Towards revised physically based parameter estimation methods for the Pitman monthly rainfall-runoff model
- Kapangaziwiri, Evison, Hughes, Denis A
- Authors: Kapangaziwiri, Evison , Hughes, Denis A
- Date: 2008
- Language: English
- Type: text , Article
- Identifier: vital:7088 , http://hdl.handle.net/10962/d1012417
- Description: This paper presents a preliminary stage in the development of an alternative parameterisation procedure for the Pitman monthly rainfall runoff model which enjoys popular use in water resource assessment in Southern Africa. The estimation procedures are based on the premise that it is possible to use physical basin properties directly in the quantification of the soil moisture accounting, runoff, and recharge and infiltration parameters. The results for selected basins show that the revised parameters are at least as good as current regionalised sets or give satisfactory results in areas where no regionalised parameters exist.
- Full Text:
- Date Issued: 2008
- Authors: Kapangaziwiri, Evison , Hughes, Denis A
- Date: 2008
- Language: English
- Type: text , Article
- Identifier: vital:7088 , http://hdl.handle.net/10962/d1012417
- Description: This paper presents a preliminary stage in the development of an alternative parameterisation procedure for the Pitman monthly rainfall runoff model which enjoys popular use in water resource assessment in Southern Africa. The estimation procedures are based on the premise that it is possible to use physical basin properties directly in the quantification of the soil moisture accounting, runoff, and recharge and infiltration parameters. The results for selected basins show that the revised parameters are at least as good as current regionalised sets or give satisfactory results in areas where no regionalised parameters exist.
- Full Text:
- Date Issued: 2008
The synthesis and electrochemical behaviour of water soluble manganese phthalocyanines: Anion radical versus Mn(I) species
- Sehlotho, Nthapo, Durmuş, M, Ahsen, N, Nyokong, Tebello
- Authors: Sehlotho, Nthapo , Durmuş, M , Ahsen, N , Nyokong, Tebello
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6596 , http://hdl.handle.net/10962/d1004345
- Description: The following MnPc derivatives were synthesized: 1,(4)-tetra-(2-mercaptopyridine) phthalocyaninato manganese(III)(OH) (5a), quaternized 1,(4)-tetra-(2-mercaptopyridine) phthalocyaninato manganese(III)(OH) (5b), 2,(3)-tetra-(2-mercaptopyridine) phthalocyaninato manganese(III)(OH) (6a) and quaternized 2,(3)-tetra-(2-mercaptopyridine) phthalocyaninato manganese(III)(OH)(6b). Spectro-electrochemistry shows that the reduction of Mn(II)Pc to Mn(I)Pc occurs only when the complexes are in their quaternized form (5b and 6b). The reduction (to Mn(I)Pc(−2)) of the quaternized form occurs at a lower potential than that (to Mn(II)Pc(−3)) of the unquaternized form. This observation suggests that metal reduction (to Mn(I)Pc(−2)) versus ligand reduction (to Mn(II)Pc(−3)) in Mn(II)Pc complexes depends on the nature of the ring substituents.
- Full Text:
- Date Issued: 2008
- Authors: Sehlotho, Nthapo , Durmuş, M , Ahsen, N , Nyokong, Tebello
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6596 , http://hdl.handle.net/10962/d1004345
- Description: The following MnPc derivatives were synthesized: 1,(4)-tetra-(2-mercaptopyridine) phthalocyaninato manganese(III)(OH) (5a), quaternized 1,(4)-tetra-(2-mercaptopyridine) phthalocyaninato manganese(III)(OH) (5b), 2,(3)-tetra-(2-mercaptopyridine) phthalocyaninato manganese(III)(OH) (6a) and quaternized 2,(3)-tetra-(2-mercaptopyridine) phthalocyaninato manganese(III)(OH)(6b). Spectro-electrochemistry shows that the reduction of Mn(II)Pc to Mn(I)Pc occurs only when the complexes are in their quaternized form (5b and 6b). The reduction (to Mn(I)Pc(−2)) of the quaternized form occurs at a lower potential than that (to Mn(II)Pc(−3)) of the unquaternized form. This observation suggests that metal reduction (to Mn(I)Pc(−2)) versus ligand reduction (to Mn(II)Pc(−3)) in Mn(II)Pc complexes depends on the nature of the ring substituents.
- Full Text:
- Date Issued: 2008
Retrospective stock assessment of the Emperor red snapper (Lutjanus sebae) on the Seychelles Bank between 1977 and 2006
- Grandcourt, E M, Hecht, Thomas, Booth, Anthony J, Robinson, J
- Authors: Grandcourt, E M , Hecht, Thomas , Booth, Anthony J , Robinson, J
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125887 , vital:35829 , https://doi.10.1093/icesjms/fsn064
- Description: The Emperor red snapper, Lutjanus sebae, known as “Bourzwa” in the Seychelles, is distributed throughout the Indo-West Pacific from the southern Red Sea and East Africa to New Caledonia, north to Japan and south to Australia. It occurs near coral or rocky reefs and also over adjacent sand flats and gravel patches between 5 and 180 m deep (Allen, 1985; Anderson, 1986). Juveniles are frequently commensal with sea urchins (Kuiter and Tonozuka, 2001), and are found in nearshore, turbid waters (Williams and Russ, 1992), mangrove areas (Allen, 1985), and around coastal and offshore reefs (Williams and Russ, 1992). Larger L. sebae are generally found deeper, although they are also known to move into shallower water during winter (McPherson et al., 1988; Williams and Russ, 1992). Prey items include fish, crabs, other benthic crustaceans, and cephalopods. Lutjanus sebae is a large, long-lived species, attaining a maximum size of 116 cm fork length (McPherson and Squire, 1992) and maximum age of 34 years (Newman and Dunk, 2002). Despite an absence of data on its population structure, mixing, and identity, the population on the Seychelles Bank has been considered to be a unit stock for assessment purposes because of its remote location (e.g. Lablache and Carrara, 1988; Mees, 1992).
- Full Text:
- Date Issued: 2008
- Authors: Grandcourt, E M , Hecht, Thomas , Booth, Anthony J , Robinson, J
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125887 , vital:35829 , https://doi.10.1093/icesjms/fsn064
- Description: The Emperor red snapper, Lutjanus sebae, known as “Bourzwa” in the Seychelles, is distributed throughout the Indo-West Pacific from the southern Red Sea and East Africa to New Caledonia, north to Japan and south to Australia. It occurs near coral or rocky reefs and also over adjacent sand flats and gravel patches between 5 and 180 m deep (Allen, 1985; Anderson, 1986). Juveniles are frequently commensal with sea urchins (Kuiter and Tonozuka, 2001), and are found in nearshore, turbid waters (Williams and Russ, 1992), mangrove areas (Allen, 1985), and around coastal and offshore reefs (Williams and Russ, 1992). Larger L. sebae are generally found deeper, although they are also known to move into shallower water during winter (McPherson et al., 1988; Williams and Russ, 1992). Prey items include fish, crabs, other benthic crustaceans, and cephalopods. Lutjanus sebae is a large, long-lived species, attaining a maximum size of 116 cm fork length (McPherson and Squire, 1992) and maximum age of 34 years (Newman and Dunk, 2002). Despite an absence of data on its population structure, mixing, and identity, the population on the Seychelles Bank has been considered to be a unit stock for assessment purposes because of its remote location (e.g. Lablache and Carrara, 1988; Mees, 1992).
- Full Text:
- Date Issued: 2008
Development and validation of the Xhosa translations of the Beck Inventories: 1. Challenges of the translation process
- Steele, Gary I, Edwards, David J A
- Authors: Steele, Gary I , Edwards, David J A
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6248 , http://hdl.handle.net/10962/d1007866
- Description: This article describes the translation of the Beck Depression Inventory-II, the Beck Hopeless Scale, and the Beck Anxiety Inventory, into Xhosa the language spoken in the Eastern Cape of South Africa. The processes of translation, back-translation and committee discussion failed to yield trustworthy translations because of practical difficulties in working with translators. Critical words and phrases were identified which gave rise to lack of agreement. For each, a range of options was generated and the advantages and disadvantages evaluated in terms of criteria such as conceptual and idiomatic equivalence, and extensiveness of usage. Examples are given of the problems encountered and the way in which final decisions were made. A pilot clinical trial demonstrated the acceptability of the translated Instruments. Two further articles report the psychometric evaluation of the translated scales.
- Full Text:
- Date Issued: 2008
- Authors: Steele, Gary I , Edwards, David J A
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6248 , http://hdl.handle.net/10962/d1007866
- Description: This article describes the translation of the Beck Depression Inventory-II, the Beck Hopeless Scale, and the Beck Anxiety Inventory, into Xhosa the language spoken in the Eastern Cape of South Africa. The processes of translation, back-translation and committee discussion failed to yield trustworthy translations because of practical difficulties in working with translators. Critical words and phrases were identified which gave rise to lack of agreement. For each, a range of options was generated and the advantages and disadvantages evaluated in terms of criteria such as conceptual and idiomatic equivalence, and extensiveness of usage. Examples are given of the problems encountered and the way in which final decisions were made. A pilot clinical trial demonstrated the acceptability of the translated Instruments. Two further articles report the psychometric evaluation of the translated scales.
- Full Text:
- Date Issued: 2008
Coming to terms with the "Border War" in post-apartheid South Africa
- Authors: Baines, Gary F
- Date: 2008
- Language: English
- Type: Conference paper
- Identifier: vital:6157 , http://hdl.handle.net/10962/d1007077
- Description: If you are a white, male South African between the ages of about 35 and 60 it is very likely that you donned the nutria brown uniform of the South African Defence Force (SADF). Between 1967 and 1994 approximately 300 000 young white males were conscripted by the SADF. As far as most of these conscripts were concerned, there was no option other than heeding the call-up and performing national service or diensplig. Failure to do so meant harsh penalties. The alternatives were to object on conscientious (actually religious) grounds and face a six year jail sentence, or flee the country. And the obligation did not end with national service as conscripts were assigned to citizen force or commando units that were liable for periodical call-ups for camps that might have included deployment in the “operational areas” from 1974 or tours of duty in the black townships from 1984. Those - like myself - belonging to this national service generation were part-time soldiers for much of their adult lives. Most served willingly, some with patriotic fervour. Others did so reluctantly and with little enthusiasm.
- Full Text:
- Date Issued: 2008
- Authors: Baines, Gary F
- Date: 2008
- Language: English
- Type: Conference paper
- Identifier: vital:6157 , http://hdl.handle.net/10962/d1007077
- Description: If you are a white, male South African between the ages of about 35 and 60 it is very likely that you donned the nutria brown uniform of the South African Defence Force (SADF). Between 1967 and 1994 approximately 300 000 young white males were conscripted by the SADF. As far as most of these conscripts were concerned, there was no option other than heeding the call-up and performing national service or diensplig. Failure to do so meant harsh penalties. The alternatives were to object on conscientious (actually religious) grounds and face a six year jail sentence, or flee the country. And the obligation did not end with national service as conscripts were assigned to citizen force or commando units that were liable for periodical call-ups for camps that might have included deployment in the “operational areas” from 1974 or tours of duty in the black townships from 1984. Those - like myself - belonging to this national service generation were part-time soldiers for much of their adult lives. Most served willingly, some with patriotic fervour. Others did so reluctantly and with little enthusiasm.
- Full Text:
- Date Issued: 2008
Household attributes promote diversity of tree holdings in rural areas, South Africa:
- Shackleton, Charlie M, Paumgarten, Fiona, Cocks, Michelle L
- Authors: Shackleton, Charlie M , Paumgarten, Fiona , Cocks, Michelle L
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141301 , vital:37960 , DOI: 10.1007/s10457-007-9066-5
- Description: Trees within the homestead area provide many functions to rural households. However, within the semi-arid regions of southern Africa, there has been only limited examination of the correlates between the socio-economic attributes of rural households and the density, species richness and types of trees they keep. This paper reports on a multivariate analysis of household attributes in relation to homestead tree holdings from six rural villages in South Africa. In terms of density of trees per household, gender of the household head was the only significant correlate, with female-headed households having significantly fewer trees than their male-headed counterparts. This was especially so for the density of indigenous trees.
- Full Text:
- Date Issued: 2008
- Authors: Shackleton, Charlie M , Paumgarten, Fiona , Cocks, Michelle L
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141301 , vital:37960 , DOI: 10.1007/s10457-007-9066-5
- Description: Trees within the homestead area provide many functions to rural households. However, within the semi-arid regions of southern Africa, there has been only limited examination of the correlates between the socio-economic attributes of rural households and the density, species richness and types of trees they keep. This paper reports on a multivariate analysis of household attributes in relation to homestead tree holdings from six rural villages in South Africa. In terms of density of trees per household, gender of the household head was the only significant correlate, with female-headed households having significantly fewer trees than their male-headed counterparts. This was especially so for the density of indigenous trees.
- Full Text:
- Date Issued: 2008
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