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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.

The injectable progestin depot-medroxyprogesterone acetate (DMPA) is a popular contraceptive choice in sub-Saharan Africa although mouse models indicate it weakens genital epithelial integrity and barrier function and increases susceptibility to genital infection. The intravaginal ring NuvaRing® is another contraceptive option that like DMPA suppresses hypothalamic pituitary ovarian (HPO) axis function with local release of progestin (etonogestrel) and estrogen (ethinyl estradiol). As we previously reported that treating mice with DMPA and estrogen averts the loss of genital epithelial integrity and barrier function induced by DMPA alone, in the current investigation we compared genital levels of the cell-cell adhesion molecule desmoglein-1 (DSG1) and genital epithelial permeability in rhesus macaques (RM) treated with DMPA or a NuvaRing®re-sized for RM (N-IVR). While these studies demonstrated comparable inhibition of the HPO axis with DMPA or N-IVR, DMPA induced significantly lower genital DSG1 levels and greater tissue permeability to intravaginally administered low molecular mass molecules. By identifying greater compromise of genital epithelial integrity and barrier function in RM administered DMPA vs. N-IVR, our results add to the growing body of evidence that indicate DMPA weakens a fundamental mechanism of anti-pathogen host defense in the female genital tract.

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.

The Open Databases Integration for Materials Design (OPTIMADE) consortium has designed a universal application programming interface (API) to make materials databases accessible and interoperable. We outline the first stable release of the specification, v1.0, which is already supported by many leading databases and several software packages. We illustrate the advantages of the OPTIMADE API through worked examples on each of the public materials databases that support the full API specification.

The FY-4B satellite is one of the second generation of China's geosynchronous meteorological satellites aiming at numerical weather forecasts. The space environment monitoring package (SEMP) onboard the FY-4B is a comprehensive instrument package for plasma, high-energy particle, and energetic neutral particle measurements. The low-energy particle analyzer (LEPA) is one of the instruments of the SEMP and consists of two top hat electrostatic analyzers designed for plasma detection. The electron and ion sensors are back-to-back assembled and are integrated to a shared electronic box. It measures the three-dimensional velocity distribution of low-energy electrons and ions on the geosynchronous orbit. In this paper, we present the ground calibration and in-flight performance of the instrument. With the electrostatic deflectors and the cylindrically symmetric structure, the instrument provides high-cadence measurements of electron and ion velocity distributions with a wide field of view (FOV) of 180° by 100°, an angular resolution of 16.7° × 20°, and a broad energy range for both the electrons and ions from tens of eV to above 30 keV, with a 1 s time resolution. The geometric factors of the electron and ion analyzers are 1.1 × 10−3 cm2·sr·eV/eV and 1.4 × 10−3 cm2·sr·eV/eV, respectively, which fulfills the requirements of the low-energy plasma measurement. The LEPA monitored typical space environment disturbance such as geomagnetic storms and successfully recorded the responses of plasma energy fluxes. Satellite surface charging events were measured, with the highest potentials of −2000 V in the shadow period and −500 V in the nonshadow period. [ABSTRACT FROM AUTHOR]