Sigma Xi and Office of Research

Sigma Xi
and
Office of Research
Student Poster Symposium
Abstracts
University of Mississippi
Triplett Alumni Center
April 2, 2003
The University of Mississippi
Chapter of Sigma Xi
And
University of Mississippi Office of Research
Student Poster Symposium
April 2, 2003
Triplett Alumni Center
University of Mississippi
Schedule of events:
1 - 2 PM - Poster set up
2 - 4 PM - Poster judging
4 –5 PM - Keynote address: Dr. Lee Riedinger
6:30 PM - Poster Awards Ceremony
2003-01-A
EFFECTS OF FLUOXETINE ON REPRODUCTIVE AND BIOCHEMICAL RESPONSES IN
JAPANESE MEDAKA.
James Weston1,3 , Duane B. Huggett1 , Christy M. Foran4 , Bryan W. Brooks 5 , Marc Slattery1,2 . The
University of Mississippi, 1 ETRP, 2 Dept. of Pharmacognosy, 3 Dept. of Biology, University, MS 38677,
4
West Virginia University, Dept. of Biology, Morgantown, WV 26506-6057, 5 University of North Texas,
Dept. of Biological Sciences, Denton, TX 76203.
The occurrence of pharmaceuticals in municipal wastewater has recently received considerable attention.
However, the potential aquatic impacts are largely unknown due to a lack of relevant data. Recently
fluoxetine, the active ingredient in a commonly prescribed antidepressant, was identified in municipal
wastewater effluent from the United States. Fluoxetine inhibits the reuptake of serotonin (5-HT) in the
pre-synaptic nerve cleft of mammals. 5-HT is found in many aquatic animal taxa and acts upon
physiological systems: developmental, reproductive, neurological and others. In aquatic vertebrates it has
been demonstrated that serotonin effects gonadotropin releasing hormone in the hypothalamus-pituitarygonadal axis. To assess potential fluoxetine mediated neuroendocrine interactions in aquatic vertebrates
Japanese medaka (Oryzias latipes) were exposed for 28 days (14 days pre-reproductive and 14 days
reproductive) to aqueous nominal concentrations of fluoxetine (0, 0.1, 0.5, 1 and 5 µg/L). Three groups of
endpoints were evaluated: reproductive, somatic and biochemical. There were no statistical differences
between treatment levels within reproductive and somatic endpoints evaluated (one-way ANOVA or
Kruskal-Wallis test). Female plasma estradiol concentration was the only biochemical endpoint with a
statistical difference (p = 0.014; one-way ANOVA with Fisher’s PLSD post hoc test). The 0.1µg/L level
was statistically higher than the control (p = 0.01) and the 0.5 µg/L level was elevated relative to the
control though not significantly (p = 0.054). In this study fluoxetine did not significantly affect endpoints
evaluated, except female plasma estradiol. Based on the current study’s experimental design we were
unable to detect any significant reproductive risks to Japanese medaka. Future experimental
considerations should include different aquatic vertebrate models due to the potential for varying
sensitivity to fluoxetine or response to 5-HT.
2003-02-A
16S rRNA CHARACTERIZATION OF INDOLE-3-ACETIC ACID-PRODUCING FRESHWATER
WETLAND RHIZOBACTERIA
Dinesh Talreja and Lidija Halda-Alija Department of Biology, University of Mississippi, University, MS
38677
Production of indole -3-acetic acid (IAA), plant hormone, a key physiological feature of heterotrophic and
enteric rhizosphere assemblages associated with freshwater macrophyte Juncus effusus L. was examined
using classical microbiological methods over a period of three years. The cultivated enteric bacteria as
determined on MacConkey agar were an average 3.2 x 103 CFU g-1 dry soil in the vegetated sediments
as compared to 3.9 x 101 CFU g-1 dry soil in the unvegetated sediments. Our results indicate that the
number of enteric bacteria was significantly higher (p<0.05) in vegetated sediments as compared to
unvegetated sediments which was due to the rhizosphere effect (R/S = 82.1). Interestingly, heterotrophic
bacteria produced IAA even when tryptophan was not added to the medium. 16SrRNA sequencing
assigned one of the bacteria to Aeromonas spp. The sequence was analyzed by using the algorithms
BLAST and ClustalX. Phylogeny was assessed using PAUP* 4.0 The NJ tree indicated that sequence of
Aeromonas MS F70 is homologous to all 4 subspecies of Aeromonas salmonicida. Aeromonas MS F70
produced 55.2mg/L IAA in presence of 100µg/mL tryptophan indicating tryptophan is a precursor for
IAA in aeromonads. Indole -3-Decarboxylase (IPDC) is a key enzyme in IAA synthesis in enteric bacteria.
This is a first evidence of IAA production in Aeromonas spp. Currently we are developing primers for
synthesis of decarboxylase gene in Aeromonas spp.
2003-03-G
FUNCTIONAL EFFECTS OF EPHEDRINE ANALOGS ON BETA-ADRENERGIC RECEPTORS IN
LNCAP CELLS.
R.D. Salas1, 2 , R.Nagmani1 , I.A.Khan1 , M.M. Salazar-Bookaman2 and D.R. Feller1 . 1Departments of
Pharmacology and Pharmacognosy, Natural Center for Natural Products Research, RIPS, University of
Mississippi, University, MS, and 2 Department of Pharmacology, Central University of Venezuela,
Caracas-Venezuela.
Little information exists on the evaluation of the functional effects of ephedrine alkaloids on adrenergic
receptors (ARs) present in prostate cells. The functional effects of ephedrine alkaloids were examined in a
human prostate cancer cell line (LNCaP) using a 6 CRE-luciferase (luc) reporter gene assay. Cells were
electroporated with this CRE-luc gene plasmid and incubated in a 96-well microtiter plate for 24 hours,
and exposed to ephedrine analogs for 4 hours prior to measurement of luc activity. For antagonist studies,
cells were preincubated with drugs (10-7 to 10-4 M) 30 min prior to addition of (-) -isoproterenol. pHydroxyephedrine produced a small change in luciferase activity that was equal to 12% of the maximal
isoproterenol response. Stereoisomers of ephedrine and the 1R,2S-isomers of norephedrine and Nmethylephedrine were inactive as agonists, and the 1R,2S-isomers of ephedrine, norephedrine, phydroxyephedrine and N-methylephedrine were able to block responses to (-)-isoproterenol and
fenoterol; having antagonist potencies (KB values, mM) of 1R,2S-ephedrine (2.5 & 0.21) = 1R,2Snorephedrine (3.2 & 0.37) > 1R,2S-p-hydroxyephedrine (5.5 & 0.50) > 1R,2S-N-methyl-ephedrine (39 &
11), respectively. Thus, ephedrine alkaloids of the 1R, 2S configuration are antagonists of beta-ARs in
LNCaP cells, and they may represent an approach to interfere with catecholamine-mediated growth
promoting and cell differentiating effects in prostate cancer cells. [NCCAM Grant No. R21 AT00510 &
USDA ARS Agreement No. 58-6408-2-0009].
2003-04-A
KIN RECOGNITION IN CAPTIVE WILD TURKEYS (MELEAGRIS GALLOPAVO)
Leigh B. Truong and Richard Buchholz, Department of Biology, University of Mississippi, University,
MS 38677
Wild turkeys (Meleagris gallopavo) are a socially dynamic species that spends the majority of their
annual cycle in the company of other turkeys. Over 30 years ago, Watts and Stokes claimed that the social
interactions of wild turkey broods and adult males were mediated by kinship. Since then, many authors
have propagated the idea that male breeding behavior in turkeys is kin selected. Balph et al. challenged
the findings of Watts and Stokes on methodological grounds, and found that it was statistically
improbable for male coalitions to be composed only of siblings.
To examine if kinship mediates the social interactions of wild turkeys, I bred and raised turkeys in groups
of mixed parentage and allowed them to choose between a relative and non-relative. Specifically, I asked
if a) year-old turkeys could recognize their mothers from unrelated females, b) adult females
preferentially associated with sisters more than non-sisters, and c) turkey poults could distinguish siblings
from non-siblings. An association bias towards a relative indicated kin recognition. I found that year-old
turkeys spent a significant amount of time with their mothers (P = 0.029). Adult females spent a greater
proportion of their time with sisters (P = 0.042). Turkey poults associated with siblings more often than
non-siblings (P = 0.028). Though both Watts and Stokes and Balph et al. present compelling evidence for
kin and non-kin mediated behavior, my study supports Watts and Stokes’ initial observations. That is, kin
recognition appears to govern the social behavior of wild turkeys, and is mediated by genetically based
mechanisms. The benefits of kin discrimination for wild turkeys and the implications of kin recognition to
the evolution of social behavior will be discussed.
2003-05-G
IN-VIVO ANTI-INFLAMMATORY AND ANALGESIC EFFECTS OF SESQUITERPENE
LACTONES: PARTHENOLIDE AND ENHYDRIN
Matthew W. Feltenstein 1 , Wolfgang Schuehly 2,3 , Jason E. Warnick1 , Nikolaus H. Fischer2,3 , Kenneth J.
Sufka 1,3,4 . 1Department of Psychology, 2 Department of Pharmacognosy, 3 Research Institute of
Pharmaceutical Sciences, 4 Department of Pharmacology, University of Mississippi, University MS,
38677 USA
Sesquiterpene lactones are known to possess a variety of biological activities, including antiinflammatory activity. Two plants native to the southeastern United States, Magnolia grandiflora and
Polymnia uvedalia (Asteraceae), have been found to possess the sesquiterpene lactones parthenolide and
enhydrin, respectively. In this study, the anti-inflammatory and analgesic effects of the isolated lactones
from these plants were evaluated in a carrageenan inflammatory in vivo assay. Male Holtzman rats
received IP injections of either vehicle or drug probe (mg/kg: 5.0 indomethacin, 20.0
dihydroparthenolide, 5.0 and 20.0 parthenolide, and 5.0 and 20.0 enhydrin) and a 100ìl injection of 2.0%
carrageenan into the plantar surface of the right hindpaw. Thermal hyperalgesia (Hargreaves test) and
paw edema (via Plethysomometer) measures were recorded at four test intervals: baseline, 1, 2 and 4
hours post-carrageenan injection. Vehicle -treated animals exhibited a significant time-dependent
hyperalgesic and edema response that was greatest at the 4-hour test interval. Indomethacin significantly
attenuated the hyperalgesic response while 20.0 mg/kg parthenolide and 20.0 mg/kg enhydrin
significantly attenuated both measures. As expected, dihydroparthenolide was ineffective at reversing
carrageenan-induced inflammatory nociception. These findings suggest that parthenolide and enhydrin
may be useful in the treatment of inflammation and pain.
2003-06-I
PEER SOCIAL COMPETENCE AND THE STABILITY OF VICTIMIZATION
Browning, Christine¹, Cohen, Robert², and Warman Martin, Debbie³. ¹Department of Leadership and
Counselor Education, University of Mississippi, University, MS 38677, USA. ²Department of
Psychology, University of Memphis, Memphis, TN 38659, ³Department of Psychiatry, University of
Philadelphia, PA, 19104.
The goal of the present research was to identify social factors that may protect children who are victims of
peer aggression from continuing to be victims. Based on peer behavior nominations over a one-year
period, third through sixth grade children were classified into four Stability of Victimization Groups:
Never Victims, Stable Victims, Discontinued Victims, Became Victims. A variety of measures of social
competence were used including self, friendships, social standing, and peer nominations for social
behaviors. Children who were victims in the first year but not victims in the second year (Discontinued
Victims) had mutual friendships in the first year with children who themselves had lower victimization
scores than did the friends of children who continued to be victimized in the second year (Stable Victims).
In addition, children who were no longer victimized at Year 2 (Discontinued Victims) significantly
improved in self perceptions of social and global competence, in their social standing among peers, and in
peer attributions of withdrawn and rejected behaviors. These findings extend research on the buffering
effects of friendships by highlighting characteristics of friends (in this case victimization behaviors) that
are associated with these effects
2003-07-A
PATTERNS OF ANTIBIOTIC RESISTANCE IN FRESHWATER WETLAND ENTERIC BACTERIA
Moktan, S., Halda-Alija, L. and M. Jacob. University of Mississippi, University, MS 38677
In order to evaluate antibiotic resistance in freshwater wetland bacterial populations, sediment samples
were collected from the northern Mississippi wetlands. Strains of Enterobacteriaceae (representative of
the human and animal commensal flora) and other enteric bacteria were selected for antibiotic
susceptibility testing. Enteric bacteria were analyzed using classical microbiological methods, API20E,
fatty acid analyses, 16S RNA sequencing, and their susceptibility to a panel of antibiotics assessed using
NCCLS protocols. Based on 16S rRNA gene sequencing, we have found that rhizobacteria associated
with the freshwater wetland plant Juncus effusus L. express enormous phylogenetic diversity. The
sequences were analyzed by using the algorithms BLAST (National Center for Biotechnology
Information [http://www.ncbi.nlm.nih.gov]) and ClustalX. Phylogeny was assessed using PAUP 4.0
(Sinauer Associates, Inc.). The rate of acquired ampicillin resistance (< 50 ug/ml) was high for ampicillin
for 98 out of 137 (72%) bacteria tested. The rate of acquired resistance was low (>10 to 20ug/ml) for
kanamycin, tetracycline, and chloramphenicol for all strains tested. Out of these tested bacterial strains,
ten were selected for further susceptibility testing. MIC tests confirmed the rates of acquired antibiotic
resistance for ampicillin, kanamycin, chloramphenicol, and tetracycline. MBC values were in some cases
10 times higher compared to MIC values. Although enteric bacteria have a natural resistance toward
ampicillin, the rate of resistance suggests that resistance was acquired by gene transfer. The rate of
acquired resistance for kanamycin, tetracycline, and chloramphenicol suggests intrinsic antibiotic
resistance. Utilizing the distribution and antibiotic resistance of enteric bacteria in the environment as
warning of possible contamination and as index of water and soil/sediment quality deterioration will
significantly contributes to the long-term protection of human health and freshwater wetlands.
2003-08-C
INTERACTION OF CAMP TOTHECIN WITH A NICKED DNA DUPLEX.
Rachel A. Hutchins and David E. Graves. Dept. of Chemistry and Biochemistry, University of
Mississippi, University, MS 38677.
The cytotoxicity of the anticancer drug camptothecin (CPT) has been attributed to the accumulation of
single-strand DNA breaks mediated by the enzyme topoisomerase I. Experimental models have proposed
that the binding of topoisomerase I to double -stranded DNA is a necessary precursor for CPT binding;
CPT interacts with the enzyme and DNA in this cleavable complex and prevents the religation of the
single-stranded nick generated by topoisomerase I. The present study ascertains the ability of CPT to
bind to a nicked DNA duplex in the absence of topoisomerase I. Three oligonucleotides, a 8mer, 9mer,
and 17mer, were annealed to generate a 17mer duplex with a single -strand nick. The interaction of CPT
with the nicked duplex was assessed using UV-visible spectrophotometry. The significant hypochromic
shift in the drug spectrum observed in the presence of nicked duplex suggests that CPT does bind nicked
DNA. Comparisons of melting temperatures of the nicked 17mer duplex and n! ative 17mer duplex
indicated that the presence of a single nick decreases the Tm by 26ºC and thus destabilizes the helix. The
melting temperature of the nicked 17mer duplex was found to be unaffected by CPT binding.
Furthermore, the difference in molar absorptivity of free and bound CPT was significantly less than that
seen with classic intercalators. These findings suggest either a nonintercalative mode of binding or a low
affinity intercalative binding. This research is supported by a Graduate Research Fellowship of the
National Science Foundation and the Molecular Biophysics Division of the National Science Foundation,
MCB-0099217.
2003-09-B
FREEZE PELLETIZATION TECHNIQUE FOR THE PREPARATION OF ORAL IMMEDIATE AND
CONTROLLED RELEASE MATRIX PELLETS
Sreekhar Cheboyina and Christy M. Wyandt. Department of Pharmaceutics, School of Pharmacy,
University of Mississippi, Universit y, MS 38677
A simple and new technique of pelletization ‘Freeze Pelletization’ was developed to solidify molten solid
matrices into spherical pellets. In this technique, molten solid matrix is introduced into a column of liquid,
which is immiscible and inert with respect to the molten matrix. Due to high interfacial tension and
greater density molten solid matrix moves down in the column in the form of liquid droplets and gets
solidified into spherical pellets. Applications of this technique include immediate and controlled release
pellets in pharmaceuticals and as well as in fertilizers, agrochemicals, cosmetics and personal care
products. In this study pellets containing dexamethasone as a model drug were prepared by the freeze
pelletization technique. Immediate release pellets were prepared with hydrophilic solids and controlled
release pellets were prepared using a mixture of hydrophilic and hydrophobic solids. Pellets were
spherical in shape and found to be non-porous. Particle size analysis showed that pellets were in a narrow
size range with an average diameter of 2.15mm. Pellet properties were acceptable with drug loading up to
25%w/w. Release studies were conducted in 900 ml of nano pure water using USP apparatus I at a
rotation speed of 100 rpm. Samples were taken at predetermined time intervals and amount of drug
released was analyzed by UV- VIS spectrophotometer. Drug release from immediate release pellets was
100% in less than 30 minutes and prolonged drug release for several hours was observed for controlled
release pellets.
2003-10-G
PREFORMULATION STUDIES OF AN 8-AMINOQUINOLINE DERIVATIVE - A NOVEL
ANTIMALARIAL DRUG.
A. K. Dutta 1 , B. A. Avery1,2 , C. M. Wyandt1,2 1 Laboratory of Advanced Pharmaceutics, Department of
Pharmaceutics, 2 National Center for Natural Products Research, University, MS 38677
Purpose. To study the physicochemical characteristics of an 8-aminoquinoline derivative, a novel antimalarial drug, in order to provide adequate data for the development of an appropriate oral formulation.
Methods. A stability-indicating HPLC method for the determination and quantitation of the drug was
developed and validated. The various studies performed were: solid-state characterization including
hygroscopicity and thermal analysis using differential scanning calorimetry and thermogravimetric
analysis; pKa by potentiometric method; determination of octanol-water partition coefficient and
estimation apparent partition coefficient by HPLC and molecular modeling; pH solubility; solubility in
various cosolvent-water mixtures and stability of the drug in solution as a function of pH. Results. The
compound was detected at 254 nm using 71:29:0.065 methanol:water:TFA with C18(2) Luna column.
The amount of water adsorbed by the solid drug increased with increasing relative humidity up to 10.32%
at 90% RH. The compound was not found to be crystalline as no melting endotherms were observed. The
pKa was determined to be 8.3. The octanol-water partition coefficient, Log P was found to be 2.25 and
Log P estimates from the HPLC and molecular modeling methods are 3.85 and 3.82 respectively. The
solubility of the compound decreased with increasing pH. The solubility increased with increasing
concentration of cosolvent. It was found that the solubilizing capacity of cosolvent mixtures was ethanol
> propyleneglycol > polyethylene glycol 400 > dimethyl sulfoxide. The decomposition kinetics of the
drug at pH 3 was found to follow a 1st order model with a rate constant of 0.0096 day-1. Conclusion. The
test compound was found to be highly lipophilic and sparingly soluble in the pH range of interest. The
solubility of the drug can be significantly increased by the use of cosolvents which would enhance the
oral bioavailability of the drug. The studies performed here provide information useful for further preclinical studies.
2003-11-C
PHYTOCHEMICAL AND BIOLOGICAL INVESTIGATION OF ZANTHOXYLUM
MONOPHYLLUM (LAM.) P. WILSON (RUTACEAE)
Laura C. Johansmann1 , Charles L. Burandt2 , and Samir A. Ross1,2 *. 1Department of Pharmacognosy,
2
National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of
Pharmacy, The University of Mississippi, University, MS 38677, U.S.A. *Corresponding author.
The bright yellow bark of the Venezuelan tree Zanthoxylum monophyllum (Lam.) P. Wilson (Rutaceae)
is used in folk medicine to treat eye infections. Other Zanthoxylum species are used medicinally for
toothache, colic, rheumatism, typhoid-type diseases, and as a local anesthetic. In the present study, eleven
compounds were isolated and identified. Out of these, six were previously unreported compounds: the
alkaloids chelerythrine acetonate (1), norchelerythrine (2), bis(dihyrochelerythrinyl) ether (3), and 6ethoxydihydrochelerythrine (4), the coumarin marmesin (5), and the ester dodecyl caffeate (6). Previously
reported compounds isolated were the alkaloid salts berberine and chelerythrine, the lignan asarinin, the
triterpene lupeol, and sucrose. The structures were determined using NMR and MS techniques and by
comparison with published data. Compound 1 exhibited slight antiprotozoal activity. Compounds 3 and 4
exhibited antimicrobial activity against A. fumigatus ATCC 90906 comparable to Amphotericin B.
2003-12-B
ALKYLATION AND CYCLIZATION REACTIONS OF DIAZOKETONES: SYNTHESIS OF
SUBSTITUTED AZETIDINES
Lindsay D. Odom, John M. Rimoldi, and Aaron B. Beeler. Department of Medicinal Chemistry,
University of Mississippi, Laboratory for Applied Drug Design and Synthesis, University, MS 38677.
Azetidines are an intriguing class of heterocyclic compounds that have been shown to exhibit a wide
range of biological activities, including antihypertensive, anti-inflammatory, and anticancer activities.
We have utilized a catalytic rhodium (II) mediated cyclization procedure to construct differentially
protected chiral azetidines from N-Boc-L-serine in 5 steps (25% yield overall). In order to prepare
congested azetidines containing substituents at all ring positions, we required alkylated diazoketones prior
to the metal-catalyzed cyclization reaction. We will report the synthesis and reactivity of alkylated
diazoketones.
2003-13-C
DEFINING DOMAIN BOUNDARIES IN EPITHELIAL CADHERIN
Heather A. Levanduski, Nicole A. Housley, Tionanatasha Newell, and Susan Pedigo. Department of
Chemistry and Biochemistry. University of Mississippi, Coulter Hall, University, MS 38677
Cadherins are calcium-dependent cell adhesion proteins. They are a single polypeptide chain with
independently folded extracellular domains. Calcium binds at the interface between the extracellular
domains, influencing their stability and dimerization. In order to understand the role of calcium, we are
creating a family of clones of the two most extracellular domains of mouse epithelial cadherin. We are
inserting stop codons in several critical regions thereby truncating the structure such that the linker
regions between the domains are either included or omitted. Primers have been designed that engineer a
stop codon and a Hind III site at the 3¡¯ends of the gene as dictated by the new domain boundaries. In
conjunction with a primer complimentary to the 5¡¯end that has a convenient Nde I site, we report results
of PCR, restriction digestion and ligation to create a new family of clones. Analysis of protein products
will be reported.
2003-14-C
PURIFICATION AND SPECTRAL CHARACTERIZATION OF DOMAINS 1 AND 2 OF
EPITHELIAL CADHERIN
Alka Prasad, Susan Pedigo, Huaying Zhao, Heather Levanduski, J. Matthew Rutherford and Nicole
Housley. Department of Chemistry and Biochemistry, University of Mississippi, Coulter Hall,
University, Mississippi 38677.
Cadherins are calcium-dependent cell adhesion proteins. They are a single polypeptide chain with
between 3 and 7 independently folded extracellular domains. Calcium binds at the interface between
these extracellular domains and changes their relative orientation. The protein is then activated to
participate in parallel dimerization with an identical cadherin on the same cell surface. Cadherin dimers
interact in an antiparallel fashion with cadherin dimers from a neighboring cell surface to form tetramers,
thereby adhering two cells together. Our laboratory is interested in understanding the energetics of the
calcium linkage in dimer and tetramer formation. Fortunately, we can study the stability and calcium
binding properties of the extracellular domains separated from the rest of the molecule since they fold
independently and are soluble. We report: (1) Creation of a family of clones that explore the importance
of the choice of domain boundaries, (2) Purification of a two domain protein (extracellular domains 1 and
2) using anion exchange, size exclusion and affinity chromatography, (3) Preliminary calcium-dependent
proteolytic footprinting studies with chymotrypsin, and (4) Fluorescence and CD spectra of the native
protein in the presence and absence of calcium
2003-15-B
4-PENTADEUTEROPHENYLETHYNYLACETOPHENONE
Shavonne Sicher, Aimee Zaiontz, and Daniell Mattern
Department of Chemistry and Biochemistry
University of Mississippi
University MS 38677
To complete 13C-NMR assignments in phenylethynylacetopheone (acetyltolan) for a 13C substituent
effect study, two signals had to be assigned that were almost coincident. One was in the phenyl ring and
the other in the acetophenone ring. By using palladium-catalyzed Sonogashira chemistry with d5bromobenzene, we prepared phenylethynylacetopheone with the phenyl ring deuterated. Each deuterated
carbon split into a triplet and changed chemical shift and intensity, thereby distinguishing the two close
signals.
2003-16-B
AB INITIO STUDY OF THE CONFORMATIONAL PREFERENCES OF TYROSINE
Lisa C. Fedoroff, Brian W. Hopkins, and Gregory S. Tschumper.
Department of Chemistry and Biochemistry, University of Mississippi
Tyrosine is an important building block of protein structure. Its conformational preferences are therefore
of great interest both as an individual molecule and as part of a polypeptide structure. In this study, the
potential energy surface of the neutral molecule of tyrosine was analyzed with respect to the five torsional
angles shown. A series of one-dimensional and two-dimensional torsional angle scans were used to locate
the possible minima. The scans identified 64 possible minima. These structures were further refined and
characterized using the RHF and B3LYP methods and the [6-31++ G(d,p)] basis set.
2003-17-B
SOLID-STATE CHARACTERIZATION OF HOT-MELT EXTRUDED FILMS CONTAINING
CLOTRIMAZOLE
S. Prodduturi1 , M. A. Repka 2 , S. P. Stodghill3 . 1 Department of Pharmaceutics, School of Pharmacy,
2
Department of Pharmaceutics, National Center for Natural Products Research, University, MS 38677,
3
Laboratory for Advanced Pharmaceutics, Department of Pharmaceutics, School of Pharmacy, University,
MS 38677
Purpose. To produce and characterize hot-melt extruded polymeric films(solid dispersions) containing
clotrimazole(CT), hydroxypropyl cellulose (HPC), and poly(ethylene oxide) (PEO), to investigate the
effect of PEO on the solid state of the drug within these films and to explore DSC as a pre-formulation
tool to predict the state of the drug within the films prior to extrusion. Methods. Hot-melt extruded
(HME) films containing CT and various percentages of PEO were characterized using a Perkin Elmer
Pyris -1 Differential Scanning Calorimeter (DSC) with Pyris manager software and Wide-angled X-ray
diffraction (WAXRD). The effect of PEO on the solid state of the drug within these films was evaluated
by studying physical mixtures with CT and various percentages of PEO. Results. DSC and WAXRD
studies of the physical mixtures demonstrated that CT exhibited crystalline solid-state characteristics at a
critical PEO concentration. Conclusion. The CT incorporated in the HME films was determined to be in a
solid dispersion state. However, DSC studies suggest that crystallinity within these systems is a function
of PEO concentration due to the solubility of CT within the polymer. DSC is a valuable preformulation
tool, which may be used not only to characterize, but also to predict drug crystallinity within hot-melt
extruded systems.
2003-18-C
FOLDING AND ASSEMBLY OF LAMBDA CRO REPRESSOR DIMERS ARE KINETICALLY
LIMITED BY PROLINE ISOMERIZATION
W. John Satumba* and Michael C. Mossing Department of Chemistry and Biochemistry, University of
Mississippi, University, MS 38677
The folding and assembly kinetics of Cro dimers are dominated by slow isomerization of peptidyl prolyl
bonds in the dimer interface. CD and fluorescence were used to monitor unfolding and refolding of Cro
and selected variants. CD reported on loss and formation of helical structure. Fluorescence of a unique
tryptophan residue (in CroF58W and an engineered monomer CroK56 [DGEVK]F58W) is sensitive to
the isomeric configuration of the x-proline bonds in the sequence K56-P57-W58-P59. Fluorescence
Resonance Energy Transfer (FRET) between AEDANS and Fluorescein attached to separate subunits via
a unique cysteine in CroY26C reports on dimerization. Equilibrium unfolding of CroF58W by CD and
fluorescence shows that both probes track the same transition. Unfolding shows a burst phase that is
complete in the 5ms deadtime of stopped flow experiments and a slow phase (Ċ=50s) with a small
amplitude change in CD and a large increase in Trp fluorescence. Refolding also shows a burst and a
slow phase (Ċ=170s). The slow phase displays characteristics of proline isomerization including an
activation energy of 20kcal/mol and the ability to be accelerated by a peptidyl prolyl isomerase, SlyD.
More than 70% of the native CD signal is present initially for Cro and the single Trp variant CroF58W.
Even though 70% of secondary structure is attained in the deadtime, FRET refolding experiments show
an energy transfer signal that is only 25% of the native FRET signal. This suggests that a signif icant
population of the folded species are monomeric. A comparison of the expected proline isomer
distribution and the CD and FRET data presented above suggests that subunits with x-proline bonds in the
non-native configuration are competent to fold but at least one native proline isomeric configuration is
required for dimerization.
2003-19-A
FLUORESCENCE MICROSCOPY AND PROTEIN ASSAY TECHNIQUES TO EXPLAIN ENERGY
INTEGRATION OF METHANOGENIC REMEDIATION OF WASTE
Sulabh Koolwal1 Aarti Gidh1 , Clint Williford1 and Al Mikell2
1
Department of Chemical Engineering, 2 Department of Biology University of Mississippi, University, MS
38677.
Production of ethanol (major component of E85) by biomass fermentation is proving to be an extremely
environment friendly and economical option. One of the major by-products for this process is acetic acid.
Treating an acetic acid laden wastewater (5gm/L of acetic acid per 25gm/L of ethanol produced) with
such high BOD is an expensive option. Treatment also eliminates a valuable carbon source. Another
option is to study the anaerobic digestion efficiencies during the methanogenic digestion of the acetic acid
laden wastewaters to produce methane, which can then be used as a fuel within the facility. Batch reactors
(500 ml) fitted with pressure gauges and a valve and septum arrangement were used for inoculation and
incubation. Purging the reactors with nitrogen provided an oxygen free environment. Pressure change was
monitored and gas composition analyzed using a gas chromatograph (TCD) at regular time intervals. This
data was then used to calculate methane production rate. Fluorescence microscopy was used to obtain a
bacterial cell count in terms of number of cells per ml of sample. Results show that 32oC was far superior
for methanogenic growth than 45oC. Also for the two feed (acetate) compositions of 50 mM and 250
mM, the production profiles of methane (mol/L) vs nutrient composition (NH4Cl) show reverse trends.
Complementary trends as to the production of carbon dioxide can be used to explain this opposing effect.
Residence time also seemed to change the trend. NH4Cl concentration affects, acetate-utilizing
methanogens beneficially, but at the same time slightly inhibits CO2 utilizing methanogens. High carbon
content can counter this inhibition. Fluorescence microscopy and protein assay techniques were used to
confirm this explanation by linking bacterial growth to methane production.
2003-20-C
EQUILIBRIUM DIMERIZATION AND SUBUNIT EXCHANGE KINETICS OF CRO REPRESSOR
VARIANTS BY FLUORESCENCE RESONANCE ENERGY TRANSFER
Haifeng Jia, Gene L. Bidwell, Michael C. Mossing; Department of Chemistry and Biochemistry,
University of Mississippi, University, MS 38677
Cro is a repressor that binds to DNA as a dimer. Exchange of subunits between dimers can be monitored
by Fluorescence Resonance Energy Transfer (FRET). Since F58 is a key residue in the P57-F58-P59
cluster that anchors the dimer interface, here we compare the dimerization behavior of W58 and F58
proteins separately using the single mutant Cro Y26C and double mutant Cro Y26C F58W. In each case
the single cysteine 26 was covalently modified either with Iodoacetamidoaedans (IAEDANS) or 5iodoacetamido-fluorescein (IAF). A subunit exchange experiment where pre-equilibrated native samples
of donor and acceptor were mixed, resulted in slow kinetics that were independent of protein
concentration but highly dependent on temperature. Mixing experiments show a substantial decrease in
the exchange rate for the F58W mutation, kobs is 0.02s-1 for native Cro Y26C dimer and 0.001s-1 for
Cro Y26C F58W dimer. The increase in the exchange rate with temperature in the range of 25°C to 40°C
for the native Cro dimer yields a large activation energy of 28 Kcal/mol. Equilibrium measurements of
dimerization took advantage of the large difference in fluorescence intensity of IAF acceptors and
IAEDANS donors. A trace amount of acceptor was titrated by excess donor subunits over a large range.
The dimer dissociation equilibrium constant (Kd) determined as described for Cro Y26C is 2 ± 1 microM
and for Cro-F58W is 0.3 ± 0.2 microM. The F58W mutation results in both a slower exchange rate and
tighter association of subunits in the dimer.
2003-21-B
SYNTHESIS OF NOVEL AZETIDINES AS POTENTIAL PKC INHIBITORS: SOLUTION AND
SOLID-PHASE APPROACHES
Young Kim and John M. Rimoldi (Medicinal Chemistry)
The azetidine ring system represents an unusual substructure of several biologically relevant classes of
drugs, and these pharmacophores have been identified in several natural products, comprising significant
biological activities. We report the synthesis of differentially protected azetidines from readily available
L- and D-serine, in both solution and solid-phase synthetic protocols. A 50-member library of novel
azetidines funtionalized at C-2 and C-3 have been prepared using a solid-phase protocol.
2003-22-F
THE EFFECTS OF CHARGE AND ELECTROSTATIC POTENTIAL ON LIGHTNING
PROPAGATION
L. M. Coleman1 , M. Stolzenburg1 , T. C. Marshall1 , P. R. Krehbiel2 , R. J. Thomas2 , W. Rison2 , and T.
Hamlin 2 . 1 Department of Physics and Astronomy, University of Mississippi, University, MS.
2
Geophysical Research Center, New Mexico Institute of Mining and Technology, Socorro, NM.
Three-dimensional lightning mapping observations are compared to cloud charge structures and electric
potential profiles inferred from balloon soundings of electric field in New Mexico mountain
thunderstorms. The comparisons consistently show good agreement between the altitudes of horizontal
lightning channels and the altitudes of electric potential extrema or wells. Lightning flashes appear to
deposit charge of opposite polarity in relatively localized volumes within the preexisting lower positive,
midlevel negative, and upper positive charge regions associated with the potential wells. The net effect of
recurring lightning charge deposition at the approximate levels of potential extrema is to increase the
complexity in the observed storm charge structure. The midlevel breakdown of both normal intracloud
flashes and negative cloud-to-ground flashes is observed to be segregated by flash type into the upper and
lower parts of the deep potential well associated with the midlevel negative charge. The segregation is
consistent with perturbations observed in the bottom of the negative potential well due to embedded
positive charge that was probably deposited by earlier flashes. It is also consistent with an expected
tendency for vertical breakdown to begin branching horizontally before reaching the local potential
minimum. The joint observations reconcile the apparent dichotomy between the complex charge
structures often inferred from balloon soundings through storms and the simpler structures often inferred
from lightning measurements.
2003-23-F
DIFFUSION AS A RATE LIMITING FACTOR ON THE EVOLUTION OF STRONTIUM ISOTOPE
RATIOS IN FRACTURED ROCK
E. G. Johnson, R. M. Holt, and T. L. McLing
In recent years, several approaches have been developed to model the evolution of strontium isotope
ratios (87Sr/86Sr) in porous media. In fractured rock, however, diffusion limits the rates of reaction
between mobile water and mineral surfaces inside fracture-bounded blocks. Diffusion can limit transfer
of fluids with differing isotopic ratios between the mobile and immobile zones leading to longer
equilibration times. We develop a diffusion-based mathematical approach for modeling the evolution of
ratios that includes ion exchange and dissolution in fracture bounded blocks of multiple sizes. Traditiona l
models employing isotopic ratios with the advection-dispersion equation are unable to incorporate
diffusion because they are limited by the structure of their equation. Modeling the individual isotopic
species separately accounts for the effects of diffusion. The general governing equation is robust in that it
does not assume chemical equilibrium reactions. Special cases show the importance of diffusion-limited
mass transfer on the evolution of isotopes ratios in fractured rock.
2003-24-D
ELECTRONIC COOLING OF GENERIC TRANSMITTER/ RECEIVER MODULE USING HEAT
PIPES AND HEAT SINKS
Jaideep Bangal, Dr. Tyrus McCarty, Department of Mechanical Engineering, The University of
Mississippi, University, MS 38677
In recent years, the continuous increase of system power and decrease of available volume present,
temperature increase is becoming a critical area in the thermal management of electronics. In order to
maximize circuit performance and reliability, it is very much necessary to design and package electronic
assemblies to minimize heat generated and circuit temperature by employing adequate thermal
management methods. In this study the analysis involved the thermal management of an electronically
packaged system associated with a generic Transmitter/Receiver (T/R) module of a radar subsystem
utilizing heat pipe / heat sink technology for cooling the electronic components. The heat pipe, with an
extremely high effective thermal conductivity, transports heat away from the components to the heat sink
where it can be dissipated to the surrounding air. A computer simulation of the heat transfer in the generic
T/R module is performed to test the effectiveness of several specified designs using the software package
IcePak. One of the basic objectives of the present work is to predict the maximum temperature on the
power amplifier chip under steady state conditions. The simulation is carried out at different
environmental operating conditions and at different power settings for the power amplifier chip. The
results of this study provide several effective ways of insuring that the electronic components are operated
in a failure-safe environment.
2003-25-E
ELECTROMAGNETIC SCATTERING FROM A CHIRAL STRIP OF UNIFORM AND NONUNIFORM CHIRALITY DISTRIBUTION
Mohamed H. Al Sharkawy1 , Atef Z. Elsherbeni1 , and Samir F. Mahmoud2 .1 Center of Applied
Electromagnetic Systems Research (CASER), Department of Electrical Engineering, The University of
Mississippi, University, MS 38677. 2 Kuwait University, Department of Electric al and Computer
Engineering, Kuwait.
A semi-analytical solution is presented to the scattering of an incident electromagnetic plane wave on a
rectangular strip. The strip is simulated by parallel circular cylinders. The strip is illuminated by either a
TEz or a TMz incident plane wave. The solution is based on the application of the boundary conditions on
the surface of each cylinder in terms of the local coordinate system of each individual cylinder. The
scattered field from each cylinder is therefore represented in terms of the coordinate system of each
individual cylinder requiring the use of the additional theorem of Hankel and Bessel functions. The
application of the boundary conditions on the surface of all cylinders leads to an infinite matrix equation.
This matrix equation is truncated in order to allow for the numerical evaluation of the expansion
coefficients required for the calculations of the near and far field components. This technique is used to
predict the radar cross-section of strips composed of dielectric, conducting, and chiral material with
uniform or non-uniform chiral admittance distribution.
2003-26-E
STRIP MODE SAR SIMULATION FOR REMOTE SENSING APPLICATIONS
Edward Woo, Atef Z. Elsherbeni, and Charles E. Smith. Center of Applie d Electromagnetic Systems
Research (CASER), Department of Electrical Engineering, The University of Mississippi, University, MS
38677, USA
A software package for the simulation of earth/satellites relative positions and land coverage for remote
sensing applications is developed using the strip mode of synthetic aperture radar (SAR) system. This
package provides a visualization tool to help in the analysis and design of radar systems and the
techniques for collecting data for SAR systems. This simulation will also allow users to get a better
understanding of radar technology, global positioning systems, and basic remote sensing principles. Users
will be able to input orbital parameters (shape and position), satellite parameters (number, position and
speed), and illumination strip parameters (width and length). The distance between the satellites (while
moving around the earth) and earth coverage area are computed and displayed to the user in a window
along with a 3-dimensional dynamic view of the earth/satellites movements. The position of each satellite
in spherical coordinates is computed and displayed. The illumination beamwidth of the different satellite
antennas and the Strip mode SAR is adjustable for each satellite. A better understanding of the
earth/satellites dynamic relationship will assist in solving many of the technical problems of today’s
satellites global coverage systems.
2003-27-E
ANTENNA SIMULATION FROM INFINITESIMAL DIPOLES USING GENETIC ALGORITHMS
Taninder S. Sijher and Ahmed A. Kishk. Department of Electrical Engineering University of Mississippi,
University, MS 38677.
A method for the simulation of antennas or radiating sources from near-field measurements is presented.
The method is based on the substitution of an original radiating source with an equivalent set of
infinitesimal electric and magnetic dipoles that would produce the near field of original antenna and thus
the same far field. These equivalent sets of dipoles are generated using a rigorous optimization technique.
Here we have used Genetic Algorithm. The optimization method would determine the equivalent
infinitesimal dipoles, which produce the near field of the actual antenna. Once the equivalent dipole
positions and moments are determined, the far field can be obtained. Also the equivalent dipoles can be
used to replace some complicated antennas to simplify analysis of performance in a complex
environment. The method has been tested using synthetic data and the simulation results show the
viability and usefulness of the method. Future work will include simulation of antennas from computed
near fields. Also the method will be implemented with a commercial code for antenna design
optimization.
2003-28-E
RECTANGULAR SLOT ANTENNAS FOR PERSONAL WIRELESS COMMUNICATION SYSTEMS
Abdelnasser A. Eldek, Atef Z. Elsherbeni, Charles E. Smith and Kai-Fong Lee. Department of Electrical
Engineering, The University of Mississippi, University, MS 38677, USA
Antenna designs were achieved for wideband operation for personal communication systems by the use of
a coplanar patch-slot antenna fed by a coplanar waveguide. This design is easily tuned to operate at 2.45
and 5.75GHz, with up to 20% bandwidth. The patch dimensions are tuned to control the operating
frequency. Return loss, input impedance, radiation pattern, directivity, gain and efficiency of the proposed
designs are computed using the Agilent Technologies’ advanced design system (ADS) package. The
designed antennas showed wideband characteristics, with high efficiency, radiation pattern stability
across the operating band, and low directivity.
2003-29-D
THERMAL MANAGEMENT OF TRANSMITTER/RECEIVER (T/R) MODULE ARRAY USING
ICEPAK
Anil L. Jeswani and J. A. Roux, Department of Mechanical Engineering, University of Mississippi,
University, MS, 38677
Recent developments in electronic components have produced a significant increase in their dissipating
power and have led to the requirement for high heat flux dissipation with small allowable temperature
rise. Operating temperatures have a predominant effect on the life, reliability and performance of semiconductor devices. So thermal analysis is a significant issue in electronic packaging because excessive
temperatures reduce the useful life of the products. In the present work a base plate cooling scheme has
been proposed for cooling a generic transmitter/receiver (T/R) module using the CFD package Icepak.
The main objective of the present work is to estimate the maximum temperature on the power chip under
steady-state conditions. The analysis is carried out at different operating conditions such as varying
ambient (desert, mild, and artic) conditions, different flow rates of air in the cooling channel, and different
power settings on the power chip.
2003-30-H
NAÏVE BAYESIAN CLASSIFIER FOR MICROARRAY DATA
Arpad Kelemen1 , Hong Zhou1 , Pamela Lawhead1 , Yulan Liang2 . 1 Department of Computer and
Information Science University of Mississippi, University, MS 38677, USA. 2 Department of Social and
Preventive Medicine, The State University of New York at Buffalo, Buffalo, NY 14214 USA.
Comparing with more sophisticated classifiers, the naive Bayesian classifier greatly simplifies learning by
assuming that the attribute values are conditionally independent given the class. Although independence
is a strong assumption, in practice the naive Bayesian classifier often competes with other complex
classifiers and the naive Bayesian algorithm works well for classifying text document. In this paper, we
present our invented technique, called “attribute grouping” for data preprocessing. The naive Bayesian
algorithm is implemented for classifying multiple gene expression patterns from microarray experiments.
Results show that attribute grouping is very effective and that the naive Bayesian classifier becomes a
suitable classification method for microarray data when the attribute grouping is used.
2003-31-D
COMPUTER SIMULATION OF THE THERMAL MANAGEMENT OF MICROCHIPS VIA
HEAT/HEAT SINK TECHNOLOGY.
Nicholas Jeffries1 , Tyrus A. McCarty1 , and Derrick Brown2 . 1 Department of Mechanical Engineering
University of Mississippi, University MS 38677, USA. 2Department of Chemical Engineering University
of Mississippi, University MS 38677, USA.
The trend in packaging electronic systems has been to reduce the size of devices by placing more
functions in smaller packages to increase their performance. This has contributed to higher heat densities,
requiring that thermal management be given a high priority in the design cycle in order to maintain
system performance and reliability. In this study the analysis involved the thermal management of an
electronically packaged system associated with a radar subsystem. A computer simulation of the heat
transfer in the radar subsystem was performed to test the effectiveness of several specified design
conditions. A computational numerical technique was employed to solve the basic equations that
governed the physical processes occurring in the radar subsystem. This study focused on the utilization of
heat pipe/heat sink technology for cooling the electronic components associated with this subsystem. The
results of this study are vital because they provide several effective ways of insuring that the electronic
components are operated in a failure-safe environment.
2003-32-B
USING ADMICELLAR POLYMERIZATION TO FORM AN ULTRATHIN SILICONE RUBBER
FILM ON SILICA.
Sarah E. Gates, John H. O'Haver. Department of Chemical Engineering University of Mississippi,
University MS 38677, USA.
Admicellar polymerization, polymerization of monomers solubilized in surfactant aggregates adsorbed at
a solid/liquid interface (admicelles), has been examined as a means of modifying amorphous, precipitated
silica for use as a reinforcing-filler in rubber compounds. Admicellar polymerization can be thought of as
occurring in four steps, (I) surfactant adsorption/admicelle formation, (II) adsolubilization of monomer(s),
(III) polymerization and (IV) surfactant removal. To date this process has been accomplished via free
radical polymerization using thermal initiation and monomers that are typically contained in common
elastomers, i.e., styrene, butadiene, isoprene, and others. A commercially significant but chemically
different group of elastomers are silicone rubbers. Silicone compounds do not typically mix well with
hydrocarbon compounds nor with carbon fillers. Thus, the ability to make a reinforced silicone rubber is
commercially important. We are examining using admicellar polymerization to form in-situ a silicone
polymer in surfactant aggregates adsorbed on a nonporous silica surface. The research thus far has
focused on substrate selection and preparation, determining an appropriate reaction and selection of
monomers, development of the experimental plan, and determining appropriate analytical methods.
2003-33-F
A SYNTHESIS STUDY AND GIS DATABASE FOR BRIDGE CATHODIC PROTECTION
PROJECTS IN THE UNITED STATES
Kanok Boriboonsomsin. Department of Civil Engineering, University of Mississippi, University MS
38677, USA.
Highway bridges are the life-line of US economy and society. Environmentally induced stresses can
contribute to premature fracture of concrete structures and reduce service life significantly. These failures
occur at load stress levels considerably below design stresses and may threat human life. Estimate for
bridge maintenance and repair is $30-$50 million per year in Florida alone, most of which is probably
associated with corrosion of reinforcing bars. Cathodic Protection (CP) technology is a significant tool for
preserving bridges from corrosion problems. More than 500 bridges in North America apply CP
technology. The studies of CP design, material type (anode type), and application technique show that CP
technology is the most superior method for solving, or at least mitigating, corrosion problems. This paper
describes results of a synthesis study of CP technology applied to bridges including performance
evaluation and life-cycle costs. A geographic information system (GIS) database for bridge cathodic
protection proje cts, developed in this project, includes a total of 65 bridges. Most of them are located in
Florida near the sea. Among these 65 bridges, 20 have an impressed current system, another 36 have a
sacrificial anode system, 3 have both systems, and the rest have no type of CP system data at the time of
reporting. The portable cathodic protection technology will extend the life of bridges in harsh
environment, resulting in lower maintenance cost annually.
2003-34-D
TIME-RESOLVED, LOW-DIMENSIONAL ESTIMATION OF OPEN CAVITY FLOW
Nathan E. Murray, Lawrence S. Ukeiley, Jamie L. Whitten National Center for Physical Acoustics,
University of Mississippi, University MS 38677, USA.
In an effort to gain time-resolved data about the relationship between surface pressures and shear layer
velocities in an open cavity flow, a quadratic stochastic estimation (QSE) is formulated for multiple
predictor inputs to yield time-dependent results. Recent emphasis on cavity flow has focused on active
control of the unsteady pressures in the cavity for dynamic flow conditions. QSE is presented as a means
for obtaining the time-resolved data necessary for building a suitable active control. The formulation of
the QSE is developed by comparison to time-resolved data from a Navier-Stokes simulation of a Mach
1.5 flow over a cavity with a length to depth (L/D) ratio of 6. For the experimental phase of the study, the
author undertook the design and construction of a new low speed wind tunnel facility at the University of
Mississippi, National Center for Physical Acoustics. The QSE is applied to experimental data acquired in
the new facility through the use of particle image velocimetry (PIV). The experiment is carried out for a
Mach 0.17 flow over a cavity with L/D = 5.16. Application of the QSE to the experimental data shows
that the estimation is capable of producing time-resolved results that agree with expected cavity flow
mechanics.
2003-35-F
JOINTING AND ROCK WEDGES OBSERVED IN A CUT SLOPE NEAR FREDRICKTOWN,
MISSOURI
Thompson, William C. and Kuszmaul, Joel S., Department of Geology and Geological Engineering,
University of Mississippi, University, MS 38677.
The design of slopes in jointed rock requires that engineers consider whether rock wedges formed by two
or more joints can slide out of the slope face. To identify the number of unstable wedges information
must be gathered regarding the location, orientation, persistence, and length of discontinuities present
within the rock mass. This information was collected using a scan-line survey on a cut slope near
Fredericktown, Missouri. This stable cut slope allowed the inspection of the actual number of rock
wedges observed in the excavation. The number and size of each rock wedge in the excavation was
recorded to create a histogram of rock wedge occurrence within the slope. These observed wedges are
compared to a predictive tool that calculates the number and size of expected wedges in a rock slope
given information regarding joint set features. Joint set properties are interpreted for each set separately to
permit application of the predictive wedge analysis. In addition, histograms of the observed wedges and
potential wedges are identified for the readily recognizable joint set combinations. These histograms were
the principa l objective of this investigation as they permit comparison of the predictive tool to the actual
number of wedges observed in the slope for the most prominent wedge type. The observed number of
wedges is substantially lower than the predicted number, but the distribution of observed and predicted
sizes are similar.
2003-36-E
GRAPHICAL USER INTERFACE (GUI) AND ANALYSIS SOFWARE USING MATLAB AND
RELATED TOOLBOXES FOR HPIB DATA ACQUISITION AND PROCESSING
Brian T. McDaniel*, Charles E. Smith, , Ale xander B. Yakovlev , Atef Z. Elsherbeni, and Darko Kajfez,
The University of Mississippi, University, MS 38677-1848
This paper presents the software and hardware design and implementation of a user-friendly graphical
user interface (GUI) for data acquisition, analysis and presentation for use with instruments using the
HPIB/GPIB (IEEE 488) instrument control bus. The hardware used to demonstrate the data acquisition
and graphic display capabilities for this software is an HP8510C Network Analyzer or HP8530
Microwave Receiver with HPIB capability, a PC with a National Instruments NI-488.2 HPIB card and
corresponding drivers, and MATLAB with the related Instrument Control Toolbox. The design, setup and
implementation of the GUI data acquisition and presentation software is presented. The vector network
analyzers, used for this research development, offer a simple and accurate method for making electrical
vector and S-parameter measurements at high frequencies for determining network and circuit
performance. However, exporting the measured data to a file on disk, taking the disc to a PC, then
creating “command line” software programs to read the files can consume more time and effort than
making the desired measurements. Using the techniques and software developed, The University of
Mississippi has implemented an efficient, user-friendly environment for making RF/microwave
measurements or antenna pattern measurements and then transporting the measured data to a PC for
analysis and presentation with MATLAB in rectilinear plots, polar plots and Smith Charts formats.
Examples of the use and application of this HPIB-GUI software showing data acquisition and graphical
data display are also presented for S-parameter and antenna radiation pattern measurements.
2003-37-D
FOLLOW THE LINE: USING VISION IN AN AUTONOMOUS MOBILE ROBOT
Jie Tang, Dr. Pamela B. Lawhead Department of Computer and Information Science University of
Mississippi University, MS 38677, USA
The goal of this project is to build an autonomous mobile robot that is capable of following a line in
multiple environments. The configuration of the hardware system of robot and the environmental factors
will affect the ability of the robot to follow a line. Also different styles of lines have different effects on
the robot’s ability to follow a line. In this research project we have developed a solution to improve the
performance of the robot in multiple environments. The robot built for this project uses a laptop
computer, a Vision module, a Motor module, a Steering module and four sonar units. The laptop uses
Microsoft’s Windows 98. The robot was designed with a subsumptive architecture so that no single
module serves to control the entire robot. The vision module acquires data from a commonly available
web camera. The Motor module controls the motor of the robot. The Steering module controls the moving
directionality of the robot. The web camera is installed in the middle of the front hood of the robot. It
captures the data of a black line. The Control Center receives the data and processes it. The output is the
edge information of the line. This edge information serves as input to the direction detection module.
After analyzing it, the direction of the line is given. Then the control center sends a command to the
Motor module and Steering module, and the robot then follows the line. Critical to the entire system is its
final cost. The goal was to build a robot that could be used by other schools to teach subsumption and
autonomy in the design of a mobile robot. Therefore the system was built using a child’s toy car and other
commonly available equipment. The current development cost of the project is just under six thousand
dollars and well within the cost of replication by smaller schools.
2003-38-D
SHORT TERM AGING EFFECTS ON GLASS POLYESTER COMPOSITES
Rohit Joshi, Dr. James Vaughan, Dr. Ellen Lackey. Department of Mechanical Engineering University of
Mississippi, University of Mississippi, University MS 38677, USA
Polyester/glass pultruded composites have been examined to determine room temperature post-cure aging
effects on the mechanical properties of the composite. The intent of this study was to understand and
quantify the effects that room temperature storage time can have on composite properties. The pultruded
composites were purposefully manufactured with a wide range of initial degrees of cure as they exited
from the die to determine the effect of aging for varying initial degree of cure conditions. The properties
studied were Barcol hardness and short-beam strength. These properties were correlated with
measurements of the degree of cure of the composites over the aging period as determined from
differential scanning calorimetry. Property measurements were taken every twelve hours for one week
until results showed that little further changes were occurring, and then, for long-term comparison,
properties were measured six months later. Results show that composites that are not fully cured as they
exit the die exhibit significant aging effects over the first week of room temperature storage after
production. Results from this study can be used to validate mechanical property testing of recently
pultruded composites against properties of composites stored for lengthy times before use.
2003-39-G
PSYCHOLOGICAL STRESS DURING EXERCISE: CARDIORESPIRATORY AND HORMONAL
RESPONSES
H.E. Webb1, 2 , M.L. Weldy1 , E.C. Fabianke 1 , G.R. Orndorff1 , G.H. Kamimori3 , FACSM, E.O. Acevedo1 ,
FACSM. Division of Exercise Science1 , University of Mississippi, University, MS; Department of
Pharmacology2 , University of Mississippi, University, MS; Walter Reed Army Research Institute 3 ,
Washington, DC.
The influence of psychological states on physiological responses during exercise is of considerable
importance to the soldier, pilot, firefighter, police officer, athlete, and other individuals for whom the
efficiency of energy production is critical to job performance. Stress responses to physical and
psychological challenges are regulated by hormones that are released following activation of the
sympathoadrenal axis and the hypothalamo-pituitary-adrenocortical axis. Hormonal responses to the
combination of physical and psychological stress have not been examined. PURPOSE: This study
examined the cardiorespiratory responses of heart rate (HR), ventilation (VE ), respiratory rate (RR),
oxygen consumption (VO2 ), and respiratory exchange ratio (RER) and the hormonal responses of
epinephrine (Epi), norepinephrine (NE) and cortisol (CORT) to psychological and physical stress
combined. METHODS: Nine subjects performed a graded exercise test on a cycle ergometer to assess
maximal oxygen consumption (VO2max). Subsequently, each subject participated in two conditions. The
treatment condition was a ride at 60% of VO 2max while participating in a computerized psychological
stressor (stress condition; SC), whereas in the control condition subjects rode at the same intensity
without the psychological stressor (no stress condition; NSC). The NASA Task Load Index (NTLX) was
used to assess perceived physical and psychological load during each condition. These sessions were
counter-balanced between subjects. RESULTS: RMANOVA’s revealed significant interactions across
time for cardiorespiratory responses (HR, VE , and RR) between the NSC and the SC. Epi AUC was not
significantly different between the two conditions; however, NE AUC was significantly elevated in the
SC. Furthermore, cortisol AUC was also significantly elevated during the SC. NTLX scores demonstrated
that the subjects perceived overall workload to be higher in the SC. CONCLUSION: These results
demonstrate that psychological stress during exercise can elicit a stress response including the release of
hormones that have been linked to negative health consequences.
2003-40-B
EVALUATION OF SELECTED COMMERCIAL PREPARATIONS OF ST. JOHN’S WORT Amit K.
Shah1 , Bonnie A. Avery1,2 , Christy M. Wyandt1,2 . 1 Laboratory for Advanced Pharmaceutics, Department
of Pharmaceutics and 2 The National Center for Natural Products Research, School of Pharmacy,
University, MS 38677.
The purpose of this study was to evaluate commercial preparations of the dietary supplement, St. John’s
Wort, with respect to labeled content of active ingredients and stability. A rapid isocratic reversed phase
HPLC method was developed for the purpose of quantitation and for the analysis of formulations, based
on selected marker compounds, hypericin and pseudohypericin. Six commercial formulations (3 tablets
and 3 capsules) of standardized St. John’s Wort extract were analyzed for content. Out of these, four
preparations (2 tablets and 2 capsules) were subjected to three different stability conditions: 25 deg C,
60% RH; 40 deg C, 75% RH and 50 deg C. Evaluation was done at zero time and periodically thereafter
to assess the content, friability and hardness of the tablets, and to determine the content of the capsules.
Results revealed that initially, all the commercial preparations contained less than 50% of the labeled
claim of hypericin and varying amounts of pseudohypericin. Storage at accelerated and long-term stability
conditions showed significant changes in the content of the formulations with time. These conditions also
affected the hardness and friability of tablets.
2003-41-I
EVALUATIONS AND COMPARISONS OF STUDENT AND PRECEPTOR PERCEPTIONS OF THE
EARLY PRACTICE EXPERIENCE PROGRAM FOR PHARMACY STUDENTS
Haley P. Phelps and John P. Juergens, School of Pharmacy, Pharmacy Administration Department,
University, MS 38677
An important part of the professional education of pharmacy students in obtaining hands-on practical
experience in the actual pharmacy work environment. The University of Mississippi School of Pharmacy
has instituted an Early Experience Program that requires all students to complete structured externships
under the supervision and guidance of a pharmacist preceptor. The purpose of this study was to compare
and evaluate the views of preceptors and students who participated in the first year of the formal Early
Experience Program with respect to the effectiveness of the program in achieving its specific goals.
Separate survey instruments were developed for preceptors and students that addressed a range of aspects
and expectations of the Early Experience Program. A total of 70 surveys were completed, representing
78% of students who completed externships during the summer of 2002. Overall, the Early Experience
Program appeared to be effective in achieving the intended goals, that is, giving students a general
exposure to the practical aspects of pharmacy practice. Pharmacy preceptors indicated a high level of
satisfaction with the manner in which students performed their extern duties, and students indicated a
similar degree of satisfaction with the experience. One primary recommendation for improvement in the
program is to provide preceptors with a specific list of expectations at the beginning of the experience.
2003-42-G
BIOISOSTERIC PHENTOLAMINE ANALOGS AS SELECTIVE HUMAN ALPHA2- VERSUS
ALPHA1-ADRENERGIC RECEPTOR LIGANDS
S. A. Bavadekar1 , S. G. Lalchandani1 , S. S. Hong2 , S. Lee3 , D. D. Miller4 , S. B. Liggett5 and D. R. Feller1 .
1
Department of Pharmacology and NCNPR, University of Mississippi, MS, 2 Department of
Manufacturing Pharmacy, Chungbuk National University, Chungbuk, Korea, 3 Department of Food
Science, Keimyung College, Taegu, Korea, 4 Department of Pharmaceutical Sciences, University of
Tennessee-Memphis, TN and 5 Department of Medicine and Pharmacology, University of Cincinnati,
Cincinnati, OH.
The adrenergic receptors (ARs) belong to the family of G prote in coupled receptors. Our study is focused
on the designing of selective alpha2- vs. alpha1-AR ligands. We have evaluated the binding affinities of
phentolamine and a series of its bioisosteric analogs on alpha1- (alpha1A-, alpha1B-, alpha1D-) and
alpha2-AR (alpha2A-, alpha2B-, alpha2C-) subtypes that have been stably expressed in human embryonic
kidney and Chinese hamster ovary cell lines, respectively. Methylation of the phenolic hydroxyl group
and replacement of the 4-methyl group with varying lipophilic substituents (ethyl, isopropyl, n-butyl, and
t-butyl) yielded isosteric analogs selective for the alpha2- vs. alpha1-ARs. Within the alpha2-ARs, these
analogs bound with higher affinity at the alpha2A- and alpha2C- subtypes as compared to the alpha2BAR. In particular, the t-butyl analog was found to be the most selective, its binding at the alpha2A- and
alpha2C- subtypes being 69- to 105- fold higher than that at the alpha1-ARs and around 15- fold higher
than that at the alpha2B-AR. Further confirmation of this structure activity relationship will require
correlation of binding affinities versus functional potency among these analogs. Thus, these analogs
provide a lead to the rational design of selective alpha2-AR ligands. [Supported by USPHS GM 29358
and USDA ARS Agreement No. 58-6408-2-0009]
2003-43-G
TWO APPROACHES TO ELICTING VOCABULARY FROM AAC USERS: A SINGLE SUBJECT
DESIGN
Dana Yarbrough, Carolyn Higdon, Department of Communicative Disorders, University, MS 38677,
USA.
This presentation is master’s thesis research addressing two approaches to eliciting vocabulary from users
of AAC. The subjects were users of AAC who accessed their AAC devices through auditory scanning.
Open ended conversation and direct questions were two approaches used to elicit vocabulary during four
language sessions: baking cookies, planting a flower, having a puppet show, and making a bug box. Each
subject participated in four language sessions. Language was elicited from Subject One through openended conversation and from Subject Two through direct questions. Language samples were completed
from the language generated by each subject. Language samples assessed the semantic, syntactic, and
pragmatic components of language. Visual inspection of the results revealed that open-ended
conversation elicited more semantically and syntactically appropriate messages while direct questions
elicited more pragmatically appropriate messages. A Mann-Whitney U Rank Sum Test was the statistical
analysis used to analyze differences in semantic, syntactic, and pragmatic language in the use of openended conversation versus use of direct questions. Analysis of data revealed no significant differences
between semantic, syntactic, and pragmatic language elicited through open-ended conversation and
semantic, syntactic, and pragmatic language elicited through direct questions.
2003-44-A
CYP1B mRNA EXPRESSION and ESTROGEN METABOLISM IN CHANNEL CATFISH
COLLECTED FROM MISSISSIPPI DELTA
M. Patel1 , H. Butala 2 , C. Metzger1 , J. Rimoldi3 , and K. L. Willett1 1 Environmental Toxicology Research
Program & Department of Pharmacology, 2 Department of Chemical Engineering, 3 Environmental
Toxicology Research Program & Department of Medicinal Chemistry, University of Mississippi,
University, MS 38677
CYP1B1 is a P450 gene that in mammals is involved in the metabolism of polycyclic aromatic
hydrocarbons (PAHs) and estradiol to potentially toxic intermediates. Certain environmental
contaminants found in Mississippi sediments act by binding to the aryl hydrocarbon receptor (AhR) and
inducing a gene battery that includes CYP1B and CYP1A. In mammals, CYP1B1 metabolizes estrogen to
4-hydroxyestradiol whereas CYP1A metabolizes it to 2-hydroxyestradiol. Quantitating induction of
CYP1B mRNA or estrogen metabolism in catfish could potentially be a useful biomarker of exposure to
AhR ligands. The objective of our study is to characterize in vivo and in vitro CYP1B mRNA expression
and estrogen metabolism in laboratory raised and wild-caught channel catfish (Ictalurus punctatus, CC)
from Lake Roebuck, Bee Lake and Sunflower River. Laboratory fish were exposed to corn oil or 20
mg/kg benzo(a)pyrene (BaP) for 4 days. Using quantitative real time RT-PCR, BaP exposure induced
CYP1B mRNA in blood, liver and gonad. CYP1B mRNA in wild catfish was not statistically increased
relative to control fish. The relative tissue levels of CYP1B mRNA from Lake Roebuck fish were gill >>
blood > liver = gonad. CYP1B mRNA showed more induction in primary cultured gill cells compared to
hepatocytes following BaP exposure (5x10-9 to 5x10-5 M). Ongoing work is investigating if other AhR
ligands also induce CYP1B mRNA in vitro. Liver microsomal ethoxyresorufin-O-deethylase (EROD)
activities from wild fish were intermediate between control and BaP-exposed animals. Liver microsomes
metabolized estradiol to predominately 2-hydroxyestradiol (compared to 4 hydroxyestradiol) and
metabolism was induced by BaP. In gill microsomes, EROD activities and estrogen metabolism were
much lower compared to liver. Also gill microsomes did not form any 4-hydroxyestradiol. These results
will ultimately help characterize the utility of CYP1B as a marker of environmental contamination.
2003-45-C
CHARACTERIZATION OF THE BINDING EPITOPE OF THE ANTICANCER AGENT,
ETOPOSIDE, WITH ITS CELLULAR TARGET, TOPOISOMERASE II THROUGH SATURATION
TRANSFER DIFFERENCE NMR.
Murrell Godfrey and David E. Graves. Department of Chemistry and Biochemistry University of
Mississippi, University, MS 38677, USA.
Topoisomerase II has been demonstrated to be an effective target for anticancer agents for more than two
decades. One of the most potent topoisomerase targeting anticancer agents is etoposide (NSC 141540)
(shown below). Early studies have shown this compound to induce topoisomerase II mediated double
strand breaks in DNA; however, extensive biophysical studies indicate this compound does not bind
DNA. Hence, it is postulated that the accumulation of topoisomerase II mediated double -strand DNA
breaks arise from the interaction of the drug with the protein or the protein-DNA complex. In an attempt
to discern the binding properties of this compound (and selected analogs with topoisomerase II),
Saturation Transfer Difference-(STD) NMR experiments were performed. Using this method, the ligandbinding epitope is identified by the signals arising from the protons in closest proximity to the
topoisomerase II binding site. The results of these studies indicate strong interactions of the A, B, and
pendent rings of etoposide with the protein whilst little or no interactions were observed for the C and D
rings nor the sugar or N-alkyl sidechains of etoposide or etoposide analogs. This work is supported by
NSF grant (MCB-0099217).
2003-46-G
INACTIVATION OF THE CYTOTOXIC ACTIVITY OF REP IN, A SESQUITERPENE LACTONE
ISOLATED FROM CENTAUREA REPENS (RUSSIAN KNAPWEED) BY GLUTATHIONE
CONJUGATION.
Francis F. Tukov, Rama Sarma, V S. Gadepalli, John M. Rimoldi, John C. Matthews, Departments of
Pharmacology and Medicinal Chemistry and National Center for Natural Products Research, Research
Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi.
Ingestion of large amounts of Centaurea repens causes a neurodegenerative disorder in horses termed
equine nigropallidal encephalomalacia (ENE). ENE has no known treatment and claims the lives of a
sizable number of horses each year in the United States. Repin, the major sesquiterpene lactone isolated
from Centaurea repens is thought to be the putative neurotoxin responsible for the development of ENE.
The molecular mechanism of repin-induced neurotoxicity remains to be fully elucidated, although limited
pharmacological studies suggest that glutathione (GSH) depletion in conjunction with the inhibition of
striatal dopamine release may represent early pathogenic events in ENE development. In order to
characterize the molecular basis of repin-induced neurotoxicity, the present study was designed to identify
functional groups present on repin that can readily conjugate GSH, synthesize possible repin-glutathione
conjugate(s), and characterize and test for the presence of biologic activity in the ultimate repinglutathione conjugate(s). Results from this study indicate that the C13-a-methylene lactone moiety
present in repin seem to be the predominant conjugation site for GSH. Also, the conjugation of repin to
GSH resulted in the inactivation of repin-induced cytotoxicity in PC-12 cells. These results suggest that
the cytotoxic potential of repin in cell culture may reside on its C13-a-methylene lactone moiety. The
results also support the suggestion that intracellular GSH depletion by repin may represent an early
pathogenic event in ENE, leading to oxidative stress and ultimate disruption of nigrostriatal pathways in
the brains of Centaurea repens intoxicated horses. (This work was supported by a grant from USDA: NRI
Competitive Grants Program, USDA 2001-35208-09969).
2003-47-G
EVENT STRUCTURED LANGUAGE INTERVENTION IN A CHILD WITH BIPOLAR DISORDER
Brooke Poquette Graduate Student, Lennette Ivy, M.S., CCC-SLP, Acting Assistant Professor, University
of Mississippi, University MS 38677
This research is a case study involving a twelve-year-old male, diagnosed with bipolar disorder, and
speech and language disorders. Event structured la nguage intervention through role -play will be
incorporated into therapy and monitored to determine if a decrease in frequency of inappropriate
behaviors occur in the therapy room and at school.
2003-48-G
DEVELOPING A TREATMENT PLAN FROM A DIAGNOSTIC BATTERY
Keri Wester, Graduate Student; Stephanie Beebe M.S., CCC-SLP, Graduate Instructor, University of
Mississippi, University, MS 38677
The development of a thorough treatment plan from a diagnostic battery is an important process for
students and professionals in the field of speech-language pathology. This case study follows the
development of appropriate, effective, and functional long and short-term treatment goals from a
comprehensive diagnostic battery.
2003-49-H
CONSTRAINT PROGRAMMING APPROACH TO SOLVE RESOURCE CONSTRAINED PROJECT
SCHEDULING PROBLEM.
Haitao Li1 , N. Keith Womer1 . 1Department of MIS/POM, School of Business Administration, University
of Mississippi, University MS 38677, Hearin Center for Enterprise Science.
Constraint Programming (CP) originated in the Artificial Intelligence (AI) community. It deals with
constraint satisfaction problems (CSP) over finite domains through well-developed techniques such as
consistency maintenance and constraint propagation. Resource Constrained Proje ct Scheduling Problem
(RCPSP) belongs to the category of NP-hard problems. We will show that theoretically RCPSP has some
features which cater to the strength of CP. We implement the CP approach using Optimization
Programming Language (OPL) which depends on ILOG Solver as CP solver. A comparison with
traditional Branch and Bound method using Excel Solver proves that our CP approach is very effective.
Further we argue that because of their complementary strengths, it might be profitable to develop a hybrid
model which integrates the CP with traditional optimization to solve the RCPSP.
2003-50-H
THREE-DIMENTIONAL EFFECTS CREATED BY MACROMEDIA FLASH MX
Jun Liu, Department of Computer and Information Science, The University of Mississippi, University,
MS 38677
Though originally developed as a two-dimensional environment, Macromedia Flash MX is now widely
used in web page design to achieve three-dimensional effects with the applications of colors, layers,
transform and mask. The main reason Macromedia Flash MX is popular in web page design is that the
resultant file size is comparatively small. In this article, how to achieve 3-D effects by Macromedia Flash
MX with the applications of color, layer, transform and mask was discussed. Some models were
demonstrated.
2003-51-H
NUMBER THEORETICAL FOUNDATIONS OF CRYPTOGRAPHY
Adrian A. Wilson and Dr. Przemo Kranz Department of Mathematics University of Mississippi,
University,MS 38677
We will review the fundamental basic properties of integers, which are applied to Cryptography. It turns
out that very simple properties of integers (modular arithmetic) can be applied in the process of
encryption and decryption. In particular, we will review the most current Cryptosystem-RSA. It is a wellknown fact that multiplication of two integers is easily done but a factoring of a (composite) large integer
is next to impossible. We will show appropriate examples. Therefore encoding which is based on
multiplication is easy and decoding which is based on factoring is practic ally impossible, unless one
knows the key, in which case decoding is essentially a multiplication.
2003-52-H
PROVIDING STREAMING CAPABILITIES TO ONLINE APPLICATIONS
Krishna Sajja and Dr. Pamela Lawhead, Department of Computer and Information Science, University of
Mississippi, University MS 38677, USA.
Service providers and large corporations are being challenged to meet the ever-increasing needs of
delivering significant volumes of streaming media content. Streaming allows large files to be processed as
they are downloaded remotely, thereby avoiding the delay associated in downloading the entire file. This
research focuses on the unique requirements of streaming, design of a streaming protocol to enable webbased processing of large data files, and how these needs relate to building an optimal streaming delivery
protocol.
2003-53-H
HOSTING A VIRTUAL PORTAL IN AN ONLINE ENVIRONMENT
Luis Paris. Department of Computer and Information Science, University of Mississippi, University, MS
38677, USA.
The use of virtual reality in online education creates a plethora of opportunities for institutions to improve
and complement the student learning experience. Virtual reality technology makes possible the delivery
of high quality 3-D animations and graphics that enhance particular concepts that would otherwise be
harder to explain and understand. It also provides a 3-D virtual environment where students can immerse
themselves and interact directly with their peers and the virtual world itself. Therefore, virtual reality
provides a didactical environment for instructors and students to teach and learn. They also benefit by
getting a hands-on practical exposure and knowing how to better exploit the tools at their disposal.
However, current distance learning and online education systems have not fully exploited the advantages
of virtual reality. Moreover, there does not seem to be a coherent integration between virtual reality
content and online course material. The main goal o! f this project is to provide the software framework to
allow the delivery of interactive animations and virtual reality content, and seamlessly integrate this 3-D
technology with distance learning material displayed on the Internet. This integration translates into a 3-D
portal and a web browser encapsulated in a Graphical User Interface (GUI) window. Web links launch
animations on the 3-D portal, and events on the latter load related web content on the browser.
2003-54-I
TECHNICAL AND POLICY ISSUES FOR RESERVE OF ONLINE COURSEWARE
Keyur Patel and Dr. Pamela Lawhead, University of Mississippi
Copyright owners have exclusive rights to some of the uses of protected work against reproduction,
distribution, the making of derivative works, and publication. In order to provide the necessary balance
between the rights of the copyright owner and the dissemination of information for educational purposes,
Section 107 of the US Copyright Act of 1976 sets forth Fair Use and factors to be evaluated in
determining whether a particular use of copyrighted information, without prior permission, is a fair and
permitted use. As there is no simple test to determine what is Fair Use for educational multimedia, only
courts can authoritatively determine whether a particular use is a “Fair Use.” The purpose of this research
is to provide guidance to developers in fixing the criteria for reserves of licensed online courseware in
order to make the online use of copyrighted educational information lawful under Fair Use.
2003-55-H
INFORMATION STORAGE AND MANAGEMENT IN LARGE WEB-BASED APPLICATIONS
USING XML
Manirupa Das, and Pamela B. Lawhead. Department of Computer and Information Science, University of
Mississippi, University MS 38677, USA. [email protected], [email protected]
The Extensible Markup Language [XML], was intended to be a meta -language, when it was initially
approved as a Web Standard by the World Wide Web Consortium (W3C), in February of 1998. Since
then, it has come a very long way in applicability and popularity and is fast becoming the Standard for
Data Interchange over the Web. XML has now formed the foundation for a completely new way of
communicating across the Internet. The power of XML to be applied universally to a number of areas lies
in the fact that it is a clean standard and provides a very simple way for a document to carry information
about itself. In a generic sense, this would imply that XML infuses the information itself with
"Intelligence." This feature of XML can be harnessed to lend the flexibility and the information storage
and management capability desirable in most Web-based applications. This paper researches and
evaluates the tradeoffs, advantages and issues involved in applying XML to the storage and management
of data and/or documents in the implementation of a large Web - based application, such as an Online
Delivery System for Courseware.
2003-56-H
SSM – PROXY FOR THE REAL-WORLD EXPERT IN ONLINE COURSE DELIVERY
Ravikumar Darbhamulla, Manirupa Das, Dr.Pamela Lawhead, Institute for GeoSpatial Course
Development and Delivery, Kinard Hall, Room No: 368,University, MS - 38677
Distance education has entered a new era, where it is now possible for courseware to be delivered online,
in a very efficient yet appealing manner. To that end, it becomes imperative to address a number of
pedagogical issues that crop up in the design of a dynamic web-based system for the delivery of
courseware. Traditional education generally involves two main entities: an Expert (teacher), and some
form of reference material such as a textbook. The Expert imparts knowledge interactively in the real
world, and is in some sense the more 'active' or 'intelligent' agent, whereas the textbook is just reference
since it has limited scope, and hence is the 'passive' or 'static' agent. Thus, the pedagogical issue that
needs the most immediate attention, while dealing with learner-centered online course creation, is the
issue of how to emulate the real-world Expert in a virtual learning environment. The best way to do this is
to get constant feedback on the performance and learning style of the student, via student status
monitoring. This is the concept that forms the basis of our research. Hence, we developed the Student
Status Monitoring Tool (SSM), which takes the proxy role of the teacher in Online Environment.
2003-57-F
VIRTUAL LABORATORIES USING INTERACTIVE 3-D SIMULATIONS FOR REMOTE SENSING
EDUCATION
Parishweta Bhatt, Michelle Aten, Dr.Pamela B.Lawhead. Institute for Geospatial Course Development
and Delivery. The University of Mississippi
The proliferation of virtual reality technology in the 21st century offers educators a unique opportunity to
introduce students to activities, exercises, and environments that they might never access in the real
world. Work is underway at the The Institute for Geospatial Course Development and Delivery to develop
a 3-D, web-hosted, interactive virtual laboratory environment that could be used to simulate field
exercises, offer equipment training, or host embedded, interactive animations. These laboratories provide
students with simultaneous access to collaboration tools, enrichment material, data analysis software,
student monitoring statistics, and multiple views of the virtual landscape. The prototype version of the
project simulates the collection of ground control points using a GPS receiver in a distinctive virtual
environment.
2003-58-H
ASSIGNMENT BETWEEN SAILORS AND BILLETS FOR AS COMMUNITY
Yuting Cheng, Hearin Center for Enterprise Science, University of Mississippi, University, MS 38677,
USA
This project is to solve an assignment problem for m sailors and n billets. Each sailor could be assigned to
at most one billet and for each billet, there is at most one sailor. Hypothetical sailors and billets are
generated by simAs, an excel based process to generate a representive list of sailors and billets for AS
community. Utility functions are also developed for sailors across billets and billets across sailors. We
implemented Munkres' assignment algorithm to maximize the total utility for billets and at the same time,
give each sailor several choices. Different approaches are used to do the assignment. We compare the
results from different approaches and do statistical analysis on them. The details of the problem, the
assignment approaches and the results will be presented.
2003-59-I
LEARNING STYLE AND INSTRUCTION IN THE ESL/EFL CLASSROOM.
Yanling, Hwang. Department of Curriculum and Instruction University of Mississippi, University MS
38677, USA.
Teaching English as a second language (ESL) or English as foreign language (EFL) has changed
extremely over the past two decades (Kang, 1999). Considering the curricula, teaching methods, and
teaching materials, educators have developed them to meet the changing needs of the ESL/EFL
population. In other words, attention should be drawn to effective language teaching and learning, and
curricula design related to learners needs. However, the curricula of many ESL/EFL programs are still
linear or systematic and do not allow much room for individualization of instruction. This paper begins by
providing a brief historical perspective on learning style, which has been considered as preferred or
habitual patterns to responding to the environment. It focuses on the role of learning style and individual
difference in ESL/EFL learning. An awareness of individual differences in learning has made ESL/EFL
educators and program designers more sensitive to their role in teaching and learning. Therefore, the way
to help ESL/ EFL educators and program designers gain a better understanding of the human differences
in learning is discussed. Moreover, this paper attempts to suggest the way to facilitate educators in
selecting classroom-teaching instruction when they design courses, especially in the writing course.
2003-60-I
THE EFFECTS OF CAPTIONS TO AUTHENTIC ENGLISH VIDEOS IN FOREIGN LANGUAGE
INSTRUCTION IN TAIWAN.
Yanling, Hwang. Department of Curriculum and Instruction University of Mississippi, University MS
38677, USA.
Over the years, greater emphasis is now placed on teaching English as a tool for communication and
TV/video plays an important role in the transmission of information and is a powerful medium in
language teaching. Presenting captions is another function of television/video which aides the visual
channel to communicate verbal information. However, whether the captioned TV and videos improve or
impede students learning will be concerned in this study. This study will investigate the effect of the use
of ESL instructional video captioning on EFL college students language comprehension in Taiwan. The
participants of this study will be freshman students enrolled the national institute of technology in central
Taiwan. The experiment will proceed for five weeks to watch two 15-minute episodes from the ESL
instructional videotape, Connect with English, in the listening class once a week. The control group
watches the episode videos without any captions whereas the experimental group watches the videos with
captioning. General English Proficiency Test (GEPT) and Content-specific test (CST) will be
administered to assess students language performance. The Descriptive statistics, ANCOVA will be
utilized in data analysis.
2003-61-I
AN ANALYSIS OF LEARNING STYLES AMONG EFL STUDENTS AND THE EFFECT ON THEIR
LANGUAGE PERFORMANCE.
Yanling, Hwang. Department of Curriculum and Instruction University of Mississippi, University MS
38677, USA.
The grammar-translation method has been prevalent in EFL teaching of Taiwanese secondary schools
recently. Owing to the university entrance exam tests students' reading and writing skills, teachers tend to
focus on bits and pieces of language structures, including grammar, vocabulary, and production practice.
Learners master the language by mechanically reciting and memorizing the grammar. Teachers routinely
give the same lectures and tests and assign the same papers and projects to their students without regard
for their students' individual learning abilities and preferences. Much research has been shown that
students who prefer to engage in other activities may be given a low rating by a professor who teaches by
lecture. Eventually, students lose interest in class and refuse to learn any more. The purpose of this
causal-comparative study is to investigate the effect of language learning styles of English-major senior
college students in Taichung, Taiwan, on students' scores on the TOEFL. The independent variable in this
study is learning styles, and the dependent variable is students' score on the TOEFL. Learning styles are
defined as the preferred or habitual patterns of mental function and dealing with new information.
2003-62-I
VALIDATION OF THE CHICK SEPARATION STRESS PROCEDURE.
Jason E. Warnick1 , Mathew W. Feltenstein 1 and Kenneth J. Sufka 1,2,3 1 Department of Psychology,
2
Department of Pharmacology, and 3 The Research Institute of Pharmaceutical Sciences, University of
Mississippi, University, MS 38677.
Previous research has established the chick separation stress procedure as a high-throughput in-vivo
anxiolytic screen. The present research sought to 1) enhance model utility and reduce potential confounds
through several procedural changes and 2) to extend the generalizability of the model through testing a
larger number of positive and negative drug probes. At 7-days post-hatch, chicks received IM injections
of either vehicle or a single drug probe 15-min before being placed into an isolation chamber either with
or without mirrors for a 3-min observation period. Of the positive drug probes, chlordiazepoxide,
clonidine, imipramine, meprobamate, and pentobarbital produced a significant anxiolytic effect;
buspirone did not. All of the negative drug probes, which included amphetamine, caffeine,
chlorpromazine, haloperidol, and scopolamine, did not produce an anxiolytic effect. These findings
extend the generalizability of the chick separation stress procedure as a high-throughput anxiolytic drug
screen.