McGill University Thèses et mémoires publiés en 1948

Any study which purports to investigate the pathogenesis of arteriosclerosis must be considered of interest to both pure and applied science. There are few fields of biological research which touch upon so many fundamental problems as does this. It matters little whether one is concerned with the interfacial behavior of films, with the metabolism of lipids, with the behavior of extracellular protein, colloids and gels, or with the problem of ceiiuiar movement and irritability, for all these and many more may find some application in the stuay of this disease. Ana similarly, if one is more immediately concerned with the …  Lire la suite

The subject of this thesis is admittedly of so general a nature that if no limits were imposed its ramifications might well produce a work rivalling the Encyclopaedia Britannica. However, the object which I have in mind is of a much more limited nature and demands some elucidation. I have no intention of writing a comprehensive military history of the period, nor in particular of the concluding battle of the Plains of Abraham and its aftermath, if only for the negative reason that so much has already been said.[...]  Lire la suite

This project deals with factors in absenteeism in two of the Montreal Protestant Schools during the period beginning with September l, 1945 and ending with February 28, 1946. The schools chosen for this project ware located in crowded industrial sections of the city where housing was substandard and recreational facilities were poor. Nearby water front activities of one area and the proximity of industrial development in the other area were responsible for a crowding of families who were seeking suitable employment. Absenteeism in these two schools has been a problem tor many years, according to the records of the Montreal …  Lire la suite

For many years there has been a well-sustained Interest in ion-sources which are of vital importance for the efficient operation of positive ion accelerators such aa Van de Graaffs, high tension sets, and cyclotrons. In the present search two types of oscillating electron beam sources have been tried. One employs a hot filament cathode, the other a cold cathode. The hot filament source appeared to be very promising at the time. An ion output of 2 mA, containing an estimated 50% of atomic ions, was obtained from it. Difficulties such as contamination by evaporation from the filaments, a tendency toward …  Lire la suite

In recent years there has arisen a great clinical interest in the lungs. This is evidenced by the development of special thoracic branches of medicine and surgery and the publication of periodicals devoted solely to these fields of medical science. A natural result of the increased clinical importance of the lungs has been a focusing of attention on the anatomy of these organs, but, in spite of this, little attention has been given to the possible significance of their lobation. It is surprising that this should be so, as pleuritic fusion of the pulmonary lobes is not an uncommon occurrence. …  Lire la suite

Three general methods for the estimation of soil organic matter are in common use, loss on ignition, oxidation by heating in air or in oxygen with measurement of the carhon dioxide evolved, oxidation with hydrogen peroxide solution and oxidation with dichromate in acidic solution, the organic matter being estimated whether from the carbon dioxide evolved or indirectly from the quantity of dichromate reduced. None of these methods, with the exception of loss in ignition in case of certain types of soils, gives an absolute measure of the organic matter content. The loss on ignition technique is subject to many sources …  Lire la suite

It has been observed in this laboratory (l) that the addition of potassium persulphate to a monomer-free latex of butadiene-styrene copolymer will promote a crosslinking reaction, the rate of which was directly proportional to the concentration of persulphate ion. This cross-linking reaction was thought to be due principally to the presence of unsaturation in the polymer, but there did seem to exist the possibility that even saturated hydro carbon chains might undergo similar cross-linking under certain conditions. Consequently, it seemed worth while to determine whether such a reaction might be induced to occur between saturated polymer molecules in solution in …  Lire la suite

This paper describes some of the development work undertaken by the author on an electronic synchronous speed regulating system for the National Research Council of Canada. Its purpose is to show how a control system of this type may be analysed by means of servomechanism theory, and the methods by which stable operation may be obtained. No originality is claimed for the principle of control or for the methods of analysis used here. However, the actual analysis of this control system and its proposed stabilization, has not, to the author1s knowledge, been covered elsewhere in the literature. The bibliography contains …  Lire la suite

Special photographic emulsions developed to record the tracks of charged particles hâve been exposed to cosmic rays at high altitudes by being carried in aircraft on trans-Atlantic flights. Total exposure times of more than 200 hours above 10,000 feet, with more than half being above 15*000 feet, were achieved, Microscopic examination of the plates disclosed a large number of nuclear disintegrations produced by cosmic rays. Detailed study of thèse disintegrations revealed several types not previously reported. Mesons were observed which produced at the end of their range a single proton, a single alpha particle, or one or more of each, …  Lire la suite

The sedimentary, volcanic and intrusive rocks of an area in the northern part of the Canadian Shield are described. Particular reference is made to the relative ages of these formations* their structures, and to major faults. The field evidence suggests that a red feldsparporphyry intrusive is younger than the granite which intrudes the volcanic porphyries. This, and to some extent the stratigraphic sequence proposed differ from previous findings. The distribution and attitudes of the sedimentary and volcanic formations indicate a flexure in a regional northv/esterly-trending open fold- Two sets of right-hand faults strike northerly and northeasterly respectively. The latter are …  Lire la suite

This thesis is composed of four chapters, each dealing with a separate problem related to surgery of the heart and lungs. The work was performed in the Departments of Experimental Surgery and Physiology at McGill University. In Chapter I, a description is given of a new method of preparing dogs for the study of metabolism. As will be pointed out, such preparations need not be restricted to this study but can be used to investigate several other problems. A review of the literature dealing with the bronchial vessels, as outlined in Chapter 2, emphasizes their importance to the physiology of …  Lire la suite

The seed hairs of the typha family (cat-tails) are easy to collect and appear to the eye to consist of cellulosic fibers of nearly uniform length radiating from a central stem. The object of the present Thesis was to review the literature concerning the chemistry and possible uses of the typha plant and to Supplement existing knowledge concerning the chemical composition and properties of the seed hairs. It was found that Standard methods of wood analyses gave inconsistent results with typha seed hairs and an effort was made to discover why such methods were unsuitable in this particular case.  Lire la suite

A digestibility study was conducted in which an identical diet was fed to five species, namely, rats, pigs, sheep, guinea pigs and humans. The diet consisted mainly of whole wheat. As fed, it was found to be unsuitable for digestibility studies with guinea pigs. With sheep, a basal hay diet was fed and digestion coefficients determined indirectly. Variability between individuals was relatively low, for all species, for food fractions other than crude fiber and ether extract. Humans digested crude fiber to the same extent as pigs and rata. The range of the digestion coefficients for crude protein, nitrogen-free extract and …  Lire la suite

During the past twenty-five years the wheat stem sawfly, Cephus cinctus Nort., has become one of the worst pests of wheat in the prairie provinces. Annual losses in the wheat-growing area of Saskatchewan have been estimated at up to seventeen million busheis (Farstad, 1945). This would seem to indicate inadequate natural control. There are, however, several native parasites of this pest, and of these Microbracon cephi Gahan is the most important. In some areas this parasite has been very effective in reducing severe sawfly infestations.[...]  Lire la suite

Thulium, in the form of Tm203, has been made radioactive by neutron irradiation In a pile. The radiations have been investigated by a magnetic beta-spectrometer and by absorption methods. A conversion line is found at an energy of 0.0682 +/- .0011 Mev. and indicates a gamma ray of 0.129 +/- .003 Mev. The beta spectrum is found to be complex as the result of a Kurie plot with apparently three components whose end points are 0.953 +/- .020 Mev., O.526 +/- .020 Mev., and 0.30U +/- .020 Mev. The intensities are, respectively, 74%, 18%, and 8% as Judged by the …  Lire la suite

The presence of boron in plants was first recorded by Mittstein and Apoiger in 1857, who were able to find boric acid in the ash of seeds of Maesa picta, an Abyssinian plant belonging to the order Myrsinaceae. More recent workers have shown that boron occurs in small proportions in the ash of many kinds of plants. In 1910 Agulhon published results of experiments showing increase in dry weight, over that of control without boron, of wheat, oats, and radish grown in sand cultures with 0.5 mg. of boron per kg. of sand.[...]  Lire la suite

In September, 1911, Italy declared war on Turkey and proceeded to the conquest of the vilayet of Tripoli, a North African province of the Ottoman Empire. This thesis will attempt to determine the effect of this war upon British policy during the critical period just prior to the First Great War.  Lire la suite

[...] The Italo-Turklsh War was singular in many respects. Although most of the fighting took place in Africa the real importance of the war lay in its effect upon European politics. Because of Italy's naval superiority the Turkish forces in Africa could not be reinforced, with the result that the two opponents could not actually come to grips with one another. It became a war which was at once half European and half colonial, and one in which no decisive battle could be fought between the belligerents. The question posed by this war was not who would possess Tripoli, but …  Lire la suite

Platonic Philosophy as a whole is a movement upwards. It is the approach to an ideal, to an absolute end which exists of its own right. It does not offer a system in which all the component ideas are located in a specific place, and it does not force us to study these separately and then bring them together into an artificial whole. We can consider Plato's Philosophy from different points of view: his Ethics, his Epistemology, or his Politics, but every one of these points of view is so concerned and intermingled with the rest that an isolation of …  Lire la suite

It is an obvious and well-known fact among urban dwellers, that the two main physical problems in central areas of cities - traffic congestion and the lack of sun, light and open space - are caused by the overcrowding of land by buildings and an archaic traffic system. In these areas, where high building density prevails, the design and siting of buildings closely controls the amount of natural light which has access to them. Before the advent of elevators, the height of buildings was fairly limited by various practical considerations, such as, the number of flights of stairs which people …  Lire la suite

The increasing utilization of higher frequencies and pulsed techniques in radio engineering requires the re-examination of the behaviour under these conditions of the individual circuit components. This thesis deals with the frequency characteristics of fixed composition type resistors (both the carbon rod and metallized film type) such as are commonly used in radio and allied apparatus. The phenomenon of the decrease in resistance with increasing frequency is investigated theoretically and experimentally. The equivalent circuit of the resistor at high frequencies is determined by measurement. The effect of the frequency characteristic on the power dissipated by a resistor under pulsed conditions …  Lire la suite

Bone formation may be studied from two different aspects; the morphological, which reveals the existence of various modes of ossification, and the biochemical, which shows the deposition of calcium phosphate in all types of bones and teeth. The correlation of morphological and biochemical findings has been hailed as the way to an understanding of where and how the salts coming from the blood are deposited in the growing bone. (Policard and Roche). This information is important not only for the deeper understanding of ossification, but also for the knowledge of fracture healing, rickets, and other bone disturbances.[...]  Lire la suite

On all sides, one hears appeals to objectivity and exhortations to be objective. These admonitions are usually made by scientifically-minded people. Laudable as these appeals may be, they are sometimes so framed as to give the impression that objectivity is a quality or property of events that is immediately recognizable. It is thus, a finality, an ultimate for knowledge, which, when recognized, is taken as given. Ulterior questions, as to what constitutes the objective character of fact, are considered spurious meanderings of minds intent on weaving a cosy scheme of the universe.[...]  Lire la suite

The importance of preparing hormonal steroids containing an isotopic carbon atom has been well recognized. As the metabolism of these substances is still poorly understood, the tracer technique should become a very useful tool to elucidate the pathways of the steroid hormones in the animal organism. We have been concerned with the problem of preparing labelled steroidal compounds in this laboratory. The main idea has been to open one of the rings in the steroid nucleus, introduce an isotopic carbon atom and regenerate the original steroid molecule for subsequent use. Among the four rings of the steroid molecule, ring A …  Lire la suite

As the pulsating jet engine has been accorded little publicity in any respect apart from its notorious use as a prime mover for the "V-l" type of missile, its mode of operation may be relatively unfamiliar to those well acquainted both with the conventional forms of internal combustion engines and with the more widely employed turbo-jet. Accordingly, there follows a brief description of this engine and its mode of operation. Basically, the engine consists of a shaped metal tube fitted with one-way flow check valves at the forward or "intake" end. [...]  Lire la suite

Chromite has long been considered as one of the more important strategic raw materials. Its indispensability in the manufacture of alloys makes it vital to the nation's industrial life. The great bulk of the mineral is consumed in the form of ferrochrome, an alloy containing 60 to 70 per cent chromium, which is used in making alloy steels. Pre-war time specifications for ferrochromium required that it should contain 68 to 69 per cent chromium. Since 194l these specifications have been lowered to between 60 and 63 per cent chromium so that low-grade ores could be utilized. [...]  Lire la suite

At the present time all known methods for the hydrolysis of proteins are subject to serious limitations. Enzymatic hydrolysis is slow and incomplete, alkalis racemize the optically active amino acids and destroy cystine and arginine, and acid hydrolysis is accompanied by humin formation and tryptophane destruction. The destruction of tryptophane during acid hydrolysis is not, in all cases, due to the direct action of the acid since pure tryptophane is relatively stable in hot dilute sulphuric and hydrochloric acids. The destruction must, therefore, be due to some other constituent or constituents of the protein. Consequently, there is some reasonable prospect …  Lire la suite

The Helminthosporium diseases of cereals have been receiving an increasing amount of attention during the past twenty-five years* This has been due to a more general realization that these diseases cause important losses every year in the grain growing areas of the world. In a pamphlet Issued by the Dominion Laboratories of Plant Pathology in 1933, it is stated that In Manitoba and Saskatchewan alone the loss from root rot caused by Helmintho sp orium sativum P.K. and B. amounts to millions of dollars annually. Machacek in 1943 concluded from the results of a three-year survey in Manitoba that this …  Lire la suite

As early as 1877 Pasteur noticed inhibition of the growth of the anthrax bacillus by certain air-borne contaminants and two years later DeBary emphasized the significance of the antagonistic interrelations among microorganisms. At about the same time another worker (87) noticed that certain bacteria disappeared much more rapidly in unsterilized soils then in sterilized soils, and it was even suggested that the substances produced by the dominant organism might be of use in the control of bacterial infections. [...]  Lire la suite

Trichinosis as a human disease has its roots in antiquity, but no positive knowledge of the nature of the disease was obtained until the 19th Century, with the discovery of the worm itself by James Paget, a first-year medical student at St. Bartholomew's Hospital, London. This discovery laid the foundation for further investigation, until finally, the life-cycle of the causative organism, Trichinella spiralis, a parasitic nematode, was elucidated, and possible means of control and diagnostic techniques developed. Although the serological aspects of Trichinosis have been investigated extensively, it was felt that there still existed a need for further information on …  Lire la suite

The neutron current and density of a uniform neutron stream may be determined by inserting a disc-shaped neutron detector at right angles to the direction of the stream and measuring the activities induced over the front and back surfaces of the detector. The sum of these two activities will be referred to as simply the "activity" of the detector. [...]  Lire la suite

Most investigations with radio frequency electrical fields have dealt with their effect on physical properties of molecules, but only a few studies have been made to determine whether they could affect chemical reactivity and these report conflicting results. In an effort to settle the question, Bryce (1) and Genge (2) investigated the effect of radio frequency fields on the catalyzed and uncatalyzed polymerization of styrene. The problem dealt with in the present thesis is an outcome of their work. [...]  Lire la suite

Is it possible to correlate the source of an Aerobacter strain with some biochemical property? An answer to this question would be of value in the bacteriological analysis of water and soil for fecal contamination. It would also be valuable in medical bacteriology to differentiate intestinal forms from those derived from soil and water on uncooked foods. At present, water is oondemned by public health authorities on the basis of the presence of any member of the coliform group. Standard Methods (1946) defines the coliform thus; nIt is recommended that the coliform group be considered to include all aerobic and …  Lire la suite

Although the products of the metabolism of the adrenal cortical steroids have not been definitely established, two groups of urinary substances are believed to be derived from the adrenocortical hormones. These are the cortically active material present in lipid extracts of urine and the urinary 17-ketosteroids. Almost nothing is known of the chemical nature, or of the adrenal precursors, of the urinary corticoids; and although the chemical identity of the 17-keto- steroids has been largely elucidated, their precursors are also unknown. [...]  Lire la suite

Hughes, J. (Supervisor)  Lire la suite

The study on *Case Work with Single Women in a Psychiatric Setting, was undertaken in the Social Service Department of the Allan Memorial Institute of Psychiatry. This study set out to find the nature and effectiveness of case work help in returning to the acommunity a better adjusted person. The study involved the analysis of thirty-five social service records on single women between the ages of sixteen and forty-five years.[...]  Lire la suite

It is well known that a number of microorganisms including bacteria and fungi are carried on and in seeds of barley and other cereals. Some of these organisms are known to be destructive parasites but most of them have been considered to be saprophytes and to a large extent ignored. Little is known concerning the role that they play either in relation to the development and behavior of the seed itself or to disease development caused by the parasites carried on the seed.  Lire la suite

This is a study of the morphology and systematics of the order Conularida, as currently restricted, that is to the genus Conularia as generally thought of until 1928., This order consists of animals of unknown nature, now represented in rocks-of Palaeozoic age by phosphatic tubes which were their coverings in life. At one time the Conularida included a wide variety of more or less tubular shells, but some of these have been shown to be worms, others to be pteropods, and all the calcareous forms, Kyolithes, Tentaculites, Styliolina &c., have been removed to other groups. [...]  Lire la suite

This study was begun on the suggestion of two physicians in the Allergy Clinic at the ChildrenTs Memorial Hospital in Montreal. They had noted that, out of a group of about one hundred and twenty-five children whom they were treating, most responded well to treatment but a few responded poorly. All were receiving the same instructions and medications. The physicians believed that there might be social and/or emotional factors which hampered the response to treatment in certain cases. It was for this reason that they consulted the Social Service Department of the hospital in regard to a special review of …  Lire la suite

The experimental work which forms the basis of this discussion represents the first report of a long term investigation under the direction of Dr.Boris P. Babkin. It is a privilege to acknowledge his able and enthusiastic direction, his keen and logical criticism as well as his active participation in many of the experiments. We are grateful to Dr. Wilder Penfield for suggestions regarding the general course of the investigation and for the inspiration of his own work in man.[...]  Lire la suite

This survey was undertaken in the hope of extending our knowledge of the Appalachian Mountain System and i t s erosional history by study of the topography of part of the System in Canada, The area studied lies chiefly in the Eastern Townships of Quebec, where the Appalachians cross with a northeasterly trend, south of the St.Lawrence River, and north of the United States border. This part of the Appalachians in Canada is, in the main, a continuation of the Green Mountains of Vermont and is known as the Notre Dame Mountains. The System also includes the Sutton and Megantic …  Lire la suite

The study reported herein was carried out by cooperation of the Departments of Agronomy and Animal Nutrition. The lignification study reported was conducted with three grasses, viz, Timothy, Brome and Reed Canary grass, while the digestibility study was conducted with Timothy only. A method of estimating the percentage of lignified area in plant tissue is described and has been used throughout the study. The percentage of lignified area in the stem increased as the plant matured. In Timothy and Brome grass the percentage of lignified area increased as one progressed up the culm. With Reed Canary grass the reverse was …  Lire la suite

In spite of almost half a century of study the exact mechanism regulating the blood sugar level of animals has not been finally and satisfactorily elucidated. Modern theory, while perfectly adequate for all ordinary occasions, shows weaknesses when called on to explain certain pathological conditions, in particular diabetes mellitus. It is true that the present concepts can be twisted and modified to conform to the Procrustean bed of these abnormalities, but the result is not altogether satisfying and there remain one or two hard facts that are resistant to explanation.[...]  Lire la suite

A wet method for the determination of carbon was devised and used to show that total carbon, in a cellulose culture supporting Vibrio perimastix, reached a maximum on the fourth day of incubation at 30° C. The total amino nitrogen content showed a corresponding maximum on the fourth day, suggesting that carbon dioxide assimilation and amino nitrogen formation were linked. Added glutamate supported normal growth in the absence of carbon dioxide, effecting at least a partial substitution for the assimilated gas. Preliminary studies indicated that a pentose-like substance was synthesized during cellulose decomposition and that a fluorescing substance other than …  Lire la suite

Streptomycin was discovered by Schatz, Bugie ana Waksman (1944) in their search for an antibiotic capable of action against grsm-negative bacteria. Since that time, so varied and numerous have been the reports to appear on laboiatory and clinical research on the antibiotic, that a comprehensive survey of the literature has proven to be beyond the scope of this review. Therefore, only those publications having direct bearing upon the problem of the mechanisms of bacterial resistance to streptomycin have here been examined. Brief mention, however, has been made of those surveys in which information on other aspects of the literature on …  Lire la suite

The study of the clay colloids of soils was initiated by Schloesing (46), who in 1870-74, separated, what he termed colloidal clay from French soils. He accomplished this by triturating the soil in the presence of water, decanting the supernatant and then permitting the clay particles to settle out. The material which remained in suspension after 24 hours settling, he designated clay colloid. It comprised 1.5$ of the weight of the whole soil and was thought by Schloesing to be amorphous in nature.[...]  Lire la suite

Tne first, fundamental question asked of the work of an artist is this one -- does he find and collect and comminicate "reality"? And in the quality and sureness of his expressed insight lies his success or failure as an artist. The novel, the most independent, most elastic, most prodigious of literary forms, attains its object in the communication of a full, intense, complex awareness or vision of human life. "II faudrait reconnaitre que l'art du roman est, avant tout, une transpos ition du reel et non une reproduction du reel", states Franeois Mauriac.  Lire la suite

It was felt that a bridge was missing from the family of bridges in the literature dealing with the comparison of capacitance, mutual inductance and/or self inductance. This new bridge would bear a similar relationship to Maxwell Abridge that the Heydweiller did to the Owen. Reference to Appendix I will show these relationships. To keep the study to reasonably comprehensive limits particular attention is to be paid to the comparison of the new bridge with Maxwell's bridge. Frequently the effects of quadrature components of bridge units on the final balance conditions are glossed over in the study of simple bridges …  Lire la suite

Fluid flow has been measured through almost every type of porous material. A considerable portion of these permeability studies has been directed towards the flow of gases through a bed of charcoal grains. The interest in gas flow through charcoal arises from the ability of charcoal to separate one gas from another, and this property has been widely applied both in chemical warfare and industry. It is of fundamental importance to the knowledge of gas flow through a bed of charcoal grains to understand the process by which the sorbable gas is carried into the interior of the charcoal grain. …  Lire la suite

The studies reported in this thesis were undertaken with the principal intent of attempting to evaluate the role of insulin and of the blood sugar level on hydropic degeneration of the islets of Langerhans of rabbits made diabetic by injection of alloxan. It was also hoped that an approach might be made to determining the nature of the hydropic cell. A more remote expectation was that permanent cure or alleviation of the diabetic state might be attained by therapeutic restoration of the islet cells to normal morphological appearance.  Lire la suite