https://doi.org/10.33697/ajur.2004.001
There Is Truth And Beauty In Undergraduate Mathematics Research
https://doi.org/10.33697/ajur.2004.002
Author(s):
Dele Oluwade
Affiliation:
Mathematics and Computational Sciences, American Journal of Undergraduate Research, Dewade Science Clinic, Ibadan, Oyo State NIGERIA
Isolation of Microsatellite Loci in Sceloporus grammicus (Squamata, Phrynosomatidae)
https://doi.org/10.33697/ajur.2004.003
Author(s):
Patrick H. Degnan and Elisabeth Arévalo
Affiliation:
Department of Biology, Providence College, Providence, RI 02918-0001 USA
ABSTRACT:
The mesquite lizard (Sceloporus grammicus) exhibits multiple Robertsonian chromosomal rearrangements (mainly centric fissions) resulting in several cytotypes. In a transitional environment from oak-pine forests to a drier xeric habitat in central Mexico, two cytotypes (F5: 2n = 34 and FM2: 2n = 46) are known to hybridize. A partial genomic library was constructed from S. grammicus genomic DNA and then screened for microsatellites. Microsatellites are short tandem nucleotide repeats that have near universal occurrence in all eukaryotic genomes. Microsatellites exhibit variable length polymorphisms that can be characterized and utilized as genetic markers for population studies. Thirteen microsatellite arrays were isolated from the S. grammicus genomic library and PCR primers were designed in the flanking regions for the amplification of these alleles. These microsatellite loci would be the primary tool used to answer behavioral, ecological, chromosomal and evolutionary questions that influence the maintenance of this hybrid zone.
https://doi.org/10.33697/ajur.2004.004
Author(s):
E.J. Chamberlin and M.W. Roth
Affiliation:
Physics Department, University of Northern Iowa, Cedar Falls, Iowa 50614-0150 USA
ABSTRACT:
Constant particle number, density and temperature (N, ρ, T) Molecular-Dynamics simulations are used to study second layer promotion and melting in a complete monolayer of krypton deposited onto a graphite substrate. In order to study the vertical behavior of the system and its relationship to melting, artificial horizontal constraints are introduced and their effects are systematically monitored. We find that horizontally confining each atom within an impenetrable cylinder increases the melting temperature Tm and causes melting to be less dramatic. The results also suggest that there is a limiting case of there being no transition for a sufficiently small confining cylinder. Vertical excursions of the adsorbate atoms increase at the onset of melting. The system subsequently goes through a vertical transition with increasing temperature, including second layer promotion followed by extinction of the partial second layer and the presence of a sparsely populated first layer and a large population of desorbed atoms. Horizontal confinement stifles true second layer promotion, causing the atoms to spend less time in the second layer at a given temperature and resulting in a thermal blurring of the adlayer, suggesting that in-plane fluctuations are a necessary part of the layer promotion mechanism. Horizontal confinement also raises the temperature where the vertical transition occurs but does not affect its sharpness or temperature extent.
Isoflavone Content of Kansas Soybeans
https://doi.org/10.33697/ajur.2004.005
Author(s):
M. Swanson, M. Stoll, W. Schapaugh, and L. Takemoto
Affiliation:
Division of Biology and Department of Agronomy, Kansas State University, Manhattan, Kansas 66506 USA
ABSTRACT:
Isoflavones occurring in soybean seed have been thought to have a positive effect on the health of humans, especially in cancer prevention. This positive impact may be a result of their antioxidant properties, estrogenic activity, or a combination of mechanisms. The purpose of this study was to quantify and compare different levels of isoflavones in various Kansas soybean cultivars. Seeds of four different cultivars grown in 2001 at three different locations were analyzed. There were significant differences in total and individual amounts of isoflavones across both cultivars and locations. These results demonstrated a large variation in isoflavone content in different cultivars grown in different locations, suggesting that selection of cultivar and growing location are important parameters in optimizing the isoflavone content of soybeans grown in Kansas.