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Photography
This year inaugurated the use of a new venue, the Kate Buchannan Room, for the Poster session. This allowed greater participation and nearly doubled the number of contributed posters.
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Aberson et al.
Contact (but little else) Predicts Implicit Attitudes toward African Americans
C. L. Aberson, S. C. Haag, C. Tomolillo, and C. Shoemaker
Department of Psychology; Humboldt State University
We proposed a model of intergroup contact wherein contact promotes understanding of outgroup perspectives, perspective taking reduces intergroup anxiety, reduced anxiety reduces stereotyping, and reduced stereotyping improves intergroup attitudes. We examined whether implicit attitudes followed this model or predictions afforded by an environmental association model. White undergraduates (n = 144) completed an implicit association measure and measures of contact, perspective taking, intergroup anxiety, stereotype endorsement, and explicit intergroup attitudes. Our model fit the data well but explained explicit attitudes better than implicit attitudes. Supporting an environmental association interpretation, contact was the only significant predictor of implicit attitudes. Findings support a dual-process model wherein implicit and explicit attitudes represent separate constructs and support the value of contact in improving intergroup attitudes.
Poster session presented at annual meeting of Society for Personality
and Social Psychology Conference, Austin, TX.
Absher et al.
Boulders Over Easy: Natural and Anthropogenic Disturbance in Patrick's Point State Park, Humboldt County, California
Matt Absher, Sean F. Craig, and Susan Swolfs
Department of Biological Sciences; Humboldt State University
Disturbance is a major factor that can regulate species richness and diversity in intertidal boulder fields. Wave action overturns boulders, potentially killing algae and invertebrates. Mortality can create free space, and new settlement may alter community structure. This study investigated the magnitude and impact of flipping of boulders by (1) waves and (2) humans on invertebrates and algae at Patrick's Point State Park, Humboldt County, CA.
To observe the effects of wave-induced flipping, the top and bottom of 36 mid-intertidal boulders were labeled in August 2001 and photographed monthly through March 2002. To estimate the frequency of wave-induced flipping, the position of boulders (bottom-up or bottom-down) was noted at each census. Results showed that genus richness declined linearly with increasing months spent bottom-up.
To estimate the magnitude of boulder flipping by humans, 143
students from 12 school groups were observed (10 minutes/student)
during class field trips in May and June 2002. Observations showed
that 32% of students flipped one or more boulders, but only 30%
of these "flippers" returned all boulders to their original
positions. Flipping activity depended upon a student's sex, age,
and school group affiliation. Since 664 students visited the study
site in May and June, an overly conservative estimate (assuming
10 minutes of activity per person) is that 372 boulders were overturned.
Data from an experiment that mimicked human flipping of boulders
showed that algal and invertebrate richness declined significantly
versus control boulders. Only algal richness recovered by the
following spring, when school groups returned.
Anderson
Theoretical/Conceptual
and Artistic Design of Interpretive Sign: "Thirsty and Hot
Desert Plants Strive to Survive."
Johanna Anderson
Department of Environmental and Natural Resource Sciences; Humboldt State University
This sign is categorized by what Sam Ham refers to as an "Outdoor
Exhibit," as well as a "Temporary Exhibit". The
primary purpose of both categories is "to educate an audience
by communicating a theme about a topic of interest; to orient
people to an area, or to focus their attention on particular features."
The subject of the sign is the adaptations desert plants have
made to survive, and the audience of the sign is overnight campers
and day hikers at Hole-in-the-Wall Campground, Mojave National
Preserve. If installed, the purpose of the sign is to inspire
visitors to look for the seasonal adaptations of desert plants;
to spark visitors' awareness of desert flora and desert seasonal
adaptations. This sign would be placed in an interp/info kiosk
near a campground along a popular route. In Mojave National Preserve
at Hole-in-Wall Campground, there would be a square interpretive
kiosk. This sign would be placed there along with three other
interpretive panels (one of each side of the square structure),
each 4 feet off the ground. This sign is perfectly readable from
2-6 feet, standard reading distance from a wall or bulletin board.
This sign should appeal to everyone who enjoys camping and the
desert, essentially everyone that will be in that vicinity. The
plants of the desert experience dramatic and noticeable seasonal
changes, and curious visitors will naturally wonder how plants
survive the dry and hot conditions. The tone of the voice is gentle
and guiding not telling and informational to promote
an atmosphere of wonder and curiosity.
Balliet
Perspective taking and Level of Action Construal
Daniel Balliet
Department of Psychology; Humboldt State University
Research that uses an empathy-inducing paradigm to test the
empathy-altruism hypothesis of altruistic motivation has been
criticized by recent researchers. Their argument is that the paradigm
used, perspective-taking, induces a conceptual merging of self
and other. Then the reason for helping cannot be due to a pure
altruistic motivation. The current study proposes that abstract
construal of action, a higher-level cognitive process involved
with self-other merging, is positively affected by the commonly
used empathy inducing perspective-taking condition. Recent work
demonstrates that higher levels of action construal is related
to a greater consideration for the goals of behavior, and consequently
causes greater perceptions of similarity, between the self and
both in-group and out-group members, because people are likely
to pursue similar goals. This hypothesis is tested in the context
of a prior method used to test the empathy-altruism hypothesis.
Seventy-six participants in three instruction conditions (perspective-taking,
objective, and abstract) were measured on a self-report emotional
reactivity scale (empathy, personal distress, and sadness) and
helping behavior, in response to a radio broadcast interview of
a college student in need. Using the Behavioral Identification
Form, participants' level of action construal (abstract to concrete)
was measured before and after the instruction condition. As hypothesized,
level of action construal is positively affected by the perspective-taking
instruction condition, compared to the objective condition. Results
are discussed in the context of prior research on the empathy-altruism
hypothesis, while encompassing the scientific debate of the existence
of an altruistic motivation.
Batista et al.
Thermal
Desorption Spectroscopy in Undergraduate Research
Fabian Batista, Ian T. Clark, Charles Heinberg, Yumiko Nakatsuka
and William G. Golden
Department of Chemistry, Humboldt State University, Arcata,
CA 95521
A thermal desorption spectrometer (TDS) is being constructed for
use in the undergraduate physical chemistry laboratory. The spectrometer,
coupled with a quadrupole mass spectrometer, will yield detailed
thermal desorption data for a variety of adsorption systems. These
TDS data will ultimately be acquired and analyzed by computer
utilizing data analysis software such as Mathematica®.
TDS is a standard surface analysis tool commonly used for studying
the behavior of adsorbed molecules on metal surfaces. It is interpreted
with relatively straightforward theory and yet provides a wealth
of knowledge about the nature of adsorbed surface species. In
an undergraduate physical chemistry laboratory environment the
technique will provide unique and practical experience in experimental
surface science. The test adsorption system being considered is
carbon monoxide adsorbed on a low area Pt(111) surface.
Batista et al.
The Effect of Different Acid Treatments on the Radiocarbon Age of Sedimentary Organic Matter
Fabian C. Batista,1 Ann P. McNichol,2 and Dana S. Gerlach2
1Department of Chemistry; Humboldt State University
and
2NOSAMS/WHOI; Woods Hole, Massachusetts
To date the bulk organic carbon in marine sediments it is necessary to first remove any inorganic carbon present by acidification. We tested three different acid treatments to see how the different methods affected the stable and radio-carbon isotopic values of the remaining organic matter. The standard NOSAMS method is to react the sediment with repeated aliquots of1.2N HCl until no visible dissolution reaction is present. The remaining sediment is then rinsed with distilled water. This method leaves a carbonate-free sediment that is easy to combust but suffers from the possible removal of acid-soluble organic matter. We compared this method to two methods that do not require rinsing of the sediments after acid treatment--a vapor phase acidification method using concentrated HCl (Hedges and Stern, 1984) and an in situ acidification with sulfurous acid (Verardo et al., 1990). Scaling these methods up to deal with the amount of sediment required for a radiocarbon date can present challenges that are not evident when dealing with the small quantities required for a percent organic carbon measurement. Vapor phase acidification of high carbonate sediments leaves hygroscopic salts that can impede sample combustion. Sulfurous acid is a weak acid and it is very difficult to determine when all the carbonate has been removed from a sediment sample. We tested sediments from 6 locations in (or near) the Atlantic Ocean that represented riverine, estuarine, and marine environments as well as a range of both organic and inorganic concentrations. We will present the isotopic results for these sediments and evaluate what is the most appropriate method to use.
Hedges J.I. and J.H. Stern (1984) Limnol. Oceanogr.
29, 657-663.
Verardo D.J., P.N. Froelich and A. McIntyre (1990) Deep-Sea
Res. 37, 157-165.
Conkey and Smith
Comparative Resistance of Woodrats (Genus Neotoma) to Venoms of Rattlesnakes (Genus Crotalus)
April T. Conkey1 and Steven A. Smith2
1Department of Wildlife and Fisheries; Texas A&M University and 2College of Natural Resources and Sciences; Humboldt State University
The gray woodrat (Neotoma micropus) has long been known to survive envenomation by the western diamondback rattlesnake (Crotalus atrox). Physiologically, its survival is at least partly due to the ability of N. micropus to neutralize hemorrhagic proteins found in rattlesnake venom. To determine the ubiquity of this phenomenon in woodrats, we used an antihemorrhagic assay to establish titers from sera of six species of woodrats against the venoms of nine rattlesnake taxa. Except for the venom of C. viridis helleri, antihemorrhagic titers were recorded for all species of woodrats (range 4-512). Among woodrats, N. micropus and N. albigula had the greatest ability to neutralize venom hemorrhagins, while N. cinerea and N. fuscipes exhibited the lowest antihemorrhagic titers.
Geographic distributions of the woodrats and rattlesnakes we
examined do not consistently support the expected relationship
between venom resistance and sympatry. As such, the adaptive significance
of the antihemorrhagic response is unclear.
Dengler et al.
Relative
Tsunami Hazard Maps, Humboldt County, California
Lori Dengler1, Brian Ludy2, and Jason Patton3
Departments of 1Geology, 2Geography,
and 3Environmental Systems;
Humboldt State University
We present a series of maps depicting the relative tsunami hazard of coastal Humboldt County in Northern California. Unlike inundation maps with a single line to show the inland extent of flooding, these maps use a four-color zonation scheme to represent relative risk. The highest hazard area has experienced tsunami or storm wave inundation in historic times. These areas include beaches and low coastal bluffs on the open coast and low areas adjacent to Humboldt Bay and major river deltas. The high hazard zones are also mapped as zone A (100 year flooding) or zone V (100 year flood with wave action) on FEMA Flood Insurance Rate Maps. Moderate hazard zones are areas likely to be flooded by a major tsunami generated by the Cascadia subduction zone based on published paleotsunami studies, numerical modeling (Bernard and others, 1994) and observations of recent tsunamis elsewhere. Current estimates of major Cascadia earthquake recurrence averages about 500 years. Low hazard zones show no evidence of flooding in the paleotsunami record and are likely to provide refuge in all but the most extreme event. No hazard areas are too high in elevation and/or too far inland to be at risk. A continuous gradational color scale ranging from red (high hazard) through orange (medium), yellow (low) to white (no hazard) depicts the zones. The blurred boundaries help convey the continuum of possible events and the uncertainty in delineating distinct inundation lines. The maps are GIS-based to facilitate ready adaptation by planners and emergency managers. The maps are intended for educational purposes, to improve awareness of tsunami hazards and to encourage emergency planning efforts of local and regional organizations by illustrating the range of possible tsunami events.
Presented at the American Geophysical Union Fall Meeting, December
2003.
Edinger-Marshall and Craig
Yellow Starthistle (Centaurea solstitialis) Production Decreases with Competition from Blue Wildrye (Elymus glaucus) Plugs, Six Rivers National Forest (NW California)
Susan B. Edinger-Marshall and Andrea M. Craig
Department of Rangeland Resources and Wildland Soils; Humboldt State University
Many publicly owned rangelands are remote, with agricultural techniques, such as cultivation or the use of herbicides, limited or prohibited. Our long-term objective is to restore a yellow starthistle (YST) (Centaurea solstitialis) infested site. Blue wildrye (EG) (Elymus glaucus) seed was gathered on the Six Rivers National Forest and sown in plugs. Questions addressed here include survival of grass plugs one year after transplantation, and the influence of plugs and/or weed whacking on YST stem counts, heights, seed heads, and seed heads per stem. In November 2002, 1,120 EG plugs were transplanted on 25 cm centers in a randomized block design, with or without a weed whacking treatment, performed in July 2002. Survival of grass plugs was evaluated in May and July 2003. YST data were collected in July and August 2003. Grass plug survival didn't differ significantly between weed whacked and non-weed whacked treatments, averaging 75% survival (May) and 42% after the onset of the dry season (July). In all but one of eight subplots, more than half of the surviving EG plugs produced seed. Final mortality figures were determined after the onset of the fall 2003 rainy season. YST stem counts per unit area didn't differ significantly between treatment and the control plots. Weed whacking stimulated YST stem heights, average heads per area, and average heads per stem. Plug-only treatments are the most promising technique for restoration at this site. Soil moisture studies may help determine whether grasses are competing with YST taproots at depth.
Presented in Salt Lake City, January 27, 2004 at the Annual
Meetings of the Society for Range Management.
Eschenbach and Cashman
Ethics in the Classroom: Engineering 111: Introduction to Design
Elizabeth Eschenbach and Eileen Cashman
Department of Environmental Resources Engineering; Humboldt State University
Armchair ethics can be easy for anybody. Traditional classroom conversations of professional ethics can be very distant from the day-to-day reality of university students. This classroom activity asks students to tie their own day-to-day ethical behavior to the ethical behavior of a practicing engineer.
Fryz-Boatwright et al.
Implicit Attitudes toward People with Disabilities
Joanna Fryz-Boatwright, Chris L. Aberson, and April M. Garcia
Department of Psychology; Humboldt State University
The primary goals of this study were to develop an implicit measure of attitudes towards people with disabilities (PWDs) and to establish the reliability and divergent validity of the measure. Several explicit measures of attitudes towards PWDs exist. However, explicit attitude measures may reflect expression of socially desirable beliefs rather than true attitudes towards PWD.
To address these measurement issues, we developed an implicit measure of attitudes towards people with disabilities. We modified the implicit association task (IAT, Greenwald, McGhee & Schwartz, 1998) to include reactions to pictures of physically disabled and non-disabled individuals. This IAT compares reaction times for stimuli that are compatible with negative attitudes (e.g., pairing of pictures of disabled person with negative words) and stimuli that are not compatible with negative attitudes (e.g., pairing of pictures of disabled person with positive words).
Sixty-two undergraduates completed the IAT and a two explicit attitude measures (Attitude Towards Disabled Persons Scale (ATDP) and Interaction with Disabled Persons Scale (IDP)). The implicit bias measure was reliable for both compatible (alpha = 0.93) and non-compatible stimuli (alpha = 0.93). Compatible task combinations were performed much faster than non-compatible combinations, t(61) = 10.9, p < 0.001, d = 0.91, indicating strong implicit biases against people with disabilities. Correlations between the IAT and explicit measures demonstrated divergent validity. The IAT was weakly related to both the ATDP scale, r(61) = 0.15, p = 0.10 and the IDP scale, r(58) = -0.18, p = 0.05. Scores on both explicit measures were low, indicating that the explicit attitude measures did not reflect negative reactions to PWD.
The most noteworthy results of the current study were that
participants exhibited strong implicit biases against people with
physical disabilities and that implicit biases were relatively
independent of explicit attitudes. Thus, the implicit measure
demonstrated biases among participants who explicitly disavowed
prejudice. These findings are encouraging regarding the usefulness
implicit measures but are discouraging regarding reactions to
PWD.
Furuoka et al.
Teachers' Views
on Including Children with Autism in General Education Settings
Jill H. Furuoka, Mary B. Gruber, and Carrie Moses Roth
Department of Psychology; Humboldt State University
An important goal of behavior analysts working with special-needs children is to facilitate their inclusion into general education settings. This study investigated factors relating to teachers' willingness to include children with autism in their classrooms. This study surveyed 93 elementary school teachers, including 74 regular education teachers and 19 special education teachers. The survey included questions on their training and experience with children with autism and on their willingness to include children with autism in their classes. The survey also included the Personal Teaching Efficacy Scale (Gibson & Dembo, 1984), which had 9 items about teaching efficacy to be rated on a 6-point scale from "Strongly Disagree" to "Strongly Agree". The survey also included the Adaptation Evaluation Instrument (Schumm & Vaughn, 1991), which had 20 items about teaching adaptations to be rated on a 6-point scale from "Highly Unfeasible" to "Highly Feasible".
Factor analysis of the Teaching Efficacy Scale yielded two separate factors, reflecting teachers' perception of their Efficacy for Facilitating Student Success and their Efficacy for Handling Student Difficulties. Factor analysis of the Adaptation Evaluation Instrument yielded three separate factors, reflecting teachers' perceived feasibility of making Class Format, Relationship, and Involvement Adaptations for special-needs students.
The special education teachers scored significantly higher than regular education teachers on their autism instruction hours (t(88) = 2.90, p < 0.01), autism work experience (t(91) = 2.27, p < 0.01), willingness to include students with autism (t(82) = 3.14, p< 0.01), and perceived feasibility of making Class Format Adaptations (t(91 )= 2.02, p < 0.05). Regular and special education teachers scored similarly to each other, however, on the other measures, including their perceived Efficacy for Facilitating Student Success, Efficacy for Handling Student Difficulties, Feasibility of Relationship Adaptations, and Feasibility of Involvement Adaptations.
Significant predictors of the regular education teachers' willingness to include children with autism, shown in stepwise multiple regression analysis, were their perceived Efficacy for Handling Student Difficulties (beta = 0.296, p < 0.01), perceived Feasibility of Involvement Adaptations (beta= 0.296, p < 0.01), being more willing with an aide (beta = 0.280, p < 0.01), and valuing of more training on autism (beta = 0.270, p < 0.01). Written comments by teachers shared ideas of other factors that contributed to their feelings about inclusion. The most commonly mentioned factors were time constraints, pressure to meet state standards for student test scores, and the need for additional aides with training in autism.
These findings support the importance of the behavior analyst's role in facilitating successful inclusion of children with autism. Behavior analysts can address the key factors relating to teachers' willingness to include children with autism in several ways. These ways include giving training to teachers on autism, providing trained aides who can give skilled behavioral support in the classroom, teaching specific strategies that will raise teachers' efficacy for handling student difficulties, and helping teachers make adaptations that successfully involve students with autism in class activities.
Presented at the Association for Behavior Analysis Annual Convention,
May 24, 2003, San Francisco.
Gold
Predicting the Intentions and Behavior of Others: Factors Affecting Accuracy
Gregg J. Gold
Department of Psychology; Humboldt State University
Making accurate predictions about others' intentions and behavior is important to successful social interaction. Here, the efficacy of different predictive strategies and their potential mechanisms were examined.
In three studies, participants were assigned to one of three conditions: Making predictions about their own behaviors (criterions); role-playing criterions and making predictions (role); or simply making predictions concerning criterions (non-role). In Study 1, predictions concerned potential influence strategies. In Study 2, predictions concerned which personality traits a stereotyped group would endorse. In Study 3, predictions concerned a project planner's estimated starting and finishing times.
Role-playing was hypothesized to allow the adoption of the cognitive mindset of targets and reduce stereotype use. This could allow for increased accuracy. Similar effects were not expected for non-role players.
In Study 1, as expected, role-player's predictions were closer to criterions than non-role players predictions. Non-role players overestimated potential use of stereotypically harsh influence strategies.
In Study 2, role-players were accurate making predictions regarding positive traits, but not concerning negative traits. For non-role players, results were reversed.
In Study 3, role-players erred consistent with a mindset specific to planners, while non-role players did not.
Overall results suggest role-playing can enhance or detract from predictive accuracy according to how accurate criterion subjects are in predicting their own behaviors. Equally important, two mechanisms were implicated in these effects for role-players: A reduced use of stereotypes, and adoption of the target's mindset.
Golden and Zoellner
A Computational Examination of Perfluoroalkane Conformations and Implications for the Adsorption of Perfluoroalkanes on Platinum(111) Surfaces
William G. Golden and Robert W. Zoellner
Department of Chemistry, Humboldt State University
The two lowest-energy conformers of perfluorohexane and perfluoroheptane
were investigated at the Hartree-Fock RHF/6-31G* level and the
structures, properties, and vibrational frequencies determined.
The lowest energy conformers of perfluorohexane were found to
differ by 8.600 kJ/mol (2.055 kcal/mol) at this level of theory,
while the lowest energy conformers of perfluoroheptane differed
by 8.662 kJ/mol (2.070 kcal/mol). In addition, the transition
state for the interconversion between the two lowest-energy conformers
of perfluorohexane was investigated at the RHF/6-31G* level, and
was found to lie 13.247 kJ/mol (3.166 kcal/mol) above the energy
of the lowest-energy conformer, while the transition state for
the equivalent interconversion between the perfluoroheptane conformers
was 15.279 kJ/mol (3.652 kcal/mol) above the energy of the lowest
energy conformer. These results have been used to interpret previously
published thermal desorption and infrared reflection-absorption
spectroscopic data for the monolayer and sub-monolayer adsorption
of perfluorocarbon molecules on a single-crystal Pt(111) surface
under ultra-high vacuum conditions.
Haddad et al.
Dendritic Flux Jumps in a Bulk Superconducting Crystal
R. Haddad,1 M. M. Mola,1 and S. Hill2
1Department of Physics and Physical Science; Humboldt State University and 2Department of Physics; University of Florida
Angle dependant torque magnetization measurements have been
carried out on the organic superconductor, k-(ET)2Cu(NCS)2 at
extremely low temperatures (25 300 mK). Magneto-thermal
instabilities are observed in the form of abrupt magnetization
(flux) jumps for magnetic field sweeps of 0 20 Tesla. A
fractal analysis of the flux jumps indicate that the instabilities
do show a self-similar structure with a fractal dimension of varying
between 1.2 1.4. The fractal structure of the flux jumps
in our sample shows a striking similarity to that of MgB2 thin
film samples, in which magneto-optical experiments have recently
shown that the small flux jumps are due to the formation of dendritic
flux structures. These smaller instabilities act to suppress the
critical current density of the thin films. The similarity of
the flux jump structure of our samples suggests that we are also
observing the dendritic instability, but in a bulk sample rather
than a thin film. This is the first observation of the dendritic
instability in a bulk superconducting sample, and is likely due
to the layered nature of k-(ET)2Cu(NCS)2, which results in a quasi-two
dimensional flux structure over the majority it's mixed state
phase diagram.
Hamm and Zoellner
A Novel Di-Zwitterionic Boron-Substituted Analog of a Simple Amino Acid
Luke S. Hamm and Robert W. Zoellner
Department of Chemistry; Humboldt State University
Boron substitution at the alpha-carbon position of glycine,
a simple amino acid, along with the substitution of a positively-charged
amine R-group in place of one of the glycine hydrogen atoms, yields
a di-zwitterionic amino acid analog. Herein is reported the examination
of a series of di-zwitterionic boron-substituted analogs of glycine
using computational methods (specifically the Hartree-Fock 3-21G(*)
level of theory). Species bearing unsubstituted ammonium groups
had a tendency to be destabilized by the nearby carboxylate group.
Highly methyl-substituted species were more stable than systems
without methyl-substitution.
Hemphill-Haley and Humphreys
Integration of Geologic and Geodetic Data into Kinematic Models of Contemporary Strain in the Pacific Northwest and Across the Cascadia Subduction Zone
Mark A. Hemphill-Haley1 and Eugene D. Humphreys2
1Department of Geology; Humboldt State University and 2Department of Geological Sciences; University of Oregon
Penetrative dextral shear combined with gravitational collapse-driven extension provide complex but coherent patterns of deformation within the interior of the western United States. We model geologic, neotectonic and GPS geodetic data to infer the western North America velocity and deformation field. Geodetic observations indicate 9-12 mm/y of margin-parallel shear (with respect to stable North America) is located east of the Sierra Nevada and 3-5 mm/y of west- to northwest-directed extension occurs in the central Basin and Range.
Our goal has been to resolve the horizontal velocity field and strain rate tensor within western North America and specifically in the Pacific Northwest. We use finite element modeling of deformation to incorporate available neotectonic and geodetic data. A finite element mesh defines the elements in which material properties are assigned, with properties chosen to produce desired deformation behavior. For instance, blocks are made rigid and deformation zones are weak. Block motion is then prescribed, and the resulting velocity field is compared to GPS velocities. The deformation field is then compared to geologic strain indicators. We adjust material strength and applied velocities in an attempt to eliminate conflicts between the modeled and observed fields. This modeling, though done with finite elements, is kinematic in nature. That is, we use finite element modeling to produce velocity and strain fields that are consistent with observations. We do not attempt to model the actual forces or rheologies active in the Earth. Finite elements are a means of producing relatively smooth fields (in this kinematic modeling, the modeled velocity field can be viewed as the weighted least squares best velocity field consistent with the prescribed velocities).a
To summarize the results of our modeling, broadly distributed strain occurs throughout the region with transform rates being much greater and largely concentrated near margin while gravitational collapse drives extension and deformation of the interior. The Oregon Coast Range block is rotating rapidly clockwise with a pole of rotation in south-central Washington consistent with a model proposed by Wells et al.b This accommodates both the northern motion of the Coast Ranges into the Olympic Mountains and Basin and Range extension in such a way that North America strain rate diminishes to the north and is very slight in Canada. It also increases subduction velocities, especially in Oregon. Eastern California shear zone strain "fans" broadly over the Pacific Northwest with several mm/yr of strain rate occurring in the Klamath Mountain region. This unexpected result finds support directly in the GPS velocity field; comparison of the velocity of a station at Quincy with that of Yreka shows a transfer of Eastern California shear zone strain to the northern California coast, reducing the strain required in Oregon and Washington.
The results also indicate that our current modeling is inadequate in some regards, and is substantially unconstrained throughout much of the Pacific Northwest. In particular, a prevalence of strike-slip deformation in the Great Basin results from a N-S contraction field that is too great. This problem may simply result from moving station DRAO (Pentictin) in Canada at about 1 mm/y to the northeast instead of 2-3 mm/yr consistent with recent observations. This slower velocity may prevent northeast Washington and northern Idaho from "getting out of the way" of the northwest-directed Basin and Range extension.
An additional result of our kinematic modeling is the determination of subduction velocity, requiring knowledge of the Coast Ranges and Juan de Fuca velocities. Older estimates used NUVEL-derived Juan de Fuca-North America velocities. The Coast Range is in motion relative to North America and relative to the subduction zone. Juan de Fuca velocity estimates have uncertainties related to dependency on the Pacific plate velocity which is being refined, and appears to be several mm/yr more westerly than previously assumed,c which reduces subduction velocities.
Finally, the Cascadia subduction zone serves as the outlet (window) for both transform and gravitational collapse driven deformation and the expansion of North America. Conversely, the transform margin prevents collapse from being accommodated in California. The result, over time, is that the expansion of the western U.S. has been redirected toward the Pacific Northwest as the transform margin has expanded and the length of the subduction zone has decreased.
aHearn, E.H., and Humphreys, E.D., 1998, Kinematics of the southern Walker Lane Belt and motion of the Sierra Nevada block, California: Journal of Geophysical Research, v. 103, p. 27,033-27,049.
bWells, R.E., Weaver, C.S., and Blakely, R.J., 1998, Fore-arc migration in Cascadia and its neotectonic significance: Geology, v. 26, p. 759-762.
cAntonelis, K., Johnson, D.J., Miller,
M.M., and Palmer, R., 1999, GPS determination of current Pacific-North
American plate motion: Geology, v. 27, p. 299-302; DeMets, C.,
and Dixon, T.H., 1999, New kinematic models for Pacific North
America motion from 3 Ma to present: Evidence for steady motion
and biases in the NUVEL-1A model: Geophysical Research Letters,
v. 26, p. 1921-1924; Humphreys, E.D., and Weldon, R.J., II, 1994,
Deformation across the western United States: A local estimate
of Pacific-North America transform deformation: Journal of Geophysical
Research, v. 99, p. 19,975-20,010.
.
Howe
The ACT (Adults and Children Together) Violence Prevention Program in Humboldt County
Tasha R. Howe
Department of Psychology; Humboldt State University
The ACT (Adults and Children Together) violence prevention program is an empirically based program with four main components: Anger management, nonviolent problem solving, positive parenting, and media literacy. Each module is based on current psychological research. The program is a "train the trainers" model. National training takes place at the American Psychological Association headquarters in Washington D.C. After becoming a nationally trained trainer, I will be the designated ACT trainer for Humboldt County. I have collected preliminary data on violence prevention efforts in the county and have held information-gathering meetings to assess the need for this type of program. Representatives from various social service agencies, childcare organizations, and family violence centers have expressed great interest in this program. ACT is unique in that it targets adults who work with families who have children between the ages of 0-8 years. Research shows these early years are crucial for the development of fairly stable information processing patterns, emotional response styles, and tendencies toward violence and aggression. The poster will outline the ACT program and show the organizational structure of how it will be implemented in Humboldt County. It will also illustrate how data will be collected to evaluate the implementation and effectiveness of the program.
Hu
Viewing Emotion-Inducing Photographs Produces Specific Patterns of Facial EMG Activities
Senqi Hu
Department of Psychology; Humboldt State University
The purpose of the present study was to investigate the effects
of viewing emotion-inducing photographs on the responses of facial
EMG activity. Forty subjects participated in the experiment. Half
of the subjects first viewed a series of photographs with fearful
scenes and then viewed a series of photographs with peaceful scenes.
The other half of the subjects first viewed a series of photographs
with peaceful scenes and then viewed a series of photographs with
fearful scenes. Subjects' facial electromyographic (EMG) activities
at the frontalis and zygomaticus regions were recorded while they
were viewing emotion-inducing photographs. The results showed
that viewing emotion-inducing photographs produces specific patterns
of facial EMG activities. The means for the ratio of EMG spectral
power between the viewing photographs and baseline periods were
2.27 at the left frontalis region, 1.84 at the right frontalis
region, 1.44 at the left zygomaticus region, and 1.16 at the right
zygomaticus region while viewing photographs with fearful scenes.
The means for the ratio of EMG spectral power between the viewing
photographs and baseline periods were 1.22 at the left frontalis
region, 0.97 at the right frontalis region, 1.48 at the left zygomaticus
region, and 1.24 at the right zygomaticus region while viewing
photographs with peaceful scenes. Further statistical analysis
indicated that the EMG activities at the frontalis region generated
significantly higher power than those at the zygomaticus region
while viewing photographs with fearful scenes (p < 0.01). The
EMG activities at the zygomaticus region generated significantly
higher power than those at the frontalis region while viewing
photographs with peaceful scenes (p < 0.01). It was concluded
that viewing negative emotion-inducing photographs was associated
with increased EMG activities at frontalis muscles and that viewing
positive emotion-inducing photographs was associated with increased
EMG activities at zygomatic muscles.
Johnston and Schwab
Trace Element Equilibration during Laboratory Melting of the Mantle: Diffusion versus Dissolution/Reprecipitation
A. Dana Johnston1 and Brandon E. Schwab2
1Department of Geological Sciences; University of Oregon; and 2Department of Geology; Humboldt State University
Ion probe measurements of the abundances of selected REE, Ti, Cr, Rb, Sr, Y, Zr, and Nb, have been collected from the glass (quenched melt) in 32 run products from piston-cylinder experiments at 1.0 GPa. Starting materials consisted of five lherzolitic to wehrlitic mixtures of natural ol, cpx, opx, and sp handpicked from fresh xenoliths; these were analyzed for their initial trace element inventories, C(o), by ICP-MS. Graphite-lined Pt capsules were used and the melt was separated from the residual minerals into a layer of vitreous carbon spheres thus circumventing Fe-loss and quench modification of the melt. Least-squares inversion of the major element compositions of all phases in each run product yielded modes.
Using the calculated modes in conjunction with published mineral/melt
k's, we calculated bulk distribution coefficients for each experiment.
With these and the measured C(o) values, the calculated melt fractions,
and the batch melting equation, we calculated the trace element
concentrations that would be expected in the melts if equilibrium
were achieved. These values generally agree with the measurements
to within the error on the ion probe measurements, and linear
fits to plots of the calculated versus measured data yield slopes
close to 1.0 and r2 values exceeding 0.90. From this we
conclude that equilibrium with respect to trace element distribution
was closely approached in our experiments, a conclusion that at
first seems at odds with recently measured REE diffusivities in
diopside. These data suggest diffusion coefficients for La of
10-2010-19 m2/s (depending on T) with Yb D's about 10 times
larger. Approximating diffusion length scales by [square root(Dt)]
and applying these to spherical grains with diameters of 10 microns
(to model our starting materials) leads to the expectation that
little of our starting cpx should have equilibrated, if diffusion
was the controlling process. However, the textures of our run
products reveal that the post-run grain sizes are much larger
(~2-10_) than in our starting materials suggesting that dissolution
of small grains with concomitant reprecipitation to produce larger
grains is an important process in experiments like these. If correct,
trace elements would be released to the melt as dissolution occurs
and reincorporated in minerals as reprecipitation occurs, but
as this latter process represents growth from melt in which diffusion
is much faster than in solids, equilibrium would be expected to
be more closely approached than by diffusion in solids alone,
as we have observed.
Katz
et al.
Riparian Flora Observed at Riparian Revegetation
Projects in North Coastal
California
R. Katz,1 M. Lennox,1 D. Lewis,2 R. Jackson,2; J. Harper,1 B. Allen-Diaz,3 S. Larson,1 and K. Tate4
1University of California Cooperative Extension; Santa Rosa, California; 2University of Wisconsin; Madison, Wisconsin; 3University of California; Berkeley, California; and 4University of California; Davis, California
The flora observed at revegetation sites is a management concern for many landowners and agency efforts involved in analyzing stream function, riparian restoration, native plant conservation, and natural resource management in California. There is the potential for competition from non-native species to displace individuals and populations of native riparian species. We have conducted a cross-sectional survey of 70 existing riparian revegetation projects in Marin, Sonoma and Mendocino Counties to document the resulting composition of flora. The project is a collaborative effort between the University of California Cooperative Extension, resource agencies, consultants, private landowners, and watershed groups, working in coastal California. Sites ranged from 4 to 39 years in project age and received treatments of exclusionary fencing and active planting or fencing alone. The poster will report and compare the presence of native and non-native plant species. In addition, we will share observations of species succession, as well as plot measurements of dominant species cover. This documentation is the first step in using the project database to inform effective design, installation, and maintenance of riparian revegetation projects.
Presented at the Redwood Symposium and Salmonoid Restoration
Federation Conferences.
Kinziger
Evidence Supporting Two New Forms and One Previously-Described Race within the Cottus carolinae Species-Complex from the Ozark Highlands
Andrew P. Kinziger
Department of Fisheries Biology; Humboldt State University
I present preliminary data describing two new forms within
the Cottus carolinae species-complex from the Ozark Highlands:
The eyelash sculpin and the fringe-head sculpin. The eyelash and
fringe-head sculpins can be diagnosed from all other species of
Cottus by cirri (thin fleshy appendages), a character heretofore
unknown in the genus. The eyelash sculpin can be further diagnosed
by a few cirri above the eye and the fringe-head sculpin by a
large number of cirri on the head and elsewhere. In addition I
provide data on pectoral fin ray number in the C. carolinae
species-complex that validates the recognition of the Black River
race in the Ozark Highlands (18-19 in Black River race, 13-17
in all other C. carolinae). The distribution of Ozark Highland
members of the C. carolinae species-complex and a new size
record are also discussed.
Lenahan et al.
ERP's Associated with Successful EMG Biofeedback and Three Feedback Modes
John Lenahan, Kevin Cheli Colando, and John M. Morgan
Department of Psychology; Humboldt State University
Research Question: What is the relationship between brain activity (as measured by the event-related potential (ERP) [computer-averaged electroencephalogram]) preceding successful attempts at relaxation in an electromyogram (EMG) biofeedback relaxation program across sessions? We wanted to observe the cascade of brain activity that precedes successful relaxation during training.
Procedure: Eight Psychology undergraduates served as participants, each returning for 8 sessions of training involving EMG Biofeedback, relaxation training involving progressive relaxation exercises. During each session the participants experienced 2 fifteen minute blocks in which the three feedback conditions were randomly ordered and each was operational for five minutes. Each participant was fitted with active EEG electrodes at F3, Fz, F4, C3, Cz, C4, P3, Pz, P4 referred to linked ear lobes. Vertical and horizontal eye movements were also recorded. Also active EMG electrodes were placed over each eye with the ground centered and equidistant so that EMG could be recorded simultaneously with the EEG.
Definitions: Feedback Conditions: (1) Continuous-The feedback tone increased in frequency as the EMG increased and decreased as the EMG decreased. (2) Threshold Silences Feedback-The additional circuitry automatically adjusted the threshold setting of the continuous, audio feedback and when the EMG decreased below the threshold, the continuous feedback was silenced. (3) Baseline-There was no audio feedback during condition. "Success" is defined as the decrease of the Frontalis muscle EMG that remained below the threshold setting for at least 2 seconds.
Results: I. Relaxation response accelerated as sessions proceeded; II. Feedback condition 2 (the auditory feedback changed into silence for the time that the EMG remained below a previously set criterion 'threshold') was the most efficient training method as measured by: (1) the increased frequency of "Success" in session 2, (2) the subsequent decrease in the frequency of "Success" along with the increase in the duration that the EMG remained below the threshold, (3) the shortening of the latency between threshold crossings, and (4) the increased rate of relaxation episodes, resulting in a statistically and behaviorally significant decrease in the EMG; III. The decrease in the EMG was correlated (r = 0.78) with the increase in the participants' subjective report of relaxation; IV. Negative ERP waves increased in amplitude over the right and central portions of the frontal, central and parietal scalp areas as the EMG decreased and subjective reports of relaxation increased; V. Condition 2 showed the largest amplitude negative waves of the three conditions; VI. Increase in negative waves is generally interpreted as an increase in brain excitatory activity, in this case leading to faster and more complete learning of the relaxation response.
Interpretations: Condition 2 is the most efficient method of Frontalis EMG Biofeedback relaxation training. An increase in excitatory brain activity in the right and central frontal, central, & parietal cortexes precedes the occurrence of successful, voluntary decreases in Frontalis muscle activity and a corresponding increase in subjective reports of relaxation.
Lincoln
and Smith
An Alternate Pathway to Cyclobutadienetricarbonyliron(0)
Matthew Lincoln and Joshua R. Smith
Department of Chemistry; Humboldt State University
Cyclobutadienetricarbonyliron(0) has been synthesized via many pathways. The "standard" Organic Synthesis method is reliable, but requires extreme reaction conditions and cycloctatetraene, which is expensive (~$40/gram). The intention is to design a reaction scheme appropriate for undergraduate research: mild conditions, inexpensive starting materials and appreciable yields. The proposed scheme is initiated by a photo [2+2] dimerization of crystalline maleic anhydride with itself.
Madej et al.
Using Dynamic Programming and Genetic Algorithms to Reduce Erosion Risks From Forest Roads
M. A. Madej,1 E. A. Eschenbach,2 R. L. Teasley,2 C. A. Diaz,2 and J. Simi,2 and J. Wartella3
1United States Geological Survey; 2Department of Environmental Resources Engineering; Humboldt State University; and 3Redwood National and State Parks
Many anadromous fisheries streams in the Pacific Northwest have been damaged by various land use activities, including timber harvest and road construction. Unpaved forest roads can cause erosion and downstream sedimentation damage in anadromous fish-bearing streams. Although road decommissioning and road upgrading activities have been conducted on many of these roads, these activities have usually been implemented and evaluated on a site-specific basis without the benefit of a watershed perspective. Land managers still struggle with designing the most effective road treatment plan to minimize erosion while keeping costs reasonable across a large land base. Trade-offs between costs of different levels of treatment and the net effect on reducing sediment risks to streams need to be quantified. For example, which problems should be treated first, and by what treatment method? Is it better to fix one large problem or 100 small problems? If sediment reduction to anadromous fish-bearing streams is the desired outcome of road treatment activities, more rigorous evaluation of risks and optimization of treatments are needed. Two approaches, Dynamic Programming (DP) and Genetic Algorithms (GA), were successfully used to determine the most effective treatment levels for roads and stream crossings in a pilot study basin with approximately 200 road segments and stream crossings and in an actual watershed with approximately 600 road segments and crossings. The optimization models determine the treatment levels for roads and crossings that maximize the total sediment saved within a watershed while maintaining the total treatment cost within the specified budget. The optimization models import GIS data on roads and crossings and export the optimal treatment level for each road and crossing to the GIS watershed model.
Martin and Harris
Are Bear-proof Food Storage Canisters being used effectively on the Lost Coast Trail?
Steven R. Martin and Emily J. Harris
Department of Environmental and Natural Resource Sciences; Humboldt State University
Introduction. The King Range National Conservation Area, managed by the Bureau of Land Management (BLM), stretches for 35 miles along the northern coast of California. The popular Lost Coast Trail (LCT) hugs this rugged and dramatic coastline, attracting thousands of day-hikers and backpackers each summer. As overnight recreational use of the LCT has increased, so have encounters with black bears entering campsites in search of food. As one part of a larger visitor study, we investigated (1) the extent to which overnight visitors used bear-proof food storage canisters; (2) why visitors did not use a canister; (3) how frequently bears visited campsites and how frequently bears obtained food; (4) whether visitors supported the required use of bear-proof food storage canisters; and (5) whether visitors supported the installation of bear-proof food storage lockers along the LCT. We also examined some group and trip characteristics associated with the variables listed above.
Methods. A graduate student contacted LCT users on a stratified random sampling basis from May 24 to August 12, 2003. Contacted visitors were asked to provide a name and address where a detailed questionnaire was mailed to them after their trip. Up to four individuals per group were asked to participate. A reminder postcard, and, if necessary, a follow-up questionnaire, was mailed to each participant. We collected 393 useable names and addresses. Of the 283 completed surveys received (a 72% response rate), 199 were from overnight campers, which comprises the sample for this analysis.
Results. Nearly 84% of overnight visitors reported using
bear-proof food storage canisters. Of these, 70% rented the canister(s),
27% owned the canister(s), and 3% both owned and rented canisters.
Eighteen visitors (9% of our sample) said they did not know they
were required to use a bear-proof canister; this was also the
most common reason given for not using one (13 visitors), followed
by not having/owning one (5), not wanting to carry the extra weight
(3), and canisters being too expensive (3). Nine percent (9%)
of our sample also incorrectly identified hanging as a correct
method of food storage along the LCT. Fourteen groups reported
that a bear visited their campsite; 13 of those groups used a
canister. Nevertheless, 3 groups using a canister reported that
a bear still obtained food. These visitors indicated that despite
using a canister, some food was inadvertently left out of the
canister, or there was too much food and/or trash to fit into
the canister. Although only 26% of visitors reported reading the
Leave No Trace Outdoor Skills and Ethics pamphlet provided by
the BLM, visitors who did read it were more likely than expected
to use a canister than those who did not read it (chi-square =
6.3). First-time visitors to the LCT were also more likely than
expected to use a canister than were return visitors (chi-square
= 17.7). Primary information source used by visitors in trip planning
influenced their use of canisters (chi-square = 39.4). All 37
visitors who reported the BLM as their primary source of trip
planning information used a canister; those who reported friends
or relatives as their primary information source were less likely
than expected to use a canister. Miles traveled to visit the LCT
also influenced use of canisters (chi-square = 58.8); visitors
living within 100 miles of the LCT were less likely than expected
to use a canister, while those living more than 100 miles away
were more likely to use a canister. Support for the required use
of canisters was strong-85% of visitors indicated they would somewhat
(20.5%) or strongly (64.5%) support the required use of canisters.
Support for the installation of bear-proof food storage lockers
at popular backcountry campsites was mixed: 49% of visitors were
in favor, 32% were opposed, and 19% were neutral.
Martin et al.
Effect of 70 Years of Recreational Car Camping on Vigor of Old Growth Coast Redwood and Douglas-fir
Steven R. Martin,1 John D. Stuart,2 Portia Halbert,3 and Mark A. Rizzardi4
1Departmant of Environmental and Natural Resource Sciences; 2Department of Forestry and Watershed Management; and 4Department of Mathematics; Humboldt State University; and 3Big Basin Redwoods State Park; Santa Cruz, California
Introduction. Recreationists have been car camping at Blooms Creek campground in Big Basin Redwoods state park annually for 70 years. Park managers are interested in better understanding the effects that such long-term recreational use may have on the health and vigor of the forest overstory.
The Problem. Trampling and vehicle use are major causes of impacts to wildland recreation area soils, including soil compaction, increased soil density and runoff and erosion, reduced macroporosity and aeration, infiltration rates, and litter and humus layers, changes in soil structure and stability, in soil temperature regimes, and in soil chemistry and available nutrients, and a reduction in soil microorganisms; these impacts are assumed to adversely affect plant vigor. Concern over the effects of long-term recreational trampling on the vigor of mature redwoods has existed since the early days of the redwood state parks, but the few investigations into those perceived impacts have been inconclusive. This investigation seeks to directly, quantitatively measure the vigor of mature redwoods and Douglas-fir in a campground that has withstood many years of recreational use.
Methods. The study was conducted in Big Basin Redwoods State Park. Study sites were located in the Blooms Creek campground and along the relatively untrammeled Opal Creek. The Blooms Creek campground was opened in the 1930s and consists of 48 drive-in and 4 walk-in campsites. Opal Creek has a narrow, lightly used trail running through it with no evidence of off-trail use, and served as the control site. Study sites were located in alluvial redwood forests with Douglas-fir as the dominant or co-dominant species. In each of the two study sites, all of the redwood and Douglas-fir trees that were emergent or dominant crown class were sampled. This resulted in sample sizes of 35 redwood and 22 Douglas-fir trees sampled in the campground, and 19 redwood and 12 Douglas-fir trees in the control site. For each sampled tree we measured height and crown length, circumference, and sapwood and bark thickness. We used these measurements to calculate live crown percent, diameter, radius inside the bark, total basal area at breast height, and heartwood and sapwood basal area. We then calculated crown length to sapwood basal area (CL/SBA) as an index measure of crown density, our chosen indicator of tree vigor.
Results. A Mann-Whitney test for equality of medians was performed to compare redwoods and Douglas-firs in the campground and control sites. For redwoods, there was no significant difference (_ = .05) in height, diameter, crown length, live crown percent, sapwood basal area, or the CL/SBA index measure between the campground and control study sites. For Douglas-fir, the only significant differences between the campground and control sites were for length of live crown and live crown percent, with Douglas-firs in the control site possessing a longer live crown and a larger live crown percent; there was no significant difference for crown density. To further test for a campground effect controlling for tree height and diameter, separate linear regression models were constructed for each tree species. There was no statistically significant campground effect for the redwoods (P=0.79) and Douglas-firs (P=0.94) after controlling for tree height and diameter. (Model: ).
Conclusions. Despite intuitive concerns expressed by
academics and resource managers regarding the detrimental effects
of recreational trampling on the health and vigor of mature trees
in recreational areas, our study of coast redwoods and Douglas-firs
in a California state park recreational campground used annually
for more than 70 years found no significant difference in crown
density between overstory redwoods and Douglas-firs in the campground
with those in an untrampled control plot.
McLaughlin and Zoellner
The Identification of the Smallest Stable Alkane Trefoil Knot
Stephanie E. McLaughlin and Robert W. Zoellner
Department of Chemistry; Humboldt State University
Various sized cyclic alkanes each containing a single trefoil knot were constructed and investigated using the PC Spartan Pro molecular modeling software package. The PM3 semi-empirical method was first used to determine the feasible size range in which stable alkane knots could possibly exist. Following this determination, the RHF/3-21G(*) ab initio Hartree-Fock method was then used to determine energy minima, structures, and properties of these alkane knots. The alkane knot containing 27 carbon atoms (C27H54) was found to be the smallest stable alkane knot; smaller knots either were determined to have imaginary infrared vibrational frequencies or unreasonably long carbon-carbon bonds.
McVean et al.
Contact, Anxiety, and Perspective Taking Predict Attitudes towards the Homeless
A. D. McVean, C. L. Aberson, P. Young
Department of Psychology; Humboldt State University
This study examines contact, anxiety, and perspective taking as predictors of attitudes towards the homeless. Participants completed an internet-based questionnaire that included items assessing opportunity of contact with the homeless, quality (i.e., Allport's conditions), quantity, and salience (i.e., viewing contact as typical of the homeless), measures of intergroup anxiety and ability to understand homeless people's perspective, and an attitude towards the homeless measure. Using these variables, we proposed a model predicting attitudes towards the homeless from the contact, anxiety, and perspective taking measures.
Three hundred and sixty-six participants completed the questionnaire.
The Internet sample consisted of 74% whites, 5% African-Americans,
9% Hispanics, 3% Asians, and 9% other ethnicities with 39% of
the sample being men. Fifty-six percent of the participants were
not college students. Analyses produced a path model that did
not fit the data well, robust CFI = 0.93, chi-square = 107.22,
p < 0.001, RMSEA = 0.20, but did reveal several significant
relationships. Attitude towards the homeless was best predicted
by quality of contact with the homeless and the ability to understand
homeless people's perspective. Salience of contact and quantity
of contact were good predictors of perspective taking, possibly
showing that more contact with typical group members increases
one's willingness to empathize with homeless people in general.
Greater amounts of contact reduced levels of intergroup anxiety,
as did contact with individuals that were seen to be typical homeless
people. Salience and quantity of contact were also good predictors
of anxiety, with higher levels of both seeming to reduce anxiety.
Results highlight the mediating effects of perspective taking
on attitudes towards the homeless, and the importance of quality
of contact in predicting attitudes towards the homeless. Additionally,
results suggest that predictions derived from research on interethnic
attitudes may not be appropriate for predicting attitudes toward
the homeless.
Mitchell
What is that Black Stuff? Composition and Depositional Processes of Megaphytoclasts in the Yager Terrain of Northern California
Martha Mitchell
Department of Geology; Humboldt State University
Although the occurrence of transported plant fragments within
the Franciscan Complex and more specifically the Yager terrain
turbidites have been documented in stratigraphic sequences, further
study of these phytoclasts is limited. While recently conducting
a quarry site
inspection, I noticed unusual black inclusions in a fractured
coarse sandstone boulder. The clasts appeared to be the remains
of woody debris. The initial purpose of the investigation was
to determine if the clasts were indeed the remains of woody debris
and if so attempt to identify possible environments of deposition.
Miller discusses hydrofoil stripping as a possible model for the
accumulation of such phytoclasts in sandy turbidites. In this
model, the phytoclasts are wafted forward and upward in the head
region of the debris flow. Concentrations may be buried by finer
grained shale or may accumulate without further clastic deposition
as evidenced by deep-sea terrigeneous coal laminae (Miller 1995).
Momb and Schineller
Differential protein expression by autoinducer-1 in Escherichia coli
J. E. Momb and J. B. Schineller
Department of Chemistry; Humboldt State University
Cell density dependent regulation or quorum sensing with a
diffusible signal molecule or autoinducer is used by many species
of bacteria to regulate gene expression. In Escherichia coli,
Autoinducer-1 (AI-1, N-(3-oxohexanoyl)-L-homoserine lactone) has
been shown to regulate expression of genes required for cell division
and other fundamental cell processes. Affinity chromatography
and 2-D gel electrophoresis were used to isolate and characterize
proteins differentially regulated by AI-1. An affinity column
was prepared using a homolog of AI-1 and used to isolate AI-1
binding proteins. Isoelectric focusing was done using immobilized
pH gradient strips followed by SDS-PAGE and detection by silver
staining. Proteins were observed to be both induced and repressed
by AI-1.
Moriarty
Comparing Small Mammal Populations in Old-Growth Douglas-Fir Stands that Differ in their Shrub Understory
Katie M. Moriarty
Department of Wildlife Management; Humboldt State University
Forest carnivores such as the American marten (Martes americana) are strongly affected by the availability and diversity of prey. This study explores forest carnivore management by quantifying variation in small mammal communities with differing shrub cover in old-growth Douglas-fir (Pseudotsuga menziesii) stands. Surveying was conducted between June and August 2003. A total of 137 small mammals were captured over the 2,079 trap nights. Species captured included chipmunk species (Tamias spp.), deer mouse (Peromyscus maniculatus), western red-backed vole (Clethrionomys californicus), and Trowbridge's shrew (Sorex trowbridgii). Dense shrubs plots were considered to be those which had a high percent of under story cover (> 60%) from salal (Gautheria shallon) and rhododendron (Rhododendron macrophyllum); whereas, sparse shrub sites had no ericaceous vegetation and the low shrub cover (< 40%) consisted of tan oak (Lithocarpus densiflora). There was little difference between the total number of captures between dense and sparse shrub density areas: n = 73 and n = 64 respectively. However, the average individual weight on the dense shrub plots (x = 32.1) was significantly less than the sparse shrub plots (x = 62.0) (n = 37, df = 36, P < 0.0001). Individual weight was due to species composition differences, as sparse shrub sites were dominated by chipmunk and dense shrub areas harbored high numbers of red-backed voles.
Nachem
Children's Health Care in Mexico
Beverly F. Nachem
Department of Nursing; Humboldt State University
Nurses throughout the United States work with families who have emigrated from Mexico. In order to provide culturally sensitive care to children and their families, it is important to understand the family's previous experiences and expectations. Learning about the delivery of health care in Mexico will help nurses gain this understanding.
This poster provides a brief overview of the Mexican health care system and explains, with photographs and descriptions, some of the hospital policies and community health programs for children and their families. The expected roles of family members in three hospitals in Baja California Sur illustrate hospital policies regarding children and their families. Three community health programs that are in place throughout Mexico are be shown. These include the promotion of breastfeeding, immunization of children, and ORT (oral rehydration therapy) for children at risk for dehydration from diarrheal illness. Each of these programs has succeeded by using a variety of methods and approaches.
Paselk
A Modern Interpretation of a Medieval Torquetum
Richard A. Paselk
Robert A. Paselk Scientific Instrument Museum; Humboldt State University
The torquetum is a complex and sophisticated instrument characteristic of medieval astronomy and the Ptolemaic tradition. It could be used to make measurements in the three sets of astronomical coordinates: horizon (alt-azimuthal), equatorial, and ecliptic. It could also serve as a mechanical analog computer to inter-convert these sets of coordinates without the use of calculations, as well as to demonstrate the relationships of these coordinate sets. Modern scholars often attribute the torquetum's use largely for demonstration and "conspicuous intellectual consumption." Only two examples are known to survive from the middle ages. A few years ago I determined to build a torquetum based on medieval diagrams, Renaissance illustrations, and photos of surviving instruments that would be true to medieval design, materials, and methods of fabrication. For this poster I would like to address: 1) instrument design-I had to modify my original interpretation to create a functioning instrument, 2) traditional fabrication techniques as applied to this project, and 3) the functionality of the torquetum as a scientific instrument as determined by the use of my instrument. The instrument itself will be on-hand for demonstration and testing.
Presented previously at: XXII International Scientific Instrument
Symposium, September 29th to October 5th, 2003, The Mariner's
Museum, Newport News, Virginia.
Ratchford
Ant Species Richness and Community Structure in Darlingtonia Fens and adjacent Uplands
Jaime S. Ratchford1 and Nathan J. Sanders2
1Department of Biological Sciences; Humboldt State University and 2Department of Ecology and Evolutionary Biology; University of Tennessee
Ants are important players in most terrestrial ecosystems where they serve as scavengers, predators, prey, herbivores, and mutualists to a wide variety of other taxa. Ants are also indicator species for environmental stress and the diversity of other arthropods. Thus, understanding the factors that influence ant species richness and community structure may be important for understanding the functioning of ecosystems. In this study I examined a suite of environmental factors that influence ant species richness and community structure in two distinct habitat types in the Klamath-Siskiyou ecoregion. This region is biologically one of richest areas in North America with a vast array of unusual and endemic plants. However, we know very little about the ants of this region. Specifically, I asked three questions:
(1) What environmental factors influence ant species richness?
(2) Are ant communities in Darlingtonia fens distinct from those in adjacent upland habitats?
(3) Do ant species in these two habitats co-occur randomly?
Roberts
Ice, Eruptions, and Avalanches: Distinguishing Lahar Origins with Examples from Mount Shasta, California
Michelle Roberts
Department of Geology; Humboldt State University
Mount Shasta in northern California provides an ideal setting for studying lahars of three primary origins: Climatic fluctuations, eruptions, and debris avalanche transformations. Though multiple factors could be involved, there are characteristics in lahar deposits that are indicative of the triggering event. Climatically-induced lahars occur almost exclusively in drainages headed by glaciers, resulting from the rapid retreat of ice, or the failure of a moraine-dammed lake. As non-cohesive lahars, they become diluted as they progress downstream. Holocene lahars along Mount Shasta's largest drainage, Mud Creek, have formed levees containing one to two meter boulders; downstream the deposits form alluvial fans with smaller clasts. Headed by the Konwakiton glacier, Mud Creek has produced lahars into historic times. West of Mud Creek, unglaciated drainages have not produced lahars since the end of the last glaciation. One of these drainages contains a latest Pleistocene lahar that likely occurred as the ice receded, possibly resulting in the breach of a moraine-dammed lake.
Lahars with eruptive origins have large concentrations of pumice clasts several centimeters in size. A lahar on the Mud Creek fan contains pumice clasts up to 10 cm belonging to the Red Banks eruption 9700 14C years ago. Another characteristic of eruptive lahars is intensive oxidation from high heat, resulting in a red or pink color. The extent of eruption-induced lahars is dependent on the amount of ice and snow in contact with pyroclastic deposits, and they are often non-cohesive in behavior.
Debris avalanches transform into lahars through disintegration of avalanche blocks. High clay content in the avalanche matrix creates a cohesive lahar able to travel long distances. Deposits from an enormous debris avalanche which occurred ~350 ka on the north side of Mount Shasta have been recognized for years (Crandell, 1989), but there is evidence that this avalanche triggered lahars on the south flank of the mountain. A south-flank lahar similar in age to the avalanche contains large amounts of pumice, evidence that an eruption occurred prior to or coincident with the avalanche. Whether this avalanche occurred during a glacial period is unknown, though the large amount of water required to mobilize it would be readily available during extensive glaciation.
Presented at the 2003 International Union for Quaternary Research
Congress, Reno, Nevada.
Roth et al.
Contact and Attitudes toward Community Inclusion of Individuals with Developmental Disabilities
Carrie Moses Roth, Mary B. Gruber, Jill H. Furuoka, and Deborah K. Ewen
Department of Psychology, Humboldt State University
One of the goals of behavior analysts is to improve the quality of life for developmentally disabled persons by developing supports for appropriate interactions in community settings. This study investigated which types of contact experiences with developmentally disabled persons have the strongest relationship to attitudes toward community inclusion. This study surveyed 106 individuals, including 71 general community members and 35 staff members currently working with people with developmental disabilities. The survey included the Contact with Disabled Persons Scale (CDP; Yuker & Hurley, 1987), which had 20 items about contact experiences with developmentally disabled persons, to be rated for frequency on a 5-point scale from "Never" to "Very Often". The survey also included the Community Living Attitudes Scale (CLAS; Henry, Keys, Jopp, & Balcazar, 1999), which had 17 items about attitudes toward community involvement of developmentally disabled persons, to be rated on a 6-point scale from "Disagree Strongly" to "Agree Strongly".
Factor analysis of the Contact with Disabled Persons Scale yielded four separate factors, representing frequency of Pleasant, Supportive, Unpleasant, and Visitation types of contact experiences. The Community Living Attitudes Scale contained four subscales, representing attitudes toward Empowerment, Exclusion, Sheltering, and Similarity.
The staff members scored significantly higher than the community members on their amount of contact experiences with developmentally disabled people, including Overall Contact Experience (t(104 ) = 6.32, p < 0.001), Pleasant Contact Experience (t(104) = 5.47, p < 0.001), and Unpleasant Contact Experience (t(104) = 4.73, p < 0.001). The staff members and community members scored similarly to each other, however, on their attitudes toward community involvement of persons with developmental disabilities.
Pleasant Contact Experience correlated negatively with attitude toward Exclusion, for both community members (r(71 )= 0.234, p < 0.05) and staff members (r(35)= 0.397, p < 0.05). These correlations indicate that pleasant contact experiences are associated with greater disfavoring of exclusion and greater favoring of inclusion, by both community and staff members. Pleasant Contact Experience also correlated positively with staff attitudes toward Empowerment (r(35) = 0.392, p < 0.05) and Similarity (r(35) = 0.507, p < 0.01). These correlations indicate that pleasant contact experiences are associated with staff favoring empowerment of people with developmental disabilities, and with staff perceiving themselves as similar to persons with developmental disabilities. These findings indicate that pleasant contact experience with developmentally disabled persons is associated with favorable attitudes toward their inclusion in the community. The other types of contact experience, however, did not correlate significantly with inclusion attitudes.
These findings support the importance of the behavior analyst's role in facilitating pleasant interactions between developmentally disabled persons and community members. The behavior analyst can help both developmentally disabled and other community members acquire pleasant ways of interacting together. In so doing, the behavior analyst may also help increase the inclusive attitudes and welcoming behaviors of community members toward individuals with developmental disabilities.
Presented at the Association for Behavior Analysis Annual Convention, May 24, 2003, San Francisco.
Smith
Visualizing Timber Harvest Impacts
Doug A. Smith
Humboldt Watershed Council; Humboldt State University
An animated map of timber harvests in the Freshwater Creek watershed that flows into Humboldt Bay in Northern California has been produced. The GIS data was created by the California Department of Forestry for the years 1988 to 2001. The Freshwater watershed has been in the political spotlight because of repeated flooding caused by siltation that has filled in the river channel. The Humboldt Watershed Council has presented the case before the State and Regional Water Quality Control Boards to remedy the situation. The process used GIS software to export Escalated Postscript Files into a program called Image Ready created by Adobe. This program creates animated GIF files from image files. For each data year of the data set an image was exported. These images were then added to a project frame by frame and aligned. Text was added to summarize the percent of annual timber harvest in the watershed. The final slides show the cumulative visual effects and a view of current timber harvest activities.
The animation was presented to the Regional Water Quality Control Board in Spring 2002. Presented at the CALGIS Conference, San Jose, California. The handout was produced for a Humboldt ESRI Users Group presentation in 2003.
Project URL: http://thpsonlinenow.freeyellow.com/afreshanna5.html
Smith and Clark
n6-(o-Benzyne)chromium(0) tricarbonyl: A Computational Study
Joshua R. Smith and Ian T. Clark
Department of Chemistry; Humboldt State University
Calculations using density functional theory (B3LYP) revealed that n6-(o-benzyne)chromium(0) tricarbonyl exists as a minimum on the C6H4(CO)3Cr potential energy surface. The energy difference of the title compound and n6-(benzene)chromium(0)tricarbonyl was found to be comparable to free o-benzyne and benzene, around 100 kcal mol-1. The calculations imply that the benzyne chromium complex is a viable synthetic target, which will be a useful synthon of n6-(benzene)chromium(0) tricarbonyl.
Solem et al.
Helical Structures in Perfluoroalkanes: A Computational Conformational Investigation
Sadie E. Solem, Erin M. Brown, Robert W. Zoellner, and William G. Golden
Department of Chemistry; Humboldt State University
Complete conformational analyses of perfluoropentane, perfluorohexane,
and perfluoroheptane were carried out at both the semiempirical
PM3 and the ab initio Hartree-Fock RHF/3-21G(*) level of
theory using the PC SPARTAN Pro computational package.
These analyses indicated that the lowest energy conformation of
any perfluoroalkane is a helical structure. Further, the conformational
analyses demonstrated that helical or partially helical conformations
dominate the lower energy portion of the total conformational
manifold. The dihedral angle leading to helical structures in
these perfluorocarbons is approximately 43º compared to the
60º dihedral angle expected for the fully staggered, zig-zag
structure analogous to the lowest energy conformer seen in hydrocarbons.
Swanson et al.
Geomorphic and Structural Features of the Creeping San Andreas Fault and Long-term Creep Rate, Flook Ranch, Bitterwater Valley, California
Karl Swanson,1 Susan M. Cashman,1 and John N. Baldwin,2
1Department of Geology; Humboldt State University; and 2William Lettis and Associates, Inc.; Walnut Creek, California
Structural and geomorphic features at Flook Ranch (latitude
36.3983°N) on the creeping segment of the dextral San Andreas
Fault (SAF) have recorded deformation of late Holocene fan deposits.
A detailed survey of the fault zone shows two N35°W oriented
fault traces that bound a fault-parallel swale and merge to the
northwest into a single N45°W striking trace near the southern
end of a 1 km-long pressure ridge. We excavated a ~20 m long trench
(WLA T-1) across a prominent linear swale (~12 m wide) bounded
by low 0.5-m-high east- and west-facing topographic escarpments.
A ~10 m long trench (WLA T-2) was also excavated across a single
low southwest-facing escarpment 60 m northwest of WLA T-1 and
on the opposite side of an active fluvial channel. Abundant extensional
fractures extend across a width of 18 m in WLA T-1, and a width
of 4 m in WLA T-2; the greatest concentration of fractures coincides
with the topographic escarpments in both trenches. Extensional
fractures, likely accommodating deformation associated with aseismic
creep, rotate clockwise as they near the ground surface and are
oriented 20 to 30 degrees clockwise from the main San Andreas
Fault zone. A survey of an offset ~95 year old fence 100 m south
of WLA T-1 indicates the creeping zone is ~13 m wide and the fence
is dextrally offset 1.19 to 1.51 m. The long-term creep rate for
this segment of the SAF for the last ~95 years is 22-28 mm/yr.
This rate is lower than the previously reported historic creep
rate of 28-32 mm/yr based on 1983 measurements (Cotton et al.,
1986). A creepmeter ~25 m south of the fence indicates a 16-17
mm/yr creep rate between 1969 and 1995, but there is some question
whether or not the creepmeter extended across the entire width
of active deformation (Schulz, 1989). Colluvial wedge deposits
and liquefaction-related features were not observed in the trenches;
their absence strongly suggests that these deposits have not experienced
a large coseismic surface-fault rupture in the last ~1,000 years.
Teague and O'Gara
Effects of Copper on Giant Fiber Conduction Velocities in Lumbriculus variegatus
Matthew W. Teague and Bruce A. O'Gara
Department of Biological Sciences; Humboldt State University
The neurotoxic effects of copper exposure were examined in the freshwater oligochaete, Lumbriculus variegatus. Noninvasive electrophysiological testing indicated that copper exposure produced time-and concentration-dependent reductions in the conduction velocities of the medial and lateral giant nerve fibers (MGF and LGF, respectively). The conduction velocities of worms exposed to 0.1 ppm copper sulfate for two hours returned to normal levels within 24 hours after return to clean water. The conduction velocities of worms exposed to 0.05 ppm copper sulfate for eight hours returned to normal levels within 24 hours after return to clean water. Treatment with an antioxidant (ascorbic acid) may reduce the toxic effects of copper exposure on L. variegatus.
Topolewski and Dupree
Effectiveness and Use of Written Anti-suicide Contracts
A. M. Topolewski and J. L. Dupree
Department of Psychology; Humboldt State University
One of the ways of treating and managing suicidal ideation and intent that is expressed in psychotherapy is to utilize anti-suicide contracts. Such contracts are written or oral, and typically include a promise by a client to refrain from self-harm and to identify alternative behavior. Despite the seriousness of this issue, little research has been done to investigate the effectiveness or use of this technique.
This study surveyed 94 Marriage and Family Therapists (MFTs) from five counties in California, both urban and rural. A twenty-item questionnaire specifically designed for this study explored whether respondents considered written anti-suicide contracts to be effective, whether they themselves used such contracts, at what level of severity of ideation and intent the contract was indicated, and three additional independent items. Demographic variables included gender, years providing psychotherapy, professional setting, and past training in use of written anti-suicide contracts.
As a group, the MFTs had a broad distribution regarding whether or not they considered such contracts to be effective. There was no difference regarding effectiveness between the 78% who were trained to use contracts (M = 3.21, SD = 0.67) compared to the 21% without such training (M = 3.13, SD = 0.69) (p = 0.66). However, clinicians who were trained were significantly more likely to actually use them compared to the untrained (p = 0.001). Professional setting was not a significant factor. Of those MFTs (56%) who do use written anti-suicide contracts, most have the client write it up in their own words rather than using a standard form. Most give a copy to the client to carry around and they also maintain a copy in the clinical file. If a client refuses to sign such a contract, most would then seriously consider hospitalization. The decision to utilize such contracts increases with severity, unless involuntary hospitalization is already required. The majority (67%) was clearly neutral regarding whether there was research support for their use. MFTs were evenly distributed in opinion whether such contracts protected them from lawsuits.
Presented at the Annual Meeting of the Western Psychological
Association, Vancouver, BC (May 2003).
Wengert
Reproductive Success of Female Roosevelt Elk: Influence of Parasites and Condition
Greta M. Wengert
MGW Biological Surveys; Bayside, California and
Department of Wildlife; Humboldt State University
A mother's parasite burden and her general health may influence reproductive success. A female in poorer condition with more parasites may be less successful at reproducing and have less to invest in offspring during both gestation and post-natal care than a female in better condition with fewer parasites. In a herd of Roosevelt elk (Cervus elaphus roosevelti) in Sinkyone Wilderness State Park, Mendocino County, CA, mothers were in better physical condition at the beginning of the nursing period than non-mothers (p=0.036) and had fewer parasite genera than non-mothers (p=0.011). Mothers also declined in physical condition over the nursing period, but non-mothers did not. The physical stress and energy required to nurse offspring until weaning may deteriorate the condition of an elk cow, and this in turn may influence the pattern of investment in offspring.
Wengert and Gabriel
Do Pyrotechnics increase Waterbird Nestling Mortality on Indian Island in Humboldt Bay, California?
Greta M. Wengert and Mourad W. Gabriel
Department of Wildlife; Humboldt State University and
MGW Biological Surveys; Bayside, California
Indian Island in Humboldt Bay, California has been a continuously occupied rookery site of Great Egrets (Ardea alba), Great Blue Herons (Ardea herodius) and Black-crowned Night Herons (Nycticorax nycticorax) dating as far back as 1966. The area above Indian Island is also the site for the Independence Day pyrotechnics celebration for Eureka, CA, although studies have shown that human disturbance may increase mortality in waterbird nestlings. In 2001 and 2002, we quantified nestling mortality through ground surveys on the three nights preceding the pyrotechnics display, immediately after the pyrotechnics, and on the night following the pyrotechnics. We noted occurrences of general disturbance of the rookery, and whether it occurred during the pyrotechnics. Nestling mortality was increased by two nestlings due to the pyrotechnics in 2001 and one nestling in 2002. We observed a general disturbance in the form of flushing only among the Black-crowned Night Herons when the pyrotechnics began. However, there is not sufficient evidence to indicate that nestling mortality was significantly increased due to the pyrotechnics on Indian Island. These results may be important in the management of waterbirds in similar situations of human disturbance.
Wood
A Chemical Released from Host Acacia by Feeding Herbivores is Detected by Symbiotic Acacia-ants.
William F. Wood
Department of Chemistry; Humboldt State University
In Costa Rica, the plant-ants Pseudomyrmex spinicola and P. flavicornis are symbionts with the bullhorn acacia, Acacia collinsii. Individual acacias contain only one species of ants. The acacia gives shelter to the ants in hollow thorns. In addition, it feeds them a sugar solution at non-floral nectaries and provides fat and protein in the Beltian bodies that grow at leaflet tips. In return, the ants protect the tree from most arthropod herbivores. These ants have a distinct alarm behavior: When disturbed, the workers come out of the thorns, run much faster and turn more often in search of the source of a disturbance. It was noted that crushed leaves, such as produced from herbivory, would initiate ant alarm behavior. The leaves of this plant were crushed and the released volatile compounds were collected by solid phase microextraction (SPME) and examined by gas chromatography-mass spectrometry (GC-MS). This showed that trans-2-hexenal was the major compound released from the crushed leaves. Response to trans-2-hexenal was tested on 10 different colonies of P. spinicola and P. flavicornis. In the one-minute period after placing the trans-2-hexenal sample on this branch, the number of P. spinicola ants attracted was 20.6 ± 5.8 ants per colony (solvent control 5.3 ± 4.4); with all ants now displaying alarm behavior. In similar experiments with P. flavicornis, the initial solvent control averaged 8.1 ± 3.4 ants per colony, and the trans-2-hexenal sample averaged 21.4 ± 6.4 ants per colony. Hereto, alarm behavior was only observed during the trans-2-hexenal experiments. GC/MS analysis of whole ant extracts for both species was done to see if trans-2-hexenal was part of the ant alarm pheromone. No trans-2-hexenal was observed in the extracts of either species.
Wood et al.
Clitolactone: A Banana Slug Antifeedant from the Mushroom Clitocybe flaccida
William F. Wood,1 Thomas J. Clark,1 Debra E. Bradshaw,1 Brian D. Foy,1 David L. Largent,2 and Bradley L. Thompson2
Departments of 1Chemistry and 2Biological Sciences; Humboldt State University
Clitolactone, 5-(chloromethyl)-3-methyl-2(5H)-furanone, was isolated from sporocaps of the mushroom Clitocybe flaccida. The structure was determined by high resolution mass spectrometry (HRMS), electron impact mass spectrometry (EIMS), proton (1H) and carbon (13C) nuclear magnetic resonance spectroscopy (NMR), proton-carbon correlation NMR (2D 1H-13C COSY) and proton-proton correlation NMR (1H-1H COSY.) This mushroom is not eaten by the banana slug, Ariolimax columbianus, a mycophagist from the temperate rain forests of the Pacific Northwest. We found that clitolactone may be the reason slugs do not eat this mushroom, since slugs rejected 1.0 cm2 pieces of lettuce treated with 25 µg of clitolactone. This compound contains chlorine; organochlorine compounds have rarely been found in terrestrial organisms.
Zoellner et al.
A Computational Investigation of the Adsorption of Perfluoromethane onto an Idealized Nickel Surface
Joan M. Zoellner, William G. Golden, and Robert W. Zoellner
Department of Chemistry; Humboldt State University
The computational analysis of the adsorption of a perfluoromethane (CF4) molecule on a nickel surface is reported. Ideally, this analysis would examine the adsorption energy of multiple CF4 molecules on an "infinite" nickel surface. However, such an analysis is not possible with the program being used, PC SPARTAN Pro. Therefore, an idealized surface consisting of a single nickel atom was used. (Additional analyses using a larger idealized nickel surface are currently underway.) There are three different adsorption configurations that can occur in this system: The nickel atom may bond to one, two or three of the fluorine atoms of the CF4 molecule. These three configurations were each investigated at the RHF/3-21G(*) level of theory. No bonding occurs in the configuration in which a single fluorine atom from CF4 interacts with the nickel atom [F3C-F-Ni], nor does any bonding occur when three fluorine atoms from the CF4 interact with the nickel atom [FC-F3-Ni]. Bonding only occurs when two fluorine atoms from the CF4 molecule computationally interact with the nickel atom [F2C-F2-Ni]. These results have implications for the experimental investigation of the interaction of perfluorocarbon lubricants with metal surfaces.
Last modified 24 May 2004