VictorJuiz/thesis huggingface dataset:
The photophysics of metal halide perovskites for next-generation solar cells

Metal halide perovskites have emerged as a promising absorber material for efficient third generation solar cells. In this thesis, the photophysics of these materials are investigated by photoluminescence and optical absorption spectroscopy, focussing on the charge-carrier recombination dynamics and the band gap. The work primarily discusses tin-based perovskite materials, which allow the band gap to be tuned to lower values but currently display poor power conversion efficiencies due to rapid charge-carrier recombination. In addition, the effect of thickness on lead-based perovskites is investigated, allowing the band gap to reach higher values by quantum confinement.
First, the temperature dependent photoluminescence of MASnI3 is examined. A dramatic reduction in PL spectral linewidth with a concomitant increase in PL lifetime is seen at the low temperature structural phase transition. This points to the deactivation of defects, thus reducing scattering and recombination. Defect tolerance may therefore be related to the structure of the perovskite and could be enhanced by a targeted structural change to increase the charge-carrier lifetime and improve solar cell efficiency.
Further to this, the PL lifetime and relative radiative efficiency of FASnxPb1-xI3 are investigated to uncover how metal composition influences charge-carrier recombination mechanisms. The PL dynamics fall into two regimes, with the tin-rich samples displaying fast mono-exponential decay that is largely temperature-independent, and lead-rich samples having longer, more stretched decays dominated by multi-phonon recombination. Band gap bowing of the mixed metal FASnxPb1-xI3 perovskites is found to be parabolic at all temperatures, and is most likely due to local deformations in the lattice to accommodate the random placement of lead and tin ions. The benefits of a lower band gap may therefore be achieved whilst keeping the slower charge-carrier recombination of lead perovskites, thus enabling high efficiency bottom cells for all perovskite tandem solar cells.
Finally, the prospect of band gap tuning is investigated from a different angle, by growing very thin films of MAPbI3 by vapour deposition which display quantum confinement. Films initially grow as islands, with blue-shifted photoluminescence, before forming uniform films still thin enough to exhibit quantum confinement. These films could be used to develop efficient LEDs, and the exposition of the growth mode could also lead the way to producing large-area vapour deposited solar cells with larger grain size which improves both efficiency and stability.
Together, the results show that the metal composition, the structural phase (which can be adjusted by changing the organic and halide ions) and the dimensions of the material, can all impact the optoelectronic properties, allowing great scope for tuning the properties of these materials to optimize their photovoltaic performance.

Advisor: Herz, L
Snaith, H
Actor-network theory and the action of biblical texts

This thesis is an investigation of the mechanisms of textual performativity: how do biblical texts bring about change, such that they can be thought of as enacting and configuring social reality? This methodology begins with Bruno Latour’s work on actor-network theory, and proposed here is a model for the performativity of texts as nonhuman actors embedded within actor-networks.
Three theoretical components form the basis to the argument: 1) Texts are nonhuman actors that have agency and act within actor-networks. Within these actor-networks, the text mediates the agency and action of other actors, shifting, transforming, and betraying the meaning and action it carries from the writing event to the reading event. 2) A text functions both as an artifact and a being of fiction, with action that emerges in the relationship between text and other objects to which it is attached, such that notions about the text are assembled together with the text and other actors, together configuring its action. 3) The text’s action as a Latourian mediator provides the text with autonomy, and it is, thus, the reader’s notion of meaning, not the author’s intent, that is performative in the reading event. Any notion, however, of the creative event held by the reader shapes this emergent meaning. Finally, because texts are performative, notions of what an author meant, of a text’s production, and of how to read are caught up in politics. In this analysis priority is given to what is rather than what ought to be, in what is referred to as a Realhermeneutik approach.
In order to develop this theoretical framework with practical analysis, throughout this thesis, examples are drawn from the action of the Bible within American evangelicalism, concluding with a chapter that demonstrates this methodological approach by tracing the participation of the Bible in climate change.

Keywords: textual performativity
reader response theory
evangelicalism
American evangelicalism
Bruno Latour
textual agency
nonhuman agency
climate change
biblical performativity
reception criticism
beings of fiction
actor-network theory
actants
Advisor: Barton, J
Ward, G
Intergration of microtubule-kinetochore attachment formation and spindle assembly checkpoint signalling

This study focuses on mitosis and the regulation of microtubule-kinetochore attachment formation by phosphorylation. Kinetochores act as platforms for both the attachment of bi-polar spindle microtubules to chromosomes and the generation of the surveillance systems which regulate this process. Both the error-correction pathway and the spindle assembly checkpoint are activated in the presence of non-attached or non-tension bearing kinetochores. These mechanisms rely on dynamic phosphorylation and dephosphorylation for the transduction of signals allowing the regulation of protein:protein interactions.
Many kinetochore proteins have been found to be highly phosphorylated in mitosis, but less is known about the temporal regulation of these phospho-sites. In addition, only a small proportion of sites and their biological function have been investigated in detail.
Here, I have developed a mass spectrometry protocol combined with a synchronisation step to isolate the outer kinetochore and compare the phosphorylation state at unattached and attached kinetochore states. Our analysis showed that multiple phosphorylation sites on the outer kinetochore are dephosphorylated upon attachment. As key examples we identified the six active MELT motifs on Knl1, which regulate the recruitment of SAC proteins. Intriguingly, we also identified two Ndc80 phosphorylation sites, pThr61/Ser62 and pSer69, which are up-regulated upon kinetochore-microtubule attachment. This suggests that the regulation of microtubule attachment to the outer kinetochore by different kinases may be more complex than hitherto thought, as up-regulation upon attachment has so far not been reported.
As an example of a specific kinase-regulated protein complex involved in the generation of microtubule-kinetochore attachment formation we investigated the role of Plk1 associating with the Astrin-Kinastrin complex. Previous results in our lab showed depletion of Astrin or Kinastrin +results in delayed chromosome alignment and loss of spindle bipolarity. In this study we demonstrate that Plk1 binds directly to Astrin via a Cdk1-phosphorylated sequence in the N-terminus of Astrin. Using mass spectrometry we identify four Plk1-dependent phosphorylation sites on Astrin at residues, pSer157, pSer159, pSer353 and pSer411 and demonstrate that phosphorylation of these sites is dependent on Plk1 activity in vivo. Interestingly, we can demonstrate that the interaction of the Astrin-Kinastrin complex with Plk1 is dispensable for bipolar spindle formation but does play a role in timely chromosome congression and anaphase onset, thus separating the different aspect of the Astrin/Kinastrin depletion phenotype.
Retroactive recharacterisation of crimes: the principles of legality and fair labelling in international criminal law

The principle of legality is one of the most fundamental principles of criminal law. It requires crimes and penalties to be established by law at the time of the conduct. In international criminal law, it applies as a rule of custom, treaty and a general principle of law. Nonetheless, the principle sits uneasily with some unique features of the international legal order, particularly its multiple adjudicative and prescriptive authorities. This has led to a frequent but overlooked practice known as ‘retroactive recharacterisation of crimes’. This occurs when, upon charging, convicting or sentencing the accused, an international or domestic tribunal substitutes new rules of criminal law for those applying at the time of the conduct. Retroactive recharacterisation of crimes has been justified on the basis of a cursory reading of the principle of legality in general international law, which, on closer look, does not seem to accommodate some of its problematic outcomes. It is also unclear whether this phenomenon is consistent with the principle of fair labelling, which necessitates criminal labels to be representative of the accused’s blameworthiness. This thesis seeks to answer two principal research questions. First, how are the principles of legality and fair labelling to be applied in international criminal law generally and in the specific context of the International Criminal Court? Second, to what extent is the phenomenon of retroactive recharacterisation of crimes consistent with them, bearing in mind their elements, scope and rationales? Its central claim is that, although not per se contrary to both principles, changes in the applicable criminal law which substantively affect the fundamental rights of the accused, including the imposition of more stigmatising labels, may be unlawful. To address this, the substantive criminal law binding on the accused at the crime of the conduct ought to be applied as such.

Keywords: Non-retroactivity
International Criminal Law
International Criminal Court
Legality
Fair Labelling
Advisor: Akande, D
Becoming families: a study of same-sex couples' rights in the Anglo-Saxon countries

The politics surrounding the recognition of same-sex couples has found uneven analysis in the extant literature. While the dynamics in the United States and Western Europe are well-documented, the processes in the Anglo-Saxon countries is less advanced. This oversight is two-fold. First, the empirical record regarding the historical evolution of same-sex couples’ rights is wanting. Second, the theoretical framework of morality policymaking is unevenly theorised and therefore ill-equipped in dealing with this set of countries. This set of countries, therefore, is chosen to advance the extant theories regarding the politics of same-sex couples’ rights. In short, this thesis aims to add to the empirical evidence and advance the theorisation of morality policy in ‘secular’ countries; that is countries which do not feature a politically relevant state-church conflict.
The thesis pursues this goal through four cases studies that each rely on qualitative research methods. First, it develops a theoretical framework to show the secularisation and contractualisation of opposite-sex marriage and outlines these processes’ importance for same-sex marriage advocacy. Second, it uses the experience of the Anglo-Saxon countries to develop a new judiciary-based mode of international policy transfer. Third, it uses the case of same-sex union recognition in Australia to develop the morality policy framework in regard to secular countries. This analysis expands to the extant understanding of morality policymaking in particular regarding parliamentary democracies of the Westminster type. Fourth, the thesis analyses the Adoption and Children Act 2002 in England and Wales to understand why same-sex couples were granted joint adoption rights before any form of formal union recognition.
The results of these case studies indicate that the morality policy framework is only partially useful for explaining the politics in Anglo-Saxon countries. In setting the parliamentary agenda, the executive has very strong albeit not absolute control. In the legitimation of policy, the competition between ‘progressive’ and ‘traditionalist’ frames is confirmed, as is the ability of the executive to reinforce its preferred policy definition in the case of latent morality policies. However, the treatment of manifest morality policy requires the careful analysis of intra-party fractions and vested interests. Further research is required to test the theoretical frameworks built in this thesis and in particular the applicability of the morality policy framework in similar countries.

Keywords: Ireland
Australia
same-sex marriage
Anglo-Saxon Countries
social policy
marriage policy
United Kingdom
LGBT
New Zealand
politics
Canada
Advisor: Daly, M
Evaluating effects of antibiotic treatment on resistance and patient outcomes using linked microbiology and patient electronic health record data

There is substantial pressure on medical services to reduce antibiotic prescribing, aimed at reducing the spread of antimicrobial resistance. Reducing prescribing in the acute hospital setting provides unique challenges, with antibiotic decisions made in the first few hours of admission with uncertainty over both diagnosis and severity of illness. The potential benefit to the patient must be balanced with the risks of side-effects and of future resistant infections to both the patient and the population as a whole.
I first review the evidence currently available to the acute clinician to assist in this decision. I then conduct a small study of antibiotic use in the acute medical setting, demonstrating that whilst substantially reducing antibiotic initiation and prescribing is possible, this is at the cost of more admissions and longer length-of-stay. I highlight the need for larger studies to meaningfully assess clinical outcomes, including resistant infections.
I then perform two studies investigating the accuracy of electronic health record data. The first assesses to what degree diagnostic codes can be used to estimate Charlson comorbidities to enable risk-adjusted studies of clinical outcome, concluding that diagnostic coding is relatively robust. The second assesses the degree to which diagnostic codes can be used to identify infections and their bacterial cause, finding that careful data curation is required, and significant limitations exist in using coded data to study causative organisms.
I use results from these studies to inform the subsequent design of a study of patients with Escherichia coli and Klebsiella pneumoniae bloodstream infections using linked electronic health record data and laboratory microbiology results. I find that previous broad-spectrum beta-lactams and trimethoprim exposure are associated with beta-lactam resistance in these infections at the level of an individual patient, but no evidence of association between duration of antibiotic exposure and development of resistance.
This work supports current efforts to limit use of broad-spectrum antibiotics, particularly beta-lactams, and to encourage the clinician, if an antibiotic is required, to try and use narrow spectrum antibiotics. It also showcases the power of electronic health record data, if used carefully, to progress the current knowledge in identifying rational prescribing strategies to reduce development of antimicrobial resistance.

Advisor: Peto, T
Crook, D
Walker, S
Epidemiology of environmental enteric dysfunction, malnutrition and intestinal microbiota amongst children in Kilifi, Kenya

Environmental Enteric Dysfunction (EED) is a chronic intestinal inflammatory disorder that is highly prevalent amongst children in tropical low-income settings and associated with stunting (low height-for-age). I undertook two studies in coastal Kenya that aimed to explore the aetiology of EED. Firstly, in a cross-sectional survey across 12 villages, 509 under-fives from 229 randomly selected homesteads underwent anthropometry and provided a stool sample. Participant sociodemographic and health characteristics were determined by questionnaire. 419 stool samples underwent enzyme-linked immunosorbent assay (ELISA) for three markers of EED: alpha-1-antitrypsin, myeloperoxidase and neopterin. EED risk factors identified included older age, geophagy and recent acute illness. Secondly, in a birth cohort of 99 participants aged zero to nine months, 839 dual sugar absorption tests and 934 breath hydrogen tests were carried out at monthly intervals to measure EED and small intestinal bacterial overgrowth (SIBO) respectively. Stool samples were collected bi-weekly and 434 underwent ELISA for alpha-1-antitrypsin, myeloperoxidase and neopterin. Acute illness and antibiotic episodes were captured by active and passive surveillance. Breastfeeding status was recorded weekly. EED increased with age and was associated with stunting. In a multivariable model, EED was not associated with SIBO, acute illnesses, household water/sanitation/hygiene or antibiotics. In the same model, adjusted for age, EED was worse amongst those who had ceased exclusive breastfeeding, and for one EED biomarker this association was only seen during the rainy season.

Keywords: Environmental Enteropathy
Small intestinal bacterial overgrowth
Environmental Enteric Dysfunction
Tropical medicine
Childhood malnutrition
Intestinal microbiota
Advisor: Berkley, J
Doing good badly? Philosophical issues related to effective altruism

Suppose you want to do as much good as possible. What should you do? According to members of the effective altruism movement—which has produced much of the thinking on this issue and counts several moral philosophers as its key protagonists—we should prioritise among the world’s problems by assessing their scale, solvability, and neglectedness. Once we’ve done this, the three top priorities, not necessarily in this order, are (1) aiding the world’s poorest people by providing life-saving medical treatments or alleviating poverty itself, (2) preventing global catastrophic risks, such as those posed by nuclear war or rogue artificial intelligence, and (3) ending factory farming.
These claims are both plausible and striking. If correct, they should prompt a stark revision of how we approach our altruistic activities. However, the project of determining how to do the most good—as opposed to say, whether we should do the most good—has only recently, within the last ten years, become the subject of serious academic attention. Many key claims have not yet been carefully scrutinised. This is a cause for concern: are effective altruists doing good badly?
In this thesis, I critique and develop some of the latest claims about how individuals can do the most good. I do this in three areas: the value of saving lives (preventing premature deaths), how best to improve lives (making people happier during their lives), and cause prioritisation methodology (frameworks for determining which problems are the highest priorities). In each case, I raise novel theoretical considerations that, when incorporated, change the analysis.
Roughly speaking, my main conclusions are (1) saving lives is not as straightforwardly good we tend to suppose, may not be good at all, and is not clearly a priority; (2) happiness can be measured through self-reports and, based on the self-reported evidence, treating mental health stands out as an overlooked problem that may be an even more cost-effective way to improve lives than alleviating poverty; (3) the cause prioritisation methodology proposed by effective altruists needs to be moderately reconceptualised and, when it is, it turns out it is not as illuminating a tool as we might have thought and hoped.

Keywords: Hilary Greaves
moral philosophy
William MacAskill
cause prioritisation
happiness
saving lives
Peter Singer
effective altruism
Advisor: Greaves, H
Singer, P
Isolated singular points and the Gauss-Manin connection

This thesis studies the Gauss-Manin connection for the Milnor fibration of a complex hypersurface with an isolated singular point. Using the formalism developed by Brieskorn and Malgrange, we give an explicit basis, with respect to which the connection has a simple pole and its residue matrix has a manageable form. We calculate the residue for several examples. The method of calculation enables us to give some examples relevant to questions arising in Malgrange's work on the Bernstein polynomial. We also make several conjectures related to the monodromy theorem.

Keywords: Gauss-Manin
connection
points
singularities
hypersurfaces
singularity
polynomials
Bernstein
connections
singular
Fighting for the Faith: Pierre du Moulin's polemical quest

This thesis examines Roman Catholic and Reformed Protestant polemics in the early decades of the seventeenth century through the lens of the ecclesiastical activity and polemical method of Pierre du Moulin (1568–1658), with a particular focus on his treatise debate with Cardinal Jacques Davy du Perron (1556–1618). I argue that in his early polemical writings and debates, du Moulin displayed respect for the Church Fathers and church tradition but also showed a willingness to be openly critical of the Fathers when warranted. During this period, du Moulin staunchly displayed his firm ecclesiastical commitment to the French Reformed churches. However, du Moulin’s ecclesiastical activity and polemical methodology shifted after 1610 when he gained international recognition. In that year, du Moulin wrote in defence of King James VI and I of Scotland and England and inserted himself into the Oath of Allegiance controversy. After James expressed dissatisfaction with du Moulin’s handling of the Church Fathers in the volume, the French pastor softened his approach. His subsequent works, particularly those written on behalf of James, critiqued the Fathers in a more veiled manner. Du Moulin also altered his ecclesiastical activity after 1610 by becoming more ecumenical, partnering with King James in an effort to reunite Christendom. In a surprising move for a Calvinist, du Moulin initially accommodated Arminians in his plan for reunion, but shifted his position during the leadup to the Synod of Dort. Du Moulin also attempted to remain loyal to the French Reformed churches and their presbyterian government while maintaining his patronage relationship with King James, a strong supporter of episcopal polity. Though primarily a work of intellectual history, this thesis also places du Moulin’s ecclesiastical activity and polemical treatises in the broader political and ecclesiastical currents of both France and early Stuart England during the first three decades after the promulgation of the Edict of Nantes.

Advisor: MacCulloch, D