Investigating the Aroma Chemistry of Dendrobium Stems (Chinese Name: Shihu)

People have consumed dried Dendrobium stems, known in China as Shihu, for thousands of years as food and traditional medicine. Shihu is valued for its potential health benefits and flavour attributes, and for this reason, it is well integrated into traditional Chinese cooking, and more recently, become a modern ingredient in nutraceutical drinks. Shihu contains a diverse range of volatile compounds and glucomannan polysaccharides. However, there are gaps in the knowledge of the compounds responsible for its aroma and their formation, and this thesis aims to investigate these important compounds through: 1) comprehensively investigating the aroma compounds of Dendrobium stems, focusing on 2) key aroma-active compounds, 3) assessing drying's impact on aroma formation and 4) evaluating flavour stability. Instrumental analysis was used to characterise and semi-quantify volatile aroma compounds, identify those responsible for the aroma, quantify flavour precursors, and evaluate aroma stability. Gas Chromatography-Mass Spectrometry (GC-MS) identified 21 aroma compounds in commercially available dried Shihu. Varying oven drying temperatures and durations impacted both the aroma compounds and moisture content (Chapter 3). Although the drying process resulted in a 28.45 % reduction in glucomannans, the research primarily focused on flavour. GC-O (Olfactometry) analysis with 13 panellists indicated nine aroma compounds were aroma-active in dried stems (including 1-octen-3-one and 4-oxoisophorone)(Chapter 4). Carotenoids, amino acids, and monosaccharides were quantified using three Liquid Chromatography techniques, linking precursor loss during drying to aroma-active compound formation (Chapter 5). Shelf life testing indicated no significant changes in aroma-active compounds during storage (20-30 °C for 12 weeks), but higher storage temperatures caused further precursor degradation (Chapter 6). Multivariate analysis indicated aroma compounds as markers of storage and temperature mismanagement. This research provides a mechanistic understanding of flavour generation during Shihu drying, applicable to other plants with similar chemistry. Awareness of important aroma compounds and their changes during storage has the potential to improve product quality and enhance the global popularity of Shihu

Magnetic Induction Tomography using Vector Spherical Harmonic Magnetic Fields and Quantum Sensing

The work explores the use of spherical harmonic magnetic vector fields in magnetic induction tomography, an eddy current based non-ionising imaging technique. It uses the spherical harmonic magnetic fields as primary excitor fields, creating orthogonal sensitivity matrices ensuring efficient and accurate image reconstruction using two different algorithms. The thesis further explores the phase of the eddy current induced secondary magnetic fields and seeks to use phase in image reconstruction. Lastly, the thesis seeks to measure the eddy current induced secondary magnetic fields from low conductivity materials using quantum sensors known as optically pumped magnetometers

Towards energy benchmarking in residential buildings in the Kingdom of Saudi Arabia

Countries worldwide are facing the challenges of improving energy efficiency and reducing carbon emissions to mitigate climate change, conserve resources, achieve energy security, and reap economic benefits. Over recent decades, the Kingdom of Saudi Arabia has experienced a rapid increase in domestic energy consumption. Notably, residential buildings have emerged as significant consumers, accounting for approximately 50% of the total electricity consumption within the building sector. This sustained expansion in energy demand raises concerns regarding environmental impact. Sustainability has recently become a fundamental issue in the Kingdom of Saudi Arabia (KSA), as one of the cornerstones of Saudi Vision 2030. One of the key initiatives under Vision 2030 is the Saudi Green Initiative, which aims to significantly reduce carbon emissions and achieve net zero emissions by 2060. To support the goals of the Saudi Green Initiative and promote sustainable growth, it is essential to develop effective strategies and tools for improving energy efficiency in residential buildings. One of the key challenges here is the lack of a national benchmark values that may help stakeholders to evaluate the energy consumption of their buildings. In response, this research attempts to develop a benchmarking framework tailored explicitly to the Saudi Arabian context and establish an energy benchmarking for residential buildings. The research is divided into five milestones. The first milestone involves a thorough review of energy consumption in the KSA, identifying factors contributing to energy demand, and reviewing the current energy benchmarking methods for buildings. This review provides a comprehensive insight into the energy consumption of residential buildings and identifies the most appropriate energy benchmarking methods, which can be adapted to the Saudi Arabian building context. The second research milestone involves collecting data from a representative sample of residential buildings in the Saudi Arabia. The third milestone involves improving the specifications of the representative sample buildings to comply with the Saudi Building Code (SBC) requirements. The fourth milestone concerns conducting statistical tests and analyses, which are necessary to ensure that the research is based on sound data and assumptions, contributing to the overall quality of the research. The last milestone involves developing energy benchmarks for villas and apartments in the KSA. The benchmark can contribute to improving building energy performance in the region. The benchmark provides insights into factors influencing energy use, enabling stakeholders to assess the energy efficiency of their buildings. The benchmark also educates the public about energy consumption patterns, influences building asset value, and aids policymakers in setting energy-efficiency standards and implementing incentives. The main findings reveal that applying the SBC-602/2018 requirements to the buildings can improve the energy consumption of villas and apartments by up to 19% and 40%, respectively. Moreover, the findings suggest that the normalised energy use intensity (EUInorm) benchmarks for villas and apartments that meet the SBC requirements in the Riyadh region are 60 kWh/m2/Yr and 98 kWh/m2/Yr, respectively. These benchmarking values were based on normalising the significant variables that affect energy consumption

Current and emergent allergens in food production systems

Of the global population, around 10% has a form of food allergy, with exposure to allergens in foods driving a variety of symptoms ranging from urticaria, localised swelling, discomfort, through to anaphylaxis. Incidence of food allergy has been identified to be increasing year on year, in relation to changes to the modern lifestyle leading to further diet diversity within in global populations, with greater exposure to and consumption of allergenic foods. Commonly, food allergens have been found to have current routes of exposure through unintended food allergen contamination in food production systems and the mislabelling of products, this resulting in frequent product recalls worldwide. The work presented in this thesis builds on current knowledge and explores emergent routes of food allergen exposure in the general population with a view of the expansion of ingredients used by the food industry and purchased online from digital food systems. Importantly, issues surrounding food allergy have the capacity to continue to increase over the next few decades due to the advent of circular agrifood economies and further incorporation of emerging foods with the potential for allergenicity to facilitate development of more sustainable food production systems. Three key areas became the focus of the current work 1) Emergent foods as sources of allergens in the human food chain, 2) Routes of food allergen transmission and exposure via new purchasing routes i.e. purchasing through online food systems and 3) The potential of allergen retention by food contact and storage materials as a possible route of allergenicity. Combined, our research sets the foundations for future work in these areas. The main findings of the current research identify that current and emergent food allergens are potentially increasing within modern food production systems and due to being unintended or undeclared have the capacity to pose a risk to consumers with food allergy. We first assessed, macro- and microalgal derived products as emergent food sources, as current drives to increase their incorporation into foods are gaining greater attention. We reported that edible algal species (microalgae: Arthrospira and Chlorella species; macroalgae: Chondrus crispus, Palmaria palmata and carrageenan isolated from several sources including Chondrus crispus, Eucheuma and Gigartina species), widely cultivated globally, are potential sources of emergent allergens in modern food production systems. Several allergenic components have been characterised, and these have been shown to induce allergic responses in humans. It was also reported that algal products have the potential to act as a vector of current food allergens including fish and shellfish. We next focused on a land growing crop, namely kiwifruit (Actinidia species) that is becoming more widely grown globally and incorporated into a spectrum of differing food items. The prevalence of a variety of food allergy reactions to kiwifruit has been identified globally (0-18 yrs: 0.1-0.2% to 60.0%; >18-96 yrs: 0.35% to 38.4%) and various proteinaceous kiwifruit allergens have been characterised namely actinidin/cysteine protease (Act d 1/Act c 1), thaumatin-like protein (Act d 2) and kiwellin (Act d 5/Act c 5). Food allergens from kiwifruit have been found to demonstrate cross-reactivity with other fruit and plant allergens and are often resistant to processing methods. In recent times, use of kiwifruit is increasing in processed products, including snacks, desserts, confectionary, condiments, beverages and food additives or functional ingredients (e.g. colours, flavours or coagulants), within food production systems, which could introduce the risk of its consumption as an unintended or unidentified food allergen. In our remaining chapters, we focused on routes of exposure from digital food systems and stability of food allergens in commercial washing processes. Online purchasing has increased in recent years, with recent reports describing that 60.8% of UK consumers are buying groceries online, and so we designed a series of experiments to capture transmission of current allergens in foods purchased via internet sources. We randomly selected 768 prepacked imported products purchased online and following extensive screening identified that 173 (22.5%) items provided precautionary allergen labelling and upon comparing food allergen information on pack and online, found that 36 (36.0%) transferred inconsistencies on pack to online pages and 15 (15.0%) were not consistent between information on pack and online. We also conducted a sub-analysis of the online purchased items including 77 products and assessed the unintended food allergen presence of milk and peanut using biochemical (ELISA) methodologies. Following analysis for milk and peanut via ELISA, 24 (31.2%) products were found to contain unintended food allergens, with 7 (29.2%) having levels that would recommend precautionary allergen labelling, though this was not present on these products to communicate this risk to consumers with food allergy. Clearly, this work points to significant avenues of allergen exposure via foods obtained through online sources and more work is needed in this area. Our final study explored an additional route of allergen exposure via retention of food allergens to common materials used to produce food contact and storage materials. Using sesame as a model allergen analyte, we designed and validated a novel methodology to assess impacts of soiling on food allergen retention on surfaces. After applying current commercial warewashing procedures it was found that, all studied materials (glass, lacquered metal and polypropylene plastic) retained varying amounts of food allergen soil, despite appearing visually clean, and warewashers can readily transfer food allergens to subsequent wash cycles and onto food contact surfaces in them. Analytical results obtained using an ELISA method were compared to action levels, identifying that minimum or maximum levels for products contained in all container types post-washing presented potential health risks to consumers with food allergy. In summary, the results of this thesis indicate the need for the further assessment of current and emergent sources of food allergens that are increasing within modern rapidly developing food production systems, their incidence of being unintended or undeclared and potential to pose a food safety risk to consumers with food allergy. In addition to this, more work is required to understand the food safety risks of emergent food products demonstrating allergenicity and methods to better manage and communicate the risks of both current and emergent food allergens

A flexible and participatory evaluation framework for historic villages in peri-urban areas in China: multi-dimensional value assessment for conservation and adaptive reuse

Historic villages in peri-urban areas hold significant value, including not only their conventional value as historic villages but also their unique value in urban-rural coordination, shaped by their transitional location. As key nodes where urban and rural influence converge, these villages are able to facilitate the exchange of urban-rural resources in terms of economy, ecology, culture, and infrastructure, driving urban-rural integration and mutual development. Conserving the natural and cultural environments of these villages can support urban-rural ecological sustainability and cultural diversity. Adaptive reuse of their physical fabric can also help incorporate them into urban-rural infrastructure and economic networks, therefore contributing to peri-urban governance while narrowing urban-rural gaps in living standards and fostering social stability. Given the pressures of urbanisation in many areas of the world, it is becoming increasingly urgent to establish an evaluation framework that helps identify the multi-dimensional values of such villages in order to guide conservation and adaptive reuse strategies. Existing evaluation frameworks are often rigid and expert-driven, designed for historic villages in general rather than those in peri-urban areas. As a result, they cannot account for the unique value of urban-rural coordination. Moreover, historic villages vary significantly in their individual characteristics, and different stakeholders may perceive their values differently. This research therefore proposes a new flexible and participatory evaluation framework for historic villages in peri-urban areas to better accommodate contextual variations and diverse stakeholder perspectives. The development process began with the creation of a preliminary evaluation framework, which incorporated multiple value dimensions and corresponding indicators. This framework was subsequently refined and validated using Structural Equation Modelling based on participant questionnaires obtained from China (n = 1013) and a case-study village in China (n = 319) to identify key multiple value dimensions and their corresponding indicators, assigning weightings accordingly. Then, two final frameworks were generated: one applicable at the national level in China and another tailored to a specific Chinese peri-urban case-study village. The findings reveal that these villages embody a wide range of values, including historic, cultural, artistic, research, educational, ecological, residential, economic, and urban-rural coordination values and therefore both frameworks specify the indicators to measure these multiple values. A comparative analysis of the weightings between the two frameworks demonstrates significant differences, underscoring the need for flexibility in evaluation. And a comparative analysis of the weightings assigned by different stakeholders also reveals significant differences, emphasising the importance of a participatory approach. Additionally, in-depth interviews (n = 19) conducted in the case village further enriched the contextual understanding of stakeholder perspectives and provided detailed support for the weightings and application of the evaluation framework. Based on these stakeholder perspectives and taking into account the significant differences in weightings, conservation and adaptive reuse strategies for the case village were successfully formulated, while also offering a methodological approach applicable to historic villages in peri-urban areas globally. Establishing such an evaluation framework contributes to sustainable urban expansion and regeneration while fostering public participation in conservation and reuse

ZEB1 signalling in endothelial cell heterogeneity

Endothelial cells (ECs) are at the core of vascular homeostasis, enabling angiogenesis, immune cell trafficking and barrier function. Zinc-finger E-box binding protein 1 (ZEB1) has recently emerged as a central regulator of EC plasticity, particularly through its roles in endothelial-to-mesenchymal transition (EndoMT) and vessel remodelling. Here, we test the hypothesis that ZEB1 expression dynamically modulates EC heterogeneity and specialisation during both developmental and pathological angiogenesis. Using siRNA knockdown (KD) and chromatin immunoprecipitation (ChIP)-seq in human umbilical vein endothelial cells (HUVECs), we show that ZEB1 broadly influences genes controlling cell adhesion, immune responses and tip-cell identity and cooperates with ETS and AP-1 transcription factors. Analyses of publicly available scRNA-seq datasets revealed ZEB1 enrichment in specialised EC subpopulations across multiple tissues, including venous-capillary ECs in the spleen, tip cells in the retina, tumour-associated ECs and floor ECs of the subcapsular sinus of the lymph node. Further analysis of myocardial infarction scRNA-seq data demonstrated that ZEB1 contributes to a partial EndoMT phenotype, wherein ECs retain some endothelial traits while acquiring mesenchymal characteristics. A text-mining approach further uncovered a proposed ZEB1 regulatory network in EndoMT. Finally, we demonstrate that adult induced ZEB1 knockout in adult retina ECs does not alter vascular area or number of ECs. Collectively, these findings position ZEB1 as a context-dependent modulator of ECs

“Take the hope away from me… take away that horrible turmoil” beyond disappointment: conceptualising maternal disenfranchised limerence through mothers' lived experiences

Background: ‘Gender disappointment’ (‘GD’) is an emerging maternal mental health phenomenon (Groenewald, 2016; Hendl and Browne, 2019; Saccio, 2025; Young et al., 2021). It is thought to be experienced by parents who have a child or children of one sex, but long for a child of the opposite sex (McMillan, 2012). It has been argued that ‘GD’ arises from embedded gender essentialist views and notions of the ‘good’ mother in the Global North (Groenewald, 2016; Hendl and Browne, 2019). Mothers who suffer from maternal ‘GD’ have been said to experience emotions ranging from a simple ‘disappointment’ to intense maternal anguish, including loss, guilt, and shame (Duckett, 2008; Groenewald, 2016; Monson and Donaghue, 2015; Young et al., 2021). It is notable that some of the most research into ‘GD’ is not informed by the voice of women with the experience, and this drove the study design (Hendl and Browne, 2019; Winter, 2021). Aims and objectives: This study aimed to develop a more informed conceptual understanding of the phenomenon known as ‘GD’ from the perspective of mothers. This was achieved by exploring the impact of maternal ‘GD’ on women’s emotions, well-being and help-seeking behaviours. Method: The author has lived experience of ‘GD’ and it was the loneliness, confusion, and pain of this experience that led to the design of a study that collected data from women who had experienced ‘GD’. Although not a prerequisite but of analytical significance, all the mothers who contacted the author to enquire about taking part in the study were mothers to only sons. Data was primarily collected via walking interviews at a location chosen by the women. A semi-structured interview schedule guided how the women were invited to share their journeys of maternal ‘GD’. The interviews were analysed by adapting the listening guide (LG) to include structured reflexive thematic analysis. The LG generated a case study for each woman, which included the mother’s journey in her own words, an I Poem, and the identification of two contrapuntal voices. This allowed for a nuanced exploration of the multiple and sometimes contradictory voices within each mother’s account. Following the case study, there was an amalgamation of the LG with reflexive thematic analysis, which enabled systematic thematic coding of the data set and the identification of shared patterns and themes. Findings: Analysis of the findings identified two overarching themes: i) hope, and ii) broken. Before the women became mothers, they had imagined themselves as mothers to a daughter and longed for a maternal relational experience they believed was only possible with a girl. This is understood through the lens of limerence, which is conceptualised as a state of obsession, idealisation and longing, thus allowing for deeper understanding of the mothers’ imagined daughters, which were the idealised figures of their longing and focus of their obsessive rumination. Consequently, this state of maternal limerence shaped the women’s investment in their long hoped-for daughter. The mother’s hope was what propelled them to seek out multiple pathways to attempt the conception of a female child. However, with the conception of each son, their distress at not having a daughter intensified, and the mothers’ hope became maladaptive, creating further complex layers of distress. The mothers’ imagined daughter was idealised and led to obsessive rumination, and as the daughter remained elusive, the mother's assumed future was ruptured, adding another layer of complexity to her experience. In contrast to the term “disappointment”, the women in this study experienced enduring grief and distress for their imagined daughter. This shaped their friendships, partner relationships, and decision-making processes; thus, “disappointment” fails to capture the depth of mothers’ experience. In moving towards acceptance, the women experienced a phase of action crisis; goal disengagement and finding new meaning in a different maternal path from the one they had expected. Significantly, the entirety of the mothers’ ‘GD’ experience was shrouded in disenfranchisement. These findings lead to the modelling of the journey as a negatively compounding and repeating cycle that was forward-moving, non-linear, and layered, comprising of seven dimensions: i) the imagined and hoped-for maternal experience, ii) preoccupation, iii) finding out the sex of the foetus, iv) loss, v) distress, vi) birth of child, vii) reaching “the line” and moving towards acceptance. The term ‘GD’ is therefore multidimensionally problematic, while the new term proposed here, maternal disenfranchised limerence (‘MDL’), more accurately reflects the complex and nuanced layers of distress experienced by the population in this study. This term and the accompanying conceptual model are provisional and positioned as a springboard for further exploration, offering a starting point for future research to refine and extend our understanding of this maternal phenomenon. Conclusion: This study asserts that ‘MDL’ is a maternal experience shrouded in disenfranchisement and characterised by complex layered distress driven by the paradox of hope. It contributes new insights to how ‘MDL’ is theorised by identifying the key roles played by hope, limerence, grief, and biographical disruption as central to this experience. A novel terminology and model are proposed as a springboard for better understanding of the ‘MDL’ experience, while illustrating the forward-moving but non-linear dimensions of the distress experienced by the mothers in this study. These findings have implications for the terminology being used, timing, and type of support offered to mothers’, as well as supporting the wider recognition of the phenomenon as a complex, valid, and multidimensionally distressing maternal experience

Enhancing ESG efforts through reporting: how do we minimize greenwashing? (focused on the SGX energy & utilities sector)

The integration of Environmental, Social, and Governance (ESG) criteria into corporate strategy has become increasingly crucial as stakeholders demand more sustainable and ethical business practices. However, the concurrent rise of greenwashing—where companies may overstate or inaccurately represent their ESG efforts to appear more environmentally friendly and socially responsible than they actually are—presents a notable challenge. Greenwashing not only undermines stakeholder trust but also jeopardizes the overall credibility of genuine sustainability efforts. This thesis aims to explore how enhanced reporting mechanisms can mitigate the incidence of greenwashing, thereby promoting authentic sustainability practices. A key component of this research involves understanding the public’s perception of corporate sustainability reporting. Public scrutiny has intensified as consumers, investors, and other stakeholders become more informed and vocal about corporate sustainability practices. This study seeks to incorporate the views of the public by examining how their trust in a company's reported ESG efforts influences their support and investment decisions. Through surveys and interviews, we will gather insights into how transparent and reliable the public perceives current ESG reporting to be, and what improvements they believe are necessary to reduce greenwashing. Through a comprehensive examination of current ESG reporting standards, regulatory frameworks, and best practices, this study seeks to explore how transparency and accountability can be enhanced through the adoption of unified reporting standards, mandatory disclosures, and the use of advanced technologies for traceability. By examining the roles of regulatory bodies and third-party verifications, this research will highlight effective strategies for minimizing greenwashing. The ultimate goal is to provide actionable recommendations that businesses and policymakers can implement to enhance the integrity of ESG reporting, ensuring that sustainability efforts are genuine and impactful, and fostering greater trust and engagement from the public

Towards organophosphonate-functionalised polyoxotungstate-based metal–organic frameworks

Polyoxometalates (POMs) are a group of anionic soluble metal-oxide clusters containing d-block elements in high oxidation states. These compounds are highly valued for their wide range of electrochemical, photochemical, and catalytic properties, due to their remarkable flexibility in tuning both composition and structure. One common method of modifying POM is by connecting the electron-withdrawing organophosphonate groups to the active sites of metal oxides. When POMs are functionalised with organophosphorus compounds, it is possible to adjust their electronic structure and photochemical activity based on the electronic properties of the attached organic moieties. However, the high solubility of POMs restricts their application in sensors, electrodes, and catalysis regions. By linking POMs in a repeating pattern through bridging organic linkers, insoluble metal-organic frameworks (MOFs) can be formed. These MOFs retain the structural features of the parent molecular POMs and commonly enhance electrochemical activity. Herein, we report the synthesis of a new hybrid POM, K6[P2W17O57(PO5H9C13)2] using a biphenyl organophosphonate ligand. The hybrid POMs were characterised by FTIR, NMR and ESI-MS. A series of multi-phenyl organophosphonate functionalised POM were synthesised, and all hybrid POMs were applied to construct POM-based MOFs (POMOFs). The structures of resulting POMOFs were analysed by PXRD. Hybridisation with long-chain organophosphonate groups is expected to stabilise electron-conducting pathways of MOFs, potentially overcoming limitations such as its low conductivity and poor electrochemical durability. The design of these new POMOFs offers a promising strategy for the development of advanced materials for various battery systems