Locations In Ontario Research Articles

Modelling Climate Effects on Site Productivity and Developing Site Index Conversion Equations for Jack Pine and Trembling Aspen Mixed Stands

Forest site productivity estimates are crucial for making informed forest resource management decisions. These estimates are valuable both for the tree species currently growing in the stands and for those being considered for future stands. Current models are generally designed for pure stands and do not account for the influence of climate on tree growth. Consequently, site index (SI) conversion equations were developed specifically for jack pine (Pinus banksiana Lamb.) and trembling aspen (Populus tremuloides Michx.) trees grown in naturally originated mixed stands. This work involved sampling 186 trees (93 of each species) from 31 even-aged mixed stands (3 trees per species per site) across Ontario, Canada. Stem analysis data from these trees were utilized to develop stand height growth models by incorporating climate variables for each species. The models were developed using a mixed effects modelling approach. The SI of one species was correlated with that of the other species and climate variables to establish SI conversion equations. The effect of climate on site productivity was evaluated by projecting stand heights at four geographic locations (east, center, west, and far west) in Ontario from 2022 to 2100 using the derived stand height growth models. Height projections were made under three emissions scenarios reflecting varying levels of radiative forcing by the end of the century (2.6, 4.5, and 8.5 watts m−2). Climate effects were observed to vary across different regions, with the least and most pronounced effects noted in the central and far western areas, respectively, for jack pine, while effects were relatively similar across all locations for trembling aspen. Stand heights and SIs of jack pine and trembling aspen trees grown in naturally originated mixed stands can be estimated using the height growth models developed here. Similarly, SI conversion equations enable the estimation of the SI for one species based on the SI of another species and environmental variables.

Two novel Pleosporales species isolated from the bark of Acer saccharum.

During a survey of culturable microfungi from the bark of sugar maple (Acer saccharum), Atrocalyx glutinosus and Nigrograna rubescens, two novel species of Pleosporales (Dothideomycetes) were isolated from several locations in eastern Ontario, Canada. Formal species descriptions are presented based on unique colony phenotypes and micromorphological characteristics and supported using multi-locus molecular phylogenetic comparisons with similar species. Both A. glutinosus and N. rubescens produce pycnidial asexual morphs in culture. As their names imply, under specific culture conditions, A. glutinosus excretes large amounts of the glutinous polysaccharide pullulan and N. rubescens produces a dark red naphthoquinone pigment that diffuses in the culture medium. Citation: Mack JN, Sproule A, Shields SW, Seifert KA, Smith M, Overy DP (2024). Two novel Pleosporales species isolated from the bark of Acer saccharum . Fungal Systematics and Evolution 13: 1-14. doi: 10.3114/fuse.2024.13.01.

Designing Effective Low-Impact Developments for a Changing Climate: A HYDRUS-Based Vadose Zone Modeling Approach

Low-Impact Developments (LIDs), like green roofs and bioretention cells, are vital for managing stormwater and reducing pollution. Amidst climate change, assessing both current and future LID systems is crucial. This study utilizes variably saturated flow modeling with the HYDRUS software (version 4.17) to analyze ten locations in Ontario, Canada, focusing on Toronto. Historical and projected climate data are used in flow modeling to assess long-term impacts. Future predicted storms, representing extreme precipitation events, derived from a regional climate model, were also used in the flow modeling. This enabled a comprehensive evaluation of LID performance under an evolving climate. A robust methodology is developed to analyze LID designs, exploring parameters like water inflow volumes, peak intensity, time delays, runoff dynamics, and ponding patterns. The findings indicate potential declines in LID performance attributed to rising water volumes, resulting in notable changes in infiltration for green roofs (100%) and bioretention facilities (50%) compared to historical conditions. Future climate predicted storms indicate reduced peak reductions and shorter time delays for green roofs, posing risks of flooding and erosion. Anticipated extreme precipitation is projected to increase ponding depths in bioretention facilities, resulting in untreated stormwater overflow and prolonged ponding times exceeding baseline conditions by up to 13 h at numerous Ontario locations.

Diversity and potential sources of introduction of the beech leaf nematode (Litylenchus crenatae mccannii) to Ontario, Canada

Litylenchus crenatae mccannii is a foliar nematode that causes severe damage to beech, known as beech leaf disease (BLD). Previous studies have characterized and identified L. crenataein Japan and a subspecies L. crenatae mccannii in the USA. Litylenchus crenatae mccannii has been found to cause BLD in native and non-native beech hosts in North America. As little is known about the distribution and diversity of the nematode in Ontario, Canada, beech foliage was sampled throughout southcentral Ontario. Incidence and severity maps show that BLD spread from its first detections in 2017, in Elgin and Norfolk counties, to the west and northeast. A gradient in severity and incidence was observed with the highest ratings at the locations where it was originally found. The extent of the nematode’s distribution is much broader than BLD, occurring throughout much of the range of American beech. Sequences of two barcoding loci for the L. crenatae mccannii isolates from 11 locations in Ontario showed 100% similarity within and among these locations. The genotype of L. crenatae mccannii found in Ontario is the same as that identified in the USA. This finding is consistent with the fact that 92% of beech imported into Canada is from the USA and suggests that the USA could be the origin of L. crenatae mccannii nematodes in Ontario or that both countries have imported beech trees from the same source country of BLD. This research provides motivation for further studies to clarify the sources of L. crenatae mccannii.

Effect of industrialization on the differences in sources and composition of ambient PM2.5 in two Southern Ontario locations

PM2.5 was sampled over a seven-year period (2013–2019) at two locations ∼50 km apart in Southern Ontario (concurrently for five years: 2015–2019). One is a heavily industrialized site (Hamilton), while the other was a rural site (Simcoe). To assess the impact of industrialization on the composition and sources of PM affecting air quality in these two locations, positive matrix factorization coupled with dispersion normalization (DN-PMF) was used to identify six and eight factors at Simcoe and Hamilton, respectively. The Simcoe factors in order of diminishing PM mass contribution were: particulate sulphate (pSO4), secondary organic aerosol (SOA), crustal matter, particulate nitrate (pNO3), biomass burning, and vehicular emissions. At Hamilton, the effects of industrialization were observed by the ∼36% higher average ambient PM2.5 concentration for the study period as well as the presence of factors unique to metallurgy, i.e., coking and steelmaking, compared to Simcoe. The coking and steelmaking factors contributed ∼15% to the PM mass at Hamilton. Seasonal variants of appropriate nonparametric trend tests with the associated slopes (Sen's) were used to assess statistically significant changes in the factor contributions to PM2.5 over time. Specifically at Hamilton, a significant decline in PM contributions was noted for coking (−0.03 μg/m³/yr or −4.1%/yr) while steelmaking showed no statistically significant decline over the study period. Other factors at Hamilton that showed statistically significant declines over the study period were: pSO4 (−0.27 μg/m³/yr or −12.6%/yr), biomass burning (−0.05 μg/m³/yr or −9.02%/yr), crustal matter (−0.03 μg/m³/yr or −5.28%/yr). These factors mainly accounted for the significant decline in PM2.5 over the study period (−0.35 μg/m³/yr or −4.24%/yr). This work shows the importance of long-term monitoring in assessing the unique contributions and temporal changes of industrialization on air quality in Ontario and similarly affected locations.

Availability of calorie information on online food delivery service platforms among major chain restaurants in Canadian provinces with different calorie labellingpolicies.

This study aimed to characterize the availability of calorie labelling on major online food delivery (OFD) platforms for the largest restaurant brands in Canada to examine differences in provinces with and thosewithout mandatory calorie labelling regulations. Data were collected for the 13 largest restaurant brands with locations in Ontario (with mandatory menu labelling) and Alberta and Quebec (with no mandatory menu labelling) from the web applications of the three largest OFD platforms in Canada. Data were sampled from three selected restaurant locations within each province (n = 117 locations across all provinces) on each platform. Univariate logistic regression models were used to test differences in the presence and amount of calorie labelling and other nutritional information across provinces and platforms. The analytical sample included 48,857 food and beverage items (n = 16,011 in Alberta, n = 16,683 in Ontario, and n = 16,163 in Quebec). Items were more likely to have menu labelling in Ontario (68.7%) than in Alberta (44.4%, OR = 2.75, 95% CI 2.63-2.88) or Quebec (39.1%, OR = 3.42, 95% CI 3.27-3.58). In Ontario, 53.8% of restaurant brands had calorie labelling for > 90% of items, compared to 23.0% in Quebec and 15.4% in Alberta. The presence of calorie labelling also differed across platforms. Nutrition information from OFD services differed across provinces with and thosewithout mandatory calorie labelling. Chain restaurants on OFD service platforms were more likely to provide calorie information in Ontario, where calorie labelling is mandatory, compared to elsewhere where no such policy exists. In all provinces, calorie labelling was inconsistently implemented across OFD service platforms.

An archetypal routing network model to help identify potential charging locations for long-haul electric vehicles in Ontario, Canada

Some estimates show long-haul transport trucks contribute as much as 10% of all Canada’s greenhouse gas emissions. Long-haul electric vehicles (LHEVs) or “electric big rigs” offer a potentially compelling option to mitigate these emissions. However, LHEV charging is expected to burden the power grid significantly more than charging smaller passenger electric vehicles. To date, there is very little research on the impact of charging such vehicles on power grids. The following study leverages conventional long-haul truck GPS data to develop an archetypal routing network (ARN) model that can help identify candidate charging infrastructure locations in Ontario, Canada. Results suggest that based on historical LHEV travel patterns, most candidate charging station locations fall along critical road links in Ontario like Highway 401 and Highway 400. Subsequently, the additional electricity demand of these stations is estimated and compared with Ontario’s current electricity demand. Though the charging stations’ aggregate daily demand is smaller than Ontario’s overall demand, some of these stations’ hourly electricity demand during peak hours are great enough to put significant pressure on local infrastructures.

Moving towards a continuum of safer supply options for people who use drugs: A qualitative study exploring national perspectives on safer supply among professional stakeholders in Canada

BackgroundNovel public health interventions are needed to address the toxic drug supply and meet the needs of people who use drugs amidst the overdose crisis. Safer supply – low-barrier distribution of pharmaceutical grade substances – has been implemented in some jurisdictions to provide safer alternatives to the unregulated drug supply, yet no studies to date have explored professional stakeholder perspectives on this approach.MethodsWe used purposive sampling to recruit professional stakeholders (n = 17) from four locations in British Columbia, Ontario, and Nova Scotia, including program managers, executive directors, political and health authority representatives, and healthcare providers involved in the design, implementation, and/or operation of safer supply programs in their communities. Semi-structured, one-to-one interviews were conducted, and interview data were coded and analyzed using thematic analyses.ResultsParticipants defined safer supply as low-barrier access to substances of known quality and quantity, offered on a continuum from prescribed to a legal, regulated supply, and focused on upholding autonomy and liberation of people who use drugs. Stakeholders expressed support for safer supply but explained that current iterations do not meet the needs of all people who use drugs and that implementation is limited by a lack of willing prescribers, stigma towards people who use drugs, and precarity of harm reduction programs to political ideology. Stakeholders expressed strong support for wider-reaching approaches such as decriminalization, legalization, and regulation of substances as a way to fully realize a continuum of safer supply, directly address the overdose crisis and toxic drug supply, and ensure equity of access nationally.ConclusionThe results of this study highlight the need for innovative strategies to address the overdose crisis and that safer supply has the potential to benefit certain people who use drugs. A one-size-fits-all approach is not sufficient and the perspectives of professional stakeholders should be considered alongside those of people who use drugs when designing and implementing future safer supply.

Predicting physical and geomorphic habitat associated with historical lake whitefish and cisco spawning locations in Lakes Erie and Ontario

The Great Lakes basin was historically populated by multiple, coevolved coregonine species, but much of that diversity has been lost. In Lakes Erie and Ontario, both lake whitefish (Coregonus clupeaformis) and cisco (Coregonus artedi) occurred in high numbers before habitat degradation, overfishing, invasive species, and other factors caused significant declines. There is growing interest in restoring these populations, and suggested actions include restoration of critical habitats such as spawning habitat. Unfortunately, our current understanding of lake whitefish and cisco spawning habitat characteristics and locations in these lakes is limited. To highlight areas of potential importance for conservation and restoration, we used random forest models and data on historical spawning locations to predict lake whitefish and cisco spawning habitats based on hypothesized key factors including wind fetch, ice cover duration, distance from 1st and 6th order tributaries, and lake bottom substrate. Our model accurately predicted spawning habitat locations for 71% and 54% of cases for lake whitefish and cisco, respectively. Fetch was the most important variable in the lake whitefish model, with spawning habitats being most likely to occur in regions of low to moderate fetch. Cisco spawning habitats were most likely to occur in areas of relatively low fetch near a 1st order stream. We used these models to predict spawning habitat locations for both species across Lakes Erie, Ontario, and St. Clair. Our results improve our understanding of lake whitefish and cisco spawning habitat characteristics and will aid in the spatial prioritization of actions to restore these native fishes.

Accessibility of Canadian COVID-19 Testing Locations for People with Disabilities During the Third Wave of the COVID-19 Pandemic

Background: Canadians with disabilities make up nearly a quarter of the population yet faced barriers in accessing information about COVID-19 testing accessibility across the country. Objective: This study aimed to understand the availability of accessibility information for COVID-19 testing sites in Canada. To date, no known studies have evaluated the availability of accessibility information online.Methods: An environmental scan of COVID-19 testing websites was conducted (1) nationally through the provincial/territorial websites for COVID-19 testing and (2) in Ontario, where there was individual location information. Data on key accessibility features were extracted from the website to simulate the user experience of booking a COVID-19 test during March 2021. Results: All provinces and territories provided minimal accessibility information on their provincial or territorial COVID-19 testing websites. Only Ontario included accessibility information for individual testing locations. Out of 170 individual testing locations in Ontario, few had information about accessibility, with only 8.2% listing at least 3 of the 5 key accessibility features measured on their websites.Conclusions: This study demonstrates that, more than a year into the pandemic, there existed a clear lack of accessibility information for testing locations for Canadians with disabilities.

Practice Patterns of Palmoplantar Pustulosis: Patient Demographics and Treatment Options.

Palmoplantar pustulosis (PPP) is a chronic skin condition characterized by sterile pustules on the palms and soles. This condition is more commonly reported among women and smokers causing considerable discomfort and interference with daily activities. Although there are various off-label treatment options available for PPP, there remains a demand to identify more effective and safer treatments. To review the patient demographics and treatment patterns of our PPP patient population. A retrospective chart review was performed at a dermatology office with two locations in Ontario, Canada. We identified 71 adult PPP patients. A third of patients did not return for follow up after diagnosis. Among those who returned for follow-up, 20% were managed with topical therapy alone. Of our patients who took systemic treatment for PPP, apremilast, followed by ustekinumab and guselkumab, had the greatest retention of therapy. Targeting PDE4, IL-12/23 and IL-23 provided some benefit for our patients with PPP leading to greatest retention of therapy over time. Further investigation is required into the cause for high no-show rates and the search for effective and safe treatment options.

Genome-Wide Association Study of Soybean Germplasm Derived From Canadian × Chinese Crosses to Mine for Novel Alleles to Improve Seed Yield and Seed Quality Traits.

Genome-wide association study (GWAS) has emerged in the past decade as a viable tool for identifying beneficial alleles from a genomic diversity panel. In an ongoing effort to improve soybean [Glycine max (L.) Merr.], which is the third largest field crop in Canada, a GWAS was conducted to identify novel alleles underlying seed yield and seed quality and agronomic traits. The genomic panel consisted of 200 genotypes including lines derived from several generations of bi-parental crosses between modern Canadian × Chinese cultivars (CD-CH). The genomic diversity panel was field evaluated at two field locations in Ontario in 2019 and 2020. Genotyping-by-sequencing (GBS) was conducted and yielded almost 32 K high-quality SNPs. GWAS was conducted using Fixed and random model Circulating Probability Unification (FarmCPU) model on the following traits: seed yield, seed protein concentration, seed oil concentration, plant height, 100 seed weight, days to maturity, and lodging score that allowed to identify five QTL regions controlling seed yield and seed oil and protein content. A candidate gene search identified a putative gene for each of the three traits. The results of this GWAS study provide insight into potentially valuable genetic resources residing in Chinese modern cultivars that breeders may use to further improve soybean seed yield and seed quality traits.

Genetic analysis of sucrose concentration in soybean seeds using a historical soybean genomic panel.

Significant QTL for sucrose concentration have been identified using a historical soybean genomic panel, which could aid in the development of food-grade soybean cultivars. Soybean (Glycine max (L.) Merr) is a crop of global importance for both human and animal consumption, which was domesticated in China more than 6000years ago. A concern about losing genetic diversity as a result of decades of breeding has been expressed by soybean researchers. In order to develop new cultivars, it is critical for breeders to understand the genetic variability present for traits of interest in their program germplasm. Sucrose concentration is becoming an increasingly important trait for the production of soy-food products. The objective of this study was to use a genome-wide association study (GWAS) to identify putative QTL for sucrose concentration in soybean seed. A GWAS panel consisting of 266 historic and current soybean accessions was genotyped with 76k genotype-by-sequencing (GBS) SNP data and phenotyped in four field locations in Ontario (Canada) from 2015 to 2017. Seven putative QTL were identified on chromosomes 1, 6, 8, 9, 10, 13 and 14. A key gene related to sucrose synthase (Glyma.06g182700) was found to be associated with the QTL located on chromosome 6. This information will facilitate efforts to increase the available genetic variability for sucrose concentration in soybean breeding programs and develop new and improved high-sucrose soybean cultivars suitable for the soy-food industry.

Autonomous recordings suggest contrasting patterns in Prairie Warbler (Setophaga discolor) vocal activity between coastal and inland locations in Ontario, Canada

To inform the design of targeted, species-specific surveys of Prairie Warbler (Setophaga discolor) in Ontario, Canada, we used autonomous recording units (ARUs) to document patterns in male vocal activity. We deployed recorders within the territories of breeding males at coastal sites near Georgian Bay, and at inland sites near Kaladar, in June 2015 and 2016, respectively. Although coastal and inland sites are <250 km apart, we observed distinct differences in the patterns and frequency of male singing. Overall, the mean number of songs per minute of males at inland sites near Kaladar was nearly triple that of coastal sites near Georgian Bay. Daily singing activity peaked shortly after sunrise and declined throughout the day at both sites. Daily singing activity was uniformly high across the entire morning period at coastal sites, whereas at inland sites the highest rates of singing were during the post-dawn morning period. Singing activity varied by chronological day at inland sites, with distinct peaks at the beginning and end of June. Singing at coastal sites did not vary by chronological day and was consistently low throughout June. Although our sample sizes are small, with minimal replication, we discuss our results in the context of reduced pairing success and male-biased sex ratios in small, isolated populations. In addition to documenting singing activity patterns to optimize future surveys for species of conservation concern, ARUs may also signal potential demographic differences important for population persistence that warrant further exploration.

Evaluation of barley testing locations in Ontario

To develop new barley cultivars, promising genotypes are evaluated for their performance each year at several test locations representing the target region. In this study, we analyzed the Ontario barley registration trial data from 2015 to 2020 to understand the barley mega-environment in Ontario and to evaluate the suitability of the test locations. The analysis showed that the barley test locations fall into two mega-environments, with a major mega-environment consists of five test locations and a minor mega-environment with a single test location. Among the six test locations used for the barley registration trials, Palmerston was found to be the most desirable for the barley cultivar evaluation representing the Ontario barley growing region. This study also identified OB2930-35, a recently released cultivar, to be both high yielding and stable across Ontario. These findings are useful for future barley breeding and cultivar evaluation in Ontario.

Optimization and validation of a cost-effective protocol for biosurveillance of invasive alien species.

Environmental DNA (eDNA) metabarcoding has revolutionized biodiversity monitoring and invasive pest biosurveillance programs. The introduction of insect pests considered invasive alien species (IAS) into a non‐native range poses a threat to native plant health. The early detection of IAS can allow for prompt actions by regulating authorities, thereby mitigating their impacts. In the present study, we optimized and validated a fast and cost‐effective eDNA metabarcoding protocol for biosurveillance of IAS and characterization of insect and microorganism diversity. Forty‐eight traps were placed, following the CFIA's annual forest insect trapping survey, at four locations in southern Ontario that are high risk for forest IAS. We collected insects and eDNA samples using Lindgren funnel traps that contained a saturated salt (NaCl) solution in the collection jar. Using cytochrome c oxidase I (COI) as a molecular marker, a modified Illumina protocol effectively identified 2,535 Barcode Index Numbers (BINs). BINs were distributed among 57 Orders and 304 Families, with the vast majority being arthropods. Two IAS (Agrilus planipennis and Lymantria dispar) are regulated by the Canadian Food Inspection Agency (CFIA) as plant health pests, are known to occur in the study area, and were identified through eDNA in collected traps. Similarly, using 16S ribosomal RNA and nuclear ribosomal internal transcribed spacer (ITS), five bacterial and three fungal genera, which contain species of regulatory concern across several Canadian jurisdictions, were recovered from all sampling locations. Our study results reaffirm the effectiveness and importance of integrating eDNA metabarcoding as part of identification protocols in biosurveillance programs.

Juice attributes of Ontario-grown culinary (dessert) apples for cider

Continued interest in the commercial production of cider in Ontario has revealed that there is a lack of information available to apple producers and cidermakers on the juice attributes of culinary dessert apple for making cider and how they may vary from orchard to orchard. A two-year study was conducted to characterize the juice characteristics of 18 common culinary dessert apple cultivars grown at several locations in Ontario. Juice was assayed for soluble solids concentration, pH, titratable acidity (TA), juice extraction efficiency, yeast assimilable nitrogen (YAN), polyphenols, and soluble solids to TA ratio. Significant differences among cultivars were observed for all parameters, which varied by orchard and year, except juice extraction efficiency. These data underly the importance of assaying juice every growing season prior to fermentation. Cidermakers should focus on juice characteristics from culinary apples that are more difficult to alter (with amendments), and use juice with lower pH, higher TA and polyphenols, and moderate to higher YAN to optimize cider quality and flavour. Overall, this study will inform cidermakers of which culinary apple cultivars might be preferable for fermentation as well as how they might be blended to optimize cider quality. Notwithstanding annual and orchard variation, cultivars that meet these criteria include Cortland, Crimson Crisp, Honeycrisp, Jonagold, McIntosh, and Northern Spy. If making cider from Ambrosia, Crispin, Empire, Fuji, Gala, Golden Delicious, or Idared, cidermakers should expect to blend the juice from these cultivars to create a more fully balanced juice prior to fermentation.

Enhancing In-crop Diversity in Common Bean by Planting Cultivar Mixtures and Its Effect on Productivity

Common bean (Phaseolus vulgaris L.) is the most important food legume crop worldwide. Canadian beans, especially large seeded cultivars of Andean origin, have relatively narrow genetic diversities. Establishing crops with mixtures of cultivars instead of pure lines is a simple, cost effective way to increase genetic diversity in the field. A number of studies have demonstrated the benefits of mixture cropping over monocropping in controlling disease, increasing water use efficiency and increasing yield stability. The objective of this study was to determine the effects of increasing in-field diversity, by using mixtures of bean cultivars instead of monocultures, on productivity. The feasibility of growing bean cultivar mixtures in southern Ontario environments was confirmed with a small pilot study that was conducted with four bean cultivars and restricted number of mixtures at two locations in 2017. Mixture performance experiments were performed with seven diverse bean genotypes at two Ontario locations [Woodstock and Elora (two planting dates) research stations] as pure stands and all possible binary mixtures (planted in alternate rows or as completely random mixtures) in 2018. Conventional plot-based above ground crop data were collected. Mixing efficiencies were calculated from the yield data using a Relative yield of the mixture (RYM) index. Diallel analysis was used to identify general mixing ability of cultivars and specific mixing abilities of mixtures. Significant differences among seven bean cultivars and their mixtures were identified in all three environments for all analyzed traits. The results indicated multiple benefits of planting mixtures compared to monocultures A number of mixtures overyielded component cultivars grown in pure stands; they had higher yields, RYM index values greater than one and positive specific mixing abilities (for yield) in both types of biblends. The research has the potential to provide a theoretical basis for the use of precision agriculture tools to plant fields with mixtures instead of monocultures. It could lead to greater in-field diversity in the crop and in the above and below ground ecosystems that might provide greater buffering capacity and resiliency to the cropping system as well as increased ecosystem services.

Study protocol for a hospital-to-home transitional care intervention for older adults with multiple chronic conditions and depressive symptoms: a pragmatic effectiveness-implementation trial

BackgroundOlder adults (> 65 years) with multiple chronic conditions (MCC) and depressive symptoms experience frequent transitions between hospital and home. Care transitions for this population are often poorly coordinated and fragmented, resulting in increased readmission rates, adverse medical events, decreased patient satisfaction and safety, and increased caregiver burden. There is a dearth of evidence on best practices in the provision of transitional care for older adults with MCC and depressive symptoms transitioning from hospital-to-home. This paper presents a protocol for a two-armed, multi-site pragmatic effectiveness-implementation trial of Community Assets Supporting Transitions (CAST), an evidence-informed nurse-led six-month intervention that supports older adults with MCC and depressive symptoms transitioning from hospital-to-home. The Collaborative Intervention Planning Framework is being used to engage patients and other key stakeholders in the implementation and evaluation of the intervention and planning for intervention scale-up to other communities.MethodsParticipants will be considered eligible if they are > 65 years, planned for discharged from hospital to the community in three Ontario locations, self-report at least two chronic conditions, and screen positive for depressive symptoms. A total of 216 eligible and consenting participants will be randomly assigned to the control (usual care) or intervention (CAST) arm. The intervention consists of tailored care delivery comprising in-home visits, telephone follow-up and system navigation support. The primary measure of effectiveness is mental health functioning of the older adult participant. Secondary outcomes include changes in physical functioning, depressive symptoms, anxiety, perceived social support, patient experience, and health and social service use and cost, from baseline to 6- and 12-months. Caregivers will be assessed for caregiver strain, depressive symptoms, anxiety, health-related quality of life, and health and social service use and costs. Descriptive and qualitative data from older adult and caregiver participants, and the nurse interventionists will be used to examine implementation of the intervention, how the intervention is adapted within each study region, and its potential for sustainability and scalability to other jurisdictions.DiscussionA nurse-led transitional care strategy may provide a feasible and effective means for improving health outcomes and patient/caregiver experience and reduce service use and costs in this vulnerable population.Trial registration# NCT03157999.Registration Date: April 4, 2017.

The first record of protoporphyrinogen oxidase and four-way herbicide resistance in eastern Canada

This is the first record of protoporphyrinogen oxidase (PPO) inhibitor resistance in eastern Canada, and the second record of a glyphosate-resistant weed in Quebec. In 2016 and 2017, waterhemp seed was collected from 25 locations across Ontario and Quebec. All populations tested positive for imazethapyr resistance. Three-way resistance to imazethapyr, atrazine, and glyphosate was confirmed in 80% of the samples. Additionally, between 2015 and 2017, waterhemp seed was collected from 74 locations in Ontario or Quebec and resistance to lactofen was confirmed in 28% of the seed lots screened.