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AI-powered intestinal ultrasound in inflammatory bowel disease: Advancing toward automated disease assessment
No full text: The management of inflammatory bowel disease (IBD) relies on accurate disease assessment and close monitoring to guide therapy and evaluate treatment response. While endoscopy remains the gold standard for detecting mucosal inflammation, its invasiveness and inability to fully assess transmural disease or extraintestinal complications limit its use as a stand-alone tool. Cross-sectional imaging modalities, such as CT and MRI, provide accurate evaluations but are hindered by high cost, limited accessibility, and patient burden. Therefore, intestinal ultrasound (IUS) has emerged as a safe, non-invasive, and reproducible modality to evaluate transmural inflammation and complications in real time, making it increasingly relevant for both Crohn's disease and ulcerative colitis. However, challenges such as operator dependence, variability in image acquisition, and lack of standardize protocols have limited its widespread adoption. Artificial intelligence (AI) offers transformative potential to overcome these barriers by automating image analysis, standardising interpretation, and reducing interobserver variability. Early applications have shown promise in bowel wall segmentation and thickness assessment, with future opportunities to further integrate imaging features with biomarkers, clinical data, and multi-omics for precision medicine. This review aims to explore the current and future roles of IUS, summarizing the potential of AI in IUS to improve diagnostic accuracy, enhance disease monitoring, and enable personalized patient management. We will discuss the strengths and limitations of existing approaches, highlight barriers to clinical implementation, and outline perspectives on how AI-enhanced IUS may transform both research and routine care in IBD
Arnold Toynbee, 300 Years of Anglo-Jewry (1956) https://www.academia.edu/146742185/Arnold_Toynbee_300_Years_of_Anglo_Jewry_1956_
No full textADDITIONS, INTEGRATIONS, CORRECTIONS AND SUPPLEMENTS TO THE BIBLIOGRAPHY OF ARNOLD JOSEPH TOYNBEE, No. 601, Addition to Part I, Works by Arnold J. Toynbe
Multi-Satellite Based Passive Localization of Spaceborne Cooperative RF Emitters: Simulation Framework and Impact of Constellation Geometry
No full textThis paper presents a simulation framework for space-based cooperative target localization using Time Difference of Arrival (TDOA) and Frequency Difference of Arrival (FDOA) measurements from Low Earth Orbit (LEO) satellite constellations. The study addresses how geometric constellation configurations affect the accuracy of passive Radio-Frequency (RF) tracking for cooperative spacecraft. The simulation methodology is described through its constituent functional blocks: scenario configuration establishing orbital parameters and RF system specifications, orbit propagation, Signal-to-Noise Ratio (SNR) evaluation, detectability analysis with Line-of-Sight (LOS) verification, synthetic measurement generation, and a robust three-stage position and velocity estimation. This estimation algorithm integrates multi-start initialization to ensure probabilistic coverage of the global minimum, Trust-Region-Reflective (TRR) optimization with analytical Jacobians for computational efficiency, and final validation to reject impossible solutions. The framework is validated through three case studies employing four-satellite cluster architectures at 850-950 km altitude, tracking a cooperative target in Sun-Synchronous orbit at 550 km: a configuration combining co-orbital and cross-track sensors, a purely co-orbital arrangement, and a cross-track configuration with symmetric geometry. Results demonstrate that constellation geometry, quantified by the Geometric Dilution of Precision (GDOP), is the dominant factor determining localization performance for a given target. For the assumed system parameters, the first and most favorable geometry configuration achieves mean position and velocity accuracy of 16.93 m and 0.80 m/s, respectively, when GDOP remains below 5, with progressively degrading performance at higher GDOP values. Conversely, the co-orbital configuration produces GDOP values exceeding 300, yielding mean position and velocity errors above 16 km and 320 m/s, while the symmetric cross-track architecture exhibits bimodal error distributions with 46% of solutions converging to geometrically ambiguous positions displaced by approximately 90° in right ascension. These findings establish that spatial diversity in satellite distribution is essential for accurate TDOA-FDOA-based localization, providing design guidelines for constellation architectures supporting cooperative tracking in congested LEO environments
Extensive experimental investigation and phenomenological modelling of a DI ultra-lean hydrogen light-duty engine: combustion analysis, NOx and unburned fuel emissions
No full textThe vehicular sector is focused on reducing engine emissions in response to national and international regulations, targeting CO2 reduction. Carbon-neutral fuels, particularly green hydrogen from renewable sources, offer a promising path forward. In this perspective, this study investigates a 2.5-L 4-cylinder spark-ignition engine directly supplied with hydrogen, designed for the light-duty transport sector. An extensive experimental campaign explores the engine behaviour under various engine speeds and torque levels, working in ultra-lean conditions (relative air/fuel ratio − λ − between 2.15 and 3.30). Experiments evidenced that leaner mixtures and higher speeds lead to longer combustion durations in both early and main stages. They underlined that the combustion centre can assume an optimal timing under medium/low load operations and must be delayed at high loads to avoid knocking cycles. NOx emissions are globally reduced and become relevant only in the conditions where λ is close to 2 (maximum torque curve). The production of unburned hydrogen (uH2) is slightly dependent on the operating conditions and becomes significant only when the combustion is less stable (minimum load). The experimental results are used for an extensive validation of the predictive phenomenology-based combustion model, considering flame propagation enhancements related to turbulence and thermo-diffusive instabilities. Additionally, refined emission models are employed to estimate levels of uH2 and NOx. Simulation results are in good agreement with the experimental global engine parameters and combustion indicators, with average errors below 2 % and 1.6 CADs, respectively. Similarly, the pressure cycles and the related burn rates are correctly reproduced, and the influence on the model predictivity of the thermo-diffusive flame instabilities is evidenced. Finally, the model demonstrates to accurately follow the variations in NOx emission over the engine operating domain, while uH2 levels are adequately captured by the simulations, with higher discrepancies in the operating points with larger combustion cyclic variability
Exercise in pregnancy and maternal cardiovascular changes
No full textObjective: To evaluate whether regular aerobic exercise during pregnancy reduces the risk of hypertensive disorders of pregnancy and improves maternal cardiovascular adaptation. Methods: This was a secondary analysis of a randomized clinical trial including women with singleton gestation randomly assigned in a 1:1 ratio to an exercise group or a control group. The intervention consisted of a structured aerobic exercise program from the first trimester until 35 weeks. Echocardiographic examinations were offered between 37 and 38 weeks. The primary endpoint was the incidence of gestational hypertension. Secondary outcomes included preeclampsia and echocardiographic hemodynamic, geometric and mitral inflow indices. Results: Among 938 randomized participants, 54 underwent echocardiography. The incidence of gestational hypertension was lower in the exercise group compared with the control group (10.1% vs 15.1%; RR 0.56, 95% CI 0.33–0.97). Preeclampsia incidence was 2.5% and 3.5%, respectively (RR 0.71, 95% CI 0.23–2.21). In the echocardiography subgroup, exercise participants had lower systolic and diastolic blood pressure, higher stroke volume (79.7 ± 7.3 vs 74.5 ± 9.2; p = 0.02), and more favorable mitral inflow indices, including a higher E’/A’ ratio (1.29 ± 0.17 vs. 1.15 ± 0.23; p = 0.01) and reduced impaired diastolic relaxation (0% vs. 27.3%; p < 0.01). Conclusion: Regular exercise during pregnancy is associated with lower risk of gestational hypertension and improved cardiovascular adaptation, supporting its role in maternal hemodynamic health. Trial registration: Clinicaltrials.gov NCT06355375 (Registration Date 20240409)
Technical review by the ESPGHAN Special Interest Group on Gut Microbiota and Modifications on the health outcomes of infant formula supplemented with prebiotics
No full text: Prebiotics are defined as substrates that are selectively utilized by host microorganisms, conferring health benefits. This technical review focusing on prebiotic-supplemented infant formulas is one of the five manuscripts developed by the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition Special Interest Group on Gut Microbiota and Modifications (SIG-GMM). The SIG-GMM conducted a technical review to evaluate the clinical outcomes of prebiotic-supplemented infant formulas in healthy infants (0-12 months) that were published before 2024. The review focused on the following clinical outcomes: anthropometric measurements, stool frequency and consistency, gastrointestinal symptoms, allergy prevention, infection prevention, and safety/tolerability. Following the review, all 20 SIG members anonymously voted on each statement, scoring them from 0 to 9. A score ≥6 indicated agreement with a statement. A statement was rejected if ≥75% of the members voted <6. Fifty-one publications were included, focusing on prebiotics such as short-chain galacto-oligosaccharides, long-chain fructo-oligosaccharides, acidic oligosaccharides, and polydextrose/galacto-oligosaccharides. This technical review demonstrates that prebiotic-supplemented formulas are well tolerated, with no significant differences in anthropometric parameters compared to those fed non-supplemented formula. Prebiotic supplementation decreased stool consistency and increased stool frequency depending on the dosage and type. This technical review provides information on prebiotic-supplemented infant formulas in healthy infants. Overall, no significant clinical health benefits were observed in terms of infections and antibiotic use, colic, and allergy
Long-Term Outcomes of Secukinumab in Moderate-to-Severe Hidradenitis Suppurativa: A Multicentre Cohort Study
No full textBackground: Hidradenitis suppurativa (HS) is a chronic and debilitating skin disorder. Secukinumab, a biologic agent targeting interleukin-17, is a new therapeutic option for HS. However, data regarding its long-term outcomes are scarce. Objective: To evaluate the long-term effectiveness, safety, and predictors of response to secukinumab in a real-world cohort of patients with moderate-to-severe HS. Methods: Multicentre retrospective cohort study across 12 Italian tertiary referral hospitals. The primary effectiveness outcomes were the proportion of patients achieving Hidradenitis Suppurativa Clinical Response (HiSCR) and a 55% reduction in the International Hidradenitis Suppurativa Severity Score System (IHS4-55) at any time point. Results: A total of 77 patients (53% female; median age 38 years, interquartile range: 27-50) met the inclusion criteria. At week 52, 36.2% of patients achieved HiSCR and 55.6% achieved IHS4-55. The mean reduction from baseline to week 52 was 50.8% for skin pain Numeric Rating Scale and 55.2% for Dermatology Life Quality Index. Agreement between IHS4-55 and HiSCR was 76.6% (Cohen's kappa 0.5255; 95% CI: 0.4307-0.6202, P < .0001). Patients in Hurley stage 3 had a significantly lower hazard ratio (HR) of achieving IHS4-55 than those in Hurley stage 2 (HR 0.52; 95% CI: 0.31-0.89, P = .017), which persisted in the multivariable model (HR 0.56; 95% CI: 0.31-0.99, P = .044). No new safety concerns were identified. Conclusions: This study suggests that secukinumab provides clinically meaningful long-term outcomes in HS management, even in bio-experienced patients
Experimental investigation into the roll damping characteristics of the intact and damaged ship in still water and ice floes
No full textShips face potential risks of damage from navigation environments and human factors. The multiphase flow of ship-water-ice particularly increases the difficulty of evaluating the roll damping characteristics of a damaged ship in ice floes. To better analyze effects brought by different factors, five test scenarios with initial heeling angle of 6.0, 13.0 and 21.0 deg are performed in this paper, including the intact ship and damaged ship in the still water and ice floes. Experimental results indicate that regardless of the intact ship or the damaged ship, effects of ice floes on the roll damping of the ship can be ignored. However, effects of flooding water and the ventilation level of the flooded compartments must be considered. Especially for the flooding water, the nonlinear damping coefficients of the damaged ship are increased by approximately one order of magnitude compared to the intact ship. In general, the test results can not only be used for the current qualitative analysis of roll damping but also serve as benchmarking data for future verification of numerical reliability
