This research report is a techno-economic analysis of the nuclear project management capacity in South Africa. It will focus on the project development phases of the nuclear expansion programme. The author has nuclear engineering training background and also currently involved in the Eskom new build programme (Medupi & Kusile) and the coal refurbishment projects. The following thinking philosophy is used to structure this research report: * Project management practise for nuclear projects globally * Project management practise for major Eskom projects in South Africa * The differences between South Africa and international project management practises * Guideline for project management in the nuclear environment for possible implementation of the nuclear expansion programme. The project life cycle has different phases, namely, project setup and planning phase, project design and engineering phase, and project execution phase. The first two phases were discussed and analyzed in detail. The project execution phase was also discussed, however, due to the limited time, the execution phase will not be analyzed in detail. Further research is recommended on the execution phase. At the end of this research report, a guideline for nuclear project management is developed and associated with some recommendations. This guideline can certainly assist Eskom or other potential NPP developer to understand all the critical aspects in a nuclear expansion programme. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014

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Endothelial Progenitor Cells (EPCs) are thought to participate in the healing of injured vascular endothelium by incorporating into the defect sites to mediate endothelial recovery. Recently, osteopontin (OPN) was shown to be fundamental in accelerating estrogen-dependent healing of injured blood vessels. Here, we are investigating the effect OPN has on EPC behavior. Late outgrowth human EPCs (LEPCs) were derived from circulating monocytes isolated by leukophoresis, and grown in culture until passage six. L-EPCs were then assayed for adhesion, spreading, chemotaxis, and haptotaxis, as well as resistance to detachment by flow electric cellsubstrate impedance sensing (ECIS). The results of standard and ECIS methods showed both dose and time dependent responses in cell adhesion and spreading. In addition, OPN promoted haptotactic migration of EPCs in Boyden chamber assays. LEPCs seeded onto 10μM OPN substrates and exposed to laminar flow had grater survival and higher resistance to detachment than OPN/static and flow only conditions. CD44 and !1 integrins were only responsible for approximately 50% of LEPCs adhesion to OPN compared to the unblocked condition. Western blots showed that Rho GTPases were activated in L-EPCs seeded on OPN. However, this activation could not be completely blocked by either CD44 or !1 integrin antagonists. These data confirm the direct effects of OPN on EPCs adhesion, and suggest that OPN works by mediating cell adhesion during vascular injury.

The 3GPP Long Term Evolution (LTE) is considered as a dominant future cellular wireless technology in terms of performance and user experience. With technological advancement of the wireless networks, dependencies and business impact of the mobile network services have increased phenomenally. It is, therefore, crucial to address the issues regarding network infrastructure or service failure. In this thesis, a self-healing solution is presented for the LTE Evolved Packet Core (EPC) with a view to maintaining service continuity in the event of core network elements - the MME and S-GW failures. The core network element failures have significant impact on a larger number of subscribers in comparison to the access network element failures. In the proposed self-healing scheme, the restoration mechanisms and associate failover recovery procedures with regards to service survivability are described in details from the LTE network and protocol perspective. This thesis studies two different self-healing approaches - the centralized active-backup and distributed active-active and conducts simulation for each approach in various failure scenarios. The performances of each of these scenarios are evaluated in terms of service restoration time, throughput, EPS (Evolved Packet System) bearer delay etc. The results show that the proposed self-healing system can ensure service continuity at a certain level if resources are properly provisioned. And in terms of restoration delay, in general, the active-backup configuration performs better than the active-active configuration. The thesis presents analytical and simulation methods to estimate signaling message overhead at the LTE EPC that arises due to the recovery process. It also analyzes the bandwidth requirements of the signaling traffic that is incurred by the other operational procedures of the self-healing scheme and their ramification to the LTE core network. / UOIT

The objective of this project was to evaluate the effects of local endothelial progenitor cell (EPC) therapy on bone regeneration in a segmental defect in the rat femur. Animals from the EPC-treated (N=28) and control (N=28) groups were sacrificed at 1, 2, 3, and 10 weeks post-operatively. Bone healing was evaluated with radiographic, histological, and micro computed tomography (micro-CT) scans. Radiographically; mean scores of the EPC group at 1, 2, and 3 weeks were significantly higher compared to control group. At 10 weeks, all the animals in the EPC group had complete union (7/7), but in the control group none achieved union (0/7). Histologically, specimens from EPC-treated animals had abundant new bone formation compared to controls. Micro-CT assessment showed significantly improved parameters of bone healing for the EPC group compared to control group. In conclusion, local EPC therapy significantly enhanced bone regeneration in a segmental bone defect in rat femur.

The objective of this project was to evaluate the effects of local endothelial progenitor cell (EPC) therapy on bone regeneration in a segmental defect in the rat femur. Animals from the EPC-treated (N=28) and control (N=28) groups were sacrificed at 1, 2, 3, and 10 weeks post-operatively. Bone healing was evaluated with radiographic, histological, and micro computed tomography (micro-CT) scans. Radiographically; mean scores of the EPC group at 1, 2, and 3 weeks were significantly higher compared to control group. At 10 weeks, all the animals in the EPC group had complete union (7/7), but in the control group none achieved union (0/7). Histologically, specimens from EPC-treated animals had abundant new bone formation compared to controls. Micro-CT assessment showed significantly improved parameters of bone healing for the EPC group compared to control group. In conclusion, local EPC therapy significantly enhanced bone regeneration in a segmental bone defect in rat femur.

Endothelial Progenitor Cells (EPCs) are thought to participate in the healing of injured vascular endothelium by incorporating into the defect sites to mediate endothelial recovery. Recently, osteopontin (OPN) was shown to be fundamental in accelerating estrogen-dependent healing of injured blood vessels. Here, we are investigating the effect OPN has on EPC behavior. Late outgrowth human EPCs (LEPCs) were derived from circulating monocytes isolated by leukophoresis, and grown in culture until passage six. L-EPCs were then assayed for adhesion, spreading, chemotaxis, and haptotaxis, as well as resistance to detachment by flow electric cellsubstrate impedance sensing (ECIS). The results of standard and ECIS methods showed both dose and time dependent responses in cell adhesion and spreading. In addition, OPN promoted haptotactic migration of EPCs in Boyden chamber assays. LEPCs seeded onto 10μM OPN substrates and exposed to laminar flow had grater survival and higher resistance to detachment than OPN/static and flow only conditions. CD44 and !1 integrins were only responsible for approximately 50% of LEPCs adhesion to OPN compared to the unblocked condition. Western blots showed that Rho GTPases were activated in L-EPCs seeded on OPN. However, this activation could not be completely blocked by either CD44 or !1 integrin antagonists. These data confirm the direct effects of OPN on EPCs adhesion, and suggest that OPN works by mediating cell adhesion during vascular injury.

Endothelial Progenitor Cells (EPCs) were first identified from human blood samples as a population of circulating mononuclear cells capable of displaying a mature endothelial cell phenotype in culture. Subsequent studies have established that EPCs arise from the bone marrow (BM) and incorporate into the endothelium at sites of blood vessel growth, suggesting a potential role for these cells in neovascularization. Furthermore, a decline in EPC count has been correlated to multiple vascular pathologies, indicating that EPC number could serve as a biomarker of cardiovascular disease. Unfortunately, due to the variability in techniques used for EPC isolation and identification, considerable heterogeneity exists within the population of cells commonly defined as EPCs. In order for the clinical potential of EPCs to be fully realized, thorough characterization of the BM-derived cell populations involved in neovascularization is required. The objective of our study was to determine the functional significance of circulating EPCs in postnatal vascular growth and repair. Two separate strategies were employed to achieve this objective. In the first, we attempted to generate a novel mouse model where the pool of bone marrow-derived endothelial precursors was drastically reduced or eliminated. Our overall approach was to deliver a "suicide" gene, under control of an endothelial cell-specific promoter, to bone marrow cells for use in bone marrow transplantation (BMT) experiments. Mice receiving BMTs would therefore lack the ability to deliver viable BM-derived EPCs to sites of neovascularization. Our central hypothesis for this study was that a reduction in EPC viability would hinder endogenous vascular repair mechanisms, thereby exacerbating cardiovascular disease. In the second strategy, we attempted to identify novel progenitor cell populations based on the transcriptional regulation of pro-angiogenic genes. Our overall approach was to transduce BM with a retrovirus containing a fluorescent reporter gene under control of pro-angiogenic promoters for use in transplantation experiments. Our central hypothesis for this study was that unique populations of BM-derived cells could be identified by expression of the fluorescent reporter gene directed by the Vascular Endothelial Growth Factor (VEGF), endothelial Nitric Oxide Synthase (eNOS) and Vascular Endothelial (VE) Cadherin promoters. The BMT strategy utilized to address our first hypothesis was unsuccessful due to the use of a truncated form of the pro-apoptotic Bax as our suicide gene target. A plasmid encoding GFP fused to the truncated Bax fragment (ΔN-Bax, consisting of amino acids 112-192 of the full length protein) was used in transfection experiments to assess ΔN-Bax function. The GFP:ΔN-Bax fusion protein formed distinct extranuclear aggregates (presumably due to mitochondrial translocation) but did not induce apoptosis in transfected cells. The ΔN-Bax fragment also did not induce cell death when targeted to endothelial cells with retoviral-mediated gene delivery or in a transgenic mouse setting. To address our second hypothesis, we generated retroviral vectors containing the fluorescent tdTomato reporter under control of the VEGF, eNOS and VE Cadherin promoters. Significant fluorescence was detected in cultured endothelial cells and ex vivo-expanded BM cells. Following transplantation of transduced BM cells into lethally irradiated recipient mice, we were able to identify circulating populations of tdTomato-positive cells using flow cytometry. With these results we have identified novel subpopulations of circulating BM-derived cells which may play a significant role in post-natal neovascularization in mice. Therefore, results acquired from these studies could lead to improved cell therapy techniques for treatment of vascular disease.

Im Rahmen der vorliegenden Dissertation wurde mithilfe eines 4 stündigen Radmarathons die zeitabhängige Freisetzung von zirkulierenden Vorläuferzellen untersucht. Hierzu wurde den 17 gesunden, gut trainierten Probanden während der Prozedur zu festgelegten Zeitpunkten Blut aus einer Venenverweilkanüle entnommen. Daraus wurden mittels Dichtegradient die mononuklearen Zellen isoliert und im Anschluss mittels Durchflusszytometrie die Konzentration der zirkulierenden Progenitorzellen quantifiziert. Es ließ sich ein signifikanter zeitversetzter Anstieg der Konzentration hämatopoietischer Progenitorzellen (CD34pos und CD133pos) wie auch endothelialer Progenitorzellen (CD34/KDRpos und CD133/KDRpos) ermitteln. Die maximale Konzentrationsänderung wurde nach 210 Minuten erreicht. Als Freisetzungsmediatoren wurden in dieser Arbeit die Konzentration von VEGF und IL-6 bestimmt. Auch hier stellte sich ein signifikanter Anstieg der Spiegel dar. Die Konzentrationsänderungen der einzelnen Zellpopulationen waren spätestens 24 Stunden nach Beendigung des Radmarathons nicht mehr nachweisbar. Des Weiteren ging die Arbeit der Frage nach, wie sich die Konzentration von Mikropartkel und endothelialer Mikropartikel als Marker für einen Endothelzellschaden auswirkt. Ein Anstieg der Konzentration reifer (CD146pos) Endothelzellen wurde verzeichnet. Ausgangspunkt dieser Arbeit war die sehr beschränkte und kontroverse Datenlage bezüglich der Konzentrationen von Progenitorzellen freigesetzt durch sportliche Aktivität.

This research report is a techno-economic analysis of the nuclear project management capacity in South Africa. It will focus on the project development phases of the nuclear expansion programme. The author has nuclear engineering training background and also currently involved in the Eskom new build programme (Medupi & Kusile) and the coal refurbishment projects. The following thinking philosophy is used to structure this research report: * Project management practise for nuclear projects globally * Project management practise for major Eskom projects in South Africa * The differences between South Africa and international project management practises * Guideline for project management in the nuclear environment for possible implementation of the nuclear expansion programme. The project life cycle has different phases, namely, project setup and planning phase, project design and engineering phase, and project execution phase. The first two phases were discussed and analyzed in detail. The project execution phase was also discussed, however, due to the limited time, the execution phase will not be analyzed in detail. Further research is recommended on the execution phase. At the end of this research report, a guideline for nuclear project management is developed and associated with some recommendations. This guideline can certainly assist Eskom or other potential NPP developer to understand all the critical aspects in a nuclear expansion programme. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014