Phthaloylphosphide has unusually low basicity at the phosphorus atom due to
the electron-withdrawing nature of the carbonyl groups, yet reacts readily,
by nucleophilic substitution, with primary and secondary alkyl halides. We have
produced, in high yield, the first reported examples of fluorous ponytail alkylphthaloylphosphines.
The first product contains a two-carbon spacer and a six-carbon ponytail and
the second also had a two-carbon spacer and a ten-carbon ponytail. The yields
were 79.1% and 87.5% respectively. The high yields are significant in terms
of lowering the cost on production of ponytail-substituted phosphorus precursors.
Details of characterization will be presented.
Volatile chemicals, called taggants, are required to be added to commercial explosives for the purpose of detection by dogs. 2,3-dimethyl-2,3-dinitrobutane(DMNB) was studied using a PDMS/DVB SPME fiber and GC-MS was used to analyze. The partition coefficients of DMNB were determined for the PDMS/DVB fiber. The coefficient between the headspace and the solid was 2.9x10-9. It was also discovered that the coefficient measured for the interface between the fiber and the air was greater than 1 (1.55 actually).
Model System for Examining Radial Distribution Functions
Cory Christenson and Kelly Younge (advisor: Paul Saulnier)
Radial distribution functions provide an analytical means of examining an amorphous material. These functions have a wide range of applicability as they provide a method to investigate the spatial distribution of a collection of particles that possess only short-range order. Additionally, they may be used to infer the particle-particle interaction potentials present in an aggregation of particles. The radial distribution function was calculated for two-dimensional systems of hard spheres consisting of different area fractions.
Concurrent paper session 1b: Nobel Hall, Room 222, 2:15 - 3:15 p.m.
James Welsh, Chair
Peripheral Auditory Processing Model of Frog
Amit Bohara (Advisor: Jan Wotton) 2:15 p.m.
The auditory nervous system processing in frog is modeled upto the first layer of neuronal encoding. Band pass filters are used to model the peripheral processing in the ear; and an RC circuit integrate and fire method is used to model the temporal encoding undergone by sound signals in the first layer of neurons. The adaptive patterns in neurons are discussed and further plans to construct neuronal networks will be discussed.
Electrophysiological Characterization of Single Cell Response Patterns in the Auditory Midbrain of the Leopard Frog (Rana pipiens)
Kimberly McArthur (advisor: Michael Ferragamo) 2:30 p.m.
Frogs primarily use acoustic signals to facilitate reproduction. A male produces
a call indicative of his species and relative attractiveness in order to attract
a prospective female mate and to maintain his position in the social hierarchy.
Signal cues such as frequency, envelope, and duration must therefore be processed
by the frog central auditory system. Since the midbrain acts as a convergence
point for afferent auditory signals, individual cells in the midbrain can encode
and integrate information about signal cues using a variety of neural response
patterns. In this study, we describe several categories of these response patterns
and how they might encode neuroethologically relevant characteristics of an
Coping with Shyness: Physiological, Genetic, and Social Contributions to Personality Traits
Lisa Swenson, Jake Hansen, & Alyssa De Haan (advisor: Timothy Robinson) 2:45 p.m.
Abstract to be posted.
Tropical Storms of Southeastern Minnesota: Analysis of Late Cambrian Flat-pebble Conglomerates in the St. Lawrence Formation
Nathan Suurmeyer (advisor: Russell Shapiro)
The St. Lawrence Formation of the Late Cambrian crops out the Minnesota River Valley in southeastern Minnesota and contains flat-pebble conglomerates (FPC’s), which are composed of disc-shaped pebbles that are intraclastic in nature. Field and laboratory analysis of these FPC’s show that they were created by storm events that ripped up resistant layers in a shallow marine environment below storm wave base.
Poster Session Nobel Hall
Lobby 3:15-3:45 p.m.
Phonetic Interpretation and Influence of Sentence
Aaltje Baumgart (Advisor: Jan Wotton)
This study examined the interpretation of ambiguous vowels in a target word within a sentence. The vowel was altered to change the meaning of the target word, for example, "cat" to "cot." Subjects reported hearing the target words the most clearly. Subjects also indicated they heard a different vowel when listening to the non-contextual vowel, usually instead reporting the vowel that was contextual. Subjects changed sentences to be semantically congruent by altering the sentence.
Paleoautecology of Renalcis, a Calcified Microbe from
Cambrian Reef Complexes: a Quantitative Approach
Ali Cordie (Advisor: Russell Shapiro)
Renalcis is a group of microfossils found in abundance in the Cambrian. Renalcis has been defined as clusters of micrite chambers connected in a shrub-like pattern. However, biological identity remains in question. Data were analyzed to interpret the growth direction, patterns, and trends. Four main growth patterns identified (pendent, branching upward, clustered, dense). Renalcis appears to grow independent of other reef metazoans. Further petrologic research is needed in order to more accurately qualify the computer analyses.
Mercury in Voyageurs National Park Aquatic Food Webs
Bjorn Gangeness (Advisor: Jeffrey Jeremiason)
This study is part of a collaborative investigation (Gustavus Adolphus College, USGS, University of Wisconsin-La Crosse, and the state of Minnesota) initiated to identify ecosystem processes or factors leading to high yet variable fish mercury concentrations in Voyageurs National Park. This poster focuses on how food web characteristics impact northern pike (Esox lucius) mercury levels in Voyageurs National Park. Northern pike from Ryan Lake and Tooth Lake in the Park contain some of the highest mercury concentrations reported in Minnesota, resulting in fish consumption advice of “do not eat” in these two lakes. We sampled and analyzed northern pike and age-1 yellow perch (Perca flavescens) from thirteen interior Park lakes for total mercury and stable isotopes of nitrogen and carbon between 2000 and 2002. Stable isotopes have also been measured in crayfish (6 lakes) and dragonfly larvae (xx lakes). Comparing mercury levels in yellow perch collected in 2000 to historical northern pike concentrations indicated that northern pike:perch ratios in Ryan and Tooth Lakes were elevated relative to other Park lakes. However, the more recent pike mercury levels (2001-2002) are highly correlated with yellow perch mercury concentrations. In addition, pike:perch ratios in Ryan and Tooth lake are similar to other lakes in the Park based on the more recent data. Stable isotopes of nitrogen support these conclusions indicating that food web differences are not responsible for high mercury levels found in Tooth and Ryan lakes.
Resonance Raman and Computational Study of Resveratrol and Related Stilbene Derivatives
Justin Scanlan (Advisor: Jonathan Smith)
Resveratrol (3,5,4’-trihydroxy-trans-stilbene), derived from grapes, has been identified as an antioxidant that appears to play a role in reducing the affects of aging and has anticancer properties. We investigate the solution geometry and dynamics of resveratrol and related stilbene derivatives with varying degrees of biological activity using ab initio calculations (Gaussian 03) coupled to resonance Raman spectroscopy.
Measurement of Contaminated Groundwater Discharge
to Surface Water at Seven Mile Creek, Nicollet County, Minnesota
Samuel M. Johnson (Advisors: James Welsh and Russell Shapiro)
Data taken from nine sampling sites at Seven Mile Creek, Nicollet County, Minnesota, show that groundwater often has high concentrations of nitrate and chloride. This study focuses on the contamination of the surface water as a result of discharging groundwater. The groundwater is contaminated mainly from agricultural fields to the north of the stream and flows through New Ulm till and Jordan sandstone before reaching surface water.
Moving Toward an Investigative Laboratory Curriculum -- Affinity Purification of Recombinant Fumarase
Emily King (Advisor: Jeffrey Dahlseid)
Science laboratory curricula are enriched when there are opportunities for personal connection through extended project continuity, project ownership, and creative investigation. To so enrich students' biochemistry laboratory experience, we have begun development of a curriculum with a primary focus upon purification and characterization of a protein enzyme from baker's yeast. Using baker's yeast as a model organism also allows reinforcement of students' molecular genetic literacy. A yeast strain expressing carboxy-terminal, histidine-tagged recombinant fumarase from a high-copy plasmid was used as a rich source of enzyme. In addition, media containing lactate, a non-fermentable carbon source, was used to promote high levels of fumarase expression and growth conditions were determined for optimal yield of wet cell mass. Cell lysis and extract storage conditions suitable for an undergraduate curriculum were determined. The separation of fumarase from total cellular protein was evaluated using three different metals (Ni2+, Co2+, and Cu2+) in immobilized-metal affinity chromatography. Together, these procedures result in an effective, one-step protocol for isolating and purifying histidine-tagged fumarase with Ni2+-affinity chromatography. This segment of the curriculum establishes continuity over several laboratory periods while emphasizing student responsibility and will lead to opportunities for student directed investigation.
Session 2: 3:45-5:15pm
Concurrent paper session 2a: Nobel Hall, Room 222, 3:45-5:15 p.m.
Steven Mellema, Chair
Worthwhile Wind? The Feasibility of Wind Power at Gustavus
Jared Lee and Carl Ferkinhoff (Advisor: Charles Niederriter) 3:45 p.m.
Few would argue that the Gustavus campus is a windy place. With this in mind,
a feasibility study was begun three years ago to see if the wind could provide
a cheap and clean source of power for Gustavus. In the last few months, recent
data have indicated it would indeed be feasible. Wind shear data, tower correlations,
and estimated power production all point to wind power being a viable source
for Gustavus' energy needs.
Acoustical Interferometry and Imaging
Andrew Konicek (Advisor: Charles Niederriter) 4:00
The frequency spectra and visibility curves were taken for transducers to verify the Fourier relation between the two curves. Transducer pairs were set up to create two arms of an acoustic interferometer. The relationship to be verified was that the product of the half-widths of the two curves is the speed of sound divided by 2*pi. The resulting data showed that for all measurements the data significantly disagreed, but was on the correct order of magnitude.
Organ Pipe Reeds and Acoustics
John Purdham and Dave Fowler (Advisor: Thomas Huber) 4:15
The way organ reeds vibrated used to be modeled as a simple vibration about a fixed line. Our research has revealed that more complicated modes exist, and is focused on recording and analyzing them. Capturing the vibrations is done by either using an optical interferometer, or by using a strobe light near the frequency of oscillation and a video camera. This data is digitally transferred to a computer where it can be analyzed by programs.
Time Resolved Photon Correlation Spectroscopy
Scott Ernst and Nate Johnson (advisor: Paul Saulnier ) 4:30 p.m.
Time-Resolved Photon Correlation Spectroscopy (TRPCS) will be discussed. TRPCS
is a technique that uses a pulsed laser system along with an electronic temporal
gate to expand the limits of sample concentration that conventional Photon Correlation
Spectroscopy (PCS) can successfully probe. In a TRPCS experiment, a laser pulse
is incident on a sample and a specific portion of the output pulse is examined
while all other (multiply scattered) light is rejected.
Analysis of Herbicides in the Minnesota River by SPME-assisted
Joseph Katzenmeyer (Advisor: Lawrence Potts) 4:45 p.m.
Solid-phase microextraction (SPME) can be used to greatly increase the sensitivity
of a method. It also eliminates many of the steps needed to do a traditional
extraction with organic solvents. This, in turn, eliminates organic solvent
waste. In this situation a polyacrylate fiber was used to extract the organics
from a sample of Minnesota River water. Various herbicides could be seen, including:
atrazine, cyanazine, alachlor and metolachlor. With a preconcentration step
using solid-phase extraction, the method allowed the detection of atrazine down
to approximately 10 ppt.
Visualization of Relativistic Objects
Scott Ernst (Advisor: ) 5:00 p.m.
When introducing students to Special Relativity, the standard example of a
contracted meter stick is misleadingly used to describe how the appearance of
an object changes at relativistic speeds. This talk focuses on various transformations
incorporating effects such as aberration of light and Lorentz contraction. Using
a computer program I created simulating relativistic motion, I will illustrate
several interesting results concerning the appearance of complicated objects
traveling at relativistic speeds and differences between the transformations.
Concurrent paper session 2b: Nobel Hall, Room 201, 3:45-5:15 p.m.
Colleen Jacks, Chair
Primary Attachment and Metastasis 24-48 Hours Post Injection Using EGFP in B16 Melanoma
Matthew D. Schwartz and David Heldman (Advisor William Heidcamp) 3:45 p.m.
Previous studies have shown it is possible to tag B16 mouse melanoma cells with vital stains to study the attachment, growth and metastasis of tumors. These studies used fluorescent cytoplasmic or membrane bound tags and were useful for only the first few hours post injection before, with cell division, the signal became too dim to detect. Other studies on metastasis use colony formation after one to two weeks, too late for detection of the primary attachment of melanoma cells to the endothelial lining of lungs. A transfected GFP B16 cell line was created in our labs. Preliminary testing of the transfected cell line allowed FACS sorting, but the intensity of the fluorescence was too low for epifluorescence. Subsequent retransfection with EGFP produced a clone with enough intensity for use with epifluorescence. This newly created metastatic clone is used to study primary attachment of B16 tumor cells in vivo 24-48 hours after tail vein injection a time during which the components of the extracellular matrix (ECM) are most important.
Effects of Nitrate Additions on Melilotus officinalis
James Eckberg & Elizabeth Bockman (Advisor: Pamela Kittelson)
Melilotus officinalis is invasive to tallgrass prairie restorations in southern Minnesota. Typical M. officinalis eradication techniques (i.e. fire, mowing and herbicide) indiscriminately remove prairie plants and may decrease native community diversity. In this experiment we tested the effect of nitrate additions on M. officinalis establishment. First-year data indicate an 80% minimum decrease in M. officinalis abundance (Kruskal-Wallis H= 67.0 dF =3, p<0.05). These initial results suggest that even low concentrations of nitrogen may dramatically reduce M. officinalis dominance. Results from our study could aid in developing effective eradication techniques for M. officinalis from tallgrass prairies.
Does Phenytoin Affect iNOS Directly?
Eric Boyum (Advisor: John Lammert) 4:15 p.m.
Phenytoin (PHT), an anticonvulsant medicine, has been found to have anti-inflammatory effects in patients with rheumatoid arthritis. Previous work in our lab found that PHT inhibits the production of nitric oxide (NO), a known inflammatory mediator, by directly or indirectly affecting an enzyme that manufactures it, inducible nitric oxide synthase (iNOS). Our research inquires as to whether PHT affects iNOS directly or indirectly in mouse macrophage-like cells. Murine iNOS has been isolated for this ongoing research project.
Examination of Methods in the Release of Physical Dormancy in a Prairie Legume
Emily Helliwell (Advisor: Pamela Kittelson) 4:30 p.m.
Seed dormancy is considered to be adaptive in the sense that germination can
be postponed to ensure optimal conditions for the survival of seedlings. The
purpose of this project is to find the method of scarification that ensures
highest seed germination in physically dormant seeds of lead plant (Amorpha
canescens). The effectiveness of each treatment was determined through comparing
the percent germination and amount of time elapsed until germination.
The Intramolecular Diels-Alder Reactions of Silyloxyfurans
Philip Williams (Advisor: Scott Bur) 4:45 p.m.
Many interesting molecules found in nature possess biological activity including anti-HIV, anti-microbial, anti-fungal, and anti-cancer activity. Although the biological activity of these naturally occurring products is wide-ranging, these molecules share a common structural framework. The differences are in the way the molecules are decorated. We are examining the use of an intramolecular Diels-Alder reaction that could easily make the core structure in a way that is easy to decorate and be used for making a variety of biologically interesting natural products.
Stress and Performance: A Longitudinal Study of the Swim Season
AnnMarie Miller (Advisor: Timothy Robinson) 5:00 p.m.
Abstract to be posted.