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This study aimed to compare the efficacy between decompression and drainage seton (DADS) and cutting seton (CS) in the treatment of high complex anal fistula. Patients were randomly assigned 1:1 to DADS or CS group. The primary outcome was the rate of wound healing. Second outcomes included time taken to return to work, postoperative pain, the severity of fecal incontinence and other complications. A total of 120 patients with a mean age of 39 years were included. There was no significant difference in the rate of complete wound healing at 1 year. The mean time taken to return to work was 5 ± 2 days in DADS group, shorter than CS group (10 ± 3, p

Integrating carbonaceous materials onto nano-scaled porous metal oxides to form shell-core-shell hollow structure has good prospects in the development of high-performance electrode materials for Li-ion battery, but it still remains challenging. Herein, with Fe3O4 hollow nanospheres as partial self-templates, we construct sandwich-like double nitrogen-doped C-shelled porous Fe3O4 hollow spheres by pyrolyzing polypyrrole (PPY) which is in situ polymerized on the interior and the exterior shells of Fe3O4 hollow spheres. And the polymerization time of PPY have important influence on thickness of carbon layer in the composites and further change their electrochemical performance. The shell-core-shell hollow structure offers highly contact between carbon and porous Fe3O4 and provides amount of volume stress buffer nanospaces during electrochemical processes, which promotes electron transport effectively and keeps good structural stability. The obtained sandwich-like double N-doped C-shelled porous Fe3O4 hollow spheres (C N@Fe3O4@C N HSs) are prepared as Li-ion battery anode and show an ultrahigh reversible specific capacity, high rate capability, remarkable cycle stability, excellent capacity retention (high capacity of 1048 mA h g−1 after 300 cycles at 0.1 A g−1, which is about 99.1% of the capacity in the 2nd cycle) and high coulombic efficiency (about 99% over 300 cycles). This research shows great potential of the sandwich-like shell-core-shell hollow structure in Li-ion batteries.

Zearalenone (ZEN) and its derivatives are non-steroidal estrogenic mycotoxins mainly produced by Fusarium species. They are widely distributed in grain feeds originated from maize, barley, wheat and sorghum, causing serious harm to animal and human health. Currently, there is a pressing need of an efficient technology for ZEN degradation and detoxification. Because traditional physical and chemical methods could not effectively detoxify ZEN in grains, and might also affect the grain nutrients and food taste, and even result in secondary pollution, the biological technologies are developed to detoxify ZEN and its derivatives. In this paper, we reviewed the structure of ZEN and its derivatives, the fungi and bacteria species with ability of degradation of ZEN. In addition, the characterization, protein sequences and conformation of currently identified ZEN degrading enzymes, the only solved ZHD structure from Clonostachys rose were analyzed and compared, and the enzymes heterologous expression and application were also reviewed. This review will provide reference for reducing the cost of ZEN degrading enzymes by biological technologies such as enzyme engineering and fermentation engineering.玉米赤霉烯酮 (Zearalenone，ZEN) 及衍生物是一类主要由镰刀菌属的真菌产生的非甾体雌激素类真菌毒素，广泛存在于玉米、大麦、小麦和高粱等谷物饲料及其副产品中，严重危害牲畜及人类健康，迫切需要相关的技术对ZEN 进行降解脱毒。传统的物理化学方法不能有效去除谷物中的毒素，并会破坏谷物的营养成分，影响食物口感，甚至造成二次污染，因此利用生物工程技术对ZEN 及其衍生物进行脱毒是未来解决这一问题的主要方法。文中简要介绍了ZEN 及衍生物和降解ZEN 的微生物种类、降解特性，然后详细介绍了目前研究的ZEN降解酶种类、解析唯一的蛋白结构及其异源表达和应用情况，以期为通过分子酶工程和发酵工程等生物工程技术降低ZEN 降解酶的成本提供指导，从而提高食品安全。.

A facile hydrothermal method was employed to synthesize porous α-Fe 2 O 3 @SnO 2 heterostructure nanotubes. The morphologies and structures of the as-prepared samples were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), and N 2 adsorption–desorption techniques. The hollow α-Fe 2 O 3 nanotubes with outer diameters of about 90 nm were uniformly coated by a 10 nm thick layer of SnO 2 nanoparticles, demonstrating apparent heterostructures. The α-Fe 2 O 3 @SnO 2 heterostructure nanotubes were applied to construct gas-sensor devices which exhibited high sensitivity, fast response–recovery, good selectivity and excellent repeatability to acetone. Because of the porous structure and large specific surface area, the heterogeneous core–shell nanocomposites show a markedly enhanced gas sensing performance in comparison with the initial α-Fe 2 O 3 nanotubes and the pure SnO 2 nanoparticles. For example, the sensitivity of the α-Fe 2 O 3 @SnO 2 composites to 100 ppm acetone can reach as high as 33.4 at the optimum operating temperature of 300 °C, which was about twice of the value for pure α-Fe 2 O 3 nanotubes and even up to 5-fold higher than that of pure SnO 2 nanoparticles.

A novel method was developed to design highly sensitive ethanol gas sensor based on the mechanism of ethanol quasi molecular imprinting. SnO 2 nanoparticles E and W were prepared by incorporating liquid ethanol which is the tested objective gas with deionized water thermal method and pure deionized water thermal method respectively. SnO 2 nanoparticle films WW and EW for ethanol gas sensor were obtained by mixing pure deionized water with the as-prepared powders W and E, and WE and EE were prepared by mixing liquid ethanol with W and E powders respectively. The ethanol gas sensing properties of these films were evaluated. Testing results reveal that the sensor S EE based on film EE which was fabricated by mixing liquid ethanol with E nanoparticles exhibits the most excellent sensing performance to ethanol gas and the response descended in the order of S WE , S EW and S WW . It proves that the introduced objective gas in the procedure of device fabrication plays a very important role for design a highly sensitive gas sensor. In addition, we consider that pore diameter of about 4.3 nm may be the critical size for the smooth adsorption and desorption of ethanol gas.

This work presents a new route to design a highly sensitive SnO2–based sensor for acetone gas enhanced by the molecular imprinting technique. Unassisted and acetone-assisted thermal synthesis methods are used to synthesis SnO2 nanomaterials. The prepared SnO2 nanomaterials have been characterized by X-ray powder diffraction, scanning electron microscopy and N2 adsorption−desorption. Four types of SnO2 films were obtained by mixing pure deionized water and liquid acetone with the two types of as-prepared powders, respectively. The acetone gas sensing properties of sensors coated by these films were evaluated. Testing results reveal that the sensor coated by the film fabricated by mixing liquid acetone with the SnO2 nanomaterial synthesized by the acetone-assisted thermal method exhibits the best acetone gas sensing performance. The sensor is optimized for the smooth adsorption and desorption of acetone gas thanks to the participation of acetone both in the procedure of synthesis of the SnO2 nanomaterial and the device fabrication, which results in a distinct response–recovery behavior.

This paper presents a technique to diagnose the three-dimensional temperature fields of arc plasma with orthographic and double-wave spectral tomography. First, the system with two orthographic directional CCD image real-time cameras is adopted to get the information of spectrum intensity related to the gray scale of arc plasma. Second, the improved computerized tomography iterative technique which accords with the least-square and max-entropy criterions, simultaneously, has been used to reconstruct the distributions of different emission coefficients, which shows superiority to the conventional tomography algorithms. Finally, based on plasma physical theory, the spectrum relative-intensity method has been used to reconstruct the distribution features of three-dimensional temperature fields. The experimental results have shown the effectiveness of this measurement system with high-precision and real-time ability. (C) 2009 Elsevier Ltd. All rights reserved.

For reconstructing based on incomplete projection data, an improved max-entropy reconstruction algorithm is presented in this paper. Both least-square and max-entropy are used in this algorithm, and the penalize-function method is used in iterative processing. The numerical simulation of three different tested fields has been done. Compared with conventional three-dimensional reconstruction algorithms, this novel algorithm has a higher reconstruction precision as well as a better astringency, particularly in the case of easy tested field. For the reconstruction of asymmetric complicated tested field, it also has a good result if suitable projective direction and iterative times can be choosen. Finally, the application of this novel algorithm to diagnose the temperature field of arc plasma is presented.