VictorJuiz/thesis huggingface dataset:
Thermodynamics of Impurity Removal in Solvent Refining of Silicon
Keywords: impurity
silicon
solvent refining
thermodynamics

In a new approach to metallurgical refining of silicon by solvent refining, iron has been successfully utilized as the getter element. Unlike most metallic impurities, phosphorus and boron have relatively large distribution coefficients that render them unresponsive to solidification refining processes. Consequently it is crucial to study the efficiency of phosphorus and boron removal through solvent refining with iron. This research focuses on thermodynamics of phosphorus and boron distribution between silicon crystals and the iron-silicon melt. Aiming to establish the thermodynamic fundamentals of the process, the present study was performed to investigate the distribution coefficient of phosphorus and boron between silicon and the alloy melt. Based on the values obtained for distribution coefficient of phosphorus and boron at different temperatures, impurity removal is 2-3 times more effective compared with conventional directional solidification process. The values of interaction parameter of phosphorus on iron were obtained as -5297±359 (1310 °C), -4324±292 (1260 °C) and -2893±268 (1210 °C). The values of interaction parameter of boron on iron were: -813±53 (1310 °C), -830±92 (1260 °C), -863±91 (1210 °C). Large negative values obtained for both interaction parameters, indicate strong affinity between iron and either phosphorus or boron. Self interaction parameter of phosphorus were as follows: 243±38 (1310 °C), 137±22 (1260 °C) and 18±2 (1210 °C), indicating the repulsion between phosphorus atoms. Self interaction parameter of boron were as follow: -96±12 (1310 °C), -111±28 (1260 °C) and -159±45 (1210 °C) implying an attraction between boron atoms in silicon. The distribution coefficient of phosphorus at infinite dilution were obtained as: 0.34±0.01 (1310 °C), 0.28±0.01 (1260 °C) and 0.24±0.00 (1210 °C). The same parameter for boron were: 0.49±0.01 (1310 °C), 0.41±0.03 (1260 °C) and 0.33±0.04 (1210 °C). Henrian activity coefficient of phosphorus and boron in solid silicon were also estimated.
Struggling with the State: Rights-based Governance of Reproductive Health Services in Puno, Peru
Keywords: Governance
Human Rights
Inequality
Peru
Reproductive Health
Social exclusion

This dissertation explores the complex process of how socially excluded women carry out rights-based governance in state-operated health facilities. It addresses a central tension: how can marginalized actors exercise a governance influence over institutions that have systemically excluded them? The study examines the efforts of a group of Quechua-speaking indigenous women in the southern Peruvian Andes who act as citizen monitors of their reproductive health services. In a country where profound inequalities are embedded in the health care system, the monitors (aided by a network of strategic allies) seek to combat abuse and strengthen health service provision. Key to their governance strategy is the use of a human rights-based approach to health, intended to influence monitors' power by repositioning them as rights holders. Theoretically, the dissertation draws on feminist political economy to examine the emergence of reproductive health care as a site of struggle between civil society and the state in Puno, Peru since the 1990s. It examines the monitoring initiative in Puno as an example of ongoing struggles with the state for the provision of quality reproductive health care. Methodologically, it uses institutional ethnography to link the work of citizen monitors with broader social, political and economic forces that shape their governance efforts. The study's findings suggest that human rights-based approaches can help monitors to exercise power in governance struggles. Citizen monitoring in Puno has produced some important gains, including curbing everyday injustices such as discriminatory treatment and illegal fees in health facilities. Monitors have been less effective at influencing other types of systemic problems, such as understaffing. The initiative has created opportunities for hands-on learning and the creation of new kinds of alliances. More broadly, the study suggests that rights-based governance can contribute to the democratization of reproductive health service delivery and the promotion of inclusive citizenship.
Interference Alignment in Cellular Networks: Theory, Algorithms, and System Design
Keywords: Cellular Networks
Degrees of Freedom
Interference Alignment
Interference mitigation
rank minimization

Degrees-of-freedom (DoF) is a useful yet tractable metric in characterizing the capacity of wireless multi-antenna cellular networks. DoF provides a first-order approximation (pre-log factor) to capacity and reflects capacity scaling at high signal-to-noise ratios. Interference alignment is a concept that is used to design linear beamformers that achieve the optimal DoF of multi-antenna wireless networks. This thesis focuses on the role of interference alignment in establishing the maximal DoF of multi-antenna cellular networks and its relevance in practical cellular network optimization. The primary focus is on studying the symmetric DoF of cellular networks that consist of G mutually interfering cells with K users/cell, having N antennas at each base station and M antennas at each user. The first part of this thesis investigates the achievable DoF using two different strategies for interference alignment. The first is an asymptotic alignment scheme that is typically used in single-antenna networks and relies on symbol extensions in time, and the second is a linear beamforming strategy that exploits overlap of transmission subspaces in multi-antenna receivers. It is shown that there are distinct regimes of G, K, M, and N, where one technique outperforms the other. Using a set of outer bounds on the sum-DoF, conditions for optimality of the DoF achieved using the two techniques is established. Studying the optimal DoF highlights the importance of developing algorithmic techniques for interference alignment. The second part of this thesis focuses on the design of linear beamformers for interference alignment. Conditions for interference alignment are formulated as a rank minimization problem and insights from compressive sensing are used to develop algorithms that can efficiently solve this problem. The proposed algorithms are shown to be more effective in designing aligned beamformers for interference alignment than other existing algorithms. The final part of this thesis explores the value of interference alignment in practical cellular network optimization. Using a two-stage optimization framework, it is established that interference alignment is valuable in dense cellular networks where interference alignment provides an altered interference landscape that subsequent network utility maximization algorithms can take advantage of, but is otherwise difficult to reach.
Enhancing Rigour in Orthopaedic Manual Physical Therapy Certification: Development of an Assessment Rubric for a Test of Clinical Reasoning
Keywords: Assessment
Certification
Clinical Reasoning
Manual Therapy
Physical Therapy
Validity

Background: Assessment of competence is an important part of post-graduate certification in the health professions. These assessments result in judgments about how candidates would perform in real practice; thus, certification processes can have wide reaching implications for the candidate, the certifying institutions, and the public. In the field of Orthopaedic manual physical therapy (OMPT), post-graduate certification entails the assessment of a range of competencies including clinical reasoning. OMPT is an internationally recognized subspecialty within physiotherapy, and certification in this domain occurs worldwide. Yet, there is currently little documented evidence supporting OMPT certification processes. This is an issue because the validity of these processes may be questionable and vulnerable to scrutiny. Purpose: To address this research gap, this dissertation aimed to enhance the rigour of OMPT certification by developing and testing a new assessment rubric to standardize the appraisal of written responses to a short-answer test of clinical reasoning. Methods: To accomplish this aim, a modified Delphi method was used to determine the clinical reasoning assessment criteria important for OMPT certification. An assessment rubric called the Case History Assessment Tool (CHAT) was then constructed based on these assessment criteria for the Canadian short-answer test of clinical reasoning. Using validity theory as a framework, a second and third study was conducted to generate validity evidence for the content, response process and internal structure associated with the CHAT. Results: This dissertation yielded 53 assessment criteria which were strongly endorsed by an international panel of OMPT experts. These criteria were subsequently applied to develop a standardized assessment rubric for the Canadian short-answer test of clinical reasoning. Validity evidence was generated from three different sources that support the content, response process and internal structure of the CHAT. Conclusions: The assessment criteria identified through this dissertation will be relevant to other OMPT training programs insofar as institution-specific testing occurs prior to their use. Validity evidence was generated to support the scores derived from the CHAT within the Canadian OMPT certification context. Further validity evidence is needed from other sources of validity within this context. Finally, the contextual factors of clinical reasoning will need to be considered in the development and assessment of clinical reasoning in post-graduate certification.
Group Dynamics in Drosophila melanogaster
Keywords: Social Interaction Networks

The study of the social environment of Drosophila melanogaster has revealed social effects on the regulation of genes, physiology, and behaviour. More recent studies have also uncovered complex, group-level phenotypes that defy explanation through a dyadic framework of interactions. Yet studies characterizing the group's internal dynamics - organisation and synchronisation - are sorely lacking. I address this by implementing a new methodological paradigm to study Drosophila melanogaster groups. My initial contribution establishes a robust new phenotype - Social Interaction Networks - that quantifies the structure of a given set of interactions within a group. Prior to this, Drosophila were sometimes thought of as solitary agents which, lacking a suitable courtship or aggressive target, would aimlessly move about randomly encountering other individuals. I show that these `random encounters' in an arena are in fact non-random, and that their organisational structure varies among strains and sex. Secondly, I use a novel rule-set to automatically determine and characterize these non-random `encounters', and to show their dependence on chemosensory feedback. By determining and standardizing the ways in which flies interact, I show an increased power in the ability to explore the Social Interaction Networks of flies. Finally, I measure the effect that group size has on the Social Interaction Networks of Drosophila, and examine the flies' ability to compensate for density effects by adjusting their interactive behaviours within the group. I also test the effect that group size has on group identity, by examining in tandem both behaviour and genetic regulation, to reveal a synchronising effect in a group of freely interacting flies. I find a complex sex-dependent relationship between group size and synchrony, although both males and females benefit from larger group sizes. This thesis therefore reports novel methods and findings that take us closer to understanding the complex social life that patterns itself inside Drosophila melanogaster groups.
The Life of Marcel Tournier and a Guide to the Performance Practices of his Music
Keywords: Authenticity
Harp
Music
Performance
Performer
Tournier

The primary goal of this dissertation is to expand the body of knowledge related to the life and compositional developments of harpist-composer, Marcel Tournier, thereby providing insight into the performance practices of his music. Through archival research in France, and through interviews conducted with Tournier family members, the biography on Marcel Tournier has been expanded. In order to establish the performance practices of Tournier's music, interviews were conducted with three of his students: Elisabeth Fontan-Binoche, Huguette Geliot, and Gérard Devos. The results of these interviews provide insights into the compositional style and interpretive elements of Tournier's music. The second goal of this dissertation is to address the performer's role within the discussion of authenticity in music, encouraging the performer to make informed and thoughtful performance choices in the harp repertoire of Marcel Tournier. Issues relating to the interpretation of the text (score), and composer's intentions are also explored. Through a detailed interpretive analysis of Tournier's Vers la source dans le bois (1921), a model emerges which allows for understanding of the text and the composer's intention, and situates the performer's role in the interpretation of the music. This model may be adapted and applied to significant works of the harp repertoire.
Perinuclear Chromosome Tethers and RNA-DNA Hybrid Suppressors Maintain Genome Stability and Cellular Lifespan
Keywords: DNA-RNA Hybrid
Genome stability
ribosomal DNA
RNA regulation
Spatial genome organization
telomeres

Aging and related pathobiological conditions often involve genomic changes including alterations of repetitive DNA regions typically assembled into heterochromatin or silent chromatin structures. For example, telomeres and ribosomal DNA (rDNA) repeats are linked to aging in various organisms including yeast and humans. Our work has uncovered functions for the Cohibin protein complex in maintaining replicative lifespan of the budding yeast Saccharomyces cerevisiae through roles in tethering telomeres and rDNA repeats to the nuclear envelope. In addition, we found that the telomere-associated protein Rif1 sets the ideal lifespan-sustaining distribution of the conserved histone deacetylase Sir2 between telomeres and rDNA repeats. Moreover, we discovered distinct roles for the Cohibin-interacting protein Pbp1 in rDNA and lifespan maintenance via binding of intergenic non-coding RNA transcripts and subsequent suppression of RNA-DNA hybrids. We also uncover a role for the lifespan-promoting intervention known as caloric restriction in the engagement of magnesium-dependent hybrid suppressors to abolish hybrid accumulation associated with Pbp1 loss. In all, we discovered that perinuclear chromosome tethering and RNA-DNA hybrid suppression help maintain chromosome stability and cellular lifespan.
Beating Quantum Hackers
Keywords: Measurement device independent QKD
Quantum cryptography
Quantum hacking
Quantum key distribution
Quantum random number generator

Cryptography plays a key role in today's digital society. The most widely used encryption method is the public-key algorithm, but its security relies on unproven computational assumptions. In contrast, quantum key distribution (QKD) is an unbreakable encryption algorithm. QKD has been proven to provide information-theoretic security rigorously based on the laws of physics. Despite the beauty of QKD theory, in practice, QKD still suffers from practical side-channel attacks, due to the imperfections of real-life implementations. Such discrepancy between the theory and the practice is fatal to the security of a QKD system. This thesis addresses a number of the discrepancies in a standard QKD implementation, and it offers efficient countermeasures to resolve these discrepancies. A novel protocol -- measurement-device-independent (MDI) QKD - was proposed to remove all detector side-channel attacks. To apply MDI-QKD in real life, I have proposed practical protocols, conducted the first rigorous finite-key security proof, designed methodologies to optimize parameters, and demonstrated MDI-QKD experimentally. These results allow MDI-QKD mature enough to be implemented in real-life. Based on the framework of MDI-QKD, the only security issue left is the source. To solve the loophole due to the imperfect encoder, I have experimentally implemented a recent protocol, which enables QKD loss-tolerant to source flaws. This experiment for the first time shows secure QKD with imperfect state preparations at long distances. Another vulnerable part in the source is the ability to generate true randomness. I have developed a compact and cost-effective quantum random number generator (QRNG) prototype, which has a real-time generation rate of 1 Gbit/s with excellent stability. The simplicity and speed of my prototype prove the feasibility of a robust, low-cost, and fast QRNG. In summary, MDI-QKD enables new scientific developments in the field of quantum cryptography. This thesis solves the major practical issues in the implementation of MDI-QKD. The combination of MDI-QKD, imperfect sources, and QRNG consists of the foundation of a future practical side-channel-free QKD protocol. The success of this protocol can substitute current classical cryptosystems by offering people an unconditionally secure infrastructure, which will be the ultimate dream for researchers in secure communication.
Sounding the Inner Voice: Emotion and Vocal Emulation in Trumpet Performance and Pedagogy
Keywords: Emotion
Trumpet
Vocal Approach
Vocal Emulation

Sounding the Inner Voice: Emotion and Vocal Emulation in Trumpet Performance and Pedagogy Geoffrey Tiller Doctor of Musical Arts Faculty of Music University of Toronto 2015 Abstract This dissertation examines the aesthetics of trumpet performance with a focus on the relationship between a vocal approach and expressiveness in trumpet playing. It aims to improve current trumpet pedagogy by presenting different strategies for developing a theory of a vocal approach. Many of the concepts and anecdotes used in respected pedagogical publications and by trumpet teachers themselves are heavily influenced by the premise that emulating the voice is a desired outcome for the serious trumpet performer. Despite the abundance of references to the importance of playing trumpet with a vocal approach, there has been little formal inquiry into this subject and there is a need for more informed teaching strategies aimed at clarifying the concepts of vocal emulation. The study begins with an examination of vocal performance and pedagogy in order to provide an understanding of how emulating the voice came to be so central to contemporary notions of trumpet performance aesthetics in Western concert music. Chapter Two explores how emotion has been theorized in Western art music and the role that the human voice is thought to play in conveying such emotion. The final chapters develop a pedagogy of voice-like expression by integrating exercises based on Constantin Stanislavski's acting method, narrative analysis, and applied vocal practices to trumpet performance to strengthen the links between voice, emotion, and expressive musical communication.
Building Peaceful Secondary School Climates: A Comparison of Anti-violence, Equity, Engagement and Community-Building Practices
Keywords: Educational Administration Policy
Relationship Building
School Climate
Social Psychology
Sociology of Education
Violence Bullying PreventionE Intervention

Regularized daily practices in schools that exacerbate competition and exclusion in social relationships create environments in which conflicts are more likely to escalate into severe violence (Aronson 2000). School practices that rely on harsh punishment to prevent violence are often ineffective because punishment tends to fracture or impede the development of healthy relationships (Gladden 2002). This qualitative case study research examines various practices employed in three Ontario public high schools, linked to reducing the incidence of violence. Based on semi-structured interviews with school administrators, staff members and students, contextualized in relation to analysis of publicly-available documents, I describe, compare and analyze anti-violence, relationship-building, engagement and community-building practices and their perceived effectiveness in building peaceful school climates. Results show that proactive opportunities for students to develop a strong sense of attachment to their school, practice cooperation, and develop positive student-student and adult-student relationships seemed to be associated with building and/or sustaining peaceful school climates. School practices that placed students in cooperative horizontal relationship structures with peers, and communicative vertical relationship structures with adults, seemed to encourage peaceful interactions and support the development of social capital (relationship resources) for some student participants. In contrast, punitive practices to conflict and violence, such as suspensions, showed no evidence of building peace. Opportunities to engage in restorative peacemaking dialogue practices, although minimally used, seemed promising to resolve broken relationships in each school. This research supports the theory that reducing competition and exclusion and cultivating cooperative social relationships are promising practices that can reduce the risks of physical violence, bullying and other forms of aggression in schools. Unlike correlative survey research that may link incidence of aggression to individual student characteristics, this research points to proactive patterns of policy implementation and practice by school-based staff--based on inclusive interaction instead of harsh and exclusionary punishment--that may contribute to the achievement of sustainably peaceful climates.