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Ni‐based catalysts for dry reforming of methane (DRM) are prone to suffer from deactivation caused by carbon deposition and sintering. Pyrochlore (typically A2B2O7) is a thermostable material with substantial redox capacity, which makes it suitable as a support for Ni‐based DRM catalysts. Here we demonstrated that by adjusting the Zr/Ce ratio in the B‐site of the La2(CeZrNi)2O7 (10 wt.% Ni loading), its structural order could be significantly altered. With decreasing Zr/Ce ratio, the structure of the catalysts became less ordered with a phase transformation from pyrochlore (La2Zr2O7) to defective fluorite (La2Ce2O7). Meanwhile, a second phase La2NiZrO6/LaNiO3 other than pyrochlore was formed for each sample. By tuning the structure, samples presented different properties and XPS results illustrated that the compositions of the surface oxygen species of samples were significantly different. Catalysts possessing more oxygen vacancies displayed evidently enhanced coke resistance. Among all five catalysts, LNZ3C1 exhibited the highest activity, stability and carbon deposition resistance, which could be attributed to the most oxygen vacancies, the strongest nickel‐carrier interaction, and the best particle size distribution of it. [ABSTRACT FROM AUTHOR]

Abstract Background Japanese encephalitis virus (JEV), as a re-emerging virus that causes 10,000-15,000 human deaths from encephalitis in the world each year, has had a significant impact on public health. Pigs are the natural reservoirs of JEV and play an important role in the amplification, dispersal and epidemiology of JEV. The nonstructural protein 3 (NS3) of JEV possesses enzymatic activities of serine protease, helicase and nucleoside 5'-triphosphatase, and plays important roles in viral replication and pathogenesis. Results We characterized the NS3 protein of a neurovirulent strain of JEV (SH-JEV01) isolated from a field-infected pig. The NS3 gene of the JEV SH-JEV01 strain is 1857 bp in length and encodes protein of approximately 72 kDa with 99% amino acid sequence identity to that of the representative immunotype strain JaGAr 01. The NS3 protein was detectable 12 h post-infection in a mouse neuroblastoma cell line, Neuro-2a, and was distributed in the cytoplasm of cells infected with the SH-JEV01 strain of JEV. In the brain of mice infected with the SH-JEV01 strain of JEV, NS3 was detected in the cytoplasm of neuronal cells, including pyramidal neurons of the cerebrum, granule cells, small cells and Purkinje cells of the cerebellum. Conclusions The NS3 protein of a neurovirulent strain of JEV isolated from a pig was characterized. It is an approximately 72 kDa protein and distributed in the cytoplasm of infected cells. The Purkinje cell of the cerebellum is one of the target cells of JEV infection. Our data should provide some basic information for the study of the role of NS3 in the pathogenesis of JEV and the immune response.

A series of novel zinc-polyurethane copolymers, which contained zinc cations in the form of polymeric salt and can be exchanged with the sodium ions in sea water, was prepared. As the ion exchange reaction proceeded, the zinc-polyurethane copolymers became soluble and leached out by the flow of sea water. The self-polishing rates of marine antifouling coatings formulated with the polymers proved to be easily controlled by the amount of 2,2-bis(hydroxymethyl) propionic acid. Marine field test revealed that zinc-polyurethane antifouling coatings had excellent efficiency in preventing marine biofouling for more than 12 months. These results proved that the zinc-polyurethane copolymers were a good candidate for the preparation of long-efficiency and controllable marine antifouling coatings. [ABSTRACT FROM AUTHOR]

Atherosclerosis (AS) is a serious healthy burden worldwide, it occurs accompany with the disfunction of vascular smooth muscle cells (VSMCs). MicroRNAs play pivotal role in the pathogenesis of various diseases. This study aimed to investigate the expression and clinical value of miR-199a-3p in patients with asymptomatic AS, and further explore its regulatory role on VSMCs biological function. Quantitative real-time PCR was used to estimate the expression of miR-199a-3p. Correlation of miR-199a-3p with carotid intima-media thickness (CIMT) and C-reactive protein (CRP) was evaluated by Pearson correlation coefficient. A receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic value of miR-199a-3p. Effects of miR-199a-3p on cell proliferation and migration in VSMCs were analyzed using cell-counting method and Transwell assay. Luciferase reporter assay was performed for the target gene analysis. Serum expression of miR-199a-3p was decreased in asymptomatic AS patients compared with the healthy controls. The negative correlations of miR-199a-3p with CIMT and CRP were obtained. The decreased miR-199a-3p was proved to have diagnostic accuracy with an area under the ROC curve (AUC) of 0.912, and was an independent predictor for the occurrence of asymptomatic AS. In VSMCs, overexpression of miR-199a-3p led to inhibited cell proliferation and migration, while the knockdown of miR-199a-3p resulted in the opposite results. SP1 was proved to be the target gene of miR-199a-3p. Taken together, downregulated expression of miR-199a-3p is a candidate diagnostic biomarker in the patients with asymptomatic AS. Overexpression of miR-199a-3p exists suppressive effects on VSMC proliferation and migration, indicating that miR-199a-3p may be a potential therapeutic target for AS treatment. [ABSTRACT FROM AUTHOR]

Uniaxial compressive strength is an important mechanical parameter for rock mass engineering. Hence, how to determine the UCS simply and accurately have drew numerous attention. In this paper, the references related to UCS estimation using indirect tests were reviewed, and three stages of the development of indirect UCS estimation were classified. Meanwhile, the merits and drawbacks of different kinds of indirect tests for evaluating UCS were analyzed, and a indirect parameter (Schmidt hammer rebound value (L-type)) was determined to estimate the UCS values. For establishing more precise predictive model, more than 700 groups of data set were collected from 20 references. Subsequently, the improved least squares tree algorithm was utilized to establish the predictive model. The fitting coefficients indicated that the predictive model can be applied to engineering practice. [ABSTRACT FROM AUTHOR]

Purpose: With the continuous change of research contents and methods of intelligence science, its integration with other disciplines is also deepening. The purpose of this paper is to further explore the interdisciplinary research characteristics of intelligence science in theoretical depth and application value. Design/methodology/approach: This paper summarizes and explores in two aspects. The first is a large number of literature review, mainly combined with the historical characteristics of the development of intelligence science researches in China and international comparison. The second is to refine the discipline construction ideas suitable for the development of contemporary intelligence science. Findings: From the perspective of the historical development of discipline relevance, the development characteristics and positioning of intelligence science in China are introduced, with the comparison of many disciplines including information technology, library science, information science, data science, management science and other disciplines. In order to better meet the practical needs of intelligence service in the new era, this paper mainly analyzes the construction method of intelligence science research system and the relocation of intelligence science research content. Originality/value: This paper summarizes the historical characteristics and international comparison of the development of intelligence science in China. It proposes the development characteristics and orientation of intelligence science in China from the perspective of historical development of discipline relevance. It also proposes the discipline construction ideas suitable for the development of contemporary intelligence science. [ABSTRACT FROM AUTHOR]

Under the circumstance that lower protective seam mining may give rise to mining-induced fracture development in the upper coal and rock mass, the key to gas extraction during lower protective seam mining is investigated based on mining-induced fracture development law of overlying strata. Fracture evolution processes are seldom described by the traditional "Three Zone" theory of overlying strata. Consequently, its field application in gas extraction during the lower protective seam mining is limited. While theoretical analysis and analog simulation are adopted to analyze mining-induced fracture development rules for the lower protective seam mining, a plastic hinge is selected to theoretically derive a process from internal fracture development to occurrence of rock beam fracturing. In combination with the theory of key strata that the movement of overburden is controlled by key bond strata, a computing method is obtained to figure out development height of a gas conducting fissure zone during the lower protective seam mining. Taking geological conditions in Jinjia Coal Mine as the engineering background, development height of the gas conducting fissure zone in No. 22 seam there is calculated to be 42.2 m. On this basis, engineering design is performed for pressure relief gas extraction of the lower protective seam mining. During working face mining, gas emission quantity and sources are also monitored according to gas conducting features of strata within a range of the gas conducting fissure zone. Hence, accuracy in development range computations for this zone is verified. As demonstrated by research findings, combining the plastic hinge theory with a control action of key strata has the potential to effectively work out development height of the gas conducting fissure zone during the lower protective seam mining. Without a doubt, an accurate theoretical basis can be provided for pressure relief gas extraction in the course of lower protective seam mining. [ABSTRACT FROM AUTHOR]

In order to investigate whether adjuvant chemotherapy is essential for patients with early-stage serous and endometrioid epithelial ovarian cancer, the present study collected data from the US Surveillance, Epidemiology and End Results database between 2004 and 2015. All subjects underwent comprehensive staging surgery and were diagnosed as stages IA-IIA, grade 1–2. A total of 2644 patients were enrolled in the present study, among which 1589 patients received platinum-based chemotherapy. Comparisons of categorical data were performed via χ2 tests. Variables with P < 0.05 in univariate analyses were further analyzed using multiple logistic regression. Selection bias from the heterogeneity of demographic and clinical characteristics was avoided using propensity score matching. Cox proportional hazards models were applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs), investigating the association between variables and 5-year overall survival. After the propensity score matching, there was an equal number of patients with or without chemotherapy (n = 925). The results of the present study indicated that those aged ≥65 years were at an increased risk of ovarian cancer, and the age was associated with poor prognosis (HR, 1.486; CI, 1.208–1.827; P < 0.001). Endometrioid carcinoma was associated with improved 5-year overall survival compared with serous cystadenocarcinoma (HR, 0.697; CI, 0.584–0.833; P < 0.001). Chemotherapy could not prolong the 5-year overall survival of patients with early-stage serous and endometrioid ovarian cancer (HR, 1.092; CI, 0.954–1.249; P = 0.201). These results demonstrated that adjuvant chemotherapy was unnecessary for patients with early-stage serous and endometrioid ovarian cancer after they underwent comprehensive staging surgery. [ABSTRACT FROM AUTHOR]