A stem cell is an undifferentiated cell of a multicellular organism that is capable of giving rise to indefinitely more cells of the same type and from which certain other kinds of cell arise by differentiation. At Kentucky State University’s College of Agriculture, Food Science, and Sustainable Systems, Dr. Tyra Dunn-Thomas is conducting research that focuses on the effects of pesticide exposure on stem cells as a model for human health. Specifically, Dr. Dunn-Thomas is interested in the mortality rate and differentiation of cells once exposed to pesticides.

Stem cells have the potential to develop into many different cell types in the body during early life and growth. Additionally, in many tissues these cells serve as a sort of internal repair system, dividing essentially without limit to replenish other cells as long as the person or animal is alive. When a stem cell divides, each new cell has the potential either to remain a stem cell or become another type of cell with a more specialized function.

growth. Additionally, in many tissues these cells serve as a sort of internal repair system, dividing essentially without limit to replenish other cells as long as the person or animal is alive. When a stem cell divides, each new cell has the potential either to remain a stem cell or become another type of cell with a more specialized function.

Dr. Dunn-Thomas has a background in biology, computer science, and clinical research. She has more than 12 years of research experience working in academia, industry, and government, and her research has included Parkinson's disease, cancer, retinal development and diseases, women's health, post-traumatic stress disorder, genomics, and proteomics.

31

Research investigates livestock emission using eddy flux covariance

Agricultural soils are ecologically complex systems and their management could impact rate and magnitude of gas and energy exchange between the surface and the atmosphere. Dr. Maheteme Gebremedhin, assistant professor of soil science in the College of Agriculture, Food Science, and Sustainable Systems employs the micrometeorological technique of eddy flux covariance to understand the temporal variation of carbon dioxide and methane gases exchanges on grazing pasture and forest landscape.

Measurement of livestock emission is central to projections and uncertainties related to studies of animal methane emission in responses to grazing pattern and management. The goal of Dr. Gebremedhin’s project is to estimate methane emission rate from a goat pasture, developing a fuller understanding of the variables controlling the temporal dynamics of methane fluxes across temporal scales ranging from seconds to seasons and beyond. Measurements also include high frequency 3-D wind speed and direction, air pressure, temperature and humidity, precipitation and photosynthetically active radiation (PAR) and incoming and net radiation.

Dr. Gebremedhin is also working in soil science to understand the effects of farming practices and soil management on soil health and productivity. His research aims to understand innovative conservation practices such as minimum tillage, cover crop, and crop rotation on physical, biological, and chemical properties of soils.

He and his research team work closely with farmers, particularly small-scale land owners, and provide relevant findings of their research in key crop production restraints that Kentucky farmers are confronted with: excessive nutrient runoff, organic carbon content, and altered composition of soil biota.

Currently, Dr. Gebremedhin and his research team are working on a project funded by the U.S. Department of Agriculture Natural Resources Conservation Service aimed at understanding the effects of manure application and cover crop on soil physical, chemical, and biological properties.

32