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Liminal drift: revealing the human hand in shaping the untouched Great Lake
No full textLake Superior is often perceived as a pristine body of water, the “untouched” or “least spoiled” of the Great Lakes. While Lake Superior’s northern geography has enabled it to escape much of the development of the lower Great Lakes, this does not mean the basin in unshaped by humans – just that the traces are harder to see. The landscapes that serve as the interface between humans and Lake Superior often reduce the landscape to a scenic backdrop, omitting places of human influence to uphold its wilderness status.
This practicum challenges the untouched image of Lake Superior and argues that this over-reduction of landscape prevents meaningful connection with place. An alternative image of Lake Superior is projected through the design of places that make the human role in shaping the landscape perceptible. This is demonstrated through design exploration that engages the dredging cycle of the St. Marys River in Sault Ste. Marie. Dredge material itself hovers somewhere between land and water, human and natural. This liminality is captured through design that seeks to make perceptible the processes of sediment impoundment, release, and accumulation, blurring the line drawn between human and natural systems.October 202
Understanding the role of odorant receptors in Aedes aegypti larvae
Get PDFWorldwide, mosquitoes are of great medical and economic importance due to their profound negative impact on humans. Mosquitoes act as both nuisance pests and disease vectors that account for millions of cases of illness and death annually. They rely on complex olfactory systems for many of their fundamental processes such as finding mates, identifying egg-laying sites, and directly linked to their disease vectoring capabilities, locating blood-meals. Their olfactory systems rely on three major categories of receptors: odorant receptors, ionotropic receptors, and gustatory receptors. These receptors, along with sensors of various environmental cues such as CO2, heat, and humidity, contribute to the mosquito’s chemosensory responses. The yellow fever mosquito, Aedes aegypti, is responsible for the transmission of key diseases such as dengue virus, yellow fever virus, chikungunya virus, and Zika virus. Because of its profound impacts on human health, there is growing interest in exploring new ways to disrupt Ae. aegypti’s olfactory-based behaviours as a means of reducing disease transmission. While there are numerous studies focused on adult mosquito chemoreception, little is known about these processes in mosquito larvae. Here, a chemotaxis response assay was developed to examine which naturally occurring chemicals would attract Ae. aegypti larvae. Mosquito larvae were subsequently fed E. coli bacteria expressing double stranded RNA targeting a larval specific odorant receptor, OR34. RNA interference knockdown of the gene’s transcript was confirmed via qRT-PCR, and chemotaxis assays were used to identify putative odorant ligands to this receptor. This research describes a simple chemotaxis response assay that can be used to identify larval mosquito attractants and an effective way to identify odorant receptors’ potential ligands. Using this information, it should be possible to screen for other ligands that may be used to disrupt mosquito olfaction, and thus develop novel larval mosquito control methods.May 202
It takes a village: rethinking urban spaces for children with ADHD
No full textAttention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder that impacts individuals’ ability to focus, organize, and regulate impulses. In landscape architecture, accessible design can be applied to address ADHD, which can positively impact the urban environment and create a more inclusive space for all. The exploration of this intersection of ADHD and landscape architecture highlights both the challenges and potential strengths of individuals with ADHD. In this way, it can pinpoint the factors contributing to a practical urban space that assists children with ADHD in a neighbourhood.
To understand how to design for children with ADHD, one must first understand what ADHD is and how it affects children in families and their communities. Doing so can help identify the necessity to address the symptoms of ADHD in the urban landscape. Secondly, a neighbourhood analysis is conducted to understand how to design for the neighbourhood of Elmwood in Winnipeg, Manitoba. Through the analysis of ADHD and Elmwood, a universal design can address and respond to the symptoms of ADHD in children to enhance the overall outdoor environment for all.October 202
Design and development of a multimodal nonlinear optical microscope for applications in biosciences
Get PDFNonlinear optical microscopy is an expanding field in the area of optical microscopy applied to biosciences. Methods such as Two-Photon Excited Fluorescence (2PEF or TPEF), Second Harmonic Generation (SHG), Third Harmonic Generation (THG), and Coherent Anti-Stokes Raman Scattering (CARS) constitute an improvement over classical (single-photon) fluorescence microscopy. With them, the need for the use of exogenous labelling agents disappears together with issues such as phototoxicity and photobleaching. These techniques can provide detailed structural images and chemical information from unstained samples. The laser wavelengths used in these methods penetrate deeper into the biological tissues and allow us to obtain images with sub-micron lateral and axial resolution.
In the present work, a multimodal nonlinear optical microscope was designed and developed. In the instrument, the following nonlinear methods were implemented: 2PEF, SHG, THG with CARS being added in the near future. A compact, reliable, and cost-efficient Yb:KGW laser was used as a light source. The low energy (12 nJ) per pulse decreases the amount of damage to the surrounding sample areas. The ultrashort laser pulses provide us with a broad spectrum that makes it easier to find lines that coincide with the absorption spectra of different biological materials. The software for controlling the instrument was also developed in two versions (single-tile and multi-tile). The multi-tile version allows the scanning of larger sample areas by joining several tiles. Finally, conditions were created for future implementation of CARS using the Yb:KGW radiation to provide the Stokes beam and a Photonic Crystal Fiber to generate the pump beam.University of ManitobaFebruary 202
A comparison of the Canadian Rangers with the Canadian Army’s Primary Reserve Force
Get PDFThe Canadian Armed Forces’ (CAF) Canadian Rangers program is lauded by allies as an inventive program to provide remote Canadian communities and Arctic hamlets with Indigenous Army Reserve units. While the Canadian Rangers are a sub-component of the CAF Army Reserve, they employ a separate operation model than the Primary Reserve Forces. CAF Primary Reserve units are located in hundreds of larger communities across Canada with many part-time positions and training often occurring on weekends.
While the Primary Army Reserves and Canadian Rangers both fall under the large umbrella that is the Army Reserves, there are significant differences. A comprehensive analysis of the Canadian Rangers and Primary Reserve Force members is examined in this thesis. Both internal and external characteristics of each group are examined.
The internal factors compared include: leadership, rank structure, typical tasks, guiding documents, discipline, military professionalism, training plans, command and control structures and combat capabilities. The external characteristics compared include each group’s geographical location, recruitment demographics, and different ways of knowing. This thesis asks, why does the Government of Canada have separate Army Reserve systems with differing internal and external characteristics? What are the differences and similarities between the groups and what are the lessons learned? These are the questions this research project addresses to glean policy-informed advice for the CAF, Government of Canada, and allies.J.W. Dafoe Graduate Fellowship for Study in International RelationsOctober 202
Study on underutilized ancient wheat species for bakery utilization
No full textChanging consumer preferences have resulted in growing interest in underutilized ancient wheat species like einkorn, emmer, and spelt as they offer numerous health and ecological benefits. However, the differences in physicochemical characteristics of these grains in comparison to conventional hexaploid bread wheat results in baked products with sub-optimal quality reducing their overall utilization. Therefore, the identification and selection of ancient wheat cultivars with better end-use quality is warranted to increase value addition and utilization. In the first study, two spring cultivars of einkorn (CDC Aixe and CDC Marval), emmer (CDC Tatra and CDC Yon) and spelt (CDC Zorba and CDC Silex) grown in the Canadian prairies were selected and compared with Canada Western Red Spring (CWRS) wheat. The rheological, pasting and baking characteristics of the selected cultivars of einkorn, emmer, spelt and were compared with CWRS wheat. CDC Tatra (emmer) bread had a significantly higher specific volume (3.32 ml/g) than CWRS wholewheat bread. Significant differences in chemical composition, pasting, mixing, and baking properties were found between CWRS and ancient wheat cultivars. However, overall, the quality of ancient grain bread needed improvement. The second chapter deals with ingredient technology and process modifications to improve the end-product functionalities of ancient wheat species. Four commonly used emulsifiers were added to ancient wheat flour samples at three different concentrations. Extrusion was conducted on these ancient wheat species at three different screw speeds (100,150 and 200 RPM) to modify the functionality by the application of shear. Pasting, mixing, and thermal properties of emulsifier-treated flour and extruded flour were studied, and wholegrain bread baking was conducted by combining them with base flour. The overall volume for emulsifier-treated (50%) bread samples of einkorn and spelt was higher than base flour bread. The water absorption value of extrudate-added bread dough increased significantly. However, these treated flour additions did not improve the breadmaking attributes of emmer bread. Overall, the study provides insights into selecting cultivars for breadmaking applications and how specific emulsifier treatment and extrusion can improve end product functionalities of ancient grains.October 202
Age- and sex-associated alterations in hypothalamic mitochondrial bioenergetics and inflammatory-associated signaling in the 3xTg mouse model of Alzheimer’s disease
No full textAbstract Mitochondrial dysfunction and associated inflammatory signaling are pivotal in both aging and in Alzheimer’s disease (AD). Studies have also shown that hypothalamic function is affected in AD. The hypothalamus may be a target for AD drugs given that mitochondrial alterations are observed in the hypothalamus. This study investigated how age and sex affect mitochondrial bioenergetics and inflammatory signaling in the hypothalamic mitochondria of 3xTg and control mice at 2, 6, and 13 months, aiming to enhance our understanding of these processes in aging and AD. Parameters included oxygen consumption rates, expression levels of subunits comprising mitochondrial complexes I-V, the enzymatic activity of cytochrome c oxidase (COX), transcription factors associated with inflammation such as NF-κB, pIκB-α, Nrf2, and other inflammatory biomarkers. Hypothalamic mitochondrial dysfunction was observed in 3xTg females as early as 2 months, but no changes were detected in 3xTg males until 6 months of age. In 3xTg mice, subunit expression levels for mitochondrial complexes I-II were significantly reduced in both sexes. Significant sex-based differences in COX activity were also observed at 13 months of age, with levels being lower in females compared to males. In addition, significant sex differences were indicated in NF-κB, pIκB-α, Nrf2, and other inflammatory biomarkers at different age groups during normal aging and AD progression. These findings highlight important sex differences in hypothalamic bioenergetics and inflammation, offering insights into potential new targets for preventing and/or treating AD.Plain English summary Alzheimer’s disease (AD) is a gradual onset disorder, characterized by memory impairments. The greatest risk factor is age. In addition, almost two-thirds of Americans with AD are women, and reasons for this health disparity are unclear. While it’s true that women live longer than men, longevity alone does not explain this disparity. Interestingly, studies have also shown that hypothalamic function is affected in AD, but it appears that men are affected differently than women. The hypothalamus regulates numerous functions, including sex hormone regulation, sleep/wake cycles, and energy expenditure, to name a few. In this study, we examined how changes in energy metabolism may be different in the hypothalamus in male vs. female genetically engineered mice that model AD pathology.Highlights Hypothalamic mitochondrial dysfunction was observed in 3xTg females as early as 2 months, but no changes were detected in 3xTg males until 6 months of age. In 3xTg mice, sex-based differences were observed in the expression levels of subunits for mitochondrial complexes II and III. Significant sex-based differences in COX activity were also observed at 13 months of age, with levels being lower in females compared to males. Significant sex differences were indicated in NF-κB, pIκB-α, Nrf2, and other inflammatory biomarkers at different age groups during normal aging and AD progression
Development of boronic acid modified topoisomerase I inhibitors as covalent-binding chemotherapeutic agents
No full textIntroduction: Camptothecins are effective chemotherapeutic agents due to their ability to inhibit topoisomerase 1 (Top1), an enzyme that changes the topology of DNA through relaxation of DNA supercoils for cellular processes such as DNA replication. Through inhibition of Top1, programmed cell death can be induced in cancer cells undergoing rapid proliferation.
Covalent inhibitors are a class of drug that offer stronger receptor interactions, improved potency, selectivity, and duration of action over non-covalent drugs. We hypothesize that we can develop drug candidates using a functional boron warhead that forms an additional targeted covalent interaction with the Top1 cleavage complex, generating optimized chemotherapeutic agents for pre-clinical study.
Methods: Drug candidates were synthesized, purified by flash chromatography, and characterized by NMR and mass spectroscopy. The drug candidates underwent in vitro evaluation of cancer anti-proliferative capability and covalent mechanism of action. Cell viability (MTT/MTS) assays were performed against several cell lines after 72 h of drug exposure. Annexin-V flow cytometry was used to assess apoptotic capability of drug candidates. Covalent binding experiments were performed using washout assays and modified agarose gel-based cleavage/relaxation assays on Top1 nuclear extract and pBR322 DNA.
Results: The drug candidates displayed potent cancer growth inhibition activity with nanomolar half maximal inhibitory concentrations (IC50s) against several cancer cell lines. Several drug candidates were submitted to the National Cancer Institute 60 human tumor cell lines screen where they showed potent anti-proliferative activity (<10 nM GI50) against central nervous system type cancers. Annexin-V flow cytometry assay revealed drug candidates induce similar apoptosis and cell death scatter profiles to clinically approved Top1 inhibitors. Washout and salt reversal assays suggest potential of one of the drug candidates to resist washout and salt induced reversal of ternary complex through formation of a covalent complex with Top1.
Conclusion: The drug candidates displayed potent cancer growth inhibition activity through the formation of a ternary complex with Top1 and DNA. Washout and salt reversal assays suggest one of our candidates forms an additional covalent interaction with the Top1 through stabilization of the ternary cleavage complex.October 202
Area G and the Digging of Kom Aushim
No full textAn analysis of the early history of digging at Kom Aushim and the Museum archaeology of Karanis papyri purchased on the Egyptian antiquities market is combined with archaeological data from the University of Michigan’s excavations to locate purchased papyri in the archaeological record
Using quantitative methods to understand how dairy farmer wellbeing connects to farm management, barn design, technology, and animal welfare
Get PDFThe agricultural profession, particularly dairy farming, is known for its demanding nature, both physically and mentally. Dairy farmers encounter various challenges including long working hours, physical labour, financial pressures, and unpredictable weather conditions. My objective was to explore different farm management practices, farming factors, and the prevalence of mental and physical health issues among dairy farmers in Western Canada and Ontario. Statistical analyses included t-tests, ANOVA, and chi-squared tests to compare means with general population averages and to investigate associations between mental health scores and physical health outcomes with survey variables. The results of the survey indicated that farmers (n=115) scored significantly higher on perceived stress (P<0.001), anxiety (P<0.001), depression (P=0.04), and resilience scales (P<0.001) compared to the general population. The results also highlighted concerns regarding the physical health of dairy farmers, with the majority reporting work-related injuries and health issues. I identified significant differences when comparing mental and physical health with work-life balance, social environment and support, and specific dairy-related stressors. Farmers faced both personal and farming-related financial stressors. Surprisingly, health outcomes did not differ based on housing or milking system, management practices, farm responsibilities, or financial and transition planning variables. Therefore, dairy farmers appear to have similar well-being in different production systems, but farm finance, feed cost, weather, and workload constraints are major stressors. I then adopted a more holistic approach to cluster farmers based on their well-being and farm management. The analysis identified four distinct groups of dairy farmers based on their survey responses. It also emphasized the need for a deeper understanding of the unique challenges faced by individual farmers in their production systems. Without this understanding, there is a risk of developing intervention plans that are ineffective or inappropriate for the Canadian dairy industry. The typologies developed in this research offer a promising foundation for providing tailored support resources.October 202