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Three essays on corporate finance
No full textThe thesis consists of three essays. In the first essay, we investigate the relation between excess cash holdings and future stock returns using a sample of firms in developed markets and emerging markets. The results show a positive relation between excess cash and future returns in developed markets but not in emerging markets. In developed markets, firms with higher excess cash have higher market betas and invest more in the future. Furthermore, the positive relation between excess cash and future stock returns is driven by rising market states. In contrast, we do not find similar patterns in emerging market. Overall, the evidence suggests that excess cash holdings proxy for growth opportunities in developed markets but not in emerging markets.
In the second essay, we investigate corporate cash holdings in developed countries. This research assesses the cash difference between firms in developed Europe and the US and seeks to account for this difference. Results indicate that developed European firms hold less cash than are US firms, and this is largely explained by regional differences in intangible assets. We further find that the difference in intangible assets between developed Europe and the US is mainly driven by sector specialization. This finding supports literature that US companies outperform European firms in high R&D intensity sectors.
In the third essay, we examine the relation between corporate debt maturity and cross-sectional equity returns in non-US markets. Prior research has shown that the maturity structure of corporate debt matters in explaining the equity risk premium of US stocks. In the US, debt refinancing intensity is associated with a positive risk premium. This essay re-evaluates this relation in international stocks. We find a similar positive relation between debt refinancing intensity and equity risk premium in developed European markets but not in emerging Asian markets. In developed Europe, the positive relation is driven by firms with low levels of information asymmetry. The results are consistent with the theory that investors demand compensation for risks associated with refinancing of short-term debt, especially for firms where short-term debt plays a limited role in reducing agency risks.February 202
Genomic characterization of human traits associated with polyglutamine disease genes and modifiers
No full textBackground: Polyglutamine (polyQ) diseases, such as Huntington disease (HD) and certain spinocerebellar ataxia, are a group of severe neurodegenerative disorders caused by duplication of the glutamine codon. These conditions currently lack effective treatments, and most therapeutics in development are focused on pathogenic gene knockdown, which may have unintended consequences.
Objective: We aimed to profile polyQ disease genes to guide therapeutic interventions by identifying potential off-target effects.
Methods and Results: We performed an unbiased phenome-wide study to identify traits linked to polyQ genes by analyzing Open Targets Genetics Database data. We curated 3,095 traits associated with polyQ genes. Applying a locus-to-gene filtering threshold of 0.5 that quantifies the strength of evidence (0 to 1, higher scores signifying increased strength), we retained 215 gene associations, encompassing both disease and non-pathogenic traits, including neurological outcomes and suggesting adverse outcomes associated with gene knockdown. We further assessed the theoretical druggability of these genes and revealed that polyQ genes may not be favorable therapeutic targets suggesting the need to explore alternative rational targets such as modifiers.
We prioritized HD for further analysis as it is the most well-studied polyQ disorder, with large cohorts of affected individuals recruited for human genetic studies, therefore, providing a framework to understand other polyQ disorders. Further analysis involved fine-mapping, a technique used to pinpoint variants, of the HD onset GWAS to identify candidate variants and genes modifying disease onset. We applied a functionally informed fine-mapping strategy to refine credible sets of causal variants at significant risk regions (p < 5x10-6). We used a posterior inclusion probability filtering threshold of 0.5 to identify potential causal variants. We prioritized eight candidate variants, including five previously reported signals, and three new ones. A subset of these signals harboured missense variants associated with DNA repair genes (i.e., MLH1, MSH3, FAN1, LIG1). Notably, two new variants, rs149892574 and rs2798373, were identified as potentially modifying HD onset through changing enhancer and promoter sequences.
Conclusion: Altogether, our analysis highlights the need to consider alternative therapeutic options for polyQ disorders and further prioritizes HD onset modifiers that require functional validation and can be extended to other polyQ disorders.Natural Sciences and Engineering Research Council of Canada (Canada Research Chair: Neurogenomics, Award Number: CRC-2019-145),
Health Sciences Centre Foundation General Operating Grant (Fine-mapping of neurodegenerative disorder genomic risk loci for the prioritization of novel drug targets),
Research Manitoba (Funder Identifier: http://dx.doi.org/10.13039/100008794)October 202
Vegetative preferences and the impact of Dutch Elm Disease (Ophiostoma ulmi) on bird abundance in Winnipeg, Manitoba
No full textSince 2016, Winnipeg’s urban forest has lost more than 33,000 American elm (Ulmus americanus) providing habitat to urban birds due to Dutch Elm Disease (DED) (Ophiostoma ulmi) (Trees Winnipeg, 2021). However, the presence of DED in a migratory and breeding stopover site may increase insect abundance for insectivores and urban bird species, such as resident woodpeckers (spp.), warblers (Parulidae spp.), and other insect-eating birds that forage and nest in dead elm trees (Nicholls, 1994). The research investigates the impact of DED and its potential benefit on bird populations, as well as their vegetative preferences by recording 45 bird abundance point counts conducted across 18 neighbourhoods in Winnipeg during spring migration in 2022 and 2023. Bird abundance and vegetative composition was recorded in 50-m² circular plots next to a focal elm tree on public property that was either healthy, diseased with DED, or sites where elms had been recently removed due to DED to assess the potential positive or negative effects of DED on the bird population’s usage of an urban habitat. Results indicated that year-round residents, as generalists in the urban environment, benefit from DED. However, breeding migrant birds, with their more specialized habitat requirements, are significantly and negatively impacted by DED. The fact that breeding migrants and year-round residents were significantly less abundant in sites where elms had been recently removed underscores the urgent need for effective DED management in Winnipeg to preserve elms as bird habitat. Birds were most abundant near non-native deciduous shrubs, coniferous trees and shrubs, and riparian areas like riverbanks and greenspaces. This highlights the importance of restoring riverbanks, cultivating higher diversity in the urban forest, and increasing connectivity between natural areas in Winnipeg.The Connie Holland Bird Study Fund Award
The Winnipeg Foundation
http://dx.doi.org/10.13039/100014509
Manitoba Big Game Trophy Association Bursary Fund
Manitoba Big Game Trophy Association
https://www.brandonu.ca/environmental-science/files/2012/02/MB-Big-Game-Trophy-Bursary-application.pdfOctober 202
Highly efficient Yb-ion-doped lasers pumped at 946 nm by a compact Nd:YAG laser
No full textThe development of efficient ultrafast laser sources based on Yb-doped crystals is very important for a variety of optical applications such as nonlinear spectroscopy, nonlinear microscopy, telecommunications etc. A powerful and high beam quality (near diffraction limited: M2~1) pump laser is desirable to mitigate the effect of reabsorption loss that Yb-doped crystals exhibit and realize highly efficient operation in both continuous-wave (CW) and pulsed domains. Unfortunately, there are no commercially available laser diodes that can provide both high beam quality and high output power (>1 W) simultaneously. This thesis presents the development of a powerful and high beam quality pump laser and then utilizes this pump laser to demonstrate the efficient operation of Yb:YAG laser in CW domain and Yb:KGW laser in both the CW and pulsed domains.
In the first part of the thesis, a high-power compact CW Nd:YAG laser was built with greatly improved beam quality operating at 946 nm. A maximum output power of 9.98 W with beam quality factor M2 ~ 5 was obtained. I also demonstrated a highly efficient and tunable CW Yb:YAG laser pumped by the developed Nd:YAG laser. The maximum CW output power of 4.37 W was obtained at 1030 nm with optical-to-optical efficiency of 70% with respect to the absorbed pump power. Wavelength tuning of Yb:YAG laser was then explored due to metrological applications such as references for high-resolution spectroscopy or dimensional metrology. The laser produced a continuously tunable operation over 100 nm from 1000 nm to 1100 nm. This is the most tunable laser among bulk crystalline Yb:YAG solid-state lasers. Due to the increasing interest in dual-wavelength (DW) operation for the use as an optical source for terahertz (THz) radiation, this thesis also gave a demonstration of DW Yb:YAG laser operation. This is the first demonstration of DW operation of Yb:YAG laser pumped by a Nd:YAG laser at 946 nm.
The latter part of the thesis concentrated on developing a highly efficient ultrashort pulse Yb:KGW laser oscillator pumped by the Nd:YAG laser. In the mode-locked regime, 175 fs duration pulses centered around 1025 nm were generated at a repetition rate of 54.6 MHz with a total average output power of up to 1.1 W, corresponding to optical-to-optical efficiency of 34.8% with respect to the absorbed pump power. In the CW regime, the maximum output power of 3.7 W was obtained for an absorbed power of 5.13 W that represents optical-to-optical efficiency of 72.12%. Furthermore, the tunability of Yb:KGW laser was studied and the laser produced a continuously tunable operation of 90 nm from 990 nm to 1080 nm. This is the most tunable and efficient laser in the CW regime among bulk crystalline Yb:KGW solid-state lasers.February 202
Exploring the feasibility of mycelium-based cups as a sustainable alternative to single-use beverage cups
No full textDisposable paper (DP) cups, a staple in on-the-go beverage culture, contribute to environmental challenges due to their non-biodegradable polyethylene (PE) liners. This research presents an eco-friendly alternative by harnessing fungal mycelium combined with North American wetland biomass. The study evaluates three fungal species—Ganoderma lucidum, Pleurotus ostreatus, and Polyporus squamosus—cultivated on canola straw (Brassica napus L.) and cattail substrates (Typha latifolia) to produce mycelium composite materials. Among these, Ganoderma lucidum demonstrated superior mycelial growth and structural integrity when paired with cattail substrate over a 14-day period. Initial growth assessment was conducted using Potato Dextrose Agar (PDA), with further optimization through Yeast Extract Peptone Dextrose Broth (YEPDB) liquid media. The research explored the production of compostable coffee cups and mycelium sheets using a 3D poly-lactic acid (PLA) mold and aluminum foil, respectively. Mycelium composites were harvested at two growth intervals (2 weeks and 4 weeks) and analyzed for their morphological, chemical, thermo-mechanical, crystallinity, thermodynamic, and mechanical properties. The resulting composites exhibited notable thermal stability exceeding 267°C, low thermal conductivity (0.03-0.04 Wm⁻¹K⁻¹), and inherent hydrophobicity with a water contact angle surpassing at 100°. However, the mechanical properties, such as Young's modulus, were significantly lower than those of commercial coffee cup paper, with values of 11.27 MPa and 80.91 MPa for the 2-week and 4-week samples, respectively, compared to 1349.35 MPa for standard coffee cup paper. These findings demonstrate that cattail can serve as a viable substrate for producing mycelium-based bio-composites, suitable for applications requiring thermal stability and hydrophobicity.October 202
Effects of polysaccharide iron complexes on growth, gut health, and gut microbiota in nursery pigs raised under different sanitary conditions
No full textThis study evaluated the effect of different iron sources, including iron polysaccharide complexes
(SQM®.iron) and ferrous sulfate (FS) on growth performance, gut health, pathogenic bacteria load,
colon microbiota, and fecal iron concentration in nursery pigs. A total of 320 weaned pigs were
randomly assigned to four treatments arranged in a 2 × 2 factorial design, with the factors being
sanitation conditions (clean vs. dirty) and iron sources (SQM® iron vs. FS, each at 100 mg iron/kg)
to give 8 pens (10 piglets per pen) per treatment. Pigs were fed their respective diets in two phases
over a 28-d period. Fecal scores, body weight (BW), and feed intake were recorded weekly. Iron
content, gene expression of butyryl-CoA:acetate CoA-transferase and bisulfite reductase, and
pathogenic bacteria quantification were determined in fresh fecal samples collected on d 0, d 14,
and d 21. On d 28, one pig randomly selected from each pen was euthanized to sample colon
digesta for 16S rRNA analysis and sample jejunal tissue and serum for gut integrity and
permeability analysis. Overall, SQM® iron resulted in higher average daily gain (ADG) from d 0
to14 and average daily feed intake (ADFI) from d 0 to 28 (P < 0.05). SQM® iron resulted in higher
fecal iron at d 21 and improved fecal scores at d 27 (P < 0.05). Dietary iron treatments did not
significantly affect gastrointestinal integrity and permeability in jejunum and did not alter fecal
microbiota composition on d 28. In conclusion, substituting 100 mg/kg added iron as ferrous
sulfate with equal concentration of SQM® iron improved ADG in the phase 1 (d 0 to 14) and
overall ADFI (d 0 to 28) in weaned pigs.October 202
An analytical framework to examine and describe people’s expectations of robots
No full textWe engaged with the problem of expectation discrepancy in human-robot interaction: a known challenge in which the expectations people form when interacting with a social robot may not align with its actual capabilities. This misalignment, an expectation discrepancy, can disappoint users and hinder interaction. While research has proposed ways to mitigate expectation discrepancy, designers lack a systematic approach to analyzing and describing expectations people form of their robot. A more rigorous theoretical framework is a necessary step towards designing robots to purposefully engineering desired expectations. We consulted theories and models from psychology and sociology on expectations between people, and conducted a survey of expectations in human-robot interactions. Through this we developed an analytical framework consisting of a novel model of the cognitive process of human-robot expectation formation, as well as a taxonomy for classifying the types of expectations they form. We finally propose preliminary methods for designers to use this framework as a tool to support systematic analysis of how and why people form expectations of a given robot and what those expectations may be. Such understanding can empower designers with greater control over people’s expectations, enabling them to combat problems of expectation discrepancy.October 202
Reduced fermentation of dietary fibers by gut microbiota results in increased unfermented β-fructans in the gut and subsequent induction of organ-specific damage in diseases of the gut-brain axis
No full textGut microbes ferment dietary fibers, producing beneficial short-chain fatty acids (SCFAs). Often, individuals with inflammatory bowel disease (IBD) and multiple sclerosis (MS) have altered gut microbiota, reduced SCFAs, and fiber sensitivity. The Armstrong lab demonstrated that unfermented β-fructan fibers induce inflammation via TLR2 and the NLRP3 inflammasome in IBD. Chronic inflammation can promote colorectal cancer (CRC), suggesting that diet-induced inflammation may promote IBD progression to CRC. Similar changes in the gut microbiome, SCFAs, and TLR2 are involved in gut-brain axis diseases, suggesting that fiber-induced inflammation may impact other autoimmune diseases. Therefore, I hypothesized that unfermented β-fructans promote inflammatory processes related to IBD progression to IBD-CRC and affect other gut-brain axis diseases, specifically MS.
To examine tumorigenic responses, cell migration (scratch wound assay with Mitomycin C) and barrier integrity (TEER) were examined in human gut epithelial cells (Caco2, T84) treated with β-fructans. Intestinal biopsies (non-IBD/IBD) were cultured ex vivo with β-fructans. Changes in IBD-CRC markers (p53, villin, axin2, NLRP3) were examined with TLR2 (β-fructan receptor) using microscopy. Barrier integrity and cell migration were not impacted by β-fructans, but an inability to polarize cells affected TEER measurements. Pro-tumorigenic markers were positively associated with TLR2 in colonic biopsies.
To examine how unfermented β-fructans impact the gut-brain axis beyond IBD, we used the experimental autoimmune encephalomyelitis (EAE) mouse model of MS in germ-free (unable to ferment) mice. Mice began a β-fructan (5%) or control (5% cellulose) diet at day 14 (symptom onset). EAE scores and weight were recorded daily. Tissues were examined for gut damage and demyelinating lesions (H&E, Luxol Fast Blue-Hematoxylin). EAE mice consuming β-fructan displayed worsened CNS symptoms following symptom peak (day 20-28; P<0.05) with increased CNS demyelinating lesions in the brain and spine (P<0.001). While dietary fibers form interactions in the gut, EAE mice had no gut damage.
This suggests that unfermented β-fructan promotes disease-specific organ damage in the gut-brain axis, such as IBD progression to IBD-CRC or CNS damage in an MS mouse model. Gut microbiota changes and reduced fermentation increase unfermented fiber, likely altering the immune system (TLR2 pathways), leading to detrimental effects of β-fructan in the gut-brain axis.2.
Funder name: MS Canada
Funder identifier: http://dx.doi.org/10.13039/501100000261
Award title: Catalyst Grant
Award number: MS1030817
Award URL: https://mscanada.ca/
3.
UM start-up grantOctober 202
Study of conformational analysis, internal dynamics and non-covalent interactions of chalcogen-bridged compounds (oxygen vs sulfur) by rotational spectroscopy and computational chemistry
No full textConformational analysis is a fundamental tool for assessing the three-dimensional spatial arrangements, energies, and stability of conformers influenced by intermolecular and intramolecular interactions. Rotational spectroscopy plays a crucial role in determining spectroscopic parameters by identifying their spectral fingerprints, while high-level quantum chemical calculations aid in the assignment of spectra and provide insights into conformational preferences and internal dynamics. In this thesis, we investigated the effect of different organic fragments on the conformational landscape of chalcogen-bridged compounds (oxygen vs sulfur). As previous microwave spectroscopic studies predominantly centered around small molecules containing O and S, our objective is to bridge this research void by analyzing relatively large and flexible molecules. We observed drastic differences in the conformational equilibria when transitioning from O to S bridged compounds, involving diallyl ether, diallyl sulfide, allyl ethyl ether, allyl ethyl sulfide, ethyl vinyl ether, ethyl vinyl sulfide, propyl vinyl ether, propyl vinyl sulfide, butyl vinyl ether, butyl vinyl sulfide. Additionally, we explored the effects of microsolvation through diallyl ether-water and diallyl sulfide-water complexes. A general trend emerged, indicating that the O-bridged compounds exhibit a competitive and rich conformational landscape in the presence of partially unsaturated side chains. However, the inclusion of saturated side chains with an increase in their length led to conformers being more close in terms of relative energies and to a greater number of conformers in S-bridged compounds compared to oxygen ones. Non-covalent interaction, natural bond orbital, quantum theory of atoms in molecules, and symmetry-adapted perturbation theory calculations, revealed the pivotal role of interactions involving the lone pairs of the central chalcogen atom (oxygen or sulfur) and the organic fragment in governing conformational preference and energy ordering. We also observed complex splitting patterns attributed to methyl internal rotations in molecules featuring a methyl group. The results presented here lay a solid foundation for future studies aimed at advancing the development and modeling of chemical bonds, dynamics, and reactivity of organochalogens and main group compounds.Department of Chemistry, UOM
Faculty of Graduate Studies, UOM
GETS program, UOMFebruary 202
Doing gender inclusive and affirmingr practices in undergraduate nursing education: Preliminary findings from a scoping review
No full textHealth care professionals are required by their codes of ethics to provide equitable care for all (1–4). Often, historically, persistently, and systematically marginalized groups are denied equitable health care (5). One contributing factor is inadequate health professional education concerning equity and social accountability (6). While health professional education has improved its formal curricula regarding health equity, the informal (relationships and interactions) and hidden curricula (the culture and values of a profession and/or institution) are lesser known (7,8). Preliminary findings from a scoping review (n=40), being conducted as part of my thesis work, shows that most efforts to advance gender inclusive and affirming (GIA) nursing education are in the formal curricula, with minimal efforts to address the informal and much less so the hidden curricula. GIA practices, like gender-affirming care, benefit people of all genders, however, GIA practices go a step further to create GIA spaces that transcend health care into all spaces (9,10). As such, our scoping review is mapping GIA practices across the curriculum within nursing schools in Canada and the USA (11). The proposed poster will outline initial findings of how schools are doing GIA practices in undergraduate nursing education, including outlining gaps and recommendations. FGS attendees who visit this poster will be invited to engage in a dialogue about what GIA health care means to them and how they want to see GIA enacted in health care professional education and health care practices.
References
1. Canadian Medical Association. CMA Code of Ethics and Professionalism. Can Med Assoc [Internet]. 2018;1–6. Available from: http://www.ncbi.nlm.nih.gov/pubmed/20311772%0Ahttp://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=PMC1930662
2. Canadian Nurses Association. Code of ethics for registered nurses. 2017; Available from: www.nanb.nb.ca/media/resource/Code_of_Ethics-2017-E.pdf
3. Canadian Physiotherapy Association. Code of ethical conduct [Internet]. 2020 p. 1. Available from: https://physiotherapy.ca/cpa-code-ethics
4. Canadian Dental Association. CDA principles of ethics [Internet]. 2015. Available from: https://www.cda-adc.ca/en/about/ethics/
5. McGibbon E, editor. Oppression: A social determinant of health. 2nd ed. Fernwood Publishing; 2021.
6. Ventres W, Boelen C, Haq C. Time for action: key considerations for implementing social accountability in the education of health professionals. Adv Health Sci Educ [Internet]. 2018 Oct [cited 2023 Sep 19];23(4):853–62. Available from: http://link.springer.com/10.1007/s10459-017-9792-z
7. Raso A, Marchetti A, D’Angelo D, Albanesi B, Garrino L, Dimonte V, et al. The hidden curriculum in nursing education: a scoping study. Med Educ [Internet]. 2019 [cited 2023 Jan 27];53(10):989–1002. Available from: https://onlinelibrary.wiley.com/doi/abs/10.1111/medu.13911
8. Hafferty FW. Beyond curriculum reform: Confronting medicine’s hidden curriculum. Acad Med [Internet]. 1998;73(4):403–7. Available from: https://oce-ovid-com.uml.idm.oclc.org/article/00001888-199804000-00013/HTML
9. Rivera D. Care without assumption: the perceptions of transgender persons regarding their experiences with nursing care. Int J Hum Caring [Internet]. 2019 Jul [cited 2022 Nov 20];23(3):242–53. Available from: http://uml.idm.oclc.org/login?url=https://search.ebscohost.com/login.aspx?direct=true&db=c8h&AN=139213252&site=ehost-live
10. Soled KRS, Clark KD, Altman MR, Bosse JD, Thompson RA, Squires A, et al. Changing language, changes lives: Learning the lexicon of LGBTQ+ health equity. Res Nurs Health [Internet]. 2022 [cited 2023 Feb 7];45(6):621–32. Available from: https://onlinelibrary.wiley.com/doi/abs/10.1002/nur.22274
11. Crawford J, Schultz ASH, Linton J, Kramer M, Ristock J. Gender-affirming care in undergraduate nursing education: a scoping review protocol. BMJ Open [Internet]. 2023;13(3):e070576. Available from: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85150263559&doi=10.1136%2fbmjopen-2022-070576&partnerID=40&md5=95d1b466e7f84e3dc1051f2728a03d32Canadian Nurses Foundation (Tylenol® Fund to Advance Diversity in Nursing and Health Equity Research Scholarship) Scholar
University of Manitoba’s College of Nursing Endowment Fund Graduate Student Research Gran