Northeast Regional
Undergraduate and Graduate Student
Sigma Xi
Poster Conference
Cornell University, Ithaca, NY
April 21st, 2007
Schedule
9:30 to 10:30 AM
10:30 AM to 12:30 PM
12:30 to 1:30 PM
1:30 to 2:30 PM
2:30 PM
2:30 PM
Arrival, set up, and breakfast snacks, G10 Biotech
Poster session, judging, and networking
Lecture by Dr. David Winkler, Cornell University, "Migration and
dispersal: key life history traits in swallows"
Lunch, networking, and poster awards
Sigma Xi members and officers meeting
Cornell University tour for students
Participating Schools
Albany Medical College
Boyce Thompson Institute of Plant Research
Bryant University
Colby College
Cornell University
Dominican College
Fordham University
Hobart and William Smith Colleges
Hunter College
Ithaca College
Lehman College
Le Moyne College
McGill University
Rensselaer Polytechnic Institute
Rhode Island College
Rochester Institute of Technology
Russell Sage College
SUNY Binghamton
SUNY Buffalo State
SUNY Oswego State
SUNY Plattsburgh State
SUNY Stony Brook
University of Connecticut
Wells College
Western Connecticut State University
Yale University
Organizers
Kestas Bendinskas, SUNY Oswego
James Mandel, Cornell University
Graduate Poster Judges
Cristina Clement, Lehman College
Howard Howland, Cornell University, Chief Judge
Undergraduate Poster Judges
Karen Almeida, Rhode Island College
Leigh Bacher, SUNY Oswego
Ipsita Banerjee, Fordham University
Danielle Garneau, Colby College
James MacKenzie, SUNY Oswego, Chief Judge
Dina Newman, Rochester Institute of Technology
Abstract formatting and editing
Kestas Bendinskas, SUNY Oswego
Chris Finnigan,, SUNY Oswego
James MacKenzie, SUNY Oswego
Sponsored By
Sigma Xi
Cornell Chapter of Sigma Xi
ABSTRACTS:
1) U
The Effect of Constant Light on Motility Rhythms in Chick Embryos
Ashley Tinklepaugh and Christina Wahl
Department of Biological and Chemical Sciences, Wells College, Aurora, NY
Constant light (CL) disrupts melatonin rhythms in chicks. To determine when rhythmic patterns of activity and rest develop
in chick embryos, and whether this is affected by CL, Cornell K-strain eggs were incubated with either no light source, or
in windowed incubators over which bright, constantly lit lamps were positioned. Eggs were windowed at 2-3 days of
incubation. Electrodes attached across the egg's smallest diameter recorded field potentials using a 500 mV DC
preamplifier and a WinDaq waveform recorder. Recordings were made over twenty-four hour periods. Waveforms were
converted to absolute voltages, then each voltage was assigned a "0" value if it occurred at or below background noise
levels, and a value of "1" if above. Scores were summed over 10-minute intervals, and plotted. Graphs were analyzed for
periodicity and amplitude. Results show that CL embryos are not showing any clear periods of rest and activity and that any
amount of light significantly dampens rhythmicity (cyclic activity) significantly (t = 0.10). When embryos are allowed to
develop in the dark, or with exposure to dark intervals, they show definite periods of activity and rest that do not appear in
CL with an average period being 12 hours. Light also affects survival rate with embryos raised in CL living only 7% of the
time compared to embryos raised in darkness living 33% of the time.
2) U
Isolation and Identification of Bacteria from Mercury-Contaminated Soils
Laura Telman and Ruth A. Gyure
Western Connecticut State University, Danbury CT
Heavily contaminated soils, especially those enriched with heavy metals or hydrocarbons, are of great interest in the search
for novel microbes. Theoretically, the unusual metabolic characteristics of species selected for in these environments may
be useful in efforts to remediate similarly contaminated sites, and study of these organisms could lead to better
understanding of bacterial metabolic capabilities and the application of this knowledge in remediation efforts. The study
site for this project is an abandoned hat factory in Danbury Connecticut called Barnum Court. Classic microbiological
culture techniques for enrichment and bacterial isolation were used, and both metabolic (Biolog) and molecular techniques
for identification were employed to characterize the “most numerous culturable heterotroph” (MNCH) from each of several
zones of mercury soil concentration in bulk soil test plots and in rhizoshpere soil attached to genetically modified trees that
were part of a phytoremediation study. The MNCH technique is a dilution method first described by Ralph Tanner, who
has discovered several new species of bacteria in soils contaminated with hydrocarbons using this approach. In this study,
at least one isolate proved to be highly interesting in that it produced an extremely unusual growth pattern on media
selective for Pseudomonads. Further analysis of the organism’s metabolic characteristics and the chemical structure of the
organic crystals formed in the agar helped identify it as Pseudomonas chlororaphis, a fluorescent pseudomonad known to
have capabilities that might allow its survival in contaminated environments. Another isolate produced a foamy detergentlike substance which turned out to be rhamnolipid, characteristic of certain types of Pseudomonads and of great interest in
biotechnology research. Final identification of all the MNCHs will hopefully lead to additional interesting results.
3) G
Shading by an invasive macrophyte accounts for its cascading ecosystem effects
Rebecca A. Urban, John E. Titus, and Wei-Xing Zhu
Biology Department, Binghamton University, Binghamton, NY
The submersed macrophyte Utricularia inflata (inflated bladderwort) is a recent invader of Adirondack Mountain lakes
(NY, USA). Previous experiments suggest that U. inflata may change nutrient cycling in Adirondack lake ecosystems by
reducing the growth of native isoetid macrophytes, and altering key features of sediment chemistry. A 13-week greenhouse
experiment was conducted to test the hypothesis that shading is the primary mechanism behind this rootless macrophyte’s
detrimental impact on the native short-statured species, Eriocaulon aquaticum (pipewort). Eriocaulon aquaticum has an
extensive root system that takes up carbon dioxide from sediment, and releases oxygen—thereby creating an oxidized
sediment environment. As we increased shading by adding layers of shade cloth (1-4 layers), growth and asexual
reproduction by the native species significantly declined (p<0.001), and the change of sediment chemistry intensified.
Shading decreased E. aquaticum’s oxidizing effect on the sediment (p<0.0001) and increased the concentrations of
porewater carbon dioxide (p<0.0001) and extractable ammonium (p<0.0014). There was on average an 83% light
attenuation under the cover of U. inflata; this value was close to the light attenuation from two-layers of shade cloth (82 %).
The impact of U. inflata on the native species closely matched the impact of shade cloth with similar light attenuation. Our
results suggest that the primary mechanism behind U. inflata’s impact on native isoetids and sediment chemistry is shading.
4) U
Identification of Air-Phase Fatty Acids: Both Retronasal and Orthonasal Failure
Richard M. Tamburrino and Bruce P. Halpern
Dept. Molecular and Cell Biology, Cornell University, Ithaca, NY
Retronasal and orthonasal identifications of three fatty acid odorants were presented air-phase at 22-25oC three times each
during both orthonasal and retronasal situations. A random order of odorant delivery was obtained by using a page of
random digits and blindly starting from a point in the middle of the page. The odorants used were 40% linoleic and oleic
diluted in mineral oil and 100% solid form stearic acid powder. 16 subjects were tested (10 females, median age = 21.5) on
a digital computer from a display of six identifiers, after practice and familiarization trials. There were no indications given
of “correct” identifications. When presented in the orthonasal situation inhalation intervals were self initiated by pressing
the spacebar and ended upon selection of a descriptor. For the retronasal situation exhalation intervals began upon detection
by a microphone and also concluded upon selection of a descriptor. Subject’s identifier/ odorant pairing were recorded and
timed. There were no significant differences across the identifiers and subjects, p > 0.90 (Chi-Square and Friedman
ANOVA By Ranks for Repeated Measures tests). However, the identification “flour” was selected for linoleic acid on 15 of
48 orthonasal and retronasal trials; “silly putty”, for retronasal oleic and stearic acids on 12 of 48 trials. Chance
identifications would be 7 of 48. This suggests that subjects might learn ‘correct’ identifications for these fatty acids.
CONCLUSIONS: Air-phase fatty acids are not selectively identified from a closed list by untrained subjects. Trained
subjects may make selective identifications.
5) U
Phase Transition-Like Properties of Certain Discrete Dynamic Systems
Steve Uurtamo and Valentin E. Brimkov
Buffalo State College, Buffalo, NY
Discrete dynamic systems are widely used in mathematical modeling of various situations and phenomena observed in a
broad range of sciences, such as physics, chemistry, biology, finances and economics, sociology, psychology, and
medicine. Therefore properties of dynamic systems are attracting an increasing interest in the scientific community. As a
rule, dynamic systems exhibit chaotic behavior. Moreover, sometimes a very small perturbation of a parameter (or
parameters) defining a particular dynamic system leads to dramatic change of the state of the system and its properties.
Phenomena of this kind, sometimes labeled by the term “phase transition” have been studied in different contexts. Usually
these can be well observed by means of graphical visualization of system’s behavior. Our research aims to characterize the
critical points of a class of discrete dynamic systems known as “quasi-affine transformations”. The images generated by
iterating such a transformation are a class of fractals. Our experimental approach makes use of a specialized computer
system developed for the purposes of our experiments. Through it one can generate series of images corresponding to a
particular transformation and its perturbed versions, discover interesting patterns, and observe critical points at which the
images change their character. On this basis, theoretical explanation of the obtained empirical results is sought.
6) U
The Influence of Low Frequency Vibration on Tactile Discrimination
Stephanie Nye, Christina Wahl, and Deborah Gagnon
Wells College, Aurora NY
The ability to sense differences among small objects involves both touch-receptor response thresholds (discrimination) and
perception. Workplace exposure to low frequency vibrations increases response threshold, and produces diffuse
neuropathies. A classic challenge to tactile discrimination involves blind sorting of safety pins from dry rice. Conditioning
to low frequency vibrations was expected to increase the time required for this task. 60 participants signed informed
consent forms written to APA guidelines. The time required to locate one safety pin was recorded for randomly presented
containers, one filled with a mixture of rice and pasta (R&P), the other with rice and salt (R&S). The participant's hand was
then placed, for one minute, on a plate vibrating at 31Hz , followed by an immediate search for safety pins in R&S again
(Trial 1; 20 participants) or R&P (Trial 2, 20 participants; Trial 3, 20 participants). In Trials 2 and 3, a second postadaptation search was conducted after 5 minutes. Mean times for Trial 1 were: R&P, 38.5 seconds (standard error or S.E.
12.4 seconds); R&S, 21.1 seconds, S.E. 5.7seconds; Adapted, 8.6 seconds, S.E. 1.6 seconds. Mean times for Trial 2 were:
R&P, 49.5 seconds (S.E. 14.4 seconds); R&S, 26.5 seconds, S.E. 7.9 seconds; Adapted, 38.54 seconds, S.E. 9.0 seconds;
post-adaptation, 12.0, S.E. 11.2. Mean times for Trial 3 were R&P, 34.0, S.E. 10.6; adapted, 23.8, S.E. 4.2; and postadaptation, 25.2; S.E. 5.5. These results suggest that adaptation to low frequency vibrations eliminates the effect of learning
on search times in rice and pasta.
7) U
Role of XPF in NER: DNA Nucleotide Excision Repair
Tania Wyss, Barbara Orelli, and Orlando Schaerer
Department of Pharmacological Sciences, SUNY Stony Brook, Stony Brook, NY
UV radiation causes DNA lesions in the cells; a problem more relevant today with the public’s prolonged sunlight exposure
and depletion of the ozone layer. NER, Nucleotide Excision Repair (NER), removes bulky adducts resulting from sunlight
or environmental mutagens. A deficiency in the genes participating in the NER mechanism leads to the known human
syndrome xenoderma pigmentosum (XP), marked by a 2000-fold increased incidence of skin cancer, underlining the
importance of NER to maintain genome stability. In our research, the various XP proteins (XP A-G) forming the excision
complex and the subsequent chronological steps of the NER mechanism are studied. Specifically, the ERCC1-XPF
involved in 5’ incision is investigated, focusing on ERCC1-binding and DNA interaction of XPF. The goal of my project is
to investigate how a helicase-like domain in the XPF protein contributes to the DNA binding and NER activity. For this
purpose 4 point-mutations were introduced into the 2’717bp XPF coding sequence via designed primers and PCR in the
pFastBacI plasmid. Next, the plasmid will be used to generate bacculoviruses to infect insect cells for the expression and
purification of the mutant XPF proteins. DNA binding activity of the mutant proteins will be measured using band shift
assays and NER activity is measured in vitro by monitoring the excision of an oligonucleotide containing a damaged site
from a plasmid. The study of XPF will contribute to our understanding NER, which is fundamental for genome stability.
8) U
The Expression of Wnt and Frizzled Genes in Human Embryonic Stem Cells
Ujunwa Cynthia Okoye and Hsien-Yu Wang
Stony Brook University, Stony Brook, NY
Wnt-Frizzled signaling plays an important role in embryogenesis, cell fate determination and pattern formation in
development. Wnts are secretary ligands and Frizzleds are membrane receptors for Wnts. The binding of Wnts to Frizzled
leads to activation of its signaling pathway which induces gene expression. Inappropriate activation of Wnt signals
produces cancer. There are 19 Wnt and 10 Frizzled genes being identified in human so far. Two members of the LDL
receptor related proteins, LRP5 and LRP6, have been shown functionally as co-receptors for Frizzleds in the Wntstimulated signal pathway. Recently the success in culture of Human Embryonic Stem Cells (HESC) allows researchers to
use these cells as a model system to further understand human development and diseases, which cannot be conducted
directly on an embryo. It has been reported that activation of Wnt signaling maintains the pluripotency of HESC and the
expression of Wnt and its receptor is essential for self renewal of these stem cells. However, not much is known about
which Wnt and Frizzled genes are expressed in these stem cells. It is important to determine the expression pattern of these
genes in order to understand their roles in stem cell renewal and cell differentiation. By using reverse transcription in
tandem with polymerase chain reaction we analyze gene expression of Wnts and Frizzleds in HESC. Results show that of
the 19 members of the Wnt family, only Wnt-5a and Wnt-5b are not expressed in HESC. All Frizzled genes, except
Frizzled-8 and Frizzled-10, are expressed. Further research to compare gene expression in HESC with that in Human bone
marrow mesenchymal cells, mouse stem cells and mouse embryonic fibroblasts will provide better understanding of WntFrizzled signaling on pluriopotency, self renewal and differentiation of HES cells.
9) U
Behavioral and pharmacological evidence for two different mechanisms of habituation learning
in the olfactory bulb
P.D. Magidson, A.M. McNamara, T.A. Cleland, D.A. Wilson, and C. Linster
Department of Neurobiology and Behavior, Cornell University, Ithaca, NY
Male mice readily investigate the odors of conspecific males, which is useful for identifying strangers versus familiars and
dominants versus subordinates; however, males will habituate to the odors with repeated presentations. We examined the
effect of manipulating intertrial interval length on the habituation to a conspecific male's bedding odors. We habituated
male mice to conspecific odors using either 20 second or 5 minute intertrial intervals (ITI). First, we found a significant
difference in memory duration as a function of ITI length: mice habituated with 5 min ITIs remembered the odor for 20
minutes whereas mice habituated with 20 sec ITIs remembered the odor for only 2 minutes. Second, we found that in
agreement with recent electrophysiological data (Wilson 1998 J Neurophys 79: 1425; Best & Wilson 2004 J Neurosci 24:
352), habituation with very short ITIs was significantly impaired when class II/III metabotropic glutamate receptors were
blocked (LY341495, 2.5mg/kg IP), whereas habituation at the longer ITIs was not affected. Third, we found that blockade
of NMDA receptors with the specific antagonist MK-801 (0.2mg/kg IP) did not affect habituation at the shorter ITIs, but
significantly impaired habituation at longer ITIs. Together, these results show that two pharmacologically distinct
mechanisms underlying olfactory habituation exist in mice.
10) G
A novel alpha-Proteobacterial root nodule symbiont associated with Lupinus texensis
Cheryl P. Andam and Matthew A. Parker
SUNY Binghamton, Binghamton, NY
Although most legumes in the genus Lupinus utilize strains of Bradyrhizobium as nodule symbionts, 28 nodule isolates
from two populations of L. texensis could not be assigned to Bradyrhizobium or to any other known genus of nodule
bacteria. All isolates exhibited a novel length variant in the 23S rRNA 5' intervening sequence region that differed from
strains of Bradyrhizobium. Phylogenetic analysis of nearly full-length 16S rRNA genes indicated that the L. texensis
symbionts were related to strains in three non-symbiotic genera of -Proteobacteria (Chelatococcus, Bosea, Balneomonas).
This lineage formed a sister group to the genus Methylobacterium. The L. texensis symbionts had a nodA gene closely
related to that of Mesorhizobium plurifarium, and partial sequences for nifH and nifD genes placed the L. texensis
symbionts with strains from the genera Rhizobium, Sinorhizobium and Mesorhizobium. Thus, it is likely that the L.
texensis symbionts acquired both nif and nodA genes by lateral transfer from other rhizobial genera. The L. texensis
symbionts formed effective, nitrogen-fixing nodules on their original host legume, and were able to significantly increase
plant growth. The L. texensis symbionts did not form nodules on three other species of Lupinus, or on species of several
other legume genera. L. texensis plants failed to form nodules when inoculated with Bradyrhizobium strains associated with
other Lupinus species. These results indicate that L. texensis has a relatively specialized symbiotic interaction with a
bacterial lineage that acquired the capacity for nodule symbiosis separately from other rhizobial groups in the αProteobacteria.
11) U
Experimental Research on Veto System of Daya Bay θ13
Jiayan Dai and Jim Napolitano
Rensselaer Polytechnic Institute, Troy, NY
Daya Bay Neutrino Experiment is a project being conducted by an international team of scientists, which is designed to
measure the mixing angle, θ13, in neutrino oscillation. The goal of Daya Bay experiment is a measurement of Sin2(2θ13) to
0.01 or better. For such sensitive reactors, other particles, e.g. isotopes produced by cosmic rays, will also be detected. The
veto system is built to distinguish false signals given by non-neutrino particles and to subtract them from total information,
which is a vital process helping to approach the goal. RPI is one of the collaborators focusing on issues of muon veto
system, for example, water tank prototype, computer simulation, water conditioning, which are about background noise
reduction and <1% precision accomplishment. The research involved is to study, how different background noises and
experimental environment affect the detection, and in what (possible) way those effects can be reduced or eliminated to
reach high precision. Most recently, the focus is on muon system's water conditioning and specification. Case study and
water attenuation length measurement for different water sample conducted in Brookhaven National Lab are done. The
research results will provide a guide on water specification design specified for Daya Bay, how and how much effort, labor,
and money should be reasonably devoted to the design.
12) U
An Analysis of an After-School Program and its Impact on Children and Their Families
Elizabeth Grossfeld, Allison Hunt, Brittany McCutcheon, Matthew Hautala, Roshelle Lewis, Dawn Lo, and Judith PenaShaff
Psychology Department, Ithaca College, Ithaca, NY
After-school programs have proliferated in recent years with the hope to ameliorate children’s academics and foster socioemotional development. The focus of this study was to evaluate the impact of an academic-based after-school program on
elementary school children and their families. Focus groups, interviews, surveys, and student grade records were used to
assess the program’s effect on academic achievement, socio-emotional development, family involvement, and perceptions
of the program. Analysis of the parent questionnaire (N = 49) revealed overall satisfaction with the program and its staff,
and positive perceptions regarding the impact of this particular after-school arrangement. Researchers also compared grade
reports and standardized test scores of after-school and non-after-school students to compare academic performance.
Preliminary mean comparisons of fourth and fifth grade levels revealed that after-school students in fifth grade performed
better on state-mandated states than non-after-school students; these results did not hold true for after-school students in
fourth grade. In addition, after-school students, whose grade scores showed higher means in reading, social studies, and
science, maintained higher attendance rates. The results varied by grade level. Differences, however, are not significant.
This program evaluation will help the school to address the needs of the students and their families, as well as offer ideas
for future improvement.
13) U
Qualitative Evaluation on a Youth Employment Program
Christine George, Hannah Priestley, Caitlin Rich, Michael Berlin, Christina Corsaro, and Jacqueline Gomez
Psychology Department, Ithaca College, Ithaca, NY
The purpose of this evaluation is to assess the short term impacts of a youth employment program on participating
adolescents and the Sciencenter in Ithaca, NY, one of the organizations that host this program. We used data collected
through interviews with staff, focus groups with youth in the program, and surveys with the Sciencenter visitors to gather
participants’ perception about the program and its effectiveness. Data from visitor surveys revealed high visitor satisfaction.
Staff’s perceptions were both positive and negative about the impacts of the program. Youth in the program have mainly
positive perceptions about the program and felt very proud of their contributions. However, they felt frustrated about the
time limitations imposed by the program grants. The program will benefit from a structure that is less influenced by
changing grant requirements which might result in better youth and staff dynamics.
14) G
Comparative Analysis of Preparation Techniques for Proteomic Research
Robert Birdsall1, Kestas Bendinskas1, and James A. MacKenzie2
1
Chemistry Department and 2Department of Biological Sciences, SUNY Oswego, Oswego, NY
The goal of this research was to find a cost effective solution in the depletion of high abundant proteins for proteomic
research in biomarker discovery related to chronic conditions in organisms. A comparative analysis of the Aurum Affi-gel,
Albusorb, and IgY-12 depletion kits from Bio-Rad, Biotech, and Beckman Coulter, respectively, were performed. Each kit
was assessed on quality of ligand specificity in 1D-PAGE as well as resolution and spot reproducibility in 2D-PAGE.
Protein depletion rates of 75%, 67%, and 93% were determined for the Bio-Rad, Biotech, and Beckman Coulter kits,
respectively. Volume analysis of paired spots before and after protein depletion showed a volume increase in all three kits.
The Bio-Rad and Biotech kit were determined to be inadequate for proteomic research due to non-specific binding, lack of
resolution in 2D-PAGE analysis and irreproducible results. The Beckman Coulter kit was determined to be sufficient for
the proposed research into biomarker discovery due to ligand specificity, increased resolution in 2D-PAGE analysis, and
reproducibility.
15) U
Dye Encapsulated Germania-Silica Nanocomposites and their Photophysical Properties
Marsiyana M. Henricus and Ipsita A. Banerjee
Chemistry Department, Fordham University, Bronx, NY
Hollow nanospheres of germania-silicates were grown using vesicles as templates. The efficacy of growth of the
nanospheres was investigated using different types of lipids. Some of the lipids examined include phosphatidylcholine, 1,2diacyl-sn-glycero-3-phospho-L-serine and N-Acetyl-D-sphingosine. From our studies conducted it appears that the surface
charge as well as the chemical structure of the templates are important factors for the growth of the nanocomposite spheres.
In the case of negatively charged lipids, the use of co-surfactant such as octadecylamine was necessary in order to promote
the growth of the nanospheres. More vesicles appeared to be coated with the nanocomposites when phosphatidylcholine
was used in the presence of octadeceylamine followed by 1,2-diacyl-sn-glycero-3-phospho-L-serine. Although N-Acetyl-Dsphingosine was also efficient in promoting the growth of the nanocomposites after octadecylamine was added, the yield of
coated vesicles seemed to be lower compared to the other lipids. The results indicate that GeO 2-SiO2 nanoshells can be
synthesized based on the specific interior surface charge of the vesicle templates. Further, we encapsulated various
triphenylmethane dyes within the vesicle templated nanocomposites and the photophysical properties of those dyes were
studied. Bromothymol blue, bromocresol green and bromocresol purple were encapsulated and showed an enhancement in
fluorescence intensity due to the restriction in rotational motion of the aromatic rings in the interior of the shell. The
methodology presented could potentially be applied to the formation of multidimensional porous nanocomposites with
chemically-tailored microcavities for sensor applications.
16) U
Small Mammal Assemblages under Urban Influence in Central Maine
Katherine Renwick, Alexandra Sadanowicz, Genevieve Dubuque, Rosalind Becker, Claire Thompson, and Danielle
Garneau
Biology Department, Colby College, Waterville, Maine
During fall 2006, we sampled small mammal populations using Sherman live traps at three sites in central Maine. Our goal
was to examine the variation in small mammal assemblages in habitats with different levels of disturbance (e.g., airport
meadow, highly disturbed early-successional forest, and mowed field bordered by late-successional mixed forest). Our
results indicate that the highest diversity occurred along the edge of the late-successional forest. Peromyscus spp.
dominated the early-successional forest and late-successional forest edge sites, but meadow voles (Microtus
pennsylvanicus) were most common in the airport meadow. Because Peromyscus leucopus and P. maniculatus are difficult
to distinguish in the field, we are currently analyzing saliva samples in an effort to find a more accurate method of
identification. Salivary amylase electrophoresis has proven a useful technique for correctly differentiating between the two
Peromyscus species. Preliminary results indicate a 70% correspondence between field and laboratory identification, further
supporting the need to employ molecular as well as field techniques in ecological experiments. The results of this research
will help elucidate the effects of habitat disturbance on the distribution and abundance of small mammals, which play an
important role in forest ecosystems as seed dispersers, prey to larger carnivores, and vectors of disease. Small mammal
diversity may also serve as an indicator of overall ecosystem health, and thus provide information about the effects of
development on Maine’s natural communities.
17) U
Tailored Nanocomposites Derived from Peptide Bolaamphiphiles
Monica Z. Menzenski and Ipsita A. Banerjee
Chemistry Department, Fordham University, Bronx, NY
The growth and self-assembly of peptide bolaamphiphiles with varying chemical compositions was investigated. The selfassembly process was examined at different pH. The formation of various nanostructures was examined using atomic force
microscopy, transmission electron microscopy, dynamic light scattering, ultraviolet-visible spectroscopy, and infrared
spectroscopy. It was observed that the types of nanostructures formed were dependent on both the growth conditions and
the chain lengths of the hydrocarbons linking the head groups. As the size of the hydrophobic chain length connecting the
amino acid head groups increased, the nanotubes were formed in higher yield and were observed to be more elongated and
well-defined. In some cases, nanofibers, spheres, and rod-like structures were also obtained. The investigation of the selfassembly process of such peptide bolaamphiphiles can give further insight into the dynamics of formation of various
supramolecular nanostructures. The materials formed were found to be highly stable and were examined for utilization as
scaffolds for biomaterials. Biopolymer chitosan/ phenylalanine functionalized nanotubes were successfully prepared. The
morphology and properties of the chitosan/Phe-nanotubes were characterized by transmission electron microscopy (TEM),
optical microscopy (OM) and X-ray diffraction (XRD). The nanotubes were dispersed throughout the chitosan matrix.
Their water sorption behavior and the effect of chemical composition on the extent of water uptake were also evaluated.
18) G
Linking the diversity and activity of diazotrophs across a gradient of agricultural disturbance
Daniel H. Buckley, Shi-Fang Hsu, and Tyrrell Nelson
Cornell University, Ithaca, NY
A diversity of free-living nitrogen fixing organisms can be revealed in soil through analysis of nifH genes and many of
these diazotrophs belong to sequence clusters that do not contain any cultivated isolates. These noncultivated diazotrophs
remain poorly characterized and their contributions to soil nutrient cycles have yet to be determined. In this research
project, we studied nifH diversity across a gradient of agricultural disturbance to understand how changes in the soil
environment impact the diversity and activity of noncultivated diazotrophs. The experimental site is located in Chazy, New
York and was established in 1973. Soil samples were taken from two different depths (0 - 5 cm and 40 -50 cm) and the
diversity of the diazotoph community was determined in these soils by sequencing of nifH sequences. N-fixation rates and
soil characteristics were determined to evaluate linkages between community composition, environmental characteristics,
and the activity of diazotophs in soil. Soil cultivation was associated with a marked reduction in the diversity of the
diazotroph community. One group of noncultivated diazotrophs occurred only in soils that had never been cultivated. This
noncultivated group represented 56% of the nifH genes recovered at the surface but less than 1 % of the nifH genes
recovered from deeper soil. Both soil cultivation and soil depth have significant impacts on a range of soil variables. Nfixation rates were also affected by soil cultivation but were not significantly correlated with soil characteristics at the site
suggesting that diazotroph community composition may influence nitrogen fixation in soil.
19) U
Peptide folding Dynamics and their Interactions with Nanovesicles
Melanie P. Dabakis, Robert Tamayev, and Ipsita A. Banerjee
Chemistry Department, Fordham University, Bronx, NY
Misfolding of proteins leads to insoluble protein deposits, which eventually causes neurodegenerative diseases such as
Alzhiemers and Parkinsons. We are investigating the molecular basis of peptide aggregation and protein deposition. The
transformation process from -helices to -sheet structures appears to play a major role in the fibril formation and
aggregation of such peptides. In addition, their binding properties with metals and other proteins are considered to play a
significant role, in particular because there is an abundance of heavier metal ions in brain tissue. In lieu of this, we have
studied the binding properties of -amyloid and -synuclein peptides with Pd, Ni, Cu, and Au ions. In addition to metal
ions, in order to shed light into the mechanism of aggregation, we have also examined their interactions with synthetic
peptide nanovesicles as a function of pH, and solvent polarity. The interactions of aggregating systems such as -synuclein,
and various fragments of the -amyloid peptide with metal ions as well as peptide nanovesicles were studied using atomic
force microscopy, circular dichroism, transmission electron microscopy, zeta potential measurements, dynamic light
scattering and infra-red spectroscopy. Our studies reveal that at certain pH, the -synuclein can bind to the nanovesicles
leading to a reduction in fibril formation. Thus, in this work, we introduce a peptide model based study using peptide
nanovesicles, providing a simple system which can be used for a systematic study for the impact of secondary structure
transformation at the molecular level.
20) U
The Relationship between infant temperament and spontaneous eye blinking (SB)
Kara Wallace, Jose Valdez, Bethany Leece, Krista Cunningham, Linda Poole, and Leigh F. Bacher
Department of Psychology, SUNY Oswego, Oswego, NY
Compared to adults, infants spontaneously blink (SB) at very low rates. The mechanisms underlying the developmental
increase in the rate of SB, the wide individual differences, and the malleability of SB rate are not understood. Some
researchers assert that differences in dopamine (DA) function underlie differences in temperament. We investigated SB as it
relates to temperament. Forty 12 mo. infants (20 F) were observed during a quiet baseline (5 min), a stimulus phase (6
min), and three temperament tasks. In the first task, the infant was offered three toys by the experimenter, followed by a
“stranger”. The next task tested the infant’s willingness to approach novel objects by presenting 6 (3 low stimulus and 3
high stimulus) toys. The final task assessed infants’ problem solving by blocking a toy with Plexiglas (barrier task). Parents
completed the IBQ-R. Individual differences in SB were wide: 0.7 - 8.7 blinks/min. No sex differences were found in
background variables. Sex differences were found in baseline SB rate with females exhibiting higher SB rates (M = 5.6
±1.7) than males (M = 3.6 ± 1.9), t (38) = -3.40, p = .002, and in various latencies to approach objects. Relationships
between SB rate and temperament were also found. Sex differences could be explained by an unrepresentative sample or
that girls may be showing acceleration in the mechanisms that may be responsible for increasing SB from infancy to
adulthood. The relationships observed between SB and temperament may suggest that SB could be associated with
inhibitory tendencies.
21) U
Characterization of Photoreceptors Cell Types in Myotis lucifugus
Rashna Clubwala, Jonathan Hureau, and Kristy L. Kenyon
Hobart and William Smith Colleges, Geneva NY
Previous research has demonstrated that Myotis lucifugus bats express an opsin pigment that allows for ultraviolet light
detection. Although molecular studies suggest that bat eyes contain photoreceptor cells capable of color vision, relatively
little is known regarding the overall topography of the adult bat visual system. The technique of immunofluorescence was
used to examine the cellular architecture of bat retinal tissue. The localization of opsin protein expression revealed
photoreceptor subtypes in adult bat eyes. This project provides further insight into the functioning of the visual system of
bats and other related species.
22) U
Identification of Genetic Markers for Amur-Bengal Tiger Hybrids
Tiffany Scharadin and Amy B. Welsh
Department of Biological Sciences, SUNY Oswego, Oswego, NY
Amplified fragment length polymorphism (AFLP) techniques will be used to find loci that are specific to either the Amur
or Bengal tiger subspecies. These definitive loci are then analyzed on samples from tigers being housed at a refuge to
identify if the tiger is a hybrid. Purebred tigers are crucial to maintain the high level of genetic diversity in their species
survival program. A specific marker of hybridization would be an easy way to identify a hybrid and remove it from the
captive breeding program. Ideally, genetic analysis of subspecies will be more accurate than identification based on
morphological traits.
23) U
A Novel Synthetic Extra-Cellular Matrix for Cartilage Tissue Engineering
Gwen Owens
Department of Biomedical Engineering, Cornell University, Ithaca, NY
In this study, growth factor binding found in natural extra-cellular matrix (ECM) was mimicked by a modified polymer
scaffold which could attract Insulin-Like Growth Factor-I (IGF-I), a growth factor known to stimulate ECM production by
chondrocytes, and Transforming Growth Factor-β1 (TGF-β1), a growth factor known to induce chondrogenesis in
mesenchymal stem cells. Short peptides sequences were synthesized and covalently attached to an alginate polymer
scaffold. Using this model, affinity of each growth factor for its respective synthetic peptide was quantified via Surface
Plasmon Resonance (SPR), and the density of peptides bound to alginate was determined using Attenuated Total
Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR). Through these novel peptides, growth factors are
specifically and non-covalently retained by the alginate, allowing for controlled release of growth factors to enhance
production of mechanically functional, clinically useful cartilage tissue.
24) U
The comparative effects of levaquin, ciprofloxacin, and ofloxacin
Christine Stathes
Dominican College, Orangeburg, NY
Antibiotics are chemicals produced and secreted by microorganisms that can inhibit or destroy the growth of pathogenic
microorganism, often by altering an essential metabolic pathway. To be effective in human medicine, ideally they should be
nontoxic to the human host, and should discourage the formation of microbial strains resistant to antibiotics. In order to test
bacteria against antibiotics the Kirby-Bauer method was used. The antibiotics levofloxacin, ofloxacin, and ciprofloxacin
were made through serial dilutions to the concentrations of 0.0025 mg/ml; 0.00025 mg/ml; 0.000025mg/ml for levofloxacin
and ciprofloxacin, and 0.0030 mg/ml; 0.00030 mg/ml; 0.000030 mg/ml for ofloxacin. Filter disks were then soaked in these
dilutions then transferred to the confluent lawn cultures of Escherichia coli and Staphylococcus epidermidis followed by a
48 hr incubation period at 37ºC. These antibiotics were being tested against, gram negative bacteria, E-coli, and a gram
positive bacteria, Staphylococcus epidermidis. This experiment was used to test which of the antibiotics was more effective
on a gram negative or gram positive bacteria.
25) U
A comparative study of Quantum dot versus traditional immunofluorescence in the detection of
Bat Retinal Cell Types
J. R. Hureau, R. Clubwala, and K.L. Kenyon
Hobart and William Smith Colleges, Geneva, NY
This research project was aimed towards gaining a better understanding of bat vision, a relatively new area of investigation.
Previous work in this field indicates that bats such as Myotis lucifugus are capable of color vision. Yet, few studies have
documented the overall organization of the bat visual system. One aim of this study was to use antibodies to characterize
different retinal cell types (amacrine, ganglion and photoreceptors) in adult bat eyes. Additionally, we also investigated the
use of Quantum dot technology for immunofluorescence. We compared Quantum dot labeled antibodies to those labeled
with traditional fluorophores to determine the advantages of using Quantum dots for labeling multiple proteins within cells.
26) U
Promotion focus fits openness to experience; prevention focus does not
Nathaniel Baum, Lisa Schlessinger, Jennifer Rodgers, Jessica Nuzzetti, Bernis Ozses, Christine Dosch, Adam Weber,
Christine Klemann, Jolie Baumann, Colin Flynn, Audrey Harkness, Melissa Ball, Emily Clark, Rebecca Ramirez, and
Leigh Ann Vaughn
Ithaca College, Ithaca, NY
Regulatory focus theory (e.g., Higgins, 1997, 1998) distinguishes between two regulatory foci: prevention and promotion.
An increasingly detailed picture is emerging about the characteristics of people in each regulatory focus. The purpose of the
current research was to examine how these regulatory foci relate to the broader structure of personality, the so-called “Big
Five” personality factors. People in a prevention focus and those low on Openness to Experience generally tend to show an
aversion to risk and relatively low creativity. By contrast, people in a promotion focus and those high in Openness to
Experience tend to show a relative tolerance for risk and more creativity. In two studies we examined how well prevention
and promotion foci fit each of the Big Five personality factors. We predicted and found that promotion focus relates to
higher Openness and prevention focus to lower Openness. In one study, we measured the Big Five personality factors using
the 44-item Big Five Inventory (Benet-Martinez & John, 1998). Then we asked participants to think about either five
(promotion-consistent) hopes or five (prevention-consistent) duties, and to report their motivation to achieve each goal. We
found that Openness was positively associated with motivation to pursue hopes and negatively associated to pursue duties.
In the second study, we experimentally varied whether participants reported their hopes, duties, or “goals,” then we
administered a state version of a 10-item Big Five scale (Gosling, Rentfrow & Swann, 2003). Participants assigned to list
hopes scored higher on Openness than participants assigned to list duties.
27) U
Promotion focus fits elated mood, and prevention focus fits depressed mood
Jolie Baumann, Christine Klemann, Adam Weber, Jessica Nuzzetti, Christine Dosch, Jennifer Rodgers, Lisa Schlessinger,
Colin Flynn, Nathaniel Baum, Bernis Ozses, Emily Clark, Audrey Harkness, Rebecca Ramirez, Melissa Ball, and Leigh
Ann Vaughn
Ithaca College, Ithaca, NY
Typical information processing styles seen among people in a depressed or elated mood are quite similar to those of people
in a prevention focus or a promotion focus, respectively. People in a depressed mood and people in a prevention focus
generally tend to engage in careful, detail-oriented thought, show an aversion to risk, and avoid playful exploration of
creative solutions (Schwarz & Bohner, 1996). By contrast, people in an elated mood tend to use general knowledge
structures in pursuing goals (Bless et al., 1996), show a tolerance for risk, and engage in playful exploration of creative
solutions (Schwarz & Bohner, 1996). People in a promotion focus tend to use strategies of goal pursuit that are general and
broad, show a relative tolerance for risk, and arrive at more creative solutions. The purpose of the current research was to
examine whether an elated mood fits a promotion focus on ideals, and a depressed mood fits a prevention focus on
“oughts.” Regulatory fit should enhance the perceived value of goal pursuit (Higgins, 2006). Thus, compared with people
who experience regulatory nonfit when considering a future goal (depressed mood/ideal goal, elated mood/ought goal)
people who experience regulatory fit (depressed mood/ought goal, elated mood/ideal goal) should (1) value that goal more,
(2) imagine feeling more grateful for help with that goal, and (3) imagine feeling angrier if someone impedes their progress
toward that goal. Three experiments that manipulated mood and the regulatory focus of imagined goals demonstrated
support for these hypotheses.
28) U
The role of ease in mental transportation via narratives
Colin Flynn, Bernis Özses, Christine Dosch, Christine Klemann, Nathaniel Baum, Adam Weber, Lisa Schlessinger,
Jennifer Rodgers, Jessica Nuzzetti, Jolie Baumann, Rebecca Ramirez, Emily Clark, Audrey Harkness, Melissa Ball, and
Leigh Ann Vaughn
Ithaca College, Ithaca, NY
We are surrounded by narratives: stories in which the main character(s) encounter and resolve difficulties. Narratives can
be quite influential –and they are more persuasive and enjoyable the more they transport readers into the story world (Green
& Brock, 2000; 2002). Generally speaking, the easier it feels to imagine story events, the more transporting the story should
be. Numerous things, besides the story itself, could affect how easy it feels to imagine it. One of those things could be the
font in which the story is written. If the story is good, a clear font should enhance transportation through enhancing the ease
of reading the story and enhancing how confidently one responds to story events. That effect should go away, however, if
readers sense that the font is the only reason why it feels easy to read the story. Additionally, if it feels easy to read a story
that is not very good, one should be less transported by it, and become more certain that it is not a good story. Two
experiments subtly manipulated the clarity of stories’ font. Additionally, one experiment led some participants to attribute
feelings of ease to the font; participants were more transported by the story unless we explicitly drew their attention to the
clarity of the font. The other experiment instead presented some participants with a good story, and others with a not-sogood story. Those who read the good story in the clearer font were more transported; the reverse occurred with the not-sogood story.
29) G
An RNAi based screen for genes involved in the development of the arbuscular mycorrhizal
symbiosis
Janelle Jung, Jeon Hong, Steve Gantt, Colby Starker, and Maria Harrison
Boyce Thompson Institute of Plant Research, Ithaca, NY
The arbuscular mycorrhizal symbiosis (AMS) is a symbiotic relationship formed within a plant root system between soilborne fungi of the order Glomales and more than 80% of the world’s flowering plant species. As obligate biotrophs,
arbuscular mycorrhizal (AM) fungi are completely reliant on host plants as their sole carbon source, in return assisting the
plants with the uptake of phosphorus and other limiting mineral nutrients. The arbuscular mycorrhizal symbiosis develops
in the roots, where the AM fungus colonizes the root cortex. The fungus produces arbuscules, specialized, highly-branched
hyphae, within the cortical cells. These arbuscules are the interface of phosphate delivery to the plant. The AM symbiosis
has a significant impact on plant mineral nutrition and is important in ecosystems throughout the world, little is known
about the molecular basis underlying its development and regulation. Here we present our method for identifying the plant
genes involved in the symbiosis by means of an RNAi based screen for abnormal colonization phenotypes in hairy root
transformants of the model legume Medicago truncatula.
30) U
Lipophilic Cations: Synthesis, Analysis, and HPLC of Novel Arylphophonium Salts
Dennis Bennett and J.C. Williams, Jr.
Rhode Island College, Providence, RI
Arylphosphonium salts have shown some promise as novel anti-cancer agents. These salts tend to accumulate in the
mitochondria of malignant cells in vitro, but getting the salts into cells in vivo has proven challenging. They are also
bactericidal, and they inhibit acetylcholinesterase. We report research involving the development of new techniques for the
synthesis of these salts and methods of analysis of the compounds in vitro. We have demonstrated a three-step synthesis,
two of which are performed in the same vessel, with overall good yields. We report other methods of synthesizing this type
of compound which will allow an increase in the diversity of our library. The logP values of the compounds have been
calculated by QSAR and obtained from measured partition coefficients and HPLC data. LogP values are primary physical
predictors of drug absorption. These can be determined UV-Vis absorbance measured in both layers in a water-octanol
partitioning experiment, but this is time and labor-intensive. An alternative method is to use calibrated HPLC retention
times to calculate these values. We report the application of a newly available column, Waters AT-3, to determine HPLC
logP values for a set of these compounds.
31) U
DNA interaction and bacterial toxicity of aryl phosphonium salts
Luis D. Munoz, Nicole E. DeRoy, John C. Williams, and Karen H. Almeida
Rhode Island College, Providence, RI
Aryl phosphonium salts (P+) exhibit both lipophilic and cationic character, making them ideal phase transition catalysts. As
such, they have been found to accumulate preferentially in tumor cells due to the high membrane potential of tumor
mitochondria. Additionally, this class of compounds interacts directly with DNA presumably due to electrostatic attraction
to the negatively charged DNA backbone. Thus, aryl (P+) salts may be developed as a template for anti-cancer drugs that
target mitochondrial DNA. Compounds purchased from Aldrich and ones newly synthesized in our labs were used to
evaluate DNA interactions. The substituents on the P+ may alter the steric environment surrounding the positive charge and
suppress electrostatic binding. Initially, molecular mechanic calculations were done to determine possible interactions with
DNA. Computational analysis was corroborated by DNA retardation analysis, using agarose gel electrophoresis. DNA
binding to a given compound appears to be a function of the accessibility of the positive charge, with the most sequestered
P+ being in tetraphenylphosphonium bromide, which shows no interaction with DNA in vitro or in silico. Molar binding
ratios were calculated to evaluate the intensity of these interactions. Finally, compounds were screened for toxicity in E.
coli. Preliminary results suggest that bacterial toxicity of aryl P+ salts is dependent on DNA binding although not
exclusively. Future studies will determine the relationship between DNA interaction and bacterial toxicity by screening
bacterial mutants deficient in known DNA repair proteins.
32) U
TGF-1-stimulated Transactivation of the EGF Receptor is Required for PAI-1 Expression
Christina Cervone, Stacie Kutz, Jennifer Freytag, and Paul Higgins
Russell Sage College and Albany Medical College, Albany, NY
Migration of epithelial cells requires the regulated degradation of the extracellular matrix by a complex cascade of
proteases and their respective inhibitors. Of particular interest, expression of plasminogen activator inhibitor 1 (PAI-1), a
member of the serine protease inhibitor (SERPIN) family, has been shown to be necessary for migration of keratinocytes
during wound repair, is required for transition from benign to squamous cell carcinoma in cutaneous cancers, and correlates
with poor prognosis of cancer patients. Previous research has demonstrated that two growth factors, TGF-β1 and EGF,
cause increased expression of PAI-1 and that possible crosstalk occurs between the activated signaling pathways. This
study focused on MEK/ERK signaling and showed that inhibition of this pathway blocked PAI-1 expression and reduced
wound closure in keratinocyte monolayer cultures. One signaling interaction investigated was the TGF-β1-stimulated
transactivation of the EGF receptor (EGFR). Inhibition of EGFR kinase activity resulted in reduced PAI-1 expression and
reduced phosphorylation of ERK in TGF-β1-stimulated cells. Moreover, inhibition of MMP activity also decreased TGFβ1-induced PAI-1 expression and ERK activation, suggesting a requirement for EGFR ligand release from the extracellular
matrix. In mouse embryo fibroblasts (MEFs) lacking the EGFR there was no induction of PAI-1 following stimulation;
however, MEFs with wild type EGFR showed TGF-β1-stimulated PAI-1 expression. Furthermore, growth factor-induced
wound closure was significantly enhanced in wild type versus EGFR-null MEFs. These results suggest a ligand-dependent
EGFR transactivation following TGF-β1 stimulation is necessary for maximal PAI-1 expression. Refining current
knowledge of the signaling pathways involved in PAI-1 gene regulation may lead to the development of cancer therapeutics
to target these pathways and impair cancer cell invasion.
33) U
Liphophilic Cations: Computational Analysis of Arylphosphonium Salts Bound to DNA
Gabriel Rodriguez and J. C. Williams Jr.
Rhode Island College, Providence, RI
The potential for differential binding of DNA by charged aryl-substituted molecules drives the formation of a chemical
library consisting, in this instance, of arylphosphonium salts conjugated to hydrophobic or hydrophilic moieties. These salts
have been shown by molecular mechanics calculations to interact with DNA by intercalation, minor groove binding, major
groove binding, or a combination of the three. The same molecules induce shifts of the melting temperature of native DNA
and exhibit binding to DNA in gel electrophoresis. The propensity for either type of interaction is dependent on the
structure of the molecule, they show structure activity relationships. Synthesis of new examples of these compounds is
reported. Tris (4-methoxyphenyl) phosphine was bound to long-chain hydrocarbons and urea by the linker toluic acid as the
arylphosphonium salt ester by making the salt with ▒-bromotoluic acid followed by esterification. NMR, IR, MS, and
HPLC were used to anaylize the results. The computational analysis was done using HyperChem MM+ and AMBER to test
for binding affinities and geometries of the constructed molecules to DNA of various 24-base pair sequences (G-C rich, AT rich, A-T/G-C mishmash). The molecules’ ability to enter a cell, the mitochondria, and the nucleus in conjunction with
the possibility of sequence specific DNA binding has implications for possible pharmaceutical applications.
34) U
Male type and age as a factor in vocal consistency in mocking birds (Aves: Mimidae)
Rachel Rossman and Carlos A. Botero
Cornell University, Ithaca, NY
While many studies have looked at selection for large repertoires sizes in birds, few have explored the potential for
selection on the ability to sing each type in the repertoire appropriately. We explored this issue by studying the consistency
with which two closely related species of mockingbirds, i.e. the northern (Mimus polyglottos) and the tropical mockingbird
(M. gilvus), repeated each syllable type. We hypothesized that if there is selection for singing ability and not just for an
increase in repertoire size, it could be expected that syllable consistency should be (1) higher in the species with higher
potential for sexual selection via female choice (i.e. higher in the northern versus the tropical mockingbird), (2) higher in
males expected to be of higher quality (i.e. in dominant versus subordinate birds) and (3) higher in older, more experienced
individuals. We found that song consistency could be improved through practice because tropical mockingbirds became
more consistent with age. When comparing across male types, we found that consistency was higher in northern and
dominant tropical mockingbirds than in subordinate tropical mockingbirds (although our data suggest that dominant
tropical mockingbirds that compete with subordinates for breeding may not be much better singers than these subordinates).
We suggest that the lack of significant differences between northern mockingbirds and dominant tropical mockingbirds
could be a product of a trade-off between repertoire size and singing consistency because as the number of types in a
repertoire increases, the opportunities to practice each type are reduced.
35) U
Lipophilic Cations: Aryl Phosphonium Salt Esters
Lisa Chin and J.C. Williams, Jr.
Rhode Island College, Providence, RI
Aryl phosphonium salts, APS, are attracted to the mitochondria of malignant cells, thus making them potential anti-cancer
agents. Malignant cells are more negatively charged than normal cells due to their increased rate of metabolism. This
creates a large charge gradient between the interior and exterior of the cell wall. APS are positively charged making them
very attracted to the negatively charged malignant cells. Due to the steep charge gradient the APS is drawn into the cell.
Once inside, the APS can interact variably with DNA according to its size and structure. This interaction can be modeled by
molecular mechanics calculations and shows intercalation, electrostatic interactions, and minor groove binding. Synthesis
of alkyl esters of APS is done in three steps with good yield. Triphenylphosphine and alpha-bromo-para-toluic acid are
heated with toluene to precipitate salts. These are chlorinated by heating in neat thionyl chloride, and esterified by reaction
with an alcohol. After precipitation in diethyl ether, the solid is isolated and vacuum dried. Melting point, IR, NMR, UVVIS, HPLC, and LC/MS are used to verify APS structures. The compounds are then screened against bacteria, cells in
culture, and DNA in vitro.
36) U
Seed weight and germination of the rare plant Desmodium cuspidatum and two common
Desmodium species
Senack, L., Skogen, K.A., and Holsinger, K.
Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, CT
Desmodium cuspidatum (Fabaceae) has experienced a decline in New England since at least 1976, while populations
elsewhere in the country are not known to have declined. However, little is known about the germination requirements of
this and associated common Desmodium species. Using seeds from Desmodium cuspidatum and two related Desmodium
species (D. glutinosum and D. paniculatum), a germination experiment was conducted to determine whether germination
rates differ among the common and rare species across three seed treatments and two soil treatments. Germination rates for
the declining species, Desmodium cuspidatum, were lower than those of the other two species across all seed treatments.
However, differences were found in germination rates within species across seed treatments. Soil treatment did not have a
strong effect on germination rates. The results of this experiment will provide important information that can be used to
inform the management of Desmodium cuspidatum and may have broader implications for other related legumes. Funding
was provided by the University of Connecticut’s Summer Undergraduate Research Fund.
37) U
Computational Evaluations of Metal Replacement and Charge Transfer in Xeroderma Pigmentosum Group A
(XPA)
Christopher Latendresse, Angela Dauphinais, and Glanisson de Oliveira
Physical Sciences Department, Rhode Island College, Providence RI
Xeroderma Pigmentosum Group A (XPA) protein is part of the Nucleotide Excision Repair (NER) pathway for removal of
bulky DNA lesions. The zinc finger of XPA is the site that binds to DNA, triggering a series of reactions that eventually
rids the DNA of its lesions. The mechanism used by XPA to identify damaged DNA is not well known. It has even been
suggested that XPA not only identifies damaged DNA, but it may participate in the repair very directly, affecting charge
transfer by absorption of electrons from damaged DNA or by blocking the transfer of charge down the DNA backbone.
Metal replacement studies in XPA may elucidate the catalytic mechanism. Cadmium in particular is a carcinogenic heavy
metal that is known to inactivate the protein thereby leaving damaged DNA vulnerable to permanent mutations (thus
cadmium is carcinogenic). In this study, we examine the electron affinities of XPA complexes under varied conditions, in
order to evaluate the likelihood that XPA is directly involved in charge transfer and to verify the effect of cadmium
substitution in the zinc finger structure. Our calculations involving reduced models of the protein metal center suggest that
XPA does not absorb electrons from DNA, and that is not surprising. Additionally, our simulations are in agreement with
experimental results that show a reversible reduction of the cadmium complex. Perhaps most interestingly, our results
indicate that a significant structural change occurs in XPA concomitantly with the reduction of cadmium. This effect has
been heretofore unreported by other groups.
38) U
Photoacoustic Infrared and Raman Spectroscopic Analysis of Inorganic Pigments
E.L. von Aderkas, M.M. Barsan, D.F.R. Gilson, and I.S. Butler
McGill University, Montreal, Quebec, Canada
Inorganic pigments have been used in artworks for thousands of years. Such compounds have been employed in decorating
prehistoric cave walls and pharaoh’s tombs. This class of pigments, which contains such materials as azurite, cobalt blue
and ochre yellow, was selected and investigated because of its lengthy history of use in Western European art. In recent
decades, art conservation practices have placed an increasing emphasis on spectroscopic techniques. These analytical tools
are often used for artwork dating, discovery of forgeries, restoration and conservation of cultural heritage. The field of art
conservation requires sensitive and non-destructive instrumentation in order to treat a particular work properly. The unique
characteristics of photoacoustic infrared spectroscopy (PAS), namely, increased sensitivity, non-destructivity, minimal
sample preparation and depth-profiling capacity suggest it is an ideal technique for art forensics. Surprisingly, however, this
technique has remained unexplored. Initially, the selection of inorganic samples was analyzed using the well-established
Raman microprobe spectroscopic technique in order to verify the identity of the purchased pigments. The samples were
then analyzed using a MTEC photoacoustic cell attached to a Nicolet Fourier transform infrared spectrometer. The spectra
obtained demonstrated impressive reproducibility. To examine the applicability of PAS to the art analysis sphere, a
homemade “fresco” was constructed using plaster of Paris, and the freshly painted pigments situated on the fresco surface
were characterized. This research demonstrated that photoacoustic infrared spectroscopy is an effective and reliable
technique suitable to the field of art analysis.
39) U
Liphophilic Cations: Synthesis and Toxicity of Arylphosphonium Salts Conjugated to
Hydrocarbons and Ureas
Sean P. Hersey and J. C. Williams, Jr.
Rhode Island College, Johnston, RI
Arylphosphonium salt-lipid conjugates have been shown to bind DNA, kill certain bacterial strains, inhibit
acetylcholinesterase and are selectively taken up by malignant cell’s mitochondria. Triarylphosphines were reacted with
alpha-bromo-p-toluic acid in refluxing toluene to form salts. Reaction progress was followed using TLC, and product
identification was done by IR, MP (> 250), and physical appearance (pure white solid). Thionyl chloride was added to this
product, and the reaction progress followed by IR in which loss of the OH peak and appearance of the C=O peaks
characteristic of the acyl chloride was observed. Quantitative conversions were routinely observed. In the same vessel,
after removal of excess thionyl chloride, an alcohol or amine was added in excess or in a 1:1 molar ratio and the mixture
stirred at room temperature overnight. The products are isolated by precipitation with diethyl ether and vacuum drying. The
conjugates of urea and N-methylnitrosourea (MNU) were prepared by this method using DMF as the solvent. The reaction
was first heated gently for a half hour and allowed to stirred overnight. Vacuum distillation at 0.1-.5 torr was preformed to
remove excess DMF. Crude product was recrystalized from ethanol. IR, NMR, MP, HPLC, and MS verified formation of
the desired products. The same reaction was repeated using N-Nitroso-N-Methylurea instead of urea and the product
isolated. MNU is a known DNA alkylator and arylphosphonium salts bind DNA. The bactericidal activity and cell toxicity
of these compounds was determined. The former showed significant structure activity relationships.
40) U
Bloom syndrome protein: partnerships to maintain genomic stability
Eileen L. Murphy, Kerri L. Gulley, Krystal L. Bergeron, Lily Brown, and Karen H. Almeida
Rhode Island College, Providence, RI
Bloom Syndrome (BS) is a rare recessive disorder resulting from genetic mutation of the Bloom Syndrome gene (BLM).
BS patients exhibit a wide range of cancers and consequently an early death. The criterion for BS diagnosis is an increased
frequency of sister chromotid exchange (SCE), events that serve as markers of genomic instability. Thus, BLM, a DNA
helicase, is involved in suppressing genomic instability. BLM interacts physically with Rad51, the central player in
homologous recombination, excess activity of which also destabilizes the genome. The goal of this research is to
investigate the physical and functional characteristics of the BLM-Rad51 interaction. To evaluate and characterize the role
of BLM in genome stability, we cloned full length BLM engineered as a fusion protein with affinity tags on the N- and Ctermini. Additionally, we have developed mutants of BLM in which defined portions of the termini have been removed.
Production and purification of these proteins will allow biochemical analysis of BLM partnerships with repair proteins such
as Rad51. Expression of BLM from the T7 promoter proved toxic, both in E.coli and Spodoptera frugiperda insect extracts
(Qiagen), generating only an N-terminal degraded product. Expression of BLM from mammalian cells under a CMV
promoter followed by immunoprecipitation of protein is currently underway. Preliminary data of the DNA protein analysis
confirms both the RecA- and the Rad51-ssDNA interaction.
41) U
Peripheral Refractions of Myopic Young Adults
Kenneth L. Angelino and Howard C. Howland
Neurobiology and Behavior Department, Cornell University, Ithaca, NY
Recent work of Smith et al. (2005,IOVS 46(11)3965) has raised the possibility that human myopic progression is driven by
the relative hyperopia of the peripheral retina. We wished to determine if the peripheral retinas of young adult myopes were
in fact hyperopic relative to foveal refraction, and also measure oblique astigmatism in our subjects. We used a Power
Refractor (Multichannel systems, Reutlingen Germany) to refract 13 non-cyclopleged subjects (age: 18-19 years) who
viewed a tangent screen at 1 meter distance. Nine of these subjects were myopic. Eight fixation targets were arranged
around a 25 degree circle and another eight around a concentric 15 degree circle with the power refractor in the center.
Individual cylinder axes at eccentric points were correlated with expected axes of oblique astigmatism. The mean difference
between central and peripheral refractions for the 25 degree and the 15 degree eccentricities of both eyes of the 9 myopic
subjects showed peripheral hyperopia that was not significant (p = 0.075). However, good correlations between the
predicted axes of oblique astigmatism and the measured axes were obtained for all 13 subjects (mean correlation coeff =
0.82, mean p = .0005). From our data it appears possible that the progression of human myopia is driven by a hyperopic
peripheral refraction. Oblique astigmatism of our population was about the magnitude of that found in the Indiana
Chromatic eye (Wang & Thibos, 1997, Opt & Vis Sci 74(7)557), and is well represented (r 2 = 0.993) in the range studied
by the equation: Interval of Sturm [D] = 0.00422 * a2 , where "a" is in degrees.
42) U
Developing Situational Awareness in a Young Bilingual Child: A Hebrew-English Case Study of
Balanced Exposure
Kristen Pallonetti, Julia Rosenberg, Erica Shreck, and Brian Druyan
Cornell Language Acquisition Lab, Ithaca, NY
The present study evaluates the English second language acquisition of a three-year old child who emigrated from Israel to
the United States in August 2006, after being exposed only to Hebrew since birth. Enrolled in a full-day pre-k program,
this child had been exposed to English beginning in late August, until the present in school, but maintained Hebrew at
home. One of the mysteries of second language acquisition in the young child is: how does a child differentiate two
languages, while acquiring them simultaneously? What factors effect this awareness of both languages? Does diverse
exposure aid or hinder the language acquisition process? In this project, we pursue an answer to these questions. To gather
the necessary data, experimenters conducted sessions in both Hebrew and English with the child at school and at home
(over a seven month period, aged 3.1 to 3.8), following from first exposure to English. In these videotaped sessions,
experimenters spoke with the child to elicit natural speech in each language through conversation and play. Specifically
designed questionnaires were administered to the child's parents and teachers. While the child's English acquisition was
found to proceed significantly over these months, at the same time, the development of the child's meta-linguistic
situational awareness was found to proceed in four distinct stages over the seven month period. Several factors were found
to influence this developing awareness. This study on early childhood bilingualism provides evidence on how second
language learning through immersion in a balanced exposure (consistent home and school settings) aids in rapid learning
and growth. We discuss these results in terms of the cognitive benefits of bilingualism.
43) U
Field Determination of Age in Northern Short-tail Shrews (Blarina brevicauda) at Rice Creek
Field Station, SUNY Oswego
Sara Ressing and B. Diane Chepko-Sade
Department of Biological Sciences, SUNY Oswego, Oswego, NY
Long term longitudinal studies of shrew populations such as that by Getz et al., (2004) lack a demographic component due
to the difficulty of accurately determining the age of living shrews. In this study we test the validity of using incisor length,
an easily measured characteristic of living shrews, as an aging criterion. Relative age of skeletonized specimens can be
estimated by microscopic examination of the wear pattern on the occlusal surface of the molars and third premolar; older
animals show greater tooth wear than younger specimens (Pearson, 1945). Unfortunately, this method is impractical for
repeated examinations of living specimens. Pruitt (1954) further characterized Pearson’s six age classes according to order
of wear on specific cusps. We classified the dentition of over one hundred skulls of northern short-tailed shrews (Blarina
brevicauda) at SUNY Oswego’s Rice Creek Field Station according to Priutt’s age classes. We measured length of the
pigmented portion of the upper incisor of the same specimens without reference to molar wear, and then compared the two
criteria using Pearson’s correlation coefficient. There was a highly significant relationship between incisor length and tooth
wear class (p < 0.0001), suggesting that length of the pigmented portion of the upper incisor is a reliable field indicator of
age in B. brevicauda. Using mark and recapture methods, it will not only be possible to add age categories to crosssectional descriptions of populations, but also to develop a more complete picture of the life histories of this species using
longitudinal information on individuals.
44) U
Investigation of Connexin Genes GJB2 and GJB6 for Potential Involvement in the development
of Presbycusis
Aziana Ismail and Dina L. Newman
Rochester Institute of Technology, Rochester, NY
Presbycusis, or age-related hearing loss, is a hearing disability due to deterioration within the ear commonly found among
old people. Although no genes are yet known to cause presbycusis in humans, many genes are implicated in various forms
of congenital deafness. Mutations in gap junction genes GJB2 (connexin 26) and GJB6 (connexin 30) are the most common
cause of nonsyndromic sensorineural hearing impairment; therefore, these genes were chosen as candidate genes for
possible role in presbycusis. We have sequenced GJB2 and GJB6 genes from 20 human subjects with presbycusis. Both
exons and 1500 bp upstream region of GJB2 have been completely sequenced in the screening set. For GJB6, all three
exons and 1500 bp upstream region have been entirely sequenced in the screening set. To date, thirteen single nucleotide
polymorphisms (SNPs, i.e. individuals differ in their DNA sequence by a single base) have been found in GJB2 and seven
SNPs in GJB6. Three SNPs (two in GJB2 and one in GJB6) were analyzed for association with presbycusis in the entire
sample set; however, no correlation between phenotype and genotypes was found. Currently, we are genotyping additional
SNPs for the entire population in order to determine whether or not variation in these genes is associated with presbycusis.
45) U
Dissection of the Thrombopoietic Transcriptome Using a Platelet Specific Microarray
S.H. Rambhia, C. Ji, L. Scudder, J. Wainer, M. Monaghan, A. Dhundale, D.V. Gnatenko, and W.F. Bahou
Dept of Hematology, Biomedical Eng., Stony Brook University, Stony Brook, NY
Human blood platelets function in wound healing, inflammation, and clot formation. Despite significant progress molecular
mechanisms of megakaryocyte maturation remain poorly characterized. We have applied a customized, platelet-specific
oligonucleotide gene chip to dissect the molecular events of megakaryopoiesis. CD34+ hematopoietic stem cells obtained
from 2 distinct adult human donors were differentiated in vitro for 21 days along the megakaryocytic lineage. Cell samples
were fixed and screened each day for one-color FACS analysis of GPIIB megakaryocyte-specific events (CD41 marker). In
parallel, a daily sample was taken for MK-isolation using magnetically labeled CD61 antibodies (MK GPIIIA-specific).
Both CD61+ and CD61- cells were processed for total RNA purification and samples were hybridized to platelet
microarrays. Filtering/analysis of microarray data revealed six genes that respond to administration of cytokines and are
differentially expressed between early and late stages of the differentiation experiment (2 fold change, p < 0.05). Of these 6
genes, MAX, surfactant (pulmonary associated protein B), and integrin ЮБ2B transcripts were significantly upregulated
between early and late stages of differentiation. While integrin ЮБ2B (GPIIB) is a known marker on platelets and mature
MKs, possible roles of the MAX protein and surfactant in MK maturation and proplatelet formation are being investigated.
46) U
Searching for the Terrestrial Paleocene/Eocene Boundary at the Canadian High Arctic: A
Carbon Isotope Study
Monica Kraus1; Advisors: Hong Yang1 and Brian Blais1; Collaborators: Ben A. LePage2 and Mark Pagani3
1
Bryant University, Smithfield, RI; 2The Academy of Natural Sciences and URS Corporation, PA; 3Yale University, New
Haven, CT
The Paleocene Eocene Thermal Maximum (PETM) is a rare climatic event in the history of the Earth, which marks the
abrupt transition from the Paleocene to Eocene of the Cenozoic era with a rapid increase in global surface temperatures of
up to 5-70C. The PETM marks the warmest climates in the past 65 million years and a world-wide negative excursion of
stable carbon isotopes (δ13C). To determine the location of the Paleocene-Eocene (P/E) boundary in high-latitudinal nonmarine strata and to examine the magnitude of vegetation and climatic change, the bulk carbon isotope ratios were
measured in coal samples taken from several well exposed outcrops at Stenkul Fiord, Ellesmere Island, Nunavut, and
Canadian Arctic Archipelago. The stratigraphic sections consist of three vertical sequences (SF-P, SF-M, and P Series) that
have an approximate total thickness of 74.27m, 73.18m, and 145 m respectively. Extending from the P-series outcrop, three
horizontal sections were taken (1, 2, and 3 Series) each spanning approximately 1 km. The δ13C in the samples ranged from
-23.9‰ to -28.7‰ with a background fluctuation of less than 2‰. The PETM boundary is placed in the upper portion of
the P-Series between P-58 and P-60 where a sharp decrease of δ13C of up to 4.7‰ is detected. This is consistent with a
recent palynological study, but differs from a previously published record from the same sequence. Because the C isotope
measurements were based upon Metasequoia-dominated plant matter, the variation of δ13C along the vertical sequence
should reflect the change of δ13C of ancient atmospheric CO2 whereas the reduced variation of δ13C in the horizontal
sequences may be due to compositional differences of ancient vegetation. This study is the first isotopically marked PETM
in high latitude terrestrial outcrops from the High Artic that provides a stratigraphic framework under which the mechanism
of drastic climatic change and its impact on non-marine environment can be further investigated.
47) U
Frequency Dependent Thermal Effects on Cardiac Electrical Stability
Ujas Shah, Harold Bien, and Emilia Entcheva
Stony Brook University, Stony Brook, NY
Cardiac electrophysiology processes are often studied at sub-physiological temperatures. Extrapolation of values is based
on Q10 (Arrhenius) model of temperature-dependence, which does not compensate for frequency deviation. We set to
quantify temperature-dependence of spatiotemporal parameters defining cardiac excitation behavior and restitution
dynamics: conduction velocity (CV), transient duration (calcium, CTD, and voltage, APD), and wavelength
(W=CV*duration). Fluorescent imaging with voltage- and calcium-sensitive dyes in neonatal rat cardiomyocyte
monolayers was employed. Normalizing to 24°C, we found strong temperature-driven increase of CV (Q10=2.44) with
smaller APD and CTD changes (Q10=1.53, 1.18). Wavelengths were less sensitive with Q10 = -1.64 (WAPD), -2.11
(WCTD).Surface plots of normalized CV as function of frequency and temperature revealed at low frequency and
temperature, CV is mostly frequency-dependent; however, as both parameters are increased, the dependence becomes
nearly equivalent. Similar analysis indicated wavelength is predominately frequency-dependent. Our results signify the
importance of examining temperature sensitivity across frequency. Finally, we examined probability for alternans at
different temperatures (theorized if rapid spiral waves (SW) rotation period, Trot, exceeds threshold period for alternans, Talt,
fibrillation is likely to occur). Our data showed Talt = 26379ms at low temperature (T L=24C) and Talt=140.8 46 at high
temperature (TH =36C). SW rotation data indicated T rot=297104ms at TL and data from L. Tung provided T rot=21723ms
at TH. Our model showed significant overlap in the distribution for Trot and Talt at TL, 75.3%, vs.16.4% (T H), increasing
likelihood for breakup at lower temperatures and revealing a potential mechanism for hypothermia-induced
arrhythmogenesis.
48) U
Vortex Dynamics: Vorticity in Stokes Flow
Mimi Tsuruga
Hunter College, New York, NY
Our goal is to draw a vortex. Helmholtz's laws of vorticity states that any particle free of vorticity will remain free of
vorticity and any particle on a vortex line will continue to move along that vortex line. Using this principle, we will find
and display vortices in fluid flow. The solutions we find in fluid dynamics are estimates of the motion of particles in a fluid.
These estimates are based on a discrete solution for the Navier-Stokes equation. Our context is a channel with a square
obstruction in a fluid of varied viscosity. We determined the vorticities of the flow at nodal points by calculating the curl of
the vectors to draw vortex lines and vorticity level curves. By analyzing the zero-vorticity lines together with streamlines
that cross them, we established that intersection points are the inflection points of the curve of the streamlines. By changing
the Reynolds number in the Navier-Stokes equation, we can increase the viscosity in the fluid to induce a better situation
for creating a vortex.
49) U
Fighting the Stigma: Borderline Personality Disorder
Erin Pierce and Karen Wolford
Department of Psychology, SUNY Oswego, Oswego, NY
While it is well understood that the stigma of mental illness can be debilitating to a patients recovery, a pressing issue is to
investigate the methods for reducing these stigmatizing attitudes so that we may promote improved coping abilities through
more positive social functioning and interaction. A second issue with this type of research is the lack of understanding
about the impact of specific mental illness labels. This study attempts to address these issues by investigating the use of
both written and audio-visual educational information regarding borderline personality disorder on attitudes of
authoritarianism, benevolence, and social restrictiveness toward individuals diagnosed with this specific mental illness
label. Furthermore, this study addresses the use of both a pre-treatment and post-treatment measurement of attitudes, to
assess the priming affects of a pre-treatment questionnaire on attitudes. Data collection is currently in the final stages of
completion, and results for the current experiment are still pending; however, both will be completed and ready for
presentation at the time of the conference. This research will aid in better understanding the methods of reducing the stigma
of borderline personality disorder through two specific modalities of educational instruction, with the acknowledgement
that perhaps these methods may be employed in the future for improving both the patients attitudes toward the self and the
attitudes of others-in turn, improving the treatment, rehabilitation, and quality of life for these individual.
50) U
Pertussis Toxin Composite Nanofibers as a Non-Invasive Whooping Cough Vaccine
Tejas A. Gawade, Katarzyna M. Sawicka, Elizabeth J. Roemer, and Sanford R. Simon
Stony Brook University, Stony Brook, NY
Global resurgence of whooping cough, a highly contagious disease caused by the fastidious gram negative coccobacillus,
Bordetella pertussis, has raised questions of the current preventative and treatment technologies. A novel non-invasive
vaccine has been developed by immobilization of Pertussis Toxin (PT) in electrospun polymer (Polyvinylpyrrolidone, PVP)
nanofibers. In vitro experiments were utilized to test the bioavailability of PT inside of electrospun fibers. The sensitive
assay for PT employs Chinese Hamster Ovary (CHO) cells. CHO cells, which form an attached monolayer in their native
environment, undergo clumping in the presence of PT. The assay qualitatively measured clumping in the presence of native
PT and dissolved PT-PVP electrospun coating for varied concentrations of CHO cells. Microscopic observation showed
clumping with a sensitivity of 2.5 ng/ml of dissolved electrospun coating at 48 hours. The results of the in vitro assay
confirm retention of biological activity of PT in electrospun nanofibers. This provides a means to develop a dermal
pathway for a more effective long-term immunity against Whooping Cough. The application of electrospun coating can
provide dermally-transferred immunity against other infectious diseases, thus overtaking oral or injectable vaccines.
51) U
A Case study of Early Childhood Bilingualism: A Multifaceted Development
Aeri Lee, Lu You, Christina Yi, Zofia Stankiewicz, and Sujin Yang
College of Human Ecology, Cornell University, Ithaca, NY
Even larger than the mystery of first language acquisition in young children is the mystery of their ability to acquire more
than one language. The present study attempts to demystify the processes of bilingualism by a combined method of a
longitudinal series of experimental and naturalistic investigation. Our aim is to portray how each domain of a linguistic
system would develop in a bilingual child. We followed a four-year-old Korean-English bilingual child (MJ101602)
(acquiring English as second language) over 17 months (from 3;0 to 4;5). Our measurements were: elicited imitation (EI)
tests of syntactic knowledge of simple coordination and relative clauses (Flynn & Lust, 1980); a Peabody Picture
Vocabulary Test of lexico-semantic knowledge (Dunn & Dunn, 1997); a Pragmatics Profile (Dewart & Summers, 1995);
and the VLL Child Multilingualism Questionnaire (Yang, Blumé, & Lust, 2006). Each test allows comparison to
monolingual norms. MJ successfully reconstructs coordinate sentences, while still acquiring relative clauses, which is
similar to monolinguals. In the lexico-semantic comprehension tests, the child shows a rapid development of word
inventories from a low ranking of 23% to 84%. According to pragmatic profiles, the child displays considerable
improvement over time and many similarities with English monolinguals, although he still has more varied sentences and
greater verbalization in Korean than in English. This study suggests a normative, yet initially slow course of development
of English in a bilingual child. We discuss theoretic and empirical explanations, a specific bilingual language acquisition
pattern, and a combination of the two.
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High-Level Ab Initio Evaluations of the Hydrogen Sulfide Dimer
Gennadiy N. Berezutskiy, Thomas Watson, and Glênisson de Oliveira
Rhode Island College, Providence RI
Hydrogen sulfide (H2S) is not ubiquitous in the atmosphere, but to the extent that it is present, it contributes to the
formation of H2SO4, which is a major cause for acid rain. The study of long-range interactions of these molecules may
help to predict the onset of reaction between hydrogen sulfide and water in the atmosphere. Additionally, studying weak
interactions of H2S should allow for comparisons with water, thus shedding light on any periodic trends. Weak interactions
involving H2S are dominated by dispersion and minima on the potential energy surface for the H2S dimer are very shallow,
so it is difficult and costly to generate accurate interaction energies and structures. Extrapolating the infinite basis set limit
from a well-behaved series of bases (such as Dunning’s correlation consistent family of bases) is one way to account for
basis set effects accurately. In the case of weakly bound systems such as H2S clusters, basis set demands are even greater
than in covalently bonded systems of the same size and these extrapolations are very costly and in many cases impractical.
Recently we developed new methodology to greatly decrease the cost of infinite basis set evaluations for hydrogen bonded
systems and here we examine whether the same techniques can be applied to systems where dispersion dominates, or plays
a significant role. Basis set effects on both energetics and structure are examined. Ultimately, the basis set demands on
dispersion-dominated systems are slightly different from systems where hydrogen bonding occurs.
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Biochemical and chemical sugar detection methods
Katie Miloski and Kestas Bendinskas
Chemistry Department, SUNY Oswego, Oswego, NY
Sucrose, commonly known as table sugar, is present in natural fruits and vegetables. This disaccharide can be digested via a
hydrolysis reaction, forming glucose and fructose. We experimented with different sugar detection methods, and narrowed
down our methods to the biochemical (invertase) or chemical (HCl) digests of sucrose followed by the chemical
(dinitrosalicylic acid, DNS) or biochemical (hexokinase) detection. Biochemical methods were found to be more specific
and more expensive than the chemical methods. Results using various drinks will be presented.
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Flagella Length and Cell Size as a Function of Cell Cycle Progression in Chlamydomonas
reinhardtii
Caleb Atkins, Mark Tran, Ivonne Gomez, Rose Francois, Janice Marchut Conrad, and Peter L. Conrad
Biological Sciences, SUNY Plattsburgh, Plattsburgh, NY
Flagella of constant and equal length correlating to determined cell size (short to small and long to big) are regulated by
NIMA-kinase Cnk2p through effects on flagellar disassembly and commitment size for progression to mitosis, respectively
(Bradley et al., 2005). CC1618 (cw15, arg), B3 (an insertional mutant of CC1618) and CC3662 (lf3-2) have significant
(p<0.001) increases in both cell volume and flagella length in a light dependent manner. We measured 500-1000 cells using
ImageJ analysis of digital images for each treatment. We found that the cell volume of CC1618 nearly doubles between two
and eight hours into the photoperiod while the flagella increase in length by about 40%. B3 cell volume increased about
45% and its flagella increased by 40 % while CC3662 ( a long flagella mutant) increased in volume by about 12% and
flagella length by 29%. Phototropin is a blue light receptor that mediates various physiological responses in plants (Im et
al., 2006). Huang et al. (2004) found that C. reinhardtii possesses phototropin (flavin chromophore) in the flagella
axoneme in addition to the cell body. Previous work shows that blue light-mediated cell shrinking is inhibited by a flavin
atagonist; therefore, we investigated the role of blue light in the regulation of flagellar length.
55) U
In Vitro Characterization of Chlamydomonas reinhardtii Spectral Specific In Vivo Volume
Changes: Red Light Swelling and Blue Light Shrinking
Adam Favro, Barton Higley, Janice Marchut Conrad, and Peter L. Conrad
Biological Sciences, SUNY Plattsburgh, Plattsburgh, NY
Previous work shows that Chlamydomonas reinhardtii has a clear and spectral specific response to 660nm (swelling) and
470nm (shrinking) light that is inhibited by imidodiphosphate (IDP) and bafilomycin, respectively (Meliski et al, 2006 and
Boivin et al, 2006). Chlamydomonas reinhardtii has at least two blue light photoreceptors and no known red light
photoreceptor; therefore the photoreceptor for red light dependent swelling remains unknown although both in vivo light
responses are inhibited by a flavin antagonist (Blackmoore et al, 2003). Bafilomycin is a specific inhibitor of vacuolar H+ATPase and IDP is a specific inhibitor of vacuolar H +-PPase and the inhibition of in vitro spectral cell volume change by
these known inhibitors is specific for blue-light shrinking and red-light swelling, respectively. We characterized the
phosphatase activity of Chlamydomonas cell sonicates using ATP, pyrophosphate and polyphosphate as substrates. The
crude homogenate contains a fast component (< 5 minutes) and a slow component (> 5 minutes) using both ATP and
pyrophosphate substrates.
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Phytoremediation: A Closer Look at Regulation of Cadmium Tolerance in Chlamydomonas
reinhardtii
Elizabeth Meliski, Ian Jones, Michael Riley, Ryan Blondo, Janice Marchut Conrad, and Peter L. Conrad
Biological Sciences, SUNY Plattsburgh, Plattsburgh, NY
Cadmium, a toxic heavy metal with a long biological half life, accumulates in the environment. Chlamydomonas, a
unicellular alga, is a suggested organism to study tolerance to metals where active efflux of intracellular cadmium as well
as vacuolar, mitochondrial and chloroplast sequestration are proposed in cadmium tolerance in this organism. The
Chlamydomonas Genome Project Stress Library II evaluates gene response to different environmental conditions including
response to sub-lethal concentrations (100 μM) of cadmium. We show significant (p < 0.001) cell expansion and
accompanying cell viability of 50%, measured by fluorescein diacetate retention, for two Chlamydomonas cell wall
impaired mutants exposed to 2mM cadmium for sixty minutes in the presence of light. Under the same conditions, control
cell size remained constant. We also measured cellular response to cadmium by phototaxis and seed germination bioassay.
In plant cells, the majority of cell expansion takes place in the vacuole and previous work shows that V- H+- PPase
(vacuolar proton translocating pyrophosphatase) function is required for spectral specific cell expansion in
Chlamydomonas. Therefore, we investigated the involvement of V - H+- PPase (increased gene expression in the Stress II
library) in the cadmium response and determined if the cadmium response is light dependent.
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Programmed Cell Death or Necrosis: Chlamydomonas reinhardii Response to Respiratory Stress
Margaret Biel, Fatoumata Jobe, Amber Lachapelle, Wei Tan, Janice Marchut Conrad, and Peter L. Conrad
Biological Sciences, SUNY Plattsburgh, Plattsburgh, NY
In addition to the mitochondrial cytochrome c (cyt c)respiratory pathway, plants, algae and most fungi have an alternative
oxidase (AOX) pathway. Up-regulation of AOX transcripts, protein levels and respiratory capacity correlate with down –
regulation of the cyt c path using inhibitors such as Antimycin A as well as nitrogen source. In C. reinhardtii, nitrate was
found to upregulate AOX while ammonium had the opposite effect (Baurain et al., 2003) and Vanlerberghe et al. (2002)
show that cysteine (millimolar concentration) causes programmed cell death (PCD) in transgenic tobacco cells unable to
induce AOX due to antisense expression. Chlamydomonas reinhardtii strain H2, an insertional mutant of CC1618 (cw 15,
arg), was isolated based on its inability to grow in the presence of Antimycin A. We found that H2 cell viability, measured
by fluorescein diacetate retention, decreases after 48 hours incubation in millimolar concentration of cysteine while
CC1618 viability under the same conditions is not affected. We looked at the correlation of cell viability, in the presence of
cysteine, to agarose gel DNA analysis of identically treated H2 cells to determine death by PCD or by necrosis.
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Honeybee foragers do not reject dances for implausible locations: Reexamining the evidence for
cognitive maps in insects
Margaret K. Kirkland, Barrett A. Klein, Heather R. Mattila, and Thomas D. Seeley
Results from a previous study suggest that honey bee foragers may assess the locations advertised by dances they follow,
and reject dances for “implausible” locations that are unlikely to contain food. This work has been widely cited, and used to
suggest that bees possess cognitive maps, “insight”, and “imagination”. However, alternative explanations—other than
followers rejecting “implausible” dances—have also been proposed to explain why few recruits were observed at
“implausible” feeders. To resolve this ambiguity, we recreated the conditions of this previous study and used video data to
analyze the behavior of dance followers in the hive. We predicted that if followers actually reject “implausible” dances,
then bees following dances for an “implausible” location (a feeder in the middle of a lake) should leave the hive in response
to these dances less frequently than bees following dances for a “plausible” location (an equidistant control feeder on land).
Surprisingly, we found that bees following “implausible” lake dances were just as likely to leave the hive as bees following
control dances. Nor was there any difference in the time it took followers to leave the hive, suggesting that bees’ motivation
to leave did not depend on which type of dance they had followed. Contrary to prior findings, our results suggest that
honeybee foragers do not reject dances for locations that are unlikely to yield food. Further tests will be necessary to
determine if honeybees truly have cognitive maps, “insight”, or “imagination”, but our results offer no evidence to support
these possibilities.
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Lipophilic Cations Conjugated to Polypeptides
Sam Adediron and J. C. Williams, Jr.
Rhode Island College, Providence, RI
Arylphosphonium salt polypeptide conjugates were synthesized by solid state polypeptide synthesis (SSPS) and analyzed
by IR, NMR, MS and HPLC. SSPS consists of the coupling in sequence of amino acids to make polypeptides bound to a
resin bead. This was modified by capping the polypeptide with an arylphosphonium salt. The finished polymers were then
cleaved from the beads and isolated as solids. The process begins with swelling the polystyrene beads, which have the Cterminal amino acid bound to them, with DMF. This allows exposure of the reacting functional groups. The N-terminal is
deprotected, then reacted with the next N-protected amino acid to form a dipeptide. The process is repeated until the desired
polypeptide is synthesized. The last step couples an arylphosphonium salt to the polymer by the carboxylic acid group of a
triarylphophonium-p-toluoic acid salt. Molecular mechanics calculations of interactions with DNA showed both
electrostatic and minor groove binding. These were strongly dependent on the composition of the polypeptide part of the
molecule.
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Individual Recognition of Familiar Opponents Following Agonistic Encounters in Golden
Hamsters (Mesocricetus auratus)
Leora Ramiro, Eric Areiter, and Robert Johnston
Department of Psychology, Cornell University, Ithaca, NY
Individual recognition is an essential form of social memory for many animals. While past research has been done to
evaluate recognition of equally familiar individuals from different types of social contexts (e.g., behavioral differences in
response to a familiar conspecific from an agonistic encounter vs. a familiar conspecific from a non-aggressive encounter),
very little research exists on individual recognition of familiar individuals from a single type of social context (e.g.,
differences in response to two familiar animals encountered only within agonistic contexts). The current study addresses
this issue by investigating individual recognition within a single context that yields two different outcomes. Agonistic
encounters were used for the social interactions since fights yield two outcomes: winning and losing. In our experiment,
subjects were adult male hamsters that, over the course of 4 days, both won agonistic encounters against a male conspecific,
and were defeated by a different male. One day following the end of agonistic encounters, the subjects were tested for their
reactions to one of their previous opponents. Results demonstrate that behavioral results of the subjects were appropriate to
the stimulus male that was presented. C-fos immunocytochemistry was used to examine neural substrates of this
recognition. At the moment, IEG results implicate the dentate gyrus and basolateral amygdale. Additional regions such as
areas of the hypothalamus are currently being examined as well.
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The Child is an “Automatic Grammaticizer”
Laura Suttle, Margaret Fandrich, Shayna Muhlbauer, Marisa Brook, Rachel Bloom, and Megan Ferris
Cornell Language Acquisition Laboratory, Cornell University, Ithaca, NY
The mystery of how a child acquires their first language is especially compelling in the area of complex sentence formation
where syntax must apply recursively, materials are missing from the sentence through ellipsis, and multiple ambiguities of
meaning may be possible while at the same time many potential interpretations are not. For example, in sentences (a) and
(b), which are coordinated by the conjunction and which may involve ellipsis or missing elements in the “did too”
construction, many interpretations are possible, although many are impossible: (1)Ernie kicked his ball and Bert kicked his
ball too. (ii)Ernie kicked his ball and Bert did too. When and how does the child acquire this recursive system, and
determine the grammatical system which underlies them, when no explicit teaching is provided to the child in this area? In
this study, we introduce an experimental factorial design by which we study the child’s knowledge of sentences like 1 and
2. We use an attested elicited imitation method to assess children’s knowledge of the syntax of these kinds of sentences. 24
sentences were tested on children from 2 to 6 years of age in several developmental groups. We report results which show
that children (i) have competence for these structures at a very early age; (ii) map back and forth between sentences like (a)
and (b) and (iii) are sensitive to the grammatical factors which we manipulated in our design. We interpret our results in
terms of general theories of language acquisition, e.g., Aitchison’s “Automatic Grammaticizer” and Chomsky’s theory of
Universal Grammar.
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Selfish Punishment: Altruism can be maintained by competition among cheaters
Omar Tonsi Eldakar, Dene Leo Farrell, and David Sloan Wilson
SUNY Binghamton, Binghamton, NY
Altruistic punishment refers to a class of behaviours that deters cheating at a cost to the punisher, making it a form of
second-order altruism. Usually it is assumed that the punishers are themselves "solid citizens" who refrain from cheating.
We show in a simulation model that altruism and punishment paradoxically become negatively correlated, leading to a form
of selfish punishment. Examples of selfish punishment can be found in organisms as diverse as wasps, birds, and humans.
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Interleaved and Alternating Learning of Dependent and Independent Stimuli
Bo Pedersen and Michael Spivey
Cornell University, Ithaca, NY
In models of learning a phenomena called catastrophic interference can be observed: When learning one stimulus A and
then another stimulus B (until the error is below 5%), then A is sometimes forgotten. Traditionally this is resolved by using
interleaved learning where A and B are learned simultaneously. In this paper we present some results from backpropagation
learning that suggests that A is not forgotten, but in some sense just need a reminder to be recollected. We performed
10,000 backpropagation learning sessions with a 10x10x10 network on random A and B patterns interleaved and 10,000
with alternating A’s and B’s, where the learning of each stimulus was finished (error < 5%) before proceeding to the next
one. Surprisingly this experiment shows that the alternating learning is faster and more robust than the interleaved learning.
We interpret this result as the advantage of focusing on one stimulus at a time in a learning process, when the stimuli are
independent. But stimuli are not always independent. We therefore repeated the experiment with stimuli that were clearly
not independent by letting B be the inverse of A, and thus giving the network a multiple Xor problem to work on. This
reversed the effect. Now the interleaved learning was faster and more robust, and we interpret this as the advantage of
learning two things that are clearly related at the same time. In conclusion, interleaved and alternating learning both have
their advantages depending on the how inter-dependent the data set to be learned is.
64) U
Variations on a theme: cross cultural standards of beauty
Erica Princiotta, Kryss Cushman, and Rebecca L. Burch
Department of Psychology, SUNY Oswego, Oswego, NY
Various beauty standards and alterations to appearance that are thought to be examples of cultural differences in standards
of beauty are discussed in an evolutionary framework, highlighting how all of these seemingly different standards are
attempts to emphasize genetic quality and reproductive viability. Specifically, attempts to create supernormal stimuli and
create an illusion of symmetry are discussed.
65) U
The menstrual cycle and mood
Margaret Casper, Sara Ressing, and Rebecca L. Burch
Department of Psychology, SUNY Oswego, Oswego, NY
After a review of the literature, data are presented that show a fluctuation in mood across the menstrual cycle in both a
clinical and nonclinical sample. Fluctuations in depressive symptoms appear to fluctuate with ovulatory hormones
(estrogen in particular) and are at their nadir during ovulation. Differences between the clinical and nonclinical samples are
discussed.
66) U
The signs that she cheated
William Von Dollen and Rebecca L. Burch
Department of Psychology, SUNY Oswego, Oswego, NY
Male and female undergraduates were surveyed as to their levels of jealousy and suspicions of infidelity in their mates.
They were also asked if they had ever cheated on their partners. Males who suspected their partners of cheating did so
because of sexual factors - a lack of interest in sex or attempt to avoid them. Interestingly, these are the same behaviors that
females engage in after they cheat on their partners. Suspicions of infidelity also had effects on the males’ treatment of their
partners and willingness to have sex with them.
67) U
Seminal compounds and their possible effects on mood
Steve Kempa and Rebecca L. Burch
Department of Psychology, SUNY Oswego, Oswego, NY
The possible effects of seminal compounds on mood are reviewed, including levels of various compounds
(neurotransmitters, hormones, and their precursors), incidence of semen exposure in a college population (frequency of
unprotected vaginal, anal or oral sex in both men and women) and preliminary findings on the effect of semen exposure on
mood disorder symptoms as measured by the Beck Depression Inventory and the Beck Anxiety Inventory. Preliminary
findings suggest that women who are exposed to semen through unprotected vaginal sex report fewer depressive and
anxious symptoms, and both men and women who are exposed to seminal compounds through unprotected anal sex and
fellatio show a decrease in depressive and anxious symptoms. The compounds that are possibly responsible for this are
discussed.
68) U
Physical, Sexual, and Emotional Violence in College Couples
Rachel Olson and Rebecca L. Burch
Department of Psychology, SUNY Oswego, Oswego, NY
Seven hundred and seventy nine questionnaires (251 male, 528 female respondents) were collected at the State University
of New York at Albany. Questionnaires included questions regarding violence toward current partner, violence from
current partner, arguments, jealousy and jealousy evocation. Males reported more violence toward their partners than
females. Males also reported more violence from their partners than females. Gender differences were also found in types
of violence (sexual, physical, emotional), the relationship between jealousy and violence, and frequency of jealousy
evocation. It appears that sexual jealousy in the college sample was a major factor in the triggering of violence.
69) U
The role of parental support in dating preferences
Natasha Mapes and Rebecca L. Burch
Department of Psychology, SUNY Oswego, Oswego, NY
In a sample of over 500 male and female undergraduates at SUNY Oswego, questions were asked regarding the
participants’ families of origin, abandonment, and levels of perceived parental support, along with checklists of preferences
for marriage and dating partners. Individuals who were abandoned, especially women, had lower expectations for marriage
partners and dating partners. In addition, level of perceived parental support (particularly that of the opposite sex parent)
correlated with higher expectations for marriage and dating partners.
70) U
Phonons in Yukawa lattices
Patrick J. O'Brien and Stamatios Kyrkos
Le Moyne College, Syracuse, NY 13214
Yukawa systems are good representations of structures forming in dusty plasma and colloidal experiments. The theoretical
work that has been done involves the understanding of the theoretical structure of phonon dispersion in Yukawa lattices.
After calculating the phonon spectrum for 2D hexagonal Yukawa lattices, we have aimed to numerically calculate the
phonon spectrum for a 3D Yukawa lattice.
71) U
Evaluating the impact of the xylem wound response on the measure of hydraulic resistance in
plants
Amy Fisher and Peter Melcher
Biology Department, Ithaca College, Ithaca, NY
Measuring xylem hydraulic resistance is an important character that is used to describe plant adaptations to water
availability. The measure of hydraulic resistance in plants has been well characterized for the last 40 years (with early
experiments that date back 250 years ago). Because the measure of hydraulic resistance relies on data collected on excised
plant material, understanding the impact that a wound-response has on the measurement of hydraulic resistance is of great
importance and this has been overlooked in the literature. We found that the xylem wound response rapidly increases the
true estimates of xylem hydraulic resistance by up to 80% in some species. We investigated various chemical and
mechanical procedures to remove the xylem-wound response and found that recutting of the stem ends after 30-mins of
perfusing 20 mM KCl though the xylem resulted in non-wounded values that could be used to estimate the true xylem
hydraulic resistance in Acer rubrum (red maple) stems. We also found that various chemical treatments could reduce the
wound response in maple stems. We are currently investigating methods to remove a muscilage induced wound response in
Hibiscus rosa petioles. These new data are will allow for proper characterization of plant hydraulic form (hydraulic
architecture). These data will also provide new insight on the basic mechanisms used by plants to move water through their
highly branched vascular networks. This is pertinent to understand the full influence that plant hydraulic form has on plant
drought adaptations.
72) G
Environmental influence on immediate mating versus bet-hedging mating tactic choice in first
summer generation Aquarius
Mike Dlugos and R. Stimson Wilcox
SUNY Binghamton, Binghamton, NY
Behavioral flexibility allows adaptation to rapidly changing environmental conditions, often when genetic evolution cannot.
The water strider Aquarius remigis has evolved flexibility in the timing of its reproductive behavior in response to seasonal
time constraints. In areas where season length is long, striders mate during the summer they hatch (immediate mating
tactic), as opposed to deferring mating until after the completion of winter diapause (bet-hedging mating tactic). The aim of
this study is to determine the environmental factors influencing A. remigis mating tactic choice, which was studied using a
2x2x2 indoor treatment study using all possible combinations of a normal/ extended seasonal photoperiod, low/ high food
regime, and fish predators present/ absent. The data suggests a greater proportion of striders become immediate maters over
bet-hedgers under artificially extended seasonal photoperiod, high food, and predator absent treatments. This was supported
by environmental monitoring indicating that streams supporting immediate mating striders (Vly Creek, Voorheesville, NY)
have higher food abundance, as well as higher temperatures, than streams supporting only bet-hedgers.
73) U
Improving the Temporal and Spatial Resolution of Tethered Particle Motion Measurements
Using 40nm Fluorescent Beads
Shreyans Shah
McGill University, Montreal, Quebec Canada
The possibilities of improving upon previous research concerning single-particle tracking using the Tethered Particle
Motion (TPM) method will be discussed. This method involves tracking the motion of a colloidal microsphere tethered by a
DNA molecule to a glass surface. As a result of Brownian motion, the tethered microspherical particle attached to the DNA
strand will tether about the immobilized section of DNA. Previous research for 200 nm tether beads has shown that the
average standard deviation of this motion exhibits a possible linear relationship with DNA length. The calibration curves
generated using this research; however, show a precision in the particle motion standard deviation measurements that it is
hoped can be improved. In contrast, 40 nm beads are too small to be imaged using the standard differential interference
contrast microscopy. Our research has shown that these smaller beads can, however, be imaged using fluorescence
microscopy. We have also shown that 40 nm fluorescent bead Brownian motion measurements are consistent with 200 nm
beads. The potential application of these smaller beads in the improving the time resolution of TPM measurements will be
addressed.
74) G
Molecular Epidemiology of Streptococcus pneumoniae Serotype 19A
Wei-Chung Chen
Yale University, New Haven, CT
Streptococcous pneumoniae is a major cause of infections in pediatric populations and it is the goal of this project to further
explore areas that will improve on future vaccine and treatment developments. There appears to be a rise in serotype 19A
with the increase usage of 7-valent pneumococcal conjugate vaccine (PCV7) to curtail the effect of S. pneumoniae
infection. We identified tissue-specific virulence factors associated with S. pneumoniae 19A strains that cause clinical
diseases such as pneumonia and meningitis in children under the age of five, and compared the distribution of the identified
virulence factors among a large collection of pneumococcal strains from the pre-vaccine and post-vaccine era. 30
subtraction PCR (sPCR) fragments were screened using dot-blot hybridization. Among the probes screened, probe 19(A8)
was found to play a potential role in the pathogenesis of pneumonia after PCV-7 vaccination. The probe was found to
appear 0.58 (95% CI, 0.41-0.80) times less frequently among the pre-vaccination blood isolates than carriage isolates.
However, the probe appeared 1.57 (95% CI, 1.11-2.21) times more frequently among post-vaccination blood isolates than
carriage isolates. Another probe that could play a potential role in the pathogenesis of pneumonia after vaccination is probe
14(G11). The prevalence ratio increased from 1.6 (95% CI, 1.07-2.40) times to 2.5 (95% CI, 1.60-3.80) times more
frequently among post-vaccination blood isolates than carriage isolates. Through different experiments, two genes of
potential importance in the pathogenesis of pneumonia were located, and two genes of potential importance in bacterial
colonization were also identified.
75) G
Peptide libraries containing Phe analogs as reversible inhibitors for thrombin
Cristina Clement, Janet Gonzalez, Juan Barquero and Manfred Philipp.
Chemistry Department, Lehman College, City University of New York, Bronx, New York City, NY.
We are reporting the manual synthesis of three new tetrapeptide libraries containing phenylalanine (Phe) analogs like
trans/(cis) cinnamic, dihydrocinnamic acids, D-Naphthylalanine (DNal) and the Phe constrained analog 1,2,3,4- (D)tetrahydroisoquinoline-3-carboxylic acid (D) Tic in the P3 position in the sequence space DPhe (P3)–Pro (P2)–DArg (P1)P1’ which was shown previously to inhibit thrombin in vitro. The libraries were synthesized using the partition and mixing
procedure. Ten variation in the P1’ position were performed using natural and un-natural amino-acids that were shown very
good inhibitory activity for thrombin in the sequence space DPhe (P3)–Pro (P2)–DArg-P1’, i.e. P1’ = D-Ser, D-Cys, D-Ala,
L-Thi, D-Tic, D-His, D-Pro, D-Thr, D-Asn and D-Gln for each variation with trans-cinnamic, dyhidrocinnamic acids, DTic
or DNal in P3 position. Preliminary results showed that replacement of DPhe in P3 position with DNal had a two fold
increased inhibitory activity for thrombin in an in vitro assay competing with the chromogenic substrate S2238. The transisomers of the tetrapeptides were at least five fold more active than the cis-isomers while the release of double bond
constrain through dihydrocinnamic acid had at least two fold better activity than the cis-isomers but less activity than the
trans-isomers. Our molecular modeling studies support the hypothesis that tetrapeptides differing in one single amino acid
at P1’ position are adopting different conformations into active site of thrombin which might be related to significant
experimentally determined differences in their inhibitory potential.