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The aerodynamic performance of high-speed trains is closely related to their head shape. As each train set has its own modelling system, the aerodynamic shape design of head type of a high-speed train must follow a pedigree modelling approach. The train pedigree characteristics directly reflect its aerodynamic performance. The focus of this study is the extraction and application of the Shinkansen train pedigree features. First, largescale differences in train head shapes are eliminated by dimensionless elimination. Second, the Shinkansen model pedigree features are extracted using similarity calculations. Finally, based on the constraint range of pedigree features on the new model shape, the concept head shape is designed with reference to the shape and surface parameters of high-speed trains, and its aerodynamic performance is verified. The results of the aerodynamic verification indicate that the concept design reduces the drag by more than 10% compared to the E2 Series base model. Additionally, the results demonstrate that the extraction and design application of train pedigree features can help a new train to develop its aerodynamic shape within its own pedigree modelling system, thus enabling the synergistic design of train shape and aerodynamic performance. [ABSTRACT FROM AUTHOR]

Author(s): B. Q. Lv [1, 2]; Z.-L. Feng [1, 2]; Q.-N. Xu [1, 2]; X. Gao [1, 2]; J.-Z. Ma [1, 2]; L.-Y. Kong [1, 2]; P. Richard [1, 2, [...]

Purpose: To establish a new genotyping method for Vibrio cholerae and compare it with other methods., Materials and Methods: In the current study, a modified inter simple sequence repeat-polymerase chain reaction (MISSR-PCR) system was developed via several rounds of optimisation. Comparison study was then conducted between MISSR-PCR and three other methods, including enterobacterial repetitive intergenic consensus sequences-based PCR (ERIC-PCR), randomly amplified polymorphic DNA (RAPD) and 16S rRNA evolutionary clock, for the detection and genetic tracing of Vibrio cholerae isolated from seafood in China., Result: The results indicated that the MISSR-PCR system could generate the highest polymorphic fingerprinting map in a single round PCR and showed the best discriminatory ability for Vibrio cholerae genotyping by clearly separating toxigenic/nontoxigenic strains, local/foreign strains, and O1/O139/non-O1/non-O139 serogroup strains, comparing to ERIC-PCR, RAPD and 16S rRNA evolutionary clock. Moreover, the MISSR-PCR is superior to previously described traditional simple sequence repeat based PCR method on genotyping by more clearly separating different clusters., Conclusion: To the best of our knowledge, this is the first head-to-head comparison of four detection and genotyping methods for Vibrio cholerae The MISSR-PCR system established here could serve as a simple, quick, reliable and cost-effective tool for the genotyping and epidemiological study.

Riboflavin status was surveyed in adults aged 35-64 y in 65 counties (two communes per county) in the People's Republic of China by erythrocyte glutathione reductase activity coefficients (EGRACs), by urinary excretion of riboflavin 4 h after the oral administration of 5 mg riboflavin (one commune per county), and by direct measurement of food intake over a 3-d period (one commune per county). EGRAC data were highly correlated between sexes (p less than 0.001) and between neighboring communes within the same county (p less than 0.001) and with riboflavin intake (p less than 0.001). The urinary-riboflavin-load test data were not correlated either with EGRAC or with riboflavin intake. Approximately 90% of the survey subjects were found to be deficient by Western and Chinese reference standards and allowances. Upon reconsideration of the Western experimental data originally used to establish these recommendations, it is suggested that riboflavin allowances are set too high both in China and in Western countries.