Dale Schoeller

Credentials: Professor Emeritus

Position title: Core Director

Phone:(608) 262.1082

425 Henry Mall
Biotechnology Center, 2nd Floor, Room #2210
Madison WI 53706

Dr. Schoeller obtained his Ph.D. in chemistry and geochemistry from Indiana University, where he received training in isotope ratio mass spectrometry for applications in geochemistry and biology. He possesses extensive expertise in light isotope biogeochemistry, vacuum technology, mass spectrometry, and computer interfacing and programming. Following his doctoral studies, he spent two years as a Post-doctoral Fellow at the Argonne National Laboratory, focusing on developing stable isotope tracer methods to investigate human metabolism.

Later, Dr. Schoeller joined the Department of Medicine at the University of Chicago, where he served as the director of the Stable Isotope Core within the Clinical Nutrition Unit. In 1997, he assumed the role of Professor of Nutritional Sciences at the University of Wisconsin-Madison, specializing in research related to human obesity. In 2013, he transitioned to the position of Professor Emeritus and became part of the Biotechnology Center.

Dr. Schoeller holds the distinction of being the first to utilize the doubly labeled water method for measuring Total Energy Expenditure (TEE) in humans. His groundbreaking work, conducted in collaboration with van Santen in 1984, involved optimizing protocols for human use, devising the calculations still employed today, and pioneering the method’s initial applications in human health research. Presently, he directs the laboratory responsible for performing doubly labeled water analyses and offers guidance to researchers seeking collaboration with the Isotope Ratio Laboratory.

Michele N. Ravelli

Credentials: Ph.D. in Food and Nutrition Science

Position title: Scientist II

Phone:(608) 263.5477

425 Henry Mall
Biotechnology Center, 2nd Floor, Office #2104
Madison WI 53706

Dr. Ravelli is an accomplished investigator in the field of Nutrition and Obesity Science. She completed her MS and Ph.D. training at the Sao Paulo State University (Unesp), focusing on the accuracy of self-reported dietary intake of obese individuals and conducting stable isotope studies. At the Stable Isotope Center in Brazil, she optimized the doubly labeled water method for measuring energy expenditure and explored the effects of obesity and bariatric surgery on energy balance.

Throughout her career, Dr. Ravelli has actively engaged in interdisciplinary collaboration. Working closely with experts in bariatric surgery, endocrinology, nutrition, and kinesiology, she has gained valuable insights into the health implications of obesity and energy balance. Her expertise includes the application of stable isotope methods to investigate human health and disease, particularly in understanding changes in energy balance components and weight outcomes.

Dr. Ravelli’s career pathway demonstrates her commitment to advancing knowledge in the field. Her research achievements, alongside extensive involvement in nutrition research and clinical assistance, have contributed to a deeper understanding of energy balance, weight management, and the utilization of stable isotope techniques. With a strong foundation in Nutrition and Obesity Science, Dr. Ravelli continues to make noteworthy contributions through interdisciplinary collaborations and her expertise in measuring energy balance and factors related to obesity.

Timothy Shriver

Credentials: Master’s Degree in Exercise Physiology

Position title: Senior Research Specialist


425 Henry Mall
Biotechnology Center, 2nd Floor, Lab Room # 2210
Madison WI 53706

Tim Shriver holds a master’s degree in Exercise Physiology and has been a Senior Research Specialist at the Stable Isotope Ratio Laboratory since 1997. He plays a crucial role in the laboratory’s daily operations, overseeing the isotope ratio mass spectrometer and ensuring its smooth functioning. This includes conducting annual preventive maintenance and performing repairs when necessary. With his extensive experience, Tim has developed a deep understanding of the Thermo Fisher software operating system, quality control procedures for isotope ratio data, isotope calculations, and maintenance of the vacuum system.

In addition, Tim is responsible for liaising with Thermo Fisher mass spectrometer personnel to troubleshoot and replace any faulty electronic modules, instrument computer systems, autoinjectors, or inlet systems that may occasionally require attention.

Tim’s expertise extends to the field of isotope hydrology, where he specializes in analyzing natural abundance isotope data to investigate food webs. He is well-versed in handling various sample types, including water, blood products, and bulk tissues from both animals and humans. His knowledge and skills contribute significantly to the successful execution of research projects within the laboratory.