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To investigate the deformation and failure behavior of a tunnel excavated in mixed strata, transparent soft rock test and numerical simulations were performed. The distribution features of displacement and failure and the evolution laws were analyzed. In this study, a transparent material for simulating mixed strata was developed. The visualization of the spatial deformation inside rock masses will improve the understanding of this process. The tests suggest that the mechanical properties of transparent soft rock are similar to those of natural rock. Experiments on the isotropic and mixed strata conditions were carried out to study the deformation rules during tunnel boring machine (TBM) excavation. The test results show that the dominant deformation position and direction exist in isotropic and mixed strata. A shear slip band occurs in both mixed and isotropic strata but with different distributions. Finally, numerical simulations were conducted to study the failure process, and the damage pattern of the transparent soft rock experiment was similar to that of the numerical simulation. The interface of the softness and hardness layers controls the extension of rock damage.

A series of modified polysaccharide microparticles have been fabricated and their potential application for scavenging reactive oxygen species (ROS) and their derivatives to achieve osteoarthritis (OA) treatment has been explored. These microparticles were cross-linked dextran (Sephadex) with different carbazate substitution ratios determined by the TNBS assay and elemental analysis. It has been demonstrated that they could effectively scavenge carbonylated proteins and ROS including hydroxyl radicals (˙OH), superoxide anions (˙O2-) and H2O2 and their derivatives with high efficiency, improve the viability of H2O2-treated chondrocytes by reducing their ROS levels, as well as lower their inflammatory factors. The above ability of antioxidation and inflammation resistance improved with the increase of carbazate substitution ratio. Significantly, this work provided the proof that modified Sephadex successfully alleviated the deterioration of cartilage and the progression of OA in vivo. The proposed microparticles showed a very promising capability for reducing ROS levels and further treating OA.

To select elite germplasms, 112 mutants derived from japonica rice cultivar Wuyujing 3 were evaluated. The yield components such as panicle number per square meter, grain number per panicle, and grain weight were measured. The quality traits such as percentage of chalky grains (PCG), brown rice yield (BRY), milled rice yield (MRY), degree of milling (DM), amylose content (AC), protein content (PC), and relationships among traits were inverstigated. Results showed that grain yield ranged from 2.15 to 12.49 t/hm2 with a mean of 6.4 t/hm2 and number of grains per square meter contributed for 94.64% in grain yield variation. For quality traits, all rice mutants had short size (grain length ≤ 5.5 mm) and bold shape (grain length to width ratio = 1.10–2.00). Most of rice mutants (87.5%) had PCG values below 20%. All mutants had MRY values above 50%, AC values below 20%, and PC values below 10%. Percentage of chalky grains was significantly negatively correlated with MRY and positively correlated with DM. BRY and MRY were significantly negatively correlated with DM. PC was significantly and positively correlated with MRY and negatively correlated with DM, while AC had no significant correlation with these quality traits. It was concluded that there were 25 rice mutants which fulfilled the major requirements of Jiangsu standard japonica rice such as low percentage of chalky grains, low amylose content, optimal protein content, and which could be used as elite germplasms. Thus the mutants identified may lead to significant progress in improvement of rice quality.

The paper proposes a coupling probe which can effectively expand the coupling adjustment range, and optimally designs a 64-element array antenna’s rectangular radial line feed network at the center frequency of 2.1 GHz. Simulation results show that the feed network whose caliber is 744 mm×744 mm can achieve approximately 64-road equiamplitude feed. The reflection coefficient is less than 0.1 at the center frequency, and less than 0.2 in the frequency band ranging from 2.06 GHz to 2.15 GHz.