Joseph P. Ardizzi, Ph.D., Cornell University.
My research interests are in the areas of cell biology and development. As a microbial geneticist, I am pursuing two lines of research using the fungus Neurospora tetrasperma. One line involves the role of microtubules and related structures; the other, the genetic components of sexual phase development.

The movement and positioning of nuclei within cells is dependent on microtubule­associated components. To identify these components and to define their roles genetically, I am analyzing the process of nuclear division and ascospore formation using mutants resistant to antimitotic agents.

Other mutations that affect development in the sexual phase of Neurospora tetrasperma have been isolated in the laboratory. Cytological and genetic methods are being used to characterize the developmental stage affected by each mutant and to construct a developmental pathway consistent with the behavior of the mutants.

By combining these separate approaches, I hope to: (1) identify genetically individual microtubule system components, (2) determine the role in development of each of these components, (3) examine the relationships between these mutations, and (4) describe the developmental pathway determined by the genes.

Kris Brubaker, Ph.D., The Pennsylvania State University
Prostate cancer (CaP) is one of the leading causes of death in men. Even though it is a slow growing cancer (in most instances), eventually it spreads to other organs including bone. Once in bone, the cancer is able to change the dynamics of bone remodeling favoring bone formation. I am interested in the mechanisms involved in the stimulation of bone formation by CaP. Some of the factors which I have studied during my post-doctoral fellowship at the University of Washington are the Bone Morphogenetic Proteins (BMPs), RANKL, OPG (osteoprotegerin), Cathepsin K, Runx2 and estrogen.

Runx2 or Cbfa1 is a transcription factor cloned from osteoblasts and is pivotal in regulating expression of factors involved in bone remodeling such as collagen type I, OPG, osteocalcin and bone sialoprotein. This transcription factor is regulated by members of the bone morphogenetic protein family. I have found that Runx2 is expressed in CaP and is transcriptionally active in several CaP cell lines. PC-3 is a CaP cell line isolated from a bone metastasis which has high levels of Runx2 protein. Recently, I observed that BMPs stimulate PC-3 to express OPG. Therefore, I am interested in the mechanism(s) involved in the regulation of Runx2 expression in CaP through promoter studies. 

George P. Chamuris, Ph.D., State University of New York, College of Environmental Science and Forestry at Syracuse
My research interests are centered on the ecology of wood-, bark-, and litter-inhabiting fungi. I am interested specifically in the biology of fungi inhabiting the bark of living trees, as well as their microbial, invertebrate, and plant associates on the bark surface. Further research is needed in the areas of colonization, spore germination and fungal-invertebrate (tardigrade and rotifer) interactions. I have also studied, in collaboration with Dr. Emeric Shultz in the Department of Chemistry, the degradation of suberin by bark fungi. This topic also needs to be investigated further.

Currently I am investigating the decomposition of forest litter by fungi and invertebrate detritivores (particularly the Collembola). Topics of possible research in this fascinating area of community ecology are diverse and open to exploration. If you have an interest in botany, microbiology, biochemistry or ecology, contact me so that we may discuss possible research projects.

Clay E. Corbin, Ph.D., Ohio University
My research interests are in community ecology, evolutionary morphology and conservation biology. I am particularly interested in addressing the following questions: What factors (i.e. historical, local ecology) are important to animal community membership and the behavioral and morphological diversity seen in a community? What evolutionary innovations have facilitated the persistence or evolutionary radiation of a group of organisms? Does evolution in convergent groups occur along the same ecological pathways?

In past research, I set out to compare and contrast the patterns of macroevolution within and among flycatcher clades of the world. To do this, I characterized species’ relative positions in space using measurements on the morphology and foraging behavior for 632 species of Old and New World flycatchers. Three major findings serve as springboards for future work.

First, in regional communities of flycatchers in Ohio, Arizona and Southern Africa, there is a significant positive relationship between the morphology and foraging behavior in Old and New World flycatchers. Furthermore, the functional ecomorphological relationships are concordant between North American and Southern African communities. For example, longer legged birds utilize the ground during foraging more than shorter legged counterparts. Also, birds with wider bills tend to hawk for insects more than birds with narrow bills. Mine is the first test of ecomorphological concordance among flycatcher communities while considering the phylogenetic relationships among the community members.

Second, if morphological evolution is modeled as a Brownian process, one may expect disparity to have a linear relationship with time since origin for phylogenetic groups. In the three largest clades of flycatchers on the planet, this relationship is not linear. Over- or under-dispersed monophyletic groupings tend to offset the expected relationship. One interesting thing about these flycatcher groups is that 80% of the monarch flycatchers are found on islands while only 8% of the 400 species of New World tyrant flycatchers are island species. So, despite the ecological dominance of the tyrants in the New World, their morphological diversity has been outpaced by that of the monarchs. The vicariant island history of the Monarchs may be the dominant factor in the adaptive radiation of these birds. Also, this would reinforce the idea that an adaptive radiation is not necessarily associated with large numbers of organisms. In any respect, the monarch flycatchers are an evolutionary system that needs further study in ecological, morphological and systematic arenas.

Third, is there a particular ecological axis partitioned during the evolutionary radiation of a group of organisms? Furthermore, is that axis common between convergent groups (i.e. Old and New World flycatchers, warblers, finches, etc.)? In the flycatchers, the three independent groups have diversified along a habitat axis first and second, along a dietary axis. This scale may be too large. To wit, the axis of diversification in older groups is not always maintained by younger subclades. Hence, phylogenetic constraints are not universal within the world's flycatcher groups.

Other research has included the studies on the environmental influences on foraging behavior and habitat preference. In one study, I asked if competition structured interior forest bird communities. Another study examined the relative similarities between migrant songbirds and the resident communities (tropical vs. temperate) they visit every year. Most recently, I have been exploring the effects of different forest management techniques such as prescribed burning and thinning on foraging behavior and community membership of bird communities in southern Ohio. Future work will combine those interests above with issues pertaining to human land use practices.

George T. Davis, Ph.D., University of Illinois at Urbana-Champaign
Most traits of agronomic importance in crop species including maize are polygenic in nature, i.e. they are affected by several genes. Such traits include size, kernel composition, days to flowering, germination vigor, etc. The loci that affect polygenic traits are called quantitative trait loci (QTL). QTL analysis is the means whereby one determines the relative significance of particular loci with regard to a particular polygenic trait.

The overall theme of my research is the determination of the relative contribution of genes to polygenic characters of agronomic, biochemical, or physiological interest. My past research focused on QTL associated with endosperm starch and protein levels in maize. Using molecular methods, I have established a genetic data set on 90 families of maize, and am interested applying it to identification of QTL associated with characters such as growth rate, herbicide resistance, disease resistance, heat tolerance, nitrogen use efficiency, etc.

In the future, I would like to expand my research to include molecular analysis of other plant, animal, and fungal species.

Carl A. Hansen, Ph.D., Milton S. Hershey Medical Center, Pennsylvania State University
The ability of cells to respond to their environment depends on types of signaling pathways that are present. It is now estimated that more than 60% of all signaling pathways involve a heterotrimeric G protein coupled to a seven transmembrane spanning receptor. These “so called” G protein coupled receptor (GPCR) signaling pathways respond to physical and chemical cues to regulate nearly every aspect of bodily function, from the perception of light, smell, and taste to the regulation of growth, development, metabolism, cognition, and locomotion. GPCR-signaling pathways require the sequential interaction of 3 proteins: a 7 transmembrane receptor that receives a physical or chemical signal from extracellular milieu; an effector, which may be an enzyme or ion channel, that produces a change in the intracellular milieu to bring about the appropriate cellular response; and a heterotrimeric G protein that mediates the communication between the receptor and effector.

One of my major research directions is to understand the role of heterotrimeric G proteins in assembling and maintaining fidelity in these signaling pathways. G proteins are heterotrimers composed of abg subunits. Molecular cloning has revealed 16 a subunits, 5 b subunits, and 12 g subunits, yielding the potential to assemble nearly 1000 structurally distinct G proteins that can be utilized for directing the fidelity of different signaling pathways.

A second major focus of my research is to understand how signaling pathway regulate development and growth in the vertebrate heart. Many different signals contribute to the induction of cardiac hypertrophy (growth), which can result in either adaptive hypertrophy, as with exercise, or pathological hypertrophy, as with aortic stenosis. Of the many signals that regulate heart function, activation of  a ₁-adrenergic receptors (AR) by catecholamines is an important initiator of the hypertrophic response and culminates in genetic and morphologic changes in the heart.

John M. Hranitz, Ph.D., Mississippi State University.
The overall approach of my research has been to integrate field and molecular biology to study the ecological genetics and physiological ecology of amphibians and reptiles. I have been investigating the population genetic structure of amphibians and reptiles to assess the roles that genetic drift and natural selection have in the evolution of populations.

One aspect of my research is aimed at using the population genetic structure of a collared lizard population to describe patterns of dispersal in the central part of the species' range. With colleagues from the University of Central Oklahoma and Oklahoma State University, I am investigating the levels of genetic divergence obtained from uni-parental and bi-parental genetic markers to evaluate age- and gender-biased patterns of dispersal among the five study sites in this population. I am also evaluating the efficacy of these markers in parentage analyses that we intend to use to investigate factors that influence reproductive success collared lizards.

In other areas of my research, I have collaborated with numerous faculty in investigations of invertebrates by providing some level of technical expertise in genetics or the detection and measurement of stress proteins. My collaboration with graduate students and faculty at Bloomsburg University involves studies of the population genetic structure of pelagic gooseneck barnacles. In another ongoing collaboration with a faculty member from the University of Central Oklahoma, we are studying the thermotolerance of invasive solitary bees in the western United States. Undergraduate students have worked closely with me to conduct skeletochronological studies of the age-structure of island and mainland toad populations, studies of isozyme expression in tissues of collared lizards, pcr-based genotyping in lizards, and measurement of stress proteins in bees and frog tadpoles. Graduate students have worked with me to develop skills that allowed them to independently investigate the behavior, ecology, and genetics of cricket frogs, solitary wasps, and collared lizards.

As I develop a research program at Bloomsburg University, I plan to continue to integrate field and molecular biology by building a research program in which natural history, evolution, and ecology provide the broader context for my research into amphibians and reptiles, and field and molecular biology are the tools for testing hypotheses and obtaining answers to deep-seated questions about amphibians and reptiles.

Judith Kipe­Nolt, Ph.D., The Pennsylvania State University.
Legumes such as beans, peas and alfalfa form a nitrogen­fixing symbiosis with soil bacteria of the genus Rhizobium. One aspect of my research is aimed at increasing our understanding of and improving this symbiosis to decrease the need for inorganic nitrogen fertilizers. I have a large collection of bean Rhizobium strains from many parts of the world and am examining the coevolution of host plant and bacteria. Characteristics that may determine survival and competitiveness of a given bacterial strain are being studied, and plant genes that confer Rhizobium specificity are being sought.

A second area of research, that I am doing in collaboration with the Soil Conservation Service of USDA and county Conservation Districts, involves the potential use of composting to lower groundwater pollution from manure. Graduate and undergraduate students are involved in studies on compost production and comparing effects of manure, compost and mineral fertilizer applications to crops and soils.

Thomas Scott Klinger, Ph.D., University of South Florida
My area of expertise is marine biology, with a research focus on the functional aspects of invertebrate zoology. Most of my research investigates physiological, behavioral, and ecological aspects of nutrition.

I have most recently been investigating manufactured feeds suitable for mariculture of sea urchins. These studies have encompassed both development of a foundation for the aquaculture of echinoderms and studies in fisheries ecology. I have also had a continuing collaboration with faculty from the University of Queensland in a study of the community ecology of the Great Barrier Reef. My contribution to this study has examined resource utilization and niche partitioning among sea cucumbers inhabiting reef flats and lagoons. Other ongoing projects include studies of digestion in echinoderms and an investigation of physiological adaptations of digestive enzyme complements of Antarctic Echinoderms. Students working in my laboratory have also investigated the role of disturbance in structuring marine communities, nutrient allocations during regeneration, competition among co­occurring species of fiddler crabs, population structure in island habitats, and gene flow among isolated populations of Pacific barnacles.

Mark S. Melnychuk, Ph.D., Kent State University.
My current research focuses on how phosphate and nitrate concentrations in Fishing Creek vary during periods of precipitation and/or the thaw of snow and ice packs, and during periods lacking these events. Analyses include determination of dissolved phosphate. Variations in the concentration of these pollutive chemicals in Fishing Creek is significant with respect to their loading into the Susquehanna River and the Chesapeake Bay.

Other recent research investigated cellular responses by host rats due to varying infection sizes of the intestinal parasite Hymenolepis diminuta. Past research has studied how diet or hormonal status of host rats influences the reproduction of H. diminuta.

James E. Parsons, Ph.D., Ohio State University.
My primary interest at this time is the development and implementation of miniaturized laboratory testing into the clinical laboratory.

Clinical microbiology and/or epidemiology related problems that network between public health organizations, the clinical laboratory, and the public are also of interest. I would encourage field work in the area of epidemiology.

Steven T. Rier, Ph.D., The University of Louisville.
My overall research interests encompass many aspects of stream ecology and the ecology of other shallow freshwater ecosystems such as wetlands and the near-shore zones of lakes.  I am currently interested in the role that microorganisms such as algae, bacteria, and fungi play in the carbon and inorganic nutrient dynamics of streams and how human impacts can alter these dynamics. Examples of past research include investigating how nitrogen, phosphorus, light, and dissolve organic matter (DOM), control the productivity of attached algae and bacteria and how these two groups of organisms interact with each other under different environmental conditions. I am currently conducting research into how algae growing on surfaces in streams might facilitate the decomposition of organic matter and remineralization of nitrogen and phosphorus through influencing the activity of extracellular enzymes that originate from heterotrophic bacteria and fungi.

I am also interested in how rising levels of atmospheric carbon dioxide might indirectly influence stream ecosystems. Streams can depend on inputs of terrestrial leaf litter for up to 99% of the carbon needed annually to sustain the ecosystem. When trees grow in an atmosphere containing elevated carbon dioxide the leaf litter shed in fall is potentially more resistant to decomposition and subsequent incorporation into stream food webs. I have been involved with several studies investigating the consequences of these alterations to the stream ecosystems mainly from microbial perspective.

Cynthia A. Surmacz, Ph.D., Milton S. Hershey Medical Center, Pennsylvania State University.
The incidence of heart disease in women increases dramatically following menopause, an effect attributed to a reduction in estrogen levels. However, few studies have focused on the risk factor changes in this population.

My current research examines how plasma lipid levels, including total cholesterol, high density lipoproteins, low density lipoproteins, and triglycerides, are altered by menopause. Also under consideration are the effects of menopause on lecithin:cholesterol acyl transferase, an important plasma enzyme active in reverse cholesterol transport. The data obtained from these studies will be used in future experiments to examine such variables as the effects of exercise, estrogen replacement therapy, diet and body composition.

These studies are conducted in collaboration with Dr. Margaret Till, a physiologist in the Department of Biological and Allied Health Sciences and Dr. Swapan Mookerjee, an exercise physiologist in the Department of Health, Physical education, and Athletics. Facilities to conduct these studies are available in the physiology research lab in Hartline Science Center and in the Human Performance Lab in Centennial Gym.

Margaret Till, Ph.D., Auburn University.
My research interests are now centered on cholesterol metabolism and factors influencing it. Our lab has been involved in two lines of research, effects of exercise on plasma lipid levels and studies of plasma lipids in post­menopausal women. The exercise studies have been conducted in young women and look at the effects of aerobic and resistive exercise in modifying plasma lipid levels.

Dr. Surmacz and I have just completed a four year study of changes in women's plasma lipid profiles, health behaviors, and risk factors for cardiovascular disease. The study covered women of college age, young to middle age women, postmenopausal women, and postmenopausal women taking hormone replacement therapy. Several students have been and are involved in these studies as they pursue their thesis research for the masters degree or undergraduate independent research projects.

Currently, we are examining acute changes in lipid metabolism of young women after aquatic exercise at 40 and 60% of their maximal oxygen utilization. This study continues Dr. Surmacz and my long standing collaborative efforts with the exercise physiologists in the Department of Health, Physical education, and Athletics. Presently we are collaborating with Dr. Mookerjee and graduate students.

Gary T. Wassmer, Ph.D., University of Delaware
I am interested in how animals can tell the time of day and the time of year, and how their behavior and physiology changes during the day and during the year. My studies focus on identifying the location of this clock or calendar within the body, understanding how the timing mechanisms work, and determining how the timing systems help the animal adjust to temporal changes in the environment.

Most recently I’ve been involved in two projects. First, I’ve been investigating the effects of gravity on the biological timing system of various desert beetles. These studies are aimed at identifying changes in the biological clock associated with space flight - and hopefully preparing a strategy to allow humans to work more efficiently in microgravity. A second project I’ve just begun looks at the effect of gender on seasonal patterns of growth and development. For these studies I use the woodroach Parcoblatta pennsylvanica . This interesting animal is the only roach in the Americas that is able to spend winters outside (rather than cohabitating with humans). I’ve observed that males and females appear to respond differently to environmental cues that signal that spring is coming. I’m currently trying to confirm these casual observations and delineate gender specific responses to daylength. Eventually, I hope to relate these patterns (if there!) to gender differences in reproductive strategies.

Kevin J. Williams, Ph.D., Syracuse University

Marianna D. Wood, Ph.D., University of Kansas
My major research focus is the behavioral ecology of chipmunks, squirrels, and other forest-dwelling small mammals. Chipmunks and squirrels are excellent subjects for behavioral research because they are active during the day and, therefore, can be easily observed. On-going research projects include observations of intra- and inter-specific interactions to determine if and how small mammals partition shared habitat. I am also interested in quantifying microhabitat selection and determining which small-scale features are necessary or desirable in an animal's home range. I also am studying the relationships between small mammals and other community members, including plant species that are used for food and other organisms that are potential resource competitors.

In addition to mammalian behavioral ecology, I am interested in a wide variety of ecological topics. For example, I am currently monitoring a local source of acid mine drainage and its effects on a small watershed.

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Last updated on 29 September 2003.