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Studies in the South African Bulbous liliaceae

- Jessop, John Peter

  • Authors: Jessop, John Peter
  • Date: 1973
  • Subjects: Bulbs (Plants) -- South Africa Liliaceae -- South Africa Lilies -- South Africa Liliaceae -- Classification -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4261 , http://hdl.handle.net/10962/d1012563
  • Description: The work comprises two principal sections; an attempt at ellucidating generic relationships in the South African bulbous Liliaceae, and a revision of the species of selected genera. In the first section the approaches investigated were: 1) A re-evaluation of the nature of the bulb apex, showing a likelihood that certain groups possess axillary and other groups terminal inflorescences. 2) An investigation of leaf anatomy, showing that most genera have very similar leaf structure, but that a few genera do differ from this norm. Scilla (Euscilla) generally possesses a distinctly lignified bundle sheath and the Urginea-Drimia group show a great range in structures - including a palisade. 3) An impression technique to determine patterns in the surface of the leaf cuticle. A close correlation appears to exist between these patterns and leaf shape. 4) Scanning Electron Microscope pictures of pollen revealed a considerable uniformity within the group and between this group and most other members of the Liliaceae. 5) Scanning Electron Microscope pictures of seeds revealed two main groups in the bulbous Liliaceae determined on the appearance of the cell walls of the testa. 6) A simple chromatographic technique was not found to be useful. 7) An investigation of chromosome numbers of. 44 samples of 15 species supplemented published data in allowing an analysis to be made of the application of chromosome numbers to generic concepts. Many genera of the Liliaceae - especially in the bulbous group - have extremely variable chromosome numbers. It is considered that numbers are more applicable to tribal than to generic concepts. Few indications of meiotic abnormalities were detected. Phylogenetic and taxonomic aspects of the genera of the bulbous Liliaceae are discussed and a key to the South African bulbous Liliaceae genera constructed. The following generic alterations are proposed: Ledebouria to be split off Scilla. Schizocarphus to be placed in Scilla. Resnova to be placed in Drimiopsis. The Astemme section (= Neobakeria) to be removed from Polyxena and placed in Massonia. The Cape species of Hyacinthus to be placed in Polyxena. Thuranthos, Urgineopsis and Urginea to be placed in Drimia. It is suggested that Schizobasis and Bowiea are of great importance in explaining the origin of Asparagus - possibly even directly from this group. In the generic revisions, thirteen genera are dealt with including typification, synonymy, distribution, field notes, species descriptions and keys. 67 species are dealt with, of which three are new (all in Ledebouria), and 31 new combinations are proposed.
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  • Date Issued: 1973

Studies on the ecology and molecular biology of transferable drug resistance factors in coliform bacteria

- Marcos, David

  • Authors: Marcos, David
  • Date: 1973
  • Subjects: Enterobacteriaceae , Molecular biology , Microbial ecology , Bacteria -- Ecology , Ecology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4249 , http://hdl.handle.net/10962/d1007494 , Enterobacteriaceae , Molecular biology , Microbial ecology , Bacteria -- Ecology , Ecology
  • Description: From Introduction: It was as early as 1904 that Paul Ehrlich propounded the idea of a “magic bullet”. This “magic bullet”, or chemotherapeutic agent, as he also called it, had to meet certain requirements: (a) a high activity against pathogenic micro-organisms; (b) easy absorption by the body; (c) activity in the presence of body fluids and tissue; (d) a low degree of toxicity; (e) must not allow the development of resistant micro-organisms. The discovery of the sulphonamide, Prentosil, by Domagk in 1935 was one of the initial steps in the search for this “magic bullet”. This, together with the production and purification of the antibiotics penicillin, by Fleming, Florey and Chain in 1942 and streptomycin, by Waksman in 1943, heralded a new era in the fight against bacterial infections. The majority of modern antibacterial agents have to a large extent met the requirements of Ehrlich’s ‘magic bullet”. They have however failed to prevent the development of resistant bacterial strains. This has been particularly noticeable in the past twenty years since the sudden emergence of multiple-resistant bacteria, many of which can transfer to several drugs in one step by a process of conjugation. This phenomenon which has serious medical implications has prompted numerous studies on the origin, epidemiology, biochemistry and genetics of transferable drug resistance.
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  • Date Issued: 1973

Taireva

- Mhuri yekwaRwizi, Tracey, Andrew T N, Paul Berliner

The ability of four species of Southern African cichlid fishes to enter deep water

- Caulton, Mark S

  • Authors: Caulton, Mark S
  • Date: 1973
  • Subjects: Cichlids -- Africa, Southern , Tilapia
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5840 , http://hdl.handle.net/10962/d1010429 , Cichlids -- Africa, Southern , Tilapia
  • Description: Using an experimental pressure chamber the rates of descent and the maximum depths of buoyancy equilibrium of some cichlid fishes were tested. Tilapia mossambica juveniles could descend to depths greater than 30 metres very rapidly. At 22°C small sub adult male fish (length ± 160 mm) could descend to a maximum buoyancy depth of 20 metres, small sub adult females to 13 metres while large adults (length ± 200 mm) of both sexes could descend to 11 metres. The fish generally take 4 to 5 days to reach their maximum equilibration depth. At 30°C mature adult male and female T.mossambica increased their maximum equilibration depth to 20 metres and at 15°C showed a decrease to a maximum depth of 6.7 metres. Temperature affects the rates of descent in a similar manner. T.rendalli can descend to 7.5 metres at 22°C. T.sparmanii can descend to 15 metres at 22°C. Hemihaplochromis philander fry and young juveniles are not affected by pressure. Adult males can descend to 16 metres at 22°C and 20 metres at 30°C. Adult females can descend to 26 metres at 22°C and 27 metres at 30°C. In T.mossambica oxygen appears to be the only gas secreted into the swimbladder to compensate for buoyancy loss. The haemoglobin of T.mossambica showed a marked Bohr and Root effect. Increased rates of descent with increased temperature are believed to be due to increased O₂ uptake, heart output etc. rather than as a direct effect of blood chemistry. The swimbladder wall of T.mossambica is extremely thin (2.8 ∕∪ m) and consequently a large amount of gas is lost through passive diffusion. Diffusion is not affected by temperature, consequently the increased secretory rates at higher temperatures are not balanced by a proportionately higher diffusion loss, thus enabling the fish to maintain a deeper buoyancy equilibrium at higher temperatures. Summary, p. 62-63.
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  • Date Issued: 1973

The effects of soil fumigation, applied fertilizers and climate on the growth and nutrient levels of cayenne pineapples under field conditions

- Marr, George Stuart

  • Authors: Marr, George Stuart
  • Date: 1973
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:21067 , http://hdl.handle.net/10962/6246
  • Description: From Introduction: The pineapple producing area of the Eastern Cape lies between 33°S and 34°S latitude. It is the most distant area from the equator in which pineapples are grown commercially, most other areas lying between latitudes 25°N and 25°S (Collins, 1960). The prevailing climatic conditions may be considered as being adverse to the growth of a plant which originated in the tropics. Girton, (1962) considers the area to be unsuitable for commercial production because of the cold weather experienced during winter. Seasonal fluctuations in growth and nutrient levels of the plant have been referred to by van Lelyveld, (1964), but these have never been studied locally. Because of the profound effect of temperature on the growth and nutrient requirements of any plant, it was deemed necessary to investigate the effects of the cooler conditions on the growth and nutrient levels of the pineapple plant, the results of which may give some indications of seasonal nutrient requirements.
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  • Date Issued: 1973

The Hamilton-Jacobi theory in general relativity theory and certain Petrov type D metrics

- Matravers, David Richard

  • Authors: Matravers, David Richard
  • Date: 1973
  • Subjects: Hamilton-Jacobi equations , General relativity (Physics) , Generalized spaces
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5422 , http://hdl.handle.net/10962/d1007551 , Hamilton-Jacobi equations , General relativity (Physics) , Generalized spaces
  • Description: Introduction: The discovery of new solutions to Einstein's field equations has long been a problem in General Relativity. However due to new techniques of Newman and Penrose [1], Carter [2] and others there has been a considerable proliferation of new solutions in recent times. Consequently a new problem has arisen. How are we to interpret the new solutions physically? The tools available, despite a spate of papers in the past fifteen years, remain inadequate although often sophisticated. Any attempts at physical interpretations of metrics are beset with difficulties. There is always the possibility that two entirely different physical pictures will emerge. For example a direct approach would be to attempt an "infilling" of the metric, that is, an extension of the metric into the region occupied by the gravitating matter. However even for the Kerr [1] metric the infilling is by no means unique, in fact a most natural "infilling" turns out to be unphysical (Israel [1]). Yet few people would doubt the physical significance of the Kerr metric. Viewed in this light our attempt to discuss, among other things, the physical interpretation of type D metrics is slightly ambitious. However the problems with regard to this type of metric are not as formidable as for most of the other metrics, since we have been able to integrate the geodesic equations. Nevertheless it is still not possible to produce complete answers to all the questions posed. After a chapter on Mathematical preliminaries the study divides naturally into four sections. We start with an outline of the Hamilton-Jacobi theory of Rund [1] and then go on to show how this theory can be applied to the Carter [2] metrics. In the process we lay a foundation in the calculus of variations for Carter's work. This leads us to the construction of Killing tensors for all but one of the Kinnersley [1] type D vacuum metrics and the Cartei [2] metrics which are not necessarily vacuum metrics. The geodesic equations, for these metrics, are integrated using the Hamilton-Jacobi procedure. The remaining chapters are devoted to the Kinnersley [1] type D vacuum metrics. We omit his class I metrics since these are the Schwarzschild metrics, and have been studied in detail before. Chapter three is devoted to a general study of his class II a metric, a generalisation of the Kerr [1] and NUT (Newman, Tamburino and Unti [1]) metrics. We integrate the geodesic equations and discuss certain general properties: the question of geodesic completeness, the asymptotic properties, and the existence of Killing horizons. Chapter four is concerned with the interpretation of the new parameter 'l', that arises in the class II a and NUT metrics. This parameter was interpreted by Demianski and Newman [1] as a magnetic monopole of mass. Our work centers on the possibility of obtaining observable effects from the presence of 'l'. We have been able to show that its presence is observable, at least in principle, from a study of the motion of particles in the field. In the first place, if l is comparable to the mass of the gravitating system, a comparatively large perihelion shift is to be expected. The possibility of anomalous behaviour in the orbits of test particles, quite unlike anything that occurs in a Newtonian or Schwarzschild field, also arises. In the fifth chapter the Kinnersley class IV metrics are considered. These metrics, which in their simplest form have been known for some time, present serious problems and no interpretations have been suggested. Our discussion is essentially exploratory and the information that does emerge takes the form of suggestions rather than conclusions. Intrinsically the metrics give the impression that interesting results should be obtainable since they are asymptotically flat in certain directions. However the case that we have dealt with does not appear to represent a radiation metric.
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  • Date Issued: 1973

The history, organization and training of wind bands

- Honey, Albert Edward

  • Authors: Honey, Albert Edward
  • Date: 1973
  • Subjects: Band music -- Instruction and study , Band music -- Analysis, appreciation , Bands (Music) -- Instruction and study , Bands (Music)
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:2692 , http://hdl.handle.net/10962/d1013343
  • Description: From introduction: The decision to use the term "Wind Band" in connection with this work was made after much careful deliberation. The English word "Band" is derived from the French "bande" meaning a group of players. It was first applied in this context in England when the Twenty-four Violins at the Court of Charles II (in emulation of "Le Vingt-quatre Violons du Roi at the Court of Louis XIV of France) were known in England as "The King's Band "Band" is a title generally given at the present time to any of instrumentalists, and indeed, many of the World's most famous conductors have been known to refer to any large symphony orchestra as "The Band" and the dressing-room of every Symphony or Concert orchestra in the British Isles is invariably called "The Band-Room"
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  • Date Issued: 1973

The lyric vision of W. H. Davies: pastoral, the unintelligible universe, community

- Rabinowitz, Ivan Arthur

  • Authors: Rabinowitz, Ivan Arthur
  • Date: 1973
  • Subjects: Davies, W. H. (William Henry), 1871-1940 -- Criticism and interpretation , English poetry -- 20th century , Poets, English -- 20th century -- Biography
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2280 , http://hdl.handle.net/10962/d1007579 , Davies, W. H. (William Henry), 1871-1940 -- Criticism and interpretation , English poetry -- 20th century , Poets, English -- 20th century -- Biography
  • Description: From Introductory note: The Complete Poems of W.H. Davies (London: Jonathan Cape, 1963; rev. 1968) has been used throughout this study. Accordingly, unless otherwise stated, all citations of poem numbers and pagination refer to this text. Critical literature on the work of W.H. Davies is restricted in quantity and limited in scope. There are few comprehensive assessments of Davies as poet, autobiographer, novelist, or raconteur. Apart from such sources as Richard J. Stonesifer's full-length critical biography (1963), Lawrence Hockey's biographical monograph (1971), and Thomas Moult's anecdotal and historical appreciation (1934), critical material must be drawn from contemporary reviews, isolated articles in magazines such as The Catholic World and Fortnightly Review, and specific chapters in surveys of the poetry of the early twentieth century, although Davies is frequently alluded to passim in literary histories which deal with this period. Many of these studies favour biographical exposition and evaluation rather than descriptive analysis and discursive interpretation. A detailed chronology of Davies's works is included in Stonesifer's discussion. This thesis is not attempting to trace a line of development for two reasons. First, the Complete Poems gives no indication of date of composition or publication of particular poems, and the present writer has access only to the dates of publication of individual volumes as external evidence of a chronology, internal evidence being confined to such infrequent references as "the birds of steel" in Poem no. 236, p. 260. Secondly, the lyrics themselves do not, on the whole, evince much stylistic and thematic development, and the concern of this study is with recurrent themes and techniques dispersed throughout the oeuvre.
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  • Date Issued: 1973

The nonsense of music

- Mayr, Rupert Eirch

  • Authors: Mayr, Rupert Eirch
  • Date: 1973
  • Subjects: Music -- Philosophy and aesthetics
  • Language: English
  • Type: Text
  • Identifier: vital:652 , http://hdl.handle.net/10962/d1020721
  • Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
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  • Date Issued: 1973

The voice of protest in English poetry : with special reference to poets of the first three decades of the twentieth century

- Verschoor, Edith N E

  • Authors: Verschoor, Edith N E
  • Date: 1973
  • Subjects: Protest poetry, English -- History and criticism , English poetry -- History and criticism , English poetry -- 20th century -- History and criticism
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: vital:2277 , http://hdl.handle.net/10962/d1007270
  • Description: Poetry, like every other form of art, reflects the values of the artist himself as well as the values of the age in which he lives. "I would say that the poet may write about anything provided that the thing matters to him to start with, for then it will bring with it into the poem the intellectual or moral significance which it has for him in life". (Louis MacNeice). This thesis sets out to uncover some of the things which, in the long pageant of English poetry, have "mattered" to poets to such an extent that they have felt compelled to voice their protest against any violation of such things perceived by them in life around them. The basic study has been a search for the different kinds of values and codes of conduct, in social, political and moral spheres, which have been unacceptable to some of the major poets in English, and to examine particularly the manner and the tone of voice in which each one has expressed his disapproval. "Poetry was the mental rattle that awakened the attention of intellect in the infancy of civil society." (T.L.Peacock). English poets who have protested against whatever they regarded as worthy of protest have continued up to the maturity of civil society to be rattles (some soft and mellow, others loud and harsh), to awaken both the intellect and the conscience of their readers.
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  • Date Issued: 1973

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- Performer not specified, Composer not specified, Tracey, Hugh

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