This application requests funds for a PerkinElmer/Caliper Quantum FX Micro-CT Scanner to support research being carried out at Tufts University, Tufts Medical Center (TMC) and the Tufts Jean Mayer USDA Human Nutrition Research Center in Boston. A group of 9 well-funded NIH investigators will be the major users of the instrument and along with 6 additional users will account for approximately 75% of its use. Cutting edge projects in the areas of cancer, cardiac and metabolic diseases and tissue engineering are described. Need for the instrument at this time is critical as there is currently n Micro-CT instrument available at either Tufts University or Tufts Medical Center for the projects that are described. The system will be housed in the Tufts/TMC Small Animal Imaging Preclinical Testing Facility where it will complement existing optical and ultrasound imaging equipment. Choice of the system was based on its demonstrated suitability for the proposed projects, its ability to produce high quality images at significantly lower radiation dose, evidenc of reliability from users at other institutions, and its relative ease of use and integration with other facility imaging equipment. Addition of the instrument to the Facility is strongly supported by the President of Tufts University, Deans of the Medical and Dental School, Directors of Jean Mayer Human Nutrition Center and the Cancer Center at Tufts Medical Center and the Chairman of the Department of Molecular Physiology and Pharmacology where the Facility is physically located. The Dean of the Medical School has pledged renovated space for the instrument;exceptional institutional support for instrument in the form of service contract support for 3 years will be provided by the institutions involved. The Facility is directed by the I and the instrument will be managed and operated on a day-to-day basis by the Associate Director and Technician/Manager of the Facility, who will also train new users. The PI and several major users have expertise in micro-CT and the Associate Director of the Facility will be trained at the NIH Mouse Imaging Facility in micro-CT fundamentals and instrument use. Two diagnostic imaging radiologists with CT expertise will serve as consultants to support the instrument and its users. An advisory committee consisting of the PI, representatives from Tufts University, Tufts Medical Cancer, the USDA Human Nutrition Research Center, the Department of Molecular Physiology and Pharmacology and the Division of Laboratory Animal Medicine will oversee use of the Quantum FX Micro-CT Scanner and develop policies for use and equitable sharing of the instrument. The availability of the Caliper Quantum FX Micro-CT Scanner will greatly enhance the quality NIH-funded research being carried out Tufts University and Tufts Medical Center and will stimulate translation research and collaboration among the various components of the Tufts research community.