PARAMETRIC MATCHING SELECTION OF MULTI-MEDIUM COUPLING SHOCK ABSORBER

To achieve the dual demand of resisting violent impact and attenuating vibration in vibration-impact-safety of protection for precision equipment such as MEMS packaging system, a theo- retical mathematical model of multi-medium coupling shock absorber is presented. The coupling of quadratic damping, linear damping, Coulomb damping and nonlinear spring are considered in the model. The approximate theoretical calculating formulae are deduced by introducing transformation-tactics. The contrasts between the analytical results and numerical integration results are developed. The resisting impact characteristics of the model are also analyzed in progress. In the meantime, the optimum model of the parameters matching selection for design of the shock absorber is built. The example design is illustrated to confirm the validity of the modeling method and the theoretical solution.

Isolation and Identification Methods for Oral Klebsiella pneumoniae Involved in Onset of Inflammatory Bowel Disease

Purpose: Recently, it was reported that Klebsiella pneumoniae is related to the onset of inflammatory bowel disease including the Crohn disease. It was frequently reported that K. pneumoniae was detected in human oral cavities. Regrettably, it currently remains unclear whether K. pneumoniae is part of the normal oral flora. The aim of this study was to establish the isolation and identification methods for K. pneumoniae from human oral cavities, and investigate its transmission pattern. Methods: A selective medium, OKPSM, for the isolation of K. pneumoniae from oral cavities was developed in this study. Also, PCR primer for the identification and detection at subspecies level of K. pneumoniae was designed. Results: OKPSM and PCR method using the primers designed in this study were useful for the isolation and identification of K. pneumoniae from human oral cavities. K. pneumoniae subsp. pneumoniae was detected at 10.0% in 30 saliva samples. On the other hand, K. pneumoniae subsp. ozaenae and K. pneumoniae subsp. rhinoscleromatis were detected from no sample. Moreover, K. pneumoniae subsp. pneumoniae isolates from same subject at 0 month and after 3 months showed same genotypes on AP-PCR using OPA-07 primer. Conclusion: These results indicated that human oral cavities were not suitable for the habitat of K. pneumoniae.

Novel Isolation and Identification Methods for Veillonella Species Involved in Halitosis

Purpose: The purpose of the present study was to develop a novel selective medium (OVSM) and useful identification method for oral Veillonella species, to assess the prevalence of this species using the selective medium, and to investigate whether the monitoring of oral Veillonella species levels is useful as a clinical indicator for the diagnosis of halitosis. Methods: To examine bacterial populations in the oral cavity, a novel selective medium (OVSM) and multiplex PCR method were developed for isolating and identifying oral Veillonella species. OVSM consists of tryptic soy agar, sheep blood, sodium lactate, vancomycin, and oxacillin. Results: Oral Veillonella species grew well on OVSM. Oral Veillonella species accounted for 5.4% and 27.2%, respectively, of all bacteria in the tongue biofilm samples of healthy and halitosis subjects. Oral Veillonella species produced larger amounts of volatile sulfur compounds than other representative oral bacteria. Conclusion: These results indicate that monitoring the levels of these organisms is useful as a clinical indicator for the diagnosis of halitosis.

Isolation and Identification Methods for Actinomyces israelii Involved in Actinomycosis

Purpose: Actinomyces israelii is known as the key species to cause classical actinomycosis. Although A. israelii is frequently isolated from human oral cavities, the distribution of this microorganism has been little reported. The purpose of the present study was to develop selective media (AISM) for the isolation of A. israelii and to assess the prevalence of this organism in the oral cavity. Methods: To examine the bacterial population in the oral cavity, a novel selective medium (AISM) was developed for isolating A. israelii. AISM consists of BHI, yeast extract, agar, ofloxacin, fosfomycin, colistin, and sodium fluoride. Results: A. israelii strains grew well on AISM. A. israelii was detected in all dental plaque samples collected from 20 subjects and the mean number of this organism in the samples was 7.9 × 104 CFU/ml. Conclusion: These results indicated that the selective medium was useful for the isolation of A. israelii and this organism was a part of the normal flora in the human oral cavity.