Children with cochlear implants show deficits in identifying emotional intent of utterances without facial or body language cues. A known limitation to cochlear implants is the inability to accurately portray the fundamental frequency contour of speech which carries the majority of information needed to identify emotional intent. Without reliable access to the fundamental frequency, other methods of identifying vocal emotion, if identifiable, could be used to guide therapies for training children with cochlear implants to better identify vocal emotion. The current study analyzed recordings of adults speaking neutral sentences with a set array of emotions in a child-directed and adult-directed manner. The goal was to identify acoustic cues that contribute to emotion identification that may be enhanced in child-directed speech, but are also present in adult-directed speech. Results of this study showed that there were significant differences in the variation of the fundamental frequency, the variation of intensity, and the rate of speech among emotions and between intended audiences.

Magister Artium (Psychology) - MA(Psych) / Neuropsychiatric disorders place a great burden on the South African healthcare system. This burden is compounded by the shortage of integral human resources such as mental health care staff. Directed Masters programmes in Psychology can address this shortage as it is the practicing degree to qualify as a psychologist and subsequently register as such with the Health Professions Council of South Africa (HPCSA). A small group of students are selected into Professional Masters programmes in Psychology each year, but not all students complete their studies as some are either terminated from the programme or choose to self-terminate. There is a lack of systematic exploration of the factors contributing to non-completion due to self termination. The study therefore aimed to explore the experiences of postgraduate students that chose to self-terminate their studies in a directed Masters programme in Psychology and to identify the factors that contributed to such a decision. The study was qualitative and explorative in nature. The sample consisted of four participants who were previously enrolled for a directed Masters programmes in Psychology offered at a historically disadvantaged university in the Western Cape. The Senate Research and Senate Higher Degrees Committees of UWC (Ethics Clearance and Project Registration Number: 15/4/44) granted permission to conduct the study. Relevant ethics principles including informed consent, voluntary participation, confidentiality, and anonymity were adhered to. Data was collected through programme records and semi-structured interviews. Interviews were transcribed and analysed by two researchers using thematic analysis. Data collection and analysis occurred simultaneously until saturation was reached. Trustworthiness of the findings was achieved through continuous interrogation of multiple readings of the data, reflexivity, and external auditing. Findings revealed numerous factors that incorporate personal, programmatic and contextual considerations as motivations to self-terminate from a postgraduate programme, thus pointing to the complexity of the decision-making process within a socially embedded reality. The factors influential in self-termination prior to enrollment include the participants' interest in psychological work, their prior work experience and a need for skills capacitation which served as their motives for enrollment. Upon entry into the programme the participants experienced a disparity between their expectations and the nature and requirements of the programme, which led to a lack of satisfaction with the course. Lack of satisfaction, along with academic, physical and emotional unpreparedness, uncertainty about study choice, and perceived competence were some of the obstacles to academic integration. The dissonance they experienced were further exacerbated during enrollment by other factors such as the availability of financial support, interpersonal dynamics within the cohort group, and personal belief systems. The participants were able to find meaning in the process of self-termination as it led to a heightened pursuit of the realisation of personal goals. Participants have subsequent to their experiences in the programme been using the knowledge that they have gained in both salaried and volunteer positions, thus continuing to contribute to the field of psychology.

The purpose of this research was to establish the feasibility of delivering a 6-week long adapted Mindfulness for Academic Success (MAS) program to post-secondary students who were experiencing difficulties with their academic performance. Feasibility was established based on recruitment success (70%), program attendance (70% of participants attending at least four sessions), and homework compliance (70% homework completed). In addition, we hoped to establish the MAS program’s preliminary efficacy in improving executive and academic functioning and reducing mind wandering, inattention, symptoms of ADHD, and psychological distress. Forty participants from Carleton University were randomized to the MAS program (n = 20) or waitlist (WL) condition (n = 20). The overall dropout rate in this study was 38 %. Forty-five percent of the MAS program and 80% of the WL condition participants completed the study. MAS program completers complied with 32% of the overall homework during the five week reporting period and no student completed individually more than 57% of the assigned homework tasks. Accordingly, we did not meet the session attendance or homework completion feasibility requirements. Our preliminary efficacy results indicated significant improvements in some program outcomes in the intent-to-treat sample and results were more robust for MAS completers. Specifically executive functioning—self-management to time, self-organization, self monitoring, self-regulation of emotions, and executive function (EF) related ADHD symptoms—improved and ADHD symptoms decreased in the intent-to-treat sample and results were more robust in the completer sample. Psychological distress symptoms (depression and stress) and mind wandering decreased only in MAS program completers, but no changes were noted in students’ ability to pay attention to presented information during the mind wandering task. Academic functioning as measured by selecting main ideas, the use of study aids, and time management improved in both the intent-to-treat and completer samples. Changes in concentration and information processing were only evident for MAS program completers, however, changes were also noted in academic anxiety, motivation, and the use of test strategies, although effects were small. No changes were observed in participants’ self-restraint (EF), generalized anxiety, attitude toward school, and the use of self-testing in exam preparation. Although efficacy results suggest the MAS program may be beneficial, low program compliance and lack of change in students’ levels of mindfulness compromise the internal validity of this study and make drawing causal conclusions about the program’s efficacy difficult. Furthermore, while program attendance and homework compliance were correlated with some program outcomes, the lack of correlation between formal practices of mindfulness and program outcomes suggest that non-specific factors may have contributed to observed improvement in study outcomes.

Much confusion surrounds the term 'self-directed learning', which presently describes a process, a goal, a teaching technique, and an outcome of that teaching. As a process, the literature concentrates mainly on how individuals learn, with little reference to groups that can be as selfdirected as individuals. The purposes of this study were: (a) to reduce conceptual confusion by creating a typology distinguishing different processes of self-directed learning; (b) to explore the phenomenon of group self-directed learning; and (c) to illustrate the effect of environment on learning, and the complex learning dynamics in group settings. This project arose somewhat differently from typical doctoral research. Data from two unrelated field studies conducted for other purposes, completed before this thesis work began, each illustrated self-directed groups learning informally in the contexts of community action and innovative small workplaces. A subsequent review of the literature indicated a lack of attention to this form of group learning, and the field studies were then re-analyzed from this perspective. As a result of the literature review and data re-analysis (1) a typology emerged from the literature review that divides the process of self-directed learning into three forms, each of which is context sensitive but between which learners can continually move back and forth; (2) it appears that the term 'autodidactic' can apply to specific groups which are both self-organized and self-directed in their learning efforts; and (3) that the term 'autodidaxy' as presently defined is as conceptually confusing as the term 'self-directed learning'. This confusion is reduced by the typology proposed by this thesis. Minor findings indicate two continuing problems. The first is reluctance by some to accord non-credentialed learning the value it deserves, and the second is the difficulty often encountered in transferring knowledge from the site of learning to the site of application. This study concludes that 'informalizing' some formal curricula, and encouraging self-directed learning at all levels and in all contexts, may provide some of the tools necessary for living and learning in the twenty-first century. / Education, Faculty of / Educational Studies (EDST), Department of / Graduate

Graphs are mathematical abstractions that are useful for solving many types of problems in computer science. In this dissertation, when we talk of graphs we refer to directed graphs (digraphs), which consist of a set of nodes and a set of edges between the nodes, where each edge has a direction. Numerous implementations of graphs exist in computer science however, there is a need for more systematic and complete categorisation of implementations together with some proof of correctness. Completeness is an issue because other studies only tend to discuss the useful implementations and completely or partially ignore the rest. There is also a need for a treatment of graph representations using triples instead pairs as the base component. In this dissertation, a solution to each of these deficiencies is presented. This dissertation is a taxonomic approach towards a comprehensive treatment of digraph representations. The difficulty of comparing implementations with each other is overcome by a creating a taxonomy of digraph implementations. Taxonomising digraph representations requires a systematic analysis of the two main building blocks of digraphs implementations namely maps and sets. The analysis presented in the first part of the dissertation includes a definition of the abstract data types to represent maps and sets together with a comprehensive and systematic collection of algorithms and data-structures required for the implementations thereof. These algorithms are then written and re-written in a common notation and are examined for any essential com¬ponents, differences, variations and common features. Based on this analysis the maps and sets taxonomies are presented. After the completion of maps and sets implementation foundations the dissertation continues with the main contribution: a systematic collection and implementation of other operators used for the manipulation of the base triple components of digraphs and the derivation of the the final taxonomy of digraphs by integrating the maps and sets implementations with the operators on the sets of triples. With the digraph taxonomy we can finally see relationships between implementations and we also can easily establish their similarities and differences. Furthermore, the taxonomy is also useful for further discussions, analysis and visualisation of the complete implementation topography of digraph implementations. / Dissertation (MSc (Computer Science))--University of Pretoria, 2006. / Computer Science / unrestricted

>Magister Scientiae - MSc / Alzheimer’s Disease (AD) is a neurodegenerative disease which results from the irreversible loss of neurons in the brain. The disease is characterized by progressive cognitive impairment with recurrent short-term memory loss. AD is the leading cause of dementia and 4th leading cause of death in the elderly. Success in the treatment of AD has been limited, with drugs only treating it at a symptomatic level due to its pathology being complex and poorly understood. However, it is known that the cholinesterase and MAO-B enzymes play an important role in the disease through their association with production of amyloid plaques and oxidative stress respectively, two mechanisms associated with cell death and the symptoms seen in AD.

Thesis advisor: Abhishek Chatterjee / In the last two decades, unnatural amino acid (UAA) mutagenesis has emerged as a powerful new method to probe and engineer protein structure and function. This technology enables precise incorporation of a rapidly expanding repertoire of UAAs into predefined sites of a target protein expressed in living cells. Owing to the small footprint of these genetically encoded UAAs and the large variety of enabling functionalities they offer, this technology has tremendous potential for deciphering the delicate and complex biology of the mammalian cells. We describe the application of this technology to the modification of adeno-associated virus (AAV) for the first time, enabling the generation of vectors with precisely re-engineered cell-targeting for gene therapy. Our UAA-AAV production platform enables the incorporation of UAAs bearing bio-orthogonal reactive handles into multiple specific sites on the virus capsid and their subsequent functionalization with various labeling molecules. Incorporation of an azido-UAA enabled site-specific attachment of a cyclic-RGD peptide onto the capsid, retargeting the virus to the αv β3 integrin receptors, which are overexpressed in tumor vasculature. This work provides a general chemical approach to introduce various receptor binding agents onto the AAV capsid with site selectivity to generate optimized vectors with engineered infectivity. Next, we used our unique UAA-AAV vector as a tool for the directed evolution of more active UAA incorporation machinery in mammalian cells. It is well known that the efficiency of unnatural amino acid mutagenesis in mammalian cells is limited by the suboptimal activity of the suppressor tRNAs currently in use. The ability to improve their performance through directed evolution can address this limitation, but no suitable selection system was previously available to achieve this. We have developed a novel platform for virus-assisted directed evolution of enhanced suppressor tRNAs (VADER) in live mammalian cells. Our system applies selective pressure for tRNA activity via the nonsense suppression-dependent production of UAA-AAV, and selectivity for the specific incorporation of interest comes from a novel virus purification strategy based on the unique chemistry of the UAA. We demonstrated > 10,000-fold selectivity for active tRNAs out of mock libraries and used this system to evolve libraries generated from the commonly used archaeal pyrrolysyl suppressor tRNA, ultimately identifying a variant which is three times as active as the original tRNA. Finally, we used next-generation sequencing to analyze the fate of every library member over the course of the selection and found that our VADER selection scheme is indeed selective for the enrichment of more active tRNA variants. This work provides a general blueprint for the evolution of better orthogonal suppressor tRNAs in mammalian cells. / Thesis (PhD) — Boston College, 2019. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

Objective: To evaluate the association between the use of a 3D virtual App and academic performance among Peruvian medical students. In addition, factors associated with academic performance were also assessed. Methods: We conducted an analytical cross-sectional study in students enrolled in the Musculoskeletal System course during the first semester of 2019. Students filled out a data collection form and the "Self-directed learning readiness scale" (SDLRS) questionnaire adapted by Fisher, King, and Tangle. Linear regression models were carried out to assess the association between the appropriate use of the application and academic performance. Additionally, the factors associated with academic performance were evaluated using nested models, and beta coefficients were calculated by manual forward selection. Results: A total of 187 medical students were included. The 61% were female and the median age was 21 [20-22] years. The average grade was 13.5 +/- 2 and 21% reported an adequate use of a 3D App. No association was found between the use of the 3D App and academic performance in the adjusted model (a beta = 0.17; 95% CI: -0.45 to 0.80). We found that age (a beta = -0.22; 95% CI: -0.39 to -0.06), performing extracurricular activities (a beta = 0.75, 95% CI: 0.25 to 1.24) and having failed an anatomy/physiology course before (a beta = -2.11 to 95% CI: -2.9 to -1.8) were factors associated with academic performance. Conclusion: The adequate use of a 3D application to study the anatomy of the musculoskeletal system was not significantly associated with better academic performance. / Revisión por pares

This dissertation reports on an exploratory study of a self-directed learning framework for South African cataloguers (increasingly becoming known as metadata specialists) for facilitating their continuing education needs. The study is triggered by the 2010 report of the South African Department of Arts and Culture, which found that newly qualified information specialists cataloguers included were in practice not yet able to perform professional tasks. Continuing education is characteristic of professions and essential for keeping one's professional knowledge up to date. The study focused on the question of a framework required to support and bridge the continuing education needs of professional cataloguers in South Africa. It examines professionals' knowledge of organising information, the nature and role of selfdirected learning in their continuing education and the extent of cataloguers' commitment to selfdirected learning. These aspects are described in the research goal, namely to propose a selfdirected learning framework that cataloguers can use to facilitate their ongoing training needs. The study contains a literature review and an empirical component based on a mixed methods research approach. A survey was conducted in April-May 2015 as research method. Quantitative data was collected using a structured questionnaire (59 participants), supplemented by qualitative data from three semi-structured focus group interviews. An exploratory profile of the state of continuing education for South African cataloguers and their needs could accordingly be drawn up. Findings indicate that "self-direction" is not only related to the personality of the cataloguer. It also pertains to the process of self-directed learning and the context in which it takes place. Several theories on self-directed learning were compared to design a framework that speaks to the continuing education needs of cataloguers. Three concepts professional context, people (individuals, in collaboration with others) and learning (processes, theories and opportunities) form the background against which the framework was developed. The study concludes with recommendations about a framework for self-directed learning. It includes, inter alia, a national programme for continuing information organisation training, and the development of selfdirection in learning as a multifaceted personality trait recommended for continuing education in information organisation. Further research possibilities in relation to selfdirected learning and the self-directed learning framework are also mentioned. / Hierdie verhandeling rapporteer oor 'n verkennende studie aangaande 'n selfgerigteleerraamwerk vir Suid-Afrikaanse katalogiseerders (toenemend bekend as metadataspesialiste) vir die fasilitering van hul voortgesette opleidingsbehoeftes. Die studie is ontlok deur die 2010- verslag van die Suid-Afrikaanse Departement van Kuns en Kultuur, wat bevind het dat inligtingspesialiste insluitend katalogiseerders wat pas gekwalifiseer het, nog nie in staat is om professionele take in die praktyk uit te voer nie. Voortgesette opleiding is 'n eienskap van professies en onontbeerlik vir die byhou van professionele kennis. Die studie word gerig deur die vraag oor hoe 'n raamwerk sou lyk wat die voortgesette opleidingsbehoeftes van professionele katalogiseerders in Suid-Afrika sal ondervang en oorbrug. Die studie ondersoek professionele kennis van inligtingsorganisasie, die aard en rol van selfgerigte leer in voortgesette opleiding en tot watter mate katalogiseerders op selfgerigte leer ingestel is. Hierdie aspekte word vervat in die ondersoekdoelstelling, naamlik om 'n selfgerigteleer-raamwerk voor te stel wat benut kan word om die voortgesette leer van katalogiseerders te fasiliteer . Afgesien van literatuurontledings, sluit die studie 'n empiriese komponent in wat 'n gemengdeondersoekbenadering volg. 'n Opname in April-Mei 2015 is as navorsingsmetode aangewend. Kwantitatiewe data is versamel deur 'n gestruktureerde vraelys (59 deelnemers), aangevul deur kwalitatiewe data uit drie semigestruktureerde fokusgroeponderhoude. Daaruit kon 'n verkennende profiel van die Suid-Afrikaanse voortgesette opleidingsituasie en behoeftes vir katalogiseerders opgebou word. Bevindinge toon dat "selfgerigtheid" nie net met die persoonlikheid van die katalogiseerder verband hou nie. Dit behels ook die proses van selfgerigte leer en die konteks waarin dit plaasvind. Verskeie selfgerigteleerteorieë is in verband met mekaar gebring om 'n raamwerk te ontwerp wat die behoeftes van katalogiseerders aan voortgesette opleiding aanspreek. Drie begrippe professionele konteks, persoon (individue, in samewerking met ander) en leer (prosesse, teorieë en geleenthede) vorm die agtergrond waarteen die raamwerk ontwikkel is. Die studie word afgesluit met aanbevelings oor 'n raamwerk vir selfgerigte leer. Dit sluit onder meer in 'n nasionale program vir voortgesette inligtingsorganisasieopleiding, en 'n aanmoediging tot die ontwikkeling van selfgerigtheid in leer tydens voortgesette opleiding as 'n veelkantige persoonlikheidseienskap vir inligtingsorganisasie. Verdere navorsingsmoontlikhede met betrekking tot selfgerigte leer en die selfgerigteleer-raamwerk word genoem. / Dissertation (MIS)--University of Pretoria, 2016. / Information Science / MIS / Unrestricted

Computer systems are deeply integrated into our daily routines such as online shopping, checking emails, and posting photos on social media platforms. Unfortunately, with the wide range of functionalities and sensitive information stored in computer systems, they have become fruitful targets for attackers. Cybersecurity ventures estimate that the cost of cyber attacks will reach $10.5 trillion USD annually by 2025. Moreover, data breaches have resulted in the leakage of millions of people’s social security numbers, social media account passwords, and healthcare information. With the increasing complexity and connectivity of computer systems, the intensity and volume of cyber attacks will continue to increase. Attackers will continuously look for bugs in the systems and ways to exploit them for gaining unauthorized access or leaking sensitive information. Minimizing bugs in systems is essential to remediate security weaknesses. To this end, researchers proposed a myriad of methods to discover bugs. In the software domain, one prominent method is fuzzing, the process of repeatedly running a program under test with “random” inputs to trigger bugs. Among different variants of fuzzing, greybox fuzzing (GF) has especially seen widespread adoption thanks to its practicality and bug-finding capability. In GF, the fuzzer collects feedback from the program (e.g., code coverage) during its execution and guides the input generation based on the feedback. Due to its success in finding bugs in the software domain, GF has gained traction in the hardware domain as well. Several works adapted GF to the hardware domain by addressing the differences between hardware and software. These works demonstrated that GF can be leveraged to discover bugs in hardware designs such as processors. In this thesis, we propose three different fuzzing mechanisms, one for software and two for hardware, to expose bugs in the multiple layers of systems. Each mechanism focuses on different aspects of GF to assist the fuzzing procedure for triggering bugs in hardware and software. The first mechanism, TargetFuzz, focuses on producing an effective seed corpus when fuzzing software. The seed corpus consists of a set of inputs serving as starting points to the fuzzer. We demonstrate that carefully selecting seeds to steer GF towards potentially buggy code regions increases the bug-finding capability of GF. Compared to prior works, TargetFuzz discovered 10 additional bugs and achieved 4.03× speedup, on average, in the total elapsed time for finding bugs. The second mechanism, DirectFuzz, adapts a specific variant of GF for software fuzzing, namely directed greybox fuzzing (DGF), to the hardware domain. The main use case of DGF in software is patch testing where the goal is to steer fuzzing towards recently modified code region. Similar to software, hardware design is an incremental and continuous process. Therefore, it is important to prioritize testing of a new component in a hardware design rather than previously well-tested components. DirectFuzz takes several differences between hardware and software (such as clock sensitivity, concurrent execution of multiple code fragments, hardware-specific coverage) into account to successfully adapt DGF to the hardware domain. DirectFuzz relies on coverage feedback applicable to a wide range of hardware designs and requires limited design knowledge. While this increases its ease of adoption to many different hardware designs, its effectiveness (i.e., bug-finding success) becomes limited in certain hardware designs such as processors. Overall, compared to a state-of-the-work hardware fuzzer, DirectFuzz covers specified targets sites (e.g., modified hardware regions) 2.23× faster. Our third mechanism named ProcessorFuzz relies on novel coverage feedback tailored for processors to increase the effectiveness of fuzzing in processors. Specifically, ProcessorFuzz monitors value changes in control and status registers which form the backbone of a processor. ProcessorFuzz addresses several drawbacks of existing works in processor fuzzing. Specifically, existing works can introduce significant instrumentation overhead, result in misleading guidance, and have lack of support for widely-used hardware languages. ProcessorFuzz revealed 8 new bugs in widely-used open source processors and identified bugs 1.23× faster than a prior work.