McGill University Thèses et mémoires publiés en 1989

Pseudomonas pictorum can deplete serum cholesterol. Cholesterol depleted includes free cholesterol, esterified cholesterol and cholesterol bound to different lipoproteins. Temporarily accumulated cholestenone was metabolized as reaction continued. The reaction kinetics controls the global cholesterol depletion rate during the initial part of the fermentation. Then, mass transfer takes control. In the latter, the global rate was first order with respect to the cholesterol concentration and zero order with respect to the bacterial concentration. The half time was 330 min. The activation energy was 83 kJ/mol. These results are consistent with the aqueous cholesterol diffusion model. P. pictorum was immobilized in alginate …  Lire la suite

Research in social comparison conducted with male subjects, strangers, and acquaintances has shown that unfavourable comparisons between highly similar individuals result in a negative self-evaluation, dissatisfaction, and decreased liking for the comparison other. Two studies were conducted on comparisons between 16-18 year-old female friends who perceived each other as high or middle in similarity in order to test the generality of these findings for close friends. Subjects were given false feedback on a test of maturity and told that they were at level 4 out of 8 while their friend was at level 6. The first study indicated that social …  Lire la suite

Matrix glass transition temperature depression through internal plasticization of a styrene-sodium methacrylate ionomer resulted in enhanced clustering at low plasticization levels (up to ca. 20 mole%). At higher plasticization levels, ion aggregation was strongly disrupted. Matrix polarity effects were studied by nitrating the styrene units of the same ionomer. A sample with a relaxed dielectric constant comparable to acrylate polymers showed no decrease in clustering. Similarly, plasticization with nitrobenzene resulted in typical nonpolar diluent behavior. Polarity was, therefore, not a significant parameter affecting ion aggregation. New styrene copolymers with substituents R = $-$(CH$ sb2$)$ sb{ rm n}$COOMe (n = 1, …  Lire la suite

This thesis is concerned with the manuscript of the memoirs of Dov Ber Birkenthal, Ber of Bolechow. The memoirs describe Jewish existence in eighteenth century Poland and provide valuable information regarding economic, social and cultural matters of that era. Uncovered in 1912, the manuscript was edited and published in Hebrew and translated into English by Dr. M. Vishnitzer. By primary supposition of the present thesis is that Dr. Vishnitzer's transcription of the manuscript is inaccurate, and for this reason, a re-working of the memoirs has been undertaken. In addition to providing an authentic transcription of the manuscript, this thesis also …  Lire la suite

We hypothesize that continuous electrical stimulation (ES) of denervated muscle using implanted electrodes and a pulse generator lessens the effects of denervation and helps to preserve muscle integrity. Ten dogs underwent sciatic nerve severance, common peroneal nerve repair, and implantation of stimulating devices. The proportion of muscle weight preserved was significantly greater in the stimulated muscle than in the untreated denervated muscle (p $<$ 0.01). There was evidence of less atrophy and degeneration in DS seen in both light and electron microscopy. Dependent t test analysis using the normal contralateral muscle groups as the control showed that twitch contraction time …  Lire la suite

A sample introduction system was developed with the goal of improving the efficiency of introduction of slurries into an inductively coupled plasma for atomic emission spectrometry. The system consisted of a Legere nebulizer with a heated spray chamber followed by a condenser. A capillary injector tube of 1.0 mm i.d. was required to minimize the signal variations caused by fluctuations of the injection gas. Comparing with a conventional slurry system, the hot system increased the transport efficiency by 2 for liquid and solid samples while it decreased the water content of the aerosol by 38%: 9.3 mg/min compared to 14.8 …  Lire la suite

A novel simulated food model (ascorbic acid, thiamine and a mixture of glucose and glycine) incorporating celite was developed. Basic kinetic parameters were established and the analysis of this data led to a reconsideration of the fundamental aspects relating the TDT and Arrhenius systems of evaluating kinetic parameters and their meaning. Heat penetration data was obtained for both conduction and convection systems, with the conduction system being characterized by parameters calculated from the heat penetration data. Stainless steel micro-capsules were used to isolate and obtain centerpoint nutrient destruction and compared it to the predictions of two computer models. Computer models …  Lire la suite

Bradley, Martin A. (Supervisor)  Lire la suite

Norton, David (Supervisor)  Lire la suite

An X-band transmitter ($ lambda$ = 3,2 cm) should perform better than an S-band transmitter ($ lambda$ = 10,4 cm) in the remote measurement of snowfall by radar. Comparisons between groundtruth measurements and their radar measured counterparts are done for two similar snowstorms (November 20th and 21st 1986, January 30th and 31st 1987), scanned respectively with an S-band and an X-band transmitter, mounted on the 10 m wide antenna of the Weather Radar Observatory of McGill University; these observations confirmed the hypothesis. A mixed rain-snow precipitation event was also observed on February 21st 1989, using alternatively the X-band and the …  Lire la suite

The access tunnels for the Donkin-Morien Mine in Cape Breton, Nova Scotia comprise two parallel tunnels driven through a sedimentary sequence of sandstone, siltstone and mudstone to intersect the Harbour Coal Seam under the Atlantic Ocean, approximately 3.5 km offshore. During the period May 1983 to December 1984, a geotechnical research programme was carried out in the Donkin-Morien tunnels by Golder Associates Ltd. The research programme included the monitoring of the performance of the TBM and drill and blast drivages, and the study of the thrusting characteristics and rock-interaction of the TBM excavation. The main emphasis of the research programme …  Lire la suite

The fetal liver plays an important role in hemopoiesis during mammalian development. Morphological and immunocytochemical studies were carried out to identify and characterize cellular components that may be responsible for producing the liver hemopoietic environment. Cytospot preparations, from fetal livers of 11-18 days gestation, reacted with specific antibodies enabled us to characterize and quantitate the different cell populations. Light microscope observations also showed areas of close cell associations involving two classes of central cells and peripheral erythroid cells. Such associations were distinguished based on their immunocytochemical characteristics (AFP vs. Mac-1 central cells) and quantitative appearance throughout cytospots. The presence of …  Lire la suite

Fluoride ions smoothly destannylate organotin oxides, sulfides and selenides to liberate highly nucleophilic species ("S$ sp{2-}$", RS$ sp-$, RO$ sp-$, RSe$ sp-$, etc.). Also, the first nucleophilic oxide "O$ sp{2-}$" and selenide "Se$ sp{2-}$" transfer agents are reported. The tin atom thus serves as a general "group 16 (VIB) transfer agent". In the presence of crown ethers or ammonium salts, this process results in a new way to generate "naked" nucleophiles. Novel anhydrous fluorinating systems (CsF and crown ethers) involving solid-liquid phase transfer catalysis have been designed and studied. In addition, C-C bond forming reactions have been investigated by fluorodestannylation. …  Lire la suite

This inquiry suggests a new epistemological foundation for understanding and discernment in biomedical ethics. This foundation, based on Aristotle's phronesis or practical wisdom, contains elements of the lived human experience which are seen as essential aspects of ethical, as well as medical, deliberation. The Aristotelian intellectual virtues of theoria and phronesis, used as "ideal types" of rationality, provide epistemological prejudices that structure two distinct ways of thinking. With this distinction, an alternative to certain dominant trends within biomedical ethics arises as phronesis provides more human centered prejudices for understanding. In conclusion, we shall see, using the doctrine of informed consent, …  Lire la suite

The objective of this research was to study the relationship between stillbirth and chemical exposure of pregnant workers. A case control study was conducted among women working in three sectors: Health, Personal services and Agriculture, and Manufacturing industries. Two hundred and twenty-seven (227) stillbirths aged 20 weeks of gestation or more, were matched to two hundred and twenty-seven (227) livebirths, for mother's age, gravidity and socio-economic status. Chemicals were divided into ten (10) groups. Exposure was assessed by visits to the workplaces, telephone calls or extrapolations. Conditional logistic regression analyses were done. Women working as hairdressers-beauticians$ sp+$ (O.R. 0,01 (0,00-0,34)) …  Lire la suite

This research has focused on the determination of natural populations in the fields, the effect of different inoculum densities on lettuce growth and a study of the association of this fungus with two nematodes (Pratylenchus penetrans Cobb and Meliodogyne hapla Chitwood). Under conditions of artificial infestation of soil the results were satisfactory, but in trials with naturally infested soil the fungus could not be detected. The effect of different inoculum densities was measured at different stages of growth, and only in those plants inoculated 2 weeks after seeding were differences significant and consistent. Some evidence of the detrimental effect of …  Lire la suite

Two studies are presented which investigated the relationship between oral contraceptives (o.c.s) and premenstrual changes in mood and physical state. The retrospective pilot study examined possible differences in symptom-reporting between groups of pill-users and non-users. Women using o.c.s had lower severity scores on a number of physical and mood-related symptoms compared to non-users. In the prospective study, eighty-two women with complaints of moderate to severe premenstrual symptoms were recruited for a double-blind, controlled trial of a triphasic o.c. Subjects made daily ratings of symptoms for one to two baseline cycles and were then randomly assigned to receive either placebo or …  Lire la suite

The purpose of this study was to investigate the effect of three different vocal timbres on uncertain singers' ability to match and discriminate pitches. Fifty-six children between six and eight year old were randomly assigned to one of four groups. In the Own Voices group, subjects were training in pitch matching using subjects' own voices. They trained in pitch discrimination using a model child voice as stimuli. In the Model Child group, subjects were training in pitch matching and pitch discrimination using a model child voice of the same sex and age as that of the subject. Subjects in the …  Lire la suite

Airborne magnetic field data exhibit downward continued power spectra of the form $1/f sp beta$ (where f is the spatial frequency and $ beta$ is a non-negative real number). This form of spectrum is observed for magnetic data recorded over a range of sampling scales from various areas of the Canadian Shield. Two scaling regimes have been discovered. The first has a $ beta$ value near 3 for wavelengths $ sbsp{ sim}{$25 km. These results suggest a "variable fractal" description of the distribution of near-surface magnetic sources. From a data modelling viewpoint, the magnetic measurements are derived from a linear …  Lire la suite

Tensile testing was carried out on five microalloyed steels in order to investigate the hot ductility behaviour between 800 and 1300$ sp circ$C, and between 1400$ sp circ$C and the solidus temperature. The influence of an increase of the carbon content up to the peritectic composition ($ approx$0.14 wt%) in Nb-Ti-Al bearing steels, and the effect of microalloying additions (Al, Al-Nb-Ti and, Al-Nb-Ti-V-Cr) were examined. Above 1400$ sp circ$C, intergranular embrittlement occurs by incipient melting at the grain boundary at temperatures between 0 and 30$ sp circ$C below the solidus. The increase in the carbon content from 0.7 to 0.14 …  Lire la suite

Let M be a k-dimensional manifold in $R sp{n}$. Using a new idea, we extend the known result of Y. Domar on the weak spectral synthesis property of M when k = n $-$ 1 by reducing the smoothness assumption upon M. For the case k $ leq$ n $-$ 2, the property is only proved for the curve in $R sp3$. We discuss the situation when M is a 2-dimensional quadratic manifold in $R sp4$ and the same result as in the ($n-1$)-dimensional case is proved. The interesting point of our method is its application to solving the uniqueness …  Lire la suite

The exploration of space started a long time ago with the inception of civil aviation. This mode of transport very soon became a matter of great interest to the military. Today our strategists are concerned about the outer space and the limits of our universe. We do not have an airforce anymore; we have an aerospace force. The first part of this thesis is a study of the air law applicable to the military operations of our pilots. The study begins with an introduction in the world of the international public law and then moves on to the laws of …  Lire la suite

Order-disorder phase transitions in solid cyclopentene, cyclohexene, tetramethylene sulfoxide, pentamethylene sulfide, cycloheptane, cycloheptene, 1,3-cycloheptadiene and 1,3,5-cycloheptatriene, were studied by various combinations of differential scanning calorimetry, proton spin-lattice relaxation time measurements, and variable temperature infrared and Raman spectroscopy. Possible unit cell symmetries have been proposed for the low temperature phases of several of these compounds, based on splitting observed in the vibrational spectra. The high temperature phases of cyclopentene, cyclohexene and 1,3-cycloheptadiene, for which the flexibility of the ring is reduced relative to the saturated analogues due to the presence of one or more double bonds, were found to be characterized …  Lire la suite

This study examines German-Soviet military relations between 1917 and 1922 and demonstrates the involvement of the Reichswehr in the Treaty of Rapallo. Since early 1919, the Reichswehr cultivated entente with the Soviet Union in opposition to the German government and in violation of the Treaty of Versailles, both to regain its military preeminence and to recapture Germany's power-political position in Europe. The Reichswehr attempted to draw German industry into relations with the Soviet state in order to secure the manufacture of military machinery and support troop training. By 1922, the foundation for collaboration between German industry, the Reichswehr and the …  Lire la suite

The current excitement surrounding string theory prompted us to tackle the problem of black hole radiation. Claims have been made concerning a possible 'stringy mechanism' that would avoid the singularity problem by giving a divergent energy-dissipation rate. As a check on such arguments, the Casimir energy of the string between two infinite parallel mirrors is computed using the closed, oriented bosonic string. Such a calculation is also a prerequisite to the understanding of the more interesting situation of string behaviour in the presence of accelerating boundaries. The formalism used here is the first-quantized Polyakov approach, which most simply translates to …  Lire la suite

The testing of printed circuit board (PCB) interconnects is a complex task that requires enormous amount of resources. With the increasing use of new technologies like surface mounting technology (SMT), testing PCB interconnects using the available techniques, like in-circuit testing and functional testing, is becoming very difficult. To make testing manageable, it must be considered earlier in the design process. This is known as 'design for testability' (DFT). A hierarchical DFT approach known as boundary scan architecture has recently become an increasingly attractive solution for PCB interconnect testing problems. This framework provides a scan path for electronic access to the …  Lire la suite

The activities of Neurospora endo-exonuclease, an enzyme which had been implicated in DNA recombination and repair, on double stranded DNAs are characterized further in this work. Endo-exonuclease is shown to have a very low bona fide endonuclease activity on covalently closed circular double stranded DNA. Much higher activity is seen with linear double stranded DNA. The enzyme is shown to bind the DNA at a terminus and track in the 5$ sp prime to 3 sp prime$ direction to make site-specific nicks and double strand breaks at or very near the hexanucleotide sequence pAGCACT or related sequences. The nuclease has …  Lire la suite

Whether in common law jurisdictions or in German civil law, the issue of pre-incorporation transactions has always been the subject of considerable controversy. Concerned with the promoters, third parties, the company and its shareholders, the law has found it difficult to balance these frequently conflicting interests without neglecting the need for clear and simple rules. Common law courts, sometimes excessively committed to legal principles, have even come up with absurd results. This survey looks at the various attempts made in order to reconcile legal principles and business requirements--legislative in most common law jurisdictions, juridical in Germany. It will critically examine …  Lire la suite

The ten year debate over the introduction of pay television in Canada is addressed using the concept of external signals to examine the interactions between the Canadian Radio-television and Telecommunications Commission (CRTC) and the players in the regulatory environment. A critique of the notions of "public interest" and of regulatory "capture" precedes the analysis. An historical overview establishes the key issues shaping the nature of the CRTC as a signal-sending and signal-receiving institution. The evidence demonstrates that the CRTC was not a passive receptor of external signals, but actively shaped and directed or deflected incoming signals according to its own …  Lire la suite

The case of Inuit broadcasting is fundamental for federal communications law and policy. The first part of this thesis explores Inuit attempts to establish a broadcasting presence in Canada. It concludes that Canadian northern aboriginal language broadcasters have positive rights to self-governance and self-survival over their cultural and linguistic institutions using modern communications technologies. In international law, a minority group communications model for such self-governance exists and could be effectively applied in Canada. […]  Lire la suite

In Lesch-Nyhan disease, concentrations of hypoxanthine are elevated especially in the brain and cerebrospinal fluid; dopamine and its metabolites are reduced in the caudate and putamen. Hence we investigated the possibility that hypoxanthine has direct effects on dopamine neurons. Hypoxanthine, adenine or allopurinol was delivered unilaterally into the rat brain. Behavioural effects were monitored by apomorphine-induced rotation; ipsilateral turning was time and dose-dependent. Turning was competitively blocked by a non-specific DA antagonist, suggesting that dopamine neurons were altered. In hypoxanthine treated animals, a D1 antagonist specifically blocked rotation; catalepsy occurred after caffeine administration. After two or three weeks treatment all …  Lire la suite

The purpose of this study was to explore the relationship between divergent thinking and Schmidt's schema theory of motor learning in a population of first year University physical education students. Problem solving teaching methodology was used as the intervention program in this study and the main sources of data were the Torrance Tests of Creative Thinking and tests of Schmidt's schema theory designed by the researcher. Descriptive data were used to explain the intervention program. A mixed model analysis of variance was used to compare the pre-test and post-test performance on Torrance Tests of Creative Thinking (TTCT), and the Pearson …  Lire la suite

The Radio Canada International news and current affairs program "Canadian Journal" is used as a case study to develop an adequate theory of news work. A theory of news structuration is proposed which seeks to overcome the dichotomy between agency and structure in news sociology. News is conceived as a social production which constitutes, and is constituted by, its institutional conditions.  Lire la suite

In early nineteenth century Lower Canada, a direct relationship existed between the colony's laws of employment and the nature of its economy. As the artisanal and manufacturing centre of British North America, Montreal, in the first third of the century, had a pre-industrial economy. Its legal treatment of the master/servant relationship was established and directed by masters, and drew heavily upon the spirit of the pre-industrial traditions of English common law, emphasizing the criminal liability of servants failing to respect contractual obligations. Montreal's domestic servants, who were drawn from the poor and popular classes, and included mostly women and minors, …  Lire la suite

Partant du constat de l'importance du sujet pour le peintre futuriste a une epoque ou les avant-gardes europeennes tendent a l'abstraction, la presente etude demontre que la ville fut un theme capital dans l'elaboration de l'esthetique futuriste. En effet, les peintres italiens ne cherchaient pas tant a depeindre l'apparence, l'aspect visible de la ville qu'a apprehender de facon conceptuelle les idees-forces qui en emanaient. A travers l'entite "ville", ils revelerent les concepts inherents au monde moderne et en etablirent les equivalents plastiques. Ainsi, c'est a travers le sujet de la ville que s'expriment les idees-forces les plus originales du mouvement, …  Lire la suite