McGill University Thèses et mémoires publiés en 1997

This study explores the effects of ethno-religious tensions on the dynamics of fraternalism in nineteenth-century Montreal. With the Irish "national society" as its focus, it relates the internal politics of the Saint Patrick's Society of Montreal to broader narratives of the cultural, intellectual and institutional evolution of civil society in Lower Canada. Beginning with an overview of sources and a discussion of early Irish migration, it proceeds to explore the effects of emerging social and political patterns and ethno-religious identities on a middle-class fraternal project from the early nineteenth-century to the dissolution of the Saint Patrick's Society in 1856.  Lire la suite

The possible roles of the anti-apoptotic protein, Bcl-2, and pro-apoptotic Fas receptor-ligand interactions in cell death decisions during the development of B lymphocytes in mouse bone marrow and their maturation in the spleen have been evaluated in gene-modified and mutant mice. In Emu-bcl-2 transgenic mice, the population dynamics and tissue organisation of phenotypically defined precursor B cells, have been evaluated by immunofluorescence labeling, mitotic arrest, BrdU uptake, flow cytometry and in vivo radioimmunolabeling combined with light and electron microscope radioautography. In bone marrow of Emu-bcl-2 mice, the number and production rate of proliferating precursor B cells were increased. Immature B …  Lire la suite

A detailed study of the evaporation of levitated copper droplets in presence of homogeneous condensation over a range of temperatures, from 1800 K to 2200 K, pressures, from 10 kPa to 101 kPa and inert gas flowrates, from 0.07 * 10-4 m3 s-1 to 7.40 * 10 -4 m3 s-1, was undertaken. Several calibration techniques to measure the temperature of a 5 mm copper droplet using a two-color pyrometer are described. The levitated droplets required a short time to reach steady temperature with the result that the average measured loss of copper by evaporation was less than steady state evaporation …  Lire la suite

Mechanization signaled the end of the cavalry but the renaissance of heavy cavalry doctrine. The tank heralded the return of breakthrough operations and maneuver warfare. Initially, the western cavalries refused doctrinal revision and chose instead to fight bitter rear guard actions against Fullerist zealots. The Canadian Cavalry, prompted by Blitzkrieg's triumphs, effortlessly evolved into a tank force---virtually overnight. Canadian doctrine, however, was ersatz. Denied its own vast training areas, the RCAC was sandwiched into southern England and saddled with British warfighting techniques developed in the Western Desert. In Normandy, Canadian operational art was driven by Generals Simonds and Crerar, both …  Lire la suite

The clogging of fine-porosity geotextiles by soil particles is considered to be a problem in applications of these fabrics to filtering of municipal and industrial effluents. However, the clogging phenomenon can be an advantage for certain purposes, such as the creation of near-watertight membranes for sealing manure holding tanks. The conceived advantages of non-woven needle-punctured geotextiles are that they are less expensive due to lower material quantity, they are more resistant to tensile stresses compared to impermeable plastics and concrete, and they are easily installed. This thesis describes experimental work on the permeability and clogging characteristics of a Non-woven Polyester …  Lire la suite

Subirrigation systems are generally used in humid areas to provide suitable moisture conditions for plant growth. These systems can also be used to reduce pesticide loadings from agricultural lands, since they tend to keep the discharging waters within farm boundaries for extended periods of time. This allows for greater pesticide microbial and chemical degradation. A three-year field lysimeter study was initiated to investigate the role of subirrigation systems in reducing the risk of water pollution from the three most commonly used herbicides in Quebec, namely atrazine (2-chloro-4[ethylamino]-6[isopropylamino]-1,3,5-triazine), metribuzin (4-am ino-6(1,1-di meth yl eth yl)-3-(meth yl thio)-1,2,4-tria zin-5(4H)-one), and meto lach …  Lire la suite

Canadian intellectual Marshall McLuhan (1911--1980) left a controversial legacy. This dissertation addresses the four chief paradoxes that his work poses for contemporary commentators: the core meaning of his texts; the tradition in which his contribution now seems most intelligible; the divergent response to his work; and the enduring yet fragmentary impact of his contribution to popular and academic life. Taking a rhetoric of inquiry approach, modified by Gerald Holton's writing in the history of science, this reappraisal argues for McLuhan's significance as a theorist of communications as techno-cultural transformation or "mediamorphosis"; for his seminal role within the Toronto School of …  Lire la suite

31P NMR spectroscopy was further developed for the structural elucidation of lignin by undertaking a series of systematic studies. More specifically, a detailed model compound investigation showed that 2-chloro-4,4,5,5-tetramethyl-1,3,2-dioxaphospholane is an additional phosphitylation reagent which may provide further quantitative structural information about lignin. Correlation analysis using the Hammet principles revealed that the 31P chemical shifts of lignin- related phenolic hydroxyls with various substitution patterns strongly depend on the nature of the substitution. Such structure-chemical shift correlations led, for the first time, the development of a set of empirical parameters that permits the accurate prediction of 31P chemical shifts of lignin-related …  Lire la suite

Mucciardi, Frank (Supervisor)  Lire la suite

In a group of predominantly light smokers (N = 10), EEG was recorded before and after cigarette smoking both during rest, and while engaged by two cognitive/perceptual tasks (i) the video game Tetris, and (ii) a computerized reverse mirror drawing task. Increases in beta2 power occurred 0-2 minutes after smoking, which were significant in half the subjects. Significant decreases in peak alpha power and an increase of 0.7 Hz in peak alpha frequency existed 1-2 minutes after smoking. Alpha frequency and power were examined again 11 minutes post-smoking and were found to still be altered, although this did not reach …  Lire la suite

This work includes several studies exploring functional specialization of human primary and anterior secondary auditory cortex (AC) in the two hemispheres. It was hypothesized that the left hemisphere prepotency for linguistic processing is based, in part, on specialized mechanisms within this hemisphere for the processing of acoustic transients relevant to speech. Evidence supporting this idea was obtained in a positron emission tomography study (PET). Since nonlinguistic stimuli were used, the observed left-hemispheric activation cannot be specific to the speech system, but must reflect a more general processing mechanism. A reanalysis of data from six auditory PET studies revealed that the …  Lire la suite

Starting with Jerome McGann's landmark 1979 essay "Keats and the Historical Method in Literary Criticism," the recent sixteen-plus years of Keats criticism brims to overflowing with the dominance of New Historicism and its archaeological recovery of the political, historical Keats against the previous preeminence of a formalist, aesthetic Keats. The grip of New Historicism now holds tightly enough, perhaps, to the point where it suffers from a lack of attention to formalist, aesthetic, stylistic differentials and peculiarities. A critical position, then, that addresses this lack of attention looks to be an assessment of the relationships between New Historicism and formalism: …  Lire la suite

The chondroitin sulphate epitope 846 of aggrecan is abundant in foetal cartilage, barely detectable in normal adult cartilage, but reappears in the cartilage and body fluids of arthritic patients. This epitope has been proposed to be a marker of aggrecan synthesis during new cartilage formation and repair. The purpose of the present studies was to investigate, in vitro, whether the epitope was truly reflective of aggrecan synthesis, and to understand its role in the cartilage repair process. Foetal bovine chondrocyte cultures were established to study aggrecan synthesis in order to investigate whether the epitope 846 was present on these molecules. …  Lire la suite

Requirements of electronic systems are increasing, as the applications for these systems become more complex and require more bandwidth. Optical interconnection can help satisfy these system requirements. In order for an optical interconnect to be successful, system design must satisfy new demands on the packaging of the optically interconnected devices, different from those encountered in packaging electronic interconnects. This thesis addresses the issues faced in designing the packaging for a two-dimensional array of surface active optoelectronic devices, within the framework of a free-space optically interconnected backplane. Two demonstrator systems' packaging are presented, as well as a general discussion of the …  Lire la suite

Mycorrhizal fungi are a major component of agricultural systems and play a key role in plant nutrition. Little is known about the effects of tillage practices and manuring on arbuscular mycorrhizal fungi (AMF). The purpose of this study was to evaluate the effect of soil disturbance on winter survival, development and distribution of AMF in soil and on plant nutrient uptake and productivity. This research was conducted in long-term corn plots in two soils and under controlled conditions. A growth chamber study with field soil demonstrated that most of the fungal hyphae with mycorrhizal plants were mycorrhizal rather than saprophytic. …  Lire la suite

This report presents the results of a study on the benefit of chloride ion testing in the prediction of soil corrosivity, which is determined using the method of linear polarization. Existing industry standards such as AWWA C105 and PACE 82-3 are currently being used to evaluate the corrosivity of soils. These standards consist of various tests, whose results permit the calculation of a corrosivity index. The following tests are suggested: pH, oxidation-reduction potential, sulfide ion content, resistivity, drainage ability, soil type, and moisture content. Up to this point, no standards have incorporated chloride ion testing into their testing procedure, even …  Lire la suite

The effect of salinity on phosphorus (P) absorption kinetics by 'Russet Burbank' cv. potato propagated by tissue culture technique was studied in the laboratory. Nine clones of the cultivar were evaluated for their salt tolerance at the vegetative stage by using in vitro culture. Four concentrations of NaCl (0, 40, 80, and 120 mM) were used in the experiments. The first experiment was carried out to study the effect of salinity on P absorption by using radiophosphorus ($ sp{32}$P) as a marker. P absorption showed a quadratic relationship with time. In general, there was a significant reduction in P absorption …  Lire la suite

Several collections of partial semigroup models for the Lambek Calculus are described and results regarding soundness and completeness of the Lambek Calculus with respect to those collections of models are presented.  Lire la suite

The human wildtype p53 tumor suppressor gene contains a polymorphism at amino acid residue 72 which results in either an arginine (p53 Arg-72) or proline (p53 Pro-72) at this codon. In the present study I have examined this polymorphism at the molecular level to determine whether differences exist in the biochemical functions of these two p53 variants. No differences were observed in their sequence-specific DNA binding abilities, nor in their ability to be targeted by HPV-18 E6 oncoprotein for degradation by ubiquitination in vitro. However, differences were observed in the ability of these two variants to function as transcriptional activators: …  Lire la suite

This thesis deals with the political philosophy of al-Ghazzali from an analytical point of view. It focuses its examination on his theory regarding the imamate and sultanate. This examination is based on four of his works, namely, Fad&dotbelow;a'ih&dotbelow; al-Bat&dotbelow;iniyah wa-fad&dotbelow;a'il al-Mustaz&dotbelow;hiriyah, al-Iqtis&dotbelow;ad fi'l-i'tiqad, Ih&dotbelow;ya' 'ulum al-din and Nas&dotbelow;ih&dotbelow;at al-muluk . It begins with an account of past scholarship on al-Ghazzali's political thought. Until recently scholars have focused on al-Ghazzali's theories without giving due consideration to the circumstances that led him to develop them. This thesis shows how they were shaped by his encounter with the 'Abbasid court and the Seljuq …  Lire la suite

A water-methanol solution of glycine and scD-glucose was refluxed for seven hr. The solvent was evaporated under vacuum at room temperature and the residue was dialyzed against distilled water. After dialysis, the solvent was evaporated under vacuum at room temperature. The non-dialyzable fraction was further fractionated by gel filtration. The process yielded three polymeric materials (10,000 $<$ M $<$ 20,000) whose purity was verified by HPLC. The isolated polymers were further analyzed by UV-VIS and FTIR spectroscopy and by pyrolysis/GC/MS. Elemental analysis indicated that polymer A has the following empirical formula $ rm C sb6H sb{11}N sb1O sb4$ and polymers …  Lire la suite

A dendrochronological and dendrochemical study was undertaken near the village of Kuujjuaq, northern Quebec. Changes in climate, radial growth and mineral nutrition of trees, as well as the contamination in Mn and Zn of tamarack and black spruce forests of the region during the last forty years were investigated. A growth model based on climatic variables was produced for each species. The regional climate didn't show any steady trend of increase in temperature and precipitation with time. However, the 1953-1964 decade was the warmest one and the 1964-1973 decade received the most precipitation. Radial growth of both species have probably …  Lire la suite

In this work, the dependence of the vacuum arc spot velocity on physical and electrical properties of different graphite cathode materials is investigated in the presence of a variable magnetic field. A pulsed arc system is used to perform preliminary experiments on the arc mobility for the different types of graphite for the selection of proper material morphology and the design of a continuous vacuum arc system. The characteristics of arc mobility, erosion rate, and carbon ion flux emitted from the continuous carbon source are then evaluated in view of particle-free diamond-like protective coatings. Results show that the arc spot …  Lire la suite

The effect of pulp potential on the recovery of copper, lead, zinc and iron from the ore of Kidd Creek Mines (Timmins, Ontario) was examined. Air and nitrogen as flotation gases were compared for their effect on the metallurgical response (recovery and the separation efficiency of Cu/Zn and Cu/Fe). The extraction of metal cations from the mineral surface in-situ by EDTA at varying pulp potentials and with various reagent schemes was performed, and the differences in extraction from concentrates and tailings was examined. The effect of aeration on the extraction of cations Cu, Pb, Zn and Fe was analysed as …  Lire la suite

Global Navigation Satellite Systems (GNSS) are a key component of the ICAO Communication Navigation Surveillance---Air Traffic Management (CNS/ATM) system. The fact that GPS and GLONASS, currently the only systems that partially meet the requirements for ICAO's GNSS, are military systems owned, operated and controlled by the US and the Russian Federation raises several institutional and legal issues for civil aviation. This thesis will present the institutional and legal issues of the GNSS which have been recently discussed in the framework of ICAO. The certification issue to ensure the safety of civil aviation will be considered. The possibility of the legal …  Lire la suite

Noumoff, Sam (Supervisor)  Lire la suite

The Italian literature which came to life in the Eighties broke with the tradition of the preceding period during which fiction was but a fertile ground for social criticism. Furthermore, the new literary scene came to be dominated mainly by unknown young writers, who had come of age in a decisively new and modern social setting in Italy. This thesis aims at presenting the writers that make up most of the "Giovane Narrativa" of the Eighties. It also presents the main aspects of the social and economic development in Italy after the war and their relevance to this generation of …  Lire la suite

Filters constitute an essential tool for manipulating the spectral content of a signal. While there is a plethora of filtering tools, both in the hardware and software domain, the majority of them are geared towards engineers and scientists, rather than sound designers and electroacoustic composers. The "common-practice" approach is to consider filters as post-production tools. This can be restrictive if filters are to be used as artistic tools, dynamically involved in the shaping of the sound. This thesis was written with this approach in mind its aim is (a) to provide a survey of the various digital recursive filters, enabling …  Lire la suite

Sport is a particularly ideologically-charged terrain within contemporary gender relations because it is centered on the body. The body is our most 'natural' marker of sexual identity, and thus, in our socio-cultural imaginations, of gender identity. Accordingly, gendered boundaries in sport have traditionally constructed and promoted an ideology of 'natural' gender differences, and sport is a site--a microcosm--where traditional beliefs and assumptions about female weakness and male strength are promoted and maintained. Sport is understood to be both reflective as well as indicative of the female/male dichotomy which exists in the more general social mythology. Gendered boundaries are constructed, and …  Lire la suite

Despite discrimination in mainstream Canadian society, local Muslim communities are a significant resource for immigrants. Recruited by friendship and kin networks, some families chose to educate their children in private full-time Muslim schools which provide academic/economic credentials and social support. Through participant observation and semi-structured interviews, this research depicts a Muslim school in Montreal which both reflects Quebec society and nurtures minority ethnic/religious identity. For many parents, Arabic language classes, academic standards, and behavioral norms were as important as the school's religious affiliation. Rejecting the hypothesis that emphasizing religious and cultural identities distanced children from mainstream society, some felt that …  Lire la suite

Mammalian Cut proteins appear to function as transcriptional repressors that play a role in determining cell type specificity. Recent evidence suggests that cut genes are tumour suppressor genes. This hypothesis was further examined by using functional assays to evaluate the abilities of human Cut to: (a) suppress oncogene-mediated cell transformation, and (b) interact with the SV40 Large T (LT) antigen. The results indicate that: (a) there was a decrease in the number of transformed colonies and foci when rat embryo fibroblasts (REFs) were transfected with ras/c-myc or ras/E1A and cut; (b) the homeodomain region of Cut interacted with SV40 LT …  Lire la suite

Bioavailability of trace metals in urban contaminated soils was investigated to relate chemical extraction efficiencies with biological effects. Results from a Collembola reproduction bioassay showed minimal toxicity suggesting limited bioavailability. Chemical extractions were carried out on these urban soils. The sodium acetate extraction was the best predictor of the biological effects of Cd while the biological effects of Zn were best explained by a water extraction. An earthworm uptake bioassay was done to quantify the bioavailable fractions. Cadmium, Cu, Pb and Zn accumulated in Lumbricus terrestris L. The sodium acetate extraction was the best predictor of Cd uptake while calcium …  Lire la suite

Thylakoid organization and the distribution of photosystem (PS) I and II proteins in the green alga Coleochaete scutata were analyzed by electron microscopy. Thylakoids were observed to associate in varied conformations. Extended bands of thylakoids were present, as in other algae, but numerous grana, characteristic of higher plants, were also detected. Immunolabelling experiments were conducted with two heterologous antisera raised against PS proteins in the cyanobacterium Synechococcus elongatus: one antiserurn against the 60 and 62 kDa PSI reaction centre proteins, the other against the 47 kDa PSII core antenna protein. PSI was 2.6 times more concentrated in the nonappressed membranes …  Lire la suite

The purpose of this thesis is: (1) to review the airport development and transportation policy of the United States (U.S.); (2) to provide an overview of the U.S. constitutional doctrines evolved under the Supremacy and Commerce Clauses, and their respective applications in the case law; (3) to review the regime of federal regulation of airport noise; (4) to examine the State Legislature's emphasis on "aeronautical progress" in the New Jersey State Aviation Act of 1938, as amended; (5) to examine the role of the State Aviation Act in zoning on and around airport land; and (6) to provide a detailed, …  Lire la suite

Pyrolysis/GC/MS was utilized as an integrated reaction, separation and identification system to study the thermal degradation products of non-volatile Maillard flavor precursors. Model systems of scL-phenylalanine (aromatic amino acid), glycine and scL-alanine (aliphatic amino acids), scL-serine ($ beta$-hydroxy amino acids) and scL-methionine (sulphur containing amino acid) were investigated. Quartz tube pyrolysis of scD-glucose/amino acid or dicarbonyl/amino acid mixtures shortened the analysis time (from hours to minutes) and eliminated the need for extraction since the volatiles generated from the precursors are directly transferred into the GC column. Phenylalanine Amadori product and different model systems containing phenylalanine and different reducing sugars were …  Lire la suite

Computational Fluid Dynamics (CFD) is emerging as an integral part of engineering design and analysis. Traditionally, idealizations have been made to categorize flows as being either incompressible or compressible, with their respective numerical treatments being completely different. Incompressible flow solvers are completely incapable of capturing compressible flow phenomena, while compressible flow solvers are very inefficient in the limit of low compressibility. For situations in which there are regions of incompressible and compressible flows, or when there is no a priori knowledge of the level of compressibility, a general numerical treatment is no longer obvious. The method proposed in this thesis …  Lire la suite

One major task facing the geoenvironmental engineering today is the development of methods to assess the long term changes, release and transport of contaminants from waste disposal sites, considering the hydrochemical interaction of the contaminants with the clay barrier. Modelling of the leaching processes, which take place in a landfill, is an invaluable tool as it is often not possible to conduct experiments over sufficiently long timescales to observe the long term leaching behaviour of wastes. In this study the multi-component transport of heavy metals into a clay barrier has been investigated experimentally and theoretically by coupled solute transport and …  Lire la suite

Langleben, David (Supervisor)  Lire la suite

This thesis surveys the religious thought and political activities of K. H. (Kyai Haji) Hasyim Asy'ari (1871-1947), founder of both the Pesantren Tebuireng and the Nahdlatul Ulama. Given the extent of his legacy, it will study his life, educational background and pesantren milieu in order to gain an understanding of his career and the events that inspired him. A prolific writer, K. H. Hasyim Asy'ari produced works on theology, sufism, politics and Islamic law. Many of these works will be discussed. His theology was standard Sunni, while his mystical practice and thinking may best be described as sufi/ orthodox. He …  Lire la suite

McGill University is near completion on a five year Major Project in Photonic Devices and Systems funded by the Canadian Institute for Telecommunication Research (CITR). The objective is to build and demonstrate a representative subset of an electro-optical "Intelligent Optical Backplane" system capable of handling terabit data rates. This thesis describes the construction and demonstration of a prototyping printed circuit board (PCB) known as the ATMCard. The goal of the ATMCard is two-fold. The first is to develop an electronic PCB supporting ATM switching which can be connected to the 1998 CITR optical backplane demonstrator with minimal adjustments. The second …  Lire la suite

The buffer gas cooling process and the properties of the cooled beam in a novel rf quadrupole ion beam guide with axial field was studied. The operation principle of the axial field quadrupole ion beam guide is similar to the quadrupole mass filter operating in AC only mode but the rods were segmented and differential DC biases were applied to produce the axial field. It was operated in buffer gas. A Monte Carlo simulation was developed and the simulation results were compared with the experimental results. The beam distribution in a thermal equilibrium was assumed as the thermal equilibrium distribution …  Lire la suite

Commutation signaling is a bandwidth expanding modulation scheme that is robust to multipath induced intersymbol interference. Surface Acoustic Wave (SAW) technology is very suitable for implementing high-speed commutation signaling modems. A SAW-based commutation signaling modem for broadband indoor wireless communication is described. The differential coherent detector is a key element since it performs IF matched filtering and differentially coherent demodulation of the received signal. A commutation signaling differential coherent detector has been implemented using SAW and analog silicon technologies. The bit rate is 40 Mb/s, the chip rate is 200 Mc/s and the operating frequency (IF frequency) is 1 GHz. …  Lire la suite

Neurohypophysial hormone secretion from the nerve terminals of magnocellular neurosecretory cells (MNCs) is optimized by increases in firing frequency and the adoption of specific bursting patterns in the cell soma. The mechanisms that modulate these spike discharge properties of MNCs were hypothesised to involve Ca2+-dependent K+ currents, which have been documented to participate in firing frequency and patterns in other central neuronal populations. Electrophysiological experiments were used to characterize the current underlying the Ca2+-dependent AHP in MNCs, the activity-dependent requirements for its activation and its functional role in modulating MNC firing. IAHP is tonically activated in cells firing at frequencies …  Lire la suite

How is it that some potentially strategic issues find themselves on a Rim's strategic agenda, while others do not? Why is a top manager more attentive to some aspects of his firm's strategic situation than to others? What shapes his interpretation of his firm's strategic reality? How does strategic issue diagnosis (SID) actually take place within a top management team? These are the types of questions that this thesis addresses. It contends that the way strategy formation in general and SID in particular have so far been studied in top management teams---through essentially cognitive lenses---has been inadequate, largely because these …  Lire la suite

Doehring, Peter (Supervisor)  Lire la suite

An experimental laboratory study was undertaken to investigate the convective airflow which develops in compost masses and the effect of passive and active aeration on nitrogen (N) and carbon (C) losses of compost at three different levels of dry matter (d.m) with four different C sources (pine shavings, grass hay, oat straw and wheat straw). Each bulking agent was individually mixed with swine slurry and composted at 40, 32 and 28% d.m. Duplicate mixtures were aerated for 21 days (14 days for one of the pine shavings trials) both in active and passive conditions in 100L composters and their temperature …  Lire la suite

This thesis examines the construction practices in the traditional domestic architecture of Kerala in India. In doing so, it identifies two vital aspects of the architecture, namely the Vedic planning principles of the Vasthushasthra and the indigenous craft practices. The thesis pays tribute to both: the theories of Vasthushasthra in the construction of houses are examined in detail; the craft practices are documented and analyzed through a field study of 24 houses in Kerala selected across the caste, class and religious structures of the society. The thesis arrives at the proposition that the construction practices in the domestic architecture of …  Lire la suite

Current evidence indicates there exists two populations of neuronal nicotinic acetylcholine receptors, the $ alpha$-bungarotoxin ($ alpha$-BGT) sensitive and $ alpha$-BGT insensitive receptors. While the latter are thought to be involved in neurotransmission, the physiological significance of the former are not fully understood. However, evidence suggests that the toxin sensitive receptors may mediate trophic functions. The present studies were carried out to develop and validate novel and unique model systems for studying the structure, function and regulation of the nicotinic $ alpha$-BGT receptor. To this end, two such systems are presented here. First, the immortalized rat hippocampal H19-7 cell line …  Lire la suite

The aim of this thesis is to examine certain aspects of the thought of the orator Demosthenes, which relate to foreign affairs. Starting from the Demosthenic corpus, the investigation goes beyond the question at issue in any particular speech in order to note some of the permanent principles which governed the politics of the orator and determined his choices. It deals particularly with Demosthenes' position on certain ideas, such as interest, power, alliances, reputation and law, his choice of war or of peace, and the importance which the orator gives to chance and opportunity. After a contextual examination of these …  Lire la suite

Human nonspecific cross-reacting antigen (NCA), a close relative of the tumour marker human carcinoembryonic antigen (CEA), is also an in vitro homotypic intercellular adhesion molecule capable of inhibiting differentiation when expressed ectopically in myoblasts. Moreover, NCA appears to be overexpressed at the transcriptional level to a greater extent and more frequently in colorectal carcinomas than CEA. This study examines the transcriptional control mechanisms responsible for orchestrating NCA expression. The region within 283 bp upstream of the translational start site of the NCA gene was found to be capable of directing high levels of expression in functional promoter assays. Footprinting experiments …  Lire la suite