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Wood as a building material is a common roofing material in both contemporary homes and older properties such as heritage buildings. As a combustible material, wood can be associated with higher rates of building damage from wildfires. This study investigates the spontaneous ignition of contemporary Eastern white cedar shingles (Thuja occidentalis), a commonly used roofing product in older houses and heritage properties in Ontario. The samples were tested with a cone calorimeter under radiant heat without a spark igniter. The samples were conditioned under three moisture content categories: (1) ambient; (2) dry; and (3) wet. They were tested using incident radiative heat for 15 min or until 2 min after flameout under three heat fluxes: (1) 20 kW/m2, (2) 30 kW/m2, and (3) 40 kW/m2. Moisture content and heat flux had a clear impact on ignition and pyrolysis. All samples ignited at 40 kW/m2 and the dry samples ignited at 30 kW/m2. In samples which did not ignite, indicators of pyrolysis such as off-gassing, charring, and ember formation were delayed as the moisture content increased. However, dry samples at 40 kW/m2 had a slower average ignition time by 20 s and a lower average peak HRR than the ambient samples by 8 kW/m2. It was posited that it could be due to the char layer forming faster at the lower moisture content, creating a protective layer that delayed ignition. Future research will investigate the impact of incident heat flux and moisture content on piloted ignition of cedar shingles via firebrands, which is common during wildfires. Research to evaluate the performance and ignition of heritage cedar shingles versus contemporary cedar shingles is also recommended. [ABSTRACT FROM AUTHOR]

The demand for evidence syntheses to inform urgent decision-making surged during the pandemic. The challenging circumstances of the pandemic created significant hurdles for both those requesting and creating evidence syntheses, leading to the refinement and adjustment of evidence synthesis practices. This research sought to capture and explore how the field of evidence synthesis evolved and adapted during the pandemic from the perspective of those who produced evidence syntheses in Canada. In this qualitative study, semi-structured interviews were carried out between October 2022 to January 2023. Twenty-two participants from 19 different organizations across seven provinces and one territory were interviewed. This included producers of evidence syntheses from academic institutions, not-for-profit organizations, and provincial and federal government. Data analysis was conducted thematically using a phenomenological approach. Results indicated the evidence synthesis landscape drastically changed during the pandemic including short timelines to produce syntheses and changes in the volume, types, and quality of literature included in them. Due to the changing landscape and different needs of requestors, evidence synthesis methodologies evolved, synthesis products were tailored, and quality assessment tools were adapted. In addition, the use of artificial intelligence, processes for engaging subject matter experts and patient-citizen partners, and the coordination of the evidence synthesis community changed. The findings of this study contribute to the ongoing dialogue surrounding evidence synthesis to inform decision-making, and highlights the importance of flexibility and necessity of continuously evolving methodologies to meet the demands of frequently changing landscapes. The lessons learned from this study can help inform future strategies for improving evidence synthesis practices not only in the face of public health emergencies, but also in everyday practice. [ABSTRACT FROM AUTHOR]

Research supports recess, however, playground injuries are prevalent with more than 200,000 cases per year requiring medical attention. School playgrounds are among the leading location for injury. The purpose was to identify the safety and risk factors of playground environments and impact attenuation characteristics of surfacing materials. Results demonstrated 46% playground spaces protected students from traffic. Results found 75% of playgrounds were exposed to full sun, and unitary surface materials were up to 49°F warmer than the air temperature. There was an increase in the probability of risk whether equipment height was over 9 ft for loose fill surfacing materials or over 6 ft for unitary surfaces. Loose strings or ropes looped over equipment were found on 23% of playgrounds. This study provides discussion and data pertaining to numerous aspects of playground safety. Strategies for school nurses are shared to shape policies and education for playground safety practices.

Wildfire impacts are increasing due to the multiplicative effect of several factors, including climate change, increased vulnerability in the wildland-urban interface, and impacts of management decisions. This has also led to an increase in evacuations due to the number of wildfires and people affected. This study collected information on behaviour during wildfire evacuation to fill critical research gaps in human behaviour and evacuation knowledge. Seven videos of residents' evacuations from the 2016 Fort McMurray fire were collected from public platforms. Their routes were analyzed, and notable behavioural events were recorded. The evacuees mainly used major roads before getting onto the highway (the only route available for vehicular egress). The notable behaviours observed included using opposite lanes and driving outside of marked roads to avoid congestion. Much of the observed behaviours appeared to be motivated by the surrounding traffic or fire behaviour, further supporting the need for further studies of evacuation. [ABSTRACT FROM AUTHOR]

This study investigates the effect of the particle size and solid-to-liquid ratio on the dissolution rate of magnesium (Mg) and silicon (Si) in heat-activated lizardite. The investigation was conducted under specific conditions: without the presence of sodium bicarbonate (NaHCO3), at a moderate temperature (40 °C), and under elevated CO2 pressure (100 bar). The aim was to isolate the dissolution reactions and enhance comprehension of the factors constraining the overall yields in the Albany Research Center (ARC) mineral carbonation process. Our study disclosed two distinct dissolution regimes: an initial stage with a rapid initial rate of Mg extraction, resulting in the fraction of Mg extracted ranging from 30 to 65% during the first 20 min of the experiment, following which the dissolution rate decreases dramatically. The initial rapid dissolution stage is primarily driven by the low pH of the supernatant solution, resulting from CO2 dissolution, leading to a higher concentration of protons that extract Mg2+ cations. However, as the heat-activated lizardite dissolution progresses, the pH increases due to the high level of leached Mg2+, and a diffusion barrier forms due to the precipitation of amorphous silica. This phenomenon ultimately slows down the mineral's dissolution rate during the latter stages of particle dissolution. [ABSTRACT FROM AUTHOR]

Scientific institutions are increasingly embracing values of inclusivity and public engagement, but how do these two dimensions intersect? Science festivals have rapidly expanded in recent years as an outgrowth of these values, aiming to engage and educate the public about scientific topics and research. While resources invested in public engagement by scientists, universities, and governments are admirable in principle; this study indicates that their ambition to broaden the reach of science may be going unrealized in practice. Using data from three major UK science festivals, we demonstrate such events are disproportionately reaching economically privileged and educated audiences already invested in science, as opposed to diverse and broadly representative samples of the general public. Our results demonstrate that these science festivals are falling short of their aims to make science accessible to a broad audience. There is a clear need for improved practices and on-going evaluation to ensure science festivals include those who are not already scientifically converted.