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Meteotsunami dynamics in the UK: Investigating occurrence, mechanisms, intensity, and impacts
No full textMeteorological tsunami or meteotsunami are globally occurring shallow water waves with a period of
between 2 to 120 minutes and are a result of sudden pressure changes and wind stress from moving
atmospheric systems, causing destruction and loss of life. In recent decades meteotsunami have
garnered attention, particularly within the United Kingdom (UK), however data is fragmented. Through
the presentation of three distinct but interconnecting studies this thesis aims to provide a comprehensive
framework for documenting, quantifying, and understanding meteotsunami within the UK but with a
view to global applicability, providing a valuable resource to aid in timely warnings and adaption
measures vital for communities to be better prepared to face this natural hazard.
The first study provides a standardised set of identification criteria and a comprehensive catalogue of
98 documented events between 1750 and 2022. The data showed pronounced geographical hotspots in
Southern England and Northwest Scotland, with the prevalence of winter events associated with mid-latitude depressions and summer events associated with convective activity. This thereby challenges
earlier assumptions about the seasonal and geographical distribution of meteotsunami in the UK.
The second study introduces the Lewis Meteotsunami Intensity Index (LMTI), a new five-level
framework aimed at creating a standardised methodology for quantifying meteotsunami intensity and
impacts. The data revealed a 69% predominance of moderate intensity events (Level 2), with a spatial
distribution of risk along the southern and western coasts. This trial of the LMTI serves as a prototype
for global application, thus enhancing the understanding of meteotsunami in other susceptible regions.
The final segment of this thesis investigates the potential disruption to saltmarsh vegetation from two
UK meteotsunami (2016 and 2021). By utilising high-resolution satellite imagery and employing the
Normalised Difference Vegetation Index (NDVI) data showed a minimal vegetation change (0.26 to
0.23) and a reduction in coverage of 40% in 2016 following an isolated event. However, in 2021 a
reduction in NDVI (0.44 to 0.22) and a loss of 66% coverage occurred following a series of storms and
meteotsunami
A short note on Schiffer's conjecture for a class of centrally symmetric convex domains in R^2
No full textLet Ω be a bounded centrally symmetric domain in ℝ2 with analytic boundary ∂Ω and center c. Let τ = τ(Ω) be the number of points p on ∂Ω such that the normal line to ∂Ω at p passes through c. We show that if τ < 8 then Ω satisfies Schiffer’s conjecture
Contrasting hydro‑climatic trends and drought dynamics in Ethiopia and South Africa under climate change
Get PDFClimate change profoundly impacts hydro-climatic systems, altering precipitation, temperature, and drought dynamics.
This study investigates contrasting trends in Ethiopia and South Africa under historical and future scenarios (SSP2-4.5, and SSP5-8.5) using CMIP6 datasets. The analysis encompasses national averages and regional clusters to capture both spatial
and temporal variability. In Ethiopia, annual precipitation increases by 1.2 mm/year under SSP2-4.5 and 2.5 mm/year under SSP5-8.5, potentially benefting agriculture but elevating food risks. Conversely, South Africa experiences decline in precipitation of 0.25 mm/year and 0.32 mm/year under SSP2-4.5 and SSP5-8.5, respectively, likely to exacerbate water scarcity
and compromising agricultural resilience. Both countries see substantial increases in potential evapotranspiration (PET)
and temperature extremes. Ethiopia’s PET rises by 0.67 mm/year and 0.97 mm/year, while South Africa’s PET increases
by 1.14 mm/year and 1.83 mm/year. Temperature increases in Ethiopia are more pronounced in minimum temperatures,
while South Africa shows a similar rate of increase in both maximum and minimum temperatures. Drought analysis using
SPEI and SPI indices reveals divergent trends: Ethiopia generally experiences decreased drought occurrence, severity and
frequency, whereas South Africa faces increased drought occurrences and its properties, particularly under high emissions.
These trends vary across clusters, highlighting the need for tailored adaptation strategies in each region. Despite its comprehensive approach, the study acknowledges limitations, including uncertainties in climate model projections and the need for more localized data. Understanding the interplay between hydro-climatic variables and their extremes is essential for effective adaptation. Ethiopia should strengthen food management and promote soil conservation practices, while South Africa should focus on water conservation. Both nations must integrate climate projections into planning, enhance early warning
systems, and foster public–private partnerships for successful adaptation
Variation in the pollen diet of managed bee species across European agroecosystems
Get PDFBee-mediated pollination plays a crucial role in sustaining global food production. However, while the demand for these pollination services is increasing, many bee species are in decline. To address this discrepancy, farmers use managed bee species to improve crop pollination. One key factor affecting pollination efficiency is the affinity for the crop of interest (i.e., the extent to which a bee integrates floral resources of a crop into its diet). In this study, we characterised and compared the pollen foraging preferences of three managed bee species: Apis mellifera, Bombus terrestris, and Osmia bicornis, across European agricultural landscapes and across biogeographic regions. Managed populations of each bee species were experimentally established at 128 agricultural sites growing either apple or rapeseed, in landscapes representing gradients in terms of the proportion of cropland, in eight European countries. We conducted pollen store sampling and employed palynological analyses to describe the foraging preferences of these species and to extrapolate their suitability as pollinators for both crops. Our findings reveal that A. mellifera and B. terrestris exhibited a more generalised pollen diet compared to O. bicornis, which showed stronger preference to certain pollen forage plants, but these were mainly non-crop rather than crop plants. These results question the relevance of using O. bicornis in apple orchards and rapeseed crops given their poor affinity with these crops. Overall, A. mellifera collected the highest proportion of rapeseed pollen in its diet, and A. mellifera and B. terrestris collected higher proportions of apple pollen than O. bicornis. Our findings also highlight substantial variation in the percentage of focal crop pollen in the diet across biogeographic regions, while landscape composition had virtually no impact. These results provide valuable insights for selecting the most suitable managed bee species to enhance the pollination of two key crops in Europe
Co-developing community-based participatory research (CBPR) guidelines in Hong Kong: an example of a mental health literacy promotion project
Get PDFAlthough community-based participatory research (CBPR) is context and cultural-specific, existing CBPR guidelines were developed in the West and may not be suitable for East Asian contexts given different cultural backgrounds. Moreover, most CBPR mental health literacy promotion projects have been conducted in the West, with limited examples in East Asia. Therefore, the objectives of the current study were to co-develop CBPR guidelines with stakeholders in Hong Kong and to illustrate this with an example of a mental health literacy promotion project. We conducted seven focus group discussions with seventeen older adults in the community and eleven social workers from partnering non-governmental organizations. Subsequently, we formed a panel with community stakeholders to co-analyze and co-interpret the data and findings. Using the grounded theory approach, we identified six guidelines pertinent to CBPR practice in East Asian communities: 1. Highlighting an ‘acceptance and openness’ mentality in CBPR training; 2. Navigating the hierarchical culture to facilitate an equal partnership; 3. Breaking the project into smaller action tasks to facilitate design and implementation; 4. Fostering collective harmony through team-building activities and informal gatherings; 5. Encouraging open discussion of mental health; 6. Leveraging informal networks in mental health literacy promotion. Our discussion focuses on the methodological insights of practicing CBPR in Hong Kong and its implications in East Asian communities, along with the cultural differences compared to the West
Aphasia in South Asian Languages (ASAL) project: a protocol of connected speech tasks for investigating cross-linguistic grammatical profiles in aphasia for South Asian languages
Get PDFBackground: Languages vary in their syntactic (e.g., word order in sentences), lexical (e.g., presence of specific word classes), and morphological (e.g., inflectional or derivational forms of words) properties. This cross-linguistic variation in language typology influences the manifestation of agrammatic symptoms. However, most theoretical models of agrammatism are based on English and a few European languages, limiting their generalizability. This narrow focus neglects the rich syntactic, lexical and morphological variations available in languages globally. Clinically, the lack of language-specific characteristics of agrammatic impairments limits translational potential for precise and improved diagnosis. The Aphasia in South Asian Languages (ASAL) project addresses this gap by leveraging interdisciplinary expertise and advances in connected speech methodologies and analyses. It aims to identify cross-linguistic features of agrammatic production in post-stroke aphasia across under-researched languages from two major language families: Indo-Aryan (Hindi-Urdu, Bengali) and Dravidian (Tamil, Kannada, Malayalam).
Aim: This paper presents the protocol developed as the part of the ASAL project for eliciting connected speech data to examine cross-linguistic grammatical profiles in aphasia. It outlines procedures for data collection across five connected speech genres and offers detailed guidelines for transcription, segmentation and data extraction. Additionally, it provides recommendations for linguistic analyses aimed at characterising agrammatism and grammatical deficits, while also accounting for cross-linguistic variation.
Methods & Procedures: The protocol was designed for cross-sectional data acquisition from cohorts of people with post-stroke aphasia meeting the criteria of ‘agrammatic by clinical standard’ and neurologically unimpaired speakers in each of the five languages. Data collection procedures are detailed for five connected speech genres – personal narrative, procedural task, image sequence, novel story narrative and picture description – with multiple exemplars in each. Additional data include demographics, aphasia type and severity, and cognitive assessments (e.g., verbal fluency, inhibition, memory span, shifting, cognitive screen). The protocol provides guidance for transcription, data extraction and recommendations for cross-linguistic analyses, along with results of preliminary analyses.
Conclusion: The ASAL project is a pioneering initiative investigating agrammatism in linguistically diverse, under-studied South Asian clinical populations. This protocol enables researchers to conduct cross-linguistic studies and develop culturally and linguistically tailored clinical tools. Specifically, it supports: 1) the identification of agrammatic features in narrative speech across languages; 2) the development of clinical checklists for identifying grammatical impairments. This protocol is uniquely positioned to facilitate effective comparisons between universal and language-specific grammatical patterns across a broad spectrum of languages and language families, including multilingual populations and diverse clinical conditions
Social robots: an investigation into technological adoption
No full textIn an era of rapid technological advancements, social robots have become
increasingly prevalent across various sectors (Vishwakarma et al., 2024). As of
June 2023, the UK government committed £2.4 billion to implementing AI and
robotic technologies, including the use of social robots within the NHS (Hooson
and Pratt, 2024). Despite their growing global use in industries such as
healthcare, airports and entertainment (Moriuchi and Murdy, 2024), the UK has
limited exposure to social robots (IFR, 2022).
Prior research within human to robot interaction literature had identified several
challenges that warrant further investigation. These challenges include the
adaptation of existing technological adoption frameworks and to further
understand the roles of risks, motivations and users’ intentions to accept new
technologies (Chatterjee et al., 2023). Societal concerns of emerging
technologies remain a prominent issue, with individuals still reluctant to accept
social robots primarily due to issues related to risks and privacy (Liu and
Hancock, 2024; Lutz and Tamo-Larrieux, 2020; Lenca and Fosch-Villaronga,
2019; Pavlou, 2001). This research offers new insights into how various factors
influence users' intentions to adopt social robots, by modifying the most up-to-date version of the latest technology adoption framework through employing
the UTAUT2. Another contribution of this thesis resided in the restructuring of
the UTAUT2 model to explore alternative pathways through which users'
intentions to accept social robots are formed. By testing these varying pathways,
this research has offered an alternative understanding of how varying factors
interact and influence users' behavioural intentions. This approach moves
beyond the traditional inclusion of antecedent variables towards behavioural
intentions, which has been a limitation within adoption frameworks over the
past two decades
Anhedonia and depression in youth: real-world and computational evidence of impaired reward processing
Get PDFBackground: Major Depressive Disorder (MDD) is the leading cause of disability in young people,
and predicts increased risk of suicide and unemployment in adulthood. Anhedonia, the loss of
interest and pleasure, is a core symptom of depression. Impairments in reward processing sub-components (anticipation, motivation, consummatory and learning) are thought to underlie
anhedonia symptoms. Discovering novel reward-based treatment targets in young people could
protect against poor outcomes in adulthood.
Ecological momentary assessment (EMA) questionnaires examine reward processing in real-life,
removing recall biases. Previous EMA studies have demonstrated deficits in anticipatory and
consummatory pleasure in depression vs controls. Studies have also reported lower mood in
depressed individuals, i.e. lower positive affect (PA) and elevated negative affect (NA). The Mood
brightening (MB) effect has been observed, where positively-rated events lead to greater increases
in PA and greater reductions in NA in depression vs controls. Lab-based experimental tasks
demonstrate depressed individuals less frequently choose to exert effort for rewards, suggesting
deficits in motivation. Probabilistic learning tasks show individuals failing to develop response biases
to more rewarding choices, suggesting reduced exposure to rewarding experiences in depression.
Leisure activities and social company are known to protect against depression, but inactivity and
social isolation are more prevalent. Understanding how to increase compliance with rewarding
activities would improve outcomes in depressed youth. However, how to increase enjoyment and
engagement in pleasurable activities remains unclear, and the MB effect of such activities remains
scarcely examined. Lastly, experimental tasks have rarely combined learning to maximize rewards
with exerting effort to attain them, which closely capture the real-life dynamics of reward processing.
Methods: Young people (16-25 yrs old) were recruited from local schools and the university.
Depression symptoms were measured using the Mood and Feelings Questionnaire (MFQ) and the
Beck Depression Inventory-II (BDI). Anhedonia symptoms were measured using the Temporal
Experience of Pleasure Scale (TEPS), the Snaith-Hamilton Pleasure Scale (SHAPS), and the
Anhedonia Scale for Adolescents (ASA).
The EMA protocol adapted from Edwards et al. (2018), presenting seven daily assessments for 6
days on smartphones. Participants selected from multiple choices for physical activities and
company, then rated anticipation (anticipatory pleasure, expectation) and motivation (preference,
interest) for planned activities, enjoyment of current activity, and mood (PA, NA) on 7-point Likert
scales. The physical activities were categorised as Leisure (relaxing, exercising, other leisure
activities) or Functional (work/school, hygiene, etc.), and company as Social (friends, family, partner)
or Non-Social (alone).
In Paper 1, participants (N=80; 2,316 assessments) were classified by depression severity: high
(HD, MFQ ≥ 27, n=42), moderate (MD, MFQ 16–27, n=16), and controls (C, MFQ ≤ 16, n=22).
Multilevel models examined time-lagged relationships: how anticipation and motivation (t-1) predict
the enjoyment and engagement in Leisure activities and Social company (t). Linear regressions
examined how depression symptoms predict time spent in activities. Paper 2 used EMA mood data
from participants (N=71; 2,177 assessments). Affective reactivity was measured as change from two
baselines: mean affect and affect (t-1). Multilevel models examined how depression and anhedonia
symptoms (MFQ, ASA) predicted reactivity, and how context (Leisure, Social) moderated this
relationship.
For Paper 3, an online reward and effort learning task was adapted from Frey et al. (2023).
Participants (N=155) chose between two shapes, each requiring effort exertion (high/low button
presses) to acquire rewards (puppy/dog image). Reward and effort learning blocks, 25 trials each,
required participants to maximize reward or minimize effort, respectively. Outcome contingencies
were 25/75%. Q-learning equations modelled choice data with parameters (learning rate,
explore/exploit parameter) capturing aspects of learning. Correlations examined relationships of
anhedonia (SHAPS, TEPS) with subjective ratings of rewards (liking, wanting, effort willingness),
task performance, and parameter values. Corrected for multiple comparisons.
Results: Paper 1 revealed young people with higher depression symptoms spent less time on
work/school and hygiene. When planned (t-1) and actual activities (t) matched, higher anticipatory
pleasure predicted greater engagement and more enjoyment from leisure activities and social
company in HD group (Paper 1). Paper 2 revealed that engaging in leisure activities or social
company predicted greater decreases in NA at higher depression symptoms, but not PA.
As expected, Paper 3 revealed lower liking, wanting and effort willingness for puppy images with
increasing anhedonia. Further, lower effort and reward learning accuracies correlated with
increasing consummatory anhedonia. Computational modelling revealed that higher temperature
values may underlie this, suggesting over-exploration of less rewarding options.
Limitations: As the sample consisted mostly of highly-educated females, generalizability of these
findings is limited. Seven questionnaires per day restrict the number of time-lagged relationships that
can be captured. Preference for puppy and dog images may vary, which may influence results.
Conclusions: Episodic future thinking (EFT) is shown to enhance anticipatory pleasure. Future
studies should examine if EFT increases enjoyment and engagement in leisure activities and social
company in depression. These activities are likely to elevate mood by reducing NA at higher
depression symptoms, so managing negative emotions could be encouraged in depressed
individuals. Exploring how social rewards are processed using the reward and effort learning task
and EMA is encouraged, as these are more salient for young people. Studies are novel - a strength
but few previous studies to evaluate findings against. Replication of all studies in larger samples is
suggested