30921 research outputs found
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The use of floral enhancements to support beneficial insects in prairie agroecosystems
No full textInsects worldwide are in decline, with strong evidence that climate change and agricultural practices are to blame. Pesticides, tillage, and land conversion all negatively affect insect community structure. Recent policy changes have not proved effective enough to conserve insects. Understanding long-term techniques to manage and conserve insects in agricultural settings is necessary to maintain the ecosystem services they provide. Floral strips have proven effective in perennial cropping systems, but it is unclear if these practices will prove effective in annual systems. I installed fifteen floral strips adjacent to annual crop fields, and five hay fields planted with a pollinator enhanced seed mix in Manitoba, Canada. I measured these sites for multiple years to determine beneficial insect responses to the enhancement, farm management techniques, and the surrounding landscape. Insect functional traits are investigated and discussed.
I found that floral strips generally increased capture rates of ground beetles (Coleoptera: Carabidae), and bees (Hymenoptera: Apoidea), but not syrphids (Diptera: Syrphidae). Bees spilled over from the strips into the adjacent annual crop fields, but I did not observe this trend for ground beetles or syrphids. Ground beetles responded to the landscape at small (500 m) scales and were positively associated with habitat connectivity. Syrphids were positively associated with landscapes with continuous patches of landcover at small (500 m) scales. Bees responded at larger (3 km) scales and were positively associated with forb cover and landscape diversity. Floral strips supported the reproduction of bees. I found more stem-nests with a higher dietary diversity at strip sites. Additionally, 23.5% of offspring provisions may have come from the strips. Bee communities differed based on vegetation management. Enhanced hay fields supported fewer bees than grazed or natural sites, and captured primarily honey bees. Grazed fields supported primarily ground-nesting, solitary bees, while natural sites supported more hive-nesting, polylectic bees. Low capture rates of bees in hay fields could be due to their lack of floral diversity, as > 99 % of ground cover was alfalfa. I have shown that floral enhancements can be an effective tool for managing insects in annual cropping systems. Recommendations for their use in Manitoba are discussed.Western Grains Research Foundation
Natural Sciences and Engineering Council of Canada
Mary and John Dueck
Prairie Improvement NetworkFebruary 202
Interrogating mainstream news media’s re-presentation of the ‘Parental Rights’ movement: neoliberal influences and the imposed moral panic of gender
No full textIn recent years, there has been an upward trend in Canadian mainstream news media’s coverage of what is colloquially coined the ‘Parental Rights Movement’. As the movement advances false narratives about children's rights, gender and sexuality, and teachers, it is important to consider how the mainstream media’s coverage may legitimize some of these views. Using Critical Discourse Analysis (CDA) (Fairclough, 2010; Roger, 2004) this research considers the following overarching question: In what ways has the 'parental rights' movement been framed in Canadian mainstream media outlets? Specifically:
How have the roles and relationships between students/parents/teachers been framed by the mainstream media’s coverage of 'parental rights'?
How has the purpose of public education been framed through this coverage?
How is gender and sexuality positioned within this coverage?
The 'parental rights' movement uses tactics of moral panic that leverages social anxieties, effectively mobilizing policy to increase surveillance and governance (Fowler & Mountz, 2024). CDA places language use on display in order to reveal how particular views are normalized and condoned. This study is crucial as media re-presentations cannot be disentangled from public perceptions (Buckingham, 2019; Hoechsmann & Poyntz, 2012; Kellner & Share, 2019). In line with Giroux's (2019) concept of public pedagogy, popular media—including Hollywood films, video games, social media, and mainstream news—play a significant role in shaping societal understandings. These media re-presentations not only normalize and legitimize certain views but also impact the livability and grievability of people's lives (Butler, 2010).October 202
More on the Homeric Papyri from Karanis
No full textA reassessment of the published Homeric papyri from the village of Karanis, located in Graeco-Roman Egypt's Fayum region. The paper reassesses the palaeography of the papyri, but adds new contextualizing analyses based on archaeological legacy data from the University of Michigan's 1924–1935 excavations at the site. It demonstrates that the papyrological and archaeological evidence do not typically map well onto one another
The Protagonist
No full textThis thesis centers on my original painting and script-based project, The Protagonist, comprising The Protagonist paintings and The Protagonist script, and explores how painting, as a symbolic and non-linear narrative medium, can reveal the construction of subjectivity within personal memory. I argue that language often falls short in expressing the emotional distance between memory and identity, whereas visual language offers a more immediate and intuitive mode of articulation. Departing from conventional text-based narrative structures, this research highlights the structural role of painting within the context of visual culture, emphasizing its materiality, sensory engagement, and unique modes of spectatorship. The first part of the thesis discusses the material distinctions and aesthetic characteristics of different painting media in The Protagonist paintings, alongside a reflection on how these choices correspond to The Protagonist script. The theoretical framework draws upon Paul Ricoeur’s concept of the narrative structure of memory, W. J. T. Mitchell’s analysis of image and script relations, and foundational ideas from Stuart Hall and Michel Foucault regarding identity, power, and visuality. These perspectives offer a multi-dimensional lens through which to examine the interplay of imagery, political landscapes, and personal development in The Protagonist.October 202
Excited-state manipulation through ligand design: exploring the impact of rigidity and ligand field strength in phenanthridine based ligands
No full textVarious aspects of ligand design are presented and the consequent impact on photophysical properties, both in the excited state and ground state, are explored. With a desire to develop complexes for photochemical applications, this thesis focuses on bridging facets of ligand design with their influence on the excited state manifold and ground state electronics, in an effort to identify favourable ligand features. The overall theme of this thesis is how hybrid ligands, combining a strong-field ligand with a good π-acceptor, influence the isolable excited states either for luminescent or photoreactivity purposes. The first three results chapters describe the synthesis of new transition metal complexes, followed by a comprehensive physical study of the electronic structure and/or excited state physical properties. The final experimental chapter describes probing the applicability in photophysical reactions, where a myriad of reactions were attempted using various potential photocatalysts.
Establishing the need for strong field ligands was accomplished using a developed weak field ligand. Transitioning to stronger field ligands was executed by combining phenanthridine with a cyclometallating group, leading to enhanced emission properties. Several important ligand characteristics were brought to our attention from this work: how intramolecular rigidity is beneficial to photophysical properties, and the importance of the position phenanthridine is functionalized on. Curious to the bias these properties may impart on 3d transition metals, a ligand was designed to maximize these qualities while being able to chelate the lighter transition metals. The heightened rigidity and strong ligand field combined with phenanthridine all worked synergistically to isolate the longest triplet metal-centred excited state identified in an Fe(II) complex by an approximate 200-fold increase. With a variety of complexes and their photophysical properties established, the feasibility of photoreactivity was explored by attempting both electron and energy transfer reactions. These reactions were successful with triplet metal-to-ligand charge-transfer excited states engendered by heavier transition metals bearing weak field ligands, high spin metal-centred excited states from a weak field Fe(II) complex, and a triplet metal-centred state in a rigid Fe(II) complex with strong field ligands.October 202
Racialized immigrant and international graduate students' sense of belonging, safe space, and inclusive pedagogy
No full textThis study explores racialized immigrant and racialized international students’ experiences of belonging, safety, and inclusive pedagogy in Higher Education (HE). Conducted at the University of Manitoba, a Western Canadian research university, the study investigates how these students perceive their social and academic environment, the factors influencing their sense of belonging, and how their experiences inform Equity, Diversity, and Inclusion (EDI) practices. Guided by a qualitative phenomenological case study approach within a social constructivist framework, the research employed in-depth semi-structured interviews with 13 participants. These interviews captured lived experiences and perspectives related to intersecting identities of race, gender, and sexual orientation. Thematic analysis, primarily informed by critical race theory (CRT), revealed recurring themes of exclusion, marginalization, microaggression, resilience, and counter-stories. Participants frequently experienced marginalization in academic and social contexts, highlighting Eurocentrism in curricula, challenges in cultivating safe classroom spaces, and institutional struggles to integrate the contributions of minoritized students. Despite these barriers, participants demonstrated resilience through coping strategies such as seeking peer support, navigating institutional power dynamics, and developing spaces of agency. The study underscores the need for systemic change in HE to address structural inequities that impede genuine inclusion. The study concludes with implications for practice around institutional culture, mentorship, and spaces of agency. Findings contribute to the broader EDI discourse by exposing the gap between institutional rhetoric and the lived realities of racialized immigrant and international students, advocating for transformative strategies to foster authentic belonging in academic environments.October 202
Examination of securities regulation in Canada
No full textSecurities regulators are entities responsible for supervising and regulating financial and securities markets within a designated region. Their primary role is to uphold fair and transparent trading practices, safeguard investors, and preserve the overall integrity of the financial system. This thesis examines securities regulation in Canada. It provides a historical overview and analysis of Canada’s provincial securities regulation and model, advantages, effectiveness, challenges and limitations of the decentralized regulatory approach, and a comparative analysis of the United States Securities and Exchange Commission. The doctrinal methodology was adopted for the study, as the work examined relevant court decisions, supported with the use of secondary sources of data with respect to both arguments for and against the use of a single regulator in Canada, and the constitutional and practical impediments that need to be curbed. The study finds that the Canadian provincial regulatory model offers flexibility, allowing each province to tailor regulations to its specific economic and market conditions. This localized approach fosters innovation, competition, and responsiveness to regional needs while maintaining regulatory diversity. However, the decentralized system also creates challenges, such as regulatory fragmentation, inefficiencies, and difficulties in establishing a cohesive national strategy. The research argues that this model hampers Canada's ability to respond uniformly to systemic risks and adapt to the evolving global financial landscape. Centralized models like the U.S. SEC enable faster, coordinated responses during financial crisis, though they may struggle with localized market issues. While Canada’s system allows for tailored regulations, the inconsistencies across provinces complicate compliance and may weaken investor confidence. The research supports adopting a more centralized approach in Canada, recommending improved inter-provincial coordination, standardized regulations, and technological innovation to enhance regulatory efficiency and systemic risk management.University of Manitoba
International Graduate Student Entrance ScholarshipOctober 202
Multiple-Reflection Time-of-Flight Mass-Spectrometry: Not just for high precision mass measurement
No full textMultiple-Reflection Time-Of-Flight Mass Spectrometers (MR-TOF-MS) are a relatively new tool that has quickly become a standard instrument for high precision mass measurements in nuclear physics. The TRIUMF’s Ion Trap for Atomic and Nuclear science (TITAN) MR-TOF-MS and a new technique of “post re-trapping stable calibrant beam merging” is described. The TITAN MR-TOF-MS is used for high precision mass measurements of 51−54 K, improving the mass uncertainties in all cases and providing a first time direct mass measurement of 54 K. The improved mass uncertainties provide evidence for the theorized N = 34 subshell closure below Ca on the nuclear chart. The mass measurements are used to compute the empirical shell gap and empirical energy gap in potassium isotopes around N = 34. This is compared to theory to strengthen the argument for an N = 34 subshell closure.
The capabilities of the TITAN MR-TOF-MS are extended through the development of novel techniques for half-life measurement of short-lived radioactive nuclides. The half-life uncertainty of the isotope 54 K is improved through an approach we call “mass tagged β-decays”. This work also presents the first experimentally determined bounds on the n-neutron-delayed β-decay probabilities in 54 K. Half-life measurements of 180−182Yb are made through the production and subsequent decay of a “re-trapping purified” radioactive source. This represents the first half-life measurements in 181 Yb and 182 Yb, demonstrating the potential of this new technique for measuring half-lives of lanthanide isotopes to elucidate nuclear structure and improve astrophysical isotope production simulations. Finally, a set of beam composition measurements for characterization of a new isotope separation online (ISOL) rare isotope production target are presented.October 202
Nutritional strategies for optimizing canola meal utilization in sow diets
No full textThe objective of this research was to optimize the use of canola meal in gestating and lactating sow diets to fully replace soybean meal without causing adverse effects on reproductive performance or piglet outcomes. In manuscript I, the effects of including 300 g/kg solvent-extracted canola meal (SCM) in late-gestation and lactation diets, with or without Saccharomyces cerevisiae product supplementation, on sow and litter performance were evaluated. Results showed that the 300 g/kg SCM-containing diet had no effect on sow or litter growth performance but compared to the control diet, reduced the apparent total tract digestibility of energy, dry matter, and crude protein in gestating sows. Lactating sows fed the canola meal-containing diet exhibited improved digestibility of NDF, and Saccharomyces cerevisiae product supplementation increased the digestibility of calcium and phosphorus. Additionally, milk fat content at weaning was higher in sows fed the canola meal supplemented with Saccharomyces cerevisiae product, demonstrating that probiotic supplementation can enhance nutrient digestibility and milk composition in canola meal-based diets. In manuscript II, the effects of including 300 g/kg SCM and expeller-extracted canola meal (ECM) with or without Saccharomyces cerevisiae product supplementation on sow and litter performance and microbiome were evaluated. Results showed that ECM diets reduced sow body weight post-farrowing and decreased crude protein digestibility in gestating sows, while Saccharomyces cerevisiae product supplementation improved nutrient digestibility and mitigated the negative effects of ECM. In addition, SCM diets did not adversely affect sow performance, and probiotics increased milk fat content on d 19 post-farrowing. Thus, SCM can replace 300 g/kg soybean meal in sow diets without adverse effects on sow reproductive performance, while ECM inclusion may require Saccharomyces cerevisiae product supplementation to ensure optimal performance. In manuscript III, the study aimed to evaluate the long-term effects of SCM inclusion as the main protein source in gestation and lactation diets on sow and litter performance over two reproductive cycles. Results showed that sow body weight and backfat thickness were unaffected by diet but varied between cycles, with greater body weight and backfat thickness observed in the second cycle. Litter performance, including weight and size, was unaffected by dietary treatment, though litter weights at birth and after cross-fostering were higher in the second cycle. The inclusion of canola meal did not adversely affect colostrum or milk composition, serum metabolites, or nutrient digestibility, demonstrating that canola meal can replace soybean meal without compromising sow or litter performance over multiple parities.October 202
Socio-economic inequalities in all-cause mortality during the COVID-19 period in north-western Tanzania, 2018–2021
No full textAbstract Background Evidence suggests that the COVID-19 pandemic has exacerbated social and demographic inequalities in the communities through pathways of unequal exposure, vulnerability, and susceptibility. In Tanzania, evidence on COVID-19-related mortality is limited to health facility data, with little to no information on the mortality patterns in the general population. This study assessed sociodemographic inequalities in all-cause mortality during the COVID-19 period in north-western Tanzania. Methods We utilized available longitudinal data from the Magu Health and Demographic Surveillance System (HDSS) from January 2018 to December 2021. We compared the crude death rates between subgroups of age, sex, area of residence, and wealth index for a period before (2018/2019) and during (2020/2021) the COVID-19 pandemic. To quantify how mortality risk varies across the subgroups we fitted a Cox proportional hazard model with an interaction of the COVID-19 period. Results Overall mortality declined from 5.9 in 2018/2019 to 5.4 and 5.5 deaths per 1000 person-years in 2020 and 2021, respectively. We observed an increase in differences in crude death rates by age groups, area of residence, and wealth quintiles during the COVID-19 period. In the Cox proportional hazards model, compared to adults aged 15–49, we observed greater mortality risk in children under five (AHR:2.9; 95%CI: 2.2–3.9), older individuals aged 50–64 years (AHR:3.02; 95%CI:2.11–4.33) and 65 + (AHR:18.65; 95%CI:14.28–24.35) during COVID-19 period. Males were also at greater risk of death compared to females (AHR:1.30; 95%CI:1.06–1.59). Conclusion Despite the overall mortality decline during the pandemic, we observed an increased risk of mortality among vulnerable subgroups (aged 60 years) in the population. This highlights the need to take into account vulnerable subpopulations when addressing major public health issues in communities