VictorJuiz/thesis huggingface dataset:
Analysis of beta-amyloid aggregation and amyloid precursor protein dimerization

Alzheimer's Disease (AD) is a neuropathological disorder characterized by the progressive deposition of insoluble amyloid plaques and vascular deposits consisting primarily of 4.5 kDa amyloid beta peptides (Abeta). There is increasing evidence that the deposition of Abeta fibrils in the brain, an invariable feature of AD, and/or prefibrillar aggregates likely cause neurodegeneration in AD. While Abeta fibrils were a previous research focus, recent experiments implicate prefibrillar aggregates as the toxic species. The identification and characterization of prefibrillar aggregates is of great importance to understanding AD and the development of therapeutic strategies. Biophysical and spectroscopic techniques were used to examine the effects of electrostatic interactions on Abeta oligomerization. Experimental work demonstrated that, while salt bridges likely provide stability to preformed Abeta aggregates, these interactions are not essential for the early stages of aggregation. Abeta oligomerization is driven by the formation of pH-independent interactions and is impeded by electrostatic repulsion at pH values away from the isoelectric point. Diffuse plaques, containing only the 42-residue form of Abeta, are unstructured and non-toxic; they appear before toxic senile plaques containing both 40 and 42-residue forms. Through incubation, Abeta40 and Abeta42 were shown to co-incorporate into unstructured aggregates early during fibrillogenesis later leading to tightly packed aggregates with secondary structure. Previously, the stage at which the Abeta variants co-incorporated during the fibrillogenic process was unknown. After observing that the amyloid precursor protein transmembrane (APP-TM) domain contains two known dimerization motifs (GXXXG/A), oligomerization of the APP-TM domain was examined. A model system was developed to investigate the effects of familial AD mutations on the dimerization propensity of APP-TM domains. This work culminated in the first experimentally supported mechanism to explain how genetic mutations within the APP gene lead to the observed phenotype and predisposition to AD. Further experimentation led to the discovery of non-denaturing detergents that stabilize suspected on-pathway spherical Abeta aggregates. These detergent-stabilized Abeta oligomers share many of the structural features and biological activities of both membrane bound Abeta and spherical oligomers of Abeta formed in solution. Thus, these stabilizing detergents may prove useful in high-resolution structural analysis of spherical oligomers.
Vascular smooth muscle cell activity and response to arterial injury in heparan sulfate-deficient perlecan mice: Identifying a role for perlecan in smooth muscle cell regulation

Percutaneous coronary interventions are limited by restenosis, a process that involves smooth muscle cell (SMC) proliferation and migration. Perlecan, a heparan-sulfate proteoglycan present in the vessel wall has been shown to inhibit SMC activity in vitro and decrease intimal hyperplasia in animal models of arterial injury. The function of heparan sulfate (HS) on perlecan is poorly understood. We found that SMC expressing HS-deficient perlecan exhibit increased proliferation, migration and adhesion than SMC expressing intact perlecan. Additionally, following arterial injury, mice expressing HS-deficient perlecan undergo greater medial thickening and restenosis. Moreover, induction of perlecan results in increased inhibition of SMC activity in vitro, suggesting perlecan's role in SMC regulation is an inhibitory one, which may be a possible therapeutic target for the prevention of restenosis.
Two experienced teachers' perceptions of the International Baccalaureate mathematics program

This study sought to understand the perceptions of two experienced teachers to the International Baccalaureate mathematics program. Components of the IB diploma program were identified which attract these two teachers and influence some part of their teaching cycle in their classroom. This information was obtained through a qualitative case study, in which data was collected by classroom observation, questionnaires, informal discussions and audiotaped interviews. Both teachers identified the IB diploma philosophy, the mathematics curriculum, the IB external assessment, and working with IB colleagues as the most attractive components of the IB program. The IB mathematics program influenced one teacher the most by strengthening her teacher efficacy, whereas the second teacher was most interested in the affect of the IB program on student outcomes in his classroom. Teacher knowledge and beliefs, teaching techniques and assessment strategies were affected to a lesser extent and by varying degrees between the two teachers.

Keywords: International baccalaureate
Mathematics, Study and teaching (Secondary)
Mathematics teachers, Attitudes
High school teachers, Attitudes
Design methodology for millimeter-wave low-noise amplifiers

This thesis describes a systematic design methodology for millimeter-wave, low noise amplifiers (LNAs). It focuses on the inductively--leaded SiGe HBT cascodc LNA topology. Three LNAs operating at 50 and 65 GHz are fabricated in 0.18mum SiGe BiCMOS technology to validate the proposed methodology. The measured LNA performance agrees well With simulations and is close to the theoretical limit in the given technology. Several of the LNA low-noise design techniques are applied to the design of a 65-GHz receiver integrating an LNA, a down-conversion mixer, a full-rate VCO, and an IF amplifier. The fabricated receiver has a gain of 24 dB and a noise figure of 12 dB. Using compact on-chip inductors, the IC occupies an area of 0.6 mm2, several times smaller than similar published receivers. To the best of the author's knowledge, it is the first millimeter-wave silicon receiver to integrate the VCO on-chip.
Stuctural insights into rabbit N-acetylglucosaminyltransferase I donor specificity, acceptor binding and catalysis

N-acetylglucosaminyltransferase I (GnT I) is a carbohydrate processing enzyme in the Golgi that initiates the conversion of high-mannose oligosaccharides to complex and hybrid structures in the biosynthesis of N-linked glycans in the secretory pathway. Building on the previously determined x-ray crystal structure of the nucleotide-bound complex of GnT I in the presence of its native substrate, we obtained a series of highresolution nucleotide-sugar analogue complexes that provide structural insight into nucleotide-sugar recognition and underscore the importance of the sugar C2 position in catalysis. In particular, our crystallographic studies of GnT I provide evidence for the importance of the GlcNAc moiety and its N-acetyl group in substrate binding, as well as the role played by a flexible loop in substrate binding and product release. Moreover, by modeling the oligosaccharide substrate in the active site, we were able to suggest a rationalization for the main determinants of GnT I oligosaccharide specificity.
Hybrid polymer-semiconductor materials optically active in Vis-NIR region

Composites consisting of polymer and semiconductor nanoparticles were prepared by electrodeposition technique. Electrodeposition parameters including voltage, deposition time were optimized to obtain composite films with good performance. Optically active in near-IR region PbS nanocrystals were synthesized in water solutions. Short carbon chain thiols were used as capping ligands. The evolution of the nanocrystals was studied and the stability of NCs was improved by using mixture of thioglycerol-dithioglycerol as capping ligands. Optical properties of the nanocrystals in solutions and in polymer-semiconductor composites indicated good stability and high quantum efficiency with a quantum yield of the nanocrystals as high as 17%. Good stability of the nanocrystals was confirmed in several biological systems. The light-emitting devices based on conducting polymer-nanocrystal composite structures were prepared. For the applied voltage of 4–5V efficient infrared electroluminescence was observed.
Multicultural democracy in the city: Explaining municipal responsiveness to immigrants and ethno-cultural minorities

This study explores why and how local leaders in Canada's immigrant magnet city-regions adapt municipal governance structures in response to increasing levels of ethno-cultural diversity. It compares the responsiveness of eight highly diverse urban and suburban municipalities to immigrants and ethno-cultural minorities including: Toronto, Mississauga, Brampton and Markham in the Greater Toronto Area and Vancouver, Richmond, Surrey and Coquitlam in the Greater Vancouver Regional District. Given the novelty of this empirical terrain, the study begins by documenting and evaluating municipal responses and creates a typology of municipal responsiveness to immigrants and ethno-cultural minorities. Then, the dissertation explains why Canadian municipalities vary in their responsiveness to immigrants and ethno-cultural minorities by engaging with the dominant theoretical paradigm of the urban politics literature - urban regime theory. Through detailed case studies, the thesis documents the development of lasting coalitions---urban regimes---in several municipalities. In this way, it demonstrates how some municipalities have managed to develop policy capacity in the settlement and multiculturalism policy fields---despite their tight fiscal constraints---by pooling private sector and public sector resources. The inquiry also looks at factors that shape the way in which urban regimes develop. It develops two categories of ethnic configurations---"biracial" and "multiracial"--And explores how and why these configurations affect urban regime development. The study concludes that, all other things being equal, multiracial municipalities are less responsive to their immigrant populations than biracial municipalities. The analysis also explores the role of the intergovernmental context in municipal responsiveness to immigrants and ethno-cultural minorities. It finds that the province matters a great deal to municipal governance in Canada but in more complex ways than the constitutional relationship between provinces and municipalities would suggest. What is clear at the conclusion of this dissertation is that municipal governments are much more than simple "creatures of provinces". They are important democratic governments that are at the vanguard of social change.
Incremental redundancy via check splitting

A new method of creating rateless codes for noisy channels is presented. Unlike puncturing, where every punctured variable disables several checks, or extending, which creates many cycles in the code graph or creates parity checks with insufficient weight, the proposed method uses check splitting to lower the rate of the code. Check splitting operates by replacing a row r of maximum weight in the parity check matrix with two new rows s1 and s2, of approximately equal weight and with s1 ⊕ s 2 = r. This causes the check-node degree-distribution to remain fairly concentrated and prevents cycles from forming as the rate decreases. This scheme performs closer to capacity than Raptor codes, it can use a linear-time-encodable code such as a repeat-accumulate code, and it has nearly constant decoding complexity per information bit per iteration, independent of the effective code rate.
An evalution of the ASTM standard method for measuring chemical shrinkage of hydraulic cementitious pastes

Hydration is the chemical reaction of cement and water in concrete which produces hydrated compounds such as C-S-H and Ca (OH) 2. These products have a smaller specific volume than the constituents which results in chemical shrinkage. At low water cement ratios external water will not be able to replace the lost volume which results in autogenous shrinkage. Even when drying is prevented, internal shrinkage can occur. In some cases, this can lead to internal micro-cracking. To measure chemical shrinkage the cement paste has to be water saturated to replace the volume decrease due to hydration. Chemical shrinkage can be measured using dilatometry which is based on the direct measurement of the length or volume change of water and is considered a quick test for rates of hydration. The National Institute of Standards and Technology (NIST) has made some efforts to develop a standard test method to evaluate the rate and extent of chemical shrinkage. ASTM C1608-05 was developed and will be evaluated, improvements implemented and sensitivity as well as ruggedness tests performed. Tests were also run at low water cement ratios to look at the effects of chemical shrinkage.
Contesting social exclusion: an interrogation of its self-imposed expressions

The first stage of analysis demonstrates the inherent contradictions and uncertainties arising through the application of the most popular version of social exclusion as an individual kind. Repositioning this categorical idea and its assumptions as integral to the processes of social exclusion itself, the following chapter provides an analysis of the four forms of social exclusion---economic, spatial, socio-political, and subjective---as denied access to legitimate means of appropriating various species of capital from dominated positions in the market-state social field . In the third findings chapter, the specific role of the state in the dynamic processes of social exclusion is evidenced as the meaning, vilification, and racialization of difference, and ultimately the production of the classifying habitus. Finally, through an in depth exploration of conflicting meanings of work in competing social fields, the practices that appear to be expressions of self-imposed social exclusion are reinterpreted as the necessary means for the appropriation of capital---for survival---in the places in-between the various social fields in which many people inevitably participate. Popular articulations of social inclusion as an indisputable social value and inspired direction for social policy are contingent on its undesirable counterpart, and can be realized only through imposing a "vision of divisions" constituted by oppositional social groups or kinds. This study begins from the premise that in order to move beyond the 'commonsense' idea of social inclusion as a conserving system of social classification, application of the term must remain attached to its economic, political and social contexts, and a reconfigured notion of social exclusion as both kind-and-process is applied through Pierre Bourdieu's anti-dualist, reflexive approach to social research. This project is an exploration of the idea and social realities of social exclusion, particularly its self-imposed expressions, as experienced by various ethno-religious communities of Low German Mennonite migrant workers in southern Ontario. Readily visible among many in this population are the external markers of poverty and social exclusion. Their tenacious commitment to a distinct way of life and a predisposition for endless migration suggests that their social exclusion is, on the surface, collectively self-imposed and furthermore, voluntary.
AspeCt-oriented C (ACC)

Aspect-oriented software development (AOSD) is an emerging software engineering methodology helping modularize crosscutting concerns which are difficult to be cleanly modularized by traditional programming models, like object-oriented (OO) or procedural programming. Its programming model is called aspect-oriented programming (AOP). Though AOSD has been shown to improve the modularity of software systems when combined with 00 languages, like Java or C++, it is still questionable whether it could help C create software systems with high modularity. One reason for relatively slow adoption of AOP in C is lacking tool support. Without stable and powerful tools, researchers could not incorporate AOP into C. In order to provide a good tool, ASPECT- ORIENTED C (ACC) was developed. It implements most well-known AOP features and introduces some new features. This thesis describes the A SPECT-ORIENTED C language specification, the ACC compiler, and several case studies on industry-scale C projects using ACC.
Calcium-stimulated adenylyl cyclase 1 regulates synaptic scaling in forebrain cortical neurons

Homeostatic plasticity is important to stabilize the activity level of neuronal circuits. Molecular mechanisms underlying neuronal homeostatic plasticity in response to activity deprivation are not completely understood. This study found Chat prolonged AMPA receptor blockade by CNQX resulted in larger, faster mEPSC events with enhanced frequency. Furthermore, GluR1 protein level was also increased in cultured forebrain cortical neurons. Blockade of L-type Ca2+ channels produced similar effects as AMPA receptor blockade. Genetic deletion of AC1 but not AC8 KO, a key neuronal calcium-stimulated adenylyl cyclase, significantly reduced CNQX-induced GluR1 changes. The results indicate the synthesis and possible insertion of homomeric GluR1 receptors into synapses due to synaptic inactivity in the cortex. AC1 plays a subtype selective role in this process by coupling signals from L-type Ca2+ channels to downstream signaling pathways.
PTEN suppression-mediated neuroprotection in ischemic neuronal injury

The tumor suppressor PTEN is a lipid and protein phosphatase that has been shown to play a key role in regulating diverse molecular events of mammalian cells. In the context of ischemic damage, there is evidence that suppressing PTEN activity brings about neuroprotective effects, yet the underlying mechanisms of this protection remains unclear. Recently, a novel PTEN inhibitor, bpV(pic), has been shown to preferentially inhibit PTEN at nanomolar concentrations in non-neuronal cells. As an important first step for further elucidation of PTEN signaling pathways in the CNS, I hypothesized that BpV(pic) treatment produces PTEN suppression-mediated neuroprotection in rat cortical cells. My research showed that treatment with 200 nM bpV(pic) (1) enhanced the phosphorylation of Akt in vitro and in vivo, (2) did not inhibit protein tyrosine phosphatases at nanomolar concentrations, (3) protected against oxygen-glucose deprivation-induced injury. Additionally, preliminary data showed that BpV(pic) treatment reduced the surface expression of GABA AR-gamma2 subunits.
Automata-based scheduling and control of flexible manufacturing workcells

Scheduling and control of Flexible Manufacturing Cells (FMCs) have been of continuing theoretical and practical importance to the operational-research and automatic-control communities, respectively. Petri Nets (PNs) and controlled-automata have been two commonly used techniques for FMC modeling and supervisory controller synthesis. However, although the literature contains a large number of PN-based scheduling methods, there have been no attempts to utilize automata theory for similar endeavors. This thesis is one of the first reported research efforts for using automata theory for simultaneous scheduling and control of FMCs. In order to verify the effectiveness of the proposed methodologies, a MS-Windows based software was developed to simulate the implementation of the methodologies for different FMC configurations. Numerous simulations clearly demonstrated that the proposed methodologies can control FMCs and improve their performances simultaneously. An automata-based supervisory controller ensures that the plant under supervision will behave deadlock-free (according to given specifications). However, it lacks decision-making ability. The overall research objective of this thesis, thus, is to develop automata-based methodology for synthesizing FMC controllers capable of monitoring, controlling, and making scheduling decisions such that they could control the flow of parts within the workcell, satisfy the deadlock-free requirements, and improve the FMC performance simultaneously. As proposed in this thesis, first, time-augmented automata are used for system modeling purposes. Supervisory-control theory is, then, used as the supervisor-synthesis method. The constructed supervisor, representing deadlock-free FMC behavior, is utilized to search for the optimized workcell behavior. For the above-mentioned three problems an A* based search methodology, a Non Linear Programming (NLP) modeling method, and an on-line beam-search based methodology are utilized, respectively. Three formal methodologies are proposed to solve three basic control and scheduling problems, respectively. The first problem deals with off-line scheduling for batch production. The second problem deals with continuous production, where parts, one by one, are continuously introduced into the workcell. It is assumed that only the probability of arrival of the incoming part is known in advance. The third problem deals with random-arrival production, where the controller has no a priori information about the arrival of parts and has to evaluate the state of the workcell and determine possible available alternative decisions in an on-line manner.
Morphosyntactic idiosyncrasy and lexical specification

This thesis investigates the lexicon as a linguistic subcomponent interacting directly with the computational system of language. I propose that morpho syntactically idiosyncratic patterns result from functional marking or lexical specification on the lexical entry. I argue that this specification (1) is highly structured, (2) when applied to verbs, affects their direct object-licensing properties, and (3) interacts with the verb's lexical constant (root) to produce the observed argument-taking properties of the verb. The data examined include various less-than-productive constructions with the clitic sieı (SE) in Polish. These SE uses include verbs labeled (1) inherently reflexive (e.g. smiac sieı 'to laugh', bac sieı to fear'), (2) idiomatic reflexive (e.g. object impersonal SE constructions), (3) affective (e.g. wrocic sieı 'to come back', with the action focused on subject and more telic than the non-SE alternant) and (4) "up-to-completion" constructions where the combination of perfective verb prefixation and the clitic indicates a completed and lexically nuanced action. Moreover, comparisons are made to quantized structures in Spanish (e.g. Juan se comio una manzana 'John ate an apple up', where the clitic unambiguously indicates total consumption of the apple).I propose that these verbs and constructions involve the lexical specification of functional material projecting as Transitivity and Aspect. The different interpretations of SE arise as a result of the interaction of the clitic's underspecified phiv;-features with variably realized Transitivity and Aspect projections, and different referential relations in the constructions. I extend the functional architecture adopted for the proposal to productive constructions with SE in Polish. I also explore the lexical specification of other functional layers such as Tense. The thesis thus addresses the question of parameters and limits of lexical specification, both desirable within a Minimalist program of linguistic research.
Restructuring pay equity in the era of the new economy

The concept of ‘pay equity’ reflects the idea of ‘equal wage for work of equal value’ and it was developed in response to the phenomenon of the gender wage gap and the concentration of women in a small number of low-paid and undervalued jobs. In Canada, the federal government adopted this principle under section 11 of the Canadian Human Rights Act. Over the years, section 11 came under heavy criticism due to its ineffectiveness and limited application and in May 2004 the Canadian Human Rights Commission proposed extensive reform to the federal provisions and recommended widening employers' obligations and the coverage of the pay equity legislation. This thesis addresses this reform, its adjustment to the changing nature and organization of the Canadian labour market and the possible counter-arguments concerning the efficiency of the labour market and the shift: toward deregulating the market. It also shows that equity may promote market's competitiveness and efficiency by increasing the quality of work and employees' productivity.