MOTIVATION: A vast amount of information about human, animal and plant pathogens has been acquired, stored and displayed in varied formats through different resources, both electronically and otherwise. However, there is no community standard format for organizing this information or agreement on machine-readable format(s) for data exchange, thereby hampering interoperation efforts across information systems harboring such infectious disease data. RESULTS: The Pathogen Information Markup Language (PIML) is a free, open, XML-based format for representing pathogen information. XSLT-based visual presentations of valid PIML documents were developed and can be accessed through the PathInfo website or as part of the interoperable web services federation known as ToolBus/PathPort. Currently, detailed PIML documents are available for 21 pathogens deemed of high priority with regard to public health and national biological defense. A dynamic query system allows simple queries as well as comparisons among these pathogens. Continuing efforts are being taken to include other groups' supporting PIML and to develop more PIML documents. AVAILABILITY: All the PIML-related information is accessible from http://www.vbi.vt.edu/pathport/pathinfo/

There are two basic approachs to the problem of storage reclamation, process- and processor-based, named for the view point used to recognize when a particular piece of storage can be reclaimed. Examples of the processor approach include mark/sweep and copying algorithms and their variants, while reference counting schemes use a process view of the collection. It is argued that the process approach is better suited for distributed computation where links between dynamically allocated objects may cross processor boundaries. In addition, the process approach allows the heap to be more conveniently shared with other processes in those cases when different processes might not have their own virtual address spaces. A new algorithm using the process approach is given. Its space requirement per object is better than that for reference counting. In addition, a restricted form of pointer replacement is supported which allows circular structures so constructed to be properly collected.