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Novel feature-based method for multi-modal biomedical image registration compared to intensity-based technique
No full textMultimodal image registration plays a crucial role in biomedical research, enabling the integration of complementary information from different imaging techniques. We present a novel feature-based approach for multimodal image registration, alongside traditional intensity-based methods. Our method, inspired by SPP-net architecture, employs multi-level feature extraction for robust image alignment. Additionally, we perform t-SNE dimensionality reduction on the MALDI-MSI dataset to enhance feature discrimination and visualization. We evaluated both approaches using datasets from the ANHIR Grand Challenge and mass spectrometry imaging modalities (LA-ICP-MS and MALDI-MSI). The proposed feature-based method achieved comparable accuracy to optimized intensity-based approaches, with Dice Coefficients of 0.95 for ANHIR samples (e.g., COAD_05) and 0.97 for mass spectrometry data, while requiring approximately 50% less computational time. Quantitative evaluation through Mutual Information metrics and Hausdorff Distance demonstrated high registration accuracy across different tissue types and imaging modalities. These results establish our feature-based approach as an efficient alternative to traditional intensity-based methods for multimodal image registration in biomedical applications
Plasmonic gold nanostars conjugated poly(heptazine imide) for photocatalytic H2O2 production from O2 reduction
No full textRecent advances in photocatalytic systems for H2O2 production have led to improvements in both efficiency and selectivity; however, the practical application of current photocatalysts remains limited by low H2O2 production rates, poor long-term stability, and challenges in scalability. In this study, we present a novel photocatalyst based on the integration of gold nanostars (AuNSs) into poly(heptazine imide) (PHI) resulting in a system that is highly efficient for H2O2 production. The resulting AuNSs–PHI catalyst achieved a remarkable H2O2 generation rate of 286.95 mM g−1 h−1 under solar irradiation, utilising O2 reduction coupled with isopropanol oxidation. This enhanced performance is primarily attributed to localized surface plasmon resonance (LSPR) effects from the embedded gold nanostars, which significantly boost light absorption and charge separation efficiency. The critical role of the optimized nanostructure was further validated through time-dependent density functional theory (TDDFT) calculations on a gold cluster (Au20) adsorbed onto PHI, providing theoretical insight into the observed experimental H2O2 production enhancement. These findings demonstrate the potential of plasmon-enhanced photocatalysis as a viable pathway for sustainable and scalable H2O2 production
Patterns of online consultation use in Great Britain, 2019 to 2023: an observational analysis
No full textObjective: To examine Online Consultation (OC) uptake and usage patterns over time in Great Britain
by patient characteristics, practice location, and condition/symptom-specific OC template type, for a
major provider of OC services (eConsult).
Methods and Analysis: An observational study was conducted using records of OCs completed
between January 2019 and December 2023. Main outcome measures were OC volume and rates by
country, region, deprivation level, template type, and user demographics (age group and sex).
Results: Over 43 million OCs were submitted on the eConsult platform within the timeframe. The
number of OCs per month greatly increased in early 2020 after the introduction of COVID-19
pandemic restrictions on in-person contacts. Sign-ups to the platform were highest between
February and May of 2020. At their respective peaks, 43.7% of English practices, 11.6% of Scottish
practices, and 50.5% of Welsh practices were active in eConsult. Rates of OCs declined throughout
2022 and most of 2023 and were highest in more affluent areas. For England, Scotland, and Wales,
respectively, OC rates peaked in October 2021 at 17.6, 10.5, and 20.4 OCs per 1000 GP-registered
patients. Nearly two-thirds (64.4%) of OCs were completed by female patients. The proportion of
OCs for children aged ≤10 has risen over time. Eighty-nine percent of OCs were submitted to the
patient’s practice, whereas 7.7% were redirected out towards urgent or emergency care services.
Over time, there have been decreases in the number of OCs submitted at the weekend and in usage
of generic “general advice” templates.
Conclusion: These findings reveal the substantial and evolving utilisation of eConsult over time across
Great Britain. These findings may reflect evolving product functionality and engagement with OC
services by patients and clinical staff, or local differences in service coordination
General practitioners, attention deficit hyperactivity disorder and the risks of stimulant mismanagement
No full textBirds combined calls more than 11 million years ago
No full textMultiple members of the tit and chickadee (= Parid) family combine two classes of calls, F and D, in a rigid order FD. In Japanese tits, FD has been argued on the basis of multiple experiments to involve syntax and non-trivial compositionality. How ancient are these call combinations? We show that FD combinations (as well as individual F and D calls) are present in nearly all Parid species, and almost absent in their closest relatives, the Remizidae and Stenostiridae. Using phylogenetic tools and ancestral reconstruction methods, we infer that FD combinations very likely emerged between 11 and 26 million years ago in the eastern Himalayas. This result contributes to evolutionary animal linguistics using a comparative phylogenetic approach to reconstruct the evolution of call combinations
Identification and characterisation of vaginal bacteria-glycan interactions implicated in reproductive tract health and pregnancy outcomes
No full textLactobacillus displacement from the vaginal microbiome associates with adverse health outcomes and is linked to increased risk of preterm birth. Glycans mediate bacterial adhesion events involved in colonisation and infection. Using customised glycan microarrays, we establish glycan interaction profiles of vaginal bacteria implicated in reproductive health. Glycan binding signatures of the opportunistic pathogens Escherichia coli, Fusobacterium nucleatum and Streptococcus agalactiae to oligomannose N-glycans, galactose-terminating glycans and hyaluronic acid, respectively are highly distinct from Lactobacillus commensals. Binding to sulphated glycosaminoglycans by vaginal bacteria is pH dependent, as is binding to neutral and sialic acid-terminating glycans by F. nucleatum. Adhesion of Lactobacillus crispatus, Lactobacillus iners, Gardnerella vaginalis, S. agalactiae and F. nucleatum to vaginal epithelial cells is partially mediated by chondroitin sulphate. S. agalactiae binding to chondroitin sulphate C oligosaccharides is inhibited by L. crispatus. This study highlights glycans as mediators of vaginal bacterial binding events involved in reproductive health and disease
Temporal multi-omic analysis of COVID-19 in end-stage kidney disease
No full textPatients with end-stage kidney disease (ESKD) are at high risk of severe COVID-19. We performed longitudinal single-cell immune profiling of ESKD patients with COVID-19.
Transcriptome, surface proteome and immunoreceptor sequencing data were generated on 580,040 high-quality cells, derived from 187 samples from 61 patients. For a subset of individuals, we obtained samples before and during infection, allowing intra-individual comparison. Longitudinal profiling demonstrated distinct temporal gene expression trajectories in severe/critical versus mild/moderate COVID-19. We identified a population of
transcriptionally distinct monocytes that emerged in peripheral blood following glucocorticoid treatment. Evaluation of clonal T cell dynamics showed that the fastest expanding clones were enriched in known SARS-CoV-2 specific sequences and shared across multiple patients.
Comparison with external datasets revealed upregulation of immune cell TGB-β pathway expression in ESKD, irrespective of COVID-19 status. Our data delineate the temporal dynamics of the immune response in COVID-19 in a high-risk population
Sensing of extracellular L-Proline availability by the integrated stress response determines the outcome of cell competition
No full textCell competition is a conserved fitness quality control that eliminates cells that are less-fit than
their neighbours. How winner cells induce the elimination of losers is poorly understood. We tackle
this question by studying the onset of differentiation in mice, where cell competition eliminates 35%
of embryonic cells. These loser cells have mitochondrial dysfunction, which we show causes amino
acid deprivation and activation of the integrated stress response (ISR), a pathway essential for
their survival. We demonstrate that L-Proline is a key amino acid sensed by the ISR and that, in a
Proline, that represses the ISR and drives their elimination. These results indicate that cell
competition acts as a novel tissue sparing mechanism, regulated by the availability of extracellular
amino acids, that allows for the elimination of dysfunctional cells when amino acids are plentiful
but ensures their survival in nutrient-poor environments
Enhanced solar water oxidation and unassisted water splitting using graphite-protected bulk heterojunction organic photoactive layers
No full textPolymer donors and non-fullerene acceptors have played an important role as photoactive materials in the development of high-efficiency organic solar cells and have immense potential in devices for direct solar hydrogen generation. However, their use in direct solar water-splitting devices has been limited by their instability in aqueous environment and recombination losses at the interface with catalysts. Here we report anodes containing PM6:D18:L8-BO photoactive layers reaching high solar water oxidation photocurrent density over 25 mA cm−2 at +1.23 V versus reversible hydrogen electrode and days-long operational stability. This was achieved by integrating the organic photoactive layer with a graphite sheet functionalized with earth-abundant NiFeOOH water oxidation catalyst, which provides both water resistance and electrical connection between the catalyst and the photoactive layer without any losses. Using monolithic tandem anodes containing organic PM6:D18:L8-BO and PTQ10:GS-ISO photoactive layers, we achieve a solar-to-hydrogen efficiency of 5%. These results pave the way towards high-efficiency, stable and unassisted solar hydrogen generation by low-cost organic photoactive materials
Identifying gaps in the HIV treatment cascade in Africa: a model comparison study
No full textBackground
Although HIV incidence has considerably decreased in eastern, central, and southern Africa, new HIV infections continue to be a major public health challenge in the region. We aimed to investigate where in the HIV treatment cascade new transmissions are occurring in Malawi, Zimbabwe, and South Africa (the three countries involved in the Modelling to Inform HIV Programmes in Sub-Saharan Africa project).
Methods
In this model comparison study, we used six well described and independently calibrated HIV transmission dynamics models that have been used to inform HIV policy in Africa (Optima HIV, EMOD, Goals, Thembisa, PopART-IBM, and HIV Synthesis) to estimate and predict the proportion of annual new HIV transmissions attributable to people living with HIV who are undiagnosed, have been diagnosed but have not yet started antiretroviral therapy (ART), are receiving ART, and have interrupted ART in Malawi, Zimbabwe, and South Africa from 2010 to 2040 stratified by the age and sex of the individual acquiring HIV.
Findings
Despite the different model structures and underlying assumptions, the six models were well aligned in relation to key HIV epidemic characteristics (including population estimates and HIV prevalence) in each of the three settings. There was, however, considerable variation in the predicted number of new infections, particularly in Malawi and Zimbabwe where this number ranged from fewer than 10 000 new infections to over 30 000 new infections in 2024. Most model results suggested that the mean age of HIV acquisition has been increasing since 2000, with men acquiring HIV at an older age than women in all three settings. All models attributed fewer than 5% of transmissions to individuals who had been diagnosed but had not yet started ART. In Malawi, the proportion of transmissions attributable to undiagnosed people with HIV in 2024 ranged from 33·3% to 75·3% across the models, and transmissions attributable to individuals who had experienced interrupted treatment ranged from 8·4% to 20·1%. In Zimbabwe, the proportion of transmissions attributable to undiagnosed individuals in 2024 ranged from 29·8% to 64·6% across the models and the proportion of transmissions attributable to individuals who had interrupted treatment ranged from 4·7% to 21·5%. In South Africa, 21·8–46·4% of transmissions in 2024 were attributable to undiagnosed individuals and 27·6–58·9% of transmissions were attributable to individuals who had interrupted treatment.
Interpretation
Across the three study settings, a substantial proportion of new HIV transmissions were attributable to undiagnosed individuals and people who have received interrupted ART, reinforcing the importance of continuing HIV testing and ART re-engagement and retention interventions.
Funding
The Bill & Melinda Gates Foundation