SACM - United Kingdom
Permanent URI for this collectionhttps://drepo.sdl.edu.sa/handle/20.500.14154/9667
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Item Restricted The Impact of Waiving Confirmatory Efficacy Studies on Biosimilar Development Costs and Timelines: A Comparative Analysis of Adalimumab Biosimilars(Saudi Digital Library, 2024) Daniah, Fatani; Zloh, MireThe emergence of biosimilars has transformed healthcare by offering cost-effective alternatives to biologics and broadening treatment choices for various conditions, including diabetes, cancer, and growth disorders, demonstrating comparable efficacy and safety profiles to their reference products. Confirmatory efficacy studies (CES), a requirement mandated by regulatory authorities, are expensive and time-consuming without providing added value. To facilitate the availability of these essential treatments, this study sheds light on the sufficiency of quality and non-clinical aspects in demonstrating biosimilarity, and the implications of waiving CES requirement on the development cost and timeline. Ten Adalimumab biosimilars were assessed for major objections from EMA on the analytical similarity assessment, the number of clinical trials conducted for type I and type III studies, the sample size of each study, phase III studies duration, which reflect CES, and the prices compared to their reference product Humira. Analysed data showed that the use of state-of-the-art analytical methods confirmed high similarity with Humira, with only three biosimilars receiving major objections on their applications, which were resolved using nonclinical studies and deemed unrelative to the safety and efficacy, confirming CES’s lack of value. The median duration for phase III confirmatory efficacy studies was 52 weeks, and the estimated cost for conducting those studies ranged between $20,517,887 and $52,039,597. Adalimumab biosimilars offer up to an 81% price reduction, highlighting the importance of facilitating biosimilars’ availability, the need for eliminating CES and its implication on the development cost and timeline, and the ultimate benefit for the healthcare system.5 0Item Restricted User Modelling with Personas and the Personalisation of a Museum Mobile Guide(Saudi Digital Library, 2024) Almeshari, Moneerah; Dowell, John; Nyhan, JuliannePersonalisation of museum mobile guides (MGs) has become a priority aim for enhancing visitors’ experiences of museums. Since users of an MG are typically first time users and since their usage is for a relatively short session, personalisation should use initial interaction data to associate the user with a particular persona category and thereby infer other facts about the user’s preferences and needs. Using this approach is a solution where data about individual users may be limited and where the individual configuration of a user interface may not be practical or warranted. This thesis contributes to the categorisation approach to user modelling and to the application of that approach to digital MGs. Five studies were conducted to achieve this aim involving 878 participants. In study 1, a face-to-face questionnaire survey of 105 museum visitors investigated the main facts required to identify a visitor persona and explored the preferences of different visitor personas for particular MG features. It was found that visitor persona could be reliably identified using multiple choice questions concerning the two factors of visit motivation and perceived success criteria. Characteristic preferences for certain features could also be associated with particular personas. Studies 2 and 3 were field studies involving visitor interaction experiences with MG interfaces and both questionnaire and observational data were collected. Study 2 (N=60) found significant correlations between different personas and their preferences for particular features. Study 3 (N=118) examined the experience of visitors using a personalised MG and investigated whether their preference for one of three alternative MG interfaces matched their persona. Study 4 focused on users’ preferences for the design of content of the MG. The study was conducted using an online questionnaire (N=260) where participants were given a scenario and asked to imagine visiting a museum and using an MG. Study 5 (N=335) evaluated summatively the use of motivation and perceived visit success criterion questions to identify a visitor’s persona as well as primary preferences results from the prior research. It also investigated personas preferences of other MG features including presentation form, menu and venue navigation tools. The study paradigm attempted to realistically represent the experience of visiting a museum, including navigating between exhibits, choosing which exhibits to see and viewing several exhibits. The behaviour of people in exploring the exhibit and using the MG has been explored in the first four studies at different levels and found differences among personas. These studies taken together indicate that it is possible to identify a museum visitor’s persona using simple MCQs and to provide them with an interface variant they are likely to prefer according to their persona; they show that the experiences of different visitors using different variant interfaces are equally good.7 0Item Restricted Design and Characterisation of Quantum Dot Lasers(Saudi Digital Library, 2024) Alsayyadi, Maryam; Peter, SmowtonAbstract InAs quantum dot (QD) lasers grown on GaAs substrates have demonstrated significant advantages over quantum well devices, including low threshold currents and long-term reliability, particularly for applications on silicon platforms. For longer wavelengths around 1550 nm, InAs QD lasers on InP substrates have been explored; however, limited studies exist for achieving high-performance QD lasers in this range. This work primarily focuses on lasers fabricated from InAs quantum dots (QDs) on InP substrates grown by metal-organic chemical vapor deposition (MOCVD). High performance AlGaInAs/InP multi-quantum-well (MQW) laser diodes are first examined for comparison, with the QW structures exhibiting a gain parameter (NG0) as high as 94.4 cm⁻¹ for 9-QW layer samples. Simulations of AlInGaAs/InP MQW laser diodes highlight the poor performance at high temperature and demonstrate the benefits of incorporating an electron stopper layer. This layer may be useful to reduce thermionic emission and electron leakage while maintaining efficient carrier injection. For samples intended to operate as quantum dots the laser performance is explored and the question as to whether dots, dashes or modulated quantum wells are formed under varying growth conditions is examined. Here performance limitations related to a small optical gain are identified. Epitaxial structures are grown on n-type InP substrates using MOCVD, and broad-area lasers with oxide-isolated stripe widths of 50 μm are fabricated using standard photolithography. The lasers feature uncoated facets, cavity lengths ranging from 300 μm to 2000 μm, and emission wavelengths around 1550 nm. A 5-layer InAs/InP QD laser structure with 0.7 nm capping layers achieved optical gain of approximately 60 cm⁻¹ and ground-state lasing up to 390 K for cavity lengths as short as 330 μm. These structures demonstrate minimal gain saturation, with a G0 per layer similar to the quantum well lasers, showcasing their potential as optical sources for silicon-photonics. Additionally, 3-layer and 5-layer QD structures with 4 nm capping layers are investigated, with their performance under various growth conditions evaluated, including the use of (Al)InGaAs capping layers. Three distinct laser diode structures, each with two fabrication orientations, are analyzed to differentiate between dot and dash morphologies. A multi-section technique is employed to measure modal gain and absorption spectra. At room temperature, internal optical losses ranged from to 15±0.2 cm⁻¹, for quantum dashes (QDH) to 18±2 cm⁻¹, for quantum wells (QW). Peak modal gains of 40±2 cm⁻¹ and 24±2 cm⁻¹ were observed for QW and QDH lasers, respectively, under injected current densities. These findings highlight the potential of InAs/InP QDH lasers for operation on silicon at 1.55μm.14 0Item Restricted Timber Extraction(Saudi Digital Library, 2024) Alsharfa, Zahra; Leandro, MinuchinBuilding with natural materials has been perceived as an important concept in sustainable architecture, and plays a key role in tackling the issue of climate change. Timber, in particular, is one of the most popular natural materials that has been extensively used by architectural practices around the world. This extends to those in the UK who have used timber as an alternative to carbon-intensive materials, like concrete and steel, with the aim to reduce CO2 emissions from the building industry. This dissertation aims to shed light on the other side of using timber in buildings to bring attention to the unnoticed social and environmental effects of the extractivist timber supply chain of the timber trade in the UK. A case study methodology was used in this research. A critical analysis of a UK-based architectural practice ‘Material Cultures’ work was employed, to understand the complexity of the building materials supply chain, focussing mainly on timber. Tracing the work of this practice was particularly useful in exploring alternatives that could tackle the dependency on the extractivist materials supply chain by the construction industry. The results showed that the concept of timber use in buildings as a sustainable solution could sometimes be oversimplified by architects and designers, resulting in some serious social and environmental violations and injustice around the world. Therefore, in order to achieve a true meaning of social and environmental sustainability, the consumers of timber like architects need to consider the process of the timber material chain and be aware of the origins, manufacture and design of the materials they use.7 0Item Restricted The application of the Necessity-Concerns Framework in understanding inappropriate demand for antibiotics in upper respiratory tract infections and COVID-19 vaccine hesitancy(Saudi Digital Library, 2024) Almeshal, Nouf; Horne, Rob; Chan, Amy; Foot, HollyThe National Institute for Health and Care Excellence (NICE) Medicines Adherence Guidelines recommend personalised support to address both practical issues, enhancing patients’ abilities and perceptions that influence motivation to engage with, and adhere to treatment. The perceptions and practicalities approach (PaPA) operationalises key adherence-related beliefs through the Necessity-Concerns Framework (NCF). The NCF proposes that adherence is influenced by patients’ perceptions of their personal need for medication relative to concerns about adverse consequences. Studies across diseases, cultures, and healthcare systems have demonstrated the validity of the NCF in explaining variation in treatment engagement. This PhD thesis aims to examine the application of the NCF to address two behavioural challenges related to respiratory illnesses: vaccine hesitancy and demand for antibiotics to treat upper respiratory tract infections (URTIs). The research includes a scoping review of determinants influencing patients’ demand for antibiotics, a qualitative study involving patients with URTIs, a cross-sectional survey investigating beliefs about antibiotics and AMR, a review of COVID-19 vaccine hesitancy literature, a cross-sectional cohort survey examining differences in beliefs between COVID-19-vaccinated and unvaccinated individuals, and an exploratory analysis of the antecedents of beliefs about COVID-19 vaccine necessity and concerns. The scoping review identified patient demand as an important driver of unnecessary antibiotic prescriptions, influenced by factors that shape the perceived need for antibiotics and are associated with low concerns regarding their use. The qualitative study (n=32) identified determinants influencing perceived need for antibiotics (e.g., type and severity of symptoms) and concerns (e.g., frequent administration of antibiotics), impacting inappropriate demand for and unnecessary use of antibiotics. The cross-sectional study (n=1105) found that intention to request antibiotics was significantly predicted by beliefs about antibiotic necessity (β=0.475, p<0.001), and concerns (β=-.133, p<0.001). The COVID-19 vaccine hesitancy literature review was suggestive of the applicability of the NCF as an effective framework to understand and address this public health issue. The following cohort cross-sectional survey (n = 1012) reported that beliefs about vaccine necessity outweighed concerns about the vaccine and strongly predicted vaccination decisions [OR=1.616, 95% CI (3.001, 8.440)]. This research highlighted the adaptability of the NCF as a theoretical framework for comprehending inappropriate demand for antibiotics and COVID-19 vaccine hesitancy. The findings indicate the potential applicability of a reverse NCF approach in understanding and addressing inappropriate antibiotic demand. It further identified that COVID-19 vaccine hesitancy demonstrated patterns commonly observed in medication non-adherence, specifically characterised by low perceived necessity and increased concerns regarding treatment. The thesis findings potentially laid the foundation that the NCF can effectively inform the design of interventions targeting vaccine hesitancy and patients’ inappropriate demand for antibiotics in the management of URTIs.12 0Item Restricted The Impact of Using MOOCs on Saudi L2 Learners’ Academic Writing Skills(Saudi Digital Library, 2024) Almeshal, Mashael; Kennedy, Eileen; Smidt, Sam; Alnasser, SulimanStudents in higher education institutions (HEIs) are required to complete assignments in which they must utilise advanced language and writing skills to effectively convey information to complete assessments that require them to articulate arguments using scholarly literature and discipline-specific terminology (Coffin et al., 2003; Hassel & Giordano, 2009; Hendricks & Quinn, 2000). This is particularly challenging for non-native English speakers taking courses with English as the medium of instruction (EMI) (Short & Fitzsimmons, 2007), and therefore it is imperative for such students to develop their writing skills. HEIs have implemented measures to support the writing of L2 learners in EMI institutions, such as integrating technology to develop their writing potential. This study proposes a solution utilising a massive open online course (MOOC) to enhance the writing skills of L2 students. This study has the following objectives: (1) to design a writing MOOC by identifying design principles that will effectively enhance its quality, engagement, and learning outcomes; (2) to design and implement the integration of this MOOC into a synchronous learning management system (LMS) experience; and (3) to evaluate the proposed MOOC’s impacts and its integration on writing development in EFL learners. In pursuit of these objectives, a MOOC was designed, developed, and integrated into a synchronous LMS based on Laurillard’s (2012) Conversational Framework. A mixed- method, design-based research approach was employed to evaluate the design and implementation of the MOOC. One cycle of design and implementation was conducted throughout the Spring semester of 2020/2021, drawing on qualitative and quantitative data produced by writing tests, questionnaires, interviews, and an online survey. The results indicate that the design and integration of the MOOC had a positive impact on writing development, while also providing insights regarding student perceptions of the MOOC and its feasibility in blended learning contexts and revealing the usefulness of the Conversational Framework in designing asynchronous and blended learning experiences. As this experience was captured during COVID-19, the design and integration model provided can be utilized in any future educational disruptions.5 0Item Restricted explore the experience of healthcare providers and bereaved next of kin regarding the provision of palliatiive care in adult intnesive care unit: an exploratory study(Saudi Digital Library, 2024) Alshahrani, Hamad; Reid, Joanne; Gormley, Kevinabstract uploaded in full thesis file2 0Item Restricted Characterisation of Semiconductor Nanowires for Use in Semiconductor Lasers(Saudi Digital Library, 2024) Almalki, Nourh; Smowton, Peter; Li, QiangA monolithically integrated III-V light emitting device on silicon-on-insulator (SOI) substrate would considerably simplify photonic integration with Complementary Metal-Oxide-Semiconductor (CMOS) technology. This thesis presents an approach for designing an edge-emitting device with a combined III-V/Si waveguide. High-quality InGaAs nanowires (NWs) can be grown directly on the SOI wafers, free from defects and dislocations. By using these nanowires on an SOI wafer, a hybrid waveguide with a high optical mode overlap between the III-V gain material and the silicon waveguide is designed. The as-grown InGaAs nanowires on SOI substrate are assessed by several techniques, including photoluminescence (PL), Raman, scanning electron microscope (SEM), and energy-dispersive x-ray spectroscopy (EDX) characterisation. Different nanowires with different diameters and periods are examined in this study. These studies reveal that the indium composition in the nanowire arrays is not uniform. Two different indium compositions exist in a single nanowire. A lower indium composition is at the base of the nanowires in the horizontal direction, and a higher indium composition is above the core layer in the vertical direction. Moreover, the density of the nanowire arrays affects the uniformity of the indium composition. Denser arrays show that the indium composition decreased significantly from the edges of the arrays towards the centre of the arrays. These two different indium compositions are responsible for the appearance of the two distinct peaks in the PL and Raman spectra. Additionally, the optical performance of the fabricated waveguide is examined by optical pumping. PL imaging is used to measure the intensity and extract the power efficiency from the waveguide. The study demonstrates a steady-state intensity saturation with a reduction in the power efficiency as the pumping power increases when the measurements are taken from the vertical direction. This behaviour indicates that lasing occurs in the in-plane direction. Furthermore, PL images showing a higher concentration of light near the edges of the nanowire arrays support this conclusion, as the in-plane guided light is strongly reflected at the waveguide boundaries.10 0Item Restricted The application of the Necessity-Concerns Framework in understanding inappropriate demand for antibiotics in upper respiratory tract infections and COVID-19 vaccine hesitancy(Saudi Digital Library, 2024) Almeshal, Nouf; Rob, Horne; Amy, Chan; Holly, FootThe National Institute for Health and Care Excellence (NICE) Medicines Adherence Guidelines recommend personalised support to address both practical issues, enhancing patients’ abilities and perceptions that influence motivation to engage with, and adhere to treatment. The perceptions and practicalities approach (PaPA) operationalises key adherence-related beliefs through the Necessity-Concerns Framework (NCF). The NCF proposes that adherence is influenced by patients’ perceptions of their personal need for medication relative to concerns about adverse consequences. Studies across diseases, cultures, and healthcare systems have demonstrated the validity of the NCF in explaining variation in treatment engagement. This PhD thesis aims to examine the application of the NCF to address two behavioural challenges related to respiratory illnesses: vaccine hesitancy and demand for antibiotics to treat upper respiratory tract infections (URTIs). The research includes a scoping review of determinants influencing patients’ demand for antibiotics, a qualitative study involving patients with URTIs, a cross-sectional survey investigating beliefs about antibiotics and AMR, a review of COVID-19 vaccine hesitancy literature, a cross-sectional cohort survey examining differences in beliefs between COVID-19-vaccinated and unvaccinated individuals, and an exploratory analysis of the antecedents of beliefs about COVID-19 vaccine necessity and concerns. The scoping review identified patient demand as an important driver of unnecessary antibiotic prescriptions, influenced by factors that shape the perceived need for antibiotics and are associated with low concerns regarding their use. The qualitative study (n=32) identified determinants influencing perceived need for antibiotics (e.g., type and severity of symptoms) and concerns (e.g., frequent administration of antibiotics), impacting inappropriate demand for and unnecessary use of antibiotics. The cross-sectional study (n=1105) found that intention to request antibiotics was significantly predicted by beliefs about antibiotic necessity (β=0.475, p<0.001), and concerns (β=-.133, p<0.001). The COVID-19 vaccine hesitancy literature review was suggestive of the applicability of the NCF as an effective framework to understand and address this public health issue. The following cohort cross-sectional survey (n = 1012) reported that beliefs about vaccine necessity outweighed concerns about the vaccine and strongly predicted vaccination decisions [OR=1.616, 95% CI (3.001, 8.440)]. This research highlighted the adaptability of the NCF as a theoretical framework for comprehending inappropriate demand for antibiotics and COVID-19 vaccine hesitancy. The findings indicate the potential applicability of a reverse NCF approach in understanding and addressing inappropriate antibiotic demand. It further identified that COVID-19 vaccine hesitancy demonstrated patterns commonly observed in medication non-adherence, specifically characterised by low perceived necessity and increased concerns regarding treatment. The thesis findings potentially laid the foundation that the NCF can effectively inform the design of interventions targeting vaccine hesitancy and patients’ inappropriate demand for antibiotics in the management of URTIs.2 0Item Restricted Evaluation of diagnostic accuracy and image quality of EOS imaging system in hip assessment with refer to computed tomography(Saudi Digital Library, 2024) Alghamdi, Ahmed Mohammed Ahmed; Amaka C. OffiahAim: This study evaluates the accuracy of the EOS imaging system in assessing pre- and post- operative hip abnormalities compared to the reference standard CT scan, focusing on EOS image quality and patient experience. Materials and Methods: (i) A systematic review and meta-analysis were conducted to compare EOS accuracy with CT for measuring native and prosthetic hip parameters in adolescents and adults. (ii) A prospective analysis of 10 patients assessed EOS diagnostic accuracy for native hips with acetabular dysplasia compared to CT. (iii) A retrospective analysis of 100 patients evaluated mechanical axis measurements by EOS and digital radiographs (DR). (iv) A retrospective analysis of 30 patients reviewed patient experience with CT and EOS. In (i), reliability coefficients were normalised with Fisher’s Z and presented with effect size and 95% confidence intervals in a forest plot. For (ii), three observers independently measured acetabular version, inclination, femur length and spinopelvic parameters on CT, while two assessed the same parameters on EOS. In (iii), three observers scored DR and EOS acetabular morphology according to modified European diagnostic image quality criteria. In (iv), participants completed questionnaires on their experiences. Results: (i) The average correlation across studies was high (r = 0.86, 95% CI = 0.80–0.90, p < 0.001). (ii) EOS showed good agreement with CT for spinopelvic parameters and femur length pre- and post-operatively and acetabular inclination pre-operatively, but lower agreement for acetabular version and pre-operative inclination. (iii) EOS demonstrated high AC1, sensitivity, and AUCs for mechanical axis imaging compared to DR. (iv) Most patients preferred CT over EOS. Conclusion: EOS shows good inter-observer agreement for spinopelvic parameters and femur length compared to CT but poor agreement for acetabular version and inclination. Patients prefer CT, possibly due to familiarity. However, EOS offers better mechanical axis image quality than digital radiographs.9 0