VictorJuiz/thesis huggingface dataset:
Polymerisation catalysts enabling carbon dioxide utilization
Keywords: polymerisation
carbon dioxide
ring-opening copolymerisation
homogeneous catalysis
carbon dioxide utilisation
catalysis

This thesis describes the development of homogeneous catalysts for epoxide/carbon dioxide (CO2) ring-opening copolymerisation (ROCOP). The objective is to increase understanding of the polymerisation mechanism and factors controlling catalyst performance. It ends with an application of the best catalyst to polymerisation of epoxide, carbon dioxide and lactide using ‘switch’ catalysis.
Chapter 1 provides an introduction to the ROCOP of epoxides and CO2, with a particular focus on catalyst development and mechanism. It also introduces the concept of ‘switchable’ catalysis.
Chapter 2 details the mechanistic exploration of a high performance heterodinuclear Co(III)K(I) catalyst for propylene oxide/carbon dioxide (CO2) ring-opening copolymerisation (ROCOP). A detailed computational investigation of the full catalytic cycle is performed and barriers match with experimental ones. The proposed mechanism occurs with a rate determining step involving epoxide activation at Co(III) and nucleophilic attack by a carbonate bound to the K(I). Further examination, both experimentally and computationally, of the cyclic carbonate formation is undertaken and showed that it occurs via both a random chain scission and chain ‘unzipping’ mechanism.
Chapter 3 details a structure-activity study of the Co(III)K(I) catalyst system underpinned by the findings in Chapter 2. The investigation explores the effect of ligand structure on the Co(III/II) redox potential, activity and selectivity in propene oxide (PO)/carbon dioxide (CO2) ring-opening copolymerisation (ROCOP). It rationalises the effects of these changes using the polymerisation mechanism. The key finding is that a lower redox potential, corresponding to higher electron density at Co(III), leads to higher activity and selectivity in propylene oxide (PO)/carbon dioxide (CO2) ringopening copolymerisation (ROCOP).
Chapter 4 details the application of a high activity and selectivity Co(III)K(I) catalyst to the ‘switchable’ catalysis of ally glycidyl ether (AGE)/CO2 and L-lactide (L-LA), producing a block polymer (PLLA-b-PAGEC-b-PLLA). The experimental method, involving a new gas line, is developed and the characterisation proofs of ‘switch’ are presented.
Chapter 5 outlines the key developments of this thesis and suggests potential future directions for the research.
Chapter 6 provides experimental details for Chapter 2-4.
Chapter 7 is an appendix that provides supplementary information, figures and data that support the work and discussion through Chapter 2-4.
Acoustic cue-weighting in L1 and L2 English vowel perception
Keywords: L2 phonology acquisition
English /i:/-/ɪ/
acoustic cue weighting
ALSLA2023

Listeners identify phonemes of a language via acoustic cues. For instance, the English /i:/-/ɪ/ vowels are distinguished by the vowel length and spectral range between the first (F1) and second (F2) formant frequency of the vowels. The research in this dissertation examined perceptual weighting of two acoustic cues, namely vowel duration and spectra, in the perception of English /i:/-/ɪ/ vowel contrasts by native speakers of British English and Chinese L2 learners of English. First, it asked how native speakers and L2 English learners weighted the cues at the group level. Second, it investigates the individual differences for the native and L2 group and what had caused such variability in the L2 speakers. Third, this research examined instruction’s role on cue weighting of English /i:/-/ɪ/. In Experiment 1, a total of 29 native speakers of British English and 29 Chinese L2 learners of English identified the vowels in synthesized ‘bead-bid’ and ‘steet-stit’ continua which differed in 7 spectral and temporal steps. After the forced-choice task, each participants completed a background questionnaire. Experiment 2 adopted a pre- and post-test design, where a total of 48 L1- Mandarin L2 English learners (23 participants in the control group and 25 in the experimental group) completed similar word identification task as in Experiment 1. The experimental group completed a treatment session where they were explicitly instructed in the differences between English /i:/-/ɪ/, while the control group heard the same minimal pairs of the contrast without the instruction. Participants in Experiment 2 also completed the background questionnaire. The results showed that, at the group level, both the native speakers and L2 learns relied predominantly on vowel duration. Substantial variability of cue weighting behaviors was found at the individual level for both L1 and L2 English speakers, but neither self-perceived English proficiency nor experience of living in English-speaking countries were found to have significant influence on cue weighting at the group level. Regarding the role of instruction, Experiment 1 found previous instruction as a significant predictor of the L2 cue weighting pattern. Experiment 2 found no evidence of such influence of instruction from the correlational perspective, but it did find that, from the causal perspective, intervention of explicitly instructing the participants about the differences between English /i:/-/ɪ/ had led the experimental group to down-weigh the vowel duration.
Iran’s turn to the east? The role of ideology in the Islamic Republic’s foreign policy in Central Asia (1990-2001)
Keywords: Four Pillar model of ideology
Foreign Policy
Structuration theory
Islamic Movement of Uzbekistan
Post-soviet politcs
Central Asia regional politics
Transnational terrorism
Ideology in foreign policy
Tajik Civil War
Islamic Republic of Iran

This thesis investigates the ways in which Iran’s post-revolutionary ideology has contributed to shaping the foreign policy of the Islamic Republic towards Central Asia after the fall of the USSR (1990-2001). It asks to what extent ideology played a prominent role in shaping Iran’s initial foreign policy strategy towards the newly independent Central Asian republics, and to what extent it remained a relevant factor in Tehran’s policy shifts through the 1990s. This topic has been chosen with the aim of synthesising two unconnected schools of thought in the literature on Iranian foreign policy, where there has been a tendency to centre the study of Iran-Western relationship around ideology, while Iran-East relations are often seen through a political economy lens. This thesis advances a new theoretical model to study the interaction between Iran’s post-revolutionary ideology and its foreign policy, the Four Pillar Model. This is a morphological model inspired by Gidden’s structuration theory, which proposes Pan-Islamism, Pan-Iranism, Anti-Imperialism, and National Sovereignty as the four core elements of Iran’s ideology. The model is tested against three case studies: the dissolution of the USSR (1990-1992), the Tajik Civil War (1992-1997), and the insurgency of the Islamic Movement of Uzbekistan (1999-2001). This thesis claims that the internal contradictions in Iran’s ideology determined the emergence of a ‘dual-track policy’ in Central Asia in the 1990s. Though Iran’s foreign policy oscillated from Pan-Islamism to Pan-Iranism and back, both foreign policy approaches continued to co-exist, striving for primacy. This strife reflected the struggle between different interpretations of the identity of the Iranian regime, but it was also strongly influenced by geopolitical changes in the region. The increase in American involvement in Central Asia after 1995 and its effect on regional power alignments and energy markets were paramount in tilting the scales back in favour of Pan-Islamism.
Fragments of mind: a thesis on the subject of experience, the structure of consciousness, and split-brain patients
Keywords: split-brain experiments
phenomenal consciousness
access consciousness
the unity of consciousness
split-brain patients
spatiotemporal experience
transitivity of co-consciousness
streams of consciousness

Neuropsychological research on so-called split-brain patients—individuals whose corpus callosum has been severed as a treatment for severe epilepsy—has revealed the possibility of startling breakdowns in the transmission of sensory information between the cerebral hemispheres. These experimental results have often been interpreted as demonstrating that split-brain patients have two streams of consciousness. In opposition to such views, this thesis argues for a conception of split-brain patients as having a single stream of consciousness that’s disunified in highly specific experimental settings but unified outside of those settings. It is also argued that conceptions of split-brain patients as having two unified streams of consciousness and conceptions according to which they have one consistently unified stream of consciousness rely on a mistaken assumption: That a set of experiences belong to a stream of consciousness if and only if all the contemporaneous experiences in the stream are unified with each other.
The early cellular events that control mechano-inflammatory signalling after cartilage injury
Keywords: cartilage
mechanical injury
ASK1
chondrocytes
mechanoflammation
IL1
osteoarthritis
reactive oxygen species

Osteoarthritis (OA) is a degenerative joint disease that has no disease- modifying drug licenced for its treatment. Mechanical injury of cartilage is a principal risk factor in osteoarthritis (OA). Recent insights arising from our group demonstrate that mechano-sensitive intracellular signalling drives disease pathways. Cartilage injury is known to activate inflammatory signalling that leads to production of matrix-degrading proteases and consequent cartilage breakdown – a process our group has called mechanoflammation. Cartilage injury induces activation of transforming growth factor-β activated kinase 1 (TAK1), that further activates downstream extracellular signal regulated kinase (ERK), p38 and Jun N terminal kinase (JNK) mitogen-activated protein kinases (MAPKs). Our group has previously identified the role of apoptosis signal regulating kinase 1 (ASK1) and reactive oxygen species as key drivers of MAPKs on cartilage injury and downstream inflammatory gene regulation. My project sought to identify the role of ASK1 in the cartilage injury response. ASK1 was phosphorylated rapidly after cartilage injury, leading to the accumulation of ASK1 protein in the cell. Inhibition of ASK1 phosphorylation suppressed ASK1 accumulation, suggesting that phosphorylation was responsible for stabilising ASK1, most likely, by preventing its degradation. Degradation was through a proteosome- dependent mechanism as stabilisation of non-phosphorylated protein could be induced by pre-incubation with a proteosome inhibitor. IL1 and H2O2 stimulation of isolated primary chondrocytes activated MAPKs and NF-κB but did not appear to involve ASK1, although this needs repeating. Attempting to inhibit ASK1 in murine OA did not suppress cartilage degradation nor osteophyte formation. Giving mice a modified diet of oxidation-resistant compounds appeared to reduce injury-induced inflammatory gene regulation in vitro but increased cartilage damage in murine OA. My findings provide further insight into the role of ASK1 and other mechano-inflammatory pathways in articular cartilage and highlight the challenges of inhibiting them in vivo.
Invisible barriers for the Gulf market integration in light of the political economy of the region
Keywords: Indian Ocean
Regional Integration
Gulf Cooperation Council

This dissertation presents an economic history of Gulf regionalism, drawing on qualitative written materials from Kuwait, Qatar, Saudi Arabia, and London to illuminate historical patterns of market integration in the region and shed light on the historical transformations of the Gulf’s regionalism process. It also explores how Gulf regionalism was shaped during the late nineteenth and twentieth centuries, as well as the underlying events and circumstances and the nature of Gulf regionalism.
Here, the Gulf’s regional history is approached through the concept of regional space, which emphasises human dimensions and mechanisms in the analysis of regional connectivity, in addition to geographical dimensions. Using the concept of regional space, this dissertation deeply examines how members of the Gulf mercantile community actively shaped the contours of the commercial space that they occupied.
The findings of this study suggest a strong link between the tendencies to regional integration in the Gulf and the nature of the dominant mercantile activities in the region and the attendant means of wealth accumulation. These findings suggest that the emergence of a more centrist concept of economic activity during the late nineteenth and twentieth centuries influenced integration tendencies in the region promoting a weak regional order. In this transformation, Gulf regionalism process moved from being a window for local markets to Indian Ocean networks, to being an inter-governmental institution promoting visions of economic development in regimes.
In tracing the transformation of Gulf regionalism, four turning points have been identified that largely define the Gulf’s regionalism process: 1) World War I and the subsequent creation of borders in the interwar years; 2) the decline of the pearl economy during World War II and the divergence of Gulf port towns; 3) the first oil boom in the 1950s and the change in patterns wealth accumulation; and 4) the British withdrawal from the region in the 1970s and the formation of the Gulf Cooperation Council.
At the same time, this study also considers the global dimensions of the four turning points as manifested in the historical shifts in the British presence in the region. From the early protectorate agreements to the establishment of the first desert post and the birth of the nation-states, British officials also played a significant role in shaping the contours of the Gulf’s regional space. This study finds that British officials significantly reorganised economic life in the region as they sought to serve Britain’s prestige and commercial interests.
Communities of practice theory in Egyptian archaeology: a case study for its application with Old Kingdom sealings and seal impressions from Giza
Keywords: archaeology
administration
archaeological theory
communities of practice
ancient Egypt
seal impressions
sealings
Old Kingdom

Theoretical approaches for reconstructing social dynamics in ancient Egypt are increasingly being employed by Egyptologists. The motives behind this development are the enlightenment of certain issues that traditional archaeological methods and methodologies cannot provide. One such theory that has not been tested in this context, but has great potential, is communities of practice. The communities of practice methodology includes concepts that can examine how individuals interact with other people, their objects and their environment to learn and produce a practice (as understood by Bourdieu and Giddens). It has considerable potential for illuminating the world of ancient Egypt (as well as other ancient civilizations).
Drawing on two case studies from the Old Kingdom (ca. 2613-2181 bce), this thesis tests a hypothesis that communities of practice theory can be effectively used to illuminate processes of learning, practice, relationship-building and continuity as they relate to administrative sealing. The data for my first case study derives from seal impressions and sealings excavated at Pottery Mound in Heit el-Ghurob, Giza as a means to question whether communities of practice offers ways for understanding small scale sealing practice and daily interactions. The data for my second case study originates from seal impressions and sealings excavated at other sites in Heit el-Ghurob, Gebel el-Quibli, Khentkawes Town and Silo Building Complex on the Giza Plateau. This case study explores how knowledge networks and shared sealing practice work at larger scales. These datasets are analyzed with the communities of practice methodology, as a means to gain new insights into ancient sealing practice and administration.
‘In-person and online’: Experiences of in-person instruction for UK secondary students during the 2020 pandemic
Keywords: education
EdTech
qualitative interviewing
inequality
lockdown
UK
online learning

During the COVID-19 pandemic, the UK was one of the many countries around the world who kept schools open to provide in-person instruction for vulnerable pupils and the children of essential workers. Attendance of in-person instruction in the UK peaked at 17.5% in July of 2020 and most school leaders indicated that there were between 10 and 29 pupils attending in-person instruction. Yet, the experiences of students who attended school in-person have had comparatively little study and it has been assumed that their experiences were approximately similar to students attending online instruction from home. The aim of this research is to investigate the unique experiences of UK secondary students who attended school in-person during the COVID-19 pandemic. In particular, this study evaluates how the complex relationship between digital technology and the socio-spatial context of schools mediated students’ experiences of in-person instruction. Semi-structured interviews were conducted with twelve students in UK secondary schools. These interviews were then transcribed and coded for key themes. Overall, the students felt that being in-person provided them with more opportunities to socialize, form close relationships with friends and teachers, and access academic and socio-emotional support. However, some also struggled to gain a sense of normality at school due to the heightened regulatory environment, anxiety about coronavirus, and greater loss of autonomy over their own lives. In contrast to narratives of the ‘disruptive’ effect of education technology, students demonstrated a high level of agency over their use of digital technology and felt that they were able to quickly adapt to online remote instruction.
Non-contact monitoring of skin perfusion as a proxy for haemodynamic status
Keywords: haemodynamic
skin perfusion
camera

The examination of skin perfusion is a key component of haemodynamic assessment. The body is quick to redirect blood flow away from the skin during periods of haemodynamic instability, making it a sensitive site for an early detection of cardiovascular compromise. The clinical assessment of skin perfusion is mostly subjective. As an external organ, however, it is possible to objectively assess skin perfusion using video cameras operating both within and outside the visible light spectrum.

The use of video cameras in clinical monitoring has been explored in vital-sign estimation, and may offer both objectivity and higher sensitivity compared to the current subjective assessment of skin perfusion. However, its evolution as a monitor has been held back by practical challenges such as vulnerability to signal noise from movement and lighting changes. This thesis describes the Mapping Of Lower Limb skIn pErfusion (MOLLIE) study, in which phenylephrine and glyceryl trinitrate (GTN) were used to pharmacologically induce skin perfusion changes in healthy volunteers under controlled environmental conditions. The participants were monitored using a variety of video cameras.

Using this dataset, several streams of analyses are presented. First, image processing techniques are used to quantify clinically visible skin mottling. Following the measurement of these direct correlates of visually detected clinical findings, the remainder of the thesis demonstrates the detection of induced skin vasoconstriction and vasodilation which is not readily visible to the naked eye. A differential response to perfusion changes in different regions of skin is described, related to the underlying vascular anatomy of the skin.

This thesis argues that video cameras can provide additional insight into the haemodynamic status. It is only by combining the knowledge of skin as an organ and its blood supply with the available image processing techniques that we can fully understand the information present in the measured parameters at the skin surface and improvements can be made in skin perfusion monitoring.
Spatiotemporal brain dynamics induced by propofol and ketamine in humans
Keywords: propofol
EEG
ketamine
anaesthesia

Human brain dynamics are radically altered under the influence of anaesthetics. However, despite their widespread clinical use, the whole-brain mechanisms by which anaesthetics alter consciousness are still not fully understood and clinical translation of existing insights is limited. This thesis presents several lines of investigation aimed to improve our understanding of spatiotemporal brain states under the anaesthetics propofol and ketamine.
First, slow-wave activity saturation (SWAS) was studied across the brain and in relation to existing depth of anaesthesia markers. Local propofol concentration needed to achieve SWAS in healthy volunteers correlated with GABA-A receptor density (Spearman ρ=-0.69, P=0.0018), providing more evidence for the importance of the neurophysiological state of SWAS. The average Bispectral Index at SWAS across volunteers was 49±4, but its value varied significantly over time.
Second, relevant cortico-cardiac interactions were studied. A slow propofol infusion increased heart rate in a dose-dependent manner (increase of +4.2±1.5 bpm / (μg ml-1), P<0.001). Individual cortical slow waves were coupled to the heartbeat (P<0.001), with heartbeat incidence peaking about 450ms before slow-wave onset. A ketamine case study showed decreased amplitude of heartbeat-evoked potentials, suggesting impaired interoceptive signalling may have a part in dissociative phenomenology.
Third, novel methodology was developed, validated, and applied throughout the thesis. Iterated Masking Empirical Mode Decomposition was used to identify three types of low-frequency propofol waves with different spatiotemporal maps and dose-responses. Hidden Markov Modelling of propofol showed a shift to anterior alpha states and a reduced switching rate (P<0.01); with ketamine states exhibiting low alpha power and decreased connectivity became more prominent (P<0.001).
Fourth, the potential of translating electroencephalographic markers from high- to low- density montages was studied. Posterior montages were best at capturing the reduced state switching under propofol. A patient study of antidepressant ketamine treatment demonstrated reduced temporal lobe alpha and theta power were associated with dissociation (P=0.0109).