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Tectonic events recorded during the Middle Jurassic to Late Cretaceous in the Linzhou Basin of the Lhasa Block are associated with the subduction closure process of the BangongCo - Nujiang Tethys Ocean. To constrain the subduction closure process of the BangongCo - Nujiang Tethys Ocean during this period, a detailed magnetic fabric study of five relatively continuous strata in the Linzhou Basin during the Middle Jurassic - Late Cretaceous was carried out. The results show that the Middle Jurassic Yeba Formation developed initial deformation magnetic fabric, pencil-like magnetic fabric and tensile lineation magnetic fabric; The Late Jurassic Duodigou and Linbuzong Formations developed initial deformation and pencil-like magnetic fabrics; The Early Cretaceous Tacna Formation developed strongly cleaved magnetic fabric and tensile lineation magnetic fabric with more intense deformation; The Late Cretaceous Shexing Formation developed initial deformation magnetic fabric and pencil-shaped magnetic fabric. Combining the movement of the fracture zone, the direction of the stress field and the analysis of the tectonic environment, it is concluded that the tectonic environment has undergone four processes of extension-extrusion-extension-extrusion from the Middle Jurassic Yeba Formation to the Late Cretaceous Shexing Formation. The fracture zone undergoes three main processes: clockwise dextral rotation - rotation stop – clockwise dextral rotation. There are also relatively frequent changes in the north-south direction of the extrusion stresses and plate drag forces to which they are subjected. Thus, under the continued northward subduction of the Neo-Tethys Ocean, the tectonic processes recorded in the Linzhou Basin are associated with altered subduction polarity of the BangongCo-Nujiang Tethys Ocean. The BangongCo-Nujiang Tethys Ocean shifted from southward subduction to northward subduction during the Middle Jurassic. It shifted again to southward subduction in the Early Cretaceous and eventually closed.

The excellent swimming performances of live fish motivate scientists and engineers around the world to study its swimming mechanism and develop fish-like underwater robots, namely, the biomimetic robotic fishes. This paper compares different designs of biomimetic robotic fishes performing Body and/or Caudal Fin (BCF) swimming locomotion, and stresses how the designs evolve. The general trend is to utilize a simpler and more robust mechanism to make biomimetic robotic fishes mimic their counterparts in nature better, at the same time, to exhibit better swimming performances. Representative studies are given and discussed. Challenges of current studies are summarized and future research directions are presented. With state-of-the-art engineering and biological technologies, the biomimetic robotic fishes have great potentials in some areas where the conventional screw propellers are not applicable, like narrow space navigation and eco-friendly environment monitoring.

A novel signal-on portable sensing system has been developed for OTA detection using personal glucose meter (PGM) as signal transducer. In the study, we explore the potential of using a short dsDNA as template to trigger the “click” ligation of two DNA strands, further improve the stability of DNA strand on the magnetic beads (MBs) surface, and thereby reduce the background signal. Compared with no “click” ligation, the background signal decreases 7.5 times. Both the sensitivity and selectivity are greatly promoted. A high sensitivity with OTA detection down to 72 pg/mL is achieved, which is comparable with several existing detectors, such as fluorescence-based detectors and electrochemical detectors. The feasibility of the strategy in real samples is well verified and evaluated by detecting OTA in feed samples, indicating the potential application in the food safety field.

A triazole-stabilized fluorescence sensor is developed for copper detection in the study. Tris-(benzyltriazolylmethyl)amine (TBTA) is used to improve the sensitivity and stability for the sensing system. A series of comparative experiments are performed with and without TBTA. In the presence of TBTA, the fluorescence decrease ratio is enhanced from 2.46 to 118.25; the detection limit is reduced from 67 nM to 3.6 nM; the higher selectivity toward copper compared to the other metal ions is verified, including K+, Ca2+, Cd2+, Zn2+, Mg2+, Mn2+, Pb2+, Hg2+, Fe3+ and Cr3+. Besides, the sensing system is successfully applied for copper determination in complex tea samples and chicken feed samples with the recovery range of 91.67–116.8%. A good consistency between the presented sensor and the flame atom absorbance spectrometry (FAAS) is confirmed by the low relative errors with the range from −2.39% to 7.02%.

BACKGROUND This study aimed to identify the cultivable bacteria inhabiting the intestinal tract of adult oriental fruit flies (Bactrocera dorsalis) from laboratory-reared, laboratory sterile sugar-reared, and field-collected populations, and to evaluate the attractiveness of the metabolites produced by the above bacteria to their hosts. RESULTS Fifteen bacterial isolates chosen from the three populations were determined at species level. These 15 strains were cultured and the attractiveness of the whole Luria–Bertani broth, filtered and autoclaved supernatants to B. dorsalis adults was determined using bioassays. The bioassays showed that all bacterial strains were significantly more attractive to B. dorsalis adults than the media-only control. Among them, Bacillus cereus, Enterococcus faecalis, Enterobacter cloacae and Citrobacter freundii were the most attractive bacteria. Furthermore, results of a subsequent field test showed that the six bacterial strains were significantly more attractive than the control, with B. cereus and E. faecalis attracting significantly more flies. CONCLUSIONS A cultivable bacterial community composed of Enterobacteriaceae, Enterococcaceae, and Bacillaceae was identified in the intestinal tract of B. dorsalis. Metabolites from B. cereus attracted the greatest number of B. dorsalis adults in the laboratory and field. These results provide useful information for the development of bacterial biocontrol agents or implementation as an insecticide. © 2013 Society of Chemical Industry

Tannase (Tan410) from a soil metagenomic library was immobilized on different supports, including mesoporous silica SBA-15, chitosan, calcium alginate, and amberlite IRC 50. Entrapment in calcium alginate beads was comparatively found to be the best method and was further characterized. The optimum pH of the immobilized Tan410 was shifted toward neutrality compared with the free enzyme (from pH 6.4 to pH 7.0). The optimum temperature was determined to be 45°C for the immobilized enzyme and 30°C for the free enzyme, respectively. The immobilized enzyme had no loss of activity after 10 cycles, and retained more than 90% of its original activity after storage for 30 days. After immobilization, the enzyme activity was only slightly affected by Hg(2+), which completely inhibited the activity of the free enzyme. The immobilized tannase was used to remove 80% of tannins from a green tea infusion on the first treatment. The beads were used for six successive runs resulting in overall hydrolysis of 56% of the tannins.

The radiated silver acidum pipemedicum skin (RSAPS) was made of 0.4–0.8 mm laminal skin from healthy white pig, which was infiltrated in norfloxacin and silver nitrate, packed with the film bag of alummium poil and radiated by cobalt-60γ-ray for sterilization at the dosage of 27.92–35.31GY/min for a total dose of 25KGY. RSAPS was very effective in sterilization and had no bad effect on elasticity, adhesion, water permeability, and structure of pig skin. So it is highly appreciated by the patients and medical personnel for its convenience of usage and has gained good social and economic beneficial results.