30921 research outputs found
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Effects of enhanced monitored natural recovery of conventional heavy crude on biofilm and phytoplankton at the IISD-Experimental Lakes Area, Northwestern Ontario
No full textThe Freshwater Oil Spill Remediation Study (FOReST) evaluated the effectiveness and environmental impact of enhanced monitored natural recovery following simulated spills of conventional heavy crude oil into shoreline enclosures (5 x 10m) of a boreal lake. Six enclosures, equally divided into treatment and reference groups, were used in this study. Remediation included the flushing of trapped conventional heavy oil and recovery with sorbent pads, and a secondary remediation method referred to as enhanced monitored recovery (eMNR), which includes the addition of nutrients to stimulate microbial and algal oil-degrading activity. Effects were then studied on phytoplankton, biofilm growth and community dynamics over 400 days. Chlorophyll a concentration, ash-free dry mass (AFDM) and algal taxonomy were not significantly different between the treatment and reference enclosures. Therefore, we concluded that the eMNR secondary remediation treatment did not affect the phytoplankton and biofilm community but continued monitoring for eutrophication should be conducted to reduce the risk of environmental degradation.February 202
Cannabis use and psychotherapeutic outcomes for PTSD in Canadian military and veterans
No full textCanadian Armed Forces (CAF) members and veterans are increasingly choosing cannabis to manage mental health symptoms, including those of Post-Traumatic Stress Disorder (PTSD). Although psychotherapeutic treatments are recommended for PTSD, there is a lack of high-quality research regarding the potential impacts of cannabis use on treatment outcomes. The little research that has examined cannabis use and psychotherapeutic treatment for PTSD has produced mixed results. There is also a lack of detailed information on cannabis use characteristics (e.g., frequency, THC potency, CBD:THC ratio) of CAF members and veterans and how these may relate to treatment outcomes. Further, little is known about CAF members’ and veterans’ experiences of cannabis use during psychotherapeutic treatment. This study utilized a pre-post-follow-up design to examine psychotherapeutic treatment outcomes of 11 treatment-seeking CAF members and veterans with clinical or sub-clinical PTSD. Multilevel modelling was used to compare outcomes of those who use cannabis (n = 4), and those who did not use cannabis (n = 7). No statistically significant results were found, however the comparison was of low power due to sample size. A regression analysis examined the potential relationships between cannabis-use characteristics and PTSD symptoms at pre-treatment (which included all participants who for whom there was adequate data), however, again, there were no statistically significant results and the analysis was of low power (n = 9). Descriptive results on cannabis use characteristics highlighted a high degree of heterogeneity even in the small sample suggesting that future research that measures cannabis in a more detailed way may aid in clarifying the currently mixed findings. Thematic analysis of open-ended questions highlighted several important themes regarding factors influencing cannabis use decisions and experiences. Careful consideration of both benefits and drawbacks of cannabis, as well as personal beliefs and history, appear to play important roles in cannabis use choices and experiences. Clinicians could benefit from the knowledge that cannabis use varies considerably in this population, and from understanding factors that may relate to their clients’ cannabis use decisions and experiences. Clinicians could use themes identified in this study as starting points for more informed conversations around cannabis use with clients.Royal Canadian Legion
Canadian Institute of Military and Veteran Health Research
University of ManitobaOctober 202
Application of smart sensors to monitor the interactive effects of temperature and lighting on plant growth in a simulated controlled environment facility
Get PDFThis thesis explored the potential use of smart sensors to monitor and integrate multiple environmental factors that play crucial roles in the intricate dynamics of plant growth in response to varying environmental conditions, such as lighting and temperature in controlled environment crop production systems.
A controlled environment chamber was designed and built to conduct experiments across a range of temperatures (15 - 35C) and under varying lighting duration (7, 10 and 14 h) and intensity (100 and 150 µmol/m2.s). A set of wireless smart sensors were used to monitor the environmental conditions, including air and soil temperatures, relative humidity, light intensity, and carbon dioxide level. The study demonstrated that the wireless smart sensors were effective in collecting reliable data for monitoring the environmental conditions, and sensor data could be fused to optimize the environmental conditions for plant growth. From the sensor data, it was found that both fresh biomass and dry biomass were significantly influenced by the three tested environmental factors. The highest biomass accumulation was observed at moderate temperatures (25-27C), with diminished growth at both lower and higher temperatures. Light duration and intensity were found to have a noticeable effect on biomass production, with longer lighting periods and higher intensity fostering greater fresh and dry biomass production. Similar effects of environmental conditions on leaf development were found: the best environmental condition was the moderate temperatures and long lighting duration and high light intensity. However, the benefits of increased lighting were modulated by temperature, indicating a complex interplay between these factors.
This study contributed valuable insights into the optimization of environmental parameters for plant cultivation in controlled environment systems through the use of smart sensors. The findings highlighted the importance of carefully balancing temperature and lighting conditions to maximize plant growth. The study demonstrated the successful use of an array of wireless smart sensors in monitoring multiple environmental parameters in controlled environment crop production and multiple sensor data could potentially be fused to optimize the environment in smart vertical farming (plant factories).October 202
Integrating culture: evaluating the process to adapt evidence-based programs for Indigenous mothers & children impacted by intimate partner violence in Canada
Get PDFObjective: To conduct a process evaluation of a pilot intervention program, culturally adapted using a Two-eyed Seeing approach, and designed specifically for Indigenous mothers and their school-aged children who have been impacted by intimate partner violence (IPV) and who are living in Calgary, Alberta in Treaty 7 Territory.
Background: IPV perpetuated against Indigenous women in Canada is a persistent public health issue and human right abuse, with serious impacts for women, their children, their families, and society as a whole. Alberta ranked fourth highest among the ten provinces in 2020 for its rates of IPV and services, including Calgary’s shelters, are bursting at capacity. Sorely lacking is programming that is a) culturally integrated for an Indigenous population, b) evidence-based, c) specific to IPV, and d) being delivered to both mothers and their children concurrently.
Research Design: The first research question addressed the perspectives of and lessons learned by those involved in the adaptation process. The second question investigated how the culturally responsive elements or concepts of the adapted programs were chosen, particularly around fit, familiarity, and meaningfulness. The results shone a light on how the effort to build relationships, renegotiate power, and integrate Indigenous cultural representation would come to define how the process through it went for the team. Six themes were identified from the transcripts: Power, Adaptation Barriers, Relationship Building, The Learning Journey, Integrating Indigenous Cultures, and Outcomes of the Adaptation Process.
Conclusion: Bringing to light the experiences of those involved in this adaptation process, allowed for a deeper understanding of the positive and negative aspects of how the process unfolded, and provided clear recommendations concerning how others may undertake a similar process for their own communities. Creating a map of how it can be done is one way research becomes reciprocal with potential benefits for generations to come.The Manitoba Metis Federation
Indspire
The Manitoba Provincial Chapter of the P.E.O. Sisterhood
University of Manitoba Faculty of Graduate StudiesMay 202
Elite-driven support vector machines for classification
Get PDFIn the field of Support Vector Machines (SVM), the traditional approach to classifier construction relies heavily on a set of observations known as support vectors, determined by the choice of loss functions. Each loss function results in a specific decision boundary and identifies a unique set of support vectors, leading to varied classification performances. This thesis proposes a novel SVM methodology that gives additional weight to a curated collection of elite observations that play crucial roles in constructing SVM decision boundaries under various loss functions. These elite observations are identified through their recurring presence as support vectors in different SVM configurations using diverse loss functions. We develop new loss functions to emphasize the importance of these elite observations during the training of our SVM classifiers. The loss functions for the Elite-Driven Support Vector Machine (EDSVM) are designed to be classification-calibrated, ensuring theoretical soundness while enhancing the model's focus on these elite observations. Rigorous theoretical results are provided, and a comprehensive numerical data analysis is conducted to evaluate the EDSVM's performance across various datasets. The novel SVM models developed in this research demonstrate superior performance compared to conventional models studied in this thesis. This is evidenced through both simulation studies and real data analyses, applicable to both linear and non-linear classification tasks.October 202
The utility of three-dimensional modeling and printing in pediatric surgical patient and family education: a systematic review
Get PDFBackground
Three-dimensional (3D) modeling and printing are increasingly being used in surgical settings. This technology has several applications including pre-operative surgical planning, inter-team communication, and patient education and counseling. The majority of research on 3D technology has focused on adult populations, where it has been found to be a useful tool for educating patients across various surgical specialties. There is a dearth, however, of research on the utility of 3D modeling and printing for patient and family education in pediatric populations. Our objective was to systematically review the current literature on how this modality is being utilized in pediatric surgical settings for patient and family education and counselling.
Methods
We conducted a systematic review in accordance with PRISMA and CASP guidelines. The MEDLINE, CINAHL, Embase, and Web of Science databases were searched from inception to October 21, 2023, with no restrictions on language or geographical location. Citation chaining was used to ensure relevant papers were included. Articles were doubly screened and data was extracted independently by two authors. In the case of disagreement, a third author was consulted. Any articles pertaining to 3D modeling and printing in pediatric surgical settings for patient and family education and counseling were included.
Results
Six articles met inclusion criteria and were used for qualitative analysis. Two involved questionnaires given to parents of children to assess their understanding of relevant anatomy, surgical procedure, and risks after viewing conventional CT images and again after viewing a 3D-printed model. One involved a quasi-experimental study to assess young patients’ pre-operative surgical understanding and anxiety after undergoing conventional teaching as compared to after viewing a 3D storybook. One involved questionnaires given to parents of children in control and study groups to assess the usefulness of 3D printed models compared to conventional CT images in their understanding of relevant anatomy and the surgical procedure. Another study looked at the usefulness of 3D printed models compared to 2D and 3D CT images in providing caregiver understanding during the pre-operative consent process. The last article involved studying the impact of using 3D printing to help patients understand their disease and participate in decision-making processes during surgical consultations. In all six studies, utilizing 3D technology improved transfer of information between surgical team members and their patients and families.
Conclusion
Our systematic review suggests that 3D modeling and printing is a useful tool for patient and family education and counselling in pediatric surgical populations. Given the very small number of published studies, further research is needed to better define the utility of this technology in pediatric settings
Pebbling in Erdős-Rényi random graphs
Get PDFGraph pebbling is a game in which a collection of pebbles is placed on the
vertices of a connected graph. A pebbling move consists of removing two
pebbles from one vertex and placing a pebble on any adjacent vertex. Of
interest is the pebbling number of a graph G: the least k such that for any
collection of k pebbles on V(G) and any target v ∈ V(G), there exists a
sequence of pebbling moves placing a pebble on v. It is well-known that the
pebbling number of a graph G is at least |V(G)| and is, in general, bounded
above by an exponential function of |V(G)|. The Erdős-Rényi random graph
model has frequently been used to address questions relating to the ‘typical’
behaviour of a graph with regards to some interesting property. This model
has been used to show that almost all graphs G with at least a constant
fraction of the possible edges have pebbling number |V(G)|. In addition to a
survey of selected pebbling results and techniques, this thesis presents a first-
of-its-kind result showing that even amongst graphs with a much smaller
proportion of edges, graphs of large pebbling number are rare: almost all
graphs on n vertices and more than (nlogn)/2 edges have pebbling number
bounded above by a linear function of n – significantly smaller than the
exponential in n bound for arbitrary graphs. Furthermore, it is shown that
almost all graphs on n vertices with more than (n/2)exp(√log n) edges have
pebbling number n, an improvement over the current best result. Various
additional original results are given, including a strongly improved upper
bound on the pebbling number of the Kneser graph Kn(7,3).University of Manitoba Department of MathematicsFebruary 202
Examining the associations between social anxiety and cannabis outcomes in emerging adulthood
Get PDFEmerging adulthood is a developmental period where cannabis is used at higher rates compared to other age groups. Social anxiety, a condition defined as being fearful of negative evaluation from others, is also prevalent in emerging adulthood and may be related to cannabis outcomes. Tension reduction theory posits that individuals with social anxiety use cannabis to reduce unpleasant emotions from perceived negative interactions. Research demonstrates that social anxiety and cannabis are related in adulthood; however, the literature in emerging adulthood is mixed. The overarching goal of this dissertation was to elucidate the association between social anxiety and cannabis outcomes in emerging adulthood by (a) quantifying the strength of the association between social anxiety and cannabis outcomes in the extant literature and (b) examining contributing factors to this association. Study 1 (k = 18) used meta-analytic methods to establish the magnitude of the associations between social anxiety and cannabis-related variables. Results supported a small significant (but negligible) positive association between social anxiety and cannabis problems, but not cannabis use frequency, in emerging adulthood. Study 2 (N = 5,194) used epidemiological data from a nationally representative sample in the United States to explore what sociodemographics and psychiatric disorders may be associated with co-occurring social anxiety disorder (SAD) and cannabis use in emerging adults. Results revealed that being White, a part-time student, or not a student were associated with increased odds of having co-occurring lifetime cannabis use and SAD. Additionally, having major depressive disorder, bipolar I disorder, generalized anxiety disorder, specific phobia, agoraphobia, and panic disorder were associated with increased odds of having co-occurring lifetime cannabis use and SAD. Study 3 (N = 269) used a mediated moderation to test negative urgency and sex as moderators that may strengthen the associations between social anxiety and cannabis outcomes in emerging adults. Results revealed that higher social anxiety predicted elevated cannabis use and problems via coping motives, but only for males higher in negative urgency. Overall, this work expanded our understanding of the associations between social anxiety and cannabis outcomes among emerging adults. Results have implications for informing screening approaches in this population.October 202
Mercury emissions from Icelandic volcanism
No full textMercury (Hg) is a naturally occurring metalloid element and an environmental contaminant of global concern. It can be emitted to the environment from anthropogenic activities, such as fossil fuel combustion, as well as through natural emissions, such as volcanic activity. While anthropogenic Hg emissions have been fairly well constrained and are projected to decline with recent emission reduction efforts, there remain major uncertainties in the amount of Hg emitted from volcanoes due to a scarcity of field measurements, methodological uncertainties, and the diversity of Earth’s volcanism over space and time. This is an important knowledge gap because evaluating the effectiveness of Hg emission regulations such as the Minamata Convention on Mercury requires sufficient knowledge of both anthropogenic and natural inputs to the global Hg cycle. This thesis reports the results of four field campaigns from 2019 to 2022 on the highly active volcanic island country of Iceland. During the 2021 and 2022 effusive eruptions of the Fagradalsfjall volcanic system, Hg was measured in the volcanic plume by drone directly above the active vent (a first for volcanic Hg research) as well as at more distant downwind locations, with a relatively low time-averaged Hg flux of 84 ± 62 kg a–1 for these eruptions. To assess the role of geothermal degassing in Iceland’s natural Hg emissions, we measured soil gaseous elemental mercury (GEM) concentrations at six geothermal fields and used an adapted gradient method to estimate soil–air fluxes. These yielded similarly low GEM emission figures: an estimated Icelandic geothermal flux of 1.8 kg a–1 and a total Icelandic flux (including non-geothermal areas) of ~18 kg a–1. Despite the minor geothermal flux, soil gas GEM concentrations at 10 cm depth were often hundreds and in some cases thousands of times higher than surface air concentrations, and geothermal soils showed major enrichments in total Hg (THg). This thesis shows that Icelandic geothermal activity can generate extreme gas and soil Hg enrichment in the local environment, but its contribution to global Hg cycling appears to be minor, at least outside of large explosive eruptions where no data are currently available.Research Affiliate Program (RAP) funding provided through the Environmental Geosciences Program of Geological Survey of Canada (Natural Resources Canada).
Canada Research Chairs (CRC) Program funding as part of supervisor base funding (F. Wang)May 202
Access Barriers Among Transgender and Gender Diverse Youth Seeking Gender-Affirming Care in Canada: A Literature Review
No full textIntroduction: There are increasing numbers of Canadian youth who identify as genders different from their assigned sex at birth. As a result, healthcare providers are encountering more transgender and gender diverse (TGD) youth seeking gender-affirming healthcare. Unfortunately, due to the effects of gender identity-related stigma, as well as distress related to the development of secondary sex characteristics during puberty, TGD youth often have complex medical, psychological, and social needs, and face high levels of social adversity, adverse mental health outcomes, substance use, and suicidal ideation. Research provides increasing evidence that access to gender-affirming care (GAC) is crucial in improving the health and social functioning of TGD youth. Unfortunately, many Canadian TGD youth are unable to access the GAC that they need, due to numerous provider, patient and systemic barriers. Objectives: The purpose of this literature review is to identify the barriers that Canadian TGD youth face when accessing GAC, and to investigate possible solutions that can be implemented within the healthcare system to improve access to GAC for this population. Additionally, this literature review will investigate how Physician Assistants (PAs) may have a role in improving this population’s access to GAC. Methods: A literature search using PubMed and Scopus databases was performed using key terms pertaining to access barriers to gender-affirming care among TGD youth in Canada. Seven articles were found to meet the inclusion criteria and were analyzed in this literature review. Results: Seven studies explored the challenges that TGD youth in Canada experience when accessing gender-affirming care. Six studies investigated potential modifications that may be implemented to improve accessibility of GAC for TGD youth in Canada. No research was found concerning how PAs may assist in the provision of GAC for TGD youth in Canada. Conclusion: The barriers to GAC for TGD youth in Canada identified in this literature review concern delayed access to care, challenges related to systemic health system issues, lack of provider knowledge or sensitivity, and financial constraints. Strategies to improve access to GAC for TGD youth include increasing training and knowledge of all providers in GAC; advocating for policy changes to make GAC more accessible; and requiring staff of medical facilities to undergo gender-sensitivity training