A computer-implemented service recommends merchants affiliated to one or several financial transaction networks based on transaction information and other available information. Correspondingly, the present disclosure also provides a client terminal, server and data synchronization system. Conventional glycol-based coolants typically used for internal combustion engines are generally unsuitable for use in the associated fuel cell cooling subsystems due to the presence of additives andor inhibitors which are normally included to deal with problems relating to decomposition of the glycol. A contact layer of the second conductivity type is formed on the second layer.