Digital Commons Network^™

Evaluating The Risk Posed By Gadolinium In The Grand River Watershed, Johann Memmel

Theses and Dissertations (Comprehensive)

Gadolinium (Gd) is a rare earth element (REE), primarily used in contrast agents for magnetic resonance imaging (MRI), with additional applications in metallurgy, phosphors, neutron shielding, and other niche applications. Both Gd and Gd-based contrast agents (GBCAs, the form used for MRIs) have been detected downstream of wastewater effluent discharges and there is currently little research into the risk this poses to aquatic ecosystems. This study investigated the potential environmental risks of Gd and GBCAs using the Grand River watershed (GRW) in southwestern Ontario as a model ecosystem due to it containing a variety of land uses (urban, industrial, agricultural) …

Coordination Chemistry Using Strategic Design Of Ligands For Switchable Properties, Delara Joekar

Theses and Dissertations (Comprehensive)

Coordination-driven self-assemblies are multifunctional molecular systems that provide an efficient method for miniaturization towards functional devices with diverse applications. Herein, the synthesis of novel pyrazole-based ligands suitable for construction of coordination assemblies is reported. These were designed using a strategy that incorporates the presence of both cationic and anionic coordination sites, and a third site for further functionalization. This design strategy has been used because there is still a knowledge gap for controlling the directionality of weak molecular forces in the presence of stronger competing forces. The structural characterization of these ligands, their Hirshfeld surface analysis, and select coordination complexes …

The Prevalence And Consequences Of Gender-Based Violence Among Trans And Non-Binary University Students In Ontario, Jia Qing Wilson-Yang

Theses and Dissertations (Comprehensive)

Community studies documenting gender-based violence (GBV) experienced by trans and non-binary (TNB) people often find differences in prevalence across TNB subgroups. Studies of TNB university students tend to treat them as a homogenous group, thus gender differences in terms of subgroups are unknown. Using data collected from TNB Ontario university students, I examined the prevalence and impacts of GBV across three TNB subgroups (trans man spectrum, trans women spectrum, and gender queer/non-binary). Specifically, reflecting subtle and overt forms of GBV, among each subgroup I explored the frequency of trans environmental microaggressions, trans interpersonal microaggressions, and victimization, and their relationship with …

The Effects Of Warmer Temperatures On The Physiology Of Invasive Sea Lamprey And Imperiled Populations Of Lake Sturgeon In The Laurentian Great Lakes, Milica Koledin

Theses and Dissertations (Comprehensive)

Invasive sea lamprey (Petromyzon marinus) contributed to massive declines in fisheries in the Laurentian Great Lakes due to their parasitism of large-bodied salmonid fishes in the 20^th century. Chemical control measures, which involve the application of 3-trifluoromethyl-4-nitrophenol (TFM) into rivers containing larval sea lamprey, were successfully implemented approximately 60 years ago to control populations. Recently, however, it was discovered that TFM tolerance increases in sea lamprey with a rise in temperature for reasons which are incompletely understood. Nor is it understood how sea lamprey will respond to warmer temperatures due to climate change, which could affect their …

Erwinia Amylovora Phage Therapy: Biocontrol Formulation, Receptor Identification, Resistance Mechanisms, Nassereldin Ibrahim

Theses and Dissertations (Comprehensive)

Fire blight is known as a disease of Rosaceae and it displays infection symptoms in about 200 species in 40 rosaceous genera. The most economically important crops that are affected by fire blight are apples and pears. Fire blight can cause severe outbreaks and a single fire blight outbreak can disrupt orchard production for years. The bacterium that causes this disease is indigenous in North America, and according to Statistics Canada, economic losses in apples and pears were valued at an estimated $4 million in 2005, which is approximately 5% of the total production. In addition, production costs can increase …

Impacts Of Environmental Stressors On Mummichog (Fundulus Heteroclitus) Growth And The Gh-Igf1 Pathway Using A Laboratory Bioassay, Olena Kuntyj

Theses and Dissertations (Comprehensive)

Using a flow-through laboratory bioassay, experiments investigated the effects of limited feeding, increased temperature, ammonium chloride (NH₄Cl), and 17α-ethinylestradiol (EE₂) on juvenile mummichog (Fundulus heteroclitus) growth. Weight measurements were taken every three days as the apical growth endpoint. Gene expression was examined by qPCR for genes in the GH (growth hormone)-IGF1 (insulin-like growth factor 1) pathway, including gh, igf1, and their receptors (ghra, ghrb, igf1ra, igf1rb). In Experiment 1, juvenile mummichog were exposed to excess or limited feed for 21 days. The limited-fed mummichog weighed less, were …

Examining Seasonality Of Zooplankton Communities And Water Quality In Yellowknife Area Lakes, Northwest Territories, Nicole Andreola

Theses and Dissertations (Comprehensive)

Frame Lake, located in Yellowknife, Northwest Territories, is one of the city's main attractions. Unfortunately, urbanization and eutrophication have led to a decline in water quality in the lake. Eutrophication has caused a buildup of organic matter in sediments on the bottom of the lake, which can cause a high oxygen demand when processed by aerobic bacteria. Dissolved oxygen levels are high during the summer, but ice shields the lake from gas exchange with the atmosphere, leading to winter anoxia. This oxygen depletion makes it impossible for sensitive aquatic life, such as fish, to survive in the lake over the …

Assessing Stormwater Management Pond Water Quality, Function, And The Potential Biotic Effects To Receiving Waters, Mitchell Elstone

Theses and Dissertations (Comprehensive)

The use of stormwater management ponds (SWMPs) has been increasing over the past five decades. However, an in-depth understanding of the daily performance of SWMPs and functionality during cold periods is limited. This is in part because mandated monitoring is relatively infrequent, and the assumption that SWMPs are inactive between storm events and during the winter. The goals of this research were to better understand daily stormwater (SW) characteristics, the performance of SWMPs based on current forms of evaluation and assess the potential for SWMP effluent to impact downstream biota. Influent and effluent samples from two SWMPs were collected daily …

Mapping With The Land: Co-Developing A Cumulative Impact Monitoring And Land Stewardship Framework With Sambaa K’E First Nation, Northwest Territories, Canada, Michael S. Mcphee

Theses and Dissertations (Comprehensive)

Across the Northwest Territories (NWT), Canada, Indigenous populations are striving to achieve effective environmental protection, whilst navigating complex methods, policies, and research relationships within co-management contexts. This thesis seeks to identify how differing cultural systems, environmental change, and fractured partnerships may be unified to align with the needs of the Sambaa K’e First Nation (SKFN), a remote Dehcho Dene community. Indigenous methodologies guided co-development of research questions with SKFN leadership which yielded objectives a) develop a GIS-based method to manage, organize and mobilize cultural and environmental data; b) develop a new stewardship monitoring procedure so that users can apply the …

Understanding The Significance Of Object Recognition In Cowbirds: Exploring The Interplay Of Cognition, Social Behaviour And Reproductive Success, Eric Rushton

Theses and Dissertations (Comprehensive)

Every day, animals use cognitive processes to make decisions in their environment such as those regarding food sources, threats and mates. One such important process provides the ability to recognize objects and individuals in order to guide future actions. Since object recognition and individual recognition are related processes, they may be linked to social cognition and to fitness; links not commonly explored in the literature. In this thesis I seek to examine (1) how brown-headed cowbirds (Molothrus ater) attend to and react to novel objects in their environment and (2) how this ability to recognize objects is related …

Fishes In Murky Waters: Effects Of Total Suspended Solids On Fish Gills And Performance, Xena Montoya

Theses and Dissertations (Comprehensive)

Total suspended solids (TSS) naturally occur in aquatic habitats, but climate change and other anthropogenic disturbances can lead to increased levels. Exposure to high levels of TSS has the potential to damage fish gills through abrasion, leading to impairment of gill function and fish physiology. However, little work has been done exploring the linkages between TSS-induced gill damage and animal performance. Therefore, we tested the hypothesis that TSS damages gill structure, causing gill dysfunction and reducing swimming performance. We exposed salmonids (rainbow trout, brook trout and cutthroat trout) and non-salmonids (fathead minnow and longnose dace) to different TSS concentrations (0-1000 …

Understanding Health And Well-Being Outcomes Associated With Protected Coastal Ecosystems: A Fundy National Park Case Study., Mhairi K. Chandler

Theses and Dissertations (Comprehensive)

The COVID-19 pandemic has significantly impacted the mental health and well-being of Canadians, prompting many to turn to nature for consolation and social interaction. However, there is a lack of evidence linking these outcomes specifically to coastal areas. To address this gap, we conducted a self-reported survey at Fundy National Park, New Brunswick, Canada, in summer 2022. Over 400 visitors participated, revealing nature enjoyment, physical health, and mental well-being as primary motivators for park visitation. Notably, mental well-being showed significant differences across gender, sexual identity, and ethnicity, with males, straight individuals, and others exhibiting distinct preferences compared to females, 2SLGBTQIA+ …

Characterizing The Targeting Pathway Of Chloroplast Outer Membrane Protein Oep18 In Arabidopsis Thaliana And Other Targeting Signals Utilized By Outer Envelope Membrane Proteins, Ceaira Hiemstra

Theses and Dissertations (Comprehensive)

Approximately 95% of chloroplast proteins are encoded by nuclear DNA and are post-translationally targeted to the chloroplast. Over half of the 138 known or predicted chloroplast outer membrane (OM) proteins are predicted to utilize four non-canonical targeting pathways. The first two pathways are characterized by containing a single α-helical transmembrane domain (TMD) within the first or last 50 amino acids (AAs), the third pathway is utilized by β-barrels, and the last requires an N-terminal cleavable transit peptide (TP). Recently, a fifth novel pathway called Toc159-like (TOC159L) has been characterized by the presence of a C-terminal reverse TP in Toc159. Subsequent …

Integrating Biodiversity Protection And Climate Mitigation In Nature-Based Climate Solutions: An Indicator Analysis, Tatyana Feiner

Theses and Dissertations (Comprehensive)

Climate change and biodiversity loss have been recognized as complex, interconnected issues that require synergistic and mutually reinforcing policy solutions. Given the ambitious commitments by the Canadian government to abate the two “wicked problems”, this study investigates whether the government has constructed a policy framework that synthesizes climate and biodiversity concerns through policy integration and mainstreaming processes. Through a semi-systematic and comprehensive content analysis approach, this study assesses the degree to which biodiversity protection and climate mitigation have been effectively mainstreamed into federal policies, programs, and instruments. Specifically, the study constructs an evaluative framework based on established “best practices” of …

Language Acquisition, Mental Health, And Acculturation Among Migrants In Canada, Ali Jasemi

Theses and Dissertations (Comprehensive)

This dissertation examines the integration of first-generation migrants in Canada, focusing on the constructs of acculturation, language proficiency, and mental health. With nearly a quarter of Canada's population comprising migrants (Statistics Canada, 2022), understanding their adjustment is critical. Acculturation, language proficiency, and mental health can all have an impact on the success of migrants in their new country (Balidemaj et al. 2019; Brance et al. 2023; Iversen et al. 2014; Rousseau et al. 2019; Rashtchi et al. 2012; Salami et al. 2019). There are a limited number of studies examining these variables in relation to certain migrant groups, such as …

From The Invisible Man To Cozy Closets: Gender Diverse Student Narratives In Ontario Catholic Schools, Yvonne Runstedler

Theses and Dissertations (Comprehensive)

In the province of Ontario, Catholic schools have public funding from the Ministry of Education and ecclesial oversight from the local Catholic diocese. Transgender students who attend these schools experience both governmental spaces and religious ones. The inherent secular and theological tensions responsive to Two-Spirit, Lesbian, Gay, Bisexual Transgender, intersex, Asexual, and other queer-identities [2SLGBTQIA+] students are the overarching contexts of this study. While many Catholic school boards have completed publicly-facing acts of inclusion for 2SLGBTQIA+ students, such as raising the Pride Flag in June in recent years, there is a scarcity of literature responsive to how transgender students make …

Assessing Road Dust Impacts On Macroinvertebrates Community Structure In Canadian Arctic Lakes, Hong Yi Gao

Theses and Dissertations (Comprehensive)

In the Canadian Arctic, unpaved gravel roads are essential for regional accessibility but are also potential sources of road dust runoff. My study investigated the impacts of road dust from the Dempster and Inuvik-Tuktoyaktuk Highways on adjacent freshwater ecosystems, focusing on water quality parameters and macroinvertebrate communities. Using a stratified random sampling design, 18 lakes were studied across two regions (boreal forest and tundra) and three distance categories from the road (0-300 m, 300-600 m, and > 600 m). Contrary to my initial hypotheses, findings revealed no significant differences in water quality or invertebrate communities relative to distance from the road. …

Association Between Papillary Thyroid Cancer And Xrcc6 Gene Polymorphisms In The Turkish Population, Egemen Akgün, Fadi̇me Mutlu İçduygu, Demet Şengül, Ebru Alp, Mehmet Alkanat, Aysegül Cebi̇, Tuncer Ozturk

Turkish Journal of Medical Sciences

Background/aim: This study aims to investigate the association between rs2267437, rs5751129 and rs132770 polymorphisms of the XRCC6 gene, which plays a role in repairing DNA double strand breaks, and the risk of Papillary Thyroid Cancer (PTC).Methods: The study included 150 patients who had been diagnosed with PTC and 204 healthy control subjects. Genotyping of SNPs was performed by Polymerase Chain Reaction - Restriction Fragment Length Polymorphism method (PCR - RFLP).Results: In rs2267437 polymorphism, individuals with GG genotype had lower risk of PTC than wild-type CC genotype (p=0.037, 95% CI=0.19-0.96, OR=0.67). The combined genotypes CG+GG were found to be related to …

Evaluation Of The Association Of Mucosa-Associated Invariant T (Mait) Cells With Childhood Asthma, Meral Ekşi̇, Huri̇ Bulut, Erdem Akalin, Feyza Ustabaş Kahraman, Hakan Yazan, Mebrure Yazici, Mustafa Nursoy, Emi̇n Özkaya, Abdürrahi̇m Koçyi̇ği̇t, Erkan Çakir

Turkish Journal of Medical Sciences

Background/aim: Innate-like T lymphocytes are a recently defined group of T cells comprising mainly mucosa-associated invariant T (MAIT) cells. The relationship between MAIT cells and childhood asthma is controversial. In this study, we aimed to determine the role of MAIT cells in patients with allergic asthma (AA) and nonallergic asthma (NAA). This is the first study to compare the ratios of these cells in patients with AA and NAA.Materials and methods: The study included children aged 6–18 years with AA (n = 41) or NAA (n = 30) and healthy control subjects (n = 36). The control group consisted of …

Adverse Childhood Experiences Of Professional School Counselors As Predictors Of Compassion Satisfaction, Burnout, And Secondary Traumatic Stress, Eric M. Brown, Melanie Burgess, Kristy L. Carlisle, Desmond Franklin Davenport, Michelle W. Brasfield

Counseling & Human Services Faculty Publications

School counselors work closely with students and are often the first point of contact regarding traumatic experiences. It is generally understood that exposure to other individuals’ trauma may lead to a reduction in compassion satisfaction and an increase in secondary traumatic stress, while long-term exposure may result in professional burnout. This study examined the role of school counselors’ (N = 240) own adverse childhood experiences (ACEs) as related to compassion satisfaction, secondary traumatic stress, and burnout. Results indicated that 50% of the professional school counselors in this convenience sample had personal histories of four or more ACEs, which is significantly …

Tract-Based Analyses Of White Matter In Schizophrenia, Bipolar Disorder, Aging, And Dementia Using High Spatial And Directional Resolution Diffusion Imaging: A Pilot Study, Daniel Mamah, Shingshiun Chen, Joshua S Shimony, Michael P Harms

2020-Current year OA Pubs

INTRODUCTION: Structural brain connectivity abnormalities have been associated with several psychiatric disorders. Schizophrenia (SCZ) is a chronic disabling disorder associated with accelerated aging and increased risk of dementia, though brain findings in the disorder have rarely been directly compared to those that occur with aging.

METHODS: We used an automated approach to reconstruct key white matter tracts and assessed tract integrity in five participant groups. We acquired one-hour-long high-directional diffusion MRI data from young control (CON, n =28), bipolar disorder (BPD, n =21), and SCZ (n =22) participants aged 18-30, and healthy elderly (ELD, n =15) and dementia (DEM, n …

Traffic Prediction-Based Vnf Auto-Scaling And Deployment Mechanism For Flexible And Elastic Service Provision, Bo Yi, Jiacheng Wang, Qiang He, Xingwei Wang, Min Huang, Sajal K. Das, Keqin Li

Computer Science Faculty Research & Creative Works

Network Function Virtualization (NFV) provides a flexible way to provision new services by decoupling network functions from hardware and implementing them as Virtual Network Functions (VNFs). However, the rapid development of technologies greatly promotes the explosion of diverse services, which directly results in the exponential increase of heterogeneous traffic. In addition, such a tremendous amount of heterogeneous traffic will generate bursts in a more dynamic and unexpected manner, so it becomes extremely hard to satisfy the customer demands. Aiming at addressing these challenges, this work proposes a positive and elastic VNF deployment mechanism for service provisioning, which introduces three novelties: …

Elevating Voices, Addressing Depression, Toxic Stress, And Equity Through Group Prenatal Care: A Pilot Study, Shannon N Lenze, Kelly Mckay-Gist, Rachel Paul, Melissa Tepe, Katherine Mathews, Sara Kornfield, Cheron Phillips, Richelle Smith, Amanda Stoermer, Ebony B Carter

2020-Current year OA Pubs

INTRODUCTION: Elevating Voices, Addressing Depression, Toxic Stress and Equity (EleVATE) is a group prenatal care (GC) model designed to improve pregnancy outcomes and promote health equity for Black birthing people. This article outlines the foundational community-engaged process to develop EleVATE GC and pilot study results.

METHODS: We used community-based participatory research principles and the Ferguson Commission Report to guide creation of EleVATE GC. The intervention, designed by and for Black birthing people, centers trauma-informed care, antiracism, and integrates behavioral health strategies into group prenatal care to address unmet mental health needs. Using a convenience sample of patients seeking care at …

The Response Of Dual-Leucine Zipper Kinase (Dlk) To Nocodazole: Evidence For A Homeostatic Cytoskeletal Repair Mechanism, Laura Devault, Chase Mateusiak, John Palucki, Michael Brent, Jeffrey Milbrandt, Aaron Diantonio

2020-Current year OA Pubs

Genetic and pharmacological perturbation of the cytoskeleton enhances the regenerative potential of neurons. This response requires Dual-leucine Zipper Kinase (DLK), a neuronal stress sensor that is a central regulator of axon regeneration and degeneration. The damage and repair aspects of this response are reminiscent of other cellular homeostatic systems, suggesting that a cytoskeletal homeostatic response exists. In this study, we propose a framework for understanding DLK mediated neuronal cytoskeletal homeostasis. We demonstrate that low dose nocodazole treatment activates DLK signaling. Activation of DLK signaling results in a DLK-dependent transcriptional signature, which we identify through RNA-seq. This signature includes genes likely …

Leveraging Murine Models Of The Neurofibromatosis Type 1 Cancer Predisposition Syndrome To Elucidate The Cellular Circuits That Drive Pediatric Low-Grade Glioma Formation And Progression, David H Gutmann

2020-Current year OA Pubs

Brain tumors are the leading cause of cancer-related death in children, where low-grade gliomas (LGGs) predominate. One common hereditary cause for LGGs involves neurofibromatosis-1 (NF1) gene mutation, as seen in individuals with the NF1 cancer predisposition syndrome. As such, children with NF1 are at increased risk of developing LGGs of the optic pathway, brainstem, cerebellum, and midline brain structures. Using genetically engineered mouse models, studies have revealed both cell-intrinsic (MEK signaling) and stromal dependencies that underlie their formation and growth. Importantly, these dependencies represent vulnerabilities against which targeted agents can be used for preclinical investigation prior to clinical translation.

Intermuscular Coherence As An Early Biomarker For Amyotrophic Lateral Sclerosis: The Protocol For A Prospective, Multicenter Study, Naoum P Issa, Serdar Aydin, Eric Polley, Nathan Carberry, Mark A. Garret, Sean Smith, Ali A. Habib, Nicholas W. Baumgartner, Betty Soliven, Kourosh Rezania

2020-Current year OA Pubs

OBJECTIVE: To describe the protocol of a prospective study to test the validity of intermuscular coherence (IMC) as a diagnostic tool and biomarker of upper motor neuron degeneration in amyotrophic lateral sclerosis (ALS).

METHODS: This is a multicenter, prospective study. IMC of muscle pairs in the upper and lower limbs is gathered in ∼650 subjects across three groups using surface electrodes and conventional electromyography (EMG) machines. The following subjects will be tested: 1) neurotypical controls; 2) patients with symptomatology suggestive for early ALS but not meeting probable or definite ALS by Awaji Criteria; 3) patients with a known ALS mimic. …

Advancements And Challenges In Additively Manufactured Functionally Graded Materials: A Comprehensive Review, Suhas Alkunte, Ismail Fidan, Vivekanand Naikwadi, Shamil Gudavasov, Mohammad Alshaikh Ali, Mushfig Mahmudov, Seymur Hasanov, Muralimohan Cheepu

Engineering Technology Faculty Publications

This paper thoroughly examines the advancements and challenges in the field of additively manufactured Functionally Graded Materials (FGMs). It delves into conceptual approaches for FGM design, various manufacturing techniques, and the materials employed in their fabrication using additive manufacturing (AM) technologies. This paper explores the applications of FGMs in diverse fields, including structural engineering, automotive, biomedical engineering, soft robotics, electronics, 4D printing, and metamaterials. Critical issues and challenges associated with FGMs are meticulously analyzed, addressing concerns related to production and performance. Moreover, this paper forecasts future trends in FGM development, highlighting potential impacts on diverse industries. The concluding section summarizes …

Energy Efficiency In Additive Manufacturing: Condensed Review, Ismail Fidan, Vivekanand Naikwadi, Suhas Alkunte, Roshan Mishra, Khalid Tantawi

Engineering Technology Faculty Publications

Today, it is significant that the use of additive manufacturing (AM) has growing in almost every aspect of the daily life. A high number of sectors are adapting and implementing this revolutionary production technology in their domain to increase production volumes, reduce the cost of production, fabricate light weight and complex parts in a short period of time, and respond to the manufacturing needs of customers. It is clear that the AM technologies consume energy to complete the production tasks of each part. Therefore, it is imperative to know the impact of energy efficiency in order to economically and properly …

Cep120 Is Essential For Kidney Stromal Progenitor Cell Growth And Differentiation, Ewa Langner, Tao Cheng, Eirini Kefaloyianni, Charles Gluck, Baolin Wang, Moe R Mahjoub

2020-Current year OA Pubs

Mutations in genes that disrupt centrosome structure or function can cause congenital kidney developmental defects and lead to fibrocystic pathologies. Yet, it is unclear how defective centrosome biogenesis impacts renal progenitor cell physiology. Here, we examined the consequences of impaired centrosome duplication on kidney stromal progenitor cell growth, differentiation, and fate. Conditional deletion of the ciliopathy gene Cep120, which is essential for centrosome duplication, in the stromal mesenchyme resulted in reduced abundance of interstitial lineages including pericytes, fibroblasts and mesangial cells. These phenotypes were caused by a combination of delayed mitosis, activation of the mitotic surveillance pathway leading to apoptosis, …

Non-Invasive Auricular Vagus Nerve Stimulation For Subarachnoid Hemorrhage (Navsah): Protocol For A Prospective, Triple-Blinded, Randomized Controlled Trial, Anna Huguenard, Gansheng Tan, Gabrielle Johnson, Markus Adamek, Andrew Coxon, Terrance Kummer, Joshua Osbun, Ananth Vellimana, David Limbrick, Gregory Zipfel, Peter Brunner, Eric Leuthardt

2020-Current year OA Pubs

BACKGROUND: Inflammation has been implicated in driving the morbidity associated with subarachnoid hemorrhage (SAH). Despite understanding the important role of inflammation in morbidity following SAH, there is no current effective way to modulate this deleterious response. There is a critical need for a novel approach to immunomodulation that can be safely, rapidly, and effectively deployed in SAH patients. Vagus nerve stimulation (VNS) provides a non-pharmacologic approach to immunomodulation, with prior studies demonstrating VNS can reduce systemic inflammatory markers, and VNS has had early success treating inflammatory conditions such as arthritis, sepsis, and inflammatory bowel diseases. The aim of the Non-invasive …