Daphnia magna are freshwater microcrustaceans used for toxicological and water quality studies. The straightforward study of the organism’s motor and swimming behavior makes it a valuable specimen to study neurochemical effects. Daphnia locomotion was observed under the effects of Manganese (II) Chloride. Manganese is an abundant element and in prolonged exposure, can result in a neurological condition called manganism. This condition causes movement and cognitive deficits like those seen in Parkinson’s disease. To build upon previous research, Daphnia were also rescued from post-manganese toxicity using P7C3-A20. P7C3-A20 is a small neuroprotective molecule discovered to promote neurogenesis by preventing premature neuronal cell death. Daphnia were treated with manganese concentrations between 0.0-100.0 mg/L. This range includes the previously determined IC50 at 43.1mg/L. At the 24-hour time point, the animals were imaged and then treated with P7C3-A20. Locomotion was also imaged at 48 and 72 hours after manganese treatment. Tracking was accomplished using CTRAX, a two-dimensional imaging tool. Data from CTRAX was analyzed using MATLAB, a programming software, and then plotted in Excel. Our working hypothesis is that P7C3-A20 treatment after manganese exposure will result in an improvement in the motor behavior of Daphnia compared to Daphnia that were treated with manganese alone.

Sepsis is the number one cause of deaths in hospitals in the United States. Currently it is not known which antibiotic is the best to treat Sepsis. Outer-membrane vesicles (OMVs) are believed to be linked to Sepsis, so the antibiotics used to treat Sepsis should have the lowest number of OMVs released. Nine different antibiotics from three different families were used to treat Escherichia coli. Following this the samples were concentrated and purified using a centrifuge and ultracentrifuge to isolate the OMVs which were then quantified using western blots and nanoparticle tracking analysis. The results found that beta lactams release the most OMVs, while aminoglycosides and quinolones release significantly less. These results will help in the treatment of Sepsis and save lives.

Determining a more resource-efficient way to provide plants with the nitrogen they require for proper growth would minimize the damaging overuse of nitrogen-based fertilizers and serve as an excellent trait for biofuel crops that are intended to grow in less-than-ideal soil and with as minimal inputs as possible. One possible way to increase nitrogen absorption efficiency includes artificially selecting the microbiome of the plant via a stress that induces symbiotic bacteria to fix more nitrogen. The plant root microbiome is known to provide numerous benefits to its host, including known microbes that fix nitrogen for the plant to use, but the interactions that take place in these communities is largely unknown, often leading the benefits of individual microbes to become muted once they are placed in a community. In an effort to study microbe-microbe interactions and determine if artificial microbiome selection can be used to create more nitrogen-efficient symbiotic relationships, we will place brachypodium distachyon with a known synthetic community of microbes under nitrogen stress and transfer the microbial result over multiple generations. We will also include an engineered nitrogen-fixing strain that overproduces nitrogen at the expense of being a weak strain to determine if this strain can be integrated into a microbe community and if microbe-microbe interactions can aid this weak bacteria. Preliminary experiments will focus on testing the engineered bacteria, including whether it can successfully propagate in a known community and whether it prefers one plant host over another, as well as determining which nitrogen stress to select the microbiome on.

Large scale restoration is currently underway in the San Francisco Estuary and seeks to increase shallow nursery habitat for several imperiled fish species. These projects cost millions of dollars but highly dynamic tides obscure efforts to measure their intended impact. For example, shallow water provides critical refuge and rearing functions for wetland-associated fishes, but enumerating this feature requires one to integrate depth over a range of tidal timescales. We seek to address this challenge by developing a tidally variable habitat model which incorporates water surface elevation, land surface elevation, and fish depth thresholds. This tool is intended to help elucidate the wetland landform features which engender desirable habitat resources for Chinook Salmon smolts in San Francisco Bay Delta.