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Background: The increasing occurrence of livestock-associated (LA) methicillin-resistant Staphylococcus aureus (MRSA) associated with the clonal complex (CC) 398 within the past years shows the importance of standardized and comparable typing methods for the purposes of molecular surveillance and outbreak detection. Multiple-locus variable number of tandem repeats analysis (MLVA) has recently been described as an alternative and highly discriminative tool for S. aureus. However, until now the applicability of MLVA for the typing of LA-MRSA isolates from different geographic origin has not been investigated in detail. We therefore compared MLVA and S. aureus protein A (spa) typing for characterizing porcine MRSA from distinct Dutch and German farms. Methodology/Principal Findings: Overall, 134 MRSA isolates originating from 21 different pig-farms in the Netherlands and 36 farms in Germany comprising 21 different spa types were subjected to MLVA-typing. Amplification and subsequent automated fragment sizing of the tandem repeat loci on a capillary sequencer differentiated these 134 isolates into 20 distinct MLVA types. Whereas overall MLVA and spa typing showed the same discriminatory power to type LA-MRSA (p = 0.102), MLVA was more discriminatory than spa typing for isolates associated with the prevalent spa types t011 and t034 (Simpson's Index of Diversity 0.564 vs. 0.429, respectively; p<0.001). Conclusion: Although the applied MLVA scheme was not more discriminatory than spa typing in general, it added valuable information to spa typing results for specific spa types (t011, t034) which are highly prevalent in the study area, i.e. Dutch-German border area. Thus, both methods may complement each other to increase the discriminatory power to resolute highly conserved clones such as CC398 (spa types t011, t034) for the detection of outbreaks and molecular surveillance of zoonotic MRSA. [ABSTRACT FROM AUTHOR]

Since 1998, large investment banks have become active as issuers of options, generally referred to as call warrants or bank-issued options. This has led to an interesting situation in the Netherlands, where simultaneously call warrants are traded on the stock exchange, and long-term call options are traded on the options exchange. Both entitle their holders to buy shares of common stock. We start with a direct comparison between call warrants and call options, written on the same stock and with the same exercise price, but where the call option has a longer time to maturity. In 13 out of 16 cases we find that the call warrants are priced higher, which is a clear violation of basic option pricing rules. In the second part of the analysis we use option pricing models to compare the pricing of call warrants and call options. If implied standard deviations from options are used to price the call warrants, we find that the call warrants are strongly overpriced during the first five trading days. The average overpricing is between 25 and 30%. Only a small part of the overpricing can be explained by rational arguments such as transaction costs. We suggest that the overvaluation can be explained by a combination of an active financial marketing by the banks and the framing effect. [ABSTRACT FROM AUTHOR]