Waterloo Research
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Item This is a test submission(Springer, 2024) Carmini, PriscillaLorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborumItem Current Research on Gaseous Ammonia Detecting and Capture Technologies(Elsevier, 2023-10-27) Akhand, Aamer; Wu, Xiao-YuAmmonia is currently widely used for fertilizers, and it continues to grow as a potential clean fuel source or hydrogen carrier, which may result in growing trace amounts in the atmosphere. Increasing anthropogenic ammonia emissions raises concerns such as disrupting the global nitrogen cycle and negating the greenhouse gas reduction. This review article outlines and compiles recent studies on gaseous ammonia sensing and absorption/adsorption, which could alert or reduce rogue emissions, i.e., unintended anthropogenic releases of ammonia. Different sensors and their characteristics are outlined with a focus on the more popular chemoresistive technologies. Several absorption/adsorption methods from metal-organic frameworks (MOFs) and deep eutectic solvents (DESs) are described and highlighted.Item Validated Dynamic Stall Simulation of Pitching Low Reynolds Number Airfoils(American Institute of Aeronautics and Astronautics, 2024-08) Zilstra, Alison; Johnson, David A.Deep dynamic stall is one of several complex behaviors that result in extreme variation of the aerodynamic loads on small wind turbine (SWT) blades during unsteady wind conditions. In this study, unsteady Reynolds-averaged Navier–Stokes simulations are performed for two low Reynolds number (Re) airfoils where sinusoidal pitching is applied to replicate the dynamic stall that occurs on rotating SWT blades. The SD 7037 airfoil is simulated at Re=4.1x10⁴ and a pitching reduced frequency of k=0.08, and the S833 airfoil is at Re=1.7x10⁵ and k=0.06. The simulated lift coefficient and dynamic stall timing agree with experimental data, which is attributed to the wall-normal resolution of the mesh and is an advancement from the early prediction of stall seen consistently in previous numerical studies. The accurate prediction of dynamic stall is found to be dependent on the correct simulation of the bursting of the laminar separation bubble (LSB), which initiates the complete separation of the boundary layer and the formation of a leading-edge vortex. The γ-Reθ,t k-⍵ model combined with the use of a fine mesh at the airfoil leading edge results in an accurate simulation of the bursting LSB and the correct prediction of the deep dynamic stall.Item The current state of integrating equity, diversity and inclusion into knowledge mobilization: a systematic literature review(Emerald Publishing, 2024-08-15) Cornelius-Hernandez, Tracelyn; Clarke, AmeliaPurpose – The purpose of this paper is to systematically review and analyze the academic literature on integrating equity, diversity, and inclusion (EDI) into knowledge mobilization (KMb). Design/methodology/approach – This systematic literature review of the body of scholarly literature published on integrating EDI with KMb follows established methods and protocols proposed by Popay et al. (2006) and Page et al. (2021). Using a relevant keyword string, a search was conducted in ProQuest and SCOPUS to find peer-reviewed articles, which were then screened using predetermined inclusion and exclusion criteria. Finally, inductive and deductive analyses were conducted on the selected articles. Findings – The findings suggest that most of the authors are based in the Global North, the majority of literature was published in the last two years, and that it is conceptual. This synthesis highlights five solution-oriented themes: acknowledging inherent bias, centering marginalized groups, promoting responsible knowledge mobilization, establishing partnerships, and advocating for transformational and systemic change. This study also identifies four broad barriers: inherent, unconscious, and implicit biases, a lack of evidence-based best practices, siloing of research and information, and a lack of institutional support and resources. Findings also highlight the value of further research into barriers, gaps and opportunities. Originality/value – By studying the intersection of EDI and KMb, this contemporary synthesis of the state of the field presents opportunities for future research into gaps, barriers and potential solutions.Item Never Skip Leg Day Again: Training the Lower Body with Vertical Jumps in a Virtual Reality Exergame(Association for Computing Machinery, 2023-04-23) Cmentowski, Sebastian; Karaosmanoglu, Sukran; Nacke, Lennart E.; Steinicke, Frank; Krüger, JensVirtual Reality (VR) exergames can increase engagement in and motivation for physical activities. Most VR exergames focus on the upper body because many VR setups only track the users’ heads and hands. To become a serious alternative to existing exercise programs, VR exergames must provide a balanced workout and train the lower limbs, too. To address this issue, we built a VR exergame focused on vertical jump training to explore full-body exercise applications. To create a safe and effective training, nine domain experts participated in our prototype design. Our mixed-methods study confirms that the jump-centered exercises provided a worthy challenge and positive player experience, indicating long-term retention. Based on our findings, we present five design implications to guide future work: avoid an unintended forward drift, consider technical constraints, address safety concerns in full-body VR exergames, incorporate rhythmic elements with fluent movement patterns, adapt difficulty to players’ fitness progression status.Item Born to Run, Programmed to Play: Mapping the Extended Reality Exergames Landscape(Association for Computing Machinery, 2024-05-11) Karaosmanoglu, Sukran; Cmentowski, Sebastian; Nacke, Lennart E.; Steinicke, FrankMany people struggle to exercise regularly, raising the risk of serious health-related issues. Extended reality (XR) exergames address these hurdles by combining physical exercises with enjoyable, immersive gameplay. While a growing body of research explores XR exergames, no previous review has structured this rapidly expanding research landscape. We conducted a scoping review of the current state of XR exergame research to (i) provide a structured overview, (ii) highlight trends, and (iii) uncover knowledge gaps. After identifying 1318 papers in human-computer interaction and medical databases, we ultimately included 186 papers in our analysis. We provide a quantitative and qualitative summary of XR exergame research, showing current trends and potential future considerations. Finally, we provide a taxonomy of XR exergames to help future design and methodological investigation and reporting.Item Robust-stochastic models for profit maximizing hub location problems(INFORMS, 2021) Taherkhani, Gita; Alumur, Sibel A.; Hosseini, MojtabaThis paper introduces robust-stochastic models for profit maximizing capacitated hub location problems in which two different types of uncertainty including stochastic demand and uncertain revenue are simultaneously incorporated into the problem. First, a two-stage stochastic program is presented where demand and revenue are jointly stochastic. Next, robust-stochastic models are developed to better model uncertainty in the revenue while keeping the demand stochastic. Two particular cases are studied based on the dependency between demand and revenue. In the first case, a robust-stochastic model with a min-max regret objective is developed assuming a finite set of scenarios that describe uncertainty associated with the revenue under a revenue-elastic demand setting. For the case when demand and revenue are independent, robust-stochastic models with a max-min criterion and a min-max regret objective are formulated considering both interval uncertainty and discrete scenarios, respectively. It is proved that the robust-stochastic version with max-min criterion can be viewed as a special case of the min-max regret stochastic model. Exact algorithms based on Benders decomposition coupled with sample average approximation scheme are proposed. Exploiting the repetitive nature of sample average approximation, generic acceleration methodologies are developed to enhance the performance of the algorithms enabling them to solve large-scale intractable instances. Extensive computational experiments are performed to consider the efficiency of the proposed algorithms and also to analyze the effects of uncertainty under different settings. The qualities of the solutions obtained from different modeling approaches are compared under various parameter settings. Computational results justify the need to solve robust-stochastic models to embed uncertainty in decision making to design resilient hub networks.Item An alternative approach to address uncertainty in hub location(Springer, 2023) Janschekowitz, Marc; Taherkhani, Gita; Alumur, Sibel A.; Nickel, StefanIn this paper, optimization and simulation techniques are integrated to address single and multiple allocation hub network design problems under uncertainty. Using a scenario-based iterative optimization-simulation approach four sources of uncertainty are considered: the demand to be transported within the network, the associated transportation costs as well as the fixed costs for both opening hub facilities and establishing the connections between them. Additionally, flow-dependent economies of scale on all network connections are incorporated in the simulation phase. A value of simulation measure is introduced to evaluate the performance of the methodology. The computational tests conducted on the well-known CAB data set with varying levels of uncertainty show that the approach can result in better solutions with up to 6.6% lower cost compared to its deterministic counterpart.Item Observations of submesoscale eddy-driven heat transport at an ice shelf calving front(Springer Nature, 2022-06-22) Friedrichs, Drew M.; McInerney, Jasmin B. T.; Oldroyd, Holly J.; Lee, Won Sang; Yun, Sukyoung; Yoon, Seung-Tae; Stevens, Craig L.; Zappa, Christopher J.; Dow, Christine F.; Mueller, Derek; Steiner, Oscar Sepulveda; Forrest, Alexander L.Antarctica’s ice shelves buttress the continent’s terrestrial ice, helping slow the loss of grounded ice into the ocean and limiting sea level rise. Ice-ocean interaction plays a critical role in ice shelf stability by driving basal melt rates. Consequently, improved prediction of the future state of ice shelves lies in understanding the coastal ocean mechanics that deliver heat to their cavities. Here, we present autonomous glider-based observations of a coherent structure at the calving front of a cold-water cavity ice shelf (Nansen Ice Shelf, East Antarctica). This ~10 km-wide eddy dominated the local ocean circulation in the austral summer of 2018/2019, promoting an upwelling of cold ice shelf water and a deepening of warm surface water. Microstructure turbulence measurements show a resulting maximum vertical heat transport of 10 W m−2 at depths equivalent to the ice shelf draft. Similar eddy-driven heat transport further into the ice shelf cavity would support enhanced summertime melt in regions of shallower ice draft.Item Modeling the Deformation Regime of Thwaites Glacier, West Antarctica, Using a Simple Flow Reaction for Ice Anisotropy (ESTAR)(Wiley; American Geophysical Union (AGU), 2022-02-21) McCormack, Felicity S.; Warner, Roland C.; Seroussi, Helene; Dow, Christine F.; Roberts, Jason L.; Treverrow, Adamce deformation dominates the evolution of ice shelf flow and the slow-moving regions in the interior of ice sheets. However, deformation may be poorly represented in large-scale ice sheet models that use the Glen flow relation, due to its questionable applicability to the steady-state flow of anisotropic ice that prevails in ice sheets, having been derived from secondary creep rates of isotropic ice. We assess the deformation regimes of Thwaites Glacier, West Antarctica, using the Glen and “Empirical Scalar Tertiary Anisotropy Regime”, (ESTAR) flow relations, the latter being derived from steady-state deformation rates of anisotropic ice. For grounded ice, the character of the flow relation determines the contribution of deformation to overall flow, with ESTAR producing greater bed-parallel shear deformation than the standard Glen flow relation. The ESTAR experiments show larger basal shear stress maxima than the standard Glen experiment because ESTAR treats the responses to simple shear stresses and compression stresses differently, reducing the role of lateral and longitudinal stresses in momentum balance. On the Thwaites Glacier Tongue, ESTAR provides the best match to observed speeds by accounting for the differing effects of stresses on ice flow. Our results highlight the importance of the numerical description of anisotropy, particularly: In regions of transition from deformation-dominated to sliding-dominated flow; in the approach to the grounding line, and across ice shelves. Given the importance of these locations in determining mass flux into the ocean, our results have implications for projections of sea level change from Antarctic ice loss.Item Basal channels drive active surface hydrology and transverse ice shelf fracture(Science, 2018-06-13) Dow, Christine F.; Lee, Won Sang; Greenbaum, Jamin S.; Greene, Chad A.; Blankenship, Donald D.; Poinar, Kristin; Forrest, Alexander L.; Young, Duncan A.; Zappa, Christopher J.Ice shelves control sea-level rise through frictional resistance, which slows the seaward flow of grounded glacial ice. Evidence from around Antarctica indicates that ice shelves are thinning and weakening, primarily driven by warm ocean water entering into the shelf cavities. We have identified a mechanism for ice shelf destabilization where basal channels underneath the shelves cause ice thinning that drives fracture perpendicular to flow. These channels also result in ice surface deformation, which diverts supraglacial rivers into the transverse fractures. We report direct evidence that a major 2016 calving event at Nansen Ice Shelf in the Ross Sea was the result of fracture driven by such channelized thinning and demonstrate that similar basal channel-driven transverse fractures occur elsewhere in Greenland and Antarctica. In the event of increased basal and surface melt resulting from rising ocean and air temperatures, ice shelves will become increasingly vulnerable to these tandem effects of basal channel destabilitization.Item Seismic evidence for complex sedimentary control of Greenland Ice Sheet flow(Science, 2021-08-16) Kulessa, Bernd; Hubbard, Alun L.; Booth, Adam D.; Bougamont, Marion; Dow, Christine F.; Doyle, Samuel H.; Christoffersen, Poul; Lindback, Katrin; Pettersson, Rickard; Fitzpatrick, Andrew A. W.; Jones, Glenn A.The land-terminating margin of the Greenland Ice Sheet has slowed down in recent decades, although the causes and implications for future ice flow are unclear. Explained originally by a self-regulating mechanism where basal slip reduces as drainage evolves from low to high efficiency, recent numerical modeling invokes a sedimentary control of ice sheet flow as an alternative hypothesis. Although both hypotheses can explain the recent slowdown, their respective forecasts of a long-term deceleration versus an acceleration of ice flow are contradictory. We present amplitude-versus-angle seismic data as the first observational test of the alternative hypothesis. We document transient modifications of basal sediment strengths by rapid subglacial drainages of supraglacial lakes, the primary current control on summer ice sheet flow according to our numerical model. Our observations agree with simulations of initial postdrainage sediment weakening and ice flow accelerations, and subsequent sediment restrengthening and ice flow decelerations, and thus confirm the alternative hypothesis. Although simulated melt season acceleration of ice flow due to weakening of subglacial sediments does not currently outweigh winter slowdown forced by self-regulation, they could dominate over the longer term. Subglacial sediments beneath the Greenland Ice Sheet must therefore be mapped and characterized, and a sedimentary control of ice flow must be evaluated against competing self-regulation mechanisms.Item Characterizing subglacial hydrology within the Amery Ice Shelf catchment using numerical modeling and satellite altimetry(Wiley, 2024-04-20) Wearing, Martin G.; Dow, Christine F.; Goldberg, Daniel N.; Gourmelen, Noel; Hogg, Anna E.; Jakob, LiviaMeltwater forms at the base of the Antarctic Ice Sheet due to geothermal heat flux (GHF) and basal frictional dissipation. Despite the relatively small volume, this water has a profound effect on ice-sheet dynamics. However, subglacial melting and hydrology in Antarctica remain highly uncertain, limiting our ability to assess their impact on ice-sheet dynamics. Here we examine subglacial hydrology within the Amery Ice Shelf catchment, East Antarctica, using the subglacial hydrology model GlaDS. We calculate subglacial melt rates using a higher-order ice-flow model and two GHF estimates. We find a catchment-wide melt rate of 7.03 Gt year−1 (standard deviation = 1.94 Gt year−1), which is ≥50% greater than previous estimates. The contribution from basal dissipation is approximately 40% of that from GHF. However, beneath fast-flowing ice streams, basal dissipation is an order of magnitude larger than GHF, leading to a significant increase in channelized subglacial flux upstream of the grounding line. We validate GlaDS using high-resolution interferometric-swath radar altimetry, with which we detect active subglacial lakes and fine-scale ice-shelf basal melting. We find a network of subglacial channels that connects areas of deep subglacial water coincident with active subglacial lakes, and channelized discharge at the grounding line coinciding with enhanced ice-shelf basal melting. The concentrated discharge of meltwater provides 36% of the freshwater released into the ice-shelf cavity, in addition to ice-shelf basal melting. This suggests that ice-shelf basal melting is strongly influenced by subglacial hydrology and could be affected by future changes in subglacial discharge, such as lake drainage or channel rerouting.Item Subglacial discharge accelerates future retreat of Denman and Scott Glaciers, East Antarctica(American Association for the Advancement of Science, 2023-10-27) Pelle, Tyler; Greenbaum, Jamin S.; Dow, Christine F.; Jenkins, Adrian; Morlighem, MathieuIce shelf basal melting is the primary mechanism driving mass loss from the Antarctic Ice Sheet, yet it is unknown how the localized melt enhancement from subglacial discharge will affect future Antarctic glacial retreat. We develop a parameterization of ice shelf basal melt that accounts for both ocean and subglacial discharge forcing and apply it in future projections of Denman and Scott Glaciers, East Antarctica, through 2300. In forward simulations, subglacial discharge accelerates the onset of retreat of these systems into the deepest continental trench on Earth by 25 years. During this retreat, Denman Glacier alone contributes 0.33 millimeters per year to global sea level rise, comparable to half of the contemporary sea level contribution of the entire Antarctic Ice Sheet. Our results stress the importance of resolving complex interactions between the ice, ocean, and subglacial environments in future Antarctic Ice Sheet projections.Item Radarsat constellation mission derived winter glacier velocities for the St. Elias Icefield, Yukon/Alaska: 2022 and 2023(Taylor & Francis, 2023-10-10) Van Wychen, W.; Bayer, Courtney; Copland, Luke; Brummel, Erika; Dow, ChristineHere we use high resolution (5 m) Radarsat Constellation Mission (RCM) imagery acquired in winters 2022 and 2023 to determine motion across glaciers of the St. Elias Icefield in Yukon/Alaska. Our regional velocity mapping largely conforms with previous studies, with faster motion (>600 m/yr) for the glaciers originating in the Yukon that drain southward and westward to the coast of Alaska and relatively slower motion (100–400 m/yr) for the land terminating glaciers that drain eastward and northeastward and stay within the Yukon. We also identify two new glacier surges within the icefields: the surge of Nàłùdäy (Lowell) Glacier in Winter 2022, and Chitina Glacier in Winter 2023, and track the progression of each surge from January to March utilizing ∼4-day repeat RCM imagery. To evaluate the quality of RCM-derived velocities, we compare our results with 50 simultaneous measurements at three on-ice dGPS stations located on two Yukon glaciers and find the average absolute difference between measurements to be 6.6 m/yr. Our results demonstrate the utility of RCM data to determine glacier motion across large regions with complex topography, to support process-based studies of fast flowing and surge-type glaciers and continue the legacy of velocity products derived from the Radarsat-2 mission.Item Migration of the shear margins at Thwaites Glacier: Dependence on basal conditions and testablities against field data.(AGU, 2023-03-07) Summers, Paul T.; Elsworth, Cooper W.; Dow, Christine F.; Suckale, JennyProjections of global sea level depend sensitively on whether Thwaites Glacier, Antarctica, will continue to lose ice rapidly. Prior studies have focused primarily on understanding the evolution of ice velocity and whether the reverse-sloping bed at Thwaites Glacier could drive irreversible retreat. However, the overall ice flux to the ocean and the possibility of irreversible retreat depend not only on the ice speed but also on the width of the main ice trunk. Here, we complement prior work by focusing specifically on understanding whether the lateral boundaries of the main ice trunk, termed shear margins, might migrate over time. We hypothesize that the shear margins at Thwaites Glacier will migrate on a decadal timescale in response to continued ice thinning and surface steepening. We test this hypothesis by developing a depth-averaged, thermomechanical free-boundary model that captures the complex topography underneath the glacier and solves for both the ice velocity and for the position of the shear margins. We find that both shear margins are prone to migration in response to ice thinning with basal strength and surface slope steepening determining their relative motion. We construct four end-member cases of basal strength that represent different physical properties governing friction at the glacier bed and present two cases of ice thinning to contrast the effects of surface steepening and ice thinning. We test our model by hindcasting historic data and discuss how data from ongoing field campaigns could further be used to test our model.Item A multi-resolution approach to point cloud registration without control points(MDPI, 2023-02-20) Bash, Eleanor A.; Wecker, Lakin; Rahman, Mir Mustafizur; Dow, Christine F.; McDermid, Greg; Samavati, Faramarz F.; Whitehead, Ken; Moorman, Brian J.; Medrzycka, Dorota; Copland, LukeTerrestrial photographic imagery combined with structure-from-motion (SfM) provides a relatively easy-to-implement method for monitoring environmental systems, even in remote and rough terrain. However, the collection of in-situ positioning data and the identification of control points required for georeferencing in SfM processing is the primary roadblock to using SfM in difficult-to-access locations; it is also the primary bottleneck for using SfM in a time series. We describe a novel, computationally efficient, and semi-automated approach for georeferencing unreferenced point clouds (UPC) derived from terrestrial overlapping photos to a reference dataset (e.g., DEM or aerial point cloud; hereafter RPC) in order to address this problem. The approach utilizes a Discrete Global Grid System (DGGS), which allows us to capitalize on easily collected rough information about camera deployment to coarsely register the UPC using the RPC. The DGGS also provides a hierarchical set of grids which supports a hierarchical modified iterative closest point algorithm with natural correspondence between the UPC and RPC. The approach requires minimal interaction in a user-friendly interface, while allowing for user adjustment of parameters and inspection of results. We illustrate the approach with two case studies: a close-range (<1 km) vertical glacier calving front reconstructed from two cameras at Fountain Glacier, Nunavut and a long-range (>3 km) scene of relatively flat glacier ice reconstructed from four cameras overlooking Nàłùdäy (Lowell Glacier), Yukon, Canada. We assessed the accuracy of the georeferencing by comparing the UPC to the RPC, as well as surveyed control points; the consistency of the registration was assessed using the difference between successive registered surfaces in the time series. The accuracy of the registration is roughly equal to the ground sampling distance and is consistent across time steps. These results demonstrate the promise of the approach for easy-to-implement georeferencing of point clouds from terrestrial imagery with acceptable accuracy, opening the door for new possibilities in remote monitoring for change-detection, such as monitoring calving rates, glacier surges, or other seasonal changes at remote field locations.Item Contextualizing a Scandal: A Brief History of Library and Archives Canada(Active History, 2024-04-29) Robichaud, DanielleIn his recent callout “LAC: The scandal of the Archives”, Allan Greer shared his experience conducting research over the course of several decades at what is today Library and Archives Canada (LAC). There, he outlines how a shift from user-centered public services and spaces, driven by the expertise of trained archivists, has impacted LAC’s ability to support the meaningful use of its research collections. In doing so, the disjointed state of LAC’s online records is singled out as a point of divide between then (a golden era of people focused spaces and services) and now (a good-luck-out-there era of “digitize it” consequences). Greer calls the state of LAC and its services scandalous. To fully understand the extent to which his claim rings true, however, the context in which this situation arose must be made clear.Item The Public Health Implications of the Legalization of Recreational Cannabis: Ontario Public Health Association Position Paper(Ontario Public Health Association, 2020-09) Akhigbe, Juliet; Ebbadi, Vash; Huynh, Katie; Leckie, James; Major, Maria; Robinson, Cara; Suarly, Michelle; Wasserstein, DavidThe Ontario Public Health Association (OPHA) is a member-based, not-for-profit association that provides leadership on issues affecting the public’s health and strengthens the impact of those who are active in public and community health throughout Ontario. OPHA has multiple active work groups and task forces that focus on particular public health issues. OPHA’s Cannabis Task Group has focused on developing a comprehensive analysis and literature review to inform the development of a policy position statement on the public health impacts of the upcoming legalization of cannabis in Ontario and Canada. Specific reference and considerations were paid to the context, populations, potential challenges and health equity as they relate to Ontario.Item Systematic literature review of SARS-CoV-2 seroprevalence surveys in Canada through April 2021(Elsevier, 2022-09) Major, Maria; Majowicz, Shannon E.; Oremus, Mark; Jimenez, Laura Juliana; Angulo, Frederick J.; Horton, SusanObjectives: To estimate the proportion of the population infected by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in Canada through April 2021, 16 months into the coronavirus disease 2019 (COVID-19) pandemic and 4 months after COVID-19 vaccines became available. Methods: Publication databases, preprint servers, public health databases and the grey literature were searched for seroprevalence surveys conducted in Canada from 1 November 2019 to 10 July 2021. Studies were assessed for bias using the Joanna Briggs Checklist. Numbers of infections derived from seroprevalence estimates were compared with reported cases to estimate under-ascertainment ratios. Results: In total, 12 serosurveys with 210,321 participants were identified. Three (25%) serosurveys were conducted at national level, one (8.3%) was conducted at provincial level, and eight (66.7%) were conducted at local level. All 12 serosurveys had moderate or high risk of bias. The proportion of the population infected by April 2021 was low (2.6%). The proportion of the population infected was higher in surveys of residents of long-term care facilities (43.0-86%), workers at long-term care facilities (22.4-32.4%), and workers in healthcare institutions (1.4-14%). Conclusions: As of April 2021, the proportion of the population infected by SARS-CoV-2 was low in the overall population of Canada, but was high in healthcare facilities, particularly long-term care facilities, supporting the need for vaccines.