No abstract / Mini Dissertation (LLM)--University of Pretoria, 2019. / Public Law / LLM / Unrestricted

This thesis focused on the interpretation of environmental data obtained from chemical analyses of complex and divergent environmental media. Environmental monitoring of pollutants yields large datasets which may be difficult to process using simplistic univariate approaches. Polycyclic aromatic hydrocarbons (PAH) are environmental organic contaminants that have important health implications and are ubiquitous in the environment. These compounds are regularly monitored in all environmental compartments but delineating their impacting sources from analytical data is usually challenging and thus not routinely attempted. The work contained in this thesis discusses how source information can be obtained by the application of (a) qualitative relationships, (b) physico-chemical models dealing with phase change and partitioning, as well as (c) receptor models using factor analysis to P AH data collected in samples from the atmosphere and in suspended sediments. There are unique concepts and new applications embodied in this thesis. They include: (a) The development and definition of a new diagnostic relationship that discriminates between industrial and urban sources of P AH, (b) the integration of qualitative diagnostic correlations with measured concentration data to improve the diagnostic potential of these simple non-multivariate relationships, (c) the integration of local meteorological data with receptor modeling using factor analysis to explicitly identify impacting PAH source regions, and finally (d) the first known instance of the use of a hybridized receptor modeling methodology to explicitly identify, quantify and spatially map the potential source regions of P AH on a hemispheric scale. An additional effect of the work contained herein is that it shows how much information which could be useful to environmentalists and policy-makers in designing effective abatement and control strategies if available is usually left un-extracted from environmental monitoring activities. / Thesis / Doctor of Philosophy (PhD)

Investigate the interaction of nanomaterials with biological systems, known as nano-bio interaction is of great interest for the assessment of the concern arising from nanomaterials progressive use. Such interaction determines nanomaterials potential effect on human and environment becomes more and more important to understand how they interact with living organisms and the environment. The novel physicochemical characteristics of nanomaterials, such as their small size, large surface area to volume ratio and surface energy, may initiate new toxicological effects due to nanomaterials ability to enter into the biological systems through adsorption and dissolution and modify the structure of various macromolecules An example of these interactions is the adsorption of proteins on nanoparticles surface forming what is known as the 'protein corona'. Therefore, being able to understand how these molecules and other biologically important species are adsorbed and interact, should help us to reduce any adverse impacts of nanoparticles on human health and the environment. Due to the importance of surface composition and surface functionality in nanotoxicology, analytical tools that can probe the change in the structure and composition of the nanoparticles in aqueous media are crucial but remain limited. Therefore in this work, in situ characterization of the liquid–solid interface to probe surface adsorption of environmentally and biologically relevant media on nanoparticle surfaces has been conducted. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy provides the molecular information that allows for the determination of the adsorption mode such as conformational and structural changes of the coordinating ligand. Surface adsorption of titanium dioxide (TiO2) nanoparticles have been investigated in different biological media typically used for toxicity studies and show that the surface composition of TiO2 nanoparticles depends to a large extent on the composition of the medium due to surface adsorption. Moreover, hydrodynamic diameter and surface charge of TiO2 NPs were evaluated using dynamic light scattering DLS. The results indicated that TiO2 NPs undergo different trends in aggregation upon the adsorption of biological media on its surface and zeta potential measurements showed surface charge alterations which are consistent with the aggregation study. In order to understand the dynamic transformations of nanomaterials in biological environments, the effect of dissolution has been predicted. Copper oxide CuO and zinc oxide ZnO nanoparticles were used to study dissolution due to their instability in biological media. Once these particles exposed to solutions they release their ions and tend to aggregate. Therefore, the dissolution of these materials was conducted at size ca. 24 nm and nanoparticles coated with proteins and humic acid employing simulated lung fluids as models to develop a better understanding of how these properties effect the solubility and stability in biological systems. From this study, it was found that both copper oxide and zinc oxide NPs showed different trends in dissolution. Cu and Zn ions once coated with proteins and HA highly dissolved in ALF at low pH 4.5 compared with other fluids (Gamble’s solution and water) at extracellular pH which shows only slightly enhanced in the basal condition. The acidity of ALF may explain the higher solubility of metals that are phagocytized versus those that remain extracellular. Some general conclusions can be drawn from these investigations. It seems that analytical tools to characterize the interfacial region between nanopaerticles and these complex systems provide a reasonably good qualitative and quantitative description of the interactions.

Operatic Mysticisms: Mountains, Deserts, Waterscapes examines the ways we encounter environments as readers/viewers of operas, literature, film, and sound recordings, and how each medium requires different detail-gathering techniques. Respective to the previously mentioned mediums, Sun & Sea (2017), Mount Analogue (1952), El Mar La Mar (2017), and Energy Field (2010) are analyzed by engaging with environmental media studies and invention. Reflecting the nature of each landscape—summits of mountains, aporias of deserts, and mysteries of waterscapes—an elemental approach is taken in investigating how these spaces may be noticed, internalized, recorded, and traversed by both the artist and viewer. With an emphasis on limitations of mediums, language, and equipment, this thesis argues that artists/readers/viewers in turn inhabit these rendered environments—while a looped response (termed as operatic mysticism) threads ekphrasis and imagination before and during the production, in the art proper, and in our minds during and well-after consumption.

In Ethiopia people are highly dependent on natural resources which often lead to environmental degradation. The perception is that environmental degradation is partly due to lack of environmental awareness. The level of environmental awareness and the role of the media in creating awareness in Kembata Tembaro Administrative zone were investigated. Quantitative and qualitative methodologies were used to identify sources of environmental knowledge, content, spatial extent, volume and priority of media coverage, impact of media, and expectation of audiences and producers. Experience, rather than outside sources, such as provided by the media, is the main source of environmental information, but awareness is key to reduce further environmental degradation. Environmental media programs should be transmitted at suitable times and the experiences of successful farmers in natural resources conservation and development should be shared. Attention should also be given to identification of awareness obstacles and training and sensitizing of journalists on environment issues

In Ethiopia people are highly dependent on natural resources which often lead to environmental degradation. The perception is that environmental degradation is partly due to lack of environmental awareness. The level of environmental awareness and the role of the media in creating awareness in Kembata Tembaro Administrative zone were investigated. Quantitative and qualitative methodologies were used to identify sources of environmental knowledge, content, spatial extent, volume and priority of media coverage, impact of media, and expectation of audiences and producers. Experience, rather than outside sources, such as provided by the media, is the main source of environmental information, but awareness is key to reduce further environmental degradation. Environmental media programs should be transmitted at suitable times and the experiences of successful farmers in natural resources conservation and development should be shared. Attention should also be given to identification of awareness obstacles and training and sensitizing of journalists on environment issues