A geohydrological evaluation of the coastal area between Bushmans River Mouth and Cape Mouth and Cape Padrone, Eastern Cape, South Africa
- Authors: Jolly, J L
- Date: 1984 , 2013-03-15
- Subjects: Hydrogeology -- South Africa -- Eastern Cape , Coastal zone management -- South Africa -- Eastern Cape , Coastal ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4859 , http://hdl.handle.net/10962/d1005635 , Hydrogeology -- South Africa -- Eastern Cape , Coastal zone management -- South Africa -- Eastern Cape , Coastal ecology -- South Africa -- Eastern Cape
- Full Text:
- Date Issued: 1984
- Authors: Jolly, J L
- Date: 1984 , 2013-03-15
- Subjects: Hydrogeology -- South Africa -- Eastern Cape , Coastal zone management -- South Africa -- Eastern Cape , Coastal ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4859 , http://hdl.handle.net/10962/d1005635 , Hydrogeology -- South Africa -- Eastern Cape , Coastal zone management -- South Africa -- Eastern Cape , Coastal ecology -- South Africa -- Eastern Cape
- Full Text:
- Date Issued: 1984
An evaluation of Mimorista pulchellalis (Dyar) (Lepidoptera : Pyraustidae) as a biocontrol agent against jointed cactus in South Africa
- Authors: Nieman, Erik
- Date: 1984
- Subjects: Cactus -- South Africa , Weeds -- Biological control -- South Africa , Pyralidae -- South Africa , Moths -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5812 , http://hdl.handle.net/10962/d1007052 , Cactus -- South Africa , Weeds -- Biological control -- South Africa , Pyralidae -- South Africa , Moths -- South Africa
- Description: From the introduction: The work on Mimorista is divided into two sections: a laboratory orientated study which describes the biology and rearing techniques and a field orientated study where the establishment of the insect and its impact on jointed cactus populations are examined. In the final chapters the integration of this insect in the current control program are discussed and recommendations regarding its future in South Africa are given.
- Full Text:
- Date Issued: 1984
- Authors: Nieman, Erik
- Date: 1984
- Subjects: Cactus -- South Africa , Weeds -- Biological control -- South Africa , Pyralidae -- South Africa , Moths -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5812 , http://hdl.handle.net/10962/d1007052 , Cactus -- South Africa , Weeds -- Biological control -- South Africa , Pyralidae -- South Africa , Moths -- South Africa
- Description: From the introduction: The work on Mimorista is divided into two sections: a laboratory orientated study which describes the biology and rearing techniques and a field orientated study where the establishment of the insect and its impact on jointed cactus populations are examined. In the final chapters the integration of this insect in the current control program are discussed and recommendations regarding its future in South Africa are given.
- Full Text:
- Date Issued: 1984
An investigation of the groundwater seepage and irrigation return flow of the Middleton area of the Great Fish River
- Authors: Reynders, Anthony Gerard
- Date: 1984 , 2013-04-11
- Subjects: Irrigation -- South Africa -- Great Fish River , Seepage , Groundwater flow -- South Africa -- Great Fish River
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5035 , http://hdl.handle.net/10962/d1007380 , Irrigation -- South Africa -- Great Fish River , Seepage , Groundwater flow -- South Africa -- Great Fish River
- Description: From introduction: This study is concerned with the factors responsible for mineralisation of water in the Great Fish River, in particular the irrigation return flow and groundwater seepage components. A small irrigated area in the lower Fish River Basin was chosen for a detailed study of irrigation water input, groundwater and seepage water fluctuati ons, and the affect of soils and rocks on river water mineralisation. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
- Authors: Reynders, Anthony Gerard
- Date: 1984 , 2013-04-11
- Subjects: Irrigation -- South Africa -- Great Fish River , Seepage , Groundwater flow -- South Africa -- Great Fish River
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5035 , http://hdl.handle.net/10962/d1007380 , Irrigation -- South Africa -- Great Fish River , Seepage , Groundwater flow -- South Africa -- Great Fish River
- Description: From introduction: This study is concerned with the factors responsible for mineralisation of water in the Great Fish River, in particular the irrigation return flow and groundwater seepage components. A small irrigated area in the lower Fish River Basin was chosen for a detailed study of irrigation water input, groundwater and seepage water fluctuati ons, and the affect of soils and rocks on river water mineralisation. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
Analytical procedures for the determination of wattle polyphenols in wastewaters
- Authors: Hendry, Antony John
- Date: 1984
- Subjects: Liquid chromatography , Spectrophotometry , High performance liquid chromatography , Water -- Purification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4431 , http://hdl.handle.net/10962/d1007221 , Liquid chromatography , Spectrophotometry , High performance liquid chromatography , Water -- Purification
- Full Text:
- Date Issued: 1984
- Authors: Hendry, Antony John
- Date: 1984
- Subjects: Liquid chromatography , Spectrophotometry , High performance liquid chromatography , Water -- Purification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4431 , http://hdl.handle.net/10962/d1007221 , Liquid chromatography , Spectrophotometry , High performance liquid chromatography , Water -- Purification
- Full Text:
- Date Issued: 1984
Aspects of the ecology of the shrimp Palaemon pacificus (Stimpson) (Decapoda,Palaemonidae) in the Bushmans river estuary
- Authors: Robertson, Wendy Daryl
- Date: 1984
- Subjects: Shrimps -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5815 , http://hdl.handle.net/10962/d1007184 , Shrimps -- South Africa
- Description: The recruitment of Palaemon pacificus to the Bushmans River estuary was studied over a 12 month period. The dynamics of a population of shrimps in a small, tidal channel in the lower reaches of the estuary was investigated over a similar time span. Temperature and salinity tolerances of various stages and sizes of shrimps were compared in controlled experiments and are discussed in the light of the distribution and general ecology of the shrimp. Stage 6 zoeae and post-larvae entered the estuary on nocturnal flood tides throughout the year with peak recruitment occurring in March/April. The population of shrimps in the study site was predominantly juvenile for most of the year, with peak sub-adult numbers occurring in midsummer. The sex ratio was female-biased throughout the year except for short bursts of male predominance in February and April. Average growth rate was 0,043 mm carapace length per day. Maximum residence time in the study site was estimated to be four months and in the estuary at least six months. Flooding of the estuary resulted in a considerable reduction in juvenile numbers in the study site and some loss of sub-adults. Shrimps tolerated a temperature range of 4,3 to 30,9⁰C for 144 hours. Their long term tolerance range is probably narrower (10 to 28⁰C) because of the effects of temperature related factors such as starvation and disease. Their distribution in South Africa (Olifants River to Kosi Bay ) is consistent with this tolerance range. Sub-adults tolerated salinities of 1 to 79 ‰ and post-larvae 2 to 60 ‰ at 15⁰C for 144 hours. Low moulting success (low and high salinities ) and starvation (high salinities) would probably reduce these tolerance ranges to 2 to 56 ‰ (sub-adults) and 4 to 56 ‰ (post-larvae). Higher and lower temperatures (10 and 20⁰C) reduced the tolerance of post-larvae to low salinities, but sub-adults were only affected at 30⁰C. Stages 4 and 5 and stage 6 zoeae were intolerant of salinities below 14 ‰. The development of salinity tolerance with age is consistent with the retention of a marine breeding phase. It also explains the high loss of juveniles from the study site following the flood. It is postulated that recovery of the population after a flood would be fairly rapid except in extreme cases when estuarine vegetation is severely affected.
- Full Text:
- Date Issued: 1984
- Authors: Robertson, Wendy Daryl
- Date: 1984
- Subjects: Shrimps -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5815 , http://hdl.handle.net/10962/d1007184 , Shrimps -- South Africa
- Description: The recruitment of Palaemon pacificus to the Bushmans River estuary was studied over a 12 month period. The dynamics of a population of shrimps in a small, tidal channel in the lower reaches of the estuary was investigated over a similar time span. Temperature and salinity tolerances of various stages and sizes of shrimps were compared in controlled experiments and are discussed in the light of the distribution and general ecology of the shrimp. Stage 6 zoeae and post-larvae entered the estuary on nocturnal flood tides throughout the year with peak recruitment occurring in March/April. The population of shrimps in the study site was predominantly juvenile for most of the year, with peak sub-adult numbers occurring in midsummer. The sex ratio was female-biased throughout the year except for short bursts of male predominance in February and April. Average growth rate was 0,043 mm carapace length per day. Maximum residence time in the study site was estimated to be four months and in the estuary at least six months. Flooding of the estuary resulted in a considerable reduction in juvenile numbers in the study site and some loss of sub-adults. Shrimps tolerated a temperature range of 4,3 to 30,9⁰C for 144 hours. Their long term tolerance range is probably narrower (10 to 28⁰C) because of the effects of temperature related factors such as starvation and disease. Their distribution in South Africa (Olifants River to Kosi Bay ) is consistent with this tolerance range. Sub-adults tolerated salinities of 1 to 79 ‰ and post-larvae 2 to 60 ‰ at 15⁰C for 144 hours. Low moulting success (low and high salinities ) and starvation (high salinities) would probably reduce these tolerance ranges to 2 to 56 ‰ (sub-adults) and 4 to 56 ‰ (post-larvae). Higher and lower temperatures (10 and 20⁰C) reduced the tolerance of post-larvae to low salinities, but sub-adults were only affected at 30⁰C. Stages 4 and 5 and stage 6 zoeae were intolerant of salinities below 14 ‰. The development of salinity tolerance with age is consistent with the retention of a marine breeding phase. It also explains the high loss of juveniles from the study site following the flood. It is postulated that recovery of the population after a flood would be fairly rapid except in extreme cases when estuarine vegetation is severely affected.
- Full Text:
- Date Issued: 1984
Calibration and interpretation of A 2.3 GHz continuum survey
- Authors: Greybe, Andrew
- Date: 1984
- Subjects: Radio astronomy , Astronomical observatories , Galaxies
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5502 , http://hdl.handle.net/10962/d1007210 , Radio astronomy , Astronomical observatories , Galaxies
- Description: This thesis continues the Rhodes 2.3 GHz Survey of the Southern Sky. It consists of two parts : a data processing part and an astronomical analysis part. In the data processing part the data for the regions 4HR to 15HR, -80° to -61° and 12HR to 23HR . -27° to -7° are presented in contour map format. A beam pattern of the Hartebeesthoek telescope at 13 cm is constructed from drift scans of the radio source TAU A. This is used to investigate the data filtering techniques applied to the Rhodes Survey. It is proposed that a set of widely spaced scans which have been referred to the South Celestial Pole can provide a single calibrated baselevel for the Rhodes Survey. The observing technique and the necessary reduction programs to create a coarse grid of antenna temperatures of the Southern Sky using these observation are developed. Preliminary results for this technique are presented as a map of the region 18HR to 6HR, 90° to 30° with a 5°x5° resolution. On the astronomical side two studies are undertaken. The region 13HR to 23HR, -61° to -7° is searched for large extended areas of emission. 7 features occurring at intermediate galactic latitudes are found. They are interpreted as follows: one of them is the classical HII region surrounding the star Zeta Ophiuchi (l",b")=(6.7°,22.4°), and the rest are combinations of thermal and nonthermal emission from galactic features. The galactic equator profile for 24°> L > -58° is studied. It is dominated by a plateau of emission for L < -26°. This is interpreted as a combination of thermal and nonthermal radiation emitted by a ring of gas symmetric about the galactic centre with a radius of 4 - 6 kpc.
- Full Text:
- Date Issued: 1984
- Authors: Greybe, Andrew
- Date: 1984
- Subjects: Radio astronomy , Astronomical observatories , Galaxies
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5502 , http://hdl.handle.net/10962/d1007210 , Radio astronomy , Astronomical observatories , Galaxies
- Description: This thesis continues the Rhodes 2.3 GHz Survey of the Southern Sky. It consists of two parts : a data processing part and an astronomical analysis part. In the data processing part the data for the regions 4HR to 15HR, -80° to -61° and 12HR to 23HR . -27° to -7° are presented in contour map format. A beam pattern of the Hartebeesthoek telescope at 13 cm is constructed from drift scans of the radio source TAU A. This is used to investigate the data filtering techniques applied to the Rhodes Survey. It is proposed that a set of widely spaced scans which have been referred to the South Celestial Pole can provide a single calibrated baselevel for the Rhodes Survey. The observing technique and the necessary reduction programs to create a coarse grid of antenna temperatures of the Southern Sky using these observation are developed. Preliminary results for this technique are presented as a map of the region 18HR to 6HR, 90° to 30° with a 5°x5° resolution. On the astronomical side two studies are undertaken. The region 13HR to 23HR, -61° to -7° is searched for large extended areas of emission. 7 features occurring at intermediate galactic latitudes are found. They are interpreted as follows: one of them is the classical HII region surrounding the star Zeta Ophiuchi (l",b")=(6.7°,22.4°), and the rest are combinations of thermal and nonthermal emission from galactic features. The galactic equator profile for 24°> L > -58° is studied. It is dominated by a plateau of emission for L < -26°. This is interpreted as a combination of thermal and nonthermal radiation emitted by a ring of gas symmetric about the galactic centre with a radius of 4 - 6 kpc.
- Full Text:
- Date Issued: 1984
Design automation of a machine-independent code generator
- Authors: Clayton, Peter Graham
- Date: 1984 , 2013-01-22
- Subjects: Compilers (Computer programs) , Programming languages (Electronic computers)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4676 , http://hdl.handle.net/10962/d1006699 , Compilers (Computer programs) , Programming languages (Electronic computers)
- Description: As both computer languages and architectures continue to proliferate, there is a continuing need for new compilers. Researchers have attempted to ease the work of producing compilers by developing methods to automate compiler writing. While much work has been done (and considerable success achieved) in writing parsers which can handle a variety of source languages (using mainly table-driven analysis methods), less progress has been made in formalizing the code generation end of the compiler. Nevertheless, some of the more recent publications in code generation stress portability or retargetability of the resulting compiler. A number of code generator synthesisers have been developed, some of which produce code that can be compared in quality with that produced by a conventional code generator. However, because of the complexity of generalizing the mapping from source language to target machine, and the need for efficiency of various kinds, code generator synthesisers are large, complicated programs. Consequently, the person who develops a code generator using one of these tools invariably needs to be a code generation specialist himself. Many compilers follow a pattern of having a front end which generates intermediate code, and a back end which converts intermediate code to machine code. The intermediate code is effectively machine independent, or can be designed that way. With these points in mind, we have set out to write a system of programs which -- 1. will allow the generation of such a back end in a reasonably short time, for a general intermediate code, and for a general machine code, and -- 2. can be used by anyone who has a sound knowledge of the target machine's architecture and associated assembler language, but is not necessarily a specialist compiler writer. The system consists of a series of friendly, interactive programs by means of which the user sets up tables defining the architecture and assembly level instructions for the target machine, and the code templates onto which intermediate codes produced by a parser have been mapped. A general notation has been developed to represent machine instructions using the same format as the target assembler. Thus the code generator writer is able to write code sequences to perform the effects of the intermediate codes, using assembly mnemonics familiar to him. The resultant table-driven code generator simply replaces a sequence of intermediate codes by their respective code templates, relocating them in memory and filling in addresses known only at code-generation time. This thesis describes the use and implementation details of this generalized code generation system. As an example, the implementation of a code generator for a CLANG [23] parser on an 8080 processor is described. The discussion also includes guide-lines on how to implement a loader and associated run-time routines for use in executing the object code. The results of a number of bench-marks have shown, as expected, that code produced by a code generator developed in this manner is larger and slower than that from a special purpose optimizing code generator, but is still several times faster than interpreting the intermediate code. The major benefit to be gained from using this system lies in the shorter development time by a less skilled person. , KMBT_223 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
- Authors: Clayton, Peter Graham
- Date: 1984 , 2013-01-22
- Subjects: Compilers (Computer programs) , Programming languages (Electronic computers)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4676 , http://hdl.handle.net/10962/d1006699 , Compilers (Computer programs) , Programming languages (Electronic computers)
- Description: As both computer languages and architectures continue to proliferate, there is a continuing need for new compilers. Researchers have attempted to ease the work of producing compilers by developing methods to automate compiler writing. While much work has been done (and considerable success achieved) in writing parsers which can handle a variety of source languages (using mainly table-driven analysis methods), less progress has been made in formalizing the code generation end of the compiler. Nevertheless, some of the more recent publications in code generation stress portability or retargetability of the resulting compiler. A number of code generator synthesisers have been developed, some of which produce code that can be compared in quality with that produced by a conventional code generator. However, because of the complexity of generalizing the mapping from source language to target machine, and the need for efficiency of various kinds, code generator synthesisers are large, complicated programs. Consequently, the person who develops a code generator using one of these tools invariably needs to be a code generation specialist himself. Many compilers follow a pattern of having a front end which generates intermediate code, and a back end which converts intermediate code to machine code. The intermediate code is effectively machine independent, or can be designed that way. With these points in mind, we have set out to write a system of programs which -- 1. will allow the generation of such a back end in a reasonably short time, for a general intermediate code, and for a general machine code, and -- 2. can be used by anyone who has a sound knowledge of the target machine's architecture and associated assembler language, but is not necessarily a specialist compiler writer. The system consists of a series of friendly, interactive programs by means of which the user sets up tables defining the architecture and assembly level instructions for the target machine, and the code templates onto which intermediate codes produced by a parser have been mapped. A general notation has been developed to represent machine instructions using the same format as the target assembler. Thus the code generator writer is able to write code sequences to perform the effects of the intermediate codes, using assembly mnemonics familiar to him. The resultant table-driven code generator simply replaces a sequence of intermediate codes by their respective code templates, relocating them in memory and filling in addresses known only at code-generation time. This thesis describes the use and implementation details of this generalized code generation system. As an example, the implementation of a code generator for a CLANG [23] parser on an 8080 processor is described. The discussion also includes guide-lines on how to implement a loader and associated run-time routines for use in executing the object code. The results of a number of bench-marks have shown, as expected, that code produced by a code generator developed in this manner is larger and slower than that from a special purpose optimizing code generator, but is still several times faster than interpreting the intermediate code. The major benefit to be gained from using this system lies in the shorter development time by a less skilled person. , KMBT_223 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
Investigations into the dietary requirements of Clarias gariepinus larvae (Pisces : Clariidae) and the formulation and manufacture of an artificial dry feed for use in intensive larval rearing
- Authors: Uys, Wynand
- Date: 1984
- Subjects: Clarias gariepinus Catfishes -- Africa Clariidae Catfishes -- Africa -- Nutrition -- Requirements Clarias
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5205 , http://hdl.handle.net/10962/d1004446
- Description: The need for developing an artificial dry feed for Clarias gariepinus larvae was identified. Dry larval fishfeed requires certain physical properties. Techniques for manufacturing feeds which comply with these requirements were evolved and are recomended for practical use. The techniques that were used for artificial reproduction of C. gariepinus larvae are briefly discussed. The larvae were fed on various dietary formulations and their growth responses were monitored in order to determine their nutritional requirements. A feed was developed which gave superior results to those obtained with natural food organisms. This feed consisted of Torula yeast(69,8%), fishmeal(23,3%), vitamin supplements(O,9%), methionine supplement (150mg/kg), bactericide and preservatives. The feed particles were coated with a lipid supplement which was added at a ratio of 6% to the weight of the feed. The optimum particle size (diameter) for C. gariepinus larvae is 2,2% of their mean total length. The larvae should be given a feed ration of 25% of body weight per day at a frequency of once every four hours. A favourable feed conversion ratio of 1.1g of feed consumed per gram of larval weight gain was experienced. The established dry feed is suitable for use in commercial hatcheries and can be used as a standard and proven food source for further research on the intensive rearing of C. gariepinus larvae.
- Full Text:
- Date Issued: 1984
- Authors: Uys, Wynand
- Date: 1984
- Subjects: Clarias gariepinus Catfishes -- Africa Clariidae Catfishes -- Africa -- Nutrition -- Requirements Clarias
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5205 , http://hdl.handle.net/10962/d1004446
- Description: The need for developing an artificial dry feed for Clarias gariepinus larvae was identified. Dry larval fishfeed requires certain physical properties. Techniques for manufacturing feeds which comply with these requirements were evolved and are recomended for practical use. The techniques that were used for artificial reproduction of C. gariepinus larvae are briefly discussed. The larvae were fed on various dietary formulations and their growth responses were monitored in order to determine their nutritional requirements. A feed was developed which gave superior results to those obtained with natural food organisms. This feed consisted of Torula yeast(69,8%), fishmeal(23,3%), vitamin supplements(O,9%), methionine supplement (150mg/kg), bactericide and preservatives. The feed particles were coated with a lipid supplement which was added at a ratio of 6% to the weight of the feed. The optimum particle size (diameter) for C. gariepinus larvae is 2,2% of their mean total length. The larvae should be given a feed ration of 25% of body weight per day at a frequency of once every four hours. A favourable feed conversion ratio of 1.1g of feed consumed per gram of larval weight gain was experienced. The established dry feed is suitable for use in commercial hatcheries and can be used as a standard and proven food source for further research on the intensive rearing of C. gariepinus larvae.
- Full Text:
- Date Issued: 1984
Protection from beetle-predation in cochineal insects (Dactylopiidae : Homoptera)
- Authors: Morrison, John Frederick
- Date: 1984
- Subjects: Cochineal insect , Homoptera
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5819 , http://hdl.handle.net/10962/d1007282 , Cochineal insect , Homoptera
- Description: From introduction: In South Africa the native ladybird beetle Exochomus flaviventris Mader feeds on the introduced cochineal insect Dactylopius opuntiae (Cockerell) (Pettey, 1943, 1946, 1948; Geyer, 1947 a, b; Pettey and Marais, 1950). It has also been reported to feed on Dactylopius austrinus Lindley (Geyer, 1947 a; Pettey, 1948), but this appears to occur rarely in the field (H.G. Zimmermann and H.G. Robertson pers. camm. ; Appendix 1 ). This thesis attempts to determine why E. flaviventris feeds on D. opuntiae in the field but not on D. austrinus.
- Full Text:
- Date Issued: 1984
- Authors: Morrison, John Frederick
- Date: 1984
- Subjects: Cochineal insect , Homoptera
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5819 , http://hdl.handle.net/10962/d1007282 , Cochineal insect , Homoptera
- Description: From introduction: In South Africa the native ladybird beetle Exochomus flaviventris Mader feeds on the introduced cochineal insect Dactylopius opuntiae (Cockerell) (Pettey, 1943, 1946, 1948; Geyer, 1947 a, b; Pettey and Marais, 1950). It has also been reported to feed on Dactylopius austrinus Lindley (Geyer, 1947 a; Pettey, 1948), but this appears to occur rarely in the field (H.G. Zimmermann and H.G. Robertson pers. camm. ; Appendix 1 ). This thesis attempts to determine why E. flaviventris feeds on D. opuntiae in the field but not on D. austrinus.
- Full Text:
- Date Issued: 1984
Serotonin binding in vitro by releasable proteins from human blood platelets
- Authors: Heemstra, Valerie Lawrence
- Date: 1984 , 2013-04-10
- Subjects: Serotonin , Serotonin -- Metabolism
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3829 , http://hdl.handle.net/10962/d1007215 , Serotonin , Serotonin -- Metabolism
- Description: Among the substances released from human blood platelets are serotonin and various proteins. It was hypothesized that one of these proteins binds serotonin and that serotonin might be important to the protein's function or that the protein might be important to serotonin's function. Two platelet-specific proteins, platelet factor 4 (PF4) and ß-thromboglobulin ( ßTG) were found to bind serotonin in vitro. Endogenous PF4 was isolated by serotonin-affinity chromatography and was identified by radioimmunoassay. Purified l¹²⁵ I] -PF4 and native PF4 bound to and eluted from a serotonin-affinity column similarly. Ultrafiltration of the homologous protein, (ßTG, with [¹⁴C]-serotonin demonstrated binding of about 8 moles serotonin per mole tetrameric ßTG with a dissociation con stant of about 4 x 10-8ThesisThesis⁻⁸ M. Equilibrium dialysis of PF4 with radiolabelled serotonin was attempted, but no binding constant values were obtained because serotonin apparently bound to the dialysis membrane. Since EDTA was one of the two agents that eluted PF4 from the serotonin-affinity gel, calcium binding by -PF4 was investigated by equilibrium dialysis. Evidence was obtained for positively cooperative binding of calcium ions by PF4. It is concluded that PF4 and ßTG bind serotonin in vitro, that they may also bind in vivo when platelets undergo release, and that the functions of serotonin, PF4 and ßTG may be mediated in part by serotonin-protein associations. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
- Authors: Heemstra, Valerie Lawrence
- Date: 1984 , 2013-04-10
- Subjects: Serotonin , Serotonin -- Metabolism
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3829 , http://hdl.handle.net/10962/d1007215 , Serotonin , Serotonin -- Metabolism
- Description: Among the substances released from human blood platelets are serotonin and various proteins. It was hypothesized that one of these proteins binds serotonin and that serotonin might be important to the protein's function or that the protein might be important to serotonin's function. Two platelet-specific proteins, platelet factor 4 (PF4) and ß-thromboglobulin ( ßTG) were found to bind serotonin in vitro. Endogenous PF4 was isolated by serotonin-affinity chromatography and was identified by radioimmunoassay. Purified l¹²⁵ I] -PF4 and native PF4 bound to and eluted from a serotonin-affinity column similarly. Ultrafiltration of the homologous protein, (ßTG, with [¹⁴C]-serotonin demonstrated binding of about 8 moles serotonin per mole tetrameric ßTG with a dissociation con stant of about 4 x 10-8ThesisThesis⁻⁸ M. Equilibrium dialysis of PF4 with radiolabelled serotonin was attempted, but no binding constant values were obtained because serotonin apparently bound to the dialysis membrane. Since EDTA was one of the two agents that eluted PF4 from the serotonin-affinity gel, calcium binding by -PF4 was investigated by equilibrium dialysis. Evidence was obtained for positively cooperative binding of calcium ions by PF4. It is concluded that PF4 and ßTG bind serotonin in vitro, that they may also bind in vivo when platelets undergo release, and that the functions of serotonin, PF4 and ßTG may be mediated in part by serotonin-protein associations. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
The geology, mineralogy and chemistry of the Grahamstown clay deposits
- Authors: Smuts, Johann, 1951-
- Date: 1984
- Subjects: Clay minerals -- South Africa -- Grahamstown , Mineralogy -- South Africa -- Grahamstown , Geochemistry -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5080 , http://hdl.handle.net/10962/d1015969
- Description: The Grahamstown clay deposits extend in a broad belt from 26°23 to 26°50 East longitude and from 33°15 to 33°22 South latitude along two distinct geomorphological features, the Grahamstown Peneplane (650 m) and the Coastal Plain (520m). The clay deposits traverse four different lithologies including the Bokkeveld Shale, Witteberg Shale, Dwyka Tillite and Ecca Shale. The two planes invariably have a covering of silcrete which is also present over most of the clay deposits except where erosion has taken place. X-ray fluorescence analysis shows that chemically there is a fairly wide variation between and witnin the deposits. The greatest variation is in the Si0₂/Al₂0₃ ratio which appears to be controlled by the parent lithology and to some extent by the amount of leaching. K²0 shows an increase in concentration with depth and therefore indicates the limits of hydrolysis and leaching and of the clay. X-ray diffraction study shows the Peneplane and Coastal Plain deposits to be quite distinct. The Peneplane deposits consist of kaolinite, illite and quartz and the Coastal Plain deposits of kaolinite, illite, quartz and pyrophyllite. The presence of pyrophyllite is not fully understood as there is no indication of major faulting, metamorphism or pyrophyllite in the parent rock. The pyrophyllite most probably represents a transformation product of kaolinite. The kaolinite from the various deposits shows a considerable variation in crystallinity in both the X-ray diffraction traces and electron photomicrographs. The most poorly crystalline kaolinites are from the Coastal Plain deposits and the difference in crystallinity is most probably due to differences in the degree of hydrolysis and the parent rock material in the case of the tillite. Genetically all of the deposits are residual types generated by hydrolysis and subsequent leaching of micas and feldspars. The principal elements leached are silicon, iron and potassium. The hydrolysis and leaching took place over a long period of time in the flat lying areas of the Peneplane and Coastal Plain. The deposits are exploited economically and the clay is used principally in the tile, pottery and whiteware industries with some usage in the paper, refractory and brickmaking industries. The price commanded by raw kaolin is not very high and as a result the clay industry in Grahamstown is not as viable economically as it could be.
- Full Text:
- Date Issued: 1984
- Authors: Smuts, Johann, 1951-
- Date: 1984
- Subjects: Clay minerals -- South Africa -- Grahamstown , Mineralogy -- South Africa -- Grahamstown , Geochemistry -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5080 , http://hdl.handle.net/10962/d1015969
- Description: The Grahamstown clay deposits extend in a broad belt from 26°23 to 26°50 East longitude and from 33°15 to 33°22 South latitude along two distinct geomorphological features, the Grahamstown Peneplane (650 m) and the Coastal Plain (520m). The clay deposits traverse four different lithologies including the Bokkeveld Shale, Witteberg Shale, Dwyka Tillite and Ecca Shale. The two planes invariably have a covering of silcrete which is also present over most of the clay deposits except where erosion has taken place. X-ray fluorescence analysis shows that chemically there is a fairly wide variation between and witnin the deposits. The greatest variation is in the Si0₂/Al₂0₃ ratio which appears to be controlled by the parent lithology and to some extent by the amount of leaching. K²0 shows an increase in concentration with depth and therefore indicates the limits of hydrolysis and leaching and of the clay. X-ray diffraction study shows the Peneplane and Coastal Plain deposits to be quite distinct. The Peneplane deposits consist of kaolinite, illite and quartz and the Coastal Plain deposits of kaolinite, illite, quartz and pyrophyllite. The presence of pyrophyllite is not fully understood as there is no indication of major faulting, metamorphism or pyrophyllite in the parent rock. The pyrophyllite most probably represents a transformation product of kaolinite. The kaolinite from the various deposits shows a considerable variation in crystallinity in both the X-ray diffraction traces and electron photomicrographs. The most poorly crystalline kaolinites are from the Coastal Plain deposits and the difference in crystallinity is most probably due to differences in the degree of hydrolysis and the parent rock material in the case of the tillite. Genetically all of the deposits are residual types generated by hydrolysis and subsequent leaching of micas and feldspars. The principal elements leached are silicon, iron and potassium. The hydrolysis and leaching took place over a long period of time in the flat lying areas of the Peneplane and Coastal Plain. The deposits are exploited economically and the clay is used principally in the tile, pottery and whiteware industries with some usage in the paper, refractory and brickmaking industries. The price commanded by raw kaolin is not very high and as a result the clay industry in Grahamstown is not as viable economically as it could be.
- Full Text:
- Date Issued: 1984
The hydrogeology and hydrogeochemisty of the aquifers of the Hex River Valley, Cape Province
- Authors: Rosewarne, Peter Nigel
- Date: 1984 , 2013-04-11
- Subjects: Hydrogeology , Aquifers , Water chemistry , Hydrogeology -- South Africa -- Cape Colony
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4863 , http://hdl.handle.net/10962/d1007224 , Hydrogeology , Aquifers , Water chemistry , Hydrogeology -- South Africa -- Cape Colony
- Description: The Hex River Valley is one of the main centres in South Africa for cultivation of table grapes of export quality. The vines require irrigation water, which must be low in dissolved solids. Approximately two thirds of the annual irrigation requirement is obtained from boreholes and the balance from surface water sources. During the early 1960s a deterioration in the quality of the groundwater was noticed, becoming critical in some areas, and borehole yields also declined. The main objectives of this study were therefore to obtain an understanding of the hydrogeological and hydrogeochemical processes operating in the valley to explain the derogation of the groundwater resource and enable optimum utilisation and management of the resource in the future. To achieve these objectives, field work involving exploration drilling, aquifer tests, hydrocensus, long-term monitoring of groundwater levels and surfacewater flows and extensive sampling of the ground and surface waters was carried out. Analysis of these data gave quantitative information on groundwater occurrence, aquifer hydraulic properties, groundwater recharge and storage, chemical characteristics of the ground and surfacewaters and sources of dissolved species. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
- Authors: Rosewarne, Peter Nigel
- Date: 1984 , 2013-04-11
- Subjects: Hydrogeology , Aquifers , Water chemistry , Hydrogeology -- South Africa -- Cape Colony
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4863 , http://hdl.handle.net/10962/d1007224 , Hydrogeology , Aquifers , Water chemistry , Hydrogeology -- South Africa -- Cape Colony
- Description: The Hex River Valley is one of the main centres in South Africa for cultivation of table grapes of export quality. The vines require irrigation water, which must be low in dissolved solids. Approximately two thirds of the annual irrigation requirement is obtained from boreholes and the balance from surface water sources. During the early 1960s a deterioration in the quality of the groundwater was noticed, becoming critical in some areas, and borehole yields also declined. The main objectives of this study were therefore to obtain an understanding of the hydrogeological and hydrogeochemical processes operating in the valley to explain the derogation of the groundwater resource and enable optimum utilisation and management of the resource in the future. To achieve these objectives, field work involving exploration drilling, aquifer tests, hydrocensus, long-term monitoring of groundwater levels and surfacewater flows and extensive sampling of the ground and surface waters was carried out. Analysis of these data gave quantitative information on groundwater occurrence, aquifer hydraulic properties, groundwater recharge and storage, chemical characteristics of the ground and surfacewaters and sources of dissolved species. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
The synthesis and properties of some polymer hydrogels
- Authors: Hird, Bryn
- Date: 1984 , 2013-04-05
- Subjects: Colloids
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4428 , http://hdl.handle.net/10962/d1006975 , Colloids
- Description: The interactions between water molecules and polyelectrolyte species in aqueous solutions are reviewed and are used to infer interactions occuring in swollen crosslinked polyelectrolyte hydrogels. Linear poly(acrylic acid ) and derivatives neutralised to varying degrees with alkali-metal hydroxides are prepared and characterised. Samples of these compounds are crosslinked by 'Y - irradiation to form hydrogels. Hydration studies on linear polymers, crosslinked material and a commercial polyacrylate hydrogel indicate a possible hydration structure and provide some insight into the nature of water-polymer interactions within a sHollen polyacrylate gel. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
- Authors: Hird, Bryn
- Date: 1984 , 2013-04-05
- Subjects: Colloids
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4428 , http://hdl.handle.net/10962/d1006975 , Colloids
- Description: The interactions between water molecules and polyelectrolyte species in aqueous solutions are reviewed and are used to infer interactions occuring in swollen crosslinked polyelectrolyte hydrogels. Linear poly(acrylic acid ) and derivatives neutralised to varying degrees with alkali-metal hydroxides are prepared and characterised. Samples of these compounds are crosslinked by 'Y - irradiation to form hydrogels. Hydration studies on linear polymers, crosslinked material and a commercial polyacrylate hydrogel indicate a possible hydration structure and provide some insight into the nature of water-polymer interactions within a sHollen polyacrylate gel. , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
Topical immunotherapy for Pseudomonas keratitis : use of antilipopolyssacharide plasma
- Authors: Rauch, Andrew Johan
- Date: 1984 , 2013-03-13
- Subjects: Pseudomonas infections , Immunotherapy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3817 , http://hdl.handle.net/10962/d1004910 , Pseudomonas infections , Immunotherapy
- Description: Pseudomonas aeruginosa is an opportunistic pathogen capable of infecting the human cornea. Such infections are difficult to treat, and are often fulminative, in that the infected eye is lost, or severely scarred. The use of alternative therapeutic agents has been necessitated by the frequent failure of conventional antibiotic therapy. Equine hyperimmune antilipopolysaccharide plasma (Anti-LPS) was obtained by the plasmapheresis of suitably immunized horses. The plasma contained 1,O- 1 ,5g/ml of LPS-precipitible IgG antibodies. Topical administration of Anti-LPS as a lavage was shown to be effective against Pseudomonas keratitis in rabbits and guinea pigs. Subsequent use of topical corticosteroids was found to further reduce corneal pathology. The improvement noted in these experimental infections involved all three parameters measured, area of keratitis, depth of lesion, and degree of vascularization. In vitro , Anti-LPS was shown to be rapidly bactericidal for Gram negative bacteria. The plasma can therefore be said to have a dual mechanism of action: antitoxic, and antibacterial. Ocular administration of Anti-LPS, by both the topical and subconjunctival routes, was well tolerated by both rabbits and baboons. In conclusion, Anti-LPS is a potentially useful immunotherapeutic agent with many applications in both veteriary and human medicine, particularly in the treatment of surface infections involving antibiotic-resistant Gram negative bacteria , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
- Authors: Rauch, Andrew Johan
- Date: 1984 , 2013-03-13
- Subjects: Pseudomonas infections , Immunotherapy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3817 , http://hdl.handle.net/10962/d1004910 , Pseudomonas infections , Immunotherapy
- Description: Pseudomonas aeruginosa is an opportunistic pathogen capable of infecting the human cornea. Such infections are difficult to treat, and are often fulminative, in that the infected eye is lost, or severely scarred. The use of alternative therapeutic agents has been necessitated by the frequent failure of conventional antibiotic therapy. Equine hyperimmune antilipopolysaccharide plasma (Anti-LPS) was obtained by the plasmapheresis of suitably immunized horses. The plasma contained 1,O- 1 ,5g/ml of LPS-precipitible IgG antibodies. Topical administration of Anti-LPS as a lavage was shown to be effective against Pseudomonas keratitis in rabbits and guinea pigs. Subsequent use of topical corticosteroids was found to further reduce corneal pathology. The improvement noted in these experimental infections involved all three parameters measured, area of keratitis, depth of lesion, and degree of vascularization. In vitro , Anti-LPS was shown to be rapidly bactericidal for Gram negative bacteria. The plasma can therefore be said to have a dual mechanism of action: antitoxic, and antibacterial. Ocular administration of Anti-LPS, by both the topical and subconjunctival routes, was well tolerated by both rabbits and baboons. In conclusion, Anti-LPS is a potentially useful immunotherapeutic agent with many applications in both veteriary and human medicine, particularly in the treatment of surface infections involving antibiotic-resistant Gram negative bacteria , KMBT_363 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 1984
- «
- ‹
- 1
- ›
- »