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Large-scale epidemiology of opisthorchiasis in 21 provinces in Thailand based on diagnosis by fecal egg examination and urine antigen assay and analysis of risk factors for infection
No full textIntroduction
Infection with the carcinogenic fish-borne trematode Opisthorchis viverrini, known as opisthorchiasis, is a major cause of biliary cancer (cholangiocarcinoma). Despite decades of disease prevention and control in Thailand, the parasite remains endemic. Here we apply a novel antigen assay for mass screening of opisthorchiasis and compare the prevalence against the conventional examination and analyze risk factors associated with current O. viverrini infection.
Materials and methods
We conducted a large-scale cross-sectional survey to assess transmission of O. viverrini in the North, Northeast, and Eastern regions of Thailand. We screened randomly selected people (age 15 years and over) in 23 sub-districts, within 21 provinces, with a target sample size of 1,000 per sub-district. Each participant was screened for multiple helminth infection by fecal examination (quantitative formalin-ethyl acetate concentration technique; FECT), and the antigen assay by monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) was applied to urine samples to detect O. viverrini. We collected risk factors for O. viverrini infection using standardized questionnaire surveys. The data were analyzed with regression models which correlated individual-level explanatory variables against i) infection status with O. viverrini and ii) the intensity of infection, as measured by the antigen assay or FECT.
Findings
Of the 20,322 individuals enrolled, 19,465 provided urine samples for antigen detection by ELISA and 18,929 provided fecal samples for examination by FECT. The urine antigen assay revealed an overall opisthorchiasis prevalence of 50.3%, a fourfold increase over the 12.2% prevalence detected by FECT. Marked spatial heterogeneity was observed, with antigen‐based prevalence estimates ranging from 22.2% to 71.4% and several localities exceeding 60%. When assessed against a composite reference standard (combined ELISA and FECT), the urine ELISA yielded a diagnostic sensitivity of 91.6%, compared with 21.9% for FECT. We found a positive correlation between fecal egg counts and the concentration of worm antigen in urine across study sites. The ratio between the prevalence of O. viverrini observed by the antigen assay and FECT was high in provinces with a low mean number of O. viverrini eggs, and the ratio approached unity as the mean eggs per gram of stool (EPG) increased. Similar aggregate distribution patterns of fecal egg counts (EPG) and urine antigen concentrations suggest that the urine assay has potential for quantitative diagnostic evaluations. When analyzing individual-level risk factors, we further identified age, sex, occupation, a history of prior treatment with praziquantel, history of O. viverrini examination, and raw fish consumption as predictive of infection with O. viverrini, while a higher education level and certain occupations emerged as protective factors.
Conclusions and recommendations
Application of the antigen assay to diagnose O. viverrini infection yielded a four-fold higher prevalence than the fecal egg examination, with the highest difference in low endemicity regions, which suggests that previous surveys may have underestimated the extent of opisthorchiasis in Thailand. Given the ease of urine sample collection, our study highlights the potential for application of the antigen assay as a new tool in the control of opisthorchiasis
"Walking a day in my shoes": a clinical shadowing program to enhance medical students' understanding of chronic disease management beyond clinical settings
No full textAIMS/BACKGROUND: Medical education is largely clinical and biomedical with little emphasis being put upon the social determinants of health (SDH) and patient-centredness. A programme entitled "Walking a Day in My Shoes" was devised as a pilot cohort study with the view of evaluating the impact of a clinical shadowing experience upon the empathy, SDH awareness, and patient-centredness of medical students. METHODS: A prospective cohort study, involving 28 final-year London-area medical students, employing a three-phase teaching programme comprising preparation, observation, and reflection was carried out. Students' confidence in the management of non-medical barriers, SDH awareness, and empathy before and after shadowing were measured using pre- and post-shadowing questionnaires. Qualitative analysis of patient feedback and journals also occurred. RESULTS: Statistically significant improvements were observed in students' empathy (mean score increase from 6.8 to 8.9, p < 0.001), understanding of SDH (advanced comprehension rose from 35% to 93%), confidence in addressing non-clinical barriers (from 39% to 86%), and awareness of logistical challenges (from 31% to 81%). Qualitative analysis highlighted key themes, including systemic barriers (transportation, polypharmacy, and social isolation) and students' increased awareness of the emotional toll of chronic illness. Patients expressed high satisfaction, with 97% agreeing that the programme improved students' understanding of chronic disease management. These findings suggest the programme's practicality and scalability in medical education. CONCLUSIONS: This pilot cohort study demonstrated the significant enhancement of the students' empathy, perception of SDH, and patient-centredness preparation through immersive shadowing. The findings support the use of experiential learning programmes as curricular interventions
Determining the minimum important differences for field walking tests in adults with long–term conditions: a systematic review and meta-analysis
No full textImportance
The minimum important difference (MID) for field walking tests aims to improve interpretation of outcomes, but the volume and heterogeneity of MIDs for these tests is challenging. We aimed to determine the MID for the 6-min walk distance (6MWD), incremental shuttle walk test (ISWT) and endurance shuttle walk test (ESWT) in adults with long-term conditions.
Methods
This systematic review included studies that generated a MID using an anchor-based approach in patients with long-term conditions for the 6MWD, ISWT or ESWT field walking tests. Studies were screened and data extracted by independent reviewers. Meta-analyses were performed using RevMan.
Results
42 studies were included in the analyses, involving n=13 949 participants. Of these, 12 studies involving exercise as an intervention were included in the meta-analyses to produce MIDs, presented as mean (95% confidence interval). The MID for the 6MWD was 25 m (24–26 m) for respiratory conditions, 23 m (8–37 m) for cardiac conditions and 37 m (26–49 m) for neurological/musculoskeletal conditions. The MID for the ISWT was 48 m (39–57 m) for respiratory conditions and 70 m (55–85 m) for cardiac conditions. The MID for ESWT in COPD was 159 s (94–224 s). The pooled MID across conditions within exercise interventions was 26 m (22–40 m) for the 6MWD and 53 m (44–62 m) for the ISWT, with reasonable heterogeneity (I2=48% and I2=47%, respectively).
Conclusion
We propose new MIDs for exercise interventions using anchor-based methodology in long‑term conditions for the 6MWD, ISWT and ESWT. These can be used internationally for meta‑analyses where studies have used different field walking tests, to optimise trial sample size calculations, and for clinical service benchmarking
An individual-based modelling study estimating the impact of maternity service delivery on health in Malawi
No full textMaternal and perinatal morbidity and mortality remain high in Malawi, partially due to gaps in the coverage and quality of health services. We developed an individual-based model of maternal and perinatal health and healthcare in Malawi, situated in a ‘whole-health system, all-disease’ framework (Thanzi La Onse). We modelled sixteen scenarios estimating the impact of current and improved coverage and quality of antenatal, intrapartum, and postnatal services from 2023 to 2030. Whilst current service delivery is inferred to avert morbidity and mortality, the largest reductions in the stillbirth, maternal and neonatal mortality rates were observed when the use and quality of all services was maximised concurrently (a 10%, 52% and 57% reduction respectively). When services were considered in isolation, generally, increased coverage without quality improvement did not impact mortality or DALYs. In only three scenarios was a sufficient reduction in neonatal mortality observed to achieve target 3.2 of the United Nation’s Sustainable Development Goals (SDG), and in no scenarios was a reduction in maternal mortality sufficient to achieve SDG target 3.1 observed, reaffirming that system wide investments are essential to achieve these goals
Analytical modelling of structural instabilities: Recent developments and outlook
No full textAnalytical modelling of structural elements susceptible to instabilities, such as thin-walled metallic components, laminated composite panels and metamaterial lattices, has recently provided fresh insights to their nonlinear behaviour. The present overview highlights some of the advantages of analytical approaches for interpreting the mechanical response of such problems in physical structures. The results from this kind of modelling, in particular for components with perfect geometries that exhibit complex instability phenomena, can provide highly valuable and in fact more generic information that can complement standard high-fidelity finite element (FE) modelling. This is because some of the necessary procedures within standard FE modelling can obscure some of the mechanical richness in the behaviour, which in turn can be readily interpreted through analytical techniques. In the present context, a series of recent studies are outlined that comprise investigations on buckling mode interaction in thin-walled metal and composite structural components, the internal buckling of mechanical metamaterials and the real-time assessment of in-situ compression members through probing and machine learning. Through these examples, the aim is to illustrate that analytical modelling still has an invaluable role to play in structural mechanics and engineering
Can tropical cyclones exist near the Equator?
No full textTropical cyclones (TCs) rarely form within about 5 degrees of latitude of theEquator due to the weak Coriolis force, yet it is not clear how a weak Coriolisforce would affect an already developed TC vortex. In this study, a set of Cori-olis parameter (f ) sensitivity experiments are applied to a well-developed TCvortex in idealized simulations by decreasing f to zero, both abruptly and grad-ually. The simulated TCs weaken due to the reduction of f . However, dependingon the initial intensity, it can take several days for the TC to decay to a tropicalstorm. Both radial inflow and outflow strengthen throughout the cyclone depth,because of decreasing inertial stability and increasing agradient force associ-ated with reduced f . This further causes a deeper inflow layer and strengtheneddowndrafts associated with convection in the outer rainbands. The downdraftentrainment of mid-level dry air into the deeper inflow layer stabilizes theboundary layer and suppresses deep convection, ultimately resulting in theweakening of TCs. Although TCs are not formed readily near the Equator, if theyare steered there they could potentially exist long enough to cause damage
Protocol for a group-sequential two-stratum multicenter open-label randomized clinical trial of respiratory support in infants with acute bronchiolitis: breathing assistance in children with bronchiolitis (BACHb)
No full textOBJECTIVES:
The Breathing Assistance in Children with bronchiolitis (BACHb) trial aims to evaluate the clinical and cost-effectiveness of high-flow nasal cannula (HFNC) therapy compared with humidified standard oxygen (HSO) in infants with moderate bronchiolitis, and HFNC with continuous positive airway pressure (CPAP) in severe bronchiolitis.
DESIGN:
Pragmatic, group-sequential, two-stratum, multicenter, open-label randomized clinical trial.
SETTING:
Fifty hospitals across England, Scotland, and Wales.
PATIENTS:
Hospitalized infants younger than 12 months old with a clinical diagnosis of bronchiolitis, assessed at least twice 15 minutes apart to fulfill criteria for either severe bronchiolitis (one or more of: respiratory rate > 70 breaths/min, grunting, marked chest recession, recurrent short apneas) or moderate bronchiolitis (lack of response to low-flow oxygen, indicated by persistent hypoxemia and/or moderate respiratory distress).
INTERVENTIONS:
“Moderate bronchiolitis stratum”: HFNC at a flow rate of 2 L/kg/min vs. HSO through a facemask or headbox at a flow rate up to 15 L/min. “Severe bronchiolitis stratum”: HFNC at a flow rate of 2 L/kg/min vs. CPAP pressure set at 6–8 cm H2O.
MEASUREMENTS AND MAIN RESULTS:
In each stratum, eligible infants will be randomly allocated on a 1:1 basis to the trial treatments using a web-based system by permuted block randomization, stratified by site of recruitment and age (< 6 wk and ≥ 6 wk). Due to the emergency nature of the treatments, written informed consent will be deferred. The primary outcome is time from randomization to hospital discharge within 30 days. Baseline clinical characteristics and hospital course, including details of respiratory support, and discharge and cost-effectiveness outcomes will be collected. The trial received Health Research Authority and Research Ethics Committee approval from the Yorkshire and The Humber—South Yorkshire Research Ethics Committee on August 3, 2023 (reference: 23/YH/0166). The trial registration is ISRCTN52937119.
CONCLUSIONS:
Trial findings will be disseminated in national and international conferences, in peer-reviewed journals and through social media
Evaluating uncertainty quantification methods in argumentative large language models
No full textResearch in uncertainty quantification (UQ) for large language models (LLMs) is increasingly important towards guaranteeing the reliability of this groundbreaking technology. We explore the integration of LLM UQ methods in argumentative LLMs (ArgLLMs), an explainable LLM framework for decision-making based on computational argumentation in which UQ plays a critical role. We conduct experiments to evaluate ArgLLMs’ performance on claim verification tasks when using different LLM UQ methods, inherently performing an assessment of the UQ methods’ effectiveness. Moreover, the experimental procedure itself is a novel way of evaluating the effectiveness of UQ methods, especially when intricate and potentially contentious statements are present. Our results demonstrate that, despite its simplicity, direct prompting is an effective UQ strategy in ArgLLMs, outperforming considerably more complex approaches
Projected tropical cyclone genesis and seasonality changes in the Northern Hemisphere under a warming climate
No full textThe impact of global warming on future tropical cyclone (TC) development is substantial; however, the predictability of TC genesis remains uncertain. In this study, we investigate projected changes in TC genesis on a regional scale over the North Atlantic (NA) and western North Pacific (WNP) ocean basins, focusing on TC seasonality through bias-corrected model simulations. Our study unveils a weakening of peak TC genesis (August-October; ASO) at lower latitudes under a high-emission scenario, along with a strengthening of TC peak (July-September; JAS) at higher latitudes. Most importantly, positive vertical velocity (ω) in the mid-troposphere (500 hPa) plays a dominant role in weakening the TC peak in the tropics, while weak vertical wind shear (VWS) in the subtropics facilitates TC development. Our study elucidates the impact of climate change on the regional environment and the ensuing possible changes in TC seasonality, offering essential insights into future projected TC genesis in the Northern Hemisphere
Bayesian neural network (BNN) machine learning (ML) surrogate modelling methods for simulating turbulent flow within nuclear power plant (NPP) t-junction pipes
No full textThe integration of nuclear power plants (NPPs) into modern smart grids poses new challenges, particularly in ensuring component reliability under increasingly dynamic operating conditions. One area of concern is thermal fatigue in T-junctions within the primary circuit, which is a critical issue for nuclear safety that remains poorly addressed by current modelling practices. Existing approaches often focus on isolated components or employ low-fidelity models, limiting their ability to capture the complex flow-induced thermal stresses that drive thermal fatigue. This research addresses these limitations through a three-part investigation. First, mesh discretisation error within the computational models are thoroughly studies and estimated. This provides significant insights into how model accuracy can be improved, while concurrently providing model uncertainty estimates. The second would be developing a high-fidelity simulation framework to model turbulent flow in various T-junction configurations. Using Power Spectral Density (PSD), Proper Orthogonal Decomposition (POD), and Spectral POD (SPOD), the study identifies dominant flow structures responsible for thermal fatigue. These analyses provide detailed insights into unsteady flow behaviours that are often overlooked in traditional models. Results reveal underlying flow structures within turbulent flow that potentially contributes to thermal fatigue phenomena. Third, machine learning techniques are explored to recover turbulent flow features in these geometries. Several neural network architectures such as deep neural networks (DNNs), physics-informed neural networks (PINNs), Bayesian neural networks (BNNs), and Bayesian PINNs (BPINNs), are evaluated as surrogate models for flow field reconstruction. Results show that BNNs achieve the best performance, providing both accurate predictions and quantified uncertainty. This positions it as a valuable component in the broader effort to enhance predictive capabilities in nuclear thermal fatigue analyses.Open Acces