Objective: To observe the clinical efficacy of targeted sealing with high viscosity bone cement and secondary injection of low viscosity bone cement in the treatment of OVCFs patients with the fracture lines involved vertebral body margin.
Methods: The elderly patients who underwent vertebroplasty for osteoporotic vertebral compression fractures from January 2019 to September 2021 were selected as the screening objects. Through relevant standards and further CT examination, 56 patients with fracture lines involving the anterior wall or upper and lower endplates of the vertebral body were selected for the study.
In magnetic bearing systems, the air gap between the stator and the rotor is generally measured with an eddy current displacement sensor. However, the inductive displacement sensor (IDS) is a preferred choice due to its structural consistency with magnetic bearings, which contributes to a compact system design. While most of the reported IDS research studies are based on three-dimensional finite element method (3D FEM) simulation and the IDS of such studies is designed with a half-bridge structure, in this paper, a higher sensitivity IDS with a full-bridge structure is proposed.
View Article and Find Full Text PDFThis paper reports a dual-butterfly structure gyroscope based on the traditional butterfly structure. This novel structure is composed of two butterfly structures, each of which contains a main vibrational beam, four proof masses, and a coupling mechanism. The coupling mechanism in this proposed structure couples the two single butterfly structures and keeps the driving mode phases of the two single butterfly gyroscopes exactly opposite, increasing the double difference of traditional butterfly gyroscopes to a quad difference, which has the potential advantage of improving bias instability and g-sensitivity.
View Article and Find Full Text PDFA method was developed for the determination of 19 perfluoroalkyl acids (PFAs) in lamb liver by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/ MS) combined with dispersive solid phase extraction. The sample was extracted with acidified acetonitrile, and then cleaned-up by a mixture of N-propylethylenediamine (PSA), C18 and graphitized carbon black (GCB) sorbents. The 19 PFAs were analyzed by HPLC-MS/MS with a C18 chromatographic column, adopting the multiple reaction monitoring (MRM) mode with negative electrospray ionization.
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