VictorJuiz/thesis huggingface dataset:
Environmental drivers of earthen heritage deterioration in dryland regions

Earthen sites form a key part of our heritage: providing us with evidence for past civilisations, acting as a focal point for community identity and forming aesthetically pleasing buildings and structures. These sites are found on every continent but are concentrated in dryland regions, such as across northwest China and central Asia. Due to the low durability of earthen materials, many earthen heritage sites exposed to harsh dryland environments are experiencing extensive deterioration. If we are to pass on these sites to future generations, we need to understand how earthen heritage sites are impacted by environmental drivers of deterioration and how the risk of deterioration could be minimised. To address this challenge, this thesis determines the likely impacts of the main environmental drivers of earthen heritage deterioration under current and future conditions in dryland regions.
The research presented in this thesis examines the impact of wind and rain as drivers of deterioration at Suoyang Ancient City. Suoyang is an archaeological city built out of rammed earth in the Han (206 BC–220 AD) and Tang (618 – 907 AD) dynasties and is located in Gansu Province, northwest China, on the ancient Silk Road. It exhibits a range of deterioration features from the detachment of surface material to wall slumps and collapses. In 2015, an experimental area was established at the site, which includes several test walls.
This thesis uses a combined fieldwork-modelling approach. A controlled field experiment was used to investigate the deteriorative impact of key individual environmental processes on earthen structures. Geomorphological signatures were used to assess the relative importance of wind and rain as drivers of deterioration. These field results were used to develop and parameterise the Vegetation and Sediment TrAnsport model for Heritage Deterioration (ViSTA-HD), a cellular automaton model that spatially resolves the risk of environmental driven deterioration across earthen heritage wall faces. ViSTAHD was used to test the impact of future climatic and conservation scenarios on the risk of earthen heritage deterioration.
Findings showed that even though individual wind events are of low magnitude, their high frequency occurrence results in a significant cumulative impact of wind-driven deterioration under both current and potential future conditions. Increasing natural vegetation cover was found to minimise the risk of deterioration under a range of climatic scenarios.
Given the similarities in material properties, history and location of Suoyang to other earthen heritage sites in Northwest China and central Asia, findings in this thesis can be applied to many other earthen sites in these regions.

Keywords: drylands
cellular automata model
rain
deterioration
wind
earthen heritage
Advisor: Viles, H
Bailey, R
Mayaud, J
Deng Xiaoping and Jimmy Carter: technology transfer and the origin of U.S.-China anti-Soviet cooperation during the Cold War, 1977-1981

This thesis studies how the diverging visions between Jimmy Carter and Deng Xiaoping had shaped the beginning of United States and China’s relationship after the establishment of U.S.-China diplomatic relations. Based on primary sources from the United States, Europe, the Chinese Mainland, Taiwan, and Russia, this study argues that even though both sides were driven together by their shared anti-Soviet views, there were fundamental differences in how the Carter Administration and Deng Xiaoping approached the Cold War: While the Carter administration itself was escalating between the choices of saving détente with the Soviet Union through arms control or using China to pressure the Brezhnev regime, Deng Xiaoping and his Comrades were far more interested in using the escalating tensions between the United States and the Soviet Union to access American and Western military and due-use technologies in order to modernize the Chinese army and to gain a military advantage over Taiwan. This differences not only complicated a series of major cold war issues, from cross-strait relations, nuclear nonproliferation, U.S.-Soviet detente, and China’s role in the European Cold War, but also sow the seeds for future disputes and confrontations between the United States and China.

Keywords: United States
China
U.S.-China relations
technology
diplomatic history
Cold War
nonproliferation
Advisor: Mitter, R
Mechanisms underlying statin-induced modulation of ryanodine receptors 

Statins, a class of HMG-CoA reductase inhibitors, are amongst the most widely prescribed drugs for the treatment of elevated cholesterol. Despite their success, their use is associated with debilitating muscle side effects such a myopathy, myalgia and in the most serious cases, rhabdomyolysis. These effects have limited the ability of many patients to tolerate statin treatment. There is mounting evidence suggesting that statins cause a dysfunction of cellular Ca2+-release in skeletal muscle, which results in muscle damage and myopathy.
In this thesis, I have investigated, using single-channel techniques, how statins interact with the skeletal ryanodine receptor (RyR1), the channel which acts as the pathway for Ca2+-release in skeletal muscle. I have shown that statins as a class, activate RyR1 in a concentration-dependent, reversible manner. These effects were seen at nanomolar levels, which correspond to concentrations found in the skeletal muscle during statin treatment. In contrast, statin effects on the cardiac isoform (RyR2) were more complex, causing inhibition at low concentrations, and activation at higher concentrations, a finding that may be clinically important given the reports that statins reduce instances of arrhythmia.
To investigate if the ability of statins to bind to RyR1 can be reduced without affecting their binding HMG-CoA reductase, the statin minimal pharmacophore was synthesised. It was found not to activate RyR1, indicating that the activation could be separated from the effect on their intended target. Subsequently, single-channel experiments indicated that the RyR1 ATP-site is a plausible location for statin binding, and a molecular modelling study ultilising Autodock software revealed the key structural features required for binding to this site. This facilitated the identification of statin analogues with no effect on RyR1, but potent HMG-CoA reductase inhibition.
In summary, my experiments have revealed that statins can potently alter the activity of cardiac and skeletal RyR channels by distinct gating mechanisms. I suggest that these interactions of statins with RyR channels may contribute to the statin-induced changes in muscle Ca2+-release that are reported in the literature and hence may be the main underlying cause of statin-induced myopathy. In view of this hypothesis, I have screened a number of atorvastatin analogues and identified new statin compounds devoid of the ability to activate RyR1. This work will provide a firm foundation for future work investigating the usefulness of these compounds as lipid lowering agents with reduced side effects.

Keywords: ryanodine receptors
pharmacophore
HMG-CoA reductase
statins
ion channels
Advisor: Sitsapesan, R
Russell, A
Henry James, painters, and painting

In his major essay “The Art of Fiction” (1884) Henry James suggested that the analogy between painting and fiction was, so far as he could see, ‘complete’. Taking him at his word, critics have tended to focus on what the novelist learned from painting, or have fixed on instances in which he ‘chose to elevate the art of the painter,’ as one commentator has recently put it. Contrary to this critical trend, this thesis argues that throughout his corpus James stages a contest between painting and fiction, consistently emphasising the ways in which the latter ought to be considered the superior art. This formed part of a broader programme in which the novelist sought to demonstrate the value and intellectual seriousness of fiction – still in jeopardy in the nineteenth century – by contrasting it with painting. This thesis therefore seeks to revise the ways in which criticism has approached James’s use and appreciation of the painter’s art. It shifts both the terms and the focus of the debate: away from broad correspondences between James’s work and artistic movements such as Impressionism and towards a finer understanding of the novelist’s unique response to painting; away from the supposedly controlling presence of critics such as John Ruskin or Walter Pater and towards the uses to which James put his conception of the painter’s art. In this way, the thesis amends longstanding ideas about the novelist’s response to and communication with painters and painting. At the same time, it reveals through the eyes of a major writer some of the ways in which painting and fiction corresponded in the period. In foregrounding the contexts which animated James’s work – from his negotiation of the transatlantic literary marketplace to his abiding interest in France and the French language, from issues of gender and portraiture to his response to Romantic painting, Pre-Raphaelite art, the Barbizon School, and Impressionism proper – the intention is to elucidate the inner workings of the novelist’s oeuvre. Each chapter is therefore built around a close focus on James’s most consistent passion, his most profound practice: the art of fiction.

Keywords: literary marketplace
nineteenth-century art
literature and art
aestheticism
romantic painting
the novel
portraiture
Henry James
impressionism
Barbizon School
Advisor: Mendelssohn, M
Wright, A
Towards a universally effective HLA-E-targeted HIV vaccine - a structural and biophysical exploration

Through major histocompatibility complex class I leader sequence-derived peptide (VL9) binding and CD94/NKG2 receptor engagement, human leucocyte antigen E (HLA-E) reports cellular health to NK cells. Previous studies demonstrated a strong bias for VL9 binding by HLA-E, a preference subsequently supported by structural analyses. However, Mycobacteria tuberculosis (Mtb) infection and Rhesus cytomegalovirus-vectored SIV vaccination revealed contexts where HLA-E and its rhesus orthologue, Mamu-E, present sequence-diverse pathogen-derived peptides to CD8+ T cells, respectively. In light of unprecedented vaccine-induced Mamu-E-restricted CD8+ T cell-mediated protection against SIV, it is now important to re-explore the peptide binding specificity of the human orthologue, HLA-E, from the view of developing a universal HLA-E-targeted HIV vaccination strategy in humans. Through the development and optimisation of a high throughput in vitro peptide binding assay, we demonstrated an HLA-E binding capacity for a number of pathogen-derived epitopes containing non-canonical anchor residues. As previous crystal structures of HLA-E were exclusively solved in complex with canonical VL9 peptides, we also investigated the structural basis underlying pathogen-derived peptide binding. We obtained a panel of HLA-E crystal structures in complex with a number of Mtb-derived epitopes in addition to the HIV counterpart peptide to the vaccine-identified SIV Gag ‘supertope69’. Strikingly, despite the presence of canonical primary anchor residues, the HIV peptide adopted an alternative conformational motif within the HLA-E peptide binding groove, deviating from that of canonical VL9 and in turn generating a distinct solvent exposure profile, with potential implications for T cell receptor recognition and immunogenicity. Further, combined structural and mutagenesis analyses illustrated a greater tolerance for hydrophobic and polar residues in the primary pockets of the HLA-E binding groove than previously anticipated. Finally, biophysical analyses demonstrated the impact of suboptimal peptide binding on the overall conformational ensemble of HLA-E complexes in solution.

Keywords: HLA-E
HIV
vaccines
T cells
tuberculosis
antigen processing
Advisor: Gillespie, G
McMichael, A
Estimation of fatigue life under multiaxial loading: modelling and experimentation

This doctorate research project investigates the multiaxial deformation and fatigue behaviour of two Nickel-based superalloys used in the discs of aero-engines, named Waspaloy and RR1000, under proportional and non-proportional loading conditions. For that a systematic analysis has been performed to identify and quantify the biaxiality of loading effects on fatigue life, the effects of non-proportional multiaxial loading – including additional cyclic hardening and cross-hardening – on crack initiation and fatigue life, and lastly the role of material micro-structure and crystal orientation on fatigue crack nucleation. An extensive experimental programme with uniaxial and biaxial fatigue tests with Waspaloy and non-proportional tension-torsion tests with RR1000 was carried out. It was experimentally observed that the variation of biaxiality ratio, for the same maximum principal stress, was found to cause a significant change in fatigue life and failure location for Waspaloy. Furthermore, results show that RR1000 presents no load path dependency for stress levels near the yield strength of the material. On the other hand, fatigue lives and cyclic hardening are highly dependent on the degree of non-proportionality. Lives for non-proportional tests were around three times shorter than fatigue lives for proportional tests at comparable stress levels. The experimental programme was used for calibrating and benchmarking a wide range of stress-, strain- and energy-based multiaxial fatigue damage parameters. Most of them could provide a reasonable collapse of both Waspaloy and RR1000 test data. Particularly good fatigue life predictions were obtained with stress-based criteria, especially with Walker stress and Matake’s critical plane approach. Lastly, a GND-coupled crystal plasticity framework and stored energy criterion was implemented for predicting fatigue lives of RR1000. It was concluded that Wan et al.’s stored energy criterion, which combines stress, plastic slip and GNDs density represents an excellent tool for accurately predicting fatigue lives under complex multiaxial loading conditions.

Keywords: multiaxial fatigue
crystal plasticity
non-proportional loading
critical-plane approach
nickel-based superalloys
Advisor: Hills, D
Nowell, D
Thirteen years since the first iPhone: A systematic review on the effectiveness of language learning apps on smart devices

Powered by advanced calculating power and novel technologies like artificial intelligence, smartphone apps offer unprecedent creative solutions in education. They have the potential to change the reality of language teaching and learning. This systematic review critically evaluates the empirical basis for the effectiveness of language learning apps.
A rigorous search on electronic databases and two screenings identified 32 eligible studies, mostly with adults and learners with lower levels of proficiency. The research comprises of two types of comparisons: one compared the effectiveness of different apps or versions of the same app; the other compared language learning apps with other methods of language learning. The research covered a dozen countries, nine languages, nine language skills, 10 commercially available apps and a larger number of researcher-developed ones. 25 of 32 studies found unequivocally positive effects of learning foreign language on apps regardless of functions. Such features as gamification and adaptive learning are conducive to improving language proficiency. Only two studies found participants to score either lower or equally after treatment. A risk of bias assessment reveals that the overall quality of research is low due to inadequate study design and reporting practices.
For language learners, apps can provide affordable and accessible educational resources. However, there is insufficient evidence to show that learners of all ages and proficiency levels benefit equally from apps. Future research needs more robust study designs and should direct attention to study non-adult learners, more advanced learners, and languages other than English.

Keywords: systematic review
language learning apps
m-learning
mobile language learning
e-learning
Advisor: Chalmers, H
Political ideology, racism, and American identity: an examination of white Americans’ support for the police use of excessive force

Under what conditions do white Americans support police violence? And what are the terms by which they do so?
This thesis explores how those who evince the strongest support for police, namely white Americans, “experience” incidents of excessive force, and examines the ideological mechanisms by which they make appraisals about policing. Across two online surveys of white American adults, varying the racial identity (white/black) of a police officer and suspect in a fictional scenario of violence showed no effect on respondents’ assessments of the encounter. Instead, ideological commitments to individualism, as measured in in just-world (Lerner 1980) and libertarian-authoritarian (Heath et al. 1994) attitudes, were associated with strikingly high levels of support for excessive force.
I situate these empirical findings within a broader theoretical argument about white American identity, and the ideologies, mythologies, and pathologies that sustain it, namely the American Dream emphasis on desert, merit, and self-enterprise. I argue that excessive force is made legible through a frame of personal responsibility, with national and political identities influencing how white Americans, specifically, perceive and reconcile inequality. I suggest this way of “seeing” may explain why so many white Americans, in particular, continue to support the police.
This research moves beyond identifying socio-demographic correlates for the approval of police violence, and uses rich theoretical examination and original survey data to investigate the role that racism and political ideology play in explaining white Americans’ beliefs about the appropriateness of excessive force.

Keywords: social psychology
racism
political ideology
police violence
American politics
Advisor: Bradford, B
Loader, I
Effect of photoacclimation on bio-optical properties of marine phytoplankton

Photoacclimation in marine phytoplankton is manifested through changes in pigment composition and has a significant impact on in vivo light absorption. Results obtained from this thesis work clearly show that the variability in the chlorophyll a (Chl-a)-specific absorption coefficient of phytoplankton at 440 nm (a*ph (440)) observed over a broad latitudinal gradient of the Atlantic Basin was influenced significantly by changes in the concentration of non-photosynthetic pigments (NPPs) relative to total pigments (the NPP index), whereas pigment indices of cell size showed a weaker correlation with a*ph (440). Spatial and seasonal changes in the NPP index were the combined result of photoacclimation and the photoadaptive variation in pigment composition of dominant prokaryotic and eukaryotic groups. Variability in the spectral shape (indexed by the spectral slope) of phytoplankton absorption could be largely explained by NPPs, particularly zeaxanthin (a marker for marine picocyanobacteria) which was highly abundant in the (sub)tropical oligotrophic gyres due to the predominance of the marine picocyanobacterium Prochlorococcus. In Prochlorococcus-dominated waters, depth-dependent variation in the NPP index was driven primarily by variation in the intracellular concentration of photosynthetic pigments (PSPs), rather than NPPs, which was the result of both photoacclimation and a shift in dominant ecotypes. Photoacclimation of this globally-significant genus was also clearly reflected in the strong vertical change in the intracellular concentration of the dominant light harvesting pigment, divinyl Chl-a (DVChl-a). The flexibility in the DVChl-a cell−1 in Prochlorococcus leads to a more highly variable carbon-to-DVChl-a ratio (θPro) observed in this genus than in other phytoplankton groups. θPro was shown to be highly correlated with both the NPP index and the spectral slope between 443 and 550 nm, which suggests that both of these indices may serve as useful predictors of θPro. In strongly-stratified, oligotrophic waters where the NPP index may be considered a proxy of ambient light levels, the NPP index could account for a significant fraction of the variability in the parameters describing the photosynthesis-irradiance (PE) response curve. Using estimates of θPro derived from its relationship with the NPP index, the maximum growth rates for surface Prochlorococcus populations (μm, Pro) were calculated from maximum Chl-a-specific photosynthetic rates measured at the Prochlorococcus-dominated stations, yielding an average μm, Pro value of 0.22 d−1 , which is consistent with field and culture studies. Thus, the NPP index can be considered a useful proxy of both the photoacclimatory status and photophysiological characteristics of phytoplankton in subtropical marine ecosystems.

Keywords: phytoplankton
bio-optical properties
photosynthetic parameters
photoacclimation
Advisor: Bouman, H
Zhang, Q
Devising new biomedical imaging applications for metallodrugs based on an improved understanding of their electronic and magnetic properties

Ligand field anisotropy plays a key role in defining the spectroscopic properties of lanthanide complexes. Changes to the local ligand field can have profound consequences for the NMR, luminescence and EPR properties of lanthanide ions with inherent anisotropy. In this project ligand field effects are shown to be significant for even Gd(III) complexes, where the ground state of the free ion has an isotropic electron distribution. In these systems, changes to the ligand field and the axial donor are shown to have dramatic effects on the form of the EPR spectrum. These can be rationalized through considering the donor set. A number of EPR techniques were used to characterize the systems: CW EPR and pulsed PEANUT measurements can be correlated with the splitting of the Ms states within the 8S ground state of Gd(III).
These effects can also be seen for systems with broken symmetry and these variations, with relatively small changes to the local field, can provide useful information and aid in the development of new contrast media. There are also potential further applications for electron polarization agents for DNP MRI. This potential was explored using CW EPR of polymetallic lanthanide complexes and subsequent DNP NMR experiments. Whilst build-up of hyperpolarization could be observed, further development of these complexes is needed in order to surpass the current “gold-standard” and be translated for clinical practice.

Keywords: EPR
Gd(III) Complexes
Lanthanide Chemistry
DNP MRI
Ligand field anistropy
Advisor: Faulkner, S