Fusion energy could be the solution to large scale energy production. In the effort to produce sustainable fusion energy, fusion reactor devices known as tokamaks and stellarators have been built to harness the fusion process using magnetic fields to confine plasmas, the fusion medium. The Compact Toroidal Hybrid (CTH) is an experimental tokamak-stellarator hybrid built to better understand the equilibrium and stability of magnetically confined plasmas. To aid in this endeavor, a Thomson scattering system is under development at the Auburn University Physics Department to measure CTH plasma temperature and density profiles. Thomson scattering, the classical interaction between light and free charged particles, is known to be a successful plasma diagnostic for this purpose. CTH plasma impurity line measurements are currently underway to ascertain the suitability of using 532nm as the scattering wavelength. This includes identification of plasma impurities and calculations of their relative abundances. Plans for high sensitivity, low noise measurements of Thomson scattered light are also in design.
Matthew Hall, Chemistry & Biochemistry
Mentor: Michael Squillacote
The initial photochemical event in vision is the absorption of light by retinal, a polyene which is attached to the protein opsin, in the complex called rhodopsin. When a photon of light is absorbed by this molecule a very rapid cis - trans double bond isomerization occurs about the 11- 12 double bond. We have been trying to understand the photoisomerization process by investigating the regioselectivity of the photoismerization of model diene systems. In particular, we are examining if steric effects are the driving force that causes the 100% specificity in the photoisomerization of retinal.
A mother's diet can have many lasting impacts on the phenotype of her young that can impact its reproductive fitness. The goal of this research is to explore the mechanisms responsible for this interaction by evaluating the relative expression of two neuropeptides, GnRH and RFRP-3, in the house mouse brain. These neuropeptides are both intimately involved in the regulation of reproduction with GnRH stimulating and RFRP-3 inhibiting reproductive maturity. Neurons will be quantified in each individual brain via microscopy and data will be compiled to determine the correlation between the quantities of these neurons and the reproductive output of these mice.
When an astronomer wants to know anything about an astrophysical object, besides simply what it looks like, he or she points a telescope at it and counts the photons that it gives off. The astronomer then divides them into a histogram with bins based on their wavelength. This is called a spectra. From this information alone, the astronomer can calculate what condition the particles that made up the object must have been in. For example, how hot were they, how dense were they, etc... In order to do this, an astronomer needs to know what the different atoms a star could be made of will do (i.e. what photons it will give off) in certain conditions. The trouble is that due to the fact that you cannot solve most quantum mechanical systems precisely, it is currently impossible to do this with a level of precision that makes uncertainty in our calculations ignorable. This is where my project comes in. Currently, if an astronomer takes the spectra of a star and uses the best available software to calculate its temperature, the software will say "this star is about 5000 degrees Kelvin." The goal of our project is to make this prediction a little more "honest" so to speak. Essentially what the project's goal is to say "due to the known uncertainties in quantum mechanical calculations, this star is somewhere between 4500K and 5500K."
My undergraduate research has focused on the small Hawaiian shrimp Halocaridina rubra as well as two freshwater crayfish species, Cambarus englishi, and C. halli, found in Alabama. This work includes 1) how evolutionary history and environmental factors influence the varying coloration of H. rubra populations and 2) elucidating the genetic structure of C. englishi and C. halli populations of the Tallapoosa river basin. This research has yielded an improved biological understanding of these organisms as well as valuable insight for planning future conservation efforts for these species.