Latest News Archive

Please select Category, Year, and then Month to display items
Previous Archive
10 December 2018 | Story Leonie Bolleurs | Photo Leonie Bolleurs
One step closer to treat HIV/Aids
Nthabiseng Mokoena is working on an article based on her research about drug development in infection models, which will be published under the Research Chair in Pathogenic Yeasts.

South Africa has the biggest and most high-profile HIV epidemic in the world, with an estimated seven million people living with HIV in 2015. In the same year, there were 380 000 new infections while 180 000 South Africans died from AIDS-related illnesses. 

Invasive fungal infection, common in certain groups of patients with immune deficits, is a serious driver of global mortality in the context of the global HIV pandemic. 

“Despite a major scientific effort to find new cures and vaccines for HIV, hundreds of thousands of HIV-infected individuals continue to die on a yearly basis from secondary fungal infection. Intensive research needs to be done to help reduce the unacceptably high mortality rate due to the infection in South Africa,” said Nthabiseng Mokoena.

Mokoena is a master’s student of Prof Carlien Pohl-Albertyn, who is heading the Research Chair in Pathogenic Yeasts in the Department of Microbial, Biochemical and Food Biotechnology at the University of the Free State (UFS). 

She received her master’s degree at the December graduations of the UFS. Her thesis is titled: Caenorhabditis elegans as a model for Candida albicans-Pseudomonas aeruginosa co-infection and infection induced prostaglandin production.

Research Chair in Pathogenic Yeasts

Earlier this year, the National Research Foundation approved the Research Chair in Pathogenic Yeasts. One of the projects of the group of scientists in this chair include a study of the interaction between the yeast, Candida albicans and the bacterium, Pseudomonas aeruginosa in different hosts, using a variety of infection models.

In her research, Mokoena studied the response of infectious pathogens such as yeasts and bacteria, using a nematode (little roundworm) as an infection model to mimic the host environment. Nematodes have a number of traits similar to humans. It is thus a good alternative for humans as infection models, as it is unethical to use the latter.

Nematodes have a number of advantages, including its low cost and fast reproduction and growth. 

Mokoena monitored the survival of the nematodes to see how infectious the pathogens are, especially in combination with each other. 

Role of infection model for drug development

When these two pathogens were studied in a lab (in vitro), it was found that they can inhibit each other, but after studying them in the infection model (in vivo), Mokoena showed that these pathogens are more destructive together. 

This finding has a huge impact for the pharmaceutical industry, as it can provide information on how drugs need to be designed in order to fight infectious diseases where multiple organisms cause co-infections.

Many pathogens are resistant to drugs. Through this model, drugs can be tested in a space similar to the human body. Seeing how pathogens react to drugs within a space similar to the human body, can contribute to drug development. 

Not only are drugs developed more effectively through this model, it is also less expensive. 

It is the first time that the combination of the yeast, Candida albicans and the bacterium, Pseudomonas aeruginosa, is being experimented on in this model. 

News Archive

Research helps farmers save with irrigation
2017-02-15

Description: Irrigation research Tags: Irrigation research

Marcill Venter, lecturer in the Department of
Agricultural Economics at the University of the
Free State, has developed the mathematical
programming system, Soil Water Irrigation
Planning and Energy Management in order to
determine irrigation pump hours.
Photo: Rulanzen Martin

Her advice to farmers is that they should make sure they are aware of the total cost (investment and operating costs) of an irrigation system. In most cases the investment cost is low, but the operating cost over the lifetime of the system is high.

“It is very important to have a look at the total cost and to install the most economic system,” says Marcill Venter, lecturer at the University of the Free State (UFS), who has done research on the economic sustainability of water-pipe systems.

Irrigation systems important components for farming
This research comes at a time when many farmers are relying on their irrigation systems due to persistent drought and low rainfall during 2016. South Africa has also experienced an abnormal increase in electricity tariffs in recent years. Due to tariff increases which threaten the future profitability of irrigation producers, the Water Research Commission (WRC) has launched and financed a project on the sustainable management of irrigation farming systems. “I had the opportunity to work on the project as a researcher,” says Venter.

The heart of every irrigation system is the water pipes that bring life to crops and livestock, and this is what Venter’s research is about. “Water pipes are part of the whole design of irrigation systems. The design of the system impact certain factors which determine the investment and operating costs,” she says.

Mathematical system to help farmers
Venter and Professor Bennie Grové, also from the Department of Agricultural Economics at the UFS, designed the Soil Water Irrigation Planning and Energy Management (SWIP-E) programming model as part of the WRC’s project, as well as for her master’s degree. “The model determines irrigation pump hours through a daily groundwater budget, while also taking into account the time-of-use electricity tariff structure and change in kilowatt requirements arising from the main-line design,” says Venter. The model is a non-linear programming model programmed in General Algebraic Modeling System (GAMS).

Design of irrigation system important for sustainability

The main outcome of the study is that the time-of-use electricity tariff structure (Ruraflex) is always more profitable than the flat-rate structure (Landrate). The interaction between the management and design of a system is crucial, as it determines the investment and operating costs. Irrigation designers should take the investment and operating cost of a system into account during the design process. The standards set by the South African Irrigation Institute (SAII) should also be controlled and revised.

Water-pipe thickness plays major role in cost cuts
There is interaction between water-pipe thickness, investment and operating costs. When thinner water pipes are installed, it increases the friction in the system as well as the kilowatt usage. A high kilowatt increases the operating cost, but the use of thinner water pipes lowers the investment cost. Thicker water pipes therefore lower the friction and the kilowatt requirements, which leads to lower operating costs, but thicker pipes have a higher investment cost. “It is thus crucial to look at the total cost (operating and investment cost) when investing in a new system. Farmers should invest in the system with the lowest total cost,” says Venter.

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept