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Advancing understanding of the genetic basis of grain protein content in wheat through hyperspectral imaging and genomics
No full textGrain protein content (GPC) determines the rheological properties of bread wheat and is a vital nutritional trait because wheat accounts for ~20% of global caloric and protein intake. The genetic basis of GPC is historically associated with senescence and post-anthesis nitrogen (N) remobilisation from source to sink tissues through Gpc-B1 alleles. Recent research has suggested that vascular architecture can also affect GPC variation through the activity of a HOMOEOBOX DOMAIN-2 (HB-2) gene. My thesis comprehensively investigated the physiological and biological mechanisms underpinning GPC and N remobilisation in wheat lines that contain variant HB-2 alleles. I investigated the newly identified HB-2 alleles for their effect on grain yield and N-use efficiency in the spring wheat Cadenza background using glasshouse experiments. These experiments showed that HB-2 improved GPC without a yield trade-off, particularly in response to N limitation, which is attributable to enhanced sink strength facilitated by higher HB-2 expression during the early stages of inflorescence development. Analyses of the grain transcriptome in these lines under two levels of N suggested that protein storage-related processes respond to N availability difference during early- to mid-filling. Moreover, a positive correlation was detected between co-upregulated gene networks and GPC at the early-filling stage. Notably, the grain transcriptome of HB-2 mutants grown under limited N responded similarly to wild-type supplied with optimum N, indicating HB-2 could be a promising candidate for improving N-use efficiency of wheat; results shown here support further investigation of HB-2 alleles in backgrounds of elite cultivars and different environments. To complement my analysis of the HB-2 alleles, I investigated the A. E. Watkins global wheat landrace collection to identify novel genetic factors associated with GPC that may have been lost during modern breeding. I developed a single grain-based protein prediction model using hyperspectral imaging and machine learning. I analysed single wheat grains from two field trials in the UK at different sites/years. The single grains were phenotyped for GPC, GPC heterogeneity (the variation among single grains within a genotype), grain weight, and grain morphological features such as length, width and area. These phenotypes were associated with genetic variation in the Watkins panel using ~90 million single nucleotide polymorphisms through genome-wide association analyses. This work identified promising loci on chromosomes 6A, 6D and 7D of the Watkins landraces that showed significant association with GPC. These loci may present an opportunity to incorporate novel GPC-associated genetic variation into modern wheat varieties. Moreover, my results showed that GPC heterogeneity is a heritable trait with a stable locus at chromosome 6A contributing ~17% of the 25% heritable variance. My thesis provides genetic insights for improving GPC in wheat without compromising yield, including the identification of molecular processes that are associated with higher protein content. It also provides valuable technical advances for screening large populations that will help breeding programs accelerate the evaluation of GPC while identifying the importance of poorly understood traits such as grain protein heterogeneity
Rules, cooperation and punishment: rules in repeated public goods games
Get PDFThe tendency for people to follow arbitrary rules, even when costly, has been repeatedly demonstrated in experimental economics. Rule following has been proposed as a key reason why humans are capable of sustaining long-term cooperation. However, the mechanisms by which rule-following leads to cooperation are not well understood. This paper aims to shed light on how rules govern cooperation by studying a repeated public goods game with an explicit rule prescribing contributions go to the shared public good, compared to when the rule is absent. Moreover, treatments with peer punishment are also considered, as punishment has been proposed as a crucial element for long-run cooperation. The motivation is that such a design will be able to shed light on how a rule governs behaviour in repeated interactions: for example, how social expectations are shaped by rules, how individuals of different rule-following propensities change their behaviour in the presence of one another, and how the efficacy of punishment is altered when a rule is present
Testing for transparency: designing privacy-informing systems for young people
Get PDFPrivacy notices are presented to the users of online services, usually upon entering a website and they are the predominant tool for informing them about information privacy practices. Often, a users reading and signing of the privacy notice is the condition to their entry to a website. The content of the notice is used to protect the services interests and demonstrate that users have been made aware of its privacy practices. In the case of sites and other online services aimed toward children, websites cannot acquire their consent. However, it is still vital and often legally required that the website present the information in a way that they will understand.
This PhD seeks to assess the presentation of child facing privacy notices and other privacy informing mechanisms (practice presentations) online. It does so by first providing a review of the landscape of child-facing practice presentations in the present day. Then, through a series of engagements with young people and the designers of service interfaces, it imagines what the future of practice presentations might look like, and how this project can help to design that future
Woman, life, freedom: reconfiguring feminist borders in Iranian feminist protest: how does the 2022 woman, life, freedom movement reflect an evolving transnational feminist praxis in Iran?
Get PDFThis study investigates how the 2022 Woman, Life, Freedom movement in Iran embodies an evolving transnational feminist praxis, reflecting the intersection of global feminist discourses and locally rooted feminist identities. Grounded in transnational feminism, the research challenges conventional binaries between ‘local’ and ‘global’ feminism, particularly as constructed within postmodernist feminist paradigms. Employing frame alignment theory, it conducts a critical discourse analysis of the activism and public narratives of six prominent Iranian feminist figures. By doing so, the study highlights how feminist actors in Iran strategically engage with global feminist currents while navigating the constraints of a theocratic and authoritarian regime. The research reveals the emergence of a hybrid feminist praxis, shaped by transnationalism, global rights discourse, and a shared emphasis on bodily autonomy, creating new spaces of connection and solidarity across borders. In contributing to debates within feminist movement studies, this study underscores the fluidity and adaptability of feminist expression in politically repressive contexts and calls for a re-examination of how feminist movements are framed across borders. Ultimately, it positions the Woman, Life, Freedom movement not merely as a national moment of resistance but as a critical site of global feminist re-articulation
Understanding mesocotyl elongation in rice
No full textMesocotyl elongation is a valuable trait for successful germination and establishment of direct-seeded rice (DSR) because it enables seedlings to germinate from deeper sowing depths and produce vigorous early growth in unfavourable field conditions. In this thesis, the systematic genetic and molecular dissection of the mesocotyl elongation trait in Oryza sativa is outlined with a focus on the Cellulose Synthase A (CesA) gene family, and in particular OsCesA3, which is revealed as a promising and novel regulator of the trait. A detailed in-silico screening of the CesA gene family revealed gene structures that were heterogeneous, evolutionarily conserved, and rich in hormone-responsive elements within the promoter regions, especially for gibberellins and auxin—two hormones that are known to cause elongation growth. OsCesA3 was identified as an important candidate gene within the family based on its developmental expression pattern, association with mesocotyl length in a GWAS, and regulatory responsiveness.
Functional determination by overexpression and CRISPR/Cas9-mediated gene editing also support the role of OsCesA3 in controlling mesocotyl elongation. Overexpression lines exhibited increased mesocotyl length and increased cellulose deposition, and gene-edited lines exhibited reduced elongation and abnormal cell wall sugar composition with decreased cellulose and increased hemicellulose. These results suggest OsCesA3 as a crucial regulator of primary cell wall biosynthesis and elongation-specific growth in the mesocotyl. Notably, cross-species complementation in Arabidopsis thaliana rescued the short hypocotyl phenotype of the prc1-1 mutant, confirming functional conservation of CesA3 in monocots and dicots.
The understanding of the mesocotyl elongation process was also facilitated by transcriptomic analysis, revealing differential expression of cell wall modifying enzymes, hormone signalling genes, and novel transcription factors in long and short mesocotyl genotypes. Expansin, XTH, and pectin esterase genes were overexpressed in long mesocotyl lines, and regulatory factors such as ZOS4-14 (C2H2 zinc finger protein), MYB-like, and AP2 domain transcription factors were chief suspects for upstream regulation of elongation pathways. Interaction among gibberellin, auxin, and cytokinin hormone pathways was also evident and suggestive of the coordination and complexity of hormonal regulation of elongation. Together, these findings increase our understanding of the genetic and molecular factors controlling mesocotyl elongation and provide approaches to improve DSR practices
Investigating Knowledge and Use of Technical Vocabulary in Saudi Engineering Masters’ Dissertations: A Corpus-based Study
Get PDFThis thesis explores technical vocabulary in engineering masters’ dissertations, an academic genre that has received less attention compared to textbooks, course materials, and research articles. It addresses this gap through three linked studies, employing both quantitative and qualitative methods to investigate the knowledge and the usage of technical vocabulary in engineering masters’ dissertations written by Saudi students. The first study examines the lexical profile and vocabulary load of a specialised corpus, consisting of 1,322,437 words compiled from such dissertations written by Saudi students at King Abdul-Aziz University. The findings showed that 4,000- and 7,000-word families, along with four supplementary lists and an engineering-specific word list, were necessary to achieve a minimal 95% and optimal 98% comprehension in engineering master’s discourse. This highlights the lexically demanding nature of the Engineering Masters’ Dissertation Corpus (EMDC).
The second study employs a combination of corpus-based and semantic approaches to identify and analyse single-word and multiword units (MWUs) of technical vocabulary in EMDC. The findings showed that 930 single-word items of engineering technical vocabulary (ETV) were identified, which covered 19.92% of tokens in the EMDC. The study found that 61.29% of the ETV (570 words) was from high-frequency vocabulary bands e.g., bus, coolant, absorption, 25.49% (237 words) from mid-frequency bands e.g., aluminium, altitude, antennas, and 4.12% (38 words) from low-frequency bands e.g., brine, axial, photovoltaic. Additionally, 2.0% (19 words) were from supplementary lists; proper nouns and transparent compounds, e.g., Doppler, Gaussian, ciphertext, and 7.1% (66 words) were from a specialised engineering word list e.g., actuation, actuator, alloying. The study also identified 856 MWU technical vocabulary items, which can be refined into 543 condensed MWUs e.g., renewable energy, heat transfer, Nusselt number from the EMDC. The distribution of ETV varied across dissertation sections: Results and Discussion sections contained the highest percentage (21.46%), followed by Methodology (20.83%), while the Introduction (18.47%), Literature Review (18.44%), and Conclusion (18.56%) sections showed similar, lower percentages.
The third study investigates learners’ receptive knowledge of the ETV list and lecturers' evaluations of its usefulness. Participants were grouped into three proficiency levels–19 beginners, 33 intermediate, and 26 advanced learners–using the Updated Vocabulary Level Test (Webb, Sasao & Balance, 2017). Yes/No tests were administered to assess learners' receptive knowledge of ETV words selected from the 930 ETV list, while 20 engineering lecturers evaluated the usefulness of the ETV list. The study also analysed correlations between learners’ knowledge and teachers’ perceptions. The findings indicated that learners demonstrated stronger knowledge of high-frequency ETV compared to mid- and low-frequency words. Bootstrapped analysis showed that beginners, intermediate, and advanced learners knew progressively higher percentages of the target words, with advanced learners exhibiting the highest level of comprehension. Lecturers rated high-frequency ETV as the most useful, followed by mid- and low-frequency words. A strong correlation was observed between learners’ knowledge and lecturers’ perceptions, with the alignment improving as learners advanced in proficiency. This suggests that teachers’ perceptions become more accurate as learners develop greater vocabulary knowledge.
This thesis has both methodological and pedagogical implications for research on technical vocabulary in genre-specific written discourse and ESP. The developed wordlists can assist second language engineering students in learning the vocabulary essential for their field, enabling them to meet the language demands of their studies and professional practice. By providing targeted language support, students can enhance their proficiency and perform more effectively in their specialised areas
Isolation, Characterization and Anticancer Evaluation of Alkaloids from Eumachia montana (Rubiaceae)
Get PDFThe dimeric (-)-calycanthine (1), the hexameric (+)-oleoidine (2), the heptameric (+)-caledonine (3), the octameric (+)-eumatanine (4) and a tricyclic pyrroloquinoline alkaloid, eumatricine (5) are alkaloids isolated from the leaves of Eumachia montana; compounds 4 and 5 are previously uncharacterized alkaloids. Preliminary anticancer assays, including MTT, cell count and clonogenic assays, revealed potent inhibition of cell growth and colony formation by compounds 2-4 against seven carcinoma cell lines (including breast, colorectal, lung and glioblastoma multiforme cell lines). The GI50 values of compounds 2-4 ranged from 0.1 to 2.7µM, and potent cytotoxic activity against HCT-116 and MCF-7 was observed (3 > 4 > 2). Cell cycle analysis and apoptosis assays revealed that compound 3 and 4 evokes profound apoptosis without cell cycle phase-specific arrest (under most circumstance except in MCF-7 cells when against 4 at 1 × GI50 for 24h). Additionally, compound 4 also activated caspase, further corroborating the conclusion of apoptosis-induction. Detection of ROS induced by 4 infers a role for oxidative stress in anticancer activity, while γH2AX detection indicates the presence of DNA double strand breaks. Visualization of 4-treated cells by fluorescence microscopy implies multiple cell death pathways are simultaneously triggered (e.g., apoptosis, autophagy, necrosis and paraptosis). Furthermore, metabolomic analysis of 3 and 4 highlights their disruption of membrane integrity through the upregulation of glycerophosphoethanolamine (GPE), glycerophosphocholine (GPC), and acetylcholine (ACh), reinforcing their role in apoptosis induction. These findings provide valuable insights into the mechanism of action of these compounds and their potential as anticancer agents
Analysing intercultural health language: a linguistic (im)politeness study of nursing communication in Saudi hospitals
No full text(Im)politeness remains understudied in Saudi intercultural healthcare settings, where differing norms may influence healthcare practitioners’ perspectives of (im)politeness as well as overall communication outcomes. This study examines how nurses from different cultural backgrounds – Saudi, Filipino and Indian – perceive (im)politeness based on their intra-professional work experience in intercultural medical contexts.
My study adopts a mixed-method design, combining quantitative discourse completion tasks (DCTs) and qualitative semi-structured interviews. The DCT data were collected from nurses’ responses to hypothetical scenarios involving directive speech acts, requests and advice giving, with 50 registered nurses from each group: Saudi, Filipino and Indian. Semi-structured interviews were conducted with 12 registered nurses, four from each group, to gain insights into their perspectives on (im)politeness in the context of their intra-professional communication. The DCT data were analysed using a taxonomy combining two frameworks, Brown and Levinson’s (1987) politeness strategies and Blum-Kulka, House and Kasper’s (1989) Cross-Cultural Speech Act Realisation Project (CCSARP), to identify politeness strategies and markers in nurses’ responses. The interview data were analysed using Brown and Levinson’s (1987) politeness theory and Culpeper’s (2011a) conceptualisation of impoliteness, to understand nurses’ perceptions of (im)politeness in hospital contexts.
The findings revealed that while Saudi, Filipino and Indian nurses reported a primary preference for an indirect communication style, particularly for directive speech acts, the Indian nurses reported significantly greater usage of a direct style compared to Saudi and Filipino nurses. Additionally, there were variations in nurses’ reported use of address terms, with Filipino and Indian nurses using them notably more commonly than Saudi nurses, who rarely reported using them. Such differences in communication styles, along with varying cultural expectations, suggested potential gaps in nurses’ intercultural communicative competence (ICC), which might contribute to communication breakdown.
Building on these findings, my study recommends integrating intercultural training courses for Saudi and non-Saudi nurses prior to clinical work. Such training could address cultural variations in nurses’ communication norms, perceptions of (im)politeness and strategies to reduce miscommunication. Practical components, such as case studies of nursing interactions and role-playing exercises, could enhance nurses’ awareness of cultural differences in language use and foster adaptable communication skills. To maintain long-term improvement, intercultural training should be ongoing rather than one-time, supplemented by mentorship programmes pairing Saudi and non-Saudi nurses. These research-informed recommendations provide nursing policymakers with practical guidance for improving intercultural interaction in Saudi’s multicultural healthcare sector
Understanding Botrytis cinerea infection in strawberries
No full textBotrytis cinerea is a ubiquitous necrotrophic plant pathogen. It has a wide array of virulence mechanisms, enabling it to evade host immune responses, initiate infection and proliferate in the host and neighbouring plants. In strawberries, B. cinerea can infect all the above ground organs and is responsible for both pre- and post-harvest infection. Currently, fungicides are the most effective control method; however, B. cinerea can become recurrently resistant to fungicides and there is growing public concern over fungicide residues on fruit. Therefore, novel control methods need to be investigated to mitigate B. cinerea infection, whilst also appealing to consumers in a sustainable manner. In order to further understand the strawberry-B. cinerea pathosystem, the molecular mechanisms influencing plant pathogen interactions need to be examined.
Pathogenicity assays for strawberry leaves, fruits and flowers were developed to gain a comprehensive overview of how different isolates of B. cinerea infect strawberry plants. Aggressiveness rankings, from high, medium and low, were determined for the isolates, with isolates varying in their ability to infect leaves and flowers, whereas all isolates exhibited high aggressiveness on fruit. Additionally, one isolate with moderate aggressiveness on strawberry exhibited high aggressiveness on Nicotiana benthamiana, indicating isolates can have adaptations for infection on certain hosts.
Resistance to B. cinerea in strawberry is understood to be under polygenic control. To target as many genes as possible, the chemical mutagen ethyl methanesulfonate was utilised to induce random single nucleotide polymorphisms into the genome. The leaf pathogenicity assay was then conducted on the mutant plants, with thirteen exhibiting a change in susceptibility to B. cinerea infection. These more susceptible plants were sequenced and through variant analysis, 774 variants were identified for further investigation. A pipeline consisting of BLASTP searches, determining whether variants were in protein domains, induced amino acid substitutions and were predicted to alter protein structure, along with RNA-seq analysis, was carried out to narrow down which variants could have caused the changes in susceptibility. The candidate resistance genes identified were found to function in established defence pathways, including those involving the plant hormones jasmonic acid, ethylene, salicylic acid and abscisic acid, as well as reactive oxygen species. A list of 26 candidate resistance genes was generated and can now be functionally validated.
Since there was variation in aggressiveness in the B. cinerea isolates, comparative genomics, particularly presence of secreted effectors and phylogenetic analysis, was conducted on 10 B cinerea isolates to deduce if these factors could explain the variation observed. Aggressiveness could not be attributed to the presence of retrotransposons, which contradicts previous evidence in the literature.
Nor was aggressiveness associated with phylogenetic relationships, since the most and least aggressive isolates were grouped in the same clade. Aggressiveness could perhaps be explained, not by predicted secreted effector count, but by the presence of unique secreted effectors, although this requires functional validation. The predicted virulence factors possessed roles regarding competitive fitness between fungi and secretory pathway regulation.
Overall, pathogenicity assays capable of determining quantitative differences in B. cinerea aggressiveness and strawberry resistance were developed. Identifying candidate resistance factors and candidate virulence factors lays the foundation for future work. Should validation confirm that these genes have roles in resistance and virulence, they can inform future breeding strategies by ensuring their presence in new varieties, and aid in the development of targeted, sustainable control methods, ultimately reducing crop losses and improving strawberry production efficiency
The ‘Gated Community’ of North American Women’s Nature Writing: Reclaiming Indigenous Epistemologies and Literary Environmental Activism since the 1970s
No full textThis thesis explores U.S. and Canadian white settler women’s nature writing and Indigenous women’s writing between 1970 and the present. I analyse how the genre of white settler women’s nature fiction is connected to colonial centres of power, and how white settler feminism positions the white settler woman as a colonised subject without fully interrogating how white settler women’s literature has operated in part to maintain and consolidate colonial spatialities and racialised power hierarchies. My analysis brings Indigenous women’s writing and white settler women’s nature writing into dialogue by evidencing how the U.S. and Canadian settler nation-states’ increasing interest in Indigenous ecological epistemologies is reflected by white settler feminism’s romanticisation of indigenisation and appropriation of Indigenous narratives. My thesis is structured into three sections that cover different but interconnected forms of life: Land; Water; and Beyond-Human existence. Each section includes a chapter on Indigenous women’s literary explorations of these elements, followed by a chapter about how white settler women’s nature writing portrays these specific aspects of nature. My readings of Indigenous women’s literature focus on how gynocentric and matrilineal Indigenous knowledges are emphasised as resurgent methods to resist and refute colonial spatialities, temporalities and violence. I examine how Indigenous decolonial feminist portrayals of Indigenous corporeal, land and cultural sovereignty articulate nature through modes of kinship, reciprocity and humility. Written during the Racial Capitalocene, my thesis draws attention to how white settler and Indigenous women continue to use fiction to explore transformational relations with nature that articulate different epistemological and semiotic knowledges, as the man-made impacts of colonialism and capitalism on the environment become increasingly evident
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