Abstract: A ticket issuer server for receiving purchase requests for contents transmits a ticket, storing a charges receiving entity identifier as contents charges information and data of distribution charges with regard to the charges receiving entity, to a user device, under the condition that billing processing for the contents purchase request of the user device has ended, and executes cashing processing based on receipt of the ticket from the user device. Also, contents purchase log data is collected according to updating processing of a public key certificate of the user device which purchases contents, and further, between entities executing data communication, attributes information is obtained from a public key certificate or attributes certificate of the entity which is the other party of communication, and attributes confirmation based on the obtained attributes information is performed, so processing in guise of another entity can be prevented.

Abstract: Novel foam proteins, monoclonal antibodies specifically recognizing said proteins, a method for determining foam protein contents in beer samples by an immunoassay using said monoclonal antibodies, a method for determining head retention and head retention stability of beer, as well as a method for evaluating raw materials of beer and stabilizers for beer are disclosed. The novel foam proteins crucial for head retention of beer have molecular weights of about 40000 to about 48000 as determined by Western blot analysis.