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Bone is the most common metastatic site of advanced breast cancer. Bone related events caused by bone metastasis seriously affect the quality of life and survival time of patients. Therefore, in order to improve the quality of life and prolong the survival time of breast cancer patients with bone metastases, it is of great clinical value to investigate the occurrence and development mechanism of bone metastases, explore early diagnosis methods, and pursue abundant and effective treatment methods and drugs for bone metastases. This article mainly reviews the new research progress of bone metastasis of breast cancer from the aspects of molecular mechanism, imaging and biological diagnosis methods, systematic treatment, in order to provide more reference for clinical diagnosis and treatment.

The accuracy of traditional milling force prediction model is low, and it is difficult to provide effective support for the reasonable selection of process parameters in practical production, by synthetically considering the equivalent turning force model of working angle, cutting edge arc and radius of tool tip arc, in this model, the actual turning tool is equivalent to the ideal turning tool model to identify the material constant, the chip flow angle and the average friction angle in the material constitutive equation, according to the oblique cutting model, the shear stress on the main shear plane and the F0 vector of the unit cutting force at different cutting speeds are calculated, thus the instantaneous cutting force on the front face of the end mill can be calculated, the three-dimensional cutting force of end mill in X-Y-Z coordinate system is obtained by coordinate transformation. The prediction of the cutting force model is verified by simulation and experiment.

This study investigates the AD574, a 12-bit analog/digital converter (ADC) produced by American Analog Devices, Inc. (ADI) using bipolar/I2L technology. The test samples are subjected to a total ionizing dose (TID) of 400 Gy(Si) under 60Co γ irradiation. The samples with and without the TID are then subjected to a single-event upset (SEU) test, and the upset times of the output codes under the input signal conditions of 0 V, 1 V, and 2.5 V are obtained. The test results indicate that, after accumulating a total dose of 400 Gy(Si), the upset of the AD574 output code shifts toward the right of the center code value, resulting in a change in the upset times. Furthermore, the mechanism of the TID-SEU synergistic effect for the AD574 is preliminarily analyzed; it is believed that this phenomenon is related to the sensitivity of the ADC internal comparator single-event transient (SET). The amplitude and width of the SET pulse of the comparator with the TID increase significantly; this causes a change in the AD574 output code value upset distribution and the number of upset times. This study on the TID-SEU synergistic effect serves as a useful reference for aerospace components with radiation hardness.

BackgroundBipolar devices used in space radiation environment for a long time are simultaneously threatened by the total ionization dose (TID) effect and single event transient (SET), and there is a synergistic effect between TID and SET. The enhanced low dose rate sensitivity (ELDRS) effect unique to bipolar devices may affect the synergistic effect.PurposeThis study aims to investigate the physical mechanism of TID's impact on the SET in bipolar operational amplifier LM158.MethodsFirst of all, the LM158 samples were irradiated by 60Co γ-ray of a high dose rate of 0.1 Gy·s-1(Si) and a low dose rate of 1×10-4 Gy·s-1(Si). Then, the heavy ion (Tantalum) irradiation test was performed after the total dose was accumulated to 1 000 Gy(Si). The output single event transients of irradiated LM158 were observed by oscilloscope, and all the collected SETs were saved in computer and processed by MATLAB programming.ResultsThe experimental results show that the TID of bipolar operational amplifier LM158 causes the SET pulse amplitude to decrease and pulse width to expand. At the same time, compared with the high dose rate irradiation condition, the SET pulse width of LM158 is expanded by 50% under the low dose rate irradiation condition.ConclusionsThe study indicates that the interface trap charge accumulated in the bipolar transistor is the fundamental reason for the synergistic effect of TID and SET.