Author:Thwala, Melusi; Musee, N; Wepener, V; Nota, NDate:Apr 2012The toxicity of engineered nanoparticles towards macro algae and higher aquatic plants has not been well studied. This knowledge gap challenges the development of nano risk assessment towards water ecosystems. In this study, we investigated ...Read more
Author:Oosthuizen, MA; John, J; Somerset, VernonDate:01 Sep 2010South Africa relies mainly on coal for its energy needs. In addition, the country is one of the main producers of gold. Both coal combustion and gold mining are sources of mercury pollution, contributing to South Africa being one of the leading ...Read more
Author:Ramond, JB; Lako, JDW; Stafford, William HL; Tuffin, MI; Cowan, DADate:Feb 2015Ammonia-oxidizing bacteria (AOB) are essential in the biogeochemical cycling of nitrogen as they catalyze the rate-limiting oxidation of ammonia into nitrite. Since their first isolation in the late 19th century, chemolithoautotrophic AOBs ...Read more
Author:Van Wilgen, BDate:2012The Table Mountain National Park is a 265 km2 protected area embedded within a city of 3.5 million people. The park contains an extremely diverse flora with many endemic species, and has been granted World Heritage Site status in recognition ...Read more
Author:Van Heerden, Quintin; Van Vuuren, JDate:Dec 2022Sustainable development is at the heart of city planning, and urbanisation plays a central role in achieving the Sustainable Development Goals. Urbanisation, however, is interlaced with existential challenges such as climate change. The ...Read more
Author:Funke, Nicola S; Shaxson, L (ed); Bielak, AT (ed)Date:Mar 2009This handbook summarises the background behind, format of and lessons learned from a Collaborative Workshop on Evidence-based Policy-making that was held in November 2008. The workshop was organised by CSIR and funded by the UK's Department ...Read more
Author:Roux, FS; Wellens, T; Shatokhin, VDate:Jun 2015Recently, an infinitesimal propagation equation was derived for the evolution of orbital angular momentum entangled photonic quantum states through turbulence. The authors will discuss its derivation and application within both classical and ...Read more
Author:Duvenhage, A; Terblanche, LDate:Jun 2008Live, Virtual and Constructive (LVC) simulations can share tactical awareness data using command and control (C2) protocol gateways as bridges: Multiple training simulations can be linked to create large scale collaborative environments; ...Read more
Author:de Waal, ADate:Jun 2006The aim of this study is to evaluate the discovery of temporal themes in a text stream. The authors evaluate a probabilistic model for unsupervised learning to solve the problem and a scheme for theme evolution visualisation is proposed. The ...Read more
Author:Veerasamy, NamoshaDate:Mar 2022A Cybersecurity Operation Centre (SOC) is a centralized hub within an organisation that houses people, processes, and technologies aimed at continuous monitoring of the organization’s assets in order to prevent, detect, analyse, and respond ...Read more
Author:Van Wilgen, BWDate:Sep 2009The history and development of fire and invasive alien plant management policies in fynbos during the 20th century are reviewed. Fire was initially condemned outright as a destructive force, but as its vital role became better understood, ...Read more
Author:Archibald, S; Staver, C; Levin, SADate:Jan 2012Human ability to manipulate fire and the landscape has increased over evolutionary time, but the impact of this on fire regimes and consequences for biodiversity and biogeochemistry are hotly debated. Reconstructing historical changes in ...Read more
Author:Roux, FS; Wellens, T; Shatokhin, VDate:Aug 2015The evolution of the quantum states of photons propagating through turbulence can be investigated with the infinitesimal propagation equation (IPE). However, when it is expressed directly in terms of an orbital angular momentum (OAM) basis, ...Read more
Author:Roux, FSDate:Jan 2011Stochastic vortex fields are found in laser speckle, in scintillated beams propagating through a turbulent atmosphere, in images of holograms produced by Iterative Fourier Transform methods and in the beams produced by certain diffractive ...Read more
Author:Roux, FSDate:Jan 2011Orbital angular momentum (OAM) entangled bi-photons are a resource for the higher dimensional implementation of quantum cryptography, which allows secure communication over various channels. In the case where free-space is used as communication ...Read more
Author:Roux, FS; Chen, MDate:Sep 2010In an attempt to understand the process whereby the phase modulation due to atmospheric turbulance causes phase singularities (also called optical vortices), the authors investigated the effect of phase perturbations in speckle beams. They ...Read more
Author:Chen, M; Roux, FSDate:Oct 2010Knowledge of the behavior of stochastic optical fields can aid the understanding of the scintillation of light propagating through a turbulent medium. For this purpose, the authors perform a numerical investigation of the evolution of the ...Read more
Author:Pieterse, Heloise; Burke, Ivan DDate:Mar 2015Smartphones continue to excel in the 21st century due to the constant improvements of mobile technology. Advances in smartphones, such as increased computing power, improved device-to-device communication and the option of installing additional ...Read more