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Instance-Based Transfer Learning with Similarity-Aware Subject Selection for Cross-Subject SSVEP-Based BCIs
Get PDFSteady-state visual evoked potential (SSVEP)-based brain-computer interfaces (BCIs) can achieve high recognition accuracy with sufficient training data. Transfer learning presents a promising solution to alleviate data requirements for the target subject by leveraging data from source subjects; however, effectively addressing individual variability among both target and source subjects remains a challenge. This paper proposes a novel transfer learning framework, termed instance-based task-related component analysis (iTRCA), which leverages knowledge from source subjects while considering their individual contributions. iTRCA extracts two types of features: (1) the subject-general feature, capturing shared information between source and target subjects in a common latent space, and (2) the subject-specific feature, preserving the unique characteristics of the target subject. To mitigate negative transfer, we further design an enhanced framework, subject selection-based iTRCA (SS-iTRCA), which integrates a similarity-based subject selection strategy to identify appropriate source subjects for transfer based on their task-related components (TRCs). Comparative evaluations on the Benchmark, BETA, and a self-collected dataset demonstrate the effectiveness of the proposed iTRCA and SS-iTRCA frameworks. This study provides a potential solution for developing high-performance SSVEP-based BCIs with reduced target subject data
Ecology not genetic covariance explains correlated trait divergence during speciation
Get PDFThe formation of new species often involves the correlated divergence of multiple traits and genetic regions. However, the mechanisms by which such trait covariation builds up remain poorly understood. In this context, we consider two non-exclusive hypotheses. First, genetic covariance between traits can cause divergent selection on one trait to promote population divergence in correlated traits (a genetic covariation hypothesis). Second, correlated environmental pressures can generate selection on multiple traits, facilitating the evolution of trait complexes (an environmental covariation hypothesis). Here, we test these hypotheses using cryptic colouration (controlled by a likely incipient supergene) and chemical traits (i.e., cuticular hydrocarbons, CHCs) involved in desiccation resistance and mate choice in Timema cristinae stick insects. We first demonstrate that population divergence in colour-pattern is correlated with divergence in some (but not all) CHC traits. We show that correlated population divergence is unlikely to be explained by genetic covariation, as our analyses using genotyping-by-sequencing data reveal weak within-population genetic covariance between colour-pattern and CHC traits. In contrast, we find that correlated geographic variation in climate and host plant likely generates selection jointly on colour-pattern and some CHC traits. This supports the environmental covariation hypothesis, likely via the effects of two correlated environmental axes selecting on different traits. Finally, we provide evidence that misalignment between natural and sexual selection also contributes to patterns of correlated trait divergence. Our results shed light on transitions between phases of speciation by showing that environmental factors can promote population divergence in trait complexes, even without strong genetic covariance
WS12.02Dietary protein intake and overall diet quality in adults with cystic fibrosis following elexacaftor/tezacaftor/ivacaftor therapy
No full textDegradable diblock copolymer vesicles via radical ring-opening polymerization-induced self-assembly in aqueous media
No full textThe development of degradable polymeric vesicles is essential for next-generation controlled delivery systems and responsive materials, particularly for therapy and diagnostics. However, achieving precise control over their synthesis and degradation behavior remains a significant challenge. Herein we report the synthesis of degradable diblock copolymer vesicles via radical ring-opening polymerization-induced self-assembly (rROPISA) in aqueous media. This approach employs radical ring-opening copolymerization (rROP) of a thionolactone with a water-miscible vinyl monomer to introduce cleavable thioester groups within the membrane-forming polymer chains. More specifically, a water-soluble poly(N,N-dimethylacrylamide) (PDMAC) precursor is chain-extended by statistically copolymerizing dibenzo[c,e]oxepane-5-thione (DOT) with 2-methoxyethyl acrylate (MEA) using a reversible addition–fragmentation chain transfer (RAFT) aqueous dispersion polymerization formulation. The disparity in reactivity between DOT and MEA is addressed using a comonomer-starved feed strategy, with MEA acting as a cosolvent for the water-insoluble DOT. This controlled feeding approach ensures a more uniform distribution of DOT repeat units within the hydrophobic core block, significantly improves copolymer composition control, enables DOT incorporation of up to ∼4 mol %, and enhances overall comonomer conversion. Compared to conventional one-shot batch syntheses, this strategy yielded vesicles with superior degradation profiles. Morphological characterization using cryogenic transmission electron microscopy (cryo-TEM), dynamic light scattering (DLS) and small-angle X-ray scattering (SAXS) confirmed the formation of well-defined vesicles. Hydrolytic degradation studies conducted in mildly basic aqueous media led to vesicle disintegration, as indicated by cryo-TEM, DLS, and SAXS analyses. Importantly, size exclusion chromatography (SEC) analysis revealed the formation of significantly shorter copolymer chains and final molecular weight distributions comparable to that of the nondegradable PDMAC precursor, indicating efficient hydrolytic degradation of the membrane-forming P(MEA-stat-DOT) block. This study provides valuable insights regarding the rational design of degradable vinyl-based diblock copolymer vesicles, which augurs well for potential biomedical applications
Increasing tree size across Amazonia
Get PDFClimate change and increasing availability of resources such as carbon dioxide are modifying forest functioning worldwide, but the effects of these changes on forest structure are unclear. As additional resources become available, for example, through CO2 fertilization or nitrogen deposition, large trees, with greater access to light, may be expected to gain further advantages. Conversely, smaller light-suppressed trees might benefit more if their light compensation point changes, while bigger trees may be the most negatively impacted by increasing heat and drought. We assessed recent changes in the structure of Earth’s largest tropical forest by analysing 30 years of Amazonian tree records across 188 mature forest plots. We find that, at a stand level, trees have become larger over time, with mean tree basal area increasing by 3.3% per decade (95% CI 2.4; 4.1). Larger trees have increased in both number and size, yet we observed similar rates of relative size gain in large and small trees. This evidence is consistent with a resource-driven boost for larger trees but also a reduction in suppression among smaller trees. These results, especially the persistence and consistency of tree size increases across Amazonian forest plots, communities and regions, indicate that any negative impacts of climate change on forests and large trees here have so far been mitigated by the positive effects of increased resources
Investigating the effect of railway track ballast and bed conditions on the lateral resistance of timber, concrete, steel, and composite sleepers using a novel test methodology
No full textThis study investigates the effect of sleeper (tie) type, ballast condition, and vertical rail restraint forces on sleeper-ballast interaction, which is responsible for lateral resistance behaviour, to support track safety management. Lateral resistance, principally dictated by the sleeper-ballast interaction is a property of ballasted railway track critical to overall track stability, and to the reduction of track buckling risk. Previous investigations of this property have overlooked the restraining effect of the rail which limits the uplift of sleepers during sleeper push tests. A novel single sleeper push tests (SSPT) methodology, utilising a kinematic restraint, has been used to test the lateral resistance of five sleeper types including timber, concrete, steel, and composite. The tests were performed for a range of ballast dimensions and consolidations, with lateral resistance values up to 40 mm displacements presented. The percentage contribution of the sleeper base is calculated for each sleeper, finding reasonable agreement with values found in existing literature. This study has found that for small displacements, concrete and steel sleepers generate similar levels of lateral resistance, with steel sleepers exhibiting increased resistance for extended push distances. Steel sleepers have a concave structure and are found to generate much of their lateral resistance through internal ballast interaction, making them suitable for use in circumstances where the cribs or shoulders are damaged or reduced. Timber and composite sleepers were found to provide lower resistances, approximately 50 % of the peak resistance of concrete sleepers. As railways worldwide are re-engineered to avoid climate change driven infrastructure failures these findings contribute to track safety management by improving buckling mitigation strategies, whilst aiding the selection of more suitable and effective components to alleviate the effects of climate change on the railway track system
An analysis of predictors of conventional and complementary healthcare use in Yorkshire
Get PDFBackground
Well-recognised trends in types of services used by patients exist within
health service utilisation. One increasing area is complementary and alternative
medicine (CAM); considered distinct from the use of health professionals working in
conventional medicine. Little is known about the contribution of CAM and whether
people using CAM with multiple comorbidities make correspondingly less use of
conventional health services. Aims 1) To describe self-reported visits to conventional
health professionals and CAM practitioners, and to identify predictors of such visits; 2)
To quantify the effect of demographic, health-related and CAM service take-up factors
on contact with health services delivered by conventional health professionals.
Methods
Data from 70,836 participants in the Yorkshire Health Study, a large-scale
population-based cohort study, was analysed descriptively and inferentially to test for
associations between variables.
Results
3.5% of the cohort reported accessing CAM
services in the previous three months. Level of contact with conventional health
professionals was higher in those accessing practitioner-led CAM services (incidence
rate ratio [IRR]=1.28; p<0.001.) Female gender, older age and increased incidence of
mental and physical health conditions were also positively associated with the
outcome.
Conclusions
Self-reported utilisation of CAM services was low but there were
several predictors of recent CAM use based on demographic and health conditions
which may be of help in understanding conventional and CAM healthcare utilisation
Advancing net zero carbon construction: A techno-economic and environmental analysis of onsite microgrids and prosumer energy adoption
Get PDFTraditionally reliant on fossil fuels, the construction industry faces increasing pressure to adopt sustainable energy solutions to reduce carbon emissions and achieve Net Zero Carbon Construction (NZCC). This study examines the potential for integrating grid-connected microgrids into construction projects, leveraging renewable energy sources such as solar and wind, combined with energy storage systems, as a pathway to transform construction sites into energy prosumers – entities that produce and consume green energy. A systematic review and meta-analysis were conducted to comprehensively analyse the technical, economic, and environmental dimensions of commonly used microgrid configurations across sectors. The findings demonstrate that microgrids can reduce carbon emissions by up to 80 % compared to traditional grid-based systems, showcasing their superior environmental performance. The hybrid Grid-Connected Photovoltaic-Wind Turbine (G-PV-WT) configuration achieves up to 91 % emission savings, offering 50 % lower costs and payback periods compared to other alternatives. The study recommends site-specific configurations with G-PV-WT systems for construction sites with abundant wind and solar resources. However, it emphasises the need for a multi-criteria decision-making approach that balances technical, economic, environmental, and policy factors to select optimal microgrid solutions for construction sites. A prosumer energy adoption framework is proposed, positioning construction sites as active producers and consumers of green energy, supporting NZCC goals, driving innovation, and promoting sustainable construction practices
Referral experiences of healthcare consumers: results from a cross-sectional study in urban slums in Southeast Nigeria
Get PDFIntroduction: The inadequate referral system in Nigeria is partly due to the proliferation of informal healthcare providers (IHPs) and constraints within formal providers in urban slums. With limited data on patient referral experiences across these providers, this paper explores referral experiences in urban slums in southeast Nigeria.
Methods: This study involved 1,025 people in eight slums in Enugu and Anambra states, using multi-stage purposive sampling. Data on referral experiences were collected through a pre-tested questionnaire and analyzed using descriptive statistics and logistic regression. Ethical approval was obtained, and informed consent was secured.
Results: It found that only 7.4% of patients received referrals from their primary healthcare sources, mostly from patent medicine vendors, private clinics, and primary healthcare (PHC) centres to private clinics and laboratories. Verbal referrals were the dominant modality, although the types of referrals varied significantly between facilities that initiated referrals and between states.
Conclusion: This paper highlights the need for innovative solutions to integrate informal healthcare providers into the formal system, improving referrals and enhancing health services in urban slums
More than a mental health issue:broadening the concept of ‘work capability’ through qualitative secondary analysis of claimant narratives
Get PDFThis article offers a perspective on the policy problem of rising mental-health-related economic inactivity and associated health and disability benefits claims in the UK. Rather than engage directly in debates about whether these health problems are ‘real’, or if and how health assessments should be reformed, we ask a more fundamental question about the way the problem of economic inactivity is being represented in policy. Drawing on Bacchi’s ‘what’s the problem represented to be?’ approach, we consider whether the important but increasingly dominant focus on mental ill health as the cause of inactivity is obscuring understanding of the broader set of factors that simultaneously constrain people’s capacity for work. Through secondary analysis of a large qualitative longitudinal dataset, we illustrate how a multiplicity of structural, economic, social and relational factors shape and constrain people’s capacity for work. Participants gave rich, nuanced and complex accounts of their capacity for work, which revealed that mental distress is just one dimension. However, placed within a welfare system that takes a narrowly medicalised approach to assessing work capacity, coupled with a punitive regime of conditionality and sanctions for those not meeting this criteria, people’s difficulties retaining and regaining work were not comprehensively acknowledged, and mental distress inevitably became the primary lens through which their difficulties were bureaucratically legitimised and responded to. Throughout the analysis, we emphasise that people’s distress is real, genuine and often severe, but it is rarely the whole story of what is blocking their pathway to fulfilling, sustainable employment
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