McGill University Thèses et mémoires publiés en 1951

The basic principle of the method of three-phase symmetrical components is the resolution of any particular set of vectors, current or voltage, in the three-phases of an unbalanced electric circuit into three sets of balanced three-phase vectors, i.e., the positive-sequence, negative-sequence and zero-sequence symmetrical components. [...]  Lire la suite

A method of heat treating uranium oxide semiconducting material by passing through it a current many times its rated value, is given. The resulting change is permanent and it can be controlled to obtain any desired resistance over a wide range. An outline of the factors involved in the heat treatment process is presented along with a theoretical explanation of the observed results.  Lire la suite

In the summer of 1949 a field party of the Geological Survey of Canada made a reconnaissance survey of the Labrador coastal region. In the course of the summer a section of the coast and the coastal islands between Domino Run and Hamilton Inlet were studied. Here the Labrador coast, which is relatively unexplored, was found to consist mainly of a grey granite gneiss which had been intruded by basic rocks of at least two ages. The older of the intrusive rocks are garnet-bearing and have since been found to contain well-developed reaction rims. Parts of the garnetiferous gabbro-diabase, which …  Lire la suite

The economic revolution which transformed England from a grower and exporter of raw wool, to a producer and purveyor of manufactured cloth, began and was in a large part accomplished during the fourteenth century. [...]  Lire la suite

Convalescence, derived from the verb to convalescence, which means to grow strong, is the subject of this study. Although the principle of convalescence has been practiced for hundreds of years, its definition has taken time to evolve. Dr. Woodruff^1 has formulated the following: "According to the Oxford dictionary the word convalescence, in its present medical meaning, did not come into use until the 19th century. Before that a person was ‘sick’ or he was ‘well.’ Now, convalescence is recognized as a state of gradual recovery from illness. In other words, the term convalescence is applied to the transitory condition when …  Lire la suite

Electrodeposition of metals may be divided into four categories. In electroplating, articles are coated with a layer of metal for the purpose of ornament or protection. The physical form of the deposit is of prime importance since upon it depend such properties as lustre, hardness and ductility. Good adherence of the deposit to the plated article is also a requisite. The process of electroforming is the production or reproduction of articles by electrodeposition. Reproduction of printing plates and phonograph matrices are common examples of electroforming. In electrorefining, the anodes consist principally of the metal to be refined. The purpose is …  Lire la suite

In 1916 Lanthrop and Loeb (l) demonstrated a diminished incidence of spontaneous mammary cancer in female mice of known high incidence strains as a sequel to castration. This observation clearly implicated the ovarian hormone secretions (2), acting in conjunction with hereditary factors, in the transformation of normal to cancerous tissue in the mammary gland. [...]  Lire la suite

In recent years there has been an increasing interest in the field of insect microbiology. There are several aspects to this relatively young science and each has contributed to this increasing interest. Among the more important aspects are the following: a) symbiotic relationships between insects and microorganisms, b) human, animal, and plant diseases carried by insects, c) epizootic diseases among insect populations. The control of destructive insects through the agency of microorganisms has been a rather controversial subject since the beginning of the century. Several workers have noticed the spectacular effects of naturally occurring epizootics and have tried to duplicate …  Lire la suite

An understanding of the mechanisms operating in nuclear reactions produced by high energy nucleons is of considerable interest. The experimental investigation of these processes may be grouped into two categories: l. Measurements are made of the excitation function for the production of a certain isotope. 2. The energy and angular distributions of the emitted partiales are studied. [...]  Lire la suite

Cancer of the stomach is the most frequent of all malignant growths. Livingston and Pack in 1939 (121) have stated: "There are more deaths from cancer of the stomach than from all malignant tumors of lip, tongue, cheek, tonsil, pharynx, larynx, salivary glands, thyroid, male and female breast, ovary, uterine cervix and corpus uteri combined." [...]  Lire la suite

The experimental work which follows represents one in a series of clinical and research investigations undertaken at the Montreal Neurological Institute aimed at the solution of the problem of epilepsy. In a previous thesis the author has reviewed the social and medical history of epilepsy and summarized the present state of scientific knowledge about this disease (Tower, 1948). The facts presented therein make it clear that epilepsy is one of the important diseases confronting society and the medical profession and demanding a solution. The present state of world conditions underlines this demand, since war carries with it an inevitable aftermath …  Lire la suite

The classification of plants has involved an enormous amount of work on the part of a large number of botanists. It is based on the natural affinities of plants- and has been guided by the concepts of evolution. The tools of the taxonomist have been mainly morphology, anatomy, embryology and palaeontology. However, in many cases it has been impossible to construct accurate phylogenetic relationships. It becomes important, therefore, to discover additional means whereby some of the problems of taxonomy may be resolved. As Gibbs (33) and others have pointed out, the comparative chemistry of plants provides another source of evidence …  Lire la suite

The purpose of the present work is to present to the Grenville student an idea of the general structure at a scale of 8 miles to the inch, along with a description of the broad tectonic features and relationships existing between many physiographic and geologic components of the whole belt. The work was originally planned to include Ontario as well but since J. Tuzo Wilson undertook the compilation of the structure north of the 45°30’ parallel (with far better means than the writer had at its disposition such as aerial photographs, drauftsmen and secretaries) the part of Ontario that is …  Lire la suite

Maass, O. (Supervisor)  Lire la suite

The large general hospital which has an obstetrical service plays an important role in the community in terms of maternal care. When, in addition, it maintains an outpatient clinic, it is in a position to encourage adequate pre-natal care as part of its programme. [...]  Lire la suite

The experimental material to be reported in this thesis represents the results of work carried out by the writer since the end of World War II. The studies arose out of three large surveys which were carried out under the direction of Dr. O.F. Denstedt of this department during the war. [...]  Lire la suite

The polarographic method of chemical analysis was introduced by Professor J. Heyrovsky in a series of papers published between 1922 and 1926. The method is based on interpretation of current-potential curves obtained when electroreducible or electro-oxidizable substances are reduced or oxidized at a dropping mercury electrode. The complete cell consists of a dropping mercury electrode, and another electrode which is essentially non-polarizable. The curve obtained by plotting the external voltage applied to the cell against the resulting current is the current-voltage curve, and since the one electrode is non-polarizable, this curve is actually the current-potential curve of the dropping electrode. …  Lire la suite

This study of the arterial supply to the ureter was made because of the prevalence of injuries to the ureter in pelvic surgery and gynecologic complications to the ureter and kidney following pelvic intervention. [...]  Lire la suite

The present trend in psychiatric clinics is for the patient to have his initial interview with the caseworker. The first interview or interviews which the patient has with the caseworker, before he is assigned to a psychiatrist in the clinic, is the process known as social intake. There is a considerable amount of literature available on this subject and several articles have been published in the last few years about psychiatric clinics by both psychiatrists and caseworkers. It is probable that gradually growing acceptance of psychiatry on the part of the public has increased the demand for treatment in psychiatric …  Lire la suite

With the increased use of weldments and other alternate methods of fabrication over the past few years, there has been much interest in the foundry industry in improving the quality and over-all reliability of steel castings. In recent years, also, the efficiency of the acid-electric steelmaking process for the intermittent operation peculiar to the industry has been reflected by an increasingly larger proportion of the steel used to make castings produced by this method. [...]  Lire la suite

A description is given of the design and construction of two cloud chamber cameras designed for automatic operation in the magnetic field of a cyclotron, one camera being a single lens instrument for preliminary investigation and the other a double lens stereoscopic camera. Modifications to the cloud chamber and its auxiliary equipment for work in conjunction with the cyclotron are also described, and sample photographs obtained with the two cameras are presented.  Lire la suite

The research problem with which this investigation is co-ordinated was undertaken by Dr. Kenneth A. Evelyn as part of a long-term study of the natural history of essential hypertension ( 1 ). His general working hypothesis at the commencement of his study was "the concept that the pathogenesis of essential hypertension involves a genetically determined abnormality in the contractile mechanism of arteriolar smooth muscle, rather than a derangement of the neurogenic and humoral factors which regulate this contractility”. The first phase of this study was the investigation of the chemical composition of arteriolar smooth muscle. Later, it is planned to …  Lire la suite

Par la fenêtre, ouverte sous l’abîme nocturne, je percevais l’angoissa des êtres. Mes deux plus proches voisins, les tilleuls jumeaux qui se dressaient, près de la porte, comme des serviteurs attentifs, devisaient le soupir de chaque feuille ramant dans les ténèbres. Et moi-même, cette nuit-là, n’étais-je pas plus sensible que l’épi des graminées, plus frémissant que la vrille des vignes folles?1 Ces lignes pénétrantes et révélatrices sont les premières d’un roman de Georges Duhamel ou, comme cet écrivain le fait si souvent, il s’abandonne a son premier élan: peindre la via comme alla apparaît a l’oeil averti qui a tôt …  Lire la suite

The first fifty years of the twentieth century has witnessed remarkable developments in our Canadian schools. This same period has been one of extensive social, industrial and political expansion, all of which is reflected in the changes seen in our educational system. From being almost wholly academic institutions, the schools have gradually evolved a newer concept of what constitutes a well rounded general education. Influenced by the suggestions made by research committees, educational surveys and individual studies, most educationalists have now agreed that the older academic courses must be vitalized and integrated with the other practical, physical and social factors …  Lire la suite

It would be hard to name a papaer or date which might be regarded as the starting point for the study of the effects of radiation on bacteria. The history of this field has been very gradual in development and in most cases, dependent upon the advances of the other basic sciences and especially upon our increasing knowledge of the behavious of microorganisms. The credit for the "discovery" of the lethal action of sunlight on bacteria is generally given to Downes and Blunt (50, 51) who in 1877 showed that certain organic substances in solution which would normally undergo decomposition …  Lire la suite

In 1870, Timothy Holmes, in a discussion of atheroma, wrote, “The gouty, the aged, the rheumatic, the persons whose tissues are imbued with fat, and those whose excretory organs fail to purify the circulating blood, are more prone to this disease, than the phthisical, the cancerous, or the young.” Since that time evidence has accumulated that arteriosclerosis, with its crippling and often fatal effects, is more common in the obese, less common in those whose tissues are wasted. The study of arteriosclerosis in man, especially during its developmental stages, is beset with difficulties. The study of cholesterol- induced atherosclerosis in …  Lire la suite

In 1927 Dorothy Needham (l), observed that when glutamic acid was added to minced pigeon breast muscle it disappeared without a parallel formation of ammonia, or a decrease in the total amino group concentration. She assumed,that the amino group of glutamic acid was transferred to some reactive carbohydrate residue to form a new amino acid. A similar phenomenon was observed by Banga and Szent- Gyorgyi (8), who noted that the rate of oxalacetic acid disappearance from pigeon breast muscle preparations was increased by glutamic acid. However, they did not recognize this as a transamination reaction. The correctness of Needham’s assumption …  Lire la suite

Joris-Karl Huysmans nous apparaît comme un Goldilocks énigmatique du dix-neuvième siècle. Il va chez les trois ours. Sans beaucoup attendre, il se dit: Voyons, je meurs de faim! Mais la bouillie du père ours s’est refroidie; et la bouillie de la mère ourse est trop cuite. Quant à la bouillie de l’ourson...et ici le conte déraille... elle ne suffit pas; ou elle a disparu: elle s’est figée, ou elle lui soulève le coeur. Notre pauvre Goldilocks se trouve dans l’obligation de chercher un autre bol de bouillie, recherche, hélas, qui prend vite les proportions d’une manie. Et comme ce Goldilocks, …  Lire la suite

The hormones are of fundamental importance in correlating the metabolism of an organism as a whole by causing changes in the vital processes of its specific tissues. Malfunctioning of one or more of the endocrine mechanisms may result in profound disturbances in or even death to an animal. Administration of crystalline hormones or extracts of these highly active substances elicits effects which have been carefully determined. Such physiological responses are more or less transitory in nature tending to demonstrate that the hormones are rapidly transformed to inactive substances. Because of their marked physiological actions, a large volume of work has …  Lire la suite

The Lucy Orebody is a deposit of iron carbonate (siderite) located in the Michipicoten district of Ontario. Field information for this thesis was gathered during the summer of 1950 while the writer was in the employment of Jalore Mining Company, Josephine, Ontario, and laboratory investigations were conducted at McGill University. In this thesis the petrology, structure and origin of the rocks in, and adjacent to, the orebody will be discussed. Acknowledgements The writer wishes to acknowledge his indebtedness to Dr. J. E. Gill for his supervision of this thesis and his many valuable suggestions and helpful advice. To Dr. E. …  Lire la suite

The problem of radiation losses from high frequency parallel-wire transmission lines was first realized as early as 1900, and has become a matter of controversy ever since. Many writers have investigated the problem from a theoretical standpoint, but very little has been done in the way of measuring these losses experimentally. At low frequencies radiation losses are negligible, but they become appreciable at high frequencies thus affecting the design of parallel-wire lines for use in the higher portion of the frequency spectrum. In order that the controversy may be wholly or at least partially settled, and to correct existing data, …  Lire la suite

Thirty years of intensive research have demonstrated the importance of the physiological role played by the steroids. The more recent investigations relating to the hormones of the adrenal cortex, which have led to the use of synthetic steroids in the treatment of diseases of mal-adaptation, represent a crowning achievement of the co-operation of the biological and chemical sciences. Yet, these remarkable discoveries should not, in any way, obscure the enormous gaps in our knowledge of the metabolism of these substances, but should instead pave the way to a thorough study of the many problems that remain to be solved. Many …  Lire la suite

Cholesterol is a waxy, crystalline substance of definite molecular weight, having the empirical formula C27H46O. Its melting point is 147.5 - 148.5°C. The established system of designating the rings by letter and the numbering of individual carbon atoms accompany the structure at this time. Hereafter, the location of various positions by number may be made by reference to this formula. The parent hydrocarbon, cholestane, may be derived by completely saturating cholesterol with hydrogen. This provides us with a basis of naming members of this series. Thus, cholesterol would be completely identified by Δ^5-cholesten-3 (β)-ol, where the Δ signifies a double …  Lire la suite