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Braiding Knowledge Systems : Learning the value of what we don’t know
Get PDFCanada First Research Excellence FundNon-Peer ReviewedExperience of a Global Water Futures researcher in exchanging knowledge with an Indigenous community affected by water problems
Performance of an integrated modeling framework for spring wheat yield simulation in Canadian Prairies
Get PDFGlobal Water FuturesCanadian Prairies produce more than 90% spring wheat of Canada.
Most of the agricultural area is rain-fed in Saskatchewan, which is affected by climate significantly.
Crop model is a good tool to simulate the growth of a crop and evaluates the effects of climate on crop yield.
The simulation period in this study is from 1981 to 2016
The influence of roads on depressional storage capacity estimates from high-resolution LiDAR DEMs in a Canadian Prairie agricultural basin
No full textThis is an original manuscript of an article published by Taylor & Francis in Canada Water Resources Journal on 26 July 2023, available at: https://doi.org/10.1080/07011784.2023.2235756Canada First Research Excellence FundPeer ReviewedThe Canadian Prairies are a post-glacial agricultural landscape, where millions of small depressions store surface water, form wetlands and control runoff contributing area. Their management is key to flood and drought hydrology, groundwater recharge, ecological integrity, migratory bird habitat and agricultural productivity. Depression drainage and infilling is common in the region, where it is often used to increase cropped area. The regularly spaced, rural ‘grid-road‘ network also impedes drainage, but associated culvert drainage can mitigate those effects. Management of depressions can be informed by hydrological modelling, but accurate surface water storage capacity estimates are needed to ensure accurate model results. Simple representation of road embankments in digital elevation models (DEMs) neglects the effects of culvert drainage. Here, a raster-based depression-filling algorithm was used to delineate depressions from three LiDAR-derived DEMs: a 10-m DEM with roads intact, a 2-m DEM with roads intact, and a 2-m DEM with roads breached at culvert locations. Road breaching was conducted manually in the 2-m DEM to remove artifact depressions that form alongside roads where culverts exist. Results indicated that increasing DEM resolution from 10-m to 2-m in a 393.5 km2 basin did not significantly change depression area or storage capacity estimates; however, breaching roads in the 2-m DEM decreased depression area by 29% (from 98.5 km2 to 69.8 km2) and estimated storage capacity by 48% (from 47.4 × 106 m3 to 23.8 × 106 m3), compared to leaving roads intact in the 2-m DEM. Depressions delineated from the 2-m roads-breached DEM also covered 48% more area and offered 53% more storage capacity than Canadian Wetland Inventory (CWI) aerial-photograph delineated wetlands, which occupied 47.1 km2 with an estimated storage capacity of 15.5 × 106 m3. The implications of these results for the ability of hydrological models to calculate runoff contributing areas and streamflow are discussed
Joint Models for Recurrent Event data Combining with a Longitudinal Internal Covariate
Get PDFIn many clinical trials, both longitudinal measurements and time-to-event data are frequently observed
and collected within the same study. However, they are typically analyzed separately, which can lead to
biased results due to measurement errors and missing information. The modern approach to analyze such
data when both longitudinal and time-to-event responses are available is to jointly model the two processes, a
framework in which potential underlying relationships between the two processes are explicitly acknowledged.
Combining the two processes also enables us to mutually borrow information from each process and gain
efficiency in statistical inference. For this reason, the joint modeling approach has gained considerable
attention in recent years. The primary goal is to investigate the relationship between the two processes, and
ultimately to estimate the effects of the longitudinal response on the survival outcomes.
A typical joint modeling setup involves describing the longitudinal process by a linear mixed-effects model,
and the time-to-event process by a parametric survival model. The motivating concept behind the joint modeling
technique is to connect the time-to-event model with the longitudinal process through shared random
effects. Note that a non-parametric method for the time-to-event process often leads to an underestimation
of the standard errors of the parameter estimates. Therefore, joint models based on parametric response distributions
are typically considered in the literature. The parametric methods for time-to-event data analysis
broadly fall into two families: proportional hazards (PH) and the accelerated failure time (AFT) models. In
this thesis, we focus on modeling the time-to-event process using an AFT model (the use of a PH model is a
topic for future research). Note that although a PH model is widely used to describe a time-to-event process
because of its relative risk interpretation, an AFT model is particularly useful when the PH assumption is
violated.
While most studies on joint modeling focus on a single outcome event for the survival process (e.g.,
death or recovery from a disease), some literature extends this method to multiple events. For example,
in a long-term follow-up study the occurrence of the event of interest may not necessarily be a one-time
event but rather an individual can experience the event multiple times over a specified period of time (e.g.,
recurrent asthma attacks). Such processes are called recurrent event processes, and the data generated by
these processes are called recurrent event data. In this thesis, we propose a joint modeling approach that
combines recurrent event data with a longitudinal response (the longitudinal response serves as a covariate
for the recurrent event process, commonly called an internal time-dependent covariate). For example, serum
bilirubin is a surrogate marker (longitudinal response) for time to blood vessel malformations in the skin
(recurrent event process), and we would like to model the time-to-event to investigate the effects of serum bilirunbin on the risk of blood vessel malformations in the skin. As mentioned above, we focus on AFT models
to describe the recurrent event process. We propose a general framework for joint models, and develop a
Bayesian method for statistical inference. We also propose generalized residuals for goodness-of-fit of a joint
model, and develop computational algorithms for data analysis. Our simulation study demonstrates that
the proposed methodology performs well for joint analysis of recurrent event and longitudinal data. We also
demonstrate the application of the proposed methodology with two real data examples of scientific interest:
(1) colorectal cancer data to investigate the effects of tumor size (internal covariate) on the occurrences of
new lesions (recurrent events), and (2) primary biliary cirrhosis (PBC) of the liver data to investigate the
association between serum bilirubin and blood vessel malformations in the skin.
Overall, our work holds significant value in the joint model of recurrent events, both in theory and applications.
The proposed joint model offers a versatile approach for modeling recurrent events by accommodating
various distributions within the AFT framework
The Pedagogy of Mystical Praxis and The Problem of the Self-Knowing: An Institutionalizable Approach for Combating Contemporary Socio-Ecological Degradation
Get PDFAbstract: This thesis comes in response to contemporary concerns over (socio-)ecological degradation and the question: How can we institutionalize transformation into our presently dysfunctional system? I offer the field of mystical praxis as an academic consideration. In the minds of many, the contemporary state of socio-ecological degradation (i.e., the climate crisis, social injustice, etc.) ranges between the apocalyptic and the apocryphal. Among the responses there has been a strong shift in thinking and approach towards the spiritual and the mystical. In much of the dialogue on ecology, such as within Laudato Si’ and The Great Work, contemplation is taken as a frontal assault on the socio-ecological crisis through didactic, dialectic dialogue encouraging people to be more holistically oriented. This whole dialogue is spiritualized and often has mystical undercurrents of encountering beauty. All of these approach mysticism as a transformational human activity. Having experienced what I argue is a mystical encounter myself, I can attest that this benevolent and anthropocentric approach to mysticism errs in telling only a portion of the story on contemplation. This thesis aims to offer a fuller story for mysticism within academia. I appeal to St. Teresa of Avila’s The Interior Castle as a suitable textbook for contemporary (Catholic) institutions of education to employ as a way to begin to institutionalize transformation through systemic self-reflective knowing. The contemporary crisis has much deeper roots than most commentators ascribe in the ideas of socialized anthropocentrism and the instrumentalization of nature. This is The Problem of the Self-Knowing, or the problem of the human being a self-knowing creature capable self-willing resulting in the development of material culture. Mysticism, as the practice of knowing one’s Self [i.e., self-reflection], is a discipline of knowledge currently missing from the institutional socialization of western youths and should be taken seriously as a field of study which might help reconstitute the epistemology and methodology of the educational system thereby institutionalizing transformation into the infrastructure of contemporary Western society
Global Water Futures Equity, Diversity, and Inclusion Events Protocol
Get PDFGlobal Water FuturesThe core objective of the Equity, Diversity, and Inclusion (EDI) Events Protocol is to ensure that
events that further dialogue in water research and management, are open to a diverse range of
participants, offer equitable pathways to participation, and foster inclusive experiences
leading to inclusive water solutions. Events from small gatherings to multi-day conferences are a critical platform for scientific debate, community engagement, and more. As such, considering
equity, diversity, and inclusion in event planning, organization, and content strengthens long-term inclusion in water
Hudson Bay on the World Stage : To dam a river is to dam the world
No full textCanada First Research Excellence FundNon-Peer ReviewedExperience of a Global Water Futures researcher in explaining the environmental consequences of development to a non-scientist
Nursing the Province Back to Health: Spanish Influenza and its Impact on Saskatchewan Women
No full textIn 1918, the world experienced a pandemic that was unlike any that came before it. A truly global event, Spanish influenza was incubated and mutated in the trenches of the First World War and was shipped across oceans and permeated across borders in the bodies of returning military men. It gained massive coverage in local and international newspapers and was exploited by patent medicine companies to hawk their remedies. In Saskatchewan, Spanish influenza deeply impacted both urban and rural communities, taking thousands of lives in three short months. Surprised by the severity of the diseases, the province’s Bureau of Public Health was quickly overwhelmed. Using social and digital history methodologies to analyze digitized newspaper, trade journals and other online sources, I argue that the labour of Saskatchewan women was a critical yet deeply undervalued aspect of the province’s pandemic response. The pandemic of 1918 not only highlighted the role that women played in their communities but also exposed the gaps and failings of Saskatchewan’s healthcare system, reigniting conversations around practical or “second tier” nurses. The volunteer attendants, women with no formal nursing training, entered homes to care for the sick, keep the fires lit, cook meals and care for children. These attendants provided a framework for a new healthcare provider that was introduced in the province in 1920. I argue that Saskatchewan’s failed nursing-housekeeper program was born from the province’s pandemic response and further undervalued women’s labour by undermining the physical, social, and economic autonomy that women gained from the nursing profession
Short-season high-moisture corn products in western Canadian beef cattle diets
No full textAs low-heat unit corn becomes more abundant in western Canada, alternative utilization methods to corn silage and standing corn for grazing should be investigated. The objectives of this dissertation were to 1) evaluate yield and production costs of low-heat unit, high-moisture shelled corn (HSC) and snaplage; 2) evaluate the potential to utilize low-heat unit, HSC stover in a winter grazing system for pregnant beef cows relative to grazing whole-plant barley in a swath grazing system including system economic costs; 3) characterize low-heat unit HSC stover quality based on each plant component at the appropriate time of harvest and the digestibility of each component; and 4) evaluate the use of low-heat unit, high-moisture corn products (HSC and snaplage) in finishing diets compared to barley grain and silage. Over two consecutive years, high-moisture corn products (HSC, snaplage, and HSC stover) and barley greenfeed (BAR) were produced at the Livestock and Forage Centre of Excellence (LFCE; Clavet, SK, Canada). These products were utilized in five experiments: two in vivo winter feeding studies examining the use of HSC stover compared to BAR as forage for dry pregnant beef cows; one in vitro batch culture study comparing the nutrient composition and disappearance of anatomical components of HSC stover and BAR; one in vivo, metabolism study comparing the previously mentioned diets in site and extent of nutrient digestibility; and one in vivo small pen study comparing performance of steers finished on a traditional barley-based diet and those that substituted barley products with high-moisture corn products. An economic summary based on the results of these studies and crop production data was prepared. Both HSC and snaplage, along with their stovers, yielded less dry matter (DM) than BAR in 2020, but HSC and its stover yielded more DM than BAR in 2021. Production costs ($/ha) were greatest for snaplage, then HSC, then BAR. When HSC stover was swathed, cows performed similarly to those fed swathed BAR, but BAR was more economically favorable. When baled, cows fed BAR had greater final body weights (BW) and body condition scores (BCS), but HSC stover was more economically favorable. In vitro batch culture revealed that BAR leaves had the highest forage quality based on nutritional composition and in vitro fiber disappearance, while HSC stover cobs had the lowest forage quality. In the metabolism study, the barley grain finishing diet was comparable in starch digestion and live performance to a diet substituting 50% of barley grain with HSC (DM basis), but the diet containing HSC yielded heavier carcasses in the performance study. Additionally, when barley silage and approximately 10% of barley grain were replaced with snaplage, there were no differences in live performance of finishing steers, but ruminal starch digestion was more complete in the metabolism study, although severe liver abscesses were less common in the performance study. Substituting snaplage in finishing diets produced lower costs of gain than buying all feeding ingredients, and substituting HSC was more expensive than the traditional barley finishing diet. These results indicate that short-season high-moisture products are acceptable replacements for barley products in western Canadian beef cattle diets, but HSC was not as economically favorable at the time of the current study
Understanding the Energy-Poverty Nexus in Northern, Remote and Indigenous Communities Using a Social Value of Energy Approach
No full textThe transition from conventional fossil fuel-powered utilities towards renewable energy (RE) and alternative socio-technical arrangements has the potential to either alleviate or exacerbate poverty, especially for marginal communities who rely heavily on energy resources for heating and survival, such as Indigenous communities in northern and remote regions. Therefore, there is a need to understand the dynamic interplay between energy and poverty—or the energy-poverty nexus—from the community level using an approach that is holistic and contextual to inform energy transition initiatives, to work towards value generating rather than value eroding outcomes. This thesis does so using the Social Value of Energy (SVE) approach. First, it develops, based on current literature, a conceptual framework to identify the value generating and value eroding outcomes of RE in northern and Indigenous communities, along with the techno-variables that contribute to identified outcomes, and pathways towards value generating outcomes. Next, it applies the framework on a case study with a northern Indigenous community to generate empirical evidence on the SVE in this context. Finally, it elucidates lessons learned about the SVE in northern, remote and Indigenous communities, to advance our understanding of the energy-poverty nexus