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In order to overcome the challenge of quantifying the influence of environmental conditions and the coexistence of multiple failure modes involved in mechanism reliability modelling under different environments. In this paper, we propose a method for the analysis of mechanism reliability that takes into account the influence of environmental factors and failure modes’ correlation, quantifies the influence of environmental factors as the random distribution and degradation path of parameters, and derives the Copula description of failure mode correlation from the historical data of environmental experiments. On the basis of the discrete mechanism dynamics model, the output parameters of the characteristic points are calculated, and the failure rate of each failure mode is calculated based on the failure criterion and the performance margin theory. Additionally, the dynamic change pattern of the mechanism reliability is compared with the Kaplan-Meier estimation of the corresponding environmental test history data to assess the validity of the calculation results. The reliability modelling problem of a motion mechanism of an automatic rifle automaton in a high and low temperature environment is applied to the method, and the reliability calculation results are close to those of Kaplan-Meier estimation of the test history data, and all are within the upper and lower bounds given by the reliability boundary theory, demonstrating the method's validity.

BACKGROUND Sorafenib is the first-line treatment for patients with advanced hepatocellular carcinoma (HCC). Y-box binding protein 1 (YB-1) is closely correlated with tumors and drug resistance. However, the relationship between YB-1 and sorafenib resistance and the underlying mechanism in HCC remain unknown. AIM To explore the role and related mechanisms of YB-1 in mediating sorafenib resistance in HCC. METHODS The protein expression levels of YB-1 were assessed in human HCC tissues and adjacent nontumor tissues. Next, we constructed YB-1 overexpression and knockdown hepatocarcinoma cell lines with lentiviruses and stimulated these cell lines with different concentrations of sorafenib. Then, we detected the proliferation and apoptosis in these cells by terminal deoxynucleotidyl transferase dUTP nick end labeling, flow cytometry and Western blotting assays. We also constructed a xenograft tumor model to explore the effect of YB-1 on the efficacy of sorafenib in vivo. Moreover, we studied and verified the specific molecular mechanism of YB-1 mediating sorafenib resistance in hepatoma cells by digital gene expression sequencing (DGE-seq). RESULTS YB-1 protein levels were found to be higher in HCC tissues than in corresponding nontumor tissues. YB-1 suppressed the effect of sorafenib on cell proliferation and apoptosis. Consistently, the efficacy of sorafenib in vivo was enhanced after YB-1 was knocked down. Furthermore, KEGG pathway enrichment analysis of DGE-seq demonstrated that the phosphoinositide-3-kinase (PI3K)/protein kinase B (Akt) signaling pathway was essential for the sorafenib resistance induced by YB-1. Subsequently, YB-1 interacted with two key proteins of the PI3K/Akt signaling pathway (Akt1 and PIK3R1) as shown by searching the BioGRID and HitPredict websites. Finally, YB-1 suppressed the inactivation of the PI3K/Akt signaling pathway induced by sorafenib, and the blockade of the PI3K/Akt signaling pathway by LY294002 mitigated YB-1-induced sorafenib resistance. CONCLUSION Overall, we concluded that YB-1 augments sorafenib resistance through the PI3K/Akt signaling pathway in HCC and suggest that YB-1 is a key drug resistance-related gene, which is of great significance for the application of sorafenib in advanced-stage HCC.

Clicking on the log data saved by the website, using the big data means to analyze and mine the information stored by massive data, many crucial information of website operation can be learned. This paper adopts Hadoop distributed platform, uses HDFS data storage and Hive to analyze log big data, designs a Web log analysis system and expounds the design process of the system.

This study was conducted to determine the differences and changes in trends of physiological metabolism in the process of adaptation to saline environments and artificial domestication among the subgenus Soja. Glycine max, Glycine gracilis and Glycine soja were used as the experimental material. The determination of mineral contents during different growth periods and the photosynthetic pigments, gas exchange parameters and soluble carbohydrate contents in the initial bloom stage were investigated. The results showed that, NO3, H2PO4, Cu, Zn and B contents and the photosynthetic pigments, gas exchange parameters and photosynthetic product were significantly higher in salt-tolerant wild soybean than in common wild soybean. NO3, H2PO4, SO4, K, Mg, Fe, Cu, Mo and Mn contents were significantly lower in cultivated soybean than in common wild soybean; and Ca and B were significantly higher. The photosynthetic pigments, gas exchange parameters and photosynthetic product at the initial bloom stage in cultivated soybean were significant higher than in common wild soybean and semi-wild soybean. The correlations of H2PO4, SO4, K, Mg, Mo and Mn with photosynthetic characteristic parameters significantly differed among members of Soja. Our study confirmed that mineral contents and photosynthetic characteristics among Soja had evolved towards the different environments and human requirements during long-term natural selection and artificial domestication. These findings will contribute to understanding the evolutionary trend of soybean. © 2016 Friends Science Publishers

Hierarchically structured LDHs are being actively investigated due to their potential applications in bioseparation and catalysis which result from their special surface structures and positively charged nanosheets. This work presents an effective method of fabricating hierarchical LDHs based materials with high surface-to-volume ratios. To do this, the microscaled Al2O3 fibers are fabricated via a simple biotemplate method employing paper fibers as templates and in the second step the nanoscaled Ni-Al LDH platelets are fabricated into hierarchical architectures based on crystal growth on surface of Al2O3 fibers. In order to obtain the multi-component and multi-scale structure LDHs based materials, the ZnO/LDHs composites are obtained by controlling crystal growth process. The developed facile route is highly valuable and feasible for hierarchical porous LDHs based materials for applications in research and industrial fields.

Materials with infrared low emissivity have attracted great attention due to their increasingly important application in both military stealthy and thermal control. Hence, this work describes a facile, green method based on cotton fibers to fabricate hierarchically structured ZnO fibers and nanorod by simply immersion and calcination process. And infrared emissivity value of samples was also investigated. The cotton fiber adsorbed Zn2+ could be converted into ZnO nanorod by controlling reaction temperature and solution pH. The XRD pattern revealed the highly crystalline nature of the samples. In order to enhance the surface optical properties, the surfaces of biomorphic ZnO were modified by bovine serum albumin (BSA). The low infrared emissivity values were obtained in BSA modified samples, indicating that the surface properties of materials may play an important role in infrared emissivity control.

In this paper, a new method based on Hilbert marginal spectrum is presented to solve the problem of coal-rock interface recognition in the top caving process. Coal or waste rock impinges against the tail beam of the hydraulic support. The impact causes the vibration of the tail beam. Because of different intrinsic characteristics, dissimilarities will exist between the two cases. The coal-rock interface is recognized by comparing the Hilbert marginal spectrum. The results show that the proposed method is a promising approach to identifying the coal-rock interface.

In this paper, the atomic magnetic moments and spin-splittings of the six-member ring N2C4 cluster with planar and folding configurations in DNA bases are studied, respectively. The results show that the surprising interplay between the molecular structure and their magnetic property. In the planar configuration, the cluster exhibits antiferromagnetism and ferromagnetism in the ground state and metastable state, respectively. In the folding configuration, it exhibits antiferromagnetism and ferrimagnetism in the ground state and metastable state, respectively.

To generate recombinant avian adeno-associated virus (rAAAV) for gene transfer studies in avian cells, the recombinant plasmid containing the whole genome of AAAV was digested with restriction enzymes to remove the Rep and Cap genes, resulting in AAAV transfer vector pAITR. GFP-expressing cassette was amplified by PCR and inserted into the AAAV transfer vector. The Rep-Cap gene of AAAV amplified by high fidelity PCR was subcloned into eukaryotic expression vector pcDNA3, resulting in an AAAV helper vector pcDNA-ARC. The Rep and Cap genes amplified by high fidelity PCR were subcloned separately into the co-expression vector pVITRO2-mcs, resulting in another AAAV helper vector pVITRO2-ARC. Using calcium phosphate precipitation method, rAAAV-GFP was generated by co-transfecting AAV-293 cells with a cocktail of pAITR-GFP, pcDNA-ARC or pVITRO2-ARC, and adenovirus helper vector pHelper. The three structural proteins VP1, VP2 and VP3 of correct molecular masses were detected by SDS-PAGE and the GFP reporter gene was detected by PCR in purified rAAAV-GFP virions. Chicken embryonic fibroblast (CEF) cells and CEL cell line were transduced with the recombinant virus, the GFP-positive cells were easily observed under fluorescent microscope, expression of which lasted for at least two weeks. These data demonstrate that an efficient helper virus-free packaging system has been established for generating recombinant AAAV particles for gene transfer studies in avian cells and for development of recombinant vaccines against avian diseases.

Electronic transport properties of a kind of phenylacetylene compound— (4-mercaptophenyl)-phenylacetylene are calculated by the first-principles method in the framework of density functional theory and the nonequilibrium Green's function formalism. The molecular junction shows an obvious rectifying behaviour at a bias voltage larger than 1.0 V. The rectification effect is attributed to the asymmetry of the interface contacts. Moreover, at a bias voltage larger than 2.0 V, which is not referred to in a relevant experiment [Fang L, Park J Y, Ma H, Jen A K Y and Salmeron M 2007 Langmuir 23 11522], we find a negative differential resistance phenomenon. The negative differential resistance effect may originate from the change of the delocalization degree of the molecular orbitals induced by the bias.

Photoexcitation of a neutral soliton will create a polaron and a charged soliton. According to a tight-binding model and a nonadiabatic method, we investigate the dynamical process of these two photogenerated charge carriers in an external electric field. It is found that the polaron and the soliton can pass through each other, which excludes the possibility of carrier recombination that usually occurs in existing organic solar cells. The results indicate a more efficient way to realize the optoelectric conversion by photoexciting polymer materials with soliton defects. On the other hand, it is found that solitons take on greater stability than polarons during collision.