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A Comprehensive Catalog Of Post-Translational Modifications Of Drosophila Melanogaster Hox Protein, Sex Combs Reduced, Anirban Banerjee

Electronic Thesis and Dissertation Repository

During formation of the anterior-posterior axis, Homeotic selector (HOX) proteins determine the identity of Drosophila body segments. HOX proteins are transcription factors that regulate gene expression during development. Besides a highly conserved DNA-binding homeodomain (HD), HOX proteins also contain functionally important, evolutionarily conserved small motifs. These short motifs found in HOX proteins may be Short Linear Motifs (SLiMs). SLiMs are proposed to be sites of phosphorylation and this may regulate the activity of HOX proteins. The primary aim of this work was to develop a comprehensive catalogue of the sites of phosphorylation and other post-translational modifications (PTMs) for Fushi tarazu …

Bicuspid Aortic Valve Formation: Nos3 Mutation Leads To Abnormal Lineage Patterning Of Neural Crest Cells And The Second Heart Field, Joshua C. Peterson, Mary Chughtai, Lambertus J. Wisse, Adriana C. Gittenberger-De Groot, Qingping Feng, Marie J.T.H. Goumans, J. Conny Vanmunsteren, Monique R.M. Jongbloed, Marco C. Deruiter

Paediatrics Publications

The bicuspid aortic valve (BAV), a valve with two instead of three aortic leaflets, belongs to the most prevalent congenital heart diseases in the world, occurring in 0.5-2% of the general population. We aimed to understand how changes in early cellular contributions result in BAV formation and impact cardiovascular outflow tract development. Detailed 3D reconstructions, immunohistochemistry and morphometrics determined that, during valvulogenesis, the non-coronary leaflet separates from the parietal outflow tract cushion instead of originating from an intercalated cushion. Nos3−/− mice develop a BAV without a raphe as a result of incomplete separation of the parietal outflow tract cushion into …

Latest Advances In Intervertebral Disc Development And Progenitor Cells, Cheryle A. Séguin, Danny Chan, Chitra L. Dahia, Zulma Gazit

Paediatrics Publications

This paper is a concise review aiming to assemble the most relevant topics presented by the authors at ORS-Philadelphia Spine Research Society Fourth International Spine Research Symposium. It centers on the latest advances in disc development, its main structural entities, and the populating cells, with emphasis on the advances in pivotal molecular pathways responsible for forming the intervertebral discs (IVD). The objective of finding and emphasizing pathways and mechanisms that function to control tissue formation is to identify and to explore modifications occurring during normal aging, disease, and tissue repair. Thus, to comprehend that the cellular and molecular basis of …

The Effects Of Early Adolescent Lipopolysaccharide Or Cat Odour Exposure Followed By Propionic Acid Administration On Anxiety, Startle Response, And Sensorimotor Gating In Adolescence And Adulthood, Deanne Tak On Wah

Electronic Thesis and Dissertation Repository

Autism spectrum disorders (ASD) are caused by genetic factors and a complex set of risk factors including early stressors and alterations in the gut microbiome. The present thesis investigated whether environmental stressors during early adolescence predisposes rats administered another stressor in later adolescence and adulthood to produce altered anxiety-like behaviours, startle response, and percent prepulse inhibition. The early adolescent stressors used in this study included repeated administration of a bacterial endotoxin, lipopolysaccharide (LPS), or a stressful predator cat odour exposure. In later adolescence and adulthood, rats were administered with a gut microbial by-product, propionic acid (PPA), and subsequently tested on …

Factors Contributing To Preschoolers' Communicative Participation Outcomes: Findings From A Population-Based Longitudinal Cohort Study In Ontario, Canada, Barbara Jane Cunningham, Steven E. Hanna, Peter Rosenbaum, Nancy Thomas-Stonell, Bruce Oddson

PRECISe Preschool Speech and Language Publications

Purpose. To identify predictors of communicative participation outcomes for a large cohort of preschoolers with communication disorders.

Method. A secondary analysis of longitudinal program evaluation data from Ontario Canada’s Preschool Speech and Language Program (PSLP). Data available for 46,872 children 18-67 months of age (M = 41.76 mo, SD = 11.92, 68% male) were previously used to predict children’s communicative participation skill development in five levels of function. Demographic and intervention-based variables were added to the models to identify new predictors of growth.

Results. Three demographic and three intervention-based variables were statistically significant predictors of children’s communicative participation …

Settlement Experiences Of Syrian Refugees, Jennifer Perkins

Electronic Thesis and Dissertation Repository

Statistics Canada (2017) reports that over 40,000 Syrian refugees have arrived in Canada since November of 2015. This large influx of refugees, some with psychological trauma, poses a great responsibility to service providers to ensure services meet the needs of their new clientele. One service provider in Midsized City, Ontario, which will be referred to as The Resource Center, has taken a new and culturally informed approach to providing service. This center has held multiple “Welcome Neighbour” events across the city to invite newcomers to form a closer community and give them the platform to express their needs as refugees. …

Symbolic And Material Justice: The Case Of Displaced Persons In Chocó, Colombia, Allison Cordoba

Electronic Thesis and Dissertation Repository

This research examines the causes and impacts of victimization as experienced by rural populations displaced by conflict living in Quibdó, Colombia. It draws upon Bourdieu’s social theory to understand how the distribution of various forms of capital structure the lives of the displaced. A brief history of the conflict in Colombia is presented, which is broken into five periods, from 1946 to 2014 when the fieldwork was conducted. A description of the context of Quibdó and the department it is in, Chocó, is also provided. Particular attention is paid to the role of symbolic, economic, and cultural capital in the …

Mind The Gap: Mapping Skills In Higher Education Project Summary, Melody Viczko Dr, Shannon Mckechnie, Natasja Van Buggenhout, J. Eduardo Álvarez Barrios

Education Publications

The call for reform in higher education has been a focus of the Organization for Economic Co-operation and Development (OECD) for over a decade. This call for reform is driven by a stated “skills gap” between the skills of graduates and the needs of the labour market. Student groups have also voiced their concern about the skills gap and its impact on future employment.

Candid: A Framework For Linking Executive Function And Education, Niki H. Kamkar, J. B. Morton

Brain and Mind Institute Researchers' Publications

The close association between executive functions (EFs) and educational achievement has led to the idea that targeted EF training might facilitate learning and goal-directed behavior in the classroom. The evidence that training interventions have long-lasting and transferable effects is however decidedly mixed (Melby-Lervåg and Hulme, 2013; Simons et al., 2016). The goal of the current paper is to propose a new CanDiD framework for re-thinking EF and its links to education. Based on findings from basic EF research, the proposed CanDiD framework highlights dynamic and contextual influences on EF and emphasizes the importance of development and individual differences for understanding …

Predictors Of Language Outcome For Children In The Ontario Infant Hearing Program, Olivia M. Daub

Electronic Thesis and Dissertation Repository

The Ontario Infant Hearing Program (OIHP) provides early interventions (i.e., hearing aids) to children who are hard of hearing (CHH) because research consistently demonstrates their benefit to language outcomes. The impact of pre-fitting language abilities on these outcomes are not well understood.

This retrospective cohort analysis examined the performance of OIHP children on the Preschool Language Scale-4 at the time of (n=47), and after (n=19), initial hearing aid intervention. Regression analyses revealed that, before amplification, hearing loss severity predicted language abilities. However, after amplification, severity of hearing loss did not uniquely predict language achievement, but rather …

Cross-Modal Plasticity In Higher-Order Auditory Cortex Of Congenitally Deaf Cats Does Not Limit Auditory Responsiveness To Cochlear Implants, Rüdiger Land, Peter Baumhoff, Jochen Tillein, Stephen G. Lomber, Peter Hubka, Andrej Kral

Brain and Mind Institute Researchers' Publications

Congenital sensory deprivation can lead to reorganization of the deprived cortical regions by another sensory system. Such cross-modal reorganization may either compete with or complement the “original” inputs to the deprived area after sensory restoration and can thus be either adverse or beneficial for sensory restoration. In congenital deafness, a previous inactivation study documented that supranormal visual behavior was mediated by higher-order auditory fields in congenitally deaf cats (CDCs). However, both the auditory responsiveness of “deaf” higherorder fields and interactions between the reorganized and the original sensory input remain unknown. Here, we studied a higher-order auditory field responsible for the …

Further Support For Thermal Ecosystem Engineering By Wandering Albatross On Marion Island, Steven L Chown, Justine D. Shaw, Tanya M Haupt, Brent J Sinclair

Biology Publications

On sub-Antarctic Marion Island, wandering albatross (Diomedea exulans) nests support high abundances of tineid moth, Pringleophaga marioni, caterpillars. Previous work proposed that the birds serve as thermal ecosystem engineers by elevating nest temperatures relative to ambient, thereby promoting growth and survival of the caterpillars. However, only 17 days of temperature data were presented previously, despite year-long nest occupation by birds. Previous sampling was also restricted to old and recently failed nests, though nests from which chicks have recently fledged are key to understanding how the engineering effect is realized. Here we build on previous work by providing nest temperature data …

Ethanol Exposure During Synaptogenesis In A Mouse Model Of Fetal Alcohol Spectrum Disorders: Acute And Long-Term Effects On Gene Expression And Behaviour, Morgan L. Kleiber

Electronic Thesis and Dissertation Repository

Alcohol is a neuroactive molecule that is able to exert variable and often detrimental effects on the developing brain, resulting in a broad range of physiological, behavioural, and cognitive phenotypes that characterize ‘fetal alcohol spectrum disorders’ (FASD). Factors affecting the manifestation of these phenotypes include alcohol dosage, timing of exposure, and pattern of maternal alcohol consumption; however, the biological processes that are vulnerable to ethanol at any given neurodevelopmental stage are unclear, as is how their disruption results in the emergence of specific pathological phenotypes later in life.

The research included in this thesis utilizes a C57BL/6J (B6) mouse model …

Transient And Permanent Effects Of Suboptimal Incubation Temperatures On Growth, Metabolic Rate, Immune Function And Adrenocortical Responses In Zebra Finches, Haruka Wada, Buddhamas Kriengwatana, Natalie Allen, Kimberly L. Schmidt, Kiran K. Soma, Scott A. Macdougall-Shackleton

Brain and Mind Institute Researchers' Publications

In birds, incubation temperature can vary by several degrees Celsius among nests of a given species. Parents may alter incubation temperature to cope with environmental conditions and/or to manipulate embryonic development, and such changes in incubation behavior could have long-lasting effects on offspring phenotype. To investigate short- and long-term effects of suboptimal incubation temperatures on survival and physiological functions in zebra finches, eggs were incubated at 36.2, 37.4 or 38.4°C for the entire incubation period. The post-hatch environment was identical among the treatment groups. We found that hatching success was lowest in the 38.4°C group, while post-hatch survival was lowest …

The Role Of Connexins And Pannexins In Mammary Gland Development And Tumorigenesis, Michael K. G. Stewart

Electronic Thesis and Dissertation Repository

The identification of key regulators of breast cancer onset and progression is critical for the development of targeted therapies. Connexins and pannexins are characterized by their ability to form large-pore channels and are frequently dysregulated in cancer. However, their role in breast cancer progression remains poorly understood due to a lack of in vivo models capable of assessing the proposed and opposing roles of connexins and pannexins as both tumor suppressors and/or facilitators in multiple stages of the disease. Using 2 previously uncharacterized genetically-modified mice, connexin43 (Cx43) and connexin26 (Cx26) were evaluated for their role in normal mammary gland development …

Eyetracking Of Coarticulatory Cue Responses In Children And Adults, Alexandra M. Cross

Electronic Thesis and Dissertation Repository

Studies examining sensitivity to coarticulatory cues during spoken word recognition have typically examined children and adults separately. The present thesis compared sensitivity to coarticulatory cues in school-aged children and adults using eyetracking. Children and adults listened to words containing congruent and incongruent coarticulatory cues while looking at a two-picture display. Contrary to theories positing weakened attention to phonetic detail in children, we observed equal or greater sensitivity to coarticulatory cues in children compared to adults. This effect was related to predictors of reading and language proficiency, and was also modulated by phoneme contrasts such that children were overly sensitive to …

Retinoic Acid And The Development Of The Endoderm, Gregory M. Kelly, Thomas A. Drysdale

Paediatrics Publications

Retinoic acid (RA) is an important signaling molecule in the development of the endoderm and an important molecule in protocols used to generate endodermal cell types from stem cells. In this review, we describe the RA signaling pathway and its role in the patterning and specification of the extra embryonic endoderm and different endodermal organs. The formation of endoderm is an ancient evolutionary feature and RA signaling appears to have coevolved with the vertebrate lineage. Towards that end, we describe how RA participates in many regulatory networks required for the formation of extraembryonic structures as well as the organs of …

Multi-Method Exploration Of The Economic Sustainability Of Probiotic Yoghurt Kitchens In Mwanza, Tanzania, Emily Eyles

Electronic Thesis and Dissertation Repository

This research aimed to examine the economic and locational aspects of a probiotic yoghurt kitchen development project facilitated by Western Heads East in Mwanza, Tanzania. This study is based upon 41 semi-structured interviews with 57 participants in three groups: kitchen group members, customers, and staff of the African Probiotic Yoghurt Network. This research contributes to the literature on development geography, specifically on the ins and outs of the everyday of the kitchens, as well as proposing a new approach to multicriteria evaluation using qualitative data, and the ‘researcher as instrument’ approach. The results demonstrate that while there are problems in …

Introduction: Working With, Against And Despite Global 'Best Practices': Educational Conversations Around The Globe, Sarfaroz Nivozov, Paul Tarc

Education Publications

No abstract provided.

Pancreatic Beta Cell Plasticity And Involvement Of Insulin-Expressing Progenitor Cells, Christine A. Beamish

Electronic Thesis and Dissertation Repository

Islet transplants have been successfully used as treatment for diabetes, but are limited by shortages of cadaveric insulin-producing β-cells. An alternate source may be the dedifferentiation, expansion, and subsequent redifferentiation of pancreatic islets or β-cells using in vitro techniques prior to transplant. Based on protocols which described the dedifferentiation of human islets to ductal-like cells, we hypothesized that neonatal mouse islets could be similarly dedifferentiated in vitro. Dedifferentiation techniques produced significant duct-like cells, but redifferentiation to insulin-expressing cells was limited. RIPCre;Z/AP+/+ mice were consequently utilized to lineage trace β-cell fate during culture by a human placental alkaline phosphatase (HPAP) reporter. …

A Method For Investigating Age-Related Differences In The Functional Connectivity Of Cognitive Control Networks Associated With Dimensional Change Card Sort Performance, Bianca Debenedictis, J. Bruce Morton

Paediatrics Publications

The ability to adjust behavior to sudden changes in the environment develops gradually in childhood and adolescence. For example, in the Dimensional Change Card Sort task, participants switch from sorting cards one way, such as shape, to sorting them a different way, such as color. Adjusting behavior in this way exacts a small performance cost, or switch cost, such that responses are typically slower and more error-prone on switch trials in which the sorting rule changes as compared to repeat trials in which the sorting rule remains the same. The ability to flexibly adjust behavior is often said to develop …

Taking Tone Into Account: Cognitive Neuroscientific Investigations Of Mandarin Chinese Spoken Word Processing, Jeffrey G. Malins

Electronic Thesis and Dissertation Repository

To date, theories of how humans recognize spoken words have yet to account for tonal languages such as Mandarin Chinese. One reason for this is that we know relatively little about how native speakers of tonal languages process spoken words in the brain. This dissertation addresses this problem by examining Mandarin spoken word processing in both adult native speakers and typically developing children. In adults, functional magnetic resonance imaging (fMRI) was used to assess the extent to which the brain regions involved in processing tonal information are distinct from those involved in vowel processing (Chapter 2), while event related potentials …

Developmental Characterization Of Tissue Inhibitor Of Metalloproteinase Domain Functions In Xenopus Laevis, Michelle A. Nieuwesteeg

Electronic Thesis and Dissertation Repository

During development the extracellular matrix is cleaved and remodeled to facilitate the large-scale cell rearrangements that are necessary for processes like gastrulation, neurulation, angiogenesis and organogenesis. ECM remodeling occurs primarily through secreted enzymes called matrix metalloproteinases (MMPs). Regulation of MMP activity is achieved through the tissue inhibitor of metalloproteinases (TIMPs), a small family of secreted proteins that bind MMPs in a 1:1 manner to inhibit their activity. Although TIMPs were originally characterized based on their MMP-inhibitory activities, in vitro studies have revealed that TIMPs are multifunctional proteins, with structurally and functionally distinct N- and C-terminal domains. TIMP N-terminal domains bind …

Voices Of Youth In An Ethiopian Ngo's Educational Program: A Holistic View At Enabling Factors, Nathalie Piquemal

Comparative and International Education / Éducation Comparée et Internationale

This paper explores the impact that a Canadian NGO’s supported educational programs in Ethiopia have had on orphaned and vulnerable young people, socially, emotionally, and academically, as experienced, storied and understood by the children and adolescents themselves. Using Bronfenbrenner’s (2005) bio-ecological theory of human development as a theoretical framework and qualitative inquiry, specifically semi-structured interviews with 37 children and youths between 9 and 17 years old, as a methodological framework, this study explores factors that promote empowerment, resilience, and hope though students’ experiences and perceptions in these NGO’s educational programs. Discussion includes reflection gender, social justice, and implications for practice …

Dimensional Change Card Sort Performance Associated With Age-Related Differences In Functional Connectivity Of Lateral Prefrontal Cortex, Fredrick Ezekiel, Rachael Bosma, J. Bruce Morton

Paediatrics Publications

The Dimensional Change Card Sort (DCCS) is a standard procedure for assessing executive functioning early in development. In the task, participants switch from sorting cards one way (e.g., by color) to sorting them a different way (e.g., by shape). Traditional accounts associate age-related changes in DCCS performance with circumscribed changes in lateral prefrontal cortex (lPFC) functioning, but evidence of age-related differences in the modulation of lPFC activity by switching is mixed. The current study therefore tested for possible age-related differences in functional connectivity of lPFC with regions that comprise a larger cognitive control network. Functional magnetic resonance imaging (fMRI) data …

Tu Envidia Es Mi Progreso: An Ethnographic Account Of The Development Of Squatter Settlements In San Juan De Miraflores, Lima, Peru., Brandon E. Rouleau

Electronic Thesis and Dissertation Repository

The following dissertation explores the past 60 years of self-help housing in Lima. Specifically, it looks at the uneven development that has occurred in parts of a municipality called San Juan de Miraflores. I argue that self-help housing is part of a larger modernization project that aims to encourage the emergence of a self-regulating individual. Pro-development literature creates a selective history of marginal neighbourhoods, effectively silencing the histories of working class Miraflorinos. The aim of this ethnographic study is to destabilize official histories and representations about development in marginal communities. The bulk of the dissertation looks at the history of …

Cloning And Analysis Of Reck During Early Xenopus Laevis Development, Jessica Willson

Electronic Thesis and Dissertation Repository

Extracellular matrix (ECM) remodeling is crucial for the development and maintenance of multicellular organisms. Degradation of ECM components occurs through the activity of matrix metalloproteinases (MMPs) and their inhibitors. Reversion-inducing cysteine-rich protein with Kazal motifs (RECK) gene encodes a membrane-anchored protein and plays an important role in mediating ECM remodeling by inhibiting MMPs. To date, few in vivo studies exist examining RECK during development. The present study focuses on cloning and examining the expression of RECK during early Xenopus laevis development. A mature cDNA clone of the RECK gene was generated. RT-PCR, in situ hybridization, and immunohistochemistry were used to …

Rule-Based Category Learning In Children: The Role Of Inhibitory Control, Rahel R. Rabi

Electronic Thesis and Dissertation Repository

The present study examined category learning in relation to inhibitory control and working memory in children and adults. Results revealed that categorization performance improved with age. Young children struggled with rule learning, many older children were successful at rule learning, and most adults had no difficulty with the task. Model-based analyses suggested that performance differences were due to young children’s inability to inhibit the salient, but irrelevant rule. Interestingly, when the analyses focused only on older children and adults who used the task appropriate strategy, the age-related rule-based deficit disappeared. Also, results revealed that successful performance on the categorization task …

The Effects Of Neonatal Immune System Activation With Lipopolysaccharide On Adolescent And Adult Anxiety Behaviours In Male And Female Rats, Alina Zaltzman

Electronic Thesis and Dissertation Repository

The present study examined the effects of neonatal (postnatal days 3 and 5) acute immune system activation with lipopolysaccharide (LPS) on adolescent and adult anxiety behaviours. The major findings suggest that neonatal LPS does not have general long-lasting effects on adolescent anxiety and locomotor behaviours. Rather, early endotoxin treatment has highly specific effects on certain anxiety behaviours that vary depending on the development period. Moreover, neonatal LPS does not seem to influence adult voluntary and non-voluntary locomotor activity or anhedonia, independent of, or in response to, an adult immune challenge. Finally, sex differences were observed in various responses in adulthood, …

The Body Plan Concept And Its Centrality In Evo-Devo, Katherine E. Willmore

Paediatrics Publications

A body plan is a suite of characters shared by a group of phylogenetically related animals at some point during their development. The concept of bauplane, or body plans, has played and continues to play a central role in the study of evolutionary developmental biology (evo-devo). Despite the importance of the body plan concept in evo-devo, many researchers may not be familiar with the progression of ideas that have led to our current understanding of body plans, and/or current research on the origin and maintenance of body plans. This lack of familiarity, as well as former ties between the body …