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The product characteristics and maintenance characteristics of space complex repairable facilities were analyzed to aim at the maintenance requirements with a large number of on-orbit replaceable units, complex systems, and high operation accuracy. An intelligent induced maintenance system for space application facilities was developed, and unique evaluation criteria were established. The system, key technologies, and application effects are verified through typical application cases and comparative experiments. The results show that the implementation of the system can effectively reduce the workload of the astronauts in orbit and improve the work efficiency and provide new cooperation means for the astronauts to solve the urgent and unexpected tasks in orbit.

Zhou S, Cui Y, Yu D, Liang J, Zhang M, Ye W. Onco Targets Ther. 2017;10:2527–2538. The Editor and Publisher of OncoTargets and Therapy are retracting the published article. Concerns were raised regarding the duplication of western blot images and an investigation found duplicated images in Figures 3 and 6. Specifically, The image in Figure 3D, TE10, c-caspase-3, has been duplicated with the same image from Figure 6C, TE10, c-PARP. The image in Figure 3D, TE10, c-PARP has been duplicated with the same image from Figure 3D, TE11, c-PARP. The image in Figure 3D, TE10/miR-381(+), c-caspase-3, has been duplicated with the same image from Figure 3D, TE11/miR-NC(-), Total PARP. The image in Figure 3D, TE11, Total PARP, has been duplicated with the same image from Figure 6C, TE11, Total caspase-3. The image from Figure 6C, TE10/shXIAP(+), c-PARP has been duplicated with the same image from Figure 6C, TE11/shcontrol(-), Total caspase-3. The authors cooperated with the investigation but were unable to provide a satisfactory explanation regarding the duplicated images and were unable to verify the published work. Therefore, the Editor and Publisher are retracting the article and the authors have been notified. We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as “Retracted”.

Twelve undescribed cyclopentanoid monoterpenes, Jiopiasins A-K and 6-epi-rehmaglutin A, and 19 known compounds were isolated from the whole plant of Rehmannia piasezkii Maxim. The structures of these compounds, especially their absolute stereochemistry, were established by extensive spectroscopic analysis, various quantum chemical calculations, and/or X-ray diffraction analyses. Furthermore, in vitro assays, some compounds exhibited moderate hepatoprotective activities against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage.

ZnS is a promising photocatalyst in water purification, whereas its low photon efficiency and poor visible-light response restrict its application. Constructing composites may help solve these problems. In this work, Ag2O was introduced to ZnS for the first time based on their energy band characteristics to form a novel ZnS/Ag2O composite photocatalyst. In the model reaction of degrading methylene blue, the as-designed catalyst exhibited high catalytic activity among a series of ZnS-based composite photocatalysts under similar conditions. The catalytic rate constant was up to 0.138 min−1, which is 27.4- and 15.6-times higher than those of ZnS and Ag2O. This composite degraded 92.4% methylene blue in 50 min, while the ratios were 31.9% and 68.8% for ZnS and Ag2O. Catalytic mechanism study based on photoluminescence and radical-scavenging experiments revealed that the enhanced photocatalytic activity was attributed to the composite structure of ZnS/Ag2O. The structure not only facilitated the separation and transmission of photogenerated carriers but also extended the light response range of the catalyst. The as-designed ZnS/Ag2O composite is promising in degrading organic pollutants in water.

Background Cyclin-dependent kinase-like 3 (CDKL3) is a putative protein serine kinase and plays an important role in the regulation of cell growth and/or differentiation. However, studies on the function of CDKL3 in esophageal squamous cell carcinoma (ESCC) is limited. In our study, we explored the role and prognosis of CDKL3 in ESCC and underlying mechanism. Materials and methods The expression of CDKL3 was investigated by quantitative reverse transcription polymerase chain reaction and immunohistochemical staining. CDKL3 expression was downregulated by the RNAi-mediated knockdown. The functions of CDKL3 on cell growth were assessed by Celigo image cytometry, MTT assay, cell-cycle analysis, Annexin V assay, and caspase-3/7 activity analysis. The effect of CDKL3 on cellular invasive was investigated by the Transwell assay. Pathscan Stress Signaling Antibody Array was used to study the underlying mechanism. Additionally, the association between the survival and CDKL3 expression in ESCC were evaluated based on the TCGA data. Results CDKL3 was highly expressed in ESCC tissues and cell lines. TE-1 cells transfected with CDKL3-shRNA-lentivirus significantly decreased CDKL3 expression and resulted in inhibiting cell proliferation, inducing the S-phase cell-cycle arrest, attenuating cellular invasive and increasing cell apoptosis. The expression of pERK1/2, p-Akt, p-Smad2, p-p38 mitogen-activated protein kinase, cleaved caspase-7, and phospho-Chk1 were significantly decreased by CDKL3 knockdown. In addition, high expression of CDKL3 was associated with shorter overall survival. Conclusion Our findings suggest that higher expression of CDKL3 is correlated with poor prognosis in patients with ESCC and play a vital role in the malignant phenotype of ESCC cell lines, which indicating that CDKL3 may be as a new therapeutic target in ESCC.

Five new iridal-type triterpenoid derivatives with 6/5/6 tricyclic ring skeleton (1-5) were obtained from the rhizomes of Belamcanda chinensis. Their structures were determined on the basis of detailed spectroscopic data and ECD calculation. Compounds 1-5 possessed the same 6/5/6-fused carbon skeleton as Belamchinenin A, which further enriched this kind of iridals. In vitro bioassay, compounds 2 and 3 exhibited 51.95 and 54.52% inhibitory activities, respectively, against Fe

Objective The technique of radiotherapy is associated with the recurrence pattern and prognosis of postoperative treatment for medulloblastoma. Our aim was to assess recurrence patterns and survival in patients with medulloblastoma between three-dimensional conformation (3D-CRT) and intensity modulated radiotherapy (IMRT). To analyze the factors affecting the prognosis, such as the use of 3D-CRT or IMRT, the time interval of surgical and radiotherapy, whether there is chemotherapy and chemotherapy regimen.Methods In this study, 36 patients with medulloblastoma were conducted investigating and data were analyzed from May 2009 to September 2017. The median survival of each group was calculated for different clinical stages,pathological types and treatment methods. The PFS and OS for patients curves were derived by Kaplan-Meier estimation, and which were calculated using the Cox proportional hazards model between the IMRT and 3D-CRT treatment groups.Results Up to the follow-up date, 7 of the 9 patients in the 3D-CRT group had recurrence and 9 of the 27 patients in the IMRT group had recurrence. The 2-year and 5-year PFS of the IMRT group were 74.1% and 65.8%, and which of the 3D-CRT group were 55.6% and 22.2%, respectively. The PFS was significantly higher for patients treated with IMRT compared with 3D-CRT (P0.05). There was no statistical difference in the chemotherapy-free group, the EP chemotherapy regimen and the temozolomide (TMZ) chemotherapy group in the 2-year and 5-year PFS and OS(P>0.05). The results of multivariate Cox proportional hazards model analysis showed that the residual, recurrence or metastasis before radiotherapy were independent prognostic factors affecting PFS(P

In order to predict the reliability of semiconductor lasers, an accelerated degradation test (ADT) was proposed as an element of reliability testing. Temperature-stressed ADT was applied for 8 Semiconductor lasers which used in space missions, and the degradation characteristics of output power of semiconductor lasers were studied. Then, a reliability model based multi-output Gaussian process regression (MOGP) was proposed to evaluate the lifetime and reliability for laser diodes. The advantage of the proposed MOGP based method is that it utilizes the output correlation between multiple degradation traces to make the outputs utilize each other's information and provide more accurate prediction than single modeling. Thereby improving the prediction accuracy. Furthermore, verifying applications and cases studies are discussed to prove the generality and practicability of the proposed reliability prediction model. Results show that the accuracy of the proposed MOGP based method is twice that of the SVM method.

As equipment becomes more and more complex, it is increasingly difficult to manually extract and select fault features manually based on expert experience or signal processing techniques. In addition, the shallow model such as BP neural network and SVM have trouble to deal with the complex mapping relationship with respect to the measured signal and the health condition of the equipment, who faces the problem of dimensional disaster. Combined with the advantages of deep confidence network (DBN) in features extraction and deal with high-dimensional and nonlinear samples, a fault feature extraction and diagnosis method based on deep confidence network for gearbox is investigated in this framework. The method uses the original time domain signal to train the deep confidence network and completes the intelligent diagnosis through deep learning. The preponderance is that it can take out the dependence on a great quantity of signal processing techniques and diagnostic experience, and accomplish the extraction of fault features and the intelligent diagnosis of health status with the characteristic of self-adaption. The method has no periodic requirements for time domain signals, and has strong versatility and adaptability. The experimental results of the fault diagnosis for the planetary gearbox demonstrated the feasibility and superiority of the presented method.

The main factor, which leads to semiconductor lasers degradation in space mission experiments, is the introduction of lattice defects in the detector material produced by radiation. Therefore, a new remaining useful life (RUL) prediction method considering radiation effect is presented. The prediction method is based on failure mechanisms and particle filters, which realizes the combination of a physical model and data-driven method. The particle filters can abundantly employ degradation data and avoid ignoring the failure mechanism. Accelerated degradation testing (ADT) is proposed for effectively assessing the proposed prediction method, in which the proton radiation is selected as the accelerated stress. The prediction results are compared with other methods to verify the accuracy and effectiveness of the proposed prediction method.

Ten new iridal-type triterpenoid derivatives, polycycloiridals K-T (

Schefflera kwangsiensis Merr. ex H.L. Li (Araliaceae) is a widely used traditional Chinese medicine for pain management in the clinic. In the present study, we isolated a previously undescribed lupane saponin, designated as schekwanglupaside C (Sch C) from the ethanolic extract of S. kwangsiensis. The structure of Sch C was determined by comprehensive spectroscopic and spectrometric analyses and chemical degradation. In primary cultured cortical neurons, Sch C altered the pattern of spontaneous Ca

Background Brain metastasis is an important cause of breast cancer-related death. Aim We evaluated the relationships between breast cancer subtype and prognosis among patients with brain metastasis at the initial diagnosis. Methods The Surveillance, Epidemiology, and End Results database was searched to identify patients with brain metastasis from breast cancer between 2010 and 2015. Multivariable Cox proportional hazard models were used to identify factors that were associated with survival among patients with initial brain metastases. The Kaplan–Meier method was used to compare survival outcomes according to breast cancer subtype. Results Among 752 breast cancer patients with brain metastasis at diagnosis, 140 patients (18.6%) underwent primary surgery and 612 patients (81.4%) did not undergo surgery, while 460 patients (61.2%) received chemotherapy and 292 patients (38.8%) did not receive chemotherapy. Multivariable analysis revealed that, relative to HR+/HER2– breast cancer, HR–/HER2– breast cancer was associated with significantly poorer overall survival (hazard ratio: 2.52, 95% confidence interval: 1.99–3.21), independent of age, sex, race, marital status, insurance status, grade, liver involvement, lung involvement, primary surgery, radiotherapy, and chemotherapy. The median overall survival intervals were 12 months for HR+/HER2−, 19 months for HR+/HER2+, 11 months for HR−/HER2+, and 6 months for HR–/HER2– ( P < .0001). Relative to HR+/HER2– breast cancer, HR–/HER2– breast cancer was associated with a significantly higher risk of mortality among patients, and the association was stronger among patients who received chemotherapy ( p for interaction = .005). Conclusions Breast cancer subtype significantly predicted overall survival among patients with brain metastasis at diagnosis.

To solve the problem of difficulty in extracting fault features from the vibration signal of centrifugal pump, this paper proposes an integrated method based on multi-scale entropy (MSE) and local characteristic-scale decomposition (LCD) for centrifugal pump fault diagnosis. Firstly, LCD is applied to decompose the signal into a series of components. Secondly, MSE is extracted as the signal feature. Thirdly, probabilistic neural network (PNN) is employed for fault recognition. Finally, a case is studied based on the experimental data of a centrifugal pump, and the present method achieves the accuracy of 98.00%. Compared with other fault diagnostic methods, the proposed approach exhibits the best performance. The results validate the effectiveness and superiority of the present method.

Accelerated degradation test (ADT) as an element of reliability test is proposed to predict the reliability of High Power Laser Diodes. Temperature stress ADT is demonstrated for 8 High Power Laser Diodes which used in space missions, and both output power and internal resistance of High Power Laser Diodes are researched. Based on Geometric Brownian motion, the lifetime of tested High Power Laser Diodes is about 53667 hours when only considering luminous flux attenuate. However, when the temperature drift is considered as one evaluating factor, the lifetime estimated is about 107500 hours. Results show that for the evaluation of High Power Laser Diodes, both luminous flux degradation and temperature drift should be taken into consideration. It is proved that the lifetime of this kind High Power Laser Diodes meets requirement of space mission, which does not need to be set as orbit replacement unit.

With the continuous progress of the space station project, the rotary mechanism is widely used in the space station. Serious failure of rotating mechanism can cause motor burnout and then safety problems. Therefore, it is necessary to monitor and diagnose rotating mechanism. The vibration signal of the rotating mechanism is nonlinear and non-stationary. Therefore, the acceleration sensor vibration signal is decomposed by CEEMD method to get the intrinsic mode function. Next, Fourier transform is used to obtain time-frequency information according to the obvious components of fault characteristics, and the information entropy of time-frequency information is calculated. The degree of dimensionality reduction about fault feature is determined by selecting the number of principal components through adaptive cumulative contribution. Finally, the fault feature is trained by support vector machine and tested with data. Experimental results show that the optimized method is less computational and can accurately extract fault feature information.