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Are Models of Strong Gravitational Lensing by Clusters Converging or Diverging?
No full textThe increasingly large numbers of multiple images in cluster-scale gravitational lenses have allowed for tighter constraints on the mass distributions of these systems. Most lens models have progressed alongside this increase in image number. The general assumption is that these improvements would result in lens models converging to a common solution, suggesting that models are approaching the true mass distribution. To test whether or not this is occurring, we examine a sample of lens models of MACS J0416.1−2403 containing varying number of images as input. Splitting the sample into two bins (those including 150 images), we quantify the similarity of models in each bin using three comparison metrics, two of which are novel: Median Percent Difference, Frechet Distance, and Wasserstein Distance. In addition to quantifying similarity, the Frechet distance metric seems to also be an indicator of the mass sheet degeneracy. Each metric indicates that models with a greater number of input images are no more similar between one another than models with fewer input images. This suggests that lens models are neither converging nor diverging to a common solution for this system, regardless of method. With this result, we suggest that future models more carefully investigate lensing degeneracies and anomalous mass clumps (mass features significantly displaced from baryonic counterparts) to rigorously evaluate their model's validity. We also recommend further study into alternative, underutilized lens model priors (e.g. flux ratios) as an additional input constraint to image positions in hopes of breaking existing degeneracies
Sufficiency and consistency of antenatal care services in Ethiopia: Evidence from Mini Ethiopian demographic and health survey
No full textBackground Antenatal care plays a critical role in promoting the health of mothers and infants. In Sub-Saharan Africa, about 76% of women accessing at least one visit. However, rural areas in Ethiopia face more significant challenges, including traditional beliefs, geographical distance, and the need for more awareness. Despite advancements, ensuring quality ANC for all women necessitates targeted interventions. There are needs of evidence regarding adequacy and consistency ANC services in different regions of Ethiopia. Therefore, study aimed to evaluate and compare the adequacy and consistency of ANC services across various regions in Ethiopia. Methods Data for the 2019 Mini Ethiopia Demographic and Health Survey (Mini EDHS) were collected using a cross-sectional study design. The survey included 2,918 women aged 15-49 from various regions of Ethiopia. Data analysis was carried out using STATA version 14. Descriptive statistics, such as frequencies and percentages, were used to present the background characteristics of the participants. To assess the significance of variations and associated factors, a logistic regression model was applied. Variables with a p-value of 0.25 or less in the bivariate analysis were included in the multivariable analysis. A significance level of p < 0.05 and a 95% confidence interval were used to determine the significance of the variables. Results The study surveyed 2,918 women aged 15-49, with 70.7% receiving antenatal care (ANC) from a skilled provider. Among them, 56.8% had four or more visits, and 43% started care in the first trimester. Overall, 35.8% received all routine ANC components, and 14.7% received adequate ANC services. ANC adequacy varied by region, with the highest in Addis Ababa (39.1%) and lowest in SNNPR (6.2%). About 72% of women received consistent ANC, with Addis Ababa showing the highest consistency (54.2%). Logistic regression analysis found that education status, region, wealth status, and literacy were significant factors influencing ANC adequacy. Regional disparities showed lower ANC adequacy in Oromia, Benishangul, SNNPR, and Gambela compared to Tigray. Wealthier women and those with secondary or higher education were more likely to receive consistent ANC. Conclusion The study underscored the significant impact of regional disparities, financial constraints, education levels, and geographic location on the unequal access to and quality of antenatal care (ANC) services in Ethiopia. Promoting ANC utilization, especially among women with lower education and economic disadvantages, was identified as a key priority. The study recommends targeted interventions to address service gaps for less-educated women and highlights the need for focused efforts to reduce regional disparities in both the adequacy and consistency of ANC services.The authors would like to thank the Demographic Health Survey program office for providing the needed data for this study and Jimma University for providing the internet
Structuring Empirical Research on Process Mining at the Individual Level Using the Theory of Effective Use
No full textA growing number of empirical papers on the topic of process mining has been published in years. After a first wave of contributions on application scenarios, there has been a second wave aiming to establish theoretical insights into how process mining tools are used and how benefits unfold from this usage. Many of these papers follow an explorative, qualitative, or inductive approach. A weakness of these contributions is their theoretical cohesion and integration. This paper makes an effort to integrate them into a more holistic theory that can eventually provide a foundation for more deductive and quantitative empirical research on process mining. To this end, we build on the theory of effective use and focus on the individual effect on decision makers. We find opportunities for revision and refinement of this theory for process mining. Specifically, we discuss moving from constructs on learning to expertise, and integrating a pragmatic perspective that complements the semantic emphasis of representational fidelity.The research of the authors was supported by the Einstein Foundation Berlin under grant EPP-2019-524, by the German Federal Ministry of Education and Research under grant 16DII133, and by Deutsche Forschungsgemeinschaft under grants 496119880 (VisualMine) and 531115272 (ProImpact)
Back-to-Back, a proof of concept study investigating the role of back muscle characteristics to tailor exercise therapy for recurrent non-specific low back pain: study protocol and preliminary analysis of proprioceptive postural control results
No full textBackground and aim
Non-specific low back pain (NSLBP) is the main cause of disability worldwide and current treatments have limited effects. Alterations in macroscopic, microscopic, electrophysiological and hemodynamic lumbar muscle characteristics and proprioceptive postural control (PPC) are found in people with NSLBP and directing treatment based on shared underlying mechanisms (phenotypes), could improve its effects. Therefore, this study aims to determine the most discriminating lumbar muscle characteristics between patients with NSLBP and healthy controls, investigate their interrelatedness and relationship with PPC and delineate NSLBP phenotypes based on them. Additionally, to investigate whether proprioceptive exercises have a greater effect on specific NSLBP phenotypes.
Methods
Lumbar multifidus and erector spinae muscle characteristics will be evaluated and compared in 53 people with recurrent NSLBP and 47 healthy controls. For PPC, the COP displacements in response to vibration to the ankle and back muscles are measured on a force plate, while standing on stable and unstable surface with vision occluded. Proprioceptive dominance is evaluated by the Relative Proprioceptive Weighting (RPW) ratio, with lower RPW values indicating more lumbar proprioceptive reliance. Muscle volume is investigated with 3D freehand ultrasound, and muscle activation and oxygenation with electromyography and near-infrared spectroscopy, respectively. The 53 people with NSLBP also receive a 16-week intervention focusing on improving their ability to sense and discriminate low back position, muscle activation and lumbar movement. These proprioceptive exercises are integrated into the patients’ daily lives and comprise a high-load lifting exercise. Their effects are evaluated at 8 weeks, 16 weeks and 16 weeks after the end of the intervention.
Results
Recruitment is ongoing, currently five people with recurrent NSLBP are enrolled and analysed descriptively. Preliminary results on PPC include increased lumbar proprioceptive reliance after eight (Pre: 0.69 ± 0.04; Post: 0.46 ± 0.30 stable and Pre: 0.58 ± 0.13; Post: 0.44 ± 0.31 unstable) and 16 weeks (Post: 0.40 ± 0.30 stable and Post: 0.34 ± 0.16 unstable) and increased COP displacement in response to lumbar vibration on stable (Pre: 0.018 ± 0.011; Post: 0.020 ±0.012) and unstable (Pre: 0.015 ± 0.013; Post: 0.021 ± 0.009) after 16 weeks of intervention.
Conclusion
Preliminary results show increased lumbar proprioceptive use and a switch in dominant reliance from ankle to lumbar proprioception in response to this proprioceptive intervention, translating to improved PPC. Further effects on the different lumbar muscle characteristics and their correlation with PPC will be investigated. Phenotypes of people with NSLBP will be delineated and the effects of this intervention on them will be examined. Results may improve patient-tailored exercise therapy for people with NSLBP.Research Foundation Flanders (FWO) - grant numbers 11B6522N and G072122
Thermodynamics of underdamped Brownian collisional engines: General features and resonant phenomena
No full textCollisional Brownian engines have been proposed as alternatives to nonequilibrium nanoscale engines. However, most studies have focused on the simpler overdamped case, leaving the role of inertia much less explored. In this work, we introduce the idea of collisional engines to underdamped Brownian particles, where at each stage the particle is sequentially subjected to a distinct driving force. A careful comparison between the performance of underdamped and overdamped Brownian work-to-work engines has been undertaken. The results show that underdamped Brownian engines generally outperform their overdamped counterparts. A key difference is the presence of a resonant regime in underdamped engines, in which both efficiency and power output are enhanced across a broad set of parameters. Our study highlights the importance of carefully selecting dynamics and driving protocols to achieve optimal engine performance.The authors acknowledge financial support from CNPq and FAPESP under Grants No. 2021/03372-2, No. 2022/16192-5, No. 2022/15453-0, and No. 2024/03763-0
Microplate-based impedance and thermal sensing system for concurrent cell viability and counting analysis
No full textCell count and viability are critical parameters in biological research, drug discovery, and bioprocessing. Traditional methods for assessing these metrics often rely on destructive, end-point analyses. This research presents a novel multi-parameter sensing platform that enables concurrent analysis of cell viability and count in a microplate format. The platform combines thermal-based and impedance-based sensing to harness the distinct responses of these methods to variations in cell number and viability. Crucially, both techniques are influenced by cell viability and count, but to different degrees. This difference in sensitivity allows for the exploitation of both methods to independently assess these parameters. Thermal sensing primarily quantifies cell biomass, while impedance measurements are more sensitive to membrane integrity changes associated with cell viability. The integration of these sensing elements into a standard microwell format facilitates real-time and label-free measurements. Experiments with Saccharomyces cerevisiae cultures at various concentrations and viability states demonstrated the platform's capabilities. Multivariate regression models were developed to independently predict cell number and viability, achieving root mean square errors of 0.106 x107 cells and 19.67% viability respectively. Notably, performance improved at higher cell concentrations, with viability prediction error reduced to 5.02%. This integrated approach shows promise for continuous, non-destructive monitoring of cell cultures, offering a cost-effective alternative to traditional end-point analysis methods. The platform's ability to provide real-time insights into cell population dynamics could significantly enhance various applications in biotechnology, including bioprocess optimization, drug screening, and toxicity testing. Furthermore, its compatibility with standard microplate formats facilitates easy integration into existing laboratory workflows.This work was supported and funded by Fonds Wetenschappelijk Onderzoek (FWO) – Vlaanderen (1SD7923N).
The authors would like to thank the Biomedical Research Institute at UHasselt (BIOMED) for providing the FACS analysis. They would also like to thank Dieter Reenaers for the assistance in microscopy analysis and cell counting of cell cultures. Additionally, they would like to thank Kato Nelissen for the preliminary measurements and valuable insight
Estimating social contact rates for the COVID-19 pandemic using Google mobility and pre-pandemic contact surveys
No full textDuring the COVID-19 pandemic, aggregated mobility data was frequently used to estimate changing social contact rates. By taking pre-pandemic contact matrices, and transforming these using pandemic-era mobility data, infectious disease modellers attempted to predict the effect of large-scale behavioural changes on contact rates. This study explores the most accurate method for this transformation, using pandemic-era contact surveys as ground truth. We compared four methods for scaling synthetic contact matrices: two using fitted regression models and two using "na & iuml;ve" mobility or mobility squared models. The regression models were fitted using the CoMix contact survey and Google mobility data from the UK over March 2020-March 2021. The four models were then used to scale synthetic contact matrices-a representation of pre-pandemic behaviour-using mobility data from the UK, Belgium and the Netherlands to predict the number of contacts expected in "work" and "other" settings for a given mobility level. We then compared partial reproduction numbers estimated from the four models with those calculated directly from CoMix contact matrices across the three countries. The accuracy of each model was assessed using root mean squared error. The fitted regression models had substantially more accurate predictions than the na & iuml;ve models, even when models were applied to out-of-sample data from the UK, Belgium and the Netherlands. Across all countries investigated, the linear fitted regression model was the most accurate and the na & iuml;ve model using mobility alone was the least accurate. When attempting to estimate social contact rates during a pandemic without the resources available to conduct contact surveys, using a model fitted to data from another pandemic context is likely to be an improvement over using a "na & iuml;ve" model based on mobility data alone. If a na & iuml;ve model is to be used, mobility squared may be a better predictor of contact rates than mobility per se.This research was conducted as part of the first authors (Em Prestige) pre-doctoral fellowship funding by the National Institute for Health and Care Research (NIHR); grant number: NIHR301994. Funders did not play any role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. Em Prestige is funded by the National Institute for Health Research (NIHR) Health Protection Research Unit in Modelling and Health Economics, a partnership between the UK Health Security Agency, Imperial College London and LSHTM (grant code NIHR200908). Disclaimer: “The views expressed are those of the author(s) and not necessarily those of the NIHR, UK Health Security Agency or the Department of Health and Social Care.
Statistical methods for analyzing infectious diseases using social contact data
No full textAbstract not available
Generalized Pairwise Comparisons to Support Shared Decision-Making in the CODA Trial
No full textImportance Shared decision-making (SDM) can be made difficult by the multifaceted nature of outcome assessment. A rigorous method for analyzing results from multiple outcomes is called generalized pairwise comparisons (GPC), which could assist in SDM. Objective To examine whether GPC can be useful in SDM by using individual-patient data from the Comparison of Outcomes of Antibiotic Drugs and Appendectomy (CODA) trial. Design, Setting, and Participants This comparative effectiveness study used data from participants in the multicenter US CODA trial (conducted between May 2016 and March 2020). All possible pairs of patients (one from each arm) were formed to analyze each of 7 outcomes of interest sequentially. Data were analyzed between February 2020 and early 2024. Exposures Three scenarios of priorities related to a different order of outcomes were considered. The first scenario came from a consensus exercise with patients that favored antibiotics, whereas the other 2 were arbitrarily chosen to illustrate the range of possible outcomes depending on prioritizations. Scenario 2 favored neither treatment, and scenario 3 favored appendectomy. Main Outcomes and Measures The primary outcome was the net treatment benefit (NTB), a formal measure of benefit-risk, which is the net probability that a randomly selected patient from the antibiotic-assigned arm would have a more favorable outcome than a randomly selected patient from the appendectomy-assigned arm. Results A total of 1552 patients were included in the CODA trial, with 776 (mean [SD] age, 38.3 [13.4] years; 286 [37%] female) in the antibiotic arm and 776 (mean [SD] age, 37.8 [13.7] years; 290 [37%] female) in the appendectomy arm. The NTB of antibiotic treatment was 12.8% (95% CI, 7.1% to 18.3%; P < .001) for the first scenario, 3.2% (95% CI -2.4% to 8.7%; P = .27) for the second, and -14.5% (95% CI. -20.2% to -8.8%; P < .001) for the third. These results respectively favored antibiotics, neither treatment, or appendectomy, thus illustrating that benefit-risk varies considerably according to individual priorities. Conclusions and Relevance This comparative effectiveness study of antibiotics and appendectomy illustrates that the GPC method is a flexible yet mathematically rigorous quantitative analysis of benefit-risk balance. This method provides a more exhaustive and nuanced quantitative assessment of the differences between 2 treatment modalities in terms of prioritized outcomes. Furthermore, GPC could support SDM by considering individual prioritizations of the multiple outcomes.This comparative effectiveness study used patient-level data from a randomized clinical trial comparing the outcomes of antibiotics vs appendectomy. Using generalized
pairwise comparison, the net treatment benefit significantly favored antibiotics, was neutral, or significantly favored appendectomy, depending on the patient’s order of priority.
This work was supported in part by the Government ofWallonia, Belgium (BioWin Consortium Agreement No. 7979). The CODA Trial was funded by a PCORI Award (No. 1409-240099)
Enhanced Recovery After Craniotomy: Global Practices, Challenges, and Perspectives
No full textThe global demand for hospital care, driven by population growth and medical advances, emphasizes the importance of optimized resource management. Enhanced Recovery After Surgery (ERAS) protocols aim to expedite patient recovery and reduce health care costs without compromising patient safety or satisfaction. Its principles have been adopted in various surgical specialties but have not fully encompassed all areas of neurosurgery, including craniotomy. ERAS for craniotomy has been shown to reduce the length of hospital stay and costs without increasing complications. ERAS protocols may also reduce postoperative nausea and vomiting and perioperative opioid requirements, highlighting their potential to enhance patient outcomes and health care efficiency. Despite these benefits, guidelines, and strategies for ERAS in craniotomy remain limited. This narrative review explores the current global landscape of ERAS for craniotomy, assessing existing literature and highlighting knowledge gaps. Experts from 26 countries with diverse cultural and socioeconomic backgrounds contributed to this review, offering insights about current ERAS protocol applications, implementation challenges, and future perspectives, and providing a comprehensive global overview of ERAS for craniotomy. Representatives from all 6 World Health Organization geographical world areas reported that barriers to the implementation of ERAS for craniotomy include the absence of standardized protocols, provider resistance to change, resource constraints, insufficient education, and research scarcity. This review emphasizes the necessity of tailored ERAS protocols for low and middle-income countries, addressing differences in available resources. Acknowledging limitations in subjectivity and article selection, this review provides a comprehensive overview of ERAS for craniotomy from a global perspective and underscores the need for adaptable ERAS protocols tailored to specific health care systems and countries