University of Johannesburg

About: University of Johannesburg is a education organization based out in Johannesburg, South Africa. It is known for research contribution in the topics: Population & Tourism. The organization has 8070 authors who have published 22749 publications receiving 329408 citations. The organization is also known as: UJ.

Performance of the ATLAS Trigger System in 2010

Abstract: Proton-proton collisions at root s = 7 TeV and heavy ion collisions at root(NN)-N-s = 2.76 TeV were produced by the LHC and recorded using the ATLAS experiment's trigger system in 2010. The LHC is designed with a maximum bunch crossing rate of 40 MHz and the ATLAS trigger system is designed to record approximately 200 of these per second. The trigger system selects events by rapidly identifying signatures of muon, electron, photon, tau lepton, jet, and B meson candidates, as well as using global event signatures, such as missing transverse energy. An overview of the ATLAS trigger system, the evolution of the system during 2010 and the performance of the trigger system components and selections based on the 2010 collision data are shown. A brief outline of plans for the trigger system in 2011 is presented.

The role of nanomaterials as effective adsorbents and their applications in wastewater treatment

Abstract: Nanomaterials have been extensively studied for heavy metal ions and dye removals from wastewater. This article reviews the role of nanomaterials as effective adsorbents for wastewater purification. In recent years, numerous novel nanomaterial adsorbents have been developed for enhancing the efficiency and adsorption capacities of removing contaminants from wastewater. The innovation, forthcoming development, and challenges of cost-effective and environmentally acceptable nanomaterials for water purification are discussed and reviewed in this article. This review concludes that nanomaterials have many unique morphological and structural properties that qualify them to be used as effective adsorbents to solve several environmental problems.

ZnO/Ag/Mn2O3 nanocomposite for visible light-induced industrial textile effluent degradation, uric acid and ascorbic acid sensing and antimicrobial activity

Abstract: A facile and inexpensive route has been developed to synthesize a ternary ZnO/Ag/Mn2O3 nanocomposite having nanorod structures based on the thermal decomposition method. The as-synthesized ternary ZnO/Ag/Mn2O3 nanocomposite was characterized and used for visible light-induced photocatalytic, sensing and antimicrobial studies. The ternary ZnO/Ag/Mn2O3 nanocomposite exhibited excellent and enhanced visible light-induced photocatalytic degradation of industrial textile effluent (real sample analysis) compared to pure ZnO. Sensing studies showed that the ternary ZnO/Ag/Mn2O3 nanocomposite exhibited outstanding and improved detection of uric acid (UA) and ascorbic acid (AA). It also showed effective and efficient bactericidal activities against Staphylococcus aureus and Escherichia coli. These results suggest that the small size, high surface area and synergistic effect among ZnO, AgNPs and Mn2O3 induced visible light photocatalytic activity by decreasing the recombination of photogenerated electrons and holes, and extending the response of pure ZnO to visible light, enhanced sensing of UA and AA and antimicrobial activity. Overall, the ternary ZnO/Ag/Mn2O3 nanocomposite is a valuable material that can be used for a range of applications, such as visible light-induced photocatalysis, sensing and antimicrobial activity. Therefore, ternary nanocomposites could have important applications in environmental science, sensing, and biological fields.

Origin of angiosperms and the puzzle of the Jurassic gap

Abstract: Angiosperms are by far the most species-rich clade of land plants, but their origin and early evolutionary history remain poorly understood. We reconstructed angiosperm phylogeny based on 80 genes from 2,881 plastid genomes representing 85% of extant families and all orders. With a well-resolved plastid tree and 62 fossil calibrations, we dated the origin of the crown angiosperms to the Upper Triassic, with major angiosperm radiations occurring in the Jurassic and Lower Cretaceous. This estimated crown age is substantially earlier than that of unequivocal angiosperm fossils, and the difference is here termed the ‘Jurassic angiosperm gap’. Our time-calibrated plastid phylogenomic tree provides a highly relevant framework for future comparative studies of flowering plant evolution. A study reconstructed angiosperm phylogeny on the basis of plastome data representing 2,351 angiosperm and 187 gymnosperm species, and dated the origin of crown angiosperms to be significantly earlier than the estimates based on fossil data.

Trends and challenges of traditional medicine in Africa.

Abstract: Prior to the introduction of cosmopolitan medicine, traditional medicine used to be the dominant medical system available to millions of people in Africa in both rural and urban communities However, the arrival of the Europeans marked a significant turning point in the history of this age-long tradition and culture This paper examines the trends and challenges of traditional medicine in Africa The impact of colonialism on African traditional medicine is also examined Although the paper is on Africa, references are drawn around the world to buttress the growing demand for traditional medicine The paper concludes that to minimise the current distrust between modern and traditional doctors and to achieve the objective of regulation, standardisation and cooperation, both traditional and modern doctors must acknowledge their areas of strengths and weaknesses from which they operate and be genuinely concerned about the difficult but necessary task of being human