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Solar radiation models have become essential tools for estimating incident solar energy reaching the earth's surface. Extensive evaluation of these models is a problem due to limited availability of measured solar radiation data. The performance of the SolarCalc model, which estimates hourly incoming solar radiation from limited daily meteorological data, was evaluated in the Northern Great Plains of Canada. The simulated hourly solar radiation was compared with observed hourly radiation from five meteorological stations operating through the growing season over a 4-yr period from 2003 to 2006. In addition, long-term year-round hourly solar radiation from one station over the period 1997 to 2007 was used to test the seasonal performance of the model. The model was also compared against the existing 1996-Liu and the FAO-56 models. The model simulated the year-round hourly solar radiation well (R2=0.85; d=0.96; E=0.82; MAE=50.84 W/m2; and RMSE= 96.92 W/m2). The model performance was also comparable to the existing models. However, the model over-predicted the hourly peak solar radiation during the summer and under-predicted during the winter. In addition, the model had none to a very small time-lag during all the seasons. Better model simulations were observed during the summer (R2=0.88, E=0.85) compared to the winter (R2=0.77, E=0.69). Improvements need to be done on simulation of peak radiation during winter and summer seasons. The SolarCalc model could be used as a potential tool for obtaining year-round hourly and daily solar radiation in areas with limited meteorological data. [ABSTRACT FROM AUTHOR]

Surface electrical and electromagnetic geophysical methods can map enhanced electrical conductivity caused by acid mine drainage in mine tailings piles. In this case study, we investigate quantitative relationships between geophysical responses and the electrical conductivity, acidity and salinity of tailing samples at the Central Manitoba Mine tailings in Manitoba, Canada. Previous electromagnetic surveys at the site identified zones of enhanced conductivity that were hypothesized to be caused by acid mine drainage. In the present study, high-resolution EM31 and DC-resistivity measurements were made on a profile through a zone of enhanced conductivity and laboratory measurements of salinity and pH were made on saturation paste extracts from an array of tailing samples collected from the upper 2 m of tailings along the profile. Observed spatial correlation of pH and pore-fluid salinity in the tailings samples confirms that the enhanced conductivity in the Central Manitoba Mine tailings is due to acid mine drainage. Contoured cross-sections of the data indicate that the acid mine drainage is concentrated near the base of the oxidized zone in the thicker parts of the tailings pile. The zone of increased acidity extends to the surface on sloping margins causing an increase in apparent conductivity in shallow penetrating geophysical responses. The quantitative relationship between measured pH and salinity shows that the conductivity increase associated with the acid mine drainage is due only in part to conduction by ions produced from dissociation of sulfuric acid. Comparison of the observations with fluid conductivity estimates based on statistical relationships of pH and ion concentrations in water samples from across the tailings pile shows that Ca 2 + and Mg 2 + ions also make significant contributions to the conductivity at all values of pH and Cu 2 + , Al 3 + and Fe 3 + ions make additional contributions at low pH. Variability in the measured conductivity at constant values of pH is explained by variations in the contribution of the SO 4 2 − to the measurements. The results of the study demonstrate the feasibility of using electromagnetic geophysical surveys to map acid mine drainage, and related ionic concentration, in mine tailings. [ABSTRACT FROM AUTHOR]

Introduction: The intersection of sexism with racism and xenophobia disproportionately exposes visible minority women to gender-based violence (GBV) at the community and systemic levels. This study aims to understand the knowledge strengths and gaps on GBV against visible minority women with an intersectional lens, revealing systemic barriers to accessing support and how these barriers intensify GBV and its effects. It will also identify effective and ineffective policies and practices in the literature to develop strategies addressing the root causes of GBV and supporting survivors., Methods and Analysis: We will conduct a mixed-methods systematic review using a convergent integrated approach to examine current literature on community- and systemic-level GBV against visible minority women. We will follow Joanna Briggs Institute's guidelines to converge data from both qualitative and quantitative studies to obtain an integrated qualitative synthesis on GBV in five countries: Canada, the USA, the UK, Australia and New Zealand. This analysis will be conducted following Thomas and Harden's thematic synthesis guidelines. Community members with lived experience of GBV will actively contribute to improving the relevance and interpretation of results, following a community-engaged research approach. Themes are expected to unveil various aspects of community- and systemic-level GBV due to the intersection of racism, xenophobia and sexism, alongside barriers in addressing GBV and research gaps., Ethics and Dissemination: Since this study does not involve primary data collection or the use of identifiable human data, no ethical approval will be needed. Results will be disseminated through integrated knowledge translation, involving collaboration with participants who have lived experience of GBV. The findings will be used to identify specific areas of policy intervention, including adopting culturally sensitive approaches, improving school and workplace policies and promoting rights of visible minority women., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The Association for Surgical Education established the Center for Excellence in Surgical Education Research and Training (CESERT) program in 1999 to support innovative research and education projects and programs that will advance surgical education. We sought to examine scholarly outcomes of the projects during the first 15 years of the program., Methods: E-mail surveys were sent to the 24 researchers who were awarded CESERT grants. Data collection focused on recipient professional experiences, publications, and presentations stemming from CESERT-funded research and impact on career development. For grant recipients who were unable to complete the survey, we obtained publication information on studies authored by the grant recipients that described the same grant-funded topic, described similar methods, and fell within the study timeline., Results: Complete survey data were obtained from 18 of the 24 grant recipients. Grants were most commonly awarded to General Surgeons (40%) and Education and Psychology PhDs (24%). Overall, 23 of the 25 projects had reached completion at the time of contact, and from these, 70 articles were published or in press. Abstract presentations were more common, with respondents documenting 84 projects locally, nationally, and internationally. Grant awards ranged from $8,122 to $97,000, with an average of $39,026. In total, the Association for Surgical Education Foundation distributed $988,000 in grant funding from 1999 to 2013. Respondents reported that CESERT funding was critical to their career as it legitimized their pursuit of educational research, helped them establish multidisciplinary and multi-institutional collaborations, provided greater visibility for their research, and helped them develop an understanding of educational principles and grant writing skills., Conclusions: Overall, the CESERT program has produced remarkable results. The careful review process and monitoring protocol have ensured that high-potential studies are funded and successful. These data support continued efforts to garner resources such that CESERT grants may be awarded to fund high-quality, high-impact projects., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Repeated-dose studies received by the New Substances Assessment and Control Bureau (NSACB) of Health Canada are used to provide hazard information toward risk calculation. These studies provide a point of departure (POD), traditionally the NOAEL or LOAEL, which is used to extrapolate the quantity of substance above which adverse effects can be expected in humans. This project explored the use of benchmark dose (BMD) modeling as an alternative to this approach for studies with few dose groups. Continuous data from oral repeated-dose studies for chemicals previously assessed by NSACB were reanalyzed using U.S. EPA benchmark dose software (BMDS) to determine the BMD and BMD 95% lower confidence limit (BMDL(05) ) for each endpoint critical to NOAEL or LOAEL determination for each chemical. Endpoint-specific benchmark dose-response levels , indicative of adversity, were consistently applied. An overall BMD and BMDL(05) were calculated for each chemical using the geometric mean. The POD obtained from benchmark analysis was then compared with the traditional toxicity thresholds originally used for risk assessment. The BMD and BMDL(05) generally were higher than the NOAEL, but lower than the LOAEL. BMDL(05) was generally constant at 57% of the BMD. Benchmark provided a clear advantage in health risk assessment when a LOAEL was the only POD identified, or when dose groups were widely distributed. Although the benchmark method cannot always be applied, in the selected studies with few dose groups it provided a more accurate estimate of the real no-adverse-effect level of a substance., (© 2011 Society for Risk Analysis.)