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 & Context (language use). The organization has 8070 authors who have published 22749 publications receiving 329408 citations. The organization is also known as: UJ.

Testing thermal reprocessing in AGN accretion discs

Abstract: The thermal reprocessing hypothesis in AGN, where EUV/X-ray photons are reprocessed by the accretion disc into optical/UV photons, predicts wavelength-dependent time delays between the optical continuum at different wavelengths. Recent photometric monitoring by Sergeev et al. has shown that the time-delay is observed in 14 AGN, and generally seen to increase with increasing wavelength, as predicted in the reprocessing scenario. We fit the observed time delays and optical spectral energy distribution using a disc reprocessing model. The model delivers estimates for the nuclear reddening, the product of black hole mass times accretion rate, and the distance to each object. However, the distances at face value give H_0 = 44 +/- 5 km/s/Mpc - a factor of 1.6 smaller than generally accepted. We discuss the implications of this on the reprocessing model.

Impact of Fermentation on the Phenolic Compounds and Antioxidant Activity of Whole Cereal Grains: A Mini Review.

Abstract: Urbanization, emergence, and prominence of diseases and ailments have led to conscious and deliberate consumption of health beneficial foods. Whole grain (WG) cereals are one type of food with an array of nutritionally important and healthy constituents, including carotenoids, inulin, β-glucan, lignans, vitamin E-related compounds, tocols, phytosterols, and phenolic compounds, which are beneficial for human consumption. They not only provide nutrition, but also confer health promoting effects in food, such as anti-carcinogenic, anti-microbial, and antioxidant properties. Fermentation is a viable processing technique to transform whole grains in edible foods since it is an affordable, less complicated technique, which not only transforms whole grains but also increases nutrient bioavailability and positively alters the levels of health-promoting components (particularly antioxidants) in derived whole grain products. This review addresses the impact of fermentation on phenolic compounds and antioxidant activities with most available studies indicating an increase in these health beneficial constituents. Such increases are mostly due to breakdown of the cereal cell wall and subsequent activities of enzymes that lead to the liberation of bound phenolic compounds, which increase antioxidant activities. In addition to the improvement of these valuable constituents, increasing the consumption of fermented whole grain cereals would be vital for the world’s ever-growing population. Concerted efforts and adequate strategic synergy between concerned stakeholders (researchers, food industry, and government/policy makers) are still required in this regard to encourage consumption and dispel negative presumptions about whole grain foods.

Industry 4.0 and supply chain sustainability: framework and future research directions

Abstract: The evolution of technology from the most recent industrial age to the technology era better known as Industry 4.0 resulted in greater demand for horizontal, vertical and end-to-end digital integration. Prior studies show that Industry 4.0 adoption majorly influences the sustainability aspects in a supply chain network. The purpose of this paper is to identify the Industry 4.0 enablers of supply chain sustainability and further attempt to propose a research framework to bridge the theoretical gaps.,In this research study, the authors have used a systematic literature review methodology in the field of Industry 4.0 and sustainable supply chain management. The list of papers was downloaded from Scopus (www.scopus.com) database. Through strict screening, only journal papers were selected for conducting the review of the literature.,The review brings out some interesting findings which will be helpful for the research community. There have been limited research in the area of managing supply chain network sustainability through Industry 4.0 technologies. The authors found only 10 papers out of a total of 53 papers which emphasize on smart manufacturing, smart production system, smart warehouse management system, smart logistics and sustainability. Most of the previous research studies have ignored the social aspects of supply chain sustainability. Finally, the authors identified 13 key enablers of Industry 4.0 playing an important role in driving supply chain sustainability.,The strategies for Industry 4.0 should be refined and detailed to develop economic and social systems that can act flexibly to sudden changes in the system. Top management must be convinced for prioritizing investment support and creating a system that can facilitate technology convergence. Managers must also act on new models of employment and frame plans to continuously improve the system. In addition, managers must focus on establishing a collaborative platform to facilitate high-tech research and developments. Finally, it is essential to develop a performance management system for monitoring all actions in the supply chain network.,Integrating two independent subjects is the uniqueness of the current study. Here, Industry 4.0 and supply chain sustainability have been integrated to build the research framework, and in such a process, the authors have extended the existing knowledge base.

Study of the rare decays of B s 0 and B 0 mesons into muon pairs using data collected during 2015 and 2016 with the ATLAS detector

Abstract: A study of the decays B0 s ! + and B0 ! + has been performed using 26 : 3 fb of 13TeV LHC proton-proton collision data collected with the ATLAS detector in 2015 and 2016. Since the detector resolut ...

Performance of electron and photon triggers in ATLAS during LHC Run 2

Abstract: Electron and photon triggers covering transverse energies from 5 GeV to several TeV are essential for the ATLAS experiment to record signals for a wide variety of physics: from Standard Model processes to searches for new phenomena in both proton–proton and heavy-ion collisions. To cope with a fourfold increase of peak LHC luminosity from 2015 to 2018 (Run 2), to 2.1×1034cm-2s-1, and a similar increase in the number of interactions per beam-crossing to about 60, trigger algorithms and selections were optimised to control the rates while retaining a high efficiency for physics analyses. For proton–proton collisions, the single-electron trigger efficiency relative to a single-electron offline selection is at least 75% for an offline electron of 31 GeV, and rises to 96% at 60 GeV; the trigger efficiency of a 25 GeV leg of the primary diphoton trigger relative to a tight offline photon selection is more than 96% for an offline photon of 30 GeV. For heavy-ion collisions, the primary electron and photon trigger efficiencies relative to the corresponding standard offline selections are at least 84% and 95%, respectively, at 5 GeV above the corresponding trigger threshold.