Dynamics of change in research work: Constructing a new research area in aresearch group

The authors study how an aerosol technology research group constructed a re search agenda for itself and how its activity was changed in the process. T he group's research agenda was heterogeneous, comprising several research a reas in which the knowledge of aerosols was applied in different industrial contexts. The authors analyze the development of one of these areas, the r esearch on the production of ultrafine particles from 1992 to 1997, employi ng the concept of mediated activity that has been developed in the cultural -historical theory of activity. In the analysis, the activity is seen as th e coevolution of the subject, the means, and the research object and the ne tworks of collaboration with other activities. The applications developed i n the collaborative networks significantly influence the identity and learn ing of the researchers, the construction of tools and instruments, and the selection of the phenomena to be studied.