This research examines the health effects of two pesticides: profenofos and mancozeb, focusing on their biological mechanisms of toxicity. Our lab group identified profenofos and mancozeb as two of the most widely used pesticides in Rwanda, despite profenofos no longer being registered for use in the US, and mancozeb being banned in the EU due to its known health effects. We have conducted a literature review centered on profenofos and mancozeb, with additional research into related pesticide classes: organophosphate insecticides and ethylene bis-dithiocarbamate fungicides. The literature review drew on scientific articles from PubMed, Google Scholar, and ScienceDirect, as well as government documents such as EPA reports and publications from individual states and the US Department of Agriculture, international agencies, and toxicology databases describing the acute and chronic health impacts of pesticides. Profenofos, a neurotoxic insecticide, has been linked to short-term symptoms including miosis, urination, diarrhea, diaphoresis, lacrimation, central nervous system excitation, and salivation, as well as long-term risks such as neurological damage and endocrine disruption. Mancozeb, a fungicide, has been linked to short-term symptoms including skin irritation, coughing, sneezing, sore throat, and bronchitis, and long-term risks including thyroid dysfunction, reproductive toxicity, and neurotoxicity. This research is important because farmers in places like Rwanda often use pesticides that are banned or restricted in other countries without access to proper training or protective equipment, increasing their risk of exposure. Understanding the toxic profiles of these pesticides can help design interventions that reduce poisoning events and protect people who are exposed to them.

DNA is a crucial component of forensic science analysis, and its degradation can impact the reliability and accuracy of forensic results. This study investigates how different textile materials and environmental conditions influence DNA degradation and the efficiency of DNA extraction from blood stains. By understanding the limitations of DNA, forensic scientists can understand the limitations of their own analysis. 500 µl of swine blood will be placed on different textiles (faux leather, wool, polyester, and cotton) and left in varying environmental conditions for a set number of hours. These conditions are meant to represent real-world forensic scenarios. DNA extraction and quantification will be performed at designated time intervals to assess degradation rates and the effectiveness of extraction. Each sample will be prepared by cutting a 1 cm² square of stained fabric and placing the fabric in a microcentrifuge tube. Extraction of DNA will be conducted following a phenol-chloroform protocol. The analysis of DNA quality will be measured using Agarose Gel Electrophoresis and Nanodrop. Different textile materials and environmental conditions will significantly affect the rate of DNA degradation in bloodstains with natural fibers exhibiting higher degradation rates under harsher environmental conditions compared to synthetic fibers.

Opioid addiction is an epidemic with U.S. fentanyl overdose death rates escalating. Addiction is a chronic brain disorder marked by compulsive drug use and a pervasive vulnerability to relapse. The Nucleus Accumbens (NAc) brain region is the central hub for reward circuitry and plays a key role in driving addictive behaviors. In the NAc, Parvalbumin Interneurons (PV) strongly inhibit medium spiny neurons (MSN); these sparsely expressed neurons have been suggested to help control how the local brain circuits work during reward-seeking behavior. Using fiber photometry, we tested whether PV interneurons in the NAc respond to fentanyl-associated cues during intravenous self-administration (IVSA). PV-2A-Cre mice were injected with GCaMP, a calcium indicator, and implanted with fiber optic cannulas. After receiving IV catheters, mice underwent IVSA training. Neural activity was recorded across four phases: acquisition (lever learning), intermittent access (alternating drug availability), progressive ratio (measuring motivation), and reinstatement (drug- and cue-induced relapse). During drug-available sessions, PV activity increased after active lever presses (p < 0.01). When the houselight signaled drug unavailability, PV activity also rose (p < 0.001), but not when the light turned off to indicate drug access. In the progressive ratio phase, PV activity was elevated during rewarded lever presses (p < 0.001). In reinstatement, both cue exposure and lever pressing increased PV activity. These results suggest PV interneurons become more active regardless of fentanyl presence, indicating a role in drug-seeking behavior. Future studies will use dual-color photometry to explore how PV activity influences MSN responses in the NAc circuit.

Caenorhabditis elegans are free-living nematodes that use olfactory cues to navigate their environment (chemotaxis). One chemical that triggers chemotaxis in C. elegans is benzaldehyde. Benzaldehyde is a food additive that has an almond-like odor. When exposed to benzaldehyde in various dilutions for a short time, the worms display attractive behavior. Moreover, prolonged exposure to benzaldehyde causes an increase in attractive behaviors to be passed down through multiple generations. Studies have shown that exposing C. elegans to benzaldehyde at various dilutions for 5 consecutive generations is enough to continue to show enhanced attractive behavior for 40 generations. However, C. elegans exposed to undiluted concentrations of benzaldehyde display avoidant behavior.The literature has not fully explored whether undiluted benzaldehyde causes the inheritance of avoidant behavior and if it can be passed down to multiple generations, similarly to attractive behaviors. My study will look to understand how the timing of exposure within early development determines the strength/ duration of inheritance of avoidance behaviors. I believe that worms exposed to benzaldehyde in high concentrations during early development will pass avoidant behavior to more generations, and the effects will be stronger, lasting more than 40 generations. I aim to understand when avoidant behavior occurs, what neurons are active when behavior is switched to stable inherited avoidant behavior, and what signaling pathways are affected. Because C. elegans shares similar conserved genes, signaling pathways, and neuronal circuitry as humans, this research should provide a solid foundation for my future research endeavors.