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3D Reconstruction of DART Ejecta at Dimorphos Reveals an Anisotropic, Filamentary Structure
No full textAbstract
We present a 3D reconstruction of the ejecta plume generated by the DART impact on Dimorphos based on LUKE images acquired by LICIACube. Using adaptive histogram equalization and geometric coregistration from multiple vantage points, we identified and tracked extended ejecta features and reconstructed their 3D spatial distribution with a voxel-based method. The reconstructed ejecta field shows strong anisotropy. An azimuth-matched comparison with the published elliptical cone highlights coherent, direction-dependent departures from a simple conic surface, despite broad agreement on the global cone orientation. This quantifies nonaxisymmetric structures that cone models cannot capture. We derived lower limits to ejecta velocities ranging from 20 to 50 m s
−1
, consistent with numerical simulations of hypervelocity impacts into weak, porous targets. Compared to laboratory experiments, these values correspond to few-meter launch depths, suggesting a significant role of near-surface boulders in the ejecta distribution. Complementing this ejecta filament analysis, we studied 105 isolated comoving diffuse ejecta features, tracked up to 7 km from the impact site. These features followed highly tangential (85
∘
–92
∘
from the impact direction) trajectories relative to Dimorphos’s surface. Their velocity distribution peaks around 50 m s
−1
, indicating that crater excavation persisted throughout the imaging sequence. Our results challenge and refine previous cone-based ejecta distribution models, offering new insights into the complex nature of impact-induced ejecta and improving constraints relevant for planetary defense strategies. Given these new insights, we urge the designers of future planetary defense missions to take into consideration anisotropic ejecta models for more realistic estimates of the imparted momentum via a kinetic impactor technique.
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Strategies to support safe wandering in care homes for older adults - what works, for whom, and in which circumstances?: A realist synthesis.
No full textOBJECTIVES: Wandering is a common behaviour among people with dementia living in care homes, driven by various factors such as enjoyment, a sense of purpose, lifelong habits, and social interaction. These elements can bring both physical and mental benefits, highlighting the need for strategies that enable safe wandering while respecting individual autonomy. This realist synthesis aimed to explore these strategies and the conditions under which they lead to successful outcomes. METHODS: This realist synthesis involved scoping the literature to develop initial theoretical explanations for how different strategies could support safe wandering. From this literature, we developed context-mechanism-outcome configurations, which we combined into initial programme theories. Systematic searches were then used to test and refine these programme theories. Studies were prioritised for inclusion based on criteria of relevance and richness. We extracted data pertinent to the initial programme theories and documented relevance, richness, and rigour. We synthesised data into five refined programme theories. At each stage of the process, we collaborated with stakeholders to develop and validate the strategies. RESULTS: The review included 79 evidence sources, leading to five refined programme theories. 1) Personalised Care: Emphasising the importance of staff practicing person-centred care by understanding residents, their reasons for wandering, and their life histories. 2) Monitoring: Effective monitoring requires good visual access or technological solutions that enable staff to observe residents, and detect when residents need support to walk while also enabling resident freedom and independence. 3) Navigation: Navigation is facilitated by dementia-friendly design features and environmental cues, which help minimise the challenges residents face due to diminished orientation and wayfinding abilities. 4) Managing access: Involving balancing residents' safety and autonomy. Strategies may include restricting access to unsafe areas by locking doors or using technology and camouflage, while ensuring access to safe spaces. 5) Hydration and nutrition: Hydration and nutrition (e.g., suitable snacks) is provided to prevent weight loss for residents who wander and may not stay seated during meals. These theories provide insight into supporting safe wandering, leading to improved wellbeing for both residents and staff, enhanced safety and autonomy for residents, and reduced staff anxiety. DISCUSSION: Strategies that create a supportive environment, provide physical assistance, and support hydration and nutrition enabled residents to wander safely. Identified strategies improved wellbeing for both residents and staff. However, the same strategies also led to ethical concerns around digital monitoring, deception, and access restrictions. STUDY REGISTRATION: The protocol was registered with PROSPERO (CRD42024559085)
Photovoltaic Knowledge-Informed Neural Network (PKINN): Interpretable power prediction model under Fluctuating Environmental Conditions
Full text linkFluctuating Environmental Conditions (FECs) are a critical barrier to accurate photovoltaic (PV) power forecasting. Existing models often fail to capture abrupt and stochastic fluctuations, leading to reduced forecasting reliability. To address this challenge, this study proposes an interpretable Photovoltaic Knowledge-Informed Neural Network (PKINN). The framework incorporates a Quadratic Explicit Model (QEM) to derive explicit expressions of PV power and transparently capture abrupt variations, while a Fluctuation Allocation Mechanism (FAM) employs a fluctuation sensitivity coefficient to quantify fluctuation intensity and allocate input data to specialized prediction branches. The proposed PKINN framework enables adaptive learning across diverse FECs and enhances forecasting performance. Experimental evaluations on two types of PV modules demonstrate that PKINN reduces the root mean square error by at least 8.73% compared with state-of-the-art models across diverse FECs
Racialised deservingness and peripheral whiteness: the case of Albanian asylum seekers in Britain
No full textThis article explores the racialisation of deservingness as experienced by Albanian asylum seekers in Britain. It uses the concept of peripheral whiteness to analyse how their deservingness is constructed and the tactics they use to appear deserving. Drawing on narrative interviews with 44 Albanian asylum seekers aged 16–25 during 2021–2023, the findings show that they interpret their deservingness as structured by two mechanisms of safety and suspicion within their asylum encounters. These operate along racial logics whereby their racialisation positions them as too white and European to be considered unsafe, yet peripheral white and therefore too suspect to be genuine. In response, they adjust their deservingness through restraint, politeness and individuation of risk, and some use the interview space to rework country-level assumptions of safety whilst being attentive to procedural repercussions. The article contributes by showing how peripheral whiteness operates as an evaluative heuristic within asylum governance and by specifying how a moral economy of asylum is reproduced from below through applicants’ deservingness work and tactical self-representation
Politicising safety and racialised and gendered criminalisation: Political agenda-setting and the case of Albanian asylum-seekers in the UK
Full text linkHow the UK government has politicised asylum by categorising Albanian asylum-seekers as ‘criminals’ and Albania as a ‘safe’ country to advance an immigration deterrence agenda remains unresearched. We use agenda-setting and policy framing analytical insights to explain how and why UK government’s successful agenda-setting was underpinned by the racialised and gendered criminalisation of Albanian males and the politicisation of the safety conditions in Albania. Our findings draw on qualitative empirical data, alongside triangulation with official and stakeholder data and documents. We argue that the racialised and gendered criminalisation of Albanian males – as evidenced by political rhetoric and the media – was integral to the targeted legal and political measures making Albania a ‘safe’ country. Nonetheless, we show that these framings misrepresent the reality in Albania and the challenges that vulnerable Albanians face when seeking protection in the United Kingdom.</jats:p
Factors impacting the complexity of the leporid intracranial joint
No full textLeporid lagomorphs, the rabbits and hares, exhibit unique cranial traits that distinguish them from their closest relatives, the Ochotonidae (pikas), and all other mammals. Among these features, the intracranial joint stands out as the only example of cranial kinesis in mammals and is hypothesised to dissipate kinetic energy during high-speed locomotion. Despite its potential functional importance, the morphology of the joint remains understudied. High complexity in other cranial sutures has been associated with behavioural traits such as feeding and head butting. In this study, we quantified the complexity of the intracranial joint using two independent metrics and explored its relationships with overall cranial shape, locomotor mode, cranial size and body mass, burrowing habit, and facial tilt angle. We found significant correlations between complexity and locomotor mode as well as with facial tilt angle, indicating that cursorial species have less complex sutures and highlighting a potential link between the complexity of suture interdigitation and facial tilting. However, complexity did not correlate with size or burrowing habit. Our findings shed more light on the functional anatomy of the leporid cranium and emphasise the need for further research on ontogenetic development, biomechanics, and behaviour to fully understand the evolutionary and functional significance of these unique cranial traits
Nanoscale surface morphology modifications for next-generation supercritical CO2 heat exchangers: Review and perspective
No full textCarbon nanotube (CNT) pin fin arrays, CNT, or nanoparticle coating have emerged in recent decades as novel techniques for enhancing heat transfer and reducing drag. In this paper, the suitability of these techniques is reviewed specifically for heat transfer enhancement and drag reduction in the gas side of supercritical carbon dioxide (SCO2) counterflow tube-in-tube or plate type heat exchangers for applications in CO2 refrigeration systems. The methodology and the applicability of various approaches for predicting the heat transfer rates and the frictional pressure drop associated with flow over a nanocoated surface have been reviewed. Findings from both experimental and numerical studies highlight critical limitations, including a lack of fundamental knowledge about flow over superhydrophobic surfaces and the absence of experimental data for crucial parameters such as temperature jump at the wall, velocity and temperature shifts, and the Reynolds analogy factor for nanotube or nanoparticle coatings in turbulent flow regimes. These limitations significantly hamper the predictive capabilities of both single-scale and multi-scale models for frictional pressure drops and heat transfer coefficients. To enhance the accuracy of these models, it is essential to consider surface parameters such as arithmetic mean roughness (Ra), root-mean-square roughness (Rq), effective slope (Es), skewness (Sk), and kurtosis (ku)
Foreign exchange intervention and financial stability
No full textThe effects of sterilized intervention are studied in a model with financial frictions. The central bank operates a managed float and issues sterilization bonds. In contrast with most of the existing literature, these bonds are held only by banks, and are imperfect substitutes for loans. The model is parameterized and used to study optimal policy responses to capital inflows associated with a transitory shock to world interest rates. The results show that sterilized intervention can be expansionary due to a bank portfolio channel and may exacerbate risks to financial stability. Full sterilization is optimal only when that channel is absent. The optimal degree of intervention is more aggressive when the central bank can choose simultaneously the degree of sterilization; in that sense, and conditional on intervention taking place, the instruments are complements. When the central bank's objective function also accounts for the implicit cost of sterilization, and concerns with that cost are sufficiently high, intervention and sterilization can be substitutes—independently of whether exchange rate and financial stability considerations also matter for policymakers
Diagnostic accuracy of the WHO clinical staging system for detection of immunologically defined advanced HIV disease: A systematic review and meta-analysis
Full text linkIntroduction: People with advanced HIV disease face high risks of severe illness and death. CD4 testing enables timely diagnosis and appropriate care, yet access remains limited in many settings. This review investigated the diagnostic accuracy of the WHO clinical staging for identifying advanced HIV disease. Methods: We conducted a systematic review and meta-analysis of studies published between 1 January 1998 and 1 May 2024 that assessed both WHO clinical staging and CD4 counts in people living with HIV aged 5 years and older (PROSPERO: CRD42024558372). We pooled sensitivity and specificity estimates of WHO Stage 3/4 for detecting advanced HIV disease (CD4 <200 cells/μL) using bivariate random-effects meta-analysis. Risk of bias was assessed using QUADAS-2, and certainty of evidence was appraised using Grading of Recommendations, Assessment, Development, and Evaluations (GRADE). Results: Of 15,194 studies screened, 335 relevant studies were identified, from which 25 were included in evidence synthesis and 21 in the meta-analysis. Most studies were from the WHO African (19/25) and South-East Asian (5/25) regions. Risk of bias was moderate to high in 88% of studies, primarily due to issues with clinical staging assessment. Pooled sensitivity and specificity of WHO Stage 3/4 were 60.7% (95% CI: 48.0%–72.1%) and 72.4% (95% CI: 61.4%–81.3%), respectively. Specificity was significantly higher outside the African region (p < 0.001). In a population of 100,000 people living with HIV with 30% advanced HIV disease prevalence, WHO staging would miss 11,700 true advanced HIV disease cases and misclassify 19,600. Conclusions: WHO clinical staging alone shows low accuracy for detecting advanced HIV disease, risking both missed diagnoses and overtreatment. CD4 testing remains essential for accurately identifying and managing advanced HIV disease
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