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Model-based static compliance analysis and control for pneumatic-driven soft robots
No full textElastomer-based soft manipulators have been explored in various fields due to their inherent compliant properties. Understanding and regulation of robot's compliance are important to the design, modeling, and control of soft robots. However, the elastomers are nonlinear hyperelastic materials with distributed compliance. This property makes the compliance modeling and control of soft robots fundamentally different and more complex from their rigid counterparts. This article presents a neo-Hookean model-based compliance modeling and control approach to investigate and regulate the configuration-dependent compliance property of a pneumatic-driven soft manipulator. The neo-Hookean model is used to derive the stretch ratio and update the tangent modulus of materials. The robot's compliance is obtained by integration with the forward kinematics building on the static Cosserat rod model. The derived compliance matrix is utilized to regulate robot's compliance along the x-, y-, and z-axes. Computational and experimental validation demonstrate high fidelity of the proposed approach. Moreover, experiments illustrate that the exhibited robot's compliance can be regulated up to 49.5% higher or 34.2% lower compared to inherent robot's compliance. The proposed model-based compliance control strategy has also demonstrated its effectiveness in enhancing grasping ability when implemented on a soft gripper
Compliance to tobacco and alcohol zoning regulations around schools in Bangladesh, India, Pakistan and Sri Lanka using environmental mapping data
No full textBackground
The built environment around schools that are regularly accessed by young people is determined by governments, national and regional policies in each country or region. Zoning regulations for tobacco and alcohol sales are expected to restrict availability and access by young people. This study aimed to examine (non) compliance with tobacco and alcohol zoning regulations around schools in Bangladesh, India, Pakistan and Sri Lanka.
Methods
In a representative sample of geographic locations in Bangladesh, India North (Delhi) and India South (Chennai), Pakistan and Sri Lanka, the built environment was mapped by systematically walking all streets within the site boundary to collect data on different types of tobacco and alcohol retailers and schools. Data was collected on KoboToolBox, and the maps indicating zoning compliance were created using ArcGIS. Descriptive analysis of outlet compliance to the zoning laws was conducted at the national and school levels, with heterogeneity analyses done by school type, income level and outlet type for tobacco and alcohol.
Results
The zoning regulations for tobacco and alcohol differed among the settings ranging from 50 to 100 m for tobacco and absolute bans to 500 m for on-premise alcohol. Among the five different settings within the four countries, 441 areas were studied, including 3615 schools. Non-compliance with the zoning laws is evident in all jurisdictions for both tobacco and alcohol. Within restricted zones around schools (location non-compliant with zoning laws), 12–38% of outlets selling tobacco and 16% to 100% of outlets selling alcohol were identified. For supply non-compliance, 3–70% of shops within the school buffer zones were selling tobacco, while only 0.2–1% of shops were selling alcohol.
Conclusions
Non-compliance with tobacco and alcohol zoning regulations has been observed around schools in Bangladesh, India (North and South), Pakistan and Sri Lanka. Within each country, there was a higher percentage of alcohol outlets that were location non-compliant than for tobacco, except for South India. In India and Sri Lanka, there was a higher percentage of supply non-compliance for tobacco than alcohol. This study calls for governments to strictly enforce existing zoning regulations that are expected to restrict access to tobacco and alcohol for young people
Experimental demonstration of generalized quantum fluctuation theorems in the presence of coherence
No full textFluctuation theorems have elevated the second law of thermodynamics to a statistical realm by establishing a connection between time-forward and time-reversal probabilities, providing invaluable insight into nonequilibrium dynamics. While well established in classical systems, their quantum generalization, incorporating coherence and the diversity of quantum noise, remains open. We report the experimental validation of a quantum fluctuation theorem (QFT) in a photonic system, applicable to general quantum processes with nonclassical characteristics, including quasi-probabilistic descriptions of entropy production and multiple time-reversal processes. Our experiment confirms that the ratio between the quasi-probabilities of the time-forward and any multiple time-reversal processes obeys a generalized Crooks QFT. Moreover, coherence induced by a quantum process leads to the imaginary components of quantum entropy production, governing the phase factor in the QFT. These findings underscore the fundamental symmetry between a general quantum process and its time reversal, providing an elementary toolkit to explore noisy quantum information processing
Estimating the potential impact of surveillance test-and-treat posts to reduce malaria in border regions in sub-Saharan Africa: a modelling study
No full textBackground:
The last malaria cases in near-elimination settings are often found in international border regions due to the presence of hard-to-reach populations, conflict, uneven intervention coverage, and human migration. Test-and-treat border posts are an under-researched form of active case detection used to interrupt transmission chains between countries.
Methods:
An individual-based, mathematical metapopulation model of Plasmodium falciparum was used to estimate the effectiveness of border screening posts on total cases in malaria-endemic sub-Saharan Africa.
Results:
The implementation of international border posts across 401 sub-national administrative units would avert a median of 7173 (IQR 1075 to 23,550) cases per unit over a 10 year period and reduce PfPR2-10 by a median of 0.21% (IQR 0.04 to 0.44%).
Conclusions:
Border posts were most effective in low-transmission settings with high-transmission neighbours. Border posts alone in sub-Saharan Africa will not allow a country to reach elimination, particularly when considering feasibility and acceptability, but could contribute to broader control packages to targeted populations
An automated hip fracture detection, classification system on pelvic radiographs and comparison with 35 clinicians
No full textAccurate diagnosis of orthopedic injuries, especially pelvic and hip fractures, is vital in trauma management. While pelvic radiographs (PXRs) are widely used, misdiagnosis is common. This study proposes an automated system that uses convolutional neural networks (CNNs) to detect potential fracture areas and predict fracture conditions, aiming to outperform traditional object detection-based systems. We developed two deep learning models for hip fracture detection and prediction, trained on PXRs from three hospitals. The first model utilized automated hip area detection, cropping, and classification of the resulting patches. The images were preprocessed using the Contrast Limited Adaptive Histogram Equalization (CLAHE) algorithm. The YOLOv5 architecture was employed for the object detection model, while three different pre-trained deep neural network (DNN) architectures were used for classification, applying transfer learning. Their performance was evaluated on a test dataset, and compared with 35 clinicians. YOLOv5 achieved a 92.66% accuracy on regular images and 88.89% on CLAHE-enhanced images. The classifier models, MobileNetV2, Xception, and InceptionResNetV2, achieved accuracies between 94.66% and 97.67%. In contrast, the clinicians demonstrated a mean accuracy of 84.53% and longer prediction durations. The DNN models showed significantly better accuracy and speed compared to human evaluators (p < 0.0005, p < 0.01). These DNN models highlight promising utility in trauma diagnosis due to their high accuracy and speed. Integrating such systems into clinical practices may enhance the diagnostic efficiency of PXRs
Survival in patients receiving reduced dose intensity of bevacizumab for unresectable hepatocellular carcinoma
No full textIMBrave 150 established atezolizumab and bevacizumab as the new standard for advanced hepatocellular carcinoma (HCC) treatment. However, the trial reported significant adverse events leading to bevacizumab dose interruptions or discontinuations. This retrospective, real-world analysis evaluated the effect of reduced bevacizumab dose intensity on clinical outcomes in 354 patients receiving first-line combination immunotherapy for advanced HCC. To minimize immortal time bias, only those on therapy for over 3 months were included. Of 219 patients included in the landmark analysis, 52 received a reduced dose intensity of bevacizumab. The median relative dose intensity (RDTI) of bevacizumab was 75% (range 9.1–96.9%). There was no significant difference in progression-free survival (11.2 vs. 14.8 months, p = 0.5) or overall survival (20.4 vs. 26.8 months, p = 0.1) between those receiving 100% vs. reduced RDTI. Exploratory analysis showed that even doses under 75% had no survival impact. Treatment-related grade 3/4 adverse events occurred more frequently with RDTI (30.7% vs. 15.5%). Reduced bevacizumab doses do not impact survival
Defining the integrated neighbourhood model: a systematic review of key domains and framework development
No full textBackground:
Health systems are increasingly adopting Integrated Neighbourhoods (INs) to deliver hyper-local, community-based care that integrates health, social care, and public sector resources to address healthcare costs, improve outcomes, and reduce health inequalities. However, IN models lack a unified definition and standard framework for development and evaluation, limiting their scalability and effectiveness. This systematic review aims to establish a foundational framework for INs, identifying key domains to guide their implementation (including barriers of implementation, evaluation, and potential for future research.
Methods:
A systematic literature search, restricted to the English language, was performed to identify relevant studies with expert librarian support. Study quality was assessed with the Mixed-Methods Appraisal Tool (MMAT). A Braun and Clarke thematic analysis was conducted to identify recurring themes and extract key domains.
Results:
A total of 29 studies met the inclusion criteria, encompassing a diverse range of IN models with varying focus areas and methodologies. Seven key domains emerged as central to effective IN models: integrator host, integrator enablers, integrator partnership principles, core integrated workforce, core areas of work, and services provided. These domains support multidisciplinary collaboration, enhance resource utilisation, and promote community engagement. However, barriers such as funding limitations, digital exclusion, and inconsistent evaluation frameworks present challenges to IN scalability and sustainability.
Conclusion:
This proposed framework provides a starting point for a standardised structure for implementing and evaluating INs, guiding clinicians, academics, and policymakers in developing sustainable, equitable, and adaptable community-based care solutions with the potential to improve access to patients from low-socioeconomic and underserved communities.
Trial Registration:
PROSPERO ID: CRD42024597197; available: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=597197
Establishing cardiac MRI reference ranges stratified by sex and age for cardiovascular function during exercise
No full textPurpose: To evaluate the effects of exercise on left ventricular parameters using exercise cardiac MRI in healthy adults without known cardiovascular disease, and establish reference ranges stratified by age and sex.
Materials and Methods: This prospective study included healthy adult participants with no known cardiovascular disease or genetic variants associated with cardiomyopathy, enrolled between January 2018 and April 2021, who underwent exercise cardiac MRI evaluation. Participants were imaged at rest and after exercise, with parameters measured by two readers. Prediction intervals were calculated and compared across sex and age groups.
Results: The study included 161 participants (mean age, 49±[SD]14 years; 85 female). Compared with the resting state, exercise caused an increase in heart rate (64±9 bpm vs 133±19 bpm, P < 0.001), left ventricular end-diastolic volume (140±32 ml vs 148±35 ml, P < 0.001), stroke volume (82±18 ml vs 102±25 ml, P < 0.001), ejection fraction (59±6% vs 69±7%, P < 0.001), and cardiac output (5.2±1.1 l/min vs 13.5±3.9 l/min, P < 0.001), and a decrease in left ventricular end-systolic volume (58±18 ml vs 46±15 ml, P < 0.001). There were significant differences in exercise response between groups stratified by sex and age for most parameters.
Conclusion: In healthy adults, an increase in cardiac output after exercise is driven by a rise in heart rate with both increased ventricular filling and emptying. Normal ranges for exercise response, stratified by age and sex, are established as a reference for the use of exercise cardiac MRI in clinical practice
Radiation protection: safety measures and knowledge among interventional radiologists- a UK-based analysis of current practices and recommendations for improvement
No full text• Lack of Evidence-Based Practice: There is a significant gap in evidence-based practices related to radiation protection. Our understanding of global standards and practices, as well as their long-term impact on operator health, remains limited. Standardising current procedures and establishing a uniform database for data entry by all practitioners performing X-ray-based procedures would be beneficial.
• Lack of tailored measures to enhance protection for Female Operators: Female operators are at a greater risk of radiation exposure (Front Genet 10:260, 2019), underscoring the need for comprehensive guidance and standards to mitigate both short—and long-term health risks. Research and higher-level evidence are essential to evaluate the efficacy of current practices, along with better access to tools for accurate fetal dose calculation when needed.
• Balancing Protection and Ergonomics: It is crucial to achieve the right balance between adequate lead protection and ergonomic considerations for the spine and musculoskeletal system. The minimum level of lead protection scientifically required to ensure operator safety without compromising comfort and posture must be determined.
• Lack of accurate data regarding the log of health issues for personnel working with radiation gears. A national or international anonymised registry would be ideal for capturing and monitoring such data