Presentation of Honors Theses, Group A

Bisphenol-A (BPA) is a structural component in many plastic products, which acts as an endocrine-disruptor mimicking estrogen. This hormonal disruption has been linked to obesity, reproductive issues, cardiovascular problems, and neurodevelopment disorders. Infants are at the highest risk of BPA exposure compared to any other stage of life. Because an infant's endocrine system is developing, exposure to an endocrine-disruptor, such as BPA, can be especially harmful. While the FDA monitors products like baby bottles, canned goods, and plastic containers for BPA, infant oral hygiene products are not closely monitored.

Previous research in our lab used fluorescence spectroscopy to test several brands of infant toothbrushes and found that many contain and leach BPA into their surroundings. Bisphenol-A fluoresces at an excitation wavelength of 278 nm and an emission wavelength of 304 nm. When tested at the average body temperature, 37 °C, research showed an increased amount of BPA leaching from the toothbrushes. For this project, toothbrushes were tested by storing them at higher temperatures, 50 °C, prior to testing for time increments similar to that of shipment in semi-trucks. Large shipments spend an average of 3-7 days in semi-truck containers, and the shipment temperature, on average, reaches 50 °C. Toothbrushes were then placed in 1: 1 methanol/water for several hours. Aliquots were removed over time, and the amount of BPA leaching from the samples was monitored using an FS5 Spectrofluorometer from Edinburgh instruments. The results of this experiment revealed an insignificant increase in the amount of BPA leaching out of toothbrushes at increased duration and temperature.

Drug inclusion in fiber mats is an important aspect of modern wound dressings for healing assistance. Through the infusion of drug molecules in modern bandages, dressings can be loaded with compounds that fight infection and hasten the healing process. Therapeutics are typically infused into nanofibrous mats via electrospinning a solution of a polymer mixed with a drug molecule. While this technique is an effective means of incorporating drugs into constructs, it limits the application of the resulting mats to conditions that call for that specific therapeutic. Alternatively, dipping polymer nanofiber mats into therapeutic-containing solutions is another way drugs could be infused into materials that could prove to be an alternate and more accessible infusion method. The objective of this research is to compare the drug release from electrospun nanofiber mats using two different methods of infusion: dipping and electrospinning. The hypothesis of these preliminary studies is that therapeutic-dipped fiber mats will give a similar drug release profile to that of therapeutic­electrospun fiber mats proving the dipping method of drug infusion can be an equitable and flexible alternative to. the current electrospining method of infusing drugs.

Audiologists play a major role in helping people with hearing loss learn how to better communicate and how to connect to the world around them. The purpose of this project investigates the extent to which audiologists counsel their clients for the psychosocial stress factors caused by hearing loss, along with determining the extent in which patients with hearing loss feel they would benefit from counseling services implemented into their appointments. In addition to psychosocial stress factors, the thesis will analyze the extent to which clients are educated on their hearing loss and given practical ways to adjust to their loss based on their individual lifestyle. The study will analyze the main reasons why people do not seek consistent audiology counseling when diagnosed with a hearing loss that can potentially disrupt daily routines and/or cause emotional distress while trying to adjust to the change in their hearing status. Additionally, the project will compare responses from those with hearing loss to the responses regarding audiologists' perceptions, extent of training, and confidence level of counseling patients beyond completing a hearing test and programming amplification devices.

Preliminary findings based on the results of 52 completed surveys from those with hearing loss (clients) and 42 completed surveys from audiologists indicated positive correlation between the client's experience and the services provided by the audiologist. The majority of the responses about the education and adjustment strategies for hearing loss were consistent between the two groups. In regard to the counseling component, clients reported they did not feel they receive adequate counseling from the audiologist, and the audiologists indicated they did not receive adequate training in counseling.

Experiments have shown that objects with uneven surfaces, such as golf balls, can have less drag than those with smooth surfaces. Since fractal surfaces appear naturally in other areas, it must be asked if they can produce less drag than a traditional surface and save energy. Little or no research as been conducted so far on this question. The purpose of this project is to see if fractal geometry can improve boat hull design by producing a hull with low friction.

Antibiotics will not be used forever by society due to antibiotic resistance. By the year 2050, it is predicted to have caused millions of casualties throughout the world. Thankfully, bacteriophages and phage therapy could be a potential solution to this problem.

Rock Sandpipers (Calidris ptilocnemis) are a shorebird species only found in the North Pacific Basin (Ruthrauff, et al. 2019; Fig. 1, 2). There are four subspecies of Rock Sandpipers, C. p. couesi, C. p. quarta, C. p. tschuktschorum, and C. p. Ptilocnemis (Gibson & Withrow, 2015). Of these four subspecies, three have an overall conservation category of moderately high with a current unknown status and high biological vulnerability due to environmental disturbances (ACCS at UAA, 2018). The three subspecies compared for differences in their genetic diversity and population relatedness were C.p. couesi, C.p. tschuktschorum, and C.p. ptilocnemis. The subspecies differed in their primary migratory and breeding locations: C.p. couesi is found in the Aleutian Islands, C.p. tschuktschorum is found on the Seward Peninsula and Cold Bay, and C.p. ptilocnemis is found on the Pribilof Islands. The subspecies are further distinguished through their morphological differences among populations. C.p. ptilocnemis is of the greatest conservation size due to the differing population size of its two island populations.

Cancer uses intercellular communication to induce tumor growth and metastasis. Fibroblasts can become specifically transformed and associated with cancer to aid in the process. Extracellular vesicles, specifically exosomes, contain proteins, RNA, and DNA that are taken up by local cells to affect cellular behavior. Exosomes were isolated from lung carcinoma using total exosome isolation reagent and quantified. These exosomes were used to treat lung fibroblasts and enrich lung carcinoma cells, and the effects of exosomes on cancerous properties, cell viability and cell migration, were studied. An increase of cell viability was found with exosome treatment for both cell lines while migration only increased for enriched lung carcinoma cells. Additionally, mass spectrometry-based proteomics of exosomes isolated from hepatocellular carcinoma was analyzed. Through a survey of differentially expressed proteins between high and low grade hepatocellular carcinomas against normal liver cells, several pathways of interest were identified. Some common motifs in underexpressed genes were the regulations of cell signaling, cell metabolism, and cell death. A study of miRNAs in exosomes along with potential theraputic exosome uses was performed.