Stephen Cessna

Plant Stress Physiology and Cellular Biochemistry

Plants in nature are continuously subject to several environmental insults, including drought, heat, cold, toxic pollution, disease, and insects. While some plants have evolved the ability to specifically combat one or more of these stresses, (as cacti have special abilities to withstand drought), all plants have adaptive ability to tolerate most stresses to varying degrees. This is achieved at the cellular level by the transcription of specific stress-activated genes. My research project focuses on the roles of calcium and hydrogen peroxide in activating these stress-activated genes. Students working on this project may have the opportunity to learn several different laboratory techniques including: greenhouse maintenance of unique plants, plant cell culture, luminometry, fluorimetry, fluorescence microscopy, and plant genetic manipulation.

Physical Biochemistry of Serum Albumins

Albumin, the most prominent protein in blood serum, is believed to transport fatty acids, drug compounds, vitamins, and toxins through the blood stream. We use fluorescence spectroscopy to determine how well small molecules bind to serum albumin. The small molecules we are currently testing are the B vitamin folic acid and an herbicide called 2,4-D. These studies have relevance to the fields of nutrition and toxicology.

Clair Mellinger

Bird Banding

Northern Saw-whet Owls (NSWO) are known as breeding birds of the boreal forests in northern US and Canada. Although some observers observed migration in NSWOs many years ago, it has only been in the last 20 years that banding research has firmly established this phenomenon and clarified the pattern and dynamics of that migration. In the fall of 2001 I established a banding station at Highland Retreat Camp for the purpose of monitoring the migration of Northern Saw-whet Owls in western Virginia. The only other saw-whet banding station in Virginia at that time was on the eastern shore of Virginia. In 15 nights of banding that first year I caught and banded 122 owls, including six that were previously banded at other banding stations north of us. Since then I have continued the banding each fall (basically November) with similar but variable results. This station has become a part of a loose network of banding stations known as Project Owlnet. Our goals are to establish the route, timing, and variability in NSWO migration. We are also studying differential migration between genders and age groups along with other amenable research topics. There are several dozen NSWO migration banding stations and recapture and recovery of banded birds is adding quickly to our knowledge of its basic biology. Students are welcome to and participate in this research in various ways.

Roman Miller

Reproductive Endocrinology and Function

My major research focuses on factors that influence the development and function of reproductive tissue. Currently we are investigating the influences of neonatal exposure of phytoestrogens (estrogen-like compounds naturally found in some plants) on subsequent development and function of mouse male and female reproductive systems, including ovary, uterus, testis, epididymis, prostate and seminal vesicle structure and function. The responses of polyamines and epidermal growth factor to estrogenic influences are of special interest. Participating students learn techniques in animal handling and surgery, histology, biochemical tissue assays, histochemistry, and morphometry.

Bioethics

A second research area considers the insights that Anabaptist theology bring to contemporary processes and issues in bioethics. Of special interest are the ideas of virtue ethics and issues involved in the commencement of life.

Doug Graber Neufeld

(Currently on sabbatical/leave-of-absence at the Royal University of Agriculture, Phnom Penh, Cambodia)

Environmental Toxicology and Biomonitoring

My research projects focus on the physiological mechanisms of animal exposure to toxic compounds in their environments, with a focus on invertebrates (insects and clams). I have two recent research projects that my research students have participated in. One project measured mercury levels in the Asiatic clam in the South River of the Shenandoah valley, which suffers from elevated concentrations due to industrial release. We measured the ability of clams to accumulate this pollutant, with the goal of using these animals as biomonitors. This study, in collaboration with researchers from JMU and state agencies, has provided information on which sections of the river have higher levels of mercury contamination. The second project, funded by the Jeffress Memorial Trust, focused on the renal excretion of toxic compounds (such as pesticides and plant alkaloids) in insects. We demonstrated the presence of multispecific transport mechanisms that are capable of moving a variety of relevant compounds out of the blood into the urine of insects. We believe that this mechanism may play an important role in resistance to toxin exposure by insects. These projects fall within my broader interests of environmental physiology-the study of how animals survive in their diverse environments, how that physiology is altered by environmental contaminants, and how this information can be utilized for monitoring of environmental impacts.

Jim Yoder

The Spread of Invasive Exotic Plant Species and Their Impact on Rare Plant Populations in Shenandoah National Park

In the spring of 2006 I began a 3-year collaborative study working with Shenandoah National Park research botanist, Wendy Cass. The project includes both intense on-site field surveying and mapping and analysis of exotic plant spread and impact using a Geographic Information System (GIS) by myself and undergraduate research students. The project addresses two specific research questions that focus on the exotic plants invading the Shenandoah National Park: 1) What is the rate of spread of the three most threatening exotic species beginning to invade the Big Meadows Swamp Natural Heritage area and 2) What is the impact of these exotics on the continued viability of the eight rare plant species located within the area? Both of the questions are of intense interest to park biologists and land managers as well as contribute to the broader ecological study of exotic plant invasions of native ecosystems. Data collected will be used for detailed analysis of rare plant populations as well as development of spatial population and threat models using GIS. These models may be useful to predict future spread of exotics and subsequent impacts on ecologically sensitive areas within the park and throughout the region.

Matthew Siderhurst

Insect Chemical Ecology

Chemical signals are among the most used information transfer sources in ecology and they can include pheromones (conspecific signaling), plant-herbivore interactions, and predator-prey interactions. While many of these chemical signals are of basic scientific interest, they are also increasingly important to developing ecologically rational pest control strategies, both as replacements for pesticides against established pests and to help mitigate the increasing threat of invasive species (damage ~$137 billion/annually). My research focuses on arthropod chemical ecology, applying the tools of organic chemistry to ecological interactions. Currently I am collaborating with colleagues in Hawai’i on research involving attractants for tephritid fruit flies (direct costs to Hawai’ian agriculture ~$15 million/annually, lost markets ~$300 million/annually) and the nettle moth, Darna pallivitta. I am in the process of initiating a research program in which I hope to include undergraduates with interests in chemical analysis and synthesis, and students with interests in ecology and/or organismal biology.