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This paper reviews the factors and criteria for the design of new and the retrofitting of existing dry detention ponds to enhance removal of total suspended solids (TSS) from stormwater. Detention time is discussed as the most important factor affecting TSS removal. Two-stage facilities and multi-level outlet design are important means of enhancing TSS removal in dry ponds. Two dry ponds within the city of Edmonton were selected to evaluate their TSS removal. The level of expected TSS removal is low owing to the relatively short detention times for both ponds. Methods for retrofitting the dry ponds to enhance TSS removal are discussed.Key words: dry pond, stormwater, TSS removal, detention time, retrofitting.Cet article passe en revue les facteurs et critères de conception de nouveaux étangs de rétention, et de modification de ceux déjà existants, avec pour but d'améliorer la capacité d'enlèvement des substances solides totales en suspension (SST) contenues dans les eaux de ruissellement. Le temps de rétention est examiné en tant que facteur principal affectant l'enlèvement des SST. Les installations à deux étages et la conception de sorties multi-niveaux sont des procédés importants qui améliorent l'enlèvement des SST dans les étangs. Deux étangs de la Ville d'Edmonton ont été sélectionnés et leur capacité de rétention a été évaluée. Le niveau d'enlèvement des SST escompté est bas compte-tenu des temps de rétention relativement courts de ces deux étangs. Les méthodes de modification des étangs visant à améliorer l'enlèvement des SST sont examinées.Mots clés : étang, eaux de ruissellement, enlèvement des SST, temps de rétention, réajustement.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Objectives: We assessed the prevalence and correlates of sexual concerns and associated distress among women living with HIV in Canada., Methods: We analyzed cross-sectional survey data from the Canadian HIV Women's Sexual and Reproductive Health Cohort Study (2017-2018). Self-identified women living with HIV were asked about sexual concerns post-HIV diagnosis and associated distress (none, mild, moderate, severe). Five areas of concern were assessed, including difficulties related to sexual self-esteem, sexual function, relationships, and emotional and behavioral aspects of sex. Logistic regression analyses identified correlates of reporting any sexual concerns and severe distress about these concerns., Results: Of 906 participants (median age 48, Q1-Q3 = 41-55), 596 (65.8%) reported sexual concerns post-HIV diagnosis. We found a high prevalence of concerns related to relationships (43.3%), sexual self-esteem (49.4%), and emotional aspects of sex (45.4%), relative to sexual functioning (38.4%) and behavioral aspects (33.7%). Of those with sexual concerns, 36.7% reported severe distress. Reports of severe distress were the highest for relationship difficulties (32.5%), relative to other areas of concern (21.4%-22.8%). In adjusted analyses, women reporting sexual dissatisfaction and high HIV-related stigma had significantly higher odds of reporting sexual concerns. Conversely, those reporting higher resilience, better mental health, African, Caribbean, and Black identity, and sex as somewhat unimportant, not at all important, or neutral to their lives had lower adjusted odds. Factors associated with severe distress about sexual concerns included older age, body dissatisfaction, sexual dissatisfaction, and high HIV-related stigma, while better mental health and getting support from someone living with HIV were protective. While 84.4% of women had discussed with a provider how viral load impacts transmission risk, only 40.6% had conversations about sexual wellbeing., Conclusion: More attention to women's sexual wellbeing within social and relational contexts is critical to ensure the sexual rights of women living with HIV are upheld.

Wildfires can have severe and lasting impacts on the water quality of aquatic ecosystems. However, our understanding of these impacts is founded primarily from studies of small watersheds with well-connected runoff regimes. Despite the predominance of large, low-relief rivers across the fire-prone Boreal forest, it is unclear to what extent and duration wildfire-related material (e.g., ash) can be observed within these systems that typically buffer upstream disturbance signals. Following the devastating 2016 Fort McMurray wildfire in western Canada, we initiated a multi-faceted water quality monitoring program that suggested brief (hours to days) wildfire signatures could be detected in several large river systems, particularly following rainfall events greater than 10 mm. Continuous monitoring of flow and water quality showed distinct, precipitation-associated signatures of ash transport in rivers draining expansive (800-100,000 km 2 ) and partially-burned (<1-22 percent burned) watersheds, which were not evident in nearby unburned regions. Yields of suspended sediment, nutrients (nitrogen, phosphorus) and metals (lead, others) from impacted rivers were 1.2-10 times greater than from those draining unburned regions. Post-fire suspended sediment concentrations in impacted rivers were often larger than pre-fire 95% prediction intervals based on several years of water sampling. These multiple lines of evidence indicate that low-relief landscapes can mobilize wildfire-related material to rivers similarly, though less-intensively and over shorter durations, than headwater regions. We propose that uneven mixing of heavily-impacted tributaries with high-order rivers may partially explain detection of wildfire signals in these large systems that may impact downstream water users., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)