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A list of the eleven tested antimicrobials, their classes, their concentrations, and their breakpoints used for susceptibility testing of E. coli. (DOC 58 kb)

The scattering effect of laser-transparent part has significant influence on the intensity profile of heat source during laser transmission welding (LTW). The purpose of the present study is to propose a method for modeling the laser heat source considering light scattering. The knife-edge experiment is served to obtain the normalized power flux distribution (NPFD) without considering light scattering, and the non-contact line scanning experiment is used to describe the NPFD considering light scattering. Subsequently, the energy transformation algorithm is presented to transform the normalized line energy intensity into the normalized point energy intensity. Then the heat source considering light scattering can be modeled based on the distribution of point energy intensity. Compared with the heat source without considering light scattering, the intensity profile of heat source considering light scattering shows a wider width and a lower peak height. Especially when the laser-transparent part contains reinforcements, the difference of intensity profile is more evident than the unreinforced laser-transparent part. This indicates that light scattering has a significant influence on the laser intensity at the weld interface. The proposed method for modeling the heat source, considering light scattering, can optimize the laser source in the numerical simulation of LTW.

A list of the eleven tested antimicrobials, their classes, their concentrations, and their breakpoints used for susceptibility testing of E. coli. (DOC 58Â kb)

To satisfy the need of polymer connection in lightweight automobiles, a study on laser transmission spot welding using polymethyl methacrylate (PMMA) is conducted by using an Nd:YAG pulse laser. The influence of three variables, namely peak voltages, defocusing distances and the welding type (type I (pulse frequency and the duration is 25 Hz, 0.6 s) and type II (pulse frequency and the duration is 5 Hz, 3 s)) to the welding quality was investigated. The result showed that, in the case of the same peak voltages and defocusing distances, the number of bubbles for type I was obviously more than type II. The failure mode of type I was the base plate fracture along the solder joint, and the connection strength of type I was greater than type II. The weld pool diameter:depth ratio for type I was significantly greater than type II. It could be seen that there was a certain relationship between the weld pool diameter:depth ratio and the welding strength. By the finite element simulation, the weld pool for type I was more slender than type II, which was approximately the same as the experimental results.

To determine effect of sulbactam and EDTA on antibacterial activity of antimicrobial drugs in vitro,MIC of 10 antimicrobial agents alone and their respective combinations with sulbactam,EDTA and sulbactam+ EDTA against ESBLs-producing E.coli,were determined by using broth microdilution method.The results showed that sulbactam and EDTA can enhance antibacterial activity of parts of antimicrobial agents,the resistant rate of ESBIs-producing isolates to third generation cephalosporin ceftiofur,cefotaxime was higher than 80% and the resistant rates to fluoroquinolones,doxycycline,florfenicol,amikacin and fosfomycin were up to 100%.All the ESBIs-producing isolates were sensitive to cefepime.The resistant rate to third generation cephalosporin cefotaxime,florfenicol,amikacin and fosfomycin combinations with sulbactam,were lower than that to antibacterial drugs alone,is 0,88.9%,88.9%,0 respectively.The resistant rate to gatifloxacin,doxycycline,florfenicol,amikacin and fosfomycin combinations with EDTA,were lower than that to antibacterial drugs alone,is 30%,11.1%,22.2%,11.1%,0 respectively.The resistant rates of most strains to sulbactom+EDTA amikacin,fosfomycin,florfenicol and ceftiofur combinations were much lower than those combinations either only sulbactam or EDTA and were all 0.