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After the completion of the three steps of "circling back", the lunar exploration has changed from the short-term single point exploration to the long-term exploration of lunar scientific research stations with the con-struction of lunar surface infrastructure, the higher requirements for the planning and demonstration, overall de-sign, system development and in-orbit exploration of lunar exploration missions are put forward. The thought of model based system engineering (MBSE) is adopted, a model-based forward process for the system analysis of the lunar scientific research station proposal is proposed, and the system model is taken as a carrier to analyze the mis-sion overall, mission requirements and task application scenario. By carrying out the model-based mission analysis of the lunar scientific research station, the process of the mission of the lunar scientific research station has been pre-liminarily realized.

Abstract Background Molecular targeted therapy for non-small cell lung carcinoma (NSCLC) is restricted due to resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). This study evaluated the effects of dual targeting of MEK and PI3K in human EGFR-TKI resistant NSCLC cell lines. Methods EGFR-TKI resistant NSCLC cell lines H1975, H460, and A549, with different mutation and amplification status in EGFR, K-RAS, PIK3CA, and MET genes, were treated with a MEK162 (MEK inhibitor) and BKM120 (PI3K inhibitor) combination or a BIBW2992 (EGFR inhibitor) and ARQ197 (MET inhibitor) combination and assayed for cell proliferation, apoptosis, and cell cycle distribution. Results Dual targeting of MEK and PI3K efficiently inhibited the cell proliferation, induced apoptosis and the G0/G1 cell cycle, and decreased the phosphorylation of ERK1/2, AKT, S6, and 4E-BP1. H460 cells with K-RAS and PIK3CA mutation were most sensitive to MEK162 and BKM120 combinations. H1975 cells with EGFR and PIK3CA mutation and MET amplification were sensitive to BIBW2992 and ARQ197 combinations. Conclusion Dual targeting regulated the proliferation of EGFR-TKI-resistant NSCLC cells, especially mutants in K-RAS and PIK3CA that are promising for EGFR-TKI-resistant NSCLC therapeutics.

In this study, we evaluated the clinical utility of tracheal aspirates α-amylase (AM), pepsin, and lipid-laden macrophage index (LLMI) in the early diagnosis of ventilator-associated pneumonia (VAP) in elderly patients on mechanical ventilation. Within 96 hours of tracheal intubation, tracheal aspirate specimens were collected from elderly patients on mechanical ventilation; AM, pepsin, and LLMI were detected, and we analyzed the potential of each index individually and in combination in diagnosing VAP. Patients with VAP had significantly higher levels of AM, pepsin, and LLMI compared to those without VAP (P < 0.001), and there was a positive correlation between the number of pre-intubation risk factors of aspiration and the detection value of each index in patients with VAP (P < 0.001). The area under a receiver operating characteristic (ROC) curve (AUC) of AM, pepsin, and LLMI in diagnosis of VAP were 0.821 (95% CI:0.713–0.904), 0.802 (95% CI:0.693–0.892), and 0.621 (95% CI:0.583–0.824), the sensitivities were 0.8815, 0.7632, and 0.6973, the specificities were 0.8495, 0.8602, and 0.6291, and the cutoff values were 4,321.5 U/L, 126.61 ng/ml, and 173.5, respectively. The AUC for the combination of indexes in diagnosing VAP was 0.905 (95% CI:0.812–0.934), and the sensitivity and specificity were 0.9211 and 0.9332, respectively. In the tracheal aspirate specimens, the detection rate of AM ≥ cutoff was the highest, while it was the lowest for LLMI (P < 0.001). The detection rates of AM ≥ cutoff and pepsin ≥ cutoff were higher within 48 hours after intubation than within 48–96 hours after intubation (P < 0.001). In contrast, the detection rate of LLMI ≥ cutoff was higher within 48–96 hours after intubation than within 48 hours after intubation (P < 0.001). The risk factors for VAP identified using logistic multivariate analysis included pre-intubation aspiration risk factors (≥3), MDR bacteria growth in tracheal aspirates, and tracheal aspirate AM ≥ 4,321.5 U/L, pepsin ≥ 126.61 ng/ml, and LLMI ≥ 173.5. The detection of AM, pepsin, and LLMI in tracheal aspirates has promising clinical utility as an early warning biomarker of VAP in elderly patients undergoing mechanical ventilation. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) pool integrated the vegetation succession information from several years to thousands of years scales. It is an ideal tool to understand carbon isotope composition change and terrestrial ecosystem pathways. In this study, the Sangong river watershed was taken as a case. We had estimated the change of vegetation and soil organic along a vertical gradient using the carbon isotopic method, and analyzed the variations of mean SOC δ13C values with the annual precipitation, and researched the variations in SOC and δ13C values with profile depth in the study area. The results showed that the SOC δ13C decreased significantly with the increasing annual precipitation (R2=0.97) where the annual precipitation was less than 300 mm. When the annual precipitation was 300 mm~500 mm, the SOC δ13C was not significant changed with the increasing annual precipitation (R2=0.04). The enrichment effect of SOC δ13C with depth was significant in the sample site of pure C3 vegetation, that means lower layer SOC δ13C of profile was greater than the upper layer. The average difference of SOC δ13C between lower layer and upper layer was 1.01‰. The opposite trend of SOC δ13C was presented in the Desert and Shrubland sites. And that, the SOC δ13C value of upper layer closed to C4 vegetation source, and the lower layer closed to C3 vegetation source. Therefore, we can infer that the vegetation may have experienced from C3 to C4 in the sandy desert and terrene desert sites.