A pseudo-broad beam approach to low-LET radiation biology studies using an electron microbeam. BENJAMIN ARTHURS (Washington State University Pullman, WA 99163) MARIANNE SOWA (Pacific Northwest National Laboratory, Richland, WA, 99352)

Microbeam technology has been widely successful in studies of low-dose radiation biology. Using an electron microbeam to mimic low-linear energy transfer (LET) radiation it is possible to study the biological effects of -rays and x-rays, which contribute to background radiation exposure and carcinogenesis. By taking advantage of the scattering properties of electrons in air, one can use the microbeam in a pseudo-broad beam mode. This procedure lends itself well to low-dose explorations of genomic instability and bystander effects in mammalian cells. We have used 50 keV electrons and a 5 mm air gap to show the effectiveness of the electron microbeam in a pseudo-broad beam configuration. Using GafChromic® film we have developed a method of dosimetry allowing for accurate low-dose irradiations. Also, we have designed aluminum plates acting as shielding for measuring non-targeted bystander effects resulting from low-LET radiation exposure. The effectiveness of pseudo-broad beam irradiations in producing biological damage was determined by formation of DNA double strand breaks measured using a -H2AX foci assay. After irradiating mammalian RKO cells, we have observed an increased number of these foci above the background levels seen in unirradiated controls. These results support the use of the electron microbeam in pseudo-broad beam mode to study low dose low-LET radiation effects and their implications to cancer formation in mammalian cells.

BDE-47 Metabolism and Effects on Fecundity in Japanese Medaka (Oryzias latipes) and Fathead Minnows (Pimephales promelas). ELISABETH MUIRHEAD (University of Puget Sound Tacoma, WA 98416) IRVIN SCHULTZ (Pacific Northwest National Laboratory, Richland, WA, 99352)

Brominated diphenyl ethers (BDEs) are commonly used flame retardants in textiles, electronics, plastics and paints. Environmental concerns associated with release of BDEs has increased due to structural similarities with polychlorinated biphenyls and reported toxic effects, which include disruption of the endocrine/thyroid system. In this study, the kinetics of BDE in Japanese Medaka (Oryzias latipes), an organism that is being used increasingly as an alternative animal model for testing the chronic toxicity of chemicals, were examined, along with the effect of repeated oral exposure to BDE on reproductive performance in Fathead minnows (Pimephales promelas). Medaka and fathead minnows were orally exposed to BDE-47 by bioencapsulation in brine shrimp, Artemia sp. For the Medaka studies, a single oral exposure was administered followed by termination at specific timepoints. Pair-breeding fathead minnows were given daily BDE-47 exposures that were continued for 25 days, during which daily fecundity was measured as an indicator of reproductive performance. In Medaka studies, measurable levels of BDE-47 were detected in the carcass within 0.25 hr with peak levels occurring at 8 hrs. The body levels of BDE-47 slowly declined and were still 25% of peak levels at 624 hrs after dosing. The BDE 47 concentration-time profile was fitted to a one-compartment clearance-volume toxicokinetic model; the model-predicted values for elimination half-life was determined to be 281 hrs. In the fathead minnow reproductive study, egg laying in the BDE-treated breeding pairs stopped after 10 to 11 days. Cumulatively, the results of these two studies suggest that it will be increasingly important to predict the kinetic behavior of BDEs, as well as the effects of BDE accumulation in wildlife, to begin to consider regulatory constraints on production and use that avoids toxic overexposure.

Breeding Population Status and Nest Site Characteristics of Hawks. KELLY CLAYTON (Washington State University Pullman, WA 99163) JANELLE DOWNS (Pacific Northwest National Laboratory, Richland, WA, 99352)

Field surveys of potential nesting sites for 3 Buteo hawks and common raven were conducted on the U.S. Department of Energy (DOE) 560-mi2 Hanford Site in spring and summer 2005 to document nesting pairs on central Hanford and describe nest site characteristics. Nest sites were mapped and characteristics of nest sites (i.e., species identification, active/inactive), type of nesting structure, tree species, nest height, and aspect of nest (8 cardinal directions) were recorded. Surveys documented 4 ferruginous hawk, 10 Swainson's hawk, 14 red-tailed hawk, and 45 common raven nests that were active in central Hanford. Current survey data were also compared to survey information compiled for 1990 through 2005 to examine trends in the number of nesting birds. Nesting pairs of common ravens on the Hanford Site appear to have significantly increased over the past decade, although survey information for this species has not been consistently collected. Ferruginous hawks (a state threatened species), Swainson's hawks (a state monitor species) and red-tailed hawks appear to have experienced a slight overall decrease in the numbers of nesting pairs between the years 1990 and 2005. Ravens and red-tailed hawks, which nest primarily on electric transmission towers, preferred nesting sites at higher elevation, and ferruginous hawks nest at lower elevations on the towers. Swainson's hawk nests were found only in trees at lower elevations.

Coatings as a Variable in Acoustic Telemetry. ELIZABETH HOBBS (Truman State University Kirksville, MO 63501) RICHARD S.BROWN (Pacific Northwest National Laboratory, Richland, WA, 99352)

Scientists commonly use acoustic transmitters to conduct research on salmon. Acoustic transmitters for juvenile salmon are used for short term studies since their battery life is limited and transmitters may not stay in the salmon. Transmitters can be expelled through the suture wound, by pressure necrosis or by transintestinal expulsion. Pressure necrosis occurs when an irregular part of the transmitter rubs against the body wall, causing stress on the tissue and eventual ejection of the tag. Transintestinal encapsulation involves the encapsulation of the tag by the intestine and then evisceration through the anus. Chisholm and Hubert (1985), noted that transintestinal expulsion occurred within a 42-175 day timeframe for expulsion for rainbow trout (17.5-22.5cm in length). This research will study the effect of different coatings in relation to expulsion of transmitters. The long term study of rainbow trout,(Oncorhynchus mykiss), a model species for salmon, will monitor the expulsion rates of transmitters coated in beeswax, KISS-COTE, and also expulsion rates of a control group (tags as they are currently used in salmon research). KISS-COTE is a thin, clear coating created to provide a slick surface that is hard for barnacles and other organisms to attach. This may make encapsulation difficult and possibly prolong the amount of time a transmitter can remain free floating in the body cavity. Beeswax may prevent irritation from irregular objects on the transmitter. With less irritation, the encapsulation and possible necrosis process might slow down. Helm and Tyus (1992) found that transmitters coated in beeswax had a 3% expulsion rate, significantly less than the other coatings used in their study (paraffin wax and silicone). The long term study of the effect of transmitter coatings on expulsion rates will provide data on alternate coatings and the possible implementation of the coatings for commercial/scientific use. Also, a more precise prediction of transmitter retention in the fish will create a more accurate timeframe of when scientists can expect the tag to be expelled. This will help scientists decide whether they are tracking a fish, or just an expelled tag. This information may create a clearer picture of fish migration.

Comparison of Automated and Manual Methods for DNA Hybridization. ASHTON EASTERDAY (Santa Clara University Santa Clara, CA 95053) RICHARD OZANICH (Pacific Northwest National Laboratory, Richland, WA, 99352)

There is a great interest in the use of DNA hybridization for the detection of harmful biological pathogens. Optimizing this process is important for sensitive and rapid detection in a variety of samples. A fluidics system utilizing oligonucleotide-coupled microbeads was used to perform automated hybridizations and was compared with standard bench-top hybridization procedures at 15 and 30 minutes. Automated hybridization had greater hybridization efficiency relative to manual bench-top methods. Hybridization efficiencies of four oligonucleotides (invA, lacZ, stx1, uidA1), each complementary to a gene in Salmonella typhimurium or Escherichia coli O157:H7, were compared. Automated hybridization was 26-37% and 117-121% greater relative to manual hybridizations for stx1 and uidA1, respectively. Hybridization efficiency for invA was 2-11% greater for the manual method. LacZ had poor hybridization efficiencies for both manual and automated approaches. The total hybridization procedure time was considerably reduced when performed by the automated system. This apparatus provides a new tool for rapid and sensitive pathogen detection.

Comparison of the bioavailability of 1, 2 Diethylbenzene and 1, 3 Diethylbenzene in F344 control Rats. SUSAN HIATT (Eastern Washington University Cheney, WA 99004) KARLA THRALL (Pacific Northwest National Laboratory, Richland, WA, 99352)

The compound Diethylbenzene (DEB) is a colorless liquid that is mixture of isomers and is used as a solvent. Humans are exposed to DEB through household chemicals, such as paint thinners. Through these chemicals, DEB can come in contact with drinking water and enter the human body. The purpose of the study was to look at two isomers of DEB; 1, 2-DEB and 1, 3-DEB and compare the amount absorbed in an in vitro system using F344 rat tissue as a model for the human body. Tissues used in this study included liver, brain, fat and blood from F344 control rats. The vial equilibrium method and a gas chromatography system were used to determine partition coefficients for each sample. For the compound 1, 2 DEB the tissue to blood ratios for fat were 2.56, for liver 1.45, and for brain 1.09. The tissue to blood ratios showed that 1, 2 DEB preferred to stay in fat tissue and equally distribute between liver/blood, and brain/blood. For the compound 1, 3 DEB the tissue to blood ratios for fat were, 0.59, for liver 0.13, and for brain 0.19. Tissue to blood ratios showed that 1, 3 DEB preferred to stay in blood rather than distribute into the tissues. These are significant results due studies showing that 1, 2 DEB is neurotoxic to experimental animals, while 1, 3 DEB is not. This research suggests that one reason for this occurrence is the difference in the amount of compound reaching the tissue. To understand the structural impact, further research will be needed to evaluate metabolic and kinetic differences.

Effect of Hexavalent Chromium Uptake in Chironomus dilutus Mg. (Diptera: Chironomidae) Larvae. JESSICA DEROUSSE (University of New Hampshire Durham, NH 03824) AMORET BUNN (Pacific Northwest National Laboratory, Richland, WA, 99352)

Hexavalent chromium (Cr⁺⁶) has been listed as a priority pollutant throughout the United States, including the eastern Washington State area of the Colombia River basin. As a result of disposal of cooling water containing Cr⁺⁶ from the nuclear reactors, low levels of Cr⁺⁶ have been entering the sediment water interface of the river. In response to the contamination, Chironomus dilutus (C. dilutus) larvae were used in a seven day toxicity study to test for phenotypic and genotypic consequences occurring from Cr⁺⁶ contamination found in the form of K₂Cr₂O₇. Using 4 treatments, 8 chambers containing 420 larvae each were exposed to 0 µg /L K₂Cr₂O₇ (treatment 1), 5 µg /L K₂Cr₂O₇ (treatment 2), 50 µg /L K₂Cr₂O₇ (treatment 3), and 500 µg /L K₂Cr₂O₇ (treatment 4). Each day pH levels monitored as well as marinating a temperature range of 13-15 ^oC. The larvae were counted, and ashed for dry weight. Substrate samples > 2.0 g were, weighed, and ashed. RNA extraction preformed using standard protocol for microarray analysis. Ashed larvae, substrate, and water samples have not yet been analyzed for Cr⁺⁶. Expected outcome should show uptake of higher levels of Cr⁺⁶ affecting C. dilutus negatively both phenotypically and genotypically. Upregulated proteins expressed on microarray slides will show how the organism is responding to the different levels of toxicity. This work directly relates to the environmental cleanup and remediation being done on site as well as the rivers ecosystem and stability.

Improvements in the Isolation and Purification of Nucleic Acids and Proteins Using a Renewable Microcolumn Fluidics System. JERRAH HOLTH (Harvey Mudd College Claremont, CA 91711) RICHARD OZANICH (Pacific Northwest National Laboratory, Richland, WA, 99352)

Detection of biological substances in the environment is an important part in the defense against bioterrorism and keeping water and air supplies safe. The rapid and sensitive capture and purification of cells, nucleic acids, and proteins is necessary for these efforts. Detection systems must be transportable and automatic for work in the field and be able to process samples that are dirty and/or have targets present in low concentrations. The Biodetection Enabling Analyte Delivery System (BEADS) uses microbeads to capture and purify the desired cells, nucleic acid, or protein. A variety of bead types can be used including polymer, glass, sepharose and magnetic. The following experiments were conducted: 1) Benchtop comparison of different antibodies for capturing Botulinum neurotoxin recombinant fragment, 2) Comparison of benchtop vs. BEADS for measuring six different proteins in a single sample using a multiplex bead suspension array, and 3) Purification of nucleic acid using BEADS. Flow cytometry was used to analyze the efficiency of four primary antibodies and two fluorescent labeled, secondary antibodies to bind Botulinum neurotoxin fragment in a sandwich immunoassay. The fluidics system was also compared to the traditional benchtop method, using flow cytometry, for a six-plex protein assay to examine the time needed for the procedure and the amount of capture achieved. The final part of this investigation used Real Time Polymerase Chain Reaction and an intercalating fluorescent dye to investigate and attempt to eliminate contamination, increase capture and elution efficiency, and determine the best method for automated DNA purification. The combination of AR-4 primary antibody and Alexa 488 fluorescence bound Raz-1 secondary antibody is the most effective at binding Botulinum neurotoxin. For the 6-plex protein assay, the benchtop was shown to have a greater capture than BEADS. However, for all concentrations of protein, BEADS took less time than the benchtop with the 50 µL sample taking less than one fourth the time of the manual method. The preliminary DNA investigation showed that small pore silica beads are better for elution but the larger pores capture a greater amount of nucleic acid. These three experiments produced preliminary data that will allow further enhancement of the BEADS method.

Ligand-Independent Preformation of EGFR Homodimers Visualized Utilizing Flow Cytometric FRET Techniques. DEMETRA FARLEY (Prairie View A&M University Prairie View, TX 77448) GAYLA ORR (Pacific Northwest National Laboratory, Richland, WA, 99352)

The growth factor-induced epidermal growth factor receptor (EGFR) signal transduction pathway, which promotes proliferation and differentiation in cells of varying lineage [1,2], requires for its commencement the homodimerization of EGF receptor monomers. While dimeric association of EGF receptors is primarily invoked through ligand binding, recent studies elucidate that pre-formed EGFR homodimers innately exist at the cell surface independent of activation by ligand. Here, corroboration of this finding was achieved by illustrating, via flow cytometric fluorescence resonance energy transfer (FCET-FRET), the presence of EGFR homodimers on the surface of 184A1 cells prior to epidermal growth factor (EGF) insertion. Analysis of the molecular interactions occurring between EGF receptors before introduction of growth factor involved the fusion of EGFRs to the fluorescent labels Alexa Fluor 488 (A488) and Alexa Fluor 546 (A546) using antibodies to the ectodomains of EGFR proteins. Based on FRET theory, it was anticipated that marked energy transfer, or indirect stimulation of the acceptor molecule via donor excitation and quenching, would occur between A488 and A546 only if the fluorescently-tagged EGF receptors were less than ten nanometers apart, a distance relatively suggestive of direct intermolecular activity. Upon excitation of dually stained EGFR fusion proteins, both a slight decline in A488 emission and a considerable enhancement in A546 fluorescence were visualized, substantiating the presence of FRET in the system prior to the addition of epidermal growth factor. Perceivably, a significant proportion of pre-formed EGFR homodimers must inherently exist at the surface of cells independent of activation by ligand. While the incidence of ligand-independent EGFR homodimerization has adequately been validated, the function of pre-formed EGF receptor dimers in the overall mechanism of EGFR activity remains uncertain.

Live Cell FT-IR Spectroscopy of Macrophage Response to Endotoxin. ERIN BLOMQUIST (University of Arizona Tucson, AZ 85721) JUSTINA TAM (University of Arizona Tucson, AZ 85721) THOMAS WEBER (Pacific Northwest National Laboratory, Richland, WA, 99352)

Fourier transform infrared spectroscopy coupled with attenuated total reflectance (FT-IR/ATR) has sufficient sensitivity to identify and measure chemical alterations of a cellular system following exposure to environmental agents. In this study, FT-IR/ATR measurements of the ensuing apoptotic response to lipopolysaccharide (LPS) were investigated using murine macrophage cells (RAW 264.7) maintained on a zinc selenide (ZnSe) ATR crystal. To decrease the time required for cell attachment to the ZnSe crystal, the adhesion molecule fibronectin was used as a coating on the ZnSe crystal. This shortened the attachment time to 1 day, whereas it had previously been as long as 6 days. The conundrum surrounding fibronectin use was the fear the fibronectin would cause the cells to sit higher than 1 µm which might place them above the sensing zone of the evanescent field and hence would provide no spectroscopic signal. Results using fibronectin mirrored the results obtained from the earlier studies not employing fibronectin, thus indicating that the fibronectin coating is thin and does not cause the cells to sit more than 1 µm above the ZnSe crystal. FT-IR/ATR spectroscopy was then used to examine the spectroscopic signatures of the murine macrophages before LPS treatment and 2, 4, 6, 8, and 24 hours following LPS treatment. LPS treatment induces the activation of the macrophages to produce iNOS and COX-2, which through inflammatory pathways leads to apoptosis of the macrophage. In particular, spectral changes were apparent at 1575 cm-1, 2925 cm-1, and 1034 cm-1, indicative of alterations in cellular components Amide II proteins, lipids, and sugars, respectively. Visualization of the cell death response of the murine cells to LPS treatment also was supported through immunofluorescence microscopy imaging. Our results indicate that FT-IR/ATR spectroscopy can be used to investigate live cell responses to environmental toxins.

Mammary Epithelial Cell Survival Following Exposure to Ionizing Radiation and the Radiomimetic Bleomycin. EMILY ASHJIAN (University of Washington Seattle, WA 98105) LEE OPRESKO (Pacific Northwest National Laboratory, Richland, WA, 99352)

Bleomycin is an effective radiomimetic drug which, when administered to cells, induces DNA double strand breaks (DSBs) similar to those caused by ionizing radiation. These DSBs can be measured using the H2AX assay, as each H2AX focus represents a DSB. In order to use bleomycin in place of ionizing radiation in studies where the delivery of ionizing radiation by x-ray or charged particle microbeam is not feasible, a survival curve for bleomycin is needed. Using the MCF 10A and 184 A1 lines of human mammary epithelial cells, survival curves for doses of radiation, ranging from 0.5 Gy to 9 Gy, and bleomycin, ranging from 0.1 µg/ml to 2.5 µg/ml were created for each cell line. When the survival curves of MCF 10A and 184 A1 cells were compared, the MCF 10A cells tended to be more resistant to all doses of radiation and bleomycin than the 184 A1 cells. Both cell lines demonstrated only slight differences between the trends of the bleomycin survival curve and the radiation survival curve. Use of the H2AX assay confirmed the occurrence of DNA DSBs in the survival curve experiments, as the number of H2AX foci per cell increased with increasing doses of bleomycin and radiation. This corresponds to the decreasing surviving fraction of both MCF 10A and 184 A1 cells as the doses of bleomycin and radiation were increased. Results from this study will be used to administer doses of bleomycin to MCF 10A and 184 A1 three dimensional cell structures in accordance with a much larger project researching mechanism(s) of three dimensional intercellular signaling in mammary epithelial cells in response to low dose, low-LET radiation.

Phytoremediation Potential of Arabidopsis thaliana for Soil Contaminated with Chromium and Arsenic Heavy Metal Stressors. ALEXANDER PATANANAN (University of California, Los Angeles Westwood, CA 90095) JACOB PHILLIPS (Roane State Community College Harriman, TN 37748) K. PRASAD SARIPALLI (Pacific Northwest National Laboratory, Richland, WA, 99352)

With increases in heavy metal contamination due to industry and agriculture occurring worldwide, the use of plants to phytoremediate polluted environments have become a cost-effective and efficient alternative to mechanical equipment. Data acquired by two-dimensional gel electrophoresis and mass spectrometry from Arabidopsis thaliana exposed to chromium and arsenic heavy metal stressors was analyzed with PDQuestTM protein database computer software. The results provide strong arguments for site-specific activation and deactivation of proteins associated with environmental stresses. Substantial alterations in protein abundance occurred on the two-dimensional gel electrophoresis (2-DE) protein samples for arsenic at comparable standard spot positions (SSP) 120 and 6406. Proteomic data for SSP 2006 and 3006 were erratic in trend for chromium and were therefore inconclusive. In response to adding 100, 250, and 750 ppm excess heavy metal contaminants in the plant's soil, two remediation processes can occur. Either glutamylcysteinylglycine (GSH) molecules neutralize the metals or phytochelatins are produced, which transport the toxins to a vacuole within the cell where they are stored in a nontoxic form until later use. A more intense analysis of different environmental stresses on plants are predicted to reveal a global species of protein responses, suggesting that microarrays and mass spectrometry assays may lead to genetic and protein engineering of plants for rapid phytoremediation purposes.

Protein to Gene Annotation of Human Proteomics Data using Public Bioinformatics Tools and Databases. JESSICA BIAN (Yale University New Haven, CT 06520) KATRINA WATERS (Pacific Northwest National Laboratory, Richland, WA, 99352)

Mass spectroscopy-based proteomics explores cell response pathways through the epithelial growth factor receptor, which is constitutively active in malignant breast cancer cells. To correlate protein abundance with gene expression data, the specific gene that produces each protein must be identified and annotated. Incompatibility and redundancy among bioinformatics databases makes this a complex task. A workflow incorporating several bioinformatics tools and databases was developed to annotate proteins initially identified by International Protein Index (IPI) numbers with their corresponding gene symbols. On a dataset of 7694 IPI identified proteins, 7334 (95%) were successfully annotated with gene symbols using this workflow. Invalid IPI numbers (201) accounted for the majority (56%) of unsuccessful cases. Other factors that prevented successful annotation were hypothetical or predicted proteins of unknown function and IPI identified peptide fragments without assigned gene identifiers. Manual annotation methods, like the ones employed in this project, are currently the most common means by which scientists interpret experimental data. However, this is a time-consuming and inefficient process that has become too costly to continue practicing, especially with the advent of high-throughput technologies, which generate datasets of thousands of genes and proteins. Future research demands call for the development of a computer program with the ability to annotate proteins with gene identifiers using a workflow that mimics the accuracy of manual annotation methods.

Proteomic Analysis of Phanerochete Chrysosporium's Pelleted and Filamentous Fungal Morphologies. AARON SCHNEBLY (Eastern Arizona College Thatcher, AZ 85552) ELLEN PANISKO (Pacific Northwest National Laboratory, Richland, WA, 99352)

The white-rot fungi Phanerochaete chrysosporium is one of the only organisms able to completely degrade lignin, a main component of plant cell walls. This wood fungi has great potential to decompose biomass as an alternative source of energy, chemicals, and enzymes for industrial applications. Proteins produced by pelleted (yeast like) and filamentous morphologies were compared in an attempt to find differences in protein production. These different morphologies were induced by changing glucose concentrations in liquid media cultures. The cells were broken with liquid nitrogen and processed with several buffers. 2 Dimensional Gel Electrophoresis and Mass Spectrometry were used to analyze the proteins produced. The 2D Gels showed completely different protein expressions for the two growth types. Variables to study in the future include incubation time, temperature, and different chemical levels within the media. Such changes could stimulate the production of other desirable enzymes and provide valuable insight into what genes are responsible for them.

Reconstructing Genetic Regulatory Networks Using Pearson Correlation, Mutual Information and Bayesian Network Inference Algorithms. MERIDITH BLEVINS (Case Western Reserve University Cleveland, OH 44106) RONALD C. TAYLOR, PH.D. (Pacific Northwest National Laboratory, Richland, WA, 99352)

Network inference algorithms exist to understand network structure by searching for correlations across huge datasets. By applying inference algorithms to high-throughput data of RNA and protein expression levels, it is possible to establish transcriptional regulatory network structure. Such a structure or 'wiring diagram' can serve as a foundation for dynamic modeling to understand the behavior of the network over time and under different environmental conditions. This understanding will someday allow scientists to control microorganisms and lead to directed intelligent genetic engineering-an important directive to the Department of Energy's Genome to Life effort. This work will establish a baseline for future development of inference algorithms in the field of Bayesian networks and graphical models in general. Genetic regulatory network data was simulated based on a Boolean gene state model. Three techniques that use correlation in gene states were applied and compared-Pearson correlation, mutual information, and Bayesian Markov Chain Monte Carlo (MCMC) structure learning. The output of each algorithm was examined based on three common metrics-Recall, Precision and F-Measure. Results were collected for varying parameters with the goal of determining the best score cut-off to use for each method in identifying the regulatory edges. A fourth technique modified the dataset for Bayesian MCMC network inference by introducing some simulated lab experiments where genes were silenced or over-expressed. It is our conclusion that Bayesian MCMC network inference is superior to Pearson correlation and mutual information methods. The algorithm's performance improved further with the simulated blocking of genes. The future directive is to further investigate MCMC and other Bayesian network structure learning algorithms and their parameters using additional simulated topologies.

Shrub Cover and Arthropod Diversity in a Landscape Altered by Fire. JEREMY ENDSLEY (Sacramento City College Sacramento, CA 95822) ROBIN DURHAM (Pacific Northwest National Laboratory, Richland, WA, 99352)

Little is known about the relationships that exist between post-wildfire big sagebrush (Artemisia tridentata) plant communities and arthropod diversity and richness on eastern Washington's ecologically sheltered Hanford Site. Following a fire on the Hanford site in 2000, a study was conducted in the summer of 2005 which compared the diversity and richness of arthropods to shrub cover on both burned and unburned sites. This investigation was used to test the hypothesis that a positive relationship would exist between shrub cover and arthropod diversity and richness. No comparisons of understory vegetation were made. Three 200-m x 100-m biological resource management (BRMaP) plots, one unburned and two burned, were studied. Arthropods were sampled using pitfall traps in May 2005 after four trap nights. The arthropod collection was keyed to family, and to species where possible, to determine richness and diversity. Shrub cover was measured in July 2005 along each of the pitfall trap lines. Surveys found greater arthropod family richness on sites with greater shrub cover. Plant bugs (Lygaeidae) and most of the spiders were found on the unburned plot while grasshoppers and ants were more abundant on the burned plots. These differences may be the result of diverse niches made available by fire and exploitation of those niches by arthropods of differing life strategies. Suggestions for future research include a systematic and seasonal survey of arthropod abundance and diversity immediately following a fire event and in intervals thereafter to track changes.

The Effect of PAHs and PCBs on Eelgrass (Zostera marina L.) Growth. RACHEL MOFFITT (Yakima Valley Community College Yakima, WA 98903) RON THOM (Pacific Northwest National Laboratory, Richland, WA, 99352)

Despite the importance of eelgrass (Zostera marina L.) in improving water quality and as an ecosystem, little is known about how eelgrass meadows respond to indirect human impacts such as climate change and increases in nutrients, pollutants, and water temperature. The effects of light availability on the plants, including how epiphytes can reduce the amount of light available to eelgrass, is well understood. Long term monitoring of eelgrass may help us understand how indirect impacts such as pollution affect the meadows and to observe the natural dynamics of the meadow. In order to observe how the meadows can change from one year to the next, an eelgrass meadow (Site A) in Sequim Bay near the Pacific Northwest National Laboratory (PNNL) Marine Sciences Laboratory (MSL) was monitored for growth. To determine the impact of organic chemical pollutants on eelgrass, another site within the meadow was used as a control (Site B) and growth was measured for it, two experimental tanks (containing organic pollutants of PAHs (polynuclear aromatic hydrocarbon) and PCBs (polychlorinated biphenyls) and eelgrass transplanted from Site B), and also a control tank. Samples were marked and harvested at two-week intervals at low tide from June to August 2005. Growth was determined by dry weight samples of new leaf material and compared between sites. Site A was also compared to previous data from the site collected since 1991 [1]. Epiphytic mass and light attenuation were also measured for their impact on the sampling locations. Site A had a higher growth rate than Site B, but Tank 3 had the highest average growth rates, while Tank 2 had the lowest. Site B appeared to be affected by epiphyte levels, which were higher by weight than for any other sampling location. The growth in the eelgrass tanks were primarily affected by light, due to the use of different light sources, some with lower intensity than others. In general, the organic pollutants do not appear to have affected the growth in either experimental tank.

The Effects of Transmitter Size to Fish Body Weight on Transmitter Expulsion and Mortality in Rainbow Trout. SARAH STABLES (University of Virginia Charlottesville, VA 22903) RICHARD S. BROWN (Pacific Northwest National Laboratory, Richland, WA, 99352)

Acoustic telemetry is used in the Pacific Northwest for tracking salmon migrating up and down stream, including their passage through the many dams along the Columbia River. This type of telemetry on juvenile salmon is fairly new and little research has been conducted on transmitter expulsion and mortality rates in these studies. We chose to study these variables in rainbow trout (Oncorhynchus mykiss) because their body structure is similar to that of salmon and they are readily available for lab studies. We are attempting to gather information about fish mortality and tag expulsion rates for juvenile rainbow trout after the insertion of acoustic transmitters into the abdominal cavity. We salvaged 0.65 gram acoustic transmitters from prior studies and inserted them into four groups of fish. The fish were grouped into categories based on the ratio of body mass to transmitter mass. The groups were at transmitter mass percentages of 2, 6, 9, and >10, along with a control group that consisted of all 4 sizes. Fish in the control group were not implanted with a transmitter. The study will be long term, possibly lasting up to a few years. The fish were implanted with transmitters on July 21, 2005. As of August 4, 2005, a total of nineteen fish have died in the study. Tag expulsion occurred in eight of these fish, although it is unclear whether the tags were expelled before or after death. Thirteen of the nineteen mortalities (68%) occurred in the group with the smallest fish (>10%). The other six deaths occurred in the 9% and 5% groups, while the fish in the control and 2% group experienced no mortality or tag expulsion. We expect that the majority of deaths occurred in the >10% group due to the smaller abdominal cavity in these fish. Since there is less room for the transmitter, more pressure is put on the incision wound and internal organs. This pressure often resulted in tag expulsion at the incision wound or death. Previous studies on tag expulsion in salmon and rainbow trout suggest using tags that take up no more than 2% of fish body weight. However, since little research has been conducted in this field, more testing on transmitter expulsion may prove otherwise. If scientists find that salmon can hold transmitters that take up more than 2% of their body mass, tracking studies may benefit greatly. Scientists could then use smaller fish in studies and also conduct longer studies due to the ability to increase battery size.

USE OF SDS-PAGE TO DETERMINE PROTEIN VARIABILITY OF SOYBEAN CYST NEMATODE POPULATIONS IN TENNESSEE. JACULINE WILGAR (Salt Lake Community College Salt Lake City, UT 84130) STEVE GOHEEN (Pacific Northwest National Laboratory, Richland, WA, 99352)

Soybean cyst nematode (SCN) is the most serious pest to soybean crops in the U.S. Previous published research on the variability in members of the Heteroderidae (cyst nematode family) has examined potential molecular differences to identify species and to attempt to describe population variability. The primary objective is to identify protein patterns of four significantly different Tennessee SCN populations and to determine common proteins that may be involved in the attachment to or degradation of the soybean root. The first step in identification of SCN proteins was to perform sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to determine whether there are gross differences in the proteins when separated according to size. Identification of proteins will help identify biochemical differences and help determine a common genetic link. Initially more similarities than differences have been found. Future work will focus on using additional techniques that may include capillary electrophoresis, and matrix-assisted laser desorption ionization (MALDI) coupled with mass spectrometry to differentiate between the nematode cyst proteins. However, it is possible that all SCN populations are nearly identical bio-chemically and that differences need to be found in the specific organelles of the adult nematodes. Other subtle differences could be found in DNA fragments, which will also be examined in future studies.