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Singularly perturbed systems (SPSs) wildly exist in practical engineering practice; however, the disturbance rejection in SPSs is still a problem. As well-known disturbance rejection methods, composite hierarchical anti-disturbance control (CHADC) can effectively compensate and suppress disturbance, which improves the control performances of complex systems. To enhance the capability of anti-disturbance and control precision, this article proposes a novel composite hierarchical anti-disturbance (CHAD) dynamic surface control (DSC) for the fast subsystem considering highly dynamic disturbance, and CHAD proportion-integration (PI) control for the slow subsystem with slow-varying harmonic disturbance. The disturbances are supposed to be generated by an exogenous system based on partially known information with model uncertainty, and the stabilities of both fast and slow closed-loop subsystems are analyzed. Meanwhile, the compensability of disturbances is discussed. Finally, simulations for an F-8 aircraft are given to demonstrate the effectiveness of the proposed methods.

Aniline is a toxic organic pollutant and raw material in industries. In this study, the start-up of sequencing batch reactor for treating aniline wastewater was assessed and functional microbial clusters were analyzed after enrichment of denitrifying phosphate-accumulating organisms (DNPAOs). The aniline degradation and subsequent removal of NH4+-N mainly happened in aerobic condition, and denitrification was conducted in both anaerobic and anoxic conditions. Besides aerobic phosphorus uptake, phosphorus accumulation also occurred via DNPAOs in anoxic condition utilizing nitrate as electron acceptor. The removal efficiencies of COD, NH4+-N, TN, and TP was over 91.6, 67.1, 65.0, and 79.9% respectively. Proteobacteria, Bacteroidetes, and Firmicutes were found to be predominant at phylum level treating aniline wastewater. Blastocatella, Ferruginibacter and Clostridium were predominant strains involved in aniline degradation and Pseudomonas was enriched in the presence of aniline. Aeromonas, Acinetobacter, and Comamonas may play key roles in nitrogen removal and phosphorus accumulation with tolerance of aniline.

As quadrotor unmanned aerial vehicles (UAVs) being developed rapidly, many advance control methods have been proposed to meet higher requirement of tracking performance. However, the disturbance rejection in guidance and control is still an open issue. As an effective disturbance rejection method, composite hierarchical anti-disturbance control (CHADC) can compensate and attenuate disturbances simultaneously, which can handle complicated cases. To enhance the capability of autonomous anti-disturbance, this paper proposes a novel composite hierarchical anti-disturbance (CHAD) predictor-corrector (PC) scheme for quadrotor UAVs. The disturbances and uncertainties are partially estimated and compensated by disturbance observer, while the rest of them are regulated dynamically via PC. Finally, simulation and experiment results demonstrate the effectiveness of proposed method.

Probiotic bacteria has been found to exert anti-tumour effects against colon cancer. The possible mechanisms of probiotics in prevention and treatment of colon cancer include adjusting intestinal flora, regulating microflora metabolites, maintaining intestinal homeostasis, inducing immune regulation, antioxidant activity, inducing apoptosis and anti-inflammation.

To discuss through retrospective study associated factors influencing orthodontists to develop orthodontic treatment plans and to calculate constituent ratio of a typical extraction in orthodontic treatment.Systematic sampling was performed among 7 344 orthodontic patients, who received orthodontic treatment from April 2012 to March 2014 in the Department of Orthodontics, West China Hospital of Stomatology, Sichuan University. The study included statistical data on factors that may influence development of treatment plans. Samples were used to calculate extraction-ratio and atypical-extraction-ratio. Research focused on associated factors influencing development of treatment plans while evaluating correlation significances of each factor. Finally, treatment outcomes of atypical-extraction were compared with those of typical-extraction.Among studied patients, 55.31% (406/734) received orthodontic extraction treatment. In orthodontic-extraction-treated patients, typical-extraction accounted for 59.11% (240/406), orthodontists-selected atypical-extraction accounted for 23.15% (94/406), and passive atypical-extraction accounted for 17.73% (72/406). With statistical analysis, we inferred associated factors influencing development of treatment plans as follows: sex and age of patients, sex of orthodontists, accurate condition of specific teeth, Angle's classification, and degree of midline deviation. Tooth loss before treatment also directly influences passive atypical-extraction. Statistically significant factors were not obtained. Significant difference of treatment outcome was not observed between atypical-extraction and typical-extraction-orthodontic treatment (P0.05).Above mentioned factors may influence orthodontists to develop treatment plans. However, orthodontists should also consider expected results of treatment strategies to prepare individual treatment plans on the basis of comprehensive analysis. .目的 通过回顾性研究，对非常规拔牙在固定正畸治疗中的构成比以及影响拔牙方案选择的相关因素进行探讨。方法 对四川大学华西口腔医院正畸科2012年4月—2014年3月两年间有病历资料记录的7 344例固定正畸患者进行系统抽样，对抽取的734例样本的矫治方案及多项可能对矫治方案有影响的因素进行统计，计算拔牙矫治率、非常规性拔牙矫治率，重点研究影响非常规拔牙的相关因素，并对所有因素进行统计学分析，以评价其对非常规拔牙矫治方案制定的影响程度；对其中部分病例进行非常规拔牙和常规拔牙的疗效对比评价。结果 约55.31%（406/734）的患者采用拔牙矫治，其中常规拔牙矫治占59.11%（240/406），主动性非常规拔牙占23.15%（94/406），被动性非常规拔牙占17.73%（72/406）。经统计分析，对主动性非常规拔牙方案制定有影响的因素有患者性别、年龄、医生性别、个别牙情况、Angle分类、中线偏斜程度等6项因素；对于被动性非常规拔牙，就诊前相应牙的缺失或被拔除是其直接影响因素。非常规拔牙和常规拔牙的矫治效果无统计学差异（P0.05）。结论 患者性别、年龄、医生性别、个别牙情况、Angle分类、中线偏斜程度、就诊前是否有牙缺失等因素对患者矫治方案的制定有一定影响；此外，还应同时考虑到矫治方案的预期效果，综合分析以制定个体化矫治方案。.

The industrial microorganisms used for fructooligosaccharides (FOS) synthesis are generally fermented with sucrose as carbon source to induce the production of β-fructofuranosidase (FFase) having transfructosylation activity. Consequently, isolation of novel FFase producers from a sucrose-enriched biotope would help improve FOS productivity and reduce the process cost. Here, three fungi isolated from a unique sugarcane molasses habitat were found to possess FFase activity and one of them, XG21, exhibited a high capacity to synthesize FOS. Analysis of its morphological properties and ribosomal internal transcribed spacer (ITS) sequence allowed the taxonomic position to be assigned and it was thus identified as Aspergillus tubingensis XG21. It could utilize various potential carbon sources for vigorous growth, but only produced high-level FFase activity on sucrose. Furthermore, the transfructosylation ability and FOS synthesis were analyzed by TLC and HPLC. During the transfructosylation reaction, an increase in sucrose concentration led to the remarkable enhancement in FOS formation with the maximum content of up to 56.9% within 8 h. Finally, the sugarcane molasses was used to cultivate A. tubingensis XG21 and the optimal FFase activity reached up to 558.3 U/g, which was 88.9% higher than that with sucrose as carbon source. These results indicate that A. tubingensis XG21 can be considered as a new genetic resource adapted to cheaply available carbon sources for FOS production.

Aspergillus niger ATCC20611 is one of the most potent filamentous fungi used commercially for production of fructooligosaccharides (FOS), which are prospective components of functional food by stimulating probiotic bacteria in the human gut. However, current strategies for improving FOS yield still rely on production process development. The genetic engineering approach hasn't been applied in industrial strains to increase FOS production level. Here, an optimized polyethylene glycol (PEG)-mediated protoplast transformation system was established in A. niger ATCC 20611 and used for further strain improvement. The pyrithiamine resistance gene (ptrA) was selected as a dominant marker and protoplasts were prepared with high concentration (up to 108g-1 wet weight mycelium) by using mixed cell wall-lysing enzymes. The transformation frequency with ptrA can reach 30-50 transformants per μg of DNA. In addition, the efficiency of co-transformation with the EGFP reporter gene (egfp) was high (approx. 82%). Furthermore, an activity-improved variant of β-fructofuranosidase, FopA(A178P), was successfully overexpressed in A. niger ATCC 20611 by using the transformation system. The transformant, CM6, exhibited a 58% increase in specific β-fructofuranosidase activity (up to 507U/g), compared to the parental strain (320U/g), and effectively reduced the time needed for completion of FOS synthesis. These results illustrate the feasibility of strain improvement through genetic engineering for further enhancement of FOS production level.

OBJECTIVE: To assess the quality of reporting by randomized controlled trial (RCT) related to dental implants in China during 2000 to 2012 by using the revised Jadad scale and consolidated standards of reporting trials (CONSORT) (2010) statement. METHODS: The following electronic databases were searched: Chinese Biomedical Literature Database, Database for Chinese Technical Periodicals, China National Knowledge Infrastructure, PubMed, and EMBASE. A total of 19 journals of stomatology in China were also searched manually. The qualities of RCT with dental implant published between 2000 and 2012 were assessed using CONSORT (2010) statement and revised Jadad scale. RESULTS: Twenty-eight RCTs related to dental implants were identified. The quality of reporting in 28 articles was low. The mean revised Jadad score was 1.29±0.71 and the CONSORT (2010) score was 9.75±3.60. CONCLUSION: The methodological qualities of the included studies on dental implants are generally low, and reporting quality remain unsatisfactory.