In vitro studies of drug permeability are traditionally carried out using cultured monolayers of epithelial cell lines grown on semi permeable membranes. Caco-2 cells, which are colon-derived, spontaneously form polarised cell layers when cultured in vitro which are akin to an epithelium of enterocyte-like cells. The Caco-2 model has been developed as a powerful in vitro tool in the early assessment of human drug permeability and is even approved by regulatory agencies for biowaver applications (i.e. in vitro tests in lieu of in vivo animal experiments). As Caco-2 cells are derived from colon tissue they represent a more formidable barrier to drug absorption than the upper regions of the intestine which is where the majority of oral drugs permeate into the body. Whilst the Caco-2 model, alongside other in vitro methods, has provided a significant means to understand the mechanics of drug permeability. Many researchers have sought to improve upon the existing unicellular model; it is hoped that this will result in a more relevant and predictive model for researchers to test new drugs but also to dissect cellular cross talk and to probe cell-matrix interactions. Myofibroblasts are a niche cell type located subjacent to epithelial tissues which regulate the integrity, growth and differentiation of the overlying epithelium. In this study the co-culture of human epithelial cell lines with a myofibroblast cell line, CCD-18co, were investigated to study how myofibroblasts influence the barrier integrity of epithelia in vivo. Additionally, nanofibre scaffolds produced by electrospinning were explored as 3-dimensional and topographically relevant cell scaffolds to support the growth of intestinal cells in vitro. In a traditional transwell format, cultured epithelial lines Caco-2 (intestinal), HT-29 (intestinal) and Calu-3 (airway) in co-cultures with CCD-18co revealed cell-line specific response with respect to the modulation of barrier integrity. The mechanism of the modulation was confirmed to be mediated through paracrine signalling by using myofibroblast conditioned media. Fibre scaffolds which mimic the fibrillar nature of the extra cellular matrix and basement membrane were produced by electrospinning using the polymer, poly (ethylene terephthalate). Nanofibre scaffolds were characterised and further optimised for cell culture with surface coating with collagen to achieve adequate cell attachment and confluence. Work was also conducted to incorporate villi architectures into the fibre scaffolds; the potential of this ambition was investigated by using models produced by rapid prototyping. These models, which demonstrated good fidelity with the actual villi dimensions found in vivo, were used during the electrospinning process to shape the polymer scaffolds towards the geometry found in intestinal tissue. A number of molecular tracers and model drug compounds were used to evaluate the permeability profiles of Caco-2 monocultures, Caco-2/CCD-18co co-cultures cultured on the two different culture substrates in addition to the assessment of resected porcine intestinal tissue sections. Caco-2 cells and Caco-2/CCD-18co co-cultures grown on nanofibre substrates were found to have lower electrical resistance and higher permeability properties than their transwell equivalents. Caco-2/CCD-18co co-cultures on conventional transwell inserts demonstrated a permeability profile closer to the resected porcine tissue and reported human tissue values than the conventional Caco-2 model whilst maintaining p-glycoprotein assay sensitivity. This work forms a solid foundation for further research into the role of myofibroblasts in epithelial cell function and in the development of more predictive in vitro cell models for widespread scientific research.

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The use of bioimpedance techniques for malignancy identification is considered novel, with challenges existing that need to be overcome. In this thesis, such bioimpedance approaches have been developed for identifying malignancies through a systematic study, ranging from the investigation of the technical challenges affecting an imaging based breast cancer detection system, to the study of electrical properties of tissue and cells. Hence, this work provides proof-of-concept for cancer diagnosis based on the electrical signatures that differentiate malignancies from normal tissue, utilising bioimpedance analysis techniques. Further, this work will contribute to the understanding of correlations between electrical properties and biological functions, which will help to explore bioimpedance techniques for wider medical and bioscience applications. Furthermore, this research will also be conducive to investigations of novel devices for cancer diagnosis in clinic. The Ph. D work was carried out in two threads. In the first thread, technical challenges of using Electrical Impedance Mammography (EIM), an imaging modality developed based on bioimpedance technique for breast cancer diagnosis, were studied on 1) effectively reducing measurement errors from electrode contact interfaces, and 2) validating systems by using novel simulation phantoms. In the second thread, bioimpedance spectroscopy (BIS) of tissues and cells was investigated to 1) reveal their electrical properties, 2) identify malignant changes, and 3) establish correlations of electrical properties with biological function changes. By carrying studies in these two threads, bioimpedance was fully investigated for its applications on cancer detection and diagnosis. This work has made significant contributions to the field of study. It comprises the first systematic study on bioimpedance for cancer identification at the tissue and cellular levels. This work has also been pioneering in linking the electrical properties of malignant tissues and cells to the relevant biological changes brought on by the aforementioned malignancies.

Mobile augmented reality has become an influential tool for digital content representation and visualization of media content in terms of enhancing users' experience and improving the adaptability and usability of typical augmented reality applications, such as in e-commerce shopping, virtual museum, or digital heritage scenarios. This research proposes a new Service Oriented Mobile AR Architecture called SOMARA, which includes a novel mobile AR client application. SOMARA takes advantage the ability to integrate third party content through service orientation. The SOMARA architecture enhances traditional standalone mobile AR applications with embedded media content by uniquely integrating a web service framework into an augmented reality client application to create more efficient and flexible mobile augmented reality applications that efficiently supports novel media content acquisition and visualization through appropriate access parameters. The proposed architecture requires access to media content through specific media content service providers, e.g. a museum commissioning an augmented reality based museum interactive — predetermined media content, or any third party with their own service APIs, e.g. the Victoria and Albert Museum API — related external media content. This approach allows relevant third party media content to be ‘mashed' via their public API with museums' augmented reality interactive's ‘embedded' media content in the SOMARA mobile AR client. In this way novel mobile AR interactive applications, such as a museum augmented reality interactive, can be created based on particular museum environment scenarios that integrate a museum visitor's experience with the interactive's cultural objects. Such experiences based on a SOMARA type museum augmented reality interactive can also be saved allowing visitors to take home their museum experience. SOMARA thus allows museum interactive experiences based on visualization of museums and third party media content physically located in the museum to be migrated to the visitor's home environment for further study, enjoyment and understanding. This unique feature, ability to effectively replay the experience at home, of the proposed system utilizes service-orientation to integrate third party media content, which is currently deficient from commercial augmented reality solutions.

This research examines the social use of the Internet at the level of specified online users in conservative Arab societies, who are called in this thesis online lead users. These specified lead users are the ones who are influential in shaping the innovation processes due to their leading role of practice in finding solutions to their needs and problems they have experienced before the emergence of online social networks such as the lack of public sphere and independent civic organizations etc., which led them to utilize the Internet as their new public space to pursue their goals through their online initiatives and collective actions to apply the social change they seek for their societies under the existence of society social norms and censorship. The research has been carried out as mixed-method study, the gathered data done through means of quantitative and qualitative methods, and the chosen country to conduct the research were Saudi Arabia. A survey questionnaire link were distributed among the targeted online lead users in the country under study, and the author chose three cases form the country under study for the qualitative part. The research sought to examine to what extent society social norms and censorship influence online lead user's expression and behaviours, and their effect on the formulation of their online activities and collective actions, and analyzing the characteristics of online lead user's. The significance of this study lies in the fact that it contribute to the gap in the literature on the use of Internet in conservative Arab societies by providing insight into the roles that social norms play in influencing online behaviour, particularly in communities that are seeking to discuss social issues or mobilize collective action, and analysing online lead users characteristic to distinguish between conservative and cosmopolitan ones using the Right-Wing authoritarian measurement.

As in other less developed countries in the region and elsewhere, cancers are becoming a major cause of morbidity and mortality in Jordan. Globally, colorectal cancer (CRC) is the second most common cancer in women and the third most common cancer in men. In Jordan, CRC is the second most common cancer in women and the most common in men. There is little known about survival from CRC in Jordan and few survival studies have been conducted in comparable Eastern Mediterranean countries. As the first study of its type in Jordan, this thesis aimed at estimating CRC survival among Jordanian patients and comparing them with survival estimates among other populations. The thesis explored the relationship between CRC and socio-demographic characteristics, clinical manifestations, treatment, diabetes mellitus – for which the prevalence in Jordan is very high - and treatment sites. The study augmented existing Jordan Cancer Registry data by gathering additional case mix information and completing missing fields. CRC was classified according to international classification of oncology (ICD-O third edition in addition to the International Classification of Diseases, ICD-10) as C18.0-C20.9. The vital status of the patients was ascertained from Civil Registration Bureau based on use of the unique National Identification number of the patients with follow-up to 31 December, 2010. The survival duration of each case was determined as the time difference (in days) between the date of incidence (index date) and the date of death, date of loss to follow-up or the closing date for follow-up (31 December, 2010). Observed and relative CRC survival rates were calculated among a study population of 1,896 Jordanian colorectal patients aged 15 to 99 years of age, diagnosed with first invasive primary CRC from January 2003 to December 2007. The Kaplan-Meier method was used to determine the observed survival probability over time. The logrank test was used to estimate whether the difference in survival estimates was statistically significant between the groups. The complete approach of estimation of observed survival probability was used. Cox proportional hazard regression was used to assess the effect of each variable after simultaneously controlling the effects of potential confounders. With half of the sample aged 60 years and above, males were predominant (55.5 percent) with the majority of the sample (75.4 percent) residing in the central part of Jordan. The vast majority of the cases (63.5 percent) were diagnosed with colon cancer, with regional metastasis present in 58.9 percent. No significant difference was found in the distribution of colon and rectum cancer by sex. Adenocarcinoma was the most commonly found tumor (84.4 percent) compared to mucinous tumors which was found in 7.8 percent of the patients. In addition, 62.7 percent of the cases were classified as moderate and 14.9 percent as poor. The percentages of rectum cancer patients with moderate and poor/anaplastic types of cancer were higher than in colon cancer patients. The majority of patients (77.9 percent) underwent surgery, which was mostly elective (82.0 percent). A significantly higher occurrence of these elective surgeries was found among rectum cancer (87.7 percent) than colon cancer patients (78.7 percent). Curative treatment was found to be a more common form of treatment for colorectal cancer patients (76.5 percent) than palliative (23.5 percent). Of those undergoing surgery, 4.8 percent has died within 30-days of resection, with a significantly lower mortality among patients aged ≤ 65 years (2.9 percent) than the over 65 years age group (7.1 percent). Thirty days postoperative mortality was significantly higher among colon cancer patients (5.3 percent), patients with more advanced tumours and those who underwent emergency operations. Results of this study revealed that the incidence of CRC in the Jordanian population to be low compared to developed countries. However, this low incidence is similar to CRC incidence rates in other countries in the region. During the 5-year study period, the overall crude colorectal cancer incidence rate for males was 5.6 per 100,000 population, and 5.1 per 100,000 populations in females. The overall Age Standardized colorectal incidence rate (ASR) among males was 15.5 per 100,000 populations compared to 12.5 per 100,000 populations among females. For colon cancer, the crude incidence rate was 5.4 per 100,000 populations in males and 4.1 per 100 000 populations in females, while ASR for males was 11.1 and 8.4 for females. Alternatively, the crude incidence rate for rectum cancer was 3.0 per 100,000 population for males and 2.4 per 100,000 population for females, and the respective ASR incidence rates was 6.1 per 100,000 males and 4.9 per 100,000 females. Unexpectedly, results showed a high percentage (13.8 percent) of CRC patients among the young age groups (i.e. less than 40 years of age) with insignificant differences between the sexes. The age specific incidence rates were found to increase with age. The study revealed that 5-year observed and relative survival probabilities for colorectal cancer to be 57.7 and 61.3 percent respectively, with higher probability for colon cancer. These results showed good survival estimates of colorectal cancer compared to developed countries as well as the most developed countries in the region and across the Asian continent. The slightly higher observed colorectal survival rates among females were found to be insignificantly different than those for males. Patients aged 45 through 59 years had the highest survival estimates among all age groups, and the 75 years and above age group the lowest. The highest survival estimates were found among patients living in the central parts of Jordan, and the poorest was significantly noted in the south. Moreover, the observed and relative survival estimates were consistently highest during Year 1 and lowest during Year 5. Mucinous and serous tumors showed the poorest survival rates among the colorectal cancer, with higher 5-year relative survival rates among the mucinous and serous type of colon (52.4 percent) compared to rectum cancer (42.8 percent). With more than half of the colon patients (57.2 percent) and rectal patients (62 percent) having a regional spread; a higher proportion of colon cancers (24.1 percent) were found to have distant metastasis, than rectum cancer patients (20.5) and an equally low (11 percent) had localized CRC at diagnosis. Results also showed that observed and relative survival rates from localized and regional colon cancer were better than survival from rectum cancer in the same stages at 1, 3 and 5-years of diagnosis. Results also indicated that observed survival became poorer with increasing age for both localized and regional tumours. This observation was applicable for both males and females. In recognizing appropriate surgery as the most important aspect of colorectal cancer treatment, the observed survival probability for colorectal cancer patients who underwent surgery was found significantly higher than that for patients who did not undergo surgery. This scenario was similarly observed for both colon and rectum. Conversely, the overall relative survival rates for patients who underwent surgery declined from 96.2 percent to 62.6 percent between the first and fifth year and from 86.5 percent to 23.5 percent for patients who did not undergo surgery. In addition, no significant difference was found between colorectal survival estimates for patients who underwent elective surgery and those who underwent emergency surgery. This was held true for both colon and rectum cancer.

In the past 15 years the field of cancer metabolism has burst providing vast quantities of information regarding the metabolic adaptations found in cancer cells and offering promising hints for the development of therapies that target metabolic features of cancer cells. By making use of the powerful combination of metabolomics and 13C-labelled metabolite tracing we have contributed to the field by identifying a mitochondrial enzymatic cascade crucial for oncogene-induced senescence (OIS), which is a tumour suppressive mechanism important in melanoma, linking in this way OIS to the regulation of metabolism. Furthermore, we have identified the dependency on glutamine metabolism as an important adaptation occurring concomitantly with the acquisition of resistance to vemurafenib (BRAF inhibitor) in melanoma, which opens the possibility to combine therapies targeting glutamine metabolism with BRAF inhibitors, in order to overcome or avoid the onset of resistance in melanoma. Using the same strategy we have discovered an important mechanism of interregulation between glycolysis and amino acid metabolism, identifying the glucose-derived amino acid serine as an activator of the main isoform of pyruvate kinase present in cancer cells, PKM2. In addition, we provide new insights into the mechanism of allosteric regulation of this complex protein and a better understanding of the way it regulates central carbon metabolism. In summary, our results open new possibilities for the development of cancer therapies that manipulate metabolic adaptations found in cancer cells in order to kill them specifically or halt their growth.

Human cancer stem cells are proposed to play a critical role in tumour initiation and maintenance by their exclusive ability to regenerate the tumour. Thus cancer stem cells share many of the properties of normal stem cell including self-renewal and ability to give rise to progeny which undergo tissue-specific differentiation. Thus we hypothesised that by determining the normal patterns of tissue differentiation within cancer we could identify tumour type specific factors that promote differentiation, for therapeutic development. Therefore the aim of this study is to define patterns of human hair follicle differentiation in human basal cell carcinoma (BCC) in order to elucidate potential drug-able targets that can promote tumour specific differentiation. To test this hypothesis we analysed 20 different hair follicle specific differentiation markers, which define distinct layers within the normal adult hair, in six different human BCC samples using RT-PCR with normal hair follicle tissue as control. For the 12 specific keratin genes expressed in the BCC, we analysed expression by immunofluorescence on 20 different BCC samples, using hair follicle samples as positive controls. Our findings suggest that human BCC demonstrates both inward and upward differentiation patterns similar to the hair follicle, with expression of: outer root sheath (K5,14,16,and k17), companion layer (K75), inner root sheath (K26,27,28,71,72,and k74), and cuticle (K32,35,82,and k85); but not hair shaft (K31) markers. Consistent with these findings we observed the mutually exclusive relationship between expression of the early differentiation marker K19 and cell proliferation in the hair follicle and BCC. Similarly, expression of the outer root sheath keratins coincided with nuclear translocation of both GLI1 and NFIL-6, suggesting that BCC also share normal hair follicle tissue regulatory pathways. To further test the hypothesis that normal tissue factors observed in the hair follicle regulate BCC differentiation we have developed an in vitro BCC assay. Using this tissue culture model we hypothesised that BCC’s are stuck in the telogen part of the hair follicle cycle, resulting from autocrine expression of bone morphogenic proteins 2 and 4. Inhibition of BMP signalling by addition of noggin as well as addition of TGF-β to BCC colonies in tissue culture led to further induction of inner root sheath, cuticle and medulla keratins. In summary we have shown that BCC exhibit hair follicle differentiation, which is similarly regulated, but is stuck in telogen arrest and can be rescued by addition of noggin and TGF- β2.