Research Mentors & Projects
Marijuana (Cannabis sativa) is the most commonly used illicit drug in the United States. The main psychoactive ingredient of Cannabis sativa is delta 9–tetrahydrocannabinol (THC), which acts on the endogenous CB1 cannabinoid receptor. In marijuana users, activation of CB1 receptors has been found to produce various ‘aphrodisiac’ effects. However, these effects follow an inverted-u shaped dose response on sexual behavior and differ between men and women. To date, the results from studies investigating the role of the endocannabinoid system in female sexual behavior have not been consistent nor have the full range of measures of sexual motivation been tested. The present research project will investigate the effects of various drugs that activate or block neuronal endogenous cannabinoid receptors on sexual behavior in an animal model. All female animals will be tested for sexual motivation using a partner preference test as well as a mate choice test.
Apple snails belong to the most diverse family of freshwater snails. Apple snails within the genus Pomacea (Family Ampullariidae) already dispel stereotypes of the “average” snail with their aquatic-terrestrial nature, considerable size, and tendency to act as true herbivores versus algal grazers. This summer research project will focus on bringing together a mix of past work on predation, growth, and reproduction with a specific focus on the hatchling and juvenile life history stages. For those students interested in molecular applications, possibilities exist for a number of pilot projects that could utilize recent collections of apple snails from a research trip to Uruguay. Summer students could also work on envisioning projects that might develop into a research possibility in Uruguay for December 2014-January 2015.
The endometrium is a classical hormone-dependent tissue and the effects of estradiol (E2) on the physiology of the endometrium are well known. In addition to controlling reproductive tract structure and function, E2 has been shown to act as a mitogenic factor, aiding tumor initiation and progression as well as increasing motility and invasive capabilities. Studies in our laboratory have determined that claudin (CLDN)-3 and -4 are not expressed in normal uterine human tissue but are highly expressed in the endometrial cancer cell lines HEC-1A and RL95-2. The present study attempts to address the effect of E2 on cell motility and occludin expression and subcelluar localization in the endometrial cancer cell line RL95-2.
R391, a known Integrative Conjugative Element, expresses an error prone DNA polymerase which is capable of introducing mutations during the synthesis of DNA. R391-mediated mutagenesis has been shown to lead to the development of antibiotic resistance. Also located on R391 is a putative transcriptional repressor gene designated setR. This research project looks to characterize putative setR repressor and establish its role in regulating R391-mediated antibiotic resistance in bacteria.
The Georgetown salamander (Eurycea naufragia) is an endemic aquatic species known from only 15 sites in Williamson County. All known populations of the species are threatened by increasing urbanization, and the species is currently being considered for listing as an endangered species. This project will continue the long-term research and monitoring of two populations of salamanders. Students will conduct monthly visual encounter surveys at the two sites and will photograph all salamanders captured. We will utilize pattern-recognition software to uniquely identify salamanders based on melanophore patterns on the head. We will collect, compile, and analyze data on salamander abundance, movement, reproduction, and growth rates.
Chemistry & Biochemistry
Peptides designed to possess antimicrobial activity will be synthesized using Fmoc solid-phase peptide synthesis, and purified by HPLC methods. Purified peptides will be characterized by mass spectrometry, tested for antimicrobial properties against a panel of bacteria; effective peptides will be tested for their abilities to disrupt cellular membranes using a liposome model of bacterial membranes. Other experiments will include the testing v-ras transformed fibroblasts and control cells under nutrient deprived conditions to study the apoptotic and autophagic responses of the two cell lines.
Dialkyltitanium(IV) derivatives are proposed to react with α-halo ketones and aldehydes to produce cyclobutanols. The high strain energies of these organic moieties can be exploited in the synthesis of complex organic molecules of biological, agricultural, and industrial importance. Furthermore, because of their 1,2-dianionic nature, dialkyltitanium(IV) species are anticipated to react with a variety of other electrophiles to form five- and six-member rings.
Pre-requisites: At least one year of Organic Chemistry at SU.
Substituted alkyne derivatives are useful starting materials for the synthesis of conjugated organic molecules with many applications as organic light-emitting diodes, nonlinear optical materials, and materials with sensor capabilities for biomedical applications. The Sonogashira coupling reaction has been applied to the synthesis of various substituted alkynes. However, this method uses hazardous, carcinogenic solvents which are also converted into waste byproducts that cannot be recycled. Thus, the development of an efficient, safe, and environmentally friendly method is of great interest. The catalytic effect of several room- temperature ionic liquids (RTILs) will be studied, as they offer a reusable, “green,” and versatile solvent for a variety of organic reactions.
During the SCOPE program, Dr. Niemeyer plans to work with students to advance three on-going projects in her laboratory: 1) determining how plant growth affects anthocyanin levels and antioxidant properties of several purple basil cultivars; 2) quantifying the effect of cultivar on the phenolic composition and antioxidant properties of lemon balm; and 3) analyzing variations in phenolic levels and antioxidant activities among a large selection of Lamiaceae herbs.
Several gold(III) and copper(II) complexes have shown potential for cleaving DNA upon irradiation. These findings will be explored further during the Scope Summer Research Program. Specific focus will be on investigating the mechanism by which cleavage occurs and on the binding selectivity of these complexes. The gold(III) complexes, in principle, have the capability to bind covalently to DNA. This potential will also be investigated, and kinetics of such binding will be studied for those are found to bind to DNA in such manner.
A new hydrazone thiophene ligand is to be synthesized and subsequently reacted with copper, cobalt and/or nickel acetate or nitrate. The compounds, if produced, will be characterized by NMR, IR and melting point. An XRD structure will be determined if suitable crystals can be produced. The new compounds will then be tested using DNA, bacteria or other biological markers to determine if there is any potential biological activity.
DNA damage is thought to play a role in many human age-related diseases such as cancer, cardiovascular disease, and neurodegeneration and can arise from both exogenous factors and endogenous processes. The goal of this project is to evaluate the ability of antioxidants to protect DNA from DNA damage induced by free radicals. In another project, we will be measuring DNA damage levels in brain tissue of rats exposed to a widely abusive drug that binds to dopamine receptors, leading to the formation of reactive radicals.
Pre-requisites: At least one year of General Chemistry at SU. Organic Chemistry preferred.
Early starting blocks in competitive swimming were flat and simply elevated the swimmer above the pool so the swimmer could dive from an increased height. Block design began to incorporate an inclined platform to promote the production of more horizontal force and to facilitate forward movement. Recent design changes have introduced the use of wedge on top of the inclined platform (similar to that used in track and field) to further increase the horizontal force production. This research project will evaluate the effect of manipulating the platform inclination with a fixed wedge design. It is hypothesized that by reducing the platform inclination, takeoff angle will increase thus producing a more favorable trajectory.
The topic of difference equations is not covered in the typical undergraduate curriculum, and yet some is accessible to a motivated student with a solid high school math and science background. Difference equations lend themselves to study at a variety of levels; some work can be accomplished with a high school background, and yet advanced mathematics can also be included. This type of mathematics lends itself well to inquiry-based and interdisciplinary research by undergraduates.
Most robots contain a variety of sensors, an electromechanical system that allows them to move and a computer that controls everything. Today, robots have the capability to learn, to act autonomously, and to interact with humans and their environment. In this project, students will work to use these abilities to create a robot that can perform many of the tasks needed to run a small farm.
This SCOPE project involves an international monitoring campaign of the super massive black hole in Seyfert 1 galaxy NGC 5548. Ultraviolet spectral data from the Hubble Space Telescope will be combined with optical images and spectra from multiple ground based observatories. Analysis of the data will enable understanding of the structure and physics of the material swirling around the black hole.
Wind data collected from Post-tropical Cyclone Sandy will be analyzed and compared with data collected from Hurricanes Ike and Dolly (2008) as well as data collected from the extratropical environment. Subtle differences have been observed in the windfield between wind generated by tropical cyclones and wind generated synoptically in the extra-tropical environment, and it is anticipated that examination of wind data from this third type of environment, the post-tropical storm, or nor’easter, will add to our understanding of the behavior of wind and the factors which influence turbulence in the boundary layer during an extreme event.