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Article Microstructure-Based Prediction of Mechanical Properties of Austempered Ductile Iron Using Multiple Linear Regression Analysis(Springer Int Publ AG, 2025) Yalcin, M. Alp; Davut, KemalMultiple linear regression analysis (MLRA) was used to predict the mechanical properties of austempered ductile iron (ADI) including yield and tensile strength, uniform elongation, hardening exponent, as well as fracture energy by building a model that uses characteristic features of microstructural constituents as input parameters. The complex multi-scale microstructure of ADI, which is composed of spherical graphite particles over 10 mu m diameter; and an ausferritic matrix with sub-micron sized features, makes it ideal for prediction of mechanical properties. For that purpose, low alloyed ductile iron samples austempered between 300 and 400 degrees C for 45-180 min were tensile tested, and also multi-scale microstructural characterization were carried out using optical microscope, SEM, and EBSD technique. Moreover, a sensitivity analysis was performed to determine which microstructural parameter(s) each mechanical property is most sensitive to. The results show that tensile and yield strength are most sensitive to size and morphology of matrix phases. Moreover, the size and aspect ratio of acicular ferrite correlate well with those of high-carbon austenite; since both form during transformation of parent austenite into ausferrite during austempering treatment. Equiaxed parent austenite grains transform into ausferrite with acicular morphology during the austempering treatment; and presence of equiaxed austenite grains in the austempered samples indicates untransformed regions during austempering treatment. Ductility was found to be more sensitive to nodularity of graphite particles, and this sensitivity was attributed to the size difference between graphite particles and grain size of matrix phases.Article Utilizing POCUS in the Diagnosis of Small Bowel Obstruction and the Barriers to Its Implementation in Resource-Limited Settings: A Systematic Review(Springer Int Publ AG, 2026) Razakh, Ayesha; Uzor, Angelina; Htoon, April; Valko, MichalPurposeSmall bowel obstruction (SBO) is a common surgical emergency that can lead to significant morbidity, mortality, and healthcare costs, particularly when diagnosis is delayed. In rural and resource-limited emergency settings, advanced imaging techniques like computed tomography (CT) may not be readily available. As a result, clinicians often rely on physical examinations and plain radiographs which can be unreliable. Point-of-care ultrasound (POCUS) provides a rapid, radiation-free and cost-effective diagnostic alternative that can be performed directly at the bedside.MethodsWe conducted a systematic review of published literature evaluating the diagnostic accuracy and clinical utility of POCUS in identifying SBO on the following databases PubMed, Web of Science, Cochrane Library and Google Scholar databases from January 2000 to December 2024. Studies were screened and selected based on the inclusion and exclusion criteria adhering to PRISMA 2020 guidelines.ResultsThe sensitivity of POCUS for SBO ranged from 85.0 to 100%, while specificity ranged from 54.0 to 100%. Diagnostic accuracy remained high across a broad range of expertise overcoming operator dependence. Examination durations are approximately 10-11 min, which is markedly shorter than 45-min to 3-h by CT.ConclusionPOCUS presents as a practical, scalable and cost-saving tool for diagnosing SBO in rural emergency care, addressing significant gaps where CT is not available and also facilitates faster diagnosis by timely identification of specific features. Future efforts should focus on developing validated algorithms for resource-limited settings allowing immediate care management.
