Free vibration and buckling of three-phase bidirectional functionally graded sandwich (BFGSW) plates are studied in this paper for the first time by using an efficient nine-node quadrilateral (Q9) element. The core of the sandwich plates is pure ceramic, while the two skin layers are of a three-phase bidirectional functionally graded material. The element is derived on the basis of the Mindlin plate theory and linked interpolations. Fundamental frequencies and buckling loads are computed for the plates with various boundary conditions. Numerical result shows that convergence of the linked interpolation element is faster compared to the conventional Lagrangian interpolation Q9 element. Numerical investigations are carried out to highlight the influence of the material gradation and the side-to-thickness ratio on the vibration and buckling behaviour of the plates.

In tuning fork micro-gyroscopes, two outer frames are connected indirectly or directly by using the linking elements. Their driving vibration should be exactly opposite to cause the opposite sensing modes in the direction perpendicular to driving one. These opposite driving vibrations are obtained by using a mechanical structure named the diamond-shaped frame. This paper reports mechanical responses of two outer frames in a proposed model of tuning fork gyroscope when an external force with different types is applied to them. The results show that the presence of a diamond-shaped frame guarantees the absolute anti-phase mode for the driving vibrations of outer frames.

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Objective: The importance of a complete resection of high‑grade gliomas (HGGs) has been highlighted in scientific literature, in order to limit tumor recurrence and above all to improve disease‑free survival rates. Several fluorescent biomarkers have been tested to improve intraoperative identification of residual tumor. The fluorescein sodium (FS) are now starting to play an important role in glioma surgery. Under the YELLOW 560nm surgical microscope filter, low-dose FS (5mg/kg) as a fluorescent dye helps in visualization of tumor tissue. Our study provides preliminary results in investigating the safety and efficacy of this technique in patients with HGGs. Subject and method: A prospective, uncontrolled study of 27 patients with HGGs underwent FS-guided resection under YELLOW 560nm surgical microscope filter. We have analyzed the clinical features, size, tumor location, extent of tumor resection, pathologic of HGGs, patient status (Karnofsky Performance Scale) and FS side effects. Result: 7/27 patients (25.9%) were glioma grade III and 20/27 patients (74.1%) were glioma multiforme (GBM). With YELLOW 560nm surgical microscope filter (PENTERO 900 surgical microscope), FS-guided gross total resection (GTR) was achieved in 74.1% and subtotal resection (STR) in 11.1%. No side effects of FS were reported. Conclusion: FS-guided resection of HGGs under the YELLOW 560nm surgical microscope filter was effective and safe.