McGill University Thèses et mémoires publiés en 1981

In this thesis it is shown that several pattern recognition problems can be solved efficiently by exploiting the geometrical structure of the problems. The problems considered are in the area of clustering and classification. These problems are: (i) computing the diameter of a finite planar set, (ii) computing the maximum and minimum distance between two finite planar sets of points, (iii) testing for point inclusion in a convex polyhedron in d-dimensional space, and (iv) exact and inexact reference set thinning for the nearest neighbor decision rule. Algorithms to solve the above problems are presented and analyzed for worst-case and average-case …  Lire la suite

A three year study on Daphne Major island, Galapagos, describes the ecology and morphology of a simple Geospiza community. The four part thesis discusses the breeding and feeding ecology of two Daphne finches; G. fortis is a generalist adapted to a variable environment, and G. scandens is an ecological specialist experiencing a more stable environment. The measurement, growth, allometry, and multivariate properties of seven external morphological characters are described. The repeatabilities and heritabilities of the seven characters and principal component scores are large. Relations between the unusual intermediate-sized Daphne G. fortis phenotype and the Daphne environment are examined. Four hypotheses …  Lire la suite

This thesis presents a critique of the sociotechnical approach based on a case study of sociotechnical "quality of working life" intervention undertaken in the plant and office of Thompson Building Supplies* (TBS) Ltd., a Canadian firm which produces building materials. From March 1979 through November 1980, I was employed as resource person for the office project. Following a severe downturn of the business cycle, the project was terminated before its completion in late 1980. […]  Lire la suite

Bider, J. R. (Supervisor)  Lire la suite

Laferrière, Professor M.  Lire la suite

Neisseria meningitidis (SD1C) when grown in an iron-limited medium at low pH exhibited a dramatic increase in virulence for the mouse. This enhanced virulence correlated with a specific colonial type, and altered outer membrane protein profile, the expression of an uptake sytem for iron from human transferrin, and an increased resistance to phagocytosis by mouse polymorphonuclear leukocytes. The outer membrane of cells grown at pH 6.6 contained a 69,000 molecular weight protein (protein III) that was exposed on the cell surface. The outer membrane of iron-limited cells grown at pH 7.2 also exhibited protein III, but cells grown at pH …  Lire la suite

Eisenberg, Adi (Supervisor)  Lire la suite

Nous avons accomplis une analyze de désintégration en séquence pour la réaction rr - p 0 ~ wrr n a une impulsion incidente de 8.45 GeV/c dans une expérience exécutée au synchrotron du Argonne National Laboratory. Les propriétés de production et de désintégration du méson B0 sont présentées ainsi que la section efficace différentielle pour la réaction rr-p - B0 n. Nous présentons de l'évidence sur la présence du méson p'(l250) (IJPC = 11--). Notre étude sur la production du B0 indique que l'échange de A2 domine (changement d'orientation du spin de nucléon) Nous avons trouvé de quantité significatif d'onde …  Lire la suite

Three reaction time experiments were conducted to determine when and how memory for the normal left-right orientation of letters is mediated by the developing brain. In each experiment, participants identified forward and backward letters presented unilaterally to each visual field and thus to each hemisphere (VF-H). The main findings were as follows: (1) For the five-year-olds, no VF-H differences were found in the speed of identifying either forward or backward letters or in the difference in speed between forward and backward letters. (2) The seven-year-olds identified forward letters faster than backward letters in the right visual field-left hemisphere (RVF-LH) with …  Lire la suite

During the past decade film analysis and semiotic inquiry have meshed to produce significant changes in film theory. This thesis discusses the philosophical and epistemological shift represented by this development, resulting in the creation of semiotic models (e.g. those of Christian Metz and Umberto Eco) which consistently overemphasize the textual framework for cinematic expression. As a result, problems of performance and interpretation are ignored. The thesis proposes a radically different strategy to explain meaning in film. To solve problems of performance the new concept of projections is proposed. Projections are defined not as images or pictures, but as sites (or …  Lire la suite

"La religion" n'a pas réussi comme concept dans l'anthropologie traditionnelle puisque ses approches invitent l'intrusion des évaluations propres du chercheur sur ce qui est "surnaturel" ou "sacre" et ce qui ne l'est pas. La définition opérationnelle proposée ici est dérivée principalement de sources anthropologiques et philosophiques. La religion est "l'ensemble des hypothèses formant la base du système cognitif de l'individu; de telles convictions sont évoquées en insistant sur la question "pourquoi" jusqu'à ce que le sujet indique le caractère impropre de la question." L’effet de cette approche 'est "d'objectiver" la concept de la religion. Évoquer des convictions rastafariennes a New …  Lire la suite

Dorsinville, M. (Supervisor)  Lire la suite

Rabbits with experimentally-induced inflammatory and degenerative arthritic lesions were examined for the development of immunity to homologous collagens and cartilage proteoglycans. Cellular immunity, assessed in vitro by the stimulation of ('3)H-thymidine incorporation into spleen and blood lymphocytes, could be detected to types I, II and III collagens and proteoglycans. The responses to collagens were primarily detected with degraded molecules whereas responses to proteoglycans could be detected with both native and degraded preparations. Anti-proteoglycan antibodies could be detected in the sera of rabbits with inflammatory, but not degenerative, arthritis. Anti-collagen antibodies were never detected. Cellular, but not humoral, immunity to proteoglycans …  Lire la suite

Immune mechanisms underlying the non-rejection of the allogeneic fetus and the placenta were investigated. Whether paternal type Class 1 major histocompatibility (MHC) antigens, which were detectable on dispersed trophoblast cells of the placenta, were sequestered away from the maternal face of these cells in vivo, was examined radioautographically after a local arterial perfusion of the placenta with ('25)I-labeled monoclonal anti-H-2K antibody. The results revealed significant and specific labeling of the sinusoidal face of labyrinthine trophoblast cells, in direct contact with maternal blood. However, trophoblast cells examined radioautographically after exposure to polyspecific or monoclonal anti-Ia antibody revealed a paucity of cell …  Lire la suite

Groffier-Atala, Ethel (Supervisor)  Lire la suite

The solute strengthening due to oxygen in Zircaloy-2 was investigated over the temperature range 1023 to 1873 K. The flow stress was determined in constant true strain rate hot compression over the strain rate 10('-4)-10('-1)s('-1). In order to provide data for LOCA modelling, the 0 concentration range 1260 to 12360 ppm was investigated. For the single phase (alpha) and (beta) materials, the flow curves were normal, whereas the ((alpha)+(beta)) materials exhibited significant yield drops and strain aging, especially when over 50 vol.% (beta) was present. These effects are attributed to the enrichment of the (beta) phase by the solutes Fe …  Lire la suite

Employing successive chromatography on DEAE-Sepharose and on single-strand (ss) DNA-cellulose, a new form of Neurospora endo-exonuclease has been isolated, a Mg('2+)-dependent ss-DNA-binding endo-exonuclease. The enzyme has been purified to homogeneity from extracts of mitochondria, vesicles, and the "25,000 xg pellet" (a mixture of mitochondria and small vesicles) indicated by the appearance of single protein bands on non-denaturing polyacrylamide gels and the same specific activity (14,000 U/mg) for enzyme from all three sources. The apparent native molecular weight for the endo-exonuclease from vesicles and the 25,000 xg pellet was 80K, but for the enzyme from mitochondria it was 116-130K. The mobility …  Lire la suite

The interactions of a linguistically mixed teaching staff of an immersion school in Montreal were explored to determine their influence on the integrative objectives of immersion programs. Teachers' formal and informal interactions were observed to feature the predominant use of English and the use of silence to avoid code switching and functioned to manage conflict to the detriment of integrative immersion goals. Conflict among the staff arose from disagreements about immersion programs, conflicting societal and professional norms and the school's organizational divisions. A projective technique was used to determine if perceptions of linguistic norms of 176 grades 1 to 6 …  Lire la suite

The year 1759 saw the arrival in Paris of the abbe Galiani as secretary to the Neapolitan Embassy. His initial feelings of disappointment diminished as he was welcomed in the most important salons of Paris, where he met the principal Encyclopedistes, including Diderot. This thesis is a thorough study of the intellectual and human association between Diderot and Galiani: the circumstances of their encounters, especially between 1760 and 1769 when Galiani was forced to return to Naples; their mutual friends, and the areas of common interest which attracted these two encyclopaedic minds, such as literature, especially the theatre, the arts …  Lire la suite

The inoculation of Aspergillus flavus spores into a culture of Streptococcus lactis in LTB medium resulted in none or little aflatoxin production even though growth of the fungus was not hindered. The drop in pH and reduced nutrients in the medium as the result of S. lactis growth were not the cause of the observed inhibition. The inhibition was not eliminated by the addition of carbohydrate equal to the amount utilized by the bacterium prior to the inoculation with the fungus. Aflatoxin production was also inhibited when S. lactis was inoculated after A. flavus had grown. In addition to inhibiting …  Lire la suite

Scriver, Charles R.  Lire la suite

This thesis presents an analysis of a learning situation of positive and negative integers. It is considered as a case study within the more general context of the development of school learning analysis tools based on cognitive psychology. An analysis of error patterns obtained from a group of 55 secondary I level students has shown: (1) that the acquisition of the integer concept can imply several levels of integration of the sign and the numerical aspect; (2) that the set of all possible addition and subtraction items can be classified according to their possibility of being related to previous numerical …  Lire la suite