Aspects of the bioavailability of topical corticosteroid formulations
- Authors: Magnus, Ashley Denis
- Date: 2013-02-12
- Subjects: Adrenocortical hormones -- Therapeutic use , Dermatologic agents , Transdermal medication -- Evaluation , Dermatopharmacology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3843 , http://hdl.handle.net/10962/d1009516 , Adrenocortical hormones -- Therapeutic use , Dermatologic agents , Transdermal medication -- Evaluation , Dermatopharmacology
- Description: Two possible variables of the McKenzie/Stoughton blanching assay, namely amount applied to the test site and occlusion time have been investigated. Subsequently, two topical steroid preparations, Synalar cream (0,025% fluocinolone acetonide) and Betnovate cream (0,1% betamethasone 17-valer ate) were extemporaneously diluted with five and six placebo bases respectively. Taking cognizance of the two possible variables, these diluted preparations were assessed in vivo using a modified version of the McKenzie/Stoughton blanching assay for blanching activity over a 14 month period. It was found that the base E45, which is slightly alkali, had the greatest effect on both preparations. In the case of betamethasone 17-valerate this base c aused the conversion to the less active isomer, betamethasone 21-valerate whereas at the end of the 14 month test period it was found that the Synalar/E45 dilution contained no fluocinolone acetonide. Quantitative analysis of all the diluted preparations by high performance liquid chromatography using a reverse-phase system was performed. The data obtained f r om the systematic stUdies of the effects of varying concentrations and occlusion times were presented at the Eleventh National Congress of the South African Pharmacological Society. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Authors: Magnus, Ashley Denis
- Date: 2013-02-12
- Subjects: Adrenocortical hormones -- Therapeutic use , Dermatologic agents , Transdermal medication -- Evaluation , Dermatopharmacology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3843 , http://hdl.handle.net/10962/d1009516 , Adrenocortical hormones -- Therapeutic use , Dermatologic agents , Transdermal medication -- Evaluation , Dermatopharmacology
- Description: Two possible variables of the McKenzie/Stoughton blanching assay, namely amount applied to the test site and occlusion time have been investigated. Subsequently, two topical steroid preparations, Synalar cream (0,025% fluocinolone acetonide) and Betnovate cream (0,1% betamethasone 17-valer ate) were extemporaneously diluted with five and six placebo bases respectively. Taking cognizance of the two possible variables, these diluted preparations were assessed in vivo using a modified version of the McKenzie/Stoughton blanching assay for blanching activity over a 14 month period. It was found that the base E45, which is slightly alkali, had the greatest effect on both preparations. In the case of betamethasone 17-valerate this base c aused the conversion to the less active isomer, betamethasone 21-valerate whereas at the end of the 14 month test period it was found that the Synalar/E45 dilution contained no fluocinolone acetonide. Quantitative analysis of all the diluted preparations by high performance liquid chromatography using a reverse-phase system was performed. The data obtained f r om the systematic stUdies of the effects of varying concentrations and occlusion times were presented at the Eleventh National Congress of the South African Pharmacological Society. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
Simochromis margaretae, a new species of cichlid fish from Lake Tanganyika
- Axelrod, G S (Glen S.), Harrison, J A (James A.), Rhodes University. J.L.B. Smith Institute of Ichthyology
- Authors: Axelrod, G S (Glen S.) , Harrison, J A (James A.) , Rhodes University. J.L.B. Smith Institute of Ichthyology
- Date: 1978-12
- Subjects: Simochromis margaretae , Simochromis -- Classification , Fishes -- Classification , Fishes -- Tanganyika, Lake
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69825 , vital:29585 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 19 , A new cichlid species of the endemic Lake Tanganyikan genus Simochromis is described from four specimens from Kigoma Harbour, illustrated and compared with the other five species of the genus. The new species, S. margaretae, differs from the others in having a greater caudal peduncle depth, longer anal fin spines, and a narrower mouth. The new species further differs from its closest relative, S. marginatus, in having a greater interorbital width, greater postocular head portion, longer mouth, and shorter pectoral fin.
- Full Text:
- Date Issued: 1978-12
- Authors: Axelrod, G S (Glen S.) , Harrison, J A (James A.) , Rhodes University. J.L.B. Smith Institute of Ichthyology
- Date: 1978-12
- Subjects: Simochromis margaretae , Simochromis -- Classification , Fishes -- Classification , Fishes -- Tanganyika, Lake
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69825 , vital:29585 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 19 , A new cichlid species of the endemic Lake Tanganyikan genus Simochromis is described from four specimens from Kigoma Harbour, illustrated and compared with the other five species of the genus. The new species, S. margaretae, differs from the others in having a greater caudal peduncle depth, longer anal fin spines, and a narrower mouth. The new species further differs from its closest relative, S. marginatus, in having a greater interorbital width, greater postocular head portion, longer mouth, and shorter pectoral fin.
- Full Text:
- Date Issued: 1978-12
Pavoclinus myae, a new species of clinid fish (Perciformes Blennoidei) from South Africa, with a note on the identity of P. graminis and P. laurentii, and a key to the known species of Pavoclinus
- Christensen, M S (Makkel Skou), Rhodes University. J.L.B. Smith Institute of Ichthyology
- Authors: Christensen, M S (Makkel Skou) , Rhodes University. J.L.B. Smith Institute of Ichthyology
- Date: 1978-07
- Subjects: Pavoclinus -- Identification , Pavoclinus myae -- Classification , Fishes -- Classification , Fishes -- South Africa -- Classification
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69814 , vital:29584 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 18 , Pavoclinus myae n.sp. is described from seven specimens collected off the eastern Cape Province, South Africa. The combination of a separate and high anterior section of the dorsal fin, a narrow caudal peduncle, vomerine teeth and fin counts separates P. myae from the eight other members of the genus. The validity of Pavoclinus graminis and P. laurentii was examined and confirmed. New distinguishing features were found, as characters previously used to differentiate these two species were unreliable.
- Full Text:
- Date Issued: 1978-07
- Authors: Christensen, M S (Makkel Skou) , Rhodes University. J.L.B. Smith Institute of Ichthyology
- Date: 1978-07
- Subjects: Pavoclinus -- Identification , Pavoclinus myae -- Classification , Fishes -- Classification , Fishes -- South Africa -- Classification
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/69814 , vital:29584 , Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB)) Periodicals Margaret Smith Library (South African Institute for Aquatic Biodiversity (SAIAB))
- Description: Online version of original print edition of the Special Publication of the J.L.B. Smith Institute of Ichthyology; No. 18 , Pavoclinus myae n.sp. is described from seven specimens collected off the eastern Cape Province, South Africa. The combination of a separate and high anterior section of the dorsal fin, a narrow caudal peduncle, vomerine teeth and fin counts separates P. myae from the eight other members of the genus. The validity of Pavoclinus graminis and P. laurentii was examined and confirmed. New distinguishing features were found, as characters previously used to differentiate these two species were unreliable.
- Full Text:
- Date Issued: 1978-07
A contribution to a generic revision of Simochromis and Tropheus (Pisces : Cichlidae) - from Lake Tanganyika, with special reference to the Pharyngeal Apophysis and its taxonomic importance
- Authors: Axelrod, Glen S
- Date: 1978
- Subjects: Cichlids -- Tanganyika, Lake
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5349 , http://hdl.handle.net/10962/d1007510 , Cichlids -- Tanganyika, Lake
- Description: The purpose of this thesis is to investigate the taxonomic status of Simochromis and Tropheue. Material for the study wae collected during three visits to Lake Tanganyika in 1976-1977. Tropheus polli G. S . Axelrod 1977, was found and described, and a new species of Simochromis was found and will be described in a forthcoming paper. Nine colour varieties of Tropheus maorii and three colour varieties of Tropheus duboisi were found and described. A diagnosis and description, with colour photographs, is given using morphometries and meristics of the five species of Simochromis and four species of Tropheus. A dissection and cleaning technique tor the pharyngeal apophysis and lower pharyngeal bone is explained, together with a method for the interpretation of relative bone composition of the pharyngeal apophysis. Photographs are included. The dentition is examined, evaluated and figured. Doubt has been cast upon the taxonomic validity of the composition of the pharyngeal apophysis as an indicator of affinity at the sub familial level. This is shown by its seeming lack of functional relationship, apparent arbitrary variation, interspecific variability in Simochromis and Tropheus, and intraspecific variability in S. diagramma and T. duboisi. Thus, the apophysis cannot be considered a reliable cichlid taxonomic characteristic at any level of classification, unless its validity is Substantiated in each instance. Furthermore, it is considered very probable that the Tropheus-Simochromis species complex is a monophyletic assemblage at the genus level, on the basis of similar dentition and mouth form, which is unique in Lake Tanganyika. It is proposed on phyletic grounds that Simochromis and Tropheus be united into the one genus Tropheus, and that Tropheus be divided into the subgenera , Tropheus (Tropheus) and Tropheus (Simochromis), along the lines of its previous division in two separate genera. Characteristics supporting this division include differences in the anal and dorsal fin meristic counts noted in the original descriptions of the genera. In addition, two modifications of the dentition were found during the course of this study which are not mentioned in any previous literature. It is considered probable, that Tropheus (Tropheus) and Tropheus (Simochromis) are monophyletic sister groups within the Tropheus complex. Pseudosimochromis Nelissen 1977 is not considered to be a taxonomically valid genus on either phyletic or gradistic grounds, and is included within Tropheus (Simochromis). The lower pharyngeal bone of T . (S.) diagramma is considered to be plesiomorphic in tooth arrangement, size and shape. A preliminary worKing hypothesis is established on the basis of the conjectures made and other available information which supports the phyletic relationship suggested by Fryer and lIes (1972). An illustration is given.
- Full Text:
- Date Issued: 1978
- Authors: Axelrod, Glen S
- Date: 1978
- Subjects: Cichlids -- Tanganyika, Lake
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5349 , http://hdl.handle.net/10962/d1007510 , Cichlids -- Tanganyika, Lake
- Description: The purpose of this thesis is to investigate the taxonomic status of Simochromis and Tropheue. Material for the study wae collected during three visits to Lake Tanganyika in 1976-1977. Tropheus polli G. S . Axelrod 1977, was found and described, and a new species of Simochromis was found and will be described in a forthcoming paper. Nine colour varieties of Tropheus maorii and three colour varieties of Tropheus duboisi were found and described. A diagnosis and description, with colour photographs, is given using morphometries and meristics of the five species of Simochromis and four species of Tropheus. A dissection and cleaning technique tor the pharyngeal apophysis and lower pharyngeal bone is explained, together with a method for the interpretation of relative bone composition of the pharyngeal apophysis. Photographs are included. The dentition is examined, evaluated and figured. Doubt has been cast upon the taxonomic validity of the composition of the pharyngeal apophysis as an indicator of affinity at the sub familial level. This is shown by its seeming lack of functional relationship, apparent arbitrary variation, interspecific variability in Simochromis and Tropheus, and intraspecific variability in S. diagramma and T. duboisi. Thus, the apophysis cannot be considered a reliable cichlid taxonomic characteristic at any level of classification, unless its validity is Substantiated in each instance. Furthermore, it is considered very probable that the Tropheus-Simochromis species complex is a monophyletic assemblage at the genus level, on the basis of similar dentition and mouth form, which is unique in Lake Tanganyika. It is proposed on phyletic grounds that Simochromis and Tropheus be united into the one genus Tropheus, and that Tropheus be divided into the subgenera , Tropheus (Tropheus) and Tropheus (Simochromis), along the lines of its previous division in two separate genera. Characteristics supporting this division include differences in the anal and dorsal fin meristic counts noted in the original descriptions of the genera. In addition, two modifications of the dentition were found during the course of this study which are not mentioned in any previous literature. It is considered probable, that Tropheus (Tropheus) and Tropheus (Simochromis) are monophyletic sister groups within the Tropheus complex. Pseudosimochromis Nelissen 1977 is not considered to be a taxonomically valid genus on either phyletic or gradistic grounds, and is included within Tropheus (Simochromis). The lower pharyngeal bone of T . (S.) diagramma is considered to be plesiomorphic in tooth arrangement, size and shape. A preliminary worKing hypothesis is established on the basis of the conjectures made and other available information which supports the phyletic relationship suggested by Fryer and lIes (1972). An illustration is given.
- Full Text:
- Date Issued: 1978
A contribution to the petrology of kimberlites
- Authors: Kruger, Floris Johan
- Date: 1978 , 2013-10-17
- Subjects: Kimberlite -- Africa, Southern , Petrology , Igneous rocks -- Inclusions
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5024 , http://hdl.handle.net/10962/d1006886 , Kimberlite -- Africa, Southern , Petrology , Igneous rocks -- Inclusions
- Description: The petrogenetic relationships of the different varieties of kimberlite in the De Beers Mine and Letseng-Ia-terai composite diatremes have been investigated using petrographic and chemical methods. Kimberlites in the Letseng-Ia-terai diatreme were found to be strongly contaminated by crustal material, mainly basalt. A method to correct for the effects of the contamination has been developed and applied to these kimberlites. Using the corrected data, the four kimberlite types in each group appear to be related to each other by crystal/liquid fractionation models. However the two groups cannot be related to each other. The De Beer Mine has two varieties of kimberlite, a monticellite apatite and calcite rich variety which intruded first, and a phlogopite rich type forming a discrete cylindrical body within the earlier kimberlite. These two kimberlites do not appear to be related by any of the fractionation models discussed. An examination of the data from this work and published sources, suggests that kimberlites are derived from below the low velocity zone by small degrees of partial melting involving garnet lherzolite with subordinate phlogopite and carbonate. Diamonds are probably incorporated as xenocrysts in the magma. Upward movement and emplacement of kimberlite appears to have been very rapid. The diatremes were probably eroded and shaped by gas, derived from the kimberlite magma, escaping to surface along weak zones in the earth's crust. Xenoliths of crustal material incorporated in the kimberlite on intrusion have also been studied and various features due to alteration by the magma are described, including the formation of natrolite and cebollite. The latter is a rare mineral that has not been described from kimberlite before. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 1978
- Authors: Kruger, Floris Johan
- Date: 1978 , 2013-10-17
- Subjects: Kimberlite -- Africa, Southern , Petrology , Igneous rocks -- Inclusions
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5024 , http://hdl.handle.net/10962/d1006886 , Kimberlite -- Africa, Southern , Petrology , Igneous rocks -- Inclusions
- Description: The petrogenetic relationships of the different varieties of kimberlite in the De Beers Mine and Letseng-Ia-terai composite diatremes have been investigated using petrographic and chemical methods. Kimberlites in the Letseng-Ia-terai diatreme were found to be strongly contaminated by crustal material, mainly basalt. A method to correct for the effects of the contamination has been developed and applied to these kimberlites. Using the corrected data, the four kimberlite types in each group appear to be related to each other by crystal/liquid fractionation models. However the two groups cannot be related to each other. The De Beer Mine has two varieties of kimberlite, a monticellite apatite and calcite rich variety which intruded first, and a phlogopite rich type forming a discrete cylindrical body within the earlier kimberlite. These two kimberlites do not appear to be related by any of the fractionation models discussed. An examination of the data from this work and published sources, suggests that kimberlites are derived from below the low velocity zone by small degrees of partial melting involving garnet lherzolite with subordinate phlogopite and carbonate. Diamonds are probably incorporated as xenocrysts in the magma. Upward movement and emplacement of kimberlite appears to have been very rapid. The diatremes were probably eroded and shaped by gas, derived from the kimberlite magma, escaping to surface along weak zones in the earth's crust. Xenoliths of crustal material incorporated in the kimberlite on intrusion have also been studied and various features due to alteration by the magma are described, including the formation of natrolite and cebollite. The latter is a rare mineral that has not been described from kimberlite before. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 1978
A taxonomic study of the Genus Lethrinops Regan (Pisces: Cichlidae) from Lake Malawi: part 2
- Eccles, David H, Lewis, Digby S C
- Authors: Eccles, David H , Lewis, Digby S C
- Date: 1978
- Subjects: Lethrinops -- Malawi, Lake -- Classification , Haplochromis -- Malawi, Lake -- Classification
- Language: English
- Type: Text
- Identifier: vital:14989 , http://hdl.handle.net/10962/d1018957 , ISBN 094998096x , Ichthyological Bulletin of the J.L.B. Smith Institute of Ichthyology; No. 37
- Description: Lethrinops argentea Ahl, L. lethrinus (Gunther) and L. leptodon Regan are re-described and illustrated. An additional new species, L. longipinnis, sharing with the above the possession a steeply sloping, wedge-shaped snout, a slender lower pharyngeal bone and few (9—14) gillrakers is described. The status of L. lunaris Trewavas is discussed. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1978
- Authors: Eccles, David H , Lewis, Digby S C
- Date: 1978
- Subjects: Lethrinops -- Malawi, Lake -- Classification , Haplochromis -- Malawi, Lake -- Classification
- Language: English
- Type: Text
- Identifier: vital:14989 , http://hdl.handle.net/10962/d1018957 , ISBN 094998096x , Ichthyological Bulletin of the J.L.B. Smith Institute of Ichthyology; No. 37
- Description: Lethrinops argentea Ahl, L. lethrinus (Gunther) and L. leptodon Regan are re-described and illustrated. An additional new species, L. longipinnis, sharing with the above the possession a steeply sloping, wedge-shaped snout, a slender lower pharyngeal bone and few (9—14) gillrakers is described. The status of L. lunaris Trewavas is discussed. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1978
Abraham as a covenant mediator
- Authors: Mitchell, Gordon Barry
- Date: 1978
- Subjects: Abraham (Biblical patriarch) , Covenant theology -- Biblical teaching
- Language: English
- Type: Thesis , Bachelor , BDiv
- Identifier: vital:1238 , http://hdl.handle.net/10962/d1007657 , Abraham (Biblical patriarch) , Covenant theology -- Biblical teaching
- Description: Conclusion: The [Abrahamic] stories reveal a man caught up in the struggle of faith. But the God who took the initiative in establishing the Covenant shows that in spite of first appearances, He is faithful. The stories present various pictures of Abraham as a Covenant Mediator. Because he is in a sense Israel in microcosm it is not strange that he is described in the terms of Israel's most important institutions: prophet, priest, and king. Nevertheless the most significant Sitz im Leben is the family. While he is usually meant to be understood as an individual representing his immediate family, his descendants, and even all nations, at times, because he is the founding ancestor of Israel and therefore Israel in microcosm, he is best understood as a "Corporate Person". He and Israel are to be a source of blessing to the nations.
- Full Text:
- Date Issued: 1978
- Authors: Mitchell, Gordon Barry
- Date: 1978
- Subjects: Abraham (Biblical patriarch) , Covenant theology -- Biblical teaching
- Language: English
- Type: Thesis , Bachelor , BDiv
- Identifier: vital:1238 , http://hdl.handle.net/10962/d1007657 , Abraham (Biblical patriarch) , Covenant theology -- Biblical teaching
- Description: Conclusion: The [Abrahamic] stories reveal a man caught up in the struggle of faith. But the God who took the initiative in establishing the Covenant shows that in spite of first appearances, He is faithful. The stories present various pictures of Abraham as a Covenant Mediator. Because he is in a sense Israel in microcosm it is not strange that he is described in the terms of Israel's most important institutions: prophet, priest, and king. Nevertheless the most significant Sitz im Leben is the family. While he is usually meant to be understood as an individual representing his immediate family, his descendants, and even all nations, at times, because he is the founding ancestor of Israel and therefore Israel in microcosm, he is best understood as a "Corporate Person". He and Israel are to be a source of blessing to the nations.
- Full Text:
- Date Issued: 1978
Aloe ferox with striated leaves
- Authors: Skead, C J (Cuthbert John)
- Date: 1978
- Subjects: Aloe -- South Africa -- Eastern Cape -- Photographs
- Language: English
- Type: mixed material , photographs , landscape photographs
- Identifier: http://hdl.handle.net/10962/72798 , vital:30115
- Description: Caption: "Aloe ferox with striated leaves, probably diseased. Normal plants behind. On farm 'Clifton', 19 km NW Grahamstown, near Pigott Bridge, Fish River valley. Plant later removed to farm garden. 1978."
- Full Text: false
- Date Issued: 1978
- Authors: Skead, C J (Cuthbert John)
- Date: 1978
- Subjects: Aloe -- South Africa -- Eastern Cape -- Photographs
- Language: English
- Type: mixed material , photographs , landscape photographs
- Identifier: http://hdl.handle.net/10962/72798 , vital:30115
- Description: Caption: "Aloe ferox with striated leaves, probably diseased. Normal plants behind. On farm 'Clifton', 19 km NW Grahamstown, near Pigott Bridge, Fish River valley. Plant later removed to farm garden. 1978."
- Full Text: false
- Date Issued: 1978
An analysis of non-white transport requirements in an Eastern Cape urban area
- Authors: Viljoen, John
- Date: 1978
- Subjects: Buses -- South Africa -- Eastern Cape Black people -- Transportation -- South Africa -- Eastern Cape Transportation, Automotive -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:807 , http://hdl.handle.net/10962/d1007265
- Description: From Preface: The following research is centred around the Grahamstown non-white urban transportation problem. The bus service under consideration is owned and operated by the Grahamstown Municipality and is attached to the City Fire Department. It caters only for non-white commuters by operating fourteen buses, which carry approximately 1 200 000 people per year. As such, the difficulties encountered by this transport service should be generally, though not entirely, applicable only to relatively small non-white transport undertakings. The aims of this research are threefold: 1. to establish the environment within which transport undertakings operate, the structure of the undertaking in response to this environment and the problems which such undertakings encounter in their daily operations ; 2. by analysing in detail a specific transport service, an attempt has been made to delineate problem areas in both the cost and revenue structures, and to ascertain the degree of management awareness of the existence of these problems ; and 3. to determine the social impact of this transport operation and to evaluate all aspects of the service in relation to commuters, business and social needs and wants. Unfortunately, an attempt to extend this type of research to further Eastern Cape urban areas was unsuccessful due to the refusal by certain transport undertakings and government bodies to provide essential information.
- Full Text:
- Date Issued: 1978
- Authors: Viljoen, John
- Date: 1978
- Subjects: Buses -- South Africa -- Eastern Cape Black people -- Transportation -- South Africa -- Eastern Cape Transportation, Automotive -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:807 , http://hdl.handle.net/10962/d1007265
- Description: From Preface: The following research is centred around the Grahamstown non-white urban transportation problem. The bus service under consideration is owned and operated by the Grahamstown Municipality and is attached to the City Fire Department. It caters only for non-white commuters by operating fourteen buses, which carry approximately 1 200 000 people per year. As such, the difficulties encountered by this transport service should be generally, though not entirely, applicable only to relatively small non-white transport undertakings. The aims of this research are threefold: 1. to establish the environment within which transport undertakings operate, the structure of the undertaking in response to this environment and the problems which such undertakings encounter in their daily operations ; 2. by analysing in detail a specific transport service, an attempt has been made to delineate problem areas in both the cost and revenue structures, and to ascertain the degree of management awareness of the existence of these problems ; and 3. to determine the social impact of this transport operation and to evaluate all aspects of the service in relation to commuters, business and social needs and wants. Unfortunately, an attempt to extend this type of research to further Eastern Cape urban areas was unsuccessful due to the refusal by certain transport undertakings and government bodies to provide essential information.
- Full Text:
- Date Issued: 1978
An investigation into the effect of particulate solids on certain antimicrobial preservatives in pharmaceutical and cosmetic suspensions
- Authors: Horn, Norman Robert
- Date: 1978
- Subjects: Drugs -- Preservation , Drugs -- Microbiology , Cosmetics -- Preservation , Cosmetics -- Microbiology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3848 , http://hdl.handle.net/10962/d1012436 , Drugs -- Preservation , Drugs -- Microbiology , Cosmetics -- Preservation , Cosmetics -- Microbiology
- Description: Pharmaceutical and cosmetic preparations must be formulated so as to assure elegance of appearance, efficacy of ingredients and a satisfactory shelf life as the product. If the formulation is not self-preserving and if it contains material which could act as a substrate for growth of micro-organisms, the shelf life aspect involves, in addition to several other factors, the choice of a suitable antimicrobial preservative. Such preservatives, when present in the minimum effective concentration, are unfortunately prone to interact with many other materials. A number of papers on the inactivation of preservatives by containers, filters and formulation components have been published. The field has been adequately reviewed by de Navarre (1962), Wedderburn (1964) and, more recently, by Coates (1973). From these reviews and from a study of the literature it became apparent that relatively little work had been done on interactions between preservatives and solid particles in aqueous suspension. Consequently, a range of preservatives not previously investigated in this respect was tested for loss of activity in the presence of fifteen powders commonly used in aqueous suspension in pharmaceutical and cosmetic formulations. In view of the information obtained in this preliminary study and after the development of more satisfactory analytical techniques it was decided to study in greater depth the interaction between these powders and selected organomercurials and quaternary ammonium compounds.
- Full Text:
- Date Issued: 1978
- Authors: Horn, Norman Robert
- Date: 1978
- Subjects: Drugs -- Preservation , Drugs -- Microbiology , Cosmetics -- Preservation , Cosmetics -- Microbiology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3848 , http://hdl.handle.net/10962/d1012436 , Drugs -- Preservation , Drugs -- Microbiology , Cosmetics -- Preservation , Cosmetics -- Microbiology
- Description: Pharmaceutical and cosmetic preparations must be formulated so as to assure elegance of appearance, efficacy of ingredients and a satisfactory shelf life as the product. If the formulation is not self-preserving and if it contains material which could act as a substrate for growth of micro-organisms, the shelf life aspect involves, in addition to several other factors, the choice of a suitable antimicrobial preservative. Such preservatives, when present in the minimum effective concentration, are unfortunately prone to interact with many other materials. A number of papers on the inactivation of preservatives by containers, filters and formulation components have been published. The field has been adequately reviewed by de Navarre (1962), Wedderburn (1964) and, more recently, by Coates (1973). From these reviews and from a study of the literature it became apparent that relatively little work had been done on interactions between preservatives and solid particles in aqueous suspension. Consequently, a range of preservatives not previously investigated in this respect was tested for loss of activity in the presence of fifteen powders commonly used in aqueous suspension in pharmaceutical and cosmetic formulations. In view of the information obtained in this preliminary study and after the development of more satisfactory analytical techniques it was decided to study in greater depth the interaction between these powders and selected organomercurials and quaternary ammonium compounds.
- Full Text:
- Date Issued: 1978
Aphrodite
- Authors: Lautenbach, Janet
- Date: 1978
- Subjects: Aphrodite (Greek deity) , Idols and images -- Greece , Art, Greek , Aphrodite (Greek deity) in literature
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2448 , http://hdl.handle.net/10962/d1006914 , Aphrodite (Greek deity) , Idols and images -- Greece , Art, Greek , Aphrodite (Greek deity) in literature
- Full Text:
- Date Issued: 1978
- Authors: Lautenbach, Janet
- Date: 1978
- Subjects: Aphrodite (Greek deity) , Idols and images -- Greece , Art, Greek , Aphrodite (Greek deity) in literature
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2448 , http://hdl.handle.net/10962/d1006914 , Aphrodite (Greek deity) , Idols and images -- Greece , Art, Greek , Aphrodite (Greek deity) in literature
- Full Text:
- Date Issued: 1978
Bacterial degradation of ixodicide amitraz
- Authors: Allcock, Errol Ralph
- Date: 1978
- Subjects: Ticks -- Control , Pesticides -- Biodegradation , Acaricides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4081 , http://hdl.handle.net/10962/d1007473 , Ticks -- Control , Pesticides -- Biodegradation , Acaricides
- Description: The control of ticks on cattle has long been a matter of prime importance to stock owners over most of the intensive natural grazing areas in the Southern Hemisphere. The only practical method of dealing with the cattle tick problem in the short term is by treating the infected bovine host with ixodicides i. e. by chemical control. This can be achieved by either plunging the cattle into a dip tank containing aqueous suspensions or emulsions of the ixodicide or by spraying them with dip suspensions in a spray race.
- Full Text:
- Date Issued: 1978
- Authors: Allcock, Errol Ralph
- Date: 1978
- Subjects: Ticks -- Control , Pesticides -- Biodegradation , Acaricides
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4081 , http://hdl.handle.net/10962/d1007473 , Ticks -- Control , Pesticides -- Biodegradation , Acaricides
- Description: The control of ticks on cattle has long been a matter of prime importance to stock owners over most of the intensive natural grazing areas in the Southern Hemisphere. The only practical method of dealing with the cattle tick problem in the short term is by treating the infected bovine host with ixodicides i. e. by chemical control. This can be achieved by either plunging the cattle into a dip tank containing aqueous suspensions or emulsions of the ixodicide or by spraying them with dip suspensions in a spray race.
- Full Text:
- Date Issued: 1978
Community metabolism and phosphorus dynamics in a seasonally closed South African estuary
- Liptrot, Mark Robert Michael
- Authors: Liptrot, Mark Robert Michael
- Date: 1978
- Subjects: Estuarine ecology -- Research -- South Africa -- Swartvlei , Eelgrass -- Research -- South Africa , Enteromorpha -- Research -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5810 , http://hdl.handle.net/10962/d1006966 , Estuarine ecology -- Research -- South Africa -- Swartvlei , Eelgrass -- Research -- South Africa , Enteromorpha -- Research -- South Africa
- Description: The effects of seawater inflows and macrophyte beds on community metabolism and phosphorus dynamics in the seasonally-closed Swartvlei estuary were investigated. Metabolic rates were determined by diurnal oxygen curve analysis. Gross primary production ranged from 0,7 to 14,9 g 0₂ m⁻² day⁻¹, and respiration from 0,9 to 25,2 g 0₂ m⁻² day⁻¹. The highest production rates were recorded inside the dense beds of Zostera capens is Setchell (x- = 7,8 g 0₂ m⁻² day⁻¹ ). Metabolism was positively correlated to submersed macrophyte cover, and decreased upstream of the mouth region. No seasonal variation in gross production could be detected, and mouth closure had no detectable effect on metabolic rates. Growth of the green alga Enteromorpha sp. in winter, and the effect of decay of this alga on dissolved oxygen, total inorganic carbon and total dissolved phosphorus in the water column is discussed. High day-time respiration values, measured in a darkened polythene enclosure, indicate that photorespiration occurs in Zostera. Apparently the annual amount of oxygen respired throughout the estuary exceeded that produced by 2 7100 tonnes, i.e. the estuary was heterotrophic. This is discussed in relation to the effectiveness of the diurnal curve method as a way of measuring metabolic rates, and to the possibility of organic matter input via river inflows. There is a net gain of up to 17,4 kg of particulate phosphorus over mean tides. Diurnal phosphorus studies indicate that Zostera releases phosphate into the water column in the light. Enteromorpha takes up phosphate in the morning, which it appears to release over the rest of the day. The cycling of phosphorus between seawater, sediments, macrophytes and the water column is discussed.
- Full Text:
- Date Issued: 1978
- Authors: Liptrot, Mark Robert Michael
- Date: 1978
- Subjects: Estuarine ecology -- Research -- South Africa -- Swartvlei , Eelgrass -- Research -- South Africa , Enteromorpha -- Research -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5810 , http://hdl.handle.net/10962/d1006966 , Estuarine ecology -- Research -- South Africa -- Swartvlei , Eelgrass -- Research -- South Africa , Enteromorpha -- Research -- South Africa
- Description: The effects of seawater inflows and macrophyte beds on community metabolism and phosphorus dynamics in the seasonally-closed Swartvlei estuary were investigated. Metabolic rates were determined by diurnal oxygen curve analysis. Gross primary production ranged from 0,7 to 14,9 g 0₂ m⁻² day⁻¹, and respiration from 0,9 to 25,2 g 0₂ m⁻² day⁻¹. The highest production rates were recorded inside the dense beds of Zostera capens is Setchell (x- = 7,8 g 0₂ m⁻² day⁻¹ ). Metabolism was positively correlated to submersed macrophyte cover, and decreased upstream of the mouth region. No seasonal variation in gross production could be detected, and mouth closure had no detectable effect on metabolic rates. Growth of the green alga Enteromorpha sp. in winter, and the effect of decay of this alga on dissolved oxygen, total inorganic carbon and total dissolved phosphorus in the water column is discussed. High day-time respiration values, measured in a darkened polythene enclosure, indicate that photorespiration occurs in Zostera. Apparently the annual amount of oxygen respired throughout the estuary exceeded that produced by 2 7100 tonnes, i.e. the estuary was heterotrophic. This is discussed in relation to the effectiveness of the diurnal curve method as a way of measuring metabolic rates, and to the possibility of organic matter input via river inflows. There is a net gain of up to 17,4 kg of particulate phosphorus over mean tides. Diurnal phosphorus studies indicate that Zostera releases phosphate into the water column in the light. Enteromorpha takes up phosphate in the morning, which it appears to release over the rest of the day. The cycling of phosphorus between seawater, sediments, macrophytes and the water column is discussed.
- Full Text:
- Date Issued: 1978
Comparative blanching activities of proprietary diflucortolone valerate topical preparations
- Coleman, Gerald L, Kanfer, Isadore, Haigh, John M
- Authors: Coleman, Gerald L , Kanfer, Isadore , Haigh, John M
- Date: 1978
- Language: English
- Type: Article
- Identifier: vital:6350 , http://hdl.handle.net/10962/d1006032
- Description: The blanching activities and hence bioavailabilities of the cream, ointment and fatty ointment preparations of Nerisone and Temetex (diflucortolone valerate 0.1%) were evaluated using an occluded and unoccluded blanching assay. These products were compared to Synalar ointment and cream (fluocinolone acetonide 0.025%), established topical corticosteroid preparations. Statistical analysis showed no significant differences between similar formulations of diflucortolone valerate. Significant differences were noted between diflucortolone valerate and fluocinolone acetonide preparations.
- Full Text:
- Date Issued: 1978
- Authors: Coleman, Gerald L , Kanfer, Isadore , Haigh, John M
- Date: 1978
- Language: English
- Type: Article
- Identifier: vital:6350 , http://hdl.handle.net/10962/d1006032
- Description: The blanching activities and hence bioavailabilities of the cream, ointment and fatty ointment preparations of Nerisone and Temetex (diflucortolone valerate 0.1%) were evaluated using an occluded and unoccluded blanching assay. These products were compared to Synalar ointment and cream (fluocinolone acetonide 0.025%), established topical corticosteroid preparations. Statistical analysis showed no significant differences between similar formulations of diflucortolone valerate. Significant differences were noted between diflucortolone valerate and fluocinolone acetonide preparations.
- Full Text:
- Date Issued: 1978
Crocheted cardigan
- Date: 1978 , 2022-09-06
- Subjects: Bam, Brigalia , Crochet , Clothes
- Language: English
- Type: realia
- Identifier: http://hdl.handle.net/10948/56134 , vital:55940
- Description: A cardigan jersey made by Ms Bam Senior, which evoked feelings of joy and warmth. In 1978 Ms Bam Senior visited Dr Brigalia Bam in Switzerland and was surprised by the cold weather and told Dr Bam to buy wool in order for her to knit a jersey to keep her warm. Dr Bam never wore the jersey after her return as it made her miss her mom greatly. Mrs Bam Senior sewed Dr. Bam's first coat that she wore at school and she hated wearing it as other children did not have clothes but little blankets. Hence she hid it at home in the garden instead of wearing it. She wanted to be like other children. Ms Bam Senior sewed all Dr Bam's clothing and rarely bought anything from shops. , Photo taken of original garment as a JPEG image , Donated/gifted to Nelson Mandela University Archives by Dr Brigalia Bam , Forms part of: Brigalia Bam Collection
- Full Text: false
- Date Issued: 1978
- Date: 1978 , 2022-09-06
- Subjects: Bam, Brigalia , Crochet , Clothes
- Language: English
- Type: realia
- Identifier: http://hdl.handle.net/10948/56134 , vital:55940
- Description: A cardigan jersey made by Ms Bam Senior, which evoked feelings of joy and warmth. In 1978 Ms Bam Senior visited Dr Brigalia Bam in Switzerland and was surprised by the cold weather and told Dr Bam to buy wool in order for her to knit a jersey to keep her warm. Dr Bam never wore the jersey after her return as it made her miss her mom greatly. Mrs Bam Senior sewed Dr. Bam's first coat that she wore at school and she hated wearing it as other children did not have clothes but little blankets. Hence she hid it at home in the garden instead of wearing it. She wanted to be like other children. Ms Bam Senior sewed all Dr Bam's clothing and rarely bought anything from shops. , Photo taken of original garment as a JPEG image , Donated/gifted to Nelson Mandela University Archives by Dr Brigalia Bam , Forms part of: Brigalia Bam Collection
- Full Text: false
- Date Issued: 1978
Evidence for supposing that our Greek text of the gospel of St Mark is translated from Latin, that most of this Latin still survives, and that by following the Latin we can recover words and actions of Jesus which have been falsified in the Greek translation : inaugural lecture delivere at Rhodes University
- Authors: Gain, D B
- Date: 1978
- Subjects: Bible. Mark -- Translating , Bible. Mark -- Versions , Rhodes University -- History
- Language: English
- Type: text
- Identifier: vital:626 , http://hdl.handle.net/10962/d1020695
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1978
- Authors: Gain, D B
- Date: 1978
- Subjects: Bible. Mark -- Translating , Bible. Mark -- Versions , Rhodes University -- History
- Language: English
- Type: text
- Identifier: vital:626 , http://hdl.handle.net/10962/d1020695
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1978
From novice to master craftsman: a study of Athol Fugard's plays
- Authors: Hogge, David Somerville
- Date: 1978
- Subjects: Fugard, Athol -- Criticism and interpretation , Dramatists, South African -- 20th century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2302 , http://hdl.handle.net/10962/d1012328 , Fugard, Athol -- Criticism and interpretation , Dramatists, South African -- 20th century
- Description: Athol Fugard was born in Middelburg, Karroo, on the 11th June; 1932, his mother an Afrikaner, his father an English-speaking South African, possibly of Irish descent. When he was three years old, the family sold the small general dealer's store in the village and moved to Port Elizabeth, which has been his home ever since, though he has lived at various times in Europe, America, and other parts of Africa. After schooling at Port Elizabeth Technical College, he went to the University of Cape Town in 1950, where he read philosophy and social anthropology, supporting himself by working in the vacations as a waiter on the South African Railways. Chapter 1, p. 1.
- Full Text:
- Date Issued: 1978
- Authors: Hogge, David Somerville
- Date: 1978
- Subjects: Fugard, Athol -- Criticism and interpretation , Dramatists, South African -- 20th century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2302 , http://hdl.handle.net/10962/d1012328 , Fugard, Athol -- Criticism and interpretation , Dramatists, South African -- 20th century
- Description: Athol Fugard was born in Middelburg, Karroo, on the 11th June; 1932, his mother an Afrikaner, his father an English-speaking South African, possibly of Irish descent. When he was three years old, the family sold the small general dealer's store in the village and moved to Port Elizabeth, which has been his home ever since, though he has lived at various times in Europe, America, and other parts of Africa. After schooling at Port Elizabeth Technical College, he went to the University of Cape Town in 1950, where he read philosophy and social anthropology, supporting himself by working in the vacations as a waiter on the South African Railways. Chapter 1, p. 1.
- Full Text:
- Date Issued: 1978
Genetic and bacteriophage studies on Bacteroides thetaiotaomicron and related anaerobic strains
- Authors: Burt, Sharon Joy
- Date: 1978
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:20972 , http://hdl.handle.net/10962/5753
- Description: Gram-negative obligately anaerobic bacilli were isolated from faeces on selective media. R plasmid transfer was investigated in mating experiments between 30 anaerobes and between the anaerobes and known donor and recipient E. coli strains. The transfer of R plasmids from E.coli to B.fragilis, Bacteroides spp., Fusobacterium spp. and other faecal obligate anaerobic bacteria was possible after heat treatment of the recipients at 50°C. The anaerobic exconjugants were unstable and were not able to retransfer the ampr marker. A bacteriophage, B1 , specific for the anaerobe B.thetaiotaomicron, was isolated and characterised. The properties of the phage included a variable burst size and the production of many defective phage particles without tails which were not viable. The B.thetaiotaomicron host was able to establish a phage carrier state with B1 phage. Phenol-extracted phage DNA could transfect ca2+-treated B.thetaiotaomicron cells and transfection was not limited to a particular stage in the growth cycle. An obligatory step in the transfection procedure was a 33-fold dilution in broth, allowing replication of the infected cells. Prolonged incubation of treated cells with DNA prior to dilution in broth resulted in a large decrease in phage titre. The application of this transfection system to the development of a transformation system was not successful . Conventional transformation procedures did not yield transformants, and it was not possible to transduce B.thetaiotaomicron with B1 phage. The B.thetaiotaomicron strain used was distinguished by the formation of two distinct morphological variants. Each morphological type gave rise to the other at the same frequency. Environmental conditions other than elevated temperature, had no effect on the segregation frequency. The grey colony variant was not capsulated and was sensitive to B1 phage, whereas the white colony type was encapsulated and was phage-resistant. Another feature of the B.thetaiotaomicron strain was the low incidence of mutants. A second survey of the occurrence of R plasmids in aerobic coliforms from a remote area of the Transkei and from an urban area, was undertaken. An increase in transferable antibiotic resistance was found over the last three years. It can be concluded that this was a result of the use of antibiotics among the human population, since there are no veterinary services in the area and the addition of antibiotics to animal feeds is not practised.
- Full Text:
- Date Issued: 1978
- Authors: Burt, Sharon Joy
- Date: 1978
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:20972 , http://hdl.handle.net/10962/5753
- Description: Gram-negative obligately anaerobic bacilli were isolated from faeces on selective media. R plasmid transfer was investigated in mating experiments between 30 anaerobes and between the anaerobes and known donor and recipient E. coli strains. The transfer of R plasmids from E.coli to B.fragilis, Bacteroides spp., Fusobacterium spp. and other faecal obligate anaerobic bacteria was possible after heat treatment of the recipients at 50°C. The anaerobic exconjugants were unstable and were not able to retransfer the ampr marker. A bacteriophage, B1 , specific for the anaerobe B.thetaiotaomicron, was isolated and characterised. The properties of the phage included a variable burst size and the production of many defective phage particles without tails which were not viable. The B.thetaiotaomicron host was able to establish a phage carrier state with B1 phage. Phenol-extracted phage DNA could transfect ca2+-treated B.thetaiotaomicron cells and transfection was not limited to a particular stage in the growth cycle. An obligatory step in the transfection procedure was a 33-fold dilution in broth, allowing replication of the infected cells. Prolonged incubation of treated cells with DNA prior to dilution in broth resulted in a large decrease in phage titre. The application of this transfection system to the development of a transformation system was not successful . Conventional transformation procedures did not yield transformants, and it was not possible to transduce B.thetaiotaomicron with B1 phage. The B.thetaiotaomicron strain used was distinguished by the formation of two distinct morphological variants. Each morphological type gave rise to the other at the same frequency. Environmental conditions other than elevated temperature, had no effect on the segregation frequency. The grey colony variant was not capsulated and was sensitive to B1 phage, whereas the white colony type was encapsulated and was phage-resistant. Another feature of the B.thetaiotaomicron strain was the low incidence of mutants. A second survey of the occurrence of R plasmids in aerobic coliforms from a remote area of the Transkei and from an urban area, was undertaken. An increase in transferable antibiotic resistance was found over the last three years. It can be concluded that this was a result of the use of antibiotics among the human population, since there are no veterinary services in the area and the addition of antibiotics to animal feeds is not practised.
- Full Text:
- Date Issued: 1978
Geology of part of the central Damara belt around the Tumas River, South West Africa
- Authors: Bunting, F J L
- Date: 1978
- Subjects: Geology -- Namibia -- Damaraland , Geology, Stratigraphic -- Namibia , Geology -- Namibia -- Tumas River Watershed , Geology -- Namibia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5049 , http://hdl.handle.net/10962/d1009957 , Geology -- Namibia -- Damaraland , Geology, Stratigraphic -- Namibia , Geology -- Namibia -- Tumas River Watershed , Geology -- Namibia
- Description: The investigation covering 1500 square kilometres within the central granite zone of the Damara belt, South West Africa, revealed Pre - Damara (Abbabis) basement unconformably overlain by metasediments of the Damara Supergroup. The term Leeukop member is proposed for basal metaconglomerates of the Nosib Group that immediately overlie the basement augen-gneisses. Augen-gneiss clasts are present within the Leeukop metaconglomerates. The Damara orogeny has only partly affected the Abbabis rocks of the Tumas River Inlier but further to the west the Husab suite of red granites and granite-gneisses, as field and geochemical evidence suggest, were derived syntectonically during the Damara orogeny by reactivation of the pre- Damara basement. Rõssing alaskitic granites represent late stage melts, that were also derived from Pre- Damara basement rocks during orogenesis, which accumulated post-tectonically in structural traps at the base of the Khomas Subgroup. Salem granitoids are present in synclinal structures associated with metasediments of the Khomas Subgroup and syntectonic derivation by anatexis during the Damara orogeny is suggested. In the east the differentiated Gawib granitoid stock was emplaced post- tectonically through basement rocks into the Damara metasediments. A deep seated origin is indicated by high crystallisation temperatures (>8500°) obtained from quarternary Qz-An-Ab-Or- H₂0 plots. The metamorphic grade increases westwards from medium grade to high grade. In the east, the metapelites contain andalusite, and coexisting muscovite and quartz. This indicates that temperatures of 6000° at 3,5- 4 kb pressure were attained. In the west, coexisting wollastonite and anorthite in the Khan gneisses indicate pressure- temperature conditions of 720° at 4,5-5 kb. Two tectonic events were responsible for the regional structure. An early F₁ episode produced east- west oriented overturned folds and was followed by an intense F₂ episode of isoclinal folding which is responsible for the dominant northeast - southwest regional fabric. The interference of these folds in the proximity of the underlying basement produced the complex dome and basin structures seen in the central and western parts of the area. An F₃ episode of minor importance was also recognized. The presence of continental basement rocks in this central part of the Damara belt is evidence for formation of the orogen by in-situ deformation rather than continental collision.
- Full Text:
- Date Issued: 1978
- Authors: Bunting, F J L
- Date: 1978
- Subjects: Geology -- Namibia -- Damaraland , Geology, Stratigraphic -- Namibia , Geology -- Namibia -- Tumas River Watershed , Geology -- Namibia
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5049 , http://hdl.handle.net/10962/d1009957 , Geology -- Namibia -- Damaraland , Geology, Stratigraphic -- Namibia , Geology -- Namibia -- Tumas River Watershed , Geology -- Namibia
- Description: The investigation covering 1500 square kilometres within the central granite zone of the Damara belt, South West Africa, revealed Pre - Damara (Abbabis) basement unconformably overlain by metasediments of the Damara Supergroup. The term Leeukop member is proposed for basal metaconglomerates of the Nosib Group that immediately overlie the basement augen-gneisses. Augen-gneiss clasts are present within the Leeukop metaconglomerates. The Damara orogeny has only partly affected the Abbabis rocks of the Tumas River Inlier but further to the west the Husab suite of red granites and granite-gneisses, as field and geochemical evidence suggest, were derived syntectonically during the Damara orogeny by reactivation of the pre- Damara basement. Rõssing alaskitic granites represent late stage melts, that were also derived from Pre- Damara basement rocks during orogenesis, which accumulated post-tectonically in structural traps at the base of the Khomas Subgroup. Salem granitoids are present in synclinal structures associated with metasediments of the Khomas Subgroup and syntectonic derivation by anatexis during the Damara orogeny is suggested. In the east the differentiated Gawib granitoid stock was emplaced post- tectonically through basement rocks into the Damara metasediments. A deep seated origin is indicated by high crystallisation temperatures (>8500°) obtained from quarternary Qz-An-Ab-Or- H₂0 plots. The metamorphic grade increases westwards from medium grade to high grade. In the east, the metapelites contain andalusite, and coexisting muscovite and quartz. This indicates that temperatures of 6000° at 3,5- 4 kb pressure were attained. In the west, coexisting wollastonite and anorthite in the Khan gneisses indicate pressure- temperature conditions of 720° at 4,5-5 kb. Two tectonic events were responsible for the regional structure. An early F₁ episode produced east- west oriented overturned folds and was followed by an intense F₂ episode of isoclinal folding which is responsible for the dominant northeast - southwest regional fabric. The interference of these folds in the proximity of the underlying basement produced the complex dome and basin structures seen in the central and western parts of the area. An F₃ episode of minor importance was also recognized. The presence of continental basement rocks in this central part of the Damara belt is evidence for formation of the orogen by in-situ deformation rather than continental collision.
- Full Text:
- Date Issued: 1978
Heterotrophic carbon dioxide fixation by Euglena
- Authors: Peak, Jennifer Grace
- Date: 1978
- Subjects: Euglena
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5824 , http://hdl.handle.net/10962/d1007650
- Description: Heterotrophic (dark, non-photosynthetic) carbon dioxide fixation was measured in the phytoflagellate Euglena gracilis. Variation in heterotrophic carbon dioxide fixation depends on the phase of batch growth and the mode of nutrition. A sharp increase in heterotrophic carbon dioxide fixation occurs during the mid- to late-logarithmic growth periods in Euglena growing photoautotrophically (with carbon dioxide as carbon source, light as energy source) and heterotrophically (in the dark with glucose as sole carbon and energy source). Cells growing heterotrophically with acetate or ethanol as sole carbon source do not increase their heterotrophic carbon dioxide fixation during the growth cycle. Addition of acetate to cultures of Euglena causes a reduction in dark carbon dioxide fixation. The results are consistent with the hypothesis that heterotrophic carbon dioxide fixation in Euglena functions in anaplerotic replenishment of the tricarboxylic acid cycle. The regulation of these changes in heterotrophic carbon dioxide fixation was shown to be controlled by exogenous ammonium in a complex fashion. Ammonium stimulates heterotrophic carbon dioxide fixation after a period of ammonium deprivation. The kinetics of the regulatory effects of the ammonium ion on dark carbon dioxide fixation are presented. A survey into the activities of carboxylating enzymes from both autotrophically and heterotrophically grown Euglena was conducted. The heterotrophic cultures were supplied with either glucose or acetate as substrate. PEP carboxykinase (E.C.4.1.1.38) and (E.C.4.1.1.49) could not be detected in any of the cultures tested. A trace amount of PEP carboxykinase (E.C.4.1.1.32) is present in the acetate grown cells only and a trace amount of pyruvate carboxylase (E.C.6.4.1.1.) is present in the glucose grown cells only. Malate enzyme (E.C.1.1.1.40), PEP carboxylase (E.C.4.1.1.31) and acetylcoenzyme A carboxylase (E.C.6.4.1.2) are present in all cells tested. Ammonium stimulation causes a small increase in specific activity of all the enzymes except acetyl-CoA carboxylase. The largest increase occurs in PEP carboxylase, but the increase is not sufficient to account for observed increases in whole cell dark carbon dioxide fixation after ammonium stimulation. Two isoenzymes of PEP carboxylase were purified from each other from both ammonium stimulated and non-stimulated cells. There are no significant differences between elution profiles of isoenzymes from ammonium stimulated and control cells. There are no significant differences between elution profiles of isoenzymes from autotrophic and heterotrophic cells. The kinetics of the regulation of the two isoenzymes by malate, citrate, succinate and 3-phosphoglycerate are presented. The products of heterotrophic carbon dioxide fixation by ammonium stimulated and control cells were identified and measured by chromatography. Ammonium stimulates the biosynthesis of glutamine, glycine, serine and alanine.
- Full Text:
- Date Issued: 1978
- Authors: Peak, Jennifer Grace
- Date: 1978
- Subjects: Euglena
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5824 , http://hdl.handle.net/10962/d1007650
- Description: Heterotrophic (dark, non-photosynthetic) carbon dioxide fixation was measured in the phytoflagellate Euglena gracilis. Variation in heterotrophic carbon dioxide fixation depends on the phase of batch growth and the mode of nutrition. A sharp increase in heterotrophic carbon dioxide fixation occurs during the mid- to late-logarithmic growth periods in Euglena growing photoautotrophically (with carbon dioxide as carbon source, light as energy source) and heterotrophically (in the dark with glucose as sole carbon and energy source). Cells growing heterotrophically with acetate or ethanol as sole carbon source do not increase their heterotrophic carbon dioxide fixation during the growth cycle. Addition of acetate to cultures of Euglena causes a reduction in dark carbon dioxide fixation. The results are consistent with the hypothesis that heterotrophic carbon dioxide fixation in Euglena functions in anaplerotic replenishment of the tricarboxylic acid cycle. The regulation of these changes in heterotrophic carbon dioxide fixation was shown to be controlled by exogenous ammonium in a complex fashion. Ammonium stimulates heterotrophic carbon dioxide fixation after a period of ammonium deprivation. The kinetics of the regulatory effects of the ammonium ion on dark carbon dioxide fixation are presented. A survey into the activities of carboxylating enzymes from both autotrophically and heterotrophically grown Euglena was conducted. The heterotrophic cultures were supplied with either glucose or acetate as substrate. PEP carboxykinase (E.C.4.1.1.38) and (E.C.4.1.1.49) could not be detected in any of the cultures tested. A trace amount of PEP carboxykinase (E.C.4.1.1.32) is present in the acetate grown cells only and a trace amount of pyruvate carboxylase (E.C.6.4.1.1.) is present in the glucose grown cells only. Malate enzyme (E.C.1.1.1.40), PEP carboxylase (E.C.4.1.1.31) and acetylcoenzyme A carboxylase (E.C.6.4.1.2) are present in all cells tested. Ammonium stimulation causes a small increase in specific activity of all the enzymes except acetyl-CoA carboxylase. The largest increase occurs in PEP carboxylase, but the increase is not sufficient to account for observed increases in whole cell dark carbon dioxide fixation after ammonium stimulation. Two isoenzymes of PEP carboxylase were purified from each other from both ammonium stimulated and non-stimulated cells. There are no significant differences between elution profiles of isoenzymes from ammonium stimulated and control cells. There are no significant differences between elution profiles of isoenzymes from autotrophic and heterotrophic cells. The kinetics of the regulation of the two isoenzymes by malate, citrate, succinate and 3-phosphoglycerate are presented. The products of heterotrophic carbon dioxide fixation by ammonium stimulated and control cells were identified and measured by chromatography. Ammonium stimulates the biosynthesis of glutamine, glycine, serine and alanine.
- Full Text:
- Date Issued: 1978