List of Titles

Evaluating and improving morpho-syntactic classification over multiple corpora using pre-trained, off-the-shelf, parts-of-speech tagging tools reviewed article

- Glass, Kevin R, Bangay, Shaun D

Authors: Glass, Kevin R , Bangay, Shaun D
Date: 2008
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/433427 , vital:72969 , https://hdl.handle.net/10520/EJC28053
Description: This paper evaluates six commonly available parts-of-speech tagging tools over corpora other than those upon which they were originally trained. In particular this investigation measures the performance of the selected tools over varying styles and genres of text without retraining, under the assumption that domain specific training data is not always available. An investigation is performed to determine whether improved results can be achieved by combining the set of tagging tools into ensembles that use voting schemes to determine the best tag for each word. It is found that while accuracy drops due to non-domain specific training, and tag-mapping between corpora, accuracy remains very high, with the support vector machine-based tagger, and the decision tree-based tagger performing best over different corpora. It is also found that an ensemble containing a support vector machine-based tagger, a probabilistic tagger, a decision-tree based tagger and a rule-based tagger produces the largest increase in accuracy and the largest reduction in error across different corpora, using the Precision-Recall voting scheme.
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Juvenile population dynamics of Oreochromis mossambicus in an intermittently open estuary at the limit of its natural distribution

- Ellender, Bruce R, Weyl, Olaf L F, Shanyengange, M K, Cowley, Paul D

Authors: Ellender, Bruce R , Weyl, Olaf L F , Shanyengange, M K , Cowley, Paul D
Date: 2008
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/446893 , vital:74568 , https://doi.org/10.1080/15627020.2008.11657245
Description: Juvenile Oreochromis mossambicus in the 25 ha, temperate, intermittently open, East Kleinemonde Estuary in the Eastern Cape, South Africa (33°32’S, 27°03’E), showed a seasonal shift in distribution, occupying all areas of the estuary in summer and, subsequently, being limited to the upper reaches in winter. The young of the year in the littoral zone were rapidly depleted and resultant estimates of the instantaneous rate of total mortality (Z) ranged from 5.4/yr to 6.9/yr. High annual rates of juvenile mortality and small adult populations imply that stock recovery after a reduction in adult population numbers, through activities such as fishing, may be slow. This work adds to the knowledge base of O. mossambicus ecology and population dynamics in temperate estuaries at the limit of its natural distribution.
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Marine reservoir corrections : St. Helena, South Atlantic Ocean

- Lewis, Colin A, Reimer, P J, Reimer, R W

Authors: Lewis, Colin A , Reimer, P J , Reimer, R W
Date: 2008
Language: English
Type: Article
Identifier: vital:6701 , http://hdl.handle.net/10962/d1006737
Description: We present the first marine reservoir age and ∆R determination for the island of St. Helena using marine mollusk radiocarbon dates obtained from an historical context of known age. This represents the first marine reservoir age and ∆R determination in the southern Atlantic Ocean within thousands of kilometers of the island. The depletion of 14C in the shells indicates a rather larger reservoir age for that portion of the surface Atlantic than models indicate. The implication is that upwelling old water along the Namibian coast is transported for a considerable distance, although it is likely to be variable on a decadal timescale. An artilleryman’s button, together with other artifacts found in a midden, demonstrate association of the mollusk shells with a narrow historic period of AD 1815–1835.
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The localisation into isiXhosa of the iLanga telephone system

- Dalvit, Lorenzo, Tsietsi, Mosiuoa, Terzoli, Alfredo, Maseko, Pamela, Sam, Msindisi S, Mapi, Thandeka

Authors: Dalvit, Lorenzo , Tsietsi, Mosiuoa , Terzoli, Alfredo , Maseko, Pamela , Sam, Msindisi S , Mapi, Thandeka
Date: 2008
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/431358 , vital:72767 , https://nru.uncst.go.ug/bitstream/handle/123456789/6552/Information Communica-tion Technologies page 410.pdf?sequence=1isAllowed=y#page=256
Description: In this paper we describe the localisation of iLanga, a VoIP PBX sys-tem, into isiXhosa. In South Africa, for social and political reasons, mak-ing systems available in the African languages is becoming more and more important. On the one hand, it gives access to the use of technol-ogy to people who are not fluent in English. On the other hand, it has a strong symbolic value. Although a variety of software is already availa-ble in a number of African languages, localisation in such language is still in its early stage. The process presented interesting challenges both from the technical and the linguistic point of view.
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The role of indigenous knowledge in computer education in Africa

- Dalvit, Lorenzo, Murray, Sarah R, Terzoli, Alfredo

Authors: Dalvit, Lorenzo , Murray, Sarah R , Terzoli, Alfredo
Date: 2008
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/431033 , vital:72739 , https://doi.org/10.1007/978-0-387-09729-9_43
Description: The integration of indigenous knowledge/languages in formal education is a contentious issue in post-colonial Africa. For historical and econom-ic reasons, these are devalued in the formal education system. We ar-gue that appropriate use of indigenous knowledge/languages can em-power African students academically even in typically “Western” disci-plines, such as Computer Science. We discuss the potential role of in-digenous languages/knowledge in ICT education and then describe an intervention, supporting students from marginalised communities, at a South African University.
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Transitions towards a knowledge society: Aspectual pre-evaluation of a culture-sensitive implementation framework

- Thinyane, Mamello, Terzoli, Alfredo, Clayton, Peter G

Authors: Thinyane, Mamello , Terzoli, Alfredo , Clayton, Peter G
Date: 2008
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/431054 , vital:72741 , https://doi.org/10.1007/978-0-387-09729-9_41
Description: Information and Communication Technology (ICT) is aiding the transi-tion of society into information society and ultimately knowledge society. Embedded within ICT are the cultural and philosophical undercurrents of the society in which the ICT solutions are developed, currently pre-dominantly the Western culture. The proliferation of ICT is therefore in-advertedly leading to more Westernization of the world. It is important, therefore, that ICT solutions are culture sensitive and flexible enough to be situated within different cultures. To that end, we utilize Herman Dooyeweerd’s Theory of Modal Aspects to analyze a framework we has developed for implementation of locally situated knowledge based systems, to determine its efficacy in addressing the different modal as-pects, which make up the total experience and cultural expressiveness of societies.
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Karyology of three evolutionarily hexaploid southern African species of yellowfish, Labeobarbus Rüppel, 1836 (Cyprinidae)

- Naran, Daksha, Skelton, Paul H, Villet, Martin H

Authors: Naran, Daksha , Skelton, Paul H , Villet, Martin H
Date: 2007
Language: English
Type: Article
Identifier: vital:6855 , http://hdl.handle.net/10962/d1011138 , http://dx.doi.org/10.3377/1562-7020(2007)42[254:KOTEHS]2.0.CO;2
Description: The karyotypes of three species of yellowfish, namely Labeobarbus marequensis (A. Smith, 1841), L. capensis (A. Smith, 1841) and L. polylepis (Boulenger, 1907), were examined by Giemsa staining using an approach improved for the description of high chromosome numbers. In each case, 2n = 150; no heteromorphic chromosomes were detected; chromosomes in all morphological categories ranged smoothly from large to small, with no distinctly large submetacentric pairs; and metacentric chromosomes showed little variation in size. Labeobarbus marequensis had 26 metacentric (m), 44 submetacentric (sm), 42 subtelocentric (st) and 38 acrocentric (a) chromosomes and a fundamental number (FN) of 262; L. capensis had 16 m, 58 sm, 42 st and 34 a chromosomes and FN = 266; and L. polylepis had 18 m, 60 sm, 42 st and 30 a chromosomes and FN = 270. These results, combined with published literature, imply that Labeobarbus Rüppel, 1836 is an evolutionarily hexaploid African lineage and support its removal from synonymy with the evolutionarily tetraploid Asian genus Tor Gray, 1834. A review of fundamental numbers for conspecific Labeobarbus species examined in different studies implicated karyological technique as a confounding factor in assessing details of karyotypes, leading to recommendations for future karyological studies of barbine fishes. Potential synapomorphies are pointed out in karyological characters of species within Labeobarbus.
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Nesting success and survival rates of suburban Olive Thrushes (Turdus olivaceus olivaceus).

- Bonnevie, Bo T

Authors: Bonnevie, Bo T
Date: 2007
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/448299 , vital:74720 , https://doi.org/10.2989/OSTRICH.2007.78.2.19.99
Description: Adult survival rates of suburban Olive Thrushes (Turdus olivaceus) were estimated from the proportion of adults and juveniles in mist-net samples from the Eastern Cape and Western Cape provinces of South Africa. These survival rates were compared to an estimate from recovery data. Reproductive rate, clutch size, nesting success and survival rate of dependent fledglings were estimated from breeding records in the Eastern Cape. These data were used to estimate survival rate of independent fledglings. The estimated adult survival rate in this region was high and the clutch size was small, compared to those of the Blackbird (Turdus merula) in Europe. Dispersal patterns from recapture and recovery data, and the relatively low survival rates of juvenile birds, suggest that fledglings are most vulnerable when they reach independence and leave their natal territories.
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The status of the southern ground-hornbill in the Grahamstown region, Eastern Cape, South Africa

- Hulley, Patrick E, Craig, Adrian J F K

Authors: Hulley, Patrick E , Craig, Adrian J F K
Date: 2007
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/447909 , vital:74683 , https://www.tandfonline.com/doi/pdf/10.2989/OSTRICH.2007.78.1.13.57
Description: The Eastern Cape has been the southernmost limit of distribution for the Southern Ground-Hornbill Bucorvus leadbeateri throughout the period for which there are written records (Vernon 1986, Vernon and Herremans 1997). No records are known west of Port Elizabeth and the only ones from this 1 map square (33 S 27 E) date from the nineteenth century. Vernon (1986) noted that nest and roost sites for groundhornbills were in large trees or on cliffs, from which the birds commuted to forage in open country. The forest/thicket and grassland mosaic in the Eastern Cape is apparently ancient (Skead 1987), but the grassland sector has been greatly modified by agriculture and human settlement. Since the assessment of the Southern Ground-Hornbill’s status as ‘vulnerable’in the latest Red Data Book (Barnes 2000), it has been suggested that populations in South Africa have declined to a point where its true status is ‘endangered’but this revision was not accepted by IUCN (AC Kemp, pers. comm.). The recent initiative by the Mabula-based NGO, the Ground-hornbill Research and Conservation Project, to reintroduce birds to the Eastern Cape, prompted us to examine records of sightings in this region. The main focus is the Grahamstown map square 33 S 26 E, in which the release site of the first birds—Shamwari Private Game Reserve—is situated. Our source is the published records in Diaz Diary, the newsletter of the Diaz Cross Bird Club, which has branches in Grahamstown and Kenton-on-Sea, covering the period 1978–2004 inclusive.
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A history of southern African research relevant to forensic entomology

- Williams, Kirstin A, Villet, Martin H

Authors: Williams, Kirstin A , Villet, Martin H
Date: 2006
Language: English
Type: text , Article
Identifier: vital:6909 , http://hdl.handle.net/10962/d1011862
Description: Entomological forensic evidence has been used in southern Africa for decades but explicitly forensic research began in southern Africa only 26 years ago. Although applicable local research has accumulated since 1921, it is scattered in a diverse literature or unpublished. Some overseas research has also touched on local species. This review uses a historical approach to synthesize the southern African literature and to illustrate the cross-disciplinary, opportunistic nature of forensic entomology. Distinct phases of research focused on agriculture (1921-1950), medicine (1952- 1965), ecology (1968-1990) and forensics (1980-2005), but systematics spanned the entire period and tended to be ad hoc. Few scientists were involved, situated at geographically distant locations and with widely disparate research interests. The review concludes with an overview of southern African entomologists who have been involved in medico-legal investigations, and a critical evaluation of the past and future of the discipline locally.
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African Coelacanth Ecosystem Programme: An overview of the conference contributions

- Ribbink, Anthony J, Roberts, Michael J

Authors: Ribbink, Anthony J , Roberts, Michael J
Date: 2006
Language: English
Type: text , Article
Identifier: vital:7127 , http://hdl.handle.net/10962/d1010637
Description: Latimeria chalumnae is the icon for the multidisciplinary, multinational African Coelacanth Ecosystem Programme (ACEP) dedicated to improving the understanding of biological and other processes that support marine life. This article provides an overview of contributions made at a conference hosted by ACEP at the end of 2003. It also reviews significant developments regarding coelacanth conservation which have taken place since the conference. Delegates at the meeting concluded that the integrated regional,ecosystem approach that had been adopted by ACEP should continue. Underwater observation and exploration, however, should be supplemented by more experimental and technical analyses in order to answer longstanding questions related to coelacanths and other organisms.
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Exploitation status of infralittoral abalone (Haliotis midae) and alikreukel (Turbo sarmaticus) in the southern section of the Eastern Cape coast, South Africa

- Proudfoot, Lee-Anne, Kaehler, Sven, McGarry, Dylan K, Uppink, P A, Aereboe, Michael, Morris, K M

Authors: Proudfoot, Lee-Anne , Kaehler, Sven , McGarry, Dylan K , Uppink, P A , Aereboe, Michael , Morris, K M
Date: 2006
Language: English
Type: Article
Identifier: vital:6915 , http://hdl.handle.net/10962/d1011878
Description: Intertidal size-frequency distributions and densities for Haliotis midae and Turbo sarmaticus were examined at 10 sites experiencing varying pressure of human exploitation along the southern section of the Eastern Cape coast, South Africa. Target species' densities and maximum sizes were related both to the numbers of collectors on the shore and to indirect indicators of exploitation such as number of households in the vicinity and distance to the nearest beach access point. For both species, there was variation in density (P < 0.05) and size (P < 0.05) among sites, with densities ranging between 0.03-2.23 m^(-2) and 0.07-4.93 m^(-2) for H. midae and T. sarmaticus, respectively. Maximum sizes ranged between 49.4-153.5 mm (H. midae) and 28.3-104.4 mm (T. sarmaticus) shell length. Population parameters such as mean maximum size and total density were significantly negatively related to exploitation indicators for both species. In addition, densities of sexually mature and legal-size individuals of T. sarmaticus were significantly negatively related to the number of households. However, only for H. midae were densities of subadults significantly negatively related to the number of collectors, suggesting that reproduction of abalone may be suppressed at the most exploited sites. Exploitation of T. sarmaticus tends to be localized near population centres, whereas H. midae is collected over a larger range of sites. Overall, T. sarmaticus is less affected by exploitation than H. midae.
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Floral resources of Apis mellifera capensis in the fynbos biome in the Eastern Cape Province, South Africa

- Addi, A, Phillipson, P, Hepburn, H Randall

Authors: Addi, A , Phillipson, P , Hepburn, H Randall
Date: 2006
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/451845 , vital:75081 , https://hdl.handle.net/10520/EJC32660
Description: The plant species utilized by Cape honeybees, Apis mellifera capensis, as primary nectar and pollen sources were studied in the Eastern Cape Province in an area where fynbos vegetation mingles with grassland communities. From direct field observations and analyses of pollen loads collected by foragers, 54 plant species were identified as nectar and pollen sources. Of 37 endemic and exotic pollen source plants, Metalasia muricata, Eucalyptus grandis, E. camadulensis, Erica chamissonis, Helichrysum odoratissimum, H. anomalum, Crassula cultrata and Acacia longifolia were dominant species.
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The relationship between human exploitation pressure and condition of mussel populations along the south coast of South Africa

- Rius, Marc, Kaehler, Sven, McQuaid, Christopher D

Authors: Rius, Marc , Kaehler, Sven , McQuaid, Christopher D
Date: 2006
Language: English
Type: Article
Identifier: vital:6913 , http://hdl.handle.net/10962/d1011876
Description: Human exploitation of intertidal organisms in South Africa is an ancient activity based principally on mussels. We studied mussel populations and patterns of exploitation along a 160-km stretch of the south coast. Photographs (100 per site) were taken of the intertidal rocks at each of 14 sites, covering a range of exploitation intensities. Percentage cover was negatively correlated with number of mussel patches and positively correlated with mean shell width. PCA analysis identified groups of sites: a) accessible and unprotected sites: low cover, small mussels, patchy distribution; b) inaccessible sites and sites next to, or within, nature reserves: high percentage cover, large animals, less patchy distributions. Affluent coastal settlements also seem to confer protection against harvesting. Harvester distribution was examined by aerial surveys and combined with information on distance to the nearest beach access point and number of households within 7 km for each site. Sites within reserves and inaccessible sites had low densities of collectors, whereas sites near urban areas and in the Ciskei had the highest densities. All correlations between indicators of human exploitation and condition of mussel populations were non-significant. However, number of collectors showed positive trends with number of patches and negative trends for the two other variables. The results indicate much lower levels of exploitation than in the neighouring Transkei region, and suggest a high degree of background variability in mussel population structure.
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Age, growth and reproduction of largemouth bass, Micropterus salmoides, in Lake Manyame, Zimbabwe

- Beamish, C A, Booth, Anthony J, Deacon, N

Authors: Beamish, C A , Booth, Anthony J , Deacon, N
Date: 2005
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/446770 , vital:74559 , https://doi.org/10.1080/15627020.2005.11407310
Description: A total of 478 largemouth bass, Micropterus salmoides (Lacépède, 1802), was sampled between September 1997 and July 2001 using hook-and-line in Lake Manyame, a water supply reservoir situated outside Harare, Zimbabwe. Male fish dominated the samples, possibly an effect of aggressive behaviour towards the sampling gear used. Ages, determined from sectioned sagittal otoliths, ranged from one to nine years with 94% of the sample being between one and four years of age. An annulus was deposited in late-winter/early spring. Female fish, despite being the largest fish sampled, were found to grow at a significantly slower rate than males. Growth was modelled with the von Bertalanffy model as L(t)=37.22(1–exp(–0.66t)) cm SL for males, and L(t) = 48.16(1–exp(–0.41t)) cm SL for females. All fish matured after one year, thereafter they spawned over a four-month period between July and October. Reproductive activity peaked in August. Largemouth bass has successfully colonized freshwater bodies in southern Africa where it has been introduced, causing significant ecological damage to the indigenous ichthyofauna. Given its ability to grow to a large size, and live to an old age and to breed successfully, further introductions should be viewed with extreme caution.
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