VictorJuiz/thesis huggingface dataset:
Data-aware Computational Imaging Acceleration
Keywords: Acceleration
Computational imaging
Computer Vision
Deep Learning
Machine Learning
Neural Networks

Computational Imaging (CI) is an essential front-line building block for a wide range of applications including computer vision, advanced driver-assistance systems, medical imaging, photography and robotics. Such applications process large amounts of sensory data and need to do so either in real-time or within user-interactive setup constraints. In addition, these applications are typically run on cost- and energy-constrained devices with limited compute and memory resources. CI algorithms perform sophisticated processing of the noisy sensor output to compensate for the imperfections of the image acquisition hardware, to overcome challenging imaging conditions and to reveal new features of the captured image. This dissertation analyzes the performance of recent CI implementations on high-end commodity processors showing that practical deployment is beyond the reach of such architectures. Accordingly, the dissertation identifies unique characteristics of the data processed by these algorithms and exploits them to propose efficient data-aware CI accelerators. Specifically, this dissertation accelerates two CI implementation approaches: 1.Analytical solutions represented by Block-Matching and 3D filtering (BM3D), a state-of-the-art algorithm that is used in a wide set of core CI tasks including image denoising, sharpening, deblurring and super-resolution. We propose IDEAL, an image denoising/sharpening hardware accelerator. IDEAL incorporates Matches Reuse (MR), a novel software-hardware co-optimization that exploits typical image content to significantly reduce the computations needed without loss in output quality. IDEAL is orders of magnitude faster and more energy efficient compared to high-end CPUs and GPUs. 2.Machine learning-based implementations represented by a set of recent deep neural networks (DNNs) performing several CI tasks. We characterize strong spatiotemporal correlation between the adjacent values processed by these DNNs. Accordingly, we introduce Differential Convolution, a convolution processing technique that operates on the deltas of the values rather than on the absolute values. We propose Diffy, a novel DNN accelerator that incorporates Differential Convolution translating the characterized correlation into improved performance, reduced on- and off-chip storage and communication, and ultimately, improved energy efficiency. The proposed hardware accelerators enable practical deployment and achieve the performance needed for user-interactive, real-time and continuous vision applications. The designs are shown to outperform state-of-the-art accelerators and commodity architectures.
Ethical Leadership as a Double-edged Sword for Team Creativity: The Examination of Dual Mechanisms and a Leader’s Individualistic-collectivistic Orientation
Keywords: Collectivism
Ethical Leadership
Individualism
Norm Conformity
Psychological Safety
Team Creativity

In modern organizations, team leaders are often expected to meet two demands – creativity and ethicality. By looking at how ethical leadership relates to team creativity, the current research investigates whether the two demands can be achieved simultaneously or conflict with each other. A comprehensive review of this literature revealed equivocal past findings of the relationship between ethical leadership and creativity. Some researchers have found a positive relationship, while others have found a non-significant or even negative relationship. The central goal of this research is to provide a comprehensive understanding of the relationship between ethical leadership and team creativity by organizing the inconsistent past findings into two contradictory mechanisms: team psychological safety and team norm conformity. In addition, this research investigates when ethical leaders help their teams attend to either of the two mechanisms by examining a leader’s individualism-collectivism. A field study conducted in a chemical company where 357 employees in 105 R teams participated provided mixed support for my hypotheses. I found that despite some inconsistency, team psychological safety generally played a positive mediating role of the relationship between ethical leadership and team creativity, while team norm conformity negatively mediated the relationship. In addition, a leader’s individualism-collectivism moderated these relationships such that teams led by individualistic ethical leaders were more likely to attend to the team psychological safety mechanism, while teams led by collectivistic ethical leaders were more likely to attend to the team norm conformity mechanism.
A Meta-analysis of the Relationship between Study Abroad and Intercultural Competence
Keywords: college students
intercultural competence
meta-analysis
study abroad

A growing body of research dating back to the early 1980’s has focused on the outcomes and impacts of college and university students participating in study abroad programs. A large proportion of this research has examined how intercultural competence is enhanced for students from participating in study abroad. Intercultural competence is valued as an interpersonal skill for personal and civic responsibilities, but it is also believed to enhance employability and effectiveness in the labour market. Despite decades of research, there have been few attempts to quantify the relationship between study abroad and intercultural competence and fewer still to investigate which student, study abroad program and research design characteristics are associated with this relationship. In this dissertation, studies that included a pre-test and post-test measure of intercultural competence in a study abroad program were reviewed and coded for a series of student, study abroad and research design characteristics aligned with Engle and Engle’s study abroad program framework and Astin’s Inputs-Environments-Output model. Ultimately, 72 studies with 85 unique results were used. A random-effects meta-analysis approach was used to combine the results of all these studies into an overall effect size of g = 0.38, df(84), 95% CI (0.32, 0.45), p
Everyday Tragedies: People with Severe Traumatic Brain Injury in the Liminal Spaces of a Level I Trauma Centre
Keywords: institutional ethnography
liminality
qualitative research
rehabilitation
social relations
traumatic brain injury

Sustaining a severe traumatic brain injury (sTBI) can have a devastating and permanent impact on a person’s ability to function, on their selfhood, on their families, and on the spaces where they can exist in the world. Individuals with sTBI in Ontario are often transported to Level I Trauma Centres, as textually mediated by the provincial Life or Limb Policy, to ensure access to expert lifesaving medical care. After entering these trauma centres, transitions across the spaces of the trauma centre, from critical care to intensive care to a trauma ward, can signify recovery through decreased reliance on medical technology and medical care. Rehabilitation is required as individuals with sTBI become medically stable to ensure further improvement. This rehabilitation is needed to prepare these individuals to move to other healthcare spaces, such as inpatient rehabilitation, repatriation hospitals, or to return home. Textually mediated institutional relations through the Ministry of Health and Long-Term Care (MOHLTC), specifically the Acquired Brain Injury (ABI) Resource Rehab Tool, ignite sites of struggle in the provision of rehabilitation for individuals with sTBI. These sites of struggles reveal ruling relations that remain hidden until the institution is brought into view using an empirical method of inquiry, institutional ethnography. Specific methods in this dissertation included: participant observation, interviews, a focus group, and analysis of texts. Findings of this study suggest language in the ABI Resource Rehab Tool, specifically the discursive organizer “rehab ready” cleaves individuals with sTBI into two groups: (1) those with faster recoveries able to gain access to inpatient rehabilitation, and (2) those with slower recoveries who do not meet these restrictive guidelines and become unaccounted for in healthcare spaces, with limited options for rehabilitation. Trauma centres are medicalized spaces, whereby provincial funding is distributed on the basis of medical procedures, not rehabilitation. One notable contradiction in funding is revealed for individuals with stroke, who access beds for rehabilitation in acute care and other initiatives outlined by the provincial stroke strategy. No such provincial strategy exists for individuals with sTBI, leaving these individuals marginalized through more limited access to rehabilitation within the healthcare continuum.
States and Fates of Primitive Neural Stem Cells and Their Progeny in the Mammalian Brain
Keywords: Development
Lineage analysis
Neural stem cells
Neuroscience
Quiescence
Stem Cells

The mature brain contains an incredible number and diversity of cells that are produced and maintained by heterogeneous pools of neural stem cells. Two distinct types of neural stem cells (NSCs) in the developing and adult mouse brain include primitive (p)NSCs and definitive (d)NSCs. PNSCs form clonogenic neurospheres when grown in LIF, arise ~E5.5, and persist into the adult brain. In this and other work we show adult pNSCs are very rare and quiescent, express Oct4, and give rise to GFAP+ definitive (d)NSCs that form neurospheres in EGF and FGF2. While pNSCs can serve as a reserve pool for an ablated dNSC population in the adult brain, characterization of this activation process remains of interest, and herein I propose this occurs through transition between unique molecular states. To better understand the functions of NSCs embryonically, we performed clonal lineage tracing within neurospheres grown in either LIF or EGF/FGF2, to enrich for neural progenitor cells (NPCs) directly downstream pNSCs or dNSCs, respectively. These clonal progenitor lineage tracing data allowed us to construct a hierarchy of progenitor subtypes downstream of pNSCs and dNSCs that were validated using single cell transcriptomics. Combined, these data provide single cell resolution of NPCs downstream of rare pNSCs that would likely be missed from population level analyses in vivo.
Essays on Experimentation
Keywords: Experimentation

This thesis studies different directions of experimentation in contests (Chapter 1), experimentation in a principal-agent environment (Chapter 2), and information acquisition during the experimentation process (Chapter 3). While Chapter 1 and Chapter 3 focus on how players choose between different risky arms in different environments, Chapter 2 analyzes how to induce the agent to conduct the efficient amount of experimentation using retention policies. Chapter 1 studies firm innovation in terms of different directions of experimentation, where directions that expedite innovation success are often more costly. In a winner-takes-all contest where player action choices are public, players choose the faster but socially less efficient arms, leading to over-investment in inefficient directions of experimentation. We find that a social planner can restore full efficiency by setting a dynamic reward structure that offers a relatively small share of the prize to the winner initially, when players are still optimistic, and gradually increases the winner's prize share as beliefs drop over time in absence of a success. Finally, while information disclosure makes no difference in a two-armed bandit model winner-takes-all contest, we find that concealing player action choices in a three-armed bandit model improves efficiency. Chapter 2 studies a dynamic principal-agent problem where a principal hires an agent to experiment. We study how the principal can employ a retention policy to induce the agent to make the optimal decision in strategic experimentation, and show that, if the principal cannot commit to a retention policy, efficient experimentation cannot be achieved. However, when the principal can commit to a retention policy upfront, with probationary periods followed by infinite tenure, efficient experimentation can often be achieved. Chapter 3 builds an exponential bandit model with an experimentation arm and an information arm, where the information arm provides positive but inconclusive evidence about the state of the world, to study whether and when an agent would benefit from acquiring information. We find that a pessimistic agent often chooses the information arm as a last-ditch effort before he quits. Moreover, the presence of the information arm induces the agent to experiment more than what he would have otherwise.
Interactions between the Structural Domains of the Hedgehog-ligand Receptor, Patched-1, Mediate its Distinct Activities
Keywords: Hedgehog
Patched
Ptch1

The Hedgehog (Hh)-signalling pathway is a crucial, evolutionarily conserved signalling cascade important in animal development and de-regulated in oncogenic diseases. Central to this pathway is the principal receptor for Hh-ligands, Patched-1 (Ptch1), which in the absence of ligand, acts to repress the pathway via an indirect repression of Smoothened (Smo). Mammals also express a second Patched isoform, Ptch2, which is non-essential during development and for which the role in Hh-signalling is less characterized. Ptch1 is a 12-pass transmembrane receptor containing distinct structural modules which include two luminal “loops” responsible for binding to Hh-ligand, three large intrinsically-disordered cytoplasmic domains, and two five-pass transmembrane sterol-sensing domains (SSDs) found in a family of proteins involved with cholesterol transport and homeostasis. Despite the central role of Ptch1 in controlling the Hh-pathway, the structural aspects that determine its activities remain largely uncharacterized. The Ptch1 cytoplasmic domains, two of which (the “middle loop” (ML) and C-terminus) mediate formation of Ptch1 multimers, are unnecessary for the core functions of Ptch1. A mutant of Ptch1 lacking both of these domains is still able to repress Smo and respond to Hh-ligand. Nonetheless, these domains may have a role in regulating canonical Hh-signalling as Ptch1 missing only the ML domain acts as a constitutively active mutant which cannot be repressed by Shh-ligand. This constitutive activity is reversed upon subsequent deletion of the Ptch1 C-terminus. The two halves of Ptch1 can interact non-covalently to mediate ligand-dependent regulation of Hh-signalling. However, both Ptch1 SSDs are required for repression of Smo. Despite the high level of sequence conservation between the SSDs of Ptch1 and the cholesterol transporter NPC1, these domains are not functionally interchangeable. Finally, we describe the structural foundations for the differences in activity of Ptch1 and Ptch2. This difference in activity is not dependent on the transmembrane or luminal domains as these appear to be functionally interchangeable between Ptch1 and Ptch2. The differences in function are determined by their cytoplasmic domains, which are sufficient to allow Ptch2 to repress Smo. These observations begin to define how interactions between the structural domains of Ptch1 contribute to its functions.
Sex-Specific Behavioural Traits of the Sirtuin-3 Knockout Mouse Model
Keywords: Behaviour
Genetics
Mice
mTOR
SIRT3
Sirtuins

The NAD+-dependent mitochondrial deacetylase sirtuin-3 (SIRT3) has been recognized to regulate a number of metabolic processes in peripheral tissues, however its role in the brain remains less well investigated. The results of this thesis show that sirtuin-3 displays a unique temporal and spatial pattern of mRNA and protein expression in the developing, adult, and aged brain, that encompasses both neurons and astrocytes. These data indicate sirtuin-3 is a potentially targetable product in the brain for pharmacological interventions. SIRT3 activity does influence brain function, as behavioural alterations were observed in both male and female Sirt3-KO mice. Interestingly, only female Sirt3-KO mice were found to display hyperlocomotor and exploratory behaviour in the open field, reduced anxiety-like behaviour in plus maze and light/dark paradigms, and impaired balance on the accelerated rotarod task. These observed phenotypes were also progressive across age. In addition, both male and female Sirt3-KO mice demonstrated hyper-sensitivity to low dose amphetamine treatment compared with wild-type animals, as increased locomotor responses and lowered anxiety responses were evident in the mutants but absent in wild-type mice. These behavioural alterations correlated with an upregulation of the mTORC1 signaling pathway in the cortex in the female Sirt3-KO mice, which could underlie the observed novelty-driven hyperactive phenotype. In summary, this thesis discloses an as-yet unrecognized role for sirtuin-3 in the regulation of behavioural activity, anxiety and motor functions that is sex-dependent and influenced by both age and environment.
Measurement of the Higgs boson produced in association with a Z boson and decaying to WW∗ with a leptonic final state in pp collisions at √ s = 13 TeV with the ATLAS detector
Keywords: Associated production
ATLAS
Higgs physics
HWW
Standard Model
ZH

An analysis of the Higgs boson produced in association with a Z boson, with the Higgs decaying to WW∗ and the W and Z bosons decaying leptonically — i.e. the ZH → ZWW∗ → ```ν`ν process — is presented, using the combined 2015 and 2016 datasets from the ATLAS experiment, totalling 36.1 fb−1 of data from pp collisions at √ s = 13 TeV. Control region normalisation and a data-driven technique are employed alongside Monte Carlo estimation to predict the number of signal and background events. A cut-based approach is used to discriminate signal events from background, with cut values optimised to maximise expected significance. A statistical fit of the data, including thorough treatment of sources of systematic uncertainty, is performed, yielding a signal strength of µZH = 3.0 +1.9 −1.4 , where the Standard Model prediction is µZH = 1.
Principal Leadership for Teacher Collaborative Inquiry
Keywords: Leadership
Principals
Professional Learning for Teachers
Teacher Collaborative Inquiry
Teachers

This study investigated principal leadership for Collaborative Inquiry (CI) as a strategy for teachers’ ongoing professional learning and school improvement. A qualitative methodology was employed to generate insight into how the Ontario elementary school principals have led and supported this strategy in their school contexts. The findings show that principals’ roles in the CI process include (1) fostering the CI culture; (2) providing teachers with time and resources; (3) acting as an active co-learner, co-facilitator, and coach; (4) supporting models of shared decision-making and distributed leadership; (5) adapting CI to the school context; (6) setting the direction for the CI inquiry teams; and (7) sustaining CI. The capacity principals need to lead and support CI includes knowledge of CI and data, facilitation skills, and a growth mindset and perseverance for CI, which can be acquired in various ways including: reading CI resources, engaging in the CI process, attending professional learning sessions, accessing Ministry resources, participating in professional networks of colleagues, and listening to teachers who are involved in the CI process. The challenges and barriers principals encounter include (1) lack of time and resources for the teachers to conduct CI, (2) facilitation skills to develop a culture of inquiry and learning, (3) getting teachers to buy into the CI culture, (4) embedding a true learning CI culture at school, and (5) the stance of teacher unions which is claimed to be one source of teachers’ resistance to engagement in the CI process. To overcome these barriers and challenges, principals use some common strategies such as (1) finding time creatively for the teachers to conduct CI, (2) keeping things as focused and practically manageable as possible, (3) setting norms for building trust and ensuring a variety of opinions, (4) not using the term CI but associating CI with the existing norms and practices of collaboration and learning at school. Overall, the findings of this study corroborate and extend upon findings in the literature indicating how principals lead and support CI endeavors in schools.
Interactome Analysis Identifies Novel Targets of Phosphoinositide 3-kinase (PI3K) that Mediate Astrocyte Neuroprotection
Keywords: Astrocyte
Astrocyte Conditioned Media
Glaucoma
Neuroprotection
PI3K Interactome
ZC3H14

In a homeostatic state, astrocytes can support neuronal survival and function through a range of secreted signals that protect against neurotoxicity, oxidative stress, and apoptotic cascades. Thus, the analysis of astrocyte conditioned media (ACM) may provide valuable insight into the nature of these protective mechanisms, and how they might be promoted. Previously, we characterized a potent neuroprotective activity mediated by ACM in neurons and the retina in metabolic stress models. However, the molecular entity and mechanism underlying this activity remained unclear. Here, a chemical genetics screen revealed phosphoinositide 3-kinase (PI3K) as a central player transducing ACM-mediated neuroprotection. To identify additional proteins contributing to the protective activity, endogenous neuronal PI3K was immunoprecipitated from astrocytes exposed to ACM or control media, and MS/MS analyses were undertaken. MS data analyses pointed toward only five additional proteins that co-immunoprecipitated with PI3K and were regulated by the ACM signal. These hits included expected PI3K interactors, such as the platelet-derived growth factor receptor A (PDGFRA), and novel interactors, such as the zinc finger CCCH-type containing 14 (ZC3H14). ZC3H14 has recently emerged as an important RNA binding protein that modifies poly-adenosine tail lengths on nascent mRNA transcripts. In downstream validation studies we show that Platelet Derived Growth Factor-BB (PDGF-BB) strongly activates PI3K signaling to protect neuronal cells. Finally, PDGF-BB treatment induced recruitment of ZC3H14 to PI3K, and inhibiting this interaction eliminated ACM-mediated neuroprotection. Thus, we identified a novel ACM- and PDGF-induced neuroprotective signaling cascade mediated through PI3K that involves recruitment of ZC3H14. Enhancing this pathway may present a promising strategy to promote astrocyte-secreted neuroprotective signals.