Open Access Journals University of Manitoba
Not a member yet
139 research outputs found
Sort by
Characterizing the Spatial Heterogeneity of Basic Physical Properties of Lake and Peat Soils as it Relates to the Moss Spur Peatland, Manitoba
Get PDFMoss Spur (the study site) is a remnant vacuum-harvested peatland in south eastern Manitoba that has, with little intervention, revegetated on its own. It is quite atypical that Moss Spur has revegetated with little intervention. As part of unraveling this mystery, this study investigates the spatial heterogeneity of vegetation and underlying lake sediments at Moss Spur. Physical properties like hydraulic conductivity, bulk density and porosity relate to hydrology and the ability of water to flow, which are of importance in this study. This study looked at those properties and attempted to find a connection between the physical properties of the peat and underlying sediments and the heterogeneity of surface vegetation found at different study areas at Moss Spur. Peat cores as well as sediment cores were extracted from sub-locations within sites. Sample cores where tested via a variety of methods to establish their physical and hydraulic properties. Heterogeneity based on core samples was revealed between sites matching the general heterogeneity of surface vegetation at Moss Spur. This study presents some regionally key aspects to understanding groundwater relationships with respect to harvested bogs and Manitoba wetlands in general. The variability in lake sediment properties across even the relatively small site of Moss Spur suggests that lake sediment properties cannot be assumed to be the same at every location. Heterogeneity of the surface vegetation in regards to the spontaneous regeneration is found to be correlated with the underlying peat and lake sediments
Social Behaviour and Trophic Interactions of Gray Wolves (Canis lupus), the Keystone Species in Yellowstone National Park
No full textThe gray wolf (Canis lupus) is an apex predator described as a keystone species in Yellowstone National Park (YNP). Their importance in this habitat was unknown until they were anthropogenically extirpated in the 1920s. The 75-year absence of gray wolves in YNP led to severe declines in biodiversity, species richness, and habitat quality, all of which were reversed upon wolf reintroduction in 1995. Complex social behaviours and trophic interactions are the driving forces behind the gray wolves’ ability to directly and indirectly provide benefits for almost all species of fauna and flora within Yellowstone National Park. This paper reviews how wolves’ interactions with trophic level as well as animal behavioural changes have helped in reshaping the dynamics of Yellowstone National Park
Construction of A-optimal Designs for Linear Models
Get PDFFor estimating parameters of a statistical model, it is important to minimize the variances of the estimators. Efficiency of an estimator increases as its variance becomes smaller. Sometimes instead of minimizing the variances of the individual parameters, it is important to minimize the total or average variance of all the parameter estimators. This refers to A-optimality in the context of optimal experimental design. Motivated by this fact, we construct A-optimal designs for some regression models using a class of algorithms, indexed by a function which depends on the derivatives of the criterion function. We also develop strategies for constructing A-optimal designs and investigate techniques for improving convergence rates by using the properties of the directional derivatives of the criterion function. We explored the design construction through some examples including one practical problem arising in chemistry
A Perspective on the Economic Sustainability of the Physician Assistant Profession in Canada
Get PDFPhysician Assistant funding is about dollars and cents, but will we have those dollars if we don’t apply common sense? The physician assistant (PA) role represents one of the most revolutionary and yet financially subversive additions to our current health care system. PAs are medically educated clinicians whose generalist training allows them to work in any setting within a formalized agreement with a physician. When used to their full capacity, PAs help supplement physician care, increase patient access to care, and improve efficiencies.  Despite provincial interest in improving access and delivering cost-effective and efficient health care, our healthcare system rarely factors in the opportunity costs and comparative advantages offered by the introduction of PAs. This paper outlines the importance of increasing Government and employer awareness of sustainable funding models and the growing need to develop alternative policies to support PA utilization to optimize healthcare delivery. If the effectiveness of the PA role comes down to dollars and cents, then it is time to examine those dollars using common economic sense to ensure a sustainable and accessible healthcare system for all Canadians
Impact of Drainage Ditch Construction and Subsequent Use on a Treed Bog Adjacent to a Peat Harvesting Operation, Southwestern Manitoba, Canada
Get PDFManitoba has the most peatland by provincial area of any province in Canada, and contributes ~13% of Canada’s horticultural peatland production. Peat harvesting requires the lowering of the water table; this water is usually channeled to a fluvial system (e.g., a river) but in some cased must be actively pumped. In the case of the South Julius bog in Manitoba, the pumped discharge was through a treed bog. The trees in the bog on one side of the drainage ditch were dead, but on the other side were alive. This study investigated possible hydrological causes by instrumenting three transects of wells that ran perpendicular to the drainage ditch and extended 20 and 50 m into the bog on the dead and live side, respectively. Average water tables on the live side were 15 cm lower than the dead side. The dead side water levels were similar to a natural fen located adjacent to the treed bog. Construction of the drainage ditch yielded a >20 cm high berm that ran alongside the live side, functionally isolating the live side from the surplus water in the drainage ditch, maintaining the lower and healthier water table treed bog vegetation requires. We recommend that future drainage ditches be constructed in such a way that berms on both sides are made, functionally creating a canal to the fen, where the excess water can be more easily dealt with by the fen vegetation adapted to wetter average conditions
LETTER FROM THE EDITORS Vol 1 (1) 2018
Get PDFOn Canada Day, July 1, 2018, we are very pleased to present the first edition of the Journal of Canada’s Physician Assistants (JCanPA). It has been a project long deserving of the physician assistant (PA) profession, enabling a platform for exemplifying the professionalism, expertise, and excellence of PAs in Canada.Thank you to our families, readers, authors, reviewers, supporters, mentors, and especially our teachers who without their support we could not make as big a difference we do.Enjoy and start writing. We are here and waiting for your stories
Evaluation of Punching Shear Strength Models for Glass Fibre-Reinforced Polymer (GFRP)-Reinforced Concrete (RC) Flat Plates Subjected to Unbalanced Moment-Shear Transfer
Get PDFThe provisions for the punching shear strength of glass fibre-reinforced polymer (GFRP)-reinforced concrete (RC) flat plates in the current North American and Japanese standards were investigated based on a database of experimental results of both interior and edge slab-column connections. In total, the results of 39 slab-column connections ranging extensively in their geometric and material properties were collected from the literature and analyzed to assess the accuracy and validity of the code provisions. In addition, the applicability of eight proposed analytical models from the literature was verified against the results of the dataset. It was demonstrated that the Canadian and Japanese standards provide the most consistent and accurate predictions; however, the American guidelines highly underestimate the capacities. In contrast, many of the proposed analytical models yielded inconsistent and unsafe estimates when applied to both concentrically and eccentrically loaded interior and edge connections. The assumption of a linear stress variation proposed by the eccentric shear stress model was validated for GFRP-RC edge specimens subjected to unbalanced moment-shear transfer.Â
Analysis and Prediction of Patterns in Futures Trading Datasets Using LSTM
Get PDFOne of the most promising tools in recent years for the analysis and prediction of time series data, which includes financial market data has been the use of neural networks. To ensure the accuracy of the outcomes of these systems, it is critical to overcome the vanishing gradient and exploding gradient problems that often occur when recurrent neural networks (RNN) process data. Long Short-Term Memory (LSTM) has been shown to provide good performance when dealing with time series datasets. This paper will explore the feasibility of using an RNN with LSTM as a predictive tool for use with futures trading data. Using a dataset comprised of all futures trading occurring on the Bourse de Montréal (TMX) during a 9-month period from January to September 2015, we assessed the predictive effectiveness of an RNN in predicting the price of front-end contracts for the futures symbol BAX. We found that while an RNN provided a degree of short-term predictive capability, this capability did not extend beyond a couple of days. Although it failed as a trading instrument to predict futures prices, the RNN could detect, identify, and reflect underlying trends in the data, indicating the tool may hold promise in the detection of trading patterns.Â