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J. R. Patton
Student Representative at the Geological Society of America Poster Presentation
Bonny Batt, Beth Brady, Elie Braun, Gwen Erickson,
Daisy Finch, Colin Hughes,
Brett Ingles, Lora Kiger, Noel Liner, Michelle Murt,
Ozzie Ordaz, Alexa Ozzello-Reed,
Jay Patton, Justin Reeves, Russ Seghetti, Chris Sheridan,
Nate Smith, and Jay Stallman
Camp Participants
Ken Aalto (Humboldt State University), Joanna Redwine (Humboldt
State University), and
Russell Shapiro (Bowdoin College)
Camp Teaching Staff
Department of Geology, Humboldt State University
Paleozoic formations mapped, all marine, include crinoidal grainstones and wackestones of the Joana Limestone (Mississippian), mixed siliciclastics of the Antlerland-derived Chainman and Diamond Peak Fms (Mississippian), carbonate mudstones, wackestones and grainstones of the Ely Limestone (Pennsylvanian), and carbonate mudstones (with craton-derived quartz silt), wackestones and grainstones of the Arcturus Fm (Permian). Diamond Peak coarse clastics exhibit both graded bedding and cross-bedding. Tertiary units include basal red siliciclastics interpreted as fanglomerates, succeeded by finely laminated and interbedded white, tuffaceous calcareous lacustrine sandstone and mudstone of the Sheep Pass Fm. Younger volcanic and volcaniclastic rocks include several ignimbrites, basalt and basaltic andesite flows and dikes, vitrophyre flows and a variety of airfall tuffs, epiclastic sandstones and lahar-emplaced diamictites. At least three generations of Quaternary fan deposits are present.
Unconformable relations suggest that Paleozoic formations were folded prior
to deposition of basal Tertiary sediments. Folds trend north-south, have wavelengths
of one half to several km, vary from open and generally upright to tight with
east-vergent axial surfaces, and plunge moderately both to the north and south.
The tightest structures, on Antelope Mt. and the southern half of Joana Ridge,
exhibit fault-propagation fold geometry with overturning to the east. A strange
mesa (Efin Mesa), at the north end of Joanna Ridge, exhibits excellent fault-bend
fold geometry with east-west trending cross faults separating the two folding
styles along the ridge. East-northeast trending normal faults crosscut Tertiary
formations, and in turn are crosscut by north-south trending normal (Basin
& Range) faults, some of which offset Quaternary fans. On the southern
flanks of Joana Ridge, dense varicolored jasperoid is developed along the
Joana-Chainman Fm contact. However, on Efin Mesa extensive coeval (?) silicification
of flat-lying Diamond Pk. (Newark Valley sequence?) calcareous chert pebble
conglomerate, breccia and quartzose sandstone suggests that the zone of alteration
migrated upwards within the Chainman/Diamond Peak clastic wedge. The fault-bend
fold geometry of the mesa suggests that here a decollment is stepping up from
a deeper horizon to the Pilot Shale, which stratigraphically underlies the
Joana Limestone.
Sharon S. Chadwick and Mary H. Kay
The Library, Humboldt State University
The Library at Humboldt State University has had a long history of complaints
from staff and library users about its poor air quality. These problems were
exacerbated when an addition with its own HVAC system was built in 1977. With
California's increasingly worse budget problems and the resultant decrease
in maintenance of the HVAC systems, the indoor air quality deteriorated greatly
in the late 1980's and early 1990's. Each time the carpeting was replaced
or painting was undertaken in the Library, several employees would become
ill. The first author was one of the more severely affected and was out on
disability for the academic year 1991/92 when a major recarpeting and repainting
project was carried out. Changes in the Library administration brought a commitment
to finding out the underlying cause(s) for the indoor air pollution and taking
steps to resolve the problem. The ongoing process will be described in this
poster.
Phyllis Chin
Department of Mathematics, Humboldt State University
Over the last 10 years, the presenter has worked with a team of university mathematicians and K-12 teachers to improve the content and pedagogical knowledge and teaching in a large rural area of Northern California. Two funding sources have sponsored on-going interactions between the mathematicians and teachers.
RAMP (Redwood Area Mathematics Project) is an ongoing project funded by the State of California and has as its major goals to enhance the teaching effectiveness of K-12 teachers and to develop and support teacher-leadership. University mathematics faculty members provide mathematics content while K-12 teachers share ideas for classroom applications of the content and learn about the mathematics that precedes and follows what they teach at their grade levels.
PROMPT (Professors Rethinking Options in Mathematics for Prospective Teachers) was funded by the United States National Science Foundation. The participants in Project PROMPT are mathematicians from universities who teach math content courses to K-8 teachers. Its primary goal is to improve the mathematical preparation of teachers by involving participants in a variety of ways of teaching and learning and evaluating learning.
At the heart of both projects is a residential program, containing a mixture of content presentations and pedagogical discussions. Participants are treated as professionals with valuable ideas to share. Professors and K-12 teachers alike have benefited from their interactions and all report changes in what and how they teach.
The effectiveness of these projects results from participants:
o learning significant mathematics in cooperative settings
o evaluating new K-12 curricular materials
o discussing the content and methods they use in teaching
o exploring a variety of assessment techniques
o examining the role higher education should play in facilitating changes
in mathematics education in the United States.
These experiences are particularly important for mathematicians, since they were successful in learning from lectures on mathematics and thus do not always recognize the necessity of alternative methods to instruct less mathematically inclined students. For teachers, the interactions with mathematicians led to increased content competence.
This poster will display a summary of the philosophy and effects of the projects
along with photographs of some RAMP and PROMPT activities.
M. A. de Angelis, M. E. Torres, J. McManus
Department of Oceanography, Humboldt State University
Continental shelves have been identified as sites for a variety of cold seeps,
where release of fluids and gases from sediments to oceanic bottom water occurs
as the result of tectonic compression of sediments. Frequently, these seeps
are characterized by elevated levels of methane. The quantification of the
methane released from seeps or to oceanic bottom water is important in determining
the oceanic methane budget as well as providing an upper limit to the amount
of methane that may eventually be released to the atmosphere from continental
shelves where it may contribute to global warming. Equally important in determining
the contribution of seep methane to the atmosphere is the microbial oxidation
of methane within seep sediments and the water column into which the methane
is being injected. The control of microbial methane oxidation at seep sites
is not well understood. The study reported here examined microbial methane
oxidation activity in sediments and near-bottom water at methane seep and
non-seep sites within the San Clemente basin in order to gain a better understanding
of the role of methane oxidation in determining methane fluxes at such seeps
and possible controls on the rate of microbial methane oxidation in such systems.
Caroline E. Noha and James L. Dupree
Department of Psychology, Humboldt State University
Little research has been conducted to examine the differences in romantic love between persons identifying as homosexuals and heterosexuals as well as between male and female homosexuals. This study explored such potential differences by administering the Hendrick's Love Attitude Scale (LAS) to 136 subjects ranging in age from 18 to 74. The final self-identified subject pool consisted of 34 heterosexual men, 32 homosexual men, 35 heterosexual women, and 35 homosexual women. This study was a 2X2 factorial design. Subjects were elicited from both a university and community population. The LAS is probably the most commonly used and psychometrically evaluated measurement of romantic love. It is a 42-item questionnaire intended to measure six different styles or approaches to love.
As predicted, no significant differences were noted between homosexual and
heterosexual respondents, suggesting that romantic love issues are similar
between groups. One gender/orientation interaction was noted. Heterosexual
men and homosexual women endorsed Mania more than other respondents. Some
gender issues were noted, regardless of the sexual orientation of the subjects.
Women were found to endorse the lovestyle Eros more than men.
Eros is considered a more physical, passionate approach to love. Men endorsed
the lovestyle of Ludus more than women, which style is considered the more
game-playing, manipulative, and non-monogamous approach. Other issues such
as Storge (friendship), Pragma (practical), and Agape (selfless) failed to
emerge as contributing factors in trying to compare romantic love in these
populations. Implications for counseling homosexual couples were discussed.
It was suggested that the romantic love issues of homosexual couples seem
to be not significantly different than issues shared by heterosexual couples.
S. B. Edinger-Marshall, C.H. Yang, and D.E. Crowley
Department of Rangeland Resources and Wildland Soils, Humboldt State University
Microbiotic crusts cycle nutrients and protect soils against erosion. Fluctuations
in microbial communities in response to distrubance were studied using polymerase
chain reaction (PCR), denaturing gel gradient electrophoresis (DGGE) and DNA
sequence analyses. From the DNA DGGE profiles of 16S rDNA, five to seven dominant
bands were detected from different crusted soils. Community structure and
species composition was similar for several soil crusts. Fewer and different
DNA bands were observed in rodent-disturbed surface materials compared to
intact soil crusts, suggesting loss of structure and greater species evenness.
Tire tracks, while altering physical properties of crusts, did not appear
to alter bacterial communities significantly when compared to spatial variability
within either undisturbed or tire track sites. Results of
watering experiments on tire track sites and undisturbed sites will be discussed.
Mary B. Gruber, Kathy D. Munoz, Chris A. Hopper, and Robert Herb
Department of Psychology, Humboldt State University
The purpose of this study was to compare the effects of including versus
not including children's families in a six-week program to teach children
about exercise and nutrition. Six classes of fifth and sixth graders were
assigned to three different treatment conditions, with one fifth grade and
one sixth grade class in each condition. The three conditions were a school-and-home
treatment condition (n=50), a school-only condition (n=47), and a control
condition (n=51). In the control condition, children were given no additional
instruction in exercise or nutrition concepts beyond that provided in their
regular school curriculum. In the school-and-home and school-only conditions,
children were provided with additional in-class instruction and activities
relating to healthy exercise and nutrition habits. In the school-and-home
condition, the children's parents were also asked to participate by engaging
in specific exercise and nutrition activities at home with their family as
a "home team". Family teams received weekly points for completing
exercise and nutrition activities. Stickers and other rewards were presented
contingent upon family participation. Between-groups analysis of variance
showed significant differences at posttest, with pairwise comparisons showing
the school-and- home group scoring higher than the control group on tests
of flexibility, exercise knowledge, and nutrition knowledge, and significantly
lower than the control group on percent of calories obtained from fat. Repeated
measures analysis of variance showed that the school-and-home group with family
participation significantly increased their number of timed sit-ups and significantly
decreased their time to run a mile, while the school-and-home children with
no family participation did not. Repeated-measures analysis of variance indicated
that only the control group showed a significant pretest to posttest increase
in skinfolds, while the other groups showed no significant change. The participating
parents showed significant pretest to posttest improvements on the flexibility
and sit-ups tests, and a significant reduction in their intake of saturated
fat. Parents showed no significant change in exercise and nutrition knowledge,
but the individual parents' degree of change in knowledge scores did correlate
significantly and positively with those of their children. The "home-team"
approach was effective in improving some fitness components of children and
their parents, indicating that the family unit can be effective in producing
lifestyle changes.
Jill Montre and Mary B. Gruber
Department of Psychology, Humboldt State University
The purpose of this experiment was to examine whether children's attractiveness
has a biasing effect on adults' ratings of their personalities. A pilot study
pre-determined a set of photographs of attractive and unattractive male and
female children to be used as visual stimuli in the study. The actual subjects
consisted of 100 male and 100 female college students. Each subject received
the same, identical written descriptive case history of a child. Along with
the written case history was attached a photograph from one of four conditions:
attractive boy, attractive girl, unattractive boy, unattractive girl. Each
subject also received a questionnaire asking them to rate their perception
of the child on a semantic differential scale for 20 personality attributes.
Analysis of variance indicated that the attractive children were rated as
significantly more intelligent, popular, carefree, happy, attractive, healthy,
honest, powerful, hopeful, competent, independent, sociable, and loved than
were the unattractive children. The attractive children were not rated as
significantly more aggressive, serious, moral, carefree, normal, emotional,
or funny than the unattractive children, however. In addition, the subjects'
ratings of the children's attractiveness were significantly and positively
correlated with the ratings of the children as intelligent, popular, moral,
carefree, confident, happy, normal, healthy, honest, powerful, hopeful, competent,
independent, emotional, sociable, and loved. Ratings of the children's attractiveness
were not significantly correlated with ratings of the children as aggressive,
serious, or funny. Factor analysis was used to condense the 20 adjective items
into four factor scales. A 2x2x2 analysis of covariance for attractiveness
of child, gender of child, and gender of subject, with age of subject as a
covariate, was performed on each descriptive scale. Results indicated that
the attractive children were rated higher than the unattractive children on
the Popular-and-Successful factor, the Powerful-and-Confident factor, and
the Honest-and-Wholesome factor. The attractive and unattractive children
were not rated significantly differently on the Carefree-and-Fun factor, however.
Those who work with children should be aware of the biasing effect of children's
physical attractiveness on adults' ratings of their personalities, since this
effect has implications for prejudicial treatment of children and for children's
self-esteem.
Lisa A. Carson and Mary B. Gruber
Department of Psychology, Humboldt State University
This experiment was conducted to evaluate the concept of psychological momentum,
which sport psychologists view as an increase in self-confidence and subsequent
performance which occurs as a result of perceived gains in a competitive situation.
Forty college students were each placed in apparent competition with a same-
sex confederate. Prior to each trial, subjects rated their degree of expectation
of winning, confidence in their ability, and anxiety about their performance
on the next trial. Three one-minute trials were given on a rotary pursuit
task of tracking a moving light with a hand-held stylus, and time on target
was recorded. After each trial, subjects were given fictitious feedback about
whether they had won or lost that trial. Subjects were randomly assigned to
four different feedback conditions, which were win-win, win-lose, lose-win,
and lose-lose feedback, given after the first and second trials respectively.
Subjects who were told they won showed significantly higher next-trial expectations
of winning, confidence in their ability, and actual motor performance scores,
compared to subjects who were told they lost, thereby supporting the concept
of psychological momentum. The win-win group showed the greatest overall first-to-third
trial increases in expectation of winning, confidence in ability, and actual
motor performance, while the lose-lose group showed the least. The win-lose
and lose-win groups were compared to test contrasting predictions of the primacy
effect, which predicts that a series with an initial win followed by a loss
provides more psychological momentum to a competitor than an initial loss
followed by a win, versus the comeback effect, which predicts the reverse.
While the lose-win group showed greater first-to-third trial increases in
expectation of winning and decreases in anxiety, the win-lose group showed
greater first-to-third trial improvements in actual motor performance. Thus
the results favor the comeback effect with respect to confidence, but favor
the primacy effect with respect to actual motor performance.
Jennifer Conn and Senqi Hu
Department of Psychology, Humboldt State University
Thirty-one subjects viewed an optokinetic rotating drum for 12 minutes in
one session and self-rotated around a vertical pole with eyes closed while
alternately flexing and extending the neck in another session. The self-rotation
session contained 6 trials (3 clockwise and 3 counter-clockwise rotations).
Each trial contained 20 cycles of self-rotations. The self-reported ratings
of nausea and symptoms of motion sickness were obtained for each session.
The subjects developed symptoms of nausea, sweating, dizziness, headache,
drowsiness, and changes in salivation in both drum rotation and self-rotation
sessions. However, the subjects reported higher ratings of nausea in the session
of optokinetic rotation than in the session of self-rotation around a vertical
pole. These results indicated that both optokinetic rotation and self-rotation
with eyes closed while alternately flexing and extending the neck are effective
means of inducing nausea and motion sickness.
Senqi Hu and Nicholas Herren
Department of Psychology, Humboldt State University
Thirty-six subjects' facial electromyographic (EMG) activities at the zygomatic,
corrugator, and levator labii (superioris/alaeque nasi) muscle regions were
recorded while they were acting self-generated emotions of happiness, anger,
fear, sadness, disgust, and surprise. The results showed that the EMG activities
at the levator labii region generated significantly higher power than those
at the corrugator region while acting out disgust (P < 0.01), the EMG activities
at the zygomatic region generated significantly higher power than those at
corrugator region while acting out happiness and surprise (p < 0.01), and
the EMG activities at the corrugator region generated significantly higher
power than those at zygomatic and levator labii regions while acting out anger,
sadness, and fear (p < 0.01). It was concluded that the negative self-generated
emotions were associated with increased EMG activities at corrugator muscles
and that the positive self-acting emotions were associated with increased
EMG activities at zygomatic muscles.
Senqi Hu and Kathryn A. Player
Department of Psychology, Humboldt State University
This study investigated the effects of different retention intervals on the
magnitude of optokinetic rotation-induced conditioned taste aversions (CTA)
in humans. Two experiments were conducted. In Experiment 1, 20 subjects were
divided into two groups: CS-UCS Group, drinking soybean milk (CS) was paired
with optokinetic rotation-induced gastric illness (UCS); and CS alone Group,
drinking soybean milk was not paired with optokinetic rotation. Results indicated
that two days after pairing soybean milk drinking with optokinetic rotation,
the subjects in the CS-UCS Group significantly reduced palatability to soybean
milk and consumption of soybean milk than those in the CS alone Group. In
Experiment 2, 40 subjects were divided into four CS-UCS groups with 1 day,
3 days, 5 days, and 10 days retention intervals between the session of pairing
soybean milk with optokinetic rotation and the session of re-tasting soybean
milk. The results revealed no significant differences among four groups on
palatability to soybean milk and consumption of soybean milk in the re-tasting
session. It is concluded that optokinetic rotation is an effective unconditioned
stimulus for CTA formation and that CTA has a retention period of at least
10 days.
Senqi Hu and Jason E. Scozzafava
Department of Psychology, Humboldt State University
The purpose of the present study was to observe the subjective responses
to odors of lavender and jasmine and associated facial electromyographic (EMG).
Twenty-nine subjects participated in the experiment. Electrodes were placed
on subjects' zygomaticus major, corrugator supercilli, and frontalis muscles
of the face to record facial EMG signals. The baseline EMG were recorded before
odor presentations. Each subject was then inhaled essential oils of lavender,
jasmine, and water while EMG activities were recorded. The order of the odor
presentation was counterbalanced. The subjective ratings of pleasantness were
also obtained after each odor presentation. The ratio of EMG power between
tasting and baseline periods was calculated in statistical analysis. One-way
analysis of variance (ANOVA) on the pleasantness scores indicated significant
differences among odors. Further comparisons with paired t-tests indicated
that the subjects reported significantly higher ratings of pleasantness to
jasmine than to water (t = 4.52, p < 0.001), and that the subjects reported
significantly higher ratings of pleasantness to lavender than to water (t
= 3.78, p < 0.001). However, a two-way within subjects ANOVA on ratios
of EMG spectral power between odor inhaling period and baseline indicated
that the odor main effect was not significant, F (2, 27) = 0.685, p < 0.51
and the EMG site main effect was also not significant, F (2, 27) = 0.93, p
< 0.46. It is concluded that that facial EMG activity at zygomaticus major,
corrugator supercilli, and frontalis muscles are not sensitive enough to reflect
the level of pleasantness to jasmine and lavender.
Katherine S. Neidhardt, Maya Brewer, Jennifer Conn, and Senqi Hu
Department of Psychology, Humboldt State University
Twenty subjects' palatability reports and facial electromyographic (EMG)
activities at the zygomaticus major, corrugator supercilli, and levator labii
(superioris/alaeque nasi) regions were recorded while they were tasting water
or pickle juice. The results showed that subjects reported significantly higher
ratings of palatability to water than to pickle juice. The EMG activities
at the levator labii region generated significantly higher power than those
at the corrugator supercilli region while tasting water. The EMG activities
at the levator labii region generated significantly higher power than those
at the corrugator supercilli region and those at the zygomaticus major region
while tasting pickle juice. It was concluded that the facial EMG activity
at the levator labii region was the most sensitive indicator of palatability.
Lumei Hui
Department of Psychology, Humboldt State University
The vertical-horizontal (VH) illusion involves two straight lines; a vertical line is placed perpendicularly to, and on, the center of a horizontal line, as an inverted letter T. Yet, of all the geometric illusions, it is one of the most fascinating for at least two reasons: First, the VH is one of the simplest geometric illusions among those discovered since J.J. Oppel coined the phrase "geometric optical illusions" (Oppel, 1854-1855). However, the illusory effect is very strong. Subjects have normally overestimated the length of the vertical line 15-20% in comparison to the horizontal line (Hui, 1992).Secondly, there has not been a convincing explanation put forward about it from the time the VH illusion was first alluded to in literature 150 years ago.
One popular hypothesis was based on the inappropriate constancy scaling (ICS) theory. The ICS theory proposed by Gregory (1963,1966) assumes that familiar features in a two-dimensional figure can function as depth cues, causing a constancy scaling process, and resulting in an illusory effect. Because the depth itself is not presented in a two-dimensional figure, the constancy scaling process is therefore inappropriate. Girgus and Coren (1975) suggested that the ICS theory could be used to explain the VH illusion. They proposed that the relative height of the vertical line in the inverted letter T figure functions as a relative-height depth cue. The "higher in" the two-dimensional plane an object is, the farther away in three-dimensional space it is perceived to be. Thus, the vertical line in the figure is perceived as representing an object receding horizontally away into the third dimension. Unfortunately, they did not find a way to test this hypothesis directly.
The present researcher proposed a new hypothesis. This hypothesis assumes that an inverted T figure evokes a three-dimensional representation with the vertical line representing a vertical object and the horizontal line representing a horizontal object, in which the former stands behind the latter in front of the viewer. The depth between the two objects is hidden from the viewer. Because the depth information is missing, the vertical line was heuristically overestimated in comparison to the horizontal line. In other words, the illusory effect is due to the content of the hidden spatial relationship, not due to a depth cue per say. According to this hypothesis, if the hidden depth hypothesis is valid, then a hidden spatial condition might be reconstructed in a three-dimensional condition.
For example, a subject sits behind a curtain with her viewing level controlled by a slot on the curtain. The subject views two wood sticks on a round platform: one stick lying horizontally in front on the platform and the other standing vertically behind. There were 18 different combinations of those paired wood sticks used, with lengths ranging from 9 cm to 12 cm. Nine of them had a distance of 1 cm between the two sticks and the other nine cases had a distance of 5 cm between the two sticks. The lengths of the two sticks in the various combinations were either equal or shorter or longer by one centimeter.
A subject's viewing level could be designed low enough that (s)he could not perceive the distance between a horizontal object and a vertical standing object resulting an inverted letter T figure perception. Thus, subjects in such hidden depth spatial conditions might overestimate the length of the vertical object in comparison to the horizontal object. However, when the subject's viewing level was designed high enough that (s)he could see the distance between the two objects, then the VH illusory effect in such an explicit depth condition might be reduced significantly.
Six randomly selected subjects participated in the experiment. Each subject was required to compare the lengths of two wood sticks for about eighteen combinations. For each combination, a subject's response had to be one of three choices: the vertical stick's length was (1) equal to, or (2) longer, or (3) shorter than the horizontal one.
Results indicated that (1) in the hidden depth condition, the subjects overestimated
the length of the vertical stick in comparison to the horizontal stick 68
times out of 72 possible cases; and (2) in the explicit depth condition, the
subjects overestimated the length of the vertical stick in comparison to the
horizontal stick 35 times out of 72 possible cases. The difference between
the two different spatial conditions were statistically significant (x2 =
29.37, df = 1, p < .001). Thus, the results supported the hidden depth
hypothesis for the VH illusion.
Jennifer F. Taylor
Department of Psychology, Humboldt State University
The unique needs of ethnic minority special education students have only recently begun to be addressed in educational programming. In 1995, the World of Difference (WOD) was initiated to facilitate the academic progress of elementary students designated as "Seriously Emotionally Disturbed" (SED) and "Learning Disabled" (LD), in the San Francisco Unified School District (SFUSD). In the SFUSD, 87% of SED/LD students identify as African-American, Latino/a or bi-racial; 75% are boys and all are considered "at-risk" for dropping out of the educational system.
WOD provides a three-prong approach to "culturally competent" education, including specialized cultural training for educators, multi-cultural classroom materials and facilitation of parent/caregiver involvement via monthly "team" meetings. In 1997, a multi-modal evaluation was developed to measure WOD impacts. Student records (n=65) were analyzed to determine whether differences would be found in academic achievement and absentee rates. Student, classroom team and parent/caregiver attitudes towards school and WOD were qualitatively assessed.
Results show significant overall increases in academic achievement (t = 6.39, p < .001) and significant overall decreases in absenteeism (t = 3.09, p =. 007). WOD student attitudes are remarkably positive- in 1998-1999, none (0%) of the students reported disliking school! Moreover, WOD student gains are being maintained, as no significant difference was found between the 1998 & 1999 academic achievement (t =.24, p = .82) or attendance (t = 1.95, p = .08) data. Strengths of these findings include the use of a multi-modal and culturally/learning-style sensitive methodology. Limitations include the lack of a control group (pre-WOD baseline measures were used) and that the evaluation was initiated two years after WOD began. The potential role of ethnic identity development is noted.
Notwithstanding methodological imperfections, WOD is making a "World
of Difference" for ethnic minority SED/LD students and appears to be
a program worthy of replication. Unfortunately, USDOE funding has ended. While
new funding is being sought, the future of WOD in current and potential classrooms
is uncertain.
Mimi Black, Amanda Ellsmore, Carol O'Brien, and J. Varkey
Department of Biological Sciences, Humboldt State University
The genetic and phenotypic characterization of spermatogenesis genes in the
free-living nematode, Caenorhabditis elegans, is used to understand
the molecular basis of male specific meiosis. Reverse genetic techniques are
being used to analyze mutations in the early acting spermatogenesis genes
spe-30 and spe-25. Both male and hermaphrodite worms lacking
the functional gene products SPE-30 and SPE-25 are sterile.
Even though meiotic spindles are organized in the mutant spermatocytes and
actin organization appears normal, chromosome segregation is defective resulting
in multinucleated cells. Mutations in spe-30 and spe-25 have
also been shown to cause defects in the segregation of organelles during meiosis.
Precise genetic mapping of mutations in spe-25 on chromosome III (0.3mu
away from unc-36) and spe-30 on chromosome IV (0.75mu away from dpy-20
have been used to identify cosmid clones for transformation rescue analysis.
We report progress in the molecular characterization and detailed phenotypic
analysis of different alleles of the genes. Undergraduate research project
supported by HHMI and NSF.
Kim Brown, Kathleen Haines, and J. Varkey
Department of Biological Sciences, Humboldt State University
Here we report the genetic and phenotypic characterization of two previously
uncharacterized spermatogenesis-specific mutations in Caenorhabditis elegans.
Alleles it113 and it111 are mutations of different genes, both
of which cause sterility in males and hermaphrodites. Light microscopic observations
indicate that both mutant strains fail to produce functional spermatids due
to a defect in meiosis. Development of the male germ line does not proceed
beyond the spermatocyte stage. DAPI staining shows that the defective spermatocytes
of it113 mutants often have multiple condensed nuclei, similar in appearance
to haploid spermatid nuclei. However, mislocalized chromosomes have also been
observed in the defective spermatocytes, indicating a possible defect in chromosome
segregation. Immunolocalization studies reveal that in defective spermatocytes,
tubulin filaments fail to organize into recognizable meiotic spindles.
A possible role of it113 in the organization of centrosomes is being
investigated using centrosome-specific antibodies. There is no previous report
of a difference in the tubulin organization between mitotic and male meiotic
divisions in C. elegans, as observed in the it113 mutants. Conversely,
the spermatocytes of it111 mutant worms appear to have normal meiotic
spindle formation. However, chromosome segregation does not occur in it111
defective spermatocytes. The chromosomes of the defective spermatocytes appear
as condensed bivalents arrested in diakinesis of meiosis I. This phenotype
is very similar to spe-6 mutants, which also show meiotic chromosomal
segregation defects (Varkey et al., 1993). Ultrastructural analyses and mutation
screening for new alleles are in progress for both strains. Both mutations
have been mapped to Chromosome IV; it113 is on the left arm, approximately
4.4 mu from unc-17, and it111 is on the right arm, approximately
4.6 mu from dpy-20. Undergraduate research project funded by HHMI (71196-535002)
and NSF (MCB9734584).
The Development of Amino Alcohols as Acyl Transfer
CatalystsKjirsten A. Wayman and Tarek Sammakia
Department of Chemistry, Humboldt State University
We have developed two amino-alcohol systems as nucleophilic oxygen catalysts for acyl transfer reactions. These molecules bear an alcohol and a base in close proximity to facilitate the acylation and subsequent deacylation of the catalyst oxygen. Initial studies focused on 4-dialkylaminopyridines as the basic unit, with substitution at both the 2- and 6-positions in order to sterically deactivate the nucleophilic pyridine nitrogen. A second system was based on an ortho disubstituted benzene, consisting of a pyrrolidinomethyl substituent at one site and a hydroxyalkyl group at the other. A variety of catalysts of these types were prepared with varying acidities due to the presence of electron-withdrawing and electron-donating alkyl groups geminal to the hydroxyl group.
The importance of the hydroxyl group for catalytic activity has been established by blocking the hydroxyl group as the methyl ether. The methyl ethers of both the pyridine-derived and benzene-derived systems were found to be 94 and 930 times less active than the corresponding alcohol derivatives, respectively.
The inductive effect of the alkyl group plays a significant role in the reactivity of this class of catalysts. An electron-withdrawing group renders the hydroxyl group more acidic, more readily deprotonated and more reactive towards acylation, and a better leaving group for deacylation. As a result, trifluoromethyl substituted catalysts were found to proceed 4 and 40 times faster than the methyl substituted derivatives of the pyridine and benzene-derived systems, respectively.
The mechanism of this process is further revealed by the following observations.
Immediately after the reaction is initiated, the NMR spectra (used to monitor
the reaction progress) show the rapid decrease in the concentration of the
catalyst and the appearance of a new set of signals corresponding to the acylated
catalyst. The acylated catalyst remains as the predominant species until the
reaction nears completion and the catalyst reverts to its original unacylated
state. The system displays zero order kinetics with respect to the p-nitrophenyl
methoxyacetate throughout the majority of the reaction, suggesting a rate-limiting
deacylation of a steady state concentration of the acyl-catalyst intermediate.
The reaction is first order in catalyst, as expected. We are confident that
the dominant catalytic pathway proceeds via acylation-deacylation of the catalyst
oxygen.
Jeffrey White
Department of Biological Sciences, Humboldt State University
Most studies of rarity have been conducted from ecological and population
genetic frameworks while evolutionary history (phylogeny) has been largely
ignored. Macroevolutionary dynamics and underlying genealogical processes
may significantly contribute to explanations about the positions and rates
of rarity within some groups. Work presented here is a case study of rarity
from a phylogenetic framework and utilizes several new methods of analysis.
The study was framed around the hypothesis that high rates of diversification
coupled with local speciation generate phylogenetic clusters of rare species.
Evidence for this hypothesis was sought by addressing three testable questions:
1) Do diversification rates vary within the group? 2) Do rare
species cluster in the phylogeny? And 3) Are newly derived rare species more
frequent than expected? This study is based on the results of a morphological
cladistic analysis of 47 species of Astragalus 17 of which are
rare. Species range sizes, based upon published distributional-dot maps, were
quantified using ArcView GIS and the program "Minimum Cell Count"
written for this analysis. Significant evidence was found that diversification
rates vary within the group (Asymmetry Test, p<.05). Evidence of phylogenetic
clustering of rare species was found but not at a significant level (Mantel
procedure, p=.09). Rare species do not appear more derived that would be expected
by chance (Monte Carlo simulation, p=.32). Taken together, these results provide
equivocal support for the study hypothesis and may be due to a variety of
reasons. One possibility is that the phylogenetic scale (number of taxa in
this case) of the study system was not large enough. Other evidence is presented
which supports this conclusion. Overall, this work demonstrates a number of
new methods for the study of rarity with respect to phylogeny and the utility
of this general approach.
William F. Wood and James T. Welsh
Departments of Chemistry and Biological Sciences, Humboldt State University
The pronghorn, Antilocapra americana, is the sole living member of
the family Antilocapridae, a family consisting of living and extinct pronghorns
and the extinct merycodonts. Taxonomically, the closest living relatives to
the pronghorn are thought be the giraffes and the okapi. Gas chromatographic-mass
spectral (GC-MS) analyses of male pronghorn interdigital (hoof) gland secretion
showed it contains five major volatile components; tetradecanal, 1-tetradecanol,
(Z)-9-hexadecen-1-ol, 1-hexadecanol and 1-hexadecyl acetate. These
compounds are different from those found in previous studies on ungulate interdigital
glands from African antelope and members of the deer family (Cervidae). Most
of the secretions previously investigated contain known antimicrobial compounds.
Similarly, three of the compounds from the pronghorn, 1-tetradecanol, (Z)-9-hexadecen-1-ol,
and 1-hexadecanol, have previously been shown to have significant antibacterial
activity. The function of interdigital gland secretions has not been determined,
but these results suggest it may be the production of antimicrobial substances.
William F. Wood, Cynthia L. Archer, and David L. Largent
Departments of Chemistry and Biological Sciences, Humboldt State University
The banana slug, Ariolimax columbianus (Gould), a natural mycophagist
from the temperate rain forests of the Pacific Northwest, is selective in
the species of mushrooms in its diet. We observed this slug to taste and reject
sporocarps of the mushroom, Clitopilus prunulus. Tissue disruption
of mushroom sporocarps, similar to that expected by the exploratory feeding
of slugs, is known to greatly increase the number of volatile compounds. Comparison
of the volatile chemicals in whole, uncrushed, sporocarps and crushed (tissue
disrupted) sporocarps of C. prunulus showed the concentration of 1-octen-3-ol
to increase from 1.5 µg/g (non-crushed) to 28 µg/g (crushed).
1-Octen-3-ol is found in many species of mushrooms and has a "mushroom-like"
odor. In an antifeedant test, 6 out of 10 banana slugs rejected a 1.0 cm2
piece of lettuce treated with 8.3 µg of 1-octen-3-ol. This is the same
level found in the mushroom, so 1-octen-3-ol may be the reason slugs do not
eat this mushroom. (E)-2-nonenal has previously been identified in
the crushed tissue of this mushroom's sporocarp at 17 µg/g. In the antifeedant
tests, 85 µg of (E)-2-nonenal was used before 5 out of 10 slugs
rejected it, so it is not a major antifeedant in this mushroom.
Christopher N. Chervin and Robert W. Zoellner
Department of Chemistry, Humboldt State University
The common herb St. John's Wort (Hypericum perforatum) is often used
in the United States as an over-the-counter remedy for mild depression. The
photoactive component of this herb is hypericin, which exhibits potential
as a photodynamic therapy drug. Using the computational chemistry programs
PC Spartan Pro (Wavefunction, Inc.) and Gaussian 98W (Gaussian,
Inc.), hypericin and the two thiocarbonyl derivatives of hypericin have been
investigated. Both the mono-thiocarbonyl and di-thiocarbonyl derivatives,
and the optical isomers of the molecules, have been studied using semiempirical
and Hartree-Fock methods. Compounds containing thiocarbonyl groups are more
reactive than the carbonyl-containing parent compounds and thioketones are
highly colored even when the parent ketone is colorless. In addition to exhibiting
enhanced reactivity, thiocarbonyl derivatives of hypericin are expected to
be photoactive at different wavelengths than is hypericin itself. Finally,
carbonyl groups are readily converted to thiocarbonyl compounds using Lawesson's
Reagent, a phosphorus-sulfur heterocyclic system. Thus, the possibility exists
that the thiocarbonyl derivatives of hypericin may be able to be synthesized,
tying the calculations to real-world synthetic chemistry. The calculated structures
and properties of the thiocarbonyl derivatives of hypericin are reported.
Brief discussions of the implications these calculations have for syntheses
of the thiocarbonyl derivatives (in progress) are also included.
last modified 09/08/2008
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