materials. In real-life scenarios, fractures may occur at different temperatures. The temperature dependency of the critical energy release rate for aluminum 2024-T351 and titanium Ti-6Al-4V is studied in this work. We utilized test-data-based advanced material models of these two alloys, considering the strain rate, temperature, and state of stress for plasticity and failure. These material models are used to simulate a three-dimensional fracture specimen to find the critical energy release rate at different temperatures. A new method to calculate the critical energy release rate with the element deletion method is introduced and verified with the virtual crack opening method. This method enables the calculation of the energy release rate in a classical damage mechanics simulation for dynamic cack propagation. The simulation result indicates that the critical energy release rate increases with rising temperatures for these alloys.

Parents of autistic children have historically reported hardships related to raising their children. However, the access to resources related to the childrearing of an autistic child is not equitable, therefore resulting in exacerbated difficulties for parents in low-resource settings. In these situations, peer support may be a protective factor for parental resilience in which they receive various supports from other parents of an autistic child with similar experiences. Despite its potential utility, little is known about such parent-to-parent support as evidenced by no synthesis of relevant literature. To address this gap, we present a scoping review of 25 studies that included parent-to-parent support among parents of autistic children. Across these studies, a total of 141 and 747 parents participated as parent mentors and mentees with some heterogeneity in their demographic characteristics. We also identified how parent mentors were trained to provide support to their peers and social validity data related to parent-to-parent support and provided implications for future intervention research.

Although global prevalence of autism has grown substantially, researchers still report inequity in access to evidence-based interventions in many low-resource settings where majority of world's children live. Capacity building of diverse stakeholders in low-resource settings has been suggested to be a potential way to mitigate low levels of access to resources; however, little is known about what these stakeholders consider as helpful strategies in capacity building. In this qualitative research, we conducted five focus groups with 30 Mongolian caregivers of children with autism and 15 individual interviews with professionals in Mongolia. Three themes emerged from this study, including (a) partnership, (b) advocacy, and (c) empowerment. Each theme also contained several categories. For example, partnerships included enhancing collaboration among stakeholders and collaboration with international development agencies; advocacy included parental and legislative advocacy; and empowerment included training for diverse stakeholders, including caregivers and professionals. Implications and directions for future research are also suggested.