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Improved Design-Oriented Analytical Model for Switched Reluctance Machines' Unsaturated Inductance in Non-Overlap Conditions
No full textDesign-oriented analytical modelling of switched reluctance machines (SRMs) is currently an active field of research, as it significantly alleviates the computational burden of design processes by replacing or complementing finite element analysis. The modelling of saturated SRMs, including the determination of saturated flux loci and the calculation of torque and current waveforms, requires prior knowledge of the unsaturated inductance vs rotor position profile. This work proposes an improved analytical model to determine unsaturated inductances in non-overlap conditions, based on a twofold improvement of the permeance method: the use of elliptic flux tubes; and the ability to self-tailor the flux tube shapes to any machine geometry. Its accuracy is proven against finite element analysis applied to four designs and against experimental results of a full-scale prototype. Finally, it is shown how the model can be incorporated into a fully analytical design tool, whose accuracy in calculating performance and computational burden are evaluated
Two-Year Outcomes after Selective Early Treatment of Patent Ductus Arteriosus with Ibuprofen in Preterm Babies. Follow-Up of Baby-OSCAR - A Randomised Controlled Trial
Get PDFBackgroundChildren born extremely preterm are at increased risk of developmental problems and respiratory morbidity due to patent ductus arteriosus (PDA). The objective of this study was to evaluate whether early treatment of a PDA ≥1.5 mm with ibuprofen improved neurodevelopmental and respiratory outcomes at 24 months of age, corrected for prematurity.MethodsBaby-OSCAR was a UK multi-center placebo-controlled masked randomized clinical trial in infants born 23+0–28+6 weeks' gestation. The main long-term outcome was survival without moderate or severe neurodevelopmental impairment at 24 months’ corrected age, assessed using parent report primarily or classified by blinded end-point review committee where parent-reported data were not available. Other secondary outcomes included survival without respiratory morbidity and duration of oxygen supplementation. (ISRCTN Registry number ISRCTN84264977).FindingsFrom July 2015 through December 2020, 653 infants underwent randomization. At 24 months’ corrected age, outcome data were available for 537 children: 263 in the ibuprofen group and 274 in the placebo group. Survival without moderate to severe neurodevelopmental impairment in the ibuprofen and placebo groups was 131/248 (53.0%) and 134/259 (51.9%) respectively; adjusted risk ratio 1.01 (95% confidence interval [CI] 0.86–1.18); p = 0.901. Survival without respiratory morbidity was 66/220 (30%) and 74/225 (32.9%) respectively; adjusted risk ratio 0.89 (95% CI 0.68–1.18). Median duration of oxygen supplementation from randomization was 76.0 and 78.0 days, respectively; adjusted median difference −1.5 (−13.8 to 10.9).InterpretationWe found no evidence of an improvement in neurodevelopmental and respiratory outcomes at 24 months’ corrected age, after selective early treatment of a PDA ≥1.5 mm with ibuprofen in children born extremely preterm
The Experiences of Endometriosis Patients During Primary Healthcare Encounters: A Systematic Review of Qualitative Evidence
Get PDFEndometriosis affects 10% of those assigned-female-at-birth worldwide. Diagnosis typically takes between 5–12 years. This qualitative systematic review explored endometriosis patients’ experiences with primary healthcare professionals from presentation before diagnosis to post-diagnosis follow-up. Six electronic databases were searched: CINAHL, MEDLINE, Embase, PubMed, Scopus, and PsycINFO. A total of 37 articles were included and synthesized thematically. Findings showed common issues that patients were experiencing during their interactions with primary healthcare professionals, including dismissal regarding their symptoms, delayed referral to secondary care, and lack of knowledge regarding endometriosis. This review highlights a need for improved education and awareness surrounding endometriosis amongst primary healthcare professionals
Long-Term Forecasting of Long-Lived Oceanic Eddies Using an Improved Informer Framework
Get PDFLong-term prediction of long-lived mesoscale oceanic eddies plays a crucial role in ocean dynamics research, as its accuracy impacts climate change assessments, ocean energy transport analysis, and marine resource management. However, due to the nonlinear, multi-scale nature of vortex dynamics, it remains challenging. To address this, we propose an Informer-based deep learning framework enhanced with two key innovations: (1) an adaptive feature selection module that dynamically prioritizes input features to improve prediction robustness, and (2) a geospatial loss function based on the Haversine formula to optimize spatial accuracy. In addition, we investigates the unique influence of dipole eddies on trajectory predictability and analyzes how different eddy lifecycle stages affect prediction performance, offering theoretical and empirical insights into these complex patterns. Experiments show that our method outperforms seven baseline models across multiple metrics, achieving a mean geodesic distance of 13.624 km in the representative 30-day input and 15-day prediction setting and reducing error accumulation in long-term forecasts. Specifically, our work focuses on eddies with lifespans exceeding one year, providing dedicated predictive tools tailored for these long-lived ocean phenomena. These advances provide a foundation for future integration of physical constraints and environmental variables, promising enhanced predictive tools for ocean dynamics research
ESPEN Guideline on clinical nutrition in surgery -Update 2025
No full textEarly oral feeding is the preferred mode of nutrition for surgical patients. Avoidance of any nutritional therapy bears the risk of underfeeding during the postoperative course after major surgery. Considering that malnutrition and underfeeding are risk factors for postoperative complications, nutritional therapy is mandatory for any surgical patient at nutritional risk, especially for those undergoing upper gastrointestinal surgery. The focus of this guideline is to cover nutritional aspects of the Enhanced Recovery After Surgery (ERAS) concept and the special nutritional needs of patients undergoing major surgery, e.g. for cancer, and of those developing severe complications despite best perioperative care. From a metabolic and nutritional point of view, the key aspects of perioperative care include: a) Integration of nutrition into the overall management of the patient, b) avoidance of long periods of preoperative fasting c) re-establishment of oral feeding as early as possible after surgery d) start of nutritional therapy early, as soon as a nutritional risk becomes apparent e) metabolic control e.g. of blood glucose, f) reduction of factors which exacerbate stress-related catabolism or impair gastrointestinal function, g) minimized time on paralytic agents in the postoperative period, and h) early mobilization to facilitate protein synthesis and muscle function.The guideline presents 44 recommendations for clinical practice in patients undergoing elective and non-elective surgery, including new recommendations for frailty assessment, sarcopenia diagnosis, and prehabilitation. As in the former ESPEN practical guideline, the recommendations were additonally presented in decision-making flowcharts
Detection of early-stage hepatocellular carcinoma: a retrospective evaluation of ultrasonography surveillance and surveillance adherence
Get PDFBackground: Hepatocellular carcinoma (HCC) surveillance using 6-monthly ultrasonography (US) intervals is recommended. This study investigated the factors associated with early-stage HCC detection.Methods: All patients with a new HCC diagnosis for the first time between 2019 and 2022 were included. All pre-treatment imaging was independently reviewed according to Liver Imaging Reporting and Data System (LI-RADS) criteria. Early-stage HCC was defined as a single tumour <50 mm or up to 3 tumours all <30 mm. Rate of adherence was expressed as the proportion of the number of 6-monthly surveillance US performed relative to the total number of surveillance US the patient should have undergone over the preceding 5 years or since the diagnosis of cirrhosis, if it was within the preceding 5 years.Results: The study cohort included 175 patients with new HCC. The median age at diagnosis was 71 years; 78% were males; median body mass index (BMI) was 29.3 kg/m2; 94% were of European ancestry and the most common aetiology was metabolic dysfunction-associated steatotic liver disease (MASLD) (58%). One third (37%) presented through primary surveillance (surveillance group) and the remainder were found to have HCC when investigated for other indications (incidental group). Only the age at presentation [P=0.003; odds ratio (OR) 0.937, 95% confidence interval (CI): 0.899–0.978] and being on HCC surveillance (P<0.001; OR 5.867, 95% CI: 2.533–13.586), but not surveillance adherence were independently associated with early-stage HCC detection.Conclusions: Being part of primary surveillance, irrespective of adherence rate, is associated with early stage HCC detection. As many patients as possible should be enrolled into primary surveillance programme, even if adherence to recommended frequency is not followed rigorously
Inequalities in hormone replacement therapy prescribing in UK primary care: population based cohort study
Get PDFObjective To quantify prescribing of hormone replacement therapy (HRT) in women aged 40-60 years by type of HRT and length of use, and to determine sociodemographic factors associated with receiving a HRT prescription.Design Population based cohort study.Setting QResearch database of primary care practices in England, 1 January 2013 to 13 July 2023, and patient electronic health records for prescribing information .Participants 1 978 348 women aged 40-60 years at any time over a 10 year period.Main outcome measures Overall uptake of two or more prescriptions of the same type of HRT in women of menopausal age, length of use, and association between ethnic group, deprivation, and geographical region and receiving a HRT prescription before and during the eight years since implementation of National Institute for Health and Care Excellence (NICE) guidance on the menopause in 2015 in the UK.Results The cohort comprised 1 978 348 women with a mean age of 49.4 years, and 76.2% were white women. Overall, 379 911 (19.2%) women received two or more HRT prescriptions. Combination HRT formulations in one prescription were the most frequently prescribed (62.4% of those prescribed HRT), with 43.3% receiving oral and 26.3% transdermal formulations. Mean age at first prescription was 49.8 years. Rates for two or more prescriptions of HRT were higher in white women (22.6%) than in other ethnic groups, ranging from 8.9% in Caribbean women to 3.9% in black African women. Prescription rates decreased with increasing social deprivation, from 24.2% in the most affluent to 10.9% in the most deprived groups. London had lower prescription rates (11.7%) than other regions (all >19%). Multivariable Cox regression showed that non-white ethnic groups had significantly lower HRT prescription rates (hazard ratios 0.85-0.92, P<0.001), and each increase in social deprivation group was associated with lower HRT prescription rates (hazard ratio for the most deprived group 0.92, 95% confidence interval 0.92 to 0.93, P<0.001).Conclusions This study identified differences in HRT prescribing in England based on ethnic group, socioeconomic status, and geographical location. White women and those in more affluent neighbourhoods were more likely to receive HRT than non-white women and those in more deprived areas. These findings suggest potential inequities that require further exploration
Remaining useful life prediction of lithium-ion batteries by leveraging end-of-charge characteristics
Get PDFPredicting the Remaining Useful Life (RUL) of lithium-ion batteries (LIBs) is crucial for ensuring their reliable performance and extending their lifespan, especially in applications such as electric vehicles (EVs). Traditional RUL prediction methods mainly focus on battery capacity degradation, but obtaining accurate capacity data in real-world settings is often challenging, leading to limited prediction accuracy. To address this issue, our study experimentally investigates the degradation behavior of EV LIBs by analysing variations in Constant-Current (C[sbnd]C) and Constant-Voltage (C[sbnd]V) charging durations at different stages of battery ageing. The results show significant changes in the rate of current decrease during the C[sbnd]V charging stage and the increase in Open Circuit Voltage (OCV) during the C[sbnd]C charging stage, resulting in varied charging times across degradation stages. Given the challenges posed by partial charging and uncertain degradation rates in practical scenarios, we propose a novel RUL prediction method. This method utilizes the C[sbnd]V charging characteristic, which is less affected by partial charging, and integrates Bayesian theory with real-time monitoring data to dynamically update model parameters, enhancing prediction accuracy. Our approach offers a practical, data-driven solution for more reliable LIB RUL prediction, providing a new tool for battery health management in EV applications
Acai Berry Extracts Can Mitigate the L-Glutamate-Induced Neurotoxicity Mediated by N-Methyl-D-Aspartate Receptors
Get PDFBackground/Objectives: Stroke is the second leading cause of death worldwide. There is an unmet need to manage stroke pathophysiology, including L-glutamate (L-Glu)-mediated neurotoxicity. The acai berry (Euterpe sp.) contains phytochemicals with potentially nutraceutical content. The aim of this study was to assess the ability of acai berry extracts to counter L-Glu neurotoxicity using human differentiated TE671 cells. Methods: The cytotoxicity of L-Glu and acai berry extracts was quantified using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. Mitochondrial function was examined by a quantitation of cellular ATP levels, the maintenance of the mitochondrial membrane potential (MMP), and the production of reactive oxygen species (ROS). Whole-cell patch-clamp recordings monitored the activation of N-methyl-D-aspartate receptors (NMDARs). Candidate phytochemicals from acai berry extracts were modeled in silico for NMDAR binding. Results: L-Glu significantly reduced cell viability, ATP levels, the MMP, and increased cellular ROS. Generally, acai berry extracts alone were not cytotoxic, although high concentrations were detrimental to ATP production, maintenance of the MMP, and elevated ROS levels. Whole-cell patch-clamp recordings revealed that the combined addition of 300 µM L-Glu and 10 µM glycine activated currents in differentiated TE671 cells, consistent with triggering NMDAR activity. Acai berry extracts ameliorated the L-Glu-induced cytotoxicity, mitochondrial dysfunction, elevated ROS levels, and limited the NMDAR-mediated excitotoxicity (p < 0.001–0.0001). Several virtual ligands from acai berry extracts exhibited high-affinity NMDAR binding (arginine, 2,5-dihydroxybenzoic acid, threonine, protocatechuic acid, and histidine) as possible candidate receptor antagonists. Conclusions: Acai berry phytochemicals could be exploited to reduce the L-Glu-induced neurotoxicity often observed in stroke and other neurodegenerative diseases
Exponential convergence of hp-ILGFEM for semilinear elliptic boundary value problems with monomial reaction
Get PDFWe study the fully explicit numerical approximation of a semilinear elliptic boundary value model problem, which features a monomial reaction and analytic forcing, in a bounded polygon Ω ⊂ R2 with a finite number of straight edges. In particular, we analyze the convergence of hp-type iterative linearized Galerkin (hp-ILG) solvers. Our convergence analysis is carried out for conforming hp-finite element (FE) Galerkin discretizations on sequences of regular, simplicial partitions of Ω, with geometric corner refinement, with polynomial degrees increasing in sync with the geometric mesh refinement towards the corners of Ω. For a sequence of discrete solutions generated by the ILG solver, with a stopping criterion that is consistent with the exponential convergence of the exact hp-FE Galerkin solution, we prove exponential convergence in H1(Ω) to the unique weak solution of the boundary value problem. Numerical experiments illustrate the exponential convergence of the numerical approximations obtained from the proposed scheme in terms of the number of degrees of freedom as well as of the computational complexity involved
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