Scopus
Permanent URI for this collection
Browse
Recent Submissions
Item Sublethal effects of insecticides on the reproductive success of the Tsetse species Glossina pallidipes and G. m. morsitans(2010) Kibuka-Sebitosi E.Female Glossina pallidipes Austen and G. m. morsitans Westwood (Diptera: Glossinidae) were treated with deltamethrin or pyrethrum extract through topical application or by exposure to cloth or glass treated with the same insecticides. Reproductive performance was assessed in terms of survival, pupae number and viability and reproductive deformities and abnormalities within the reproductive systems including abortions. Survival and fecundity of treated flies were significantly reduced (P<0.001). Pupae were small, mostly non-viable, and were arrested at various stages of development. Abortions of egg and all stages of larvae were observed in pregnancy cycles 1-7 following insecticide treatment. Various concentrations ranging from 1-1014 nanograms per micro litre (ng/μL) of insecticide in redistilled acetone topically applied (1μ/fly) on the dorsal thorax of the females, 24 hr after their previous blood meal, resulted in both insecticides in various concentrations causing reproductive abnormalities in both species, including egg reabsorption after ovulation. The sublethal effects were observed to prevent ovulation altogether in some of the flies, which implies effects on the reproductive performances and control strategies for tsetse flies. Sublethal doses could impact negatively on beneficial organisms in the environment where tsetse flies occur mainly riverine, woodlands and forest ecosystems.Item Zulu Noun Classes Revisited: A Spoken Corpus-Based Approach(2010) Mtholeni N.N.[No abstract available]Item Art and/as Anarchy: Portraying the artist during times of turmoil and war(2010) Roos H.Two South African novels, Congo Song (Cloete [1943]1973) and Moxyland (Beukes 2008) comment on the central part played by artists and their work in the midst of a society on the brink of war. Both narratives are set in Africa; one portrays a close-knit white community in the Congo in 1939, facing the collapse of their colonial way of life, the other depicts the apocalyptic nature of a dystopian Cape Town around 2018, reflecting the global reality of environmental catastrophe, deadly epidemics and state and corporate tyranny. In both texts art and artists play pivotal roles within a group of characters, and their views of their work, the multiple manifestations of creative art and the relationship between their specific communities and what is regarded there as art, form an integral part of the narrative whole. This article focuses on how various textual strategies are exploited to reveal how the creative urge is linked with resistance against as well as support for destructive violence. It also discusses aspects of the novels that are structured to, on the one hand, endorse the quest for romantic aestheticism and, on the other hand, forecast the reign of cyberspace and genetically modified art. 2011 04 15. © JLS/TLW.Item Flame ionization gas chromatographic determination of phthalate esters in water, surface sediments and fish species in the Ogun river catchments, Ketu, Lagos, Nigeria(2011) Adeniyi A.A.; Okedeyi O.O.; Yusuf K.A.The detection and quantification of four phthalate esters-dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), and diethylhexyl phthalate (DEHP)-in water, sediment, and some fish species were carried out using flame ionization gas chromatography. The samples were collected from the Ogun river catchments, Ketu, Lagos. The DMP was not detected in the water and fish samples but was detected in sediments collected from four of the six sampling sites. The concentration of DEP, DBP, and DEHP in the fish species ranged from 320.0-810.0, 380.0-1,080.0, and 40.0-150.0 μg/kg in Tilapia sp.; 310.0-860.0, 400.0-1,170.0, and 40.0-110.0 μg/kg in Chrysichthys sp.; and 320.0-810.0, 400.0-3,970.0, and 30.0-300.0 μg/kg (DEHP) in Synodontis sp., respectively. The differences in fish phthalate levels are not statistically significant at p∈<∈0.05, an indication that phthalate esters accumulation is not fish species dependent. The DEP, DBP, and DEHP values recorded are considerably higher than the maximum allowed concentrations for drinking water prescribed by the US Environmental Protection Agency. The phthalate pollution index and biosediment accumulation factor values were also calculated. © 2010 Springer Science+Business Media B.V.Item A comparative perspective on teacher attitude-constructs that impact on inclusive education in South Africa and Sweden(2011) Nel N.; Muller H.; Hugo A.; Helldin R.; Backmann O.; Dwyer H.; Skarlind A.This article is based on joint research, between academics from South Africa and Sweden, comparing the influence of South African and Swedish teachers' attitudes towards the practical application of inclusive education (IE) in the classroom. The aim of the study was to identify and investigate problem areas pertaining to teachers' attitudes to IE. Attitudes often relate to interaction with others. This study departs from Festiger's theory of cognitive dissonance, which deals with the influence of people's attitudes and attitude change. In this research teachers from South Africa and Sweden completed the same questionnaire on perceptions pertaining to IE in their school system. A number of attitude-constructs were derived from the data via exploratory factor analysis methodology. Attitude-constructs included policy issues and specialised support; practical implementation of IE; teacher support structures; teachers' receptiveness of IE implementation; feasibility of proposed IE practices; and role of special schools in an IE environment. Negative responses to some of the attitude constructs identified problem areas in Swedish and South African inclusive systems. The comparative nature of the work enabled the researchers to suggest remedial action within each country's socio-economic setting, and in this way affect change in teacher attitudes. © 2011 EASA.