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A Virtual-Reality-Based Dental Simulator for Endodontics with Automated Formative Feedback
No full textAdvancements in virtual reality (VR) and haptic technology are transforming the landscape of medical and dental education, offering new avenues for safe, immersive, and repeatable training experiences. Within dentistry, endodontics presents unique challenges for preclinical education due to anatomical complexity, limited access to extracted teeth, ethical concerns, and the shortcomings of conventional plastic models. Despite endodontics specific plastic teeth being available, they fall short of replicating the hardness of real extracted teeth, are relatively costly compared to generic plastic teeth, and are ultimately a disposable item which makes them inadequate as a sustainable long-term solution. Extracted teeth do a much better job in terms of drilling sensation, although there exist ethical and hygienic concerns around the practice of reusing extracted teeth for preclinical training. Moreover, extracted teeth usually are in short supply and with limited variability in terms of anatomy and mostly diminished structure. This thesis addresses these issues through the development of a VR-based dental simulator focused on endodontic access cavity preparation, delivering both authentic anatomical modeling and automated, objective feedback. The system integrates detailed tooth anatomy segmented from Cone Beam Computed Tomography (CBCT) scans, real-time mesh deformation via a voxelization and marching cubes workflow, and a haptic feedback device to recreate the tactile sensations essential for dental procedures. Performance optimization strategies, such as mesh chunking, lightmapping, and dynamic input options, ensure smooth, immersive experiences adaptable to users’ needs and hardware variations. The simulator’s standout feature is its automated formative feedback mechanism, which compares student performance voxel-by voxel to expert benchmarks, generating both numerical scores and location-specific, descriptive comments that promote self-guided skill improvement. User studies involving undergraduate dental students, most new to VR, demonstrated high engagement and perceived value, particularly in terms of independence, realism, and clarity of assessment. Areas for further development, such as enhanced anatomical detail and differentiated tactile response, were also identified through structured questionnaires and open-ended feedback. Through the questionnaire, the students rated the user friendliness of the simulator at 3.69/4.00, the visual and auditorial accuracies and immersion at 2.70/4.00, the haptics and tactile feel at 2.28/4.00, the scoring feedback and presentation at 3.56/4.00, and lastly their perception of its long-term effectiveness in skill acquisition at 3.17/4.00. The findings support the viability and significant benefits of immersive, automated VR simulators in dental education and their potential to enable objective, scalable, and resource-efficient training
Ottoman Wikālas in Cairo: Islamic Architecture Beyond the Mosque
Full text linkThis thesis traces one of the largest architectural typologies in Cairo: the wikāla, a type of urban caravanserai unique to Egypt. Estimated to have reached more than five hundred buildings by the 18th century, the wikāla was the building of choice for most patrons in Ottoman Cairo. This study initially investigates the evolution of commercial architecture within the Islamic city. It then explores the defining architectural features of Cairene wikālas built between the 16th and 18th centuries—their plans, decorative/iconographic programs, and urban distribution—based on waqfiyyas, chronicles, travelers’ accounts, and photographic archives. Since many of these buildings are no longer extant and have not been fully documented in previous studies, a catalogue of Ottoman wikālas in Cairo, including unlisted buildings, was compiled as part of this study. By reconstructing Ottoman wikālas within their historical context, this thesis raises several questions about the methodological approaches associated with the study of Islamic architecture. It reassesses the validity of the mosque-centered framework for evaluating stylistic evolution by emphasizing the shifting patterns of patronage that accompanied Ottoman rule. Moreover, this study argues that the architectural waqfs of Ottoman Cairo were much larger than previously assumed, and were accompanied by an intentional building program and urbanization scheme. Finally, the thesis highlights the major role wikālas played in Ottoman Cairo’s scholarly milieu, serving as non-Sunni madrasas, spaces of manuscript production, and academic extensions of al-Azhar. This demonstrates that commercial space was closely tied to religious practice in the Islamic city
Targeting the CD47/Calreticulin axis in Triple Negative Breast Cancer using HA grafted Chitosan nanoparticles loaded with Doxorubicin and Polygodial
Full text linkBackground: Triple-negative breast cancer (TNBC) is considered the most aggressive subtype of breast cancer. Although progress in cancer treatment has led to better results for different types of breast cancer, TNBC remains particularly challenging due to persistent resistance to both chemotherapy and immunotherapy. This resistance ultimately renders chemotherapy less effective and is frequently associated with substantial side effects. Immunosurveillance significantly impacts the onset of cancer, the rise of resistance to therapies, and the likelihood of tumor recurrence. In this immunomodulatory process, Cluster of Differentiation 47 (CD47) and Calreticulin (CALR) are two key regulators. CD47 expression is strongly linked to anti-phagocytic signaling, whereas the role of CALR expression in immunomodulation and TNBC progression remains contradictory. Many natural compounds, including Doxorubicin (DOX), have demonstrated strong anti-cancer activity against TNBC. However, like other chemotherapeutic agents, their use is often limited by low efficacy, significant side effects, and a high tendency for the development of resistance.
Aim: The primary objectives of this study were, first, to explore the effect of sublethal chemotherapy doses on surrogate markers of immune cells that might be involved in chemotherapeutic resistance. Building on this, the study aimed to leverage this potential chemoresistance mechanism to develop a safer and more effective therapeutic platform for treating TNBC. To achieve these goals, two main strategies were proposed: the use of natural chemotherapeutic agents in combination at sublethal doses, and the implementation of nanoparticles (NPs) for receptor-mediated drug delivery.
Methods: This comprehensive study was divided mainly into two main parts. First, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays of DOX and Polygodial (PG) were conducted on MDA-MB-231 cells to determine their respective sublethal concentrations. Subsequently, total RNA was extracted, and quantitative real-time polymerase chain reaction (qPCR) was performed to evaluate the impact of these sublethal doses, both as monotherapy and in combination therapy, on the expression levels of CALR and CD47 in MDA-MB-231 cells. Secondly, HA-grafted CTN NPs (HA-CTN NPs) were synthesized, co-loaded with DOX and PG, and extensively characterized. MDA-MB-231 cells were then treated in vitro with the nano formulation. Sublethal concentrations were identified using the MTT assay, followed by quantitative analysis of CD47 and CALR mRNA expression levels in NP treated cells compared to untreated controls.
Results: Treatment of MDA-MB-231 cells with either DOX or PG at sublethal doses resulted in a significant upregulation of CD47 mRNA expression. Notably, CALR mRNA expression was also elevated, particularly at the lowest sublethal concentration of DOX, compared to vehicle-treated control cells. A reversal of immunomodulatory resistance was achieved by sublethal doses of a combination of DOX and PG, which was further amplified through drug delivery via HA-CTN nanoparticles. Combination and nano-formulated treatments led to a marked reduction in intracellular CD47 and CALR expression levels, along with a significant shift in the CD47/CALR mRNA ratio to below 1.
Conclusion: Sublethal doses of the DOX and PG combination were able to evade CD47/CALR-surrogate marker of immunosurveillance in TNBC cells in vitro, outperforming DOX or PG monotherapy and untreated controls. Since immunomodulation is a key factor in cancer development, spread, and recurrence, our findings propose a promising strategy for both effective and safe chemotherapy, as well as a potential option for maintenance therapy. Notably, the HA-CTN nano formulation alone exhibited immunomodulatory properties, and when loaded with the combination therapy, it achieved comparable levels of CD47/CALR mRNA expression at significantly lower drug doses
Copper Metal Organic Framework-based Nanomaterial for Non-enzymatic Glucose Electrochemical Sensor
No full textThis thesis examines the development of non-enzymatic glucose sensors by engineering advanced electrode materials based on metal-organic frameworks (MOFs). Conventional enzymatic glucose sensors, although widely used, suffer from inherent limitations, including poor long-term stability, narrow operating conditions, and sensitivity to environmental factors, due to their reliance on biological enzymes. Non-enzymatic sensors offer a more robust alternative by enabling direct electrochemical oxidation of glucose on engineered electrode surfaces. MOFs represent a highly tunable class of hybrid materials with structural and chemical features that are ideal for sensor applications, including a high surface area, tailored porosity, and excellent thermal and chemical stability. This work focuses explicitly on copper-based MOFs (Cu-MOFs), which have demonstrated promising electrochemical activity and redox behavior suitable for glucose detection. A key objective of this study is to optimize the material composition by systematically investigating the effect of the metal-to-linker ratio on the structural, morphological, and electrochemical properties of the resulting MOFs. The synthesized materials were characterized using various techniques, including XRD, SEM, BET, and electrochemical methods, to evaluate their performance as electrode materials. Results show that fine-tuning the metal-to-ligand ratio has a significant influence on the sensor’s sensitivity, selectivity, and stability. Optimized Cu-MOF electrodes exhibited enhanced electron transfer kinetics and higher catalytic activity toward glucose oxidation. This research highlights the critical role of material design and compositional engineering in the development of high-performance, enzyme-free electrochemical glucose sensors
The Asymmetric Impacts of ESG Performance on Firms Profitability: Evidence From Selected European Economies (2010-2024)
No full textThis thesis studies the impact of Environment, Social, and Governance (ESG) performance on firm financial performance, measured by net income, across Austria, Belgium, France, Germany, the Netherlands, Switzerland and Luxemburg during 2010-2024. Using fixed effect regression, the study investigates the moderating role of firm size across eleven industries, including basic materials, consumer discretionary, consumer staples, energy, financials, health care, industrial, real estate, technology, telecommunications and utilities. The findings show that ESG performance have asymmetric impact on firm profitability, with larger firms experiencing stronger and more significant positive effects. Sectoral analysis reveals variations across industries, with positive effects concentrated in financial, healthcare, and industrial sectors, while other sectors exhibit weaker or negative outcomes. Comparison of Incumbent firms and new entrants shows that ESG-related financial benefits are stronger for new entrants, which entered the market in the post-pandemic period. To ensure the robustness of the results, a two-stage least squares (2SLS) approach is employed, the findings support the main results, confirming the size dependent effect of ESG performance on firm profitabilit
Influencer Wisdom As A Conceptual Model To Understand Influencer Strategies, Tactics, And Success
No full textThe global influencer marketing industry, valued at over $16 billion, lacks frameworks for understanding responsible and sustainable influence practices. While current research focuses on metrics-driven success measures, this study addresses the gap between commercial achievement and ethical influence by developing a comprehensive Influencer Wisdom Framework. Drawing from wisdom theory, consumer behavior research, and social cognitive theory, this research extends the concept of wisdom to digital influence contexts through qualitative investigation of successful influencer practices.
Twenty in-depth interviews with diverse influencers across multiple platforms and niches were analyzed using systematic thematic analysis. The study identifies five interconnected dimensions of influencer wisdom: Intentionality and Authenticity (deliberate commitment to genuine self-expression), Ethical Contemplation (systematic consideration of moral implications in partnerships and content), Purpose-Driven Impact (creating meaningful value beyond personal gain), Emotional Mastery (sophisticated management of psychological challenges), and Growth Mindset and Openness (commitment to continuous learning and adaptation).
The framework reveals that sustainable influencer success requires balancing measurable outcomes with unmeasurable wisdom factors, challenging industry emphasis on quantitative metrics alone. Findings demonstrate how wisdom-based practices create deeper audience connections, more resilient careers, and positive social impact. This research contributes to influencer marketing theory by providing the first comprehensive framework for responsible influence practices, offering practical guidance for creators, brands, platforms, and educators while establishing foundations for future research in digital career development and ethical technology use
Resilience by Design: A Multi-Metric Assessment of Urban Vulnerability across Human-Centric, Built, and Climatic Environment Dimensions
No full textUrban resilience and sustainability have emerged as fundamental imperatives in contemporary urban planning, as cities face mounting pressures from climate change, population growth, and increasing socio-economic disparities. Resilient urban systems are not only those that withstand shocks, but also those that ensure the long-term well-being, equity, and functionality of their environments. As such, advancing the capacity to systematically evaluate resilience across spatial and temporal scales is critical to informing adaptive, forward-looking planning strategies. Despite a growing body of research on urban resilience, prevailing approaches remain limited in scope and resolution. Many studies tend to examine resilience through isolated lenses—focusing either on infrastructure, environmental risk, or socio-economic vulnerability—without capturing the interconnected nature of these domains. Moreover, commonly used metrics are often derived from coarse, aggregated datasets that obscure the structural and morphological characteristics of urban form. As a result, current frameworks frequently fail to reflect the lived reality of cities and the ways in which urban fabric, microclimate, and service accessibility intersect to influence resilience outcomes. The objective of this study is to develop and apply a spatially explicit, multidimensional Urban Resilience Index (URI) that integrates human, built, and climatic dimensions in order to capture the layered and interdependent drivers of resilience at the neighborhood scale. Drawing from high-resolution geospatial data, the framework moves beyond conventional top-down indicators to capture the physical logic and environmental performance of the city. It introduces three nested and interrelated composite indices—the Climatic Resilience Index (CRI), Built Resilience Index (BRI), and Human Resilience Index (HRI)—which are synthesized into a comprehensive Urban Resilience Index (URI). At the broadest scale, the CRI captures the influence of local environmental and microclimatic conditions that frame the city\u27s exposure and adaptive capacity. Enveloped within this context, the BRI assesses the structural and spatial logic of the built environment—its form, configuration, and connectivity—as the mediating layer through which climate is filtered and resilience is materially embedded. At the core lies the HRI, which reflects how effectively urban environments translate physical and environmental conditions into equitable, livable, and supportive spaces for human life. Together, these indices form a layered understanding of urban resilience—one that acknowledges the foundational role of climate, the structuring force of built form, and the ultimate goal of human well-being. Through spatial clustering and comparative analysis, the framework reveals distinctive resilience profiles across the city, highlighting zones of both vulnerability and strength. The results demonstrate that resilience is not uniformly distributed and that trade-offs often emerge between dimensions—for instance, areas exhibiting environmental robustness may lack connectivity or morphological efficiency, while zones designed for accessibility may be more exposed to climatic stressors. These findings underscore the necessity of integrated, place-specific strategies that account for the complexity of urban systems rather than relying on generalized or siloed approaches. By bridging disciplinary boundaries and embedding resilience within the spatial structure of the city, the proposed framework offers a robust foundation for evidence-based planning. It advances the discourse on resilience from abstract principles to operational tools, enabling more responsive, equitable, and climate-conscious urban futures
Self-Medication and Pharmaceutical Dispensing in Egypt: Practices, Policies, and Regulatory Challenges
No full textAccess to safe and appropriate medications is a critical component of public health, particularly in low- and middle-income countries. In Egypt, self-medication and informal pharmaceutical dispensing have become deeply embedded practices shaped by systemic, economic, and cultural factors. This research explores the complex interplay between self-medication behaviors, pharmaceutical regulation, and healthcare access in Egypt. Through qualitative interviews with policymakers, pharmacists, physicians, industry professionals, and citizens, the research uncovers widespread informal dispensing of prescription-only medicines, driven by high out-of-pocket costs, limited insurance coverage, and high public reliance on pharmacists as primary care providers. Despite the presence of regulatory frameworks, weak enforcement, lack of technological and human resources, and limited public awareness hinder effective governance. The study concludes with evidence-based policy recommendations to enhance regulatory enforcement, improve healthcare access, integrate pharmacists into formal care, and strengthen public education, offering a path toward safer and more equitable medication practices in Egypt
Green Roofs for Grey Water Treatment – Comparative Study of Economic and Environmental Impacts
No full textCities are under more pressure than ever to use sustainable methods for managing water and other resources because of urbanization, climate change, and a lack of water. Standard greywater treatment systems (SGTSs) work well, but they use a lot of resources and don\u27t provide a lot of ecosystem services. Greywater-treating green roofs (GTGRs) have emerged as a promising Nature-Based Solution (NBS), combining wastewater recycling with benefits like regulating temperature, reducing greenhouse gas (GHG) emissions, and reducing the urban heat island (UHI) effect. Even with this potential, there is still not enough real-world research on how GTGRs affect both the economy and the environment, especially in different regions. This thesis fills this gap by comparing GTGRs to SGTSs, focusing on both environmental and economic results.
This study aims to evaluate ‘intensive modified’ and ‘integrated systems’ GTGR intakes through cost and performance modelling. This is done through Life Cycle Costing (LCC) and Thermal modelling which are visualized through Power BI linked to Excel and multifaceted simulations. The McDA is case studied with variances in the Spanish and Egyptian climates and economics to use as a balance in the cross-regional foundation model.
The results showed that GTGR systems save water meant for human consumption and decrease CO2 emissions, leading to substantial positive environmental impact. Economic performance remains extremely context reliant. All three systems in Spain are cost-efficient, while negative and positive Net Present Values (NPV) with reasonable payback periods are still usable for SGTS systems. This is not the case for Egypt, where only the SFIGR system is deemed economically feasible, while hydroponic and advanced systems are still financially non-viable. These results indicate that there are specific gaps in policy for the design of GTGR technologies that need to be filled in order to ensure that it is usable at scale.
4 The study acknowledges certain limitations, including reliance on secondary cost data, the application of generalized emission factors, and the exclusion of indirect co-benefits such as biodiversity
enhancement and social well-being. Nevertheless, the results provide critical insights into the trade- offs and synergies of GTGRs and offer evidence-based recommendations for policy and practice.
Ultimately, this research concludes that GTGRs can play a strategic role in sustainable urban water management and climate adaptation, directly contributing to the achievement of SDG 6 (Clean Water and Sanitation), SDG 11 (Sustainable Cities and Communities), and SDG 13 (Climate Action)
Keeping it Together: Assessing the Wellbeing of Project-Based Development Practitioners in Egypt
Full text linkThis thesis examines the wellbeing of project-based development practitioners in Egypt, revealing how systemic pressures—bureaucracy, job insecurity, and fragmented workloads—undermine both wellbeing and productivity. The study employed a mixed-approach, combining 10 in-depth interviews with subject matter experts and practitioners and 75 surveys with development practitioners in Egypt. Data revealed that while many practitioners are driven by purpose, structural challenges erode resilience and motivation over time. Social support networks and personal coping strategies help but cannot replace institutional protections. The study argues that wellbeing must shift from being treated as an individual concern to a structural responsibility. Reframing organizational models around human-centered logic and community resilience is essential. Safeguarding practitioner wellbeing is not just ethical—it is key to sustaining effective development work