Abstracts of papers presented at the 1999 annual meeting of the Louisiana Academy of Sciences.
Northeast Louisiana University Monroe, Louisiana 4-5 February 1999 The following abstracts of paper and poster presentations represent those received by the Editor. Authors' affiliations are abbreviated as follows: CC Centenary College GSU Grambling State University LAES-C Louisiana Agricultural Experiment Station, Calhoun LAES-H Louisiana Agricultural Experiment Station, Hill Farm LDWF Louisiana Department of Wildlife and Fisheries LSU-BR Louisiana State University, Baton Rouge LSU-E Louisiana State University at Eunice LSUAC-BR Louisiana State University Agricultural Center, Baton Rouge LSUMC Louisiana State University Medical Center, New Orleans LSUMS-UMCL Louisiana State University Medical College in Lafayette LSU-S Louisiana State University in Shreveport LTU Louisiana Tech University LU Loyola University, New Orleans McSU McNeese State University NiSU Nicholls State University NLU Northeast Louisiana University NSU Northwestern State University SLU Southeastern Louisiana University SU-BR Southern University at Baton Rouge SU-NO Southern University at New Orleans TuMC Tulane Medical Center UNO University of New Orleans USGS-BRD U.S. Geological Survey--Biological Resources Division USL University of Southwestern Louisiana XU Xavier University
AGRICULTURE, FORESTRY, AND WILDLIFE DIVISION
Ardoin, A.M. and V.L. Wright. LSU. Effects of box spacing and litter on wood duck (Aix sponsa) nest box use in different regions of Louisiana.--One-hundred forty-four nest boxes on 7 federal wildlife reserves were examined monthly. Boxes were arranged in two spacing treatments (>100 yds or <50 yds), and three litter types (shavings, chips, and sawdust). Utilization of boxes filled with shavings was higher than that of boxes filled with sawdust or chips. Nest success was not equal on all areas. Hatch rate was not related to area, spacing, or litter. Dump nesting did not significantly reduce hatch rate until clutch size exceeded 25 eggs. Boxes with successful nests were more likely to be reused. Hooded mergansers (Lophodytes cucullatus) were the most frequently encountered nest competitor, and were concentrated on Lake Ophelia NWR. Success rate of mixed clutches (hooded merganser-wood duck) and pure wood duck clutches were not different.
Borsari, B. LSUE. Teaching agriculture in tropical Africa: Understanding the local culture for the design of a sustainable curriculum.--For several decades western agriculturists have been working in African countries to impart knowledge in a teaching capacity. This educational effort has been carried out, since then, to increase agricultural productivity and to improve the living conditions of the local populations. The final outcome of many of these development projects has not had the expected impact, although funding, equipment and human resources were readily available. As it was demonstrated later on, the knowledge transfer had taken place without understanding the real needs of the project recipients. This omission seems to have occurred also because of lack of knowledge of the local culture. This paper will discuss how important is the knowledge of a culture, for the design of an effective agricultural curriculum, especially when the educator is working in a foreign environment.
Busby, T. and K.S. McLean. NLU. G.W. Lawrence. McSU. Fungicide seed treatments for management of cotton seedling disease in Louisiana.--A cotton seedling disease seed treatment fungicide test was conducted on the Northeast Louisiana University Johnson Farm to determine the benefits of selected fungicides on cotton seedling disease. Seed treatments consisted of varying rates of Apron XL, Maximum, Nu-Flow M, Nu-Flow T, RTU Bayton/ Thiram, WE 120C, CF Clear, and an untreated control. All fungicides were applied to Stoneville 474 seeds before planting. At 14 days after planting seedling stand ranged from 178 to 140 plants per 40 feet of row for WE 120C+Nu-Flow M+Apron XL+CF Clear combination treatment and the control, respectively. By 21 days after planting, the stand in all the seed fungicide treatments were significantly greater than the stand in the control treatment. At 28 and 42 days after planting, five of the seed fungicide treatment combinations produced cotton stands which were significantly greater in number than the control. Plant height measured at 42 days after planting indicated no differences in plant height between any treatments. Seed cotton yield ranged from 2,439 to 1,784 lb/acre for Nu-Flow T+Nu-Flow M+Apron XL + CF Clear combination treatment and the control, respectively. The average yield for all seed fungicide treatments was 2,188 lb/acre, indicating a 404 lb increase in yield over the control.
Calloway, E., D. Collins, and B. Borsari. LSUE. I. Koemer. Imparting the effectiveness of sustainable agriculture extension courses through interactive distance learning technology.--Distance learning technology is an efficient communication modality that is quickly revolutionizing education. Colleges of Agriculture are very receptive to this issue because through distance education technology knowledge can be easily imparted to remote, rural areas. The potential of reaching a broader spectrum of farmers and operators working in the field is truly remarkable, especially for the delivery of updated, technical information that aim at developing more sustainable farming practices. The efficacy of distance learning, however, is possible only if stakeholders become cognizant that the recipients of the instructional effort are primarily self-directed learners. This paper will demonstrate that the consideration of this educational concept (self-direction) is necessary in order to achieve maximum results in sustainable agriculture courses, if these are taught through this innovative, teaching modality.
Deckard, D. and D. McCurdy. LTU. Industrial consumer response to sawtimber scarcity.--This study proposes a framework of rational economic decision making to facilitate understanding of industrial consumer behavior when faced with rising real prices for low grade sawn wood products. A posttest-only control group field experiment was conducted, presenting real price increase scenarios to key decision makers in the domestic railroad industry. Principal Components Analysis (PrC) was used to test the four factor model: 1) product life-cycle extension, 2) improvements in procedural efficiencies, 3) product substitution, and 4) innovation. The factor model explained 68 percent of the total variance in materials supply strategy. Overall, intended supply strategy was identified as a serious threat to hardwood crosstie market share at real price increase levels greater than 1.5 percent per year.
Gels, K.D., W.H. Green, M.W. Murphey, S.S. Kosechata, T.F. Loftin, and K.D. Hollis. LTU. Efficacy of low doses of oxytocin and dinoprost tromethamine in the induction of parturition in mares.--The objective was to determine if an oxytocin and dinoprost tromethamine combination was a safe, reliable method for induction of parturition in mares when criteria for foal readiness were met. Mares received 20 IU oxytocin i.m., 1.25 mg dinoprost tromethamine i.m. and 7.5 IU oxytocin i.v. with 7.5 IU oxytocin i.v. administered every fifteen minutes until stage two parturition. Stages one, two, and three of parturition were 17.14 [+ or -] 3.99, 10.79 [+ or -] 1.87, and 31.64 [+ or -] 8.94 minutes, respectively. Foals stood and nursed in 23.50 [+ or -] 1.91 and 39.14 [+ or -] 4.18 minutes. The pharmaceutical combination was a safe, predictable method for induction of parturition.
Giordano, M.R. LSU-BR. and R.M. Pace, III. USGS-BRD. Comparative morphometrics of coyote-like canids in southwest Louisiana.--Canid taxonomy in southeast Texas and southwest Louisiana is uncertain due to hybridizations among red wolves (RW, Canis rufus), coyotes (COY, C. latrans) and domestic dogs (C. familiaris). We compared body measurements of coyote-like animals (SC) from Sabine National Wildlife Refuge to prior measurements of RW, COY, dog hybrids (DH) and coyote-like canids (CLC) from across Louisiana and southeast Texas. Multivariate comparisons showed that SC captured during 1995-1996 were similar in mass, total body length and shoulder height to DH measured during 1974-1980. SC were significantly larger than COY and smaller than RW from the same study. SC were significantly larger than COY and CLC measured in two other Louisiana studies. Differences among food resources may explain why SC are larger than COY and CLC, but inheritance of RW traits could be a factor. Morphometric differences demonstrate the need for genetic studies to clarify the taxonomic status of CLC in Louisiana.
Green, W.H., G.A. Kennedy, and M.W. Murphey. LTU. Geographic and economic impacts of equine infectious anemia on the Louisiana Agricultural Industry.--Equine Infectious Anemia (ETA) is a contagious viral disease of horses that has no effective treatment or vaccine. Prevention or control of the disease is by testing, quarantine, and destruction of infected animals. Louisiana has historically reported a high incidence of infected animals. This poster illustrates the geographic incidence and estimates the economic impact of EIA on the Louisiana agricultural industry. Results indicate a high incidence of the disease along the coastal regions of the state and an estimated economic loss of more than $5.6 million in animal value and related value added between January 1995 and June 1998.
Loftin III, T.F., K.D. Geis, A.R. Williams, and D.J. Beebe. LTU. Micro-chip attachment to bovine oocytes through microencapsulation.--A 2% sodium alginate (SA) solution was used to attach polysilicon micro-chips to bovine oocytes for individual identification. Three separate trials, 60 individually encapsulated oocytes with a micro-chip inclusion per trial, were used to examine the effects of micromanipulation (MME), simulated IVC (CME), and cryopreservation (FME). Firmness of micro-chip attachment and the integrity of the SA capsule were examined each time. Results show that a high percentage of oocytes persisted in chip attachment by encapsulation through all three trials: (FME)=85%, (MME)=100%, (CME)=100%. The results of this project indicate that bovine oocytes can be individually identified through micro-chip attachment via SA encapsulation.
Marsh, C. and K.S. McLean. NLU. G.W. Lawrence. McSU. H.B. Bounds and D. Brotherton. NLU. J. Barnet. LSU. Cotton runoff water quality as affected by best management practices in Louisiana.--A cotton best management production test was conducted by NLU in cooperation with LA DEQ, LSU and NRCS to determine the benefits of best management practices on runoff water quality. Treatments consisted of (1) conventional tillage, (2) conventional tillage+integrated pest management (IPM)+cover crop, (3) conservation tillage+IPM and (4) conservation tillage+IPM+cover crop+transgenic cotton. Runoff water samples were collected during five rain events spaced approximately four weeks apart during the growing season in 1997 and again in 1998. Ammonia nitrogen, nitrate nitrogen, phosphorus, total suspended solids, and pH concentrations in the runoff water were determined after each rain event. The amount of total suspended solids was greater in the conventional tillage compared to the conservational tillage treatments at all rain events over the two years. Variation in the amount of ammonia nitrogen, nitrate nitrogen, and phosphorus was observed between treatments. Seed cotton yield was greatest in the conservation tillage+IPM+cover crop+transgenic cotton compared to the other treatments.
McLean, K.S. NLU. G.W. Lawrence. McSU. R. Prince. Tri State. A plant parasitic nematode survey of the Ouachita Delta and Macon Ridge production areas of Louisiana.--Thirty-one producer fields were surveyed representing 10,780 acres of the Ouachita Delta and Macon Ridge areas of Louisiana. Plant parasitic nematodes were identified from cotton, soybean, and corn production areas. Ten genera of plant parasitic nematodes were identified, Four genera of importance in crop production, Rotylenchulus reniformis, Meloidogyne spp., Hoplolaimus spp. and Pratylenchus spp. were recovered at a frequency of 68%, 26%, 2.4% and 8.2%, respectively. The reniform nematode (Rotylenchulus reniformis)was identified in 68% of the samples, which represented 7,330 acres. Root-knot nematode (Meloidogyne spp.) was identified in 26% of the samples, which represented 2,803 acres.
Reagan, S., J. Ertel, and V. Wright. LSU. Use of passive identification tags for identifying American alligators.--Cranial mounted reflector pads and Passive Integrated Tags (PITs) were evaluated over a 16-month period as identifiers of individual Alligator mississippiensis. Reflectors were attached by screws to the squamosal bones of 18 adult alligators. Dental acrylic molds were created around the skull cap at the periphery of the squamosal bones to prevent necrosis of skin. Alligators were visually recognizable to a distance of 10 m; submerged the range dropped to 0.5 m. PITs were manually injected into the right ear flap of 278 adult alligators. PITs were readable when within 10 cm of the reader's antenna. A extendable probe style antenna allowed identification of surfaced, denned, and submerged alligators. Five of 18 alligators with reflector pads were recaptured and no evidence of the system remained; the subsequent 95% confidence interval estimate of retention rate was 0 to 45%. Fifty-six of 278 alligators with PITs were recaptured and 5 PITs were missing and 3 were damaged. The 95% confidence interval estimate of retention of PITs was 77 to 99%.
Samkutty, P.J., R.H. Gough, and P. McGrew. LSUAC-BR. Utilization of a sequencing batch reactor system for the treatment of dairy plant wastewater.--The types of biological waste treatment methods utilized in the dairy industry are primarily activated sludge, trickling filters, aerated lagoons, irrigation, and a combination of these. The sequencing batch reactor (SBR) system is an activated sludge process which utilizes a mixed bacterial culture capable of effectively reducing biochemical oxygen demand (BOD), chemical oxygen demand (COD), and nutrients commonly found in wastewater. Wastewater enters the SBR to undergo biological treatment utilizing the principle of fill and draw. The process follows the basic steps of react, settle, decant, and wasting of sludge. This study demonstrated the successful utilization of the SBR system for the treatment of dairy plant wastewater as well as the applicability of COD as a rapid method for determining biological efficiency of the system.
BIOLOGICAL SCIENCES DIVISION
Allen, C.M. NLU. Analysis of selected woody vine populations in Louisiana.--Quantitative data for 28 species of woody vines collected from nine different sites in Louisiana were analyzed. The sites include forests dominated by hardwoods in the Boeuf Natural Area, Cunningham Brake Natural Area, a slope forest in Caldwell Parish, a pawpaw dominated forest near the Monroe Airport, a potential wetland area in the Killoden Plantation, and a bottomland forest in Darbonne National Refuge. The other three forests were pine hardwood forests and included one in the Darbonne National Refuge, the West Monroe Watershed Project, and the forested portion of the Keiffer Prairie Research Area. The three species with the highest importance value for the combined sites were poison ivy (Rhus radicans), rattan vine (Berchemia scandens), and muscadine (Vitis rotundifolia). The importance values for each species from each of the sites were correlated using the Pearson Coefficient. The three pairs of species that had the highest correlation were Vitis palmata--Brunnichia ovata, Trachelospermum difforme--Brunnichia ovata and Smilax hispida--Lonicera sempervirens. The vines in the Boeuf and Cunningham Brake Research Natural Area Forests had the highest correlation and those in the West Monroe Watershed Project and the bottomland forest in Darbonne National Refuge had the lowest correlation to other sites.
Allen, C.M. NLU. Proposed prairie restoration research on Lacassine Wildlife Refuge in Evangeline Parish, LA.--A research project to research methods for restoring prairie was established on the Lacassine Wildlife Refuge in Evangeline Parish, LA. Seeds and cuttings from native prairie plants were taken from remnant strips in southwestern Louisiana. The cuttings were tested for rootability and successful plantlets were potted for transplanting into the Duralde restoration site. Seeds were sorted and a sample tested for germination. The remaining seeds were stratified until the scheduled planting date. Seeds will be planted at the Duralde site during three time periods: November-December, January-February, and April-May. Prior to planting, a sample of the stratified seeds will be tested for germination. Conclusions are anticipated regarding use of cuttings and time of year to plant seeds plus effects of stratification on germination of seeds.
Allen, C.M. NLU. The flora and vegetation of Allen/Winters Nature Preserve.--Trails with labeled plants are being established on the 80 acre Allen/Winters Nature Preserve in Caldwell Parish near Columbia. Two hundred and eighty two species of vascular plants have been recorded for the area including 122 woody species of which 22 are vines. Additional species are anticipated with more explorations during the different seasons. The area contains five major vegetational zones including a small batture area along the banks of the Ouachita River, a natural levee strip, a fairly large bottomland hardwood forest, a hardwood slope forest along the bluff, and a large loblolly-hardwood forest. Additional vegetational zones are anticipated as the area is sampled quantitatively.
Reid C.S. and C.M. Allen. NLU. Methods for an ecological analysis of the vegetation of a Ouachita River floodplain forest in Caldwell Parish, LA.--Methods for the survey and analysis of the vegetation of a floodplain forest on the Ouachita River in Caldwell Parish will be discussed. The study area appears to be a variant of the overcup oak-water hickory forest type. Systematically-placed circular plots will be used to sample the vegetation, with nested plots of varying sizes to sample different plant life forms. Environmental variables such as elevation, soil texture, soil fertility, and flood duration will be determined and correlated to vegetation at each plot. This study appears to be different from other vegetation studies of this forest type in that this forest contains a conspicuous component of Forestiera acuminata throughout. Thus, a record of the vegetation of this area would be an addition to the knowledge of floodplain vegetation of Louisiana.
Vidrine, M.F., B. Borsari, J.E. Cordes, and M.S. McClendon. LSUE. C.M. Allen. NLU. Landscaping with native prairie in southwestern Louisiana: Part I. Cajun Prairie and the natural landscaping paradigm.--Remnants of prairie along railroad rights-of-way provide clues to the once highly diverse community native to southwestern Louisiana. All but approximately 100 acres of these remnants have been plowed or otherwise developed leaving only fragments of habitat. More than 500 plant species are known from remnants. In the central states, the paradigms for landscaping and perennial polyculture farming with native prairie plants are being implemented. These paradigms with modest modification provide an opportunity for the restoration of habitat and the development of an intensively beneficial habitat management potential.
Vidrine, M.F., B. Borsari, J.E. Cordes, and M.S. McClendon. LSUE. C.M. Allen. NLU. Landscaping with native prairie in southwestern Louisiana: Part II. The Cajun Prairie natural landscape models.--The primary model for landscaping is the remnant prairie. Secondary models include prairie restoration projects in Eunice and at LSUE. Tertiary models, where landscaping is being attempted, include the Cajun Prairie Gardens. These gardens are being developed on part of one suburban lot in a "washed-out" rice field that has been converted to three-acre suburban lots. These gardens are divided into roughly one-eighth acre demonstrations totaling approximately an acre and a half. Smaller prairie gardens in and around Eunice also serve as models. The development of a series of well-documented models provides for future expansion.
Vidrine, M.F., B. Borsari, J.E. Cordes, and M.S. McClendon. LSUE. C.M. Allen. NLU. Landscaping with native prairie in southwestern Louisiana: Part III. Benefits and problems with implementing the Cajun Prairie landscaping models.--Many benefits of natural landscaping with the Cajun Prairie models are the protection and creation of soil, the preservation of species and genetic biodiversity, pollinator and beneficial insect habitat creation, elevated property values, and enhancement of esthetic value. Problems with the models include antiquated weed laws, exotic weeds, potential pests, paucity in native seeds and plants propagules, and lack of expertise in local native prairie landscaping. Implementation of the models for natural landscaping with natives is proceeding in conjunction with the development of the models.
Environmental Science Section
Brown, J.T., J. Aucoin, G. Guzzetta, J.V. Chauvin, and G.V. Lo. Water quality assessment of Bayou Lafourche using a TI-CBL system.--A Texas Instrument Calculator Based Laboratory (TI-CBL) system was used to assess water quality parameters in Bayou Lafourche. Temperature, pH, conductivity, dissolved oxygen, and turbidity were monitored during a Louisiana Systemic Initiatives Program (LaSIP) summer institute for high school science teachers. National Sanitation Foundation water quality indices were determined and the overall water quality was found to be good. Poster presentation.
Clausen, R.D. and M.G. Heagler. McSU. Acute toxicity of the mosquito larvicide, Bacillus spaerieus, to the water flea, Daphnia magna.--Chemical insecticides have commonly been used to control mosquitoes, but due to insect resistance and toxicity to nontarget organisms, new solutions are being investigated. One potential alternative is to use microbial agents such as Bacillus spaericus (strain 2362). However, the toxicity of such agents should be investigated prior to their widespread use. Therefore, a toxicity test using Daphnia magna was conducted to determine the aquatic toxicity of Bacillus spaericus. Three replicates of five test concentrations (11. 1, 22.1, 44.1, 88.2 and 176.4 mg/L (nominal concentrations)) and a control were used. Bacillus spaericus was not toxic at these concentrations.
Goskonda, S., and T. Junk. NLU. W.J. Catallo. LSU. Ultrasonic treatment of refractory environmental pollutants.--The destruction of organic pollutants in aqueous solution with high intensity ultrasound constitutes a treatment method of increasing significance. Ultrasound-induced degradation rates were determined for a range of organochlorine and nitroaromatic substrates at varying concentrations. Results presented here will include a discussion of the structure-degradation rate relationship for selected substrates, the effects of environmentally benign cosolutes (surfactants, humic acids), the bulk phase pH and the temperature on the dechlorination rates of selected substrates. Evidence will be presented that metal power reduction resulting from sonicator horn erosion does not contribute to sonolytic degradation. Poster presentation.
Holt, B.J. and M.G. Heagler. McSU. Mercury concentrations in food.--Generally people consider the food purchased from their supermarket to be free from possible contamination, but this may not always be the case. The U.S. Food and Drug Administration (FDA) oversees the products found in our supermarkets. Researchers have measured mercury concentrations of raw fish tissue, and some types of fish, including swordfish (1. 19 mg Hg/kg [+ or -] 0.80), exceed the FDA's action level of 1.0 mg of mercury/kg of tissue. However, the handling and cooking of the fish prior to consumption may modify the mercury concentrations. Therefore, measurements were made to compare the mercury concentrations of fish before and after cooking. Data suggest that there is no statistically significant change in the mean concentrations between raw fish and cooked fish. In addition to these measurements, analyses were performed on foods other than fish. These data suggest that there are no unusually high concentrations in beef, chicken, or pork. Measurements will continue to be made along with variations in the cooking method. Poster presentation.
Howell, J.P., M.G. Heagler, M.G. McSU. Use of fertilizers as a means of controlling mercury uptake by plants.--Research is being conducted to determine the effects of fertilizer on the uptake of mercury by root vegetables (radish) and leafy vegetables (spinach). A soil's ability to adsorb mercury is determined by organic matter content. The soil's binding ability is a valuable physical barrier, but there is a risk mercury will be absorbed by resident plants. Commercial compost and inorganic fertilizers were incorporated into soil with an 8 mg/kg mercury concentration to examine the effect on uptake of mercury by plants. Mercury concentrations (mg/g) of both plants were examined. Comparisons were drawn between fertilizer treatments and mercury level per plant.
Kinard, D.W. and M.G. Heagler. McSU. Accumulation of lead in the marsh periwinkle snail, Littorina irrorata.--Lead concentrations have been measured in the marsh periwinkle snail (Littorina irrorata) collected from restoration sites in the Sabine National Wildlife Refuge. To determine the kinetics of lead accumulation in the snail, a sixty-four day exposure study was undertaken. Littorina were exposed to sediment contaminated with 0.5 mg/kg of lead and sampled on days 0, 2, 4, 8, 16, 32, 48, and 64. Lead concentrations were measured in the soft tissue as well as in the shell of the snail.
McNeill, A.C., J.B. Hill and S. Farrell. LTU. Identifying potential phytoremediators for crude oil contaminated soils.--Numerous, low volume crude oil spills occur on upland sites within the oil-producing regions of the southeastern United States. These spills can damage the environment through their toxic effect on the native vegetation. Phytoremediation involves the use of plants to reduce the level of contaminants in soil and groundwater and may be more cost-effective than conventional methods. A first step in using phytoremediation to restore oil-contaminated soil is to identify plants that can tolerate the presence of oil in soil. One approach was to collect native plants found growing within existing North Louisiana upland oil spill sites. In addition, potential phytoremediators were screened for oil tolerance under greenhouse conditions. Various plant species were grown in Sacul very fine sandy loam (clayey, mixed, thermic Aquic Hapludult) contaminated with North Louisiana sweet crude oil at concentrations ranging from 0 to 90 g oil per kg soil. Plant survival, biomass, and height were measured as indicators of each species' tolerance of oiled soil. Supported by OSRADP.
Schuler, L., J. Howell, and M.G. Heagler. McSU. Differences in mercury concentrations between Chinese and Louisiana crayfish.--This study examined and compared mercury concentrations of locally caught and processed crayfish to that of Chinese crayfish. Results indicate a significant difference ([alpha]=0.05) in mercury concentration between Chinese crayfish (x=0.059 [micro]g/g wet weight) and Louisiana crayfish (x=0.027 [micro]g/g wet weight). Fresh crayfish were also analyzed and these results were not significantly different from the locally processed crayfish. The results fall below the action limits established for mercury by both the FDA (0.5 [micro]g/g) and the EPA (1.0 [micro]g/g), but the average meat of crayfish may exceed the reference doses for both men and women.
Schuler, L.J. and M.G. Heagler. McSU. A comparison of the effects of salinity and chloride ion on the bioaccumulation of cadmium in Menidia beryllina, the Tidewater Silverside.--Cadmium accumulates in fish during waterborne exposure. Water chemistry determines which species of cadmium are dominant in each system and speciation of metals in water determines their bioavailability. In previous work, Menidia beryllina, tidewater silverside, was exposed to 35 [micro]g/L cadmium with varying salinity from 0 [per thousands] to 20 [per thousands] for a 29 day exposure period. The results indicated an inverse relationship with fish in the highest salinity accumulating the least amount of cadmium (1.50 [micro]g/g). The present study examines the hypothesis that the cadmium-chloride complex is the major mechanism controlling uptake across gill membranes. Menidia beryllina was exposed using following the same protocols used in the previous study with the exception of varying only the chloride ion by the addition of NaCl.
Al-Dujaili, J. and B. Ortega, LSUE. The microbiology of independent water systems in the Southwest Louisiana area.--Clean, healthy drinking water is very important to a community's health. Many people rely on well water was their source for drinking water in the Southwest Louisiana area. The microbiological quality of private well water from 30 residences was studied. Data concerning Waterhouse parameters were obtained through the distribution of written questionnaires to family members at each sample site. A variety of factors that might influence the bacteriological quality of water dispensers was examined (e.g. aerobic and facultative anaerobic heterotrophic bacteria, total coliform, E. coli, Aeromonus sp., and Biological Oxygen Demand (BOD)). It was found that 85% of the well water from the residences were contaminated by at least one coliform or indicator bacterium. This study also found that 57% of well water samples were contaminated by at least one Aeromonus sp. Meanwhile, the BOD value ([less than or equal to] 0.09 mg/L) was found in 98% of well water. Moreover, we obtained an HPC of at least [10.sup.3] CFU/ml for 34% of the tap water.
Beadle, J. and K. Manivannan. SLU. Study of ion channel currents in the circadian pacemaker neurons of Bulla gouldiana.--Most of our present understanding of the cellular mechanisms of timekeeping comes from the study of the marine snail Bulla gouldiana. Recently electrical currents through the ion channels of the basal retinal neurons (BRN's) have been shown to exhibit a circadian rhythm. We present our findings and describe some of the techniques used for cell preparation, isolation, and ion channel current measurements. The goal of this project is to understand the relationship between ion channel gating and the circadian clock. Work supported in part by the LEQSF Grant (1995-98)-RD-A-21 and a Faculty Development Grant to K.M. and a SLU OSCAR grant to J.B.
Bounds, H.C. NLU. D.M. Griffin, Jr. LTU. Anaerobic activity in a rock plant filter system.--Several standard wastewater monitoring tests, especially Biochemical Oxygen Demand (BOD), are biased toward aerobic-facultative metabolism. This project examined the use of on-site tests for oxidation-reduction potential (ORP) and [H.sub.2]S concentration, as well as laboratory determinations of the rates (mg/h) of [H.sub.2]S and volatile fatty acid production, and colony forming units (CFU/ml) in anaerobic agar as a means of determining anaerobic activity. All the parameters correlated well with each other and are suggested as procedures for future study of anaerobes in wastewater systems.
Fenoli, C., K. Sellers, K. Woods, P. Dollar, C. Duncan, D. Sanders, and S. Hecht. NLU. Bacterial contamination of hunter cover scents.--Deer hunters sometimes purchase commercial products to use in masking the human scent. These products are often based on urine obtained from wild animals, such as deer, fox, and other native species. The instructions for use of these products vary, but may include direct application to skin or clothing. It is known that zoonotic diseases are sometimes transmitted to humans by urine; one example is leptosporidiosis. Culturing of a number of different purchased cover scents revealed that many were contaminated with bacteria, especially gram negative bacilli. We report our preliminary findings on usage of these scents, concentration of bacteria from different samples, and identification of potential pathogens. This work was supported by LEQSF Grant (1998-00)-ENH-TR-61 to S.H.
Hecht, S. and S. Long. NLU. Using RE-PCR to obtain genomic integration regions of endogenous proviruses.--Little is known about the transposition and movement of endogenous proviruses in mammalian genomes. Most studies of endogenous retroviruses have used Southern hybridizations to characterize shared integration sites, such as investigating oncogenic events in the cell. However, actual sequence data would allow mapping of integration regions and may reveal sequence specific data. We are investigating a unique family of retroviruses that are spread throughout ungulate germlines. A comparison of this family of type B/D viruses in sheep and goats reveals numerous proviruses. A catalogue of integration regions would allow us to compare the sites chosen in the two different host genera, and also may reveal which of the viruses were spread by integration into a common ancestor and which ones are still active. Using a method involving primers specific to the virus LTR regions and primers to restriction enzyme sites, we were able to clone integration regions directly from cattle, sheep, and goat genomes. Implications of this will be discussed.
Kilgen, M., J. Bourgeois, and C. Porche. NiSU. Hydrostatic high pressure processing of Louisiana shellstock oysters for Vibrio vulnificus control and for mechanical shucking.--Hydrostatic high pressure processing (HHP) was evaluated for the elimination of Vibrio vulnificus from live Louisiana oysters. Four samples of 50 shellstock oysters from the same harvest site were treated at 45,000 and 50,000 pounds per square inch (psi) for 5 minutes and 10 minutes each. V. vulnificus was reduced from 9.3 X [10.sup.3] MPN/gram ambient levels in control samples to nondetectable levels in all 4 treated groups. Total aerobic plate counts (APC/g) were reduced 2 and 3 logs respectively at 50,000 psi for 5 and 10 minutes. Oysters were also mechanically shucked at all test pressures. The commercialization of this technology will revolutionize the labor-intensive oyster industry, and result in a significant economic benefit of an estimated increase in the oyster industry value over a 2-3 year period by $20 million annually.
Roberts, C.N. and D.W. Buckalew. XU. Incidence and lateral distribution of arbuscular mycorrhizae in soils in a freshwater ecosystem.--Poster presentation.
Roma, G. and H.C. Bounds. NLU. Isolation of Salmonella species using antibody-coated stirring bars.--A novel procedure using either antibody-coated paper disks with metal clips or antibody-coated stainless steel wool formed into a micro "stir bar" has been shown to increase sensitivity and decrease isolation time for the recovery of Salmonella species from environmental samples. The procedure utilizes the vortex activity of mixing to increase the absorption of salmonella to the disk or stainless steel bar and eliminates at least 18 hours from the standard method.
Singh, P. and B. Blaylock. NLU. Oral exposure to butoxyacetic acid (BAA) does not mimic the effects of its parent compound, butoxyethanol (BE), on systemic immune responses in BALB/c mice.--Immunomodulatory effects of glycol ethers have been studied in several rodent models. Previous studies in our lab indicated that 10-day oral dosing with 2-butoxyethanol (BE) enhances systemic immune responses in female BALB/c mice. The objective of this study was to determine whether oral dosing with BE's primary metabolite, butoxyacetic acid (BAA) would produce the same enhancement. Mice were given either 0, 50, 150 or 400 mg/kg/day BAA for 10 days by oral gavage and sacrificed 72 hours later for assessment of systemic immune parameters. We found no significant effects on lymphocyte blastogenesis in response to either B- or T-cell mitogens (lipopolysaccharide and concanavalin A, respectively). There were no significant effects on blastogenesis in the mixed lymphocyte response. We also observed no differences in natural killer cell activity or in cytotoxic T cell activity among any of the BAA doses when treatment groups were compared to the control group. Based on these findings, it appears that the immunoenhancement observed with oral BE administration is not due to the action of BAA. Poster presentation.
Coley, D. and J.L. Carr. NLU. Ecological parameters of the turtle assemblage in a north Louisiana farm pond.--Aquatic turtles were collected from the Layton Farm pond of NLU between April 1997 and October 1998. The pond has a surface area of 2-3 acres, with high turbidity, an extensive littoral zone, and very little submergent or emergent aquatic vegetation. Turtles were captured with either a basking trap or baited hoop-style net and returned to the laboratory for data collection. For each specimen, species, gender, weight, and shell measurements were recorded and each was individually marked before being returned to the pond. The turtle species and numbers collected (number of individuals+number of recaptures) were Chelydra serpentina (2+0), Stemotherus odoratus (5+2), Pseudemys concinna (9+0), and Trachemys scripta (49+28). The species composition is similar to that of other small, unproductive bodies of water and the density of sliders is comparatively low. Poster presentation.
Doucet, J. NiSU. M. DeAngelis. LSUMC. S.M. Robichaux. NiSU. P. Deininger. TuMC. M. Batzer and B. Keats. LSUMC. Assessing the candidacy of new genes at the Acadian Usher Syndrome locus.--The Usher Syndromes are autosomal recessive disorders characterized by both deafness and retinal degeneration. A gene for Usher Syndrome (USH1C) is segregating in a small, southwestern Louisiana population of Acadian descent. We have localized USH1C to the short arm of chromosome 11 within 400 kb of anonymous marker D11 S921. From the nucleotide sequence of this critical region, we have predicted at least twelve exons of previously unlocalized genes. Using a combination of exon end-amplification (RACE) and cDNA library selection with exon probes, we are in process of finding corresponding full-length cDNAs, which will enable both mutation analysis of entire coding regions and assessment of these newly-localized genes as USH1C. Supported by USPHS DC00379 (BK) and LEQSF (1998-01)-RD-A-19 (JD).
Grayson, J.C. and A.M. Findley. NLU. Intraerthyrocytic parasites of turtles collected from northeast Louisiana.--Peripheral blood samples collected from various turtle species were examined for the presence of intraerythrocytic parasites, Haemogregarina sp. and a cytoplasmic inclusion body of possible prokaryotic origin were consistently observed in all turtles. Parasite load (total percent of red blood cells infected) are presented for Layton Farm Pond (NLU campus) and Black Bayou Lake (Ouachita Parish) collection sites. Differences in infection rates are shown as a function of the particular turtle species samples and data from two spring/summer collection periods are compared. The persistence of Haemogregarina sp. infections in the absence of the intermediate leech host is also discussed.
Green. B.A. XU. Creating an organism: linking learning objectives, teaching strategies and outcome assessment techniques.--Students in Comparative Vertebrate Anatomy are required to learn an enormous amount of structural data in an evolutionary context. The students demonstrate the mastery of this learning objective by A) the creation of a living organism, the environment or niche in which it lives and the evolutionary forces which have acted or are acting on it: and B) the justification of the designed scenario. This creative writing assignment corresponds to Bloom's Taxonomy of Cognition Levels #5/synthesis and #6/evaluate. At XU, almost 100% of students in this course are Pre-Med. These cognitive skills are critical for their success in medical school and need to be developed. This study was funded by The Center for the Advancement of Teaching at XU. Poster presentation.
Greenbaum, E.B. and J.L. Carr. NLU. Sexual differentiation in spiny softshell turtles (Apalone spinifera).--In turtle species with TSD (temperature-dependent sex determination), it is advantageous to delay sexual differentiation as long as possible. Since the turtle A. spinifera has GSD (genetic sex determination), it is hypothesized that it will sexually differentiate sooner than do TSD species. Staging criteria were found by gross examination under a dissecting microscope. This was done in order to facilitate comparison with similar stages of embryonic development among various turtle species. Gonads were examined by histological sectioning procedures and measured with image analysis software. Trends were seen between gonadal length and sex, stage, and incubation temperature. Histological examination identified the stage of sexual differentiation as 19 (Ynetema stages). Although sexual differentiation takes place at about the same stage as in other turtle species (stages 18-20), the fact that A. spinifera has GSD means that this differentiation is irreversible at this stage.
Hood, C.S., LU, TU * and N.T. Vu, LU. * Tulane Univ. Mus. Nat. Hist., Belle Chasse, LA. Geographic variation and sexual dimorphism in Louisiana populations of the muskrat, Ondatra zibethicus.--The muskrat, Ondatra zibethicus, is naturally distributed throughout much of North America. Populations inhabiting the Texas and Louisiana Gulf Coastal region represent an isolated portion of the species range (Lowery, 1974). In 1948, Gould & Kreeger published a cranial morphometric study (n = 357) of three Louisiana populations (St. Bernard, Vermilion, and Cameron parishes) noting a geographic trend in size from west to east across the state. The present study re-analyzes Gould & Kreeger's original data (9 cranial measurements) and applies multivariate analyses to test for sexual dimorphism and geographic variation. In the re-analysis, 2-way MANOVA of the original measurements was computed for specimens with no missing values (n = 340). Highly significant sexual dimorphism and geographic variation exists in the skulls and mandibles of Louisiana muskrats. Ongoing studies are evaluating rates of morphological evolution, morphological integration, and the role of environmental stress on these populations.
Liberatos, J.D. and P. Hance-Mobley. LTU. Biomphalaria glabrata: transfer of factors governing resistance to Schistosoma mansoni.--The parasite, Shistosoma mansoni, uses snails as intermediate hosts. S. mansoni susceptible and resistant strains of B. glabrata snails exist. In an attempt to elucidate the factor(s) governing resistance, hemolymph, hemocytes, and serum were taken from two resistant strains (BS-90 and 13-16R1) of B. glabrata, and one of the three fractions was injected into S. mansoni susceptible snails; untreated, susceptible snails served as controls. Recipient snails were separated into six groups and each group received a different fraction (hemolymph, hemocytes, and serum) from one of the two resistant snails. All of the experimental and control snails were exposed to S. mansoni and later checked for the quantity of parasite produced by each group. Experimental snails that received the BS-90 serum fraction produced no cercariae throughout the experiment, while the other experimental snails produced low numbers of cercariae compared to the control snails.
McPherson, A.B. CC. Louisiana's Cretaceous vertebrates.--Cretaceous outcrops in Louisiana are very rare, and even less common is the prospect of finding vertebrate fossils in these strata. Collections made by the author from the Rayburn Salt Dome demonstrate that several species of cretaceous sharks, teleostian fish and a mososaur inhabited our Cretaceous sea.
Paulissen, M.A. and H.A. Meyer. McSU. Does toe-clipping reduce the ability of the Mediterranean gecko lizard to cling to vertical walls?--The Mediterranean gecko, Hemidactylus turcicus, lives on the sides of buildings in Louisiana. A standard way to mark lizards for identification is to clip their toes, but this practice may reduce the ability of geckos to cling to walls. We tested this possibility by conducting the following study. Each of 32 adult geckos was fitted with a harness and placed on a vertical brick wall. Metal washers were then added to the harness until the gecko fell off. Half the geckos were then toe-clipped, the other half were used as a control and all geckos were retested the next night. Toe-clipped geckos held significantly less weight the second night of testing (after toe-clipping) than they did the first night; the decline for control (non-toe-clipped) geckos was not significant. However, the mean decline in weight held between the first and second nights of testing did not differ significantly between the two groups.
PHYSICAL SCIENCES DIVISION
Allen, J. SLU. Recent developments in ion selective electrodes for anions.--With ion-selective electrode (ISE's), the potential is related to the activity of the ion in a sample by the Nernst equation. While ISE's for cations are well developed, this is not true for anions. In about the last ten years this has started to change with the introduction of ionophores (compounds that interact with ions) that form complexes and adducts instead of the nonspecific interactions of the past. This has lead to development of more ISE's for a larger variety of anions. This presentations will addresses the changes in this field.
Aucoin, J., R. Blanchard, B. Boudreaux, D. Schultz, K. Mandhare, and J.N. Beck. NSU. Concentrations of the trace metals Cr, Cu, Pb, and Zn in fish and sediment samples taken from Lake Boeuf, southeastern Louisiana.--The trace metals Cr, Cu, Pb, and Zn were measured in fish and sediment samples taken from Lake Boeuf, located in Southeastern Louisiana. Lake Boeuf is a popular recreational fishing lake from which the following sunfish are caught and consumed: bluegill (Lepomis macrochirus); redear (Lepomis microlophus); largemouth bass (Micropterus salmoides); and black crappie (Poxomis nigramaculatus). Metals were extracted from the fish and sediment samples using microwave digestion techniques. The metal concentrations were quantified using standard flame atomic absorption spectroscopic methods. The concentrations of trace metals in fish did not vary with species or weight of fish, however, a seasonal trend in metal concentration was observed. The concentrations of Cr varied from 2 to 15 [micro]g/g, Cu from 0.2 to 4 [micro]g/g, Pb from 0.5 to 9 [micro]g/g, and Zn from 10 to 20 [micro]g/g. The metal concentrations in the core samples did not show a history of inputs of pollutant metals to the lake.
Brotherton, H.O., and M. Xiao. NLU. Evaluation of lead levels in edible fish tissue.--Levels of heavy metals in fish tissue have become a point of concern for environmentalists in Louisiana. Primary focus has centered on the levels of mercury in edible fish tissue and extensive studies have carried out on the fish populations of innumerable fresh and salt water bodies within the bounds of the state of Louisiana. Studies to determine levels of other heavy metals in fish tissue are ongoing in our laboratory and preliminary results have led use to concentrate our efforts on heavy metals such as lead. We have evaluated the levels of lead in over 100 samples of edible fish tissue from various species and locations within the state of Louisiana. Although elevated levels of lead do not appear to be present in a significant number of samples, an evaluation of lead levels based on location and species as well as a comparative evaluation of levels of lead with levels of mercury by species are of interest.
Darbeau, R. W. and E.H. White. McSU. The use of deaminatively-generated carbocations in organic synthesis.--Deamination produces an inert-molecule-separated carbocation-counterion ion-pair, the cation of which is exceedingly reactive. Although these carbocations are accessible via a number of routes, the N-nitrosamide route is superior because of the mildness of the conditions necessary, high reactivity of the cations, solubility of the precursors in a wide range of solvents, Mde range of decomposition temperatures possible, straightforward chemistry, and excellent product balance. This paper describes the utility of the nitrosamide approach to the first direct alkylation of [Pi]-rich heteroaromatics, to the preparation of unsymmetrical diacylamines, and to polymerization.
Delaney. M.S. and R. Dalberg. McSU. Steric effects of non-cyclopentadienyl ligands in ethylene polymerizations utilizing bis-substituted titanocene catalysts.--The steric effects of the non-cyclopentadienyl ligands in bis-substituted titanocenes used as catalysts for the polymerization of ethylene was investigated. MAO was used as cocatalyst. The substituents investigated included chloro, methyl, phenyl, o-carboranyl, and o-methylcarboranyl. The polymerizations carried out in toluene with 100 psig ethylene and 1X10-5 M in titanium. Results were gauged by yields and approximate molecular weights. Molecular modeling of the systems suggests that the inhibition due to steric size may be in the reduction/activation step and not in the docking of ethylene or the first insertion.
Dillard, S.S. and D.E. Hubbard. GSU. Polymerizable monomer reactants polymer composites.--An oxydianiline monomer, 2,2'-bis(p-aminophenoxy) biphenyl, has been reacted with 3,3',4,4'-Bezophenone tetracarboxylic dianhydride to prepare polymer resins. The polyamides formed after heat curing are strong candidates for carbon/carbon graphite fiber composite materials. Based on the thermal properties of these resin materials, we propose to formulate in situ carbon reinforced composites. Poster presentation.
Dupre, T.P., T.J. Granier, S. Keife. R. Marino, S. O'Rourke, C. Partridge, D.L. Schultz, K. Mandhare, and J.N. Beck. NSU. Variation of mercury in fish taken from lake Boeuf, southeastern Louisiana.--The concentration of mercury was measured in a variety of fish and sediment cores taken from Lake Boeuf located in southeastern Louisiana. Lake Boeuf is an important recreational and game fishing lake from which the following sunfish are caught and consumed: bluegill sunfish (Lepomis macrochirus), redear sunfish (Lepomis microlophus), largemouth bass (Micropterus salmoides), and black crappie (Poxomis nigromaculatus). These species of fish were collected and mercury levels were determined using the EPA cold vapor analysis method 7471. Mercury concentrations exceeding the EPA action level of 0.5 [micro]g/g in fish caught by fishermen were found in 4 of 15 bluegill sunfish and 2 of 15 black crappie. Bluegill sunfish contained the highest concentrations of mercury, ranging in value from <0.02 to 0.92 [micro]g/g and an average of 0.22 [+ or -] 0.31 [micro]g/g. Redear sunfish had the lowest concentration, averaging only 0.03 [+ or -] 0.03 [micro]g/g. Sediment cores revealed a history of mercury inputs to the lake with concentrations as high as 0.25 [micro]g/g at depths of about 15 cm.
Feske, B., S. Morrison, and J. Allen. SLU. Long-term monitoring of nitrate at Turtle Cove.--This research deals with the analysis of nitrate, which plays a strong role in the nitrogen cycle. Nitrate is also a fertilizer that can be found in sewage waste and is the main contributor to algae blooms in the ocean. The samples are taken from SLU's research station in Turtle Cove. Two representative samples are taken from each spot of the tributaries and canal of Pass Manchac. The amount of nitrate in the samples are analyzed by UV-VIS and also with an ion-selective electrode. This will give an indication of the fluctuations of nitrate over a period of time. Poster presentation.
Fitzgerald, K.C., III and F.E. Collins. LSU-S. The 2.5% solution.--The efficiency of nine drying agents was evaluated on four aprotic solvents by use of a liquid scintillation method that involved the use of water laced with tritium. Also, the amount of drying agent was reduced by one-half of the standard 5% wt/vol in order to determine if excess desiccant was being used in many laboratory procedures. It was surprising to learn that under the conditions used in our study the lesser amount of drying agent proved sufficient.
Germany, T., W. Griffith, J. Salim, and C. Walton. GSU. Synthesis of a N, N-alkylated-amino, nitro-fluorenone monomer.--This presentation will focus on the synthesis of a N, N alkylated-amino-nitro-fluorenone monomer. This synthesis is a three step process, with the first involving the selective reduction of 2,7 dinitro fluorenone. The amino fluorenone derivative is the N, N alkylated using triethy phosphate. The monomer is obtained by reacting the fluorenone with excess aniline under acidic conditions.
Granger, G.J. and F.H. Walters. USL. Regression models in corrosion.--Data from 23 wells (15 parameters) were used to develop corrosion models, Linear, log and loglinear models were developed using multiple linear regression and robust regression techniques. Isolation of 3 outliers resulted in similar models. Prediction of corrosion rates is the ultimate aim of this work and the models are screened as to their suitability and predictability.
Guzzetta, G., D. Berryhill, and G.V. Lo. NiSU. Correlating dissociation constants of substituted benzoic acids with structural properties.--The program Molecular Modeling Pro was used to generate a database with structural properties for 75 para-substituted and 75 meta-substituted benzoic acids. The program Molecular Analysis Pro was used to correlate known dissociation constants with the calculated structural properties and the best correlation was found to be with dipole moment and molecular weight.
He, Z., D.P. Dawson. NLU. Catalytic reduction of hydrazones.--Amines make up an important class of compounds. Our group has been concerned with making biologically active amine compounds. In particular, we have been interested in making compounds that are agonists at the alpha two adrenergic receptor. We started with compounds known to have alpha two agonist activity like Guanabenz. We then made changes to determine if the changes were beneficial or detrimental to biological activity. Our research centers on the catalytic reduction of aminoguanidine hydrazones to aminoguanidine hydrazines. This paper will deal with the reaction conditions that were found to give high yields of the corresponding hydrazines. Different metals, varying concentrations of catalyst, and different hydrazones were used to get optimal conditions. Conditions were used that generated racemic mixtures but will be amended to give chiral aminoguanidine hydrazines. Poster presentation.
Lattier, A. and D.E. Hubbard. GSU. Synthesis of poly(ether)amides.--An oxydianiline, (p-aminophenoxy)biphenyl, has been reacted with nadic ester, para-phenylene diamine, and 3,3',4,4'-Benzophenonetetracarboxylic dianhydride to prepare various polymer resins. Thermal stagging studies have been performed on the resins and the results of these studies have been measured using differential scanning calorimetry (DSC).
Morrison, S., B. Feske, and J. Mien. SLU. Nitrite ion-selective electrode in water analysis.--Nitrogen is found in nature in several different forms, one being nitrite (N[O.sub.2.sup.-]). The purpose of this research is to determine if a nitrite ion-selective electrode can replace classical methods (i.e. UV-Vis) of nitrite detection in water analysis. The ion-selective electrode is made using a nitrite selective membrane, facilitated by a nitrite sensitive ionophore. The said ion-selective electrode relates the potential (in millivolts) to the activity of the ion, in this case nitrite. A calibration curve is created using standards of known concentration, and the concentration of the unknown samples can thus be calculated. Poster presentation.
Mule, C., S. Delee, and B. Wurm. SLU. Atomic absorption analysis of heavy metals in Lake Pontchartrain blue crabs.--Blue crabs collected from two different sites in Lake Pontchartrain were tested for Pb, Cr, and Hg contamination. Heavy metals were extracted from the fatty tissue of the crabs. The utility of using a pre-concentration technique followed by flame atomic absorption spectroscopy for determining heavy metal contamination in the part per billion range is demonstrated. Poster presentation.
Richardson, F. and D.E. Hubbard. GSU. Using the TI-83 graphing calculator to conduct experiments in General Chemistry.--The TI-83 graphing calculator is used to collect and plot data during experiments which show the relationship between wavelength and energy. We have found fascinating ways in which to report the data observed, and to evaluate the experimental data using various graphing methods. Poster presentation.
Simon, R. and A.A. Gallo. USL. Synthesis of phenylhydroxamic acids.--The synthesis of several phenylhydroxamic acids was undertaken with the ultimate goal of derivatizing these acids for routine methods of analysis. The hydroxamic acid functional group is important in antibiotics, metal chelation, and enzyme inhibition. N-phenylhydroxylamine was prepared by the reduction of nitrobenzene with Zn dust. Acid chlorides were synthesized from the corresponding carboxylic acid and thionyl chloride. The reaction of N-phenylhydroxylamine and an acid chloride to produce the phenylhydroxamic acid will be discussed. Poster presentation.
Srivastava. R.S. USL. K.M. Nicholas. University of Oklahoma. Iron catalyzed allylic amination by nitroorganics.--We have reported that phenyl hydroxylamine as efficient aminating agent in metal catalyzed allylic amination of olefins. Recently, we have discovered a new allylic amination system which employs nitroarenes as aminating agent and inexpensive [[cpFe[(CO).sub.2]].sub.2] as catalyst according to equation under reducing condition. A coordinated organonitrogen species is implicated as the active aminating agent. Results of these experiments will be presented.
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Zhang, J., F. Payton, and A. Murty. XU. A.N. Murty. GSU. Synthesis of ferric molybdatemolybdenum trioxide catalysts by pyrolysis of organic precursors.--Highly dispersed ferric molybdate-molybdenum trioxide catalysts that are proposed to be used as a catalyst for coal liquefaction have been synthesized by pyrolysis of organic precursors. They were formed by the rapid dehydration of the solution containing all necessary metal ions and citric acid. The organic precursor samples with varieties of chemical composition have been studied with TGA, DTA, and DSC to understand the thermal decomposition process. The thermal analysis reveals the occurrence of an exothermic reaction at 200 [degrees] C and an endothermic reaction 670 [degrees] C. Both reaction temperatures increase with increasing molybdenum content. The catalysts were characterized with FTIR and XRD. The particle size was determined by line broadening in XRD, and its correlation with reaction condition has been studied. Work supported through a grant from DOE. Poster presentation.
Zippi, E.M., R. May, M. Hoffmeyer, P. Landry, H. Stone, and I Thompson. LSU-S. Sulfonation of porous poly(styrene) for use in PET.--The sulfonation of poly(styrene) is one of the steps in the synthesis of a carbon rich target material for die cyclotron production of nitrogen-13 ammonia, a radiopharmaceutical agent used in Positron Emission Tomography. Porous poly(styrene), cross-linked with divinylbenzene (DVB), has been prepared via emulsion polymerization and sulfonated by a variety of methods. The sulfur content of each sample has been determined by titration of the acidic -S[O.sub.3]H proton with base. Similar work on poly(styrene) resins made by suspension polymerization has been presented. A comparison of the extent of sulfur incorporation onto poly(styrene) samples from each of these polymerization techniques will be made. Tins research is supported by the Biomedical Research Foundation (BRF) of Northwest Louisiana and BoRSF. Poster presentation.
Computer Science Section
Deramus, Y., Travis T., and Y. Reddy. GSU. Internet filtering model for public libraries and schools.--Through the Internet, libraries and schools now provide easy, efficient access to a world of information that stretches far beyond the confines of traditional learning facilities. Unfortunately, when young readers search the Web to find information for school assignments or to fulfill a general love of learning, they are bombarded by objectionable material. Internet filtering is a process that prevents or blocks access to certain material on the Internet. Libraries and schools have turned to Internet filtering devices as a solution for this problem. Still the filtering is not 100% effective. The present research reviews the available filter devices and proposes an efficient filtering model for such places as public libraries and schools wherever children have access to Internet.
Edwards, L. GSU. Numerical computation of electric field distribution around a polluted insulator.--In this paper, the electrostatic field distribution around a polluted insulator is computed using a finite difference scheme. The finite difference method determines the potential distribution over the insulating surface. The electric stress distribution is calculated at different points on an insulating surface along its length. The partially wet insulator in an ambient air medium is modeled as an axisymmetric system. The occurrence of sudden flash over on a partially contaminated insulator with a wet band varying in length along the length of the insulator is investigated. The results of the computations are in agreement with the experimental observations made by other authors.
Johnson, S. and R. Meyers. GSU. Visualization for scientific computing.--This research investigates the scientific visualization of the solution of partial differential equations. The first application has been to the advection-diffusion equation. Advection-Diffusion processes are common in many physical phenomena. Advection-Diffusion equations represent these phenomena mathematically and used in such diverse applications as global climate modeling, weather forecasting, medicine, oceanography, aerodynamics, chemical mixing, air pollution and fire modeling. While the advection-diffusion equation solution is unique, its approximate solution can deviate from the analytical solution by an amount depending on the nature of the approximation. Finite difference solutions of the advection-diffusion equation were developed and programmed in Matlab. A user-interface was developed also using Matlab to display the solutions, and the effect to alter the initial and boundary conditions and parameters. Plots of the solution results were generated in Matlab and some work has been done to include animations of the development of the solutions, comparisons of the results of various methods, and error bound graphs. Future efforts will be applied to fluid dynamics and alternate visualization concepts.
Reddy, Y.B. and J. Wall. GSU. Genetic algorithm approach to relevant information filtering.--Relevant Information Filtering (RIF) is used to describe a variety of processes involving delivery of unstructured or partially structured streams of data to relevant people. In the Distributed Interactive Simulation (DIS) environment the commander broadcasts the commands to various groups of subordinates that are participating in the war. The commands are the data streams produced from a commander in a changing environment (most of the time). The filtering has to adapt the changing environment so that it will be effective. The changes may occur both on the transmission side (the nature of the streams can change) and on the reception side (the interest of users and type of users can change). This paper presents an adaptive information filtering system that learns from user feedback and behavior. We use a genetic algorithm based machine learning approach called Classifier System (CLS) that combines syntactically simple rules called classifiers, parallel rule evaluation, rule rating and conflict resolution by analogy to a competitive service economy. The research was supported by the Army Research Office.
White, I. C. NiSU. Scientific analysis of a water ski jumper.--The sport of water skiing has been nominated for inclusion in the 2004 Olympic Games. Jumping is the most exciting and dangerous event in water skiing. The person who jumps the farthest determines the winner of the jumping event. Jumpers can reach speeds of 60 mph, heights of 27 feet and distances of 220 feet. In several Olympic sports, computers are being used to help coaches analyze an athlete's technique to help improve performance. A novel device was created that performs real time data acquisition to measure the force a skier places on the boat and the angle that the force is applied. The skier's path and force generated are then plotted and analyzed to help improve a skier's technique.
Earth Science Section
Batchelor, J.W. McSU. Synthesis of the western Pacific Ocean resulting from multiple K-T boundary impact.--Late Triassic maps show Australia south of a spreading axis. Current maps show it north of a spreading axis. I suggest that antipode forces separated Australia and Antarctica; moved Australia north; broke up the old Asiatic coast Darwin rise; moved it across the Pacific to the Baja Mexican coast; activated the Japanese and Kurile trenches; added a westward component to the Pacific plate movement; activated an immense western Pacific mantle plume; and caused the western Pacific to break out in a rash of volcanism.
Clarke, J.C. and B. Smith. NLU. Influence of landfalling hurricanes on tornado climatology in Louisiana. Tornadoes occur with a relatively high frequency across the state of Louisiana, with a climatological maximum during the month of April and a smaller maximum in November. However, a small peak is found during the month of September. It is a well recognized observation that landfalling hurricanes often generate tornadoes northeast of and considerable distance from, the path of the eye. Using tornado data from 1950 through 1995 over the state of Louisiana compared with the timing of hurricane landfall over the same period across the western Gulf of Mexico, we address whether the observed peak of tornado activity is associated with these hurricanes.
De Hon, R.A., L.N. Glawe, P.A. Washington, and L.M. Young. NLU. Formation of northern Louisiana ironstones.--A belt of Middle Eocene ironstones of Cook Mountain time-equivalent formations stretches from east Texas across northern Louisiana into western Mississippi. The ironstone consists of goethite in sedimentary boxworks and concretions formed by in situ oxidation and hydration of lenses of "green sand" above the water table, as well as lenses of ironstone formed by leaching and precipitation. These green sands were assumed by previous workers to be glauconite. However, the green sand of the Kilpatrick Iron Ore District is identified by x ray diffraction as the 7[Angstrom], trioctahedral, clay mineral berthierine. Glauconite and berthierine originate under different environmental conditions. Glauconite forms by extremely slow accumulation on the outer continental shelf or slope, whereas berthierine forms in estuarine or prodeltaic environments. Thus, the environment of formation of berthierine strongly correlates with the marginal marine to fluvio-deltaic facies environment of the Cook Mountain Formation.
Emrick, C.M. and E.A. Pani. NLU. Climatology of the winds of the Red Sea.--The Red Sea extends from 30 [degrees] N to 12.5 [degrees] N and runs from approximately 36 [degrees] E to 43 [degrees] E. To the north, the Suez Canal connects it to the Mediterranean Sea, and to the south the Strait of Bab el Mandeb connects it to the Gulf of Aden. The winds of this region are dominated by a monsoonal flow, with a southwesterly summer monsoon and a northeasterly winter monsoon. Not only is there this monsoon, there are seasonal patterns to the winds over the Red Sea. Each season has its own distinctive pattern associated with it. Studying these winds and seasonal patterns has produced a climatology of the winds over the Red Sea.
Emrick, C.M. and R.A. De Hon. NLU. Catastrophic flooding through Labou Vallis, Mars.--Labou Vallis is a 270 km long, broad, shallow outwash channel of the Mangala Valles system. The valley carried outflow away from the main branch during a catastrophic flood event dud indurated much of Terra Sirenium in Hesperian time. Sheetflood flow across the Noachian Plateau ponded in depressions and craters until levels rose to breach crater rims and cut multiple spillways through the developing valley. As discharge trough the system continued, early-formed anastomosing channels were abandoned, and a single channel was established. Discharge through the narrowest part of Labou Vallis was the controlling mechanism for the final stage of outflow from the region. This part of the channel is 2 km wide, less than 500 m deep, and has a gradient of 0.004. Current studies are directed toward determining the discharge and duration of flow through this part of the channel.
Glawe, L.N. NLU. Foraminiferal environments of Paleocene (60 my) Wilds and Lower Nichols sands.--Depositional environments of these Paleocene subsurface units are interpreted from conventional cores taken from the Mary T. Smith et al. No. 1 well in Concordia Parish, Louisiana. These sands are components of the deeply buried Holly Springs delta complex of central Louisiana/southwest Mississippi. The distribution of marginal marine species of Foraminifera is controlled primarily by variations in salinity. Analysis of foraminiferal assemblages contained in core samples in terms of salinity-indicator genera, relative abundance of arenaceous and calcareous specimens, and comparisons with the distributions of Recent Foraminifera provide a basis for interpretation of Paleocene marginal marine environments. The Wilds Sand represents a distributary channel of a delta that prograded into the northern Gulf of Mexico during the Paleocene. The overlying Lower Nichols Sand records a sequence of hyposaline bayfill paleoenvironments that ranged from salt-water influenced lower bays to fresh-water influenced inner bays. Supported, in part, by NLU Foundation.
Gregory, J. and E. Pani. NLU. A climatology of the winds of the Red Sea.--Based on research of the United States Navy's operational global atmospheric prediction system (NOGAPS) harmonic dials over the Red Sea area, a statistical analysis was performed (including Fourier Transformations) utilizing the Spectra procedure. Fortran programs were written to extract NOGAPS wind components from a database and Statistical Analysis Software (SAS) was utilized for portions of the analysis. A review of the Spectra procedure and basic mathematics of a Frequency Domain / Harmonic Analysis will be offered. Results of the statistical investigation indicate climatological
anomalies, possibly moving systems throughout the Red Sea area, occur often during the two year period of 1995 and 1996 and at times less than a season.
Kontrovitz, M. NLU. Rare ostracodes for paleoenvironmental reconstruction: Nile Delta.--Ostracodes occur with low diversity and high abundance (up to 11,600 valves/g of sediment) in sixteen surface samples and several short cores taken from Lake Manzala (Nile Delta). Taxa included the abundant Cyprideis torosa (Jones 1850) and Sylvestra sp., and the rare Propontocypris sp., Loxoconcha elliptica Brady, 1868, Limnocythere sp., and Darwinula stephensoni (Brady and Robertson 1870). The rare species, also of small size here, allowed for subtle interpretations of environmental differences. For example, they alone indicate that only the northwestern part of the lake has a marked marine aspect, while the southwestern part has a distinct freshwater aspect. They would have been overlooked if standard practice had been followed, i.e., picking only 300 specimens in sieves with a mesh of 180 micrometers or larger. Thus, detailed paleoenvironmental interpretations of deltaic lakes are possible with ostracodes, if the full assemblage is used.
Miller, M. NLU. Paleoecology and biostratigraphy of reworked deposits from Toledo Bend Reservoir.--A reworked sand deposit at Toledo Bend Reservoir, Sabine Parish, Louisiana, has a variety of vertebrate and invertebrate fossils, including sharks, rays, mollusks, bryozoans and corals. Identification and analysis of these fossils reveal an inner to middle shelf environment with warmer water than the current Gulf of Mexico. Analysis of the fossil assemblage indicates a biostratigraphy that is Eocene in age. Comparison to other known Eocene assemblages indicates its likely source is the Cook Mountain Formation.
Morehead E.A. NLU. Mineralogy of iron deposits in north-central Louisiana.--Iron-rich sedimentary deposits within the middle Eocene, Upper Cook Mountain-Lower Cockfield sequence of North-Central Louisiana have been identified by previous workers as a sideritic glauconite/chamosite bearing unit based on field identification and bulk chemical composition. Reinvestigation of these outcrops reveals bands of concentrated goethite that developed within and below the one-to-eight foot thick green "sand." The green peloidal deposits are altered into boxworks of iron oxides, with green peloidal sediments concentrated into nodules one-to-four feet in diameter. The iron content within the boxwork alteration rinds increases outward from the nodules of green sediment. Samples were taken from green peloidal nodules, alteration rinds, and underlying oxidized layers from two areas in Claiborne Parish and from one site in Lincoln Parish. X-ray analysis reveals that the green peloidal nodules grade from a berthierine within the core, to siderite and berthierine in the inner altered layers to goethite in the outer layers.
Satterlee, D.R. NLU. Quebrada Tacahuay: not quite the oldest coastal site in South America.--Dating to almost 13,000 years ago, Tacahuay is one of only 3 sites in South America with such great antiquity. However, it is the only site in the New World with evidence of massive Paleoflood events caused by substantial El Nino inundations. This site contains more than 7 events that occurred before the 5,000 B.P. date for sea stabilization, at which time these climatic anomalies were thought to have first transpired.
Stringer, G. NLU. Additional species of otolith-based fishes from the Cretaceous Coon Creek Formation in southwest Tennessee.--A previous study of the Coon Creek Formation (Cretaceous, Early Maastrichtian) in McNairy County, Tennessee, revealed the presence of six species of fishes based on otoliths. Fishes included a congrid, polymixiid, trachichthyid, perciform, and two species of apogonids. Research on the laterally equivalent Ripley Formation in northeastern Mississippi produced 21 otolith-based fish taxa. The sediments at the two sites are very similar in composition. Further collecting of bulk samples in the Coon Creek Formation was undertaken to investigate the disparity in the number of species between the two sites. Otoliths were rare in the bulk samples of the Coon Creek, but did produce four more species of fishes: an albulid, a pterothrissid, a chlorophthalmid, and a pempherid. Analysis of various parameters seems to indicate a primary paleoenvironmental difference at the two sites as the reason for variation in the number of taxa.
Washington, P.A. NLU. Regional fracture patterns in northern Louisiana: evidence for three phases of compressional tectonics.--Preliminary mapping of natural fractures developed in coals, shales, and well-cemented silts and sands exposed in northern Louisiana has identified 6 fracture sets forming 3 orthogonal fracture systems with consistent overprinting relations. Each orthogonal fracture system consists of one fracture orientation that morphologically resembles a penetrative shortening fabric, in two cases paralleling thrust fault systems, and a perpendicular orientation that is morphologically an extension joint set. The regionally consistent orientations, morphologic characteristics, and overprinting relations across large areas of northern Louisiana suggest that these fracture systems are caused by regional tectonic events. The earliest fracture system includes pencils striking ~325 [degrees] and planar fractures at ~055 [degrees]. The second fracture system has strike-fractures at ~025 [degrees] (paralleling thrust faults in Mississippi) and planar fractures at ~290 [degrees], and the last system has strike fractures and thrust faults at ~80 [degrees] and planar fractures at ~010 [degrees].
Young, L.M. NLU. Petrology of the Wilcox Lower Nichols and Wilds sands (Paleocene), Mary T. Smith No. 1 well, Concordia Parish, Louisiana.--The Nichols Sand ranges from fine to very fine-grained sand and coarse silt in thin irregular laminations and burrow fillings in illite-kaolinite shale, with abundant concentrations of euhedral pyrite gains in its upper part. Sedimentary and metamorphic rock fragments are the dominant nonquartzose constituents. The underlying Wilds Sand is slightly coarser and less shaly than the Nichols but has basically the same framework grain mineralogy. Both sands range from lithic subarkose to lithic arenite. Cementation by quartz overgrowths is not extensive enough to seriously affect either primary or secondary moldic porosities, which range from 4 to 25%. The source of cement is probably silica released during burial diagnesis of interbedded and subjacent clays. Quartz grains in both the Nichols and Wilds sands show textural inversions that indicate a mixing of primary source and recycled older mature sandstone materials. Plagioclase and K-spar, as well as abundant polycrystalline quartz and metamorphic rock fragments, indicate crystalline source terranes. The most likely source area is the Southern Appalachians.
Mathematics and Statistics Section
McClendon, M.S. LSU-E. Enumeration of caterpillars.--A continuum is a nonempty, compact connected metric space, where a continuum tree is a continuum which has only a finite number of points (called non-out points) which, when removed from the continuum, do not separate the continuum into two disconnected sets. The research being presented is a method to determine the number of nonhomeomorphic continuum trees in a subset (the subset of caterpillars) of all continuum trees. This will be accomplished by finding a formula f(nd) which counts the number of nonhomeomorphic caterpillars that have n noncut points and a diameter of d.
Becnel, J.J. and D.A. Veith. NiSU. Locating equipotenial lines in the field of point charges.--The problem of finding the electrostatic potential due to a distribution of point charges is quite simple. The problem of finding a large number of points in the distribution which have the same potential so that an equipotential line may be plotted is simple in principle, but lengthy in execution involving a great deal of computation. In fact, it is difficult even to write an analytical equation which allows for the determination of one coordinate, given a potential value and the value of the other coordinate. A computer program for locating the equipotential lines in a distribution of point charges is presented.
Bedell, L.R., and M.D. Somers. NLU. CyberInteractor--a teaching and research tool demonstration.--An original computer-based tool dubbed CyberInteractor will be demonstrated, CyberInteractor facilitates immediate student feedback to an instructor and to other students in a classroom setting or over the world wide web for homework. Students view a question that can include multimedia, random numbers, and calculations involving the random numbers. After responding, they receive feedback (which is saved in a database for teaching research purposes) showing how other students in the same class have responded. Instructors can create and edit questions and question indexes over the web. Instructors can use the program to give pretests and posttests that enable them to compare the performance of their own students with students of other instructors and universities. Supported by NSF ILI DUE-9552258(1995-1997) and LaCEPT CRP(1997-1999)-07 through the Louisiana Board of Regents Quality Support Fund and NSE
Blanchard, G.T. SLU. Predictions of substorms following northward turnings of the interplanetary magnetic field.--Geomagnetic substorms are electromagnetic disturbances in the near-Earth space environment that have a disruptive effect on communication, power transmission, and satellite operations. It has been shown that, there is often a northward turning of the interplanetary magnetic field (IMF) just before substorms. Here we examine whether observations of northward turnings of the IMF can be used to predict the occurrence of substorms. We identified sharp northward turnings, predicted 17 substorms, and then searched for signatures of substorms onset around the time of the prediction. Of the 17 predictions, 10 were successful, and 5 failed. The failure of these predictions is explicable, however. These results indicate that at least some substorms can be predicted by measurements of the IMF.
diBenedetto, C.M. and D. Norwood. SLU. Study of polyelectrolyte viscosity in dilute, low ionic strength solutions.--Viscometry is a powerful polymer characterization technique, but extraction of polymer characteristics is frequently model dependent. Thus, it is of interest to experimentally constrain theories that model the viscosity of dilute polymer solutions in terms of the properties of the polymer molecules. It has long been known that the reduced viscosity of polyelectrolytes in low ionic strength solution presents a peak as a function of concentration (Fuoss, R.M. and U.P. Strauss. 1948. J. Polym. Sci., 3, 246, 602). Some models seek to explain this in terms of interactions of the polyelectrolyte molecules with other charges. Other theories explain the peak in terms of changes in the conformation of the polyelectrolyte. We present measurements of the viscosity of a very stiff polyelectrolyte xanthan, with a persistence length of about 1500 (Norwood, D.P., M. Benmouna, and W.F. Reed. 1996. Macromolecules, 29, 4293-4304), at very low added salt. The stiffness of xanthan minimizes conformation changes, permitting an investigation of the differences between the various models.
Fisher, P.L. NLU and J.E. Tohline. LSU. Numerical simulations of gas in galaxy disks.--Three-dimensional hydrodynamic simulations show that, in the absence of self-gravity, an axisymmetric, gaseous galaxy disk whose angular momentum vector is initially tipped at an angle to the symmetry axis of a fixed spheroidal dark matter halo does not settle to the equatorial plane of the halo. Instead, the disk settles to a plane located between the initial plane and the equatorial plane of the halo. While a purely stellar system in the same configuration would be destroyed by differential precession of the stellar orbits, the gaseous disk appears to be secularly as well as dynamically stable. Supported by NSF grant AST-9528424.
Gibbs, M., D. Washington, and M.A. Akundi. XU. FTIR studies of syngas interactions on Fe-Co-Mo[O.sub.3] composite catalyst.--Ferromagnetic metals Fe/Co/Ni along with other transition elements, supports and promoters makeup the most of the coal liquefaction catalysts. Particle size, morphology, state of the unfilled d-shells, unpaired electrons and the nature of the metallic charge distribution in the catalyst composite govern both the catalytic and spectroscopic behavior of the catalyst. Information on the catalytic yields using these catalysts is available in the literature. However, little effort has been devoted to correlating the physical and chemical characteristics of these catalysts. In this present study we investigated the surface characteristics of Iron-Cobalt catalyst with Molybdenum oxide as a support using Diffuse Reflectance Fourier Transform (DRIFT) spectroscopy. Six different catalysts with varying Fe/Co ratio and metal loadings of 25%, 15%, and 5% were prepared using co-precipitation technique. Catalysts were exposed to CO and CO+[H.sub.2] (Syngas) to investigate the bond character of the chemisorbed molecules by analyzing their vibrational frequencies. Preliminary results indicate the presence of vibrational frequencies mainly due to monodentate structures. Supported by grants from DOE and NSF.
Hussey, G. LSU and J. Trahan. CC. Drag on a sphere at low Reynolds Number.--Consider a sphere of diameter d falling at terminal velocity in a viscous fluid. Suppose that the Reynolds number is small, that the fluid is contained in a vertical cylindrical tube of diameter D, and that the sphere moves along the axis of the tube. The drag on the sphere is determined by two dimensionless numbers: the Reynolds number and the ratio d/D. We have made measurements of the drag (made dimensionless by the drag at zero Reynolds number in a fluid of infinite extent) over the range of d/D from 0.01 to 0.13 and of Reynolds number from 0.001 to 50. For Reynolds number less than 4, our results are consistent with the earlier work of Sutterby (1973). For Reynolds numbers above 4, the results for the dimensionless drag converge until at a Reynolds number of 20 or higher there is no longer any dependence on d/D. A simple empirical equation is found that works well in the limit of d/D approaching zero.
Ledbetter, C.R. and J. Lisantti. CC. A desktop PET scanner.--Positron Emission Tomography (PET) is a medical imaging modality which creates cross-sectional (tomographic) images of radionuclide distribution inside the human body using positron emitters and a PET imaging system. An inexpensive, small scale, fully functional dual-detector desktop PET system was built with imaging capabilities of 9mm FWHM. The system uses two stationary, collimated 2 X 2 NaI(T1) scintillation detectors. The amplified signals from the detectors are routed through NIM single channel analyzers and a variable window coincidence module set to 100 nsec. The TTL coincidence output is sent to a multichannel scaling card. The radionuclide distribution to be imaged is located inside a lucite phantom which is secured on a custom machined two piece aluminum gantry with rotational and translational degrees of freedom. Image reconstruction is performed using standard filtered back-projection algorithms using code generated in a PV-Wave programming environment. All reconstruction steps are displayed including sinogram creation, stepwise creation of the back-projected image, Fourier filtering, and the final image. Measured sensitivities and resolution of the device are primarily a function of detector collimation and angular and linear sampling distances. Present resolution is limited by the rigid sampling defined by the gantry baseplates.
Naidu, V.S., S. Patterson, L.T. Glands, and J.A. Prejean. GSU. W.-J. Sheu and G.A. Glass. SLU. Positron trapping at defects in gold implanted silicon.--Positron lifetime techniques were used to study the defects and the defect annealing in Au implanted Si. Isochronal annealing studies are performed to examine the kinetics of the defects. The positron lifetime spectra obtained after each annealing (between room temperature and 750 [degrees] C) were resolved into three components. The positron mean lifetime showed a two-step annealing out of defects in temperature regions 150-500 [degrees] C (slow annealing) and above 500 [degrees] C (rapid annealing). The second lifetime components, [[tau].sub.2] and [I.sub.2], and their variations with annealing temperature indicated that the vacancy defects are bound to Au impurities until 500 [degrees] C, where dissociation of these complexes occurred. A two-stage trapping model is used to estimate the positron trapping rates at vacancy type defects. The variations in the positron trapping rates with annealing temperature support the idea of Au impurity association and dissociation with the vacancy defects occurring at different temperatures. Work supported by ONR and DOE.
Nicholson, J.E. LSU-A. Teaching physics electronically via compressed video.--Physics for life science majors and physics for liberal arts majors delivered by compressed video offer challenges and necessitate changes in the traditional methods of delivery. Experiences gained in the process of teaching 5 physics classes by compressed video are shared. Techniques for course lecture, demonstration presentation, problem set assignment and delivery, test evaluation, help session scheduling, office hour attendance, Internet adjuncts, etc. are discussed. The methods of delivery for the two physics courses are compared and contrasted.
Schlecht, L.C.J. and K. Manivannan. SLU. Computer-aided description of interactively gating ion channels.--Electrical signaling in living cells is due to the flow of ions through transmembrane proteins called ion channels. Steady-state probabilities of gating (opening and closing) of ion channels normally follow a binomial distribution indicating the channels act independently of each other; however, in some preparations, there is evidence for interaction among the channels. Allowing only nearest neighbor interactions on a triangular lattice, we develop a computer-aided scheme to determine the gating probabilities of interacting channels. Work supported in part by the LEQSF Grant (1995-1998)-RD-A-21 and a Faculty Development Grant to K. M. and an SLU OSCAR Grant to L. S.
Somers, M.D. NLU. G. White. NSU. Upper-level Physics electives via videoconferencing on the Internet.--For the past three years faculty at Northeast Louisiana University and Northwestern State University have taught small upper level physics courses jointly on the Internet utilizing videoconferencing. Thus far our offerings have included modern physics, quantum mechanics, physics pedagogy, astrophysics, and computational and theoretical physics. We will demonstrate the various components of the courses, which include the web, email, Maple tutorial worksheets, selected physics software packages, Timbuktu (to control another computer from a remote site), as well as videoconferencing itself. We will also report on student and faculty perceptions of the relative merits of the different components. Supported by LEQSF 1996-1997 ENH-TR-49.
Turner, L., E. Bruster, T. Porter, S.V. Naidu, and A.N. Murty. GSU. M.A. Akundi. XU. Mossbauer and magnetization studies of iron-moly (Fe-Mo) catalysts: Effect of Syngas interaction.--The objective of this study is to examine the relations between magnetic and chemical properties of Iron-Molybdenum catalysts, which are extensively used in the direct liquefaction of coal. The catalysts were prepared with two different inter-metallic ratios: Fe/ Mo = 5% and 15%. The magnetic and Mossbauer characteristics of the samples were determined as: i) precursor (as prepared), ii) after exposing the sample to carbon monoxide, and iii) after exposing the sample to Syngas (a mixture of CO+[H.sub.2], CO/[H.sub.2], = 1). The Mossbauer data indicate that the electron configuration of iron is (F[e.sup.3+]) 3[d.sup.5] and is in a 6[S.sub.5/2] ionic state in a Fe-M[o.sub.3]O matrix in the precursors. When exposed to carbon monoxide, substantial quadrupole splitting occurs indicating that appreciable ionic charge production occurs in the lattice. In addition, CO adsorption leads to the production of F[e.sup.2+] species with an outer electron configuration 3[d.sup.6-x] 4[s.sup.x], x~10%. Adding hydrogen along with CO (Syngas adsorption) also generates F[e.sup.2+] species but with almost no 4s population, reaching a complete 3[d.sup.6] configuration. Both CO and CO+[H.sub.2] addition seem to result in charge transfer to the metal atom as well as to the lattice. The magnetization data show that the Fe-Mo composite is essentially paramagnetic and exposure to CO or CO+[H.sub.2] leads to the generation of a small amount of ferromagnetic species in the composite. Supported by grants from ONR and DOE.
Veith, D.A. NiSU. The inverted catenary.--It is shown in many standard Mechanics textbooks that a uniform rope or cable suspended from two fixed points assumes the shape of a catenary whose [Gamma]-coordinate can be written as a hyperbolic cosine function of the x-coordinate. It is shown here that such a cable suspended by a series of supports uniformly spaced along the cable assumes the shape of a series of catenaries. Further, if these supports meet certain conditions, the shape of the cable approaches that of an inverted catenary.
Wojtkiewicz, J., J. Lisantti, and J. Cannon. CC. A new approach to an approximation method in quantum mechanics.--We present a new approximation method for determining the energies and wave functions of one dimensional quantum systems that is mathematically related to the Raleigh Ritz variational method, but which is superior because it eliminates several of Raleigh Ritz's shortcomings. In particular, our method does not require an initial trial wave function, yields excited states and produces results to any desired accuracy. We use simple harmonic oscillator states as a basis for computing the eigenvalues of any quantum system. Mathematically this is equivalent to using, [PSI] = [C.sub.0]|[[psi].sub.0]>+[C.sub.1]|[psi].sub.1]; ea+ ... + [C.sub.n]|[[psi].sub.n]>, where the coefficients are the variational parameters. Within this basis we construct and diagonalize a Hamiltonian matrix to obtain the system's eigenvalues and eigenfunctions. By increasing the basis size we can use this method to obtain eigenvalues and eigenfunctions to arbitrary precision. To determine this method's practicality, we calculated the ground states for the known potential, [x.sup.4]. For modest size basis, (9 [less than or equal to] n [less than or equal to] 20), the ground state energy is within 1% of the actual value for 1 [less than or equal to] [omega] [less than or equal to] 10. Since basis sizes of up to 100 can be handled easily by computers, this method should reliably calculate the eigenvalues for most systems.
SCIENCE EDUCATION DIVISION
Adams, R.H. and G.L. Stringer. NLU. A multidisciplinary approach to reforming preservice mathematics and science.--The reform of preservice mathematics and science course offerings was initiated through the NLU LaCEPT-funded Campus Renewal Project. The current phase of the project has focused on developing multidisciplinary activities which integrate concepts of biology, chemistry, geosciences, physics, and mathematics. These activities were developed with the understanding that most elementary teachers are required to teach all subjects, yet they are not usually trained to understand the connections among these subjects and are not provided with materials that integrate the concepts of the various sciences and mathematics.
Aucoin, J.A., J.V. Chauvin, and G.V. Lo. NiSU. Investigating the "fish kill" phenomenon: laboratory activities for General, Analytical, and Physical Chemistry.--One important objective of science education reform is the incorporation of activities that involve relevant, real-world applications of scientific principles. Investigations of the "fish kill" phenomenon that occurs in Louisiana during the summer will be described. Dissolved oxygen levels in water samples from Bayou Lafourche and in air-saturated deionized water are measured with Texas Instruments Calculator-based laboratory systems and Hach kits. Results are interpreted in terms of Henry's Law, Le Chatelier's principle, and weather reports during a recent fish kill.
Borsari, B. LSU-E. Practical applications of the andragogical theory assumptions in introductory biology courses.--This study was conducted at LSU-Eunice to substantiate the four assumptions of Knowles' andragogical theory. Samples of students were given the opportunity to prepare independently for class presentations (in a topic of their choice), in three different biology courses. The purpose of implementing this innovative teaching technique was to allow students to replace an unsatisfactory test score and thus, according to the above-mentioned theory, demonstrate higher levels of learning achievement. The results include the following data on the four student samples: (BIOL. 1001, N=10, 89.35 [+ or -] 10.28, 71-100); (BIOL. 1201, N=3, 88.33 [+ or -] 8.94, 78-93.5); (BIOL. 1002, N=15, 78.13 [+ or -] 8.72, 70-92); (BIOL. 1001, N=15, 84.93 [+ or -] 5.08, 80-98.5). This paper will discuss more implications of teaching biology to adult learners.
Chauvin, J. V. and J. Aucoin. NiSU. Bayou water analysis--Incorporating a relevant, real world analytical problem into the quantitative analysis lab. Traditional quantitative analysis lab courses provide excellent training in the techniques and practices of analytical chemistry. However, most experiments involve the analysis of Thorn Smith unknowns which are the antithesis of "real world" samples. In an effort to spark student interest, provide the opportunity to experience field testing and improve student learning, a bayou water analysis module has been developed and implemented during the Fall 1998 semester. The students, working in co-operative teams, sampled and analyzed fresh water samples collected from Bayou Lafourche. Texas Instruments--Calculator Based Laboratory (TI-CBL) and TI 83 systems with Vernier probes were used to determine the temperature, conductivity, and pH of the water samples. This work is an extension of a study conducted by high school teachers who participated in the Summer 1998 LaSIP project. Seasonal variation accounted for the differences observed and the overall water quality is good.
Darbeau, R. and J. Vallee. McSU. Computer-aided visualization of organic chemistry. The acquisition of a computer resource room and modem instrumentation has dramatically altered students' chemistry experiences, particularly in organic courses. They visualize mechanisms practice nomenclature, and become familiar with IR and NMR spectroscopy through the use of simulated modules and exercises on the Internet. They become familiar with IR and GC instruments through the routine use of computer-interfaced instrumentation. Professional lab reports are required and structures are drawn with ChemDraw. Several mobile carts with computers and one with a presentation system are available for lecture sessions. The acquisition of SpartanPlus will allow molecular modeling to be incorporated into the curriculum.
Landry, A.A. and G.V. Lo. NiSU. A Java applet for modeling chemical kinetics.--The emergence of the Internet and the "write once, run anywhere" philosophy of the Java language present an opportunity to maximize student access to educational programs. A program for investigating reaction mechanisms will be described. The program, implemented as a Java applet that runs under Netscape Navigator or Microsoft Internet Explorer, solves simultaneous differential rate equations using Bulirsch and Stoer's Rational Extrapolation Method. Classroom applications, such as investigations of the validity of the steady-state approximation and the initial rates method will be presented.
Lo, G. V. NiSU. Online homework for chemistry.--A survey of several implementations of chemistry testing via the Internet will be presented. Since potential academic dishonesty cannot be eliminated with remote testing, student use of these systems is best treated as homework or extra credit assignments. The advantages over regular paper assignments wilt be discussed.
Manivannan, K. SLU. M.K. Ballay. Denham Springs High School. D.E. Meltzer. Iowa State University. Use of interactive multiple representations in promoting student understanding of physics in active learning environments.--Different representations of knowledge such as verbal, pictorial, graphical and mathematical/symbolic may not be equally effective in communicating a particular concept (D.E. Meltzer. 1996. Comparative effectiveness of conceptual learning with various representational modes. AAPT Announcer 26(4):46). Presently, we are using activities in which a particular problem or concept is presented in several different representations. These are then "dissected" into several linked conceptual and numerical components to develop multiple-choice questions for flash-card use (D. E. Meltzer and K. Manivannan. 1996. Promoting interactivity in physics lecture classes. Phys. Teach. 34:72). We present examples to demonstrate the effectiveness of this approach.
Pugh, A. and F. Groves. NLU. A comprehensive program in elementary science methods.--The elementary science method's class at Northeast Louisiana University is taught in a BLOCK with 3 other method's classes during the first semester of a student's senior year. The class meets 3 hours per week and implements both hands-on experiences as well as lectures pertaining to pedagogy. Outside projects for the class include role-plays for planet elections, animal picture collections, shoebox experiments, partner experiments, and computer software evaluations. Students are on campus for the first nine weeks of the semester to attend the methods' classes.
Robertson, M.J. SLU. Internet delivery of a consumer chemistry course: An Instructor's perspective.--A survey course in chemistry, Chemistry for the Consumer, was targeted for transformation into an on-line course as part of a model distance learning initiative. This survey course is traditionally taught in a large lecture setting. In the online version of the course, a student attends class in an Internet classroom one night per week on her or his own computer. Lectures are delivered via synchronous chat and HTML slides, and students complete several short quizzes during each lecture period. In addition, the students submit assignments each week via e-mail; some portions of the assignments are based on the WWW. Pedagogical elements not typically attainable in the traditional lecture course are gained by the on-line delivery, but some other elements are lost. The instructor's perspective of teaching this on-line course, as compared to the traditional lecture course, will be presented.
Suits J.P. and Courville, A. McSU. Effects of multimedia learning upon chemistry achievement.--In this paper we describe the effects of a multimedia learning module upon the problem-solving achievement skills of students in first semester general chemistry. This module was designed to help students develop two sets of skills: visualization skills and computational problem-solving skills. The simultaneous development of these skills allows students the opportunity to experience a direct connection between a chemical principle and its corresponding chemical phenomenon. When this connection is made within the context of real world applications, students should be more involved in learning the material, and thus they should develop both sets of skills. Results indicated that one module enhanced one set but not the other one.
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|Publication:||The Proceedings of the Louisiana Academy of Sciences|
|Date:||Jan 1, 1999|
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