The objectives of this proposal can be summarised as follows:Scientific aim:The proposed project is focused on the onset of nuclear activity in the absence of interactions. The dense and warm molecular gas plays a key role in this process, and its morphology, kinematics and physical properties will be traced by means of (sub)millimeter data using the first interferometer working at submillimeter wavelengths, the Submillimeter Array (SMA).This study will allow selecting the best candidates to be followed up with the high angular resolution provided by ALMA. This research will be performed in the framework of the AMIGA international collaboration (http://www.iaa.es/AMIGA.html) whose aim is to study the interplay between interstellar medium, star formation and nuclear activity in a well-defined sample of the most isolated galaxies.Technical aim:- Participation in the development of a submillimeter calibration scheme for SMA. This is especially relevant and directly applicable to the development an d commissioning of the Atacama Large Millimeter Array (ALMA), instrument that is being built by an international consortium -Europe, USA and Japan- and is one of the most important investments of the European ground-based astronomy.- Development of data mining tools for (sub)millimeter interferometry, focusing in a pre-reduction pipeline. These tools are particularly necessary in view of the large amount of data that SMA and ALMA will generate. The scientific and technical progress in submillimeter astronomy will culminate with ALMA due to its unprecedent resolution and sensitivity.The commisioning phase will begin soon (2007) and is expected to be completely finished by 2012. With the here proposed project the applicant intends to be prepared before the ALMA commissioning phase starts, in order to participate in an efficient recovery of the European investment in the ALMA project, both scientific and technically.