VictorJuiz/thesis huggingface dataset:
The Use of Endothelial Progenitor Cells to Promote Bone Healing in a Defect Model in the Rat Femur
Keywords: Fracture Healing
Endothelial Progenitor Cells (EPC)

The objective of this project was to evaluate the effects of local endothelial progenitor cell (EPC) therapy on bone regeneration in a segmental defect in the rat femur. Animals from the EPC-treated (N=28) and control (N=28) groups were sacrificed at 1, 2, 3, and 10 weeks post-operatively. Bone healing was evaluated with radiographic, histological, and micro computed tomography (micro-CT) scans. Radiographically; mean scores of the EPC group at 1, 2, and 3 weeks were significantly higher compared to control group. At 10 weeks, all the animals in the EPC group had complete union (7/7), but in the control group none achieved union (0/7). Histologically, specimens from EPC-treated animals had abundant new bone formation compared to controls. Micro-CT assessment showed significantly improved parameters of bone healing for the EPC group compared to control group. In conclusion, local EPC therapy significantly enhanced bone regeneration in a segmental bone defect in rat femur.
Understanding the Adsorption of Polycyclic Aromatic Hydrocarbons from Aqueous Phase onto Activated Carbon
Keywords: polycyclic aromatic hydrocarbons
adsorption
activated carbon
kinetics
equilibrium
mechanism

Non-competitive adsorption of polycyclic aromatic hydrocarbons (PAHs) from water onto activated carbon was studied alongside the performance of CO2-activated petroleum coke as a low-cost adsorbent. PAH adsorption was a two-stage process: a short, fast initial period followed by a long, slow period corresponding to the intra-particle diffusion of PAH molecules in macropores and micropores. The adsorption capacity was determined by total surface area accessible to PAH and the availability of active surface chemical groups. The positive dependence of adsorption capacity on surface oxygen groups and temperature was observed, suggesting a chemical nature of PAH adsorption. The interaction between PAH-activated carbon was however, weak and energetically similar to that of hydrogen bonds. Overall, PAH adsorption was an exothermic process that combined physisorption and chemisorption. CO2-activated petroleum coke had a greater SSA-normalized capacity than coal-derived commercial activated carbon (0.26 vs. 0.19 mg/m2). The capacity was significantly increased by post-oxidation to 0.62 mg/m2.
Chinese Influence on the African “Resource Curse”
Keywords: Mining
Institutions

This thesis explores the impact that Chinese aid and investment has on the political economy of resource-rich African countries. In particular, it examines the effects of Chinese resource-for-infrastructure agreements on the political economy of the resource curse. Using Ghana as a case study, this thesis highlights the peculiar obstacles that countries face with regard to managing their resources. In turn, it argues that general prescriptions against the resource curse, such as resource revenue transparency initiatives, like the Extractive Industries Transparency Initiative, are insufficient. As a result, African recipients of Chinese aid require specific institutional arrangements that accurately reflect the specific “rules of the game” that exist under their respective political economies. In the case of Ghana, this thesis argues that vetting Chinese resource-for-infrastructure agreements through the Public Procurement Act serves that need.
A Time-varying Feedback Approach to Reach Control on a Simplex
Keywords: control
feedback
affine
reach control
simplex
flow
invariance condition
equilibria
M-matrix

This thesis studies the Reach Control Problem (RCP) for affine systems defined on simplices. The thesis focuses on cases when it is known that the problem is not solvable by continuous state feedback. Previous work has proposed (discontinuous) piecewise affine feedback to resolve the gap between solvability by open-loop controls and solvability by feedbacks. The first results on solvability by time-varying feedback are presented. Time-varying feedback has the advantage to be more robust to measurement errors circumventing problems of discontinuous controllers. The results are theoretically appealing in light of the strong analogies with the theory of stabilization for linear control systems. The method is shown to solve RCP for all cases in the literature where continuous state feedback fails, provided it is solvable by open loop control. Textbook examples are provided. The motivation for studying RCP and its relevance to complex control specifications is illustrated using a material transfer system.
The Effects of Memory Remoteness on Recall and Recognition: Development of a Novel Measure of Naturalistic Memory
Keywords: Naturalistic memory
Recognition memory

The current study introduced a new measure for the study of naturalistic memory, which involved the use of a homogeneous, controlled event for all participants. We tested participants’ memory for this so-called staged event with both the Autobiographical Interview (AI) and our novel receiver operating characteristic (ROC) task. Statistical analyses indicated that scores on the AI and on our new ROC measure showed time sensitivity consistent with the literature. These data were difficult to interpret, however, because of a confound of age. We will need to age-match our groups before drawing any major conclusions. That said, we found a significant positive correlation between measures of recollection on both the AI and ROC task, which was a promising finding in terms of validating the new measure against an established procedure. Overall, our results suggest that assessing recall and recognition for a staged event is a viable method for studying naturalistic memory.
The Role of CD40L and CD40 in the Pathogenesis of Kawasaki Disease
Keywords: Kawasaki Disease
CD154
CD40L
Platelet
CD40
Superantigen

Kawasaki Disease (KD) is a childhood disease leading to coronary arteritis. Elevated numbers of CD40L+ platelets in circulation is correlated with risk of heart damage. CD40L is a tumor necrosis family member that binds to CD40 and αIIbβ3, receptors which are also expressed on platelets. A single injection of Lactobacillus casei Cell Wall Extract (LCWE) induces a disease similar to KD in mice, where LCWE superantigen (SAg) reactive T-cells persist in the coronary artery. This phenotype is inconsistent with the fate of SAg-stimulated cells and is likely mediated by co-stimulation. This work shows that stimulation with a SAg induces platelet activation and CD40L expression in vitro. Furthermore, enhanced survival of SAg-reactive T-cells is demonstrated following antibody-mediated CD40L cross-linking. This effect is mediated via inhibition of the extrinsic apoptosis pathway. In addition, CD40 cross-linking is also reported to enhance SAg-reactive T-cell survival by enhancing CD86 expression on APCs and CD28 co-stimulation.
Characterization of Executive Dysfunction in Real World Tasks: Analysis of Behaviours Performed during Completion of the Multiple Errands Test
Keywords: Rehabilitation
Stroke
Multiple Errands Test
Assessment
Executive Dysfunction
Event Recording

This study furthers our understanding of the impact of executive dysfunction on everyday activities in stroke survivors. A classification system was developed to analyze a wide range of behaviours performed by 14 stroke survivors and 12 matched controls on the Baycrest Multiple Errands Test, a task requiring participants to buy specific items and collect certain information on the main floor of the hospital. The event recorder was used to code the occurrences and frequencies of behaviours performed by participants. Results demonstrated that participants with stroke performed significantly more task specific relevant inefficient behaviours (p < .05) and non-task specific irrelevant behaviours (p < .10) compared to controls. This study indicates the importance of performing a detailed analysis of behaviours performed to better understand the impact of ED in everyday life.
High Speed Clock and Data Recovery Techniques
Keywords: CDR
Burst-Mode receiver
equalization
adaptation
ADC-based Receiver
Blind Sampling
CMOS
PON

This thesis presents two contributions in the area of high speed clock and data recovery systems. These contributions are focused on the fast phase recovery and adaptive equalization techniques. The first contribution of this thesis is an adaptive engine for a 2x blind sampling receiver. The proposed adaptation engine is able to find the phase-dependent DFE coefficients of the receiver on the fly. The second contribution is a burst-mode clock and data recovery architecture which uses an analog phase interpolator. The proposed burst-mode CDR is capable of locking to the first data transition it receives. The phase interpolator uses the inherent timing information in the data transition to rotate the phase of a reference clock and align it with the incoming data edge. The feasibility of the concept is demonstrated through fabrication and measurements.
The Effects of Hyperbaric Oxygen Therapy on Bone Distant from Site of Surgery
Keywords: Hyperbaric
Bone

Background: Hyperbaric Oxygen Therapy (HBOT) is used to promote soft and hard tissue repair at sites of injury or disease. It is not known whether it has any effect on uninjured tissues. Objective: To evaluate the effect of HBO on vertebral bones distant from a calvarial surgical site. Materials and Methods: 22 male New Zealand white rabbits were divided into two groups (n=11). All animals underwent surgery to produce bilateral calvarial critical sized defects. Group 1 received HBOT while Group 2 served as controls breathing room air (NBO). The Marx HBO protocol was used (90min, 100% oxygen at 2.4 ATA, 5 days a week for 4 weeks). Subjects were sacrificed at 6 weeks. The vertebrae were analyzed by micro-CT (μCT) and histology. Results: There were no statistical significant differences between the two groups. Conclusion: we concluded that there were no harmful effects of HBOT on non-injured vertebrae at 6 weeks.
Validation of Road Safety Surrogate Measures as a Predictor of Crash Frequency Rates on a Large-scale Microsimulation Network
Keywords: traffic conflict
microsimulation
crash frequency
road safety
SSAM

A study was done to explore the suitability of intersection and arterial collision prediction models based on traffic conflicts, generated using the Paramics microsimulation suite and the Surrogate Safety Assessment Model (SSAM). A linear regression model and a generalized linear model with a negative binomial error structure were explored to correlate conflicts to crash rates, as well as the conflict-based models suggested by SSAM. The model predictions were compared to volume-based predictions and historical data from Toronto, Ontario, Canada. The volume- based predictions were calculated using a negative binomial generalized linear model, fitted to the same arterial and intersection sets used to fit the conflict-based models. The results show the predictions generated by a conflict-based model were comparable for intersections, but poor for arterials.
Kuwait and Bahrain’s Anti-terrorism Laws in Comparative and International Perspective
Keywords: Anti-terrorism

Counter terrorism is one of the contemporary issues that concerns both the international community and Arab states. A problematic issue in this regard is the lack of a definition, which allows states to criminalize “terrorism” based on the best interest of each individual state. This thesis examines the laws that deal with terrorism in Kuwait, which rely on Kuwait’s broad national security laws. Problems with these laws include the lack of the rule of law and violation of human rights. This thesis highlights Bahrain’s experience with counter terrorism and the human right violation during the February 2011 revolution. The thesis emphasises the importance of having an appropriate definition that coincides with the rule of law and human rights, by adhering to the international guidance provided by the 1999 ‘International Convention on Suppression of Terrorism Financing’ and the UN Security Council Resolution 1566 (2004) as a first serious step in combating terrorism.
Role of Acculturation, Social Capital and Oral Health Literacy on Access to Dental Care among Preschool Children of Arabic-speaking Immigrants in Toronto, Canada
Keywords: access to dental care
immigrants
acculturation
social capital
oral health literacy
oral health knowledge

Objectives: To determine access to dental care among preschool children of Arabic-speaking immigrant families; to investigate the influence of social and cultural factors on access to dental care; and to measure preschool children’s oral health as reported by their parents. Methods: This survey used a semi-structured questionnaire to interview 100 Arabic-speaking parents of children under the age of 5 who were identified from community centres. Five scales were used to measure acculturation, social capital, oral health literacy, oral health knowledge, and health literacy. Results: Only 34% of families had visited the dentist to obtain dental care for their preschool children. Nineteen-percent of Arabic parents in our sample rated their children’s oral health as being fair or poor. None of the scales used in this study had a significant impact on access to dental care; however, higher scores on these scales tended to be associated with better access to dental care.
The Role of 4-1BB in Kawasaki Disease
Keywords: Kawasaki Disease
superantigen
T-cell
costimulation

Kawasaki disease (KD) is a multisystem vasculitis with predilection for the coronary arteries. Although the cause of KD remains elusive, there is evidence to suggest a superantigenic trigger. When T-cells are activated by a superantigen (SAg) they undergo massive proliferation but eventually apoptose; however, in KD, we hypothesize that these T-cells persist and infiltrate the coronary arteries. Previous studies have shown that enhanced costimulation through CD28 or 4-1BB rescues T-cells from apoptosis and exacerbates disease in a mouse model of KD. Our results suggest that this signal needs to be initiated close in timing to that of the SAg. In addition, the two molecules can act independently of one another, but are not additive. Also, stimulation of the 4-1BB pathway in the presence of a SAg elicits a Th1 phenotype. Lastly, TRAF1 regulates this enhanced survival downstream of 4-1BB. Thus, these results provide new insights into the effects of costimulation in SAg-mediated disease, and suggest that these pathways need to be targeted early to abrogate the enhanced survival of SAg-activated T-cells.
Information and Decision-making Processes Leading to Corporate Failure: Enron and Red Flags
Keywords: information processes
decision-making processes

Enron is examined as a critical case study to understand the role of information in the Enron’s Board’s decision-making processes. Three major events in the Enron failure were analyzed in detail using thematic analysis. Three themes were identified regarding the communication and use of information in Enron: interdependency of authority relationships, information control, and decision protocol and policies that shaped the information that management sent to the Board during the approval process. The Board was dependent on advisors to provide approvals first, prior to Board approval. The relationships between advisors and management influenced the information sent to the Board and affected controls used to monitor deals. The Board maintained that they were unaware of red flags, such as warnings related to incomplete disclosures and conflict of interest issues. The Board received information for arrangements which required Board approval but it had limited access to information regarding Enron’s operations.
Changes in Extreme Temperature Trends in the Greater Toronto Area from 1971 to 2000
Keywords: Extreme
Temperature

The impacts of extreme temperatures on human health and morbidity have been well documented in many studies. In literature, changes in the trends of extreme temperatures have been studied using percentiles, indicators and climate modeling. The aim of this study is to determine if the trend exhibited in the literature of statistically significant increases in extreme minimum temperatures, is also exhibited in the Greater Toronto Area during the 1971 to 2000 timeframe. A methodological approach using counts is the basis for the analysis. Statistical significance is determined through the use of Spearman’s Rank, Kendal-Tau and T-tests. A total of five stations are analysed, three being urban and two representing the surrounding suburban areas. The results indicate that statistically significant decline in extreme minimum temperature counts have occurred. In agreement with the literature, statistically significant increases in extreme maximum temperature counts can not be determined.
Identification of Novel Genes Critical for CNS Regeneration in L. stagnalis
Keywords: Invertebrate
Regeneration

Neuronal regeneration in the mammalian central nervous system (CNS) is severely compromised due to the presence of extrinsic inhibitory signals and a reduced intrinsic regenerative capacity. Understanding the cellular and molecular processes underlying injury and regeneration in the CNS is necessary for the development of effective therapeutic strategies. Lymnaea stagnalis, a freshwater pond snail, has proven to be a powerful model for studying the fundamental mechanisms underlying neurite outgrowth and regeneration. In this study I designed the first custom L. stagnalis microarray gene chip and carried out microarray analysis to profile gene expression changes following CNS injury. From a pool of significantly regulated genes, I provided the first evidence that C/EBP, a transcription factor, plays an integral role in regeneration by maintaining the viability of the distal neurite. We also proposed a novel signaling network and demonstrated that BCL 7 regulates neurite regeneration, an effect that may be mediated through Ca2+-dependent growth cone formation.
The Role of Neck Muscles Afferentation in Planning and Online Control of Goal-directed Movement
Keywords: upper limb reaching
neck proprioception
muscle vibration
movement control
frames of reference

Head position signal is crucial for preparing reaching movements because it contributes to specifying the position of body and target in space and relative to each other. However, it is unclear whether sensory information pertaining head position is used to control the movement after movement onset. In this study, nineteen participants performed discrete reaches towards a virtual target while neck vibration was randomly applied before and/or during the movement or not at all. The main dependent variable was the directional bias of the reaching finger. Neck vibration induced early leftward or late rightward trajectory biases. It appears that participants interpreted the sensed head shift as a target or an eye-in-head motion, which can be explained by individual differences in the use of reference frames. Nevertheless, body-centered and head-centered frames of reference appear to be important for the early and late stages of a goal-directed movement, respectively.
Work Zone Throughput Models for Southern Ontario
Keywords: Highway Work Zones, Lane Throughput, User Delay

Highway lane closures cause reductions in the traffic throughput which lead to premature queuing. To minimize user delays, contractors are required to keep highway lanes open during the peak traffic hours and work at nights. However, these limitations can reduce the quality of the work and extend project duration. Finding a right balance between the times that the lanes can be closed and the times they should be kept open can increase the efficiency of the contractors’ work. Over 100 hours of throughput data were collected in two phases from 2007 to 2010 from Southern Ontario highways. Using regression analysis, a generic and a highway specific model were developed predicting the mean throughput in approximately 50% of cases within one hundred vehicles per hour per lane of the actual mean. Also the Simplified Work Zone User Delay Analysis model, developed in Phase 1, was refined to investigate the resulting queues.
OpenCL Framework for a CPU, GPU, and FPGA Platform
Keywords: FPGA
Heterogeneous Computing
OpenCL
Reconfigurable Computing

With the availability of multi-core processors, high capacity FPGAs, and GPUs, a heterogeneous platform with tremendous raw computing capacity can be constructed consisting of any number of these computing elements. However, one of the major challenges for constructing such a platform is the lack of a standardized framework under which an application’s computational task and data can be easily and effectively managed amongst the computing elements. In this thesis work such a framework is developed based on OpenCL (Open Computing Language). An OpenCL API and run time framework, called O4F, was implemented to incorporate FPGAs in a platform with CPUs and GPUs under the OpenCL framework. O4F help explore the possibility of using OpenCL as the framework to incorporate FPGAs with CPUs and GPUs. This thesis details the findings of this first-generation implementation and provides recommendations for future work.
Fabrication of MEMS Based Air Quality Sensors
Keywords: Microfabrications, MEMS, Sensors, Automotive

This thesis deals with the fabrication of MEMS air quality sensors for automotive applications. The goal of this project is to design, fabricate and test an integrated sensor that measures three important air quality components inside the automotive cabin, which are temperature, relative humidity and carbon monoxide (CO) concentration. The sensors are fabricated on silicon substrate covered with thermal oxide and LPCVD nitride. Various deposition and etching techniques were utilized to fabricate these sensors including E-beam evaporation, thermal oxide growth, PECVD, LPCVD, RIE, KOH and HF etching. The temperature and humidity sensor use nickel as the sensitive material while the CO sensor was designed to use SnO2 although it was not fabricated to completion. A chamber was created where the temperature and humidity are controlled and the sensors were tested. Curves of sensor resistance vs. temperature and sensor resistance vs. humidity were created and the two sensor’s sensitivity was calculated.
Economies of Speed? Bike Couriers, Pace, and Economic Development in the Global City
Keywords: Economic Geography
Economic Development
Cycling Culture
Urban Metabolism
Global Cities
Skill Based Technological Change

In this thesis, I propose that bike courier delivery is not merely a convenient service for clients but an important function in the operation of successful economies. By allowing the regions to function at higher speeds, same-day courier networks seem to play an active role in generating positive economic outcomes. The availability of courier networks is found to be as uneven as economic vitality itself. Cities like New York and Toronto have large, dense courier networks, capable of delivering items within an hour while smaller cites, do not support same-day courier service at all. They do this, in part, by allowing for couriers to cope with the precariousness of their work, and in part by providing supportive sub-cultures. These findings point to the role of service workers, and wider eco-systems in fostering regional advantage.