RESUMEN
Alpha particle X-ray spectrometer (APXS) is one of the payloads of Chang'E-3 lunar rover, the scientific objective of which is in-situ observation and off-line analysis of lunar regolith and rock. Distance measurement is one of the important functions for APXS to perform effective detection on the moon. The present paper will first give a brief introduction to APXS, and then analyze the specific requirements and constraints to realize distance measurement, at last present a new near infrared distance sensing algorithm by using the inflection point of response curve. The theoretical analysis and the experiment results verify the feasibility of this algorithm. Although the theoretical analysis shows that this method is not sensitive to the operating temperature and reflectance of the lunar surface, the solar infrared radiant intensity may make photosensor saturation. The solutions are reducing the gain of device and avoiding direct exposure to sun light.
RESUMEN
Alpha particle X-ray spectrometer (APXS) is one of the payloads of Chang'E-3 lunar rover of China's Lunar Exploration Project. The present paper introduces briefly the components of APXS, how it works and its working environment on the lunar surface. The environmental temperature effect has been studied with simulations and experiments, and the results show that the temperature of the APXS sensor will be varying during the measuring on the lunar surface. And another experiment reveals that the energy resolution becomes worse if the sensor's temperature is varying. In this paper, a correction method based on Pearson's chi-squared test is presented. The method can improve the energy resolution when the sensor's temperature is varying. We have tested the method with the spectra acquired by APXS in the temperature varying period of Temperature Cycling Test, and the results show that the method is efficient and reliable.
RESUMEN
We aimed to elucidate whether and how BRCA1 mislocalization [including membranous nuclear (MN) forms and negative patterns] is associated with the occurrence and the prognosis of breast cancer in young Taiwanese women. A case-control study was carried out to enroll 84 patients with breast cancer and 81 patients with benign breast disease. The subcellular localization of BRCA1 was examined using immunofluorescent assays on fresh tissue touch-imprinting slides to classify staining results into diffuse nuclear (DN), MN, and negative staining. Genetic variations of BRCA1 nuclear localization/transportation-related sequences were analyzed by cDNA sequencing of both nuclear localization signals (NLS) and nuclear export signals (NES). The BRCA1 antibody was verified by two other published ones. Comparisons of immunofluorescent assay with immunohistochemical and H&E staining methods were also performed. BRCA1 mislocalization conferred a 3.13-fold [95% confidence interval (CI): 1.31-7.50] risk of developing breast cancer for the MN form and a 5.79-fold (95% CI:1.58-21.23) risk for BRCA1-negative cases compared with DN staining. However, no genetic variant was found in the NES or the NLS region of the BRCA1 gene. In terms of prognosis, BRCA1 mislocalization showed a 3.5-fold (95% CI: 1.20-10.09) increased risk of breast cancer death compared with DN staining after adjusting for tumor node metastasis stage. BRCA1 MN forms and BRCA1-negative patterns led to a higher risk of carcinogenesis and a poor prognosis of breast cancer. Such BRCA1 mislocalization may not be directly caused by the genetic effects of the NLS and NES domains, but stem from nongenetic modifications (such as epigenetic silencing).