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Cognitive modelling of visual attention captures trust dynamics in human-robot collaboration
No full textUnderstanding how humans perceive and interact with robots is crucial for collaborative scenarios. Trust, a pivotal factor in such interactions, is inherently volatile and subjective, posing significant challenges for robots. However, trust has also been shown to influence specific human bio-signals and behaviours, suggesting that it could be inferred from those indicators. One such indicator is visual attention, the cognitive process of focusing on distinct environmental elements, often manifested through eye gaze. Despite recent research connecting eye gaze and trust in Human-Robot Collaboration scenarios, this relationship remains largely unexplored. This paper presents a novel signal, the Attention Arbitration Ratio (AAR), which is shown to be a promising real-time predictor of subjective and objective trust measures. We obtain this signal using a visual attention modelling framework that explicitly emulates the Bottom-Up and Top-Down processes, two key cognitive components. We demonstrate the connection between the AAR and trust using Bayesian data analysis, and we analyse the sensitivity of that connection with different visual attention models. For evaluation purposes, we collected gaze data and trust questionnaires from 49 interactions where 29 participants engaged in a collaborative assistive cooking task with a robot, for a total duration of 24h53 of data collection
On the pseudoelastic-viscoelastic behavior of starch hydrogels at various degrees of gelatinization and retrogradation
No full textStarch, a naturally abundant and widely consumed energy source, is biocompatible and extensively used in the food and pharmaceutical industries. Digestion of starch involves both the mechanical breakdown through mastication and peristaltic waves of the gastrointestinal wall as well as chemical breakdown through diffusion and reaction with saliva and gastrointestinal fluids. The mechanical properties of starch hydrogels significantly influence their breakdown and digestion speed, making it essential to investigate these properties. However, the effects of the degree of gelatinization (DOG) and degree of retrogradation (DOR) on the loading-unloading mechanical properties, which are essential for material model development and in silico digestion simulations, remain inadequately investigated. This study performed mechanical experiments to investigate the mechanical properties of starch hydrogels across different degrees of gelatinization and retrogradation, influenced by heating and storage conditions. Gelatinization was observed under optical microscopy by noting the loss of the spherical shape of the starch granules. The degree of retrogradation was measured using Differential Scanning Calorimetry (DSC). Starch hydrogels exhibit stress-softening behavior and viscoelasticity, varying with different degrees of gelatinization and retrogradation due to the crystallite melting and the recrystallization of the starch molecules. A pseudoelastic-viscoelastic constitutive law was developed to describe the mechanical behavior of the starch hydrogel, and the material parameters were calibrated based on experimental results. Such models are required for the simulation of the digestion of starch hydrogels. This study assists in understanding the influence of cooking and storage conditions on the mechanical behavior of starch hydrogels
Diffusion-mediated adsorption versus absorption at partially reactive targets: a renewal approach
No full textRenewal theory is finding increasing applications in non-equilibrium statistical physics. One example relates the probability density and survival probability of a Brownian particle or an active run-and-tumble particle with stochastic resetting to the corresponding quantities without resetting. A second example is so-called snapping out Brownian motion, which sews together diffusions on either side of an impermeable interface to obtain the corresponding stochastic dynamics across a semi-permeable interface. A third example relates diffusion-mediated surface adsorption–desorption (reversible adsorption) to the case of irreversible adsorption. In this paper we apply renewal theory to diffusion-mediated adsorption processes in which an adsorbed particle may be permanently removed (absorbed) prior to desorption. We construct a pair of renewal equations that relate the probability density and first passage time (FPT) density for absorption to the corresponding quantities for irreversible adsorption. We first consider the example of diffusion in a finite interval with a partially reactive target at one end. We use the renewal equations together with an encounter-based formalism to explore the effects of non-Markovian adsorption/desorption on the moments and long-time behaviour of the FPT density for absorption. We then analyse the corresponding renewal equations for a partially reactive semi-infinite trap and show how the solutions can be expressed in terms of a Neumann series expansion. Finally, we construct higher-dimensional versions of the renewal equations and derive general expression for the FPT density using spectral decompositions
Exploring the effects of wearing facemasks on stair safety characteristics in young adults
No full textIntroduction
Facemasks are worn in many industries to protect from infections and harmful substances. Asian countries historically have a wide adoption of facemasks; though due to the COVID-19 pandemic, facemask wearing is also common in western countries. The lower visual field provides important information for safe stair negotiation. A loose fit facemask may obstruct the lower visual field and negatively affect stair negotiation. Pinching a facemask nose clip provides contour around the nose which may reduce lower visual occlusion and negative stair behaviour effects. Here, we explored the effect of wearing a Type IIR facemask and nose clip pinch adjustment on lower visual field occlusion and stair walking behaviour
Method
Eight young adults ascended and descended stairs with; 1) no facemask, 2) unadjusted facemask, 3) customised facemask (nose clip pinched). Measurements included peak head flexion, lower visual field occlusion, stair duration, foot clearance, foot placement, margins of stability, Conscious Movement Processing and anxiety.
Results
Unadjusted increased lower visual occlusion during descent (unadjusted = 32° ± 14° vs no facemask = 11° ± 14°, p < 0.001), (unadjusted vs customised = 21° ± 15°, p = 0.009) and ascent (unadjusted = 47° ± 12° vs no facemask = 25° ± 11°, p < 0.001), (unadjusted vs customised = 35° ± 11°, p = 0.005). Unadjusted increased conscious movement processing during descent (unadjusted = 16 ± 5 vs no face mask 11 ± 4, p = 0.040) and ascent (unadjusted = 16 ± 5 vs no face mask = 10 ± 3, p = 0.044). Bayesian inference indicated moderate evidence for the alternative hypothesis for descent duration, peak head flexion and anxiety. Anecdotal and strong evidence for the alternative hypothesis were found for ascent duration and anxiety respectively. No differences were found in foot kinematics or margins of stability.
Discussion
Simple adjustments (pinching the nose clip) to a Type IIR facemask have the benefit of reducing the lower visual field occlusion an unadjusted mask creates, and helps improve stair safety characteristics in young adults
What are the greatest opportunities for innovation to improve access to and quality of palliative care services to children? A qualitative interview study
No full textBackground
Innovation is required within children’s palliative care (CPC) to improve access to and quality of care. Existing research demonstrates a lack of access to CPC worldwide. This study aimed to explore the current opportunities for innovation within CPC from the provider’s perspective.
Methods
Global leaders in CPC were purposively sampled and invited to partake in a qualitative semi-structured interview. Data were thematically analysed using an inductive approach.
Results
Fifty-one CPC leaders from 27 countries were interviewed, encompassing clinical, managerial and patient advocacy roles. A thematic framework housing nine key themes was created, reflecting what innovation means in the context of CPC and the future of innovation. Key findings included opportunities to leverage new technologies within the sector. The importance of a clear vision and user-centred design were seen as crucial when innovating in CPC.
Conclusions
This study provides novel insights into opportunities for innovation in CPC, creating a thematic framework that brings together key themes and may help guide future innovation. We also highlight essential areas for innovation such as the use of technology. In the context of existing guidance for the delivery of CPC, leaders and policy makers can use the insights from this work to innovate and improve quality and access to CPC worldwide
When maritime meets aviation: the safety of seaplanes on the water
No full textThe water environment is a dynamic domain critical to global transportation and commerce, where seaplanes operate during take-offs, landings, and ground operations, often near maritime traffic. Canada’s vast remote regions and unique geography increase reliance on seaplanes, especially for private and recreational purposes. This article examines the intersection of aviation and maritime operations through a mixed-methods approach, analyzing seaplane safety on waterways using quantitative and qualitative methods. First, data from 1005 General Aviation (GA) seaplane accidents in Canada (1990–2022) are analyzed, revealing 179 fatalities, 401 injuries, and 118 destroyed aircraft—significant given that seaplanes comprise under 5% of GA aircraft. Of these, 50.35% occurred while the seaplane was not airborne. Second, insights from interviews, focus groups, and questionnaires involving 136 participants are explored through thematic and content analysis. These capture pilot concerns that are not evident in accident data, such as hazards from jet ski interactions and disruptive boat wakes. The findings highlight risks like limited visibility and maneuverability during waterborne take-offs, worsened by seaplanes’ lack of priority over maritime vessels in shared spaces. This article concludes with recommendations for both the seaplane and maritime communities, including increasing awareness among boaters about the presence and operations of seaplanes, as well as regulatory adjustments, particularly considering the right of way
Mortality outcomes in lung cancer patients with and without type 2 diabetes: a cohort study in England
No full textIntroduction
The impact of type 2 diabetes (T2DM) on mortality following lung cancer diagnosis remains unclear, with conflicting evidence across studies We aimed to to assess differences in all-cause and cause-specific mortality between lung cancer patients with and without T2DM within a primary care population in England.
Methods
The study population were 69,674 people with incident lung cancer within the Clinical Practice Research Datalink (CPRD) Aurum primary care database (2010-2022). The study exposure was T2DM at cancer diagnosis and the outcomes were all-cause and cause-specific mortality (cancer, cardio-vascular, respiratory). Cox models were fitted for each outcome adjusting for age, gender, smoking status, body mass index, calendar year and socioeconomic status (Index of Multiple Deprivation).
Results
After adjusting for age and gender there was no evidence for a difference in all-cause mortality in people with T2DM compared with people without T2DM (IRR 0.98 95%CI 0.96, 1.01). After additional adjustment for all confounders there was a small positive effect (IRR 1.07 95% CI 1.04, 1.09). After adjusting for age and gender people with T2DM had lower rates of cancer-specific mortality compared to people without T2DM (IRR 0.96 95% CI 0.94, 0.98). However, after adjustment for all measured confounders there was a small positive association (IRR 1.05 95% CI 1.02, 1.07). In both age and gender adjusted and fully adjusted models people with T2DM had higher cardiovascular (fully adjusted HR 1.30 95%CI 1.15, 1.47) and respiratory disease mortality (fully adjusted HR 1.30 95% CI 1.15, 1.47).
Conclusions
There was robust evidence that people with T2DM had higher cardiovascular and respiratory disease mortality following lung cancer diagnosis. The relationships between T2DM and all-cause and cancer-specific mortality were highly sensitive to adjustment for confounding. Differences in studies on approaches to confounding and levels of missing data may contribute to the mixed findings on this association in the literature
Asymptotic scaling laws for periodic turbulent boundary layers and their numerical simulation up to Reθ = 8300
No full textWe provide a rigorous analysis of the self-similar solution of the temporal turbulent boundary layer, recently proposed by Biau (2023), in which a body force is used to maintain a statistically steady turbulent boundary layer with periodic boundary conditions in the streamwise direction. We derive explicit expressions for the forcing amplitudes which can maintain such flows, and identify those which can hold either the displacement
thickness or the momentum thickness equal to unity. This opens the door to the first main result of the paper, which is to prove upper bounds on skin friction for the temporal
turbulent boundary layer. We use the Constantin-Doering-Hopf bounding method to show, rigorously, that the skin friction coefficient for periodic turbulent boundary layer
flows is bounded above by a uniform constant which decreases asymptotically with Reynolds number. This asymptotic behaviour is within a logarithmic correction of well-known empirical scaling laws for skin friction. This gives the first evidence, applicable at asymptotically high Reynolds numbers, to suggest that Biau’s self-similar solution of the temporal turbulent boundary layer exhibits statistical similarities with canonical, spatially evolving, boundary layers. Furthermore, we show how the identified forcing formula implies an alternative, and simpler, numerical implementation of periodic boundary
layer flows. We give a detailed numerical study of this scheme presenting direct numerical simulations up to Reθ = 2000 and implicit large-eddy simulations up to Reθ = 8300, and show that these results compare well with data from canonical spatially evolving boundary layers at equivalent Reynolds numbers
Associations between B vitamin interactions with polyunsaturated fatty acids and cognitive function among cognitively healthy older people as modified by amyloid status and sex
No full text<Background/Objectives: Nutrients such as vitamin B12, folate (B9), and polyunsaturated fatty acids (PUFAs) may independently influence cognitive health, but their combined effects and interactions remain unclear. This study aims to investigate the effects of B12, folate, and PUFAs, including their interactions, on cognitive function in cognitively healthy older adults, considering effect modification by sex and amyloid-beta status. Methods: A cross-sectional analysis was conducted using data from 321 participants aged 60–85 y enrolled in the UK CHARIOT–PRO SubStudy. Dietary intake was assessed using the Scottish Collaborative Group Food Frequency Questionnaire, and cognitive performance was measured via the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Stratified multivariate linear regression models by sex and amyloid-beta status and models with the saturated to unsaturated fatty acid ratio (substituted for PUFAs) as one of the predictors were constructed. Results: Males had lower total RBANS scores with a higher PUFA intake (β = −13.97, p = 0.04) but improved scores with increased folate (β = 9.08, p = 0.04). PUFA × folate revealed contrasting effects to PUFAs alone, with higher cognitive scores in the amyloid-negative group for total RBANS (β = 13.27, 95%: 3.81~22.73, p = 0.01) but lowered scores in the amyloid-positive group. Considering the UFA:SFA ratio, higher delayed memory scores were associated with the combined intake of folate, B12, and PUFAs (β = 7.46, p = 0.02) among females. In the amyloid-positive group, the negative cognitive effects observed with PUFAs were reversed when UFA:SFA was considered. Conclusions: Amyloid status and sex significantly influenced the cognitive effects of nutrient intake, with distinct patterns based on specific cognitive domains and nutrient interactions