Saudi Cultural Missions Theses & Dissertations
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Item Restricted Characterisation of peroxisomes metabolism and segregation in yeast(University of Sheffield, 2024) Sumaily, Ibrahim Y Y; Rafferty, John BEukaryotic cells are distinguished by the presence of membrane-enveloped structures, called organelles. Organelles play a vital role in cellular organisation as they create unique intracellular microenvironments that sustain the complex metabolism of eukaryotic cells. One of these structures is entitled the peroxisome. Peroxisomes contributes to cell’s metabolism, particularly to fatty acid beta-oxidation. Although the role of peroxisomes in metabolism has been extensively studies in the model yeast Saccharomyces cerevisiae, and many of the proteins involved in peroxisome metabolism have been identified in this yeast. The peroxisome proteome of most other yeasts is still uncharacterised and identification of pivotal proteins that illustrate the biochemical reactions that take place within this organelle and therefore its metabolic functions is unexplored. Limited approaches have been used to identify peroxisomal proteome. In this study, I focused on the yeast Debaryomyces hansenii, an organism known for accumulating high amount of lipid and used in biotechnology research. Initially potential peroxisomal proteins were identified via bioinformatic research, particularly identifying Peroxisome Targeting Signals type 1 and type 2 containing proteins (PTS1 or PTS2, respectively). In addition, a relatively new technique entitled proximity-dependent labelling (BioID) was utilised by fusing a promiscuous E. coli biotin ligase mutant (BirA*) to green fluorescent protein containing a strong PTS1. The BioID enriched proteins were identified via mass spectrometry and analysed in terms of their peroxisome targeting signal, function, predicted metabolic function pathway and related information. Multiple proteins were identified containing a PTS1. Interestingly and surprisingly, two proteins involved in amino sugar metabolism were identified implying a new role for fungal peroxisomes in amino sugar metabolism. This shows the validity of the approach to identify new peroxisomal functions in less well studied organisms. In the second part of this thesis I report the structural analysis of Pex3-Pex19 interaction in S. cerevisiae. AlphaFold prediction was employed to analyse the interaction of the Pex3 C-terminal domain and with the Pex19 N-terminus. The predicted structure suggested a series of electrostatic interactions. The predicted interactions between Pex3 and Pex19 were tested by mutagenesis of Pex19 and analysis in vivo confirmed a loss of Pex19 function in peroxisome biogenesis. Additionally, a preliminary genetic screen was designed to identify potential regulators of the Inp1-Pex3 tethering complex, particularly kinases, phosphatases and ubiquitin ligases. Multiple candidates were identified and classified according to their effect, further investigation is required to understand how these candidates regulate the tether. In summary, this study furthers our understanding of the functions of fungal peroxisomes and their biogenesis.9 0Item Restricted Investigation into the effect of a custom-made jig to enhance guide plane preparation and partial denture framework retention(Queen Mary University of London, 2024-07) Alokla, Mohammad; Patel, Mangala; Friel, TimTooth loss is a common disease and removable partial denture (RPD) is an option to replace missing teeth. One of the major issues of RPDs is reduced retention. Guide plates are RPD components that restrict the path of insertion and improve frictional retention. Dental practitioners have to prepare parallel guide planes on abutment teeth which is difficult to achieve clinically. The invention of a custom cutting guide using computer-aided design and computer-aided manufacture (CAD-CAM) technology by 3Shape TRIOS® software may enhance the accuracy of preparing parallel guide planes, thus improving the RPD retention. The aim of this project was to create a cutting guide using a novel process in CAD-CAM technology and investigate the effect on guide plane preparation and RPD retention. In this project, a bounded saddle master model was selected and duplicated into 40 printed resin models. Four abutment teeth were included in the tests. The upper right second molar (UR7), the upper right first premolar (UR4), the upper left second molar (UL7), the upper left first premolar (UL4) were utilized. The duplicated models were divided into two groups. In the first group (A), 20 cobalt-chromium (Co-Cr) frameworks were fabricated without guide plane preparation for 20 printed models, and the frameworks retention were assessed. In the second group (B), 20 Co-Cr frameworks were designed and fabricated based on prepared guide planes on 20 models. The guide plane preparations of group B were performed using a custom-made jig. The model base was used as a standardised reference for designing the jig and assessing the accuracy of guide plane preparations. The retention of group B frameworks were measured and the accuracy of guide plane preparations were evaluated. The results showed that the average of maximum load for testing retention of RPD frameworks was 1.887 ± 2.779 N (N=Newtons) in group A unprepared models and 0.350 ± 0.575 N in group B prepared models. The accuracy assessment of prepared guide planes in group B showed that the average angle between the model base and UR7 guide plane was 102⁰ ± 1.21 degrees. The average angle between the model base and UR4 was 93⁰ ± 1.86 degrees. The average angle between the model base and UL4 was 92⁰ ± 2.03 degrees. The average angle between the model base and UL7 was 103⁰ ± 2.39 degrees. Also, the measurement of parallelism between opposing guide planes on the right and left bounded saddles of prepared guide planes in group B showed that the average angle on the right side between UR7 and UR4 was 15⁰ ± 2.47 degrees, and the average angle on the left side between UL7 and UL4 was 15⁰ ± 3.36 degrees. Lastly after guide plane preparation in group B, the average of maximum depth tooth reduction on UR7 0.38 ± 0.09 mm, UR4 0.36 ± 0.09 mm, UL4 0.43 ± 0.14 mm, and UL7 0.42 ± 0.11 mm. In conclusion, the resin custom-made Jig that was designed using 3Shape software resulted in non-parallel guide planes and divergent guide plane angle which reduced retention of Co-Cr frameworks in group B prepared models compared to group A non-prepared models. Therefore, the chosen design of the jig negatively influenced the accuracy of guide plane preparation and framework retention. 14 0Item Restricted Exploring the impact of various leadership styles on nursing turnover in healthcare organisations: a systematic review(Saudi Digital Library, 2023-11-03) Almalki, Abdulmajeed Ali Saeed; Brown, Michael; Rainey, DeborahBackground: In healthcare, nurse managers utilise diverse leadership approaches, such as the transformational, passive-avoidant, transactional, situational, servant, laissez-faire, and compassionate styles, in order to develop nurses' competencies, relationships, culture, and values. Many studies have examined the implications of these leadership styles on nurses’ behaviour and experiences in various clinical settings. The relationship between these styles and nurse retention or turnover is complex because it depends on several factors including empowerment, fostering a positive work environment, effective communication, and continual support. Although current systematic reviews emphasise the effect of leadership styles on nurse competencies and patient outcomes, they do not explicitly reveal the influence of these styles on nurse retention and turnover. Aim: This study aims to determine the influence of nurse leadership styles on nurse retention and turnover. Methods: A systematic literature review was conducted using online databases such as CINAHL, MEDLINE, Cochrane Library, ERIC, and EMBASE, spanning September 2013 to 2023. The research question was formulated using the PEO model (Population, Exposure, Outcome) to ensure clarity and relevance. Relevant studies were examined, with measures taken to avoid redundancy. Specific eligibility criteria were used for study selection. Results: Eight articles met the inclusion criteria. These qualitative studies were carried out across a variety of countries and settings, to investigate the impact of leadership approaches on nurse retention and turnover. The articles exhibited minimal bias as assessed by the CASP checklist. A thematic analysis highlighted the importance of certain leadership characteristics for nurse managers. These characteristics included support, adept communication, respect, a visionary perspective, and proactive initiative. Such leadership styles improved nurse retention by encouraging competency development, innovation, adaptive change, and cultivating a positive atmosphere. Conversely, poor leadership practices diminished nurse satisfaction and increased their intention to leave clinical roles. Notably, transformational leadership was viewed favourably. Conclusion: Healthcare nurses’ commitment, retention, and satisfaction are directly impacted by leadership styles. This review underlined how specific attributes and qualities of leaders can significantly improve nurse dedication and morale. The most effective leadership style in relation to retention is transformational leadership, which fosters an environment that values creativity, inclusivity, and teamwork. These can be combined with other effective leader attributes, such as ethical leadership and spiritual leadership, to increase nurse retention and drastically reduce turnover. These findings can help inform related policy, clinical practice, education, and practice development to improve nurse retention and reduce turnover.18 0Item Restricted Improving the retention of resin-based sealants in paediatric dentistry- A literature review(Saudi Digital Library, 2023-11-01) Alsaadi, Waad Eidhah; Silikas, NikolaosThe effectiveness of resin sealants in preventing occlusal caries in children and young adults is well documented in the literature. This paper reviews the recent evidence and discusses the development of pits and fissure sealants in dental practice. It also, covers the different factors affecting the retention of resin sealants in paediatric dentistry, the cost-effectiveness, and the economic implications of dental sealants in high caries risk children as well as the optimal time to review fissure sealants. It was concluded from this review that resin sealants by far is the most effective method in preventing occlusal caries and arresting its progression in high caries risk children. Also, it was evident that the success of resin sealants retention depends on multiple factors and its application considered a technique sensitive and required multiple clinical steps. Therefore, caries risk assessment prior to sealant application was recommended for optimal cost- effectiveness. Lastly, incorporating regular review of sealed teeth as a part of the child’s recall visits is crucial to ensure maximum retention and to maintain its caries preventive effect.73 0Item Restricted An investigation of AI in talent management in luxury hospitality in the UK (United Kingdom)(Saudi Digital Library, 2023-09-29) Alshalah, Zahra; Marinakou, EvangeliaAn investigation has been conducted into the implementation of artificial intelligence in the luxury hospitality sector of the United Kingdom. Digitalization is influencing the business operations of the hospitality sector from a variety of perspectives, including talent management. Managing talent is critical to the success of business operations in the luxury tourism sector, since it is a fundamental component of providing a better level of service to customers. There is no doubt that the hospitality industry is one of the largest in the United Kingdom. Hoteliers have been assisted greatly by artificial intelligence in managing their talent in recent years. Yet most human resources managers in luxury hotels in the United Kingdom are unaware of the existence of this technology, which is the reason for their slow growth. The purpose of this specified dissertation paper is to provide an in-depth analysis and discussion regarding the various challenges that various HR managers are undergoing while implementing AI technology within the hospitality industry in the UK. As well as the variety of approaches through which these challenges can be mitigated, this article discusses various ways through which all of these challenges can be mitigated. Artificial intelligence has been found to be able to facilitate the recruitment process. By doing so, Human Resources professionals have been able to reduce their workload. Additionally, it is used to train employees, make cognitive decisions, and select resumes for employment.131 0