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Some chemical processes are potentially explosive and make use of metallic vessels. Monitoring such kinds of processes using the Three-Dimensional Electrical Impedance Tomography (3D EIT) method is of interest to Industry. The work focuses on the challenge of producing a three-dimensional forward solver for 3D EIT of domains with conducting boundaries. This was limited to two dimensions prior to the start of this project. The problems and shortcomings of 3D EIT in industrial vessels that have a metallic structure are explored with an emphasis on intrinsic safety. This has been evaluated by addressing the project "PROCEss tomography for MONintoring industrial pressure filters (PROCEMON)". It is suggested here that, the ElT software and hardware, presently used in PROCEMON, requires further investigation.

The role of the tumor suppressors p53 and p16 genes in the cellular response to Ultraviolet light. SUMMARY Proliferating cells respond to DNA damage by concomitantly arresting cellular growth at checkpointsa nd activating DNA repair processesC. ell cycle arrestsa re mediated,i n part, by the inhibition of cyclin-dependent kinases (CDKs), whose function is required for cell cycle progression. p53, p21WAF' and p16`NK4aa re the products of tumor suppressor genes that play important roles during the cellular response to genotoxic stresses. p53 and p16 coding genes have been found mutated or transcriptionally silenced in different cancer types both sporadic and familial. Indeed, p16 has been found to be linked to familial melanoma, whose etiology is related to sun-light induced DNA damage. It is hence important to ascertain whether p53 and p16 are involved in the cellular response to UV damage. In this report I present evidence that p53 is not involved in UV-induced cellular growth arrest in late G1 phase. This has been demonstrated in HeLa cells synchronized at the G1/S border by aphidicolin, followed by UV exposure. Interestingly, the length of this p53-independent G1 arrest has been shown to be UV dose-dependent. Similar results were also obtained with other p53-deficient cell lines, including the human promyelocytic leukemia HL-60 and mouse p53 knock-out cells. As expected, all of these cell lines were defective in v-ray-induced cell growth arrest at late G1Using different assays I also show here that p16-compromised U20S osteosarcoma cells are deficient in the removal of UV damage, as compared to their isogenic derivatives EH1 and EH2 counterparts that express p16. This deficiency is associated with a high level of UV-induced apoptosis, which is significantly reduced in the p16-expressing EH I, EH2 and p16+/+ mouse embryonic fibroblast (MEF) cells, indicating that p16 protects cells from undergoing apoptosis in response to UV light. Importantly, this reduction in UV-mediated apoptosis was associated with down-regulation of the pro-apoptotic Bax protein, with no effect on Bcl-2 expression, suggesting that this anti-apoptotic role of p16 is mediated via the intrinsic p53-dependent mitochondrial pathway. On the other hand, p16 sensitized cells to cisplatin-mediated apoptosis through Bcl-2 decline. Furthermore, I show that p16 is involved in UV-related G1 checkpoint and controls the expression and UV-dependent activation of another CDK inhibitor, p21wAFI. Importantly, this relationship between p16 and p21 exists also in MEFs, suggesting that it is not cell type- or species-dependent. These results indicate that, in addition to its role in cell cycle control and senescence, p16 also plays an important role in the cellular response to UV damage, possibly by inhibiting apoptosis and facilitating cell cycle arrest and photolesion removal. The data presented here provide further insights into the role of p53 and p16, as tumor suppressors, in carcinogenesis and have potential implications for future therapy strategies

Poly-3-hydroxybutyrate (PHB) conduits are an alternative to nerve autografting and support regeneration across long nerve gaps, although to suboptimal levels. The aim of this study was to improve these results by combining PHB with glial growth factor (GGF), enhancing nerve regeneration by contact guidance and an improved trophic microenvironment. Two and 4cm gaps in the rabbit common peroneal nerve were bridged using PHB-GGF conduits. The rate and quantity of axonal and Schwann cell (SC) regeneration were assessed by quantitative immunohistochemistry at 21, 42 and 63 days, and compared to empty and alginate filled conduits. Addition of GGF improved axonal and SC regeneration, which was sustained up to 63 days independent of gap length. The distance and quantity of axonal regeneration were increased by up to 53% and 4317% respectively. At 120 days axonal and SC regeneration within the PHB-GGF grafts remained superior to the controls resulting in enhanced motor organ reinnervation, as was demonstrated by an improved recovery of muscle mass compared to the controls. In both the short and long term studies the alginate filled conduits resulted in regeneration inferior to both the GGF and empty tubes. As a result alginate fibres were assessed in vitro and in vivo as an alternative to alginate hydrogel with a potential to deliver GGF. However, regeneration in vivo in alginate fibre filled conduits was inferior to conduits filled with alginate hydrogel. Polyhydroxyalkatone (PHA) was also evaluated as a conduit material, as GGF linkage and release from its walls is a feasible option. Four different PHA configurations were used to bridge a 1cm rat sciatic nerve gap. All 4 PHA configurations, accelerated axonal regeneration rate to 1mm/day versus 0.7mm/day with PHB conduits and resulted in a quantity of axonal regeneration superior to that seen in the autograft repairs. In conclusion, GGF improves axonal and SC regeneration across short and long gaps through PHB conduits, but alginate hydrogel appears to limit the trophic effect of GGF. Alginate fibres provide no improvement, however alginate's limitations may be overcome and regeneration further improved by using PHA as a bioconstruct releasing GGF into the conduit microenvironment.

In a typical content-based video retrieval system, the user submits a query and will then expect the system to locate all similar data in the corresponding video database. Content-based means representing the image content by means of low level visual features that are extracted through image processing techniques. The low level features include colour distributions, textures, shape and motion, in the case of video. In this thesis, a novel content-based video retrieval system using shape features is proposed. To provide indices, first all the shots in a video sequence are extracted. Then corners of all frames in each video shot are detected applying proposed curvature scale space corner detector using different scale of smoothing. As a user interface, a proposed fast active contour model is used to specify one object of interest as a query in one of the frames of each video shot. Afterwards, closest corners of query object to the final snake in this frame are extracted and tracked forward and backward through the whole of that shot using proposed multiple-match tracker. This tracker, which does not make any important assumptions or use any motion models, can retrieve the query in any video sequence even when there is non-smooth and unconstrained motion. By tracking the corners of query object forward and backward, the positions of similar objects in each video frame are determined. Two methods are considered for demonstrating the query and its similar objects to the user. Experiments have been carried out on a wide range of real video databases. All the results confirm that the proposed method which exploits frame corners is more efficient and more generally applicable.

Introduction Neonatal mortality and morbidity from premature birth are still a major concern despite significant advances in perinatal medicine. Objective of the study The primary aim of the study was to establish the feasibility of accurately identifying a cohort of vvomen at increased risk of preterm birth using a modified risk assessment score and fetal fibronectin testing in order to undertake a pilot randomised placebo-controlled trial of nifedipine as a tocolytic. Methodology A population of pregnant women was screened prospectively between 24 and 34 weeks of gestation using a modified risk assessment system. Women identified as high-risk for preterm birth were then tested with fetal fibronectin. Those testing positive were randomised to either nifedipine or placebo. The study at this point was randomised, placebo-controlled and double-blind. Measures of outcome were compared for babies of trial vvomen with high-risk women who withheld consent. Main outcome measures Delivery before 34 weeks, neonatal death, admission to the Special Care Baby Unit (SCBU), chronic lung disease and major cerebral abnormality on ultrasound scan constituted the main measures of outcome. Results Five hundred and thirty four vvomen were identified as high-risk for preterm birth. One hundred and forty two women agreed to participate in the study. Forty nine women delivered before 37 weeks' gestation. The system was sensitive in predicting preterm birth before 34 weeks of gestation and within one week of testing for fetal fibronectin in symptomatic women. Babies of non-consenting mothers fared better overall than babies of the trial women. Conclusion Risk factor scoring and fetal fibronectin testing are useful screening tools that can predict preterm delivery. This sysytem can be clinically useful in the management of preterm labour or women at increased risk for preterm birth. There was no impact on the neonatal mortality or morbidity.