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This work investigated the effect of nanodiamond (ND) additives on the tribological properties of CrN-coated piston ring mating with the chromium-plated and BP alloy iron cylinder liners, which is one of the key friction pairs in the internal combustion engines. To enhance the dispersion of the NDs in the base oil, the surface of ND particles was modified with polyaniline via in situ polymerization. The friction and wear as well as the scuffing characteristics of the friction pair lubricated with different contents of ND composite-added base oil were evaluated by using the reciprocating tribotests, which are close to the actual conditions. The wear surface morphologies and elements distribution were analyzed to explore the wear behaviors and the associated mechanisms of friction pairs under the lubrication incorporated with the ND composites. The results show that the ND additive is beneficial for the pair of Cr liner and CrN-coated piston ring in the friction and wear as well as scuffing properties, and the best concentration of ND additive is expected to be around 1 wt%. But for the BP liner, the developed nanocomposite has a negative impact. The friction force and the wear loss of the pair lubricated by the ND composite-added oil are even worse than that tested with the base lubricating oil.

The methanol to olefins (MTO) process has received considerable interest due to its importance in transforming abundant resources such as coal, natural gas, and biomass to widely‐demanded light olefins. In the MTO process, the coke deposited on the catalyst governs the catalyst activity and product selectivity, and thus is critical to the reaction behaviour. In the industrial processes, the residence time and coke content of catalyst particles in the reactor show a certain distribution due to the continuous outflow of spent catalyst and inflow of regenerated catalyst, which need further attention. The multi‐phase particle‐in‐cell (MP‐PIC) approach was used in the current work to simulate the catalyst residence time and coke content distribution. The effect of gas‐solid flow patterns, reactor structure, and average catalyst residence time on the residence time and coke content distribution was investigated. It was found that at high superficial velocities, the coke content distributions obtained with the MP‐PIC method are consistent with the distribution deduced from the ideally mixed flow assumption of catalyst particles. The results suggested that it is possible to simulate large‐scale MTO reactors by use of the coke distribution. In particular, by incorporating an initial coke distribution, the time needed to reach steady state in the MTO reactor simulations could be greatly reduced. [ABSTRACT FROM AUTHOR]

Background: Accurate clinical staging of non-small cell lung cancer (NSCLC) is essential for developing an optimal treatment strategy. This study aimed to determine the predictive risk factors for lymph node metastasis, including both N1 and N2 metastases, in clinical T1aN0 NSCLC patients., Methods: We retrospectively evaluated clinical T1aN0M0 NSCLC patients who showed no radiologic evidence of lymph node metastasis, and who had undergone surgical pulmonary resection with systematic mediastinal node dissection or sampling at the First Affiliated Hospital of Zhejiang University between January 2011 and June 2013. Univariate and multivariate logistic regression analyses were performed to identify predictive factors for node metastasis., Results: Pathologically positive lymph nodes were found in 16.2% (51/315) of the patients. Positive N1 nodes were found in 12.4% (39/315) of the patients, and positive N2 nodes were identified in 13.0% (41/315) of the patients. Some 9.2% (29/315) of the patients had both positive N1 and N2 nodes, and 3.8% (12/315) of the patients had nodal skip metastasis. Variables of preoperative radiographic tumor size, non-upper lobe located tumors, high carcinoembryonic antigen (CEA) levels and micropapillary predominant adenocarcinoma (AC) were identified as predictors for positive N1 or N2 node multivariate analysis., Conclusions: Pathologically positive lymph nodes were common in small size NSCLC patients with clinical negative lymph nodes. Therefore, preoperative staging should be performed more thoroughly to increase accuracy, especially for patients who have the larger size, non-upper lobe located, high CEA level or micropapillary predominant ACs.

Telomerase Cajal body protein 1 (TCAB1) is a telomerase holoenzyme, which is markedly enriched in Cajal bodies (CBs) and facilitates the recruitment of telomerase to CBs in the S phase of the cell cycle. This recruitment is dependent on TCAB1 binding to a telomerase RNA component. The majority of cancer cells are able to grow indefinitely due to telomerase and its mechanism of trafficking to telomeres. In the present study, a certain level of TCAB1 expression in A549 human lung cells was identified and TCAB1 knockdown exhibited a potent antiproliferative effect on these cells, which was coupled with a decrease in the cell density and activity of the cellular enzymes. In addition, TCAB1-depletion was demonstrated to inhibit telomerase trafficking to telomeres in the A549 cells, leading to subsequent G 1 cell cycle arrest without inducing apoptotic cell death. Overall, these observations indicated that TCAB1 may be essential for A549 cell proliferation and cell cycle regulation, and may be a potential candidate for the development of a therapeutic target for lung adenocarcinomas.