VictorJuiz/thesis huggingface dataset:
Deuterium Retention in Polycrystalline Tungsten
Keywords: deuterium
polycrystalline tungsten
retention

Deuterium retention in two types of polycrystalline tungsten was studied as a function of ion fluence, irradiation temperature and ion energy. Fluence dependence: D retention at 300 K tends to saturate in both Rembar and Plansee PCW. At 500 K, D retention in the Plansee PCW increases with increasing ion fluence, similar to previous results for Rembar tungsten. Even at a fluence of 8×10^25 D+/m2, no sign of saturation was observed. Temperature dependence: D retention in Plansee PCW decreases with increasing irradiation temperature (300 - 500 K). Energy dependence: varying the D+ energy from 100 to 500 eV/D+ plays a minor role in D retention in W, suggesting that D retention depends more on the W structure, irradiation temperature and fluence, rather than on the ion energy when the energy is below the displacement threshold.
Do Moral Action and Moral Prediction Go Hand in Hand? Exploring Morality as a Function of Self-regulation
Keywords: Morality
Self-regulation

Psychologists have long been directing their energy to the domain of moral judgment or moral prediction, assuming that when extended to moral behaviour, results will prove consistent. The aim of this research was to explore the dissociation between moral prediction and moral behaviour. Pilot research suggests that people expect others to act less morally than they say they would. The results of two experiments, however, suggest the opposite. In both studies, participants were assigned to either a moral action condition, where they were placed in a moral dilemma, or a moral prediction condition, in which they had to predict their behavior in that dilemma. In Study 1, the Dictator Game was used to measure morality, whereas in Study 2, cheating behaviour was measured. In both experiments, participants acted more morally than they predicted they would. This research has implications for scrutinizing the applicability of previous work on moral self-prediction.
Insulin Sensitivity is Enhanced by CGMP-mediated MAPK Inhibition in Rat Adipocytes
Keywords: ANP
insulin resistance
bradykinin
diabetes
MAPK
AKT
PKB
cGMP
PKG

Bradykinin (BK) acts through eNOS to reduce MAPK-mediated feedback inhibition of insulin signalling. Preliminary data suggest that the sGC-cGMP-PKG pathway, a prominent NO target, is involved. Our present study aimed to support the role of this pathway with atrial natriuretic peptide (ANP), which uses a receptor associated GC (NPR-A) to generate cGMP. We found that treating adipocytes with ANP mimicked BK effects on insulin-stimulated glucose uptake, Tyr-IRS-1 and Akt/PKB phosphorylation, as well as JNK and ERK1/2 inhibition. These outcomes depended on GC-cGMP-PKG signalling since A71915 (NPR-A antagonist), and KT-5823 (PKG inhibitor), completely abrogated them, while zaprinast (phosphodiesterase inhibitor), prolonged ANP actions. Furthermore, decreased MAPK phosphorylation was independent of upstream kinase activity, suggesting that MAPK phosphatases may be involved. These data indicate that BK and ANP act through the GC-cGMP-PKG pathway to potentiate insulin signalling via attenuated feedback inhibition. Stimulating the GC-cGMP-PKG pathway may, therefore, be a promising therapy for T2DM.
Characterizing the Role of RGS5 in the Regulation of Vascular Smooth Muscle Cell Function
Keywords: G-Protein
Vascular

Regulators of G-protein signaling (RGS) modulate G-protein coupled receptor (GPCR) activity in vascular smooth muscle cells (VSMCs). One such protein, RGS5, has been shown to have selective expression in VSMCs and pericytes, and can inhibit signaling from Gαq and Gαi subunits. Using an RGS5 knockout model, we assessed the functional effect of RGS5 in the constriction and dilation of resistance arterioles. Furthermore, we examined the intracellular lipid interaction of RGS proteins to identify the determinants regulating the biologic function of RGS5. Surprisingly, loss of RGS5 function in mesenteric arterioles had no effect on constriction and dilation of resistance arterioles. Cultured VSMCs showed increased basal ERK1/2 phosphorylation and increased VASP signaling in response to SNP treatment in RGS5KO VSMCs as compared to wild type controls, with no effect on cell proliferation. These data suggest RGS5 may integrate multiple intracellular pathways with competing effects on VSMC contraction.
Analysis of Lead Monitoring Data in Drinking Water
Keywords: 0543

Historical lead in tap water data from the City of London and the City of Ottawa were examined for trends and correlations over time. Factors such as the sampling protocol, temperature, and pH were analyzed to determine their specific impacts on lead. Linear and logistic regression models were also developed to predict lead concentrations in tap water based on different water quality parameters. Finally, a physical mass transfer and flow model (zonal model) was validated with the lead data from the two municipalities. Results indicate the potential use of the regression and zonal models to predict a range of lead concentrations for a number of homes in a Canadian city based on the field data. These methods may allow municipalities to determine the impact of a corrosion control strategy such as a pH increase without having to sample for lead in people's homes.
Quantitative Characterization of Natural Rock Discontinuity Roughness In-situ and in the Laboratory
Keywords: Discontinuity roughness
Rock engineering
Scale effects
Geomechanics
Rock mechanics
Discontinuity shear strength

The surface roughness of unfilled rock discontinuities has a major influence on the hydro-mechanical behaviour of discontinuous rock masses. Although it is widely recognized that surface roughness is comprised of large-scale (waviness) and small-scale (unevenness) components, most investigations of surface roughness have been restricted to small fracture surfaces (<1m2). Hence, the large-scale components of roughness are often neglected. Furthermore, these investigations typically define roughness using two-dimensional profiles rather than three-dimensional surfaces, which can lead to biased estimates of roughness. These limitations have led to some contradictory findings regarding roughness scale effects. This thesis aims to resolve some of these issues. The main findings indicate that discontinuity roughness increases as a function of the sampling window size contrary to what is commonly assumed. More importantly, it is shown that the estimated roughness significantly decreases as the resolution of surface measurements decrease, which could lead to the under estimations of roughness and, consequently, discontinuity shear strength.
The Effects of Stress and Placebo Alcohol on Cognitive Activation and Inhibitory Control in Male Problem Drinkers and Healthy Controls
Keywords: clinical pharmacology
problem drinkers
addiction

This study assessed the separate and combined effects of two important instigators of relapse, alcohol cues and stress, on the salience of alcohol target stimuli and inhibitory control, in 12 male problem drinkers and 16 male controls. Subjects underwent two test sessions where they received alcohol cues (non-alcoholic beer) and/or stress (uncontrollable noise) in a counterbalanced manner. Testing was carried out through validated, computer-based tasks: modified Stroop, gambling-word Shift task; and conventional and modified (Alcohol word) Stop-Signal tasks. Inhibitory control was preferentially impaired to Alcohol stimuli in both groups. Beer and stress in combination increased incentive salience of Alcohol stimuli and moderated self-reported desire for alcohol in problem drinkers but not controls. Results suggest that alcohol cues and stress have interactive effects on subjective motivation, and disinhibit behaviour due to distraction in problem drinkers. Findings from this paradigm may improve understanding and facilitate treatment for relapse prevention in problem drinkers.
Preoperative Carbohydrate Loading in Patients Undergoing Coronary Artery Bypass or Spinal Surgery
Keywords: Insulin resistance
Carbohydrate supplementation
Cardiac surgery
Spine surgery
Short insulin tolerance test
Outcomes

Patients undergoing elective surgery typically fast for 8-12 hours before surgery. However, oral preoperative carbohydrate ingestion may increase postoperative insulin sensitivity and reduce complications. To determine the effects of carbohydrate supplementation prior to CABG or spinal surgery, 38 patients were randomized to receive a carbohydrate supplement or to fast for 12 hours preoperatively. Baseline and postoperative measurements of insulin sensitivity were completed using the short insulin tolerance test and homeostasis model assessment (HOMA). Patient discomfort was measured immediately before surgery. Insulin sensitivity was not significantly different between groups. However, the supplemented group experienced a significantly smaller rise in glucose levels following surgery (p=0.03) and had higher postoperative HOMA-β scores (p=0.02). Fasted patients were significantly more thirsty (p=0.01), hungry (p=0.04) and anxious (p=0.01) before surgery and experienced a significantly longer hospital stay (p=0.008). Carbohydrate supplementation improved outcomes, warranting re-evaluation of fasting practices prior to major surgery.
Does Inulin Reduce Postprandial Free Fatty Acid Rebound?
Keywords: free fatty acids
short chain fatty acids
inulin

High fibre diets are associated with reduced risk of type 2 diabetes mellitus (T2DM). This may be due to short-chain-fatty-acids (SCFA) influencing insulin resistance and secretion via changes in free-fatty-acids (FFA) and specific gut hormones. We aimed to determine the postprandial effects of inulin, a fermentable, soluble fibre in healthy subjects. Twelve fasted subjects were studied for 6 hours after either 80g high fructose corn syrup (HFCS), 56g HFCS plus 24g inulin, or 56g HFCS drinks using a randomized, cross-over design. SCFA were higher after inulin beginning at 4 hours. FFA were lower 4 hours after inulin than 56gHFCS. GLP-1 was higher 30 minutes after inulin than 56 and 80HFCS, while ghrelin was lower from 4-6 hours after inulin. The results support the hypothesis that inulin and SCFA generated from colonic fermentation of dietary fibre may improve insulin resistance and secretion via modulation of FFA and specific gut hormones.
Programmed Cell Death 4 is a Direct Target of miR-21 and Regulates Invasion in Oral Squamous Cell Carcinoma
Keywords: Oral Cancer
PDCD4
miR-21
Metastasis
Invasion
Biomarkers

Programmed Cell Death 4 (PDCD4) is a known tumour suppressor, lost in carcinomas of the breast, prostate, colon, lung and ovary. This study found significantly reduced levels of PDCD4 mRNA and protein in both primary patient oral squamous cell carcinomas (OSCCs) and OSCC cell lines. Moreover, lower PDCD4 mRNA levels were significantly correlated with nodal metastasis (P=0.019). To determine the functional significance of PDCD4 down-regulation in OSCC we asked whether PDCD4 played a role in invasion. In fact, over-expression of PDCD4 decreased invasion of OSCC lines. We then sought to determine a mechanism for PDCD4 down-regulation in OSCC. Previous studies in breast and colon carcinomas suggested that reduced PDCD4 expression was due to over-expression of miR-21. Interestingly, miR-21 was inversely correlated to PDCD4 mRNA (P=0.002) and PDCD4 protein (P<0.001) levels in OSCC patient samples. Moreover, we found that miR-21 directly regulated PDCD4 protein expression in OSCC cell lines. This is the first report in OSCC that demonstrates that PDCD4 is down-regulated by miR-21 and may play a role in OSCC invasion.
Permafrost in Canada's Subarctic Region of Northern Ontario
Keywords: Permafrost
Palsa
Stefan Depth
Active Layer
Degree Days
Northern Ontario

An investigation of permafrost (permanently frozen soil) was conducted in Canada’s subarctic region of Northern Ontario. Environmental baseline conditions and permafrost states were estimated using seasonal freezing and thawing energies based on observed climate data and the Stefan equation. Field studies provided measurements of the active layer depths and validated the permafrost states; laboratory studies of the soil samples provided characterization for organic materials that have high affinity for soil moisture. Palsas (unique dome-like formations) were observed to have enhanced permafrost cores beneath a thermal insulating organic layer. With climate change, results suggest the possibility of shifts from the classification of continuous to discontinuous permafrost states in areas lacking the presence of organic materials that can have environmental and ecological impacts. Northern infrastructures may become destabilized with the degradation of permafrost while palsas may become lone permafrost refuges for biodiversity that depend on cooler ecosystems, such as polar bears.
A Substantive Void: Dependency, Conditionality, and Deformalization of the International Law of Self-determination in the Case of Palestine
Keywords: international law of self-determination
Colonialism and the mandate system
conditionality in international law
Self-determination in the Occupied Palestinian Territories

Be it the Algerian National Liberation Front, the African National Congress in South Africa or the continued struggle of the Palestinian people, the principle of self-determination is largely central to all projects of national liberation. This paper addresses what is arguably a deficient conception of self-determination by highlighting two factors that contributed to this deficiency. The first is the re-enforcement of dependency in self-determination projects by international institutions, primarily through the Mandate System. The second is a merit-based system of conditionality for the granting of independence, accompanied by a tendency to deformalize the law, relegating self-determination to an empty principle, the substance of which is decided by the negotiations’ context. The case of Palestine is used to demonstrate how those factors are adopted as central means in resolving the Palestinian self-determination problem, which in-turn leads to a deficient conception that does not account for the core content of the right.
Genetic and Serolgical Markers Associated with Pouchitis and a Crohn's Disease-like Phenotype after Pelvic Pouch Surgery for Ulcerative Colitis
Keywords: serological
genetic

Objective: Study the clinical, genetic and serological factors associated with new onset ileal inflammation in ulcerative colitis (UC) patients who have undergone ileal pouch-anal anastomosis (IPAA). Methods: Retrospective assessment of UC patients registered in the MSH surgical database, questionnaire, chart review and serological and genetic analysis of blood sample. Results: There was a positive association between gASCA antibodies, anti-L, smoking status and axial arthritis/ankylosing spondylits with a Crohn’s Disease (CD)-like phenotype post-op in UC/IPAA patients. Associations between alleles of selected genes including ECM1, PTPN2, and CD14 and post-operative phenotype were identified. Conclusions: gASCA is typically associated with CD rather than UC which raises the possibility that gASCA positivity may delineate a subset of UC patients at risk for developing a CD-like phenotype after IPAA. The identification of genotype/phenotype associations in UC/IPAA will help to find those at risk for poor post-operative outcome. Prospective studies are needed to confirm these findings.
Interconnection of Direct-drive Wind Turbines Using A Series Connected DC Grid
Keywords: HVDC power transmission
wind energy
offshore wind farms
power electronics

This thesis presents the concept of a "distributed HVDC converter" for offshore wind farms. The proposed converter topology allows series interconnection of wind turbines obviating the necessity of transformers and an offshore platform. Each wind turbine is equipped with a 5MW permanent-magnet synchronous generator and an ac-dc-dc converter. The converter topology is a diode rectifier (ac-dc) cascaded with a single-switch step-down converter (dc-dc). The dc-dc stage allows the current to flow at all times in the dc link while regulating generator torque. The receiving end is equipped with a conventional thyristor-based HVDC converter. The inverter station is located onshore and it regulates the dc link current to be constant. Stability of the configuration and independent operation of the wind turbines are validated through simulations using the PSCAD/EMTDC software package. Protection for some key dc fault scenarios are discussed and a possible protection strategy is proposed.
Hypoxia-induced Decrease in Renal Medullary Osmolality: Prevention with dDAVP
Keywords: hypoxia
renal function
dDAVP
osmolality

Acute kidney injury (AKI) may result from perioperative renal medullary hypoxia. Despite high oxygen delivery to the kidney, the medullary thick ascending limb (mTAL) in the outer renal medulla is susceptible to hypoxia because of its high oxygen consumption and relatively low rate of blood flow. The objective of this study was to evaluate the effect of a low pO2 (8% FiO2 for 5 h) on the major function of the mTAL and to develop a strategy to protect the mTAL in this setting. Evidence of hypoxia-induced reduction in mTAL function included low interstitial and urine osmolality but only a minimal rise in Na+ excretion; this was prevented by pre-treatment with desmopressin acetate (dDAVP), a vasopressin analogue which may increase tissue pO2. A decrease in urine osmolality may be of diagnostic value for hypoxic renal damage and dDAVP may prevent acute kidney injury in the perioperative setting.
State-dependent Versus Central Motor Effects of Ethanol on Breathing
Keywords: sleep
breathing
genioglossus muscle
ethanol
hypoglossal motor nucleus
microdialysis

This thesis tested the hypothesis that ethanol suppresses respiratory muscle activity by effects at the central motor pool and/or by state-dependent regulation of motor activity via influences on sleep/arousal processes. Ten rats were implanted with electroencephalogram and neck electrodes to record sleep-wake states, and genioglossus and diaphragm electrodes for respiratory recordings. Studies were performed following intraperitoneal injection of ethanol (1.25g/kg) or vehicle. The effects on genioglossus activity of ethanol (0.025-1M) or vehicle applied directly to the hypoglossal motor nucleus were also determined in sixteen isoflurane-anaesthetized rats. The results of these studies suggest that ethanol at physiologically relevant concentrations promoted sleep, and altered electroencephalogram and postural motor activities indicative of a sedating effect. The lack of effect on genioglossus activity with ethanol applied directly to the hypoglossal motor pool suggests that the suppression observed with systemic administration may be mediated via effects on state-dependent processes rather than direct effects at the motor pool per se.
The Investigation and Development of Mechanical Resonance Tissue Analysis and the Relationship to Dual Energy X-ray Absorptiometry and Quantitative Ultrasound
Keywords: Bone
Quality
Strength
Ulna
MRTA

Currently Dual energy X-ray Absorptiometry (DXA) and Quantitative Ultrasound (QUS) are used readily in the clinical environment for the assessment of bone quality. However, neither measure is a direct mechanical measure of bone. A Mechanical Resonance Tissue Analyzer (MRTA) has been developed that looks at the ulna’s deformation curve to vibration to achieve the measure of EI, cross sectional bending stiffness. This study investigated the relationships between MRTA to that of QUS and DXA. Regression analysis found significant linear correlations between EI to BMD and BMC, however, no significant relationships were found between EI and the variables of QUS. However, this technology is seen to have a potential for the assessment of in vivo bone quality. Furthermore, an improved configuration of the MRTA device is described, in addition to how preliminary results correspond to theoretical results.
Display Design and Intelligent Automation: Design of an Intelligent Water Monitor Display
Keywords: automation
display design
Ecological Interface Design
Cognitive Work Analysis
water monitoring
intelligent automation
usability

In response to growing concerns over the susceptibility of water distribution systems to contamination, this thesis presents the design and evaluation of an ecological display for an intelligent water monitoring system. Work Domain Analysis and Control Task Analysis were used to uncover the information requirements of the display. The work domain model in this thesis is one of a limited number of such models to include a representation of the automation. The resulting ecological display was evaluated in a comparative usability study against an alternative display based on a competitor’s product. Nine certified water operators participated. The displays were compared across three categories of usability measures: effectiveness, efficiency, and satisfaction. No significant differences were observed. The results, however, helped identify design changes for the display. The implications for the design of intelligent automation displays, and the challenge of designing displays in parallel with early development of automation systems, are discussed.
The Effect of Sodium Doping on Calcium Polyphosphate
Keywords: calcium polyphosphate
sodium

Calcium polyphosphate (CPP) is a suitable substrate in a novel tissue-engineering strategy. The strategy aims to culture articular cartilage in vitro onto porous CPP and then implant the biphasic construct into the joint to replace damaged cartilage. CPP substrates should degrade faster to enhance repair. This project examined the structural and degradation effects of doping CPP with sodium phosphate, sodium hydroxide, and sodium carbonate. Doping concentration was narrowed to 0.01 Na2O/CaO for comparable phase composition to pure CPP. All doped groups sintered and crystallized at lower temperatures than pure CPP. Hydroxide-doped CPP did not form adequate sinter necks. At similar open porosity, Phosphate-doped CPP had similar diametral strength than pure CPP, while Carbonate-doped CPP had greater diametral strength. Degradation in vitro showed that Phosphate-doped CPP had greater strength loss, while Carbonate-doped CPP had similar strength loss, compared to pure CPP. Both doped groups degraded more slowly than pure CPP.
Clonal Derivation of Neural Stem Cells from Human Embryonic Stem Cells
Keywords: neural
stem cell
human
embryonic
clonal

Clonal culture is crucial for experimental protocols that require growth or selection of pure populations of cells. Currently, there is no method for deriving neural stem cells (NSCs) clonally from single human embryonic stem cells (hESCs). Bulk derivation of neural progenitors from hESCs for cell therapies can lead to a host of problems including incomplete differentiation leading to proliferation of tumorigenic clusters in vivo. Clonal derivation allows for the screening and selection of only the most suitable cells for culture and expansion. We have developed a clonal, serum free method of generating NSCs and their progenitors directly from hESCs with an efficiency of 1.6%. The NSC colony-forming cell was identified as a TRA-1-60-/SSEA4- cell whose fate becomes specified in maintenance conditions by inhibition of bone morphogenic protein (BMP) signalling. This clonal culture method can be scaled up to produce vast quantities of NSCs for differentiation and use in cell therapies.