Saudi Cultural Missions Theses & Dissertations
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Item Restricted EVALUATION OF HYDRATION PROTOCOLS FOR HUMAN CORTICAL MINERALIZED PARTICULATE ALLOGRAFTS(Saudi Digital Library, 0025-05-07) Aljowhara, Faraidy; Santana, RonaldoObjective: Bone graft hydration is a critical yet under-explored factor influencing the handling and performance of allograft materials in regenerative procedures. Most manufacturers suggest that biomaterial should be hydrated for at least 30 minutes before use. However, despite widespread clinical use, no standardized hydration protocol exists, and the impact of hydration on the chemical composition, mineralization, and structural integrity of graft materials remains unclear. This study aims to evaluate the physicochemical alterations of mineralized particulate bone grafts following hydration at varying concentrations and time points. Methods: Three commercially available human allograft materials {Straumann Mineralized (SM), Geistlich Mineralized (GM), and Zimmer Mineralized (ZM)} from three different manufacturers, with particle sizes ranging from 250–1000 µm, were examined. The granules were hydrated in 0.9% saline at concentrations of 50 µL and 500 µL and incubated for 1, 10, and 30 minutes. Scanning Electron Microscopy (SEM) was employed to assess hydration-induced structural changes. Chemical composition and molecular alterations were analyzed using Fourier Transform Infrared (FTIR) Spectroscopy and spectral data were processed using second-derivative analysis to improve peak resolution, allowing for the quantification of vibrational bands. Results: SEM analysis revealed no significant differences in surface morphology of the mineralized grafts after hydration. FTIR analysis showed chemical homogeneity across graft materials, with variations in peak intensities reflecting differences in molecular concentrations, mineralization, and collagen integrity. Biomaterial hydration promoted significant selective spectral band increases for all the time points evaluated. Prolonged hydration times did not produce significant or proportional spectral shifts, suggesting a saturation threshold after 1 minute of hydration. Conclusions: Increasing hydration time did not result in significant changes in vibrational bands, suggesting that hydration times longer than 1 minute have minimal impact on the molecular structure of the particulate allografts evaluated.15 0Item Restricted MECHANICAL AND PHYSICAL PROPERTIES OF 3D-PRINTED VENEER MATERIALS(Saudi Digital Library, 2025-06-17) NASIR, ADNAN; Russell, Giordano IIObjectives: This study aimed to evaluate and compare the mechanical and physical properties of two 3D-printed dental veneer material, Rodin Envision and SprintRay OnX Tough 2. The primary focus was on determining minimum printable thickness, flexural strength, fracture toughness, wear resistance, translucency, color stability, surface roughness, gloss retention, and filler content by weight. Materials and Methods: Two resin-based materials were analyzed: Rodin Envision (Pac-Dent, USA) and OnX Tough 2 (SprintRay, USA), fabricated using Asiga Max and Sprintray P95 printers, respectively. Specimens were designed and tested following ISO standards. Minimum printable thicknesses tested were 0.1, 0.2, 0.3, 0.4-, and 0.5-mm. Evaluations included three-point flexural strength, fracture toughness, wear resistance (extrapolated to 1 million cycles), translucency, and surface roughness pre- and post-immersion. Color stability was assessed using three staining solutions: coffee, tea, and 0.1 ppm toluidine blue. Gloss retention was measured before and after thermocycling, and filler content was determined using ash burnout. Microstructural analysis was conducted using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). Results: Rodin Envision demonstrated significantly superior performance in print precision, mechanical strength, wear resistance, and gloss retention. It achieved accurate prints at 0.2 mm and higher, and exhibited higher flexural strength (155.3 MPa vs. 128.2 MPa) and modulus (5.72 GPa vs. 4.16 GPa). Envision also outperformed OnX Tough 2 in fracture toughness, translucency, and gloss retention. However, OnX Tough 2 showed better color stability in tea and retained lower surface roughness after staining. Filler content analysis revealed higher inorganic loading in Envision (51.73%) compared to OnX Tough 2 (35.3%). Conclusion: Rodin Envision presents superior mechanical and physical properties across most tested domains, making it a more suitable candidate for high-performance esthetic dental restorations. OnX Tough 2 may be preferred in clinical scenarios prioritizing color stability and flexibility. These findings underscore the importance of material selection in optimizing the performance of 3D-printed veneers.24 0Item Restricted Biaxial flexural strength of lithium-based CAD/CAM dental glass-ceramics(univirsity of florida, 2025) Alhindi, Saleh; Abdulhameed, Nader; Mateus, Rocha; Roulet, Jean-FrancoisAbstract: Objective: The aim of this study was to evaluate the biaxial flexural strength of four CAD/CAM dental glass-based ceramics containing lithium in the crystalline structure. Material and methods: A universal testing machine is used to evaluate the biaxial flexural strength of four groups of ceramic materials: IPS e.max CAD, GC LiSi Block, CEREC Tessera, and unbranded. Each group contains 20 samples, for a total of 80 samples. In addition to that, the microstructure was examined using SEM. Results were analyzed using one-way ANOVA followed by the Tukey test for multiple comparisons, with statistical significance set at p < 0.05 and a 95% confidence interval. Weibull Analysis was used to assess the biaxial flexural strength and was also based on the 66% log-likelihood parameter for the different ceramics. Result: CEREC Tessera demonstrated the highest BFS, while GC LiSi Block was the lowest. There were no statistically significant differences between IPS e.max CAD, CEREC Tessera, and unbranded (p>0.05), whereas GC LiSi Block exhibited significant differences (p<0.05). The chemical composition and microstructure of the tested samples varied significantly, including the presence of zirconium oxide (ZrO₂) in IPS e.max CAD and distinct crystal morphologies across the materials. Conclusion: Statistically significant differences in biaxial flexural strength (BFS) were observed between GC LiSi Block and the other ceramic groups, with GC LiSi Block exhibiting the lowest flexural strength (p < 0.05). Additionally, the chemical composition and microstructure of the tested samples varied significantly. Therefore, both null hypotheses of this study were rejected. From a clinical perspective, despite these variations, all tested materials exceeded the ISO 6872:2015 threshold of 300 MPa, confirming their suitability for various restorative applications.9 0Item Restricted Instant Messaging and Negotiation Outcomes in Peer-to-Peer Online Marketplaces: The Role of Institutional Trust.(The University of Leeds, 2024) Alamri, Omar; Taylor, AndreaThis study investigates the dynamics of buyer-seller interactions in peer-to-peer online marketplaces and their influence on perceived economic negotiation outcomes. It specifically examines how institutional trust mediates the relationship between negotiation outcomes and the use of instant messaging as a communication tool. Grounded in Media Synchronicity Theory and the institutional based trust framework, this research analyses data from a sample of 152 participants using structural equation modelling. The findings reveal that IM capabilities such as diverse symbol sets, transmission velocity, and rehearsability significantly enhance communication performance, while reprocessability and parallelism do not. Additionally, the study demonstrates that communication performance, represented by mutual understanding, positively affects perceived economic negotiation outcomes, with institutional trust playing a partial mediating role. A key implication of this research is identifying institutional trust as a critical mediator between communication media and perceived economic negotiation outcomes. This highlights the importance of integrating trust mechanisms when assessing the effectiveness of communication tools in online marketplace negotiations. This study distinguishes itself from existing research on communication media and negotiations by employing a comprehensive analytical approach that first evaluates the impact of IM's capabilities on mutual understanding and subsequently examines how this understanding relates to negotiation outcomes, mediated by a third factor, which is institutional trust.19 0Item Restricted A Treatment for Clostridioides difficile Based on Cell Wall Lysins Isolated from C. difficile Specific Bacteriophages(Cardiff University, 2024-04) Alyahya, Khalid Abdullah; Baillie, Les; Heard, Charles; Mehellou, YoucefClostridioides difficile is a Gram-positive, anaerobic, spore-forming bacillus and is a major cause of healthcare-associated infections. While the vegetative form of the pathogen is susceptible to antibiotic treatment, its ability to persist in the gut as antibiotic-resistant spores leads to reinfection in cases where protective microflora is not reestablished. Utilizing recombinant endolysins as treatment of CDI is promising because of their activity against antibiotic and bacteriophage resistant strains. In this study, the recombinantly expressed endolysin LysCD6356 and its enzymically active domain (EAD) were shown to lyse the vegetative forms of a panel of clinical isolates of C. difficile from the UK, including hypervirulent 027 ribotype strains. While these results were promising endolysins, like antibiotics and bacteriophages, endolysins have no effect against the spore form of the pathogen, which is responsible for recurrent infections following successful treatment. To address this issue, a combination of germinants and a bactericidal agent were employed to target the more sensitive form of the pathogen. In this study, exposing of C. difficile spores to germinants followed by endolysin several hours later proved to be the most effective approach suggesting a promising approach to treat relapsing CDI. Additionally, the binding of LysCD6356 and its EAD to the spore and vegetative forms of C. difficile would leave the endolysin ideally placed to target the emerging vegetative cells. This also raise the possibility of developing a diagnostic tool that could be used to detect the pathogen. Bioinformatic studies revealed a significant similarity between LysCD6356 and its EAD to CD27L and CD271-179, respectively, suggesting a possibility of sharing common motifs. However, there was no similarity of LysCD6356 and its EAD with previously published spore binding domains, suggesting the presence of a new spore binding region. An attempt to investigate the binding of endolysins to spore surface proteins, CdeC and CdeM, was unsuccessful possibly due to deficiencies in the experimental approach or the fact that the endolysins recognize other spore surface targets. The combination of our strategy of targeting spores with more traditional approach, such as fecal microbiota transplant, could provide more efficient treatment of relapsing CDI.25 0Item Restricted Understanding the Factors Influencing the In Vitro Corrosion Behaviour of Biodegradable Zinc(The University of Queensland, 2023-11-17) Almathami, Sharifah; Dargusch, Matthew SimonBiodegradable metals (BMs), such as magnesium (Mg), zinc (Zn) and iron (Fe), are envisioned to be the main material that will be used to create the next generation of temporary medical devices. These metals appear to be viable substitutes for permanent metals, such as stainless steel and titanium, in treating temporary medical issues to lower the risk of adverse long-term implant effects. At the core of the application of BMs is a deep understanding of the BMs’ corrosion behaviour in the physiological environment. The purpose of this thesis is to gain a deeper and more comprehensive understanding of the factors affecting the in vitro corrosion behaviour of pure Zn and, to a lesser extent, Fe. A key contribution of this thesis is the examination of the influence of biologically-relevant ions, such as chlorides, carbonates, phosphates, and sulphates, on the corrosion of pure Zn and Fe in simulated physiological fluids. Electrochemical and immersion corrosion techniques coupled with surface analysis tools were employed for this analysis. With respect to corrosion, the most aggressive ions are chlorides, which induce localised corrosion damage on both Fe and Zn. Carbonates and phosphates reduce the corrosive attack of chloride ions on Zn and Fe while inducing a shift to uniform corrosion, though the potency of corrosion-inhibition varies between the two metals. Carbonates induce better corrosion protection on Zn due to the formation of Zn, while phosphates were more effective for Fe. Sulphates reduce the corrosion rate by disrupting the metal’s passive layer generated by carbonate and phosphate ions interaction. The overall corrosion rate of Zn and Fe changed in each electrolyte depending on the composition of the solution and the nature of the corrosion product formed. The influence of electrolyte deaeration (consisting of nitrogen purging) on Zn and Fe degradation in three test solutions, namely, 0.13 M NaCl, Hanks’ balanced salt solution (HBSS) and phosphate buffered saline (PBS) solution, was examined. Deaeration reduced Zn and Fe’s corrosion in the respective electrolyte, inducing an increase in the charge transfer resistance of the metal surface. This is due to the elimination of dissolved oxygen necessary to initiate the oxygen reduction reaction, which is the main cathode reaction driving the corrosion of Zn and Fe in an aqueous environment. Deaeration of the HBSS induced a significant increase in pH, resulting in the passivation of Zn and Fe and the reduction of corrosion rate. Zn in the deaerated HBSS exhibited an atypical polarisation curve consisting of multiple corrosion peaks. This is unwanted as it complicates the proper analysis of the corrosion rate from the polarisation curve. The influence of operating test factors on the measured corrosion rate of Zn from the polarisation test was investigated. Zn’s corrosion rate increased with increasing specimen surface roughness due to the enhanced effective surface area and rise in residual stresses with increasing roughness. The specimen storage time beyond one hour was found to have minimal influence on the corrosion rate of Zn, likely caused by the formation of a stable surface condition during storage. Increasing HBSS storage time increased the corrosion rate of Zn in the solution. The mechanism for the solution's enhanced aggressiveness after aging is still unexplained, though this may be linked to the increase in solution pH at the 30-day aging time or bacterial action. Increasing stirring speed enhances the corrosion rate of Zn in HBSS, particularly above a critical agitation level. Stirring accelerates Zn corrosion by removing corrosion products from the specimen's surface and reducing the associated concentration polarisation effect. High amounts of sodium bicarbonate (NaHCO3) in HBSS enhanced the corrosion rate of Zn. There was an observed delay in passive film formation, causing the surface of Zn to stay active. The mechanism for this delayed passivity still needs to be understood, though it is proposed that the bicarbonate ions were just adsorbed at the surface and did not proceed to form the carbonate film. Using hydrochloric acid (HCl) for pH modification of HBSS enhances the corrosion of Zn, while lactic acid has a less severe influence. Corrosion severity is found to be acid concentration-dependent. The addition of HCl augments the chloride concentration of HBSS and increases the solution’s aggressivity towards Zn. The influence of some test parameters on the measured corrosion rate of Zn from the immersion test was also studied. The corrosion rate of Zn in PBS was significantly higher than that in HBSS, consistent with polarisation experiments. This is likely due to the presence of other ionic components besides phosphates, including carbonates, magnesium (Mg) and calcium (Ca) cations. Zn exhibited a decreasing corrosion rate trend with increased immersion time, consistent with the progressive formation of corrosion-inhibiting surface deposits. The degradation rate of Zn in HBSS increases with decreasing test solution volume (V) at a constant specimen surface area (SA). The influence of SA:V ratio on Zn’s corrosion rate may be associated with the specimen’s access to oxygen during the corrosion test.17 0Item Restricted Advanced Nanomaterial Composites for Enhanced Photocatalysis and Sensing(Saudi Digital Library, 2023-11) Alanazi, Ahmed; James, RiceRecent advances in nanostructuring techniques have contributed to the field of plasmonics. In current research, plasmonic plays an important role in sensing, including surface enhanced Raman spectroscopy (SERS). The fabrication of platforms for optical sensing has traditionally been carried out using costly techniques requiring specialized equipment. These techniques require precious metals, which have limitations in biocompatibility, high environmental impact, cost, and availability. Semiconductors are used in SERS since they provide enhanced Raman signals through their unique optical and electronic properties, allowing for tunability and reproducibility. Their stability and compatibility with various technologies render them valuable substrates for highly sensitive molecular analysis. Furthermore, their additional benefits include cost-effectiveness, recyclability, self-cleaning properties, and flexibility, which make them suitable for potential integration with other technologies. Even though semiconductor-based SERS have been the subject of numerous promising studies, current state-of-the-art designs are largely restricted due to their lower signal enhancements. New designs for SERS substrates are crucial to overcome some limitations and improve the performance of SERS. Existing designs may have limitations in terms of sensitivity, reproducibility, scalability, or compatibility with specific molecules or applications. The aim of the thesis is to investigate the combination of semiconductors and plasmonic nanomaterials in order to develop new designs implementing simple, cost-effective, and environmentally friendly strategies. The combination of plasmonic nanomaterials with semiconductors has great potential for sensing and photocatalysis. This thesis is divided into nine chapters: In Chapter 1, a brief description of Raman scattering and molecular dynamics is presented, as well as Raman-active modes selected based on vibration spectra, light-driven electronics. In the following section, examples are provided of how Raman spectroscopy is used in modern research. Following this, a brief overview of SERS is provided, including electromagnetic and chemical enhancements as well as effects related to wettability. Lastly, the chapter discusses photocatalysis mechanisms and applications, such as chemical oxidation reactions and self-cleaning photocatalysis. Chapter 2 provides an overview of the primary strategies which can be utilized in the design of optical sensing platforms for SERS. Several material classes are discussed as well as their properties that make them useful for chemical detection. First, the primary processes involved in the production of platforms fabricated from precious metals will be briefly reviewed. This method will also be discussed in terms of its advantages and disadvantages. In the following section, alternative semiconductor materials are examined; these materials have the advantage of being biocompatible and easy to fabricate. Several subgroups of semiconductor materials that have been demonstrated to be effective at enhancing optical signals are discussed following an introduction to the two primary categories of semiconductor materials - organic and inorganic. In Chapter 3, a brief overview is presented of the major spectroscopy and microscopy techniques utilized to explore the optical properties and morphology of the manufactured substrates investigated in this thesis, along with the methods utilized to analyze the data. The analysis methodology and experimental specifics of how the measurements were conducted are described in some depth in the text, which presents the overall ideas underlying the analysis. In Chapter 4, investigate the photocatalytic potential of transition metal chalcogenides (TMCs) cadmium sulfide (CdS) when coupled with plasmonic nanostructures. The synthesis of dimercaptoazobenzene (DMAB) from p-amino thiophenol (PATP) was demonstrated by the super bandgap irradiation of a silver nanowire (Ag NWs) and cadmium sulfide composite for PATP. For plasmonic photocatalysis applications, our findings indicate that cadmium sulfide can serve as an alternative to semiconductors, such as titanium dioxide. In Chapter 5 a combination of conducting polymers such as P3HT (poly-3-hexylthiophene) and PcBm (phenyl-C61-butyric acid methyl ester) with plasmonic nanomaterials is demonstrated to enhance Raman scattering spectroscopy signals up to five-fold and to support the oxidation of target molecules by supporting the charge transfer. The purpose of this chapter is to demonstrate how conducting polymers can be used as semiconductor platforms for the development of plasmonic catalysis and sensing techniques. Chapter 6 describes the development of nanocomposites consisting of metals and organic conducting semiconductors, which have the potential to provide a flexible, lightweight platform for plasmon-based sensing. The purpose of this chapter is to demonstrate the use of super band-gap irradiation to provide plasmon excitation and irradiation to remove analytes from a polymer-plasmonic composite based upon the conducting polymers P3HT and PCBM, as well as to support plasmon-enhanced spectroscopic detection. Our research demonstrates that such a polymer-plasmonic composite is an effective self-cleaning system for use as a reusable optical sensing substrate. In Chapter 7, plasmon active metal nanostructures and semiconductors are described as nanocomposites that support catalytic activity. As discussed in this chapter, transition metal dichalcogenides such as MoS2 when combined with metal oxides such as ZnO have the potential to control charge states in plasmonic nanomaterials. The objective of Chapter 7 is to demonstrate the possibility of controlling plasmonic reactions through the careful selection of semiconductors. In Chapter 8, we present a framework consisting of silver nanoparticles (Ag NPs) on Mg-doped lithium niobate surface. The activation of charge transfer processes on this substrate under white light irradiation is demonstrated to support the oxidation of compounds such as p-amino thiophenol. The purpose of this chapter is to highlight the use of doped lithium niobate materials as semiconductor platforms for plasmonic catalysis. Conclusions and future work are discussed in Chapter 9.21 0Item Restricted Factors impacting Saudi women’s adoption of non-traditional dress for use in public: An application of the theory of planned behavior(Saudi Digital Library, 2023) Alghamdi, Rawan; Fiore, Ann-MarieIn Saudi Arabia, women's rights are at the forefront of debate. Modernizing the country includes changes in various aspects of women’s lives, such as the relaxation of the strict public dress code. As of 2018, Saudi women are no longer required to wear traditional abayas (long black abayas with a hair covering and optional face covering) (Abdulaziz, 2019). Presently, Saudi women may choose to wear a fashionable and less conservative dress in public, as long as it is modest and adheres to Islamic guidelines. To date, it appears that research has not examined the factors that affect Saudi women's intention to purchase non-traditional abayas. The purpose of the present study was to examine the factors that impact Saudi women’s adoption of such abayas. The theory of planned behavior (TPB) was utilized. Its three key factors (attitude, subjective norms, and perceived behavioral control) are strong predictors of behavioral intention (Ajzen, 1991). To elucidate how appearance reflects an individual’s public identity, social and psychological aspects of dress theories were reviewed in the present study, including (1) the public, private, and secret self-model (Eicher, 1981), (2) self-concept theory (Sirgy, 1982), (3) symbolic consumption theory (Levy, 1959), (4) extended-self theory (Belk, 1988), and aspect of ambivalence and ambiguity. The objectives of the present study were to measure (1) the impact of the psychographic variables (the need for uniqueness and religiosity) on Saudi women’s fashion innovativeness, (2) the impact of fashion innovativeness on Saudi women’s attitude toward purchasing non- traditional public abayas, (3) the effect of attitude, subjective norms, and perceived behavioral control on Saudi women’s intentions to purchase non-traditional abayas for use in public, and (4) the moderating effect of the independent-self construal on the relationship between subjective norms and Saudi women’s intentions to purchase non-traditional abayas. A quantitative research approach (Creswell & Creswell, 2018) was implemented. A pilot study was conducted with 15 Saudi women to ensure the clarity of the survey’s wording and to determine the amount of time required. An online Arabic survey was distributed among a convenience sample of Saudi women through the social media platform (WhatsApp). A total of 1,101 Saudi women, 18 years old or older, participated in the study. The data were analyzed in three main stages, employing the following statistical tests: (1) exploratory factor analysis (EFA); (2) structural equation modeling (SEM), including confirmatory factor analysis (CFA); and (3) moderation analysis. The result of the EFA revealed that attitude and purchase intention were unexpectedly combined into one variable (attitude/purchase intention). The measurement model for the TPB variables and the combined attitude/purchase intention variable yielded an acceptable fit. Moreover, the structural model revealed the following findings: (1) the need for uniqueness had a nonsignificant impact on fashion innovativeness, (2) religiosity had a significant (but reverse) effect on fashion innovativeness, (3) fashion innovativeness had a nonsignificant impact on attitude toward purchasing non-traditional abayas, (4) subjective norms had a significant positive impact on attitude/purchase intention and perceived behavioral control, and (5) perceived behavioral control had a nonsignificant impact on attitude/purchase intention. Furthermore, the moderating effect of independent self-construal on the relationship between subjective norms and Saudi women's intentions to purchase non-traditional abayas was found to be statistically nonsignificant. The results of the fully recursive model showed the addition of six significant paths; the need for uniqueness and religiosity each had a significant direct effect on subjective norms, perceived behavioral control, and attitude/purchase intention. The absence of confirmation regarding the TPB has theoretical implications for scholars who study consumer behavior in a collectivist society. However, incorporating antecedent variables, in this case--need for uniqueness and religiosity--to the TPB model may enhance its ability to predict collectivist consumers’ behavioral intentions. The findings have the potential to benefit marketers in Saudi Arabia by enhancing their understanding of the factors that influence Saudi women’s intention to purchase non-traditional abayas. For instance, the findings suggest take religiosity level should be taken into consideration when segmenting consumers.21 0Item Restricted Synthesis and Optimisation of Diopside Glass-Ceramics for Dentistry and Biomedical Applications.(Saudi Digital Library, 2023-12-20) Almusali, Mustafa Hassan E; Faris, TamaraAim: To synthesise new high strength Diopside glass-ceramics based on diopside solid solution system, that would be thermally compatible with yttria-stabilised zirconia polycrystalline (YTZP) substrates. This may address YTZP clinical failure rates, due to failure of the veneering material. Methods: A series of experimental glasses were designed using an Appen model and synthesised using melt quench methods. Glasses were then ball milled to achieve different particle sizes (<125 and <45 microns). The glasses were characterised using X-ray diffraction (XRD), dilatometry and differential scanning calorimetry (DSC) to find optimised nucleation curves. Two-step heat treatments were carried out for the glasses to make Diopside glass- ceramics. Glasses and Diopside glass-ceramics were characterised using secondary electron imaging (SEI), magic angle spinning nuclear magnetic resonance (MAS-NMR) and XRD. Optimised Diopside glass-ceramic (group 1) and IPS e.max Ceram (group 2) were veneered onto YTZP substrates to form bilayered specimen groups (n=30 per test group). The biaxial flexural strength (BFS) of the experimental Diopside glass-ceramics, IPS e.max Ceram ceramic and the bilayer specimen groups were tested using the ball on ring test at a crosshead speed of 1mm per minute. Results: XRD revealed that all glasses synthesised were amorphous, while glass-ceramics showed a major Diopside crystal phase and some formulations albite and wollastonite as minor phases. Dilatometry showed thermal expansion coefficients (CTE) ranging from 8.40-10.99 3 x10-6/k which was within the range thermally compatible with YTZP (10.86x10-6). DSC showed sharp nucleation peaks with little shift in crystallisation peaks for glasses at different particle size, suggesting bulk crystallisation. SEM of the glasses showed homogenously distributed spherical domains, while the glass-ceramic indicated dendritic, elongated diopside crystals and an interconnected unique microstructure with no microcracking present in the glassy matrix. MAS-NMR of 27Al of the diopside glass-ceramics showed two broad peaks, the major corresponding to tetrahedral aluminium (Al) and the other peak corresponding to octahedral aluminium (Al), which suggested the presence of a solid solution. Diopside glass-ceramics resulted in a high BFS (152.8 -196.7 MPa) which was significantly (p<0.05) higher compared to commercially available material IPS e.max Ceram (103.2 MPa). The BFS of experimental diopside glass-ceramic veneered onto YTZP showed high BFS (510.1MPa) which had a significantly higher (p<0.05) BFS when compared with IPS e.max Ceram veneered onto YTZP (324.7 MPa). Conclusions: A range of high strength (152.8 -196.7 MPa) diopside glass-ceramics were synthesised which were thermally compatible (8.40-10.99-x10-6/k) with YTZP. When veneered onto YTZP they produced a high BFS (510.1 MPa) that might help to reduce or preventing chipping failure rates encountered in veneered YTZP restorations.29 0Item Restricted The Role of Co-Operative Education: An Effective Strategy to Tackle the Unemployment Rate among University Graduates in Saudi Arabia(Saudi Digital Library, 2023-12-17) Alsadoon, Abdulaziz Mohammed; Rodgers, PeterAccording to the latest statistics 1.5 million students are currently enrolled in universities in Saudi Arabia and the enrollment is expected to reach 04 million by the year 2025 (ICEF Monitor, 2018). With the rapidly growing number of graduates entering the job market every year, the unemployment rate among the university graduates has become a pressing concern for the society and the Saudi Arabian government. The main aim of the current study is to examine the role of cooperative education in reducing the unemployment rate among university graduates in Kingdom of Saudi Arabia. The study is based on a thorough analysis of the body of literature on cooperative education, exploring its role in student development and understanding the factors affecting employability of university graduates. Secondary data related to the number of graduate students passed in past three batches (Viz. 2021, 2022 and 2023) and the employment rate was collected from the College of Business Administration, King Saud University. Further, survey by questionnaire method was used to collect primary data from 116 university graduates for testing proposed hypotheses. Simple random sampling was used to select the respondents from the pool of the student data obtained from the varsity. Descriptive analysis was employed to analyse the seconday data and Partial least square structural equation modelling (PLS-SEM) was performed to test the various causal relationships between exogenous, intermediate and endogenous variables. The study found that there is a significant positive impact of the quality and effectiveness of training program on critical thinking & problem analysis, adaptation to work environment, commitment & sense of responsibility, professional networking opportunity and communication skills of the Saudi graduates. It signifies the positive role played by the cooperative training programs in making management graduates industry ready. The study also found that critical thinking & problem analysis, adaptation to work environment, commitment & sense of responsibility, professional networking opportunity and communication skills has significant positive impact on the chance of employability. Communication skills was reported as the strongest antecedent of the chance of employability and also the top outcome of the cooperative training program. The study emphasizes that cooperative education programs play a significant role in reducing the unemployment among university graduates by developing symbiotic connection between education & industry and empowering the students with required skills necessary to flourish in competitive job market. To fully achieve the benefits, strategic investment and collaborative efforts of academia and industry are necessary to design sustainable training programs that are consistent with the continuously evolving needs of the Saudi Arabian economy. The study provides valuable insights and roadmap for academicians, policy makers and industry for collaborative actions to tackle the rising unemployment issues in economy.42 0