Diet of two Antarctic dragonfish (Pisces: Bathydraconidae) from the Indian sector of the Southern Ocean
- Authors: Pakhomov, Evgeny A
- Date: 1998
- Subjects: Antarctica Bathydraconidae
- Language: English
- Type: Article
- Identifier: vital:6943 , http://hdl.handle.net/10962/d1011970 , http://dx.doi.org/10.1017/S095410209800008X
- Description: The diet of Cygnodraco mawsoni Waite 1916 and Gymnodraco acuticeps Boulenger 1902 (Pisces: Bathydraconidae) was studied in the Cooperation and Cosmonaut seas in the depth range 200–400 m during the summer 1988. Stomach content analysis showed that both species are piscivorous predators but with different feeding habits. Cygnodraco mawsoni fed mostly on young notothenioid fish, regularly complementing these with pelagic, Euphausia superba, and benthic crustaceans, such as amphipod gammarids and mysids. In contrast, G. acuticeps relied mostly on mesopelagic fish of the family Myctophidae. Although C. mawsoni and G. acuticeps occupy similar depths in the Cosmonaut Sea, different feeding habits appear to limit the probability of interspecific competition for food.
- Full Text:
- Date Issued: 1998
Ecological and morphological differentiation of the honeybees. Apis mellitera linnaeus (Hymenoptera: Apidae). of West Africa
- Authors: Radloff, Sarah E , Hepburn, H Randall , Fuchs, S
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451832 , vital:75080 , https://hdl.handle.net/10520/AJA10213589_253
- Description: Morphometric characters of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations in the sahelian, dry and wet tropical and equatorial regions of western and eastern Africa (mainly between 0 and 15 N latitude, 18 W and 39""E longitude). Two distinct morphocIusters and azoneof hybridization between them were identified. The bees are identified as Apis mellifera adansonii Latreille and A. m. jemenitica Ruttrter. The former subspecies is distributed in the equatorial and wet tropical regions, the latter in the dry tropical and sahelian eco-climatic zones. The hybrid zone extends into the two tropical and savanna biomes and it is suggested that the stability of the hybridization zone is largely the effect of extensive annual fire in the region.
- Full Text:
- Date Issued: 1998
Press alert on the COSATU recruitment drive campaign
- Authors: COSATU
- Date: Mar 1998
- Subjects: COSATU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/112684 , vital:33638
- Description: Members of the Press are invited to a high profile public launch of the COSATU Autumn Offensive Recruitment campaign that will be held on Monday 23 March 1998 at CNR Old Verneeniging and Jacobs Street, Alrode in Alberton - Gauteng at 12noon. In attendance will be members of the COSATU Executive Committee led by President John Gomomo, the ANC and SACP leadership. An invitation has been extended to comrades Thabo Mbeki and Charles Nqakula to speak at the launch.
- Full Text:
- Date Issued: Mar 1998
Sexual dimorphism and tail-length in widowbirds and bishopbirds (Ploeeidae: Euplectes spp.): a reassessment
- Authors: Craig, Adrian J F K , Villet, Martin H
- Date: 1998
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442306 , vital:73974 , https://doi.org/10.1111/j.1474-919X.1998.tb04551.x
- Description: No evidence for sexual selection in the evolution of tail‐length or wing‐length in widow birds and bishopbirds (genus Euplectes) was found when the methods used by previous authors were applied to a larger set of data. Nuptial tail‐length dimorphism scaled with body size dimorphism except in Euplectes progne, and interpopulation variation in taillength could be explained by genetic drift alone. Wing‐length appears to be under stabilizing selection and scales allometrically with body size, with no relation to tail‐length unless E. progne is included in the analysis.
- Full Text:
- Date Issued: 1998
A description of gametogenesis in the panga Pterogymnus laniarius (Pisces: Sparidae) with comments on changes in maturity patterns over the past two decades
- Authors: Booth, Anthony J , Hecht, Thomas
- Date: 1997
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/446930 , vital:74571 , https://www.ajol.info/index.php/az/article/view/154565
- Description: A description of gametogenesis in the panga Pferogymnus laniarius, a common endemic seabream species inhabiting the Agulhas Bank, South Africa, is presented. After sexual maturity, oogenesis and spermatogenesis continued throughout the year and were found to be similar to these processes in other seabream species and teleosts in general. Analysis of maturity data over the past two decades revealed a significant change in both age and size-at-maturity, a response to fishing pressure.
- Full Text:
- Date Issued: 1997
Apparent range expansion of the redbilled quelea Quelea quelea in the Eastern Cape Province of South Africa
- Authors: Whittington-Jones, C A
- Date: 1997
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448426 , vital:74729 , https://doi.org/10.1080/00306525.1997.9639720
- Description: Distribution records obtained from the South African Bird Atlas Project (SABAP) and from published literature show that the known distribution of Redbilled Quelea in the Eastern Cape has changed dramatically over the last century. Increased search effort following the initiation of SABAP may explain the range expansion, but changes in agricultural practice have probably been a contributing factor.
- Full Text:
- Date Issued: 1997
Ecology and genetics of hybrid zones in the southern African Pycnonotus bulbul species complex
- Authors: Lloyd, Penn , Craig, Adrian J F K , Hulley, Patrick E , Essop, M Faadiel , Bloomer, Paulette , Crowe, Timothy M
- Date: 1997
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447801 , vital:74675 , https://doi.org/10.1080/00306525.1997.9639720
- Description: The closely related Blackeyed Bulbul Pycnonotus barbatus, Cape Bulbul P. capensis and Redeyed Bulbul P. nigricans have parapatric to locally sympatric distributions within southern Africa. Extensive hybridization along narrow transition zones between each of the three species pairs is described in a region of the Eastern Cape province, South Africa. The transition zones coincide with ecotones between different vegetation types, which in turn follow escarpments or mountain ranges. The lack of population density depressions within the hybrid zones, together with the variability of the hybrids, suggests the hybrids are viable. Sharp step clines in various phenotypic characters are described across the P. barbatus/P. nigricans hybrid zone. A mtDNA analysis found evidence of possible introgression between P. barbatus and P. capensis. All eight P. barbatus x P. nigricans hybrids analysed possessed P. barbatus mtDNA, suggesting the existence of either positive assortative mating or strong directional selection, but our data are unable to distinguish which.
- Full Text:
- Date Issued: 1997
FAWU - Response to the White Paper On A Marine Fisheries Policy For South Africa
- Authors: FAWU
- Date: 1997
- Subjects: FAWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/118385 , vital:34625
- Description: This document has been written to inform Deputy President Thabo Mbeki of FAWU’s objections to the above-mentioned White Paper. It also includes FAWU’s recommendations for changing the policy. The fishing industry in South Africa is an Apartheid creation. Like other aspects of our society, it needs to be completely transformed and restructured. Currently, the industry is marked by: Monopolised control of every aspect of the fishing value-chain: from production to processing to marketing to distribution; Highly restricted access to the resource by historically disadvantaged members of our society; and Disempowered communities who originally had unrestricted access to marine resources. The above conditions have been created by a process of systematically violating the human rights of fishers and fishing communities. A new White Paper on Fisheries has the potential to change this in a sustainable economic and environmental way. Unfortunately, the 1997 White Paper on Fisheries does not adequately address the legacy of history. In fact, there are more similarities in this Paper to the 1988 Sea Fisheries Act than there is to any framework of transformation. One such framework was put forward by the Fishing Policy Development Committee (FPDC). However, it seems that key aspects of the FPDC’s recommendations were ignored. This is unacceptable.
- Full Text:
- Date Issued: 1997
National Bi-annual Conference - President's address
- Authors: FAWU
- Date: July 1997
- Subjects: FAWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/119031 , vital:34695
- Description: Comrade, General Secretary : Mandla Gxanyana , the acting Office Bearers Lucky Nsizwana , Thomas Basson and Christopher Plaatjies . Leaders of COSATU , SACP , ANC and the present Ministries , Distinguished Guests fraternal forces in the labour movement. I will start by saying we have come a long way as FAWU and we have survived through thick and thin. This was only because of our political understanding and ideological belief on the interconnection of economic struggles with the broad national question. The national liberation has been in the heart of this organisation from its inception in 1941 in the form of African Food and Food and Canning Workers Union. It is both a pleasure and an honour to share the same platform once again with so many leadership of FAWU from all the provinces of our country . Furthermore one feels especially fortunate to be part of this Bi-annual conference . Two years ago in 1995 , we came together in Bloemfontein for a week long Bi-annual Conference . A programme was produced and adopted by the conference and furthermore a action plan to implement the Programme was discussed by the NEC and also endorsed . If we have to be honest not all the aims and objectives we set for ourselves we have manage to achieve them as expected per the mandate of our last Conference , there are number of reasons for that, the G .S report will deal with some of them . Nevertheless we manage to implement some of the areas e.g. setting the tone for Super Bargaining Council which has to put a process of standardise wages in the Food and Beverage Sector and come up with clear industrial policy on the following areas training and grading , industrial provident fund and other benefits. We have reached this date not without problems internally as leaders of the organisation and as the broad membership . Let us lead this organisation and the masses of workers in theory but also in practice. The prospects of achieving a revolutionary break through in South Africa are greater today than ever before in our history. The 27th of April was just a confirmation of the long standing vision of transforming the country from the ashes of Apartheid monopoly Capitalism to Apartheid free South Africa. We owe the workers of this country an answer, the landless rural masses, students , women and all peace loving people. Because it is through the mobilisation , organisation and unity in action of this large front of forces who made it possible from every corner of our country Apartheid to be unworkable.
- Full Text:
- Date Issued: July 1997
A programme for the Alliance
- Authors: Congress of South African Trade Unions
- Date: 1996-11
- Subjects: Uncatalogued
- Language: English
- Type: text , pamphlet
- Identifier: http://hdl.handle.net/10962/105785 , vital:32568
- Description: BACKGROUND TO THE ALLIANCE From Cosatu’s inception in 1985, the federation developed a close association with the Congress movement. Conditions in the country dictated the need to go beyond bread and butter issues to embrace national and class struggle. This perspective was formally endorsed with Cosatu’s adoption of the Freedom Charter in 1987. The 1987 Congress agreed Cosatu should build alliances with mass-based organisations with a track record of struggle and whose principles did not conflict with those of Cosatu. After the unbanning of the liberation movement, Cosatu’s 1991 Congress resolved that the Federation should join the ANC and SACP in alliance in place of Sactu, thus becoming part of the Tripartite Alliance as we know it today. It was understood that this Alliance , here put any information that you think is important but there is no field for it, if there isnt remove the field
- Full Text:
- Date Issued: 1996-11
An extended version of Linda for Transputer systems
- Authors: Wells, George C , Clayton, Peter G , Chalmer, A G
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430512 , vital:72696 , https://dl.acm.org/doi/abs/10.5555/270088.270117
- Description: This paper discusses the associative matching mechanism used in the Linda coordination language for the retrieval of data. There are a number of problems with this mechanism which are discussed in the light of the requirements of applications using Linda. A number of solutions to these problems have been proposed. These are discussed and compared with a new approach to solving these problems. The benefits and the limitations of the new approach are considered, showing how it provides a considerable improvement in this area.
- Full Text:
- Date Issued: 1996
Comparisons of the vocalizations and social behaviour of southern African Pycnonotus bulbuls
- Authors: Lloyd, Penn , Hulley, Patrick E , Craig, Adrian J F K
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447774 , vital:74673 , https://doi.org/10.1080/00306525.1996.9639696
- Description: Vocalizations and associated behaviour of three Pycnonotus species are described, based on field observations and tape recordings from which sonagrams were produced. These species, which are locally sym-patric and hybridize, have similar vocalizations and displays; differences are most apparent in their contact calls and songs. Quantitative analysis of the songs showed that P. barbatus and P. capensis are easily distinguished, whereas the song characteristics of P. nigricans overlap those of both the other species. Playback experiments with territorial male P. barbatus in an area of allopatry showed similar responses to songs of conspecifics and of P. nigricans, but almost no response to the song of P. capensis.
- Full Text:
- Date Issued: 1996
Role of percutaneous penetration enhancers
- Authors: Walker, Roderick B , Smith, Eric W
- Date: 1996
- Language: English
- Type: text , Article
- Identifier: vital:6446 , http://hdl.handle.net/10962/d1006633
- Description: It is clear that scientists are now only beginning to comprehend the complexity of transdermal drug delivery. Elucidation of the biochemical composition and functioning of the intrinsic diffusional barrier of the stratum corneum has prompted investigation of chemical and physical means of enhancing the percutaneous penetration of poorly absorbed drugs. Chemical enhancers that aid absorption of co-administered moieties are currently believed to improve solubility within the stratum corneum or increase lipid fluidity of the intracellular bilayers. Alternatively,the use of ionto- or phonophoresis may facilitate the absorption of some drug molecules by physical alteration of the barrier. The role of penetration enhancer inclusion in topical formulations has been well documented and will undoubtedly, in the future, permit the delivery of broader classes of drugs through the stratum corneum.
- Full Text:
- Date Issued: 1996
Suitability of Metriona elatior (Klug)(Coleoptera: Chrysomelidae: Cassidinae) as a biological control agent for Solanum sisymbriifolium Lam.(Solanaceae).
- Authors: Hill, Martin P , Hulley, Patrick E
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451540 , vital:75058 , https://hdl.handle.net/10520/AJA10213589_195
- Description: A leaf-feeding tortoise beetle, Metriona elatior (Klug), was screened as a biological control agent for the weed Solanum sisymbriifolium Lam. in South Africa. Favourable biological characteristics of M. elatior include a high reproductive capacity, long-lived adults and several generations per year under laboratory conditions. Host range was investigated by larval survival, and host plant choice tests by adults. Larvae were successfully reared on 10 of 11native Solanum species tested, five exotic Solanum species (except S. sisymbriifolium) and on the economically important eggplant, S. melongena L. The adult females selected these native and exotic Solanum species, and eggplant as suitable for oviposition. Based on these results it was decided not to apply for release of this insect.
- Full Text:
- Date Issued: 1996
AIA's Southern Africa Chronicle - Volume VIII No.3
- Authors: Africa Information Afrique (AIA)
- Date: 1995
- Subjects: AIA
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/169401 , vital:41746
- Description: Machipanda, February 3,1995 (AIA/Brian Latham)—Many Zimbabwean peasants have quietly found the solution to land shortages by crossing into neighbouring Mozambique where it is plentiful. For as little as US$ 10 a field, they are acquiring land and a place to live — probably illegally — from chiefs and headmen across the border. Information on how to get land is easily accessible in Machipanda, the Mozambique border town at the head of the Beira Corridor from Zimbabwe to the Indian Ocean. Confusion reigns in Mozambique in the aftermath of the devastating civil war. And in a country reputed to be the poorest on earth, the government can do little to control the flood of border jumpers in both directions: Mozambicans enter Zimbabwe to sell everything from guns to clothes donated by aid agencies and Zimbabweans enter Mozambique in search of land to till.
- Full Text:
- Date Issued: 1995
Building a firm base for policy consensus statement
- Authors: NEDLAC
- Date: 1995
- Subjects: NEDLAC
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/151641 , vital:39156
- Description: We have arrived at a very important stage in the development of our country - one that will be most testing and challenging for all of us. Our second revolution, so to speak, is only beginning. The Government of National Unity, has come a long way in addressing the key political questions. Advancement from here lies in our economic prerogative. We are all concerned with the major economic challenge that lies ahead. Sustainable economic growth, the creation of wealth and equity, the provision of jobs and basic needs underpin the need to provide mechanisms which will facilitate growth, development and delivery. But our concern is not limited to our domestic economy.
- Full Text:
- Date Issued: 1995
An evaluation of different methods of preparation of quartz grains for study of their surface features by scanning electron microscopy
- Authors: Lewis, Colin A , Armstrong, Glynis A S
- Date: 1994
- Language: English
- Type: Article
- Identifier: vital:6705 , http://hdl.handle.net/10962/d1006741
- Description: Sediments from periglacial and glacial environments were subjected to initial preparation and portions were subsequently further prepared using either the dichromate or the hydrogen peroxide method before being examined by scanning electron microscopy. Statistically significant differences did not occur in the results obtained for samples subjected only to initial or to initial and either of the two further preparations: it is concluded that initial preparation is satisfactory and further preparation unnecessary.
- Full Text:
- Date Issued: 1994
Promotion of the Etendeka Formation to Group status: a new integrated stratigraphy
- Authors: Milner, Simon C , Duncan, Andrew R , Ewart, A , Marsh, Julian S
- Date: 1994
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145482 , vital:38442
- Description: The Etendeka volcanic rocks of northwestem Namibia are currently defined as the upper part of the Karoo Sequence in Namibia and have thus been represented as stratigraphically equivalent to the volcanic rocks of the Karoo Sequence in South Africa, Botswana, Lesotho, Swaziland and Zimbabwe. However, the Etendeka volcanic rocks (130-135 Ma) are considerably younger than those of the Karoo Sequence (180-190 Ma) in the areas mentioned above. They are compositionally distinct from Karoo volcanic rocks, and constitute an eastern portion of the Parana Igneous Province of Brazil. Stratigraphic studies have shown the Etendeka Formation to be made up of several definable volcanic successions and it is suggested that these successions now be formally recognized as Formations within an Etendeka Group which itself should no longer be part of the Karoo Sequence. Prominent quartz latite units and sequences of basalt flows are defined as Members within the new Formations.
- Full Text:
- Date Issued: 1994
The ultrastructure and computer-enhanced digital image analysis of plasmodesmata at the Kranz mesophyll-bundle sheath interface of Themeda triandra var. imberbis (Retz) A. Camus in conventionally-fixed leaf blades
- Authors: Botha, Christiaan E J , Hartley, B J , Cross, Robin H M
- Date: 1993
- Language: English
- Type: Article
- Identifier: vital:6502 , http://hdl.handle.net/10962/d1005925
- Description: The ultrastructure of the plasmodesmata at the Kranz mesophyll-bundle sheath (KMS-BS) interface in Themeda triandra, and the substructures within the plasmodesmata were investigated, using conventionally fixed leaf-blade material, enhanced by the addition of 0.1% tannic acid to the primary fixative. Examination of high-resolution electronmicrographs, and computer-enhanced digital images suggests that these plasmodesmata are complex structures, comprised of helically-arranged particulate material. The electron-dense particles are between 2.5 and 3.0nm in diameter. These particles are specifically associated with the inner face of the inner plasmalemma membrane leaflet, and the outer region of the desmotubule wall. The electron-dense particles are presumably proteinaceous and embedded in a lipid matrix. In the constricted median portion of the KMS-BS plasmodesmata, the space between the desmotubule and the inner plasmalemma membrane leaflet and areas surrounding the proteinaceous particles thereof (the cytoplasmic sleeve) is about 3nm in cross-section, and constitutes what we believe to be the space through which intercellular transport takes place.
- Full Text: false
- Date Issued: 1993