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Bloemfontein, South Africa

The University of the Free State is a multi campus public university in Bloemfontein, the capital of the Free State and the judicial capital of South Africa. Wikipedia.

Marston A.,University of the Free State
Journal of Chromatography A | Year: 2011

Bioautography on thin-layer chromatographic (TLC) plates is a means of detecting the biological activity of a sample which has migrated on the plate with a suitable solvent. It only requires small amounts of sample and is ideal for the investigation of plant constituents, which often occur as complex mixtures. It can be used for the target-directed isolation of these constituents. In contrast to HPLC, many samples can be run at the same time on TLC. Organic solvents, which cause inactivation of enzymes or death of living organisms, can be completely removed before biological detection. Many bioassays are compatible with TLC. Antimicrobial, radical scavenging, antioxidant activities and enzyme inhibition feature among the tests that are employed. © 2010 Elsevier B.V. Source

Grobbelaar J.U.,University of the Free State
Photosynthesis Research | Year: 2010

The maximum quantumyield (φ max), calculated from the maximum chlorophyll a specific photosynthetic rate divided by the quantum absorption per unit chlorophyll a, is 8 photons or 0.125 mol C per mol Quanta light energy. For the average solar radiation that reaches the earth's surface this relates to a photosynthetic yield of 1.79 g(dw m -2 day -1 per percentage photosynthetic efficiency and it could be doubled for sunny, dry and hot areas. Many factors determine volumetric yields of mass algal cultures and it is not simply a question of extrapolating controlled laboratory rates to large scale outdoor production systems. This is an obvious mistake many algal biotechnology start-up companies make. Closed photobioreactors should be able to outperform open raceway pond cultures because of the synergistic enhancement of a reduced boundary layer and short light/dark fluctuations at high turbulences. However, this has not been shown on any large scale and to date the industrial norm for very large production systems is open raceway production ponds. Microalgal biomass production offers real opportunities for addressing issues such as CO 2 sequestration, biofuel production and wastewater treatment, and it should be the preferred research emphasis. © Springer Science+Business Media B.V. 2010. Source

Atangana A.,University of the Free State
Journal of Computational Physics | Year: 2015

In this work, we have generalized the time-fractional telegraph equation using the concept of derivative of fractional variable order. The generalized equation is called time-fractional variable order telegraph equation. This new equation was solved numerically via the Crank-Nicholson scheme. Stability and convergence of the numerical solution were presented in details. Numerical simulations of the approximate solution of the time-fractional variable order telegraph equation were presented for different values of the grid point. © 2014 Elsevier Inc. Source

University of the Free State | Date: 2013-10-30

The present invention relates to the isolation and characterization of a protein responsible for the reduction of uranium (VI) to uranium (IV). The present invention extends to the use of the isolated protein in the reduction of uranium (VI) to uranium (IV) and further extends to a process for the bioremediation, or at least partial remediation, of a site contaminated with a source of U (VI). According to a first aspect thereof, the present invention provides an isolated polypeptide derived from

University of the Free State | Date: 2013-09-06

This invention relates to a mammographic tomography test object (hereinafter referred to as a phantom) and more particularly, but not exclusively, to a mammographic tomography test phantom for use in the verification of image reconstruction positions in digital breast tomosynthesis. The phantom includes a body made from an approximately tissue equivalent x-ray attenuating material; an upper spacer located on top of the body, and a lower spacer located below the body, the spacers being made from a substantially non-compressible material; and a plurality of x-ray opaque granules located at predetermined positions within the body.

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