Volume 12, Issue 4, November 2015

Volume 12, Issue 4, November 2015 interactive high-resolution pdf


p. 2 A Historical Context for Undergraduate Research: The Contribution of Wilhelm von Humboldt by David Vampola


p. 5 Category Theoretic Interpretation of Rings
by Edward Poon


We enhance the category of rings and the category of idempotented rings to 2-categories. After doing this, we prove an equivalence of 1-categories and 2-categories between the category of rings and the category of small preadditive categories with one object and between the category of idempotented rings and the category of small preadditive categories with finitely many objects. Under these equivalences, we demonstrate some analogues between notions in category theory and ring theory.
Ring, Idempotent, Preadditive Category

p. 31 Effect of Manual Ivy Removal on Seedling Recruitment in Forest Park, Portland, OR by Katelin D. Stanley & Dr. David W. Taylor


English and Irish ivy (Hedera helix and H. hibernica) are invasive lianas which have become especially intrusive in the Pacific Northwest, as evidenced by their invasion of many areas in Forest Park, Portland, OR. The most common strategy for ivy control is currently manual removal, though the potential consequences of this method have not been well studied. The purpose of this study was to evaluate the effectiveness of manual ivy removal with respect to its influence on native plant diversity, abundance, species richness, and evenness by comparing these parameters in 1-m2 plots manually cleared of ivy to paired control plots. Prior to plot establishment, evidence of deer herbivory of ivy was observed at this site. Four weeks after manual removal, treated plots were less diverse and hosted a lower abundance of native plants than control plots. Ten weeks after ivy removal, treated and control plots were equally diverse, and treated plots showed greater abundance of plant cover than controls. This trend persisted at twenty-six weeks after treatment. Treated and control plots were not significantly different in species richness or evenness at any time. These results suggest that manual ivy removal temporarily disturbs native plant life, but the negative effects are overcome as quickly as ten weeks after treatment, at which time native plants are more successful. Manual removal as a method to control ivy in this region appears effective within one growing season.
English Ivy, Irish Ivy, Invasive Species, Pacific Northwest, Forest Park, Hedera helix, Hedera hibernica

p. 43 Imaging Noisy Seismic Data using a One Dimensional Inverse Scattering Algorithm by Bogdan G. Nita & Christopher Smith


We test the capability of an inverse scattering algorithm for imaging noisy seismic data. The algorithm does not require a velocity model or any other a priori information about the medium under investigation. We use three different geometries which capture different types of one-dimensional media with variable velocity. We show that the algorithm can precisely locate the interfaces and discover the correct velocity changes at those interfaces under moderate noise condition. When the signal to noise ratio is too small, the data is de-noised using a threshold filter and then imaged with excellent results.
Seismic Imaging, Inversion, Amplitude Correction, Scattering Theory, Noise, Threshold Filter. 2000 MATHEMATICS SUBJECT CLASSIFICATION 86A22, 35J05, 35R30.

p. 57 Effect of Native American Bean-corn Biculture Planting on Free-living Bacterial Abundance and Plant Growth by Heather A. Miller, Justin Fiene & Tamara L. Marsh


Native American tribes with bountiful harvests. Today it is widely recognized that this associated intercropping system derives much of its success from symbiotic bacteria (e.g. Rhizobium). These bacteria colonize the roots of leguminous plants, allowing them to fix atmospheric nitrogen into ammonia. However, the effect of this intercropping practice on the microbial community, independent of the effect of the symbiotic nitrogen-fixing bacteria, is not well understood. Therefore, a study was designed to model the effects of simultaneously intercropping bean and corn on the abundance of aerobic heterotrophic, free-living nitrogen-fixing, and symbiotic nitrogen-fixing bacteria, as well as plant growth and fecundity markers. In parallel, the benefits mediated by rhizobia were evaluated by inoculating a duplicate set of treatments with N-Dure, a rhizobia-containing inoculum. Native American varieties of pole-bean (Phaseolus vulgaris L.) and corn (Zea mays mays L.) were planted in monoculture and biculture treatments. All cultivations were maintained under greenhouse conditions for 52 days with daily watering and no additional fertilizer or microbial amendments. Although a significant increase in weight per plant was noted for the inoculated biculture when compared to either the inoculated bean or corn monocultures (p ≤ 0.05), the abundance of heterotrophic and free-living nitrogen-fixing bacteria did not show a significant change from the related controls, with or without inoculation. However, symbiotic nitrogen-fixing bacteria, as measured by root nodulation, increased significantly (p ≤ 0.05) for the inoculated biculture and single planting. Thus, these data confirm that corn benefited from this associated intercropping system as shown by an increase in plant biomass that can be attributed to Rhizobium. However, neither the legume-bacteria symbiotic relationship nor the increase in plant biodiversity resulting from this intercropping practice appears to have had significant effects on the abundance of the two common soil-associated bacterial groups evaluated, though further research would be necessary to fully assess the changes to heterotrophic bacterial diversity at the species level.
Three Sisters; Nitrogen-fixing Bacteria; Inoculation with Rhizobia; Plant Growth Promoting Bacteria; Soil Microbial Biota; Corn and Bean Simultaneous Planting.

p. 73 Point-Spread Function (PSF) Photometric Analysis of Open Clusters: Melotte 72 & NGC 2158 by Muhammad Awais Mirza & Zain Rahim


Point Spread Function (PSF) photometry of open star clusters Melotte 72 and NGC 2158 was performed using g and r band data from the Sloan digital Sky Survey (SDSS) Data Release 7. Instrumental magnitudes of stars in both bands were transformed into calibrated magnitudes using standard equation. Color-Magnitude (CM) diagrams were produced and compared with the SDSS isochrones for AB stellar system for different ages and/or metallicities. The objective of this study was to determine the physical parameters (age, distance, metallicity, reddening) of open clusters from CM diagrams. The best fit isochrones were used to estimate cluster parameters. The observed parameters were then compared with the WEBDA data base.
PSF Photometry, Melotte 72, SDSS, NGC 2158, Isochrone Fitting, IRAF

p. 79 Synthesis of a MUC1 Mucin Cyclic Dimer Peptide and Its Antibody Binding Properties as Revealed by STD-NMR by Cheng Her & Thao Yang


In a previous study we showed that the shortened MUC1 mucin peptide GVTSAPD could bind monoclonal antibody (mAb). We proceeded on to make a cyclic peptide of the same sequence to see if it would be more effective in binding antibody. We were able to synthesize and isolate two different cyclic mucin peptides: 1) a monomer cyclic peptide with sequence GVTSAPD which we did not study due to difficulties in achieving homogeneity, and 2) a dimer cyclic peptide with sequence GVTSAPDGVTSAPD that was successfully isolated and studied. We describe here the results of the dimer cyclic peptide-antibody interactions obtained by Saturation Transfer Difference NMR (STDNMR). The results indicated that the protons of all residues experienced STD effects, notably being more pronounced at Pro, Val, Ala and Asp compared to the linear peptide GVTSAPD. The Pro residue exhibited STD peaks for all its side chain protons with stronger intensity at ProHγ while Ala, Val and Thr are localized to methyl groups.
Muc1 Antibody Recognition Epitope, STD NMR, Mucin Peptide-antibody Interactions, Cyclodimer Peptide.

p. 93 Methods for Essential Tremor Assessment: Acoustic Tremor Monitoring (ATM) and Rhythmic Spirals (RS) Methods by Emily Hart, Caroline Chow, Patricia Stan & Daniel King


There are several techniques of monitoring essential tremors, but there is not yet a standard method developed for the field. A quantitative way to track effects of medication and/or lifestyle treatment would be beneficial for future research in prevention or regression of essential tremors. The two methods evaluated are acoustic tremor monitoring (ATM) and rhythmic spirals (RS). The novel ATM measurement quantifies frequency and amplitude quickly and cost effectively. The tremor patient holds a microphone close to a speaker playing a single frequency tone. The Doppler Effect caused by the shaking microphone distorts the sound recording, and the encoded tremor information can be retrieved by using the Fast-Fourier Transform algorithm. The second method, RS, can be used by patients at home to measure frequency. The RS method is similar to the classic Archimedes spirals, but uses a different form and is timed which allows for the calculation of tremor frequency. The RS and ATM methods produce statistically similar frequency measurements, although ATM has greater precision.
Essential Tremors, Archimedes Spiral, Accelerometry, Spiral Analysis, Acoustic Tremor Monitoring, Rhythmic Spirals.