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The extended Kantorovich method (EKM) is implemented to numerically solve the elastic buckling problem of thin skew (parallelogram) isotropic plate under in-plane loading resting on the Pasternak elastic foundation. EKM has never been applied to this problem before. Investigation of the EKM accuracy and convergence is conducted. Formulations are based on classical plate theory (CPT). Stability equations and boundary conditions terms are derived from the principle of the minimum total potential energy using the variational calculus expressed in an oblique coordinate system. The resulting two sets of ordinary differential equations are solved numerically using the Chebfun package in MATLAB software. In-plane compression and shear loads are considered along with various boundary conditions and aspect ratios. Results are compared to the analytical and numerical solutions found in the literature, and to the finite element solutions obtained using ANSYS software. The effects of the skew angle, stiffness of elastic foundation, and aspect ratio on the buckling load are also investigated. For plates with zero skew angle, i.e. rectangular plates, with various boundary conditions and aspect ratios under uniaxial and biaxial loading resting on elastic foundation, the single-term EKM is found accurate. However, more terms are needed as the skew angle gets bigger. The multi-term EKM is found accurate in the analysis of rectangular and skew plates with various boundary conditions and aspect ratios under uniaxial, biaxial, and shear loading resting on elastic foundation. Using EKM in buckling analysis of thin skew plates is found simple, accurate, and rapid to converge.

von Willebrand disease (VWD) is frequently ignored as a cause of menorrhagia. We investigated Egyptian women complaining of heavy menstrual bleeding (HMB) and/or other bleeding symptoms to detect potential VWD cases. Seventy-five female patients complaining of HMB and/or bleeding symptoms and 38 age-matched healthy female controls went through a family history questionnaire, a physical examination and were evaluated for bleeding score, pictorial blood assessment chart (PBAC), complete blood count, serum ferritin, blood group, prothrombin time, activated partial thromboplastin time, factor VIII (FVIII) activity, von Willebrand factor (VWF) ristocetin cofactor (RCo) activity, antigen (Ag), and RCo/Ag ratio. Sixty-eight of 75 patients presented with HMB, out of which 46 had no organic pathology and 7 presented other bleeding symptoms. Six patients were diagnosed with VWD, three with HMB, two with other bleeding symptoms and one with family history of VWD. Two related VWD patients were diagnosed in the control group. There were significant differences in bleeding and PBAC scores, ferritin level, FVIII activity, VWF:RCo and VWF:Ag between VWD patients and controls. This study indicated a high prevalence of VWD among patients with HMB without organic pathology (6.5%) and demonstrated the sensitivity of diagnostic parameters of VWD patients in an outreach campaign. The inexpensive bleeding and PBAC scoring systems are valuable to exclude cases without objective bleeding symptoms. Raising gynaecologists awareness about hereditary bleeding disorders is important to ensure a proper diagnosis and possible referral of these patients. Management of these patients with comprehensive medical care services under a multidisciplinary team would be ideal.

Functionally graded materials (FGM) are increasingly used in the engineering field. In many applications, FGMs are modelled as plates. Plates made of functionally graded materials (FGPs) are mostly designed to perform under elevated temperatures. In those circumstances, they are often under the combined effect of thermal and mechanical loads. There have been many studies on buckling analysis of FGP under either mechanical or thermal loads; however, only a few studies have addressed the combined effect of both loads acting together. This article focuses on the review of research on buckling analysis of FGP under the combined thermal and mechanical loads.

With plate-buckling problem still being an active area of research in the field of mechanics of materials, researchers need to validate the proposed solutions and theories, using analysis tools such like ANSYS, which is a robust general-purpose finite element analysis tool. This article investigates modeling and buckling analysis of rectangular plates in ANSYS® Mechanical APDL, Release 17.1, through a series of comparative studies conducted on various models and options. Shell and solid models of homogeneous and functionally graded plate (FGP) using various elements are investigated. Expressing boundary conditions on both shell and solid models of plate for buckling analysis is discussed. Procedures of buckling analysis in ANSYS are presented and effects of meshing, boundary conditions and element options are examined though comparative studies. Results obtained from ANSYS are compared to various analytical solutions.