McGill University Thèses et mémoires publiés en 2005

Reinforcement learning is a general computational framework for learning sequential decision strategies from the interaction of an agent with a dynamic environment. In this thesis, we focus on value-based learning methods, which rely on computing utility values for different behavior strategies. Value-based reinforcement learning methods have a solid theoretical foundation and a growing history of successful applications to real-world problems. However, most existing theoretically-sound algorithms work for small problems only. For complex real-world decision tasks, approximate methods have to be used; in this case there is a significant gap between the existing theoretical results and the methodologies applied in practice. …  Read more

Anomaly A of the Clarence Stream gold deposits contains mineralized structures that bear geometrical relationships to regional folding events. Structural mapping at the regional scale reflects at least four deformational events, three of which appear to control the folded geometry of Anomaly A (D2, D3, and D4). F2 and F3 folds are in a coaxial relationship and are refolded into a dome and basin geometry by F4 folds. Structural analysis of a mineralization zone exposed at the surface indicates that gold mineralization is present within a quartz vein system that contains veins generated during both D2 and D3. Three-dimensional representation …  Read more

A sequential exploratory design (Creswell, 2003) was used to measure how a social-constructivist oriented educational psychology course could move beyond the inert knowledge Mandl, Gruber, and Renkl (1996) reported to be the outcome of student teacher engagement with formal university courses. Biggs' 3P model (Biggs, & Moore, 1993) provided the framework for qualitatively categorizing 26 student teachers' (16 female, 10 male) conceptions of meaningful learning, and allocations of responsibility for learning. Categories were tested for independence and subsequently predicted learning outcomes as identified by Bloom's revised taxonomy (Anderson, & Krathwohl, 2001). All students held qualitative conceptions of learning. Participants who …  Read more

Female genital cutting (FGC) has received much attention since the early 1980s. Decried as both a human rights violation and a barbaric example of the patriarchal subjugation of women and girls in developing nations, FGC has only recently been examined within the cultural framework in which it takes place. This thesis will focus on the Muslim communities in Egypt and Sudan who continue to engage in FGC as a required Muslim practice. Starting from the notion that FGC has a limiting effect on a woman's overall health, this thesis will use three foundational notions from Islamic medical ethics to argue …  Read more

There is no international agreement on the vertical limit of State sovereignty, the boundary between territorial airspace and outer space. The need for defining this boundary has been debated for over 50 years. Today, the need to settle this gap in the law is growing in importance. This thesis concludes that setting a low vertical limit on State sovereignty is the best approach because it will allow all States free access to space and enable uniform international rules to be set at a relatively low altitude. Chapter I discusses territorial sovereignty and examines the evolution of vertical sovereignty. It then …  Read more

Fluid visualization techniques and fluid solvers are widely used in computer graphics and scientific visualization. There is a wide variety of fluid visualization methods. We discuss in detail an important visualization technique known as the Line Integral Convolution (LIC). We perform an experiment to show how the LIC results are affected by the input parameter. We also discuss the nature of the fluid velocity field and provide a brief classification of various fluid visualization techniques. This is followed by fluid solvers, which model the dynamics of the underlying fluid and are used to generate the discrete vector field that represents …  Read more

To understand why remyelination fails in diseases such as multiple sclerosis (MS), I studied the cells and molecules involved in remyelination. I examined the cellular response to cuprizone-induced demyelination in C57B1/6 female mice. In response to the toxin cuprizone, microglia, macrophages, T cells and oligodendrocyte precursor cells (OPCs), accumulated in the corpus callosum. I have identified a novel population of CD11c-expressing microglia with potent antigen presenting capacity, which localized to the demyelinated corpus callosum following cuprizone treatment. A broad panel of chemokines were upregulated as early as 1 week following cuprizone treatment. Administration of one of them, an oligodendrocyte precursor …  Read more

Le problème de la planification de l’opération des unités de production d’électricité comprenant des spécifications des niveaux de régulation secondaire et tertiaire (celles-ci agissant sur un horizon de temps compris entre deux et trente minutes) a été amplement étudié. Le problème de planification de la production comprenant les aspects relatifs à la régulation primaire, agissant en fonction des variations de fréquence du réseau dans un horizon de temps de quelques secondes, n’a cependant reçu que peu d’attention jusqu’à maintenant. Dans ce mémoire, nous développons et solutionnons le problème de la planification de la production d’électricité en incluant la notion de …  Read more

The thermoforming process is subject to a lot of variability with regard to the viscoelastic properties of the material, and the level of residual stresses caused by the manufacturing (extrusion and calandering) process of a plastic sheet. A robust control system must be able to identify and adjust to these perturbations in real time during the thermoforming process. The research project proposes two process sub-models, which predict the behavior of the elastic modulus and the level of frozen-in stresses. These two sub-models will be used in a model based control system, consisting of a number of process submodels encompassing different …  Read more

This thesis examines shojo manga (Japanese comics for girls) as a site of the subversion of gender. The focus will be on stories about cross-dressing, as the crossdressed heroine poses from the outset questions about the nature of girls within shojo manga and the girls who are supposedly reading the texts. The analysis takes place at two levels: visual language and narrative. Over the course of five chapters, focusing on a couple of series in each, this thesis will show the various ways categories of gender and sex are undermined in five different subgenres. Yet gender norms are recuperated in …  Read more

Dominant theories of aboriginal rights articulate the relation between rights and identity in terms of a logic which treats identity as an irreducible good and rights as the instrumental means of its protection. However, identity claims and legal claims emerge in our use of language. Identity and the institutions in which identities are expressed and experienced are constituted in speech. A close analysis reveals the degree to which law and identity are a systemic imbrication of normative claims characterized by an innate indeterminacy. This indeterminacy renders all rights and identity claims contingent on their reception and validation by others.  Read more

This research examines Hemodialysis patients' psycho-social characteristics and predictors of quality of life and compliance at a small rural hospital. Sixty-four patients from the hemodialysis unit at Renfrew Victoria Hospital in Renfrew, Ontario, and a satellite unit at St. Francis Memorial Hospital in Barry's Bay, Ontario, were assessed using the Social Work Patient Profile, Perceived Quality of Life and Compliance Indices. Bivariate correlation and multiple regressions were conducted on psychosocial, physical and mental health variables to determine if they correlated, and could be predictors of, social worker and nurses' perceptions of patients' quality of life and compliance. Findings support multiple …  Read more

Human-computer interaction (HCI) is a research topic whose eventual outcome will allow users of computer systems for more natural interfaces than the traditional keyboard and mouse. Ideally, those interfaces would exploit the same communication channels used in everyday life, which are speech, gestures or any other expressive feature of the human body. In this thesis, a continuous dynamic gesture recognition system is presented. Positioning devices such as a mouse, a data glove or a video camera are used as input streams to the recognition module, from which it extracts the most interesting features. Gestures are recognized continuously, which means that …  Read more

Total body fat and muscle mass depletion has been reported in some patients with COPD. This study used simple anthropometric measurements to compare the body composition of patients with moderate-severe COPD to that of healthy controls, and examines relationships between body composition, disease severity, habitual physical activity and resting and exercise energy expenditure. Results show no significant differences in overall Heath-Carter somatotype characteristics, percent body fat, fat free mass and girth measurements between COPD and control subjects although when stratified by gender, female COPD patients exhibited a greater body fat component. Measured VO2 (L/min) at rest or during steady-state exercise …  Read more

The production of neutral meson resonances in deep inelastic scattering has been studied in DESY with the ZEUS detector at the HERA collider. The rho 0, f0(980) and f2(1270) total cross sections, as well as differential pT and eta cross sections, were measured in the 0 GeV < pT < 7 GeV and |eta| < 1 ranges. The obtained total cross sections were sr0 = 19.21 +/- 0.92 (stat.) +/- 7.59 (syst.) nb, sf0 = 0.63 +/- 0.04 (stat.) +/- 0.25 (syst.) nb and sf2 = 3.62 +/- 0.02 (stat.) +/- 1.73 (syst.) nb. The cross sections measurements for f0 …  Read more

Aguaruna Indigenous People live along the Rio Cenepa in the Peruvian Amazon. This thesis describes the Aguaruna traditional food system (TFS) and defines its nutritional importance. Nutritional status of women and young children were assessed using anthropometry. Dietary intakes and dietary diversity were recorded using repeat 24 hour recalls. Subsequently, the relative nutrient contributions of local foods were analyzed. A market survey was conducted to compare the nutrient value and relative cost of seasonal local foods with imported products. Anthropometry suggested a healthy population, although the Agauruna had short stature. They purchased <1 % of their food, and group dietary …  Read more

The term polymer brush refers to the class of structures formed by polymers when attached to a surface at sufficiently high surface density so as to cause the polymers to stretch away from the surface to avoid each other. Considering specifically brushes formed by flexible, linear homopolymers attached by a single end to an impenetrable planar surface, this thesis investigates the stability of the laterally homogeneous phase of the brush in response to fluctuations of polymer density. The controlling factors studied are: the energetic interactions of the polymers with the bath of solvent particles in which the brush is immersed; …  Read more

Mutations in the clk-1 gene of Caenorhabditis elegans result in an average slowing down and deregulation of a variety of developmental and physiological processes. In addition, clk-1 mutants are defective in responding to temperature changes. For example, wild-type worms adjust their defecation cycle length after a temperature shift whereas the defecation cycle length of clk-1 mutants is unaffected by such a shift. To understand the basis of the clk-1 phenotype, a number of genetic screens have been carried out to isolate feature-specific suppressor mutations. dsc-3(qm179) and dsc-4(qm182) were isolated in this manner. It has previously been found that dsc-3(qm179) and …  Read more

The E4orf4 protein of human adenovirus kills transformed cancer cell lines by a p53-independent mechanism. Accumulating evidence suggests that the mechanism of E4orf4-induced death is distinct from apoptosis and occurs via some novel pathway. Previous studies have shown that E4orf4 can interact with the mammalian Balpha subunit of protein phosphatase 2A (PP2A) and that this interaction is important for E4orf4-induced cell death. As PP2A is highly conserved across eukaryotic species we chose to study the effects of E4orf4 in a genetically tractable organism, Saccharomyces cerevisiae, in an effort to elucidate the mechanism of E4orf4-mediated cell death. E4orf4 expression is lethal …  Read more

Cyberpunk's attempt to imagine the futures that the expanding communications networks will shape, as explored in Sterling's Islands in the Net and Stephenson's The Diamond Age, discovers that the boundaries between the machine and human, the natural and artificial, and the past and present have never been as clear as the modern realist schematic has drawn them. Gothic literature represents transgressions of these boundaries as threatening to the self, and Mary Shelley's Frankenstein is the node where the gothic is dismembered and sutured into science fiction, and the modern self faces its monstrous double. Yet if boundaries are represented as …  Read more

With the advent of high speed interconnects, signal integrity issues resulting from incident electromagnetic fields are becoming a significant challenge for circuit designers. It is necessary therefore to be able to efficiently and accurately simulate interconnect networks affected by this type of interference in order to have a clear picture of how the signal on the interconnect is affected. Since models for interconnect networks affected by incident electromagnetic fields tend to be very large, traditional circuit simulation techniques require a significant CPU cost. In order to address this problem, this thesis introduces a model order reduction technique that allows for …  Read more

The gene capicua is required for the establishment of dorsal-ventral polarity in the Drosophila melanogaster ovary. Loss of capicua function in the follicle cells results in dorsalization of both the embryo and eggshell. The most prominent dorsal features of the Drosophila eggshell are the dorsal appendages. We show that loss of capicua function results in the ventral ectopic specification of dorsal appendage-producing follicle cell fate. This cell fate change is due in part to the ectopic expression of genes such as mirror and Broad-Complex in capicua mutant ovaries. When either mirror or Broad-Complex are ectopically expressed independently of loss of …  Read more

It is sometimes said that the Quebec model of cultural integration constitutes a third way between the French model (republican integration) and the Canadian model (bilingual multiculturalism) for addressing issues relating to immigration. The present thesis analyses that hypothesis by reviewing the history of laws related to language and religion, especially as they concern the integration of immigrants, in France, English Canada and Quebec. In parallel to those legal histories, the thesis presents some statistical data, notably to better understand the motivations of legislators and to assess the degree of conformity between social change and the policies these legislators have …  Read more

Within the framework of international trade liberalization which has given rise to considerable thought about the fundamental contribution of cultural diversity to sustainable development, we explore the upholding of the educational rights of recognized linguistic minorities and of the aboriginal and treaty rights of First Nations under the Constitution Act, 1982. We examine these rights in the light of relevant judgments of the Supreme Court of Canada in order to confirm our initial hypothesis that the highest court in the land can show governments here and abroad the steps to take to ensure that the cultural rights specific to some …  Read more

Computer theft is a mounting problem despite prevention strategies already in place. The marketplace currently offers post-theft solutions but most depend on software in place on the stolen item. This is a critical vulnerability as it places the theft recovery technology in the hands of the thief. This thesis is an investigation into the feasibility of abandoning this limitation by moving the theft recovery technology into the server, beyond the hands of the thief. The contents are divided into two complimentary sections. The first is the creation of a theft detecting DHCP server with acceptable performance levels for production environments. …  Read more

Faces provide important information necessary for social communication. The current study aimed to evaluate Event-Related Brain Potentials (ERPs) as a method of exploring face processing abilities in fragile X syndrome (FXS), a genetic disorder where social deficits lie at the core of the cognitive phenotype. Neural changes were investigated in three children with FXS across various conditions such as upright vs. inverted faces, intact faces vs. faces with no eyes as well as faces vs. cars. Relative to chronological age matched controls, children with FXS displayed greater N170 amplitudes and shorter latency peaks across conditions. In addition, the FXS group …  Read more

The vast majority of real-world data is stored using relational representations. Unfortunately, many machine learning techniques are unable to handle rich relational models. Probabilistic Relational Models (PRMs) are an extension of the Bayesian network frame work which allows relational structure to be fully exploited. They are a formalism based on relational logic for describing probabilistic models of structured data which also allow us to model uncertainty in the relationship between objects and the attributes of those objects. In this thesis we present an implementation of PRMs which allows defining conditional probability distributions over mixtures of discrete and continuous variables. This …  Read more

Localised accumulation of body fat significantly influences the development of obesity related co-morbidities and cardiovascular disease (CVD) risk. Medium chain triglycerides (MCT) have been suggested to modulate body fat distribution. Phytosterols (PS) have demonstrated unequivocal cholesterol-lowering effects. A healthy dietary solution combining MCT and PS could thus become first-line obesity and CVD prevention. The aim of this study was therefore to investigate the effects of a functional oil (FctO) rich in MCT and PS on blood lipid levels and body adiposity, compared to olive oil. Twenty-three hypercholesterolemic, overweight men, were randomly assigned, in a single-blind crossover study, to consume a …  Read more

Hermo, Louis S. (Supervisor)  Read more

This thesis addresses rheological characterization of mine tailings and paste materials as saturated solid-liquid or homogenous mixtures. Thickened tailings and paste fill can be classified as viscoplastic or time-independent non-Newtonian fluid material. Viscoplastic fluids deform plastically when the applied shear stress is less than a critical stress, which is known as "yield stress". When the shear stress exceeds the yield stress this type of fluid flows like a viscous material with finite viscosity. In terms of pipeline design for transportation of mine tailings or paste material, one of the most important rheological parameters that must be measured would be yield …  Read more

Research has repeatedly demonstrated that maltreatment increases the likelihood of criminality when compared to a non-maltreated population. What remains unclear is how maltreatment directly or indirectly affects criminality. This study was conducted to delineate any existing relationships between age of onset, type, severity and chronicity of maltreatment and age of onset, type, severity and chronicity of criminality in a Canadian context. The possible impacts of gender, parental capacity impairments, and reduced child functioning were taken into account when examining this relationship. In addition, the characteristics of these children were examined to see if there were major differences within this group. …  Read more

Injection molded parts are susceptible to shrinkage effects which undermine the strict dimensional tolerances required when they are produced. Thus, it is important to predict the conditions under which shrinkage occurs. In this work, a 3-D thermo-viscoelastic stress/strain model was used to analyze shrinkage for a flat rectangular injection molded plate under varying process conditions. Initially, the pressure, temperature, crystallinity and shear rate profiles were calculated, using an existing injection molding simulation program (McKam-IV). These data were then used to conduct the stress/strain analysis and to make shrinkage predictions for a rectangular plate represented by a 10 x 10 x …  Read more

Chemotropic cues guide the migrating axons of neurons in the developing nervous system. Netrins are bifunctional guidance cues, attracting or repelling different classes of axons. The attraction to netrins is mediated by DCC whereas repulsion is achieved through Unc5H receptors. In this thesis, we demonstrate that Rho GTPases are required for embryonic spinal commissural axon outgrowth induced by Netrin-1. Using N1E-115 neuroblastoma cells, we have found that Rac1 and Cdc42 activities are required for DCC-induced neurite outgrowth. In fibroblasts, DCC was found to trigger actin reorganization through activation of Rac1. Moreover, we show that Unc5H1 triggers actin reorganization through activation …  Read more

The dynamical stability, wave propagation, response, and mode localization in a train of flexibly interconnected rigid cylinders travelling in a confined cylindrical "tunnel" subjected to fluid dynamic forces are studied theoretically. Each cylinder, which is coupled and supported by springs and dampers, has two degrees of freedom of translational and rotational motions. The kinetic, dissipation, and potential energies of the system and the generalized forces associated with the fluid dynamic forces acting on the system, such as inviscid fluid dynamic forces, viscous frictional forces, and form drag, are obtained first. Then the equations of motion are derived by application of …  Read more

The neurotrophins are a family of growth factors involved in the survival, development, and apoptosis of specific populations of neurons and non-neuronal cells. The pro-apoptotic action of neurotrophins is, at least partially, carried out by the p75 neurotrophin Receptor (p75NTR). However the mechanism employed by p75NTR to mediate apoptosis is poorly defined. We used a yeast two-hybrid screen to find proteins involved in p75NTR apoptotic signaling. This screen led to the identification NRAGE (for neurotrophin receptor-interacting M AGE homologue), as a p75NTR interacting molecule. NRAGE is a novel member of the MAGE family of proteins, a group of molecules with …  Read more

This work is motivated by the need for test cores for advanced CMOS processes characterization, which is a key factor in process-design coupling for yield and reliability in production ramp-up. The physical properties of the Metal-Oxide-Semiconductor (MOS) structure makes of it a diagnostic tool for determining process parameters related to the technology used in the fabrication of Integrated Circuits (IC). This thesis covers a study of the existing techniques used to extract the MOS Capacitor (MOSCAP) Capacitance-versus-Voltage (C-V) curve for determining certain characterization parameters. It adds to those techniques a System-On-IC (SOIC) approach by providing a self-contained test structure that …  Read more

Structural forensic engineering is a topic that has traditionally been approached in a deterministic manner. This thesis explores the use of probabilistic procedures as a tool to obtain more objective and realistic results in forensic investigations. The first goal of the thesis is the identification of the most probable cause of a structural failure using probabilistic procedures. The second goal is to develop a procedure to qualify forensic engineers and experts according to their qualifications. In the first part, the basic qualifications required for a forensic engineer or expert are compiled in a checklist and attributed individual scores, the sum …  Read more

The effect of warm and cold rolling parameters on the development of annealing textures and their effects on the final formability were studied in two LC steels containing 0.8%Cr. Warm rolling temperatures between 640 and 750°C were employed, together with reductions of 65% to 80%. The effects of an additional cold rolling reduction of 40%, different initial hot band grain sizes (HBGSs) and a decrease in the heating rate during annealing were also studied. The ND fibre, <111>//ND, of the recrystallization texture was strengthened as the warm rolling temperature was decreased. A noticeable improvement in both the continuity and intensity …  Read more

In this thesis we study the thermal and inertia effects on atomic friction. The Friction Force Microscope (FFM) is simulated with the Tomlinson model. We introduce a method to calculate atomic friction including thermal effects. A novel scaling form is proposed and tested. We also investigate the inertial effects of the bulk and the tips. We find if the bulk is weakly damped, there is hysteresis in the velocity versus driving force curve. When the tips are weakly damped, the friction force shows large deviations. In the first half of the thesis, we study the atomic friction between an FFM …  Read more

The Salmonella typhimurium PhoP/PhoQ two-component system controls the expression of numerous genes involved in virulence. This system is activated in vivo within acidified macrophage phagosomes and is repressed in vitro in high concentrations of divalent cations such as Mg2+, Ca2+, and Mn2+ . The pho-24 allele of phoQ harbors a single amino acid substitution (T48I) in the periplasmic domain of the PhoQ histidine kinase sensor. This mutation has been shown to increase net phosphorylation of the PhoP response regulator. The mechanism by which pho-24 attenuates virulence is defined. The effect on signaling by PhoP/PhoQ of various amino acid substitutions at …  Read more

Cyclins are short-lived proteins that "cycle" through the cell cycle and determine the timing of activity of cyclin-dependent kinases (Cdks). Cyclin/Cdks regulate the progression through each phase of the cell cycle, presumably by phosphorylating key proteins. To date, only a few Cdk targets have been identified and it is not clear how Cdk complexes differ from one another. I have discovered that the CDP/Cux protein can bind to, and be phosphorylated by, several cyclin/Cdk complexes. Yet, my evidence demonstrates that each complex regulates CDP/Cux differently. The goal of my thesis is to document the interaction of CDP/Cux with several cyclin/Cdks …  Read more

Here we report the identification of 15 potential MSP-like proteins from the P. falciparum 3D7 genome using a bioinformatics-based approach. One candidate, renamed URF1, was further characterized by cloning into the Gateway system. We were able to demonstrate expression of URF1 during the blood stage, especially the trophozoite, early and late schizont phases, by immunofluorescence on infected RBC using antisera raised in mice with an URF1 DNA vaccine. URF1 expression in the merozoite stage could not be confirmed in this study. Future co-localization and immunosorbent electron microscopy (EM) experiments would help us determine the exact localization of URF1 on the …  Read more

In this thesis we present an analytical solution to the problem of improving the depth of field (DOF) of a certain large magnification imaging system with a high numerical aperture (NA), illuminated with an incoherent source of light. As there is a definite trade-off between the focal depth and resolution achievable with such a system, our challenge was to find a system that would achieve both these objectives and at the same time be cost-effective and easy to implement. Our choice of technique therefore was a novel optical wave front manipulation mechanism involving subsequent image restoration via digital post processing. …  Read more

Currently, only few XML data management systems support concurrent access to an XML document, and if they do, they typically apply variations of locking to handle XML's nested structure. However, advanced query processing techniques use a wide range of indexes and allow for arbitrary navigation through the XML documents, making lock acquisition complex and potentially leading to high blocking rates. In this thesis, we suggest two concurrency control protocols that avoid any read locks by providing transactions a committed snapshot of the data. OptiX enhances traditional optimistic concurrency control to work on XML while SnaX offers snapshot isolation as provided …  Read more

Opting for an applied theory approach, this thesis addresses various means of "compenetration" between religious normative orders and normative orders of the Quebec and French States. Based on a constructivist vision of law and on the impact of post-modernism, the thesis draws out a typology of pluralisms used in legislation with the aim to understand religious normativity (institutionalized pluralism and integrated pluralism), and distinguishes between four types of religious normativity invoked before the civil law judge, that is: the religious normativity of the State; the formal non-State religious normativity; the informal, community-based non-State religious normativity; and the personal and ethical …  Read more

As humanity prepares to migrate to the frontiers of the Moon and other planets, the area of mining in space must go along for the purpose of exploration and in-situ resource utilization. In the present work the literature that has been developed over the years in the area of mining in space as applicable to Lunar and Martian environments is reviewed. Subsequently, the key mining technologies that are most suitable for Lunar and Martian environments are identified. From the literature review, it is concluded that an optimal combination of both mechanical methods and novel energy (lasers, microwaves, nuclear energy) methods …  Read more

The complex musculoskeletal system of a running animal on horizontal surfaces act essentially like a simple pogo stick, and can be modeled as a hopping spring-mass model known as the Spring-loaded Inverted Pendulum (SLIP) model. The SLIP model has been extensively used as a reduced-order model in analysis and control of running legged robots. By contrast, the SLIP model itself has never been implemented in a robot and validated experimentally. This thesis addresses the development and validation of a robotic SLIP, a planar one-legged hopping robot with only one actuator. A feasibility study was performed using numerical simulation. The experimental …  Read more

We present a visual servoing system for an amphibious legged robot. That is, a monocular-vision based servoing mechanism that enables the robot to track and follow a target both underwater and on the ground. We used three different tracking algorithms to track and localize the target in the image, with color being the tracked feature. Tracking is performed based on the object's color, color distribution and color distribution with a probabilistic kernel. Output from the tracker is channeled to a proportional-integral-derivative controller, which generates steering commands for the robot controller. The robot controller in turn takes the steering commands and …  Read more

As an imperial city, Strasbourg has edified many monuments to promote its particular status in the Holy Roman Empire. Notre-Dame at Strasbourg is not an exception: historians read the construction of the cathedral and its facade as the materialisation of a "civic pride". Many documents, anyhow, testify to the emperors many visits and underline the city's political role in the Empire. This thesis demonstrates that the imperial presence in the Reichsstadt---events usually avoided by historians---is clearly illustrated in the iconographical and architectural programs of the cathedral. The selection of biblical scenes and protagonists, historical figures, and the borrowing of architectural …  Read more

The X-ray crystal structure of the protease subtilisin shows its active site is on the surface. It binds substrate in an extended conformation and reacts only with soluble substrates. Subtilisin has a large nonpolar pocket (the S1 pocket) to bind acyl group and a shallow crevice (the S 1' pocket) to bind one substituent of a secondary alcohol group, while the other substituent remains in solvent. The reactivity and enantioselectivity of subtilisin toward nonpolar secondary alcohol esters is low. Based on its structure, we hypothesized that subtilisin would be highly reactive if the acyl group anchored the substrate to the …  Read more