Emily Alper and Ellie Haeg - CATEGORY
the number one food-borne pathogen in the United States, which has been
demonstrated in recent Salmonella
outbreaks. Previously, dangerous serovars of Salmonella have been eliminated by eradication of the entire
serovar. This is problematic because an empty ecological niche can be filled
with a more virulent serovar. Recently, S.
Kentucky filled an empty niche and has become one of the most prominent
serovars in processed chicken breasts and potentially poses a serious human
health risk. The goals of our project were to see if eighteen pre-identified
genes specific to only one strain of S.
Kentucky were specific to all strains of S.
Kentucky, and to see if these genes were present in five other common serovars:
S. Enteritidis, S. Typhimurium, S.
Worhtington, S. Schwarzengrund. To do
this we used multiplex PCR and gel electrophoresis. Results showed that the
genes were completely present in all strains of S. Kentucky and mostly absent in other serovars. The one exception
we had was eleven of the genes were 100% present in S. Worthington. This indicates that if Salmonella continues to be eliminated through traditional ways of
complete eradication S. Worthington
is in position to fill the ecological niche of S. Kentucky.
Hybrid vehicles have gained a great deal of attention in past years because they use conventional methods of propulsion coupled with electric power to reduce fuel consumption and emissions. I engineered an inexpensive fuel-displacement device that saved the hydraulic-hybrid vehicle team at the University of Minnesota thousands of dollars because they did not have to purchase a fuel-flow meter to measure fuel consumption. My device measured fuel consumption of a 1.13-L Perkins diesel engine used in a hydraulic-hybrid Polaris Ranger utility vehicle. My fuel-displacement device provided benefits over commercially available flow meters by allowing the engine to warm up to operating temperature while using fuel from the fuel tank prior to testing and then switching fuel flow to an incremented container during testing. After testing fuel consumption using my device, I used a Willans line method in MatLab to develop engine maps by extrapolating fuel consumption and efficiency of test data, using a least squares fit. Then, I compared maps of test data to data in a second set of engine maps that I developed using five consumption points measured by the engine manufacturer (Perkins Engine Company) at wide open throttle and while the engine was being used as a generator. By comparing efficiency maps, I determined that the most efficient operating range of the 1.13-L Perkins diesel engine in the hybrid vehicle is between 2200 and 2600 RPM and at torque outputs between 50 and 60 Nm. Using my findings, vehicle controls for the powertrain in the hydraulic-hybrid Polaris Ranger will be modified to run the engine within the range of peak efficiency at all times.
Samarth Damania - CATEGORY
My study was an
extension of the HaloFit Project, which studies aspects of player
and team performance in professional Halo 3, a first-person shooter video game. I used the database of the HaloFit Project to
mine relevant player and team statistics from the 2008 and 2009 seasons for
professional Halo 3 to determine impact of change in team composition on player
and team performance, and to use past performance to predict future success of
players and teams. I used PivotTables in Excel to sort player classifications
(professional and amateur), player change (how often a player moves to a new
team), team change (how often new players join a team), and performance
measures of teams and players (kill/death ratio and assist ratio for individual
performance and win ratio for team performance). I then used
MySQL to aggregate data into PivotTables and used Waikato Environment for Knowledge Analysis to
execute prediction of performance. Results showed that while individual success is not as greatly affected by
switching teams, team performance is significantly affected. While I was unable
to predict future performance from the dataset, the innovation of my research
lies in that it is a data-driven approach to investigating a social science
The goal of my study was to synthesize 2-methoxy-9,10-bis(4-methoxyphenyl)indenotetracene, a novel indene derivative, for implementation in organic photovoltaic devices. I began by synthesizing a starting material (5,6,11,12-tetrachlorotetracene) using a procedure outlined by Yagodkin et al. (2009). Next, I synthesized the Grignard reagent (4-methoxyphenyl)magnesium bromide. I combined those two compounds with a PEPPSI-iPr catalyst in a Kumada cross-coupling reaction to produce the methoxylated indene derivative. To purify the derivative, I used two techniques: wet column chromatography and recrystalization. To optimize the purification procedure for wet column chromatography, I tested various ratios of hexanes to methylene chloride, finding that a 2:1 ratio (v/v) was the most effective solvent system. When thin-layer chromatography tests showed impurities after wet column purification, I tested various solvent systems, finding that a 2:2:1 ratio (v/v) of toluene, isopropanol, and methanol eliminated impurities. 1H NMR showed that purification of the methoxylated indene derivative was highly successful; therefore, I concentrated on scaling-up the reaction, which allowed the targeted indene derivative to be synthesized in quantities large enough for implementation in an organic photovoltaic device.
The goal of my project was to find a surface coating that would prevent
microalgae build-up on walls and tubing of photobioreactors that are used to
grow microalgae for biofuel production. I applied the following non-stick
products that are currently on the market to a pilot plexiglass photobioreactor:
TDL Dry Lube, Silicone Lube, NanoSafeguard Sealant, and Easy On Bottom Coating.
I found that Easy On Bottom Coating and TDL Dry Lube worked best, significantly
reducing microalgae buildup on the pilot photobioreactor (p < 0.05). Easy On
Bottom Coating worked almost as well as TDL Dry Lube when the plexiglass had
been roughed with sandpaper before being coated (p = 0.001). Furthermore, my results suggest
that agitation significantly reduces microalgae build-up on photobioreactors (p
< 0.05). While my study did identify an important problem in biofuel
production using microalgae, results did not suggest a commercially viable
method of reducing microalgae build-up on photobioreactor.
Matthew Hackner - CATEGORY
Matthew worked in the Chemistry Engineering Department at the University of Minnesota under the supervision of Dr. David Blank. Matthew researched the interaction of a new type of plastic called regiorandom P3HT with regioregular P3HT, which is already used in solar cells. Regioregular is currently used in solar cells because it absorbs
light and outputs usable energy well. Regiorandom
also absorbs light but does not output usable
energy because it fluoresces. Using absorption
spectroscopy and fluorimetry, Matthew found that regioregular almost completely quenches
fluorescence of regiorandom. His results suggest
that adding regioregular to regiorandom could
harness the fluorescent energy of regiorandom
to increase electrical output organic solar cells.
Cara Kowalchyk Rebecca Southern - CATEGORY
Cara and Rebecca collaborated on a project,
working in the Microbiology Department at the University of St.
of Dr. Jayna
Ditty. The goal
of Cara and
was to determine if the bacteria P. putida Fu1 can be used in
bioremediation of furan compounds that are toxic,
possibly carcinogenic agricultural byproducts.
They used capillary assays to measure responses
of mutant strains of P. putida Fu1 to furan com-
pounds, showing that P. putida Fu1 does sense
these compounds. They also used agarose plug
assays to determine if mutant strains of P. putida
Fu1 (P. putida PSF2 and P. putida PSF9) respond
to 2-furoic acid. Their results suggested that the
gene (psfb) in P. putida PSF2 may be involved in
regulating chemotaxis to 2-furoic acid, but results
did not support that the gene in P. putida PSF9 is
involved in repressing the trigger for chemotactic
response of P. putida Fu1.
Caleb worked at Access Genetics under the supervision of Dr. Ron McGlennen and Stephen Trusheim (class of 2009). Caleb designed a neural
network using Java programming that selectively
identifies cancerous human bladder cells. The neual network analyzes morphometric characteristics
of bladder cells in a way that simulated the process
that a pathologist follows to examine cell characteristics in order to detect abnormalities. The program
that Caleb designed will enable diagnoses to be
done more specifically, more quickly, and at a lower
cost than diagnoses done by pathologists, so treatments can commence earlier.
Michael worked at Medtronic, Inc., under the supervision of Dr. Tim Laske. Michael
determined how the heart is affected by impacts to the chest,
specifically during athletic participation. He used a
combination of a crash-test dummy and a chest
model he engineered to measure the forces that
are placed on the chest and heart during athletic
impacts. His results showed that a heart can experience up to 20 pounds of force during athletic impacts. Engineers will use Michael’s results to
develop heart valves and stents that can withstand
forces athletes experience during practices and
Roshny Vijayakar and Aris Prince - CATEGORY
Roshny and Aris collaborated on a project, working
in the Department of Horticultural Science at the
University of Minnesota under
of Dr. Gary
and Aris grew
from locations with different altitudes and latitudes around the
world. They then exposed the Arabidopsis
seedlings to UV-B radiation. Results showed that
plant sensitivity to UV-B did not depend on alti-
tude or latitude of the sites where the seeds were
collected; however, they found a surprising result
that suggests plants from Japan have developed
decreased sensitivity to UV-B nuclear radiation.
The next step is to determine if plants from other
sites that have been exposed to nuclear radiation
also show altered UV-B sensitivity.
Addison Weiler - CATEGORY
in the Chemical Engi-
neering and Materials
at the University of
Minnesota under the
supervision of Dr. Russell Holmes. Addison engineered a new type
of organic solar cell using organic materials that
absorb infrared radiation in order to more effi-
ciently convert radiation from the sun to usable
electrical energy. He tested different concentra-
tions of the organic materials in varying architec-
tures, finding that laying copper phthalocyanine in a planar architecture with lead phthalocyanine
and carbon fullerene 60 gives a power conversion
efficiency of 1.53%. This is the highest efficiency
ever achieved for organic solar cells that use similar
chemicals and architectures.