SATURDAY PAPER PRESENTATIONS.
Room AB 109
Catherine Carter, Presiding
8:00 VISITOR RESEARCH AT THE ZOO: WE STUDY PEOPLE TOO Angela M. Swilley [*] and Mollie A. Bloomsmith, Georgia Institute of Technology and TECHiab, Zoo Atlanta, Atlanta, GA 30332. With the expansion of the goals of zoological parks to include research, conservation, and education, as well as recreation, the zoo has become a facility forced to balance the interaction of many goals and users. These goals can often lead to a conflict between what is best for the animal, keeper, and visitor. This situation leads to an immediate need to evaluate all zoo users. The visitor, the desired recipient of education and recreation, is frequently understudied. Results of visitor behavior studies conducted at Zoo Atlanta will be reported. One aspect to be discussed is the effectiveness of educational materials and animal demonstrations. Visitor usage of the zoo will be also examined through hesitancy of some users to enter the Zoo Atlanta reptile house. In addition, the current age of naturalistic exhibits leads to a conflict between visitor and animal needs that should be examined. If new exhibits cause the animal to be frequently not visible, the visitor may become frustrated and not return, which leads to the loss of an opportunity to educate one more person in striving towards the goals of conservation of the animals displayed.
8:15 ANTERIOR CRANIAL MORPHOLOGY OFTHE MATURE LARVA OF THERMONECTUS BASILLARIS (HARRIS) (COLEOPTERA: DYTISCIDAE), Keith Carroll [*] and E.H. Barm an, Georgia College & State University, Milledgeville, GA 31061. Larvae of Thermonectus (tribe Acillini) are characterized as nektonic predators of zooplankton. Larvae have relatively short moderately curved mandibles with ventral teeth and closed channels between distal and proximal openings. The epipharynx is lightly to moderately sclerotized adjacent to a more heavily sclerotized trapezoidal labrum. Cranial meatuses are present on each side of the head, leading posteriorly from below the lateral loves. The meatuses turn to unite medially, forming an atrium just anterior to the mouth. The proximal pores of the mandibular channels are in contact with the anterior openings of the cranial meatuses. The injection of enzymes and the ingestion of partially digested materials are restricted to this system of mandibular channels and cranial meatuses. This project was supp orted in part by a Faculty Research Grant, Office of Research Services, GC & SU. Aquatic Coleoptera Laboratory Contribution No. 34.
8:30 SMALL VERTEBRATES OF A XERIC UPLAND WOODED HABITAT IN CENTRAL GEORGIA, Noel Williams [*] and Dennis Parmley, Georgia College & State University, Milledgeville, GA 31061. The small vertebrate population of an upland habitat in the Fall Line Sandhills of southern Baldwin County, Georgia was sampled during the summer of 2000. Drift fences equipped with pitfall traps captured 194 small vertebrates in 300 trapnights. A total of four amphibian species, five reptile species, and seven small mammal species were documented living in the habitat. Amphibians were the most abundant taxa in the sample, accounting for 57% of all vertebrates captured. Gastrophryne carolinensis was the most abundant amphibian and comprised 78% of all amphibian captures. Sceloporus undulatus was the most abundant reptile (66% of all reptile captures), and Sorex longirostirs was the most abundant small mammal (26% of all small mammal captures).
8:45 SMALL VERTEBRATES IN A LOWLAND MESIC FOREST HABITAT IN CENTRAL GEORGIA, Jane Whaley [*] and Dennis Parmley, Georgia College & State University, Milledgeville, GA 31061. Small terrestrial vertebrates were inventoried in a central Georgia (Baldwin Co.) mesic deciduous bottom woodlot using drift fences and pitfall traps between May and October, 2000. In 330 trapnights, 305 small vertebrated were captured to include nine species of amphibians, nine reptile species, and eight mammal species. Rana utricularia was the most abundant amphibian and comprised 41% of all amphibian captures. Juveniles accounted for 92% of all anuran captures. Eumeces fasciatus was the most abundant reptile (22% of all reptile captures), but was closely followed by Storeria dekayi (20% of all reptile captures). Pitemys pinetorum was the most abundant small mammal (23% of all mammal captures), followed by Reithrodontomys humulis (20% of all mammal captures).
9:00 BLENDING PSYCHOLOGY AND BIOLOGY: SCIENCE AS AN EVALUATION TOOL IN ZOOS, Christopher Kuhar [*] and Terry Maple, Georgia Institute of Technology, and TECHlab, Zoo Atlanta, Atlanta, GA 30332. As zoos continue to evolve, there is an increase in external pressures to maintain the highest standards in animal care, education, entertainment, and conservation. As a result, there is a need to enact cutting edge solutions to problems and to evaluate and quantify all decisions that are made. Zoo Atlanta, and many zoos around the nation, are more heavily relying on biological and psychological principles to accomplish these goals. Animal management issues, such as training, enrichment, reproduction, and psychological well being are being assessed using both psychological and biological methodology. Additionally, non-animal issues, such as visitor behavior and post-occupancy evaluation of exhibits, are also addressed. By combining the techniques used in these historically separate disciplines, modern zoos are able to assess all aspects of their operations to improve their decision-making abilities.
9:15 THE EFFECTS OF A VARIABLE FEEDING SCHEDULE ON MALAYAN TAPIRS (TAPIRUS INDICUS), Michael T Allen [*] and Terry L. Maple, Georgia Institute of Technology and TECHlab, Zoo Atlanta, Atlanta, GA 30315. Tapirs are unique mammals from the rain forests of South East Asia, Central, and South America. Little information is currently available on enrichment programs for many captive ungulates. This study was designed to determine how Malayan tapirs (Tapirus indicus) housed at the Woodland Park Zoo in Seattle, Washington respond to a varied morning feeding schedule. We expected to see an increase in active behaviors such as foraging and a decrease in inactive behaviors such as resting in response to the manipulation. The observations took place five days a week during 100-minute sessions for a four-week period in July and August of 1998. Data were recorded using focal animal sampling with instantaneous recording every twenty seconds. Twenty-eight hours and 20 minutes of data were collected. The tapirs' active behavi ors increased, including a significant increase in walking for the male. These preliminary results show that enrichment is beneficial to the well being of captive tapirs and that more and varied studies need to be done on these remarkable animals.
9:30 EFFECTIVENESS OF A RETREAT SPACE IN MODERATING UNDESIRABLE BEHAVIOR, Ursula Anderson [*], Marie Beene and Mollie Bloomsmith, Georgia Institute of Technology, TECHlab, Zoo Atlanta, Atlanta, GA 30332 and Bucknell University, Lewisburg, PA 17837. This study focused on the relationship between undesirable animal behavior in a petting zoo setting and spatial design. Measures of aggressive and escaping behavior, and the avoidance of humans are discussed as undesirable behavior. The spatial feature of the petting zoo, a retreat area for the animals, was manipulated with three levels: no-retreat space, semi-retreat space, and full-retreat space. The subjects of this study were five African pygmy goats (Capra hircus) and two Romanov sheep (Ovis aries). Approximately 27 hours of behavioral data, collected using a focal sampling technique, were analyzed. The findings suggest that the sheeps' behavior was beneficially moderated by the full-retreat design -- the mean frequency of leave behavioral acts was the lowest when the full-retreat was available. The goats essentially did not utilize the retreat area. This study provides information that may improve human-animal interactions and may increase animal well-being through management techniques.
9:45 PHOTOPERIODIC EFFECTS ON CALLING BEHAVIOR AND ACTIVITY IN THE LESSER CORNSTALK BORER (LEPIDOPTERA: PYRALIDAE), Tiffany [Hodges.sup.1], Daniel V. [Hagan.sup.1] and Robert E. [Lynch.sup.2], [Georgia.sup.1] Southern University, Statesboro, GA 30460 and [USDA-ARS.sup.2], Crop Protection and Management Research Unit, Tifton, GA 31793. Effects of photoperiod on frequency of calling behavior and activity in lesser cornstalk borers, Elasmopalpus lignosellus were investigated in a laboratory setting. Control virgin moth females were kept in (9L: 15D) and virgin moth females were maintained in either a continuous dark or continuous light environment. Behaviors were recorded continuously for 10 minutes with a 5 minute break for each hour of observation per treatment for 4 days. Frequency of calling and other specific behaviors were recorded. Results indicate that moths in continuous light (24L) had the highest calling behavior, while moths kept in an environment of continuous darkness (24D) had no calling. Moths maintained in 9L:15D showed the most activity, while moths in 24D darkness displayed the least activity.
10:00 Business Meeting
10:30 FERAL HORSE IMPACTS ON THE SALTMARSH OF CUMBERLAND ISLAND, Peter Dolan [*] and Lissa Leege, Georgia Southern University, Statesboro, GA 30460. Cumberland Island National Seashore (CINS) is home to approximately 250 feral horses that graze preferentially in the saltmarsh. During Summer 2000, the entire saltmarsh of CINS was surveyed to determine the extent of horse impact on vegetation. The area accessible to horses was divided into high marsh (closest to the forest) and low marsh, and species composition, grazed and ungrazed plant heights and percent cover of vegetation in 196 plots (1x2m) was recorded. Horses preferred saltmarsh cordgrass, Spartina alterniflora, over all other saltmarsh species. Grazing occurred in 59% of low plots and 73% of high plots. Grazed S. alterniflora was 1/6 the height of ungrazed S. alterniflora in high marsh ([X.sup.2]=17.4, df=1, p[less than]0.001). Total percent cover of grazed plots differed significantly only in the low marsh ([X.sup.2]=17 .9, DF=1, P[less than]0.001). Removal of S. alterniflora from the saltmarsh could negatively impact CINS because it traps sediment, reduces storm damage and provides habitat and food for many organisms. [*]
10:45 THE USE OF AN INDEX OF BIOTIC INTEGRITY AND HABITAT ASSESSMENT TO EVALUATE THE ECOLOGICAL HEALTH OF STREAMS IN CARROLL COUNTY, GEORGIA, Ashlie Blinn [*] and Christopher Talit, University of West Georgia, Carrollton, GA 30118. Carroll County forms the western boundary of metropolitan Atlanta. The waters in the county flow either into the Tallapoosa/Coosa or the Chattahoochee/Apalachiocola River Basins. In light of ever increasing demand for water due to the urbanization of this region, current drought conditions and on going water negotiations by the tristate region, it is imperative that the biological diversity and ecological health of these streams be assessed before any further degradation can occur. Whooping Creek and Snake Creek, tributaries of the Chattahoochee River are targeted for reservoir construction. Buck Creek, a tributary of the Little Tallapoosa River is currently the recipient of wastewater treatment and emergency water withdrawal. All three creeks were sampled during July/August 2000 and again during October/November 2000 using standard electrofishing techniques. Biodiversity, fish distributions, index of biotic integrity scores and an overall assessment for these three systems will be presented.
11:00 BITING MIDGES (DIPTERA: CERATOPOGONIDAE) FROM FOREST HABITATS IN NORWAY, Daniel V. [Hagan.sup.1], Ryszard [Szadziewski.sup.2], Karl H. [Thunes.sup.3] and John [Skartveit.sup.4], [Georgia.sup.1] Southern University, Statesboro, GA, [University.sup.2] of Gda'nsk, Gdynia, Poland, [Norwegian.sup.3] Forest Research Institute, Fana, Norway and [Bergen.sup.4], Norway. The Norwegian Forest Research Institute conducted a study to investigate biodiversity in Norwegian forests. Arthropod fauna were collected by pyrethroid sampling in May, June and July 1998-99 at two sites: a pine dominated boreal forest in eastern Norway (Sigdal, Buskerud) and a coastal pine forest in western Norway (Kvam, Hordaland). Among Diptera, Ceratopogonidae were most abundant. A total of 56 species in 11 genera comprised the 3,879 ceratopogonids collected. The majority were predaceous genera of midges. Genera included: Brachypogon (60.1%), Forcipomyia (14.1%), Culicoides (12.1%), Dasyhelea (8.7%), Ceratopogon (2.0%), Bezzia (1.2%) and Alluaudomyia, Schizohelea, Serromyia, Palpomyia, and Atrichopogon (each [less than]1%). Reported from Norway for the first time were 44 species including: Culicoides alatavicus and Bezzia rhynchostylata. Dasyhelea ledi recorded for the first time in Europe.
11:15 NATURAL RECOVERY AND ASEXUAL REPRODUCTION IN ELLIOTTIA RACEMOSA MUHL. EX ELLIOTT, Donald J. Drapalik, Georgia Southern University, Statesboro, GA 30460. Elliottia racemosa has tremendous ability to regenerate stem tissue and reproduce asexually via roots. January 1979, a large (400+ plants) Candler County, GA E. racemosa population was accidentally damaged during timbering. December 1981, this population was burned, and again in summer 1995 this population was damaged during timbering. Despite these disturbances, this population is vigorous. Furthermore, even though this population flowers prolifically, it is sexually sterile since mature fruits and seeds have never been observed. From January 1979 to date studies and/or observations have been conducted at this site. Almost all mechanically and fire injured Elliottia stems produced new adventitious stem shoots. In the first growing season new adventitious shoots ranged from 1 to 1860 mm in length with 1 m growth not uncommon. In later growing seasons ne w shoots flowered. Some fire damaged plants produced abnormal flowers and small, immature fruits. When injured Elliottia produces adventitious aerial stem shoots and thus new clonal plants.
11:30 VEGETATIONAL SUCCESSION IN BAHAMIAN SINKHOLES, Melanie L. [DeVore.sup.1] and Deborah [Freile.sup.2], [Georgia.sup.1] College & State University, Milledgeville, GA 31061 and [Berry.sup.2] College, Rome, GA. A large number of sinkholes are present on the north end of San Salvador. During July 2000, we initiated studies to investigate vegetation replacement of wetland plant assemblages in sinkholes. Four communities were selected representing different stages of succession. Transect sampling was employed to determine species composition in each sinkhole. Based on our results. we noted that classic hydrarch succession occurs in sinkhole communities. Early successional stages are dominated by Eupatorium sp., Paspalum laxum, and Eleocharis (emergent vegetation) surrounded by Phyla nodifolora and P. stoechadifolia. As organic matter accumulates in sinkholes, Phyla stoechadifolia will completely replace other plant species. The present study documents autogenic succession in sinkhole communities on San Salvador. Continued samp ling of sinkhole communities on the island will provide data necessary for documenting allogenic successional changes driven by rainfall. The influence of the width to depth ratio of sinkholes in community succession will also be evaluated.
11:45 ENUMERATION AND CHARACTERIZATION OF TERMITE GUT MICROBIOTA, William A. Said, Laura K. Altom, Landon C. Coleman, Urvashi Rai, Jason Teal and Nick German, Brewton-Parker College, Mount Vernon, GA 30445. One of the most interesting examples of symbiosis is the nutritional association between termites and their gut microbiota. Light microscopy was used to enumerate and examine the in situ diversity of protozoa in the hind gut of the lower termite, Reticulitermes flavipes. Trichonympha, Holomastigotes, and Sterblomastix (Class: Karyomastigea; Subphylum: Zoomastigophora) were the most abundant. The three genera likely represent some of the microbial components required for termite viability. Protozoa population ranged between 40,333 and 90,138 protozoa/termite gut. Bacterial population in termite guts ranged between 1.9 x [10.sup.3] and 2.7 x [10.sup.8] CFU/termite gut using the Standard Plate Technique. Generation time "Tg" values ranged between 1.03 and 1.89 hr.
DISCRIMINATION LEARNING IN THE COMMON SNAPPING TURTLE, CHEELYDRA SERPENTINA, Heidi L. Walker [*], Jennica E.N. Schenck, Barry K. Rhoades and James D. Rowan, Wesleyan College, Macon, GA 31210. An experimental chamber and protocol were developed to study discrimination learning with a head-poke response in the common snapping turtle. Two 10 cm diameter cylindrical head-poke receptacles were mounted perpendicular to a Plexiglas partition, which in turn was mounted at 30[degrees] to the vertical in a 30 gallon aquarium. The head-poke openings were centered 14 cm apart and 5 cm below the water level. Head-poke behavior was shaped by illuminating the interior of one receptacle via a miniature white light, delivering a single food pellet into that tube, and waiting for a feeding response in that tube. Within 20 trials a head-poke into either of the two receptacles was reliably occasioned by the onset of the light alone ([S.sub.D]) in that tube, with subsequent food delivery serving as a positive reinforcer ([S.sup.R ]) to maintain this behavior. This study provides a methodological foundation for studying the biological substrates of pattern learning in the snapping turtle.
COMPARISON OF ALDOSE REDUCTASE ACTIVITY IN WILD-TYPE AND MUTANT DROSOPHILA MELANOGASTER, Jamila Belgrave [*], Marcia Price [*], Denise Saunders and Jann P Prim us, Spelman College, Atlanta, GA 30314. In recent years, biochemists studying the metabolism of a wide variety of organisms (including humans) have focused their interest on a class of monomeric NADPH-dependent carbonyl reductases that are thought to be involved in the biosynthesis of tetrahydrobiopterin and the development of diabetic complications such as blindness. Previous studies in our laboratory have established the existence of aldose reductase in the fruit fly, Drosophila melanogaster, a model organism that lends itself to genetic, as well as biochemical study. The present study centers on comparing the enzymatic activity of aldose reductase in wildtype Drosophila to mutants with known alterations in the location of the aldose reductase gene (chromosome 3; locus 84E5-84E6). Spectrophotometric assays will be used to test crude protein extracts prepared from a wild-type Oregon-I? and mutants 1171, 1810, 1968, and P272 from the Bloomington Drosophila stock collection. Mutants 1171 and 1810 have breakpoints near the gene region that codes for aldose reductase. Mutants P272 and 1968 have respective]y an insertion and a translocation near the aldose reductase region. Studies of aldose reductase activity in genetically altered flies will help clarify the role of aldose reductase in the tetrahydrobiopterin biosynthetic pathway.
SEROLOGICAL EVALUATION OF COSTA RICAN TABANID FLY SPIROPLASMA BACTERIA, Kimberly M. Stewart [*] and Frank E. French, Georgia Southern University, Statesboro, GA 30460. In order to make evaluations of the phylogeny, biogeography, ecology, host distribution, and pathogenicity of Spiroplasma bacteria, they have to be identified and classified. They are identified through a series of serological tests that normally consists of screening, one-way deformation tests, cloning, antisera production, and reciprocal deformation tests. Serological tests on the spiroplasmas are followed by molecular tests. The preliminary serological screening was performed on 58 spiroplasma cultures isolated from Costa Rican tabanids. The detailed, necessary serological evaluations thus far have placed the 12 cultures in Group VIII and two of the cultures appear to be new species. The molecular analysis of the 16S-23S rRNA gene for the two cultures is in progress. The results of this study could become the basis for a phylogenetic analysi s of the spiroplasma flora of the United States (Nearctic) and Costa Rica (Neotropical), perhaps global.
LIFE HISTORY STRATEGIES (r VERSUS K-SELECTION) AMONG MOTHS IN DIFFERENTLY DISTURBED HABITATS, Stephanie Howard [*], Shannon Hux [*] and Paula Jackson, Kennesaw State University, Kennesaw, GA 30144. We applied the concept of r versus K-selection to moth species living in two forested habitats with different levels of disturbance. Theory indicates that a higher proportion of r-selected individuals should be observed in more disturbed areas. Because size is one of the most apparent components of the life history of an organism, we will use size (dry weight) as an indirect measure of life history strategy. We hypothesize that, on average, the more disturbed habitat will have a higher proportion of small moths (more r-selected species). To test this idea we will choose two sites with different levels of disturbance and sample moths over a period of a year, by attracting them using a UV light and white screens. After collection we will photography, identify, dry and weigh all moths sample. We will also record moth individual size, wingspan, color, and aspect diversity. An additional objective of this study is to develop a protocol for effectively collecting moths indigenous to Cobb County, GA and to contribute our findings to the Northern Wildlife Research Center database.
CELL-CELL INTERACTIONS IN IMMUNITY AGAINST HUMAN RESPIRATORY SYNCYTIAL VIRUS, La Toya J. [Perry.sup.1] [*], Tiffany [Walker.sup.2] Francis [Eko.sup.2], Joseph [Igietsema.sup.2] and Godwin [Ananaba.sup.2], [Spelman.sup.1] College and [Morehouse.sup.2] School of Medicine, Atlanta, GA 30314. Respiratory Syncytial Virus (RSV) is the major cause of severe bronchiolitis pneumonia in infants and young children. RSV is contacted by inhalation of contaminated secretions. Immunofluorescence of nasal secretions provides evidence that ciliated epithelial and immune cells contain RSV antigens and therefore are sites for virus replication. Since RSV disease is most severe in infants who still have maternal antibodies, the role of the immune system in protection against RSV infection and reinfection is not clear. Further work is needed to determine the role of cell-mediated immunity in the protection against RSV infection. In this study we examined the role of cell-cell interactions in immunity against RSV. Antibody against ICAM-1 and/or LFA1 was used to inh ibit the interactions between the T lymphocytes and epithelial cells. This resulted in a decrease in the level of IFN-[gamma] produced. The results suggest that epithelial cell-immune cell interactions influence the types of cytokines produced, which affects the host's immune response to RSV. Better understanding of RSV biology and immunity will benefit our goal of producing effective RSV vaccine(s). Supported by the MIE Program, Spelman College.
KINETICS OF CATALASE OF CERTAIN HERBS WITH SPECIAL REFERENCE TO THE EFFECT OF SHORT TERM HEAT AND COLD SHOCKS ON CATALASE REACTION, William A. Said, Landon C. Coleman, Jason Teal, Nick German, Jared L. Brown and Urvashi Rai, Brewton-Parker College, Mount Vernon, GA 30445. Kinetic characterization of catalase from certain herbs was determined by linear regression of the double reciprocal, (Lineweaver-Burk) plot for substrate concentration between 0.11 and 0.88 M. Significant correlation coefficient values of [greater than]0.960, (P [less than] 0.01) were obtained. The kinetic parameters calculated correspond to Michaelis-Menten constant, ([K.sub.m]) values of 0.796, 0.445, 0.361, 0.258, and 0.097 M, for Arugula, Mint, Basil, Cilantro and Dill, respectively. Maximal velocity, ([V.sub.max]) values ranged between 1.395 for Cilantro and 3.245 [[micro]mol.sec.sup.-1] for Dill. Catalase activity of Tarragon was suppressed by a cold shock of -12[+ or -]2[degrees]C for 15 minutes reducing the velocity of the reaction between 43.6 and 64.4%.
INFLUENCE OF PLANT GROWTH REGULATOR LEVELS AND NITROGEN CONTENT ON CALLUS INDUCTION FROM SPARTINA ALTERNIFLORA EXPLANTS, W.H. Palefsky, A.G. Harkins [*], F.M. Minix, A.Y Alexander and C.I. Franklin, Department of Biology, Savannah State University, P.O. Box 20600, Savannah, GA 31410. In saltmarshes of southeastern United States, smooth cordgrass (Spartina alterniflora) is a dominant plant species, and it can account for up to 90% of biomass production. Transgenic technology is being developed to genetically engineer S. alterniflora for use as a biosensor for heavy metal contamination in saltmarshes. An efficient regeneration system is needed for developing the transgenic technology. Influence of various auxin/cytokinin concentrations ([2-20.sup.M]) and modifications of nitrogen content on the induction of regenerable callus from young shoot and leaf explants was tested. High ammonium content or proline supplement in the culture medium caused necrosis of both explant types. However, young shoot explants cultur ed on medium containing high cytokinin levels lacking ammonium showed typical callus induction patterns. Results from this study indicate that lack of ammonium and high cytokinin levels promote callus induction from young shoot explants of S. alterniflora.
SURFACE STERILIZATION OF SPARTINA ALTERNIFLORA SEEDS USING CHLORINE FUMES - A TIME COURSE STUDY, T.D. Palmer [*], A.G. Harkins, D.E. McDowell, K.S. Thornton-Poythrusand and C.I. Franklin, Department of Biology, Savannah State University, Savannah, GA 31410. Axenic lines of smooth cordgrass (Spartina alterniflora), a dominant plant species in salt marshes of southeastern United States are being developed from surface-sterilized seeds to study plant-microbe interactions related to nutrient recycling and heavy metal contamination in the saltmarsh ecosystem. In this report, results from experiments to investigate the effect of exposure to chlorine fumes on surface sterilization of S. alterniflora seeds are presented. Seeds were exposed to chlorine fumes for 10-90 minutes (at 5-10 minute intervals) and subsequently germinated on sterile nutrient medium. Exposure to chlorine fumes for a minimum of 45 minutes yielded completely surface-sterilized seeds. At lower exposures (10-40 minutes), up to 60% microbial contami nation was observed. Exposure of seeds to chlorine fumes for more than 45 minutes drastically reduced seed viability. These results indicate that S. alterniflora seeds can be fully surface-sterilized by exposing them to chlorine fumes for 45 minutes.
FRUIT REMOVAL RATES OF FOUR SPECIES OF BIRD DISPERSED PLANTS IN GEORGIA, Theresa Tholkes [*] and James B. Ferrari, Wesleyan College, Macon, GA 31210. Fruit ripening times and removal rates were monitored for flowering dogwood (Cornus florida), southern magnolia (Magnolia grandiflora), pokeweed (Phytolacca americana), and blackgum (Nyssa sylvatica) from September through November, 2000 in Middle Georgia. Two blackgum trees and five plants each of magnolia, dogwood, and pokeweed were monitored weekly for eleven weeks. All species were ripe at the start of the study and finished by October 28 for pokeweed, November 5 for magnolia and blackgum, and November 19 for dogwood. Results were compared to fruit nutritional content and bird abundance as determined by weekly censuses.
ACTIVITY LEVELS OVER FEEDING PERIODS BY CAPTIVE FLORIDA MANATEES, Jenny Young [*] and Bruce Schulte, Department of Biology, Georgia Southern University, Statesboro, GA 30460. Thirty-two manatees at seven facilities in Florida were used to investigate behavior and differences is sex, age, and length in captivity. Scans of the major behavior exhibited were taken once a minute for 180 minutes over three continuous days. Data based on ANOVAS indicated that there was no significant influence on the behavior of manatees based on the different facilities and sexes. The length of time that a manatee has spent in captivity did not significantly influence most behaviors. This information indicates that time spent in captivity by an individual manatee may not be the only factor determining its release back into the wild and overall releasing captive manatees is the goal of facilities that house them for rehabilitation.
IMPACTS OF FOREST MANAGEMENT ACTIVITIES ON REPTILES AND AMPHIBIANS IN THE PIEDMONT NATIONAL WILDLIFE REFUGE, Clinton E. Miller [*], Megan A. Parker and Michael K. Moore, Mercer University, Macon, GA 31207. We have initiated long-term population studies of herpetofaunal species that occur in riparian woodlands and adjacent pine uplands in the Piedmont national Wildlife Refuge. Trap arrays have been established within four 1000-acre refuge compartments that vary in their history of forest management practices (i.e., frequency and timing of burning and mechanical thinning). Each compartment contains 15 drift fence-pit fall-funnel trap arrays (PFA's), comprising a total of 60 pitfalls and 30 funnel traps per compartment. Early results (derived from late spring, summer and fall of 2000) show distinct weather-induced and seasonal patterns of activity among most species captured. In addition, presence and abundance of several species are positively correlated with a particular compartment treatment. Species lists an d patterns of relative abundance are discussed in the context of evaluating forest management practices common in southern Piedmont forests.
Section II: Chemistry
Room AB 101
Thomas Manning, Presiding
8:15 DEVELOPMENT OF A LASER LABORATORY FOR UNDERGRADUATE EXPERIMENTS, M. Elizabeth Derrick and Frank Flaherty, Valdosta State University, Valdosta, GA 31698. We have acquired a [N.sup.2] pumped dye laser, a monochromator, a photodetection system, and a gated integrator through an NSF-CCLI grant to equip a chemistry/physics laser laboratory. Lab View software is being used to control the instruments. The equipment is currently housed in an experimental physics laboratory, but will eventually be moved to a special laboratory in the new chemistry/biology building. During this academic year Dr. Derrick, a physical chemist, Dr. Flaherty, a physicist, and two students, a chemistry student and a physics student, have been working together to set up the equipment. We will discuss our experiences with the development of this interdisciplinary laboratory. We will also discuss our progress in developing experiments for use in several of our undergraduate physics and chemistry courses. Our goal is to provide students the opportunity to investigate concepts involving the electronic structure of matter and lasers themselves, which heretofore could only be addressed in lectures. The laser laboratory will also be available for undergraduate research projects. Projects jointly mentored by faculty from more than one disciplinary area will be encouraged.
8:30 MOLECULAR MODELING IN ORGANIC CHEMISTRY, John Barbas and James Baxter, Valdosta State University, Valdosta, GA 31698. We have been using molecular modeling in organic chemistry for the last three years with great success. Students have been very enthusiastic about predicting the properties of simple molecules, predicting the stabilities and properties of unstable molecules and better understanding chemical reactions and stereochemistry. They have been using computational techniques to obtain property maps showing graphical distribution of electron densities, molecular size and shape, distribution and delocalization of charge, and likely sites of nucleophilic or electrophilic attack. They have been using spin density calculations in free radicals to show hyperconjugation and resonance phenomena. They have been using frontier orbitals for a better understanding of symmetry allowed reactions and to make predictions of the likely stereochemistry of products. The culmination of these computational techniques has been the visualization of the molecular motions taking place at the transition state of several actions.
8:45 KINETICS ON SURFACES USING FREE-RADICAL CLOCKS, John [Barbas.sup.1], Mike E. [Sigman.sup.2], Reza [Dabestani.sup.2] and A.C. [Buchannan.sup.2], [Valdosta.sup.1] State University, Valdosta, GA 31698 and [Oak.sup.2] ridge National Laboratory, Oak Ridge, TN 37831. The rates of radical-molecule reactions can be approximated by using competing unimolecular reactions such as free radical rearrangements as timing devices. One such free radical clock is (p-hydroxyphenyl)cyclopropylmethyl radical. Synthesis of its deuterated precursor will be discussed. Kinetic studies were done by attaching the above compound along with p-hydroxybenzophenone and a large excess of p-hydroxybiphenylmethane on activated Cab-O-Sil. Samples were evacuated, sealed and the benzophenone carbonyl irradiated with UV light. This triggers a cascade of free radical reactions leading to the ring opening of the cyclopropyl moiety in competition with hydrogen abstraction. Careful product analysis and the rate of the ring opening reaction were used to approximate the rate of the competing hydrogen abstraction.
9:00 ANIMPROVED AND EXPANDED WATERS-OF-HYDRATION LAB, Andrea W. Wallace, Coastal Georgia Community College, Brunswick, GA 31520. Finding the empirical formula of a hydrate is a standard experiment utilized in the general chemistry laboratory. In this procedure, a porcelain crucible is used to heat a hydrate that is to be converted into an anhydrate. Upon finding the mole ratio of water to anhydrate, the students are able to determine the empirical formula of the hydrate. This is an excellent laboratory for teaching empirical formulas and stoichiometry; its only drawback is the use of the porcelain crucible. These crucibles tend to break easily and require at least five to ten minutes to cool to room temperature. In the improved version of this laboratory, an inexpensive, non-breakable, reusable, and quick-cooling quartz fiber crucible is used. The laboratory is also expanded to include a second part in which a chemical mixture of the hydrate and anhydrate is analyzed and the weight percent of the hydrate in the mixture is determined.
9:15 INFRARED SPECTROSCOPY STUDIES OF SUWANNEE RIVER HUMIC ACID, Amy Feldman [*], Stacy Strickland and Thomas Manning, Department of Chemistry, Valdosta State University, Valdosta, GA 31698. Fourier Transform-Infrared Spectroscopy is used to categorize 26 humic samples collected along the Suwanee River. Humic acid from Fargo, Georgia is often used as the international standard for the product of plant and animal decay. Our group collected samples from the Okeefenokee Swamp to the Gulf of Mexico. Changes in the spectra over the course of the river will be reported.
Room SB 113
SYNTHESIS OF A TEMPLATE FRO LIGAN ATTACHMENT, Amanda Stewart [*] and Patricia Bishop, Georgia Southern University, Statesboro, GA 304608064. The synthesis of a template molecule will be described. Also discussed will be future applications of this template for ligand attachment and for the selective binding of organic molecules.
Section III: Earth and Atmospheric Sciences
Room SB 261
Md. Khalequzzaman, Presiding
8:15 METEOROLOGICAL CONDITIONS OF EXTREME HEAT INDEX EVENTS OVER THE UNITED STATES, Jong-Nam Choi [*], Vernon Meetemeyer and Thomas L. Mote, University of Georgia, Athens, GA 30605. The heat index is an "apparent temperature" which results from the combination of air temperature and humidity. Two regions in the United States consistently have the highest index values; a region in the southwest centered on Arizona and a south central region centered on Arkansas and Oklahoma. This study investigates the synoptic atmospheric patterns and the conditions near the surface which cause extreme heat index events in these two regions. Preliminary results show that extreme heat index events in the south western United States are caused by upper-level ridges that are anomalously northward displaced and subsequent adiabatic heating processes. In the south central United States, upper-level high pressure is usually present, but strong warm air advection and transport of humidity from the Gulf of Mexico are responsible for extraordinary events. Local surface conditions, such as high soil moisture, can be important in both regions. Case studies of extreme events in 1971, 1974, 1980, and 1990 are used to demonstrate the details of the meteorology responsible for extreme events.
8:30 IMPLICATIONS OF RECENT EXTREME TEMPERATURE ON DROUGHT SUSTENANCE, IN SOUTH GEORGIA, Austine O. Nnaji, Reid Jackson, Sally Jones and Brian Peterson, Valdosta State University, Valdosta, GA 31698. The association between time series of historic mean annual temperature and precipitation was examined to determine if persistent drought condition in South Georgia is forced by global warming. The study utilized over 100 years of data from selected climate stations in the sub-region, to produce coupled series plots, analysis of which revealed 25 droughts. Simulation of the fluctuation yielded suggest that global warming may have exacerbated drought condition in South Georgia. Particularly, the result showed similarity in fluctuation between extreme drought and intense warming of last decade (1997-1999). This is attributed to above normal temperature which sped up evapotranspiration and disrupted precipitation. The study concluded that South Georgia is a candidate for long-term Saharan condition if projected warm ing trend persists. South Georgia like most parts of the state experienced drought conditions in recent times which dynamically intensified from moderate to extreme in the last three years (NOAA 2000). Persistence of the drought has been attributed to climatological factors which include shifts in pressure Systems, presence of La Nina and absence of moisture bearing maritime wind from the Atlantic and Gulf of Mexico.
8:45 WEST GEORGIA WATERSHED ASSESSMENT: METHODS INVOLVED IN SAMPLE STATION SELECTION, Teddy D. Martin [*] and Curtis L. Hollabaugh, Geosciences, State University of West Georgia, Carrollton, GA 30118. Watershed assessments include a set of sample stations located at critical positions on streams/rivers. Well-developed criteria such as Georgia EPD 305(b) Report, point and non-point loading sources, areas of rapid growth, and location of sufface drinking water intakes were used in locating sample stations for the West Georgia Watershed Assessment of Heard and Carroll Counties. For this watershed assessment it was determined that 70 sample stations were needed. The monitoring plan includes 6 wet and 6 dry sample events for each sample station. To provide weekly monitoring additional samples will be collected at 23 of the sample stations so that they will be monitored weekly for one year. Water quality parameters measured will be temperature, DO, [sim]H turbidity, conductivity, TSS, hardness, Cd, Cu, Pb, Zn, nit rogen (ammonia, nitrite-nitrate, TKN), P, fecal coliform, BOD and COD. A large number of sample stations combined with frequent data collection for one year will enable determination of regional and seasonal water quality parameters.
9:00 WATER QUALITY CHANGES IN THE LITTLE YALLAPOOSA RIVER ASSOCIATED WITH THE DROUGHT OF 1999-2000, Joseph D. Davidson [*] and Curtis L. Hollabaugh, Geosciences, State University of West Georgia, Carrollton, GA 30118. The Little Tallapoosa River is critical to the future growth and development of Carroll County. Villa Rica obtains some of its drinking water and discharges treated sewage into a tributary stream (Mud Creek). Carrollton has a spray field application site adjacent to the Little Tallapoosa River. Three of its tributary streams are impaired (Mud Creek, Buck Creek, and Buffalo Creek). The river flows through the city of Carrollton and through productive farmland that makes Carroll County the second leading producer of beef cattle in the state of Georgia. The river is impaired from where Buffalo Creek joins it to the Georgia-Alabama state line. During the summer of 2000 the river was further stressed because of the drought of 1999-2000. Field checks indicated that first its tributaries and then the river were transformed from free flowing into a series of stagnate pools by proliferation of beaver dams. Water quality changes associated with this were lower DO, higher TDS and transformation from semi-clear water to brown-colored turbid water.
9:15 WEST GEORGIA WATERSHED ASSESSMENT: PRELIMINARY WATER QUALITY RESULTS OF HEARD AND CARROLL COUNTY GEORGIA, Curtis L. Hollabaugh, Geosciences, State University of West Georgia, Carrollton, GA 30118. Field checks of major streams in Carroll and Heart Counties were done during the summer and fall of 2000. The field checks (123 for Carroll and 46 for Heard County) were conducted at each public access point for each significant stream in both counties (excepted is the Chattahoochee River). Field checks are vital to determine the best locations for long-term monitoring. A satellite image coupled with field checks assisted in determination of land usage that potentially impacts water quality. Water quality parameters measured in the field were temperature, dissolved oxygen (DO), pH, and total dissolved solids (TDS). Rapid colorimeter laboratory measurement of nitrate-N was done on all samples. Silica, iron and sulfate determinations were done on selected samples. Extreme values found during the field check were DO = 1.6 ppm (stagnant waters), TDS = 518 ppm and rntrat[sim]N = 5.3 ppm (downstream of treated sewage discharge point).
9:30 TRENDS IN THE WASHINGTON, D.C. URBAN HEAT ISLAND, 1945-1998, Troy Knight [*], Georgia State University, Atlanta, GA 30305. Temporal and spatial trends in the Washington, D.C. urban heat island are investigated using weather station data from the Global Historical Climate Network. Fourteen Stations within the Washington-Baltimore Metropolitan area are utilized covering a time period, with some variations between 1945 and 1998. Temporal variation patterns are analyzed from 1945, 1963, and 1986 to 1998. The majority of stations display an increasing difference with respect to the central Washington station. However, a few stations show a narrowing of the gap allowing study of the development of the heat island in suburbanizing areas.
10:00 Business Meeting
Melanie L. DeVore, Presiding
10:30 TEMPORAL VARIATION IN THE ENVIRONMENTAL RADIATION OF COASTAL SOILS OF GEORGIA, Gian S. Ghuman, Kailash Chandra and Kenneth S. Sajwan, Savannah State University, Savannah, GA 31404. Radioactivity of soil samples collected from seven sites in the Savannah area was measured during the years of 1997 and 2000. The objective was to determine if there were any changes in the natural radiation status of these soils. Samples were collected from each site with three depths: 0-3 cm, 3-10 cm and 10-20 cm. Soils were air-dried and passed through 2 mm-sieve. Radioactivity was measured in the weighed amounts of soils using Geiger Counter Model 500 (Tennelec/Nucleus, Inc.). Results showed a slight increase in radioactivity of these soils over a period of three years. Radioactivity appeared to be associated with the fine-textured (high clay content) top or bottom soils of different sites. Clay particles with greater radioactivity are formed from the decomposition of feldspars and micas that contain a large fraction of e arth's potassium-40. As observed earlier, the observed radiation is mainly due to gamma rays.
10:45 MEASUREMENT OF LOWER TROPOSPHERE TEMPERATURE PROFILE WITH A SIMPLE 433 MHZ. ROCKETSONDE, David J. Babulski, Snellville, GA 30078. Measurement of the temperature gradient of the lower troposphere to 1000 meters from Whitesburg, Georgia on August 13, 2000, using a single channel 433 Mhz. Rocketsonde, showed a temperature decrease of 5.2 degrees F per 300 meters. This is consistent with the theoretical dry adiabatic lapse rate. This project was completed as a voluntary science enrichment activity with middle and high school students in Georgia. To date over 560 students have participated in the project.
11:00 ANALYSIS OF HISTORIC TEMPERATURE DATA OF SELECTED U.S. CITIES, Austine O. Nnaji, Valdosta State University, Valdosta, GA 31698. Mean historic temperature was examined using Time Series Analysis (TSA) to determine significant oscillations. Input includes time series of selected U.S. cities with 100 years of data spanning from 1900 to 1999. Explanations on patterns revealed by the series plot were endeavored on decadal scale, emphasizing exponential smoothing of the fluctuation yielded. Trend fitting for the entire spectrum indicates slight upward direction with 4.26 degree C difference between highest and lowest mean annual values. The annual mean change in each decade shows downward trend in the first six decades albeit upward in decades 3 and 4; and a sustained upward trend in the last two decades (1980-1999). These patterns largely coincide with recent warming elsewhere in the world. Results indicate a cycle at 48 to 50 years with seasonal effects, of which the 10 to 12 year season is significant. Thu s, hinting the duration of current warming.
11:15 WATER QUALITY OF THE LOWER MUCKALEE CREEK AND ITS TRIBUTARIES IN SUMTER AND LEE COUNTIES, GEORGIA, Md. Khalequzzaman, Department of Geology & Physics, Georgia Southwestern State University, Americus, GA 30917. The lower Muckalee Creek and its tributaries flow through predominantly agricultural areas. Monthly monitoring of water temperature, pH, conductivity, total suspended solid, total dissolved solid, dissolved oxygen, nitrate, and phosphate was carried out at six locations in the lower Muckalee Creek watershed for a period of several months during the Summer and Fall of 2000. Nitrate and Phosphate were measured in the laboratory using a digital Spectrophotometer. Other parameters were measured in the field. The purpose of this study was to assess the impact of various land-use practices within the watershed, urban facilities located upstream, and seasonal variations on water quality parameters. The results show an increase in the amount of nitrate and phosphate at sampling locations situated downstre am of a sewage treatment plant, as well as downstream of dairy farms. It appears that the prolonged drought that existed during the Summer-Fall of 2000 had an adverse impact on the amount of dissolved oxygen and pH.
11:30 EARLY RADIATION OF ASTERACEAE (SUNFLOWER FAMILY): OUT OF AFRICA? Melanie L. DeVore, Georgia College and State University, Milledgeville, GA 31061. The fossil history of Asteraceae (Sunflower Family) has been based mainly on palynological data. Despite the lack of strong, direct, fossil evidence, trends in fossil flowers, the distribution of the closest families related to Asteraceae, and tectonic histories have been utilized to estimate a Middle to Late Eocene age for the family. Ancestral area analyses (Bremer, 1992) have suggested that Asteraceae had an ancestral area consisting of the Pacific and South America. Ancestral area analyses of tribal level phylogenies for the family strongly suggest that Africa played a key role in the early evolution of the family. Based on these results, biogeographical data from other groups, origin and position of anomalously thick oceanic crust, and Oligocene sea levels, it appears that Asteraceae may have radiated from South America to Africa. In November 2000, Paleocene-Eocene fossil palynomorphs assigned to Asteraceae were reported from South Africa (Zavada and de Villiers, 2000). It is still questionable whether these grains represent Asteraceae or Anthemoid pollen from a closely related family.
11:45 PALYNOLOGY OF THE HAGERMAN FOSSIL BEDS NATIONAL MONUMENT, HAGERMAN, IDAHO, Eddie B. Robertson, Reinhardt College, Waleska, GA 30813. Hagerman Fossil Beds National Monument in the Snake River Buttes near Hagerman, Idaho is best known for the Hagerman horse, Equus simplicidens, a late Pliocene (3.5 million years ago) zebra-like species, extensively quarried from the locality since the 1930s. An inquiry was made into the microflora of the aquicludes 200 feet stratigraphically below the deposits that contain the horse quarry (approximately 3100 feet elevation). Five carbonaceous paper shale samples were taken from the aquiclude stratigraphically equivalent to the fossil bearing quarry beds. Samples were processed by standard palynological techniques. Forms present indicate oligotrophic fresh water, with water lilies and accompanying epiphytic algae. The epiphytic diatoms indicate the presence of cold clear water associated with primary order streams and ponds. Grass pollen associated with local grasslands a nd probable regional wind transport of bissacates indicate the presence of nearby coniferous stands.
GEORGIA SOUTHERN UNIVERSITY: MAPPING THE CAMPUS AND STUDENT SAFETY AFTER DARK, Anna Austin [*], William Brooks, Karen Oser, Angela Page, Emily Polonus, Russel Smith, Brandi Walzer and Susan Langley, Georgia Southern University, Statesboro, GA 30460. Paper maps convey information about real-world features or population for a particular point in time. Digital maps, and the accompanying digital database, allow for interactive mapping and display of spatial data through time. Current digital maps of the Georgia Southern University campus features were required to perform a "lighted area" analysis of the campus. Well-lit areas offer students more security after dark. We first converted the existed computer aided design (CAD) files into a geographic information system (GIS) format. Errors in the CAD files were corrected, files were updated, and feature attributes added using ArcInfo and ArcView GIS software. Our final products include two-dimensional (2-D) and three-dimensional (3-D) maps of the campus, in addition to the lighting analysis. The use of a campus GIS will facilitate future map revisions and new features like new buildings may be easily included. Three-dimensional maps aid in visualization, skyline changes, and vertical distribution analysis.
MINERALS OF THE WOLF CREEK FORMATION, NORCROSS QUADRANGLE, GWINNETT COUNTY, NEAR DULUTH, GEORGIA David Babulski, Georgia Mineral Society, Atlanta, GA 30333-5011. Fifteen mineral species have been described in the Wolf Creek Amphibolite body. These mineral species described are: Hornblende, Epidote, Piemontite, Chabazite, Prehnite, Pyrite, Chalcopyrite, Clinozoisite, Dravite var Tourmaline, Chlorite, Garnet var Almandine, Sulphur (as free crystals), Calcite, Kaolinite, Hyalite Opal. Several of these mineral species are new to Gwinnett County. Project completed as a part of the Georgia Mineral Heritage Project.
PALYNOSTRATIGRAPHY OF THE SIMPSON TEST WELL #1, NPRAALASKA, Eddie B. Robertson, Reinhardt College, Waleska, GA 30183. Sixty-five dinoflagellate and one hundred and twenty-five pollen and spore taxa are reported from the Grandstand, Torok, "Pebble Shale," Kingak, and Sublik Formations in the Simpson Test Well #1, National Petroleum Reserve of northern Alaska. Intervals are dated as Early to Middle Albian, Aptian?, Barremian, Valanginian, Jurassic, and Triassic. The ages were determined by the use of concurrent ranges of the forms reported. Presence-absence, relative abundance, and diversity indices were used to interpret depositional environments. Agglomeration techniques were useful in delimiting palynomorphic assemblage zones.
Section IV: Physics, Mathematics, Computer Science and Technology
Room SB 274
A. Lazari, Presiding
8:00 WIDEBAND PHOTOELECTRIC MAGNITUDE MEASUREMENTS OF THE PLANETARY NEBULAE NGC 2392, NGC 3242, NGC 6543 AND NGC 6720, Richard W. Schmude, Jr. and Prital Mehta [*], Gordon College, Barnesville, GA 30204. We have used an SSP-3 solid state photometer along with a 0.51 meter Newtonian telescope and filters that closely match the Johnson U, B, V, R and I system to measure the brightness of 4 planetary nebulae. The resulting apparent magnitudes are: NGC 2392: (U = 9.29, B 9.66, V = 9.00, R = 9.45 and I = 9.90), NGC 3242: (B = 9.03, V - 7.98), NGC 6543: (U = 9.00, B = 9.00, V = 8.14, R = 8 39 and I = 9.06) AND NGC 6720: (B = 9.91, V = 8,79, R = 8.60 and I = 9.83). The color peaks in the V filter for NGC 2392 and NGC 6543 but it peaks in the red for NGC 6720.
8:15 ALPHA DECAY MODEL PROPOSAL USING A NON-SQUARE PODENTIAL MODEL NEAR THE NUCLEUS, Leighton Arnold [*] and J.E. Hasbun, Department of Physics, State University of West Georgia, Carrollton, GA 30118. In this presentation, a model is proposed to consider Alpha decay in similar way as is presented in standard quantum mechanics texts, however we propose to include a Yukawa type of potential, rather than a square barrier at small distances from the nucleus. For larger distances, the standard coulombic repulsive term is included. We investigate the conditions for which such model is applicable. In particular we vary the parameters of the model in order to produce the needed barrier on whose height depends the probability of decay.
8:30 ANALOGY OF BLACK BODY RADIATION TO SOUND, Ryan Schwartz [*] and J.E. Hasbun, Department of Physics, State University of Wet Georgia, Carrollton, GA 30118. We look at the commonly known concept of blackbody radiation and incorporate phonons rather than photons. We find that the results are very similar to those found in blackbody. The results obtained indicate, however, that the relationship between power and temperature involves a constant, different from the Stefan-Boltzman universal constant, as should be expected. Similarly, Wien's displacement law involves a phonon based constant that is different from the standard one applied to blackbody radiation. It seems that sound might behave in a similar fashion as light does regarding the above mentioned analogy. We discuss our results and provide some insight into what our results seem to represent in our everyday experiences.
8:45 ONE-DIMENSIONAL, CONVECTIVE-CONDUCTIVE HEAT TRANSPORT THROUGH A POROUS MEDIUM, J.E. [Hasbun.sup.1] and J. [Mayer.sup.2] [*], [Department.sup.1] of Physics and [Department.sup.2] of Geosciences, State University of West Georgia, Carrollton, GA 30118. Energy can be transported through a permeable porous medium by conduction through solid and fluid phases, and by bulk motion of pore fluid convection. Depending upon fluid flow velocity and thermal properties of the medium and fluid, the relative importance of advection and conduction will vary. We obtain the one-dimensional temperature distribution equation for transient energy transport and steady-state fluid flow through a water-permeable porous medium. We also obtain an analytical solution for a special case of one-dimensional fluid flow. The solution is used to explore the effects of different convective-conductive system properties. Finally the solution is applied to a case of groundwater flow adjacent to the Little Tallapoosa River in Carrollton, Georgia to test alte rnative hypotheses explaining surface-water groundwater interaction.
9:00 LOW COST INNOVATIVE PHYSICS EXPERIMENTS, V. Anantha Narayanan, Savannah State University, Savannah, GA 31404. Details of innovative Physics laboratory experiments in optics and sound will be described. These deal with low cost refractometers, verification if inverse square law of light intensity using Airy's Disk, and determining the speed of sound in the tuning fork metal. Liquid lenses were made by fashioning the convex transparent plastic cap of a can of clearsil face wash to fill in the selected liquids and making a plano convex lens out of this by using a microscope slide as a cover. The lens maker's formula and the thin lens equation were used to calibrate the refractometer, which measured the refractive indices within 2%. Hollow prisms and minimum deviation method was involved in the liquid prism sucrosemeter which measured the sugar concentration within 1-2% by weight. Airy's Disk areas and intensities as a function of distance of circular hole to screen were used to verify the inverse square la w of light intensity. The tuning fork formula gives the frequency as a complicated function of the length, and thickness of the prong, young's modulus of tuning fork metal, and the appropriate radius of gyration. Expressions relating wavelength, velocity and frequency are arranged. Using tuning forks of known frequencies, the speed of sound in the tuning fork metal are evaluated with 4% of accepted values.
9:15 NEGATIVE IMAGINARY MASSES FROM GENERAL RELATIVITY, Russell Akridge, Kennesaw State University, Kennesaw, GA 30144. Using standard general relativity techniques to generalize familiar electromagnetic and particle field equations can produce the negative infinitesimal imaginary terms and masses required for forward time propagation Usually, these terms are simply inserted, ad hoc, with the justification being that they are necessary additions to insure forward propagating fields. This study shows that these arrow-of-time terms can be a natural result of appropriately generalized field equations, and even provides an estimate of the actual finite, but very tiny, magnitude of these necessary dimensionless terms, which turn out to be related to the expansion of the universe.
9:30 COMPUTER-BASED CELL PHONE BATTERY TESTING SYSTEM, Ben de Mayo, State University of West Georgia, Carrollton, GA 30118. A semi-automated system for testing cell phone batteries has been designed, constructed and used for over a year to test the charge-discharge qualities of cell phone batteries. The system consists of a load resistor of 10 [omega] with a temperature monitor, a voltage comparator circuit to detect when the cell's voltage dropped below 3 volts, and a switching relay with a transistor driver and protection diode. The cell's voltage and discharge current were continuously monitored and recorded to the computer for preselected times up to 24 hours. The system was monitored and controlled with Vernier's Logger Pro software. The batteries performed admirably. After 319 cycles taking place over a period of 15 months, one cell was still operating, even though its output had dropped 43%. Research was supported by NAK Industries and the Georgia Space Grant Consortium-NASA.
9:45 IMES OF THE U.S.A., Ronald E. Mickens, Clark Atlanta University, Atlanta, GA 30314. Most histories of quantum physics place great emphasis on its theoretical formulations and how they gave rise to the now accepted theory of quantum mechanics. A major consequence of this viewpoint is its stress on the work of theoreticians, e.g., the papers and related thoughts of Planuck, Einstein, Bohr, Heisenburg, Schrodinger, deBroglie, and Dirac have been studied in great detail. Our position is that role of experiment should be placed on an equal footing with theory in regard to the genesis and elucidation of quantum mechanics. The area of experimental science that contributed the most significant results was molecular spectroscopy. In particular the work of Elmer S. lines on the rotational-vibrational spectra of diatomic molecules had a major impact on atomic physics during the period 1919-1922. We present lines' work, give a summary of its influence on molecular physics, and discuss his subsequent career after le avina the University of Michigan where he received his doctorate in 1918.
10:00 Business Meeting
10:30 A NONSTANDARD FINITE DIFFERENCE SCHEME FOR THE LOTKA-VOLTERRA PREDATOR-PREY MODEL, Kale [Oyedeji.sup.1] and R.E. [Mickens.sup.2], [Morehouse.sup.1] College, Atlanta, GA 30314 and [Clark.sup.2] Atlanta University, Atlanta, GA 30314. The lokta-Volterra prey-predator equations are generally used to model the evolution of two interacting biological species. Most finite difference schemes do not produce the proper periodic solutions behavior about the nontrivial fixed-point where both populations can co-exist. In particular, standard schemes lead to numerical solutions that either spiral into or out of this fixed point. Using nonstandard techniques, we construct a scheme that has the same dynamical properties as the coupled differential equations. Our results are illustrated by plotting a variety of numerical solutions for a range of parameter values: initial conditions ([x.sub.0], [y.sub.0]) and step-size, h. The general conclusion is that nonstandard methods can resolve many of the difficulties that may arise in the const ruction of discrete models for differential equations. Supported in part by Morehouse College Wallestein Faculty Research grant and by grants from DOE and MBRS-SCORE.
10:45 EXPERIENCE IN TEACHING AN ONLINE COLLEGE ALGEBRA COURSE, Andreas Lazari and Kathy Simons, Valdosta State University, Valdosta, GA 31698. In this paper, we discuss our first hand experience in making an online college algebra class successful for both students and instructors. We start by controlling the population of students that register for the class. General guidelines were made for material completion and test-taking. Students made appointments to discuss progress with the professor. These requirements helped make this online course in college algebra successful.
11:00 MOISTURE AND MICROORGANISM GROWTH IN CARPET, Hubert B. [Kinser.sup.1], Johannes [Leisen.sup.2], Haskell [Beckman.sup.2], Amanda [McGhee.sup.3] and Karen [Leonas.sup.3], [Dalton.sup.1] State College, Dalton, GA 30720, [Georgia.sup.2] Institution of Technology, Atlanta, GA 30332 and University of Georgia , Athens, GA 30602. The distribution of moisture absorbed by tufted carpet and the binding strength of the water molecules to the fibrous substrate were measured with nuclear magnetic resonance (NMR) techniques. These results were connected with microorganism growth studies in which carpet samples were inoculated with different types of fungi. Studies of the water activity, [a.sub.w], for three types of carpet structures exposed to moisture, as well as transverse relaxation time constants, [T.sub.2], led to correlations with microorganism growth results. Those carpet structures with more strongly bound water, in general, supported less microorganism growth than those with the less strongly bound moisture. This work was supported by CCACTI.
11:15 SPECIFIC GRAVITIES OF TEKTITES FROM GUANGDONG, CHINA, Richard W. Schmude, Jr., Gordon College, Barnesville, GA 30204. The specific gravity of 288 tektites from Guangdong, China were measured and the mean specific gravity is 2.426. (Tektites are glassey rocks that are believed to have formed as a result of meteorite impacts on the Earth.) The range of specific gravities for Guangdong tektites is intermediate between that of tektites from Dalat, Vietnam and Billiton Island, Indonesia. The relationship between specific gravity and both tektite mass and surface to volume ratio has been investigated. The specific gravities of the 49 disc-shaped Guangdong tektites measured in this study obey the equation: Specific Gravity (20[degrees]C) = 2.4419 = 0.00914 [log.sub.10] [M.sub.A] where [M.sub.A] is the tektite mass in grams. This equation is consistent with the higher specific gravities of microscopic tektites.
11:30 TACTILE FORCE SIMULATION IN PHYSICS, K.C. Chan, Albany State University, Albany, GA 31705. It is now possible to stimulate tactile force without using expensive gear such as a virtual reality cave and glove. An inexpensive force-feedback mouse will do the job adequately. The simulated tactile force could be very effective in teaching abstract concepts such as force and work. To illustrate its effectiveness, several Java applets were developed to simulate gravitational force, spring force as a function of spring constant and distance, surface tension as a function of film width, and buoyancy force as a function of volume. Not only could students learn about these forces from equations, they could actually feel these forces. The absolute force derived from a force-feedback mouse is only a few ounces; the simulated forces are thus relative in magnitude. To get the correct force magnitudes one still has to perform experiments in the lab. Besides teaching the force concept, the force-feedback mouse is also great for teaching more difficult concepts such as potential difference and potential energy. Other possibilities will be shared in the presentation.
Section V: Biomedical Sciences
Room AB 107
Mark Maloney, Presiding
8:00 THE MEASURING OF PORE AREAS IN VINYL STYRENE DISCS USING SCANNING ELECTRON MICROSCOPY AND MORPHOMETRIC TECHNIQUES, Aaron James, Mercer University, Macon, GA 31207. The purpose of this study was to determine areas occupied by pores in Vinyl Styrene (VS) discs by using scanning electron microscopy (SEM) techniques and morphometric techniques and to quantify pore areas of VS discs. These discs are being studied to see if they can be used as scaffolding for bone growth. This study used three VS discs. The discs were scanned in a scanning electron microscope using a voltage of 5 kV and a spot of 3 with a magnification between 29 and 32 times. Pictures were saved of the scanning pictures that were taken and then brought into Image-Pro Plus computer program. Once pictures were brought into the program pore areas were selected automatically by setting a threshold value for the program and allowing the computer to automatically count these areas. The sizes of the areas were recorded and analyzed in a spreadsheet program. It was found out that most pores are between the size of 100 and 10000[micro][m.sup.2] and that there are few pore areas that are between 10 and 100[micro][m.sup.2].
8:15 CONSTRUCTION OF SACCHAROMYCES CEREVISIAE YPR1 18W FUSION PROTEIN, Krystal Hudson [*] and Jung H. Choi, The Georgia Institute of Technology, Atlanta, GA 30332. The vector PSDRED1-N1 contains a gene that codes for a red fluorescence protein, RFP. This RFP can be used to create fusions to proteins of interest. With the help of restriction endonucleases, this RFP gene was cut from the vector, PDSRED1-N1, and ligated into pUGpd, a yeast expression vector. Using cloning techniques, a successful clone with the gene for RFP in the pUGpd was found. Using this new construct, YPR11SW, a yeast protein thought to be involved in sporolation, will be fused to the RFP. A transformation protocol will allow for a specific strain of yeast to obtain a copy of this fusion in its genome. The binding of these two genes will aid in detecting the localization of the YPR118W gene in the yeast by using fluorescence microscopy. Determining the localization of YPR118W will hopefully help uncover a function for this gene.
8:30 PHARMACOLOGICAL CHARACTERIZATION OF PURINERGIC RECEPTORS IN CULTURED GUINEA PIG GALLBLADDER EPITHELIAL CELLS, LaShauna Evans [*], Oluwakemi Abdulkadir, Latanya Hammonds-Odie and Pamela Gunter-Smith, Department of Biology, Spelman College, Atlanta, GA 30314. In a primary culture system of guinea pig gallbladder epithelial cells ATP causes a transient increase in transepithelial potential (V.sub.t) and short-circuit current ([I.sub.sc]). ATP modulates cell ion transport via a family of purinergic receptors in various tissues. However, determination of the receptor subtype mediating ATP responses is complicated by the lack of specific agonist and antagonist. The presence of a particular subtype is generally deduced from the rank potency of the response to ATP, UTP and nucleotide analogs. The ATP response in the cultured cells is strongly activated by ATP and insensitive to UTP suggesting the presence of either [P2Y.sub.1] or [P2Y.sub.11] receptors. In this study, we have used two other ATP analogs to distingu ish between these purinergic receptor subtypes. Like ATP, 2-MeSATP transiently increased [V.sub.t] and [I.sub.sc]; whereas, [alpha],[beta]-MeATP had no effect. These results suggest that [P2Y.sub.11] is the purinergic receptor subtype in cultured guinea pig gallbladder epithelial cells mediating the effect of ATP on ion transport. This work was supported by NIH grants GM08241 and RR1 1598. L.E. was supported by Howard Hughes Medical Institute (71196-529802) and the William Townsend Porter Foundation. L.H-O. was supported by Model Institutions for Excellence/NASA Cooperative Agreement number NCC8-179.
8:45 HISTAMINE DOES NOT ELEVATE INTRACELLULAR CALCIUM LEVELS IN CULTURED GUINEA PIG GALLBLADDER EPITHELIAL CELLS, Kimberly Duhart [*], Oluwakemi Abdulkadir, Latanya Hammonds-Odie and Pamela Gunter-Smith, Spelman College, Atlanta, GA 30314. The gallbladder is an absorptive epithelium, which stores and concentrates bile. Cultured guinea pig gallbladder epithelial cells are very similar to the native tissue, which makes it an excellent model for gallbladder ion transport studies. We have shown that histamine causes a biphasic increase in [I.sub.sc], probably by activation of anion secretion. There are a variety of signal transduction systems that contribute to the regulation of membrane transport in gallbladder epithelial cells. In this study, we focused on whether calcium serves as the second messenger mediating the response to histamine. The effects of histamine on intracellular calcium were accessed from changes in fluorescence with the calcium indicator dye Fluo3, monitored by the Cytofloor Series 4000. The levels of intracellular calcium were quantified to determine if calcium is the second-messenger pathway by which histamine works. Funding provided by NIH grants GM08241 and RR11598. K.D. was supported by NIH grant GMS60566. L.H.-O was supported by Model Institutions for Excellence/NASA Cooperative Agreement number NCC8-179.
9:00 TYPE I COLLAGEN AS A MARKER FOR LEIOMYOMA PROGRESSION, Fatima McKindra [*], Eniki Mack, Tammy Wallace, Jobnafel Crowe and Shelia McClure, Spelman College, Atlanta, GA 30314. Uterine leiomyomas (fibroid tumors) originate from the myometrial layer of the uterus. They typically affect women during their reproductive years and are more prevalent in African-American women than any other ethnic group. Work in our laboratory has suggested that the level of type I collagen in the extracellular matrix of leiomyomas is correlated with their growth potential. The purpose of this work was to determine if the differences in type I collagen observed in the matrix occur as a result of a change in type I collagen gene expression as tumors progress from a growth-arrested to an activity growing state. Cells from growth-arrested (HT1) and actively growing tumors (ST1) were monitored for type I collagen expression utilizing Western Blots. Datasuggest that the expression of type I collagen is upregulated in cells derived fr om the growth-arrested tumors (HT1), and corresponds with increases in type I collagen in the extracellular matrix of these cells as monitored by ELISA. This supports the use of type I collagen expression as a marker for leiomyoma progression. (Supported by a grant from NIH-RIMI RR11598.)
9:15 THE EXPRESSION OF CELL CYCLE REGULATORY PROTEINS DURING UTERINE LELOMYOMA PROGRESSION, Erika Carr [*], Kristal Frand, Tammy Wallace, Johnafel Crowe and Sheila McClure, Spelman College, Atlanta, GA 30314. Leiomyomas are characterized by periods of unregulated growth, which are usually followed by secretion of a collagenous matrix and growth arrest. However, these quiescent tumors may resume their growth. The purpose of this study is to determine the roles of cyclin-dependent kinases (cdk) and the cdk inhibitor p21, in regulating the growth of these tumors. Cell lines derived from growth-arrested tumors (designated HT1) and those derived from actively growing tumors (designated ST1) were monitored for both cdk and p21 expression utilizing immunohistochemistry and Western Blots. Data suggest that the expression of p21 is, and remains, up-regulated in cells derived from the growth-arrested tumors (HT1). Moreover, levels of p21 in cell line HT1 are higher than that of the normal myometrium. In cell line HT1, cdk expression is down regulated relative to the other cell lines. These results suggest that progression of these tumors from the proliferative to the growth-arrested state and vice versa may involve changes in the expression of these cell cycle regulatory proteins. Supported by a grant from NIH-RIMI PRR1 1598.
9:30 HORMONAL REGULATION OF KERATINOCYTE TRANSGLUTAMINASE (KTG) mRNA AND PROTEIN IN RAT UTERINE AND VAGINAL EPITHELIA, Karenne N. Fru and Wanda T. Schroeder, Wesleyan College, Macon, GA 31210. Deratinocyte transglutaminase (KTG) is known to be expressed only in differentiated cell layers in human epidermis. The expression of this differentiation-specific protein has not been examined in hormone-responsive epithelia such as uterine and vaginal epithelia. Our studies, performed in ovariectomized rats, examined KTGmRNA levels at varying time points after administration of exogenous estrogen. Northern blot analysis revealed that KTGmRNA expression is absent in both rat vaginal and uterine tissue before exposure to estrogen. However, soon after administration of estrogen, KTG mRNA levels increased dramatically with an over 300-fold increase at 18 hours post-injection. Indirect immunofluorescence microscopy with an anti-KTG monoclonal antibody further demonstrated differences in KTG protein expression before and af ter exposure to estrogen. Our findings establish that KTG mRNA and protein expression are not only differentially regulated in epidermis, but also in uterine and vaginal epithelia in response to estrogen.
9:45 CIPROFLOXACIN-BISPHOSPHONATE ANTIBIOTIC: RELEASE FROM Ca[PO.sub.4] GRANULES AND ANTIBACTERIAL EFFECT, Kim [Jerome.sup.1] [*], Phyllis D. [Brewer.sup.2], Brian [Shapiro.sup.2], Linda [James.sup.1], James C. McPherson, [III.sup.2] and Thomas B. [Buxton.sup.2], Paine [College.sup.1], Augusta, GA 30901 [and.sup.2Elscnhower] Army Medical Center, Ft. Gordon, GA 30905. An experimental combinational drug, ciprofloxacin linked to "bone-seeking" biphosphonate, (E41) may have value for traumatized bone infection. We tested Ca[PO.sub.4] granules (Skelite[TM], Millennium, Biologix, V3), bound to E41 (ElizaNor Biopharmaceuticals, [K.sub.d] = [10.sup.-7] M) for reversible release of biologically-active antibiotic from E41-V3. A petriplate bacterial lawn, streaked with E. coli, received washed E41-V3 in an agar well. After incubation (18 h, 37[degrees] C) release of E41 (or parent ciprofloxacin), from V3, was shown (33 mm zone of inhibition). Characterization of drug was done by acid elution (10 mM [h.sub.3][PO.sub.4], 30 s) of E41-V3 and addition of buffered V3. Supernatants were assayed for drug specific fluorescence. Intact E41 was present, based upon an ability to rebind V3 (bisphosphonate-mediated). % Bound: #ra, 43.3[+ or -]6.5% vs. equimolar ciprofloxacin as control, 12.7[+ or -]3.1%, p,0.01. Intact E41 was released from Skelite[TM], it maintained its antibiotic property and rebinds bone-like mineral.
10:00 Business Meeting
10:30 NITRIC OXIDE LEVELS MODULATE THE INDUCTION OF ANGIOGENESIS BY BREAST CANCER CELLS, Tijuana Moss [*], Debra Ellerson and Gary L. Sanford, Morehouse School of Medicine, Atlanta, GA 30310. Nitric oxide (NO) have been shown to play a role in mediating the ability of angiogenic factors to induce the formation of blood vessels. High levels of NO may lead to toxicity or induce apoptosis, which has previously been suggested as a means to control growth. We will examine this possible role of NO using breast cancer cell (grown as monolayer or in 3-dimensional culture in a horizontally rotating bioreactor) conditioned-media (CM). Control CM will also be collected from normal mammalian cells. Angiogenesis will be assessed with human umbilical endothelial cells (HUVEC) grown in microcarrier cultures. Briefly, HUVEC/beads will be embedded in collagen gels and exposed to the various CM's or to control medium with or without a nitric oxide donor (SNAP). Over a period from 24 to 72 hr, cells will either form capillary-l ike outgrowth of single cells migrating off the beads. Positive angiogenesis will be the formation of numerous capillary-like structures. We expect that elevated levels of NO produced from SNAP will modify the angiogenic response of HUVEC, in our 3-dimensional model, to CM from breast cancer cells. Furthermore, breast cancer cells grown in 3-dimensional culture may produce CM with a lower angiogenic response, due to increased NO production induced by the 3-dimensional culture system. Supported by grants: NIGMS S066GMM08248, NASA NCC 9-53 and NAG8-1636.
10:45 THE ROLE OF Fc RECEPTOR-MEDIATED IMMUNE EFFECTOR PROCESSES IN CHLAMYDIAL CLEARANCE IN MICE, Terri Moore [*], Francis Eko, Goodwin Ananaba and Joseph Itietseme, Morehouse School of Medicine, Atlanta, GA 30310. To produce a vaccine requires a detailed understanding of the role of both humoral and T cell-mediated immune responses in protective immunity. Because Chlamydia is an obligate intracellular pathogen, the FcR-mediated phagocytosis and intracellular killing of infected cells and elementary bodies is a plausible mechanism of antibody action in addition to neutralization of infectious elementary bodies released during an infection. To investigate whether FcR-mediated immune effector mechanisms (i.e. immune phagocytosis, ADCC and NK activity) play a role in host defense against chlamydial infection, FcR-knockout (KO) mice were analyzed for their ability to control genital chlamydial disease as efficiently as wild type mice. In the primary infection, the intensity of the disease (measured by shedding of chlamydiae in the genital tract) was comparable during the first 3 weeks after infection in both FcR-KO and control mice. However, FcR-KO mice suffered a significantly greater disease at the later stages of the infection and during the secondary infection. The greater disease suffered by FcR-KO mice appeared to be due to the deficient FcR-mediated immune effector processes among leukocytes from these mice. The results indicated that specific anti-chlamydial antibodies may contribute to host defense against Chlamydia via FcR-mediated immune effector mechanisms.
11:00 THE EFFECT OF PSC-833 ON RAT LIVER DNA SYNTHESIS INDUCED BY 2/3 PARTIAL HEPATECTOMY, Robbyn [Tompkins.sup.1], D.S.R. [Sarma.sup.2] and Olatunde [Okediji.sup.3], [Fort.sup.1] Valley State University, GA, [University.sup.2] of Toronto, Canada and [Albany.sup.3] State University, Albany, GA 31705. In vitro experiments indicate that PSC-833, a non-immunosuppressive cyclosporin derivative, interacts directly with P-glycoproteins (P-gh) with high affinity. Studies in multidrug resistant tumor models confirm P-gh as the in vivo target of PSC-833 and demonstrates the ability of PSC-833 to inhibit liver cancer development in mice. To determine whether PSC-833 is inhibiting DNA synthesis in rat liver, two experiments were performed with male fisher rats. Experiment 1 (Control), 4 rats were given a basal diet containing 0.645 g/kg PSC-833. In experiment 2, 16 rats were divided into 3 groups and treated for 4 days with a basal diet of 0.175 g/kg PSC-833 (6 rats), 0.645 g/kg PSC-833 (6 rats) and 4 rats served as untreated controls. Partial hepatectomy was performed to induce cell proliferation. DNA content was determined using thymidine as a radioactive marker and Burton's colorimetric estimation of DNA content. Data obtained indicate an inhibition of DNA synthesis in PSC-833 treated rats.
11:15 EXPRESSION OF CHEMOKINE AND CHEMOKINE RECEPTOR GENES IN CHLAMYDIA INFECTED CELLS, G. [Ananaba.sup.1] [*], F. [Eko.sup.2], T [Belay.sup.2], T. [Walker.sup.1], T. [Moore.sup.2] and J. [Igietseme.sup.2], [Spelman.sup.1] College and [Morehouse.sup.2] School of Medicine, Atlanta, GA 30314. Chlamydia is the most common sexually transmitted bacterial disease in the USA and it poses a potential threat to human reproduction and well-being. Studies have shown that T cell-mediated immune responses, involving the induction and recruitment of T helper type 1 (Th1) cells into the genital mucosa is crucial for Chlamydia immunity. Chemokines and their receptors are important mediators of leukocyte trafficking and recruitment during host defense and inflammation. In this study RT-PCR was used to analyze the expression of chemokine and chemokine receptor genes during genital chlamydial infection. Kinetic studies revealed enhanced levels of RANTES, MCP-1, IP-10, MP-1 and ICAM01 expression after infection. These molecules peaked between 7 to 21 days after infection and decreased by day 42 post-infection. These results demonstrated that genital chlamydial infection is associated with a significant induction of chemokines and chemokine receptors that are involved in the recruitment of Th1 cells into the genital tract. Moreover, regulation of these molecules is likely to be important in the acquisition and maintenance of immunity against Chlamydia. Partially supported by Spelman College, RIMI, MIE and Howard Hughes programs.
Friday March 23, 2001 - Saturday, March 24, 2001
Authors should be present Saturday between 10:00 - 10:30
CDNA ARRAY ANALYSIS OF EXPRESSION CHANGES INDUCED BY TRYPANOSOMA BRUCEI INFECTION IN BRAIN, Jonathan Stiles, John C. [Meade.sup.1], Zuzana Kucerova, Joseph Whittaker, Winston Thompson, Deborah Lyn and George [Hill.sup.2], Morehouse School of Medicine, Atlanta, GA 30310, [Department.sup.1] of Microbiology, University of Mississippi Medical Center, Jackson, MS, 30216 and [Department.sup.2] of Microbiology, Meharry Medical College, Nashville, TN 37208. Trypanosoma infection induces various degrees of brain pathologies. However, the sequelae and extent of these pathogenic brain effects is unclear. Anti-parasitic drugs may eliminate the causative agent. However, the brain damage can only be determined in postmortem autopsies. We evaluated the gene expression changes induced by T. brucei infection in mouse brain by cDNA array analysis and validated genes of interest by quantitative RTPCR and immunohistochemistry. Neuroleukin was significantly upregulated and immunolocalized in the locus coeruleus during the terminal stages of T. b rucei infection. Protein kinase B (PKB) and calcium-binding protein MHR23A were downregulated. We conclude that T brucei or products of its infection may compromise cellular signaling in the brain and may trigger upregulation of immunomodulators such as neuroleukin. These results may have implications in the pathology of African sleeping sickness as well as prospects for treatment interventions.
COMPARISON OF EXPRESSION OF BASAL KERATIN K14 AND EPITHELIAL SPECIFIC ANTIGEN IN HUMAN SKIN, Nisha R. Patel [*], Karenne Fru and Wanda T Schroeder, Wesleyan College, Macon, GA 31210. Epithelial specific antigen (ESA) is used as a marker for epithelial carcinomas. Previous studies confirmed that ESA protein is also expressed in a number of different normal epithelial tissues; however, there are no published reports of ESA expression in normal skin. To determine the expression of ESA protein in normal skin, we performed indirect immunofluorescence microscopy (IIF) with a monoclonal antibody, NCL-ESA, specific for the ESA protein on frozen sections of normal human skin. In addition, to demonstrate whether the expression of ESA was differentially regulated, human skin sections were also incubated with a second antibody for human keratin 14, which is only expressed in basal, undifferentiated skin layers. Comparison of staining patterns with NCL-ESA and anti-K14 demonstrated that while expression of K14 is found on ly in basal keratinocytes, ESA protein is expressed throughout all layers of human epidermal tissue. Therefore, unlike several other epidermal proteins, including keratin, cornifin, and epidermal transglutaminase, ESA cannot be used as a differentiation marker in normal human epidermis.
THE EFFECT OF GENETIC BACKGROUND ON OFFSPRING SURVIVAL IN THE [SP.sup.4H] MOUSE, Esther Lee [*], Supriya Reddy, Nisha Patel and Holly Boettger-Tong, Wesleyan College, Macon, GA 31210. [Sp.sup.4H] is a semi-dominant mutation caused by a deletion of approximately 1.53[plus or minus]0.6cM on mouse Chromosome One. This deletion was caused by low dose radiation exposure of a hybrid C3H/HeH X 101/HeH [F.sub.1] male mouse. When [Sp.sup.4H] heterozygote mice were mated, a decrease in the predicted number of homozygote pups was observed. One of the genes deleted in [Sp.sup.4H] animals is Pax3. To determine if genetic background of the Pax3 locus has an effect on [Sp.sup.4H] embryo survival, the following experiment will be performed. Eight pairs of mating animals four Sp/B6 X Sp/B6 (parents bearing a B6 allele at Pax-3) and four Sp/C X Sp/C (parents bearing a Ch3H allele at Pax3) will be identified. Verification of the locus genotype will be achieved by PCR, with primers (241VB9) spanning a region of Pax3 containing a C3H/B6 polymorphism. After verifying the locus genotype and performing the appropriate matings, we will determine if there is any significant difference between the C3H and B6 Pax3 locus in the survival of [Sp.sup.4H] pups.
INVESTIGATION INTO THE FATE OF HOMOZYGOUS MUTANT [Sp.sup.4H] EMBRYOS 5.5 AND 6.5 DAYS AFTER FERTILIZATION, Toyosi Fatunase [*] and Holly Boettger-Tong, Wesleyan College, Macon, GA 31210. The [Sp.sup.4H] mouse has a deletion which includes the Pax3 gene region of mouse chromosome 1, resulting in a white belly patch in the heterozygote condition. In the homozygote condition, this results in early embryonic death. This research project seeks to identify the developmental stage at which death occurs since it is known that there are no homozygotes present in the uterus by day 7 post coitus. To achieve this goal, embryos from the mating of four pairs of [SP.sup.4H] mice will be dissected out of the maternal decidua using microsurgical techniques. Each embryo will be genotyped by Polymerase Chain Reaction analysis 5.5 and 6.5 days after fertilisation has occurred, using primers specific for Pax3. If no homozygote embryos are observed at either of these two time periods, PCR analysis of blastocysts will be undertaken .
ALCOHOL INHIBITS WOUND HEALING IN GINGIVAL FIBROBLASTS, Lisa M. [Sheehan.sup.1] [*], Augustine H. [Chuang.sup.2] and Claudia L. [Henemyre.sup.2], [Augusta.sup.1] State University, Augusta, GA 30901 and [Clinical.sup.2] Investigation, Eisenhower Army Medical Center, Ft. Gordon, GA 30905. Alcohol has been associated with a decrease in wound healing. This project was conducted in order to determine the effects of alcohol on wound healing in human gingival fibroblasts. A 3mm wound was created in a synchronized, confluent layer of gingival fibroblasts grown in 12 well plates. The wounded areas were then treated with 0% (control), 2%, and 4% solutions of alcohol in DMEM media with 10% FBS. At six days in culture, the wells were stained .with two different cytoplasmic stains, crystal violet and light green, to evaluate wound healing. In the wells with higher levels of alcohol present, overall cell detachment in the non-wound areas was visible. Fewer cells repopulated the wound as compared to the control (with no alcohol present) cells. Alcohol treated cells appeared distorted in shape and had less cell area. In conclusion, increasing levels of alcohol lead to an increase in cell detachment and distortion, and a decrease in repopulation and cell area.
NICOTINE STIMULATES DIFFERENTIATION AND ACTIVITY OF CULTURED PORCINE OSTEOCLASTS, Candice D. [Anderson.sup.1] [*], Augustine H. [Chuang.sup.2], Donald K. [Scales.sup.3] and Claudia L. [Henemyre.sup.2], [Paine.sup.1] College, Augusta, GA 30901, [Clinical.sup.2] Investigation, Eisenhower Army Medical Center, Ft. Gordon, GA 30905 and [U.S..sup.3] Army Peridontal Residency, Ft. Gordon, GA 30905. Clinical evidence of bone degeneration has been associated with tobacco smoking in both humans and in animal models. Nicotine is one of the major components associated with tobacco smoke. This project was conducted in order to determine the effects of nicotine on osteoclasts, the bone resorbing cells that are important in normal remodeling. Marrow cultures containing osteoclasts were harvested from porcine long bones and cultured on calcium phosphate thin films. Cells received 0, 5, 25, 50, 100, or 250 ng/ml nicotine. As the concentration of nicotine increased, so did the number of mature osteoclasts (i.e. tartrate-resistant acid phophatase positive cells with 3 or more nuclei). From 0 to 50 ng/ml nicotine, there was also a significant increase in resorption. In conclusion, nicotine increased differentiation and activity of osteoclasts.
PORCINE MARROW BUT NOT BUFFY COAT CELLS RESORB BONE AND CALCIUM PHOSPHATE THIN FILMS, Augustine H. Chuang. Phyllis D. Brewer, Royce R. Runner, James C. McPherson and Claudia L. Henemyre, Clinical Investigation, Eisenhower Army Medical Center, Ft. Gordon, GA 30905. Perturbations of osteoblasts and osteoclasts can lead to crippling diseases such as osteoporosis. In this study, we evaluated the use of a porcine marrow culture to study osteoclast biology. Marrow was harvested from long bones and the huffy coat from whole blood. The marrow contained osteoclasts while the buffy coat served as a control for other possible hematopoietic resorbing cells. Marrow cultures stained for tartrate-resistant acid phosphatase, a marker for osteoclasts, while buffy coat cells did not. Cultures were then evaluated for their ability to resorb bone or a calcium phosphate thin film. Scanning electron microscopy was performed on bone slices and calcium phosphate thin films cultured with no cells, marrow cells, or buffy coat cells. A reas of resorbed bone and calcium phosphate were detected in samples cultured with marrow cells only. Therefore, porcine marrow cultures are a useful model to study osteoclast resorptive activity.
COMPARISON OF THE SOLUBILITY IN A SURFACTANT SOLUTION OF TWO AROMATIC ACIDS THAT HAVE MEDICINAL USES, Richard M. Graven, B.J. Hughes and James C. McPherson, Jr., Department of Emergency Medicine, Medical College of Georgia, Augusta, GA 30912. Both salicylic acid and acetylsalicylic acid (ASA) are useful medicinal agents. These acids exhibit limited water solubility, which lessens their usefulness for IV administration. In this study we have measured the solubility of these acids in water and in a poloxamer 188 sol. Materials: Distilled water, a 12mM/L solution of poloxamer 188, solid salicylic acid, ASA, standardized Ba [(OH).sub.2] solution. Method: An excess of each acid was suspended in water as well as in the poloxamer 188 solution and stirred for 48 hours at room temperature. The suspensions were filtered, the filtrate weighed and titrated with the Ba [(OH).sub.2] solution. The solubility was calculated as mg/100gm solution for comparison. Results: The solubility in water was 232[+ or -]3m/100gm for sali cylic acid compared to 428[+ or -]28mg/100gm for ASA, indicating the solubility of aspirin in greater than its unesterified acid. The solubility in the poloxamer solution was 1140[+ or -]48mg/100gm salicylic acid compared to 688[+ or -]44mg/100 gm for ASA. Conclusion: An increased concentration of these acids can be achieved by dissolving in poloxamer solution.
Section VI: Philosophy and History of Science and Section VIII: Anthropology
Room SB 262
John E. Moore, Presiding
9:00 THE DEMOCRATIC GROWTH AND CHANGE OF THE ELDERLY IN GEORGIA, 1990-1998, Qingfang Wang, University of Georgia, Athens, GA 30605. Aging trend is rapidly becoming one of the most distinct features of modernity, including USA. However, the changing pattern of the elderly in Georgia is quite different from the whole nation. By using data from US Census 1990-1998, this paper outlines the pattern at a state level. The percentage of the elderly in Georgia have been declining during the period under study. The declining is due to economic growth and local development, which as been drawing many non-elderly (job-oriented) labor force outside. However, at the county level, compared with 1990, the spatial distribution of the aged population in 1998 seeming shows a "metropolitan revival." Particularly, the elderly are no longer the cohort stagnant and left by the young in an unfavorable condition. The impacts of elderly migration and redistribution become manifest in demand for shelter, health care and community services.
9:30 ANDRE MICHAUX AND MAGNOLIA CORDATA, Charlie [Williams.sup.1] and George A. [Rogers.sup.2], [Public.sup.1] Library of Charlotte and Mecklenburg County, Charlotte, NC 28202 and [Georgia.sup.2] Southern University, Statesboro, GA 30458. Primary and secondary sources were examined, including the Herbarium Michaux at the Laboratorie de Phanerogamie in Paris, to investigate the question whether the binomial Magnolia cordata in Michaux's Flora Boreali-Americana (1803) is in fact the same taxon as the binomial Magnolia cordata used in Michaux's journals and shipping documents. The evidence suggests that three different taxons are indicated depending upon where in the writings of Michaux the binomial Magnolia cordata is found.
10:00 NATURAL PHILOSOPHY REFORMED BY DIVINE LIGHT, Emerson Thomas McMullen, Georgia Southern University, Statesboro, GA 30460. Partly because of the Reformation, in the late Renaissance, Aristotellianism came under heavy criticism. One result was that new natural philosophies started to appear. These included Epicureanism, Stoicism, varieties of neo-Platonism, and more. There was also a reexamination of the Bible that generated a new literalism. Several thinkers complained that the Bible's meaning had been distorted to fit pagan natural philosophy, especially Aristotelianism. They called for, in Johann Amos Comenius' words, a "natural philosophy reformed by divine light" that is, one based on Biblical principles. The new Biblical literalism variously affected the thinking of the giants of the Scientific Revolution: William Harvey, Rene Descartes, Robert Boyle, Johannes Kepler, Isaac Newton, and others.
10:30 Business Meeting
10:45 Coffee Break
11:00 A COMMENTARY ON A RARE SMITHSONIAN PUBLICATION ON NORTH AMERICAN PITCHER PLANTS, Vivian [Rogers-Price.sup.1], George A. [Rogers.sup.2] and Daniel V. [Hagan.sup.2], [The.sup.1] Mighty Eighth Air Force Heritage Museum, Pooler, GA 31322 and [Georgia.sup.2] Southern University, Statesboro, GA 30460. This seldom seen 1935 publication includes "Illustrations of North American Pitcherplants" by Mary Vaux Walcott, "Descriptions and Notes on Distribution" by Edgar T. Wherry and "Notes on Insect Associates" by Frank Morton Jones. Fifteen colored paintings by Walcott are shown in meticulous detail. Wherry discussed the geographic dispersion of pitcher plants from an ancestral origin (eastern Tennessee and western North Carolina) accompanied with distribution maps. Jones describes the behaviors of the insects associated with the pitcher plants with much detail.
11:30 WAS THE AUTHOR OF "GEOLOGY," PUBLISHED IN 1830 IN THE SOUTHERN REVIEW, STEPHEN ELLIOTT, Sr., STEPHEN ELLIOTT, Jr., THOMAS COOPER OR JAMES HAMILTON COUPER? George A. [Rogers.sup.1] and Vivian [Rogers-Price.sup.2], [Georgia.sup.1] Southern University], Statesboro, GA 30460 and [The.sup.2] Mighty Eighth Air Force Heritage Museum, Pooler, GA 31322. Stephen Elliott Sr. launched The Southern Review in 1828 for family reasons and as evidence of southern intellectual achievements. The essay "Geology" was published after his death, during his son's editorship. Although the essays were unsigned, many attributed "Geology" to Dr. Thomas Cooper of South Carolina College. James Hamilton Couper, an amateur paleontologist and a planter in Glynn County, Georgia whose plantation was on the south bank of the Altamaha River, has been suggested as the author. Internal evidence corroborated by other factors suggest that the author was Stephen Elliott Sr. and that it was published posthumously.
Section VII: Science Education
Room AB 105
Steven McCullagh, Presiding
8:15 LINKING STUDENT SCHOLARSHIP TO TEACHING NEEDS, Michelle D. Hall [*] and Dale L. Vogelien, Kennesaw State University, Kennesaw, GA 30144. Many faculty search for new ways to engage and mentor students in scholarship. This paper describes a case in which student scholarship produced a new laboratory exercise for a senior level course. The role of plant hormones in growth and development is a major topic in plant physiology courses. While acceptable laboratory exercises are plentiful for some topics, most available laboratory exercises dealing with plant hormones are observational, dated in methodology, or require equipment and/or facilities that may not be available. A senior level student developed a laboratory exercise that allowed plant physiology students to study the involvement of abscisic acid (a plant hormone) in a plant's detection and response to soil water deficit. The student adopted an experimental setup, but modified the original study to use the newest method of hormone analysis - the immun oassay. The resulting exercise is a relevant and exciting experiment that is adjusted to meet time and equipment restraints. Benefits to instructor, investigating student, and a plant physiology class that piloted the exercise will be presented. Formal and informal class assessment data on the new exercise will be shared.
8:30 GENERATING MEANINGFUL ENVIRONMENTAL DATA SETS IN AN INTRODUCTORY SCIENCE CLASS, Joseph M. Dirnberger, Kennesaw State University, Kennesaw, GA 30144. Because turbidity in streams in greatly affected by runoff from rain, it is difficult to characterize turbidity over a large region from samples taken over many dates. This project takes advantage of large class size in an introductory science course to compare turbidity in creeks over NW Georgia on a single date. Each student collected a sample from an area stream for turbidity analysis and documented surrounding land use. Turbidity was highest within suburban Atlanta. Using this data set, students developed creative analyses to identify potential sources. Students were then trained to assess effectiveness and compliance of erosion control practices. Students prepared position statements using evidence from both data sets to argue for or against the need for additional protection in area streams. Not only did this exercise introduce students to the complex ity of environmental data sets and to the difficulty in using such data to affect policy, but it also generated a unique and potentially useful snap shot of turbidity.
8:45 "I BIO," A MIDDLE SCHOOL HUMAN BIOLOGY AND NUTRITION CURRICULUM THAT INCORPORATES BIOMEDICAL ENGINEERING RELATED MATERIAL, Aaron James, Mercer University, Macon, GA 31207. In the summer of 2000 the author, a student at Mercer University, participated in a REU program at Northwestern University that was working to develop a curriculum entitled "I BIO" that exposes foundational biomedical engineering material to Chicago area middle students. The main purpose in this curriculum is to have students redesign their school lunch based on their energy needs with information they collect using an in-house made indirect calorimetry system [IHICS] (this system measures energy expenditures from the body). The author first calibrated a Vernier oxygen-sensor and adjusted the settings of a DataStudio [R]?? computer program to use with the oxygen sensor (this was done for use in the IHICS). The author then used the raw data from the IHICS to calculate the amount of energy expended from the body by using physiological e quations. The curriculum has not yet been piloted so the effectiveness of it cannot be assessed. the IHICS has been tested twice and yielded less than 10% error as compared to references.
9:00 BALDWIN HIGH SCHOOL/GEORGIA COLLEGE & STATE UNIVERSITY SCIENCE INITIATIVE, Elizabeth L. Bennett and Cathy Grimes, Georgia College & State University, Milledgeville, GA 31061. The Baldwin High School (BHS)/Georgia College & State University (GC&SU) Initiative was implemented in January 2000. The purposes of this initiative are to align the curricula, strengthen ties between high school and college faculty, give high school students a more realistic view of college expectations, and expose college students to the idea of teaching at the secondary level. Over the course of this collaboration, a course and pacing guide, which reflects alignment of the curriculum, was produced. In the fall, an end-of-course exam for the 10th grade biology classes was compiled. Topics such as study skills, time management, course difficulty, choosing a major, and sample 4-year course sequences for various majors were discussed with these classes giving students a more realistic view of what to expect in college. Several GC&SU biology majors visited BHS over the course of both semesters to observe the science classes. This has resulted in one of these students deciding to enter the M.A.T. program at GC&SU after finishing her B.S. degree in biology.
9:15 INSIGHTS INTO ORGANIZING AND RUNNING A COMMUNITY OUTREACH PROGRAM, Catherine E. McGowan [*] and Donna Mullenax, Department of Chemistry, Physics and Engineering Studies, Armstrong Atlantic University, Savannah, Georgia 31419. Universities and Colleges have always recognized the need to work closely with their surrounding communities. One of the missions of Armstrong Atlantic State University (AASU) is working with local K-12 educational institutes (private and public) to enhance the educational opportunities for both students and instructors. The Chemistry & Physics Department community outreach program was developed and implemented to meet this objective. Each academic year, letters are sent out inviting area middle school and high school classes to come to our campus to perform chemistry and/or physics experiments in our laboratory classrooms. Early middle school classes are invited to visit our campus for a "Fun with Science" demonstration show. This presentation will discuss the lessons learned and t he mechanics of putting together a successful outreach program.
9:30 REMEMBERED BIOLOGICAL CONCEPTS AND PERCEPTIONS: A COMPARISON BETWEEN GEORGIA AND NON-GEORGIA HIGH SCHOOL GRADUATE NON-SCIENCE MAJORS, Don Davis, Pam Rhyne and Gail Schiffer Kennesaw State University, Kennesaw, GA 30144. This study investigates the biological concepts and perceptions that students in their first non-science major course remember from their high school biology experiences. Data were collected from 327 Georgia students and 135 non-Georgia students. There were no significant differences between Georgia and non-Georgia students in grades received, favorite high school biology experiences, or correlation of grade received and continued interest in biology. There were significant differences in ages, with the majority of Georgia students graduating from high school in the 1990's and more non-Georgia students graduating in the 1970's. Significantly more non-Georgia than Georgia students reported hands-on activities and dissection to be their least favorite experience. Comparison of the first wor k remembered about biology shows significantly more non-Georgia students recalling dissection and frogs and significantly more Georgia students recalling anatomy and labs. Significantly more Georgia students remembered genetics and ecology as important biology ideas while significantly more non-Georgia students recalled ideas about plants and animals. In all categories from both groups "don't remember" was the most frequent response.
9:45 MODELS COMPARED WITH DISSECTION FOR TEACHING ANATOMY, Lynelle Golden, Pam Rhyne and Janet Robison, Kennesaw State University, Kennesaw, GA 30144. Undergraduate anatomy labs are often taught using models instead of dissection. The study objective was to determine if students taught anatomy with plastic models are able to identify structures on dissected specimens. Anatomy and physiology lab students were divided into three groups and taught heart anatomy using dissection (D), models (M) or a combination of dissection and models (DM). Results were assessed using a practical lab exam and student surveys. The mean ([+ or -]SD) exam scores were D: 62%[+ or -]23, M: 67%[+ or -]21 and DM: 63%[+ or -]21. Scores were not significantly different and suggested that use of plastic models was not an important determinant of a student's ability to identify heart structures. Survey results indicated that students did most of their studying outside of lab using textbooks. Therefore, low exam scores may reflect insuffici ent time or focus on learning structures using materials in lab. These results suggest that if the objective of undergraduate anatomy labs is for students to learn to identify structures on real specimens, then more emphasis should be placed on dissections during lab.
10:00 Business Meeting
10:30 IN SEARCH OF RELEVANCY, Kailash Chandra, Savannah State University, Savannah, GA 31404. In most physics courses, students are not exposed to an application of physics in day-to-day lives. Students who are required to take physics generally ask the question "Why do we have to take physics?" Problem-Based Learning has been successfully used at Savannah State University to answer such questions. PBL is an approach to learning in which problems serve as the stimulus for students to gain course concept and content. PBL problems are open-ended, based on real situations and have more than one "right" answer. A PBL problem successfully used at Savannah State University during Fall 2000 semester will be presented. This activity has enhanced the interest of students in learning Physics.
10:45 PDF FILES: A COLLEGE PROFESSOR'S BEST FRIEND, Matthew M. Laposata, Kennesaw State University, Kennesaw, GA 30144. The web is commonly utilized in college courses, but problems invariably arise when documents other than web pages are considered. Distributing handouts, PowerPoint presentations, and articles to your students through the web is complicated by that fact that your students' computers may have operating systems and software applications that do not allow them to view your course materials. By using Adobe Portable Document Files (PDF), this concern is a thing of the past, as documents in this format can be viewed on any computer regardless of operating system or software. Most instructors regularly view PDF documents on the web, but are unaware that creating their own PDF files is easy and affordable. In this talk I'll demonstrate several practical uses for PDF files in college science courses, and describe how to obtain the applications for writing and reading PDF files. Whether a novice or e xpert with technology, you'll come away from this presentation with several uses for PDF files in your course, and the resources to put those ideas into action.
11:00 WEBCT[TM] COURSEWARE FROM A TEXT BOOK PUBLISHER: RESULTS EXPERIENCED BY AN ON-LINE TEACHING NEOPHYTE, Allan A. Gahr, Gordon College, Barnesville, GA 30204. Placing a science course online using WebCT[TM] is a formidable task. Several text book publishers supply WebCT[TM] courseware either 'free' upon adoption of their text or at a nominal charge. Such courseware was used to teach a two credit-hour course introducing students to the field of environmental science. This is a report on the course design, implementation, mid-course corrections, and student learning results. Preliminary analysis of the on-line teaching assessments points to a deficiency in student metacognitive skills.
Section IX: Genetics Society of Georgia
Room AB 103
Kathleen Ann Fleiszar, Presiding
9:15 PHYSICAL AND BIOLOGICAL FACTORS CONTROLLING PARTICLE BOMBARDMENT MEDIATED DNA TRANSFER TO SPARTINA ALTERNIFLORA TISSUES, A.G. Harkins [*], W.H. Palefsky and C.I. Franklin, Department of Biology, Savannah State University, Savannah, GA 31410. The smooth cordgrass (Spartina alterniflora) is a dominant plant species in salt marshes of southeastern United States. A gene transfer system via particle bombardment mediated DNA transfer is being developed for this species in order to apply the transgenic technology to produce genetically engineered S. alterniflora that can be used as biosensor for heavy metal contamination in salt marshes. The efficiency of DNA delivery was measured based on transient expression of the [beta]-glucuronidase reporter gene. Parameters such as helium pressure, distance between the stopping plate and the target tissue in the particle delivery system, plasmid concentration, and different explant types were tested. Results from this study indicate that a plasmid concentration of 1.5 [m icro]g/delivery, 85 mm of particle travel distance, 1550 psi of helium pressure and 18 inches of mercury vacuum are optimal for efficient DNA delivery via particle bombardment to S. alterniflora explants isolated from surface-sterilized fleshy young shoots.
9:30 DISRUPTION OF THE LIGHT/DARK CYCLE IN DROSOPHILA MELANOGASTER ALTERS THE NUMBER OF OFFSPRING PRODUCED AND LARVAE MIGRATION: A GENETIC IMPLICATION, Seth A.R. Adkison [*], Kerry L. Coburn and Linda R. Adkison, Mercer University School of Medicine, Macon, GA 31207. Wild type (WT) and eyeless (ey) D. melanogaster mutants were exposed to a constantly strobing light to disrupt their circadian rhythm. An environmental chamber was designed which allowed light exposure to the parentals only or larvae only. Controls were maintained in a 12 hr light/dad cycle. Offspring were counted for 10 days. At the end of 10 days a "migram" was constructed in order to measure how far the larvae migrated before becoming pupae. In all experiments, WT and ey produced fewer offspring in the experimental groups with one exception. In the ey experiments in which only the parentals were exposed to the strobe light, significantly more offspring were produced. This was not the result of egg laying differences. In WT experiments, disrup tion of the circadian rhythm cause a decrease in migration. In ey experiments, there was an increase in migration unless both parentals and larvae were exposed to the strobe light. New experiments were designed to study these variables in F1 offspring of the crosses WT x ey and ey x WT. Preliminary data suggests that the Pax-6 gene (ey) may be involved in ovary development and larvae migration.
10:00 Business Meeting
10:30 ANALYSIS OF CHLOROPHYLL LEVELS IN TRANSGENIC AND MUTANT PROLIFEROUS LINES OF ARABIDOPSIS THALIANA IN RESPONSE TO VARYING AMOUNTS OF THE SYNTHETIC CYTOKININ KINETIN, Natalie M. Moss [*], Shelly Ann Foster, John Chipley and Linda Hensel, Mercer University, Macon, GA 31207. We have isolated lines of Arabidopsis thaliana that cease to undergo wild-type meristem arrest resulting in nearly two-fold fruit production. We have found that the plf lines show a substantial and consistent difference from wild-type plants in their response to kinetin. These results have led to a modified model of regulation of meristem proliferation. We are now determining if the kinetin-response assay will be useful as a pheotypic marker. Currently, phenotypes of the second filial generation are determined by fruit production. It takes an extended amount of time to observe the phenotype of the plants. By improving upon our current method of determining phenotypic identify, we hope to efficiently map the plf gene.
(*.) (Denotes Student Presentation)