? Research Development Core The SD-NSC Research Development Core (ResDev Core) will provide support for career development of junior researchers entering the field of basic aging biology, as well as established investigators who wish to join the field of aging research. Specifically, the ResDev Core will support the scientific goals of SD-NSC to enhance the understanding of the role of cell heterogeneity in the aging process by promoting career development of aging researchers in three different ways: 1) by providing seed funding for projects interested in taking advantage of the unique scientific services offered by the SD-NSC Research Resource Cores (Human Cell Models of Aging Core, Heterogeneity of Aging Core, and Integrative Models of Aging Core), 2) by providing conceptual and practical training in the scientific services covered by the three Research Resource Cores, and 3) by establishing a personalized mentoring program between junior and senior members of the NSC network and beyond. The ResDev Core will be led by Dr. Malene Hansen, Sanford Burnham Prebys Medical Discovery Institute (SBP), who brings local, national, and international aging research knowledge, and extensive expertise and high motivation in mentoring junior scientists. The approach will capitalize on a highly integrative and innovative approach by providing conceptual and practical training in the scientific Cores along with formalized mentoring in grant writing and career development. First, a two-track pilot grant program will be launched in which applicants apply for funding for Core usage and mentoring, either directly from submitted applications or via a grant-writing support program. Second, a one-day workshop to provide training in the scientific Cores will take place the day after the yearly La Jolla Aging Meeting, a free one-day aging symposium at the Salk Institute for Biological Studies (Salk) in San Diego organized by researchers at Salk and SBP. This workshop will feature modules on the techniques and analyses provided by the three scientific cores, along with information about potential career tracks in scientific Core services. In addition, a module on grant writing will be offered. Third and finally, a two-track personalized mentoring program will be established in which junior researchers will be mentored by established investigators, either as part of the pilot grant program or via pairing of mentee-mentor relationships formed at national NSC meetings, and beyond.