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Friday's Sessions.

Section I-A. Biological Sciences Room 1110, Building B Robert Paul, Presiding

2:15 MICROINVERTEBRATES OF MOORES CREEK, NORTHWEST GEORGIA, IN RESPONSE TO A LOCAL SEWER SYSTEM, Hannah Campbell [*], Reinhardt College, Waleska, GA 30183. The benthic microinvertebrates of Moores Creek, Cherokee County, Northwest Georgia, were examined. Moores Creek is a small primary order stream crossing the campus of Reinhardt College. The research examined the relationship between the benthic microinvertebrates and their environments above and below the effluent point source from a sewage treatment system. Sixty-six specimens were gathered and identified. The specimens belonged to the orders of Plecoptera, Coleoptera, Diptera, Ephemeroptera, Odonata, Tricoptera, and Neuroptera. The differences in the species recovered above and below the point source were noted. The orders Plecoptera, Odonata, Ephemeroptera, Tricoptera, and Diptera dominated above the point source, while the orders of Coleoptera and Neuroptera dominated below.

[To conserve space, abstracts have been edited]

2:30 EUTROPHICATION OF MOORES CREEK, NORTHWEST GEORGIA, AS INDICATED BY ALGAE, Melissa Rottenberg [*], Reinhardt College, Waleska, GA 30183. The epiphytic algal flora of Moores Creek, Cherokee County, Northwest Georgia, was examined. Moores Creek is a small primary order stream crossing the campus of Reinhardt College. Seven sites were selected which include both riffles and pools along the stream course, above and below an effluent point source from a sewage treatment system. Differences in the composition of the epiflora above and below the point source are documented.

2:45 MONITORING AMPHIBIAN POPULATIONS BY CALLING SONGS, Traci Nichols [*], Kennesaw State University, Kennesaw, GA 30144. Amphibian populations appear to be declining world-wide but there is little quantification of this phenomenon. The North American Amphibian Monitoring Program (NAAMP) is implementing anuran calling surveys across the U.S., Mexico, and Canada in order to provide needed baseline data. Volunteers carry out calling surveys along randomly designated routes which include 10 stops where species composition and rough estimates of population density are determined by listening. The NAAMP compiles the data. Route 501 in Cherokee Co., Georgia has been monitored since 1997. A variety of species was noted, with an uneven distribution across stops and habitats. Some areas have greater population densities than others, and the number of species varies from 1 to 7. There is a need for additional routes in Georgia; currently route 502 is the only one. Efforts to establish 2 new routes in Georgia are now u nderway.

3:00 SHARED GROUP REPERTOIRES OF THE AMERICAN CROW (CORVUS BRACHYNCHOS) AND THEIR FUNCTION IN SAME GROUP RECOGNITION, Ramona Nichols [*] and Robert Paul, Kennesaw State University, Kennesaw, GA 30144. The distinctive and easily recognizable "caw" call of the American crow, Corvus brachyrhynchos, is only part of their extensive vocabulary. Vocalizations recorded in the field during a directed study performed Summer quarter 1998 from three local populations suggest that each group has its own shared group repertoire. Sonograms showed significant differences in element length, interval length, and total length in some of the call types tested. For example, the mean lengths of 4 element calls were as follows: Kennesaw = 1972 ins, Dahlonega = 1572 ins, and Alpharetta = 1497 ins. The mean lengths of juvenile calls were: Kennesaw = 1296 ins, Dahlonega = 1427 ins, and Alpharetta = 1532 ins. Playback experiments suggest that crows may use shared group repertoires for same group recognition. The home population vocali zed more frequently during an alien adult call playback and also made more flight movements toward the speaker during alien adult and alien juvenile call playbacks as compared with playbacks of their own group's calls.

3:15 A PRELIMINARY ASSESSMENT OF THE LIFE CYCLE STRATEGY OF HOPERIUS PLANATUS FALL (COLEOPTERA: DYTISCIDAE) IN CENTRAL GEORGIA, Deborah A. Mooney [*], E.H. Barman, and J.W. Johnson, Jr., Georgia College & State University, Milledgeville, GA 31061. The monotypic genus Hoperius is restricted to the southeastern United States and in Georgia has been reported only from Clarke County. Mature larvae were collected from late April to early May 1998, from temporary (polyxeric) habitats in Jasper County, Georgia. Evaluations of dytiscid life cycles have been confined largely to species or populations reproducing in cold temperate regions. Consequently, most dytiscids have been characterized as univoltine with adults overwintering to oviposit in the spring. The presence of mature larvae in the Jasper County habitats, suggesting that oviposition had taken place in the first two weeks of March, is consistent with a univoltine life cycle. However, mature larvae of Hoperius planatus were also collected in Hancock County f rom similar habitats, but these were taken in late August (1996), indicating that oviposition for that population occurred in late July. Thus, in the lower Piedmont of Georgia, Hoperius planatus employs either a bivoltine or multivoltine life cycle strategy. This project was supported in part by a Faculty Research Grant awarded by the Office of Research Services, Georgia College & State University. Aquatic Coleoptera Laboratory Contribution No. 23.

3:30 NATURAL HISTORY OF COPELATUS CAELATIPENNIS PRINCEPS YOUNG (COLEOPTERA: DYTISCIDAE) IN CENTRAL GEORGIA WITH RELIMINARY COMMENTS ON THE CHAETOTAXY OF THORACIC APPENDAGES OF ITS MATURE LARVA, J.E. Mashke [*], E.H. Barman, and J.W. Johnson, Jr., Georgia College & State University, Milledgeville, GA 31061. Larvae of Copelatus were collected (19 April -- 4 May 1998) from temporary (polyxeric) woodland and roadside habitats in Jasper County and cultured into the adult state. The presence of mature larvae in April was indicative of oviposition that would have occurred in mid-March. Collection sites were characterized by shallow water ([less than or equal to] 25 cm) over muddy, clay substrates that supported few or no macrophytes. Neither fish nor odonate larvae were collected concurrently with Copelatus larvae. Copelatus larvae declined in number and were no longer collected from these sites by the end of May. A corresponding increase in the abundance of larvae of Hoperius planatus Fall was observed and larvae of Laccophilus (sp. indet.) were numerous before the sites dried up in late May and early June. Sensillar patterns observed on coxae and trochanters of mature larvae of Copelatus corresponded closely to those predicted from evaluations of primary (ancestral) sensilla for the family Dytiscidae. However, positional and numerical differences were observed on femora, tibiae, and tarsi with femora exhibiting the most pronounced differences. This project was supported in part by a Faculty Research Grant awarded by the Office of Research Services, Georgia College & State University. Aquatic Coleoptera Laboratory Contribution No. 22.

3:45 CAN THE AMERICAN CROW, CORVUS BRACHYRHYNCHOS, SELECT HIGH FAT CONTENT FOODS? Jody L. Frost [*], Kennesaw State University, Kennesaw, GA 30144. This study was undertaken in order to determine the ability of the American crow, Corvus brachyrhynchos to select high fat-content foods. Four different kinds of food were placed on two bags in an area known for high crow activity on the Kennesaw State University campus. Observations were made on the order and the quantity of each foods consumed by the crows in question. This research conducted on the foraging behavior of two different families of crows concluded that both flocks of crows exhibited preferences for foods with a high fat content. The observed crows consumed 75% of the foods containing a high fat content versus 18% of the foods with low or no fat content. Statistical analysis indicated that both families of crows could actively or positively select foods with a high fat content. Analysis also showed that a significant difference was observed between the different levels in fat content. Although numerous experiments have been executed concerning selection, it has not been determined how these birds are able to identify fat content in foods.

4:00 IDENTIFICATION OF MUSCLE REGULATORY FACTORS IN THE RED SWAMP CRAYFISH, Laura Knight [*] and Glenn P. Briley, State University of West Georgia, Carrollton, GA 30118. The U.S. harvest of crayfish production for food will probably double within the next ten years. In addition to production numbers, an emphasis on increased size of individual crayfish has become an important consideration for U.S. crayfish producers in recent years as a result of competition from imported tail meat and demand from European markets. Molecular markers are being used to identify and determine the inheritance of desirable economic traits, including meat production, in species ranging from cows to catfish. Skeletal muscle development is directed by a family of highly conserved genes collectively known as the Muscle Regulatory Factors (MyoD, Myf-5, myogenin, MRF4). During embryonic development, the expression of these genes defines the number of muscle fibers that will be present in the adult. Genes isolated in the crayfish w ill be compared to genes identified in other species for similarities and differences in both the functional and regulatory regions. The goals of this project are: (1) to create a cosmid genomic library of the red swamp crayfish, Procambarus clarkii, (2) to clone and characterize genes involved in skeletal muscle growth of the crayfish, and (3) to identify genetic markers in the crayfish genome that can potentially be used in the selection of individuals with economically desirable traits.

4:15 ARTHROPODA FROM BROXTON ROCKS NATURE RESERVE, COFFEE COUNTY, GEORGIA, USA, F. Michael McAloon [*], Daniel V. Hagan [1] and John D. Spooner [2], Department of Biology, Georgia Southern University, Statesboro, GA 30460-8042 [1] and Department of Biology, University of South Carolina, Aiken, SC 29801 [2]. Broxton Rocks Nature Preserve (31[degrees]44'N, 82[degrees]51 'W), managed by The Nature Conservancy, consists of a coniferous, hardwood forest surrounding numerous sandstone outcrops of various sizes and topographies, and is a unique habitat in the Coastal Plain of Georgia. The Preserve contains numerous endangered and threatened plants, and has a rich assemblage of arthropods which until now were unknown. A survey of arthropods of the Preserve began August 1998 using various trapping methods including CDC and UV light traps, pitfall and malaise traps, and vegetation sweeping. Arthropods collected at 5 sites in the preserve, included these 9 insect orders (with number of families on parentheses): Coleopt era (15), Diptera (12), Hymenoptera (10), Hemiptera (9), Lepidoptera (9), Homoptera (4), Siphonaptera (2), Phasmida (1), and Mecoptera (1). Acari included Arachnida, Pseudoscorpionida, Scorpionida, Oribatei, Mesostigmata, Astigmata and Ixodidae.

4:30 ORIBATID MITES AS INTERMEDIATE HOSTS OF ANOPLOCEPHALA MANUBRIATA, CESTODE OF THE ASIAN ELEPHANT IN INDIA, F. Michael McAloon [*] [1], M.A. Haq [2], and Daniel V. Hagan [1], Department of Biology, Georgia Southern University, Statesboro, GA USA 30460-8042 [1] and Department of Zoology, Calicut University, Kerala, India [2]. A total of 602 oribatid mites (Acari: Oribatei) comprised of 23 species were collected during November 1997, from the Kodanadu Forest Range, Ernakulum District, Kerala, India. Samples of soil and detritus including the elephants' (Elephas maximas) dried palm leaf bedding were taken from around the dung piles of elephants known to be infected with Anoplocephala manubriata (Railliet) and placed in Berlese funnels. The oribatid mites were cleared with Hoyer's medium and slide mounted to determine presence of ingested cestode eggs or developing cystercercoids within the mites. These species of oribatids were found to contain at least one immature life stage of A. manubriata: Galumna flabe llifera orientalis, Scheloribates latipes, S. praeincisus, Xylobates seminudus, X. triangularis. This is the first known report of oribatids as intermediate hosts of Anoplocephala manubriata, cestode of Elephas maximus.

Section II-A. Chemistry (Analytical)

Room 1170, Building B

Jeanette Rice and David Jenkins, Presiding

1:15 POROSITY AND MATRIX COMPOSITION EFFECTS ON SOIL REMEDIATION USING SUPERCRITICAL FLUID EXTRACTION, Rebecca L. Owen [*], W. Clay Davis, Catrena Higginbotham and Jeanette K. Rice, Department of Chemistry Georgia Southern University, Statesboro, GA 30460. Since 1980, the EPA has identified 1300 priority-one sites which pose danger to plant and animal life, yet only 3% have been successfully remediated. An effective and inexpensive technique for soil clean-up is needed. Supercritical fluid extraction (SFE) is an attractive option; however, developing optimal extraction conditions is difficult because of the variability of natural soils. In this work, we present our results on the comparison of extraction efficiencies for removal of polyaromatic hydrocarbons (PAHs) from sol-gel monoliths that serve as model soils. Pressure effects on efficiency stabilize at 4000 psi for both neat and co-solvent modified [CO.sub.2]. Extraction efficiencies nearing 100% have been achieved for tetraethoxyorthosilicate (TEOS) gel s with [CH.sub.3]CN co-solvent modified [CO.sub.2] at 3000 psi and 45[degrees]C. Results for tetramethoxyorthosilicate (TMOS) gels under the same conditions yield efficiencies of less than 40%.

1:30 ENVIRONMENTAL MONITORING OF BIG CEDAR CREEK, POLK COUNTY GEORGIA: AN INTERDISCIPLINARY APPROACH, Crista Arrington [*], Paul Asanga [*] and Andrew Leavitt, Department of Chemistry, State University of West Georgia, Carrollton, GA 30118. An interdisciplinary environmental project has been initiated to determine the effects of human activities, land use, and rainfall levels on nitrate and pH variations of a small stream in the Valley and Ridge Province of northwest Georgia. Students from the areas of chemistry, biology, and geology are gathering data to be used collectively to assess the overall environmental health of the area. The chosen area of Big Cedar Creek in Polk County, Georgia provides in interesting case study of how the presence of human activities in the form of three EPA super fund cleanup sites and the municipal sewage treatment plant for the city of Cedartown, Georgia can affect a local ecosystem. Levels of important anions such as phosphate, nitrate, sulfate, along with heavy metals and vo latile organics will be monitored and reported as work in progress.

1:45 CHARACTERIZATION OF PORE STRUCTURE OF MODEL SOILS: APPLICABILITY FOR ENHANCED REMEDIATION TECHNIQUES, W. Clay Davis [*], Rebecca Owen and Jeanette K. Rice, Department of Chemistry, Georgia Southern University, Statesboro, GA 30460. A primary difficulty in widescale application of supercritical fluid extraction to soil remediation is the inherent inconsistencies in soil samples (e.g., porosity). We create model soils using sol-gels that allow the systematic study of porosity effects on remediation efficiencies. A primary difficulty in using sol-gels to study soil remediation is the continuous shrinkage of the pores over time, which results in entrapment of the solute and prevents extraction. We have determined that drying the gels with supercritical [CO.sub.2] results in a fixed internal structure. Tetramethoxyorthosilicate (TMOS) gels that were supercritically dried yielded an average pore radius of 10.48 ([+ or -]0.02) over a five week period of constant exposure to air (post drying). Time studies of t he pore size showed modest decreases (0.50%) for gels that differed in aging time by one week. Preliminary data suggests that the observed decreases in extraction efficiency with time are caused by caging of the analyte within the internal pores of the sol-gel matrix.

2:00 REACTIVITY OF METHANOL TOWARD NaCl (100), William T. Wallace [*], T. Patrick Hynes, James S. Burges, Thomas G. Drummond, Christopher L. Lane, Farooq A. Khan and Andrew J. Lea vitt, Department of Chemistry, State University of West Georgia, Carrollton, GA 30118. A temperature-programmed desorption study of methanol adsorbed onto NaCl(100) was performed. Methanol was adsorbed onto the surface held at a temperature of 100 K at a variety of coverages, then thermally desorbed into a quadrupole mass spectrometer in an ultrahigh vacuum chamber. Methanol dissociatively adsorbs onto the surface and desorbs in a second-order process at [sim]363 K for coverages corresponding to 10% of a monolayer. As the coverage is increased to a full monolayer, the temperature of desorption increases to [sim]395 K indicating a stabilization of the monolayer by the addition of a methanol adlayer on the first monolayer and increased hydrogen bonding within the monolayer. The multilayer desorption feature appears at [sim]250 K and increases to [sim]275 K with increasing methanol fluence due to stabilization of the multilayer by hydrogen bonding within the multilayer. These results suggest Volmer-Weber growth mode where the methanol monolayer is stabilized by the addition of an adlayer of methanol.

2:15 FLUORESCENCE SPECTROSCOPY AS A PROBE IN THE STUDY OF THE DISTRIBUTION OF PAHS ON CAB-O-SIL, Shelly [Reade.sup.1] [*], John T [Barbas.sup.1], Mike E. [Sigman.sup.2] and A.C. [Buchanan.sup.2], Valdosta State University, Valdosta, GA [31698.sup.1] and Oak Ridge Laboratory, Oak Ridge, TN 378312. Several substituted pyrenes have been covalently bonded to the silanol groups of cab-O-sil through alcohol side chains of varying lengths and at varying coverages. The fluorescence spectra obtained show both monomer as well as excimer emission. The ratio of monomer to excimer emission depends on the length of the side chain and the ease of its flexibility as well as on the surface coverage. Even at very low coverages excimer has been observed which indicates that these compounds do not cover the surface uniformly but rather in aggregate form.

2:30 DETERMINATION OF THE FRACTAL DIMENSION OF GEORGIA SOILS BY NITROGEN ADSORPTION, Gordon Baldwin [*] and J. David Jenkins, Georgia Southern University, Statesboro, GA 30460. The adsorption of pesticides and herbicides onto soils plays an important role in the mobility of these kinds of contaminants through the soil. An important factor in these interactions is the physical structure of the soil surface. Measurement of the fractal dimension, D, of soil particles should result in a better understanding of the relationship etween particle morphology and the mobility of organic contaminants through the soil. The fractal dimension is a quantitative measurement of the irregularity of the surface. Values of the fractal dimension, D, range from 2.0 to 3.0. The larger the fractal dimension, the more irregular is the surface of the particle. The fractal dimension is determined from nitrogen adsorption data by the Avnir-Jaroniec method.

Section II-B. Chemistry (Organic/Inorganic)

Room 1140, Building B

Richard Wallace and Vicky Bevilacqua, Presiding

1:15 SYNTHESIS AND COMPUTATIONAL STUDIES OF NOVEL SPIRO-BARBITURATES, Amanda Harris [*], Sangeetha Gomadam, Sharmistha Basu-Dutt and Glenn W. Esslinger, Dept. of Chemistry, State University of West Georgia, Carrollton, GA 30118. Barbiturates produce a wide spectrum of Central Nervous System responses. The nature of response depends on their half life which can be quite short (several minutes), longer (one to two days) or very long (four to five days). The duration of the drug's effect depends on their solubility in lipids or water. Solubility is dependent on the substituent groups present on the barbituric acid. We have synthesized several spirocyclo barbiturates where the [R.sub.1] And [R.sub.2] substituent groups were fused together and replaced by a [C.sub.4], [C.sub.5] or [C.sub.6] ring. We have used a computationally derived structure-activity relationship based on eleven commercially available barbiturates to predict the solubility and the therapeutic properties of these new compounds. Our spirocyclobut yl, -pentyl and --hexyl compounds were found to be hydrophilic and are predicted to treat anti-insomnia. Substitution of the carbonyl by a thio group made the spiro-butyl, -pentyl and --hexyl compounds lipophilic and are predicted to be used as anesthetic drugs.

1:30 SYNTHESIS OF A DIFFERENTIALLY PROTECTED D-GLUCOSE AS A PRECURSOR TO A CHIRAL 2-DEOXYSTREPTAMINE, Jill D. Buckthal [*], Joseph R. Millican, Jan M. Williams and S. Todd Deal, Georgia Southern University, Statesboro, GA 30460. The inositol 2-deoxystreptamine (2-DOS) is a central component of many aminoglycoside antibiotics, e.g. neomycin. Total syntheses of 2-DOS-containing antibiotics is hindered by the fact that 2-DOS is a meso compound and when employed in a synmthetic scheme typically yields inseparable diastereomeric mixtures. As a solution to this problem, we seek to synthesize a differentially protected, chiral 2-DOS from D-glucose. Our progress toward the synthesis of a differentially protected D-glucose precursor will be presented.

1:45 SYNTHESIS OF A CHIRAL DIENOPHILE FROM D-GLUCOSE, Joseph R. Millican [*], Jan M. Williams, Jill D. Buckthal and S. Todd Deal, Georgia Southern University, Statesboro, GA 30460. In an effort to control the stereochemical orientation of the Diels-Alder [4+2] cycloaddition reaction, we seek to prepare chiral dienophiles from carbohydrate starting materials as shown in the scheme below. We believe the position of substituents on the dienophile ring will influence the orientations of attach available to the diene. Our progress towards the synthesis of the glucose-derived dienophile will be presented.

2:00 SYNTHESIS, PURIFICATION AND ULTRAVIOLET VISIBLE SPECTRAL CHARACTERIZATION OF PYRENYL PORPHYRIN, Adegboye O. Adeyemo, Kolin Newsome [*], Olarongbe Olubajo and George N. Williams, College of Sciences and Technology, Department of Chemistry, Savannah State University, Savannah, Georgia 31404. A condensation reaction between pyrrole and 1-pyrenecarboxaldehyde, in propionic acid under reflux conditions, produced the new porphyrin. Purification was achieved by passing a chloroform solution of the crude product through an alumina column. Complete evaporation of the eluent afforded the new product in 10.7% yield. A chloroform solution of the pure porphyrin shows absorbance maxima at 434, 521, 556, 593 and 650 nm.

2:15 CHARACTERIZATION AND REACTIVITY STUDIES OF A FUNCTIONAL BIOMIMIC OF CATECHOL DIOXYGENASE, Justin Cribbs [*], Kathryn Roberts, Michael McCutchen, Robert Sprinkel and Will Lynch, Department of Chemistry, Armstrong Atlantic State University, Savannah, GA 31419. Modeling studies of the iron protein catechol dioxygenase is reported. The complex Fe(III)(T1Et4MIP)[Cl.sub.3] [where T1Et4MIP = tris(1-ethyl-4-methylimidazolyl)phosphine] has been synthesized and found to coordinate in a 1:1 stoichiometry with substituted catechols. These interactions are monitored by UV-Vis spectroscopy with [lambda][max.sub.1] in the range of 560 nm -- 380 nm and [lambda][max.sub.2] between 890.nm -- 714 nm depending on the substitutent group(s) on the catechol. The corresponding absorbances, found in the bound protein at 490 nm and 700 nm, arise from catechol [right arrow] Fe(III) charge transfer transitions. The relationships between the electronic spectra and the substituent group have been correlated to the Hammett parameter w ith [R.sup.2] = 0.93 and 0.99 for the high and low energy transitions respectively. In the presence of dioxygen, the complex has been found by GC/MS to cleave the catechols to the corresponding muconic acids. This work was supported by the American Chemical Society Petroleum Research Fund # 30550-GB3.

2:30 CORRELATION OF MOLECULAR ORBITAL CALCULATIONS TO ELECTROCHEMICAL PROPERTIES FOR Fe(II) AND Co(II) COMPLEXES, San geetha Gomadam [*], Bryan Eaves, Sharmistha Basu-Dutt and Spencer Slattery, Dept. of Chemistry, State University of West Georgia, Carrollton, GA 30118. Electronic properties play a major role in photophysical, spin equilibrium and electrochemical behavior which has widespread applications in molecular electronics, catalysis, information recording and energy conversion systems. Several series of Fe(II) and Co(II) complexes composed of mono-substituted terpyridines have been prepared in our laboratory. Electrochemical redox properties of these compounds were found to be dependent on the number and nature of electron donating capacity of the substituents. A detailed computational study on both these series was also performed to understand the properties of the compounds on a molecular level. The structures were optimized using PM3-tm quantum chemical method within the SPARTAN molecular modeling p rogram. Molecular orbital (MO) energies (HOMO and LUMO) were calculated and correlated to the Fe(III/II) and Co(III/II) redox potentials as the substituents were varied. Computational MO energies correlated linearly with electron donating/withdrawing substituent properties. (Hammett constants) and experimentally measured redox properties.

2:45 INTERACTION AND ACTIVATION OF PHENOLS AND CATECHOLS WITH DIOXYGEN AND A COPPER TRIS(IMIDAZOLYL)--PHOSPHINE COMPLEX, Kathryn [Roberts.sup.1] [*], Justin [Cribbs.sup.1], Will [Lynch.sup.1], Robert [Sprinkel.sup.1] Michael [McCutchen.sup.1], and D.M. Kurtz, [Jr..sup.2], Armstrong Atlantic State University, Savannah, GA [31419.sup.1] and University of Georgia, Athens, GA [30602.sup.2]. The ability of the complex, Cu(II)(T1Et4MIP)[Cl.sub.2](1) where T1Et4MIP = tris(1-ethyl-4-methyl-imidazol-2-yl)phosphine) to activate phenols and catechols toward coupling reactions was investigated. Complex (1) has been observed to bind phenols and catechols via UV-Vis ([lambda]max [approximate] 400 nm). In the absence of molecular oxygen no activation reaction has been observed. When (1) is reacted with an excess amount of various alkylphenols under an atmosphere of dry dioxygen, the alkylphenols were converted to the corresponding 4,4'-biphenols. The turnover numbers for the coupling reaction per copper complex have been fou nd to be 8.1 for 2,6-di-t-butylphenol, 6.5 for 3,4-di-5-butylphenol and 10.1 for 3,4-dimethylphenol, depending on substrate and reaction conditions.

3:00 NEWLY OBSERVED OPEN-CIRCUIT SILVER-CATALYZED ALUMINUM-DISSOLUTION OSCILLATING REACTION, Frank Onyemauwa [*] and Cathy Cobb, Augusta State University, Augusta, GA 30904. In the course of the investigation of the mechanism for the mercury-catalyzed aluminum-dissolution oscillating reaction, other metal-ion catalysts were tested for activity. The [Ag.sup.+] ion, in 0.2 mM concentrations in 2M nitric acid, was found to cause regular oscillations in the open-circuit potential of an 1100-alloy aluminum rod similar to the oscillations caused by [Hg.sup.2+]. In the silver-catalyzed reaction, the potential versus a platinum wire oscillates between about 0.8 V and 1.0 V over about a 20 second period. A 0.2 mM solutions of the mercuric ion in 3 M nitric acid displays oscillations between 1.1 V and 2.0 V over about a 10 second period. The similarities and differences between the mercury- and silver-catalyzed reactions served to improve our mechanistic model for these metal-catalyzed dissolution oscillation reaction s. In this work, a refined model is found in which the voltage at one extreme in the oscillations is explained by the deposition of a thin film of reduced metal catalyst and at the other by the dissolution of a metal-aluminum alloy.

3:15 FOREIGN IONS AS PROBES OF THE MERCURY-CATALYZED ALUMINUM-DISSOLUTION OSCILLATING REACTION, Ernest McGahee [*] and Cathy Cobb, Augusta State University, Augusta, GA 30904. As probes into the mercury-catalyzed aluminum-dissolution oscillating reaction, various ions were added to the reaction mixture to determine their effect on the induction time, magnitude, and frequency of the open-circuit potential oscillations of the aluminum rod. The anions affected the induction time but did not have a significant effect on the magnitude or frequency of oscillations. The trend [I.sup.-] [greater than] [SCN.sup.-] [greater than] Br is rationalized by the relative corrosivity of these ions. [Sr.sup.2+], [Zn.sup.2+], [Al.sup.3+] had no significant effect and [Ni.sup2+] increased the induction time slightly. [Pb.sup.2+], [Ag.sup.+] altered the profile of the oscillations significantly. These effects are rationalized by the activities of the various metals. In our mechanistic model for this reaction, mercury is reduced on the aluminum. Cations more active than mercury should have little effect; cations reduced by the aluminum should alter the reaction surface. Copper metal shortened the induction time and increased the frequency of the oscillations significantly. This synergistic effect is rationalized by the displacement of the mercury ion from solution by the more active copper.

3:30 MEASUREMENT OF THE SOLUTION CATALYST CONCENTRATION DURING THE COURSE OF THE MERCURY-CATALYZED ALUMINUMDISSOLUTION OSCILLATING REACTION, Charles M. [East.sup.*], Joseph A. Hauger and Cathy L. Cobb, Augusta State University, Augusta, GA 30904. In the current mechanistic model for the mercury-catalyzed aluminum-dissolution oscillating reaction, it is assumed that the mercury catalyst is deposited and then dissolved from the aluminum surface. To confirm this step in the mechanism, a study of the solution mercury ion concentration was undertaken. Because the oscillations have approximately a 0.1 sec peak width, and the time from baseline to maximum is only about 1.0 sec, it was necessary to automate the solution sampling to capture the concentration at the maximum of the peak. An apparatus, designed to withdraw the aluminum rod from the solution at various preset points in the oscillation was constructed. The apparatus used a twelve bit research grade analog to digital converter interfaced to a small compute r for voltage measurements. The aluminum rod is pulled out of solution by a lever driven by a solenoid actuator. The remaining reaction solutions were tested for mercury concentration. Test results and the apparatus design will be discussed.

3:45 OXIDATIVE CATALYSIS OF ALKANES IN SUB- AND SUPERCRITICAL CARBON DIOXIDE USING AN IRON COMPLEX, Rebecca [Owen.sup.*], W Clay Davis, Jeanette K. Rice, Will E. Lynch, Justin Cribbs and Kathryn Roberts, Georgia Southern University, Department of Chemistry, Statesboro, GA 30460 and Armstrong Atlantic State University, Department of Chemistry and Physics, Savannah, GA 31419. [Co.sub.2] has been used as the solvent under sub- and supercritical conditions for the investigation of the catalytic oxidation of alkanes. The complex Fe(III)(T1Et4MIP)[Cl.sub.3] [where T1Et4MIP is tris(1-ethyl-4-methyl-imidazolyl)phosphine] is a demonstrated catalyst for the oxidation of C-H bonds to alcohols, ketones and alkylhalides. This is accomplished in the presence of excess organic peroxide and common organic solvents under standard conditions (1 ATM., room temperature). In similar reactions run using CO2 as solvent at 2000 psi and 70[degrees]C, the catalyst is capable of oxidizing cyclohexane a total of 5.4 turnovers per metal complex in 0.5 h. This corresponds to an increase in the catalytic efficiency of 70 times compared to standard conditions. Under the same conditions, adamantane is oxidized to the 1-adamantol at 2.3 turnovers per metal complex. A solvent density profile has been recorded, determining that the catalytic function is optimized in the density range of 0.1 - 0.5 g/L with oxidative conversion percentages as high as 16% based on initial amount of alkane.

4:00 SOLUTION SPECTRAL CHARACTERIZATION OF METAL COMPLEXES OF MESO-TETRAKIS (2,4-DIMETHYL-5-SULFO-NATOPHENYL) PORPHYRIN, Adegboye O. Adeyemo, Adah Carter* and George N. Williams, College of Sciences and Technology, Department of Chemistry, Savannah State University, Savannah, Georgia 31404. Metal complexes of the above ligand were prepared by the addition of excess metal salts to the water solution of the free base porphyrin followed by gentle shaking of the reaction mixture. The ultraviolet visible spectra of these solutions taken almost immediately indicate complex formation. Water solution of the free base shows absorbance maxima at 412, 515, 551, 578 and 638 nm while the Zn(II) complex shows absorbance maxima 421, 555, 594 nm. The complete disappearance of the major peak at 515 nm of the free base porphyrin coupled with the appearance of a new peak at 555 nm for the Zn(II) complex is indicative of complex formation. Other metal complexes show similar spectral change.

Genetics Society of Georgia Special Symposium on Genetics

Room 1120, Building B

1:45 EFFECT OF DIFFERENT SUGARS ON REGENERATION OF PETUNIA EXPLANTS, Keisha Robinson*, Johnny Carter, and Seema Dhir, Agricultural Research Station, Fort Valley State University, Fort Valley, GA 31030. In the present study, the effect of three different sugars - sucrose, glucose and maltose at 30 gm/I was tested on two different explants. Node and internode segments were excised from in vitro grown petunia seedlings. A total of 6 explants were inoculated per treatment and each treatment was replicated three times. The cultures were incubated at 25 [+ or -] 2[degrees]C under 16/8 hour light/dark regime. Data was collected after 6 weeks of culture. Our results indicate that 39%, 100%, 39% and 89% node explants formed shoots, and the average number of shoots per explant varied from 2.0, 11.3, 13.0 and 13.5 on MS basal (MSB), MSB + sucrose, MSB + glucose, and MSB + maltose medium, respectively. For internodes, 8%, 28%, 39%, and 47% explants formed shoots, and the average number of shoots per explant varied from 0.0, 1.2, 2.1 and 12.6 on MSB, MSB + sucrose, MSB + glucose, and MSB + maltose medium, respectively. In conclusion, for both node and internode explants, maltose provides a better source of energy than sucrose and glucose.

Linda R. Adkison, Presiding

2:00 ANALYSIS OFARABIDOPSIS THALIANA TRANSGENIC LINES CROSSED WITH PROLIFEROUS LINES, Drew Moorman [*], Lindsey Longergan [*], Natalie Moss, and Linda L. Hensel, Mercer University, Macon, GA 31207. We have analyzed both transgenic (obtained from S. Gan of the University of Kentucky) and chemically mutagenized lines, proliferous (plf), which have inflorescence meristems that cease to undergo wild-type arrest. The resulting phenotype of both lines is a two-fold increase in fruit production. The transgenic lines analyzed were transformed through the addition of the gene, [P.sub.SAG12]IPT. The senescence associated gene, [SAG.sub.12], significantly increases expression at the onset of somatic tissue senescence, and isopentyl transferase (IPT) catalyzes the rate-limiting step in cytokinin production. Thus, the [P.sub.SAG12] promoter presumably results in the expression of the chimeric gene, and the production of cytokinin, late in senesence. We previously reported on the initial analyses of each of these lines. Si nce our last report, we have crossed the transgene into the chemically mutagenized plf lines and will report on the phenotypes of the resulting Fl and F2 plants.

2:15 DESIGN OF A GENETIC SCREEN FOR MUTANTS OF ARABIDOPSIS THALIANA THAT ARE RESISTANT TO COPPER, Nichole M. Griffith [*], Zephaniah D. Baker, and Brian W. Schwartz, Columbus State University, Columbus, GA 31907-5645. Contamination of soils by heavy metals is a growing problem. Plants that tolerate and accumulate high levels of heavy metals offer a cost-effective approach to decontamination of polluted soils. We have designed a genetic screen that will allow us to identify mutants of A. thaliana that are resistant to high concentrations of copper. Copper is an essential micrunutrient, and A. thaliana grows optimally in the presence of 2 [micro]M copper sulfate. Higher concentrations of copper sulfate induce symptoms of toxicity, including chlorosis and stunted growth of the shoot and root. We tested the effects of a wide range of copper sulfate concentrations on growth of A. thaliana and determined that 300 [micro]M copper sulfate allows normal germination and consistently produced symptoms of toxicity withou t killing the seedlings. The more normal growth of a tolerant mutant on 300 [micro]M copper sulfate should be easily recognized among wild-type seedlings. We are currently screening a large population of mutagenized plants for copper-tolerant mutants.

2:30 PRELIMINARY ANALYSES OF INSECT PROPHENOLOXIDASE cDNA CLONES, Terry Arrington [*], Erin Millage [*], Stephanie Wyles [*], and Alan F Smith, Biology Department, Mercer University, Macon, GA 31207. Phenoloxidases are ubiquitous-occurring members of a family of enzymes known as tyrosinases. Most people are aware of tyrosinase activity or deficiency by the familiar darkening of freshly peeled potatoes or the failure of pigment-producing cells to synthesize melanin in cases of albinism, respectively. In insects and other arthropods, phenoloxidases have two major functions: (1) quinone-tanning and hardening of the insect cuticle in newly molted insects, (2) wound healing and immunological responses. Prophenoloxidase, which is the inactive form of phenoloxidase, is a soluble hemolymph protein with a molecular mass ranging from 76 - 81 kDa. As a class project in Animal Physiology, it was demonstrated by SDS-PAGE and Western analysis that a polyclonal antibody to prophenoloxidase from the tobacco hornworm showed c ross reactivity to an 80-kDa protein from the hemolymph of the common house cricket (Acheta domesticus). Since then, more than ten cDNA clones have been purified from the cricket and its relative, the American migratory locust (Schistocerca americana). Preliminary analysis suggest that these are full-length clones encoding prophenoloxidases. Funding for this project was provided by Mercer University: College of Liberal Arts Faculty Research and Development Grants and the University Research Office Faculty Initiative Research Grants.

2:45 GENETIC ANALYSIS OF TWO OSMOTIC-SENSITIVE MUTANTS OF NEUROSPORA CRASSA, John Russell McGuire [*], Tawana Blocker, Sasha Dunbar, Sara Neville Bennett, and Wayne A. Krissinger, Georgia Southern University, Statesboro, GA 30460. Osmotic sensitive mutant strains of the fungus N. crassa do not grow on media with increased concentrations of NaCl. Two osmotic sensitive mutants SS-18 and SS-462 were isolated in our laboratory following UV irradiation. Previous work determined the genetic locus of SS-18 to be in either Linkage Group III or VI (LG III or LG VI) and the locus of SS-462 to be in LG VI. The mutants had several very similar characteristics, suggesting they might be alleles. However, a cross of the two mutants produced wild type progeny, ruling out allelism and furnishing information that SS-18 and SS-462 were not linked. A cross of SS-18 to os 8 indicated that SS-18 was in ILG III, and was linked to as 8 by 5.3 map units. Crosses of SS-462 confirmed its locus to be in LG VI and determined that it was linked to ad-1 by 35.9 map units and to del by 29.6 map units.

3:15 CHARACTERIZATION OF THREE MUTANTS OF NEUROSPORA CRASSA, Shemariah E.G. Love [*], Sara Neville Bennett, and Wayne A. Krissinger, Georgia Southern University, Statesboro, GA 30460. Three mutants, SS-316, SS-398, and SS-930 of Neurospora crassa were isolated in the Georgia Southern Neurospora Genetics Laboratory following UV radiation. The three mutants were originally identified as not growing as wild type on medium with 6% NaCl and thus as being osmotic sensitive. Further study has shown that of the three, only SS-316 is osmotic sensitive. The morphology of this mutant resembles that of wild type, except that conidia tend to form in clumps. Both SS-398 and SS-930 are now recognized as colonial mutants, and therefore this explained their reduced growth on medium with 6% NaCl. SS-398 is a spreading colonial which initially has restricted growth. However, with maturity the morphology of the mutant resembles that of wild type. SS-930 is a tight colonial which displays tightly restricted growth at all times. Backcrosses with wild type gave 1:1 segregation patterns for mutant and wild type traits indicating single genes under Mendelian control.

3:30 ECOLOGICAL AND EVOLUTIONARY DYNAMICS OF FLORAL POLYMORPHISM OF LINARIA CANADENSIS, Andrea S. Whatley [*] and Lorne M. Wolfe, Georgia Southern University, Statesboro, GA 30460. Linaria canadensis (Toad-flax) is a winter annual plant that exhibits two floral polymorphisms that seem to be linked. Plants make either large pale blue flowers or small dark purple flowers. The goal of this study was to quantify population morph structure and the reproductive consequences of these polymorphisms. A survey of 110 populations in Georgia and South Carolina revealed that morph frequency varied dramatically among populations. Of sampled populations, 53% had only 1 morph, 42% were about 1:1, and 5% had unequal ratios. We found that these two morphs differ in a variety of traits in addition to the size and color of the flowers. Most notable, the larger flowered morph had longer nectar spurs and as a result produced more floral nectar. We are currently investigating whether this increase in pollinator reward results in di fferential reproductive success.

3:45 GENETIC REVERTANTS OF OS-1, AN OSMOTIC MUTANT OF NEUROSPORA CRASSA, Mikako Yamauchi [*], Wayne A. Krissinger, and Sara Neville Bennett, Georgia Southern University, Statesboro, GA 30460. The osmotic-sensitive mutant of Neurospora crassa, os-1, exhibits pleiotropic characteristics of sensitivity to medium with 2% NaCl and resistance to the fungicide Vinclozolin. Wild type N. crassa exhibits resistance to 6% NaCl and sensitivity to Vinclozolin. To obtain strains which can be used to examine the os-1 locus, a marker gene, trp-1, was crossed into the os-1 strain, and os-1, trp-1 conidia were subjected to Ultraviolet irradiation to induce reverse mutation. The conidia were plated on complete medium with 6% NaCl. Forty eight colonies grew and were no longer osmotic sensitive. Their continued requirement for tryptophan supplementation assured that the isolates were not wild type contaminants. Two classes of putative revertants were identified. One class had reverted for both characteristics and now grew well on medium with 6% NaCl but not on medium with Vinclozolin. The other class had reverted for osmotic sensitivity but continued to show resistance to Vinclozolin.

4:00 PLENARY SESSION: EXPRESSION OF GREEN FLUORESCENT PROTEIN GENE IN TRANSGENIC SWEET POTATO TISSUES, Sarwan Dhir, Kent Knowles and Ajmer S. Bhagsari, Agricultral Research Station, Forth Valley State University, Fort Valley, GA 31030. The expression of the jellyfish, green fluorescent protein (GFP) gene was analyzed by transient and stable expression in sweet potato cv. Beauregard tissue by electroporation and particle bombardment. Leaf and petiole segments from in vitro raised young plantlets were used for protoplast isolation and electroporation. Embryogenic calli were also produced from leaf and petiole segments for particle bombardment experiments. The buffer solution containing one million protoplasts/ml, mixed with plasmid DNA pBIN35S-mGFP4, were electroporated at 375 V/cm. Approximately 25-30% of cultured protoplasts in KM8P culture medium regeneraged cell walls after 48 hours and of these 3% emitted bright green fluorescence when illuminated with UV-blue light. Transformed cells continuously exhibite d growth after embedding in agarose KM8P culture medium. Stable expression of GFP was observed after 4 weeks of culture in approximately 1.0% (29 microcalli out of 3,055 GFP expression cells) of the frequency of transiently expressing cells observed 2 days after electroporation. Results indicate that GFP expression can occur in various tissues and it may be a useful reporter marker to improve transformation efficiency and obtain transgenic sweet potato plants.

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Publication:Georgia Journal of Science
Geographic Code:1U5GA
Date:Mar 22, 1999
Words:6733
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