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Shelled shut-ins: a conditional escape task showing perceptual awareness in hermit crabs
No full textSentience is an increasingly popular topic in animal welfare and behavioural research. However, studying sentience can be difficult and contentious. Sentience has frequently been associated with ‘feelings’ and ‘subjective states’ not directly accessible to human observers; thus, investigating awareness in animals could be an alternative approach. Frameworks of awareness have been developed for the experimental examination of cognitive capacities that might underpin ‘feelings’ as affective states and subjective experiences. Using a framework of four hierarchically arranged levels of awareness (that is, perceptual, cognitive, assessment and executive), the awareness of an intertidal crustacean, the common hermit crab, Pagurus bernhardus , was assessed. Inspired by recent work on cognitive abilities and task solving in terrestrial hermit crabs, a series of four experiments was designed to test the ability of P. bernhardus to solve a simple conditional task: if the crab changes its shell, then it can escape confinement. Crabs were exposed to different levels of confinement, including complete confinement, confinement requiring shell changes for escape, confinement requiring no shell changes for escape and no confinement. Apart from testing crabs in the absence of an external motivation (experiment 1), crab responses were tested in the presence of food (experiment 2), an additional shell (experiment 3) and under hypoxic conditions (experiment 4) to ensure that individuals were motivated to escape. Crabs were more likely to escape confinement if they did not have to change shells. Sequence analysis of the behavioural patterns of crabs revealed that they are not tactically assessing different components of their confinement to aid in task solving. Collectively, these experiments indicated that P. bernhardus displays perceptual awareness without evidence of insight or forward planning
Morphodynamics of a composite barrier system, Westward Ho!, North Devon, UK
No full textUnderstanding and predicting the morphodynamic evolution of gravel barrier systems is essential for coastal management, as these features provide natural protection for infrastructure and ecosystems. This study uses the composite gravel barrier system of Westward Ho!, south west England, characterised by a sandy intertidal region and a gravel high tide ridge, to quantify the morphological behaviour of this barrier system and link the dynamics to the external forcing, notably sea-level rise and waves. Since 1887, the barrier has retreated by 97 m, with an average retreat rate of 0.71 m yr−1. Over the period 2007–2024, the system lost approximately 216,000 m3 of sediment, equivalent to 3.6 m3 m−1 yr−1. It is suggested that most of this material was transported to a beach-dune system north of the barrier, across an estuary. Over the past two decades, the retreat rate of the southern section has slowed to 0.18 m yr−1, while the retreat rate of the northern section has increased to 2.39 m yr−1. This suggests segmentation is occurring, with the southern end becoming swash-aligned and the northern end drift-aligned. Morphological changes did not strongly correlate with SLR or wave power (cross-shore or longshore). The low-tide shoreline appears near equilibrium with prevailing wave direction, but the gravel ridge is slightly misaligned, suggesting net northward sediment transport. Given current trends, the barrier is expected to continue retreating and losing sediment for several decades. However, a comprehensive understanding of the system\u27s future behaviour requires development of a mixed-sediment morphodynamic model
Exploring and Critiquing Corporate Law Practice in Nigeria: Legal Essays in Corporate Governance, Directorship, Taxation, Business Vehicles, and Other Business Combinations
No full textThis integrative work comprised seven doctrinal peer-reviewed publications produced between 2020 and 2022. The publications aimed to enhance understanding of the dynamics and regulatory complexities in corporate governance (CG), directorship, taxation, business vehicles, and other business combinations in Nigeria. The publications explored six important facets of corporate law practice in Nigeria, namely (i) the challenges and prospects of the Limited Liability Partnership (LLP) and the Limited Partnership (LP) in Nigeria (ii) the potential impact of CG in Nigeria (iii) the efficacy of one-person companies in Nigeria (iv) the legal impact of the Finance Act 2019 on taxation, mergers, and other business combinations in Nigeria (v) existing frontiers of directorship in Nigeria and (vi) the regulatory and jurisprudential frameworks for Incorporated Trustees in Nigeria. This integrative work presents the publications in reverse chronological order, with the most recent (Publication 7) appearing first, followed by the least recent (Publications 6 through 1). Corporate law practice is significant in Nigeria because it serves as a vital mechanism for fostering economic development and enhancing investor confidence. It provides a regulatory climate for transparent and accountable business operations. The publications addressed critical gaps in knowledge concerning the laws regulating LLPs and LPs in Nigeria, CG practice, and the operation of one-person companies in Nigeria. Drawing comparative insights from India, Singapore, South Africa, and the UK, they also contributed original perspectives on addressing the impact of the Finance Act 2019 on taxation, mergers, and other business combinations in Nigeria. Additionally, the works expanded the discourse on directorship and proposed reforms to the legal regime governing incorporated trustees in Nigeria. Notably, they identified the jurisprudential basis for regulating incorporated trustees under Nigeria’s Companies and Allied Matters Act 2020. They also offered recommendations for resolving the tensions arising from the Federal Government’s regulatory role, especially concerns related to section 839(1), which allows the Corporate Affairs Commission to suspend trustees under certain conditions. Collectively, while each of the seven publications individually contributes to the body of knowledge, together they illuminate six key aspects of corporate law practice in Nigeria. Although some recommendations from these publications have been implemented into Nigeria’s corporate law practice, others remain unimplemented. This integrative work draws on the latter to propose targeted suggestions essential for improving Nigeria’s corporate law in the areas examined
Tumour Treating Electric Fields for non-invasive Treatment of Glioblastoma
No full textGlioblastoma is an aggressive and fatal cancer with a median overall survival of just 15 months. Tumour Treating Fields (TTF) is a non-invasive treatment which uses alternating electric fields to disrupt mitosis. Clinical trial data demonstrated a 4 month gain in overall survival with a combination of TTF and standard chemotherapy, yet studies investigating the effects of TTF as a monotherapy are underexplored. This study optimises TTF therapy using the model organism Drosophila melanogaster and live confocal microscopy. Drosophila is a suitable model for studying TTF parameter optimisation in a high throughput manner due to the synchronous and rapid rate of embryonic cell division in a non-cancerous model. Additionally, the well characterised Drosophila brain tumour model (brat) was used in this study to investigate the effects of TTF on brain tumours in living larvae. Using live confocal microscopy, TTF parameters were optimised to induce abnormal mitotic phenotypes in 100 percent of healthy Drosophila embryos, without impacting nervous system function. In the Drosophila brain tumour model and healthy cellularised embryos, TTF caused a duration dependent arrest of metaphase. TTF had no affect on the percentage of EdU positive cells in Drosophila brain tumours or in human patient-derived glioblastoma stem cells (GSCs) but EdU incorporation is reduced in immortalised glioma cells (U87MG). Conversely, Ki67 levels are reduced in GSCs but are unchanged in U87MG cells, suggesting cell type specific responses and sensitivity to TTF. Additionally, TTF treatment increases cell death in U87MG cells. This data provides evidence that TTF alone can work as an anti-cancer therapy and that it is a highly effective, safe cancer treatment
Does increasing human impact across the holocene result in simplification of vegetation composition and diversity across Europe? A pollen-based spatio-temporal approach
No full textLand use and climate change are the primary drivers of current biodiversity loss, but have had different impacts on biodiversity across the Holocene epoch. To enhance our understanding of current changes in diversity and its impact on ecosystem functions, knowledge of long-term interactions between vegetation diversity, land use change, and climatic change is crucial. Grid-cell estimates of quantified regional vegetation cover (RVest) based on pollen data from 1607 sites across Europe, transformed using the REVEALS (Regional Vegetation Estimates from Large Sites) model, have been used to explore spatiotemporal changes in vegetation and regional diversity during the Holocene (25 time windows covering the period from 11.7 ka cal BP to present). Space-time constrained clustering of the RVests identified six dominant vegetation types (VTs): Mediterranean vegetation, open vegetation, Abies-Fagus forest, broadleaved mixed forest, coniferous mixed forest, Betula woodland, whose spatial extent changes over the Holocene. The study explored REVEALS α-diversity (richness of taxa, richness of abundant taxa, and evenness) within each grid cell as well as spatial REVEALS β-diversity (spatial variations in composition within one time frame) and turnover (temporal variation in composition within one grid cell) within each vegetation type. Changes in location, size, taxa composition, and REVEALS diversity of the vegetation types characterised four phases during the Holocene. The first (pioneer: 11.7–9.2 ka cal BP) and second (summer-green forest: 9.2 ka to 5.2 ka cal BP) phases generally showed higher REVEALS β-diversity and lower REVEALS evenness. The third phase (mixed semi-natural forest: 5.2 ka to 1.7 ka cal BP) is characterised by expansion of open vegetation and reflects increased human impact on the environment caused by increasing use of land for agricultural production. The final phase (from 1.7 ka cal BP) saw rapid transformations: open vegetation not only expanded, but also shifted in composition, with major increases in cereals and other anthropogenic indicators. This signals a clear intensification of land-use impact over the last two millennia. Across central Europe, vegetation became increasingly homogenised, dominated by a few widespread species. As a result, both REVEALS evenness and spatial β-diversity plummeted—marking a profound loss of ecological complexity. In short, human-driven landscape openness did not simply reshape the vegetation—it rewrote the rules of diversity across the continent
High frequency emergency department use and heterogeneity of reasons for attendance by children and young people: a retrospective cohort study
No full textObjective To quantify patterns of emergency department (ED) use over two consecutive 12-month periods among children aged 15 and under, and to assess heterogeneity of reasons for attendance in high-frequency users.Design Population-based retrospective cohort study of routinely collected ED data.Setting EDs in the Yorkshire and Humber region, UK, from 31 March 2014 to 1 April 2017.Patients Children aged 15 and under with ≥1 ED attendance.Main outcome measures Proportion with ≥7 attendances over 2 years and heterogeneity of diagnostic reasons quantified by the Herfindahl index.Results The cohort included 71 143 individuals. Although only 13.6% were high-frequency attenders in the first year, over half (55.1%) of these made at least one attendance in the second year. A subset (14.1%) remained high-frequency attenders across both years and were more likely to belong to the most deprived deprivation category. Children aged 8–12 were more likely to attend for injury-related issues and showed lower heterogeneity in reasons for attendance, while infants under age 1 had more illness-related attendances and greater heterogeneity.Conclusions A notable proportion of children and young people frequently attend EDs over a 2-year period. This study introduces a method for quantifying heterogeneity in reasons for attendance, which may support future predictive modelling using electronic health records to identify and support high-frequency ED users
Usable authentication: Are we there yet?
No full textWith technology increasingly embedded in everyday life, the demand for secure and usable authentication methods has never been greater. Traditional password-based systems continue to dominate, despite well-known usability and security challenges. This paper explores the evolution of user authentication technologies, from secret knowledge and tokens to biometrics and emerging approaches such as Passkeys. It critically evaluates the extent to which usability has been achieved, identifying both successes—such as biometrics integrated into smartphones—and persistent issues, including inconsistent guidance, ecosystem dependence, and accessibility barriers. Drawing on academic and commercial developments, the discussion highlights the growing burden on users who must authenticate across multiple devices and services daily. Future directions including transparent, continuous, and user-choice-driven authentication are discussed as potential solutions to mitigate this burden. Ultimately, it argues that while progress has been made, current solutions remain fragmented and often exclude key user groups. A more inclusive, consistent, and user-centred approach is essential to ensure authentication systems are both secure and truly usable in practice
Threat-related mental imagery reduces endogenous pain modulation in healthy individuals
No full textMental imagery-based simulations of threat can evoke “as-if-real” emotional and motivational responses, which may alter top-down pain processing. This study investigated the impact of mental imagery simulations of threat on endogenous pain modulation in n = 71 healthy participants using a cuff-pressure algometry protocol. In block one, participants were assessed on their baseline pain detection threshold (PDT), pressure pain tolerance (PTT), and their conditioned pain modulation (CPM) responses. In the second block, participants underwent the same procedures again but were randomly allocated to imagine the dominant leg cuff as being made of bubble-wrap (benign imagery condition; n = 36) or metal wire (threat imagery condition; n = 35). In between blocks, participants went to a separate room to interact with a piece of real bubble wrap or metal wire around their legs, facilitating mental imagery generation in Block 2. Partially consistent with our hypothesis, mental imagery impacted CPM effects for pain detection threshold (PDT), which was significantly reduced in the Wire relative to the Bubble-wrap condition. Mental imagery did not influence pressure pain tolerance (PPT). These results indicate that mental simulations of threat may reduce threshold-based conditioned pain modulation (CPM) responses in healthy individuals. Present findings suggest that mental simulation of threat may influence endogenous pain modulation processes
Delivering Inclusive Cultural Offers for Social Prescribing: A Realist Evaluation Involving Older People From Global Majority Backgrounds and Cultural Sector Providers in the UK
No full textIntroduction: Research shows cultural activities benefit older people\u27s wellbeing, but little is known about why individuals from global majority (minority ethnic) groups engage less with the mainstream cultural sector, or how it could adapt to meet their needs and encourage engagement. The TOUS study (Tailoring cultural Offers with and for diverse older Users of Social prescribing) investigated the question: What tailoring is needed, how, when and for whom, to optimise cultural offers as part of social prescribing for older people (aged 60+) from global majority groups?. Methods: The TOUS study involved focused ethnographies with six cultural-sector organisations throughout the United Kingdom and 11 key informant interviews with cultural providers. A realist approach was adopted, resulting in the development of a programme theory. Results: The programme theory has three pillars: (1) broker, hook, and opportunity, which support entry into cultural spaces to provide immediate benefits; (2) safety and trust, power-sharing, and meaning, which sustain engagement; and (3) transformative outcomes, including lasting relationships, confidence, and exploring identities. Conclusions: With intentional engagement and relational practices, organisations can foster inclusive cultural participation and support well-being in later life. Patient or Public Contribution: The TOUS study was guided by a public involvement group of six contributors (aged 60+ from global majority/minority ethnic backgrounds) who shared experiences of creative practice, and advised on data collection, analysis, model development, and dissemination. The study also involved collaborative analysis of data at case sites
Presence and characteristics of plastics and microplastics on the seabed of the western English Channel
Get PDFLittle is known about the presence, distribution, origins and characteristics of plastic litter and microplastics on the ocean floor. In this study, plastics trawled from the bed of the western English Channel have been categorised and analysed by a variety of optical and spectroscopic techniques. A total of 90 plastic samples were classified, in descending order of abundance, as food-drink packaging, unknown, homeware, military and fishing. Most samples showed varying degrees of weathering (e.g., discolouration, distortion, cracking, fragmentation) and were visibly fouled by calcareous deposits. The majority of samples were constructed of polymers of negative buoyancy (e.g., polyamides, polyethylene terephthalate and polyvinyl chloride) with one sample identified as positively buoyant (polyethylene). Additives and pigments among the samples included asbestos, glass fibres, Cd-, Pb- and Sn-based stabilisers, Ba- and Ti-based compounds, and antifouling residues. Microscopy revealed the ubiquity of microfibres that were often strongly adhered to the plastic or fouled surfaces and whose polymeric compositions did not match those of the host material. This observation is attributed to encounters of microfibres with a slimy, accruing biofilm on the plastic and suggests that synthetic fibres are highly abundant and persistent in suspension close to the seafloor. The impacts of these fibres are unknown and warrant further investigation