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Long interspersed nuclear elements-1 (Line-1 or L1) accounts for approximately 17% of the human genome. The majority of L1s are inactive, but ~100 remain retrotransposon competent (RC-L1) and retrotranspose through RNA intermediates to different locations of the genome. It is well established that L1 is involved in both disease initiation and progression via retrotransposition dependent and independent mechanisms. Retrotransposed L1 sequences disrupt loci (e.g. gene structure) in ways that lead to human disease, and activities of L1 si/piRNA, ORF1 and ORF2 proteins are implicated in the etiology and progression of human diseases such as in breast and colon cancer (Miki et al., 1992; Ohms et al., 2014). Despite these implications, very little is known about pharmacological molecules that inhibit and reverse L1’s harmful effects. The clinical utility of L1 as a player in tumorigenesis and as a biomarker for disease initiation and progression is not thoroughly understood. In this review, we analyzed the life cycle of L1, its roles in disease initiation and progression, clinical utilities and potential as a pharmacological target and a biomarker for the diagnosis and treatment of human diseases, such as cancer.

M.Sc. (Chemistry) / Cobalt is mainly associated with copper, both in the primary ores and in the oxidation zone. In Southern Africa cobalt metal is produced as a by-product of the extraction of copper, nickel and platinum group metals. The hydrometallurgical route is commonly used, since cobalt bearing materials are acid leached prior to the clarification and impurity removal process preceding the electrowinning of the value. In order to understand the dissolution behaviour of cobalt and copper bearing minerals from Co-Cu oxide ores, the relationship between and the impact of physical, chemical and mineralogical properties of the materials and the dissolution behaviour of cobalt and copper bearing minerals contained in the feed materials was studied. Four Co-Cu oxide ore samples namely; high cobalt ore (HCo), high copper ore (HCu), low cobalt ore 1 (LCo1) and low cobalt ore 2 (LCo2) were characterised in terms of elemental composition, cobalt and copper species, functional groups, mineral phases, mineral abundances, mineral/ore grains size distribution, particle specific surface area, particle ore density and porosity, in order to elucidate the impact of these properties on the dissolution rate and percentage recovery of cobalt and copper in the acid generated leachate...

Magister Scientiae - MSc / It is widely believed that hydrogen will within a few tens of years become the means of storing and transporting energy. The reason is the depletion of hydrocarbons and the relatively facile production of hydrogen from various renewable sources of energy. Hydrogen can be combusted in an efficient way in a fuel cell with water as emission product. As concerns over air pollution and global warming increase, the incentive to switch to clean and efficient hydrogen economy becomes greater and the transition may occur well before hydrocarbon reserves are extinct. The overall goal of the project is to develop the knowledge base for solid-state hydrogen storage technology suitable for stationary and mobile applications. In order to accomplish this goal, the project will have a dual focus which includes the synthesis of novel nano-structured hydrogen storage materials and systems that can accurately analyze the materials. The aim of this research is to develop a novel composite hydrogen storage material with high wt% storage capacity, high intrinsic safety, appropriate thermodynamics, high mechanical strength, reversibility of the system and fast kinetics based on a well known “low temperature” intermetallic alloy (Ti/Fe) as the core. In the course of achieving this objective, the structural, thermal, chemisorptive and physisorptive attributes of this material on a nanoscale have been evaluated considering that nano-structuring is a potentially promising approach for controlling bond strength, kinetics, and sorption temperatures and pressures. By combining different materials with suitable catalytic and thermodynamic properties, a new class of hybrid hydrogen storage material has been developed. More importantly, the focus was to increase the capacity of hydrogen sorption in this material. This goal was achieved with the mechano-chemical pre-treatment of Ti/Fe alloy and surface modification with carbon nanotubes, binary palladium and magnesium metals via a layer-by-layer modification technique. The chemical and mechanical stability of hydrogen storage materials is of great importance because hydrogen storage materials must withstand repeated adsorption and desorption cycles. The layer by layer approach that was used in this project allowed the investigation of the chemical and mechanical stability of the materials as each layer was added. Through this layer by layer approach suitable nano-particles were introduced that are chemically and mechanically stable. The knowledge emanating from this investigation is expected to allow the directed design of new, higher-efficiency, recyclable hydride-based materials in pursuance of the 6.0 wt% goal set forth by the US Department of Energy. / South Africa

Please read the abstract in the section 00front of this document / Dissertation (MSc (Chemistry))--University of Pretoria, 2006. / Chemistry / unrestricted

No description available.

No description available.

Please read the abstract in the section 00front of this document. / Dissertation (MSc (Agric) Animal Nutrition)--University of Pretoria, 2006. / Animal and Wildlife Sciences / unrestricted

Although Thomas Dyke Tellefsen’s mazurkas have been considered mere imitations of Chopin’s musical idiom, his mazurkas are closely related to Norwegian folk elements. Tellefsen adopted Norwegian folkloric elements from his own country and infused Norwegian spirit into his works to create his own musical language. To trace the Norwegian folk influence, this study examines folk dance (the springar), folk instruments (the hardanger fiddle and the langeleik), and folk melodic and rhythmic motifs. As the result, this research demonstrates that Tellefsen’s mazurkas were influenced by a phrase structure of Norwegian springar dance music and the exact sound effect of folk instruments (the hardanger fiddle and the langeleik) as well as Norwegian folk rhythmic and melodic formulas which are frequently used in Norwegian folk tunes. Furthermore, the comparison between Tellefsen and Chopin’s mazurkas demonstrates that although their mazurkas seem to have a similar musical style, Tellefsen’s mazurkas include his own traditional Norwegian folk aesthetic, which present original contributions to the genre.