检索结果-南通市图书馆

Machine learning-based decision tool for selecting patients with idiopathic acute pancreatitis for endosonography to exclude a biliary aetiology

引用

世界胃肠病学杂志:英文版 2023年第35期29卷 5138-5153页

作者： Simon Sirtl Michal Żorniak Eric Hohmann Georg beyer Miriam Dibos Annika Wandel Veit Phillip Christoph Ammer-Herrmenau Albrecht Neesse Christian Schulz Jörg Schirra Julia Mayerle Ujjwal Mukund Mahajan Department of Medicine II LMU University HospitalMunich 81377Germany Department of Endoscopy Maria Sklodowska-Curie National Research Institute of OncologyGliwice 44-113Poland Department of Internal Medicine II School of MedicineUniversity Hospital Rechts der IsarTechnical University of MunichMunich 81675Germany Department of Gastroenterology Gastrointestinal Oncology and EndocrinologyUniversity Medical CenterGöttingen 37075Germany

BACKGROUND Biliary microlithiasis/sludge is detected in approximately 30%of patients with idiopathic acute pancreatitis(IAP).As recurrent biliary pancreatitis can be prevented,the underlying aetiology of IAP should be *** To develop a machine learning(ML)based decision tool for the use of endosonography(EUS)in pancreatitis patients to detect sludge and *** We retrospectively used routinely recorded clinical and laboratory parameters of 218 consecutive patients with confirmed AP admitted to our tertiary care hospital between 2015 and *** who did not receive EUS as part of the diagnostic work-up and whose pancreatitis episode could be adequately explained by other causes than biliary sludge and microlithiasis were *** trained supervised ML classifiers using H_(2)*** automatically selecting the best suitable predictor model to predict microlithiasis/*** predictor model was further validated in two independent retrospective cohorts from two tertiary care centers(117 patients).RESULTS Twenty-eight categorized patients’variables recorded at admission were identified to compute the predictor model with an accuracy of 0.84[95%confidence interval(CI):0.791-0.9185],positive predictive value of 0.84,and negative predictive value of 0.80 in the identification cohort(218 patients).In the validation cohort,the robustness of the prediction model was confirmed with an accuracy of 0.76(95%CI:0.673-0.8347),positive predictive value of 0.76,and negative predictive value of 0.78(117 patients).CONCLUSION We present a robust and validated ML-based predictor model consisting of routinely recorded parameters at admission that can predict biliary sludge and microlithiasis as the cause of AP.

关键词： Acute pancreatitis Idiopathic acute pancreatitis Biliary pancreatitis Microlithiasis Sludge Endosonography

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Finite Element Approach for the Solution of First-Order Differential Equations

引用

Journal of Applied Mathematics and Physics 2020年第10期8卷 2072-2090页

作者： André Schmidt Horst R. beyer Matthias Hinze Evangelos N. Vandoros Institute for Nonlinear Mechanics Stuttgart Germany Instituto Tecnológico Superior de Uruapan Uruapan México

The finite element method has established itself as an efficient numerical procedure for the solution of arbitrary-shaped field problems in space. Basically, the finite element method transforms the underlying differential equation into a system of algebraic equations by application of the method of weighted residuals in conjunction with a finite element ansatz. However, this procedure is restricted to even-ordered differential equations and leads to symmetric system matrices as a key property of the finite element method. This paper aims in a generalization of the finite element method towards the solution of first-order differential equations. This is achieved by an approach which replaces the first-order derivative by fractional powers of operators making use of the square root of a Sturm-Liouville operator. The resulting procedure incorporates a finite element formulation and leads to a symmetric but dense system matrix. Finally, the scheme is applied to the barometric equation where the results are compared with the analytical solution and other numerical approaches. It turns out that the resulting numerical scheme shows excellent convergence properties.

关键词： Finite Element Method First-Order Differential Equations Fractional Powers of Operators

来源：

维普期刊数据库评论