The biology and management considerations of abundant large cyprinids in Lake le Roux, Orange River, South Africa
- Authors: Tómasson, Tumi
- Date: 1983
- Subjects: Barbus Labeo Cyprinidae Freshwater fishes -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5206 , http://hdl.handle.net/10962/d1004518
- Description: The biology of three large cyprinid fishes, Barbus holubi, B. kimberleyensis and Labeo capensis, was studied in a large turbid man-made lake on the Orange River, South Africa. The influence of environmental fluctuations on population dynamics was examined in relation to biological adaptations. On this basis inferences were made about the effect exploitation would have on the populations, and management alternatives were considered. Lake Ie Roux is situated in a semi- arid area, downstream from another large reservoir, Lake Verwoerd. In the pristine river, flooding is seasonal, and floodwaters carry a heavy silt load. Lake Verwoerd acts as a silt-trap and changes in turbidity in Lake Ie Roux (Secchi disc readings range from 15 to 160 cm) are influenced by hydrological management and are not necessarily seasonal. Water temperatures in the regulated river connecting the two lakes depend on the pattern of water release, and fluctuations in Iake levels depend on management practices. Reproduction was studied by examination of gonads and from the distribution of newly hatched juveniles. Age and growth was interpreted from the reading of scales and otoliths. Relative year class strength, dispersal and mortality were monitored using catch data from a regular, standardized gillnetting survey. The Barbus species spawn in the regulated river in spring or summer. Spawning is coordinated for a large part of the population and B. holubi spawn four to six weeks earlier than B. kimberleyensis. The juveniles are 'initially found along the shoreline, but later move into the pelagic zone and disperse throughout the lake. Year class strength is dependent on time of spawning and a late spawning results in a poor year class. For this reason, year class strength of B. kimberleyensis is generally poor, but there is a greater variation in year class strength of B. holubi, which is the dominant large Barbus. The two Barbus species exploit the pelagic zone, visually predating on zooplankton. When turbidity increases large scale mortalities occur, especially in B. holubi. Mortalities more than compensate for the reduction in carrying capacity, and the size of the reduced population may be inversely related to initial abundance. Growth rate is similarly affected by turbidity and density, and size at sexual maturity in B. holubi is reduced when growing conditions deteriorate. Labeo capensis do not form a homogenous population in Lake le Roux. Spawning occurs throughout the lake, but is erratic, probably depending on local rainfall. At each locality, more than one spawning may occur during spring and summer because of temporal variation in gonadal development. Juvenile survival appears to be mainly dependent on water level fluctuations, and strong year classes were formed when the lake was filling during the first two years. Subsequent year classes were weak. Subadult and adult B. capensis are herbivorous and depend on autochthonous production for food. They are relatively sedentary, but when turbidity increases fish smaller than 200 mm disperse, probably in response to food shortages. Mortality rates may be accelerated but mortalities are not as high as in B. holubi. The growth rate of B. capensis is variable and depends on turbidity and population density. Size at sexual maturity remained relatively constant during the study period. B. holubi has a relatively fixed reproduction cycle in Lake le Roux and exploitation is likely to dampen fluctuations in population density. Population growth and stability could be further promoted through hydrological management. B. kimberleyensis does not represent an exploitable population in Lake le Roux, although the large size obtained by this species (>3 kg) may be an attraction to anglers. B. capensis does not appear to have the potential to withstand sustained exploitation because of its erratic and generally poor reproductive success. However, the species is long-lived and can sustain relatively high densities under harsh conditions because of its relatively low mortality rates. It was concluded that harvesting of B. holubi must be flexible to promote maximum benefits to commercial and recreational fisheries, but B. capensis which is not an angling species, should chiefly be exploited when catches of B. holubi are poor, but left to recover in between. An alternative management strategy would be to commercially exploit the fish populations of several reservoirs. A monitoring programme could be established to decide when each reservoir is to be exploited to see to the interests of commercial and recreational fishing alike.
- Full Text:
- Date Issued: 1983
- Authors: Tómasson, Tumi
- Date: 1983
- Subjects: Barbus Labeo Cyprinidae Freshwater fishes -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5206 , http://hdl.handle.net/10962/d1004518
- Description: The biology of three large cyprinid fishes, Barbus holubi, B. kimberleyensis and Labeo capensis, was studied in a large turbid man-made lake on the Orange River, South Africa. The influence of environmental fluctuations on population dynamics was examined in relation to biological adaptations. On this basis inferences were made about the effect exploitation would have on the populations, and management alternatives were considered. Lake Ie Roux is situated in a semi- arid area, downstream from another large reservoir, Lake Verwoerd. In the pristine river, flooding is seasonal, and floodwaters carry a heavy silt load. Lake Verwoerd acts as a silt-trap and changes in turbidity in Lake Ie Roux (Secchi disc readings range from 15 to 160 cm) are influenced by hydrological management and are not necessarily seasonal. Water temperatures in the regulated river connecting the two lakes depend on the pattern of water release, and fluctuations in Iake levels depend on management practices. Reproduction was studied by examination of gonads and from the distribution of newly hatched juveniles. Age and growth was interpreted from the reading of scales and otoliths. Relative year class strength, dispersal and mortality were monitored using catch data from a regular, standardized gillnetting survey. The Barbus species spawn in the regulated river in spring or summer. Spawning is coordinated for a large part of the population and B. holubi spawn four to six weeks earlier than B. kimberleyensis. The juveniles are 'initially found along the shoreline, but later move into the pelagic zone and disperse throughout the lake. Year class strength is dependent on time of spawning and a late spawning results in a poor year class. For this reason, year class strength of B. kimberleyensis is generally poor, but there is a greater variation in year class strength of B. holubi, which is the dominant large Barbus. The two Barbus species exploit the pelagic zone, visually predating on zooplankton. When turbidity increases large scale mortalities occur, especially in B. holubi. Mortalities more than compensate for the reduction in carrying capacity, and the size of the reduced population may be inversely related to initial abundance. Growth rate is similarly affected by turbidity and density, and size at sexual maturity in B. holubi is reduced when growing conditions deteriorate. Labeo capensis do not form a homogenous population in Lake le Roux. Spawning occurs throughout the lake, but is erratic, probably depending on local rainfall. At each locality, more than one spawning may occur during spring and summer because of temporal variation in gonadal development. Juvenile survival appears to be mainly dependent on water level fluctuations, and strong year classes were formed when the lake was filling during the first two years. Subsequent year classes were weak. Subadult and adult B. capensis are herbivorous and depend on autochthonous production for food. They are relatively sedentary, but when turbidity increases fish smaller than 200 mm disperse, probably in response to food shortages. Mortality rates may be accelerated but mortalities are not as high as in B. holubi. The growth rate of B. capensis is variable and depends on turbidity and population density. Size at sexual maturity remained relatively constant during the study period. B. holubi has a relatively fixed reproduction cycle in Lake le Roux and exploitation is likely to dampen fluctuations in population density. Population growth and stability could be further promoted through hydrological management. B. kimberleyensis does not represent an exploitable population in Lake le Roux, although the large size obtained by this species (>3 kg) may be an attraction to anglers. B. capensis does not appear to have the potential to withstand sustained exploitation because of its erratic and generally poor reproductive success. However, the species is long-lived and can sustain relatively high densities under harsh conditions because of its relatively low mortality rates. It was concluded that harvesting of B. holubi must be flexible to promote maximum benefits to commercial and recreational fisheries, but B. capensis which is not an angling species, should chiefly be exploited when catches of B. holubi are poor, but left to recover in between. An alternative management strategy would be to commercially exploit the fish populations of several reservoirs. A monitoring programme could be established to decide when each reservoir is to be exploited to see to the interests of commercial and recreational fishing alike.
- Full Text:
- Date Issued: 1983
The biology of the sand shark Rhinobatos Annulatus, in Algoa Bay with notes on other elasmobranchs
- Authors: Rossouw, Gideon Johannes
- Date: 1983
- Subjects: Sand sharks , Guitarfishes
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/52802 , vital:44061
- Description: The biology of the lesser sand shark, Rhinobatos annulatus, was studied off sandy beaches in Algoa Bay over a period of two years. Tagging studies, due to low numbers tagged, did not reveal major movements. However, comparison of numbers of sand sharks caught off the beach and deep water during summer and winter months suggested that migration occurred during these seasons with the animals being inshore in summer. Annual rings on the vertebral centra were used to determine age. Both sexes can reach a maximum age of seven years. Conventional growth curves could not be fitted and empirical curves were used to illustrate growth. The reproductive cycle was investigated and indicated that both sexes matured after three years of age. The breeding season was during late summer when the shallow water was utilized as a nursery area. The sand shark is an aplacental viviparous species with a gestation period of 10 months. Breeding occurred every year and fecundity increased with total body length to a maximum litter size of 10 young. The most important prey items taken inshore were the mysid Gastrosaccus psammodytes, the prawn Macropetasma africanum, the crab Ovalipes punctatus and the sand mussels Donax spp. Differential predation by different length classes of sand shark resulted from a dynamic zonation of these different size classes in the surf zone. Smallest individuals fed closest inshore. Seasonal variation recorded in the hepatosomatic index was primarily due to the accumulation of hepatic lipids. This variation showed significant correlations with the breeding cycle in adult sand sharks. The contribution of liver lipids to the formation of egg yolk was estimated and found to be secondary to lipid reserves for maintenance. Liver colour varied depended on the amount of liver lipids. Ancillary observations were made of other elasmobranchs in the surf zone. , Thesis (DPhil) -- Faculty of Science, 1983
- Full Text:
- Date Issued: 1983
- Authors: Rossouw, Gideon Johannes
- Date: 1983
- Subjects: Sand sharks , Guitarfishes
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/52802 , vital:44061
- Description: The biology of the lesser sand shark, Rhinobatos annulatus, was studied off sandy beaches in Algoa Bay over a period of two years. Tagging studies, due to low numbers tagged, did not reveal major movements. However, comparison of numbers of sand sharks caught off the beach and deep water during summer and winter months suggested that migration occurred during these seasons with the animals being inshore in summer. Annual rings on the vertebral centra were used to determine age. Both sexes can reach a maximum age of seven years. Conventional growth curves could not be fitted and empirical curves were used to illustrate growth. The reproductive cycle was investigated and indicated that both sexes matured after three years of age. The breeding season was during late summer when the shallow water was utilized as a nursery area. The sand shark is an aplacental viviparous species with a gestation period of 10 months. Breeding occurred every year and fecundity increased with total body length to a maximum litter size of 10 young. The most important prey items taken inshore were the mysid Gastrosaccus psammodytes, the prawn Macropetasma africanum, the crab Ovalipes punctatus and the sand mussels Donax spp. Differential predation by different length classes of sand shark resulted from a dynamic zonation of these different size classes in the surf zone. Smallest individuals fed closest inshore. Seasonal variation recorded in the hepatosomatic index was primarily due to the accumulation of hepatic lipids. This variation showed significant correlations with the breeding cycle in adult sand sharks. The contribution of liver lipids to the formation of egg yolk was estimated and found to be secondary to lipid reserves for maintenance. Liver colour varied depended on the amount of liver lipids. Ancillary observations were made of other elasmobranchs in the surf zone. , Thesis (DPhil) -- Faculty of Science, 1983
- Full Text:
- Date Issued: 1983
The concept of grade in mineral deposits
- Authors: Esterhuizen, Anton G
- Date: 1983 , 2013-04-04
- Subjects: Mines and mineral resources , Ore deposits , Mineralogy , Geology, Economic
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5020 , http://hdl.handle.net/10962/d1006331 , Mines and mineral resources , Ore deposits , Mineralogy , Geology, Economic
- Description: The grade of a mineral deposit is determined by the effectiveness of a geological ore forming process, which is the result of the interaction between an ore forming mechanism and the environment in which it operates. Properties of a mineral deposit controlled by ore forming processes include the distribution, density and nature of ore minerals and gangue, and the metal content and impurities of the ore minerals. More efficient ore forming processes tend to develop in the larger mineralizing systems giving rise to richer deposits. As the geological environment within which a mineral deposit evolves becomes more complex a greater number of variables interact to determine the grade of the deposit. This is reflected in the greater variability of the grade distribution, resulting in greater difficulties in obtaining reliable estimates of the recoverable grade, and increased difficulties in the processing of ores. In response to economic fluctuations the working grade of heterogeneous orebodies, that form in geologically complex environments, can often be altered to ensure the continued viability of a mining venture. In contrast the evenly mineralized orebodies that tend to develop in geologically simple environments do not have this flexibility. All the important decisions in the mining industry, such as feasibility studies, choice of ~ining and processing methods, selection and planning, are made on the basis of, or are related to, grade estimates. If the geological controls of grade are fully understood, then it is possible to optimize the selection of the various mining alternatives, leading to the efficient exploitation of ore deposits.
- Full Text:
- Date Issued: 1983
- Authors: Esterhuizen, Anton G
- Date: 1983 , 2013-04-04
- Subjects: Mines and mineral resources , Ore deposits , Mineralogy , Geology, Economic
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5020 , http://hdl.handle.net/10962/d1006331 , Mines and mineral resources , Ore deposits , Mineralogy , Geology, Economic
- Description: The grade of a mineral deposit is determined by the effectiveness of a geological ore forming process, which is the result of the interaction between an ore forming mechanism and the environment in which it operates. Properties of a mineral deposit controlled by ore forming processes include the distribution, density and nature of ore minerals and gangue, and the metal content and impurities of the ore minerals. More efficient ore forming processes tend to develop in the larger mineralizing systems giving rise to richer deposits. As the geological environment within which a mineral deposit evolves becomes more complex a greater number of variables interact to determine the grade of the deposit. This is reflected in the greater variability of the grade distribution, resulting in greater difficulties in obtaining reliable estimates of the recoverable grade, and increased difficulties in the processing of ores. In response to economic fluctuations the working grade of heterogeneous orebodies, that form in geologically complex environments, can often be altered to ensure the continued viability of a mining venture. In contrast the evenly mineralized orebodies that tend to develop in geologically simple environments do not have this flexibility. All the important decisions in the mining industry, such as feasibility studies, choice of ~ining and processing methods, selection and planning, are made on the basis of, or are related to, grade estimates. If the geological controls of grade are fully understood, then it is possible to optimize the selection of the various mining alternatives, leading to the efficient exploitation of ore deposits.
- Full Text:
- Date Issued: 1983
The demand for skilled labour in the Border, Ciskei, Southern Transkei regional economy
- Authors: McCartan, P J
- Date: 1983
- Subjects: Working class -- South Africa Cape of Good Hope (South Africa) -- Economic conditions Good hope plan Border (Eastern Cape, South Africa) Ciskei (South Africa) -- Economic conditions Transkei (South Africa) -- Economic conditions
- Language: English
- Type: Book , Text
- Identifier: http://hdl.handle.net/10962/2112 , vital:20256 , ISBN 0868100587
- Description: The aim of the study is to broadly assess the demand for skilled and semi-skilled labour in the existing industries in that part of Region D of the Good Hope Plan comprising the Border corridor, the Ciskei and southern Transkei (hereafter referred to as the survey region). This survey region was chosen as the target area, since firstly, all of Region D's growth points are located within it and, secondly, technical training facilities in the survey region are recognised as being inadequate. This study does not aim to specify the type of technical training institution that should be established in the survey region; rather it analyses the demand-side of the regional labour market in order to identify the nature and extent of the perceived need for skilled labour. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
- Full Text:
- Date Issued: 1983
- Authors: McCartan, P J
- Date: 1983
- Subjects: Working class -- South Africa Cape of Good Hope (South Africa) -- Economic conditions Good hope plan Border (Eastern Cape, South Africa) Ciskei (South Africa) -- Economic conditions Transkei (South Africa) -- Economic conditions
- Language: English
- Type: Book , Text
- Identifier: http://hdl.handle.net/10962/2112 , vital:20256 , ISBN 0868100587
- Description: The aim of the study is to broadly assess the demand for skilled and semi-skilled labour in the existing industries in that part of Region D of the Good Hope Plan comprising the Border corridor, the Ciskei and southern Transkei (hereafter referred to as the survey region). This survey region was chosen as the target area, since firstly, all of Region D's growth points are located within it and, secondly, technical training facilities in the survey region are recognised as being inadequate. This study does not aim to specify the type of technical training institution that should be established in the survey region; rather it analyses the demand-side of the regional labour market in order to identify the nature and extent of the perceived need for skilled labour. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
- Full Text:
- Date Issued: 1983
The effect of the feminist movement on painting and sculpture in Europe and America after 1945
- Authors: Brooks, Jennifer
- Date: 1983
- Subjects: Painting, American -- 20th century Painting, European -- 20th century Sculpture, European -- 20th century Sculpture, American -- 20th century Feminism and art -- United States Feminism and art -- Europe
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2459 , http://hdl.handle.net/10962/d1007675
- Description: My investigation of women artists and their status in society today as a result of the feminist movement, revealed issues which, I felt, were multifaceted. This necessitated an exploration of many aspects in order to arrive at a fairly satisfactory conclusion as to whether the revolt and the aggression on the part of the feminists had borne any fruit, either generally in everyday life, or artistically. It has proved most stimulating and informative. I think that the need to assess oneself as a woman, working within a male-dominated creative environment is a very necessary process and one which has been most beneficial to me. The subsequent research revealed that a radical, thematic change had occured within the feminist movement at the start of the Eighties; a fact of which, till recently, I was largely unaware. What I discovered was that the militant, feminist approach of the Sixties and Seventies had given way to a more realistic involvement brought on partly by the economic recession and the effects as well of earlier feminist movements, leading to a relaxation on the part of the younger generation. The Violence had faded. Hard times curbed the excesses of the movement and took it along the road to practicality. Dovetailed to this and seeming to run concurrently was the phenomenon of the demise of the Modern Art Movement. These changes described were not only artistic and feminist, but cut right across the board. involving all facets of life. To take one as an example. the political with conservatism reinstating itself in America not merely as an alternative but as a worthwhile direction in itself. Other issues included the sociological, historical, biological, and cultural; all closely interwoven and therefore requiring some generalisations at times. Previous to becoming involved with my topic, I had been reacting to pre-conceived ideas laid on me as a student in the Sixties and Seventies - a militant, aggressive approach acquired as a protective shield, to deal with the masculine environment which denigrated in varying degrees mine and fellow female artists work, sometimes overtly, sometimes subconsciously. This discrimination, is usually denied as ever having existed by the men involved. It shows a lack of awareness of what, we, as female art students, were subjected to. This is one of the main reasons why I undertook this subject; partly out of interest and perhaps partly as some sort of catharsis.
- Full Text:
- Date Issued: 1983
- Authors: Brooks, Jennifer
- Date: 1983
- Subjects: Painting, American -- 20th century Painting, European -- 20th century Sculpture, European -- 20th century Sculpture, American -- 20th century Feminism and art -- United States Feminism and art -- Europe
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2459 , http://hdl.handle.net/10962/d1007675
- Description: My investigation of women artists and their status in society today as a result of the feminist movement, revealed issues which, I felt, were multifaceted. This necessitated an exploration of many aspects in order to arrive at a fairly satisfactory conclusion as to whether the revolt and the aggression on the part of the feminists had borne any fruit, either generally in everyday life, or artistically. It has proved most stimulating and informative. I think that the need to assess oneself as a woman, working within a male-dominated creative environment is a very necessary process and one which has been most beneficial to me. The subsequent research revealed that a radical, thematic change had occured within the feminist movement at the start of the Eighties; a fact of which, till recently, I was largely unaware. What I discovered was that the militant, feminist approach of the Sixties and Seventies had given way to a more realistic involvement brought on partly by the economic recession and the effects as well of earlier feminist movements, leading to a relaxation on the part of the younger generation. The Violence had faded. Hard times curbed the excesses of the movement and took it along the road to practicality. Dovetailed to this and seeming to run concurrently was the phenomenon of the demise of the Modern Art Movement. These changes described were not only artistic and feminist, but cut right across the board. involving all facets of life. To take one as an example. the political with conservatism reinstating itself in America not merely as an alternative but as a worthwhile direction in itself. Other issues included the sociological, historical, biological, and cultural; all closely interwoven and therefore requiring some generalisations at times. Previous to becoming involved with my topic, I had been reacting to pre-conceived ideas laid on me as a student in the Sixties and Seventies - a militant, aggressive approach acquired as a protective shield, to deal with the masculine environment which denigrated in varying degrees mine and fellow female artists work, sometimes overtly, sometimes subconsciously. This discrimination, is usually denied as ever having existed by the men involved. It shows a lack of awareness of what, we, as female art students, were subjected to. This is one of the main reasons why I undertook this subject; partly out of interest and perhaps partly as some sort of catharsis.
- Full Text:
- Date Issued: 1983
The effect of tricyclic antidepressant drugs on the uptake and metabolism of serotonin by the pineal gland in organ culture
- Authors: Pillay, Manoranjenni
- Date: 1983 , 2013-04-05
- Subjects: Antidepressants , Pineal gland -- Metabolsim , Serotonin
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3828 , http://hdl.handle.net/10962/d1007053 , Antidepressants , Pineal gland -- Metabolsim , Serotonin
- Description: The effect of tricyclic antidepressants (TADs) on a variety of pineal functions was assessed. TADs affected the uptake of ³H-5HT into bovine pineal slices within a particular concentration range of these drugs, DESI, CLOMI and IMI appeared to inhibit uptake slightly, within a limited concentration range. Surprisingly, DESI appeared to be a relatively potent 5HT uptake inhibitor. The 5-HT re-uptake system in the pineal probably differes from that in brain tissue. TADs had a marked effect on the metabolism of ³H-5HT in the rat pineal, in an organ culture system, MEL and N-acetylserotonin synthesis increased for the first 11 days and thereafter a slight decrease was observed. HTOH and HIAA also showed an initial increase followed by a slight decrease in synthesis. The synthesis of MTOH and MIAA was decreased. The possibility that TADs could affect HIOMT and SNAT synthesis and thereby change the metabolic pattern of 5-HT was investigated. TADs appeared to stimulate SNAT initially and thereafter a slight decrease from peak activity was observed. This is probably due to stimulation followed by development of subsensitivity of β-receptors, HIOMT activity also appeared to be affected by TADs. The existence of two types of HIOMT is suggested. There is a possibility that these changes in the metabolism of 5-HT could be implicated in the mechanism of action of TADs. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1983
- Authors: Pillay, Manoranjenni
- Date: 1983 , 2013-04-05
- Subjects: Antidepressants , Pineal gland -- Metabolsim , Serotonin
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3828 , http://hdl.handle.net/10962/d1007053 , Antidepressants , Pineal gland -- Metabolsim , Serotonin
- Description: The effect of tricyclic antidepressants (TADs) on a variety of pineal functions was assessed. TADs affected the uptake of ³H-5HT into bovine pineal slices within a particular concentration range of these drugs, DESI, CLOMI and IMI appeared to inhibit uptake slightly, within a limited concentration range. Surprisingly, DESI appeared to be a relatively potent 5HT uptake inhibitor. The 5-HT re-uptake system in the pineal probably differes from that in brain tissue. TADs had a marked effect on the metabolism of ³H-5HT in the rat pineal, in an organ culture system, MEL and N-acetylserotonin synthesis increased for the first 11 days and thereafter a slight decrease was observed. HTOH and HIAA also showed an initial increase followed by a slight decrease in synthesis. The synthesis of MTOH and MIAA was decreased. The possibility that TADs could affect HIOMT and SNAT synthesis and thereby change the metabolic pattern of 5-HT was investigated. TADs appeared to stimulate SNAT initially and thereafter a slight decrease from peak activity was observed. This is probably due to stimulation followed by development of subsensitivity of β-receptors, HIOMT activity also appeared to be affected by TADs. The existence of two types of HIOMT is suggested. There is a possibility that these changes in the metabolism of 5-HT could be implicated in the mechanism of action of TADs. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1983
The family
- Authors: Berold, Robert
- Date: 1983
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/460304 , vital:75913 , https://journals.co.za/doi/epdf/10.10520/AJA00284459_394
- Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
- Full Text:
- Date Issued: 1983
- Authors: Berold, Robert
- Date: 1983
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/460304 , vital:75913 , https://journals.co.za/doi/epdf/10.10520/AJA00284459_394
- Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
- Full Text:
- Date Issued: 1983
The geological evolution and mineralised environments of the Tasman Geosyncline
- Authors: Pelham, D A
- Date: 1983 , 2013-04-03
- Subjects: Geosynclines -- Tasmania , Geology -- Tasmania , Ore deposits -- Tasmania , Mineralogy -- Tasmania
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5030 , http://hdl.handle.net/10962/d1006936 , Geosynclines -- Tasmania , Geology -- Tasmania , Ore deposits -- Tasmania , Mineralogy -- Tasmania
- Description: From introduction: The Tasman Geosyncline covers the eastern part of the continent of Australia, an area of over 2 million km'. The area has been a major source of Australian gold and tin production, and though it contains important base metal sulphide deposits, these are overshadowed in scale by the very large stratabound Proterozoic deposits (for example, Mt Isa, Broken Hill and McArthur River). This dissertation deals with the metallic mineral deposits of the Tasman Geosyncline, and as such does not include the extensive post Palaeozoic continental successions, with their important coal reserves, that overlie the deformed geosyncl i nal sequences.
- Full Text:
- Date Issued: 1983
- Authors: Pelham, D A
- Date: 1983 , 2013-04-03
- Subjects: Geosynclines -- Tasmania , Geology -- Tasmania , Ore deposits -- Tasmania , Mineralogy -- Tasmania
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5030 , http://hdl.handle.net/10962/d1006936 , Geosynclines -- Tasmania , Geology -- Tasmania , Ore deposits -- Tasmania , Mineralogy -- Tasmania
- Description: From introduction: The Tasman Geosyncline covers the eastern part of the continent of Australia, an area of over 2 million km'. The area has been a major source of Australian gold and tin production, and though it contains important base metal sulphide deposits, these are overshadowed in scale by the very large stratabound Proterozoic deposits (for example, Mt Isa, Broken Hill and McArthur River). This dissertation deals with the metallic mineral deposits of the Tasman Geosyncline, and as such does not include the extensive post Palaeozoic continental successions, with their important coal reserves, that overlie the deformed geosyncl i nal sequences.
- Full Text:
- Date Issued: 1983
The history of Theopolis Mission, 1814-1851
- Authors: Currie, Marion Rose
- Date: 1983
- Subjects: Barker, George, 1786-1861 , Missions -- South Africa -- Eastern Cape -- History , Khoikhoi (African people) -- History , Xhosa (African people) -- History , Cape of Good Hope (South Africa) -- History -- 1814-1851
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2536 , http://hdl.handle.net/10962/d1002388 , Barker, George, 1786-1861 , Missions -- South Africa -- Eastern Cape -- History , Khoikhoi (African people) -- History , Xhosa (African people) -- History , Cape of Good Hope (South Africa) -- History -- 1814-1851
- Description: This thesis is an investigation of the part played by Theopolis Mission on the Frontier, in the community (both secular and religious)and in the context of race relations. The Journal itself provides the terse, sometimes angry core of commentary on the total situation, and an attempt has been made, by setting it in a broader context, to dispel some of the myths which persist about the role of the Christian missionary, about Khoi Missions (in sharp contast to Xhosa Missions) and about Dr John Phllip. A clear picture has emerged of a people whose life-style, antecedents and history have been inadequately researched in tne period subsequent to 1800.
- Full Text:
- Date Issued: 1983
- Authors: Currie, Marion Rose
- Date: 1983
- Subjects: Barker, George, 1786-1861 , Missions -- South Africa -- Eastern Cape -- History , Khoikhoi (African people) -- History , Xhosa (African people) -- History , Cape of Good Hope (South Africa) -- History -- 1814-1851
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2536 , http://hdl.handle.net/10962/d1002388 , Barker, George, 1786-1861 , Missions -- South Africa -- Eastern Cape -- History , Khoikhoi (African people) -- History , Xhosa (African people) -- History , Cape of Good Hope (South Africa) -- History -- 1814-1851
- Description: This thesis is an investigation of the part played by Theopolis Mission on the Frontier, in the community (both secular and religious)and in the context of race relations. The Journal itself provides the terse, sometimes angry core of commentary on the total situation, and an attempt has been made, by setting it in a broader context, to dispel some of the myths which persist about the role of the Christian missionary, about Khoi Missions (in sharp contast to Xhosa Missions) and about Dr John Phllip. A clear picture has emerged of a people whose life-style, antecedents and history have been inadequately researched in tne period subsequent to 1800.
- Full Text:
- Date Issued: 1983
The London Missionary Society and education
- Authors: George, Ambrose C
- Date: 1983
- Subjects: London Missionary Society -- History Black people -- Education -- South Africa -- Western Cape -- History Missions -- South Africa -- Educational work -- History
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1883 , http://hdl.handle.net/10962/d1005910
- Full Text:
- Date Issued: 1983
- Authors: George, Ambrose C
- Date: 1983
- Subjects: London Missionary Society -- History Black people -- Education -- South Africa -- Western Cape -- History Missions -- South Africa -- Educational work -- History
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1883 , http://hdl.handle.net/10962/d1005910
- Full Text:
- Date Issued: 1983
The origins and subsequent development of Administration Boards
- Authors: Humphries, Richard G
- Date: 1983
- Subjects: South Africa -- Politics and government -- 20th century , Influx control -- South Africa , Public administration -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2854 , http://hdl.handle.net/10962/d1006873 , South Africa -- Politics and government -- 20th century , Influx control -- South Africa , Public administration -- South Africa
- Description: Until the introduction of administration boards in 1972-1973, the responsibility for administering the urban black townships in "white" South Africa was vested with the municipalities as agents of the Department of Bantu Administration and Development. The establishment of administration boards to replace the municipalities' Non-European Affairs Departments reflected the determination of the Department of Bantu Administration and Development to secure tighter direct control over the implementation of policy, particularly that affecting influx control and labour regulation. The decision to end municipal control was made after the report of the Van Rensburg Inter-Departmental Committee of Inquiry into Control Measures, which reported in 1967. The report's concern that influx control was not working as intended, coupled with doubts about the political autonomy of Opposition controlled municipalities, which dated back to the 1950s, were the major reasons for the introduction of administration boards.
- Full Text:
- Date Issued: 1983
- Authors: Humphries, Richard G
- Date: 1983
- Subjects: South Africa -- Politics and government -- 20th century , Influx control -- South Africa , Public administration -- South Africa
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2854 , http://hdl.handle.net/10962/d1006873 , South Africa -- Politics and government -- 20th century , Influx control -- South Africa , Public administration -- South Africa
- Description: Until the introduction of administration boards in 1972-1973, the responsibility for administering the urban black townships in "white" South Africa was vested with the municipalities as agents of the Department of Bantu Administration and Development. The establishment of administration boards to replace the municipalities' Non-European Affairs Departments reflected the determination of the Department of Bantu Administration and Development to secure tighter direct control over the implementation of policy, particularly that affecting influx control and labour regulation. The decision to end municipal control was made after the report of the Van Rensburg Inter-Departmental Committee of Inquiry into Control Measures, which reported in 1967. The report's concern that influx control was not working as intended, coupled with doubts about the political autonomy of Opposition controlled municipalities, which dated back to the 1950s, were the major reasons for the introduction of administration boards.
- Full Text:
- Date Issued: 1983
The parrotfishes of the subfamily Scarinae of the Western Indian Ocean with descriptions of three new species
- Randall, John E, 1924-, Bruce, Robin W
- Authors: Randall, John E, 1924- , Bruce, Robin W
- Date: 1983
- Language: English
- Type: Text
- Identifier: vital:15013 , http://hdl.handle.net/10962/d1019747 , ISSN 0073-4381 , Ichthyological Bulletin of the J.L.B. Smith Institute of Ichthyology; No. 47
- Description: The following 26 previously described species of Parrotfishes of the subfamily Scarinae are found in the Indian Ocean west of the southern tip of India (listed in the parentheses are the range, when restricted to some part of the western Indian Ocean, and junior synonyms not previously documented): Bolbometopon muricatum (Valenciennes) (Callyodon shimoniensis Smith is a synonym); Cetoscarus bicolor (Rüppell) (Scarus roseiceps Valenciennes is a synonym); Hipposcarus harid (Forsskal) [H. longiceps (Valenciennes) is a closely related allopatric species from the Pacific]; Scarus arabicus (Steindachner) (southern Arabian Peninsula and Gulf of Oman; only two specimens known); Scarus capistratoides Bleeker; Scarus caudofasciatus (Gunther) (Callyodon rubrofasciatus Smith is a synonym); Scarus collana Rüppell (a Red Sea endemic; Pseudoscarus ismailius Kossmann and Rauber and S. ghardaqensis Bebars are synonyms); Scarus cyanescens Valenciennes (Pseudoscarus chloromelas Playfair and Gunther is a synonym); Scarus enneacanthus Lacepede; Scarus falcipinnis (Playfair) (Callyodon pindae Smith and C. improvisus Smith are synonyms); Scarus ferrugineus Forsskal (Red Sea and Gulf of Aden; Pseudoscarus augustinus Kossmann and Rauber is a synonym); Scarus festivus Valenciennes (Callyodon lunula Snyder is a synonym); Scarus frenatus Lacepede; Scarus fuscopurpureus (Klunzinger) (Red Sea to Gulf of Oman; Pseudoscarus collana var. eques an Steindachner is a synonym); Scarus ghobban Forsskal (5. lacerta Valenciennes, Callyodon speigleri Smith, and S. fehlmanni Schultz are synonyms), Scarus gibbus Rüppell (Pseudoscarus frontalis Macleay is a synonym and a homonym); Scarus globiceps Valenciennes (S. lepidus Jenyns is a synonym); Scarus niger Forsskal (Pseudoscarus madagascariensis Steindachner is a synonym); Scarus prasiognathos Valenciennes (Maldive Islands appear to the westernmost record; S. chlorodon Jenyns, 5. Singaporensis Bleeker and S. janthochir Bleeker are synonyms); Scarus psittacus Forsskal (5. hertit [Ehrenberg] Valenciennes in C. & V., S. venosus Valenciennes, and S. taeniurus Valenciennes are synonyms); Scarus rubroviolaceus Bleeker (.Pseudoscarus rostratus Gunther is a synonym and a homonym); Scarus russelii Valenciennes (Xanothon fowled Smith is a synonym; initial phase often misidentified as S. venosus)’, Scarus scaber Valenciennes; Scarus sordidus Forsskal (S. spilurus Valenciennes is a synonym, and S. purpureus Valenciennes a synonym and homonym); Scarus tricolor Bleeker (Callyodon mus Smith and C. urbanus Smith are synonyms; initial phase often misidentified as S. Lepidus and the terminal phase as S. pectoralis or S. cyanognathos)’, Scarus viridifucatus (Smith) (Callyodon malindiensis Smith is a synonym), a close relative of S. spinus of the Pacific. Three new species of Scarus are described: S. atrilunula, from Kenya, is in the sordidus complex (initial phase was misidentified as rhoduropterus and the terminal male as capistratoides by Smith, 1956, 1959; S. genazonatus from the Red Sea and Gulf of Aden, also related to S. sordidus, differing chiefly in colour (the most distinctive colour marking of the terminal male is a broad stripe on lower cheek); and S. persicus from the Persian Gulf appears to be related to S. ferrugineus (initial phase light brownish-grey with two rows of small whitish spots on side, and median fin and pelvic fins edged in blue; terminal male similar to that of ferrugineus but with a blackish bar in middle of body). Colour photographs of fresh specimens of all 29 species are presented. Initial and terminal-phase adults are illustrated for most species, and juveniles for some. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1983
- Authors: Randall, John E, 1924- , Bruce, Robin W
- Date: 1983
- Language: English
- Type: Text
- Identifier: vital:15013 , http://hdl.handle.net/10962/d1019747 , ISSN 0073-4381 , Ichthyological Bulletin of the J.L.B. Smith Institute of Ichthyology; No. 47
- Description: The following 26 previously described species of Parrotfishes of the subfamily Scarinae are found in the Indian Ocean west of the southern tip of India (listed in the parentheses are the range, when restricted to some part of the western Indian Ocean, and junior synonyms not previously documented): Bolbometopon muricatum (Valenciennes) (Callyodon shimoniensis Smith is a synonym); Cetoscarus bicolor (Rüppell) (Scarus roseiceps Valenciennes is a synonym); Hipposcarus harid (Forsskal) [H. longiceps (Valenciennes) is a closely related allopatric species from the Pacific]; Scarus arabicus (Steindachner) (southern Arabian Peninsula and Gulf of Oman; only two specimens known); Scarus capistratoides Bleeker; Scarus caudofasciatus (Gunther) (Callyodon rubrofasciatus Smith is a synonym); Scarus collana Rüppell (a Red Sea endemic; Pseudoscarus ismailius Kossmann and Rauber and S. ghardaqensis Bebars are synonyms); Scarus cyanescens Valenciennes (Pseudoscarus chloromelas Playfair and Gunther is a synonym); Scarus enneacanthus Lacepede; Scarus falcipinnis (Playfair) (Callyodon pindae Smith and C. improvisus Smith are synonyms); Scarus ferrugineus Forsskal (Red Sea and Gulf of Aden; Pseudoscarus augustinus Kossmann and Rauber is a synonym); Scarus festivus Valenciennes (Callyodon lunula Snyder is a synonym); Scarus frenatus Lacepede; Scarus fuscopurpureus (Klunzinger) (Red Sea to Gulf of Oman; Pseudoscarus collana var. eques an Steindachner is a synonym); Scarus ghobban Forsskal (5. lacerta Valenciennes, Callyodon speigleri Smith, and S. fehlmanni Schultz are synonyms), Scarus gibbus Rüppell (Pseudoscarus frontalis Macleay is a synonym and a homonym); Scarus globiceps Valenciennes (S. lepidus Jenyns is a synonym); Scarus niger Forsskal (Pseudoscarus madagascariensis Steindachner is a synonym); Scarus prasiognathos Valenciennes (Maldive Islands appear to the westernmost record; S. chlorodon Jenyns, 5. Singaporensis Bleeker and S. janthochir Bleeker are synonyms); Scarus psittacus Forsskal (5. hertit [Ehrenberg] Valenciennes in C. & V., S. venosus Valenciennes, and S. taeniurus Valenciennes are synonyms); Scarus rubroviolaceus Bleeker (.Pseudoscarus rostratus Gunther is a synonym and a homonym); Scarus russelii Valenciennes (Xanothon fowled Smith is a synonym; initial phase often misidentified as S. venosus)’, Scarus scaber Valenciennes; Scarus sordidus Forsskal (S. spilurus Valenciennes is a synonym, and S. purpureus Valenciennes a synonym and homonym); Scarus tricolor Bleeker (Callyodon mus Smith and C. urbanus Smith are synonyms; initial phase often misidentified as S. Lepidus and the terminal phase as S. pectoralis or S. cyanognathos)’, Scarus viridifucatus (Smith) (Callyodon malindiensis Smith is a synonym), a close relative of S. spinus of the Pacific. Three new species of Scarus are described: S. atrilunula, from Kenya, is in the sordidus complex (initial phase was misidentified as rhoduropterus and the terminal male as capistratoides by Smith, 1956, 1959; S. genazonatus from the Red Sea and Gulf of Aden, also related to S. sordidus, differing chiefly in colour (the most distinctive colour marking of the terminal male is a broad stripe on lower cheek); and S. persicus from the Persian Gulf appears to be related to S. ferrugineus (initial phase light brownish-grey with two rows of small whitish spots on side, and median fin and pelvic fins edged in blue; terminal male similar to that of ferrugineus but with a blackish bar in middle of body). Colour photographs of fresh specimens of all 29 species are presented. Initial and terminal-phase adults are illustrated for most species, and juveniles for some. , Rhodes University Libraries (Digitisation)
- Full Text:
- Date Issued: 1983
The question of validity in Vasari's art historical concept
- Authors: Gibb, Barry
- Date: 1983
- Subjects: Vasari, Giorgio, 1511-1574 -- Criticism and interpretation
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2465 , http://hdl.handle.net/10962/d1008574
- Description: From Introduction: Giorgio Vasari's first and second editions of his 'Lives of the Artists I appeared respectively in 1550 and 1568, just after the great period of Renaissance art in Florence and Rome had ended. As a practising Florentine architect, painter and sculptor who travelled extensively in Italy, sari could write with authority on the development of these arts throughout what he saw ~s the whole Renaissance period in that country, from the l ate 13th to the mid-16th century. Gathering information from all possible sources, his 'Lives' constitute the first comprehensive historical - critical survey of Italian Renaissance art. Much of their value resides in the first hand information they contain concerning the artists (Michelangelo in particular) who were his contemporaries, and in reflecting the aesthetic attitudes prevalent in a peak period in the history of art.
- Full Text:
- Date Issued: 1983
- Authors: Gibb, Barry
- Date: 1983
- Subjects: Vasari, Giorgio, 1511-1574 -- Criticism and interpretation
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2465 , http://hdl.handle.net/10962/d1008574
- Description: From Introduction: Giorgio Vasari's first and second editions of his 'Lives of the Artists I appeared respectively in 1550 and 1568, just after the great period of Renaissance art in Florence and Rome had ended. As a practising Florentine architect, painter and sculptor who travelled extensively in Italy, sari could write with authority on the development of these arts throughout what he saw ~s the whole Renaissance period in that country, from the l ate 13th to the mid-16th century. Gathering information from all possible sources, his 'Lives' constitute the first comprehensive historical - critical survey of Italian Renaissance art. Much of their value resides in the first hand information they contain concerning the artists (Michelangelo in particular) who were his contemporaries, and in reflecting the aesthetic attitudes prevalent in a peak period in the history of art.
- Full Text:
- Date Issued: 1983
The relationship between psychological androgyny and attitudes towards women, self-actualization, and concepts of adjustment
- Authors: Finlay, Helen Ann
- Date: 1983
- Subjects: Androgyny (Psychology) , Sex differences (Psychology) , Self-actualization (Psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3139 , http://hdl.handle.net/10962/d1006964 , Androgyny (Psychology) , Sex differences (Psychology) , Self-actualization (Psychology)
- Description: In accordance with American findings, it was proposed that androgynous individuals would be more liberal in their attitudes towards women and more self-actualizing than sex-typed individuals, and that they would tend to conceptualize the well-adjusted person as androgynous, while the sex-typed individual would tend to conceptualize such a person as masculine. It was further hypothesized that sex differences in favour of the female subjects would be found on the first two variables. The Bern Sex-Role Inventory, Shostrom's Personal Orientation Inventory and Spence and Helmreich's Attitudes Toward Women Scale were applied to 192 school counsellors in training and in the field. The hypotheses regarding an androgynous as opposed to a sex-typed orientation on the variables attitudes toward women and self-actualization were not supported; nor were sex-typed individuals found to conceptualize a well-adjusted person as masculine . Sex differences in favour of female subjects were found on the Attitudes Toward Women Scale and on some of the Personal Orientation Inventory scales, and androgynous subjects were found to hold an androgynous model of adjustment.
- Full Text:
- Date Issued: 1983
- Authors: Finlay, Helen Ann
- Date: 1983
- Subjects: Androgyny (Psychology) , Sex differences (Psychology) , Self-actualization (Psychology)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3139 , http://hdl.handle.net/10962/d1006964 , Androgyny (Psychology) , Sex differences (Psychology) , Self-actualization (Psychology)
- Description: In accordance with American findings, it was proposed that androgynous individuals would be more liberal in their attitudes towards women and more self-actualizing than sex-typed individuals, and that they would tend to conceptualize the well-adjusted person as androgynous, while the sex-typed individual would tend to conceptualize such a person as masculine. It was further hypothesized that sex differences in favour of the female subjects would be found on the first two variables. The Bern Sex-Role Inventory, Shostrom's Personal Orientation Inventory and Spence and Helmreich's Attitudes Toward Women Scale were applied to 192 school counsellors in training and in the field. The hypotheses regarding an androgynous as opposed to a sex-typed orientation on the variables attitudes toward women and self-actualization were not supported; nor were sex-typed individuals found to conceptualize a well-adjusted person as masculine . Sex differences in favour of female subjects were found on the Attitudes Toward Women Scale and on some of the Personal Orientation Inventory scales, and androgynous subjects were found to hold an androgynous model of adjustment.
- Full Text:
- Date Issued: 1983
The significance of unconformities in the development of Witwatersrand gold and uranium placers
- Authors: Beater, Christian Douglas
- Date: 1983 , 2013-04-03
- Subjects: Placer deposits , Gold ores -- Geology -- South Africa -- Witwatersrand , Uranium ores -- Geology -- South Africa -- Witwatersrand
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4925 , http://hdl.handle.net/10962/d1004535 , Placer deposits , Gold ores -- Geology -- South Africa -- Witwatersrand , Uranium ores -- Geology -- South Africa -- Witwatersrand
- Description: Most of the economic gold and uranium placers are developed on low angle disconformities in the Central Rand Group and concentrations of gold and uranium are usually at their optimum on unconformity surfaces. Examples include the Kimberley Reef and South Reef of the East Rand, the Main Reef Leader of the Central Rand, the Carbon Leader of the Carletonville goldfield, the Vaal Reef of the Klerksdorp goldfield and the Basal/Steyn placers of the Welkom goldfield. The individual goldfields represent fluvial fans which are composed of a large number of tectonogenetic sedimentary packages separated by unconformities. The tectonic responses between cycles of sedimentation produced unconformities and tectonically controlled cyclic sedimentation is one of the key factors culminating in the preparation and deposition of auriferous placers within the Witwatersrand succession. Unconformities, which represent breaks in sedimentation, result in the preconditioning of palaeosurfaces and redistribution of sediments and heavy minerals on them. Winnowing of sands produced heavy mineral residual accumulations on erosion surfaces which were generally preserved by small-pebble lags or algal mats. Reworking of units truncated by the unconformities provided additional gold, uranium and heavy minerals to unconformity surfaces.
- Full Text:
- Date Issued: 1983
- Authors: Beater, Christian Douglas
- Date: 1983 , 2013-04-03
- Subjects: Placer deposits , Gold ores -- Geology -- South Africa -- Witwatersrand , Uranium ores -- Geology -- South Africa -- Witwatersrand
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4925 , http://hdl.handle.net/10962/d1004535 , Placer deposits , Gold ores -- Geology -- South Africa -- Witwatersrand , Uranium ores -- Geology -- South Africa -- Witwatersrand
- Description: Most of the economic gold and uranium placers are developed on low angle disconformities in the Central Rand Group and concentrations of gold and uranium are usually at their optimum on unconformity surfaces. Examples include the Kimberley Reef and South Reef of the East Rand, the Main Reef Leader of the Central Rand, the Carbon Leader of the Carletonville goldfield, the Vaal Reef of the Klerksdorp goldfield and the Basal/Steyn placers of the Welkom goldfield. The individual goldfields represent fluvial fans which are composed of a large number of tectonogenetic sedimentary packages separated by unconformities. The tectonic responses between cycles of sedimentation produced unconformities and tectonically controlled cyclic sedimentation is one of the key factors culminating in the preparation and deposition of auriferous placers within the Witwatersrand succession. Unconformities, which represent breaks in sedimentation, result in the preconditioning of palaeosurfaces and redistribution of sediments and heavy minerals on them. Winnowing of sands produced heavy mineral residual accumulations on erosion surfaces which were generally preserved by small-pebble lags or algal mats. Reworking of units truncated by the unconformities provided additional gold, uranium and heavy minerals to unconformity surfaces.
- Full Text:
- Date Issued: 1983
The theory of the firm and pricing behaviour in South African manufacturing industry
- Authors: Dollery, Brian
- Date: 1983
- Subjects: Corporations Pricing Pricing -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1046 , http://hdl.handle.net/10962/d1006141
- Full Text:
- Date Issued: 1983
- Authors: Dollery, Brian
- Date: 1983
- Subjects: Corporations Pricing Pricing -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1046 , http://hdl.handle.net/10962/d1006141
- Full Text:
- Date Issued: 1983
The thermodynamics of binary liquid mixtures
- Scoones, Brett Warren Hamilton
- Authors: Scoones, Brett Warren Hamilton
- Date: 1983 , 2013-03-15
- Subjects: Thermodynamics , Thermodynamics -- Tables , Solution (Chemistry) , Liquids
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4392 , http://hdl.handle.net/10962/d1005893 , Thermodynamics , Thermodynamics -- Tables , Solution (Chemistry) , Liquids
- Description: A systematic study of the excess thermodynamic properties of two-ring compounds and n-alkanes was conducted. The excess enthalpies were determined at 288,15 K and 298,15 K by using a flow microcalorimetric technique. The excess volumes of tetralin and cycloalkanes, and tetralin and --alkans at 288,15 K and 298,15 K were determined by using a vibrating tube densitometer. The results showed trends relating to the size and shape of the n-alkane and cycloalkan molecules. The theory developed by Flory was applied to the decalin + cycloalkane and + n-alkane systems and this gave qualitative predictions of the excess enthalpies from the excess volumes and vice versa. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1983
- Authors: Scoones, Brett Warren Hamilton
- Date: 1983 , 2013-03-15
- Subjects: Thermodynamics , Thermodynamics -- Tables , Solution (Chemistry) , Liquids
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4392 , http://hdl.handle.net/10962/d1005893 , Thermodynamics , Thermodynamics -- Tables , Solution (Chemistry) , Liquids
- Description: A systematic study of the excess thermodynamic properties of two-ring compounds and n-alkanes was conducted. The excess enthalpies were determined at 288,15 K and 298,15 K by using a flow microcalorimetric technique. The excess volumes of tetralin and cycloalkanes, and tetralin and --alkans at 288,15 K and 298,15 K were determined by using a vibrating tube densitometer. The results showed trends relating to the size and shape of the n-alkane and cycloalkan molecules. The theory developed by Flory was applied to the decalin + cycloalkane and + n-alkane systems and this gave qualitative predictions of the excess enthalpies from the excess volumes and vice versa. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1983
The timing of breeding and wing‐moult of four African Sturnidae
- Authors: Craig, Adrian J F K
- Date: 1983
- Subjects: To be catalogued
- Language: English
- Type: article
- Identifier: http://hdl.handle.net/10962/465549 , vital:76619 , https://doi.org/10.1111/j.1474-919X.1983.tb03120.x
- Description: Wing‐moult of the Cape Glossy Starling, Red‐winged Starling, Pale‐winged Starling and Pied Starling was examined primarily from speci-mens in southern African museums. Breeding data were obtained from nest record cards. The Cape Glossy Starling breeds from October to March, with the moult period from December to May. There is no evi-dence of moult‐breeding overlap in individual birds. The Red‐winged Starling breeds from September to March, while the moult takes place between November and April, overlapping with the second broods. The Pale‐winged Starling breeds from October to April and moults between November and May. The Pied Starling moults between November and April, while breeding varies regionally, occurring concurrently with moulting in some areas.
- Full Text:
- Date Issued: 1983
- Authors: Craig, Adrian J F K
- Date: 1983
- Subjects: To be catalogued
- Language: English
- Type: article
- Identifier: http://hdl.handle.net/10962/465549 , vital:76619 , https://doi.org/10.1111/j.1474-919X.1983.tb03120.x
- Description: Wing‐moult of the Cape Glossy Starling, Red‐winged Starling, Pale‐winged Starling and Pied Starling was examined primarily from speci-mens in southern African museums. Breeding data were obtained from nest record cards. The Cape Glossy Starling breeds from October to March, with the moult period from December to May. There is no evi-dence of moult‐breeding overlap in individual birds. The Red‐winged Starling breeds from September to March, while the moult takes place between November and April, overlapping with the second broods. The Pale‐winged Starling breeds from October to April and moults between November and May. The Pied Starling moults between November and April, while breeding varies regionally, occurring concurrently with moulting in some areas.
- Full Text:
- Date Issued: 1983
The verdict
- Authors: Berold, Robert
- Date: 1983
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/460316 , vital:75914 , https://journals.co.za/doi/epdf/10.10520/AJA00284459_394
- Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
- Full Text:
- Date Issued: 1983
- Authors: Berold, Robert
- Date: 1983
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/460316 , vital:75914 , https://journals.co.za/doi/epdf/10.10520/AJA00284459_394
- Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
- Full Text:
- Date Issued: 1983
Title Not Specified
- Congregation at Lourdes Mission, Composer Not Specified, Dargie, Dave
- Authors: Congregation at Lourdes Mission , Composer Not Specified , Dargie, Dave
- Date: 1983
- Subjects: Folk music , Folk songs, Xhosa , Field recordings , Africa, Sub-Saharan , Africa South Africa Lourdes Mission f-sa
- Language: Zulu
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/286761 , vital:56312 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DD073-06
- Description: Ordination of Father P. Manci.
- Full Text: false
- Date Issued: 1983
- Authors: Congregation at Lourdes Mission , Composer Not Specified , Dargie, Dave
- Date: 1983
- Subjects: Folk music , Folk songs, Xhosa , Field recordings , Africa, Sub-Saharan , Africa South Africa Lourdes Mission f-sa
- Language: Zulu
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/286761 , vital:56312 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DD073-06
- Description: Ordination of Father P. Manci.
- Full Text: false
- Date Issued: 1983