McGill University Thèses et mémoires publiés en 1990

This study explored the teaching of agriculture in Kenya's primary schools. It sought in particular to determine how the principles of "modern" agriculture may be taught effectively. Previous studies on education and agricultural productivity have ignored the mechanisms through which schooling affects the acquisition of agricultural knowledge and skills. This study attempted to bridge this gap. To do so field work was carried out in four schools and their catchment areas in Kiambu and Kwale districts of Kenya. The data stemmed from field notes, tape recorded lesson transcripts, interviews and questionnaires as well as an exhaustive review of prior studies …  Lire la suite

Islam was drastically altered in Iran as a result of the 1978/79 Revolution. This thesis looks at the political aspects of contemporary Imami Shi'ism by comparing the ideas of three leading mujtahids of the day: Ayatullah Shari 'atmadari, Ayatullah Khumayni, and Ayatullah Taliqani. This study points out the wide divergences of ideas present within the religious class, ranging in the political spectrum, from conservative to radical. A comparison of these three figures highlights the differences between "Traditionalist" Islam, as put forth by Shari 'atmadari, and "Fundamentalist" Islam, as proposed by Khumayni and Taliqani. Further differences within the fundamentalist "camp" are …  Lire la suite

This investigation was carried out in order to determine the specificity of a panel of monoclonal antibodies previously generated against murine pregnancy-associated splenic natural suppressor cells and to characterize the cell surface target molecule(s) on cells that are recognized by these antibodies. The monoclonal antibody from clone 2C1.1 was purified on anti-rat Ig affinity column and used to partially characterize the antigenic determinant recognized by it. A 50 KDa target molecule was detected on pregnancy spleen cells enriched for Natural Suppressor activity but not on similar cells from the virgin animals. Experiments employing a cellular ELISA technique demonstrated that the …  Lire la suite

The purpose of this study was to examine the role of the secondary school principal in anglophone Quebec. A sample of eighteen experienced principals were interviewed in-depth about their role expectations, sources of role conflict, and their sense of ambiguity. Role ambiguity appeared to be non-existent in the principalship. Expectations and conflicts were identified with regard to students, teachers, parents, community members, and principal's superiors. The principalship was clearly more a managerial than leadership role. Principals were responders to a series of problems and issues. They orchestrated responses. Instructional leadership was not a part of their role.  Lire la suite

The effects of taurine deficiency on aspects of retinal cGMP metabolism were examined. Rats were made taurine deficient by the administration of 1% GES. The activities of the key enzymes of cGMP metabolism, phosphodiesterase and guanylate cyclase, were indirectly determined by the response of retinas to light and to low calcium. Dark-adapted retinas of rats treated with GES for 4 and 8 weeks exhibited significantly smaller decreases in cGMP in response to light exposure as compared to control retinas. Retinas from 4 and 8 week GES-treated rats also exhibited smaller increases in cGMP when they were exposed to 0.1nM calcium. …  Lire la suite

Sexual 'arousal' in Helix aspersa can be divided into 2 components, sexual proclivity (the tendency of a snail to respond to conspecific contact with courtship) and sexual arousal (the intensity with which the snail courts). Sexual proclivity and sexual arousal have different effects on feeding and locomotion and are differentially affected by sexual isolation, daily conspecific contact, and by a courtship pheromone found in the digitiform gland mucus. Therefore sexual arousal and sexual proclivity are probably mediated by 2 separate physiological mechanisms. Behavioural state, or the animal's general level of activity, correlates positively with mating behaviour. However, although a central …  Lire la suite

This thesis focusses on the seizure-promoting effects of second messengers, in particular calcium and others activated by calcium in CA1 subfield of rat hippocampus in situ and in vitro. Interictal discharges were simulated in hippocampal slices using the low Ca$ sp{2+}$ model where synaptic transmission is blocked. The antiepileptic drug valproic acid (VPA), which is postulated to potentiate GABAergic responses, reduced the low Ca$ sp{2+}$ field bursts, thereby suggesting a non-synaptic mechanism of action of VPA. Extracellular and intracellular recordings from hippocampal neurones bathed in low Ca$ sp{2+}$ solution revealed that even though evoked transmitter release was blocked, small spontaneous …  Lire la suite

This study examined the interaction of religion and politics in Bangladesh in light of the hypothesis that the nature of the particular process of Islamization of the state of Bangladesh, leading to its present semi-Islamic status, has been a function of three independent variables: the specific nature of Islam in the society; the configuration of political interests; and the international environment. The study found that the semi-Islamic status of the state in Bangladesh achieved under military rule is a consequence more of the manipulation of Islam by the military for the sake of legitimacy and of the influence of the …  Lire la suite

The problem of fault diagnosis in digital circuits is composed of two sub-problems: Fault detection (identifying that a fault is present) and fault location (identifying the failure responsible for faulty behaviour). Tests using randomly or pseudo-randomly selected input stimuli have been suggested both as a means of reducing the costs associated with generating deterministic tests and as a means by which circuits could test themselves (built-in self-test). The majority of research into random testing has dealt only with its fault detection properties. Fault location has typically been treated as a dictionary search problem, or ignored altogether. This dissertation proposes a …  Lire la suite

Experiments were carried out in order to investigate the response of reinforced concrete bridge pier caps. The six specimens were tested in order to study the influence of the geometry of the pier caps, the amount and distribution of uniformly distributed reinforcement in the pier caps and the details of anchorage of the reinforcement. The experimental results were compared with predictions using plane sections analyses, simple strut and tie models, the PCI design method, more refined strut and tie models and non-linear finite element analyses using program FIELDS.  Lire la suite

This thesis focuses on transactional process involved in the construction and operation of the Kuskokwim River Salmon Management Working Group. This cooperative wildlife management mechanism gives Yup'ik commercial and subsistence fishermen and other users a direct role, with the Alaska Department of Fish and Game, in salmon management. Transactions involving participants' knowledge and values are described in three processes: (1) the establishment of a management body and its operating rules; (2) the mediation of power in decision-making; and, (3) fishery management which uses both "science" and "fishermen's knowledge." Results indicate that through cooperation in decision-making, data gathering, and other management …  Lire la suite

Precision of determining age in ringed seals (Phoca hispida) was examined by repeated readings of undecalcified cross sections and decalcified stained longitudinal sections of mandibular canines. There appeared to be geographical differences in repeatability although this could not be tested statistically. There was no difference in repeatability between cross and stained sections. The effect of precision on population parameters was examined. Smoothing procedures necessary to construct life tables and to do Leslie matrix calculations obscured any differences in ages between readings. Variance between readings was found to give inconsistent notions of sexual maturity. Imprecision caused little overall difference in growth …  Lire la suite

Two prospective investigations of periodicity of sexual behavior, well-being and testosterone (T) levels in women using and not using oral contraceptives (OCs) found no relationship between daily ratings of sexual desire and well-being across one pill and menstrual cycle. T, but not estradiol or progesterone, was positively correlated with sexual desire and sexual enjoyment in OC-users when T levels were below normal menstrual values. Other evidence suggested on association between post-ovulatory decreases in T and sexual desire in women. A bias to attend to sexual stimuli on a dichotic listening task was associated with sexual arousability in men. Moreover, task …  Lire la suite

This thesis presents the phenomenon of communal habitation--from a traditional scene to a contemporary vista--in terms of a historical progression. It exhibits a hypothesis that attempts to justify the reason behind the deterioration of identity, livability and of neighborliness in contemporary neighborhoods. Although this thesis, in accordance with some contemporary community planning theories, pronounces the relevancy and importance of physical as well as social planning, it articulates, in line with annals of contemporary urban history, their incompetency to constitute the virtues of a good living place. In other words, urbanization, according to this thesis, is neither a mere physical pattern …  Lire la suite

The present study aims to understand the subject matter of the Shajarat al-Kawn. In the two earlier studies of this text--both translations, the first in English and the second in French with extensive notes--the translators approach the text with specific preconceptions which influence the translations and analyses. In contrast, our approach is to focus on the persons, events and images within the text and thereby to reveal the salient issues and themes. In the analysis we are led to question the authorship of the text, specific details reveal that it may not be by Ibn 'Arabi In spite of this …  Lire la suite

The potential of granular zeolites as a heating medium for drying corn was evaluated in a batch type experimental dryer. At temperatures from 150-250$ sp circ$C and residence times of 3-8 minutes, synthetic zeolites (4A and 13X) removed 9-18 percentage points from the initial moisture of corn. These values were about double those of sand, the most commonly used particulate medium. Using an adiabatic dryer, the kinetics of moisture sorption in corn-zeolite mixtures was investigated. The heating medium in this part of the study was a natural zeolite (chabazite) and the corn was yellow dent type. Diffusivity values for corn …  Lire la suite

In this study a technique--that almost completely eliminates shrinkage microporosity--has been developed which uses small additions of strontium together with risers and chills to produce porosity-free AZ91C (Mg/Al/Zn) magnesium casting alloy castings. With the optimum level of Sr addition (0.01% to 0.02% Sr), shrinkage microporosity was removed from the casting and concentrated in the riser. The castings were already grain-refined by carbon inoculation. The effect of strontium is explained by a further reduction in the grain size of the castings from 250$ mu$m to 120$ mu$m. This effect produces a much denser casting due to increased mass feeding. In addition, …  Lire la suite

The travelling salesman problem is one of the NP-complete problems. It has been under consideration in computer science for at least forty years. Solving this hard problem using search methods can be accomplished by choosing: a starting point, a solution generation scheme and a termination rule. When the termination rule is such that search stops if and only if the tour is optimal, we call the method "exact". When the termination rule is such that the search stops but not necessarily with an optimal tour, we call the method "approximate". This thesis looks closely at one of the approximate methods, …  Lire la suite

The virus-inducible Type I interferon (IFN) genes serve as relevant models to examine the nature of cis-acting sequences and trans-acting protein factors involved in transcription control. The alpha and beta interferon genes are activated differentially depending on the nature of the inducer and the specific cellular background. A transient expression system was developed to analyze the activation of the interferon promoters in a homologous human cellular background. In epithelial cells, the IFN-$ beta$ but not the IFN-$ alpha$1 promoter was virus responsive with induction kinetics similar to that of the endogenous IFN-$ beta$ gene. Expression from the IFN-$ alpha$1 promoter …  Lire la suite

This thesis defends Adorno's critical theory of society against the charge of pessimism. Its two aims are to portray the theory's hope and to present its model for progressive social change. I argue that Adorno's pessimistic assertions concerning the closed society are not to be taken literally but understood as rhetorical devices which provoke reflection. Neither is his "negative utopia” to be read as pure criticism. It is a new vision of reconciliation that preserves the individual from subsumption under the universal, and it is this focus on the individual which the term "negative" stresses. In his constellation of utopia, …  Lire la suite

After a brief introduction, we consider three main results in the existence theory of harmonic maps between manifolds. The first is the heat-equation proof of Eells and Sampson, which says that minimal harmonic maps of compact manifolds into compact manifolds with nonpositive curvature always exist. The next two results show they exist among maps of compact Riemann surfaces into compact manifolds, N, with $ pi sb2$(N) = 0. One proof uses the induced $ pi sb1$-action of Schoen and Yau; the other a perturbation of the action due to Sacks and Uhlenbeck. As required, we also develop some of the …  Lire la suite

In this thesis we apply the Interfacial Wave Theory of dendritic crystal growth to the case in which the thermal diffusivity constant and the specific heat of the liquid state are different from those of the solid state. The problem is formulated as a linear eigenvalue problem. A quantum condition for the eigenvalues is derived and a discrete set of possible solutions is found. The selection problem is solved using the global neutral stable state analysis proposed by the Interfacial Wave Theory.  Lire la suite

Following work by Coleman and Lee using ordinary gravity, we obtain a low-energy effective Lagrangian for a supergravity system, in which superwormholes are represented by local operators in superspace. Supersymmetry is not broken by these new interactions.  Lire la suite

"Cette étude a évalué la consommation et le contenu en lipides et toxaphènes d'aliments traditionnels dans l'alimentation du peuple Sahtu (Hareskin) Dene/Métis de Fort Good Hope et Calville Lake des Territoires de Nord-Ouest. Quatre-vingt-sept des 126 ménages et 79 des 100 ménages et campements ont été interviewés durant les saisons d'été et d'hiver respectivement. Ces interviews ont permis de recueillir des informations sur les caractéristiques du ménage, et sur leur consummation alimentaire. La composition alimentaire et le contenu d'acides gras et de toxaphènes ont été analysés sur des échantillons de 67 différrents aliments traditionnels. La composition alimentaire de 38 de …  Lire la suite

Atrial natriuretic factor (ANF), a 28 amino acid peptide hormone, is the major secretory product of the heart. Because of its diuretic, natriuretic and vasodilating activities, this peptide may be involved in the maintenance of proper fluid and electrolyte balance and blood pressure control. In order to study the transcriptional regulation of ANF, we have isolated the rat ANF gene and we have established a system of cardiocytes in primary cell culture for studies on the hormonal, tissue-specific and developmental regulation of the ANF gene. Using this in vitro system, as have demonstrated that thyroid hormone increases ANF mRNA levels …  Lire la suite

Preliminary experiments by API ZYM enzyme system showed that Lactobacillus casei (Lb. casei) subspecies contained low proteinase and high aminopeptidase and esterase-lipase activities, which are the desirable traits of microorganisms to be used as starter adjuncts in Cheddar cheese-making. Six strains of Lb. casei (ssp. casei, ssp. rhamnosus, and ssp. pseudoplantarum), selected from superior peptidase and esterase-lipase profiles, were further studied for their amino-, di-, and carboxy-peptidase activities using thirty synthetic substrates. This study revealed useful information towards improving our understanding of the peptidase profiles and probable role of Lb. casei in Cheddar cheese ripening. Although individual strains varied in …  Lire la suite

Novel heteroanthracycline antitumor drugs were designed based on structure activity relationship studies and known mechanisms of drug action. Their preparation required the development of a general synthetic approach. After extensive studies, three methodologies were developed for the general synthetic plan. The first method involved photoenolisation of 2,5-dimethoxybenzaldehyde and SO$ sb2$ entrapment of the o-quinodimethane to give 4,7-dimethoxy-1-hydroxy-1,3-dihydrobenzo(2,3-c) thiophene-2,2-dioxide. This compound served as a general intermediate towards the synthesis of several heteroanthracyclinones. It could be reduced to the oxathiin-2-oxide derivative which thermally extruded SO$ sb2$ to yield the o-quinodimethane. Reentrapment of this latter intermediate with various glyoxalates gave key isochroman derivatives. …  Lire la suite

The spin-spin and spin-lattice relaxation times of protons on polymers, T$ sb{ rm 1p}$ and T$ sb{ rm 2p}$, respectively, have been used to probe the absorbed dose of irradiated polymer solutions in which radiation-induced changes in polymer molecular weight, M$ sb{ rm n}$, occur. The M$ sb{ rm n}$ dependencies of T$ sb{ rm 1p}$ and T$ sb{ rm 2p}$, and of the water proton T$ sb{ rm 1w}$ for solutions of poly(ethylene oxide) (PEO) in D$ sb2$O and H$ sb2$O are presented. T$ sb{ rm 1p}$ and T$ sb{ rm 1w}$ are independent of M$ sb{ rm n},$ …  Lire la suite

This dissertation consists of a defence of scientific realism and a critique of empiricist antirealism. Strict empiricism is discussed in Chapter 1, in which it is argued that this variety of empiricism adequately describes only the initial stages of scientific research. Bas van Frassen's empiricist antirealism is then discussed in Chapter 2. Here, it is argued that this new position, although more sophisticated than earlier forms of empiricist antirealism, fails to constitute a genuinely acceptable alternative to scientific realism. The two main constituents of scientific realism--scientism and critical realism--are then defended in Chapters 3 and 4. Lastly, the superempirical virtues …  Lire la suite

The Duplan strain of Radiation Leukemia Virus (RadLV) induces an AIDS-like syndrome when injected intraperitoneally into adult C57BL/6 mice. The mice develop T cell depletion, polyclonal B cell proliferation (lymphadenopathy, splenomegaly), hypergammaglobulinemia, and immune deficiency. This syndrome has recently been designated MAIDS (murine acquired immunodeficiency syndrome). This virus preparation, passaged in vivo, is crude and known to contain different strains of retroviruses. To identify the etiologic agent of this disease, we first infected fibroblasts in vitro with this crude virus mixture. Supernatants of these cultures induced disease. Unintegrated viral DNA from fibroblasts newly-infected with this virus preparation was extracted by …  Lire la suite

The effects of added potassium, K, magnesium, Mg and sulfur, S on corn grain and silage yields were investigated in the field for two years. Due to high nutrient soil, K, Mg and S had no effects on corn grain and silage yields. However, there were trends observed in the treatment effects that were significant. Added K at 240 kg K$ sb2$O/ha increased grain yield over zero kg K$ sb2$O/ha in 1983 and Mg at 60 kg/ha increased grain yield over 30 kg/ha in 1984. In silage, 240 kg K$ sb2$O/ha increased yield over 120 and zero kg K$ sb2$O/ha …  Lire la suite

It is commonly believed that by involving the user in the design process of his dwelling unit, a higher level of satisfaction could be achieved. Attempts have been made in several countries to include users in the design process of their units using different communication media including computers. However, today computers have been implemented primarily for the use of architects. This study aims at narrowing the architect-user communication gap by using computers in multi-unit housing design. The author reviews past work in user involvement in the design process through the use of computers and the possibility of introducing computers into …  Lire la suite

The cAMP binding protein CABP1 isolated from Dictyostelium discoideum consists of two subunits, CABP1A and CABP1B, which are produced from a single gene by an unusual splicing mechanism. To characterize this mechanism, an actin-CABP1 fusion gene was constructed and introduced into D. discoideum cells by DNA-mediated transformation. Analysis of these cells demonstrated that the transcripts derived from the fusion gene were properly processed to generate both CABP1A and CABP1B. However, when the 5$ sp prime$ splice site in the gene was mutated to conform to the D. discoideum consensus, only CABP1B was produced. These results suggest that the splicing event …  Lire la suite

High performance dc servo-drives are often supplied from four-quadrant choppers to ensure low armature current ripple and large control loop bandwidths. In order to allow for continued regenerative braking, the dc link voltage is regulated within limits and the energy produced during braking is dissipated in resistances. In the proposed scheme the energy produced during regeneration is re-injected into the ac mains supply. The scheme consists of adding to each diode of the front end rectifier a transistor capable of conducting the reverse current, and suppressing the dc link capacitor. The performance of the complete converter with a single phase …  Lire la suite

A 7.6 cm (3") Knelson concentrator was used to estimate free gold content in samples extracted from industrial grinding and gravity circuits. Its recovery was comparable with that of amalgamation and the Mozley Laboratory Separator (MLS). It was then used for a study on gold grinding and classification behavior. Laboratory studies of monosized gold and silica showed that gold produces fewer fines upon grinding: 75% of the mass reports to the next Tyler class, as opposed to 45% for silica. Disappearance from the monosized class (840-1200 $ mu$m) follows first order kinetics for both minerals. However, the rate constant of …  Lire la suite

This research attempted to examine the reasons why children and youths disclose their sexual victimization, as well as the manner of their disclosure, specific to the school setting. An original questionnaire was developed, and given out to all the school social workers from one social service agency. Each worker chose, non-randomly one case of sexual abuse disclosure. It was hypothesized that if a child or youth had decided to disclose their sexual victimization in the school setting they would do so in a planned and overt manner, choosing an adult with whom they had a close, positive and trusting relationship; …  Lire la suite

Two new techniques for the study of biological molecules using vibrational spectroscopy have been investigated, and are presented in this thesis in two parts. In Part I, the application of centrifugal vacuum techniques for sample preparation in FT-IR spectroscopy is demonstrated. This technique is used in the development of an agglutination immunoassay for bovine serum albumin (BSA) using polystyrene latex particles as both a solid support and an IR label. The synthesis of new organometallic labels for use in LPIRIA has been undertaken and is described in detail. A competitive non-agglutination LPIRIA for BSA using anti-BSA covalently bound to carboxylate-modified …  Lire la suite

"An acid-coagulated product was produced by extrusion from high and medium beat skim milk powder (SHP) and in the presence of acid as a preliminary step to the production of sodium caseinate. The medium beat SHP was more affected by extrusion variables of which only moisture which carried the ·acidulant was found to be significant. The physicochemical and functional properties (color, microstructure, bulk density, sedimentable matter, proximate composition, molecular weights, buffering capacity, molsture sorption isotherms, viscometric characteristics, solubility, meltability, foaming, emulslfication, and relative nutritive value) were studied in two caseinate systems, commercial sodium caseinate with added lactose and sodium caseinate …  Lire la suite

The dissertation develops a theory-based, state-centered revisionist explanation of the development of Canadian broadcasting policy during the years 1955 to 1968. The hypothesis contends that state officials seek their own preferred policy outcomes rather than reflecting the preferences of societal actors. The concept of decision points is used to explore the origins of the 1958 Broadcasting Act and the 1968 Broadcasting Act. The evidence suggests the content of these measures was largely determined by bureaucratic actors. Two aspects of the 1968 legislation (the power to approve broadcasting licenses and extension of broadcasting regulatory jurisdiction to cable television) are examined in …  Lire la suite

The inability to measure where an annihilation photon interacts within a detector crystal limits PET resolution uniformity by blurring the outer regions of the image. This problem is solved by dividing a scintillation crystal along its length into two regions, by a black absorbing band, that are equally likely to absorb a PET photon. Light collected from the front and back of the crystal allow the region of photon interaction and photon energy to be determined, using dual parameter acquisition. The design was tested by sweeping a radiation beam across a bismuth germanate crystal detector. The percentage of incorrectly positioned …  Lire la suite

Since life-threatening natural phenomena, such as, snow avalanches and lava flows, and many industrial and agricultural material handling processes may be classified as granular flows, establishing constitutive relationships which model granular flow behaviour is of prime importance. While laboratory experiments attempting to support granular flow theory have been plagued by poor instrumentation, numerical simulations are becoming increasingly helpful in understanding the nature of these flows. The present investigation describes such a simulation developed within the framework of the Direct Simulation Monte Carlo model for rarefied gases presented in Bird (1976) and granular flow kinetic theory according to Lun, et al. …  Lire la suite

Theatre has a special place in religious education for it is an ideal medium to experience transcendent moral truths. Relying on Gabriel Moran's theory of transcendence, as well as Daniel Maguire's understanding of the moral, this thesis will demonstrate that the aesthetic experience of a play is a transcendent experience. Through such an experience, adolescent students may intuit insights about what befits persons as moral persons in all their complexity and wonder. The plays chosen for concentration in this thesis are not to be considered exhaustive but only as sound examples of the treatment of the evolution of transcendent values …  Lire la suite

CEGEPs (Colleges d'enseignement general et professionnel) were designed with the aim of developing intellectual abilities in young adults. The purpose of this study was to describe the cognitive and affective abilities of CEGEP students at the beginning and end of CEGEP and to measure the change in these abilities. Comparing student cognitive and affective abilities at the beginning of, during and at the end of CEGEP, according to known measures of student development, would establish what changes occur during the college years, and would thereby promote a more thorough understanding of the students which CEGEPs serve. The cognitive development of …  Lire la suite

Most elderly persons with dementia are cared for at home, usually by a spouse or adult child. The objective of the present study was to determine whether there is an excess of psychological and physical health problems among family caregivers of elderly persons with dementia. Data were obtained by interview from close family members of dementia patients, and from a comparison group made up of close family members of patients undergoing cataract surgery. Caregivers had significantly higher levels of depression and physical symptoms than noncaregivers. The association between caregiving and the outcome variables was stronger among subjects who were married …  Lire la suite

The experiments reported in the present dissertation investigated the contribution of the pyriform cortex and of the basolateral amygdala to three classes of affective behavior: conditioned aversions, conditioned preferences, and neophobia. It was demonstrated that lesions of the pyriform cortex cause an impairment in the acquisition of aversions to olfactory, but not gustatory, stimuli and that this impairment is not secondary to alterations in primary olfactory function. The acquisition of a preference for a particular odor paired with reward was also shown to be impaired by such lesions. These results are discussed in terms of the rich innervation of the …  Lire la suite

Kant's rejection of rationalism starts in 1755 with the analysis of Leibniz's two metaphysical principles. Kant's preoccupation in this first essay is the source of necessity. He shows the logical nature of Leibniz first principle and the weaknesses of the second. He finally demonstrates the falsity of the corollaries. This final step directs Kant to a recognition of the over intellectual nature of Leibniz' s method. In 1763, Kant writes Versuch, den Begriff der negativen Grossen in die Weltweisheit einzuffihren and it is there that he finds the source of the necessity that he was seeking. By distinguishing between logical …  Lire la suite

Indices of nutritional condition and diet were evaluated in harp seals Phoca groenlandica obtained from hunters in Hudson Strait and the Gulf of St. Lawrence, December 1988 to October 1990. In winter seals, blubber and the lean, eviscerated carcass contributed 90% and 9% of total body lipids, respectively. Lipid was distributed homogeneously throughout the blubber. Blubber thickness and girth at 50% of length showed the strongest correlation to fat stores. Sculp and core mass in females increased from autumn to winter. Mature males were observed to significantly increase their blubber mass from early to late winter. Muscle and liver lipid …  Lire la suite

Acoustical reverberation has been shown to degrade the intelligibility and naturalness of speech. In this thesis, we discuss the application of cepstral methods to the enhancement of acoustically reverberant speech. We first study previously described cepstral techniques for removal of simple echoes from signals. Our results show that these techniques are not directly applicable to the enhancement of speech of indefinite extent. We next recast these techniques specifically for speech. We propose new segmentation and windowing strategies, in combination with cepstral averaging, to accurately identify the acoustical impulse response. We then consider inverse filtering based on an estimated acoustical impulse …  Lire la suite

The method of Weyl orbit reduction for obtaining branching rules is extended to affine Kac-Moody algebras. The orbits of affine rank 2 and 3 algebras are obtained analytically and the fundamental orbits are decomposed into irreducible representations (I.R.). Numerical inversion of a triangular matrix then gives the orbit multiplicities in an I.R. Orbit to orbit branching rules are deduced for selected subalgebras and used to produce I.R. to I.R. branching rules.  Lire la suite

Members of the HSAG family of genetic elements stimulate amplification of the pSV$ sb2$DHFR vector in cis, such that HSAG-pSV$ sb2$DHFR transfected cell populations generate methotrexate resistant cells at a higher frequency than pSV$ sb2$DHFR transfectants. Repetitive DNA sequences such as Alu elements were found in HSAG-1, HSAG-2, and HSAG-5; HSAG-1 and HSAG-2 also contain poly purine-pyrimidine tracts. Analysis of subfragments of HSAG-1, HSAG-2, and HSAG-5 demonstrated that the interaction of multiple positive-acting elements was necessary for maximum amplification stimulatory activity. Proposed positive-acting elements include Alu-like sequences, poly purine-pyrimidine tracts, A/T rich regions and potential stem-loop structures. For HSAG-1, the …  Lire la suite