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Scientific research, innovation and economic growth : a possible relationship

- Phillips, Bruce D (Bruce Dalton)

Authors: Phillips, Bruce D (Bruce Dalton)
Date: 1967
Subjects: Research -- Economic aspects , Technological innovations , Research -- South Africa
Language: English
Type: Thesis , Masters , MCom
Identifier: vital:1096 , http://hdl.handle.net/10962/d1013027
Description: Resources devoted to science, or rather to "new science" or research and development and related technical activities have undergone a remarkable rate of increase over the past two decades throughout most of the world. This phenomenon has been symptomatic not only of the development of the majority of nations in the 'western world' but also of the Soviet bloc, and furthermore, all the indications are that this expansion of scientific activities will continue throughout the present decade. Intro., p. 1.
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Date Issued: 1967

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Synthesis of flavan-3, 4-diols, stereochemistry of novel biflavanols and new non-tannins from Acacia Mearnsii

- Saayman, Henry Martin

Authors: Saayman, Henry Martin
Date: 1967
Subjects: Tannins Acacia mearnsii Stereochemistry Wattles (Plants) Chemistry, Analytic
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:4444 , http://hdl.handle.net/10962/d1007704
Description: From Summary: The structural elucidation of condensed tannins, which are considered to consist of C₁₅-flavan units, presents certain difficulties. These tannins occur in extremely complex mixtures, and their isolation is complicated by their susceptibility to oxidative denaturation. Limitations in the formation of significant degradation products add to these problems. Since condensed tannins of black wattle bark yield anthocyanidins on treatment with mineral acids, they are considered to be proanthocyanidin in character. For this reason the initial approach to the investigation of the structures of condensed tannins was by way of the synthesis of novel 7-hydroxyflavan-3,4-diols having a low degree of hydroxyl substitution. Submission of these to modern physical techniques such as nuclear magnetic resonance (n.m.r.) spectroscopy would yield valuable data regarding the chemical shifts and coupling constants of heterocyclic and benzenoid protons which may be used for subsequent work on more highly hydroxylated diols, biflavanols and finally the condensed tannins themselves.
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Date Issued: 1967

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The effect of ultraviolet and gamma irradation on soluble calf-skin collagen

- Davidson, Raymond John

Authors: Davidson, Raymond John
Date: 1967
Subjects: Collagen -- Hide powder Irradiation Solids -- Effect of radiation on Gamma rays -- Dose-response relationship
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:4290 , http://hdl.handle.net/10962/d1003718
Description: Initially the present study was confined to the effects of ultraviolet irradiation on acid-soluble collagen. Such a study was undertaken in order to demonstrate the critical role played by tyrosine and phenylalanine in the intermolecular interaction of the telopeptides protruding from the rigid parent collagen molecule. Since both tyrosine and phenylalanine are photosensitive, and because the collagen telopeptides are relatively rich in these aromatic amino acids, carefully controlled degradation studies involving telopeptide liberation could be made. It became increasingly apparent during the course of investigation, that a better understanding of the subunit composition of thermally denatured acid-soluble collagen was necessary if a satisfactory interpretation of the irradiation studies was to be made. A subsequent study of the subunit composition of thermally denatured acid-soluble collagen resulted in the isolation and characterisation of two major and two minor dimeric components as well as the α- and β - subunits. Three acidic telopeptides and three basic telopeptides were also isolated from acid-soluble collagen during the course of the present study. The presence of the dimeric components while related directly to the method of preparation, suggested that acid-soluble collagen was largely dimeric in nature. Such a conclusion suggested an intermolecular rather than an intraolecular relationship between neutral-salt-soluble and acid-soluble collagen. While it is currently accepted that an intramolecular relationship exists between neutral-salt-soluble and acid-soluble collagen, such a relationship does not satisfactorily explain the very different solubility characteristics displayed by these soluble collagen extracts. With this in mind, and using the study on the subunit composition of thermally denatured acid-soluble collagen as a basis for comparison, the intra and intermolecular relationship between neutral-salt-soluble and acid-soluble collagen was investigated using ultraviolet and gamma irradiation. The effects of ultraviolet and gamma irradiation on soluble collagen preparations proved very similar. Although collagen samples were irradiated in solution from an ultraviolet source; and under anhydrous conditions from a gamma source, much the same degradation mechanism resulted. The initial depolymerisation of dimeric material followed by peptide fission, yielding irradiation-resistant crystalline portions of the parent triple helix, took place in both instances. At the same time, both studies indicated no significant differences in the intra or intermolecular structures of the neutral-salt-soluble and acid-soluble preparations investigated. The dimer content of neutral-salt-soluble collagen preparations was, however, noted to be smaller. To current methods for the preparation of soluble collagens, it may be concluded that such preparations are peptideless to some degree. While the native tropocollagen monomer with its full complement of telopeptide side chains may actively undergo linear polymerisation resulting in fibre formation, the soluble collagen preparations referred to above may only aggregate in a rather random fashion.
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Date Issued: 1967

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The exodus theme in the Old and New Testament

- Sheriffs, Deryck C T

Authors: Sheriffs, Deryck C T
Date: 1967
Subjects: Bible , Exodus, The -- History of doctrines
Language: English
Type: Thesis , Bachelor , BDiv
Identifier: vital:1274 , http://hdl.handle.net/10962/d1013180
Description: The best starting point for an examination of the theme and theology of the Exodus in the Old Testament is the Psalter, for here is recorded the living faith of Israel over a long period. The compilation of the Psalter from its earliest poems to its latest additions and final editing spans several centuries. It is a collection of collections, revised and edited more than once. Most scholars today agree that its material ranges in date from pre-exilic to late post-exilic, there being a swing away from an extravagant preference for a Maccabean dating of many Psalms. The Exodus theme to be found in the Psalter thus falls within a broad historical sweep. In the Psalter, individual and communal expressions of faith both have their place. Personal Psalms lay bare the human heart with the gamut of its emotions from despair to deep joy and praise. Psalms which were used corporately draw together the worshiping community in a way which reveals the unity of Israel, the nation, to be founded upon their relationship to Yahweh. Into the fabric of individual and national life, the thread of the Exodus faith was woven. Our task is to follow this thread, and discover the pattern which it weaves against its background. In the analysis which follows, each of the five Books of the Psalter will be examined in turn, the important passages being dealt with first, then the oblique references to the Exodus, and, lastly, those which may be described as conjectural. There are some nine Psalms which deal directly with the Exodus and the wilderness wanderings ... Chap. 1, p. 1.
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Date Issued: 1967

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The naive moral as a possible mental attitude behind the outlaw-motif in English medieval narratives and its influence upon the structure of Thomas Lodge's "Rosalynde" and Shakespeare's "As you like it"

- Ruthrof, Horst

Authors: Ruthrof, Horst
Date: 1967
Subjects: Literature and morals , English literature -- Middle English, 1100-1500 , English literature -- Early modern, 1500-1700
Language: English
Type: Thesis , Masters , MA
Identifier: vital:2312 , http://hdl.handle.net/10962/d1013105
Description: The idea for this thesis originated in a seminar concerned with short forms of epic literature. It is meant to throw some light on the development of rudimentary narrative technique, especially on the influence a particular motif can exert on a writer's mind and the final form of his work. Preface, p. 7.
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Date Issued: 1967

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The phytochemistry of several South African aloe species

- McCarthy, Terence John

Authors: McCarthy, Terence John
Date: 1967
Subjects: Botanical chemistry Aloe -- Research -- South Africa Aloe -- Analysis Medicinal plants -- Research -- South Africa Drugs -- Research Chromatographic analysis
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:3836 , http://hdl.handle.net/10962/d1007621
Description: Introduction: Despite the tremendous advances made with regard to synthetic organic medicinals within the last two decades, heavy reliance is still placed on plant products. This is especially true of the anthracene derivatives used medicinally as purgatives, and which are derived principally from senna, cascara, rhubarb, frangula and aloes. While particular attention has been paid to the chemistry of the former group in recent years, aloes has been largely neglected, possibly due to the fact that the Aloe species are confined largely to areas where extensive research facilities are lacking, such as Africa , India and the West Indies. Thus research in Europe has been confined largely to the lump aloes of commerce, derived from relatively few species. In 1953 a comprehensive report by Hodge (103) appeared on "The Drug Aloes of Commerce, with Special Reference to the Cape Species". Hodge observed that South Africa abounds in species just as abundant as A.ferox, (which is the prime source of Cape aloes), and advised that a systematic chemical survey might show certain of these to be not only higher yielders of bitter aloetic juice but also sources of a superior drug product. Consequently an investigation along these lines is presented here, and it is observed that several species apart from A.ferox not only contain aloin, but also yield a large volume of aloetic juice. Only pharmacologic studies can reveal if the juice of these species is as safe as that of A.ferox, but without doubt they could be used for the extraction of crystalline aloin. Concurrently, the distribution of the Aloe resins, said by some to be purgative themselves, has been studied. The investigation has revealed that the structurally similar compound homonataloin enjoys an equally wide distribution as aloin. However, almost invariably it is confined to small species yielding little aloetic juice, apart from which nothing is known regarding its pharmacologic properties. It is interesting to note that the resin distribution in the homonataloin-containing species is very similar to that of the aloin-containing species, but differs widely from. that of the species containing neither of these principles. Apart from aloin and homonataloin, aloinoside and chrysophanol also occur in Aloe species, and together with the resins, these indicate that when all the South African Aloe species have been investigated, they may well be of chemotaxonomic value. Within the comparatively short space of the last decade some work has been performed on aspects of the metabolism of such anthracene-containing species as Rheum, Rhamnus and Rumex. These investigations have shown that the anthracene derivatives are not merely waste products, but perform definite metabolic functions. The latter portion of this work has been devoted to this relatively neglected aspect of the Aloe species.
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Date Issued: 1967

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