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On January 21, 2016, an MS6.4 earthquake occurred in Menyuan county, Qinghai province. Field investigations suggest that the long axis of the elliptical affected area is N120°-140°E. Comparative interpretations of high resolution remote sensing images before and after the shock show more than 23 sites of landslides and collapses, which are more distributed in the north of epicenter than in the south, extending in NNW overall. As the Lenglong Ling fault (LLF) is dominated by horizontal movement from high resolution remote images and field observation, it should not be responsible for this event of pure thrusting. North of the Lenglong Ling fault, there is a fault striking in 140°, which is north-dipping on the surface according to high resolution remote sensing, similar to the nodal plane I of focal mechanism solutions from deferent institutes. The long axis' direction of the overall distribution of aftershocks has also a difference of 20° with LLF, while almost parallel to the fault on its north. Thus, we infer that this fault is most likely the seismogenic structure of the Menyuan earthquake. Integrating the characteristics of aftershock distribution at depth, main shock focal mechanism solutions, geometric distribution and activity of the seismogenic fault on surface, in combination with the magnetotelluric sounding and related geophysical data around the earthquake zone, a cartoon model of the seismogenic mechanism is established. We speculate this earthquake is one of the events occurring during the pushing growth process of the Tibetan Plateau blocks in NE direction following the 2008 MS7.4 and 2014 MS7.3 earthquakes in Yutian, Xinjiang.

Two new Pb(II) coordination polymers, [PbL(bpy)]n (1) and {[PbL(bpp)]·2H2O}n (2) [L = 2,2′-(diazene-1,2-diyl)dibenzoate acid, bpy = 4,4′-bipyridine, bpp = 1,3-bis(4-pyridyl)propane], have been hydrothermally synthesized and characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. Compound 1 shows a 3-D 3-fold interpenetrating framework structure with a 66 topology. Compound 2 displays a 2-D lattice layer structure. The structural differences between 1 and 2 indicate that N-donor ancillary ligands play a key role on the final architectures. Thermal stabilities and luminescent properties of 1 and 2 in solid state were also investigated.

A new analysis method using ultra-performance liquid chromatography (UPLC)-quadrupole-time-of-flight mass spectrometry (Q/TOF MS) was developed for screening and confirmation of 12 β-agonists in feeds. Under the optimized gradient elution conditions, it takes only 6 min to separate all 12 β-agonists, and the critical pair of Ractopamine and Isoxsuprine isomers was almost completely separated. Based on the over 10,000 full-width at half maximum (FWHM) mass resolution and high mass accuracy features of TOF MS with 20 mDa mass window, accurate mass chromatograms were reconstructed for individual compounds. The fragmentation pathways of 12 β-agonists were also studied using Q-TOF MS. The potential of UPLC-Q/TOF MS for confirmatory analysis was shown by determining the accurate mass of all compounds and fragment ions upon collision-induced-dissociation (CID) at different energies. The extra mass measurement errors for all β-agonists were found to be within 5 ppm. The limits of detection (LODs) and limits of quantitation (LOQs) were determined for all β-agonists in feeds and found to be 1-5 ng/mL and 5-50 μg/kg, respectively. The method of UPLC-Q/TOF MS developed in this study was initially applied to the research of feeds for analysis of 12 β-agonists and proved to be accurate, sensitive, convenient and practical.

【Abstract】Objective: To evaluate the in vitro and in vivo osteogenic capability of adipose-derived stromal cells (ASCs). Methods: ASCs were isolated from New Zealand white rabbits and determined by alkaline phosphatase (ALP) staining, von Kossa staining and alizarin red staining. Some specific markers of osteogenic differentiation, including ALP, osteocalcin (OCN), osteopontin (OPN) were examined by reverse transcription-polymerase chain reaction (RT-PCR). In vivo, demineralized bone matrix (DBM)-ASCs composites were implanted into the rabbit calvarial defects created at each side of the longitudinal midline. After 6 weeks, histologic properties of the transplants were analyzed. Results: ASCs were successfully induced into osteogenesis. ALP staining, von Kossa staining and alizarin red staining showed positive results. The expressions of ALP, OCN and OPN were detected in ASCs after cultivation in osteogenic medium. Extensive new bone was observed in the defects transplanted with DBM-ASCs composites. Conclusion: ASCs have the potential to differentiate into osteogenic lineage and DBM-ASCs constructs are a promising method for regeneration in bone defects. Key words: Adipose tissue; Bone regeneration; Osteogenesis

【Abstract】Objective: To evaluate the preliminary clinical outcomes of coccygectomy in patients with coccydynia after a failure of conservative treatment. Methods: From May 2002 to January 2010, 31 patients with coccydynia were treated by coccygectomy in our department after conservative measures had failed to produce significant relief. A questionnaire, which included the extent of relief in the painful area, improvement in quality of life, intensity of pain in the sitting position, and pain score during daily activities, was used to evaluate the results. Results: All patients were followed up for 1 to 6 years (mean 3.3 years). The results were excellent in 20 patients (64.5%), good in 7 patients (22.6%), moderate in 3 patients (9.7%) and poor in 1 patient (3.2%). The excellent and good rates amounted to 87.1%. All patients except one had complete resolution of their symptoms and were subjectively highly satisfied with the outcomes of the surgery. Only 2 cases of superficial infection were observed postoperatively. Conclusion: Coccygectomy is a feasible management option for patients with coccygodynia that has no response to conservative treatments. Key words: Coccyx; Pain; Surgical procedures, operative

【Abstract】Objective: To evaluate the feasibility and therapeutic effect of treating sternoclavicular joint dislocation by K-wire and tension band wire fixation, and to improve the safety and stability of this technique. Methods: This study consisted of 9 cases, 6 males and 3 females with the mean age of 25 years (range, 9-62 years). The causes were traffic accident in 7 cases, falling in 1 case and fight in 1 case. The duration from injury to operation was 2 hours to 7 days. There were 5 left dislocations and 4 right dislocations; 8 anterior dislocations and 1 posterior dislocation, including one combined with left scapular fracture and one with left olecranon fracture. Open reduction and internal fixation using K-wires and tension band wires were performed to treat dislocations. Results: All patients were followed up for 6 to 24 months, 10 months on average. According to Rockwood’s rating scale on postoperative sternoclavicular joint, 8 cases achieved excellent outcomes with an average score of 13.88, and the rest case achieved a good outcome with the score of 12. Anatomical reduction was obtained in all cases. There were no such postoperative complications as severe infection, injury to blood vessel and nerve, failure of fixation, etc. Patients were all satisfied with the anatomical reduction and functional recovery. Conclusions: The technique of K-wire and tension band wire fixation is safe, simple, effective, less invasive and has been successfully used in orthopedic surgery. It is effective in treating sternoclavicular joint dislocation though it has some disadvantages. Key words: Sternoclavicular joint; Dislocations; Bone wires; Fracture fixation, internal