VictorJuiz/thesis huggingface dataset:
Exercise with a Twist: Left Ventricular Torsion and Recoil in Young, Middle-aged, and Endurance-trained Men

The contribution of left ventricular (LV) torsion and recoil in augmenting stroke volume during exercise is poorly understood. This study examined the effects of aging on LV torsion and recoil at rest and during sub-maximal exercise in 11 young (YU) and 9 older, untrained males (OU), and 12 age-matched older, endurance-trained males (OT) in upright and supine body positions. LV torsion increased from rest to exercise in YU in upright and supine body positions (9.9±2.3 to 13.2±5.2 degrees, p=.03, and 8.8±3.8 to 12.8±6.6 degrees, p=.02, respectively), but not in OU. LV torsion increased with exercise in the supine body position only in OT (p=.046). There were no differences in EDV or change in ESV with supine exercise across groups suggesting that once the Frank-Starling mechanism is fully recruited, the young heart, and that of older, endurance-trained subjects may augment SV by increasing LV torsion and contractility rather than contractility alone.

Keywords: left ventricular torsion
aging
exercise
Advisor: Goodman, Jack
Reversal of Morphine-induced Locomotion in M5 Muscarinic Receptor Knockout Mice with Food Deprivation but not Bilateral Infusions of VTA BDNF

Cholinergic inputs from mesopontine tegmentum activate midbrain dopamine (DA) neurons via M5 muscarinic receptors. The M5 receptor is important for mesopontine stimulation-induced accumbal or striatal DA efflux, brain stimulation reward or morphine-induced conditioned place preference (CPP). M5 receptor knockout (KO) mice show 40-50% less morphine-induced locomotion. Pedunculopontine tegmental nucleus (PPT) lesions in rodents block morphine CPP, but are ineffective after 18 hours food deprivation, opiate dependence, or intra-VTA BDNF. Based on these findings, we investigated whether acute food deprivation or intra-VTA BDNF alters morphine-induced locomotion (3 and 10 mg/kg, i.p.) in C57BL/6 M5 KO mice. Non-deprived M5 KOs showed reduced morphine-induced locomotion, suggesting M5 receptors partly mediate morphine-induced locomotion. Morphine-induced locomotion was reversed in food-deprived mice, suggesting the stimulant effects of morphine were altered to bypass the PPT. Unexpectedly, intra-VTA BDNF infusions were ineffective in altering morphine-induced locomotion. Additionally, M5 KOs receiving intra-VTA saline showed no deficits in morphine-induced locomotion.

Keywords: muscarinic
M5
acetylcholine
dopamine
food deprivation
knockout
mice
morphine
locomotion
brain-derived neurotrophic factor
mesolimbic
pedunculopontine tegmental nucleus
open-field
Advisor: Yeomans, John S.
Timing of Peak Mandibular Growth in Different Facial Growth Patterns and Resultant Mandibular Projection

Objective: To determine if significant differences exist in timings and rates of Peak Mandibular Growth (PMG) and mandibular projections of subjects with vertical, average and horizontal facial growth patterns. Methods: Sixty-three Caucasian orthognathic subjects with cephalograms (9 to 18 years) available from the Burlington Growth Centre were categorized into average, vertical and horizontal growth pattern groups based on their change in Y axis from age 10 to 16 years. PMG timing and rates were determined and mandibular projections measured. Comparisons were made by ANOVA. Results: Inter-group differences of PMG timing or rate were not statistically significant. Although not statistically significant, PMG of vertically growing females was 14 month earlier than all other subgroups. Horizontal mandibular projection differences approached significance in older children. Conclusions: No statistically significant differences were found in the timing or rate of PMG in different facial growth patterns. Differences in horizontal mandibular projections approached significance with growth.

Keywords: peak mandibular growth
mandibular projection
vertical dysplasia
treatment timing
facial growth
Advisor: Suri, Sunjay
Brain State Classification in Epilepsy and Anaesthesia

Transitions between normal and pathological brain states are manifested differently in the electroencephalogram (EEG). Traditional discrimination of these states is often subject to bias and strict definitions. A fuzzy logic-based analysis can permit the classification and tracking of brain states in a non-subjective and unsupervised manner. In this thesis, the combination of fuzzy c-means (FCM) clustering, wavelet, and information theory has revealed notable frequency features in epilepsy and anaesthetic-induced unconsciousness. It was shown that entropy changes in membership functions correlate to specific epileptiform activity and changes in anaesthetic dosages. Seizure episodes appeared in the 31-39 Hz band, suggesting changes in cortical functional organization. The induction of anaesthetics appeared in the 64-72 Hz band, while the return to consciousness appeared in the 32-40 Hz band. Changes in FCM activity were associated with the concentration of anaesthetics. These results can help with the treatment of epilepsy and the safe administration of anaesthesia.

Keywords: EEG
signal processing
epilepsy
anaesthesia
anesthesia
neuroscience
fuzzy logic
entropy
fuzzy c-means clustering
wavelet
classification
brain state
seizure
membership function
Advisor: Bardakjian, Berj
Mechanical Evaluation of a Thiol-modified Hyaluronan Elastin-like Polypeptide Nucleus Pulposus Replacement Material in Porcine Intervertebral Discs

Mechanical low back pain is a disabling condition often associated with degenerative disc disease (DDD). Treatment for DDD includes non-operative pain management, total disc arthroplasty and nucleus pulposus (NP) replacement. A thiol-modified hyaluronan elastin-like polypeptide (TMHA/EP) composite has been under consideration as a NP replacement and has shown promise in vitro. This thesis aims to determine the effects of TMHA/EP composite augmentation on spinal motion segment mechanics in healthy and induced early stage DDD porcine intervertebral discs (IVD). Healthy IVD augmentation on average increased axial compressive stiffness, while bending and rotational stability decreased. Early stage DDD porcine IVD had compromised mechanical integrity in comparison to healthy controls. TMHA/EP augmentation of the mechanically compromised IVDs through two injection techniques worked to restore spinal stability, exhibiting mechanical properties similar to healthy IVDs. This work demonstrates the potential of the injectable TMHA/EP composite in providing initial structural stabilization in early stages of DDD.

Keywords: Nucleus Pulposus Replacement
Advisor: Whyne, Cari
Yee, Albert
Neural Mechanisms Underlying Bimanual Grasping

Grasping is fundamentally important for our successful interaction with the environment. Grasping with both hands is phylogenetically older than the hand yet its underlying mechanisms are poorly understood. The objective of this research is to examine bimanual grasping and its underlying mechanisms. Two experiments were conducted to examine whether bimanual grasping involves both hemispheres equally or only one dominant hemisphere, and to examine whether information crosses at an early visual level and/or at later sensorimotor/motor levels. The first experiment examined participants’ grasping and reaching movements while they fixated either to the left or right of the object. For the second experiment, EEG data was recorded while participants performed a similar task. The results from both experiments suggested that when we grasp an object with both hands, the left and right hemispheres control the action equally, and visual information is shared before it reaches areas that are involved in motor control.

Keywords: bimanual grasping
coordination
grasping
bimanual coordination
visual field
EEG
Advisor: Niemeier, Matthias
Internet Use among Occupational Therapists in their Clinical Practice

This study investigated the extent to which occupational therapists (OT) use the Internet as a clinical resource and as a tool for communication with clients. It also identified barriers and facilitators associated with Internet use. A survey was mailed to all occupational therapists registered with the College of Occupational Therapists of Ontario. Our findings based on 1382 respondents show that a large percentage of occupational therapists currently use the Internet for clinical purposes. A majority of respondents reported using the Internet to meet their practice needs, primarily for looking up relevant clinical information, and less commonly as a communication tool with their clients. Greater Internet use was associated with younger age and fewer years of practice. Having a computer station, a work culture fostering Internet use, accessible technical support, paid time and credible ratings of websites were five most influential factors on Internet use in OTs’ clinical practice.

Keywords: Internet use
occupational therapists
clinical practice
factors of Internet use
clinical resources
emails
survey study
Advisor: Colantonio, Angela
Development of a Test Platform and Control System to Demonstrate Autonomous Excavation for Space Exploration Applications

Increased interestin In-Situ Resource Utilization (ISRU) concept for lunar outpost construction has motivated to the development of autonomous excavation rovers. The system design of two autonomous excavation rover prototypes UNEMEEP and The Musketeers are detailed in this thesis. The problem of autonomous excavation has been explored in the area of agriculture and mining. However, to date very little have been accomplished in the area of an autonomous excavation rover aimed towards space application. A hybrid position and admittance control strategy is implemented on autonomous excavation rovers to achieve digging and leveling capabilities. Integration tests and a full scale multirover mission scenario were also carried out. The results from the experiments are analyzed and recommendations are made to improve upon the capabilities of the rovers.

Keywords: Excavation
Lunar
Autonomous
Rover
Bulldoze
Advisor: D'Eleuterio, Gabriele M. T.
Re-reading Translations in Wu Zhuoliu's Orphan of Asia

The author seeks to compare the Chinese and English editions of Wu Zhuoliu’s (1900-1976) Orphan of Asia (1956). Through the analysis of several characters and the political ambiguity within the text, the author first attempts to compare the two target translations of the original Japanese text. In addition to the close reading of the novel(s), the author employs paratextual analysis of the Chinese and English versions of the story in order to challenge the publishing practices of translation. The re-reading of translations thus includes an investigation of the content of the story as well as the packaging of the text. The objectives of this project include adding to the research completed on Wu’s canonical text, in translation studies, and in paratextual studies.

Keywords: Taiwanese Literature
Translation
Paratextual Analysis
Orphan of Asia
Wu Zhuoliu
Wu Choliu
Asia's Orphan
Advisor: Liu, Johanna Chien-mei
Wideband Plasmonic Slot-silicon Wire Coupling

An SOI-based platform designed for wideband coupling of light from optical fibers to a 50 nm wide plasmonic slot waveguide is described in this thesis. The device is based on a newly proposed orthogonal junction with coupling efficiencies above 70% near the telecom wavelength. To construct the coupling platform, two such junctions are utilized for input and output, where Si wires are place 90 degree with respect to each of the two ends of a plasmonic section. Analytic studies and FDTD simulations have demonstrated attractive properties such as a smooth micron-wide transmission spectrum that can be spectrally shifted with the design parameters, and the natural phase-matching between the dielectric and plasmonic sections consequent of the waveguide orientations. Fabrication procedures and proof-of-concept characterization work are also presented. The experimentally-tested platform with its unique features would enable applications in on-chip sensing and plasmonic slot-based waveguiding at the 50 nm scale.

Keywords: plasmonics
photonics
Advisor: Helmy, Amr S.
Characterizing the Organization within Alternative Lengthening of Telomere Associated-promyelocytic Leukemia Nuclear Bodies

In the absence of telomerase activity, a subset of cancerous and immortalized cells maintain telomere length by means of a poorly understood mechanism, termed alternative lengthening of telomeres (ALT). Many details of telomere maintenance in ALT positive cells remain unclear, but significant evidence implicates a homologous recombination mechanism. ALT specific nuclear structures, known as ALT-associated promyelocytic leukemia nuclear bodies (APBs), are thought to serve as the site of telomere extension. Using electron spectroscopic imaging we have demonstrated that APBs contain substantial amounts of nucleic acid sequestered within the bodies. In contrast, promyelocytic leukemia nuclear bodies in non-ALT cell lines contain no significant nucleic acid. We show that the nucleic acid found in APBs is not RNA and provide evidence that it is in fact telomeric repeat DNA. This evidence supports a role for APBs to sequester extrachromosomal telomeric DNA in order to suppress the activation of DNA repair.

Keywords: Alternative Lengthening of Telomeres
Promyelocytic Leukemia Nuclear Bodies
Electron Spectroscopic Imaging
Nuclear Organization
Advisor: Bazett-Jones, David
A Phage Display System to Profile the DNA-binding Specificities of C2H2 Zinc Fingers

Knowing the sequence specificities of transcription factors allows us to surmise their functions and establish their regulatory roles in genomes. The most common DNA-binding domain among eukaryotic transcription factors is the Cys2His2 zinc finger domain; however, despite their prevalence, the specificities of the majority of Cys2His2 zinc finger proteins remain unknown due to the difficulty in assaying them. My objective was to develop a new phage displayed-based assay, in which individual Cys2His2 domains are displayed on phage in an otherwise constant three-finger protein scaffold. In Chapter 2, I discuss evidence for the modularity of the Cys2His2 domain, since my assay requires that zinc fingers be modular. In Chapter 3, I describe my results on the development of this phage display-based assay. This work provides support for a new strategy to determine the specificities of individual zinc fingers, which can be used to infer specificities for multi-finger Cys2His2 proteins.

Keywords: C2H2
zinc fingers
phage display
modular
DNA-binding specificity
Advisor: Hughes, Timothy R.
PKC Signaling Regulates Drug Resistance of Candida albicans and Saccharomyces cerevisiae via Divergent Circuitry Composed of the MAPK Cascade, Calcineurin and Hsp90

Treating fungal infections is challenging due to the emergence of drug resistance and the limited number of clinically useful antifungal drugs. To improve clinical outcome it will be necessary to develop new antifungal drugs with different mechanisms of action and to discover drugs that improve the fungicidal activity of current antifungals. This study reveals a new role for fungal protein kinase C (PKC) signaling in resistance to drugs targeting the ergosterol biosynthesis pathway in the pathogenic fungus, Candida albicans, and the model yeast, Saccharomyces cerevisiae. PKC signaling enabled survival of antifungal-induced cell membrane stress in part through the mitogen-activated protein kinase (MAPK) cascade and through cross-talk with calcineurin signaling in both species. The molecular chaperone Hsp90, which stabilizes client proteins including calcineurin, also stabilized the terminal C. albicans MAPK, Mkc1. This establishes new circuitry connecting PKC with Hsp90 and calcineurin, and suggests that inhibiting fungal Pkc1 can be a promising strategy for treating life-threatening fungal infections.

Keywords: Protein Kinase C
Drug Resistance
Candida albicans
Saccharomyces cerevisiae
Hsp90
Calcineurin
Advisor: Cowen, Leah
Polarization Model and Control in Fiber-based Bidirectional Systems with Reflections

We present, for the first time, methods to model and control the polarization of the output lightwave of a bidirectional fiber-optic system, in which the lightwave propagates through polarization control elements in both directions. Using the dynamic eigenstate (DES) principle, we built model to simulate the behavior of the polarization evolution. In a bidirectional system with one control element, we extracted system parameters from experimental data and achieved less than 3% angular deviation between modeled and experimental state of polarization (SOP). The theory was further validated by varying the input SOP to the bidirectional system. Our method can be extended to predict the SOP of a system with multiple actuators. Furthermore, combining our deterministic control method and a feedback loop, we are able to control the output SOP to be within a mean angular deviation of 5.5% from the target SOP, with as few as three iterations.

Keywords: Fiber-optics
Polarization
Advisor: Qian, Li
Patentability of Signals in Canada

This paper addresses the question of whether the patentability of signals is compatible with the law in Canada and attempts to develop a test for use in determining when a signal should be considered patentable subject matter. The hard-line position of the Canadian Intellectual Property Office, that signals are not patentable, is shown not to be supported in law. Canada’s domestic law is, in fact, compatible with the patentability of signals. Lessons are drawn from Europe, where signals are patentable and the United States, where they are not. Various international treaties are also examined for possible obligations concerning signals. Finally, an attempt is made to formulate a workable test for the patentability of signals that is compatible with Canadian legislation and case law.

Keywords: patentable subject matter
signal
Advisor: Katz, Ariel
Differential Effects of PPAR-γ Activation vs. Chemical or Genetic Reduction of DPP-4 Activity on Murine Bone Quality

This study characterized the effects of two anti-diabetic drugs, a thiazolidinedione (TZD) and a Dipeptidyl Peptidase-4 (DPP-4) inhibitor on bone quality in a glucose intolerant mouse model. Bone quality in a DPP-4 -/- mouse model was also examined. Bone quality was evaluated through densitometry, mechanical testing and techniques to assess remodeling, structural and mineral properties. TZD treatment negatively affected trabecular mechanical properties in male, female and ovariectomized female (OVX) mice. Male mice exhibited the greatest effect due to TZD treatment with reduced vertebral vBMD, trabecular structure and bone formation. DPP-4 inhibitor treatment improved vertebral vBMD and trabecular architecture in female mice but improvements were lost in females following OVX. Male, female and OVX mice experienced increased trabecular mineralization due to DPP-4 inhibitor treatment. Genetic inactivation of DPP-4 did not produce a major bone phenotype in male and female mice but lead to reduced femoral geometry and mechanics in OVX mice.

Keywords: Bone Quality
Osteoporosis
Diabetes
Thiazolidinediones
DPP-4 Inhibitors
Advisor: Grynpas, Marc D.
Personality Foreshadows the Structure of Internalizing Disorders in Middle Childhood

The current investigation compared the fit of three models of internalizing in middle childhood: (1) a unitary factor model, (2) a two-factor model corresponding to the DSM-IV Anxiety/Depression distinction, and (3) a two-factor model corresponding to the Fear/Distress distinction observed in structural studies of adult psychopathology (Krueger, 1999; Slade & Watson, 2006). Mothers of 344 children (50.6% female, mean age = 9.97, SD = .82) reported on childhood internalizing symptoms and personality traits. Confirmatory factor analyses revealed acceptable fit indices for all three models. The unitary factor model provided the most parsimonious fit to the data. Although the structural analyses suggested that internalizing subfactors were not differentiated in middle childhood, hierarchical regression analyses revealed that personality dimensions uniquely predicted fear and distress disorders. These results suggest that personality foreshadows later psychopathology structure before it is manifest at the symptom level.

Keywords: developmental psychopathology
internalizing
personality
structural models
middle childhood
Advisor: Tackett, Jennifer L.
Dynamic Categorization: What We Can Learn from the Emergent Arrangement of Physical Artifacts in Libraries

Radio frequency identification (RFID) is a technology used in many applications for the identification of objects. This thesis presents a concept of how libraries could use RFID technology to locate physical items within the library. The ability to locate items within the library changes the way users interact with physical material, creates new ways of user collaboration, and influences the ability to browse the shelves for physical items. Several implementation scenarios are presented in detail and implications on collaboration and browsing are analyzed.

Keywords: Libraries
categorization
RFID
Radio Frequency Identification
browsing
folksonomies
retrieval
emergent
Advisor: Mai, Jens-Erik
Hockema, Stephen
The Functional Integration of Adult-born Granule Cells into Dentate Gyrus Circuitry

New neurons are generated throughout adulthood in the dentate gyrus of the hippocampus. The aim of the current study was to address whether differences in the morphological complexity of adult-born granule cells affect their integration into existing dentate gyrus circuitry. To selectively label proliferating cells, we injected a CAG-retrovirus into the dentate gyrus of mice. Either 10, 20, 40, or 80 days following viral infection, mice were injected with pentylenetetrazol (PTZ) to induce hippocampal activation, and expression of the immediate early gene c-fos was used as a marker of activated neurons. We then compared morphological features of neurons across age groups and between Fos+ and Fos- neurons within each age group. We found that dendritic length and branch number increased from 10 to 20 days post infection. Unexpectedly, we also found that dendritic length and branch number decreased from 20 to 40 days post infection, suggesting that the maturation of adult-generated neurons is associated with an active pruning process. Furthermore, we found no significant difference in morphological complexity between Fos+ and Fos- neurons, suggesting that dendritic morphology does not influence integration into dentate gyrus circuitry.

Keywords: neurogenesis
dentate gyrus
Advisor: Frankland, Paul
Forfeited: Civil Forfeiture and the Canadian Constitution

The enactment of civil asset forfeiture legislation by Alberta and Ontario in the fall of 2001, followed by the passage of similar legislation in five other provinces, has signalled a dramatic change in the way Canadian constitutional law ought to be understood. This thesis builds on American legal scholarship by highlighting how deficiencies in Canada’s constitutional law could create space for more invasive civil forfeiture statutes. Following a historical overview of forfeiture law in Canada, the thesis (i) examines how the Supreme Court of Canada mischaracterized this legislation as a matter of property and civil rights; (ii) considers whether the doctrine of federal paramountcy should have rendered the legislation inoperable and the consequences of the failure by the Court to do so; and (iii) evaluates iiithe impact of the absence of an entrenched property right in the constitution, in regard to this matter.

Keywords: Constitutional Law
Criminal Law
Forfeiture
Charter
Constitution Act, 1867
Division of Powers
Paramountcy
Property
Advisor: Weinrib, Lorraine