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Exploring the experiences and perspectives of Saudi mothers in interaction with their primary school children’s autonomy and motivation within COVID learning contexts
Get PDFThe COVID-19 pandemic impacted families worldwide; those in Saudi Arabia were among them. This period presented mothers with unique opportunities and challenges, including the chance to “get to know” their children better and explore strategies to promote autonomy and motivation during the primary school years. Despite Saudi Arabia’s ongoing development and implementation of Vision 2030 – i.e., a dynamic strategy that supports lifelong learning and individual potential – there is a notable lack of studies that focus on the role of the family and the importance of autonomy for children in remote learning. However, remote learning is a relatively new experience for Saudi society, especially for primary-aged children. This research aligns with the concept of “actualising tendency”, pioneered by Carl Rogers in 1961, which emphasises personal autonomy as an intrinsic motivation that drives individuals towards excellence. Understanding how Saudi families navigated these challenges during remote learning is crucial for children and future educational development and alignment with the goals of Vision 2030. This research is divided into two studies. The first study solely focuses on mothers with a background in Saudi Arabia; the second study concentrates on mothers with a multicultural “KSA-UK” background.
In order to explore the mothers’ in-depth subjective experience with remote learning, an interpretative phenomenological analysis (IPA) is used to analyse the interview data and answer the following questions: 1. What experiences, challenges and strategies are encountered by Saudi mothers, with exposure to only a single culture, when their children interacted with remote learning? 2. What are the influential factors and strategies that Saudi mothers perceived and experienced when their children interacted with remote learning and multicultural contexts? The findings revealed a complex interplay of culture and mothers’ experiences, which seem to shape their self-concept, defined in this study as a person’s perception and comprehension of themselves, including their beliefs, values, abilities and traits (Ismail & Tekke, 2015).
Furthermore, remote learning plays a role in collaboration between mothers and their children, allowing them to experience autonomy and self-determination. Mothers acknowledge their children’s ability to adapt to challenges in remote learning contexts, which seems to contribute to increasing child autonomy. In both studies, mothers used rewards and punishment as motivational methods, which presents tensions with the person-centred approach (PCA) and self-determination theory (SDT), as these approaches emphasise intrinsic motivation and the importance of fostering autonomy rather than relying on external controls such as rewards and punishments. The second study reveals how the mother’s experience abroad possibly influences her personal values and attitudes. Moving away may have disrupted the influence of others, allowing mothers more freedom to develop their parenting style. The findings are discussed in relation to previous research and relevant theories. The study also considers the implications of the findings for Saudi society and families, including Saudi mothers who study abroad, remote learning and childhood education
Bioenergy with carbon capture and storage and shale gas: a comparative discourse analysis of two energy technologies in the context of the UK’s net zero transition
Get PDFContributing to the fields of energy and environmental policy studies, using Maarten Hajer’s (1995) framework of discourse analysis as its main analytical and methodological approach, this thesis focuses on two energy technologies, bioenergy with carbon capture and storage (BECCS) and hydraulic fracturing. This thesis expands on the existing knowledge and body of research in this area, by providing a comparative discourse analysis of the two energy technologies in the unique context of the UK’s net zero transition.
Approaching energy technologies as inherently socio-technical systems, the choice of comparing shale gas and BECCS is justified in several ways. Both past and present energy policies described shale gas and BECCS as being able to contribute to decarbonisation to various degrees, being described as a lower carbon and a net zero carbon energy technology respectively. Although utilising different processes, one of storage and the other of extraction, the energy technologies share the use of underground space. Their low-carbon credentials are also points of contestation. Neither of the technologies is being deployed at a commercial scale in the UK, with shale gas having only been in exploratory stages and BECCS being trialled. Additionally, they share a tension between the substantial roles that the two energy technologies were envisioned to play in the UK’s energy mix at different points in time and the current lack of realisation of these roles.
In 2019, the UK Government announced a legally binding target to bring all greenhouse gas emissions to net zero by 2050. Using purposive and snowball sampling, I have conducted 31 semi-structured interviews with key actors, between 2020 and 2021, during a time when the net zero transition was well underway. Working with the assumption that language is not a neutral transmitter and that the world is shaped by the language we use to describe it, this thesis used discourse analysis to answer how key actors make sense of BECCS and shale gas in the context of the net zero transition. More specifically, the thesis focused on how the participants’ understanding of shale gas and BECCS reflected in the language that they used to describe the energy technologies and the energy transition itself. I have analysed this using the discourse analytical concepts of ‘storyline’ and ‘discourse coalition’ and have then subsequently categorised the different visions of the net zero transition as presented in these discourse coalitions.
By doing this I demonstrated that there is not a clear shared understanding of the role and potential of BECCS among key actors and that there is a wide range of views on the functionality, scalability, and sustainability of the technology. In contrast to previous findings, this research also showed that in the context of net zero transition, the shale gas discourse is less polarised. Instead of the expected two discourse coalitions, pro- and anti- shale gas, this discourse is divided into three, neither of which is distinctly pro-shale gas. Rather, the shale gas discourse coalitions differ in the way they make sense of the absence or failure of shale gas development in the UK. The thesis also demonstrated that it seems to be very difficult for key actors to make sense of and conceptualise future visions of both BECCS and shale gas without referencing the net zero transition and that there are three types of visions of the net zero transition among key actors. These visions vary widely in the way they understand the potential and role of the net zero transition, and most importantly in the way they view the relationship between shale gas, BECCS and the transition. These insights highlight the contentious nature of the energy debate and the discursive struggles within the net zero transition, which could ultimately shape the way in which the net zero transition develops and are therefore important to study and to pay attention to at this point
Biomass densification for minimal drying energy and optimised pellet quality
Get PDFBiomass power generation has been gaining increasing importance globally in recent years to provide renewable energy and combat climate change. However, several constraints have limited the expansion of biomass power generation, and in particular, the use of alternative biomass feedstocks to wood. The major challenges of the industry include the high drying energy of biomass, the need for biomass densification and the variability in the properties of biomass. This thesis addresses several of the major challenges of the industry through the study of the properties of alternative biomass feedstocks, the development of a new novel low-energy biomass drying process, the in-depth investigation of biomass pelleting and pellet milling behaviour, and the use of Life Cycle Analysis (LCA) to study the environmental benefits of biomass power generation from a system perspective.
The results presented have provided new insights and addressed multiple gaps in knowledge in the existing literature. In addition, the new knowledge presented is valuable for the industry to improve the understanding of unconventional biomass feedstocks and industrial processes, and the new tools and methods developed can be used by industry to deliver substantial environmental and economic benefits.
The characterisation of several conventional and alternative biomass feedstocks was conducted. The characteristics of cardboard materials, including char morphology, burnout performance and particle shape change during combustion, were studied in detail and a new method of using thermogravimetric analysis to measure calcium carbonate content in cardboard was developed. In general, cardboard chars are more porous and thin-walled than eucalyptus chars, indicating a better char burnout performance. The challenges of using cardboard for power generation applications would include potential handling difficulties, a low calorific value and high ash content.
The feasibility of a new novel combined pasteurisation and natural drying process was established using a set of experiments with miscanthus and spent grains, which can dramatically decrease the drying energy of biomass. Biomass briquettes were pasteurised and monitored over a storge period of up to nine weeks. Substantial decrease of moisture content was achieved by natural drying, while optimised pasteurisation strategies can provide effective fungal growth suppression during the storage period. It was also found that microwave pasteurisation can achieve similar or better levels of fungal growth suppression with shorter processing times compared to conventional oven pasteurisation.
The pelleting and pellet milling behaviour of sugarcane straws was investigated and new parameters were developed to quantify the pelleting process. The influence of various factors on pelleting and pellet milling was investigated, including moisture content, particle size and harvest season. It was found that pelleting failure was more likely to occur at low moisture contents, at fine particle sizes, and with the dry season sample.
Lastly, an LCA study of a biomass power generation system using bagasse from the United States to generate power in the United Kingdom was conducted. It was found that for the system studied, the overall carbon footprint of the electricity generated is 81.6 g CO2/kWh. The main opportunities of reducing carbon emissions are the electricity use at the pellet plant and shipping between the origin port and the destination port. It was also concluded that substantial benefits in terms of global warming potential could be achieved by the system studied, particularly if carbon capture and storage is also integrated
Supramolecular and Materials Applications of Tetrazines
No full textTetrazines are a functional group with emerging applications in materials. The ability to undergo the inverse electron-demand Diels-Alder (IEDDA) reaction with alkenes and alkynes has emerged as a leading click reaction. This makes tetrazine a perfect choice for post-assembly modification (PAM) on metal organic cages (MOCs), and rotaxanes. In order to form new supramolecular structures such as MOCs it is often needed to repeat the process of ligand design and synthesis however with the tetrazine moiety as part of the backbone the structures can be modified with an array of alkenes/alkynes allowing tailored modification of the molecules. Throughout this thesis tetrazines were synthesised with PAM in mind.
Chapter two highlights the methodologies used, specifically NMR spectroscopy, mass spectrometry, SCXRD, and CV with a specific focus on the investigation of supramolecular structures as a combination is needed to confirm product formation.
Chapter three investigates the assembly of tetrazine edged MOCs using Pd(II) metal nodes to form a tetrahedral Pd4L8 assembly. The IEDDA reaction of the cage with an array of alkenes including norbornadiene, norbornene derivatives and cyclopentene was investigated with a focus on the structural transformations to Pd2L4 lanterns that take place by the introduction of flexibility in the rigid ligand. The process of assembly and PAM was followed by NMR spectroscopy, ESI-MS and SCXRD. The PAM led to a reduction in the angle between ligand vectors from an average of 63.1° to 7.2°. Single crystals of dihydropyridazine intermediates showed preferential formation of a sole isomer with maximum hydrogen bonding and high symmetry which was investigated. To the best of my knowledge the PAM with alkenes other than norbornadiene, had not been studied in the literature. The sequential oxidation of the dihydropyridazine intermediates via chemical oxidant was attempted and showed secondary structural changes to Pd4L8 and Pd3L6 topologies, as ligand planarity returned. This demonstrated that simple ligand alterations have distinct consequences on structure. The assembly of similar Pt(II) MOCs was also attempted and compared with the Pd(II) analogue.
Chapter four focuses on the formation of tetrazine-based rotaxanes using dimethoxypillar[5]arene as a macrocycle. Rotaxanes with tetrazines as components of the axle are sparse in the literature. Much work has been done on controlling the reactivity of tetrazines towards the IEDDA through chemical effects however the rotaxane provides the opportunity to affect the reactivity through a mechanical bond. Therefore a variety of tetrazine incorporating axles were synthesised, both with aryl and alkyl substituents. Tetrazines substituted with pyridines at the 3 and 6 positions showed poor stoppering, and limited association with both pillar[5] and pillar[6]arene macrocyles. Tetrazines with alkyl imidazole substituents showed improved association with dimethoxypillar[5]arene macrocycle, mass spectrometry suggested the formation of [2] and [3]rotaxanes. The formation of rotaxanes was alkyl chain dependent with the pillar[5]arene requiring an alkyl chain more than two carbons long to induce association.The focus in Chapter five shifts to investigate the role substituted tetrazines play as redox mediators in lithium sulfur batteries. Lithium battery technology is looking beyond lithium-ion batteries as the theoretical potential is reached. Tetrazine can be reversibly reduced to the radical anion which made it a potential candidate as a redox shuttle in Li-sulfur batteries, an emerging next generation batteries technology. A library of tetrazines were screened with reduction potentials in the correct position to help reduce the polysulfide, acting as redox shuttles. A couple of the tetrazines appeared to be acting as a redox catalyst shown via cyclic voltammetry and showed improved performance during cell cycling. Steps to understand the mechanism were taken however this currently continues to remain unknown
Design, Synthesis, and Evaluation of New P2Y2 Receptor Antagonists and Fluorescent Ligands
No full textThe P2Y2 receptor (P2Y2R) is an exciting therapeutic target for numerous diseases including atherosclerosis, idiopathic pulmonary fibrosis, and cancer. Despite this, there are a limited number of receptor antagonists available, none of which are clinically viable. The highest affinity P2Y2R antagonists detailed are AR-C118925 and its thiazole-based analogues, for which physiochemical properties remain a barrier for future drug development.
The work presented in this project details the design, synthesis, and evaluation of new chemotype P2Y2R antagonists and fluorescent ligands, which provide scope for future drug development projects to depart from ARC118925 and its analogues. The new chemotype P2Y2R antagonists and fluorescent ligands retained micromolar affinity for the receptor, despite the absence of the tricyclic ring system and thiouracil, with the presence of a terminal acidic group on the thiazole substituent being crucial for P2Y2R activity. The fluorescent ligand 4.09 (pKd = 5.24 ± 0.04, n = 5), which appears to bind to the P2Y2R on the intracellular side of the plasma membrane, offers exciting opportunities to target this difficult to drug receptor with new modalities that could overcome existing limitations in developing P2Y2R antagonists
Interactions with Valuescapes: applications of extra-sensory values in everyday coffee personalization
Get PDFPersonalization of consumables is increasingly grounded on extra-sensory as well as sensory qualities. Using the everyday example of coffee, this thesis addresses the challenge of creating a values-orientated personalization paradigm that maintains the descriptive and predictive capabilities of sensory product-preference alignment seen in mass market approaches, while also eliciting the extra-sensory qualities more likely evaluated by the consumer end-user as ‘personal’. This paradigm is referred to as the ‘Valuescape’; a theoretical, structural conception of the socio-technical world in which values themselves become objects for interaction.
This work begins by presenting a shared problem of values-orientated personalization in industry, human-computer interaction (HCI), and digital society (Chapter 1:); a literature review framing approaches to coffee personalization in terms of industry norms, theories of social value, and interaction value (Chapter 2:); and a methodology establishing a three-part approach to asserting, probing, and provoking values-orientated interactions, enabling a thematic analysis of participant retrospection on interactions with Valuescape(s). Designs for Valuescape(s) are presented here, along with ‘CoffeeWizard’ – a framework for producing ‘personal valuescapes’ used in two of three empirical studies (Chapter 3:). In ‘Contingencies for Valued Interaction’, a timeline is used provoke the elaborations of hospitality workers on how they maintained preferred practices during the Covid-19 pandemic (Chapter 4:). In ‘Interactions with CoffeeWizard’, the framework for generating personal valuescapes takes the form of a coffee selection box, surveying user preferences, provoking product choice, and eliciting retrospection on ‘personal value-footprints’ (Chapter 5:). In ‘Building Valuescape’, novel graphs serve as the primary provocation to personal preference selection in speculative enactments with a prototype recommender interface (Chapter 6:).
Four top level modes of interaction are found and set out as ‘substantiation’, ‘practical application’, ‘evocative remembrance’, and ‘speculative co-design’. Personal valuescapes as constructions that provoke are delineated from Valuescape as a social structure that can be probed, with instances of interaction across studies contributing to four distinct ‘archetypes’ of Valuescape and associated implications for their use between consumers and corporate value experts as mechanisms, agents, and of democratising value agendas (Chapter 7:). Finally, limitations are discussed, informing recommendations for revised study protocols and future works (Chapter 8:)
Materials and machine techniques for automated repair of bituminous pavements
Get PDFResearch has been conducted to evaluate the feasibility of automating crack and pothole repairs in bituminous pavements within a laboratory setting. Traditional manual methods, while effective, are labour-intensive, time-consuming, and prone to variability, underscoring the urgent need for automation to enhance efficiency, precision, scalability, and safety. To address these limitations, machines requiring minimal human input were developed alongside asphalt mixtures tailored for automated applications. A comprehensive review identified 3D printing as an optimal, economical, and user-friendly technology for creating repair machines. Accordingly, a RepRap 3D printer was modified for repair tasks, with parameters such as filling speed and extrusion temperature systematically optimised to improve repair quality.
The research investigated the effects of bitumen type, crack width, irregularity, and hot bitumen flow on the performance of automated crack filling. Results revealed that bitumen flow rate, filling speed, and crack geometry significantly affect fill quality. Specifically, lower temperatures resulted in incomplete filling, while higher temperatures and suboptimal speeds led to overfilling. These findings highlight the critical importance of precisely controlling temperature, flow rate, and filling speed to optimise performance in future fully autonomous robotic systems.
A novel digital methodology, developed using physics engine software with aggregate geometry as a key input, enabled the design of asphalt mixtures tailored to performance requirements such as extrudability, stability, and flow. Validated through independent tests at the Czech Technical University in Prague, the method achieved 78% accuracy in predicting the properties of real mixtures with highly variable compositions. It offers a reliable, performance-based alternative to traditional trial-and-error methods and lays the groundwork for automating asphalt design in road repair operations.
The digital method was further applied to produce asphalt repair cartridges for a screw-extrusion-based automated pothole filling machine, which achieved 86% of the rutting resistance observed in manual techniques. In a transitional phase, this machine could be mounted on trucks for in-situ pothole repairs, providing an immediate and cost-effective solution for practitioners. Over the long term, it has the potential to evolve into advanced, fully autonomous robotic systems, paving the way for more efficient, self-operating road maintenance
Three-dimensional inkjet printing of electrically active materials
Get PDFAdditive Manufacturing (AM) for electronics (AME) offers the capability for a new generation of devices, with digitised customisation, remarkable design freedom, and low wastage. To achieve this, AM must enable excellent material properties, high resolution, multi-material processing, and scalability to attain industrial relevance. Inkjet printing (IJP) is one of the most mature technologies capable of such material properties and resolution, originating from graphical printing but now with several decades of research into functional materials behind it. IJP excels at multi-material processing and scalability, but major criticisms are the high anisotropy and inability to print truly 3D geometries, generally settling on 2.5D heterostructures instead.
This work reports on a new finding that the anisotropy of conductivity in silver nanoparticle inks has been overestimated, and that it is mostly independent of the ink composition. Further, four polymer inks were investigated to pair with the silver ink as support and for high-quality dielectric contrast. Additionally, a novel method which requires no custom hardware – “Off the Grid” – was developed to remove aliasing which artificially decreases drop placement fidelity. This increases the accuracy of shape outlines and provides methods to control layer topology and negative space.
This work was built upon to create 3D structures with uniquely complex geometries compared to previous IJP efforts, with single-drop-wide micropillars printed ≤ 4 mm high. After investigating the growth mechanism of the pillars, it was shown that they can lean without support, which enables the printing of helices and strut-based lattices. Finally, multimaterial prints are demonstrated with anisotropic silver elements within a dielectric matrix, which allows for easy control of the macro dielectric properties. Overall, this work pushes the boundaries of achievable geometries within AME and opens the potential for a wide range of functional devices to be inkjet-printed
Impact of CO2 permeation on inter–layers and reservoir caprock sealing efficiency
No full textCarbon capture and storage (CCS) is expected to play a vital role in achieving greenhouse gas reduction targets. The key stage of the CCS system is storing the carbon dioxide (CO2) into geological formations safely for millions of years. This cannot be achieved without comprehensive investigation of the caprock/seal integrity. The need to find sufficient capacity for geological CO2 storage to meet demand means less than ideal, heterogeneous reservoirs need to be considered. Many such reservoirs are apparently compartmentalised by thin inter–layers, and have complex caprock structures, including, faults, fractures, chimney–like structures, heterogeneity in thicknesses, and petrophysical properties. The literature surveyed indicated that the subsequent evolution of the caprock and reservoir following exposure to scCO2 involves a complex coupling of geomechanics, geochemistry, and mass transport processes over different lengths and time scales. The combination of all three factors together is rarely considered but is required to properly test the feasibility of the storage site. Further, significant research gaps were identified regarding the effects of complicated, intricate processes affecting shale inter–layer (or seal) integrity under realistic reservoir conditions. This thesis investigates the impact of shale inter–layers of thicknesses below seismic resolution that are generally neglected in plume migration simulations, but have been shown here to be important. Only simulations of plume migration that include coupling of all three of mass transport, geo–chemical and geo–mechanical processes together provide proper prediction of the barrier efficiency of relatively thin shale inter–layers in ‘Sleipner–like field’. Furthermore, the research investigated the importance of intricate feedback interactions, occurring in systems with complex seal and reservoir geologies, for controlling the overall plume migration behaviour in a model of a ‘Bunter–like’ storage site. This was done by comprehensive numerical simulation of various scenarios using 3D static models based on geological structures found in the Sleipner and Bunter fields and then preforming fully coupled flow–mechanical–chemical simulations using compositional simulator CMG–GEM software. The simulation results showed a series of feedback inter–actions between these three process types. These have been studied in detail, and, for example, lead to the unexpectedly higher barrier efficiency of thin inter–layers compared to slightly thicker inter–layers.
The results show that capillary breakthrough pressure, diffusion processes and the re–activation of natural fractures played a vital role in enhancing the migration of the CO2 plume via the thicker shale inter–layers towards the overburden. In addition, the findings indicated that the use of an oversimplified caprock model, which assumed only a single impermeable caprock layer and no CO2 leakage, would give rise to misleading conclusions about CO2 plume migration. When comparing CO2 plume migration between scenarios with either a multi–layered, variegated caprock, or just a single caprock, it was found that 20% of the injected CO2 leaked in the former, whereas no leakage was observed through the latter. The presence of a chimney–like structure, within a multi–layered caprock, facilitated lateral CO2 plume movement due to advection forces, unlike with a single, uniform caprock. Also, in a scenario with both shale inter–layers in the reservoir, and a chimney in the caprock, while, during the post–injection period, fracture re–activation was observed in the upper inter–layer near the chimney zone in both multi–layer and single caprocks, this occurred significantly earlier for the former compared to the latter. The presence of a chimney in the caprock led to significant localised downward CO2–rich brine fingering in the reservoir below, caused by gravitational instability and heterogeneity in petrophysical properties, due to leakage through the chimney. Larger fault re–activation was noted in multi–layered caprocks, when compared to a single caprock. Calcite mineral changes significantly influenced caprock porosity across all Cases considered, while halite changes within sub–layers varied between multi–layer and single caprocks. Over the 1000–year simulation period, most of the injected CO2 remained in the supercritical phase, followed by dissolution trapping of the CO2, hysteresis trapping, and finally, mineralisation. The long–term spreading behaviour of the leaked fraction of the plume is very different for multi–layer, as opposed to a single layer, caprocks
Antibiotic and Antimicrobial Metal Resistance in Escherichia coli from Livestock
No full textAntibiotic resistance is a global threat, with misuse and overuse of antibiotics as key drivers. Metal exposure has also been hypothesized to promote bacterial resistance through co-selection mechanisms. This study comprehensively investigated the impact of metal exposure on multidrug resistance using Escherichia coli isolates from livestock and wastewater.
Zinc supplementation in animal feed significantly increased zinc tolerance in E. coli isolates but no correlation between zinc treatment and multi-drug resistance prevalence was observed in a large-scale analysis of isolates from a pig feed trial. Notably, wastewater E. coli isolates exhibited a unique zinc resistance phenotype, inducible by low zinc concentrations and reversible upon zinc removal. Whole-genome sequencing of mercury resistant E. coli isolates from pig feed trials identified a novel Tn21-like transposon carrying nine resistance genes, revealing the genetic diversity and integrative potential of the Tn21 family. Additionally, the Copper Homeostasis and Silver Resistance Island (CHaSRI) mobile genetic elements were also identified from pig feed trials provided new insights into the horizontal transfer of metal resistance genes, emphasizing the impact of high local accumulations of metal ions on environmental microorganisms, animals, and humans
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