Examples of Research Projects:
The research projects will be distributed among a range of science and engineering departments. The following descriptions are examples of student research projects:

Project Title - Insect Leg Adhesion and Self-Healing Rafts:

Background and Motivation: For terrestrial organisms, and particularly those that are flightless, most interactions between the environment and an organism is through their legs. Leg structure, shape, and design is essential for their foraging success, avoiding predation, and responding to novel environments. In addition, to supporting weight and improving mobility, legs and associated structures are important for helping organisms adhere to a variety of surfaces. The structures used for adhesion can also be co-opted for dealing with rough surfaces and in ants help some species form structures including bridges, bivouacs, and rafts.

Leg hairs and adhesive pads are essential for improving surface adhesion during foraging and other day to day activities. Secondarily leg hairs and adhesive pads can be used to increase connectivity between individual workers when forming structures (e.g., rafts).. Passive attachment through interlocking of tarsi (the “foot”) allows for ants to interconnect with minimal energy investment and allow for temporary adhesion. This process is also modular, allowing for structures to self-heal when disturbed or no longer needed and integrate when additional members are added. 

Problem Statement: If leg hairs and tarsi structures or other adhesion mechanisms are key to raft formation presumably they would only be found on S. invicta. However, leg and tarsi structures are similar between the two different species (and two different subfamilies), the structures may only be co-opted for improving raft formation in S. invicta. Similar structures would indicate the structures are more important for surface adhesion to a diversity of substrates and a possible explanation for the ecological dominance of the invasive L. humile and S. invicta.

The Development of Theragnostic Compounds Capable of Detecting and Catalytically Degrading Reactive Oxygen Species

Mentors: Christian Goldsmith (Chemistry and Biochemistry) and Dean Schwartz (Anatomy, Physiology, and Pharmacology)

Background and Motivation: The incomplete reduction of O₂ to H₂O during aerobic respiration results in the production of reactive oxygen species (ROS) such as superoxide (O₂^-), hydroxyl radical (•OH), and hydrogen peroxide (H₂O₂). High concentrations of these species can damage biomolecules, and excessive oxidative activity has been linked to inflammatory, cardiovascular, and neurological disorders as well as aging. The exact roles that ROS play in these conditions, unfortunately, remain unresolved. Patterns of oxidative stress could potentially be used to diagnose these conditions at earlier stages than is currently possible and could provide insight that could be used to develop more effective treatments.

Problem Statement: Current methods of assessing oxidative stress suffer from several drawbacks including 1) incompatibility with non-invasive in vivo imaging techniques, 2) false positives in response to O₂ or non-ROS analytes, 3) a lack of response without a co-analyte that can convert the ROS into a more reactive form, 4) a turn-off, rather than a turn-on, response to ROS, 5) instability of the sensor in aqueous and/or biological media, and/or 6) difficulty in assessing whether a signal results from sensor activation or the accumulation of a less emissive form of the probe. Treatment options for oxidative stress also require further optimization, and clinical protocols to alleviate oxidative stress do not currently exist.

It is hypothesized that redox-active quinols can be used to prepare compounds that can act as 1) turn-on MRI contrast agent sensors for H₂O₂ that display a negligible response to O₂ and/or 2) functional mimics of superoxide dismutases (SOD), which catalyze the degradation of O₂^- to H₂O₂ and O₂. In the body, H₂O₂ is further converted to H₂O and O₂ by catalase enzymes. The current project involves a great deal of interdisciplinary work, as the antioxidant activity and MRI properties are assessed with assistance from researchers at the AU College of Veterinary Medicine and the AU MRI Research Center.

Synthesis and Electrochemistry of Ternary Metal Oxides for Solar Energy Conversion

Mentors: Byron Farnum (Chemistry and Biochemistry) and Ryan Comes (Physics)

Background and Motivation: Research in the Farnum group currently explores the fundamental structural and electronic properties of nanocrystalline ternary metal oxides for solar energy applications. Specifically, the family of Cu^IMO₂ (M = Ga^III, Cr^III, Fe^III) delafossite materials behave as p-type metal oxides within a variety of sensitized solar cells architectures as well as direct photocatalysts for the reduction of H⁺/CO₂ reduction. The layered crystal structure of these oxides has been shown to yield anisotropic charge transport in the [100]/[010] directions as well as anisotropic particle growth, producing wide hexagonal plate-like nanocrystals.

Problem Statement: The anisotropic aspects of CuMO₂ nanocrystals can act as positive and negative features in regard to solar energy conversion, with rapid charge transport resulting in efficient charge extraction, but anisotropic nanocrystals resulting in decreased contact area between adjacent nanocrystals. In order to better understand these aspects and improve the overall performance of these materials, our research seeks to develop well-controlled synthetic methods in order to direct the growth of CuMO₂ nanocrystals to result in more isotropic morphologies. Through detailed characterization  of  chemical  and electrical  properties, we  are  able to  better understand  the   defect  chemistry  and   density  of  valence  band  states  as  function  of  these morphological changes.

CO2 Storage and Utilization in Subsurface Systems in the Southeastern US

Mentors: Ashraf Uddin (Geosciences) and Lauren Beckingham (Civil Engineering)

Background and Motivation: CO₂ is one of the leading causes of climate change and this project seeks to reduce point source emissions and store or utilize them for other viable means. The proposed research studies the potential to store and utilize CO₂in subsurface systems in the southeastern U.S. This includes safe, permanent, and economic storage of commercial volumes of CO₂ in regionally significant saline reservoir systems or utilization of CO₂ as working fluid for compressed energy storage in porous formations.

Problem Statement/Hypothesis: The objectives of this project are to enhance understanding of the subsurface geology in the southeastern US, their suitability as storage formations, and the interactions between the storage system and injected CO₂ [50-54]. This includes characterization of the petrophysical properties of the formation and evaluation of the fate of injected CO₂ in the system, including transport and transformation and corresponding evolution of formation properties. The research will expose students to field and laboratory research on the future of climate control in the global arena. The knowledge gained from this work will aid the research team in effectively identifying stratigraphic sequences in the USA and in overseas for future potential sequestration and energy storage sites.