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OCS Biographies


Dionne Toombs, Director for the Office of the Chief Scientist

Dr. Dionne Toombs is the Director for the Office of the Chief Scientist (OCS). In this role, she provides leadership on a wide range of issues affecting science programs and science policy in agricultural research, education, and economics. She comes to OCS from the National Institute of Food and Agriculture (NIFA) where she was Director of the Division of Nutrition, leading a collaboration of nutrition science leaders across the Department. ?Under her leadership, the Division provided direction in science policy and program development to ensure the safety of America’s food supply and the availability of healthy food to its citizens.

She served as National Program Leader for NIFA’s Agriculture Food and Research Initiative (AFRI), leading large competitive grant programs to fund research into nutrition, food science and technology, and food safety.

Dr. Toombs received her Ph.D. in Nutritional Sciences from Howard University. She earned her Master of Science degree from Alabama A & M University and her Bachelor of Science degree in Biology from Bethune-Cookman University.

Richard Derksen, Deputy Director of the Office of the Chief Scientist

Richard (Rich) Derksen is the Deputy Director of the Office of the Chief Scientist (OCS). In this role, he provides direction and leadership on a wide range of issues affecting programs in agricultural research, education, and economics. Derksen manages review and product activity, tracks metrics, output, and impacts, and represents OCS on various Federal working groups and committees.

Derksen has over 25 years of direct research experience. He is an internationally recognized expert in crop production and protection engineering. At Cornell University, he held a joint research and extension appointment related to crop protection. In 1996, Derksen joined the Agricultural Research Service as a research scientist with a focus on providing engineering solutions to crop production and protection issues. He has authored over 200 publications, including 78 peer-reviewed journal manuscripts and given numerous invited presentations at national and international scientific meetings. Derksen received his Master of Science and Ph.D. degrees in Agricultural Engineering from the University of Illinois.

Advisors and Staff

Jaime Adams, Senior Advisor for International Affairs

Jaime Adams joined the Office of the Chief Scientist in 2011 as the Senior Advisor for International Affairs. In this capacity, Ms. Adams engages in cross-functional international agricultural science and technology collaboration with all levels of staff and leadership from government and non-governmental organizations. Ms. Adams' portfolio includes management of a multi-million dollar project and management and negotiation of numerous international bilateral and multilateral agricultural science and technology relationships. Ms. Adams manages the U.S. Government (USG) participation in the Global Open Data for Agriculture and Nutrition (GODAN) initiative. Ms. Adams has worked on international agricultural issues for over 10 years, having traveled extensively including serving in Afghanistan for over a year, and has supported high-level USG leadership including members of Congress, U.S. Ambassadors, and U.S. Cabinet officials. Ms. Adams earned a Master of Science degree in Agricultural Economics from the University of Illinois at Urbana-Champaign. Her Bachelor of Science degree in International, Resource, and Consumer Economics was also from the University of Illinois at Urbana-Champaign.

Neena Anandaraman, Veterinary Science Policy Advisor

Dr. Neena Anandaraman joined the Office of the Chief Scientist in 2014 as the Senior Advisor for Animal Health Production and Products. In this role, she coordinates scientific collaboration and planning on high priority emerging animal health agricultural issues. Her focus is on zoonotic infectious diseases - those that can be transmitted between humans and animals -- including antimicrobial resistance and biosecurity. Her work provides science-based advice to senior leadership to help inform their policy decisions.

Dr. Anandaraman served as Team Lead for the Prevention and Control Team in the Applied Epidemiology Staff in the Office of Public Health Science (OPHS) at the Food Safety and Inspection Service (FSIS). She is a veterinary epidemiologist and has been evaluating zoonoses issues for OPHS since 2001, focusing on foodborne conditions, especially Salmonella and antimicrobial resistance for their impacts on pre-harvest and post-harvest food safety. She served as a Supervisory Veterinary Medical Officer in the Office of Field Operations of FSIS in Arkansas before joining OPHS.

Prior to joining USDA, Dr. Anandaraman worked at a mixed animal veterinary practice in Texas. She received her Doctor of Veterinary Medicine from Texas A&M University, and her Master of Public Health from Tulane University. Dr. Anandaraman is a Diplomate of the American College of Veterinary Preventive Medicine.

Rena Bannister, Administrative Assistant

Ms. Rena Bannister joined the Office of the Chief Scientist in January 2015 as the primary Administrative Assistant. Ms. Bannister advises the Director and team of Senior Advisors of complex administrative processes and provides support in business greetings, executive correspondence, budget matters, procurement, personnel, data processing, travel, time keeping, program record-keeping, and report production. She is an expert on the policies and procedures for the development of issuances and other reports that are important across the Department. Ms. Bannister takes pride in serving as the first point of contact for callers to the Office, who may include Members of Congress, members of Congressional committee staff, White House officials, USDA executives and staff, high level executives from other Federal Departments and agencies, leaders of special interest groups, and members of the public. Ms. Bannister has received numerous awards for her administrative work since her first position in government service in 1984. She attended the University of Maryland University College from 1998-2004 and is currently pursuing a Bachelor of Science degree in Technical Management from Embry Riddle Aeronautical University. Ms. Bannister is passionate about working with others, creating a collegial atmosphere at work, and performing office operations at a high level.

Peggy R. Biga, Senior AAAS Science and Technology Policy Fellow

Dr. Peggy R. Biga joined the Office of the Chief Scientist in 2019 as the AAAS Science and Technology Policy Fellow. In this role, she hopes to work with USDA representatives to the National Science and Technology Council (NSTC) of the White House and to coordinate Department activities related to animal health and production, and supports USDA’s role in policy related to childhood nutrition.

Dr. Biga has a strong interest in developing solutions to issues at the intersection of human nutrition and the environment. She designed and conducted original research in comparative physiology, including studies analyzing the role of maternal nutrition on offspring growth and development. She has worked closely with international scientists, managed student-led science projects, taught biology and evolution to undergraduate and graduate students, and managed a science outreach program devoted to enhancing STEM exposure to underrepresented middle-school kids. Her areas of technical expertise include: comparative physiology and endocrinology, nutritional physiology, developmental biology, aquaculture, and epigenetics.

With a passion for public service and inclusiveness in academia, she has been involved in Women in STEM groups at the University of Alabama at Birmingham and North Dakota State University. She actively engages in science outreach and education, working with diverse audiences through mentorship, publications, and presentations. As a member of the Education and Workforce Training Committee for the Birmingham city Mayor, Peggy helped developed strategies for enhancing access to quality K-12 education and resources for workforce training.

Dr. Biga received her Ph.D. from the University of Idaho, and completed post-doctoral training at the Marine Biological Laboratory and the Great Lakes WATER Institute at the University of Wisconsin-Milwaukee. Her research in comparative biology has been supported by the National Institutes of Health and the United States Department of Agriculture (NIFA).

Elizabeth Hill, USDA Honey Bee and Pollinator Research Coordinator

Elizabeth Hill is the USDA Pollinator Coordinator for the Office of the Chief Scientist (OCS). In this role, Ms. Hill promotes collaboration and communication across USDA agencies, the managed pollinator industry, and relevant USDA grant recipients. Further, she strives to ensure that USDA initiatives support the pollinator health goals set forth by the Pollinator Health Task Force. Since 2016, Ms. Hill has served as Agricultural Economist in the Office of the Chief Economist’s Office of Pest Management Policy, where among other duties, she examines the interface between the needs of agricultural pest management and pollinator protection. Further, in this role she supports development and registration of pest management tools for beekeepers in combatting honey bee pests. Prior to joining USDA, Ms. Hill worked on pest management and pollinator initiatives with the Environmental Protection Agency and on agricultural and beekeeping programs as an Agricultural Extension Agent with the University of Maryland.

Ms. Hill’s primary research interests include Integrated Pest Management (IPM) for managing pests of honey bees and advancements in biological controls to support IPM strategies. An avid beekeeper, Ms. Hill is deeply engaged in the beekeeping community as a producer, educator, and through nonprofit and state beekeeping association board service. She has led educational, outreach, and citizen science initiatives, and has been both a recipient and panelist on numerous research grant programs. Ms. Hill earned a Master of Science degree in Environmental Economics and a Graduate Certificate in Conservation Ecology and Sustainable Development from the University of Georgia, where she focused on conservation land use policy.

Laura Schreeg, Advisor for International Affairs

Dr. Schreeg joined the Office of the Chief Scientist in July 2019. She comes to OCS from the United States Agency for International Development (USAID) Bureau for Food Security, where she served as a technical advisor and program manager for the implementation of the Global Food Security Strategy (GFSS). Laura worked with field programs, donors, and the private sector to sustainably increase income for small farms. Her work helped to improve nutrition and strengthen food security in developing countries. She coordinated the development of the GFSS technical guidance series and worked with stakeholders to advance evidence-based policy. Her work focused on Africa and expanded the impact of research investments and increased beneficial technologies available to producers, processors and others in agriculture.

Dr. Schreeg was awarded a prestigious Science and Technology Policy Fellowship by the American Association for the Advancement of Science (AAAS). She was a postdoctoral research assistant at Brown University and the Marine Biological Laboratory. She received her PhD in Interdisciplinary Ecology from the University of Florida, with a concentration in Soil and Water Science. Her dissertation research was conducted in Panama with the Smithsonian Tropical Research Institute. She served as a Peace Corps volunteer in the Andes of Ecuador after she earned a Master’s degree from Michigan State University and a Bachelor’s degree from Saint Mary's College. She grew up in Indiana.

William C. Trenkle, Departmental Scientific Integrity Officer (DSIO) / Research Integrity Officer

Dr. William Trenkle joined the Office of the Chief Scientist in January 2018 as the Senior Advisor on Scientific Integrity and Departmental Scientific Integrity Officer for the U.S. Department of Agriculture (USDA). In this role, he will help to develop Department-wide policies on scientific integrity, administer USDA’s scientific integrity program, and provide oversight of responses to resolve scientific integrity concerns. He also serves as the principal advisor to the Under Secretary for Research, Education, and Economics on scientific integrity matters.?

Dr. Trenkle comes to OCS from the Division of Investigative Oversight (DIO), Office of Research Integrity (ORI), HHS, where he was the Acting Division Director for DIO and had previously served as the Acting Division Director the Division of Education and Integrity (DEI), ORI. Prior to ORI, he served as the Director of the Chemical Biology Core Facility in the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, as a Program Director with the Division of Pharmacology, Physiology and Biological Chemistry in the National Institute of General Medical Sciences (NIGMS), NIH, and was on the Chemistry faculty at Brown University. Dr. Trenkle has expertise in the forensic analysis of scientific imagery and was appointed to the NIST Organization for Scientific Area Committees (OSAC) for Forensic Science as an inaugural member and Vice-Chair of the Video/Imaging Technology and Analysis (VITAL) Subcommittee. The VITAL Subcommittee is working on the development of national standards and guidelines related to the forensic application of technologies and systems to capture, store, process, analyze, transmit, produce and archive images.

Dr. Trenkle was an NIH National Research Service Award (NRSA) postdoctoral fellow at Harvard University, received his Ph.D. from the University of California, Irvine and his Bachelor of Science degree from Alma College.

Paul Zankowski, Senior Advisor for Plant Health & Production and Plant Products

Dr. Paul Zankowski joins OCS on Oct 1, 2017, as incoming Sr. Advisor for PHPPP, bringing over 30 years of experience in plant sciences from basic to applied.?He joins OCS on detail from USDA’s Agricultural Marketing Service/Plant Variety Protection Office (AMS/PVPO), where he has served as PVPO Commissioner since 2001.?As PVPO Commissioner, Dr. Zankowski worked with public- and private-sector U.S. and international plant breeders to protect their new innovative varieties through the U.S. PVP system.?He has collaborated with entities including the U.S. Patent and Trademark Office, the American Seed Trade Association (ASTA), Seed Association of the Americas (SAA), Association of University Technology Managers (AUTM), USDA ARS Office of Technology Transfer, Association of Official Seed Certifying Agencies (AOSCA ),and the International Union for the Protection of New Varieties of Plants (UPOV), as well as other country’s PVP offices, on plant breeder’s rights issues.?Most recently, he has been actively involved in a joint working group comprised of scientists from ASTA and the PVP Advisory board, on developing an effective molecular marker protocol for distinguishing plant varieties, as a distinction basis that can be internationally accepted.

Prior to joining the USDA, Dr. Zankowski held the positions of? Director of Biotechnology, Vice President of Research, Biotechnology Manager, Associate Director of Science & Technology, and Cell Biologist, for Harris Moran Seed Company in San Juan Bautista, California, working on improving fruit and vegetable varieties since 1988.

Paul conducted post-doctoral research in plant biotechnology at Advanced Genetic Sciences (Oakland, CA) in 1987 and the ARCO Plant Cell Research Institute (Dublin, CA) in 1986, and received Ph.D. and M.S. degrees in Plant Physiology from the University of California, Davis and a B.S. in Biology from Penn State University.