VictorJuiz/thesis huggingface dataset:
Comparability of science assessment across languages: the case of PISA science 2006

In this research, I investigated the extent to which language versions (English, French and Arabic) of the same science test were comparable in terms of item difficulty and demands. I used PISA science 2006 data from three countries (respectively, UK, France and Jordan). I argued that language was an intrinsic part of the scientific literacy construct, be it intended or not by the examiner. The tight relationship between the language element and the scientific knowledge makes the language variable inextricable from the construct. This argument has considerable implications on methodologies used to address this question. I also argued that none of the available statistical or qualitative techniques were capable of teasing out the language variable and answering the research question.
In this thesis, I adopted a critical evaluation and empirical methods, using literature from various fields (cognitive linguistics, psychology, measurement and science education) to analyse the test development and design procedures. In addition, I illustrated my claims with evidence from the technical reports and examples of released items. I adopted the same class of models employed in PISA, the Rasch model, as well as differential item functioning (DIF) techniques to address my question empirically.
General tests of fit suggested an overall good fit of the data to the model with eleven items out of 103 showing strong evidence of misfit. Various violations to the requirements of the Rasch model were highlighted. The DIF analysis indicated that 22% of the items showed bias in the selected countries, but bias balanced out at test level. Limitations of the DIF analysis to identify the source of bias were discussed. Qualitative approaches to investigating question demands were examined and issues with their usefulness in international settings were discussed. A way forward incorporating cognitive load theory and computational linguistics is proposed.

Keywords: science assessment
translation
adaptation
language
PISA
Advisor: Baird, J
McNicholl, J
Optimizing selectivity in heterocycle C-H functionalization through computational design

This thesis describes the application of quantum chemical methods to understand Pdcatalyzed C-H activation of aromatic and heteroaromatic molecules, with a view to establishing the factors that enable predictions of site-selectivity to be made. The first chapter introduces palladium catalyzed C-C bond formation and the synthetic field of direct (C-H/C-X) and oxidative cross-couplings (C-H/C-H), the postulated mechanisms of C-H activation, and the theoretical background to the project. The focus of Chapter 2 is the mechanism and site-selectivity of Pd catalyzed direct arylation of N-methyl indole. The mechanism is shown to proceed via a concerted metalation deprotonation of N-methyl indole followed by transmetalation with PhB(OH)2. Importantly, this second step determines the C2 regioselectivity observed experimentally, and the key transition structure is stabilized through a π-polar bond between AcOH and the C2-C3 π system of indole.
In Chapter 3 we apply DFT calculations to examine the mechanism of Pd catalyzed activation of N-methyl indole in an oxidative cross-coupling. Calculations predict the mechanism to proceed via initial C-H activation of the indole followed by C-H activation of benzene. Concerted metalation deprotonation is favoured, and assisted by coordinating solvent molecules. Alternative mechanisms, previously postulated in the literature, are calculated and do not support observed experimental results.
We extend our examination into the C-H activation and oxidative arylation of N-acetyl indole by investigating a co-catalyst Pd/Cu system in Chapter 4. Calculations demonstrate that a Pd-Cu dimer is energetically viable and leads to initial cleavage at C3. The regioselectivity of the mechanism is determined through the subsequent C-H activation of benzene and completed with a facile reductive elimination step.
In Chapter 5 we apply a combination of DFT and kinetic modelling on the trifluoroacetic acid (TFA) tuned homocoupling of benzene and the heterocoupling of benzene and anisole. Concentration terms are applied with the implementation of transition state theory to develop kinetic models. Various catalytic models are investigated to show that Pd(OTFA)2, formed at high concentrations of TFA, favours homocoupling, while at lower TFA concentrations the catalytic species will be Pd(OAc)2-TFA which favours heterocoupling.
Finally, Chapter 6 presents DFT studies on the Pd-catalyzed homocoupling and chemoselectivity of p-xylene. Pd(OTFA)2 is computed to display greater activity than Pd(OAc)2 in oxidative C-H cross coupling. Benzylic (sp3) C-H activation of p-xylene is computed to be relatively difficult compared with sp2 activation, but can nonetheless occur via an eight membered intermolecular deprotonation transition state.

Advisor: Paton, R
Vision-based flight control and stabilisation in hawkmoths

Insects are inherently unstable and therefore rely on sensory feedback in order to maintain flight control and stability. This thesis focuses on how the hawkmoth Manduca sexta uses visual feedback to control and stabilise flight. The analysis is based on extensive sampling of the optomotor responses. I use a virtual reality flight simulator to measure the total moment that the moths generate in response to oscillating wide-field stimuli. The visual stimuli simulate rotations of different amplitudes and frequencies about six different body axes. The moment responses depend upon stimulus amplitude, so are fundamentally non-linear. Nevertheless, for a fixed and suitably small stimulus amplitude, it is possible to fit a linear PID-controller with time delay to each of the optomotor responses. The analysis shows that the moths rely on proportional and integral feedback of angular velocity, with different time delays about different rotation axes. This varying time delay prevents spatial superposition of the optomotor responses to lateral rotational stimuli, meaning that there is no general control law that predicts the responses to an arbitrary lateral stimulus. By combining these empirically derived vision-based flight controllers with linearised flight dynamic models of hovering M. sexta, I evaluate their performance in providing flight stability. This analysis suggests that visual feedback is sufficient to stabilise disturbances associated with rotational stimuli about the horizontal roll and dorso-ventral axes, but is insufficient to stabilise disturbances associated with rotational stimuli about the pitch axis, vertical yaw axis, and longitudinal body axis. The time delay of the optomotor response has a substantial influence on the superposition of the measured optomotor responses, and strongly affects the predicted flight stability. The findings presented in this work have implications for understanding not only the mechanisms and functionality of flight control in hawkmoths, but also the results of past and future investigations into vision-based flight control in insects and flapping-wing air vehicles.

Advisor: Taylor, G
Characteristic functions of path signatures and applications

The main object of study in this work is the extension of the classical characteristic function to the setting of path signatures. Our first fundamental result exhibits the following geometric interpretation: the path signature is completely determined by the development of the path into compact Lie groups. This faithful representation of the signature is the primary tool we use to define and study the characteristic function.
Our investigation of the characteristic function can be divided into two parts. First, we employ the characteristic function to study the expected signature of a path as the natural generalisation of the moments of a real random variable. In this direction, we provide a solution to the moment problem, and study analyticity properties of the characteristic function. In particular, we solve the moment problem for signatures arising from families of Gaussian and Markovian rough paths.
Second, we study the characteristic function in relation to the solution map of a rough differential equation. The connection stems from the fact that the signature of a geometric rough path completely determines the path's role as a driving signal. As an application, we demonstrate that the characteristic function can be used to determine weak convergence of flows arising from rough differential equations.
Along the way, we develop tools to study càdlàg processes as rough paths and to determine tightness in p-variation topologies of random walks. As a consequence, we provide a classification of Lévy processes possessing sample paths of finite p-variation and determine a Lévy-Khintchine formula for the characteristic function of the signature of a Lévy process.

Keywords: Stochastic flows
Lévy processes
Expected signature
Advisor: Lyons, T
PEK homo and copolymers via dispersion polymerisation

This thesis is concerned with the development of the Ketonex dispersion process in order to reliably and reproducibly produce PEKK dispersions with controlled properties, together with the modification of pre-existing process parameters to achieve a range of particulate PAEK copolymers. Specific emphasis was placed on industrial considerations, pre-commercial scale-up and addressing potential materials applications.
Chapter 1 explores well established methods for the production of PAEKs by both nucleophilic and electrophilic routes. General materials properties are described, and structure-property relationships are discussed.
Chapter 2 describes in detail the process parameters associated with the Ketonex dispersion process. Parameters are discussed on a laboratory scale and are related to scale-up, industrial and commercial considerations.
Chapter 3 evaluates the production of PEKKs with a range of T:I ratios by the dispersion process. The PEKKs are analysed using a range of techniques and are compared to literature data for process evaluation.
Chapter 4 discusses the theory behind the action of the benzoic acid dispersant used in the dispersion process, which results in the production of fine particulate PEKK. A hypothesis involving the nucleation of polymerisation by aluminium benzoate is proposed.
Chapter 5 demonstrates how the dispersion process can be modified to produce a range of PAEK copolymers. The incorporation of imide and sulfone co-monomers are evaluated in detail, while a selection of alternative monomers undergo preliminary evaluation.
Chapter 6 addresses an epoxy toughening application. Amine end-capped PAEKs are produced by the dispersion process by in situ functionalisation. A protected end-capper is devised, its attachment and deprotection confirmed through a model compound approach and is successfully applied to the polymerisation system.

Advisor: Moloney, M
Towle, I
Plasticity-induced fatigue crack closure: an investigation using digital image correlation

The present work demonstrates the practical application of digital image correlation (DIC) in measuring near tip displacement fields of fatigue cracks in 6082 T6 aluminium alloy. The experimental work is focused on building from recent work done by de Matos and Nowell to directly measure fatigue crack closure with surface displacements obtained through DIC analysis. In this work, similar experiments are reproduced with extended DIC analysis and further work is performed using images obtained through in-situ SEM testing. MATLAB codes based on an existing open source program have been developed to fit images together for crack length measurements and efficiently obtain surface displacement data for a large number of points around the crack tip. In this work, near tip displacement data is used for comparison with two crack tip deformation models. The first assumes simple elastic deformation and a reasonable agreement is obtained during constant amplitude loading, although a residual stress intensity caused by the plastic wake exists, giving rise to crack closure. The other model analysed is a basic elastic-plastic assumption, proposed by Pommier and colleagues. The results during constant amplitude loading are similar, but with a slightly improved fit from the elastic model. However, a single overload cycle applied to a specimen produces significant plasticity at the crack tip and the variation in crack tip plastic displacement, represented by the second term in Pommier's model, becomes significant. Effects of load history are captured by the values of this term and the determined stress intensity factor. The relationship between these parameters and crack growth behaviour before and after an overload is investigated and related to the levels of crack closure observed. The in-situ SEM testing produced images with high resolution and magnification allowing for detailed displacement analysis and further work using this imaging method is discussed.

Advisor: Nowell, D
Sheaf-theoretic methods in quantum mechanics and quantum information theory

In this thesis we use the language of sheaf theory in an attempt to develop a deeper understanding of some of the fundamental differences - such as entanglement, contextuality and non-locality - which separate quantum from classical physics.
We first present, based on the work of Abramsky and Brandenburger [2], how sheaves, defined over certain posets of physically meaningful contexts, give a natural setting for capturing and analysing important quantum mechanical phenomena, such as quantum non-locality and contextuality. We also describe how this setting naturally leads to a three level hierarchy of quantum contextuality: weak contextuality, logical non-locality and strong contextuality. One of the original contributions of this thesis is to use these insights in order to classify a particular class of multipartite entangled states, which we have named balanced states with functional dependencies. Almost all of these states turn out to be at least logically non-local, and a number of them even turn out to be strongly contextual. We then further extend this result by showing that in fact all n-qubit entangled states, with the exception of tensor products of single-qubit and bipartite maximally-entangled states, are logically non-local. Moreover, our proof is constructive: given any n-qubit state, we present an algorithm which produces n + 2 local observables witnessing its logical non-locality.
In the second half of the thesis we use the same basic principle of sheaves defined over physically meaningful contexts, in order to present an elegant mathematical language, known under the name of the Topos Approach [62], in which many quan- tum mechanical concepts, such as states, observables, and propositions about these, can be expressed. This presentation is followed by another original contribution in which we show that the language of the Topos Approach is as least as expressive, in logical terms, as traditional quantum logic. Finally, starting from a topos-theoretic perspective, we develop the construction of contextual entropy in order to give a unified treatment of classical and quantum notions of information theoretic entropy.

Keywords: sheaves
contextuality
spectral presheaf
contextual entropy
Advisor: Abramsky, S
Doering, A
Coecke, B
Above and below the surface: Two models of subnational autonomies in EU law

This thesis examines the relation between subnational autonomies, that is to say regional and local authorities and the norms they create, and European Union law. The existence of local and regional autonomies within the various Member States of the EU is a factual truth. We know that they exist and co-exist with other levels of public authority, themselves generating norms. Yet, on its surface European Union law does not devise any substantive understanding of such autonomies. This stands in stark contrast to the relation between the Member States and the EU, which is governed by a complex catalogue of Treaty rules. As a consequence of European integration, however, subnational autonomies and EU law do interact, so that the latter cannot simply ignore the existence of the former.
This thesis sets out to determine the contours of their mutual relation through an analysis of EU procedural and substantive law. It uncovers that the relation between subnational autonomies and EU law is multifarious and diverges depending on whether we look at the surface of EU law, that is to say the Treaties, or whether we look below its surface, at the Court of Justice's rich case law or soft law instruments of the Commission. I map this conclusion through a modelling approach, relying on what I term the 'Insider Model' and the 'Outsider Model' respectively. These models underline that, in some areas of EU law, SNAs are seen to be outsiders to the project of European integration whereas other areas recognise SNAs and especially their norms to be the insiders of that project. The coexistence of both models forces us intellectually to rearrange things. It challenges our 'constitutional imagination'. The key to understanding the coexistence of both models can be found in the evolution of EU law itself. While the Outsider Model remains attached to the public international law origins of the EU Treaties, the Insider Model captures the reality that not only States and citizens, but also SNAs, are integrated into the EU legal order.

Advisor: Fisher, L
Weatherill, S
Combustor and turbine aerothermal interactions in gas turbines with can combustors

As the research into the improvement of gas turbine performance progresses, the combustor- turbine interface becomes of increasing importance. In new engine designs components come closer together and the study of the combustor and turbine interactions can prove to be valuable for the improvement of the aerothermal performance of the vane.
This thesis presents an experimental and numerical investigation of the aerodynamic and heat transfer aspect of the interactions between the combustor and the nozzle guide vane. In the gas turbine studied the trailing edge of the combustor transition duct wall is found upstream of every second vane. In the experimental measurements carried out in a purpose-built high speed experimental facility, the wake of this wall is shown to increase the aerodynamic loss of the vane. On the other hand, the wall alters secondary flow structures and has a protective effect on the heat transfer in the leading edge-endwall junction, a region that has proven to be detrimental to component life. The effect of different clocking positions of the vane relative to the combustor wall are tested experimentally and shown to alter the aerodynamic field and the heat transfer to the vane. The experimental methods and processing techniques adopted in this work are utilized to highlight the differences between the different cases studied.
A new concept of using the combustor wall to shield the nozzle guide vane leading edge is introduced, followed by a proposed design that is numerically analysed, including a new cooling system. This uses continuous cooling slots on the upstream combustor wall to cool the vane leading edge. Coolant to the endwalls is provided from continuous slots on the combustor-turbine interface. The reduction of secondary flow through the removal of the horseshoe vortex in the new design results in improved cooling of the endwalls, with a higher average adiabatic effectiveness than in the original case, using the same coolant mass flow rate. The vane surface and suction side are also successfully cooled using less air than that required for a showerhead.
The new vane is tested in the experimental facility. The improved aerodynamic and thermal performance of the shielded vane is demonstrated under engine-representative inlet conditions. The new design is shown to have a lower average total pressure loss than the original vane for all inlet conditions. The heat transfer on the vane surface is overall reduced for all inlet conditions and the peak heat transfer on the vane leading edge-endwall junction is moved further upstream, to a region that can be effectively cooled from the upstream cooling slots on the combustor wall trailing edge and the endwalls.

Keywords: secondary flow
experimental
heat transfer
aerodynamics
numerical
nozzle guide vane
Advisor: Rosic, B
Auger electron radionuclide therapy utilising F3 peptide to target the nucleolus

F3 is a 31 amino acid peptide that possesses tumour homing capability and binds to nucleolin (NCL) expressed on the cell surface of malignant cells. Exposure of osteosarcoma (U2OS) cells to F3 peptide was found to shift the distribution of NCL and nucleophosmin (NPM) from the nucleolus to the nucleoplasm, and increase the level of Ki-67 in the nucleoplasm. 111In-labelled F3 (111In-DTPA-F3) was successfully radiosynthesised and was found to be significantly radiotoxic to MCF7, HCT116, MDA-MB-231/H2N, H322 and MDA-MB-435 cells, but not U2OS cells. 111In-DTPA-F3 was shown to be taken up, and to deposit radiation dose, in the nucleolus. The level of cell kill produced by 111In-DTPA-F3 was highly variable (19 fold range in surviving fraction) depending on the malignant cell line, and was correlated with the localisation of cell-bound 111In-DTPA-F3 in the nucleus. The induction of γH2AX foci by 111In-DTPA-F3 was found to be determined by the volume of the nucleolus. In conclusion, 111In-DTPA-F3 is a promising Auger electron-emitting radiotherapeutic agent that targets the nucleolus, the radiosensitivity of which may vary depending on the malignant cell line.

Keywords: DNA damage
Nucleolus
Cancer
Auger electrons
Advisor: Vallis, K
Cornelissen, B
Investigation of the OS-9/Grp94 interaction and its role in Endoplasmic Reticulum-Associated Degradation (ERAD)

Proteins that misfold or are improperly assembled in the endoplasmic reticulum (ER) are exported to the cytosol to be degraded via the ubiquitin-proteasome pathway in a process termed ER-associated degradation (ERAD). The ER resident lectin OS-9 occupies a central role, linking recognition to the delivery of aberrant proteins to the membrane-embedded SEL1L/Hrd1 ubiquitin-ligase complex. Additionally, OS-9 interacts with Grp94, the ER-resident Hsp90 family member, in a manner that is mutually exclusive of its interaction with SEL1L. To further characterise the complexes formed by OS-9 with SEL1L and Grp94, an extensive series of OS-9 truncations/deletions were generated and the resulting co-precipitation profiles compared. It was found that OS-9 interacts with Grp94 in the ER lumen and involves the C-terminal domain of OS-9. More precisely, a 65 a. a. region (OS-9443-507) is necessary for OS-9/Grp94 binding, which was designated the 94BR (Grp94 binding region). Naturally occurring point mutations and alternative splice variants within this region were compromised for binding to Grp94 but not SEL1L or substrate, indicating a highly specific interaction. A melanoma cell line derived from a lymph node metastasis and homozygous for a somatic OS-9 mutation (P446L) exhibited an increased rate of growth when compared to a parental counterpart with one wild type allele, suggesting that disruption of the OS-9:Grp94 interaction may confer an activity that favours tumour progression. These studies point toward functional consequences when OS-9 partitioning between Grp94 and SEL1L is altered.

Advisor: Christianson, J