University of the Free State

About: University of the Free State is a education organization based out in Bloemfontein, South Africa. It is known for research contribution in the topics: Population & Photoluminescence. The organization has 8429 authors who have published 16531 publications receiving 240919 citations. The organization is also known as: UFS.

Revealing x-ray and gamma ray temporal and spectral similarities in the GRB 190829A afterglow

Abstract: Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, are associated with stellar core collapse events. We report the detection of very-high-energy (VHE) gamma rays from the afterglow of GRB 190829A, between 4 and 56 hours after the trigger, using the High Energy Stereoscopic System (H.E.S.S.). The low luminosity and redshift of GRB 190829A reduce both internal and external absorption, allowing determination of its intrinsic energy spectrum. Between energies of 0.18 and 3.3 tera–electron volts, this spectrum is described by a power law with photon index of 2.07 ± 0.09, similar to the x-ray spectrum. The x-ray and VHE gamma-ray light curves also show similar decay profiles. These similar characteristics in the x-ray and gamma-ray bands challenge GRB afterglow emission scenarios.

Positive spill-over effects of ART scale up on wider health systems development: evidence from Ethiopia and Malawi

Abstract: Background Global health initiatives have enabled the scale up of antiretroviral treatment (ART) over recent years. The impact of HIV-specific funds and programmes on non-HIV-related health services and health systems in genera has been debated extensively. Drawing on evidence from Malawi and Ethiopia, this article analyses the effects of ART scale-up interventions on human resources policies, service delivery and general health outcomes, and explores how synergies can be maximized.

South African life orientation teachers: (not) teaching about sexuality diversity.

Abstract: Although South Africa is one of the most progressive countries in the world in terms of constitutional and legislative rights for LGBT individuals, education is one of many social arenas where these ideals are not carried out. Interviews with 25 practicing teachers revealed very little description of practice, but widely divergent understandings around sexual diversity that drew on various authoritative discourses, including religious teachings, educational policy, science, and the powerful human rights framework of the South African constitution. Implications for teacher education include directly engaging with these discourses and providing training, teaching materials, and practical guidelines based on existing policy.

Association of parental genetic distance with heterosis and specific combining ability in quality protein maize

Abstract: Genetic distance analysis among quality protein maize (QPM) inbred lines and the correlation of genetic distance with heterosis would help to design breeding strategy and predict hybrid performance. This study was carried out to determine the amount of genetic diversity among QPM inbred lines using SSR markers and morphological distances; to classify the inbred lines according to their relationships; and to estimate the correlations of SSR markers and morphological distances with hybrid performance, heterosis and specific combining ability (SCA). One-hundred and five hybrids generated by diallel crossing of 15 QPM inbred lines were evaluated with the 15 parents for 17 morphological traits at Harare, Zimbabwe and Bako, Ethiopia and also examined for DNA polymorphism using 40 SSR markers. SSR markers and morphological methods of genetic distance estimates showed moderately high genetic distance among the inbred lines studied. Cluster analysis based on the two distance measures grouped the 15 parental lines differently. The SSR marker-based genetic distance was positively and highly significantly correlated with grain yield (r = 0.37), and negatively and highly significantly with days to anthesis (r = −0.40) and days to silking (r = −0.42). These relationships suggest that high grain yield and earliness of QPM hybrids can be predicted from SSR marker determined distances of the parents, although the correlation values were not very high. The correlations of SSR marker distance with heterosis were too low to be of predictive value except for the case of plant height. Morphological distances were of less importance in predicting hybrid performance and SCA effects of hybrids.