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Pretoria, South Africa

Tshwane University of Technology is a higher education institution in South Africa that came into being through a merger of three technikons — Technikon Northern Gauteng, Technikon North-West and Technikon Pretoria.As the number of students registering annually grows rapidly, records show that Tshwane University of Technology caters for approximately 60,000 students and it has become the largest residential higher education institution in South Africa. Wikipedia.

Funston P.J.,Tshwane University of Technology
South African Journal of Wildlife Research | Year: 2011

Lions (Panthera leo) that kill livestock around the Kgalagadi Transfrontier Park have been persecuted for decades. The impact of this on the population ecology and long-term survival probability of this population has been unknown. This was largely due to a lack of basic population information. The results of a three-year intensive study from 1998 to 2001 into the population characteristics of Kgalagadi lions are presented. Kgalagadi lions exhibit similar population characteristics to most other lion populations and show little to no effect of anthropogenic mortality. Differences from other populations include exceptionally large home ranges (1462 ± 388 km 2), which are however related to prey biomass. The adult sex ratio was more biased towards females than is typical, which is possibly a product of both ecological and anthropogenic influences. Cub survival is related to rainfall conditions and the number of adult lionesses in groups with cubs, but not to the number of adult males defending each pride. Owing to low prey abundance prides form stable subgroups typically containing two adult lionesses for long periods once cubs have reached one year of age. Kgalagadi lions show similar dispersal patterns to other lion populations with resident prey. Subadults in boundary prides suffer high mortality levels in response to livestock depredation. Males are more likely to become habitual livestock raiders, which ultimately leads to them being killed.

Diesel engines provide the major power source for transportation in the world and contribute to the prosperity of the worldwide economy. However, recent concerns over the environment, increasing fuel prices and the scarcity of fuel supplies have promoted considerable interest in searching for alternatives to petroleum based fuels. Based on this background, the main purpose of this investigation is to evaluate clove stem oil (CSO) as an alternative fuel for diesel engines. To this end, an experimental investigation was performed on a four-stroke, four-cylinder water-cooled direct injection diesel engine to study the performance and emissions of an engine operated using the CSO-diesel blended fuels. The effects of the CSO-diesel blended fuels on the engine brake thermal efficiency, brake specific fuel consumption (BSFC), specific energy consumption (SEC), exhaust gas temperatures and exhaust emissions were investigated. The experimental results reveal that the engine brake thermal efficiency and BSFC of the CSO-diesel blended fuels were higher than the pure diesel fuel while at the same time they exhibited a lower SEC than the latter over the entire engine load range. The variations in exhaust gas temperatures between the tested fuels were significant only at medium speed operating conditions. Furthermore, the HC emissions were lower for the CSO-diesel blended fuels than the pure diesel fuel whereas the NO. x emissions were increased remarkably when the engine was fuelled with the 50% CSO-diesel blended fuel. © 2010 Elsevier Ltd.

Bolaji B.O.,Abeokuta Federal University of Agriculture | Huan Z.,Tshwane University of Technology
Renewable and Sustainable Energy Reviews | Year: 2013

This paper presents natural refrigerants as the ideal, environmentally friendly refrigerants and the ultimate solution to the problems of ozone depletion and global warming. HFC refrigerants are currently the leading replacement for CFC and HCFC refrigerants in refrigeration and air-conditioning systems. However, they are equally foreign to nature like CFCs and HCFCs, consequently, strong basis for the need to embrace the use of natural refrigerants as replacement for the halocarbon refrigerants was provided. This paper also analyses potentials of various natural refrigerants and their areas of application in refrigeration and air-conditioning systems. Natural refrigerants especially hydrocarbons and their mixtures are miscible with both mineral oil used in R12 and poly-ol-ester oils used in R134a systems. Also, with exception of ammonia, they are fully compatible with all materials traditionally used in refrigeration systems. Finally, this paper has revealed that natural refrigerants are the most suitable long time alternatives in refrigeration and air-conditioning systems. © 2012 Published by Elsevier Ltd.

Sivakumar D.,Tshwane University of Technology | Bautista-Banos S.,National Polytechnic Institute of Mexico
Crop Protection | Year: 2014

Postharvest diseases are one of the major causes for the postharvest loss of horticultural fresh produce during the supply chain. The incidence of postharvest diseases can affect the quality and restrict the shelf life of the horticultural fresh produce. At present strict regulations are enforced by the fresh produce importing countries regarding the minimum pesticide residue levels in the edible portion of the fresh produce. Some fungal pathogens were reported to develop resistance to synthetic fungicides. Waste disposal of fungicides has an impact on environmental footprint. All theses above-mentioned reasons have necessitated the search for a natural novel fungicide to replace the synthetic fungicide application in the packing line as postharvest treatment.Consumer preference to organic fresh produce is increasingly becoming popular in the developed countries. Therefore, this review summarises the use of essential oils in the control of postharvest diseases of horticultural commodities, their mode of actions, effects on the defence mechanism and quality of fresh fruit. Future research must be focused on conducting large scale trials to prove the feasibility of combination treatments. The cost benefit analysis of the treatments needs to be carried out in order to implement their application and the commercial applications of essential oils and host pathogen infection must be investigated in detail in order to control latent infections during postharvest storage. © 2014 Elsevier Ltd.

Ruxwana N.L.,Tshwane University of Technology
The HIM journal | Year: 2010

Information and Communication Technology (ICT) solutions (e.g. e-health, telemedicine, e-education) are often viewed as vehicles to bridge the digital divide between rural and urban healthcare centres and to resolve shortcomings in the rural health sector. This study focused on factors perceived to influence the uptake and use of ICTs as e-health solutions in selected rural Eastern Cape healthcare centres, and on structural variables relating to these facilities and processes. Attention was also given to two psychological variables that may underlie an individual&s acceptance and use of ICTs: usefulness and ease of use. Recommendations are made with regard to how ICTs can be used more effectively to improve health systems at fi ve rural healthcare centres where questionnaire and interview data were collected: St. Lucy&s Hospital, Nessie Knight Hospital, the Tsilitwa Clinic, the Madzikane Ka-Zulu Memorial Hospital and the Nelson Mandela General Hospital.

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