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This study comprises the preparation and characterisation of various novel tertiary monoand polyphosphines as well as their gold(I) complexes. The possible modes of coordination of mono-, bi- and tridentate phosphine ligands to gold(I) are summarised in Chapter One, thus serving as an introduction to coordination behaviour of the new ligands to gold(I). The synthesis and characterisation of twelve novel tertiary mono- and polyphosphines as well as the three previously known thienylphosphines, diphenyl(2-thienyl)phosphine (PS), phenyldi(2-thienyl)phosphine (PDS) and tris(2-thienyl)phosphine (PTS), are reported in Chapter Two. There are four phosphines derived from a monothiophene unit i.e., diphenyl(5-bromo-2-thienyl )phosphine (PSBr), 2,5-bis(diphenylphosphino)thiophene (PSP), phenylbis[(5-diphenylphosphino)-2-thienyl]phosphine (PDSP) and tris[(5-diphenylphosphino)- 2-thienyl]phosphine (PTSP); two from a 2,2'-bithiophene unit i.e.. diphenyl[5( 2,2'-bithienyl)]phosphine (PSS) and 5,5'-bis(diphenylphosphino )-2,2'-bithiophene (PSSP); h hi fr ') ')'. two P osp mes om a _,_ .)-,,_')"-terthiiophene um.t t..e., diipheny1[)--('_)._')'..)-,._')"-terthiieny1)]- phosphine (PSSS) and 5,5"-bis(diphenylphosphino)-2,2':5',2"-terthiophene (PSSSP); three phosphines from a 2-(2'-thienyl)pyridine unit i.e., diphenyl[5-(2'-pyridyl)-2-thienyl]phosphine (PSN), diphenyl[6-(2'-thienyl)-2-pyridyl]phosphine (PNS) and diphenyl[5-(2'{ 6'-diphenylphosphino}pyridyl)-2-thienyl]phosphine (PSNP); and one phosphine from a 2,6-bis(2'-thienyl)pyridine unit i.e., 2,6-bis[(5'-diphenylphosphino )-2'-thienyl]pyridine (PSNSP). A combination of IH, l3C and 31p NMR spectroscopy as well as mass spectrometry and microanalysis is employed to establish the structures for all the compounds, while in three cases (for the ligands PSSP. PSNP and PSNSP) the structural assignment is confirmed by X-ray crystallography. The synthetic strategies used for the preparation of the phosphine ligands vary widely from a traditional reaction between a metallated thiophene and a chlorophosphine on one hand, to a Ni-catalysed coupling reaction involving phosphine-substituted heterocycles on the other. the choice depending not only on the parent heterocyclic molecule. but also on the number of phosphorus atoms present. A new synthetic methodology leading to a potentially water-soluble diphosphine ligand is also explored. Although the target compound itself is not isolated, the preparation of its precursor, 5.5'-bis(phenylphosphino )- Xl 2,2'-bithiophene (HPSSPH), represents the first example of the synthesis of a secondary phosphine containing a thiophene moiety. In Chapter Three the reactions of the mono- and diphosphine ligands PS, PDS, PTS, PSBr, PSS, PSSS.- PSN.. PNS.- PSP.' PSSP.. PSNP.. PSSSP and PSNSP with the. gold(I) precursors (such as HAuCI4, reduced in situ with thiodiglycoL and [Au{MeCNh]SbF6) are studied. The structures of the products are elucidated by means of 'n and 31 p NMR and IR spectroscopy as well as X-ray crystallography in the case of [CIAuPSS], [CIAuPNS], [CIAu(PDS)2], [CIAu(PS)3] and [Au2(~-PSNh](SbF 6)2. Neutral complexes containing twocoordinate gold(I) are obtained for all the ligands, having general formulae [ClAuP] and [CIAu(~-PP)AuCI] , where P and PP represent a mono- and a diphosphine respectively. Isolation of neutral complexes with three-coordinate gold(I) proved more difficult and is only achieved for the complexes [CIAuP2] (P = PS, PDS, PTS and PSN) and [CIAu(~PP)] n (PP = PSP and PSSSP). A 31 p NMR study of the behaviour of complexes in solution shows the complexes with three-coordinate gold to be very labile with respect to dissociation of the third ligand. The complex [CIAu(PS)3], where gold(I) exhibits a coordination number intermediate between 3 and 4 in the solid state (as shown by the Xray crystallographic analysis), is serendipitously obtained from a reaction of [CIAu(PPh3)] and PS in a I :1 molar ratio. Both mono- and dinuclear complexes with two-coordinate gold(I) are formed when the monophosphines PSN and PNS are reacted with suitable precursors (viz. [CIAuPNS] and [Au{MeCNh]SbF6). The mononuclear complexes are of formula [Au(r{Ph]SbF6, as confirmed by IH and 3lp NMR and IR spectroscopy. In the case of the dinuclear complexes. [AU2(~-PhJX2 (P = PSN. X = SbF6: P = PNS. X = PF6), bridging is achieved via the phosphorus atom and nitrogen atom of the pyridine ring 1n both ligands. This coordination mode is consistent with the IH and 31 p NMR data for both complexes. and it is also confirmed by an X-ray structure determination of the former complex. The diphosphine ligands PSSP, PSNP and PSNSP tend to produce insoluble polymeric products when reacted with cationic gold(I) precursors. while the diphosphines PSP and PSSSP allow discrete species (e.g. [Au{r!'-PSSSP}z]PF6 and [Au2 {~-PSP hHPF6 }z ) to be isolated under similar conditions. None of the gold(I) complexes synthesised in this work displays any evidence of the thiophene ring being one way or the other coordinated to the metal, XII Chapter Three concludes with a short description of the luminescence properties of a selection of gold(I)-phosphine complexes both in solution and in the solid state. Our results confirm the previously established trend that complexes containing three-coordinate gold(I) tend to luminesce. They also show, for the first time, that a dinuclear complex with no metal-metal interaction, and where each gold atom is coordinated to one phosphorus and one nitrogen donor atom i.e., [Au2(Il-PSN)2](SbF6L exhibits luminescent properties. The results of the cytotoxic testing of a number of mono- and diphosphines (PS, PDS, PTS, PSS, PSSS, PSSP, PSSSP, PSNSP and dppe) as well as of some heterocyclic compounds and the gold(I ) complexes [CIAuPSS] and (CIAu(Il-PP)AuCI] (PP = PSSP and dppe) against two cell lines are presented in Chapter Four. The complex [CIAuPSS] shows great potency against the HepG2 (liver cancer) cell line, far exceeding that of the known cytotoxic agent, [Cl.Autu-dppej.Auf'l]. For the other cell line. A549 (lung cancer), the cytotoxicity measurements are compared for 'in the dark' and under DVA light conditions. The results show that application of DVA light generally increases the cytotoxic properties of the compounds tested. Although there appears to be a link between the phototoxic properties of a compound and its photosensitising ability (a photophysical property of thienylphosphine ligands and their gold(I ) complexes, reported at the beginning of Chapter Four) , it is not yet possible to establish a quantitative correlation between the two. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 2000

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Two experiments were conducted. The first was a control condition and used the probe signal method similar to Greenberg and Larkin (1968) to see if a filter-like attentional mechanism was acting when listeners were presented with pure tone stimuli in the presence of background noise. The second experiment also used the probe signal method of Greenberg and Larkin (1968) to investigate the extent to which listeners direct their attention to a particular fundamental frequency (f0) when detecting complex tones masked by noise. Twenty adult listeners ranging from 23 years to 54 years with a median age of 28 years participated in both experiments. Of the 20 listeners, 8 were male and 14 were female. Both experiments used a Two Interval Forced Choice (2IFC) procedure. There were two types of trials, the target signal trial and the probe signal trial. The target frequency was presented on 71% of trials, and the probe frequencies on the remaining 29%. The results of Experiment 1 were similar to those obtained in Greenberg and Larkin’s (1968) pioneering study. The 1000 Hz target tone was detected at a significantly higher proportion than probe signals differing in frequency (p < 0.05). Detection scores were observed to be higher when probe signals had a frequency close to the 1000 Hz signal compared to when they had a frequency positioned further from the 1000 Hz target tone. Experiment 2 using complex target tones with f0 of 115 Hz (part 1) and 220 Hz (part 2) revealed a similar pattern to Experiment 1. Listener’s detection scores decreased the further the f0 of probe tones were positioned from the f0 of the target tone, revealing the shape of a band-pass filter. This pattern is consistent with the presence of an auditory attentional filter in the f0 domain for complex tones

Mitochondria contain their own genetic system, encoding key subunits of the oxidative phosphorylation system. These subunits are expressed by an organelle-specific gene expression machinery. This work revealed a number of fundamental aspects of mitochondrial gene expression and provides evidence that this process is organized in a unique and organelle-specific manner which likely evolved to optimize protein synthesis and assembly in mitochondria. Most importantly, improving the experimental handling of ribosomes we could show that mitochondrial ribosomes are organized in large assemblies that we termed MIOREX complexes. Ribosomes present in these complexes organize gene expression by recruiting multiple factors required for post-transcriptional steps. In addition, we could reveal mechanisms by which ribosome-interactor complexes modulate and coordinate the expression and assembly of the respiratory chain subunits. For example we showed that the Cbp3-Cbp6 complex binds to the ribosome in proximity to the tunnel exit to coordinate synthesis and assembly of cytochrome b. This location perfectly positions Cbp3-Cbp6 for direct binding to newly synthesized cytochrome b and permits Cbp3-Cbp6 to establish a feedback loop that allows modulation of cytochrome b synthesis in response to assembly efficiency. Likewise the interaction of the membrane-anchor proteins Mba1 and Mdm38 with the tunnel exit region enables them to participate in the translation of the two intron-encoding genes COX1 and COB in addition to their role in membrane insertion.  In summary, work presented in this thesis shows that mitochondrial gene expression is a highly organized and regulated process. The concepts and technical innovations will facilitate the elucidation of many additional and important aspects and therefore contribute to the general understanding of how proteins are synthesized in mitochondria. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>

The research on pastoral counseling of persons struggling with complex trauma was undertaken with the aim of designing a practice-orientated model for pastoral counseling in order to guide such persons to emotional healing, stability and spiritual growth. An exegetical study throws light on the role of prayer and trust in God. One can entrust to God one's problems and one's supplication for help in the firm belief that He will provide a way out. An investigation into counseling perspectives in the Scriptures and in the literature on Christian counseling brought to light that pastoral counseling, which is a mandate given to believers, affords a unique opportunity for lovingly encouraging and consoling people with complex trauma. Contributions by psychiatry and psychology emphasise the phase approach. They stress security and stability, the processing of the traumatic memory and mourning, as well as a renewed commitment to new relationships. The core of the findings is that persons with complex trauma - which is an intricate syndrome relating to a spectrum of post-traumatic disturbances following intense, protracted and repeated trauma - can be guided by pastoral counseling to emotional healing, stability and spiritual growth. Specific reference is made to victims of prolonged family violence and/or physical and/or emotional and/or sexual abuse and/or protracted physical and/or emotional neglect in family context. The empirical research confirmed that the children of the Abraham Krielkinderhuis, Potchefstroom, who were subjected to these traumatic experiences in their parental homes exhibit the typical symptomatology of complex trauma. These entail emotional disturbances like anger and self-injury, disturbances of consciousness like dissociation, disturbances of self-image like stigma, guilt and shame, disturbances in the image of the perpetrator, like unrealistic expectations and finally disturbances in relationships like distrust and loss of faith. The principles and outcome of the empirical research are eventually applicable to all persons struggling with complex trauma. A practice-orientated counseling model was designed which focuses on stabilisation and security, the processing of the traumatic memory and mourning, as well as a renewed commitment to life in abundance and new relationships. In this therapeutic relationship of faith the distress narrative and the narrative of the past are central. God allows everything to turn out for the best for those who trust in Him. In Christ people are more than victors through God's will for their lives. / Thesis (Ph.D. (Pastoral))--North-West University, Potchefstroom Campus, 2006.

The main aim of this thesis is to compare actual power production from an existing wind farm with power production prediction by WindSim, which is a CFD tool based on the nonlinear flow model. The wind farm that is being worked on is located in Northern Sweden and has high orographic complexity with forested hilly terrain. There is 1 year record of met-mast wind measurements and nearly 2 years record of production data.Firstly roughness and height contours data are put as an input in order to simulate and generate wind fields over the complex terrain. In addition forest model is used to get more detailed roughness height. After generating wind fields existing turbine locations and 1-year wind speed measurement are imported.The results show that how accurate are the CFD calculations to solve turbulence in a complex terrain. Comparison between actual production data with energy production results by simulations is the main approach of this thesis work to validate the simulations.The results indicate that both WAsP and WindSim have overestimated energy production and wind speed as well. However particularly with WindSim forest module CFD calculations have more accurate results than without forest module and WAsP estimations.

Class I heavy chain (HC) must assemble with β-microglobulin (β2m) and acquire optimal peptide in order to be presented to cytotoxic T cells (CTLs). Calnexin is involved in the initial folding of class I HC and subsequent assembly with β2m. Incorporation of "empty" or suboptimally loaded class I molecules into the multimolecular loading complex is essential for them to acquire optimal peptides. The loading complex consists of several cofactors: TAP, tapasin, ERp57 and calreticulin. The precise role of calnexin and calreticulin in the regulated assembly and peptide loading and the significance of their physical interaction with other cofactors of the loading as well as preloading complex still remains unclear. Using mouse fibroblasts that lack calreticulin, I have studied the role of calreticulin in the assembly and loading of H2-K^b and H2-D^b expressed in these cells. MHC class I molecules in calreticulin-deficient cells are able to assemble with β2m normally, but their subsequent loading with optimal, stabilising peptides is defective despite their ability to interact with the TAP complex. The "empty" or suboptimally loaded class I molecules exit the ER rapidly. Reflecting the loading defect, presentation of endogenously processed antigens by class I molecules in calreticulin-deficient cells is impaired. I have used a human calnexin-deficient cell line CEM.NK^R to study assembly of class I in the absence of calnexin. The results demonstrate that contrary to current understanding, calnexin has an important role in class I HC assembly with 32- microglobulin. The role of heavy chain glycosylation in class I biogenesis is still controversial. My findings suggest asparagine (N)-linked glycosylation of human class I heavy chain at position 86 is optimal and any deviations from "normal" glycosylation results in poor loading with peptides and some defect in the assembly with β2m. Despite affecting the loading function, glycosylation did not have significant effect on presentation of a high affinity binding epitope to HLA-A*0201 specific CTLs. Finally, I show that co-operation from all domains of calreticulin is essential in order to generate a fully functional calreticulin. Interestingly, proline-rich (P) -domain of calreticulin downregulated expression of a number of cellular proteins including MHC class I HC, despite restoring the cytosolic calcium levels in calreticulindeficient cells. The effect of P-domain on class I expression was at the level of transcription.

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