STRATA

STRATA, the STudent Research, Academic, and Talent Archive, is a collection of selected Fort Lewis College student work, including undergraduate research, senior seminar papers, published works, conference presentations, and other creative and artistic projects. Search by name, subject, title, or academic department.

Pages

The Role of Cutaneous Sensory Feedback During Running
Gait and locomotion patterns are shaped by sensory feedback and input from the outside environment. Many different sensory systems including visual, vestibular and somatosensory, contribute to the overall control of gait. The plantar surface of the foot is the only part of the body to constantly be in contact with the ground during bipedal locomotion, as a result sensory information from cutaneous receptors to thought to influence human gait patterns. The lack of information from cutaneous receptors has been shown to affect kinematic variables during human walking. However, the role of cutaneous feedback during running is not well understood. The aim of our research was to specifically minimize cutaneous feedback by anesthetizing the soles of the feet in order to further understand the role of cutaneous sensory feedback during running. We hypothesized that with loss of cutaneous feedback from the plantar surface of the foot individuals would run with similar mechanics in the barefoot and shod conditions.
The Role of Deep Pressure Sensory Feedback During Gait
It is known that patients with diabetic peripheral neuropathy (DPN) have an altered gait due to sensory deficits in the feet. Footwear is also known to alter gait due to the difference in sensory input. This study attempted to confirm that DPN patients experience a gait change due to an afferent proprioceptor deficit and provide further evidence that footwear will alter gait. Subjects (n=11) participated in two testing sessions that included a baseline testing and testing with a lidocaine induced tibial nerve block to mimic DPN. Sixteen repeated-measure ANOVA tests were conducted comparing shod and barefoot, in both the normal (BF, SHOD) and anesthetized conditions (BF_ANEST, SHOD_ANEST). Separate analyses were conducted for walking and running. Dependent variables consisted of 3D kinematics and kinetics. Significant differences were found between shod and barefoot conditions in terms of velocity during run, GRF in the vertical plane during run, and GRF in the anterior-posterior plane during walk and run. These findings are consistent with previous research comparing barefoot and shod running and support the notion that shoes influence gait and can worsen the position awareness and stability of a person's body. Significant differences within footwear conditions (e.g. between barefoot and barefoot anesthetized) were not observed, which indicates that sensory feedback from deep pressure receptors does not play a major role in influencing gait. These results conclude that there is a significant change between barefoot and shod, but cannot support that it is the afferent proprioception deficit that causes patients with DPN to alter their gait.
The Role of Inflammatory Signaling Mediated Through NF-κb in Metformin Induced Apoptosis of MCF-7 Cells
The common AMPK-activating diabetes drug Metformin has received considerable attention from the research community as a potential apoptosis causing agent for certain breast, prostate, pancreatic and colon cancers. Upon Metformin's activation of the cell's chief energy sensing factor, AMPK, many downstream pathways elicit apoptosis-favoring responses. In this study the goal was to investigate the relative contribution of AMPK's inhibition of the inflammatory pathway to apoptosis in breast cancer cells. Specifically, Metformin prevents the inflammatory pathway's chief transcription factor, NF-kB, from trans-locating into the nucleus. To test this a western blot was performed following differential centrifugation to determine if Metformin could prevent NF-kB translocation to the nucleus as well as testing whether the inflammatory activator Prostratin could preserve NF-kB's translocation, despite Metformin treatment. Apoptosis was quantified via flow cytometry to determine if the combined treatment of Prostratin and Metformin was different from Metformin treatment alone. The combined treatment of Metformin and Prostratin displayed significantly greater translocation than Metformin treatment alone, however, Metformin or Prostratin treatment alone displayed no significant difference relative to the control. In addition there was a statistically greater extent of apoptosis in Metformin treatment alone than the combined Metformin and Prostratin treatment. Since there was no statistical difference between control and Metformin as well as Prostratin treatments in NF-kB translocation, the observed differences in apoptosis cannot be attributed to differences in inflammatory pathway activation. Additional pathways activated through Prostratin's side activation of Protein kinase C could also be implicated in reducing apoptosis in cells that were also treated with Metformin.
The Roots of Eugenics: Key Shifts in the Early Development of Eugenic Ideology, 1869-1883
This thesis attempts to establish a distinct timeline in the development of the idea of Eugenics, which is the theory that a superior race of humans can be created through the manipulation of marriage, reproduction, and genetics. The most important changes in eugenic ideology occurred not in the 1900's, but between 1869 and 1883, the years between which Francis Galton published his theories on Eugenics. In 1869, Eugenics was simply a theory on how human traits, such as intelligence and morality, might be hereditary; however, by 1883, the idea had already evolved into a radical philosophy, due to the influence of Darwinism, scientific racism, and Progressive Era activism. This research was conducted by analyzing the works of early Eugenicists and contemporary scholars such as Cesare Lombroso, Ernst Haeckel, and Ludwig Böchner; secondary sources analyzed the existing scientific and social environments that influenced these scholars. Significant changes occurred between 1869 and 1883, leading to a new understanding of Eugenics before it came to prominence in the 20th Century.
The Shapes of Numerical Ranges of Matrices
We will discuss numerical ranges of matrices, primarily focusing on the shapes they can take. We will present an in depth proof of the Elliptical Range Theorem, the Toeplitz-Hausdorff Theorem and several others. We are particularly interested in normal and almost normal matrices. Much of our research came from papers written by Rudolf Kippenhahn, Chi-Kwong Li, Karl Gustafson, Tyler Moran and Ilya Spikovsky.
The Song of the Light People
Poem by Courtland Hopkins from Fall 2012 - Winter 2013 issue of Images.
The Sum of Their Parts: Assessing Drifting and Double Zonal Osteons Within Medieval Kulubnarti, Nubia
Histological studies of bone represent an effective means of reconstructing health and estimating age in ancient populations through the analysis of the frequencies and sizes of discrete remodeling events. Although secondary osteons have been studied extensively, drifting and double zonal osteons are atypical osteons that are not entirely understood. Previous research suggests that drifting osteons may be related to age and double zonal osteons may be associated with periods of physiological stress. The purpose of this study is to determine whether either of these variables varies predictably with age or differs between the sexes and consider the possible implications for understanding health. In this study, rib thin sections from individuals interred at a medieval cemetery from Kulubnarti, Nubia (n=51), were used to assess how drifting and double zonal osteon frequencies relate to age and sex. It was hypothesized that both drifting and double zonal osteons would relate to age, that osteon frequencies would differ between the sexes, and that aspects of growth, development, and health could be inferred for the Kulubnarti population. Thin sections were observed using a compound light microscope. Results show only a weak negative correlation between drifting osteon frequency and age (Spearman's rho = -0.210). Double zonal osteon frequency shows a strong inverse correlation with age (Spearman's rho, p= -0.572). There was no statistically significant difference between the sexes (Mann-Whitney U, p=0.118).These data suggest homogeneity and continuity between the sexes at Kulubnarti and a strong negative correlation between these osteon types and age. Previous research on the Kulubnarti sample has demonstrated the presence of generalized stress. In this sample, double zonal osteons decrease with age supporting the hypothesis that these atypical osteons represent periods of growth arrest, as individuals with more double zonal osteons appear to have a higher risk of dying. Previous studies suggesting drifting osteons decrease with age may be supported by the current study, although further research into the cause of this osteon type is needed, whether for mineral absorption or as a reaction to strain gradients. However it is unclear whether the patterns suggested by this study are always present, specifically for double zonal osteons. Future histological studies should note the negative correlation between both drifting and double zonal osteons to age.
The Summons
Poem by Lydiah Class-Erickson, published in the Fall 2013-Winter 2014 issue of Images
The Testing and Feasibility of Piezoelectric-Excited Millimeter-Sized Cantilevers to Detect Pathogenic Strains of Escherichia Coli in Third World Water Sources
With contaminated water supplies being one of the world's greatest sources of preventable waterborne illnesses, this project's scope is focused on the construction, testing, and analysis of several piezoelectric-excited millimeter-sized cantilever (PEMC) biosensors. The cantilevers will be constructed by attaching lead zirconate titanate (PZT) sheets to glass plates such that the glass acts as a vibrating attachment zone for pathogenic cells. The biosensor is thus essentially a resonant microelectromechanical system (MEMS). This approach allows for measurements of mass to be taken utilizing two phenomena, resonant frequency dependency on mass and the piezoelectric phenomena. Using a simple frequency generator to stimulate the PZT transducer, the resonant frequency of a cantilever can be determined by a series of voltage measurements to model impedance of the system. These impedance models have a certain quality (Q) which is determined by geometric and material constraints of the sensor. For testing the biosensor, the immobilization of Escherichia coli O157:H7 species specific monoclonal anti-bodies (MAb) to the glass will be conducted using techniques described the literature. This will allow for the mass of the cantilever to rise when in the presence of O157:H7 E. coli cells. Then finally, using a cell counting device, control samples of heat killed O157:H7 cells will created such that calibration and accuracy of the biosensor can be measured. The feasibility of a Piezoelectric-excited millimeter-sized cantilever (PEMC) to detect pathogen Escherichia coli (E. coli) O157:H7 in water sources will be analyzed under constraints brought forth from the Engineers Without Borders organization. The design and research will include an analysis of durability, accuracy, maintenance, theoretical modeling of cell attachment to the cantilever, and cost for a "biosensor package".
The Timing and Emplacement of the Heart Mountain Detachment at White Mountain and Silvergate, Wyoming: Detritial Zircon and Anisotropy of Magnetic Susceptibility Analysis
The Eocene Heart Mountain detachment (HMD) is a rootless low angle normal fault that moved upper plate Paleozoic rocks up to 50km southeastward from the Absaroka Mountains into the western margin of the Bighorn Basin. The detachment is preserved over an area of 3400 km2 and occurred as a result of a lateral volcanic eruption similar to the eruption of Mount Saint Helens. Basal carbonate ultracataclasite (CUC) fault breccia marks the detachment plane of the HMD. At White Mountain, eight CUC dikes have been injected vertically (~120 m) from the bedding plane detachment CUC into the overlaying Mississippian Madison and Bighorn formations, and another CUC injectite is located at Silvergate closer to the break-away portion of the detachment. These injectites are evidence of forceful upward motion of fault gouge material during the emplacement of the HMD and are anomalous to all fault systems as they have a disproportional relationship between fault offset and cataclasite injection. At White Mountain the CUC is injected ~40 times farther into the hanging wall than would be expected for a normal fault with one episode of motion. To further understand the timing and emplacement of the HMD we analyzed the anisotropy of magnetic susceptibility (AMS) and the age of zircons within the CUC injectites. AMS analysis of the nine injectites show high variability in Kmax and Kmin values, suggesting a violent intrusion of fault gouge material. AMS samples were collected at the bottom, middle and top of CUC-4 and the resultant magnetic fabric changes from chaotic AMS orientations to orientations consistent with a vertical flow from bottom to top. At the top, Kmax values become more parallel to the injectite, suggesting a greater time and distance for the carrier mineral (magnetite) to align itself. LA-MC-ICPMS analysis of zircons from the CUC injectites and igneous dike intrusion at White Mountain provide similar ages of 48.8 ± 0.9 Ma which are within error of ash deposit ages at Jim Mountain (49.8 ± 1.1 Ma) and Hominy Peak (49.1 ± 0.75). These corresponding ages mark the timing of the eruption that liberated the HMD upper plate Paleozoic rocks to 48.8 Ma. The data reported in this paper support the hypothesis of volcanic landslide induced, catastrophic emplacement of upper plate rocks as opposed to slow moving allochthon models.
The U.S. Forest Service and Fire
A portfolio focused on the area of fighting wildfires in concern with the U.S. Forest Service and the past actions that has caused problems to the forests to strategies that have been attempted to fix these problems. The portfolio also maps three fires that have occurred during the summer of 2012 in Colorado to look at a correlation between firefighting priorities dependent on the average cost of housing in the areas of those fires.
The Veracity of the Historical Details in Javier Cerca's Novel Soldados De Salamina
"The Spanish Civil War (1936-1939) left a wound in the Spanish population that has persisted to this day. Less than a decade ago the Spanish government passed the Historical Memory Law which facilitated the exhumation of fosas comunes, common gravesites in which tens of thousands of war victims were anonymously buried. Upwards of seventy novels have been written about the war, including ¡Otra maldita novela sobre la guerra civil! [Another damn novel about the civil war!]. Javier Cercas's Soldados de Salamina (2001) stands above the rest. This critically acclaimed, award-winning narration focuses on the legend of the execution of Rafael Sánchez Mazas, the ideological founder of the fascist party that initiated and won the war. Unlike his forty-nine fascist counterparts who were executed by firing squad in a chaotic bout, Sánchez Mazas was able to escape unharmed and hide nearby. According to the legend, moments later Sánchez Mazas found himself staring down the barrel of a Republican soldier's gun who, for an unknown reason, let him flee. Cercas, a washed-up novelist and newspaper columnist who knows just as little about the Spanish Civil War as his naïve readers, narrates his investigation of the incident almost seventy years later. He consults various archives, books, and videos and conducts interviews with Sánchez Mazas's family members and the people he met soon after surviving the execution. Despite this, the metaliterary, or self-conscious, qualities of the novel complicate the authenticity of the historical details it presents. Cercas narrates every aspect of his investigation, including phone calls that he misses and even his indecision on what to order from a restaurant during an interview. These meticulous tendencies lead the reader to trust Cercas who, only pages later, admits to lying about some of the most essential details. This presentation discusses some of the sources that Cercas consulted in order to determine how accurately and inaccurately the narrator depicts them. This project also juxtaposes the narrator's and presenter's conclusions about historical and literary truth and discusses how these two types of truth serve to aid the Spanish population in coping with the Civil War even eighty years after its final battle. "

Pages