November 4, 2002
Changes in Social Behavior in the Mantled Howler Monkey (Alouatta palliata) due to Infant Presence
Mentor: Dr. Robert Eckstein
Abstract: During part of the creation
of a new method of phthalate monoester extraction in breast milk, Acrodisc
filters were added and the phthalate monoesters disappeared. Phthalates
can produce altered sertoli cell function, hypospadius, fetal death, and
birth defects in rats as well as altered semen quality in humans.
This investigation compares the phthalate monoester extraction in Acrodisc
filters to the extraction in Nexus columns, and compares the extraction
at three pH levels. A standard solution (100 ppm monobutyl phthalate
(MBP) and 100 ppm ethylhexyl phthalate (MEHP)) at three pH levels was pushed
through a 10 ml syringe and an Acrodisc syringe tip filter at 2 ml intervals
until 8 mls were filtered. Likewise, the solutions were pulled through
a Nexus column after a wash of ethyl acetate, acetonitrile, and solution
at a similar pH. All samples were then analyzed using HPLC MS/MS
at Lund University in Sweden. There was not a significant difference
(p > 0.05) in the percent recovery of phthalate monoesters in Acrodisc
extraction in comparison to the original unfiltered solution. In
contrast, the recovery of extracted phthalate monoesters was significantly
different (p = 0.05) than the unfiltered solution in Nexus columns.
As a result of this study, Acrodisc filters are not the problem with the
missing monoesters, and these filters can be used as filters without extracting
phthalate monoesters. The findings also complete the development
of a new method of phthalate monoester extraction in breast milk, which
may help identify sources of phthalate exposure in infants.
Doug Lane
September 16, 2002
A Study of the Bluebird Boxes at Warren Wilson College
Mentor: Dr. Lou Weber
Abstract: The eastern bluebird
(Sialia sialis) has been in a major population decline for the first
75 years of the twentieth century. Much of this loss has been due
to human changes that reduce the amount of cavities available for bluebirds
to breed in and competition from introduced species. In the late
1970’s humans started to help the bluebird in finding new cavities
by erecting nest boxes along bluebird trails. The Biology and Environmental
Studies departments at Warren Wilson College have been trying to help for
several years. Unfortunately before this study we were unaware of
where all of our nest boxes were located, if they were being used and by
what species, and if any pattern exists in their use that could provide
information to improve future efforts. My objective was to answer
these unknowns and provide any additional information that may be useful
to our aid of the eastern bluebird. I mapped and monitored each box
to find what species if any was using them, measured any quantifiable aspect
of placement, and compared the data to find a pattern if one existed.
I found and mapped 18 bluebird boxes with a total of 11 bluebird nests,
5 of which had active bluebirds in them. Three of these boxes had
other species in them. There was no pattern found in my quantifiable
data. WWC is doing well in our aid to the eastern bluebird.
Our population is growing as shown by 10 parents producing 15 chicks that
fledged. Installation of predator guards is highly recommended along
fencerows. There are currently plans to expand the amount of nest
boxes that we have available and further help the bluebirds that come use
the campus by installing predator guards.
Naomi Ndavu
October 7, 2002
Impact of Warren Wilson Farm on Water Quality of Two Campus Streams
before Restoration
Mentor: Dr. Mark Brenner
Abstract: Grazing of animals in pastures close to watersheds
and runoff from agricultural fields and feedlots are a major source of
non-point water pollution. Warren Wilson College is committed to reducing
these types of inputs and restoring local streams.
This study compared water quality within two streams to obtain data
prior to the restoration. Concentration of ammonia (NH3) and phosphate
(PO4), total suspended solids (TSS) and biological oxygen demand (BOD)
were measured as indicators of water quality. Three sub-samples were
collected from each upstream and downstream site. Four samples were collected
in the spring of 2002 and four in the summer of 2002.
The results were analyzed using a paired
t-test. A comparison of the amount of TSS upstream and downstream did not
have a significant difference in either stream; the p-value for the Swim
Pond Stream was 0.4374 while that for Berea Stream was 0.3421. The concentration
of BOD showed no significant difference within the two streams; the p-value
for the Swim Pond Stream was 0.4422, while that for Berea Stream was 0.2054.
Comparison of NH3 upstream and downstream was significant in the Swim Pond
Stream with a p-value of 0.0393; this was probably due to the animals that
live in the pond and nitrification by bacteria. There was no significant
difference in Berea Stream, with a p-value of 0.2443. The comparison of
PO4 was extremely significant in Berea Stream with a p-value of 0.0007.
This could be due to the rocks that form the riverbed, and due to runoff
from the adjacent pasture. The Swim Pond Stream had a p-value of 0.4024,
which was not significant. It should be noted that these samples were collected
during a drought period and hence the data obtained does not provide an
accurate idea as to what is happening within the streams.
Choong Teow
October 7, 2002
Analysis of the ingredients of Dong Quai, Angelica Sinensis.
Mentor: Dr. Dean Kahl
Abstract: Dong Quai is a popular oriental
herb that is widely used to treat illnesses. It is also commonly used as
food flavoring. Thirty-five components have been isolated from Dong Quai.
Two of the major components are Z-ligustilide and gamma-terpinene. The
purpose of this research was to determine the composition of Dong Quai
root oil and also to compare Dong Quai root oil made from Chinese and Malaysian
roots. The analysis involved a standard root pill, Dong Quai root from
China, and Dong Quai root from Malaysia. The essential oils of Dong Quai
roots were isolated by steam distillation. The distillate was collected,
and the essential oil was extracted with diethyl ether. The essential oil
was analyzed by gas chromatography/mass spectrometry. The two major peaks
in the total ion chromatogram (TIC) were due to Z-ligustilide and gamma-terpinene.
The mass spectra were characteristic for each compound. The mass spectra
for the root pill, root from China, and root from Malaysia were similar
to the mass spectra obtained from research carried out in China by Y. Chen’s
research group. The TIC showed that the ratios of gamma-terpinene to Z-ligustilide
in the essential oils were reasonably close for the three samples. Since
this research is a preliminary study, additional research is required because
there were no internal standards, and there were no replicates. A search
of the medical literature showed that gamma-terpinene is a skin irritant,
whereas Z-ligustilide is a muscle relaxant. Z-ligustilide also has antiasthmatic
effects as well as anticholinergic effects. However, there is no clear
connection with the claimed medical effects.
| Hughes Sanders
November 4, 2002 Changes in Social Behavior in the Mantled Howler Monkey (Alouatta palliata) due to Infant Presence Mentor: Dr. Robert Eckstein |
|
Abstract: The mantled howler monkey
is a New World primate that ranges from Central to South America.
The conservation status of this species is currently listed as low risk
for extinction, perhaps due to the large demographic area that is covered
by howler monkeys. In 1997 a group of scientists working in collaboration
with the Nicaraguan government established the Ometepe Biological Field
Station. Ometepe Island is located in Lake Nicaragua, which lies
in southern Nicaragua. The purpose of my study was to determine the
influence of infants on female’s social relationships, in regards
to the amount of time spent in proximity to other members of the social
group. Previous studies show that both male and female howlers behave
aggressively towards infants. A focal animal sample with three-minute
time intervals was conducted. Data was collected on the distance
that both mothers and non-mothers maintained with other adult members of
the social group. The data show a significant difference (p<.0001)
between mothers and non-mothers proximity to members of the social group.
The data do not yield a significant difference (p=.5857) between mothers
holding their infants and mothers not holding their infants. The
results of this study suggest that mothers spend more time away from members
of the social group than non-mothers.
Kirkdale Guy
November 25, 2002
Fabric Dyes in the Asheville Sewage Treatment System
Mentor: Dr. J. Brock
Abstract: Fabric dyes are a means
of applying color to fabric. One method of dyeing fabrics is to submerge
the fabric in a dye solution allowing the dye to react with the fabric
leaving the fabric colored. Using the process of a dye bath produces an
excess of dye dissolved in gallons of water or dyeing medium. The waste
of the dyeing process is an issues because in Asheville North Carolina,
fabric dyes are legally dumped into the sewage treatment system which does
not filter to remove chemicals before the effluent is dumped into the French
Broad River. My objective was to develop a method using high pressure liquid
chromatography to analyze for the presence of the dye. My second objective
was to then develop a calibration curve for a specific dye and to analyze
for the presence and concentrations of the dye, if present. A set of standards
was created using dyes obtained from Lustar, a local dyeing company. The
standards were used to generate a calibration curve that was later used
to relate detector response to dye concentration. The limit of detection
of the instrument was calculated by analyzing water blanks to correct for
background noise. The limit of detection was determined to be 6.0 parts
per billion (ppb). From the effluent samples collected at the sewage treatment
plant, the concentration of Remazol blue fabric dye was below the 6.01
ppb calculated detection limit in all samples collected. There was however
a red compound present in the effluent that could be isolated using solid
phase extraction. The red compound produces a wavelength of 254 nm.
Alice Baker
December 2, 2002
Effects of Decreased Deworming on the Warren Wilson College Beef
Cattle Herd
Mentor: Dr. Jeff Holmes
Abstract: Warren Wilson College beef
cattle are raised on a rotational grazing system. This rotational
grazing may limit the transmission of parasitic worms, if the worm load
on the pastures is already low. This experiment was conducted to
determine if worm loads are higher in cattle dewormed once a year rather
than twice a year, and to determine if weight gains were higher in cattle
dewormed twice a year rather than once a year. This decreased deworming
may be beneficial in slowing the development of resistance in nematode
populations, may reduce the impact on the environment (dung beetle larvae),
and may reduce the cost of deworming to farmers. The yearling cattle
showed no significant difference in weight gains (p-value 0.59), the adult
cows produced no significant difference in weight change (p-value 0.86),
and the calves showed no significant difference in weight gains (p-value
0.70). The comparison of egg concentration was also not statistically
significant (p-value 0.65) between cattle dewormed once a year versus twice
a year. These results do not necessarily suggest abandoning the use
of synthetic dewormer on Warren Wilson College cattle, but they do suggest
a decreased deworming program that includes increased health monitoring
may be acceptable.
Steven M. Ritt
January 27, 2003
Glycoalkaloids in the Nightshade Family
Mentor: Dr. Dean C. Kahl
Abstract: Folklore has long considered
the nightshade family (Solanaceae) of plants to be poisonous, and there
are compounds present in these plants thought to aggravate the conditions
of arthritis. This problem may be due to the presence of the neurotoxins
a-solanine and a-chaconine in these plants. The purpose of this project
was to develop a method to analyze glycoalkaloids in tomatoes. Analysis
of these glycoalkaloids was first performed using the Spectra Physics High
Performance Liquid Chromatograph (HPLC), but the instrument was not sensitive
enough for the detection of glycoalkaloids. Analysis was then continued
using a newer and more sensitive instrument, the Shimadzu HPLC. However,
there were numerous technical difficulties with the Shimadzu HPLC, and
the detection of a-solanine and a-chaconine was not possible using this
instrument. Given the problems with the HPLC instruments, a simple
and rapid means of analysis using thin layer chromatography (TLC) was developed.
Preliminary results showed that the glycoalkaloids, a-solanine and a-chaconine,
could be separated from the aglycone, solanidine, using reverse phase TLC
plates and an acetonitrile- ammonium phosphate buffer (50+50). However,
the glycoalkaloids, a-solanine and a-chaconine could not be separated.
These results suggest that thin layer chromatography can be used to identify
glycoalkaloids in plants of the nightshade family.
Melissa Meyer
February 17, 2003
Pyrolysis of Newspaper and Magazines
Mentor: Dr. Dean Kahl
Abstract: Extensive research has been
done on the pyrolysis of wood. Newspaper and magazines contain the
same materials as wood and may potentially yield the same products from
pyrolysis. This method could be used as most of the products have
a potential for fuel and chemicals. In addition, this technique could be
used to decrease the amount of paper waste. The purpose of this project
was to determine whether newspaper and magazines could be converted to
charcoal and chemicals using pyrolysis. This experiment was done
by heating newspaper and magazines in a distillation apparatus under nitrogen.
The products from this experiment include charcoal, an aqueous phase, an
organic layer, and gases. The charcoal was burned in a furnace to
determine residual ash. There was no significant difference between
the charcoal yield of newspaper 42% and magazine 49% giving a p-value of
0.0606 using the Mann-Whitney test. There was also no significant difference
between the amounts of gas, water, and organic products between magazine
and newspaper with p-values 0.6650, 0.0606, 0.0606 respectively.
The residual ash shows a significant difference between the newspaper (0.08)
and magazine (1.03) with a p-value of 0.0265. This fact means residual
ash should not be a problem in charcoal production. The charcoal,
gas, organics, and water from this experiment produced yields comparable
to previous research but using a low-tech alternative. This method
could be used in less developed countries to reduce deforestation while
making use of paper waste.
Rachel Horn
Feb 24, 2003
Classification of Clay and Archaeological Pottery byChemical
Composition
Abstract: How much can we learn about
a potsherd through chemical characterization? Was this potsherd brought
here from another village? Where did the Native Americans collect
the clay they used to make their pottery? How much does the clay
change chemically when it is fired? These questions can all be answered
using chemical methods. This study measured the chemical composition
of clays and pottery from eight different sites.
| SampleGroup | Location |
| 1 | Big Bottom Field Clay |
| 2 | Horse Pasture Clay |
| 3 | Ballfield stream Clay |
| 4 | Fired Ballfield Clay |
| 5 | Early Macon County Site Potsherds |
| 6 | Late Macon County Site Potsherds |
| 7 | Warren Wilson Site Potsherds |
| 8 | Burke County Site Potsherds |
All samples were soaked in 1M HCl for one week. The concentrations of Ca, Ba, Sr, Mg, and Fe were measured using Inductively Coupled Plasma ( ICP). Multiple Analysis of Variance (MANOVA) showed that the three clays (samples 1-3) could be distinguished from the pottery and each other. In addition pottery from different time periods at the Burke site (5, 6) did not differ (P value 0.09). However MANOVA did not clearly distinguish potsherds from different sites (5+6, 7, 8). Multivariate analysis can give us clues about chemical patterns in the potsherds. Principal Component analysis uses functions, which account for almost all the variability in the data set to look for patterns in the data. Here are the actual functions for the principal component analysis graph.
PC1 = 0.004*lnFe-0.552*lnCa-0.815*lnBa-0.172*lnSr-0.023*lnMg PC2=0.542*lnFe+0.090*lnCa-.0193*lnBa+0.557*lnSr+0.592*lnMg
These functions create a scatter plot which
allows the data to be visually represented. Composition patterns
emerge in this scatter plot, indicating that chemical composition can be
used to suggest the source of clay for a pot. Therefore, Native American
potters at the WWC site apparently did not use any of the clay sources
sampled here. With enough samples this method could source a single
potsherd to a single clay source.
Nathan Jones
March 3, 2003
Metals in Urine of Smokers and Nonsmokers
Mentor: Dr. John Brock
Abstract: Smoking of tobacco and non-tobacco
products produces exposure to numerous toxins. Many of these compounds
promote tumor cell growth. Smoking-related toxins include carbon monoxide,
tar, nicotine, polyaromatic hydrocarbons, and cadmium. Cadmium, a heavy
metal, has been shown to be toxic at low levels of exposure. Smoking is
the primary source of cadmium exposure in the general human population.
Individuals who smoke heavily on a regular basis have been shown to exhibit
elevated levels of urinary cadmium compared to nonsmokers. The purpose
of this experiment was to test if differences exist in urinary levels of
metals between populations of nonsmokers, smokers of tobacco products,
and smokers of non-tobacco products. Individuals participated anonymously
in an experiment in which 24-hour urine samples were collected and analyzed
using various analytical instruments. The samples were analyzed for metal
concentrations and the data was analyzed using both parametric and nonparametric
tests. The p-values from the analysis suggested no difference between the
means for any of the analytes. The data implies that smoking does not tend
to increase urinary levels of cadmium, mercury, or chromium. However, the
results may be limited due to the small, highly variable human populations.
Sarah Stokes
March 3, 2003
Toxicity of dibutyl phthalate to zebrafish (Danio rerio) embryos
Mentor: Dr. Jeff Holmes
Abstract: Phthalates are a class
of chemicals manufactured on a global scale in large quantities.
They are used in numerous products ranging from plastic goods to personal
care products. Animal testing has demonstrated significant toxicity
of phthalates, especially in the early stages of development. Zebrafish
embryos develop quickly, outside the body, and have transparent embryos,
which makes them suitable organisms to use as models for vertebrate development.
The purpose of this experiment was to determine the lethal dose of phthalates
for zebrafish embryos. To do this, dose-response curves were constructed
for the percent mortality of zebrafish embryos to dibutyl phthalate and
LD50 concentrations for 24 and 48 hours of exposure were calculated.
The average LD50 concentration for 24 hours was 1.2 ppm and the average
LD50 for 48 hours was 2.4 ppm. The concentrations of dibutyl phthalate
found to be lethal to zebrafish in this experiment are comparable to the
concentrations of phthalates to which humans are exposed. This result
may have important human health implications, especially for developing
fetuses.
Tamara Todd
March 10, 2003
Conjugated Linoleic Acid in Egg Yolks from Chickens at the Warren
Wilson College Farm
Mentor: Dr. Victoria Collins
Abstract: Conjugated linoleic acid (CLA) is an isomer of the
18 carbon unsaturated fatty acid linoleic acid. CLA is found in products
from ruminant animals. CLA has been shown to be anti-mutagenic, anti-carcinogenic,
anti-atherosclerotic, anti-diabetogenic, and can reduce adipose tissue.
The first objective of this study was to produce eggs enriched in CLA by
feeding a CLA supplement to hens. The second objective of this study was
to compare the fatty acid composition of eggs from chickens living indoors
and chickens with access to the outdoors. Laying hens were divided
into four indoor pens and four outdoor pens. All eight pens were fed a
control diet (standard layer diet + 1% soybean oil) for three weeks. Eggs
were collected during the third week and egg yolks from each pen were pooled.
All eight pens were then fed the experimental diet (1% CLA) for three weeks.
Eggs were collected during the third week and yolks were pooled for each
pen. Fatty acids were extracted from the yolks, trans-esterified,
and analyzed by gas chromatography. Fatty acid composition was analyzed
by two way ANOVA. The two factors, diet and housing, showed no significant
interaction. The effect of diet on egg composition was significant (p<0.05)
for all fatty acids measured. Saturated fatty acids increased and
unsaturated fatty acids decreased when CLA was added to the diet. The relative
amount of CLA increased from 0% of total fatty acids to ~1.5% of total
fatty acids upon CLA supplementation. The effect of housing on fatty acid
composition was only significant for stearic acid, which was lower in eggs
from outdoor chickens (p<0.05). All other fatty acids showed no significant
difference between the indoor and outdoor groups (p>0.5). Hens fed
1% CLA produced eggs containing approximately 30 mg of CLA per egg.
For producers of “designer eggs”, supplementing with
CLA may be profitable. The effect housing on fatty acid composition needs
further exploration.
Sarah Leavitt
March 10, 2003
The effect of the stress of being handled on the growth of piglets
on the Warren Wilson College farm
Mentor: Dr. Robert Eckstein
Abstract: Pork sales are a major profit
on the Warren Wilson College farm. Barbeque hogs are sold for $0.75/lb
of live weight at slaughter. Previous studies have found that various forms
of stress on livestock can affect growth and development, and thus the
profit of the farm. The objective of this research was to determine
the effect of handling stress on the growth of piglets on the Warren Wilson
College farm. The hypothesis was that handling stress would have
an effect on weight gain. There were 4 sows in the research, and
it was a repeated measure design study. Two litters from each sow,
one in February and one in July, were used in this study. To control
for variability among sows, one litter was in the control treatment, and
the other the experimental treatment. The piglets in the control
treatment were not handled at any time except for routine husbandry handling.
The piglets in the experimental treatment were handled individual for two-minutes
each, three times per week, for seven weeks. Their mouths were held
gently closed. Three weights were collected for each piglet over the seven
weeks. The first weight was collected at one day old, the second
at five weeks old, and the third at seven weeks old. A paired t-test
was run on the average weight gain per piglet for each sows control versus
experimental litters. The p-value was 0.49, which suggests there
was no significant difference. A paired t-test was run again, excluding
one sow. She killed all piglets except two in her control litter.
All other litters in the study had between 6-8 piglets. The p-value
for the paired t-test excluding her data was 0.14 suggesting there was
no significant difference between the handled piglets and control piglets.
These results suggest no support for the hypothesis that handling stress
would effect weight gain.
Scott Steinbrueck
March 31, 2003
A Comparison of Terrestrial and Aquatic Tardigrada
Mentor: Dr. Paul Bartels
Abstract: Tardigrades were first discovered
in 1773. They comprise their own phylum, Tardigrada, which is a sister
group of the arthropods. They are one of the lesser-known phyla.
While over 900 species have been identified, very little is known about
their basic ecology. The objective of my research was to determine
if there were any morphological differences between terrestrial and aquatic
tardigrades. It is hoped that this study will suggest possible avenues
for future research into adaptations for terrestrial and aquatic living.
Two comparisons were done; one intraspecific, within the species Macrobiotus
richtersi, and one interspecific, within the genus Isohypsibius.
Tardigrades were isolated from their habitat and preserved in jars of alcohol.
The jar contents were then placed on a gridded petri dish and organisms
were removed with an Irwin loop. Specimens were mounted onto microscope
slides using Hoyer’s Medium. Measurements were taken for
body length and width, buccal tube length and width, and claw length.
All measurements were done with an ocular micrometer on a phase-contrast
microscope. Within the intraspecific comparison, significant differences
were found in body length (p value = 0.030), body width (p value = 0.029),
buccal length (p value = 0.005), and buccal width (p value < 0.0001).
In this comparison, aquatic specimens were smaller than terrestrial specimens.
Within the interspecific comparison, the only significant difference found
was in the claw length measurements. The aquatic species had longer
claws than the terrestrial species. The differences within the intraspecific
comparison of Macrobiotus richtersi may exist for two reasons, one functional
and one nonfunctional. The functional reason suggests that aquatic
specimens may have been smaller because of adaptations to stream life.
The nonfunctional explanation is that the aquatic specimens may have been
collected at an earlier instar stage and were therefore less mature than
the terrestrial specimens. The longer claw length found in the interspecific
comparison of Isohypsibius may be an adaptation to help the organisms grip
to surfaces in running water.
Arlette Rogers
March 31, 2003
Sex Ratios in Loggerhead Sea Turtles as a Function of Incubation
Duration and Dune Temperature
Mentor: Dr Louis Weber
Abstract: Loggerhead sea turtles (Caretta
caretta) are listed as threatened under the Endangered Species Act of 1973
(ESA). As a result the turtles are federally protected and conservation
efforts have been devised to help increase the population. Sex in
sea turtles is determined by temperature during the middle third of incubation.
This phenomenon is known as temperature dependent sex determination (TSD).
Eggs in nature experience a range of temperatures and it is not clear whether
the average of a changing temperature produces the same effects as a constant
temperature of the same value. This is known as the transitional range
of temperature (TRT). Temperature has two important roles on sea
turtle eggs and their development. Warmer temperatures result in
greater percentages of females and shorter incubation durations.
My objective was to first look at the TRT for individual nests laid in
the summer of 2001 on South Island, South Carolina and determine if there
is a correlation between incubation duration and sex ratios. I also
compared temperatures taken from the flat and the top of a sand dune on
South Island to determine whether nest relocation could effect sex determination.
StowAway TidbiT Tempeature Loggers were buried 50 cm below the surface
of the sand at six different dune sites on the island. There were
three loggers at each site, one at the flat of the dune, one in the middle,
and one at the top. Temperature readings were taken every 2.5 minutes
during the nesting season from May 22 to September 11, 2001. The
average temperature was taken for the second trimester of each nest and
plotted in a graph against incubation duration. It was found that
there was no detectable correlation between average second trimester temperature
and incubation duration. I believe this result is an outcome of a
short nesting season, a small sample size, and the chaos of the natural
world as opposed to a controlled setting. A distinguishable difference
was found in the average temperatures taken from the flat and top of a
sand dune. It is clear that the relocation of nests may have an impact
on the sex ratio of loggerhead hatchlings on South Island and should be
taken into consideration when assessing conservation efforts for the species.
SarahKeith Valentine
April 7, 2004
Salinity Effects on Microbial Processes within and below the
Wetland Rhizosphere
Mentor: Dr. Mark Brenner
Abstract: Three microbial processes
dominate carbon metabolism in anaerobic wetland sediments. These processes
are iron(III) reduction, sulfate reduction, and methanogenesis. Each
of these processes uses carbon as an energy source, which results in competition
for the supply of organic carbon. In the freshwater wetland they studied,
Roden and Wetzel (1996) found that the presence of roots enhanced iron(III)-reduction
and suppressed methanogenesis. The objective of this study was to
determine if the findings of Roden and Wetzel (1996) are reproducible
in a different wetland system, and also to determine whether their findings
will be affected by the presence of sulfate in the system. This was
done by monitoring rates of iron(III) reduction, sulfate reduction and
methanogenesis in soil cores taken both below and within the rhizosphere,
and from both a saltwater (Jack Bay) and a freshwater (Jug Bay) marsh.
Fe(III) reduction rates were determined using a colorimetric procedure,
sulfate reduction rates were determined using a radioisotope, and methanogenesis
was measured using a gas chromatograph. The results were compared using
a nonparametric paired t-test. While the general trends for microbial
processes found in Jug Bay (fresh) were similar to the freshwater site
that Roden and Wetzel studied, statistical analysis showed that there was
no significant difference in microbial processes below versus within the
rhizosphere for Jug Bay (p-values > 0.31). There was also no significant
effect of roots found in Jack Bay, the saline site (p-values > 0.53). These
results suggest that there is a lot more research to be done in this area,
examining different factors that affect the importance of the microbial
processes in wetland soil.
Savanna S. Cashion
April 14, 2003
Kickboxing and Respiratory Physiology
Mentor: Dr. Victoria Collins
Abstract: Aerobic kickboxing has taken the competitive high-energy moves of competitive martial arts and incorporated them into a functional group workout to fit a variety of fitness goals and capacities. Aerobic activity trains the heart, lungs, and cardiovascular system to process and deliver oxygen quickly and efficiently to every part of the body. A goal of many athletes is to improve their ability to catabolize fat for fuel. By measuring the respiratory quotient (RQ), the ratio of carbon dioxide produced to oxygen consumed, it can be determined when an individual shifts from burning carbohydrates to burning fat. The RQ of fat is 0.7. The RQ of a carbohydrate is 1.0. The amount of ATPs used in ratio to carbon dioxide produced for carbohydrates is 6.3. It is 8.1 for fat. If the same amount of ATP is used, a person should produced less carbon dioxide when burning fat than when burning carbohydrates.
This study investigated the respiratory quotient
of six women in a kickboxing class for four weeks to determine if the training
program offered a successful pathway for bodily fat reduction. Respiratory
gases were collected at the start, middle, and termination of each 1-hour
exercise session. Samples were collected from some subjects 30 minutes
after the workout to investigate the post-exercise oxygen consumption.
Oxygen measurements were not reliable. Carbon dioxide measurements
were reasonable and reproducible. The carbon dioxide output was not
significantly different among individuals or sampling periods. However,
average carbon dioxide output over the entire session differed significantly
(p<0.05 by Kruskal-Wallis) over the four-week study period. Average
carbon dioxide output decreased significantly during the study, which suggests
an improvement in fat catabolism.
Tom Gilfoy
April 14, 2003
The effect of dietary supplementation of red worms (Lumbricus
rubellus) on a tilapia (Tilapia nilotica) and sweet basil (Ocimum
basilicum) based recirculating hydroponic/ aquaculture system.
Mentor: Dr. Mark Brenner
Abstract: Human beings consume large amounts of aquatic organisms.
This has placed a strain on our ocean’s ability to keep up with
consumer demands. Aquaculture presents itself as a viable alternative
to traditional fishing tactics, but the feed used in aquaculture production
is comprised of ocean bio-mass, thus adding to the problem of over fishing.
In search of a food alternative for the culture of fish and sweet basil
in recirculating, aquatic/hydroponic systems, Tilapia nilotica were supplementally
fed red worms as opposed to a purely traditional dry feed diet. There
were six systems in all, three of whch were fed 4g of traditional dry feed
and three that were fed 2g dry worms and 2g traditional dry feed.
Basil was grown with effluent from the corresponding systems. After
a one-month period of time there was no significant difference in weight
gain of Tilapia nilotica fed the different diets with a P-value of 0.3898.
Basil growth for a one-month period with effluent from the two different
systems also showed no significant difference with a P-value of 0.4799.
Six aquatic/hydroponic systems were successfully set up in the Warren Wilson
College greenhouse. Because there was no significant difference between
the two diets, red worms appear to be a more economically and environmentally
viable diet for fish in small-scale aquaculture.
April 28, 2003
Habituation times in the sensitive plant, Mimosa pudica
Mentor: Dr. Jeff Holmes
Abstract: The sensitive plant is so
named because of its dramatic thigmonastic response. When stimulated
by heat, wind, rain, or touch it rapidly folds its leaves and collapses
its petioles, returning them to their original position after several minutes.
Despite extensive research, M. pudica's methods of stimulus transmission
and perception remain unclear. If stimulated repeatedly, M. pudica
will cease to respond to a specific stimulus and begin to re-open its leaves.
This is known as habituation. It was my objective to determine whether
M. pudica’s habituation time would change if the plants
were habituated every day for seven days. I showered the plants each
day until every one habituated, recording the time it took for each to
do so. I removed one plant for a control, habituating it only on
the first and last day, while the others were subjected to the same habituation
protocol every day for seven days. I analyzed my data with a graphical
regression test and obtained a p-value of less than 0.0001 and an r-squared
value of 0.5435. There was a significant decrease in habituation
time, suggesting that habituation times can be influenced by training or
history. This may have implications for understanding the mechanism
of habituation, which has previously been unclear.
Molly Hubbard
April 28, 2003
Midwifery in WNC: A Study of 100 Home Births
Mentor: Dr. Robert Eckstein
Abstract: Midwives have traditionally attended women at birth.
There are an estimated 6,000 traditional midwives and 7,000 certified nurse
midwives in the US. In North Carolina and 16 other states, the practice
of traditional midwifery is illegal .The data was obtained through survey
from four traditional midwives and one certified nurse midwife.
The first objective of this study was to determine the frequency of
specific complications and interventions for 100 low risk home births attended
by five local midwives. The study found the following frequencies: 80%
of the babies experienced no complications, 79% of the mothers had no complications
in labor, 65% of the mothers had no third stage complications, and 74%
of all births had no interventions used during labor. The total intervention
frequencies were as follows: Amnitomy 12%, hospital transfer 9%, vacuum
assisted 0%, use of Prostaglandins or Syntocin 9%. The total number of
labor complications per 100 births were as follows: delayed rupture of
the membranes 6%, prolonged labor-exhaustion 11%, prolapse of the umbilical
cord 1%, fetal distress 3%, Meconium staining 14%. The total number of
third stage complications per 100 births were as follows: postpartum hemorrhage
8%, retained placenta 5%, and shoulder distochia 8%. Total complications
to the baby per 100 births were as follows: 9% jaundice, 5%transient tachypnea,
Meconium aspiration 1%, infant resuscitation 5%, There were no babies that
experienced fractures or neonatal infection in the study.
The second objective of this study was to determine if the frequency of these complications and interventions was affected by a midwife’s years of experience. The study found a significantly lower use of interventions among midwives with more years of experience as compared to midwives with less years of experience. There was no association between the frequency of complications and the length of midwifery practice.
Abstract: Phthalates are industrial chemicals used in many consumer products. Recent studies have shown that phthalates disrupt reproductive tract development in the male rat and widespread exposure has been found among adult humans. Phthalates have been found in every part of the environment and create an urgent need for human exposure assessment studies because of their possible teratogenic, mutagenic, and carcinogenic affects. The objectives of this study were, to determine and compare MBP and MEHP concentrations in Copenhagen waters and to compare the results of this study to other water studies. The monoesters were collected through convenience water sampling. Solid phase extraction was used to concentrate the samples. Liquid chromatography with coupled mass spectrometry (LC-MS/MS) was used to analyze the samples. Concentrations of both monoesters were found in all samples sites in Copenhagen. Untreated waters (i.e. canal, lake) had higher concentrations than treated waters (i.e. tap, bottled, control). Measuring the pooled monoester concentrations in the surrounding environment allow researchers to estimate the quantities of phthalates being metabolized by organisms. While little is known about phthalate health effects in humans, this type of research can eventually lead to a better understanding of phthalate exposure.