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• Canadian E-waste recycling data from 2012 to 2020 are systematically assessed. • Regression and Mann-Kendall analyses are used to quantify the temporal trends. • Both collection points and stewardship organizations have grown exponentially. • The role of public awareness on e-waste recycling varied between provinces. • Operational expenditure and revenue on stewardship resilience should be monitored. Electronic waste recycling companies have proliferated in many countries due to valuable materials present in end-of-life electronic and electrical equipment. This article examined the business characteristics and management performance of Electronic Products Recycling Association (EPRA), a Canadian nationwide electronic product stewardship organization. The organization's annual performance reports, from 2012 to 2020, for nine Canadian provinces in which it currently operates were aggregated and analyzed. Temporal analysis using regression and Mann-Kendall tests were employed, and five characteristics of EPRA's business were analyzed, including e-waste products collected, number of drop-off locations, efforts to build public awareness, operating expenses, and growth of e-waste stewardship. Results show a decline in the amount of e-waste collected across the provinces, except in New Brunswick, which started its program in 2017. The Mann-Kendall test revealed declining temporal trends in most provinces. Although the collection/drop off sites and stewardship organizations increased astronomically over the study period in Canada, the amounts of e-waste collected decreased. We found that public awareness generally did not increase the amount of e-waste collected, and these campaigns only appeared to be effective in jurisdictions with good accessibility of e-waste recycling. Processing cost accounted for the majority of the e-waste management budget in Canada, and different factors affected the financial success of the stewards differently. [ABSTRACT FROM AUTHOR]

Streptococcus pneumoniae serotype 19A is a highly diverse, often antimicrobial-resistant Gram-positive bacterium which can cause invasive pneumococcal disease (IPD). In 2021, public health authorities in the Canadian province of Québec observed an increase of serotype 19A IPD in children <5 years. The purpose of this study was to determine the clonal composition of serotype 19A isolates collected from this age group in Québec, from 2016 to 2021. Forty-one and 37 IPD isolates from children <5 years from Québec and the remainder of Canada, respectively, were sequenced using the Illumina NextSeq platform. Phylogenetic analysis using SNVPhyl identified three clusters, corresponding to three common clones of serotype 19A: CC199, CC320 and ST695. CC199, predominantly represented by ST416, accounted for similar proportions of serotype 19A isolates collected from children in Québec (19.5 %) and other Canadian jurisdictions (OCJs, 21.6 %), with significant presence of ermB (62.5 % and 60 % of ST416 isolates, respectively). CC320 was more commonly identified from OCJs in comparison to Québec (18.9 % vs. 7.3 %, respectively), but were highly antimicrobial-resistant regardless of region. ST695 was the most common clone of serotype 19A collected in Québec from children <5 years, representing 65.9 % of isolates collected over the study period (40.5 % of isolates collected in OCJs). Phylogenetic analysis identified geographical differences in ST695 across Canada; including a large clade specific to Québec (with both susceptible and macrolide-resistant [ ermB ] subclades), and a separate macrolide-resistant (mefA) clade associated with OCJs. The Québec-specific ermB -ST695 clone represented 48.1 % of ST695 collected from the province. Continued genomic surveillance of S. pneumoniae serotype 19A is required to: i) track the prevalence and clonal composition of serotype 19A in Québec in future years; ii) characterize the clonal distribution of serotype 19A in adult populations; and iii) monitor whether the currently geographically restricted ermB -ST695 clone observed in Québec expands to OCJs. [ABSTRACT FROM AUTHOR]

• The COVID-19 pandemic has challenged traditional vaccine guidance infrastructure. • NACI made many strategic adaptations to facilitate timely vaccine advice in Canada. • The pandemic highlighted critical roles for NITAGs in vaccine program design. • Learning from COVID-19 pandemic adaptations, we see a roadmap for future pandemics. The COVID-19 pandemic has challenged traditional vaccine guidance infrastructure and frameworks, and added urgency and complexity to the operation of National Immunization Technical Advisory Groups (NITAGs). Canada's National Advisory Committee on Immunization (NACI) provides immunization guidance to the Public Health Agency of Canada (PHAC) who publicly shares expert and evidence-informed guidance with Canadian provinces and territories. Throughout the pandemic, NACI and PHAC implemented many adaptations to meet urgent needs for pandemic vaccine guidance. In this paper, we describe: structural adaptations in response to the accelerated pace and amount of work required to issue recommendations that were timed around product authorizations and dynamic epidemiology; technical adaptations in response to rapidly evolving evidence of variable quality which required close monitoring, and which promoted reliance on basic vaccine principles due to incomplete direct evidence; the need to provide nimble advice (e.g., off-label recommendations, preferential recommendations); communications adaptations (e.g. identify sustainable spokespeople for the committee, receive stakeholder feedback, and ensure urgent nuanced advice was communicated to a diverse audience); and research adaptations focussing on solutions to constrained supply (e.g. prioritisation, extended intervals, and heterologous schedules). The early pandemic vaccine experience has created a roadmap of lessons and adaptations that should be leveraged in future pandemic vaccine programs, and has highlighted the essential role of NITAGs to complement regulatory structures during pandemics to ensure timely, impactful, and evidence-informed public health vaccine guidance. [ABSTRACT FROM AUTHOR]

Unlike other high-income countries, Canada has no national policy for drugs treating rare diseases (orphan drugs). Nevertheless, in 2022, the Canadian government committed to creating a national strategy to make access to these drugs more consistent. Our aim was to study whether recommendations made by the Canadian Agency for Drugs and Technology in Health (CADTH) translated into coverage decisions for orphan drugs in Ontario, the largest Canadian province. This study is the first to look at this question for orphan drugs, which are at the center of policy attention. We included 155 orphan drug-indication pairs approved and marketed in Canada between October 2002 and April 2022. Cohen's kappa was used to test the agreement across health technology assessment (HTA) recommendations and coverage decisions in Ontario. Logistic regression was used to test which factors, relevant to decision-makers, might be associated with funding in Ontario. We found only fair agreement between CADTH's recommendations and coverage decisions in Ontario. Although a positive and statistically significant association between favorable HTA recommendations and coverage was found, more than half of the drugs with a negative HTA recommendation were available in Ontario, predominately through specialized funds. Successful pan-Canadian pricing negotiations were a strong predictor of coverage in Ontario. Despite efforts to harmonize access to drugs across Canada, considerable room for improvement remains. Introducing a national strategy for orphan drugs could help increase transparency, consistency, promote collaborations, and make access to orphan drugs a national priority. • Recommendations by the Canadian Agency for Drugs and Technology in Health do not always translate to provincial coverage decisions for new drugs. • We explored whether Canadian Agency for Drugs and Technology in Health's recommendations are aligned with coverage decisions for orphan drugs in Ontario. • Negative health technology assessment recommendations did not necessarily translate to no pan-Canadian pricing negotiations. • More than half the drugs with negative health technology assessment recommendations were available in Ontario through specialized funds. • A national strategy for orphan drugs could prioritize access to these treatments at a national level and harmonize access, at least to some extent, across Canada. [ABSTRACT FROM AUTHOR]

In 2021, the ten provinces in Canada enacted COVID-19 vaccine mandates that restricted access to non-essential businesses and services to those that could provide proof of full vaccination to decrease the risk of transmission and provide an incentive for vaccination. This analysis aims to examine the effects of vaccine mandate announcements on vaccine uptake over time by age group and province. Aggregated data from the Canadian COVID-19 Vaccination Coverage Surveillance System (CCVCSS) were used to measure vaccine uptake (defined as the weekly proportion of individuals who received at least one dose) among those 12 years and older following the announcement of vaccination requirements. We performed an interrupted time series analysis using a quasi-binomial autoregressive model adjusted for the weekly number of new COVID-19 cases, hospitalizations, and deaths to model the effect of mandate announcements on vaccine uptake. Additionally, counterfactuals were produced for each province and age group to estimate vaccine uptake without mandate implementation. The times series models demonstrated significant increases in vaccine uptake following mandate announcement in BC, AB, SK, MB, NS, and NL. No trends in the effect of mandate announcements were observed by age group. In AB and SK, counterfactual analysis showed that announcement were followed by 8 % and 7 % (310,890 and 71,711 people, respectively) increases in vaccination coverage over the following 10 weeks. In MB, NS, and NL, there was at least a 5 % (63,936, 44,054, and 29,814 people, respectively) increase in coverage. Lastly, BC announcements were followed by a 4 % (203,300 people) increase in coverage. Vaccine mandate announcements could have increased vaccine uptake. However, it is difficult to interpret this effect within the larger epidemiological context. Effectiveness of the mandates can be affected by pre-existing levels of uptake, hesitancy, timing of announcements and local COVID-19 activity. [ABSTRACT FROM AUTHOR]

• Ca. 3.75 Ga gneiss developed a gneissosity prior to ca. 3.3 Ga. • Ferroan, calc-alkaline ca. 3.3 Ga granitoids formed by remelting of Eoarchean crust. • Ca. 3.3 Ga granitoids were intruded by ca. 2.7 granite and by 2.5 Ga granitic dyke. • The magmatic history of the Saglek Block is similar to that of the SW Greenland. The Saglek Block in the Nain Province of northeast Canada is part of the North Atlantic Craton. It comprises Archean gneisses that record magmatic and metamorphic ages between ca. 3.9 and 2.5 Ga. In this study, a grey banded gneiss from Maidmonts Island records an age of 3.72 Ga, which is equated with Uivak I gneisses reported from across the Saglek Block, and contains 3.8 Ga xenocrysts. These rocks were deformed and metamorphosed prior to the intrusion of augen gneiss protoliths on both Maidmonts and Mentzel islands that record U-Pb zircon ages of 3.33 Ga. These rocks are composed of ferroan calc-alkaline granite and granodiorite and were likely generated by partial melting of pre-existing quartzo-feldspathic crust, as attested by the presence of ca. 3.8 Ga xenocrysts. Such augen gneiss was previously classified as ca. 3.6 Ga 'Uivak II gneiss', a term we argue should now be abandoned. The final magmatic events recorded on Maidmonts and Mentzel islands took place in the Neoproterozoic with the emplacement of granitic stocks at ca. 2.72 Ga, and sills and dykes at ca. 2.57 Ga. This sequence of magmatic events from the Eoarchean to Neoarchean is very similar to that recorded in the Itsaq Gneiss Complex of southwest Greenland, where, based on the Hf signature, it has been suggested that a change in tectonic environment resulted from the initiation of subduction at ca. 3.2 Ga. Although Lu-Hf and Sm-Nd isotopic signatures from the ca. 3.33 Ga gneisses have been interpreted in the literature as due to partial melting of Hadean mafic crust, alternatively, they can be generated by partial melting of Eoarchean continental crust in a continental arc setting. We argue this is more consistent with the non-TTG geochemistry of the augen gneisses. [ABSTRACT FROM AUTHOR]

Rates of child removal by child protective services (CPS) in Manitoba are the highest in Canada with a profoundly disproportionate impact on First Nations families. Despite infants constituting the highest proportion of children affected, no research has examined population-level rates of infant contact with CPS. We examined the incidence of infant contact with different levels of CPS, including termination of parental rights (TPR), according to First Nations status. We identified 217,261 infants (47,416 First Nations; 169,845 non-First Nations) born between 1998 and 2014 in Manitoba, Canada and residing in the province until at least age 5. We used linked administrative data to calculate population-level rates of contact with different levels of CPS by First Nations status, including an open file before age 1, out-of-home placement before age 1, and TPR before age 5. Overall 35.8 % of First Nations infants had an open file, 8.5 % experienced out-of-home placement, and 5.4 % experienced TPR. Among other infants, 8.5 % had an open file, 1.3 % experienced out-of-home placement and 0.7 % experienced TPR. The rate of early-stage contact increased the fastest among First Nations infants, with a rise of 22.4 % in our study period, compared to a rise of 1.7 % among all other infants. CPS contact was exceptionally high among First Nations infants compared to other infants, with early-stage contact accelerating most dramatically over time. Findings support calls to greatly reduce the disruption of system contact in the lives of First Nations families. [ABSTRACT FROM AUTHOR]

• Non-zero I/(Ca + Mg) values were detected in Archean and Paleoproterozoic shallow marine carbonates. • The samples are from several locations and range in age from 2.93 to 2.31 Ga. • These non-zero values indicate the original localized presence of dissolved marine oxygen. Marine oxygenation during the Archean and Paleoproterozoic is poorly constrained. Iodine in carbonate is a possible oxygen indicator. We obtained molar ratios of iodine to calcium-magnesium [I/(Ca + Mg)] for 2.93–2.31 Ga from shallow marine Ca-carbonate (limestone, dolostone) platform sediments at several locations in the southern Superior Province in Canada and the USA. Maximum I/(Ca + Mg) ratios obtained are 0.13, 0.26, 0.05 and 0.22 μmol/mol, for 2.93, 2.86, 2.80 and 2.31 Ga samples, respectively. These non-zero carbonate I/(Ca + Mg) ratios indicate localized oxygen in Archean and Paleoproterozoic shallow marine environments. These data support an early origin for biological oxygen-production and, specifically, the idea that mid-late Archean oxygenation was sufficient to facilitate Ca-carbonate precipitation in shallow marine 'oxygen oases' adjacent to anoxic iron-rich seas [ABSTRACT FROM AUTHOR]

• All-cancer radiotherapy utilization ratios (RTUR) varied across Canada by 9%, and up to 28% by cancer type. • RTURs were below Ontario benchmarks for many provinces and cancer subsites. • RTURs can be a reasonable surrogate for linked (patient-specific) utilization. Access to radiotherapy (RT) is a key component of a cancer control strategy. However, radiotherapy utilization (RTU) rates fall short of desired benchmarks in certain Canadian provinces. We aimed to describe provincial variations in RTU across Canada. We calculated radiotherapy utilization ratios (RTUR) for each Canadian province from 2016 (RT case counts divided by incidence counts), by cancer type (all cancers, lung, breast, rectal, prostate) and treatment intent (curative, palliative) where data were available. Data were extracted from each provincial RT data repository, cancer registry and/or RT department. We compared RTURs descriptively across provinces and to Ontario benchmarks, and calculated an estimated national RTUR. In provinces with capacity for data linkage, RTURs were compared to a linked (patient-specific) method of calculating utilization, by linking each incident case to whether RT was received within 1 year of diagnosis (RTU-1 yr). Excluding three provinces that included re-treatments, all-cancer RTURs ranged from 0.31 in Manitoba to 0.40 in Nova Scotia. The national all-cancer RTUR was 0.35, which was comparable to Ontario benchmarks (0.34). Larger variations were seen by cancer type, with an absolute difference in RTURs of 28% for lung cancers, 27% for breast cancers, 21% for rectal cancers, and 18% for prostate cancers. RTURs for nearly all provinces were below established Ontario benchmarks for each cancer type, except prostate cancer. RTURs over-estimated RTU-1 yr by at most 5%, except for prostate cancers where they over-estimated RTU-1 yr by up to 15%. RTU varies by province in Canada, and most notably by cancer subsite. More granular data at the regional level and by healthcare facility is required to further tailor strategies aimed at improving RT access. RTURs also serve as a reasonable surrogate for linked RTU, and both methods can contribute meaningfully to measure RTU depending on the context and data availability. [ABSTRACT FROM AUTHOR]

In Canada, greenhouse gas (GHG) emissions continue to remain high despite the federal government's commitment to reduce GHG emissions. Environmental policy across Canadian provinces has largely lacked consistency with some provinces implementing targeted policy such as carbon taxes while others have strongly resisted the federal government's attempts to encourage such policy. This study examines the impact of environmental policy on GHG gas emissions across Canadian provinces with policy uniquely measured by public and business sector spending on environmental protection as well as notable province-specific policies. An extended STIRPAT model is specified with the inclusion of proxies for environmental policy using panel data from Canada's ten provinces from 1995 to 2019. The cointegration and the error correction modelling approaches are employed to estimate the non-stationary panel data. A pooled mean group estimation is applied to provide short run and long run coefficients. The findings indicate that although per capita GDP is the main driver of GHG emissions in Canada, environmental policy has a significant mitigating effect, as shown by the negative association between emissions and private and public sector spending on environmental protection in the long run. Furthermore, provinces with targeted policies, such as Ontario's coal phase-out and British Columbia's carbon tax, experienced significant emissions reductions. The theoretical implication is the successful addition of policy variables to the STIRPAT model, providing the model a new application for future research. [Display omitted] • Assess the impact of environmental protection policies on per capita greenhouse gas emissions in Canada. • Utilize public and private expenditures on environmental protection, along with provincial policies. • Extend the STIRPAT model to incorporate environmental protection policies in an empirical model. • Demonstrate a significant negative relationship between environmental protection policies and GHG emissions. • Offer insights with implications for global environmental sustainability efforts. [ABSTRACT FROM AUTHOR]

Background Studies suggest that fatty acid status influences breast cancer etiology, yet the roles of individual fatty acids in breast cancer risk are unclear, specifically when central adiposity and menopausal status are considered. Objectives This study examined the associations of fatty acid status with breast cancer risk including location, menopausal status, and waist-to-hip ratio as key variables. Methods Prediagnostic plasma phospholipid fatty acids were measured in women with breast cancer (n  = 393) and age-matched controls (n  = 786) from a nested case-control prospective study within Alberta's Tomorrow Project (ATP) and British Columbia Generations Project (BCGP) cohorts. Binary logistic regression models were used to evaluate associations of fatty acids and breast cancer risk with subgroup analysis for menopausal status and waist-to-hip ratio. Results Women from BCGP had a higher n–3 (ɷ-3) fatty acid status compared with the ATP (6.4% ± 0.08% vs. 5.3% ± 0.06%; P  < 0.001), so subsequent analysis was blocked by cohort. Overall, fatty acids had inconsistent associations with risk. In the ATP among premenopausal women, total long-chain n–3 fatty acids (ORQ4vsQ1 = 1.78; 95% CI: 0.58, 5.43; P- trend = 0.007, P- interaction = 0.07) were positively associated with breast cancer risk, whereas in BCGP, DHA (ORQ4vsQ1 = 0.66; 95% CI: 0.28, 1.53; P- trend = 0.03, P- interaction = 0.05) and total long-chain n–3 fatty acids (ORQ4vsQ1 = 0.66; 95% CI: 0.28, 1.54; P- trend = 0.03) were associated with decreased cancer risk when the waist-to-hip ratio was <0.85. Conclusions Our findings suggest that regional variations in fatty acid status influence breast cancer risk, resulting in positive associations of total long-chain n–3 fatty acids in premenopausal ATP women and negative associations of these fatty acids in BCGP women with a waist-to-hip ratio below guidelines. This study highlights the complexity and difficulty in using fatty acid status to predict breast cancer risk in diverse populations without the consideration of other risk factors. [ABSTRACT FROM AUTHOR]

Objectives: The gold standard of medication abortion, mifepristone and misoprostol, became available in Canada in 2017 as a combination pack under the trade name Mifegymiso®. We aimed to document people's experiences deciding to use and accessing medication abortion and generate insights for how information and services could be improved.Methods: We conducted semi-structured, in-depth interviews with 64 people who had used the mifepristone/misoprostol regimen to induce an abortion in seven different Canadian provinces. We used ATLAS.ti to manage our data, which we analyzed for content and themes using inductive and deductive techniques.Results: The overwhelming majority of participants reflected positively on their experience with mifepristone/misoprostol for early abortion. Most people reported that medication abortion offered increased autonomy, privacy, and convenience compared with instrumentation procedures and especially liked being able to have the abortion in a comfortable and familiar environment. The small number of participants who reflected more negatively on their experiences generally did not feel well informed about what to expect. Several participants reported that the media served as a key information source for finding and accessing services.Conclusions: Although our sample of Canadian abortion patients appear to be highly satisfied with the mifepristone and misoprostol regimen, there are several avenues by which medication abortion care could be improved. Providing more detailed information about pain management and the products of conception and lifting up the voices and stories of those who have used mifepristone and misoprostol could help patients manage expectations and would likely be welcomed.Implications: Changes to the Mifegymiso® product monograph since its introduction seem to have addressed a number of barriers described by early users of mifepristone and misoprostol. Continued engagement with clinicians to ensure that the process is not overly medicalized appears warranted. [ABSTRACT FROM AUTHOR]

The present study empirically investigates whether targeted government spending and environmental policies promote green growth, as measured by greenhouse gas productivity. Government spending for pollution abatement (GEPA) represents non-market environmental policies encompassing both enforcement regulations and stakeholder incentives, while policy dummy represents province specific targeted environmental policies. Using panel data from 1995 to 2020 across ten provinces of Canada, an empirical model based on STIRPAT has been developed and estimated, addressing various econometric issues to ensure the robustness and consistency of the results. The findings confirm that both GEPA and targeted environmental policies are crucial determinants in achieving green growth. Additionally, variables such as business sector expenditures for R&D, the share of renewable energy, per capita GDP, and population also contribute to green growth. These results highlight the importance of the stick-and-carrot approach as a key strategy and policy tool for sustainable development. The implications of these findings extend beyond Canada and hold valuable lessons for emerging and developing countries that predominantly rely on command-and-control regulations without adequate support. To effectively address the challenge of achieving green growth, a coordinated approach that combines targeted government spending and environmental policies, supported by innovation and renewable energy exploration, is essential. Overall, this study's findings have significant implications for environmental sustainability on a global scale. [Display omitted] • Examines the effect of targeted government spending and environmental policies on green growth in Canada. • Uses greenhouse gas productivity as an index of green growth. • Estimates the empirical model developed addressing advanced econometric issues related to panel data for 1995–2020. • Controls renewable energy, innovation, per capita income, population. • Have significant implications for environmental sustainability on a global scale. [ABSTRACT FROM AUTHOR]

Through survey and focus groups in two provinces in Canada misunderstanding and confusion surrounding Low-Dose Ionizing Radiation (LDIR) is explored specifically surrounding medical procedures, risk, and benefits. Generally people associated the word radiation with harm, but when asked participants were not concerned about LDIR. Approximately equal numbers (40%) thought LDIR was 'difficult' as those that thought it was 'easy' but research results reveal confusion about the definition of and sources of LDIR. Most people believed the benefits of LDIR outweighed the risks. Further, many had inaccurate views of 'high' dose radiation. Scientists and the Canadian regulator were determined to be the most trusted sources of information while elected officials and industry representatives the least trusted. Participants wanted more information on whether LDIR was a problem in Canada, what the risks were associated with it, as well as the applicable protections, rules and regulations. Focus group participants expressed a preference for face-to-face exchange of information, but mass media remains an important source of information as the first-place people check for answers. Future research surrounding behavioural science and LDIR communications, and deep LDIR science communication will be important in addressing this issue. • People do not have high levels of knowledge of low dose ionizing radiation (LDIR). • Most people respond well to the term LDIR and believe benefits outweigh negatives. • Scientists are most trusted communicators followed by the regulator. • Some participants wanted more information surrounding radiation. [ABSTRACT FROM AUTHOR]

The Proterozoic evolution of Laurentia involved intermittent orogens and arc-related crustal growth along a modern-style convergent margin, termed the Great Proterozoic Accretionary Orogen (GPAO). The major lithotectonic provinces of the GPAO in the United States are exposed as telescoped equivalents within the thrust stack of the Grenville Province in Canada. We report zircon U Pb and Lu Hf isotope analyses for two orthogneisses and one quartzite from Archean and Paleoproterozoic domains in the gneiss belt of the SW Grenville Province, Canada. The data constrains Paleoproterozoic crustal growth and sedimentation for this part of the Laurentian margin. The orthogneisses have similar zircon U Pb and Lu Hf isotope systematics that reflect igneous reworking (ca. 1700–1660 Ma) of a Penokean aged (ca. 1.9 Ga) depleted mantle derived source, along with metamorphic reactivation at both ca. 1.45 Ga and during the Grenville Orogeny (1.2–1.0 Ga). The quartzite has a bimodal Paleoproterozoic (2.1–1.8 Ga) and Archean (> 2.5 Ga) detrital zircon age spectrum. The Paleoproterozoic detrital zircon grains have a wide range of Hf(t) compositions (εHf(t) = −12.5 to 10) reflecting co-eval interaction of Archean and depleted Paleoproterozoic sources, contrasted by a more restricted range for the Archean population (εHf(t) = −7 to 4). The new data support the presence of reworked ca. 1.9 Ga depleted mantle sources in the Paleoproterozoic Parautochthon, which extend further east than previously thought. They also identify correlations amongst detrital zircon age spectra and Hf isotope compositions in quartzites from different locations of the Archean Parautochthon. • Juvenile Penokean sources (∼1.9 Ga) extend into the SW Grenville Province. • Penokean (∼1.9 Ga) crust-mantle mixing recorded by detrital zircon Lu Hf isotopes. • Erosion and redeposition of sedimentary sinks can mask orogen detrital systematics. [ABSTRACT FROM AUTHOR]

New whole-rock Sr-Nd-Pb-O isotope data are combined with previously published results for Sr and Nd isotopes and major and trace element chemistry to examine the petrogenetic and tectonic environments of a suite of ca. 980 Ma potassic to ultrapotassic dykes (PUD) from the Canyon domain, central Grenville Province in Canada. The PUD suite can be divided into two geochemically distinct groups that exhibit characteristic source mineralogy, depth of partial melting, and multi-stage metasomatism of heterogeneous mantle sources. Major and trace element data suggest involvement of both fertile and depleted sources involving spinel and garnet peridotite, while trace element and isotope data indicate long-term LREE and LILE enrichments and HFSE depletions in ancient subduction settings. Low time-integrated Rb/Sr, Sm/Nd, and U/Pb ratios suggest enriched mantle EM-I metasomatized by ancient subduction of continental upper crust and/or carbonate sediments. A latest phase of fluid/melt metasomatism is attributed to a late-Grenvillian intracontinental subduction and limited lithospheric extension. The late-Grenvillian tectonic setting is proposed here to be characterized by shallow-angle underthrusting of the foreland beneath the Grenvillian hinterland, where SCLM, initially of Proterozoic age and eventually of Late Archean age, became transported beneath the orogenic core. The intracontinental collision was short-lived and probably terminated because of buoyancy constraints related to the refractory character of the subducted Archean lithospheric mantle. • Late Grenvillian potassic to ultrapotassic dykes from the orogenic hinterland in Canada are geochemically and isotopically characterized. • Late Archean and Proterozoic lithospheric mantle sources record ancient subduction metasomatism and late fluid metasomatism prior to dyke emplacement. • Tectonic setting characterized by shallow-angle or flat underthrusting of the foreland lithosphere beneath the hinterland. [ABSTRACT FROM AUTHOR]

• Carrot Rewards is a free, incentive-based, smartphone health app available in participating Canadian provinces. • An in-app quiz educated users about the importance of the influenza vaccine and promoted pharmacy influenza clinics. • The app used novel "push" notifications when the user was within 200 m of the sponsored pharmacy. • The quiz completion rate was high although only a small number visited the pharmacy. • Loyalty point incentives did not appear to influence pharmacy visits. Carrot Rewards is a free, incentive-based, smartphone health app available in participating provinces in Canada. One feature of Carrot was designed to incentivize influenza vaccine education messages and encourage vaccine uptake for users in the province of British Columbia. This study aimed to evaluate the uptake of the Carrot Flu Campaign educational quiz and to determine if mobile "push" notifications, plus loyalty point incentives, resulted in users visiting a sponsored pharmacy to discuss and receive the influenza vaccine. The Carrot Flu Campaign delivered an in-app quiz, educating users on the importance of the influenza vaccine. Push notifications were then sent to users when they came within 200 m of a sponsored pharmacy. Those who visited the pharmacy collected bonus points and completed a follow up quiz tracking influenza vaccine behaviour. A sub-sample of users completed the Flu Campaign between their baseline and follow up Health Risk Assessment (HRA), a survey which asked about influenza vaccine uptake behaviour. Descriptive statistics were summarized. A total of 38.1% (30,538/80,228) registered Carrot users completed the Flu Campaign quiz. Of those in participating cities (n = 21,469), 41% clicked on the map to show the nearest sponsored pharmacy and 78% enabled their smartphone's "locations" feature, allowing them to receive the push notifications. A small number of users spoke to a pharmacist (n = 96) and less than half reported receiving the influenza vaccine (38/96; 39.6%). From the HRA sub-sample (n = 3693), approximately 5% more users reported receiving the influenza vaccine during the 2017 influenza season compared to the previous year. Carrot Rewards used a novel delivery method to educate the general population and showed geolocation could be used to facilitate influenza vaccine uptake. Future iterations could tailor content to target those most at risk and should consider more robust evaluation methods to determine the app's effectiveness. [ABSTRACT FROM AUTHOR]

Introduction: This study sought to estimate the number of illicit retailers and the average price of cannabis in the largest municipality in each province and territory in Canada by obtaining information from retailers.Methods: Online search engines were used to identify retailers in each municipality. The advertised prices for various volumes of the least expensive, most expensive, and most popular dry herb were determined using the retailer's website, Weedmaps, or Leafly. Data was collected between October 2017 and May 2018, including two waves in Toronto to examine changes over a five-month period.Results: Across the 13 municipalities, 997 cannabis retailers were identified, including 215 physical storefronts. The average price per gram of cannabis was $10.02, $7.80, and $12.30 for the most popular, least expensive, and most expensive strains, respectively. The price-per-gram decreased as purchase volume increased: purchasing one-eighth of an ounce and one ounce of cannabis led to savings of up to 9% and 27%, respectively. Prices were consistent across municipalities, although the number of outlets varied greatly. Prices were similar between storefronts and delivery-only services; however, delivery services offered larger discounts for cannabis purchased by the ounce. The five-month comparison in Toronto revealed modest changes in the number of retailers and more pronounced changes in the price of the most popular and least expensive strains.Conclusion: The findings depict a well-established retail cannabis market in Canada in the year prior to legalization. The average advertised price of the most popular cannabis varieties was approximately $10, which aligns with the projected retail price of cannabis from licensed sources following legalization in Canada. [ABSTRACT FROM AUTHOR]

• A novel bridge weigh-in-motion method is presented using parametric dynamic bridge-vehicle interaction formulation. • Modal parameters extracted from ambient vibration tests are used to accurately simulate the bridge structures. • The formulation offers superior computational efficiency since it eliminates the need for calibrated finite element models. • The proposed method resulted in accurate estimations even when the vehicle travel path differs from calibrations. • The Proposed method was validated using a full-scale case-study arterial highway bridge in Canada. Dynamic bridge weigh in motion systems use models that can simulate the dynamic behaviour of a bridge subjected to moving traffic. Currently available models use complex and computationally expensive Moving Force Identification (MFI) methods that utilize finite element models to estimate the bridge torsional and transverse dynamic behaviour. This paper presents a novel dynamic parametric BWIM method that utilizes the experimentally estimated modal parameters for simulating the response of a bridge structure to moving loads. The estimated modes of an in-situ structure inherently capture the true bridge behaviour for any generalized geometry, boundary conditions and load position. Therefore, it enables the complex torsional and transverse bending behaviour of the bridge to be captured. In this paper, the mathematical derivation of the analytical model is presented in detail, then model calibration and weighing procedures are outlined, followed by the validation of the proposed method using a full-scale case study arterial highway bridge in the Canadian Province of New Brunswick. The proposed dynamic BWIM method offers a novel solution for the development of real-time BWIM systems that is efficient to calibrate and accurate in vehicle identification. [ABSTRACT FROM AUTHOR]

Introduction: In 2012, 10% of Canadians used cannabis and just under half of those who use cannabis were estimated to have driven under the influence of cannabis. Substantial evidence has accumulated to indicate that driving after cannabis use increases collision risk significantly; however, little is known about the extent and costs associated with cannabis-related traffic collisions. This study quantifies the costs of cannabis-related traffic collisions in the Canadian provinces.Methods: Province and age specific cannabis-attributable fractions (CAFs) were calculated for traffic collisions of varying severity. The CAFs were applied to traffic collision data in order to estimate the total number of persons involved in cannabis-attributable fatal, injury and property damage only collisions. Social cost values, based on willingness-to-pay and direct costs, were applied to estimate the costs associated with cannabis-related traffic collisions. The 95% confidence intervals were calculated using Monte Carlo methodology.Results: Cannabis-attributable traffic collisions were estimated to have caused 75 deaths (95% CI: 0-213), 4407 injuries (95% CI: 20-11,549) and 7794 people (95% CI: 3107-13,086) were involved in property damage only collisions in Canada in 2012, totalling $1,094,972,062 (95% CI: 37,069,392-2,934,108,175) with costs being highest among younger people.Discussion: The cannabis-attributable driving harms and costs are substantial. The harm and cost of cannabis-related collisions is an important factor to consider as Canada looks to legalize and regulate the sale of cannabis. This analysis provides evidence to help inform Canadian policy to reduce the human and economic costs of drug-impaired driving. [ABSTRACT FROM AUTHOR]

There is strong evidence for climate change leading to a rise in temperatures and a change in precipitation trends. These environmental changes pose a threat to pavement infrastructure worldwide. Therefore, it is necessary to modify pavement design procedures to consider climate change. In addition, it is necessary to consider suitable pavement materials for future climate. The objective of this study is to develop a framework for selecting an appropriate adaptation strategy to mitigate climate change impact. To fulfill this, the influence of climate change on long-term pavement performance in Canada has been quantified over sixteen Canadian pavement sections located over various provinces in Canada. In addition, the fundamental causes of pavement deterioration due to climate change were determined using ten different climate change models. Various adaptation strategies such as upgrading asphalt binder grade, increasing the thickness of asphaltic concrete layer, increasing the base layer thickness, and using stabilized base layers were analyzed to reduce pavement deterioration and to extend the service life of the pavement. Unlike the other studies, pavement temperatures were determined using Enhanced Integrated Climate Model (EICM) to determine the change in binder grade for the future climate in the adaptation process. The study found that by 2070 all examined locations will require an upgrade in binder grade and the majority will require an upgrade in mixture gradation. Furthermore, the east and west coast will be more vulnerable to climate change and require additional measures in comparison to Central Canada. Newfoundland and Prince Edward Island are the only locations that will need to consider a change in asphalt thickness while British Columbia is the only location eventually requiring a stabilized base. This study emphasizes the necessity of climate change adaptation strategies for Canadian asphaltic concrete pavements. [Display omitted] • Different combinations of adaptation strategies are necessary at each location. • The Canadian coasts generally require more adaptation measures than Central Canada. • By 2070, all Canadian provinces will require an upgrade in asphalt binder. [ABSTRACT FROM AUTHOR]

In terms of energy resources, Canada is an important player on the world scene. However, the energy systems of the Canadian provinces and territories are much diversified and a national energy strategy is missing in order to optimize the management of energy systems. The objective of this paper is twofold. First, we introduce TIMES-Canada, a new multi-regional energy model that has been developed using the most advanced TIMES optimization modeling framework, while keeping a very high level of details in the database (5000 specific technologies; 400 commodities) compared with other Canadian energy models. Second, we define and analyze possible futures for the Canadian integrated energy system on a 2050 horizon, under five different baselines: a Reference scenario as well as four alternate scenarios corresponding to different oil prices (Low and High) and socio-economic growth trends (Slow and Fast). In our Reference scenario, we show that the Canadian final energy consumption is expected to increase by 43% between 2007 and 2050. The Fast scenario leads to the maximum increase compared with the Reference scenario (21% in 2050). In all scenarios, oil products will continue to dominate on the long term, although in a decreasing proportion over time (from 43% in 2007 to 29% in 2050) in favor of electricity (31% of the additional demand in 2050) and biomass/biofuels. Regarding the corresponding optimal energy production paths, we illustrate two main trends: (1) a gradual replacement of onshore conventional oil & gas sources by unconventional and offshore sources (oil sands is expected to represent half of the production in 2050), and (2) a significant penetration of renewables in the electricity mix is shown after 2035 due to increases in oil import prices and decreases in renewable technology costs. The development and calibration of such a detailed technology-rich model represent an important contribution for Canada: TIMES-Canada is the only optimization model covering in details the large diversity of provincial energy systems on a long term horizon. [ABSTRACT FROM AUTHOR]

Meeting commitments to the Paris Agreement will necessitate a transition in Canada's power system including increased generation from renewable sources. This study analyzes the Canadian electricity system in terms of its readiness to operationalize decarbonization strategies. More specially, this paper evaluates potential of Canada's electricity system in terms of the flexibility required to integrate variable renewable energies (VREs). To do so, the SILVER production cost model (PCM) is refined to improve its representation in terms of hydro resources, demand response programs and price-setting mechanism. Next, a network-constrained unit commitment (NCUC) of SILVER is built for each of Canada's ten provinces for a one-year period based on 2018 data. The results are used to assess the system flexibility and transmission network sufficiency as well as operational aspects including costs and emissions. The results indicate the SILVER's improved hydro modelling enhances the result of operation model by 4% on average. Also, the results demonstrate high flexibility of Canada's hydro-dominated network side along with free capacity in the transmission network can realize 54% VREs penetration rate on average for VREs curtailment less than 10%. In addition, implementation of demand side programs improves the VREs penetration rate by 2%–6% on average. • A Canadian electricity network operation model, SILVER, is improved. • The first suite of operation model of Canada's provinces is built. • Flexibility of Canada's electricity system is assessed. • Potential of Canada's electricity system for VREs integration is analyzed. • Impact of demand response programs on VREs integration is evaluated. [ABSTRACT FROM AUTHOR]

[Display omitted] • Late Archean granitic plutons in northeastern Superior Province have diverse sources. • Four granitic suites record transition from plume-dominated regime to plate tectonics. • The ∼2730–2700 Ma subduction-related plutonism is the major crustal growth event. • The transition between tectonic regimes occurred over a short time span of 30 My. • The transition was markedly diachronous across the Superior Province. The Superior Province in Canada represents an excellent natural laboratory to test various models of crustal growth and evaluate tectonic regimes during the late Archean. Here, we present new geochemical and geochronological data for ca. 2.8–2.7 Ga plutons intruding different lithotectonic units of the north-eastern part of the Superior Province that demonstrate a complex nature and evolution of magma sources in relation to a changing tectonic setting. Four distinct plutonic suites were newly identified: (1) sodic tonalite–diorite (TD) with a composition resembling low-pressure TTG-like melts, (2) sodic tonalite–granodiorite–diorite (TGD) with medium/high-pressure TTG-like signatures, (3) Mg–K-rich monzogranite to monzodiorite (sanukitoids; MMD), and (4) K-rich granodiorite–granite–monzogranite (GGM). These suites are interpreted as recording a temporal evolution from plume-assisted melting of lower mafic continental crust through melting of a subducted oceanic slab at different depths to large-scale re-melting of the previously formed and amalgamated crustal units. In this evolutionary scheme, the ∼2730–2700 Ma subduction-related plutonism is the most voluminous addition of the juvenile arc material and thus represents the most significant crustal growth event. Altogether, the above inferences and published data suggest that the late Archean plutonism in the Superior Province formed during a transitional regime from plume-dominated to plate-tectonic over a short time span between ∼2730 and ∼2700 Ma and that this transition was markedly diachronous across the Province. [ABSTRACT FROM AUTHOR]

Introduction: Despite the proven benefit of adjuvant androgen deprivation therapy (ADT) for patients receiving primary radiation, there are few studies evaluating adjuvant ADT after prostatectomy. In the absence of evidence, opinions and practice patterns vary. We surveyed Canadian prostate cancer surgeons about their use of adjuvant ADT and their opinions on the design of a potential adjuvant ADT trial.Methods: An electronic survey was devised and distributed using a modified Dillman approach. The survey was sent to 38 Canadian urologists that perform radical prostatectomy and representing all 17 major academic institutions in Canada and all 10 Canadian provinces. Reminders were sent three and four weeks following the original request. In addition to demographic information, we asked surgeons about their current use of postoperative adjuvant ADT and their opinion about the need for a clinical trial. To inform trial design, we asked respondents their opinions about which patients should be eligible, what duration of ADT was most appropriate, and which outcomes are clinically meaningful. The survey was sent in February 2020 and all responses were received by March 2020.Results: All 38 (100%) invited urologists completed the survey. Only 3 (7%) respondents currently offer postoperative adjuvant ADT as an option for patients without metastases. 35 (92%) urologists believed that a trial is needed before short-term adjuvant treatment should be offered to prevent recurrence. 15 (45%) urologists believed an adjuvant ADT trial was most appropriate for patients with an estimated PSA recurrence risk of >25% and 16 (42%) believed a recurrence risk of >50% was most appropriate. 25 (66%) respondents believed 12-month was the optimal duration of treatment with adjuvant ADT for a randomized trial. 37 (97%) respondents felt that prolonging the time to PSA recurrence and/or pelvic radiation was a clinically important outcome. The majority (20; 53%) of respondents would recommend 12 months of adjuvant ADT in their practice if a randomized trial showed a 50% relative risk reduction in PSA recurrence at 5-year postoperative.Conclusion: The vast majority of Canadian prostate cancer surgeons do not offer adjuvant ADT following prostatectomy in patients without metastases. Based on the results from this survey, a randomized trial was considered warranted and feasible, and would influence patient care. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Test the Cantor and Land (1985) model using multiple measures of the state of the economy. Methods: A panel data set of the 10 Canadian provinces, 1981 – 2009, is analyzed using a hybrid modeling approach called a decomposition model. Rather than one economy-related model, four are included in the analysis: gross provincial product, gross provincial product per capita, unemployment rate, and low income. Results: All economy-related variables matter for property and violent crime, but the sign and magnitude of the estimated parameters vary based on context. Conclusions: The relationship between the economy and crime is complex. Only including one economy-related variable appears to result in omitted variable bias. As such, any evaluation of the relationship between the economy and crime must consider multiple measures of the economy. [Copyright &y& Elsevier]

Abstract: In 2009, the Public Health Agency of Canada (PHAC) provided guidelines about which groups should be given first access to the H1N1 influenza vaccine. These guidelines recommended that people under 65 with chronic health conditions should be among the first groups to receive the H1N1 influenza vaccine. Severe obesity was among the relevant chronic health conditions identified by PHAC. Since health care is under the jurisdiction of the ten Canadian provinces, the provinces were not required to follow these recommendations in their respective mass vaccination campaigns. Only one province (Manitoba) followed the PHAC recommendations with respect to severe obesity. Four provinces did not offer early vaccination to this group. Other provinces listed severe obesity as a sequencing category late in the vaccination campaign or placed narrow age restrictions on those who were given early access. This commentary argues that the Canadian provinces demonstrated an ambiguous commitment to the early vaccination of people who were severely obese, and that there is evidence that the stigma of obesity influenced H1N1 influenza vaccine sequencing decisions in many Canadian provinces. [Copyright &y& Elsevier]

Abstract: In the current context of health care, health professionals'' accountability obligations may be more extensive than the degree of autonomy that they are permitted to exercise. To date, how professionals fulfil their obligations with regard to this potential for dissonance has not been investigated. The purpose of this Grounded Theory study was to examine how one professional group, occupational therapists, enacted their accountability obligations within their current practice context. Interviews with 21 therapists across three practice sectors in one Canadian province elicited a detailed portrait of the contextual elements within which accountability enactment took place, and a view of the dynamic interplay of these elements with the decision-making involved in fulfilling professional accountabilities. Practitioners moved back and forth between conscious juggling of accountability expectations and more automatically applying tacit practice knowledge. Beyond non-negotiable bottom line commitments to their formal ethical obligations and to retaining autonomy for their clinical recommendations, practitioners'' decisions reflected the goal of doing their best. However, participants'' efforts to find a balance between satisfactorily fulfilling their obligations and acknowledging the frequently unavoidable reality of contextual constraints elicited inconsistent patterns. The study findings raise concerns about ensuring quality of services and the impact on professionals. Although practitioners have an important role to play in addressing these challenges, other stakeholders, for example, the professional regulatory bodies, also must play a role in creating a coherent accountability framework. Further research is needed to obtain greater understanding of professional accountability enactment across health professions, practice sectors and health jurisdictions, and to explore managerial and professional regulatory bodies'' perspectives, roles and responsibilities. [Copyright &y& Elsevier]

Abstract: An analysis of the potential to reduce greenhouse gas emissions in the residential sector by using hydrogen energy is reported. The residential sectors in provinces across Canada are considered. Greenhouse gas emissions are determined from the consumption of fossil fuels associated with the energy requirements in the residential sector. The use of hydrogen technologies in the residential sector is compared to conventional systems. The results are determined to vary by province, with the greatest attainable annual reductions in greenhouse gas emissions observed for heating to be in Alberta (7.2t CO2) and for power generation to be in Saskatchewan (7.2t CO2). The results suggest that hydrogen technologies for heating and power generation are promising options for reducing greenhouse gas emissions in Canada and its provinces. [Copyright &y& Elsevier]

• Recurrent neural networks can effectively identify dairy cows with mastitis. • Including additional variables improves detection over milk characteristics alone. • Within-day changes in behaviour and milk are key indicators of mastitis onset. • Between-farm variability is likely a major limiter for model generalizability. Mastitis is the most important disease in the dairy industry. With widespread adoption of automated milking systems (AMS) in Canada, there is an increasing need for automated detection of mastitis in AMS farms. The main objective of this study was to develop a recurrent neural network (RNN) model for the detection of clinical mastitis (CM) in dairy cows on farms using AMS. Producer-recorded treatment records and AMS data were collected over 3 time periods from a total of 89 dairy farms in 7 provinces across Canada. In addition to developing effective models for the detection of CM, our study also evaluated different windows around the day of diagnosis when the cow would be considered CM-positive to guide practical implementation of models. We also compared numerous subsets of variables including milk and behavioural characteristics, cow traits and farm-level/environmental variables to determine their importance and impact on model performance. Data were randomly divided into a training and a hold-out test set, consisting of all records from 66 and 23 farms, respectively. A 10-fold internal cross-validation was also employed on the training set for model development. When comparing different windows of time around diagnosis, considering animals as CM-positive for 3 d prior to recorded diagnosis resulted in the most timely and effective detection of CM with a per-case sensitivity of 89.8% (range: 83.3–96.0%), and per-day specificity of 84.3% (range: 83.4–85.8%) over the validation folds. These levels of sensitivity and specificity were achieved when using all recorded variables and their daily variances, although the inclusion of behavioural variables and farm-level/environmental variables provided marginal performance improvement over using milk traits alone. Performance of the model was worse on the hold-out test set with a per-case sensitivity of 83.5% (range: 77.9–86.3%) and a per-day specificity of 80.4 % (range: 78.1–82.4%), likely due to farm-specific heterogeneity not encountered in the training data. Over 90% of cases of severe CM (defined by an increase in milk temperature over the pre-CM baseline) were identified by the model, indicating effective performance for the detection of CM requiring the most immediate treatment. Somatic cell count, daily variance in milking interval and milk temperature were identified as the 3 most important variables defined by their impact on model predictions. In addition to milking traits, 8 of the top 20 variables were behavioural measurements, suggesting they can play a role in the detection of CM. Daily variances also represented 8 of the 20 most important variables indicating that CM onset may be associated with sudden, within-day changes in the animal. In conclusion, this study demonstrates that RNNs are able to effectively detect CM by integrating a number of variables that are regularly measured on AMS farms but have typically been excluded from CM detection models. [ABSTRACT FROM AUTHOR]

Background: This study estimated the relationships between increases in legal cannabis stores, legal cannabis sales, and cannabis prevalence in Canadian provinces between 2018 and 2020.Method: Government data were used to calculate changes in licensed store numbers, retail sales dollars, and past-three-month users in 10 provinces across six time periods. The resulting N = 60 observations were standardized per million residents aged 15 and up, and then analyzed via linear regression.Results: Store growth explained 46.3% of the variation in provincial sales growth; each added store was associated with added quarterly sales of $305 (95% CI: $208 to $402) thousand. By contrast, store growth explained only 7.7% of the variation in provincial user growth; each added store was associated with 696 (95% CI: 58-1334) added users.Conclusion: From 2018 to 2020, Canada's rapid cannabis retail expansion was strongly related to legal sales growth but only weakly related to prevalence growth. This implies prevalence growth during that period was related more to legalization's other aspects and/or to the continuation of already-existing trends. [ABSTRACT FROM AUTHOR]

Abstract: This paper uses the aggregate data from the Public Use Microdata Files (PUMF) of Canadian National Population Health Survey to estimate income related health inequalities across the ten Canadian provinces. The unique features of the PUMF allow for a meaningful cross-provincial comparison of health indices and their measured inequalities. It concludes that health inequalities favouring the higher income people do exist in all provinces when health status is either self assessed or measured by the health utility index. Moreover, it finds considerable variations in measured health inequalities across the provinces with consistent rankings for certain provinces. [Copyright &y& Elsevier]

Abstract: Rocks exposed in the MacQuoid-Gibson Lakes region, northwest Hearne subdomain, western Churchill Province, Canada comprise three major lithotectonic assemblages: the Principal volcanic belt; the metasedimentary MacQuoid homocline and; the Cross Bay plutonic complex. Neoarchaean supracrustal rocks of the belt range in age from <2745 to <2672Ma and were intruded during the interval <2689 to 2655Ma by diverse plutonic units ranging from gabbro through syenogranite, but greatly dominated by tonalite. Volcanic rocks occur only in the Principal volcanic belt and the MacQuoid homocline, are metamorphosed to amphibolite facies and vary from rare pillowed to common massive basalt and andesite, intercalated with less abundant, thin, dacitic to rhyolitic tuffs, lavas and volcaniclastic rocks. Basalt and andesite are dominated by subalkaline, FeOT-rich tholeiites with less common calc-alkaline rocks with higher SiO2 contents and variable trace element contents. Felsic volcanic rocks exhibit calc-alkaline affinities and similarly diverse trace element abundances. The diverse trace element chemistry of the basalt and andesite supports their derivation from a heterogeneous mantle source(s) capable of generating MORB-, Arc-, BABB- and boninite-like rocks. Two geochemically distinct, arc-like suites were generated through contamination of the primary mantle-derived magmas either via assimilation of lower or middle tonalitic crust, or through contamination of their mantle source through subduction. Geochemical features of the felsic volcanic rocks indicate that these formed via both anatexis of crust in the amphibolite±garnet stability field and via fractionation of more primitive progenitors in mid-upper crustal magma chambers. ɛNd t =2680Ma isotopic compositions cluster near depleted mantle, indicating that significant incorporation of older, >2700Ma crust likely did not occur. ɛNd t =2680Ma values for three specimens, one from each of the Arc-like suites and one BABB-like basalt are slightly lower than the remainder, suggesting very minor incorporation of slightly older crust. These features imply that the processes that generated the MacQuoid supracrustal belt required simultaneous tapping of geochemically distinct mantle reservoirs with concomitant anatexis of sialic crust (garnet stability field) and fractionation of felsic magmas in upper crustal magma chambers. Shallow water deposition of abundant volcaniclastic rocks and semipelite along with minor conglomerate and quartzite was broadly contemporaneous with this magmatism. We envisage a geodynamic setting characterized by tectonomagmatic processes similar to those of modern supra-subduction zone back-arc marginal basins such as the Sea of Japan. Therein, an extensional, back-arc setting, likely proximal to continental crust, provides an explanation for a broad swath of diverse mantle-derived rocks intercalated with less common felsic rocks as well as an abundance of immature clastic metasedimentary rocks. [Copyright &y& Elsevier]

On-site carbon capturing, storage, and utilization (CCSU) has proven its' potential to reduce CO 2 emissions from large-scale fossil fuel combustion systems. However, the integration of CCSU in community-scale on-site energy generation applications such as district energy systems has not been comprehensively explored in literature. This study aims to propose a life cycle thinking-based framework to compare and prioritize emission reduction strategies that include CCSU and renewable energy technologies to develop zero-emission community energy systems. The framework incorporates multi-criteria decision-making approaches to rank and prioritize community energy emission mitigation strategies. A scenario-based method was employed in assessing the performance of CCSU technologies along with other compatible alternative energy choices. The framework was demonstrated for all the provinces in Canada. Results show that CCSU is more favorable for regions with high dependence on fossil fuel-based energy sources. CCSU could reach the commercial scale if the cost of emission avoided drops below the cost of CO 2 emissions.. The findings of this study are geared towards providing practical decision-support tools for stakeholders who hold responsible for policy and investment decisions in community energy. The developed framework is a generalized technique that provides the flexibility to be employed in any location across the globe. • Emission planning based on techno-economic and environmental performance. • Prospect of CCSU rises if cost of emission reduction drops below cost of emissions. • Cost of infrastructure takes up more than 70% of overall CCSU project costs. • Energy mix, carbon tax, and infrastructure impact emission planning decisions. [ABSTRACT FROM AUTHOR]

Objective: Retail availability of cannabis has the potential to influence demand for both legal and illegal cannabis. The aims of the study were to: 1) estimate the percentage of consumers who report purchasing dried flower legally; and 2) examine the association between purchasing dried flower legally and retail availability, where retail availability was represented as: a) Canadian province; b) 'objective' retail proximity; and c) self-reported retail proximity.Methods: Data come from Canadian respondents in Wave 2 of the International Cannabis Policy Study (ICPS) conducted one year after non-medical cannabis legalization in September-October 2019. Respondents were 18+ years in Alberta/Quebec and 19+ years elsewhere and had purchased any dried flower in the past year (n = 2506). Respondents were recruited through commercial online panels. Weighted binary logistic regression models examined likelihood of purchasing dried flower legally.Results: Overall, 47.7 % of past-year dried flower purchasers reported last purchasing dried flower legally, with variation across provinces (range = 40.5 %-81.2 %). Likelihood of purchasing dried flower legally was greater among those who lived closer to a legal retail store based on Euclidean distance (<3 km vs. > 10 km: AOR = 1.56, 95 % CI: 1.20,2.02), and who had shorter self-reported travel time to a retail store (<5 min. vs. > 15 min.: AOR = 2.24, 95 % CI: 1.56,3.21).Conclusion: One year after legalization, retail availability was associated with last purchasing dried flower legally among past-year dried flower purchasers. To our knowledge, the current study is among the first to examine the legality of purchase source used for dried flower and retail availability of cannabis in Canada post-legalization. [ABSTRACT FROM AUTHOR]

• A novel optimization model to maximize energy for short-term hydropower unit commitment is proposed. • A MILP formulation based on the efficiency curves is established. • The optimized solutions can be directly implemented in practice. • A real case study in Canada shows benefits of optimal solutions compared to historical decisions. This paper presents a linear mixed-integer formulation to solve the short-term hydropower unit commitment problem. It uses the pair of maximum efficiency points of water discharge and the power produced at the maximum storage for all possible combinations of turbines. The goal is to maximize total energy production for all periods. The objective function is calculated using the correction between the power produced at the current volume and the maximum storage and penalizes unit start-ups. Constraints on the maximum number of turbine changes are imposed to find a viable solution. Computational results are reported for 65 instances with two powerhouses of five turbines each located in the Saguenay-Lac-St-Jean region of the province of Quebec in Canada. [ABSTRACT FROM AUTHOR]

Displacement of fossil fuels by forest bioenergy can contribute to climate change mitigation by reducing greenhouse gas (GHG) emissions. However, GHG savings are not realised until the avoided fossil emissions offset the loss of atmospheric carbon (C) that would have been sequestered if the biomass was not used for bioenergy (i.e. time to C sequestration parity). We estimated the potential for mitigating GHG emissions and the timing of these atmospheric benefits when substituting conventional natural gas (NG) with renewable natural gas (RNG) produced from different forestry feedstocks within three Canadian provinces, and assessed the uncertainty among these estimates. We calculated the GHG balance of RNG using the alternative fate of biomass and the use of NG as base-case scenarios. Immediate to long-term time to C sequestration parity was typically in the order of residues burned < mill residues < harvest residues decaying on site < salvaged trees. The potential GHG savings from using harvest and mill residues to produce RNG within the three provinces ranged from 52.4 to 77.8 Mt CO 2eq a−1. Sensitivity analyses suggest that time to C sequestration parity in the best-case scenarios relative to the baseline can be reduced up to 17 years by using harvest residues that decay rapidly (based on feedstock species, size and geographic region), and reduced up to 8 years by improving the efficiency of the thermochemical conversion process. These two considerations are key for ensuring significant GHG reductions from RNG use within a timescale that helps Canada meet its GHG mitigation targets. • Immediate GHG benefits for RNG produced with residues otherwise burned on site. • No short-term C sequestration parity time for RNG produced with forest residues. • C sequestration parity time >100 years for RNG produced with salvaged trees. • Potential net GHG savings of 52.4–77.8 Mt CO 2eq.year−1 for RNG use. [ABSTRACT FROM AUTHOR]