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Crowned dens syndrome(CDS) is a major imaging manifestation of "coronary" calcified deposits around the odontoid, with pain, stiffness, fever, and even cervical cord compression in the upper head and neck. It was first described by Bouvet et al. in 1985, and the onset was generally thought to be caused by crystal deposition. The clinical manifestations of CDS are often similar to meningitis and often accompanied by an increase in inflammatory markers in the blood. As a result, it is very easy to obtain missed diagnosis and misdiagnosis, and it is clinically prone to obtain wrong or unnecessary treatment. At present, the diagnosis of CDS is based on the imaging findings in CT as a "golden standard". NASIDs drugs and corticosteroids are the main treatment. The prognosis is also generally good, and the imaging findings of the patients with the disease disappear completely within 3 months.

Stress distribution of the thin circular quartz crystal has been analyzed by ANSYS finite element simulation when subjected to radial force. A quartz crystal resonator with same base and different electrode is designed. When putting on the radial force, we research the force sensitive nature of this resonator and its relationship with the force azimuth. The results show that, It is closely to the resonator structure and the force position, that the force sensitive character of quartz resonator with same crystal and different position. Selecting the appropriate force position, we can receive greater diversity of force sensitivity. The output using difference frequency between the different resonators can suppress interference factors. Making the difference frequency signal as a superposition of complex processing can enhance this resonator overall force sensitive. With the difference frequency and signaling complex, the force-frequency conversion coefficient of this resonator is up to 500Hz / N.

The force sensitive characteristic of integrated quartz crystal resonator assembled on one quartz crystal substrate with a certain radial direction force are studied, and it is also studied that the force sensitive characteristic of output frequency which is the mixing frequency by resonant frequency corresponded to the resonators in the different position of the same quartz crystal wafer outputted in difference frequency way. The research result shows the force sensitive characteristic of AT-cut integrated three-electrode quartz crystal resonator outputted in difference frequency way is 1.3 times of that of the traditional single-electrode resonator. The force sensitive characteristic of the integrated four-electrode resonator is a little bit smaller, but two sets of output can be obtained at the same time. The frequency stability of all integrated quartz resonator can get to the magnitude of 10-10 and relative frequency variation is about ±5ppm in the range of -50°C to 60°C.

By energy trap theory and normalized criterion, this paper theoretical analyzed the mono-base multi-electrode quartz crystal resonator dimension structure，and used ANSYS finite element analysis to simulate the stress distribution in the crystal when quartz crystal resonator exerted with different position of radial arc force. Theory and simulation get the optimal electrode structure and the best azimuth angle to add force, provide reference to design new mono-base multi-electrode quartz crystal resonator.

Based on the analysis of stress distribution in the medium of semi-infinite anisotropic thin medium plates with centralized forces, in the method of protracting and adding additional stress, the relation of relative frequency variation and adding force azimuth and strength of the plates with the diameter centralized forces can be gained. And it is compared with relative frequency variation of resonation with central electrode. Meanwhile by using finite element method to analyze stress variation in different places when the quartz plate is with the diameter centralized forces, and the frequency variation characteristic of resonator in different places is also be measured in the actual evaporated electrode way.

Since MDM2 is an inhibitor of the p53 tumor suppressor, disrupting the MDM2-p53 interaction is a promising approach for cancer therapy. Here, we used molecular dynamics simulations followed by free energy decomposition analysis to study conformational changes in MDM2 induced by three known spiro-oxindole inhibitors. Analysis of individual energy terms suggests that van der Waals and electrostatic interactions explain much of the binding affinities of these inhibitors. Binding free energies calculated for the three inhibitors using the molecular mechanics-generalized Born surface area model were consistent with experimental data, suggesting the validity of this approach. Based on this structure-function analysis, several novel spiro-oxindole derivatives were selected and evaluated for their ability to block the MDM2-p53 interaction in vitro. These results suggest that combining in silico and experimental techniques can provide insights into the structure-function relationships of MDM2 inhibitors and guide the rational design of anticancer drugs targeting the MDM2-p53 interaction.