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LES validation on near-field wingtip vortex evolution with wind tunnel characterization at low Reynolds number
Get PDFWind tunnel tests are commonly used to visualize the trailing vortices, but tests involving advanced optical measurement techniques can be costly. Camera-based experiments are more affordable, but the low visibility caused by smoke particles and limitations of the upright view make vortex characterization and quantification challenging. In this paper, the proposed perspective upright correction allows adjustment of the slanted plane during post-processing. This technique has reduced the complexity of wind tunnel set-up, and yet yielding a more accurate result than the native upright view. Large Eddy Simulation (LES) is then utilized with proper mesh design within the vortex core volume to effectively capture the smaller scales features of the wingtip vortex and validate against the perspective upright corrected characterization from wind tunnel experiment. The vortex core defined by its maximum tangential velocity will be analyzed against the physical wake evolution captured in wind tunnel, providing insights into the relationship between these two methodologies. The demonstrated accuracy and credibility of the CFD model can ensure that the future simulations in the extended field can be accurately predicted and analyzed
Peak-shaving investigation of a novel flexible two-stage heat pump for heating
Get PDFSince buildings account for a large portion of global energy consumption and greenhouse gas emissions, several nations are expecting to install net-zero emission buildings. The governors have set a carbon–neutral objective for 2050, which requires that all new construction have net-zero emissions. As heat pumps are considered a substitution for gas boilers, in this study, a thermal energy storage system is introduced to a two-stage heat pump system in a novel configuration. The novel flexible two-stage heat pump has been studied and compared with a baseline two-stage heat pump, as well as the same flexible and baseline single-stage heat pump, in the same working conditions. A control strategy has been defined based on the heating duty, hour of the day, and storage tank status to run the system in different modes: 1- Normal operation, 2- Charging, 3- discharging, and 4- stand by modes. The weather data of Glasgow and Birmingham cities, UK have been used to acquire the variable hourly heating loads of a typical 4-story residential block via IESVE software. Also, to study the effect of heating load profile shape, a sinusoidal daily heating load profile has been created with the same maximum duty of variable load from IESVE. The results show that a flexible two-stage system shows 1.67%, and 5.31% higher seasonal COP (seasonal coefficient of performance) with real variable loads, and sinusoidal loads, respectively. While the maximum 2.1% cut price has been shown with sinusoidal loads, the price cut for the real variable loads is less than that
The parasitic nematode Haemonchus contortus lacks molybdenum cofactor synthesis, leading to sulphite sensitivity and lethality in vitro
Get PDFSulphite oxidase has an essential role in detoxifying environmental and endogenously generated sulphite into sulphate and requires the molybdenum cofactor (Moco) to function. Until recently it was believed that the synthesis pathway for Moco was so important for survival that it was conserved in all multicellular animals. Here we report the use of comparative genomics to identify the absence of the first enzyme involved in Moco synthesis in Haemonchus contortus, a highly pathogenic and economically important helminth of livestock that, similar to many parasitic nematode species, has proved difficult to maintain in vitro. We show that Moco deficiency in Haemonchus leads to a high sensitivity to environmental sulphite and limits the ability to maintain the early parasitic larval stages in vitro. Analogous losses in Moco synthesis in other recently sequenced nematode species are also identified. These findings may lead to improved culture methods for parasitic nematodes and to novel approaches for their control
Piloting a minimum data set for older people living in care homes in England: a developmental study
Get PDFBackground:
We developed a prototype minimum data set (MDS) for English care homes, assessing feasibility of extracting data directly from digital care records (DCRs) with linkage to health and social care data.
Methods:
Through stakeholder development workshops, literature reviews, surveys and public consultation, we developed an aspirational MDS. We identified ways to extract this from existing sources, including DCRs and routine health and social care datasets. To address gaps, we added validated measures of delirium, cognitive impairment, functional independence and quality of life to DCR software. Following routine health and social care data linkage to DCRs, we compared variables recorded across multiple data sources, using a hierarchical approach to reduce missingness where appropriate. We reported proportions of missingness, mean and standard deviation (SD) or frequencies (%) for all variables.
Results:
We recruited 996 residents from 45 care homes in three English Integrated Care Systems. 727 residents had data included in the MDS. Additional data were well completed (<35% missingness at wave 1). Competition for staff time, staff attrition and software-related implementation issues contributed to missing DCR data. Following data linkage and combining variables where appropriate, missingness was reduced (≤4% where applicable).
Discussion:
Integration of health and social care is predicated on access to data and interoperability. Despite governance challenges we safely linked care home DCRs to statutory health and social care datasets to create a viable prototype MDS for English care homes. We identified issues around data quality, governance, data plurality and data completion essential to MDS implementation going forward
Modelling and verifying BDI agents under uncertainty
Get PDFBelief-Desire-Intention (BDI) agents feature uncertain beliefs (e.g. sensor noise), probabilistic action outcomes (e.g. attempting and action and failing), and non-deterministic choices (e.g. what plan to execute next). To be safely applied in real-world scenarios we need reason about such agents, for example, we need probabilities of mission success and the strategies used to maximise this. Most agents do not currently consider uncertain beliefs, instead a belief either holds or does not. We show how to use epistemic states to model uncertain beliefs, and define a Markov Decision Process for the semantics of the Conceptual Agent Notation (Can) agent language allowing support for uncertain beliefs, non-deterministic event, plan, and intention selection, and probabilistic action outcomes. The model is executable using an automated tool—CAN-verify—that supports error checking, agent simulation, and exhaustive exploration via an encoding to Bigraphs that produces transition systems for probabilistic model checkers such as PRISM. These model checkers allow reasoning over quantitative properties and strategy synthesis. Using the example of an autonomous submarine and drone surveillance together with scalability experiments, we demonstrate our approach supports uncertain belief modelling, quantitative model checking, and strategy synthesis in practice
Ecosystem-based adaptation strategies to multi-hazard risk reduction and policy implications in the Pearl River and Yangtze River deltas, China
Get PDFThere is growing interest in ecosystem-based adaptation (EbA) as an approach for climate change adaptation, disaster risk reduction (DRR), and the achievement of sustainable development goals. In this study, EbA is synonymous with ecosystem-based DRR for climate-related risk reduction and aligns with nature-based solutions designed for climate change adaptation. Its practice emphasizes the co-benefits of ecosystem protection and restoration, such as reduced exposure to various natural hazards, reduced vulnerability, and enhanced livelihood resilience. Establishing localized EbA initiatives to effectively respond to climate change requires an integrated assessment encompassing the understanding of dynamics of the local social-ecological system. Here, we use two risk assessment frameworks that comprehensively consider social and ecological dimensions of risk. The Global Delta Risk Index (GDRI) addresses social susceptibility, coping and adaptive capacity, ecosystem susceptibility and ecosystem robustness as core components of vulnerability. The DELTA-ES-SES framework, which is derived from the GDRI, additionally considers the intensity of multiple hazards and the importance of ecosystem services in reducing disaster risks. Using both frameworks, we (1) map high disaster risk areas in the Pearl River and Yangtze River deltas, (2) analyse regional differences in vulnerability and risk levels caused by different risk components within deltas, (3) identify key ecosystem services that relate to disaster risk, (4) outline EbA designs applicable to priority regions, and (5) provide policy suggestions for future plans. In doing so, we highlight the linkages between ecosystem services, current EbA practices, and global/national policies to promote the success of EbA in regions exposed to natural hazards
Leveraging Social Robots to Promote Hand Hygiene: A Cross-Cultural and Socio-Economic Study of Children in Diverse School Settings
Get PDFThis study explores the impact of socio-economic and cultural factors on handwashing behaviour in schools through a robot-assisted intervention. We evaluated hand hygiene compliance across three schools, one in India and two in the UK, representing different cultural and socio-economic backgrounds, using the “WallBo” social robot to guide students (n=77) through proper handwashing techniques. The results revealed that students from lower socio-economic backgrounds demonstrated greater initial learning gains, particularly in the Indian school where the novelty of the robot contributed to heightened engagement. However, these gains were not sustained post-intervention, underscoring the importance of continuous reinforcement strategies in under- resourced settings. In contrast, students from higher-income schools demonstrated more consistent retention, likely due to stronger baseline knowledge and greater familiarity with technology. These findings underscore the importance of contextualising technology-driven interventions using social robots within socio-cultural frameworks to maximise long-term impact. Additionally, this study highlights the potential of social robots as an effective educational tool in diverse school environments, provided that long-term reinforcement strategies are put in place
Non-Specific Pleuritis: an update
Get PDFPurpose of Review:
Non-Specific Pleuritis (NSP) is a common diagnosis following thoracoscopy and encompasses a broad range of aetiologies with heterogeneous outcomes. In this article, we review pathophysiology, associated syndromes, and current best practice in follow-up.
Recent Findings:
NSP typically runs a benign disease course; however, the biomechanical consequences of subsequent tissue re-modelling can be severe. A proportion of patients develop malignancy, notably pleural mesothelioma (PM), and clinicians currently lack the ability to stratify those at risk. Some may be harbouring occult malignancy with false-negative pleural biopsies. Alternatively, NSP may represent a true pre-PM precursor supported by the recent characterisation of mesothelioma-in-situ.
Summary:
Prospective surveillance of NSP patients could unlock the final biological milestone preceding PM evolution. Progress in this area would permit a more personalised patient stratification, whilst offering novel opportunities for translational research. The PREDICT-Meso International Accelerator Network has been established to focus on this goal
The 30 m land cover dataset for capturing land cover changes induced by ecological restoration from 1990 to 2022 on the Chinese Loess Plateau
Get PDFContinuous time-series of land cover is critical for attributing runoff, sediment and carbon changes on the Chinese Loess Plateau (CLP). However, current land cover products with annal temporal resolution lack spatial identification accuracy, particularly in capturing authentic changes of cropland, forest and grassland. To address these issues, a 30 m annual land cover dataset was proposed by the Yellow River Conservancy Commission (YRCC_LPLC) for the CLP from 1990 to 2022. Different levels of land cover were classified using different combinations of spectral, monthly and annual temporal and topographic features and Random Forest classifier. Compared to other land cover products (45.64%–73.38%), the accuracy of YRCC_LPLC has a better performance with an overall accuracy of 85.16%. The YRCC_LPLC is capable of capturing not only the explicit spatial variation but also the change direction and change time of land cover, especially for the most critical conversion of cropland into forest and grassland induced by implementation of Grain to Green Program on the CLP
Insights on avian life history and physiological traits in Central Africa: ant-following species have young-dominated age ratios in secondary forest
Get PDFThe Congo Basin rainforest and adjacent Lower Guinea Forest constitute the second largest tract of lowland tropical rainforest in the world. As with the rest of the continent, human population is increasing rapidly and forest degradation is ubiquitous. Forest degradation through logging has pervasive negative effects on ecosystems, but selective logging is considered less impactful than clearcutting. Recent research in Afrotropical forest shows that certain avian species and guilds are more affected by selective logging than others (e.g., specialist insectivores such as followers of Dorylus driver ants); however, the mechanisms behind these patterns are poorly known. In an eight-year mist-netting effort in Equatorial Guinea, we caught 1193 birds in primary forest and high-grade selectively logged forest to determine the effect of disturbance on six demographic and physiological measures on birds. We compared five life history and population traits for ten insectivorous species: proportion of breeding and molting birds, molt-breeding overlap, bird age, and a body mass index. We also analyzed the concentrations of the stress hormone feather corticosterone (fCORT) in five species. All three strict ant-following species (Alethe castanea, Chamaetylas poliocephala, Neocossyphus poensis), and the Muscicapid robin Sheppardia cyornithopsis had a higher proportion of first year birds in secondary forest. Furthermore, two ant-followers, A. castanea and C. poliocephala, had a higher proportion of individuals molting in primary forest. Finally, only Illadopsis cleaveri had higher body condition in secondary forest. We found no differences in breeding status, molt-breeding overlap or fCORT between forest types. Using a long-term mist-netting effort, we use measures taken from birds in-the-hand to go beyond insights from point counts alone; we gain valuable insights into the demography and physiology of Afrotropical birds occupying variably degraded lowland tropical rainforest
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