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Enhanced disturbance mitigation in nonlinear time delay systems with applications to double boost converters in microgrid environments

Factors contributing to visual intrapartum cardiotocograph interpretation variation among healthcare professionals: An integrative review

The reliability of cardiotocographs as diagnostic tools for fetal well-being is hampered by interpretational variations among healthcare professionals, contributing to high rates of cesarean sections and instrumental deliveries. While adjunct technologies may be used to confirm cases of fetal distress, those in resource constrained areas continue to rely on visual cardiotocograph interpretation to come up with the diagnosis of fetal hypoxia. This study investigated the factors contributing to variations in the visual interpretation of intrapartum cardiotocograph among healthcare professionals in the absence of adjunctive technologies. In this integrative literature review, we conducted a literature search of the following electronic databases: EBScohost, PubMed, Web of Science, and Scopus. The following search terms and Boolean operators were used: (Intrapartum OR Labor OR Labour OR Childbirth OR Birth OR Delivery) AND (Cardiotocography OR CTG OR "Electronic Fetal Monitoring" OR EFM) AND (Interpretation OR Analysis) AND (Variations OR Differences) AND (“Healthcare Workers” OR Nurses OR “Medical Workers” OR “Healthcare Professionals” OR Midwives OR Obstetricians). After removal of duplicates, a total of 1481 articles and titles were screened, 60 full-text articles were examined to verify whether they addressed the scope of the literature review. Nine articles addressed the factors contributing to variations in the visual interpretation of intrapartum cardiotocographs among healthcare professionals. The quality of the studies was appraised using the Quality Appraisal Tool for Studies of Diagnostic Reliability. Thematic analysis identified the following themes: 1) Interpretational variations in cardiotocograph characteristics among health professionals, and 2) factors leading to increased interpretational variation among healthcare professionals. Our results highlight the need for increased cardiotocograph training to improve consistency among health professionals, especially for suspicious and pathological traces, which often lead to cesarean section.

Optimising deep learning models for ophthalmological disorder classification

Abstract Fundus imaging, a technique for recording retinal structural components and anomalies, is essential for observing and identifying ophthalmological diseases. Disorders such as hypertension, glaucoma, and diabetic retinopathy are indicated by structural alterations in the optic disc, blood vessels, fovea, and macula. Patients frequently deal with various ophthalmological conditions in either one or both eyes. In this article, we have used different deep learning models for the categorisation of ophthalmological disorders into multiple classes and multiple labels utilising transfer learning-based convolutional neural network (CNN) methods. The Ocular Disease Intelligent Recognition (ODIR) database is used for experiments, and it contains fundus images of the patient’s left and right eyes. We compared the performance of two different optimisers, Stochastic Gradient Descent (SGD) and Adam, separately. The best result was achieved using the MobileNet model with the Adam optimiser, yielding a testing accuracy of 89.64%.

A systematic in vitro study of the effect of normoglycaemic and hyperglycaemic conditions on the biochemical and cellular interactions of clinically-available wound dressings with different physicochemical properties

Diabetic foot, leg ulcers and decubitus ulcers affect millions of individuals worldwide leading to poor quality of life, pain and in several cases to limb amputations. Despite the global dimension of this clinical problem, limited progress has been made in developing more efficacious wound dressings, the design of which currently focusses on wound protection and control of its exudate volume. The present in vitro study systematically analysed seven types of clinically-available wound dressings made of different biomaterial composition and engineering. Their physicochemical properties were analysed by infrared spectroscopy, swelling and evaporation tests and variable pressure scanning electron microscopy. These properties were linked to the interactions with inflammatory cells in simulated normoglycaemic and hyperglycaemic conditions. It was observed that the swelling behaviour and evaporation prevention at different glucose levels depended more on the engineering of the fibres than on the hydrophilicity and hydrophobicity of their biomaterials. Likewise, the data show that the engineering of the dressings as either non-woven or woven or knitted fibres seems to determine the swelling behaviour and interactions with inflammatory cells more than their polymer composition. Dressings presenting absorbent layers made of synthetic, non-woven fibres supported the adhesion of monocytes macrophages and stimulate the release of factors known to play a role in the chronic inflammation. Non-woven absorbent layers based on carboxymethyl cellulose mainly stimulating the iNOS, an enzyme producing free radicals; in the case of Kerracel this was combined with a swelling of fibres preventing the penetration of cells. Kaltostat, an alginate-based wound dressing, showed the higher level of swelling and supporte the adhesion of inflammatory cells with limited activation. Knitted dressings showed a limited adhesion of inflammatory cells. In conclusion, this work offers insights about the interactions of these wound dressings with inflammatory cells upon exudate changes thus providing further criteria of choice to clinicians.

Mechanism and CO2 emissions analysis of multi-solid-waste synergistic red mud-based composite cementitious materials under orthogonal tests

The type of diet consumed during prepuberty modulates plasma cholesterol, hepatic LXRα expression, and DNA methylation and hydroxymethylation during adulthood in male rats

Childhood obesity increases the risk of developing metabolic diseases in adulthood, since environmental stimuli during critical windows of development can impact on adult metabolic health. Studies demonstrating the effect of prepubertal diet on adult metabolic disease risk are still limited. We hypothesized that a prepubertal control diet (CD) protects the adult metabolic phenotype from diet-induced obesity (DIO), while a high-fat diet (HFD) would predispose to adult metabolic alterations. Sprague-Dawley male rats were fed either a CD or a HFD during the prepubertal period (day 30–40 of age) and subsequently a chronic HFD or CD, respectively, until adulthood (day 220 of age). As controls, rats aged 30 days were exclusively fed a CD or a HFD until adulthood. Body weight and composition, metabolic rate, biochemical and hormonal plasma measurements, hepatic gene expression and methylation and hydroxymethylation levels were analyzed at ages 30, 40 and 220 days. The prepubertal CD prevented fat mass accumulation, lean mass loss and metabolic inflexibility, showed lower insulin, leptin and cholesterol concentrations in adulthood despite the chronic HFD. Notably, the prepubertal CD led to higher hepatic Lxrα expression, lower hepatic global DNA methylation and higher hydroxymethylation in adulthood despite a chronic HFD. Conversely, a prepubertal HFD decreased adult metabolic flexibility, increased serum cholesterol, and decreased Lxrα expression and global DNA hydroxymethylation, while also increasing DNA methylation levels despite a chronic CD. In summary, a prepubertal CD protected the adult metabolic phenotype from high cholesterol concentrations associated with increased hepatic Lxrα expression and lower hepatic global DNA methylation in adulthood, despite exposure to a chronic HFD. Conversely, a prepubertal HFD altered the adult metabolic phenotype.

Experimental study on modal analysis and vibration response of tunnel structures under different damage conditions due to subway train loads

Correction: Unveiling the obstacles encountered by women doctors in the Pakistani healthcare system: A qualitative investigation

Author Correction: MT1G promotes iron autophagy and inhibits the function of gastric cancer cell lines by intervening in GPX4/SQSTM1

Correction: Human-Prosthetic Interaction (HumanIT): A study protocol for a clinical trial evaluating brain neuroplasticity and functional performance after lower limb loss

Effects of perfluorolauric acid exposure on intestinal microbial community and physiological health indicators in mice

Magnetic resonance angiography in diagnostic long-term follow-up of primary patency of the MOTIV drug-eluting bioresorbable vascular scaffold in the region below the knee: 5 years of experience

Purpose Treatment of peripheral artery disease (PAD) in the region below the knee (BTK) is dissatisfying as failure of treated target lesions (TLF) is frequent and diagnostic imaging is often challenging. In the BTK-region metallic drug-eluting stents (mDES) yielded best results concerning primary patency (PP), but also annihilate signal in magnetic resonance angiography (MR-A). A recently introduced non-metallic drug eluting bioresorbable Tyrocore® vascular scaffold (deBVS), that offers an option for re-treatment of lesions due to its full degradation within 3–4 years after placement, was investigated with respect to its compatibility with MR-A to unimpededly depict previously treated target lesions. Methods Patency of the deBVS in the BTK-region was assessed retrospectively using contrast enhanced MR-A of the lower limbs in patients with PAD of Lafontaine-grades II-IV (n = 19). Clinically driven MR-A censoring was triggered by an assumed target lesion failure (CD-TLF), which served to compute the probability of PP during the observation period of 5 years. Compatibility of this particular deBVS with MRI was additionally proven via in-vitro experiments. Results The scaffold was found to be fully compatible with MRI. The normalised intra-luminal signal measured in MR-A increased significantly after successful deBVS-placement. The retrospective 5-years PP-probability was 0.87 (CI95%: [0.71,1.0]) with 2 stent-occlusions observed after 90 days. No major adverse events occurred. Conclusion Assessment of PAD in the BTK-region after placement of the Tyrocore®-deBVS using MRA is feasible. The promising high PP-probability after 5-years and the persistent full interpretability of treated target lesions by MR-A after stent-placement encourage further prospective assessment of this deBVS in treatment of PAD in the BTK-region.

CFD analysis of heat transfer enhancement in impinging jet array by varying number of jets and spacing

Investigating the moments of “aha” and “hmm” through acoustic analysis of voice and speech in pre-service physics teacher education–A novel method for identifying significant learning moments

The aim of the study was to find whether certain meaningful moments in the learning process are noticeable through features of voice and how acoustic voice analyses can be utilized in learning research. The material consisted of recordings of nine university students as they were completing tasks concerning direct electric circuits as part of their course of teacher education in physics. Prosodic features of voice—fundamental frequency (F0), sound pressure level (SPL), acoustic voice quality measured by LTAS, and pausing—were investigated. The results showed that instances of confusion and understanding were manifested in acoustic parameters. F0 was significant in characterizing the both kind of learning instances. Confusion had lower SPL and alpha ratio, indicating that voice quality was softer than in understanding. Degree of voice pauses was lower in understanding, suggesting less hesitation or need for clarification for understanding compared to confusion. Voice research adds to the research of learning as speaker´s voice is affected by the different instances in the process of learning. This research approach can be used for identification of important instances of learning and directing these instances to closer analysis of content or interaction to further understand the learning processes. Therefore, this study is a novel contribution to the study of learning as it adds acoustic voice and speech analyses to the discipline.

Adaptive neural observer-based output feedback anti-actuator fault control of a nonlinear electro-hydraulic system with full state constraints

Assessing cardiovascular disease risk and social determinants of health: A comparative analysis of five risk estimation instruments using data from the Eastern Caribbean Health Outcomes Research Network

Background Accurate assessment of cardiovascular disease (CVD) risk is crucial for effective prevention and resource allocation. However, few CVD risk estimation tools consider social determinants of health (SDoH), despite their known impact on CVD risk. We aimed to estimate 10-year CVD risk in the Eastern Caribbean Health Outcomes Research Network Cohort Study (ECS) across multiple risk estimation instruments and assess the association between SDoH and CVD risk. Methods Five widely used CVD risk estimation tools (Framingham and WHO laboratory, both laboratory and non-laboratory-based, and ASCVD) were applied using data from ECS participants aged 40–74 without a history of CVD. SDoH variables included educational attainment, occupational status, household food security, and perceived social status. Multivariable logistic regression models were used to compare differences in the association between selected SDoH and high CVD risk according to the five instruments. Findings Among 1,777 adult participants, estimated 10-year CVD risk varied substantially across tools. Framingham non-lab and ASCVD demonstrated strong agreement in categorizing participants as high risk. Framingham non-lab categorized the greatest percentage as high risk, followed by Framingham lab, ASCVD, WHO lab, and WHO non-lab. Fifteen times more people were classified as high risk by Framingham non-lab compared with WHO non-lab (31% vs 2%). Mean estimated 10-year risk in the sample was over 2.5 times higher using Framingham non-lab vs WHO non-lab (17.3% vs 6.6%). We found associations between food insecurity, those with the lowest level compared to the highest level of education, and non-professional occupation and increased estimated CVD risk. Interpretation Our findings highlight significant discrepancies in CVD risk estimation across tools and underscore the potential impact of incorporating SDoH into risk assessment. Further research is needed to validate and refine existing risk tools, particularly in ethnically diverse populations and resource-constrained settings, and to develop race- and ethnicity-free risk estimation models that consider SDoH.

Atherogenic index of plasma and cardiovascular outcomes in female patients undergoing percutaneous coronary intervention: insights from a retrospective cohort study

Prevalence of accessory navicular in Japanese children: A cross-sectional study using ultrasound–Katsuragi Integrated Defense for Locomotive Syndrome in children study

The accessory navicular (AN) is an accessory bone located on the posteromedial aspect of the navicular tuberosity that can cause pain following overuse or trauma, particularly during childhood. However, the detailed epidemiological characteristics of AN in children have not been well studied. This study aimed to clarify the prevalence of AN and painful AN among Japanese children by examining the characteristics according to sex and age. This cross-sectional study used data from the Katsuragi Integrated Defense for Locomotive Syndrome in Children Study, focusing on musculoskeletal disorders in 875 children aged 6–15 years, with 1750 feet being assessed. Children were divided into five age groups: 6–7, 8–9, 10–11, 12–13, and 14–15. AN was detected using ultrasound to avoid radiation exposure. The sex- and age-group-dependent prevalence of AN and painful AN were calculated, and statistical analyses examined sex differences in prevalence by age group. The overall prevalence of AN was 15.1%, higher in females (17.9%) than in males (12.3%). The prevalence of AN increased with age in both sexes. Among cases diagnosed with AN, 20.8% were symptomatic, with a unimodal peak observed at ages 12–13 in males and 10–11 in females. No statistically significant differences were observed in the proportion of painful AN between sexes. This is the first large-scale epidemiological study on AN in children. The overall prevalence of AN was 15.1%, higher in females than in males. Additionally, 20.8% of patients with AN experienced pain. The results of this study provide important epidemiological data to support clinical management strategies for pediatric patients with AN.

SOFCs integrated with SMES under dynamic power control using Chernobyl disaster optimizer

Abstract The current study uses the Chernobyl disaster optimizer (CDO), a new metaheuristic optimizer, to identify the seven unknown parameters of solid oxide fuel cells (SOFCs). The procedures of the CDO is based on physical behavior of the elaborated radiations from the well-known Chernobyl disaster according to their mass, speed, frequency, and degree of ionization. The sum of square errors (SMSE) among the estimated and the real measured output voltage datasets of SOFCs is minimized employing the CDO. Set of boundaries of the SOFC’s process is taken into consideration with the problem formulation. SOFCs stack’s model is examined at 800οC and 900οC and its performance is confirmed. The CDO extracts more precise SOFCs’ parameters compared to other competitors. The CDO’s convergence patterns and the SOFCs unit’s performance are studied and proved at steady-state by comparing its results to a number of recognized algorithms under varied operating scenarios. A significant SMSE’s values of 3.46 µV2 and 7.38 µV2 are attained at 800οC and 900οC, respectively by the CDO. As a result, the polarization principal curves of the measured and estimated voltage datasets are checked and verified with very close matching. The dynamic behavior of the SOFCs stack is examined in relation to direct load, electric networks, and superconducting magnetic energy storage devices (SMES) for additional validation and illustration. The role of the SOFCs stack in controlling the active and reactive power delivered to the network and direct load is investigated using two controllers: one to control the inverter, which converts the SOFC’s dc output to the main network, and the other to control the SMES. The Simulink/MATLAB environment is used to indicate the validity of the proposed framework under both steady-state and dynamical conditions. The comprehensive assessments show that the CDO capabilities are very effective when used with microgrids.

Transitions in intensive care: Investigating critical slowing down post extubation

Complex biological systems undergo sudden transitions in their state, which are often preceded by a critical slowing down of dynamics. This results in longer recovery times as systems approach transitions, quantified as an increase in measures such as the autocorrelation and variance. In this study, we analysed paediatric patients in intensive care for whom mechanical ventilation was discontinued through removal of the endotracheal tube (extubation). Some patients failed extubation, and required a re-intubation within 48 hours. We investigated whether critical slowing down could be observed post failed extubations, prior to re-intubation. We tested for significant increases (p <.05) between extubation and re-intubation, in the variance and autocorrelation, over the time series data of heart rate, respiratory rate and mean blood pressure. The autocorrelation of the heart rate showed a significantly higher proportion of increases in the group that failed extubation, compared who those who did not. It also showed a significantly higher magnitude of increase for the failed extubation group in a t-test. Moreover, incorporating these magnitudes significantly improved the fit of a logistic regression model when compared to a model that solely used the mean and standard deviation of the vital signs. While immediate clinical utility is limited, the work marks an important first step towards using dynamical systems theory to understand the dynamics of signals measured at the bedside during intensive care.