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The effect of the substrate surface roughness on tribological properties of MoS2/Ti films, and the friction and wear mechanism was studied. MoS2/Ti films were deposited on bearing steel with different surface roughness by magnetron sputtering. The adhesion strength between the film and substrate, phase composition, surface morphology and surface roughness of MoS2/Ti films were obtained respectively by scratch tester, X-ray diffractometer(XRD), scanning electron microscope (SEM) and roughness profiler. And the tribological properties of MoS2/Ti films under dry friction, solid-oil composite lubrication and solid-grease composite lubrication were studied by a ball-on-disk tribometer. The results show that with the increase of the substrate surface roughness, the surface roughness of MoS2/Ti films increases, the intensity of (002)MoS2 and (100)MoS2 diffraction peaks first decreases and then increases, and the adhesion strength between the film and substrate decreases. When the surface roughness of the substrate is 0.01 μm, the MoS2/Ti films have good lubrication characteristics under dry friction condition. The average friction coefficient is 0.101, and the wear scar is shallow and small. With the increase of substrate roughness, the average friction coefficient and the wear rate of the samples increase first and then decrease. Meanwhile, the main wear mechanism of the film changes from abrasive wear to chip formation and fragmentation. And the effect of intermolecular interaction is greater than that of mechanical engagement, when the substrate roughness of the samples is large (Ra=0.26 μm). Under the condition of solid-oil composite lubrication, there is no fragmentation phenomenon on the worn surface with large substrate roughness. The wear scar is shallow, and the average friction coefficient is reduced by about 19%. Under the condition of solid-grease composite lubrication, the tribological properties of the samples are poor, and the effect of the substrate surface roughness on the friction coefficient is not significant.

Rationale: Spirometry reference equations that are derived from a large, nationally representative general population are warranted in China, and the impact of using prebronchodilator (pre-BD) and post-BD spirometry reference values has yet to be assessed in Chinese populations. Objectives: To present the pre-BD and post-BD spirometry reference values for Chinese adults using the China Pulmonary Health (CPH) Study. Methods: A reference population of 17,969 healthy, nonsmoking participants in the CPH Study was used to calculate the pre- and post-BD reference values for FEV1, FVC, and FEV1/FVC ratio. Pre- and post-BD reference values were applied to the entire CPH population (N = 50,991) to illustrate the divergence between the use of different references in determining disease prevalence and severity grading. Measurements and Main Results: The prevalences of airflow limitation were 5.36% using the pre-BD reference and 8.02% using the post-BD reference. Individuals who had a post-BD FEV1/FVC ratio lower than the post-BD reference value but higher than the pre-BD reference value were found to have significantly higher rates of self-reported respiratory symptoms and significantly lower values on spirometry indicators than those whose post-BD FEV1/FVC ratio was greater than the post-BD reference value. An additional 3.51% of participants were identified as having grade II–IV chronic obstructive pulmonary disease using the post-BD FEV1 predicted values. Conclusions: This study generated and applied pre- and post-BD spirometry reference values in a nationally representative Chinese adult population. Post-BD reference values may serve as an additional criterion in identifying individuals at risk for obstructive pulmonary diseases, and their diagnostic and prognostic values should be further investigated. [ABSTRACT FROM AUTHOR]

Winter rapeseed (Brassica rapa) has a good chilling and freezing tolerance. inducer of CBF expression 1 (ICE1) plays a crucial role in cold signaling in plants; however, its role in Brassica rapa remains unclear. In this study, we identified 41 ICE1 homologous genes from six widely cultivated Brassica species. These genes exhibited high conservation, with evolutionary complexity between diploid and allotetraploid species. Cold stress induced ICE1 homolog expression, with differences between strongly and weakly cold-tolerant varieties. Two novel ICE1 paralogs, BrICE1 and BrICE2, were cloned from Brassica rapa Longyou 6. Subcellular localization assays showed that they localized to the nucleus, and low temperature did not affect their nuclear localization. The overexpression of BrICE1 and BrICE2 increased cold tolerance in transgenic Arabidopsis and enhanced reactive oxygen species' (ROS) scavenging ability. Furthermore, our data demonstrate that overexpression of BrICE1 and BrICE2 inhibited root growth in Arabidopsis, and low temperatures could induce the degradation of BrICE1 and BrICE2 via the 26S-proteasome pathway. In summary, ICE1 homologous genes exhibit complex evolutionary relationships in Brassica species and are involved in the C-repeat/DREB binding factor (CBF) pathway and ROS scavenging mechanism in response to cold stress; these regulating mechanisms might also be responsible for balancing the development and cold defense of Brassica rapa. [ABSTRACT FROM AUTHOR]

Aiming at the problem of poor bearing capacity in the direction of decoupled DOF of weakly coupled three-translation parallel mechanism, a class of new configurations of large load-bearing capacity weakly coupled three-translation parallel mechanisms with closed-loop unit has been proposed in this paper. Based on the screw theory, configuration evolution method, and graphical approach method, the synthesis method of these kinds of mechanisms has been proposed, and the decoupled criterion of this mechanism and the addition conditions of the kinematic pair diagram are given. The synthesis process has been developed to synthesize the single degree of freedom translational decoupled branch chain and 2T coupled branch chain. To better apply the weakly coupled mechanism to large load occasions, a closed-loop unit construction method has been proposed. Based on the theory of singular value decomposition, a theoretical formula for increasing the load-bearing capacity of a mechanism by constructing a closed-loop unit with redundant drives has been derived for the first time. The closed-loop unit is added to the 2T coupled branch chain and the single DOF decoupled branch chain to construct the large load-bearing capacity single DOF decoupled three-translation parallel mechanism. Kinematic analysis and static analysis have been carried out on the synthesized mechanism. The Jacobian matrix of the synthesized mechanism is a block diagonal matrix, and the bearing capacity is significantly stronger than that of the decoupled mechanism, even higher than that of the coupled parallel mechanism. The synthesized weak coupling three translation parallel mechanism with large load bearing characteristics has a good application prospect in the field of high precision and large load bearing. [ABSTRACT FROM AUTHOR]

To boost the enzymatic hydrolysis of CuCl2-catalyzed organosolv pretreated sugarcane bagasse, the single and composite additives were introduced to decrease the negative influence of residual lignin. By adding the optimal loadings of composite additives (e.g., 30 mg Tween 80, 40 mg tea saponin, 40 mg bovine serum albumin (BSA), and 0.8 mg xylanase based on per g substrate), the highest glucose yield reached 96.5% after hydrolysis for 48 h. Furthermore, the composite additives were introduced to high-solids enzymatic hydrolysis, and the partial supplement of the pretreated substrate and enzyme increased the highest glucose concentration to 194.3 g/L (including 10.8 g/L oligomer glucose), accounting for 88.8% of total fermentable sugars (218.9 g/L). This fed-batch mode along with the composite additives provided a beneficial approach for high-solids enzymatic hydrolysis, the high proportion of glucose was also convenient for commercial bioethanol production using industrial bacterial strains. [ABSTRACT FROM AUTHOR]

BACKGROUND: Cells adherence provides specific information about physiology and pathology, the adhesion measurement between living cells and nanostructures can be measured by atomic force microscopy, but this detection technique is difficult to operate and costly. The adhesion height and effective contact area between cells and substrates are also the key factors affecting measurement value of the overall impedance. These factors change with structural parameters of the substrates, so the adhesion measurement between living cells and substrate can be indirectly reflected by the impedance value. OBJECTIVE: To establish a mapping relationship between the impedance measurement and the adhesion measurement of living cells. The possibility of dynamic measurement of adhesion is realized by this method, and the experimental process is simplified. METHODS: Laser interference technology was used to prepare nanoarray structures with different periods on the surface of silicon wafers for cells culture. Under the same experimental conditions, the impedance of living cells on the substrates of different cycle sizes were measured. The adhesion between cells and different substrates were analyzed by measuring impedance after the interaction between cells and substrate. RESULTS: The adhesion of living cells on the substrates of different sizes be analyzed, and the mapping relationship between the impedance and the adhesion measurement was established. The results showed that, the larger the impedance value between cells and substrate, the larger the effective contact area and the smaller the gap between them. CONCLUSION: The difference of adhesion height and effective adhesion area between living cells and substrates were obtained. This paper, a new method to measure the adhesion properties of living cells is presented, which provides theoretical basis for the related research. [ABSTRACT FROM AUTHOR]