VictorJuiz/thesis huggingface dataset:
X-ray crystallographic analysis of 1) the two N-terminal domains of epithelial cadherin and 2) C3d, a fragment of the complement protein C3

This thesis will present two protein structure determinations by x-ray crystallography and a methodological development. The first structure is of the two extracellular N-terminal domains of E-cadherin (Ecad12), a developmentally regulated cell adhesion molecule that mediates Ca2+-dependent cell-cell contacts. The structure reveals a two-fold symmetric dimer, each molecule of which binds a contiguous array of three bridged calcium ions. The calcium ions serve not only to rigidify the molecule into a linear conformation, but they also promote dimerization. The Ecad12 structure provided the first atomic level view of the role of calcium in the cadherin mediated formation and maintenance of solid tissues. The second structure was that of C3d, a proteolytic fragment of the central complement component C3. Activation and covalent attachment of C3 to pathogens is the key step in complement-mediated host defense. Additionally, antigen bound C3d interacts with complement receptor 2 (CR2, CD21) on B cells and thereby contributes to the initiation of an acquired humoral response. The structure of C3d reveals an Ã-Ã barrel with the residues responsible for covalent attachment at one end of the barrel and an acidic pocket well-suited to interact with CR2, at the other end. The structure supports a model whereby the transition of native C3 to its functionally active state involves the disruption of a complementary domain interface. Finally, the methods chapter describes a novel set of programs that provide a means for combining phases from slightly non isomorphous sources and extending them to higher resolution. The process of freezing the Ecad12 crystals caused non-isomorphism between the various data sets. Conventional density averaging and phase combination between the data sets could not be performed because of the poor quality of the electron density maps from two of the data sets (in part due to missing data). Application of the procedure to the Ecad12 case transformed the initial low resolution/quality electron density map into an easily interpretable map that contained continuous density with higher resolution side-chain information.
L'oubli dans la création littéraire, l'exemple de Marguerite Duras, Christoph Hein, Milan Kundera et Christa Wolf

Les quatre auteurs soumis à cette étude proposent, par le biais de leurs création littéraires, un discours commun de la représentation du passé. Dans 'L'Amant' (M. Duras), 'L'Ami étranger' (C. Hein), 'Le Livre du rire et de l'oubli' (M. Kundera) et 'Trame d'enfance' (C. Wolf), le passé est abordé comme une masse toujours déjà problématique pour l'instance narrative en question. Cette étude souligne d'abord l'emploi de la photographie en tant qu'outil narratif dans les quatre récits afin d'insister sur le caractère artificiel de toute représentation du passé. Pour ce faire, la photographie est abordée comme moyen de subvertir la représentation du passé et non comme confirmation de l'événement. Ensuite, l'étude entreprend de délimiter la relation entre la mémoire collective et la mémoire personnelle. La mémoire et ses fondements sont abordés, à travers le vocabulaire freudien, comme des données malléables au discours. Il s'agit de mettre en cause l'existence même de la mémoire collective. Finalement, cette étude présente les limites et la possibilités de la fiction quand elle tente de représenter le passé du groupe ou de l'individu. Fiction et écriture de l'histoire s'entrecroisent ici pour souligner que l'événement a été oublié malgré les efforts des instances narratives pour ancrer leurs récits à des référents d'ordre personnels, historiques, familiaux et ainsi de suite. Il sera possible de définir les motivations de l'oubli volontaire dans la création littéraire qui s'inscrit à l'opposé du devoir de mémoire. Aussi l'écriture de l'oubli reste tributaire des métaphores spatio-temporelles sur lesquelles elle repose. L'oubli et la mémoire s'inscrivent dans le temps et dans l'espace dans des perspectives variées de distances et de déplacements discursifs. En filigrane à cette étude, la réponse à la question: qu'est-ce que le l'écriture de l'oubli et de quels procédés littéraires relève-t-elle?
The effect of material preactivation of platelets on deposition

The effect of shear on platelet activation was investigated and characterized. It was found that the residence time had a more significant effect on microparticle, MP, generation in the sample than the applied shear rate. Platelets were also activated by alternative methods, such as incubation with glass beads, to induce MP generation. Samples which produced large MP concentrations during activation were found to deposit fewer platelet on the polyethylene, PE, tubing than the rest sample. Further characterization of the material activated platelets revealed that material contact did not result in significant loss or activation of GPIIbIIIa on the platelet surface. Nor did material contact result in the upregulation of P-Selectin to the platelet surface. Samples which produced the greatest number of MP during activation experienced impaired sensitivity to platelet agonists such as thrombin peptide, collagen and ADP. Therefore, platelet microparticles may be markers of reduced platelet function as well as platelet activation.
Leadership in higher education, towards alternative constructs of administration, organization, and knowledge

Leadership evokes ambivalence. As a term, as a human activity, and as a social practice, leadership is familiar yet imposing; it is sought after but regarded apprehensively; it inspires admiration while eliciting misgivings; it is, in short, equally winsome and worrisome. Given the aspirations of democracy and egalitarianism integral to the Occidental worldview, our consternation about leadership and leaders seems essentially irresolvable. Within the context of education, the ambivalence surrounding leadership is heightened. In the school, the college, and the university, where a professional collegiality has shaped practices peculiar to such organizations, "educational leadership" and the administrative mastery it implies can seem oxymoronic, if not simply illusory. Yet calls for renewed leadership as a crucial element of educational improvement continue unabated. This dissertation is an attempt to make leadership and the paradoxes it evinces comprehensible. The form of leadership examined is that which is implicit in the administration of educational institutions. The institutions, in this case, are contemporary Canadian universities, and the administrative practice is the university presidency. The underlying premise is that leadership and the organizations in which it is actualized are social constructs, as is the knowledge we may have of each. The argument made is that our established vocabularies may needlessly and unhelpfully limit the kind of conversation we might have about administration, organization, and knowledge, and, therefore, that these vocabularies need revision, and, perhaps, replacement. The pragmatic recognition that knowledge is made narratively from vocabularies imbued with cultural and historical contingencies, contextualizes the conversations with five practicing university presidents that are the primary data for this study. The information collected through interviews and questionnaires and the hermeneutic context of its appreciation make possible broader speculation about the nature of leadership as an inescapably moral praxis, and of administration as an ambivalent cipher for the control of individual and organization. This speculation inevitably speaks to the prospects of our cultural moment and to the modernist preoccupation with mastery, that, as I argue, drives this moment forward.
Continuous analysis of stormwater quality control ponds with derived probability models

The impacts of urbanization on the environment, and particularly on the natural drainage system, have been well documented. Many structural and non-structural control measures exist to address the quantity and quality of runoff from an urban area. Of these, extended detention dry ponds and wet detention ponds continue to be effective end-of-pipe stormwater management facilities. However, designing these facilities is not a simple task. There is a need for a planning or screening level model which can provide a quick, reliable estimate of the performance of a stormwater management pond. Analytical probabilistic models are capable of assuming this role. In this thesis, a new analytical model is developed for the analysis of wet and dry detention ponds for quantity and quality control. Improvements are made over previous analytical models developed at the University of Toronto, resulting in better agreement with continuous simulation model predictions.
Greek & the Internet, the affects of electronic mail exchange on the Greek language

The Greek language seems to be one of the minor languages on the Internet. The fact that Greek is not always recognized by computers, because of its alphabet characters, has led Greek-speaking Internet users to create another script, a hybrid language called "Greeklish", which is a transliteration of the Greek language in Latin characters. However, this kind of script has started an immense argument between academic circles in Greece, who believe that it could be a threat to the historical Greek language. In this exploratory study I present the results of a survey conducted on the Internet, and I try to analyze further the growing phenomenon of "Greeklish", as it is today.
Signaling pathways of the endogenous glucagon-like peptide-2 (GLP-2) receptor

GLP-2 increases small intestinal (SI) mass and crypt cell proliferation. Paradoxically, the GLP-2 receptor (GLP-2R), which signals via cAMP, has been found only in endocrine cells in the human gut. The endogenous GLP-2R is not expressed by any known cell line, but is expressed by isolated rat SI mucosal cells that we collected along the crypt-villus axis. Based upon sequence similarity between the GLP-2R and related G protein-coupled receptors, we hypothesized that the GLP-2R desensitizes and activates MAPK and Ca2+ signaling. We report that the endogenous rat GLP-2R responds maximally to physiologic doses of GLP-2 and desensitizes to high doses. GLP-2 does not activate Ca 2+ or MAPK in isolated SI cells, but activates MAPK in whole SI mucosa. Given the location of the GLP-2R in endocrine but not crypt cells, these findings suggest that the intestinotropic effects of GLP-2 are mediated by factors released downstream of GLP-2R activation.
Experimental studies and theoretical modelling of an unsteady state biofilter used to treat fluctuating concentrations of an Ã-pinene air emission

This research describes the biofiltration of a transient, Ã-pinene laden air emission and compares experimental results to a dynamic diffusion-reaction model for a plug flow reactor. Three parallel biofilters, two biofilters (replicates) treating a cyclically fluctuating concentration and the third biofilter treating a constant concentration, were used to study the effect of periodic concentration fluctuations on biofilter performance. The cycle period ranged from 10 minutes to 6 days, with maximum Ã-pinene concentration fluctuations between 0 to 100 ppmv. Both cyclic (cycle period of 10 minutes) and constant concentration biofilters maintained similar long-term performance (averaging removal efficiencies of 77%) at an averaged loading rate of 29 g Ã-pinene/m3 bed/h. The dynamic model, using kinetic parameters estimated from the constant concentration biofilter, was able to predict the performance of cyclically operated biofilters operating at short cycle periods (i.e., on the order of minutes and hours). As a first approximation, steady state kinetic data from a constant concentration biofilter can be used to predict unsteady state biofilter operation. At a 24 hour cycle period, the dynamic model compares well with experimental results. At longer times scales the model does not effectively predict transient behaviour as adsorption and changes in kinetic parameters are not accounted for. For long cycle periods (i.e., hours and days), removal efficiency decreased after periods of non-loading; the longer the period of non-loading, the poorer the biofilter's performance at the re-commencement of pollutant loading. The recovery time for a cycle period of 24 hours was less than one hour. The recovery time for a cycle period of 6 days was between 6-8 hours. Modelling results showed that similar biofiltration performance for cyclic and constant concentration biofiltration of Ã-pinene is expected for biofilters operating solely in the first order kinetics regime. Poorer performance for cyclic biofilters following Monod kinetics spanning the entire kinetics range is expected as the cycle amplitude increases. The most important parameters affecting the performance of a cyclically operated biofilter with short cycle periods are: amplitude of cyclic fluctuations, Cg,max/Cg, relative value of the half saturation constant in the Monod expression, K s, and effective diffusivity of Ã-pinene in the biofilm, D e.
Filamentous actin disruption and diminished inositol phosphate response in gingival fibroblasts caused by Treponema denticola

Treponema denticola causes actin rearrangement in human gingival fibroblasts (HGF). I hypothesized that there was a treponeme-induced disturbance in the polyphosphoinositol signal transduction pathway in HGF. The purpose of this investigation was to determine the effect of T. denticola on inositol phosphates (IPs) in relation to stress fiber disruption in HGF. Stress fibers were stained with rhodamine-phalloidin. Exposure to T. denticola caused an increase in the number of HGF showing altered stress fiber patterns by 60 min and a corresponding reduction in the total fluorescence. T. denticola outer membrane (OM) extract caused a similar stress fiber disruption. Challenge with different strains and species of treponemes, and the OM extract resulted in a diminished accumulation of IPs within 60 min relative to controls. Pretreatment with proteinase inhibitors did not reverse the stress fiber disruption and the diminished IP response. Therefore, T. denticola expresses cytopathogenic activities, which are distinct from proteolytic activities. Such cytopathogenic activities lead to diminish IPs generation and are associated with cytoskeletal disruption in infected fibroblasts.
Studies on the mechanism of action of New Pressor Protein, bradykinin, pituitary adenylate cyclase-activating polypeptide and adrenal catecholamines as possible mediators of its cardiovascular effects

Enzymic "New Pressor Protein" (NPP) from human plasma shares homology with the active beta fragment of human coagulation factor XII (ßFXIIa) and raises blood pressure (BP) and heart rate in bioassay rats. Concurrently, it also triggers a substantial release of adrenal catecholamines, especially adrenaline. The cardiovascular effects of NPP are potentiated by the ACE inhibitor (ACEI) Captopril, as well as by ganglion blockade, thereby suggesting that the adrenal effects are mediated by a "peptidergic pathway", rather than by sympathetic cholinergic mechanisms. Two peptides, bradykinin and pituitary adenylate cyclase-activating polypeptide demonstrably mimicked NPP's cardiovascular actions, but administration of their antagonists only partially blocked NPP, suggesting that other mediators are also involved. Results from this project demonstrate that NPP/ßFXIIa may represent a novel axis connecting blood coagulation to endocrine pathways, adrenal medullary function and BP regulation that may interfere with and counteract the normally beneficial effects of ACEIs.
Technical change, international trade and inequality

My dissertation examines the impact of technical change and international trade on wage inequality between skilled and unskilled labour. I address a number of puzzles, though one stands out. The Stolper-Samuelson theorem predicts that globalization will increase inequality in developed countries (the North) while decreasing inequality in developing countries (the South). Yet this is not what we observe. Inequality has been rising even in some Southern countries! In the first essay I use the Dornbusch-Fischer-Samuelson variant of the Heckscher-Ohlin model (QJE, 1980) to describe what happens when the North is the source of product innovation. I show how international trade creates general equilibrium incentives to transfer technology to the South. Since these transfer incentives are greatest for the least skill-intensive goods produced in the North, technology transfer reduces the relative demand for unskilled workers in the North, thus raising Northern inequality. From a Southern perspective, however, these transferred technologies are relatively skill intensive. Thus technology transfer raises the demand for skilled workers in the South, increasing Southern inequality. Contrary to the predictions of the Stolper-Samuelson theorem, Northern product innovation induces technology transfer of a form that raises inequality in both the North and the South. In the second essay I examine my theory's empirical relevance using very detailed (5-digit SITC) trade data. Just as predicted by the theory, I document the existence of a sequence of product cycles that are associated with skill upgrading (i.e., increasing employment of skilled workers in production processes) in producer countries. This sets the stage for an econometric analysis of the causal impact of product-cycle-driven technology transfer on skill upgrading across 28 countries and 28 industries. Issues of country fixed effects and endogeneity are addressed. The conclusion is that product-cycle-driven technology transfer can explain a significant portion of skill upgrading in both high-income and middle-income countries. My third essay uses the Dornbusch-Fischer-Samuelson variant of the Heckscher-Ohlin model again to explore additional issues surrounding exogenous Southern catch-up and skill biased technical change. It makes the simple point that trade provides a channel through which Southern catch-up can induce rising inequality not only in the South, but also in the North. Furthermore, contrary to the conventional view, Southern catch-up will increase real national income in both the North and the South.
Application of the Chinese Postman Problem model to the Toronto transportation network within GIS-based software

The theory of transportation networks as a discipline has been developing for decades, always evoking interest in researchers around the world. Depending on the transportation network's design and on the organization of the transportation on the network, infrastructural costs, and the costs related to providing transportation can be greatly reduced on the one hand and the level of service increased on the other. Therefore, the application of existing theoretical models, their modification depending on the characteristics of the network, and the creation of new models can not only improve the level of service but also considerably increase economic productivity of the entire transportation system. In order to make a contribution to the application of the variety of theoretical ideas developed with the respect to a transportation network, this project presents the author's development of a model for solving the Chinese Postman Problem utilizing a Geographic Information System tools and then of its application to a transportation network.
Novel multimode fibre gratings for medical Raman spectroscopy

We present analysis of a novel multimode fibre tailored to allow the creation of fibre Bragg gratings with narrowband, high reflectivity, response. The proposed fibre consists of concentric cylindrical shells of higher and lower refractive index material. Modal propagation characteristics, and their dependence on fibre structural parameters, are examined using finite element analysis. Grating simulations show a reflection response with a 10 -4[lambda] bandwidth is possible when power is launched into modes with harmonic mode parameter of p = 1. An analysis of mode population distributions for excitation by different source geometries is presented. Consequently, a probe geometry is presented for use in Raman Spectroscopy. Simulations of coupling between tissue-scattered light and the proposed probe show that coupling efficiency of the probe is on the order of 10-3, a value comparable to, or greater than, existing probes. Experimentally determined coupling efficiencies on fabricated fibres are shown to have good agreement with theoretical calculations.
Postsynaptic density-95, PSD-95, trafficking of the dopamine transporter to the plasma membrane

The regulation of the dopamine transporter involves protein kinase C phosphorylation, resulting in its being trafficked to and from the cell membrane. It was found recently that the PDZ domains of PSD-95 binds the carboxy-terminal of shaker-type K+ channels to cluster the channels at specific regions of the neural membrane. To look into this possibility as a method of dopamine transporter regulation, [3H]dopamine uptake and confocal studies were done. The presence of PSD-95 increased both Km and Vmax of the human dopamine transporter while confocal studies showed an increased proportion of transporters at the cell surface when PSD-95 was present. This suggests that PSD-95 is involved in the trafficking of the human dopamine transporter to the cell membrane. In addition, PSD-95 had no effect on the uptake of a carboxyl-terminal truncated dopamine transporter which suggests that the carboxyl-terminal is involved in an interaction with PSD-95 to elicit its effects.
Incongruity, humour and early English comic figures: Armin's natural fools, the Vice, and Tarlton the clown

This thesis explores how Early English comic figures made their audience laugh. It focuses on Robert Armin's descriptions of natural fools, the figure of the Vice in the moral interludes, and Richard Tarlton. In my first five chapters, I establish a working theory of humour which is founded on the incongruity theory tradition, but also incorporates classical superiority theories, and Freud's relief theory. I propose that an incongruity which is simultaneously congruous from an alternate perspective, is the basic mechanism of all humour. This mechanism is related to the psychological processes by which we conceive the world and ourselves in the world. In fact, our conceptual systems of necessity create paradoxes and disjunctions which are potentially humorous. This thesis explores the ways in which Armin's natural fools, the comic Vices and Tarlton the Clown operate in this ambiguous territory in order to create the dynamics of their comedy. For their contemporaries, the natural fools represented a disjunction between the notions of man and animal, and adult and child. The laughter directed at the natural was one way in which his contemporaries defined themselves as human and as socially competent adults. Although the fools are the targets of disparaging laughter, they are also the objects of great affection. The paradoxical nature of humour means that the laughter directed at the fools must of necessity be both inclusive and exclusive. The Vice creates comedy by playing upon his Christian audience's emotionally contentious relationship with morality. The audience's laughter is a recognition of the disjunctions created by the conflicting impulses of their souls and their bodies. To make his audience laugh, the Vice redefines his evil as fun. The laughter in the moral interludes thereby becomes morally ambiguous. Tarlton achieved great popularity through the professional pursuit of ambiguity. By playing both comic victim and comic hero, he encouraged a multiplicity of responses from his heterogeneous audience. He was society's designated funny man and by making people laugh, he empowered himself. Paradoxically, he only achieved this power by presenting himself as an outsider, as society's lowest common denominator.