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The high-pressure behaviors of SmFeO3 are investigated by angle-dispersive synchrotron X-ray powder diffraction under a pressure of up to 40.3 GPa at room temperature. The crystal structure of SmFeO3 remains stable at up to the highest pressure. The different pressure coefficients of the normalized axial compressibility are obtained to be βa = 0.60 × 10−3 GPa−1, βb = 0.79 × 10m3 GPa−1, βc = 1.28 × 10−3 GPa−1, and the bulk modulus (B0) is determined to be 293(3) GPa by fitting the pressure-volume data using the Birch—Murnaghan equation of state. Furthermore, the larger compressibility of the FeO6 octahedra suggests the evolution of the orthorhombic structure towards higher symmetry configuration at high pressures. [ABSTRACT FROM AUTHOR]

The article presents a study which showed a route to in situ detection of diffusion dynamics in polymer micro-objects by means of optical whispering-gallery mode (WGM) resonances. Topics discussed include characterization of WGM resonances of single microspheres using a confocal microscopic photoluminescence (PL) system, an overview of the full process covering four stages, and sample preparation.

The article discusses about the application of patterning in nanofabrication and nanomaterials assembly, with demonstrated prospects in the fabrication of nano/molecular-scale devices. It mentions the results of the study confirm the robustness of the bubble template to prepare molecular-scale patterns, verify the criticality of molecular symmetry to obtain the ultimate precision.

An adaptive wheel-legged shape reconfigurable mobile robot, based on a scissor-like mechanism, is proposed for an obstacle detecting and surmounting robot, moving on complex terrain. The robot can dynamically adjust its own shape, according to the environment, realizing a transformation of wheel shape into leg shape and vice versa. Each wheel-legged mechanism has one degree of freedom, which means that only the relative motion of the inner and outer discs is needed to achieve the transformation of the shape into a wheel or a leg. First, the force analysis of the conversion process of the wheel-legged mechanism is carried out, while the relationship between the driving torque and the friction factor in the non-conversion trigger stage and in the conversion trigger stage is obtained. The results showed that the shape conversion can be better realized by increasing the friction factor of the trigger point. Next, the kinematics analysis of the robot, including climbing the obstacles, stairs and gully, is carried out. The motion of the spokes tip is obtained, in order to derive the folding ratio and the surmountable obstacle height of the wheel-legged mechanism. The parameters of the wheel-legged structure are optimized, to obtain better stability and obstacle climbing ability. Finally, a dynamic simulation model is established by ADAMS, to verify the obstacle climbing performance and gait rationality of the robot, in addition to a prototype experiment. The results showed that the surmountable obstacle height of the robot is about 3.05 times the spoke radius. The robot has the stability of a traditional wheel mechanism and the obstacle surmount performance of a leg mechanism, making it more suitable for field reconnaissance and exploration missions.

Objective To investigate the effect of Helicobacter pylori-400 that was isolated from high incidence area of gastric cancer on the proteome of gastric epithelial cell line GES1. Methods The gastric mucosa of patients with positive C-13 breath test was sampled with gastroscope, and H.pylori was isolated. GES1 was co-cultured with H.pylori-400 in the ratio of 1∶50, cellular RNA was extracted,and the mRNA expressions of IL-8, IL-1β and TNF-α were detected by RT-qPCR. Cellular proteins were extracted and analyzed by HPLC-MS, lable-free was used for quantitative analysis. The differentially expressed proteins were selected for enrichment analysis of GO and KEGG, and the hub genes were screened out for further analysis. Results H.pylori-400 promoted mRNA expres- sion of IL-8, IL-1β and TNF-α of gastric epithelial cells. HPLC-MS showed that 373 proteins molecules changed(|Fold change|≥2) after GES1 co-cultured with H.pylori-400, among them, 143 proteins molecules decreased and 230 protein molecules increased. GO and KEGG enrichment analysis showed that H.pylori-400 regulated the secretion of inflammatory factors by regulating cell cycle, T cell immune activity and p53 pathway, which may lead to tumor genesis. Conclusions H.pylori-400 isolated from the high incidence area of gastric cancer can promote the expression of inflammatory factors and promote the tumor genesis by affecting the proteome of GES1 cells.

Abstract Batch experiments were designed to ascertain the morphology and valence of chromium in the reduction of hexavalent chromium with syrup under different pH conditions. Results indicated that the syrup reduced hexavalent chromium to trivalent chromium, and the existing forms of Cr were mainly Cr(OH)3, CrOOH and CrOOH–Fe. The percentage of Fe–Mn oxide-bound state was 29.28%, 29.28%, 22.22% and 20.12%, respectively, and the percentage of organic binding state was 64.71%, 66.58%, 74.74% and 73.14%, respectively, in the reaction systems at different pH (2.0, 2.5, 3.0 5.6) conditions.

The article offers information on a study which examined asymmetric photon transport and directional light propagation in single-crystal organic semiconductor nanowires using electrically controlled exciton diffusion. A physical vapor transport technique was used to obtain 9,10-bis(phenylethynyl)anthracene (BPEA) nanowire crystals. It shows that electrotunable asymmetric optical outcoupling was accomplished by modifying direction and field strength.

The article reports on using miniaturized lasers with multicolor output and high spectral purity to obtain more compact and more versatile photonic devices. It presents a strategy to realize dual-color single-mode lasing in axially coupled cavities. Dual-color single-mode lasing was achieved in the axially coupled heterogeneous nanowire resonators.

Objective: To investigate the clinical effects of spinal canal decompression and pedicle screw reduction and fixation, and intervertebral bone grafting fusion for the treatment of lumbar spondylolisthesis associated with nerve compression symptoms., Methods: Postlaminectomy vertebral lamina reconstruction and pedicle screw reduction and fixation were performed in 32 patients with lumbar spondylolisthesis between August 2007 and August 2008. Of them, 26 patients were followed up for more than 1 year, including 16 males and 10 females who ranged in age from 55 to 76 years (mean 62.5 years). The course of disease was 2-10 years. All patients had low back pain, numbness and pain in one or both lower extremities and intermittent claudication symptoms. Radiograms showed L3, L4 or L5 anter-olisthesis of I to III degree. There were 18 cases of regressive olisthesis and 8 cases of spondylolysis. The clinical improvement, the vertebral reduction, the lamina fusion rate and canal stenosis state were observed and assessed., Results: The wounds healed well in all 26 cases without occurrence of significant complications. Clinical improvement was assessed according to the JOA lower back pain score scale. The mean preoperative score was 5.2 +/- 1.5, and 23.1 +/- 1.9 at 3 months after operation. The result was excellent in 20 cases, good in 5 cases, and fair in 1 case. The mean score on the last followed-up was 22.9 +/- 2.4, and the result was excellent in 19 cases, good in 5 cases, and fair in 2 cases. JOA score at 3 months after operation and that at the last followed-up were significantly different from that before operation (P = 0.00), and there was no significant difference between JOA score at 3 months after operation and that at the last followed-up (P > 0.05). Complete reduction was achieved in 17 degree I case and 5 degree II cases. Two degree II cases were improved to degree I, and 2 degree III cases were improved to degree I. Vertebral fusion was achieved 3 months after operation in 20 cases, and in all cases at the last followed-up. CT examination at the last follow-up showed no stenosis of the vertebral canal, dural sac and nerve root compression. The rebuilt vertebral lamina fused well. No graft bone absorption or failing fixation occurred., Conclusion: Postlaminectomy reconstruction of the vertebral lamina and pedicle screw reduction and fixation can achieve satisfactory reduction and spine biomechanical stability in the treatment of lumbar spondylolisthesis, and can prevent latrogenic stenosis of the vertebral canal due to nerve oppression by the postoperative scar and nerve adhesion, with good early and medium-term curative effects. In addition, it provides a new way of thinking in the treatment of lumbar spondylolis-thesis.