VictorJuiz/thesis huggingface dataset:
Through the public/private lens: reconciliation, responsibility and democratization in South Africa

Democratization in the wake of state violence necessarily involves the (re)construction of a strong public/private distinction. Following Shklar's principle of "putting cruelty first," the prevention of injustice requires, at a minimum, some sort of boundary between the public and the private. An expansive understanding of the public/private distinction is proposed: procedural mechanisms of accountability are underpinned by ethical-political commitments to democratic principles and practices. A robust public/private distinction is dependent upon the integrity of its "constituent" elements: "selfhood privacy" and solidarity. In state violence, institutional abuses are supported by ethical failings on the part of "private" citizens and enabled by damage to personal capacities to resist. The erosion of social solidarity and violations of an integral sense of self corrupt or destroy the sense of injustice among victims and passive bystanders. Thus, transitional nations must attend to the institutional or political requirements of democracy and to the ethical or personal requirements of democracy. In both violence and transition, there is an interrelationship between the personal and the political, or the individual and systemic. The challenge in making a clean break with the past is finding and appropriate balance between political change and personal transformation that does not repeat or mimic the injustices of the past. The dissertation views the process of democratization in South Africa through the public/private lens. Analysis of the breakdown of the public/private distinction under apartheid reveals that egregious violence was inscribed within apartheid's structural violence. Responsibility for gross violations of human rights therefore cannot be dissociated from responsibility for human rights violations under basic apartheid law. The Truth and Reconciliation Commission (TRC) appeared well situated to establish accountability and to restore solidarity and selfhood privacy. However, narratives of forgiveness, healing and heroism glossed over the responsibility of apartheid beneficiaries and placed the burden of reconciliation upon victims. This detracted from the paramount task of affirming the personal dignity of victims and cannot be considered a clean break with the past. In post-Commission South Africa, the efficacy of new institutions and the advancement of democracy are partly dependent upon continued reconciliation and responsibility on the part of "private" citizens.
Development of a hybrid near-field scanning optical chemical probe microscope

The Near-field Scanning Optical Microscope (NSOM) is an innovative new form of microscope, which can be used to obtain both topographic images and local spectroscopic information about surfaces. In this thesis, we discuss the design and development of a hybrid instrument capable of topographic, optical and chemical probe imaging based upon a commercial Atomic Force Microscope. This thesis is divided into several sections. We first present a feasibility study, in which several possible optical configurations for the optical components instrument are reviewed. On the basis of this study, we describe in detail the implementation of two different configurations for the microscope: a dark-field illumination and far-field illumination/near-field transmission collection scheme. In the next part of the thesis, we present experiments in which we have developed a novel fibre optic probe that can be used as a combined optical, topographic and chemical force probe. A systematic approach for the development and characterisation of such probes is described including tip geometry and surface roughness, cantilever sensitivity and optical throughput. Finally, the functionality of the microscope is demonstrated by taking combined optical and topographic images of well-defined standard samples. The performance and capabilities of the final instrument are discussed and suggestions for future improvements to the setup are made.
Coherent control of biological molecules in the weak field limit

Since the birth of quantum theory, the role of quantum mechanics in biological processes has remained an open question. The wave nature of matter is now well established, and coherence effects arising from constructive and destructive interferences can be observed, in particular, in the transition state region of chemical reactions, where the operating length and timescales correspond to atomic dimensions and quantum effects become important. Using bacteriorhodopsin as a model system, this thesis provides a method to determine the relative importance of quantum coherences between reaction modes in retinal photoisomerization and thereby provide a direct test for quantum effects in a, biological function. Specifically, by carrying out coherent control in the weak field limit, the role of quantum coherences is examined in a biological system under conditions similar to those occurring naturally. By modulating the phase and amplitude profiles of the photoexcitation pulse using an acousto-optic modulator in conjunction with a feedback loop, it is possible to enhance or suppress the isomerization quantum yield, corresponding to the absolute quantity of 13-cis retinal formed upon excitation, by +/-20% in comparison to that observed using a short, transform-limited excitation pulse having the same actinic energy. Both the optimal and the corresponding anti-optimal pulse shapes consist of a series of temporal and spectral subpulses, displaying various degrees of chirp. The modulations in the optimal pulse correspond to the sim; 200 cm--1 mode involved in the torsional motion of the chromophore leading to isomerization, whereas the anti-optimal pulse presents features that are out of phase with this principal reaction mode. The high degree of control of the cis or trans branching ratio results from a combination of spectral amplitude shaping and phase-dependent coupling that resonantly drive the Raman active modes that are coupled to the isomerization reaction coordinate. The constructive and destructive interferences generated persist for timescales comparable to decoherence in the molecule, providing the possibility for coherent control. These results demonstrate that quantum coherences can play a role in biological processes, to the point that they can be manipulated.
Design of a genetic differential amplifier

The circuit was modeled using a statistical thermodynamic and stochastic approach. Simulations indicated that the circuit displayed the desired behaviour when two mutations were introduced into the promoter. One mutation added a bias to the circuit, and the other mutation made CI strictly an activator. High and low copy number variants of the amplifier plasmid were constructed and tested using several different input plasmids. A non-inverting response was observed, but an inverting response was not. A genetic analog to an electronic differential amplifier circuit was developed using components from bacteriophage lambda. A differential amplifier produces an output that is proportional to the difference between the two inputs. The activator protein CI was used as the non-inverting (positive) input. The repressor protein Cro was used as the inverting (negative) input. Both of the input proteins bound to the PRM promoter whose activity was monitored using enhanced green fluorescent protein.
Design of high accuracy power scalable MEMS sensor interface

A technique to improve power scaling efficiency of automotive MEMS pressure sensor interfaces is presented. The overall power consumption of the interface is inversely proportional to the square of the amplitude and directly proportional to the input bandwidth. Power scaling with respect to amplitude is achieved by using a novel technique of cascading gain stages through an input gain-select mux, which scales better than previous approaches. Power scaling with respect to input bandwidth of the sensor is achieved through periodic power-down of the interface. A prototype of the interface was fabricated in a 1.8V, 0.18mum CMOS process. Its power consumption scales between 4muW -- 5.33mW, while maintaining a Spurious Free Dynamic Range (SFDR) range of approximately 72 -- 92dB, a Total Harmonic Distortion (THD) range of 70 -- 90dB, and an input referred noise of 170.0nV/ Hz.
The impairing effect of a prolonged free fatty acid elevation on glucose stimulated insulin secretion

Reduced glucose-stimulated insulin secretion (GSIS) characterizes both type 1 and type 2 diabetes mellitus. An elevation in plasma free fatty acids (FFA) is characteristic of both obesity and absolute or relative insulin deficiency. Previous work by our laboratory has demonstrated that prolonged elevation of plasma FFA impairs GSIS. We hypothesized that preexisting islet inflammation/oxidative stress modulates the FFA effect on GSIS (Study#1) and that this is mediated by FFA-induced oxidative stress (Study#2). Our results indicate that the FFA-induced defect in GSIS is accentuated in pre-diabetic BB rats (model of type 1 diabetes) with insulitis (Study# 1), suggesting that islet inflammation modulates the effect of FFA. We also found that some antioxidants prevent the impairing effect of a prolonged FFA elevation on GSIS, suggesting that oxidative stress plays a role in mediating this effect (Study#2). Thus, antioxidants/anti-inflammatory agents may have therapeutic potential in type 2 diabetes and in slow-onset type 1 diabetes.
Platelet inositol trisphosphate receptor immunoreactive levels in seasonal affective disorder

Serotonergic dysfunction has been implicated in seasonal affective disorder (SAD). Changes in platelet inositol trisphosphate receptor (IP3R) levels in major depression suggest alterations in this target of the serotonin-2 receptor (5-HT2R) signaling cascade may be involved in mood disorders. To test this in SAD, IP3R levels were determined by Western blot in platelet lysates from patients with a DSM-III-R diagnosis of SAD, acquired during seasons of remission and illness, and compared with age-matched healthy subjects. IP3R2 levels (predominant subtype in platelets) were significantly higher in spring/summer versus fall/winter in SAD patients (t = 3.83, df = 8, p = 0.005) and healthy controls (t = 3.04, df = 5, p = 0.029), with no difference between diagnostic groups. There was also no relationship between IP3R2 levels and candidate gene risk variants that might affect serotonergic function. While seasonally regulated, no illness-associated disruption is evident in platelet IP3R2 levels in SAD.
Adaptive constraint aggregation for design optimization using adjoint sensitivity analysis

Constraint aggregation is the key for efficient structural optimization when using the adjoint method for sensitivity analysis. The most widely used constraint aggregation approach, the Kreisselmeier-Steinhauser function, can reduce the number of constraints and returns a conservative estimate. However, this conservative nature reduces the accuracy of the optimization results. This inaccuracy is the most prominent when constraints are active and proportional to the number of active constraints. Using an adaptive approach, this undesirable characteristic is avoided by preserving the exact feasible region. The aggregation parameter is updated according to the constraint sensitivity, and a more accurate result is obtained without additional solver evaluations. This new approach significantly improves the accuracy of the optimization when a large number of constraints are active at the optimum. This improvement is illustrated by the weight optimization of a wing box structure and demonstrated promising computational cost reduction for large-scale design optimization.

Keywords: Structural optimization
Mathematical optimization
Wireless receiver designs for asymmetric constellations

Four ASC CDMA receiver configurations composed of combinations of decorrelator/linear minimum mean square error (LMMSE) front-end filters; and Kalman filter (KF)-Maximum likelihood (ML) (KF/ML)/Wiener smoother-ML (WS/ML) joint channel estimator/data detector (CE/DD) are studied. Comparisons are made between ASCs and pilot symbols to test for similarities in their performance. The method of asymmetric signal constellations (ASC) to break isometry is studied in narrowband single-user superimposed systems and wideband code-division multiple access (CDMA) systems. Direct application of the ASC method to the superimposed framework led to a bit error floor, which motivates the proposal of three transceiver designs to solve this problem. Of all the ASC solutions, the generalized orthogonal code superimposed ASC (GOS-ASC) scheme show the best performance that matches those of a time-division multiplexed (TDM) ASC scheme.
Three essays in credit risk

This thesis consists of three essays in credit risk. The first essay examines the relationship between credit default swap (CDS) spreads and bond yields as well as the relationship between CDS spreads and credit rating announcements. We test the no-arbitrage theoretical relationship between CDS spreads and bond yields and reach conclusions on the benchmark risk-free rate used by participants in the credit derivatives market. We then carry out a series of tests to explore the extent to which credit rating announcements by Moody's are anticipated by participants in the credit default swap market. The third essay extends the 1976 Black and Cox structural model in order to value correlation-dependent credit derivatives. The proposed model assumes that the correlations between the assets of the obligors are determined by one or more common factors. We first implement a base case model where the asset correlations and recovery rates are constant. We compare our model with the widely used Gaussian copula model of survival time and test how well our model fits market prices of CDO tranches. We then consider two extensions of the base case model. One reflects empirical research showing that default correlations are positively dependent on default rates. The other reflects empirical research showing that recovery rates are negatively dependent on default rates. The second essay investigates the performance of structural models of credit risk along two dimensions. First, I analyze the models' ability to explain CDS spreads. I find that the pricing accuracy of structural models depends heavily on the market information set used in the estimation. Incorporating past time series of CDS spreads in addition to equity and balance sheet information improves the out-of-sample model pricing performance by 50%. Second, I investigate the incremental value of structural models above and beyond CDS spreads in predicting credit ratings migrations. I find evidence that three-month changes in the Distance to Default (DD) have incremental value for anticipating rating downgrades over and above changes in CDS spreads. However, this is not the case for one-month changes in DD.

Keywords: Finance
Dissertations, Academic, Canada
Effects of iron on the generation of hydrogen sulfide in a mixed culture containing sulfate-reducing bacteria (SRB) and methane-producing bacteria (MPB)

SRB and MPB can be active under similar conditions. SRB reduce sulfur oxides to sulfides that are converted into toxic H2S upon binding with protons. The objectives of this research were to determine the effects of iron(II) on the activities of SRB and MPB. Experiments were conducted using various concentrations of iron(II) up to 1,500ppm. Chemical and biological changes including pH, biomass, COD and concentrations of SO4 2−, iron(II), H2S(g), and CH4(g) were measured. Increasing the amount of iron(II) reduced the production of H 2S likely due to scavenging the produced sulfides. Apparently, iron(II) inhibited the growth of the SRB by forming iron sulfide coating around SRB. The presence of iron sulfide was observed using SEM-EDX. Iron(II) could either enhance or suppress CH4 generation depending on the change in pH or the concentration of soluble sulfides. The observed enhancement in CH 4 production was attributed to the sulfide-scavenging effect of iron.
The pedagogy of place: a naturalistic exploration of river as teacher

Rooted in the ethnographic tradition, methodologies of semi-structured interviews and participant observations are recorded and presented in narrative form. A detailed review of the relevant literature is also conducted. All available data is synthesized into eleven themes that address four central research questions. To better understand the emergent field of place-based education, this study investigates how nature, or "river," factors into teaching and learning in outdoor and experiential education. In light of growing dissonance between humans and the natural world, efforts are made to define the unique pedagogical opportunities that nature affords with properly "framed" learning experiences. The natural world is shown to contain complexities not found in indoor environments and is particularly adept as a crucible for the development of character and a sense of place. Finally, the study notes a number of conditions precedent necessitating actions by teacher and student for learning to occur.

Keywords: Nature study
Outdoor education
Experiential learning
Human beings, Effect of environment on
Composition, dissolution, and in vivo modulation of calcium phosphate nano-crystals on titania

A new method for employing Calcium Phosphate (CaP) crystals on the surface of Ti6Al4V dental implants, named discrete crystalline deposition (DCD), has been recently developed. DCD covers about 50% of the metallic substrate, hence retains the underlying microtopography of the implants while enhancing the surface complexity by means of CaP nano-features. Surface properties of the DCD-treatment, i.e. thickness and composition, were determined. In vitro and in vivo dissolution behaviour of these surfaces was also investigated. A total CaP coverage represented by single-digit micrograms of dissolved Ca from the surface was detected. The stoichiometry of CaP was consistent with the start-powder and hydroxyapatitic. In short intervals, the in vitro elution trend showed decrease of Ca release with increase in solution pH and minimal dissolution at pH 7. In vivo results demonstrated that the crystals remain intact on the surface while serving as an effective nucleation site and promoting growth of a new mineralized layer.
The role of substance P and brain neurokinin-1 receptors in relapse to drug-seeking behaviour, drug-induced locomotor activity and drug self-administration

These latter findings prompted the third series of experiments which investigated the role of NK-1 receptors in other reward-related behavioural effects of cocaine, and whether, as suggested by previous studies, NK-1 receptors may play a differential role in cocaine- and opiate-induced behaviours. Results showed that ICV administration of GR82334 attenuated morphine-, but not cocaine-induced locomotor activation, and increased heroin, but not cocaine self-administration. In contrast, [Sar9Met(O2)11]-SP decreased both cocaine and heroin self-administration. These findings suggest that while activation of NK-1 receptors may be capable of altering the reinforcing effects of both cocaine and heroin, endogenous activity at NK-1 receptors plays a specific role in opiate-induced locomotor activation and reinforcement. The primary objective of this dissertation was to investigate the role of the neuropeptide substance P (SP) and its preferred receptor, the neurokinin-1 (NK-1) receptor, in the reinstatement of cocaine-seeking behaviour. This investigation was prompted by findings demonstrating extensive interactions between SP and the midbrain dopamine (DA) system, and those suggesting that these interactions may play a role in some drug-induced behaviours. The first series of experiments extended an initial finding that injection of the SP analogue, DiMe-C7, into the ventral tegmental area (VTA) induces reinstatement of cocaine-seeking behaviour by showing that a DA D1-, but not D2-like, receptor antagonist attenuated DiMe-C7-induced reinstatement, and that intra-VTA DiMe-C7 selectively increased c-fos mRNA expression in the medial prefrontal cortex (PFC) and nucleus accumbens (NAcc). These findings suggest that the midbrain DA system, specifically D1-like receptor mechanisms, are involved in DiMe-C7-induced reinstatement, and that the medial PFC and NAcc may represent possible neuroanatomical sites mediating this effect. A second series of experiments examined the specific role of NK-1 receptors in reinstatement of cocaine-seeking behaviour, and cocaine-primed reinstatement. Results showed that ICV administration of the selective NK-1 receptor agonist, [Sar9Met(O2)11]-SP, induced reinstatement of cocaine-seeking behaviour, but that the selective NK-1 receptor antagonists, GR82334 and RP67580, had no effect on cocaine-induced reinstatement. These findings suggest that although activation of NK-1 receptors is capable of inducing reinstatement of cocaine-seeking behaviour, endogenous activity at NK-1 receptors does not play a role in cocaine-primed reinstatement.
Black students and higher education: dropping out of community college

Given the extent of this phenomenon, the drop out problem represents a major failure of the higher educational system, affecting not just the individual or the Black community in particular but the society at large and indeed the country as a whole. Dropping out represents a major loss of financial and personal investment of time and resources for Black students. Also included are recommendations for drop out prevention. The study utilizes an anti-racist education framework that focuses on the lived experiences of minorities in terms of racism and social oppression. Seventeen Black youth volunteered to participate in the study. Using semi-structured interviews, information was elicited that provides insights into how schooling and education function to disengage some students. Findings reveal that many factors impact the decision to drop out. These factors include finances, socio-economic status, parental involvement, teaching, learning, academic preparedness, and administration of education. Race although not clearly identified by most participants as a factor is still considered a serious issue worth pursuing by the researcher. The students' narratives are presented, providing valuables insights into the thinking of those who drop out. A considerable body of research has been devoted to finding out why students drop out of college and how they can be prevented from doing so. This study explores the reasons why Black students in Toronto drop out of college. The major objectives of this study were to isolate and identify factors related to drop out behavior, to examine the perception that Black students have about dropping out and to develop some preliminary ideas regarding what can be done to minimize attrition behavior, especially among Black students.

Keywords: Community college students, Ontario
Dropouts, Ontario
Students, Black, Ontario
Discrimination in education, Ontario
Machine learning algorithms for choosing compiler heuristics

During the last several decades compiler developers have invented a set of powerful heuristics to deal with the complexity of the algorithms they have to use. However, this led to a new problem of finding the best values for every heuristic. This paper describes how machine learning techniques, such as logistic regression, can be used to build a framework for the automatic tuning of compiler heuristics. In this paper we were focused on decreasing the compile time for the static commercial compiler called TPO (Toronto Portable Optimizer) while preserving the execution time. Nevertheless, our techniques can also be used for decreasing the execution time and in dynamic behavior. Our experiments showed that we can speedup the compile process by at least a factor of two with almost the same generated code quality on the SPEC2000 benchmark suite, and that our logistic classifier achieves the same prediction quality for non-SPEC benchmarks.