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The aim of this study was to identify genes conferring resistance to fluoroquinolones and extended-spectrum β-lactams in non-typhoidal Salmonella (NTS) from food-producing animals in China. In total, 31 non-duplicate NTS were obtained from food-producing animals that were sick. Isolates were identified and serotyped and the genetic relatedness of the isolates was determined by pulsed-field gel electrophoresis of XbaI-digested chromosomal DNA. Antimicrobial susceptibility was determined using Clinical and Laboratory Standards Institute methodology. The presence of extended-spectrum β-lactamase (ESBL) and fluoroquinolone resistance genes was established by PCR and sequencing. Genes encoded on transmissible elements were identified by conjugation and transformation. Plasmids were typed by PCR-based replicon typing. The occurrence and diversity of numerous different transmissible genes conferring fluoroquinolone resistance [qnrA, qnrD, oqxA and aac(6')-Ib-cr] and ESBLs (CTX-M-27 and CTX-M-14), and which co-resided in different isolates and serovars of Salmonella, were much higher than in European countries. Furthermore, different plasmids encoded fluoroquinolone resistance (ca. 6 kb) and β-lactam resistance (ca. 63 kb) and these co-resided in isolates with mutations in topoisomerase genes (gyrA and parC) giving very resistant Salmonella. The presence of multidrug-resistant bacteria in food-producing animals in countries that export foodstuffs suggests that global transfer of antibiotic resistances from country to country on food is possible.

The study object is wheat. Through the observation and analysis on the morphological structure of wheat plant, the concepts of microstate, substrate and microstate are put forward, the wheat growth mechanism model is established, and thus the description and control of wheat morphogenesis process could be realized. Based on the branch structure characteristics of plant, the wheat morphological data model based on axis structure is proposed to realize the structural storage of plant topological structure and organ morphological feature data. On this basis, based on the thought of "growth model - morphological feature model - geometric modeling - display model", the technical framework of wheat form visualization is established and on the VC++ platform, the virtual wheat growth system is built with OpenGL. The running result of the system shows that wheat morphological feature can be well simulated with the system to realize the virtual display of the growth process in the individual growth period of wheat.

In order to speed up the vehicles through the expressway toll station and reduce traffic congestion, we analysed of the No-waiting ETC(Electronic Toll Collection System) of expressway unifying the ETC theory and the RFID(Radio Frequency Identification Devices) technology. Firstly, we analysed system's hierarchy architecture, then detailed analysed the basic component of system, and designed the workflow and composing of functional modules, finally, established the model of ETC system of expressway based on RFID, it provides more practical guidance scheme for expressway ETC system.

In order to achieve the digital management of null-pollution agricultural products certification and by adopting techniques such as Web Service, distributed database and workflow, this essay has completed the design and development of the system based on the J2EE platform. It includes certification data service subsystem, declare subsystem and certification workflow management subsystem. This system can highly automize and standardize the key link of origin and product certification such as the review of filing materials, site inspection and environment detection. It can automatically generate filing materials, inspection report and evaluation report. It has the function of sending documents among certification management departments at various levels and storing them respectively. This system has speed up the agricultural products origin and product certification integration process and realized standardized and digitalized management of certification work.