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Xhosa dance with marimbas

- Marimba Group, Composer Not Specified, Dargie, Dave

The petrology, mineralogy and geochemistry of the main zone of the Bushveld Complex at Rustenburg Platinum Mines, Union Section

- Mitchell, Andrew Alexander

  • Authors: Mitchell, Andrew Alexander
  • Date: 1988
  • Subjects: Mineralogy -- South Africa Petrology -- South Africa Rustenburg Platinum Mines Geochemistry -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:4903 , http://hdl.handle.net/10962/d1001563
  • Description: Union Section of Rustenburg Patinum Mines is situated in the northwestern part of the Bushveld Complex, some twenty kilometres north of the Pilanesberg Alkaline Complex. The mining lease area covers a roughly triangular segment of Lower, Critical and Main Zone rocks, transgressed to the north and south by magnetite-bearing ferrogabbro of the Upper Zone. The Main Zone at Union Section is the focus of this study. The prime source of sample material for the study is the deep exploration borehole SK2, but additional, supplementary samples were collected on surface and underground, as well as from a second surface exploration borehole, SK4. In line with the recommendations of SACS (1980), the top of the Critical Zone, and therefore the base of the Main Zone, is taken to be the top of the Bastard Cyclic Unit. Sharpe (1985) suggested that the succession from the base of the Main is an isotopically separate entity Zone up to the Pyroxenite Marker from the rest of the Bushveld layered succession. This is not strictly true, as there is evidence that more than one parental magma was involved in the formation of this interval. It is, however, true that there are fundamental differences, particularly in isotopic makeup, between the Main Zone rocks below the pyroxenite Marker and those above (the latter having been assigned by Molyneux (1970) to subzone C of the Main Zone). Kruger et al. (1986, in press) suggested that the Pyroxenite Marker marks the base of the Upper Zone, and this convention is adhered to here. The implication of this is that the rocks which formerly constituted subzone C of the Main Zone are now considered part of the Upper Zone. The Main Zone rocks below the pyroxenite Marker were originally subdivided by Molyneux (1970) into two subzones, A and B. The results of the present study indicate that this subdivision is not justified. Instead, eight units have been distinguished in the Main Zone on geochemical, petrological and mineralogical bases. Each of these units is characterized by a coherent set, or progression, of chemical and petrological characteristics. The specific assignment of genetic connotations to these units has been deliberately avoided , at least until further studies of the Main Zone prove this to be justified. The demarcation of the eight units is illustrated in the composite diagram (Fig. 34) in the back pocket of this work, and the reasons for the subdivisions are listed in Table 6 (at the end of chapter 7 of this thesis). Until the late 1970's, it was thought that most layered cumulates formed by crystal settling (Wager and Brown, 1968). More recently, there has been a fundamental conceptual change, and many workers now believe that most cumulate rocks formed by in situ crystallization at the floor and walls of the magma chamber (McBirney and Noyes, 1979, Irvine, 1980a; Campbell, 1987). There is, however, some evidence for the physical separation of phases undergoing cotectic crystallization, particularly in the Upper Critical Zone and lower part of the Main Zone (Eales et al., 1986). This process, which has been alluded to in the past by various authors (Ferguson and Botha, 1963; Vermaak, 1976) involves the flotation of early-formed plagioclase crystals due to their positive bouyancy in tholeiitic liquids. The result is an apparent decoupling of the chemistry of pyroxene and plagioclase, as in unit IV of the Main Zone, where plagioclase becomes more anorthitic upwards, whilst pyroxene becomes more iron-rich. There is some substantial evidence, particularly in reversals in the strontium isotope initial ratio and the orthopyroxene Mg/(Mg+Fe) ratio , for multiple intrusion in the Main Zone. Although the largest and most important magma influx in the Main Zone was a high-R₀ aluminous tholeiite, as suggested by Sharpe (1985), the intrusive history of the Main Zone is believed to be far more complex than Sharpe (op. cit.) suggested. Significantly, there is strong evidence for small influxes of Upper Zone-type (Fe-rich tholeiite) magma in the upper reaches of the Main Zone. These are believed to be precursors to the major influx of Upper Zone-type magma at the pyroxenite Marker (Kruger et al, 1986, in press). The fate of intercumulus liquids in cumulate rocks has recently recieved substantial attention (Sparks et al., 1985; Morse, 1986; Barnes, 1986: Campbell, 1987). It is believed that the migration, or at least redistribution, of intercumulus liquids has played a vital role in modifying fractionation trends in the Main Zone. More importantly, the accumulation of late-stage intercumulus liquids is believed to be responsible for the formation of the Fe-rich ultramafic pegmatite bodies that interrupt the layered cumulates in borehole SK2 , Adobe Acrobat 9.53 Paper Capture Plug-in
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  • Date Issued: 1988

Ungumpriste

- St Mary's Congregation, Marimba Group, Composer Not Specified, Dargie, Dave

Yuvitenu livangeli

- Nangura, Cecilia, Ruhepo, Serafina, School Choir, Gregensia, Sister, Composer not specified, Dargie, Dave

Gho Nyambi

- Group of Locals, Composer Not Specified, Dargie, Dave

Zwothe Zwothe

- Group of Church Singers, Composer Not Specified, Dargie, Dave

Ngiyakholwa

- Ga-Rankuwa Marimba Group, Composer Not Specified, Dargie, Dave

Application of high-performance liquid chromatography to the analysis, stability and pharmacokinetics of erythromycin

- Stubbs, Christopher

  • Authors: Stubbs, Christopher
  • Date: 1988
  • Subjects: Erythromycin High performance liquid chromatography
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:3809 , http://hdl.handle.net/10962/d1004372
  • Description: Erythromycin is a macrolide antibiotic used mainly in the treatment of infections caused by gram-positive organisms. Erythromycin base is rap idly degraded in acidic media necessitating the use of structurally modified erythromycin derivatives or acid resistant dosage forms in order to decrease gastric inactivation of the drug. The majority of pharmacokinetic studies to-date have utilized relatively non-specific microbiological assay procedures which are unable to differentiate between concentrations of active erythromycin base and the inactive pro-drug derivatives. A high-performance liquid chromatographic (HPLC) technique is described for the simultaneous determination of erythromycin base and propionate (inactive pro-drug form) in human serum and urine following the oral administration of erythromycin estolate, an acid stable derivative of erythromycin. The method involves a solid-phase extraction step prior to chromatography on a C18 reversed-phase column with coulometric electrochemical detection. Sample handling and storage techniques are presented which minimize hydrolysis of the inactive ester moiety between sample collection and analysis, thereby more accurately reflecting the in vivo situation than in previously published studies. Results from single dose pharmacokinetic studies indicate that only 10-15% of the total erythromycin concentration in vivo is present as the active base component following oral administration of erythromycin estolate. This percentage increases to approximately 25% during multiple dose administration. Novel urinary excretion data are presented which reveal that approximately 40% and 55% of the total erythromycin excreted in urine is excreted as erythromycin base following single and multiple dosages respectively. Computer fitting of mean serum concentration-time data revealed that an open one compartment model with linear first order absorption and elimination best described the absorption and disposition of erythromycin, although poor computer fits for individual data sets were observed. Some evidence of non-linear elimination is presented utilizing both compartmental and non-compartmental pharmacokinetic techniques. Large intra-and inter-personal variability in erythromycin absorption and disposition was experienced which was evaluated in five subjects who each received one 500 mg erythromycin estolate tablet from the same batch, on three separate occasions. In addition. an HPLC method is described for the analysis of "total erythromycin" concentrations following erythromycin estolate administration which involves hydrolysis of the ester component prior to chromatography. as well as an HPLC method utilizing amperometric electrochemical detection capable of monitoring the stability of erythromycin base in stored biological fluids. These methods were uti I ized in various stability studies involving erythromycin base and propionate as well as for the analysis of erythromycin estolate dosage forms.
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  • Date Issued: 1988

A phenomenological explication of the artistic creative experience of a painter, a writer and a playwright

- Lambie, Eileen

  • Authors: Lambie, Eileen
  • Date: 1988
  • Subjects: Phenomenology Art -- Philosophy Artists Creation (Literary, artistic, etc.)
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3115 , http://hdl.handle.net/10962/d1004605
  • Description: The aim of the thesis was to explore two focus questions using the phenomenological approach. Firstly, what it meant to be an artist for three particular artists; a painter, a writer and a playwright. Secondly, what a general explicitation (after Van Kaam, 1958) of the three subjects' artistic creative experience and working processes revealed in essence. The taped data of the three artists were reduced and explored through a number of phenomenological strategies. This led to the formulation of four essential descriptions for each artist, which were based structurally on Van den Berg's experiential categories in A Different Existence. Thus, the essential descriptions reflect each artist's relationship with his/her world, body, fellow people and time. The final step was the achievement of a general extended description. The major conclusion arising from the phenomenological explication is that art affords a way through which artists are able to live an authentic existence. That is, the body and world of the artist are in harmony and the artist's art roots him in the past, is manifest in the present and indicates the future direction of his work. Another conclusion is that the artist is Janus-faced and this enables him/her to balance subjectivity and objectivity in the Lebenswelt and to communicate what he/she sees to others in a healthy way through art. The artist's relationship with world, body, fellow people and with time, is postulated as being qualitatively richer than that of the nonartist. The two focus questions were successfully answered through the research explication and were validated by two independent judges. The viability of the phenomenological approach in the field of artistic creativity was therefore demonstrated. Suggestions for future research were made, one of which was that more phenomenological research aimed at eliciting specific information on the creation of art works might render more information on the artistic creative process.
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  • Date Issued: 1988

Defined by wine : a study of sacramentalism in George Herbertʾs poetry

- Goddard, Kevin Graham

  • Authors: Goddard, Kevin Graham
  • Date: 1988
  • Subjects: Herbert, George, 1593-1633 -- Criticism and interpretation , Christian poetry, English -- History and criticism
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: vital:2177 , http://hdl.handle.net/10962/d1001828
  • Description: This dissertation proposes that George Herbertʾs poetry may profitably be understood as a sacramental means by which the divine is made present in temporal existence. In order to support this claim, the relation between sacramental symbolism and literary symbolism, particularly Herbertʾs, is examined from a number of perspectives. The symbolic meanings suggested by Herbertʾs title (The Temple), and their relation to sacramentalism are considered in the opening chapter. This includes a consideration of some of the background to the analogical thinking prevalent in both the seventeenth-century and Herbert. It is followed in the second chapter by an examination of some of the modern theories about how literary symbolism may relate to sacramental symbolism, a discussion which is followed by a consideration of this dissertation's argument in relation to modern scholarship. The chapter ends with a reading of ʺThe Flowerʺ. The third chapter discusses the poet's attempt to imitate the divine by ʺcopyingʺ both Scripture and Nature, and this includes a consideration of the allegorical and hieroglyphic modes of thought prevalent in the poems. The concern with imitation encourages an examination of the poet's frequent invitation for God actually to assume the poet's role, and this is the subject of the fourth chapter. The argument suggests that the poet's attempt to ʺsacrificeʺ his own writing may be seen in his concern with corporate imagery and corporate (impersonal) structures. The five ʺAfflictionʺ poems are examined as examples of the first, while structures such as synecdoche and metonymy are examined as examples of the second. The final chapter considers aspects of narrative time in the poems, particularly the sense often evoked of the eternal being imminent in the present. This involves a consideration of both liturgical imagery, and what may be called liturgical structures as they can be seen to operate in the poems. Particular examples of the latter are the relation between the liturgical anamnesis and the poems, as well as certain narrative structures that may be called ʺachronisticʺ.
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  • Date Issued: 1988

Petrology and geochemistry of the lower group chromitites and host rocks on the farm Zandspruit 168 JP, Western Bushveld Complex

- Botha, Michael James

  • Authors: Botha, Michael James
  • Date: 1988
  • Subjects: Petrology -- Africa, Southern , Geochemistry
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4905 , http://hdl.handle.net/10962/d1001565
  • Description: The eight Lower Group chromitite layers of the Ruighoek Pyroxenite in the area west of the Pilanesberg (LGl - LG7), on the farm Zandspruit 168 JP, were sampled in borehole cores drilled through the succession. The stratigraphic succession faIls within Cameron's (980) units B to E of the Critical Zone. The lowermost layer of the Lower Group, the LG 1 chromitite, is located some 440 metres below the MG 2 (Middle Group) chromitite layer, above which the first appearance of cumulus plagioclase in the Complex is seen. By convention, this horizon is designated the top of the Ruighoek Pyroxenite in the Western Bushveld Complex. Homogeneous units of chromite-bearing orthopyroxenite (bronzitite), exhibiting inconspicuous layering defined in terms of variations in orthopyroxene grain-size host all but one of the Lower Group layers; the LG 4 chromitite layer is exposed within an olivine-rich subunit 23 metres in thickness (C₃ subunit). The cumulative thickness of chromitite is 2,92 metres or 0,8 per cent of the studied section, which is 381 metres in thickness. Minimum and maximum thicknesses of the LGl - LG7 layers exposed in drill core are 17 and 81 centimetres, respectively, with minor chromitite layers ranging between 2 and 5 centimetres in thickness. Weighted mean Cr₂0₃ contents of units B to E vary between 1,17 and 3,22 per cent, with the latter estimate representative of the D₂ subunit which hosts the LG 6 chromitite layer. The LG 6 is correlated with the Steelpoort layer of the Eastern Bushveld Complex, and varies between 76 and 81 centimetres in thickness under a large portion of the farm Zandspruit. An undisturbed succession striking N15°E and dipping 12 - 15°E is depicted within the studied area, which is bounded on the eastern side by the north-striking Frank fault. Major folding of the layered succession is evident to the north of the area, where the layering adjacent to the trace of the fault dips 35° to the southwest. Particular attention is paid in the present study to (a) the nature of chromitite layers and their host rocks, (b) the contrast between the mineral chemistry of weakly disseminated chromite and grains within massive ore layers, (c) concentrations of Cr, V, Ni, Co, Sc and Ti in orthopyroxene in relation to stratigraphic height, and levels of Sr, Ba and Zr associated with hypothetically pure, intercumulus plagioclase feldspar, and (d) possible mechanisms which induce crystallization of chromitite layers containing 50 per cent Cr₂0₃ from magma with a Cr content of less than 1 000 ppm. Electron microprobe studies of chromite in relation to mineralogical and textural environment clearly reveal that (a) the proportions of Cr and Al cations are linked to paragenesis: higher Al/Cr ratios characterize olivine-bearing domains, whereas grains intergrown with plagioclase feldspar exhibit low AI/Cr ratios, and (b) Al contents rise with a decline in Mg/(Mg + Fe²⁺) from high values to a value of 0,450, then decrease with a further decline in Mg/(Mg + Fe²⁺). The paragenetically later trend is emphasized in a large population of chromite grains which escaped early encapsulation in orthopyroxene crystals and continued to grow in the environment of intercumulus plagioclase. Within-and between-sample compositional variation of grains in silicate-rich domains is modelled in terms of in situ growth increments, diffusive homogenization of zonal structures, and residence time within interstitial melt. Fractionation trends, as measured by Mg/(Mg + Fe²⁺) ratios in whole-rock and/or microprobe studies of orthopyroxene, are reversed in relation to stratigraphic height towards the top of the B unit and in the overlying C unit. These data are supported, for example, by lower vanadium contents and higher Ni/Sc ratios in hypothetically pure orthopyroxene. Small olivine crystals in chromite-rich domains are enriched in Ni relative to coarse-grained olivine in adjacent dunite: a feature attributed to early isolation of primocrysts from magma in the former case, and in situ equilibration between olivine crystals and Ni-depleted residual melt in the latter case . Similarly, rising Ni contents and Mg/(Mg + Fe²⁺) ratios of orthopyroxene with increasing stratigraphic height in the footwall of the LG 6 chromitite layer, linked to a progressive decline in orthopyroxene grain-size, are effects which may arise out of early separation of interstitial melt from orthopyroxene cumulates. A model is thus proposed which (a) links the thickness of chromitite layers to the vertical separation between successive layers or the thickness of fine-grained orthopyroxenite in the footwall, (b) ascribes copious nucleation of chromite to liquid mixing of this footwall derived, Cr - depleted contaminant with influxes of hot, primitive magma, and (c) tenders the notion that the present modal proportion of mesostasis in the footwall of a chromitite layer serves as a reciprocal measure of the volume of fractionated exudate
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  • Date Issued: 1988

A study of universal algebras in fuzzy set theory

- Murali, V

  • Authors: Murali, V
  • Date: 1988
  • Subjects: Fuzzy sets Algebra, Universal
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5394 , http://hdl.handle.net/10962/d1001983
  • Description: This thesis attempts a synthesis of two important and fast developing branches of mathematics, namely universal algebra and fuzzy set theory. Given an abstract algebra [X,F] where X is a non-empty set and F is a set of finitary operations on X, a fuzzy algebra [I×,F] is constructed by extending operations on X to that on I×, the set of fuzzy subsets of X (I denotes the unit interval), using Zadeh's extension principle. Homomorphisms between fuzzy algebras are defined and discussed. Fuzzy subalgebras of an algebra are defined to be elements of a fuzzy algebra which respect the extended algebra operations under inclusion of fuzzy subsets. The family of fuzzy subalgebras of an algebra is an algebraic closure system in I×. Thus the set of fuzzy subalgebras is a complete lattice. A fuzzy equivalence relation on a set is defined and a partition of such a relation into a class of fuzzy subsets is derived. Using these ideas, fuzzy functions between sets, fuzzy congruence relations, and fuzzy homomorphisms are defined. The kernels of fuzzy homomorphisms are proved to be fuzzy congruence relations, paving the way for the fuzzy isomorphism theorem. Finally, we sketch some ideas on free fuzzy subalgebras and polynomial algebras. In a nutshell, we can say that this thesis treats the central ideas of universal algebras, namely subalgebras, homomorphisms, equivalence and congruence relations, isomorphism theorems and free algebra in the fuzzy set theory setting
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  • Date Issued: 1988

Unmelwana wakho

- St Mary's Congregation, Marimba Group, Composer Not Specified, Dargie, Dave

Bawo usikhulule

- St Mary's Congregation, Marimba Group, Composer Not Specified, Dargie, Dave

Katanda

- Rukunde, Diomeda, Group of Women, Composer Not Specified, Dargie, Dave

Etlang Kamoka le utlwe

- Pedi Workshop Group, Composer Not Specified, Dargie, Dave

Ntsikana's Great Hymn

- Marimba Group, Composer Not Specified, Dargie, Dave

Ntsikana's Great Hymn

- Marimba Group, Composer Not Specified, Dargie, Dave

Nkosi sikilela iAfrika

- St John Vianney Seminary Congregation, Composer not specified, Dargie, Dave, Huwiler, Kurt

Nkosi sikilela iAfrika

- St John Vianney Seminary Congregation, Composer not specified, Dargie, Dave, Huwiler, Kurt

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