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Investigating idiomaticity in word representations
No full textIdiomatic expressions are an integral part of human languages, often used to express complex ideas in compressed or conventional ways (e.g. eager beaver as a keen and enthusiastic person). However, their interpretations may not be straightforwardly linked to the meanings of their individual components in isolation and this may have an impact for compositional approaches. In this paper, we investigate to what extent word representation models are able to go beyond compositional word combinations and capture multiword expression idiomaticity and some of the expected properties related to idiomatic meanings. We focus on noun compounds of varying levels of idiomaticity in two languages (English and Portuguese), presenting a dataset of minimal pairs containing human idiomaticity judgments for each noun compound at both type and token levels, their paraphrases and their occurrences in naturalistic and sense-neutral contexts, totalling 32,200 sentences. We propose this set of minimal pairs for evaluating how well a model captures idiomatic meanings, and define a set of fine-grained metrics of Affinity and Scaled Similarity, to determine how sensitive the models are to perturbations that may lead to changes in idiomaticity. Affinity is a comparative measure of the similarity between an experimental item, a target and a potential distractor, and Scaled Similarity incorporates a rescaling factor to magnify the meaningful similarities within the spaces defined by each specific model. The results obtained with a variety of representative and widely used models indicate that, despite superficial indications to the contrary in the form of high similarities, idiomaticity is not yet accurately represented in current models. Moreover, the performance of models with different levels of contextualisation suggests that their ability to capture context is not yet able to go beyond more superficial lexical clues provided by the words and to actually incorporate the relevant semantic clues needed for idiomaticity. By proposing model-agnostic measures for assessing the ability of models to capture idiomaticity, this paper contributes to determining limitations in the handling of non-compositional structures, which is one of the directions that needs to be considered for more natural, accurate and robust language understanding. The source code and additional materials related to this paper are available at our GitHub repository
Numerical Methods for Clear Aligner Therapy
No full textClear Aligner Therapy (CAT) was introduced by Invisalign➤ in 1999. However,
their original patents have expired, opening up a huge and growing market for clear
aligners. Advanced manufacturing techniques and computer systems enable this
appliance technology.
This thesis investigates three aspects of the computer systems side of CAT.
The first aspect is modelling the interaction between the aligner and the crown.
The second aspect is computer-assisted treatment planning. The third aspect is
modelling the interaction of the tooth root with the jaw. As these three areas are
broad, only one aspect of each is explored.
The first part presents a novel algorithm for modelling the contact between
a rigid tooth and a deformable plastic aligner. The rigid body is modelled by a
Signed Distance Function (SDF) image, whilst a regular triangle mesh models the
deformable plastic aligner. It is found that this algorithm works. It is also found
that the results are sensitive to the resolution of the SDF image.
The second part focuses on automatically determining a target dentition. Here
the definitions for the ideal dentition are researched, and an algorithm is presented.
The algorithm works by packing the teeth onto a curve so that they touch each other.
This packing works best when the full crown geometries are used to calculate the
contact between the teeth. In addition, using one of the industry standard archwires
as the curve works better than a fitted polynomial. The algorithm provides the
foundation for further algorithms.
The third part of this thesis focussed on the material properties of the
Periodontal Ligament (PDL). First, a simple bi-linear elastic material model
characterises the effect of non-linearity in the PDL. It is found that the non-linearity in
the material changes the relationship between the Centre of Rotation (Crot) and
the Centre of Force (Cf ). However, the change in the position of the Centre of
Resistance (Cres) is found to be negligible over an extensive range of materials.
Finally, an inverse modelling method was proposed to fit material models to
the PDL. This inverse modelling approach was tested in a synthetic experiment,
where the PDL was modelled using a non-linear material, and two simple material
models were fitted using the force-displacement response. The linear and bi-linear
material models were used. For the inverse modelling to succeed, the fitted material
models should accurately capture the force vs displacement and force vs stress
relationships within the PDL. The linear material is adequate if the loading is
dominated by translation. Unfortunately, typical load cases are dominated by tipping.
The bi-linear material model effectively captures both relationships. However, the
enhanced flexibility of this model requires richer data to achieve a suitable fitting.
These results proved that the inverse modelling method proposed could be used with
in vivo measurements data to find the material properties of the PDL.
Although this thesis merely scratches the surface of the field, it provides three
frameworks that may be built on: for contact modelling using SDF images, for
automatic determining of the target dentition and inverse modelling of the PDL
Evolution and Anatomy of Early Terrestrial Arthropods: Insights from the Rhynie Chert
No full textColonisation of the land is one of the defining transitions in the history of life on
Earth, fundamentally reshaping the planet’s chemical, biological, and geological
systems. Among the most significant fossil deposits for understanding this
transition is the Lower Devonian (ca. 408 Ma) Rhynie chert of Aberdeenshire,
Scotland. Preserved in extraordinary three-dimensional detail by silica sinters
from ancient hot springs, the Rhynie chert represents the earliest complex land
animal ecosystem in the fossil record. Its diverse biota includes pioneering
plants, fungi, bacteria, and many modern animal groups, such as hexapods,
arachnids, myriapods, and nematodes, providing a unique glimpse into the
world where some of the earliest unequivocal land animals took their first steps.
This thesis employs confocal laser scanning microscopy (CLSM) to
investigate the anatomical and functional adaptations of Rhynie arthropods,
addressing key questions about the evolution of arthropod terrestrialisation and
the morphological innovations that enabled life to proliferate on land. Through
detailed analyses, this research examines the functional morphology and
phylogeny of trigonotarbid arachnids, highlighting key adaptations for terrestrial
life and reaffirming their placement within or as a sister-group to
Tetrapulmonata (Chapters 2 & 3). Additionally, a comprehensive reassessment
of the enigmatic fossil Rhyniognatha hirsti revises its phylogenetic placement
and challenges its controversial status as a calibration point for insect evolution
(Chapter 4).
Chapter 1 situates the Rhynie chert in its broader evolutionary and
ecological context, outlines the challenges and opportunities inherent in
studying fossils entombed in chert, and introduces the objectives and
methodological innovations underpinning this research. Chapter 5 synthesises
the findings of this thesis, offering a discussion of the broader implications for
understanding early terrestrial ecosystems and the evolutionary history of
arthropods.
By integrating CLSM imaging with comparative morphological and
phylogenetic analyses of fossil and extant taxa, this thesis advances our
understanding of early terrestrial ecosystems and underscores the potential of
CLSM in palaeontological research.</p
Improving Demographic Insights to Enhance Conservation of the Endangered African Penguin Spheniscus demersus
No full textKnowledge of vital demographic rates is essential for understanding population dynamics and thus for effective management of species of conservation concern. For seabirds, their cryptic, extended period of immaturity and tendency to breed in remote locations across broad ranges, means estimating demographic parameters can be challenging. In this thesis, I aimed to improve our understanding of the population dynamics of a Critically Endangered seabird, the African penguin (Spheniscus demersus), to inform and enhance its conservation. I used multiple demographic datasets, including population counts, breeding success data, and capture-mark-recapture data from over 5000 uniquely marked individuals, from five important breeding colonies in the Western Cape of South Africa. First, I used multistate capture-mark-recapture models in E-Surge, then developed a Bayesian integrated population model (IPM) to derive estimates of key demographic rates. Subsequently, I investigated the effectiveness of alternative fisheries management interventions against achieving conservation objectives set out in the species biodiversity management plan, by expanding the IPM framework to incorporate a Bayesian population viability analysis (IPM-BPVA). Studies revealed important insights into the age-specific survival of African penguins: juvenile survival was low, although this improved rapidly after the first year of life and immature survival was almost comparable to that of adults. I also derived estimates of dispersal for African penguins: philopatry appeared to be the dominant strategy for breeding adults. However, natal dispersal varied across sites, and there appeared to be no considerable differences between the natal dispersal of individuals reared in the wild, or those that had been hand-reared in captivity. When projected into the future, the African penguin population was largest, and population growth rate was highest under scenarios that incorporated fishing closures at scales that protect both juveniles/immatures and non-breeding adults. The IPM-PVA also demonstrated that small-scale-scale fishing closures around breeding colonies are sufficient to reverse population declines, when implemented at sufficient scales to adequately protect the foraging grounds of breeding adults. Overall, this thesis provides important demographic insights, alongside critical evidence to inform the development of conservation interventions for the African penguin. It also demonstrates the suitability of the African penguin as a model species to address questions regarding early-life demographic traits
Optimising NHS Bereavement Care
No full textTitle of Doctoral Thesis: Optimising NHS Bereavement Care
Title of Paper 1 - Systematic Literature Review:
To what extent do grief therapies repair depression, anxiety, functional impairment, and PTSD in adults with prolonged grief? A systematic review and meta-analysis of secondary outcomes in randomised controlled trials
Abstract:
Background: A range of grief-specific psychological therapies are established as at least partially effective at reducing symptoms of ‘unresolved grief’, now termed prolonged grief disorder (PGD). However, their impact on co-morbid secondary psychological symptoms of depression, anxiety, posttraumatic stress disorder (PTSD), and functional impairment is less clear. This systematic review (SR) and meta-analysis aimed to assess how effectively these interventions alleviate secondary outcomes in bereaved adults with PGD.
Methods: Comprehensive hand-searching of existing SR’s identified randomised controlled trials (RCT’s) including relevant secondary outcome data of grief therapies targeting PGD symptoms. A systematic search was conducted across electronic databases OVID, Medline, and Web of Science to identify relevant RCT’s published after the most recent meta-analyses. Adhering to pre-defined eligibility criteria; included RCT’s involved adults (18+) with confirmed PGD, who received grief therapy delivered by or with support of a clinician, reporting on ≥1 secondary psychological outcome using standardised, validated measures. In total, 21 RCT’s were included investigating both between and within-arm comparison effect sizes (ES’s), calculated using Hedge’s G. Study characteristics, meta-analytic data, and methodological quality of trials were synthesised and analysed.
Results: Within-arm analyses revealed active treatments led to significant improvements from pre-to-posttreatment: with large, significant ESs for PGD (g=1.32), PTSD (g=1.13), depression (g=0.87), and moderate for anxiety (g=0.59). Between-arm subgroup analyses found significant ESs relative to passive comparators; large for PGD (g=0.93), borderline-large for PTSD (g=0.75), medium for depression (g=0.63), and small for anxiety (g=0.25). Relative to active comparators, significant ESs of medium and small magnitudes for PGD (g=0.61) and depression (g=0.37), were found, respectively. Small, non-significant effects were found for PTSD (g=0.14) and anxiety (g=0.18), though these outcomes had fewer active comparators available for analysis. However, significant heterogeneity was found across these outcomes.
Limitations: Across trials, methodological heterogeneity and evidence of potential publication bias were observed, particularly in PTSD outcomes. More rigorous, standardised RCT quality and bias assessment tools limited interpretability of individual study quality that may have impacted findings. Employing more advanced statistical methods including additional multi-level and moderator meta-analyses may have accounted for heterogeneous meta-analytic findings and improved rigour and generalisability of the results–which were further limited by the predominance of Western, white, female samples in included RCT’s. Furthermore, small deviations from the registered protocol are noted due to resource availability and time-constraints of completing the study.
Conclusions: The findings of this SR and meta-analysis support the efficacy of grief-specific interventions in repairing PGD symptoms whilst also alleviating associated psychological co-morbidities in adults with PGD. The limitations and heterogeneity highlight the importance of future research focusing on moderators of intervention efficacy, particularly in more diverse populations. Despite limitations, findings are clinically valuable given the recent recognition of PGD as a distinct diagnosis in diagnostic manuals – and substantiate the need to more widely integrate grief therapies into routine psychological care.
Keywords: Prolonged grief disorder; systematic review; meta-analysis, grief; anxiety; depression; PTSD
Title of Paper 2 - Empirical Study
A qualitative study exploring clients’ and therapists’ views and experiences of a pilot Prolonged Grief Therapy pathway in NHS Talking Therapies
Abstract:
Background: Prolonged Grief Disorder Therapy (PGDT) is a specialised intervention designed to treat Prolonged Grief Disorder (PGD), a persistent and debilitating grief reaction. While empirical evidence supports PGDT's efficacy in alleviating PGD symptoms, no qualitative evaluation has been undertaken. The Devon NHS Talking Therapies Service (NHS-TTS) ‘TALKWORKS’ recently implemented a pilot grief pathway incorporating PGDT as a high-intensity intervention for individuals presenting with PGD symptoms. This pilot provided a valuable opportunity to undertake the first qualitative study of PGDT in routine care.
Objective: To conduct an in-depth qualitative evaluation of PGDT, focusing on views and experiences of both clients and therapists involved in the TALKWORKS pilot. The research sought to understand perceived therapeutic impacts, mechanisms of change, barriers and facilitators to engagement, the feasibility and acceptability of PGDT in routine care settings, with a secondary aim of exploring therapist views on wider implementation in NHS-TTS.
Methods: 11 clients and 6 therapists were recruited from the pilot to participate. Qualitative interview data was analysed with a framework method to capture the nuanced experiences of both clients receiving and therapists delivering the intervention. Clinical outcome data, client satisfaction, and demographic surveys were collected to further contextualise qualitative findings.
Results: Five themes emerged: "Life Before: Stuck Grief," "Profound Changes to Wellbeing" "Experiences of PGDT," "Mechanisms of Change," and "The Grief Gap: A Distinct Therapeutic Offering." Clinical outcome and satisfaction ratings suggest PGDT is satisfactory and effective in repairing symptoms of PGD, depression, anxiety, and overall functioning.
Conclusions: Findings indicate PGDT is a highly effective and acceptable intervention for individuals with PGD. A flexible, tailored therapeutic approach is emphasised as crucial for improving outcomes. The study advocates for and considers practical implications for wider implementation of grief pathways in NHS-TTS to improve and optimise care for this currently underserved client-group.
Keywords: Complicated Grief, NHS Talking Therapies, Prolonged Grief Disorder Therapy, PGDT, Qualitative Evaluatio
Is a Non-striving Strategy Adequate for Coping with Intrusive Thoughts that Get in the Way of Being Present during Encounters with Animals?
No full textSince the emergence of the interdisciplinary field of anthrozoology, it has covered various interactions between humans and nonhuman animals (hereafter “animals”). Among these interactions, pleasurable encounters with animals who show feelings and intentions hold great appeal for people. Getting pleasure from such encounters with animals requires people to be present (especially being present to the feelings and intentions expressed by animals). However, some intrusive thoughts can get in the way of being present, and thus prevent people from enjoying their encounters with animals who show feelings and intentions.
Adopting a non-striving strategy has been proposed by some scholars as a way to cope with intrusive thoughts — to attend to intrusive thoughts with the attitude of allowing them to be what they are rather than striving to get rid of them. Some studies have found that the non-striving strategy can reduce the distress caused by intrusive thoughts, but the frequency of intrusive thoughts does not necessarily decrease. Then, the non-striving strategy seems to only partially solve the problems caused by intrusive thoughts, and does not prevent intrusive thoughts from repeatedly getting in the way of being present during encounters with animals. This leads to the research question of this thesis: Is a non-striving strategy adequate for coping with intrusive thoughts that get in the way of being present during encounters with animals who show feelings and intentions? Through investigation into this question, the aim of this thesis was to improve the understanding of the non-striving strategy as a way to cope with intrusive thoughts in the context of encounters with animals.
To that end, I chose autoethnographic methodology. Autoethnography can use researchers’ own experiences to add new voices to existing academic conversations. In this project, I reflected upon my past experiences of practising the non-striving strategy to cope with intrusive thoughts that prevented me from being present during encounters with animals who showed feelings and intentions. Through interpreting my experiences with engaging in reflexivity, I identified and clarified those intrusive thoughts that caused problems. I found that in the face of intrusive thoughts and the conflict between my eagerness to enjoy encounters with animals more often and the repetition of intrusive thoughts, the non-striving strategy served only to train me to allow them to be what they were without falling into distress, rather than to bring more enjoyment of encounters with animals. However, I also found that it was unnecessary to aspire to reduce the frequency of intrusive thoughts to enjoy encounters with animals more often. Then, rather than saying that the non-striving strategy cannot completely solve the problems caused by intrusive thoughts (i.e., interrupting the enjoyment of encounters with animals and causing distress), it is more appropriate to say that the problem that needs to be solved is just distress, with which the non-striving strategy is adequate for coping. In addition, the realisation of the above non-necessity can make it easier for one to step outside of intrusive thoughts to attend to them and allow them to be what they are as they arise repeatedly.
These findings improved the understanding of the non-striving strategy as a way to cope with intrusive thoughts in the context of encounters with animals who show feelings and intentions. Practically, these findings will mainly help someone who values the pleasure of encounters with animals but who finds that certain intrusive thoughts get in the way of being present to enjoy encounters with animals. I also suggested that the non-striving strategy could be combined with animal-assisted interventions (AAIs) as “Non-Striving AAIs,” which might be helpful to these people
Evidence of reduced birth-weight in Ukraine following the full-scale Russian invasion (dataset)
No full textThis is the dataset used for the Arbuzova et al. (2025) article "Evidence of reduced birth-weight in Ukraine following the full-scale Russian invasion"
Augmented Reality Technology for Facilitating Interactional Competence in a Chinese EFL Classroom-situated learning context
No full textThis study was informed by the action research approach involving an AR intervention, specified by Conversation Analysis and thematic analysis of video recordings of participants’ interactions and interviews. The key findings suggested that with AR implemented, participants’ IC development was prominent with the diversification and complexification of the interactional methods deployed at different levels of language proficiency, displaying the LR informed participation framework of learners in groups. Also, from the group interactions and participants’ perceptions, this study identified an AR affordance framework in language learning contexts, all of which contributed to the understanding of L2 IC development with AR implementations, the complex nature of group interactions by collaboration of learners with different LR, and the theorization of AR affordances which could further inform pedagogical implications for technological implementations
Stark effect tunable terahertz transitions in finite carbon chains
No full textHighly aligned, long polyynic chains terminated with gold clusters have been synthesized, and their use for tunable terahertz (THz) emitters is proposed. A tight‐binding model (which is arguably best suited to describe edge states in the limit of strong optical pumping) is employed to calculate the optical selection rules of gold‐capped finite‐size polyyne chains subjected to an applied electric field. The magnitude of the edge‐state gap and the strength of optical transitions across it are tunable via the Stark effect. For sufficiently long chains, electric‐field‐tunable dipole transitions between edge states occur in the highly sought‐after THz frequency range.</p
DIGIT Lab Case Study Brochure 2025
No full textLaunched in 2021, the DIGIT Lab is an Engineering and Physical Science Research Council (EPSRC) funded Next Stage Digital Economy Research Centre. Digit Lab is led by the University of Exeter, in collaboration with the University of East Anglia, Oxford Brookes University, and Royal Holloway, along with more than 30 industry partners. We are backed by over £12M in funding, focusing on accelerating digital innovation and transformation in Large Established Organisations (LEOs).
The multidisciplinary team (design engineers, computer scientists, management scholars, behavioural and social scientists) works with a broad community of academics, practitioners, and policymakers across multiple domains, delivering new research insights into digital transformation.</p