Bismuth nanoparticle (Bi NPs) have wide-ranging applications in both biomedical imaging and nanotechnology. These applications are hampered by the absence of a sized-controlled, uniform synthesis using conventional laboratory techniques. The current synthesis of such particles is arduous and requires specialized techniques and equipment, specifically air-free techniques, which are not readily available to all. By using air stable and cost effective reactants, we hope to develop and characterize a synthesis that is reliable, aerobic, free of lithium based organic bases, and potentially offers size control between 30 nm and 70 nm. This synthesis would produce high quality Bi NPs that are available to a wider range of researchers.

Eclipsing binaries (EBs) are systems in which two stars orbit and pass in front of each other. They are important astrophysical tools utilized in this project to directly measure the fundamental properties of stars, such as their masses, and radii. We create a sample of ~50 bright EB targets based on high-quality photometry from the Kepler Satellite and spectroscopy from the Apache Point Observatory Galactic Evolution Experiment (APOGEE). Here, we present mass, radius, and orbital solutions for a subset of these EBs. For each system, we extract radial velocities (RVs), the speed at which each star in the system is moving away from the observer, from the APOGEE spectra. Then, we combine the RV with Kepler light curve (LC) information to simultaneously model the system light and line-of-sight speed as a function of time. Because our model has high dimensions with 18 free parameters, we first solve for the LC and RV solutions separately, and then simultaneously solve them. We use a least-squares optimization method to determine the best fit solution and quantify the uncertainties in model parameters running Monte Carlo Markov Chain (MCMC) simulations. The model parameters that we find will further our understanding of fundamental stellar properties and evolution.

Influenza is a viral respiratory tract infection responsible for 15-60 million infections and more than 200,000 flu related hospitalizations in the United States annually. Diagnostics can help stop outbreaks and treat infections, however the current flu detection methods lack high sensitivity. The Yager Lab at the University of Washington is developing a simple diagnostic test to identify subtypes of the influenza virus. The assay targets the viral surface protein hemagglutinin (HA) and can specifically detect two strains of the influenza virus, the Solomon Islands strain of H1N1 and the Switzerland strain of H3N2. We have developed an automated device for this assay, supplying the reagents sequentially using a pinched valve and water soluble paper. I have tested and modified this device in order to enable hands free operation once the sample (a nasal swab) is inserted in the system. The paper based assay is fast, specific, and easy to use, allowing rapid diagnosis of influenza in any setting.

Callous-Unemotional (CU) traits, a component of psychological conditions that demonstrate conducts of insensitivity and a lack of empathy and remorse, consistently forecast severe antisocial behaviors and correlate with insufficiencies in recognizing emotions. Attention-Deficit Hyperactivity Disorder (ADHD) is linked to impairment in social functioning & misinterpretation of social cues. Facial Emotion Recognition (FER) or the ability to understand how facial expressions correspond to an emotion is linked to empathy and emotional development. This study will examine if students high on symptoms of ADHD related behaviors exhibit higher levels of CU traits and lower FER than peers low on ADHD related behaviors and gender differences. Results suggested that there was no correlation between ADHD related behaviors and CU traits but there was a statistically negative correlation between FER and ADHD. Analysis suggests that FER differences are only present for students high in ADHD related behaviors. Lastly, a significant negative relation was found between CU traits, gender, and ethnicity. Analysis suggests that males and ethnic minority students had higher levels of CU traits. Implications of the current findings are discussed.

Ambisonics is an audio technique that allows for precise production, manipulation, and playback of full sphere surround sound. For the most part this method has been limited to academic circles, but recent advances in computing, software, and Virtual Reality (VR) have made Ambisonics more accessible and applicable than ever before. Although these developments are exciting, the amount of effects designed for this audio methodology is minuscule in comparison to traditional audio environments. The purpose of this project is to explore the Ambisonic implementation of traditional digital audio effects by creating an Ambisonic reverberator. To clarify, a reverberator is a structure that uses echoes to simulate the reflections of a 3D space. This effect was chosen as the focal point of this study because there is a significant amount of literature regarding its development in an Ambisonic context. Research proceedings consisted of an initial proposal, creating a testing algorithm, building a monophonic reverberator, and converting this architecture to Ambisonics. The final algorithm is comprised of a delay-line cascade that is fed back into itself forming a feedback loop. Inside this loop, the summation of these delays is transformed in space over time to create a rich three dimensional spatial image. Further exploration of the methods presented could lead to detailed three dimensional room modeling, proximity effects for VR, and Ambisonic adaptations of other digital audio effects.

Financial inclusion - the expansion of access to formal bank accounts, particularly to the poor - has recently moved up the ranks as a priority for development. After the unexpected success of M-PESA - a mobile phone based money transfer service started in Kenya - many quickly joined the camp of mobile money advocates believing that mobile money would be the solution to this newly minted UN sustainable development goal. However, with such nuanced characteristics in each country and even more distinctions within each financial system and economy, mobile money as a solution may not be applicable in every country aiming for financial inclusion. Therefore, this research aims to primarily understand the financial practices and needs of Ghanaians. To do so, I conduct surveys in five different cities ranging from small towns to large cities to evaluate an individuals current financial practices, existing and projected needs for financial services, and the role that mobile money may play in fulfilling either of those goals. 

Chronic pain is a widespread health concern affecting over 100 million Americans nationwide and interfering with all aspects of a person’s quality of life. The Chronic Pain Self-Management Program (CPSMP) is a self-management training model involving a six-week long workshop designed for adults with chronic pain conditions to gain the knowledge and skills to manage chronic pain. The CPSMP has been adapted from Stanford’s well-researched Chronic Disease Self-Management Program (CDSMP) which was found to improve many areas of participants’ health status, health care utilization, self-efficacy and self-management behaviors for chronic diseases. However, little to no evidence exists on the program effects for people with chronic pain conditions, leaving the question as to whether CPSMP workshops effectively enable participants to better manage their own health and improve their overall quality of life. The purpose of this study is to assess how effective CPSMP workshops are at improving participants’ self-efficacy in managing their pain and overall health status. This study reports on the results of six CPSMP workshops held between October 2015- March 2017 that were offered through Harborview Medical Center (HMC) in partnership with African American Reach and Teach Health (AARTH). Participants in these courses completed pre and post surveys including questions from the PROMIS Scale v1.2 – Global Health, UW Pain Tracker, PHQ-4, and the Perceived Confidence Scale (PCS) to evaluate the experience of pain of each participant, the extent to which their pain limits their daily activities, usage of pharmaceutical pain management methods, and overall usage of medical care before and after their participation in the HMC CPSMP workshops. If the results of this study reveal positive improvements in participants’ confidence in their ability to manage their chronic pain conditions, further research may be done to identify the sustainability and long term outcomes of CPSMP programs.

The proposed study will explore the relationship between temperament and child psychological adjustment in a sample of children during their first year after cancer diagnosis (N = 160, ages 2-18). Multilevel growth modeling will evaluate the longitudinal relationship between three dimensions of temperament (effortful control, extraversion/surgency, negative affect) and trajectories of two psychological adjustment variables (externalizing problems, anxiety/depression scores) across twelve time points. While the primary goal of this study is exploratory, we offer the following predictive hypotheses: (a) psychological adjustment will improve over the course of treatment; (b) negative affect will be associated with higher anxiety/depression and lower externalizing problems; (c) effortful control will be associated with lower externalizing problems; (d) extraversion/surgency will be associated with lower anxiety/depression and higher externalizing problems. The proposed study has numerous advantages over comparable studies in this area of research, such as its relatively large sample size, longitudinal structure with a large number of time points, and measurement of temperament across three specific dimensions. Findings from this study may help health care providers anticipate and mitigate negative psychological outcomes in pediatric cancer patients. Additionally, the findings may inspire future research directions involving temperament and other outcome variables, such as health-related quality of life and family adjustment.

My research focuses on how inspiration porn articles perpetuate the Medical Model of Disability, and specifically, on how those articles objectify and devalue people with Down syndrome. Inspiration porn refers to the representation of disability as a form of disadvantage that can be overcome; it often celebrates disabled people simply for living with a disability. This “overcoming” narrative stems from the Medical Model of Disability, which defines disability as an individual defect and personal tragedy. While many Americans have not heard the specific term “inspiration porn,” most have been exposed to inspiration porn articles. I conducted a qualitative content analysis to explore my research aim; this methodology allows for the investigation of the underlying, context-dependent meanings of a text. My unit of analysis was individual articles. I identified these articles through use of the search engine Access World News. These articles have been published in the USA between the dates of 1/1/16 and 12/31/16, and have the words “Down syndrome,” “Down’s syndrome,” “Downs’ Syndrome,” or “Downs Syndrome” in the headline. After I created my coding frame, I analyzed every 10th article, and then interpreted the findings to ascertain the prevalence of inspiration porn, and how inspiration porn perpetuates the Medical Model of Disability. I initially anticipated the results of my content analysis would indicate that inspiration porn articles, in perpetuating the Medical Model, reinforce limiting and unrealistic stereotypes of people with Down syndrome. This result would show how the growing popularity of inspiration porn is troubling. This new phenomenon does not promote inclusion and diversity – rather it encourages interactions between those with disabilities and those without, in a superficial, condescending manner. My research is important because it draws attention to disability as a sociological topic, and further expands upon media studies by examining the role of mainstream media in perpetuating stereotypes.

Females use many different sanitation products, including tampons and pads. However, it is speculated that some of these everyday products for some women may contain heavy metals and other chemicals. Lead is a heavy metal that presents a danger as can cause cancer and mental inefficiencies. Chromium is said to cause dermatitis and skin irritation. These metals are often thought of to be threatening in water and soil. However, man-made products such as tampons and sanitary napkins/pads can contain these heavy metals. Using standards from both metals and ICP technology, or an Inductively Coupled Plasma machine, analyzed the feminine hygiene products for chromium and lead. In my analysis of the hygiene products there does not seem to be a concerning amount of heavy metals, even with an increased mass analyzed. Very small amounts of chromium and lead were found in both pads and tampons. There appeared to be more lead than chromium in tampons, yet not a large amount to report stark differences.

SUMO (small ubiquitin-like modifier) is a protein post-translational modification that has wide ranging influence on protein function. Among its many roles, SUMO is known to regulate transcription, DNA repair, and maintain cellular homeostasis under environmental stress conditions. Changes in sumoylation patterns under environmental stress have been identified, yet the specifics of these pathways remain uncharacterized. By using mass spectrometry (MS), we have identified three yeast proteins that are sumoylated in response to high levels of ethanol: Top2, Smc5, and Smc6. These proteins play a major role in maintaining DNA stability during replication and are conserved through higher eukaryotes. We have tagged these proteins with epitopes identifiable by western blot by yeast transformation, and subjected cells with these tags to ethanol stress, which allowed us to verify the hits from the MS screen. This will allow us to begin further investigation of the role sumoylation plays on these proteins. Our next goals include generating sumo deficient mutants and observing the changes in protein function within the cell after exposure to ethanol stress. As these proteins are involved in DNA stability and repair, we are notably interested in the interactions with chromatin. Through this work, we seek to gain us a better understanding of the signaling underlying adaptation to environmental stress. This research has implications for human health as it allows us to understand how cells respond to toxic levels of a recreationally encountered substance.

In July of 2016, I was a part of the exploration seminar: ‘Global Health Promotion: Health Services Delivery in Resource-poor Settings’ led by Professor Mabel Ezeonwu, where students spent two weeks in Guatemala. While conducting research in six rural villages in Guatemala, my team, Briana Hermes, MyKa’La Alexander and I asked the question “what are the gender roles for women, especially within a healthcare setting?” We worked from feminist theory which argues that gender is a social construction where gender norms are created, performed, and normalized. As researchers, we conducted participant observation through observing the patients receiving health assessments through the clinics we set up. Our participation included delivering basic health care provisions as well as hygiene and dental education. As we worked alongside and within the communities, we observed women’s and men’s roles in an attempt to further understand the daily expectations and responsibilities of women in the villages. We also conducted research, looking for trends and patterns in women’s expected roles while in a health care setting. Here, we found women to be timid while explaining symptoms in addition to refusing some medical services. Through our research, we conclude that Guatemalan women in these six communities are still limited by “traditional” gender expectations. This includes being caretaker of the children, cooking and cleaning which position women’s roles and social status as subordinate to men. Our research raises awareness of gender inequities that are in cultures all around the world, necessary to create a more conscious and positive change in our own society.

The structure of plastid DNA (ptDNA) provides insight concerning its replication, repair, maintenance, and stability. We are studying DNA molecules and their association with proteins in plastid nucleoids as maize seedlings develop from the newest cells in the basal meristem to the oldest in the leaf tip. When observing unbound ptDNA from light-grown seedlings, we have found that ptDNA copy number and molecular integrity decline from complex-branched forms (Type I) in the meristem, to a mixture of smaller complex and simple forms (Type II) in the stalk, and small simple forms (Type III) in the leaf blade. In contrast, preliminary examination of unbound stalk ptDNA showed that for the dark-grown seedlings ptDNA is maintained at high copy numbers, with large complex forms. Furthermore, DNA fibers connected to these complexes were longer in dark-grown than light-grown stalk. We will now continue to examine unbound ptDNA in the meristem and leaf blade from dark-grown seedlings. Once finished examining all samples of unbound dark-grown ptDNA, we will analyze nucleoid-associated ptDNA and deproteinized ptDNA of dark- and light-grown seedlings by gel electrophoresis and fluorescence microscopy. For the basal meristem of light- and dark-grown seedlings, in nucleoid-associated ptDNA, we expect similar high-integrity Type I ptDNA, since this is where replication is highest. In contrast, we expect major structural differences in the nucleoid-associated leaf blade ptDNA, with small Type III in light-grown and high-integrity complex Type I forms in dark-grown plants. We propose that replication and repair occurs exclusively on nucleoid-associated ptDNA and that unbound ptDNA is susceptible to nuclease degradation. Therefore, we expect complex forms for nucleoid-associated ptDNA and small, degraded molecules for the non-nucleoid fraction. On a larger scale, this research will be important for genetically modifying maize tissue, because we will know more about the structural integrity of the DNA we are targeting.

Giardiasis is a disease caused by the protozoan parasite Giardia lamblia which affects approximately 20,000 people per year in the United States alone. To this day, there are few anti-Giardiasis drugs available so new therapeutics to address toxicity and resistance issues are needed. In previous studies, we have examined seven protein kinases in Giardia’s genome and these kinases share an unusual structural feature in their active site, which results from an atypically small gatekeeper residue (amino acid residue). This feature confers sensitivity to a class of compounds called bumped kinase inhibitors (BKIs); BKIs demonstrated minimal toxicity and positive pharmacological properties. We repeated the search for small gatekeeper kinases using an updated multisequence alignment program, which identified four new small gatekeeper kinases. We developed a cloning strategy to 3HA tag each of these kinases. Then, we evaluated the expression and cellular localization of the proteins using Western blot and immunofluorescence (IF) assays. With the tagged kinase lines, we utilized translation blocking morpholinos to test the importance of each kinase using cell growth. This data will be used to prioritize protein purification for screening against a BKI library using thermal shift assays. These results may identify lead compounds toward novel treatment options for giardiasis.

The ability to recapitulate the dynamic presentation of signals in a stem cell’s microenvironment remains a major hurdle in tissue engineering. By controlling cell growth and differentiation in 4 dimensions (i.e., time and 3D space) heterogeneous synthetic tissues could be produced that match the complexity of their native counterparts. Combining strategies in both light-programmable hydrogels and recombinant protein engineering, we control the cellular microenvironment. Previously, we have demonstrated the ability to photopattern gels with fluorescent proteins by introducing a biorthogonal synthetic handle site-specifically modified onto our proteins via the sortase enzyme, and a photocaged reactive group in the hydrogrels. The photocaged group uncages upon UV light exposure, allowing for a reaction to occur and a covalent bond to form between the synthetic handle and the hydrogel. While covalent interactions form strong bonds, they are generally irreversible using mild, cytocompatible chemistries. In addition, this technique uses UV light, which may be harmful to cells. By incorporating LOVTRAP into the photopatterning system, we introduce a greater amount of control by allowing for full reversibility. In the dark, LOV2 and Zdk1 dimerize to form a protein-protein bond with similar stability to an antibody-antigen interaction. Upon exposure to blue light, the dimer dissociates, allowing for fully reversible control over conjugation. The Zdk1 domain can be incorporated into a protein of interest using genetic engineering, while still maintaining its binding affinity for LOV2. LOV2 can then be conjugated throughout a hydrogel to make a light responsive protein binding material. By utilizing a light controlled dimerization event between proteins, the LOVTRAP system is fully reversible using only blue light. This technique could be used for tissue engineering applications that require mild treatment conditions and full dynamic control over the presentation of biochemical cues.

Mosquitoes transmit diseases that affect millions of people each year. As such, there is an urgent need to explore every avenue to develop efficient tools to control them. In this context, my project aims to better understand their host-seeking behavior by exploring how visual and olfactory stimuli affect the mosquito’s flight response. In the Zika and yellow fever vector, Aedes aegypti, exposure to CO₂ triggers a strong attraction to visual features. However, the temporal and spatial features of this olfactory-gated visual response are still unknown. For my project, I seek to dive deeper into the characterization of this phenomenon. Specifically, I am interested in determining how long the effect of CO₂ lasts, and to what extent this effect is a function of the size and shape of the visual stimulus. To investigate these factors, I utilized a flight LED arena in which a tethered mosquito was presented visual stimuli and CO₂ pulses delivered at different time intervals. I recorded wingbeat frequency and amplitude, torque, head angle, and leg movements while producing 16 distinct sensory scenarios in which the size of the visual stimulus, and the timing between the delivery of pulses of CO₂ and the visual stimulus were manipulated. From this dataset, I will be able to extract the fine scale behavioral flight response to these unique sensory combinations, deepening our understanding of the complex interplay between visual and olfactory stimuli in mosquito host-seeking behavior. These results bear the potential to lead to the improvement of mosquito control strategies that target their behavioral responses to visual and olfactory stimuli.

Most organisms show a roughly 24-hour cycle in their physiological and behavioral processes, called circadian rhythms. Circadian rhythms are generated endogenously through the ~24-hour cyclic expression of genes known as clock genes. The expression of these genes oscillates in the master circadian clock of mammals – the suprachiasmatic nucleus (SCN) - but also in nearly every cell of the body. Typically, circadian clocks and the rhythms they sustain are ‘entrained’ by the 24-hour light-dark (LD) cycle. Our lab has found that fear can also act as an entraining factor; we observed that mice and rats subjected to random foot shocks during the dark phase of the LD cycle in their cages’ foraging area changed from their typically nocturnal foraging pattern to a diurnal one, avoiding the fear stimulus presented during the dark. The goal of my project is to understand the neural circuits and molecular processes that are involved in fear entrainment. I have analyzed the expression of clock genes in animals that are exposed to nighttime fear or in control animals exposed to daytime fear, using a technique called in situ hybridization, which labels mRNA levels. This allowed me to assess the circadian rhythm of expression of clock genes of interest (Per1 and Bmal1) in the SCN and the amygdala, the region of the mammalian brain that encodes fear stimuli. Our findings could not only help elucidate the circuits that are involved in fear entrainment but also help understand the mechanisms that link fear and anxiety disorders to problems with circadian rhythms and sleep.

The North Atlantic right whale (Eubalaena glacialis, NARW) is among the most depleted species of whale existing today, with a current estimated population of only 450. Ship strikes and entanglement issues remain the predominant cause of mortality for this critically endangered species. Thus, understanding NARW distributions, and their overlap with human activities, are a top priority for management and conservation efforts. This study analyzed passive acoustic data collected within the migratory corridor from Cape Hatteras, NC to Brunswick, GA from Oct 2015 - June 2016 as part of a comprehensive seasonal distribution look at NARWs along the Western North Atlantic coast. Four lines of 5-8 Marine Autonomous Recording Units were deployed, stretching across the shelf, in the first deployment of a three year, continuous acoustic monitoring effort. These units were processed using the Low Frequency Detection and Classification System (LFDCS), and detections were screened for daily NARW presence. The results of this study show seasonal movements to and from their calving grounds while passing through Georgia, South Carolina, and North Carolina. Off the coast of Georgia and North Carolina, NARWs are detected primarily on inshore recorders from November to March, suggesting the species take paths closer to shore while migrating. However, in late April, the groups travelling north take a path further away from the Cape Hatteras, NC shore. NARWs were picked up predominantly on inshore recorders throughout all four lines of MARUs, further supporting that critical habitats exist close to the coast in southern US waters. This information provides a better understanding as to where NARWs are spatially and temporally located, which is essential in minimizing human impacts on the species.

 Deposits of methane sequestered along continental margins and their associated seeps are found worldwide. These seeps are of increasing interest and importance because of their potential as an energy source, their contribution to greenhouse gases, and the unique community of chemosynthetic microorganisms and fauna that they host. One of the bestudied methane seep sites is Southern Hydrate Ridge, which is at a water depth of ~800 m. It is located ~90 km west of Newport, Oregon. Despite extensive geophysical and biological research completed here, no studies have quantified the relationship of seep sites and seafloor geology to the spatial distribution and abundances of microbial and macrofaunal communities. High resolution, georeferenced photomosaics of the individual seeps and the associated biological communities at this site were collected in 2011, using the remotely operated vehicle ROPOS. Detailed visual and spatial analyses of these images has allowed for the quantification and characterization of the diversity and structure of the faunal community. Results show that both the distribution and abundances of seep organisms are highly variable. Further examination of these photomosaics may improve understanding of the relationships between faunal distributions and seep locations, with implications for the impacts that chemical gradients have on these ecosystems

Olympic mudminnow (Novumbra hubbsi), Washington’s only endemic fish species, was listed as “Sensitive” at the state level in 1999. However, limited knowledge and understanding has stalled conservation efforts. This study investigates the impact of invasive fishes on Olympic mudminnnow, focusing on Lake Ozette in Olympic National Park. Using stable isotopes from the species present in Lake Ozette, the trophic ecology of mudminnow was determined. Stable isotopes are naturally occurring and can be used to trace the pathways of aquatic- and terrestrial-derived energy and carbon transfer in aquatic ecosystems. This analysis method investigates carbon (¹³C, ¹²C) and nitrogen (¹⁵N, ¹⁴N) found within samples. The presence of these isotopes depends on what a species eats. Moving up the food chain, the ratios of ¹³C/¹²C and ¹⁵N/¹⁴N increase, identifying a species’ feeding position within a community. The higher the trophic position, the more ¹³C and more ¹⁵N will be present in the sample. Through analysis of the entire community, including fish, invertebrates, and plants, a generalized food web was constructed for Lake Ozette. Using linear models and a permutation method, the fish species were compared to the model to test for statistically significant differences between the measured ratio of carbon to nitrogen. If the position of the fish species was significantly different from the model prediction, then there is no niche overlap and competition is unlikely. The combined results of the stable isotope and spatial overlap analyses indicated which species impact Olympic mudminnow within Lake Ozette. This study provided key information concerning complex predator-prey interactions, which must be understood to manage Olympic mudminnow as well as the invasive species present in Lake Ozette. Since there is little known concerning this species, there are many opportunities to extend the knowledge base continuing both with the predator prey interactions and with other knowledge gaps.

Many 2 dimensional materials, such as Tungsten Diselenide (WSe₂) have many interesting device applications such as thin and flexible photo detectors and transistors. We use a process called chemical vapor deposition, which involves depositing a vapor of WSe₂ on a substrate by a specific application of heat. Specifically, we installed a secondary heating coil in our furnace which allows for a region of uniform temperature near the substrate. This modification allows for large scale growth of single crystals on the substrate. This approach to manufacturing has the advantage of allowing more samples to be studied and inevitably being more applicable to industrial applications. To determine if this method is feasible, we probe the quality of these crystals by measuring their electrical properties.

As of 2015, approximately 36.7 million people worldwide are living with HIV/AIDS, of which almost 15 million receive antiretroviral therapy (ART). These patients require regular HIV-1 viral load (VL) tests to monitor ART effectiveness and compliance. However, the majority of affected people live in low-resource settings, where accurate diagnosis and disease monitoring through lab-based instrumentation systems, such as nucleic acid amplification tests (NAATs), are inaccessible. Thus, there is an increasing need for accurate, affordable HIV-1 VL tests at the point-of-care (POC). We have leveraged an electrokinetic separation and preconcentration technique, isotachophoresis, and an isothermal nucleic acid amplification method to develop a fully integrated POC NAAT for extraction, amplification, and detection of HIV-1 nucleic acids in whole blood. We have demonstrated the ability to extract these nucleic acids from human serum and quantify the nucleic acid amplification with fluorescent detection. The fluorescent read-out is correlated to the initial sample concentration, providing semi-quantitative VL information. Our device operates in a single step with limited equipment in 15 minutes, consequently cutting the time, cost, and complexity of NAATs for infectious disease diagnosis, especially in low-resource settings. Our POC NAAT has the potential to improve patient care, and we are currently investigating applying this technology to diagnose other infectious diseases.

Indigenismo, a central ideology in Mexico’s post-revolutionary nation-building projects, both celebrated and sought to assimilate Mexico’s substantial indigenous population. The ideology was shaped by several disciplines, including biology and anthropology, and was adopted by the Mexican government to promote cultural nationalism in the 1920's and 1930's. There was a common agreement that education reform would be key to spread multiculturalism which, in theory, would create a more holistic and established “Mexican” identity. While the architects of indigenismo were predominantly privileged mestizo men, the subjects of their efforts were primarily women, who bore the burden of reproduction and family education. Nonetheless, the scholarship on indigenismo in Mexico has yet to explore gender roles and eugenics. My project adopts a gendered lens to explore if and how these cross-culture teachings reshaped the societal expectations of womanhood among indigenous women. Using archival research, teaching pamphlets and publications by these policy makers along with secondary scholarship, I hypothesize that reformers used education to control the indigenous female body.

“This Is Our Story” project is a qualitative research project with a digital multimedia component. This project utilizes students and staff, from the Samuel E. Kelly Ethnic Cultural Center (ECC), to create a mix of timeless tradition of storytelling with digital media as a multimedia form of documenting individual histories. Currently, I have been conducting interviews in the Kelly ECC to learn stories about different lives of many students and staff at the University of Washington. I asked questions about themselves (personality, what defines you, what makes you, favorite food/activities, etc.), background, and traditions with family and friends, connections to the ECC. In the next two weeks, a media display will be created with the results from the interviews to provide an interactive way to share students’ experiences and backgrounds. Visitors and users of the Kelly ECC may interact with the project to hear and watch video clips to learn more about other members of their UW community. A key goal of this project is to create bridges between the intersections of our diverse identities. The second goal of this project is to showcase the uniqueness of the diverse people at the ECC. The display will demonstrate that we are all from different places, but in the same space, becoming allies with each other. This interactive system will allow people to educate themselves about cultures. Through this project, I hope to highlight the importance of oral storytelling, and hope to create a fun and interactive way to share personal histories in an age that is driven by social media.

For our research, we are focusing on dice and how we can relate them to voting systems. We want to see if we can create dice systems that mimic voting systems (with >2 candidates) and the traits that the systems possess. Two ideal traits of these voting systems are Pareto, which means that if everyone likes candidate A more than B, candidate B should lose; and IIA, which is if candidate A wins, then everyone mixes their ballot but keeps A's rank relative to B the same, then A should still win. However there is Arrow's Theorem, a central focus of our research, which states that if your system is Pareto and IIA, you must live in a dictatorship. One major topic of our research is trying to show whether or not this holds for our die systems. In order to accomplish this, we set out to define what these traits would be in terms of dice and how to translate dice outcomes to voter results, which we have successfully done for Pareto and IIA thus far. Our methods for this included testing certain systems that would reflect moving candidates/voters around, and testing these systems using some code we wrote for this purpose. Some other topics for our research are translating specific voting systems, such as popular vote, pairwise competitions, and point systems to dice, and showing whether or not these ideal traits hold for these translations, which we have successfully done for some. With this, we hope to gain a better understanding of these systems and how using something truly random, such as dice, has any reflection on the systems we have in place.

Conjugated linoleic acid (CLA), the only naturally-occurring trans-fat, is a fatty acid that is known to promote weight loss and increase energy expenditure. While it is considered a potential treatment for those struggling with weight-induced illness, previous research has shown its association with impaired glucose metabolism and inflammation. Using qRT-PCR to analyze expression of genes important for glucose metabolism and inflammation, we studied whether rosiglitazone, an insulin-sensitizing agent, improves CLA-mediated insulin resistance and adipose tissue inflammation in obese mice. We have previously examined epididymal and inguinal white adipose tissues and found that rosiglitazone increased expression of genes important for insulin responsiveness (such as adiponectin and PPARG), but decreased genes associated with inflammation (such as Mac2). In this study, we assessed the same gene expression profiles in mesenteric and retroperitoneal white adipose tissues, two adipose tissue depots that are understudied, but that could be important sites of CLA and/or rosiglitazone metabolism. Rosiglitazone effectively increased insulin sensitivity in mice with CLA-mediated insulin resistance, as made apparent by improved glucose and insulin tolerance tests. Further, rosiglitazone improved CLA-mediated decreases in the insulin sensitizing hormone adiponectin, measured in plasma and in both mesenteric and retroperitoneal white adipose tissues. Rosiglitazone had no effect on adipose tissue inflammation, however. This study demonstrates possible methods to improve CLA-induced weight loss by increasing insulin sensitivity with rosiglitazone treatment, and provides a possible intervention for those struggling with weight-related disease.

Heart disease and other cardiac degenerative diseases account for 1 in 4 deaths in the United States. Current in vitro tissue models for cardiac disease modeling and potential drug testing lack dimensionality, scale, biomimetic behavior, and longevity. Manipulation of biophysical cues via biomaterial scaffolds in 3D bioprinting methods can alleviate these limitations as have been shown in 2D models. By mechanically inducing alignment in 3D tissue models, cells will respond to extracellular cues and form more organized structures similar to in vivo. This project focuses on implementing cardiac muscle cells into a mechanically aligned structure using a decellularized extracellular matrix (dECM) “bioink”. A BioBots extrusion based bioprinting system is utilized to manufacture cardiac cells laden in porcine left ventricle cardiac muscle dECM. We hypothesize that a polycaprolactone (PCL) post system design will induce cell alignment in a band-like tissue structure suspended in a Pluronic F-127 polymer bed along the axis of tension during tissue manufacturing. Induced bioink tension will enhance cardiac structure and function compared to current bioprinted models. This bioink composition and biomaterial process will provide cardiac cells with a better niche for development into a mature state that accurately mimics in vivo conditions. Bioprinted tissues will exhibit increased mechanical properties and structural organization with expression of contractile markers via uniaxial cell alignment upon bioink gelation in culture. This process is high throughput and provides a streamlined standard method for drug screening that more accurately tests possible side effects inside native heart tissue.

Newborns and children are at a much higher risk to adverse drug reactions, which is a significant public health problem. This is partially due to the lack of knowledge of the ontogeny of drug-metabolizing enzymes (DMEs). There are two types of DMEs, known as Phase-I and Phase -II DMEs. Phase I DMEs catalyze oxidation, reduction and hydrolysis reactions. Cytochrome P450s (CYPs) are a superfamily of Phase I oxidative enzymes responsible for the metabolism of a wide spectrum of drugs. Phase-II DMEs are responsible for various conjugation reactions including UDP glucuronidation, sulfonation and glutathione conjugation. Gut microbiome is known to regulate xenobiotic metabolism in adult mouse liver, but little is known of its potential involvement in the ontogeny of DMEs. The goal of this study was to determine the developmental regulation of Phase I and Phase II DMEs using germ free (GF) mice as a model. We bred both control and GF mice under the same housing conditions, and collected livers from male mice at the following ages: Days 1, 5, 10, 15, 25, 60, and 120. We isolated total RNAs and determined the RNA concentration using a Nanodrop spectrophotometer. We also determined the RNA integrity using gel electrophoresis by visualizing the 28S and 18S ribosomal RNA subunits. Using RT-qPCR we quantified the mRNAs of major DMEs and evaluated differences between control and GF mice using T-Test. As compared to age-matched control mice, the mRNAs of the xenobiotic-metabolizing Cyp3a11 was down-regulated in livers of GF mice at multiple ages including Days 10, 60, 120. Conversely, the expression of the lipid-metabolizing enzyme Cyp4a14 was up-regulated at the following ages: Days 5, 15, 60, and 120 in GF mice. In conclusion, our data suggest that the ontogeny of some DMEs is profoundly modified by lack of gut microbiota.

Preclinical screening and toxicity studies are crucial steps in the drug development processes to ensure safety of new compounds when exposed to patients during clinical tests. Cellular responses in blood vessels play an important role in drug screening in terms of permeability and control of blood flow. The structure of the smooth muscle cell layer is crucial to the function of vessels in terms of contractility, mechanical properties and extracellular matrix production. Through recapitulating native tissue properties, tissue-engineered vessel models provide insights to study cellular responses when exposed to different environments, such as drugs. Although much research has been done in the development of tissue-engineered blood vessels, limitations in current in vitro models are yet to be addressed. Existing models such as synthetic and autologous vessel grafts are limited by thrombosis, non-native cellular resonses and poor mechanical properties. Bioreactors or microfluidics device are limited in terms of the complexity of the model and the scale to mimic larger vessels. The project addresses the need for an in vitro tissue-engineered arterial vessel model that replicates in vivo functionalities of the vessel by developing a fabrication method to form smooth muscle cell tubes that is reproducible and functional. The project is divided into three phases: (1) Formation of three-dimensional smooth muscle cell tubes using a cell sheet rolling method, (2) Optimization of the rolling method and (3) Validation of model by contractility analysis. Ultimately, the success of this project allows formation of vessel graft with functionalities in terms of mechanical properties, compliance and contractility. Vascular grafts can be created by human or patient derived sources and serve as drug screening or disease modeling purposes.

Bull kelp, Nereocystis luetkeana, is a dominant kelp forest species in the Salish Sea and plays an important role in the marine coastal ecosystem. The biogenic structure formed by N. luetkeana provides habitat for marine mammals, crustaceans, echinoderms, mollusks, fish, and other algae and increases the productivity of the ecosystem. Throughout its lifecycle N. luetkeana faces a variety of biotic stressors that impact its distribution and abundance. These stressor include competition, availability of sori, the reproductive organ of kelp, and herbivory. The relative impacts of availability of sori and competition on the abundance of N. luetkeana were explored through a subtidal experiment that examined how clearing and seeding impacted N. luetkeana settlement and growth. 40 subtidal plots were placed off of Point Caution, San Juan Island, at approximately 20 feet during a medium low tide. A treatment was then applied to each plot. 10 were seeded with ripe sori, 10 were cleared of vegetation, 10 were both cleared and seeded, and 10 were left undisturbed as a control. The site was monitored via SCUBA over the next 6 months and new recruits of N. luetkeana were recorded. Data suggest that competition between macroalga is the limiting factor in kelp settlement. Once the macroalga survives settlement it still faces other stressors, such as herbivory. Feeding trials with two species of kelp crabs, Pugettia gracilis and Pugettia producta, tested feeding electivity on N. luetkeana using a choice no choice method. Results suggest a preference in both species for juvenile stipe over juvenile blade, and sori over non-reproductive mature blade. P. producta also elected to eat mature blade over mature stipe. Identification of challenges faced by N. luetkeana has the potential to allow for more informed preservation and restoration of kelp beds in the Salish Sea and in other areas.

The use of graphene in nanoscale systems serves many applications not only in solar cells but also in biomaterials because of the combined optical, electrical, and structural properties. Conventional methods including chemical vapor deposition and electrospraying to produce a layer of graphene on nanostructures is costly. Reduction of graphene oxide using chemical reagents presents an easier and cheaper alternative while maintaining the unique properties of graphene. But these methods are typically solution-based and further steps must be taken to coat reduced graphene oxide onto nanostructured surfaces. Dopamine chemistry was applied in a simple simultaneous approach of self-polymerization to reduce graphene oxide while creating an adhesive to incorporate a heterogeneous coating of polydopamine and reduced graphene oxide on a nanostructure. Use of various concentrations of graphene oxide demonstrated control over the sample's surface conductivity profile. Surface analysis characterizations confirmed the presence of the coating through X-ray photoelectron spectroscopy (XPS) while the electrical properties were determined using conductive atomic force microscopy (cAFM). The overall topographical morphology will be confirmed with atomic force microscopy (AFM). A potential application of the proposed device serves to provide functionally and structurally mature human pluripotent stem-cell derived cardiomyocytes (hPSC-CMs) for use in research and clinical drug trials.

Swarm robotics consists of multiple robotic systems that interact with each other within a set environment. Inspiration for swarm robotics comes from behaviors observed in biological systems, namely insect colonies, that migrate collectively. Robots in a swarm are decentralized and behave independently, but their movements are based on that of their surrounding neighbors, thus collective movement is reliant on sensing and modification of each robot. Different algorithms are available for different types of swarms, but the overarching idea of decentralization and simplistic independent behavior persists. The collaborative effort between these robots is critical when performing a task in an efficient and timely manner. However, methods of attaining advanced swarm robotic behavior is limited to expensive laboratory manufacturing. To address this limitation, this work focuses on developing a process for creating low-cost, three-dimensionally printed robots with swarm intelligence. The design of the robotic swarm consists of wheeled robots equipped with sensor electronics, such as proximity and accelerometer sensors, and computer software applications for robot control. Currently, the main application is for tabletop uses such as having the robots work together to form shapes and move small objects. Future applications include human-robot interaction, such as utilizing the robots to provide assistance for the physically disabled. Thus, the main contribution of this work is a manufacturing process for low-cost, three-dimensionally printed swarm robots.

The purpose of this study is to effectively measure and estimate the health impact of common sources of artificial lighting that humans are exposed to at night. To compare the impact of many different types and intensities of artificial light, we have developed an approach for analyzing the profiles of these light sources that evaluates them in terms of the full moon and the way in which the melanopsin photoreceptors in the human eye respond to a full moon. Melanopsin photoreceptors play a key role in regulating circadian rhythms and biological timing in all systems of the body. At an evolutionary scale, natural moonlight is what humans are adapted to, and by comparing full moon exposure (FME) to artificial light source exposure in the context of how much is absorbed by melanopsin photoreceptors, we can understand how unnatural different devices and light sources are at night and compare their relative impact on circadian rhythms and sleep health. The results of this study show that many common electronic devices easily exceed 5X a full moon exposure and can reach as high as 100X. Ambient lighting in the home, from light sources ranging from incandescent to LED deliver well over 100 full moons of exposure at recommended ambient lighting conditions. The implication of these results is that most devices and light sources disrupt normal sleep rhythm in some way and could lead to a variety of health concerns if not properly managed. Individuals can use this data to adjust their light exposure at night, to make adjustments to urban lighting in cities, and to inform architects and designers to light residential spaces in a way that minimizes health risk.

The environment plays a large role in shaping someone’s future, especially their academic achievement. Children who have access to necessary resources, such as books, quality schools and teachers, have been shown to perform better in many subjects. In this study, we examined the associations between Socioeconomic Status (SES) and academic success in college-aged students. Also, we examined the choices that a student makes, such as amount of time spent in the workplace, and the format of classes taken (i.e., online, hybrid, face-to-face), and how they predict students’ academic success. SES was assessed by parent education and household income. We predicted that students who have a high SES will perform better academically than those who have a lower SES. Students who work full time will be more likely to take classes in an online format, to fit their work schedules. Conversely, students who work part time or not at all will take classes in the standard, face-to-face format. We predicted that students who work part time or not at all will perform better academically as they can dedicate more time and effort to their schooling than students who work full time. To answer our research questions, we examined college students who took a 30 minute online survey assessing SES, types of classes taken, how many hours worked in part-time and/or full-time jobs, and academic achievement (i.e., GPA). Implications of these results may inform colleges of the various needs of support based on types of classes taken to better students’ academic achievement. Future studies should examine additional measures of SES (e.g., Income-to-needs ratio) and how that impacts the associations between SES and academic achievement.

The phytoplankton assemblage around the Olympic region is well described, but due to the various hydrologic and oceanographic features that affect water conditions, little is known about the phytoplankton assemblage in the Chehalis River Basin. This research seeks to provide an outline of common species of different locations, the environments in which they were found, and the obstacles that block their movement. To do this, sampling sites around the basin that would cover various different geographic features of the Chehalis River Basin were selected, along with the phytoplankton sample, salinity and temperature were taken, and wind direction and strength were taken to determine if an upwelling or downwelling phase could be predicted. When back at the lab, toxin and chlorophyll samples were filtered for future analysis and saved. Microscopy was performed to identify species, if a harmful algal bloom species was identified, a whole water cell count was performed. Species that were found ranged from freshwater to marine; however, frequently species that are marine were found in low salinity environments. These results can be used to identify locations of interest in further studies and could be used to identify areas that may be useful for shellfish harvesting.

Safety precautions are only effective when implemented properly. This is a major obstacle when using wearable devices to promote workplace health and safety. User compliance is a serious concern: Is the user using the device and is it worn as intended? Monitoring user compliance using electronic sensing systems faces limitations. The systems must be cost effective, small, and fit the form of the wearable device all while maintaining enough power to be beneficial. This research monitors compliance in the proper wear of safety eyeglasses within these limitations and constraints. Specifically, information on safety eyeglass orientation and location on the head is gathered continuously using a hall effect sensor mounted on the glasses themselves and a magnet mounted on the user’s ear. Tests on six different users (including both male and female adults) show that four different positions (on the bridge of the nose, on the tip of the nose, on the forehead, on the top of the head) of the glasses can be detected for each user and four different motions, all beginning in the proper ‘on’ position on the bridge of the nose, can also be detected. The overall error rate for data sets collected among six different users is less than 10% and error rates within any one user did not exceed 25%. Collecting both transient motion and steady-state position data minimizes error rates for understanding user compliance. These preliminary tests demonstrate the viability of using these safety glass monitoring systems for not only understanding where the glasses are at any point in time but also how they got there. This information is useful to not only capture non-compliance but also to understand behavior well enough to support effective measures to increase compliance (of wearing safety glasses when they are needed).

The purpose of this research is to better understand the connections between dice and elections in voting theory. We explored the phenomenon of nontransitivity in dice and elections. In a set of 3 dice, labeled A, B, C, it is straightforward to designate sides such that, on average, A beats B, B beats C, and C beats A. Similarly, in an election of more than two candidates, where voters create a preference list for the set of candidates, it is simple to make nontransitive relationships in voter preference. Motivated by these situations, we aimed to find a correspondence between these two mathematical objects. Additionally, we defined the concept of an overall winner for a set of dice and an election, and explored the effects of nontransitivity in determining it. We used tournaments (from graph theory) as a tool to visualize the relationship structure among dice and elections. As a result of this work, we have shown that, from any dice set, an election can be constructed such that the dice possess the same winning-losing relationships. The converse is also true: given an election, a set of dice can be constructed with identical winning structure to the election. We defined the notion of a contest, which serves as a classification for both objects. Finally, we developed a triangular inequality for contests, and proved that dice and elections both satisfy this inequality.

For many, mathematics is just the language of numbers. But, what people forget is that the universe is made of numbers, thus mathematics is its language. That is why we used a mathematical approach to study the long-term behavior of a moving ball influenced by the Earth’s gravitational field. For our purpose, we experimentally defined gravitational billiards to be vertical billiards in which the earth gravitational field affects the billiards ball’s motion. We also assumed that the billiards boundary could be any mathematical function of our choice, and the experimental system was conservative. Once in motion, the billiards ball followed a two-dimensional projectile trajectory until collision with the boundary occurred. After that, the ball engaged in a new projectile trajectory. As a matter of fact, each trajectory between two points of ball-boundary collision could be considered as an isolated two-dimensional gravitational motion with its own set of conditions. We took advantage of that aspect to build different simulations in parabolic, circular, paraboloidal and spherical gravitational billiards. The long-term behavior of the ball under gravity in our different gravitational billiards presented some aspects that so far corroborated the physics behind our study.

Electric vehicles have gained attention in recent years as an environmentally friendly alternative for conventional, gasoline-fueled vehicles. While internal combustion engines power gasoline-fueled vehicles, electric vehicles use electric motors or batteries for propulsion. It is true that electric vehicles produce little to no tailpipe emissions and, overall, produce fewer pollutants than comparable gasoline-powered vehicles. However, when comparing the total environmental impact of electric vehicles to their gasoline counterparts, it is important to consider the associated impacts from the electricity grids from which they glean their power. In the United States, modes of electricity production vary by geographic location and include coal, natural gas, petroleum, nuclear, hydroelectric, and renewable sources. The purpose of this research has been to understand and quantify these environmental impacts and communicate them in an accessible manner to K-16 learners. To date, only the greenhouse gas emissions of electric vehicles have been quantified in such a way, providing equivalent miles to the gallon compared to gasoline vehicles by state. Our research efforts have taken this comparison one step further by capturing equivalent emissions of lead (Pb), land usage, and water usage of electric vehicles for every state in the U.S. While useful in and of itself, this information has been embedded in clickable maps, various multimedia, and exhibits for K-16 audiences using principles of exhibit design that allow a participant of any age to understand and absorb key principles surrounding electric vehicle usage in the United States. Effective exhibit interactives emphasize the engagement of all five senses through physical activity and stimulate visitors both intellectually and emotionally. Our exhibits and presentations have been carefully engineered to convey factual and intuitive information to K-16 students in an inviting, exploratory, and accessible manner.

In “Writing Against Culture,” Lila Abu-Lughod writes, “The process of creating a self through opposition to the other always entails the violence of repressing or ignoring other forms of difference.” This complicated discourse Abu-Lughod describes emerges from 19th century colonialist practices, which oppressed colonized peoples, and therefore rendered their "identities" troubled. As literary modernism gained traction in the 20th century, Caribbean writers such as Frantz Fanon and Jean Rhys responded to the suddenly complicated identity paradigm in which they become marked as the “Other.” How do Fanon and Rhys untangle modernist notion of the self while being deeply entwined with constantly alienating effects of colonialist practices? In this paper, I explore the extent to which “the violence of repressing or ignoring other forms of difference” causes colonized people to react loudly against these forces with their own newly constructed identities. Rhys and Fanon reacted loudly in their work, but other colonized people would react loudly through force and violent resistance. Black Power movements in the Caribbean and America, for example, feature the colonized seizing upon new identities in order to break free of colonialism and the identities it imposed. Fanon’s reaction to break free of those shackles are manifested in Black Skins, White Masks, which becomes essential for these Black Power movements. Rhys creates Wide Sargasso Sea to problematize the racism of 19th Century colonialism itself and highlight the vicious process of identity formation via a famous work of Victorian literature. Through my research, I have ultimately come to the conclusion that colonialist oppression produces identities contrary to it, whether that may be in the form of writing or other violent movements; it is that very narrative process by which colonial power breeds its own undoing.

Water-absorbent polymer networks known as hydrogels are attractive materials from which functional tissue substitutes could be developed using patient-derived stem cells. While hydrogels demonstrate biocompatibility conducive to harboring cells, they lack mechanical and biochemical aspects of the native extracellular matrix (ECM), the intricate microenvironment about which cells function. Conventional photopolymerization-based techniques provide an avenue for incorporating these stimuli within hydrogels, but at the expense of introducing propagating free radicals that are prone to non-specific reactions with biological systems. In light of these limitations, we have developed a strategy for hydrogel formation and modification absent of propagating free radicals, proceeding through oxime ligation moderated by a photocaged alkoxyamine. Upon mild UV light exposure, the photocage is cleaved, liberating the alkoxyamine and permitting localized condensation with an aldehyde to form an oxime-based linkage. After synthesizing multi-arm crosslinkers, functionalized with either benzaldehydes or photocaged alkoxyamines, I demonstrated successful formation of oxime-based hydrogels within minutes of light exposure in the presence of live cells. Through a series of rheological studies, I found polymerization rates and final mechanical properties of these gels could be systematically tuned by varying crosslinker concentrations, light intensity, aniline catalyst concentration, and pH. Harnessing the light-driven aspect of this chemistry, I controlled hydrogel geometry and final mechanical properties by dictating the location and extent of UV exposure, respectively. I then translated photomediated oxime ligation toward the biochemical modification of hydrogels, where full-length proteins containing photocaged alkoxyamines were immobilized in user-defined regions exposed to UV light. The programmability afforded by photomediated oxime ligation can recapitulate mechanical and biochemical stimuli found throughout the ECM, which are dynamic and heterogeneous in their presentation. Consequently, photopolymerized oxime-based hydrogels will enable an enhanced understanding of cell-matrix interactions by serving as improved 3D cell culture platforms, thereby leading to advancements in tissue engineering and regenerative medicine.

Many scholars have constantly claimed that a shift from defined benefit plans to defined contribution plans has been the wrong course of action in policy and it has brought direr effect to the economy. Economists have argued that defined contribution plans are generating inefficiency pension income for employees in the private sectors, creating further cost burden for taxpayers and discouraging employees to stay at a job. While most observers are accepting the current situation by sticking to the traditional defined benefit plans, there are significant indicators in which the shift to defined contribution plans is inevitable. Economic shocks such as financial crisis, new health policy like Affordable Care Act and Congress abolishment of the Aid to Families with Dependent Children federal assistance program have changed the tides. They have brought a great deal of attention on how defined contribution pension plans can shape agents’ behavior in the labor market. Using datasets from the Survey of Income and Program Participation (SIPP) Synthetic Beta file and the National Quarterly Workforce Indicators, this paper examines the proposition that defined contribution plans motivate newly hired workers to stay at a job for a much longer period and gain higher weeks at pay without federal assistance programs taken place. This occurs particularly for male employees in public sectors. Regression analysis (OLS and logistic) demonstrates that workers enrolled in defined contribution pension plans have increasing personal level annual earnings taxed under FICA, higher probability in having employer- based health insurance and a larger family size in their individual households. Furthermore, this paper attempts to explain whether defined contribution plans have transitory or permeant effect on workers’ wellbeing during economic shocks using unit root test to determine whether there exists a stochastic trend.

Keywords: defined contribution pension plans, labor market, individual households, workers

The purpose of this research was to create a pedagogical tool to be used by college professors in effectively teaching jazz improvisation in a group setting. Throughout the history of jazz and jazz improvisation, many works have been created to aid in the individual’s education and understanding of the art form. However, there have been no recent pedagogical works to aid the teacher in conducting group improvisation classes, as has become the common method of instruction. Thus, this research is unique and necessary to help further jazz education in our students. The following presentation details the processes and findings of a combination of various research dating back from the 30s through today, spanning the genres of jazz music, jazz improvisation, and teaching. The research was informed via survey of various professors and jazz musicians across the United States, three interviews, and many different books read, websites scoured, and documentaries watched. These factors combined accumulates into the following three semesters of curriculum for jazz improvisation.

We have recently identified a new cytosolic sensor for bacterial cyclic dinucleotides, the aldo-keto reductase RECON. RECON plays a critical role in surveying the host cytosol for intracellular bacterial pathogens, orchestrating the innate immune response to those pathogens and aiding in bacterial clearance. In the host, RECON is most highly expressed in the small intestinal epithelium, enterocytes and M cells. Its high expression at these important mucosal immune sites raises the question as to whether RECON is part of the intestinal immune system. We have recently made a RECON knockout (KO) mouse and found significant alterations in intestinal inflammation and commensal abundance, particularly an increase in segmented filamentous bacteria (SFB). Using quantitative real-time PCR copy number analyses of SFB 16S gRNA, we detected high SFB burden in the RECON KO mice while SFB was undetectable in wild-type mice. SFB have been shown to impact the development of the immune system, particularly T cell populations, in rodents by colonizing and attaching to the follicle-associated epithelium of the small intestines. We predict that the high abundance of SFB in RECON KO mice may either be the result of immunosuppression due to the presence of too many T regulatory cells or will associate with the increased presence of pro-inflammatory T helper type 17 cells. Current work is aimed at establishing whether there are changes in these T helper cell types in the intestine, as well as looking at the broader dysbiosis by 16S deep sequencing. This project will establish which immune axes are dysregulated in the absence of RECON and will direct future mechanistic investigations into how loss of RECON enzymatic activity is driving immune dysregulation.

Studies using primary airway epithelial cells from asthmatic and healthy donors have reported differences in gene expression of a variety of genes between cells from asthmatic and healthy donors. However, few studies have investigated the stability of gene expression by primary cells with increasing cell passage number, or how viral infection might affect the stability of gene expression with increasing cell passage number. This research investigated: 1) whether expression by primary bronchial epithelial cells (BEC) of genes IFIH1, which codes for a viral sensor protein with an important role in the innate immune response, and TGFβ2, a pro-remodeling cytokine, from asthmatic and healthy children, is stable with increasing cell passage number, and 2) if BEC infection with respiratory syncytial virus (RSV) alters the stability of IFIH1 and TGFβ2 expression with increasing cell passage number. To answer these questions, we differentiated passage 1, 2, 3, 4, and 5 BECs from asthmatic and healthy children at an air-liquid interface for 3 weeks. RNA was then harvested from BECs and RT-PCR was performed for TGFβ2 and IFIH1. To assess the expression stability across increasing cell passage number for each gene, we compared expression at passages 2-5 to expression at passage 1. Preliminary data collected shows that expression of TGFβ2 and IFIH1 from asthmatic and healthy children was stable with no significant differences between passages 1, 2 and 3. However, expression at cell passages 4 and 5 was significantly greater and more variable than by passage 1 BECs. We anticipate gene expression to be even more variable for RSV-infected passage 4 and 5 BECs. These observations illustrate the importance of using BECs from passage ≤ 3 when comparing gene expression between asthmatic and healthy primary BECs, and of characterizing the expression pattern across increasing cell passage number for each gene studied.

This abstract is no longer available. Please contact urp@uw.edu if you have any questions.

This abstract is no longer available. Please contact urp@uw.edu if you have any questions.

Algal subsidies are extremely important to the success of the deep benthos where there is little to no primary productivity. Little research has been done on the nutritional value of detritus, such as pieces of kelp, that sink into deep habitats. Sea urchin feces, as a form of detritus, may provide an energetic link from shallow-water algae to these deep benthic communities. Urchins are known to have an inefficient digestive system which creates the potential for feces to be of high food value. In this study, relative caloric contents of algae and of feces of the red sea urchin (Mesocentrotus franciscanus) were analyzed by chemical assay. Algal biomass consumed and feces egested by urchins were quantified, as were the caloric contents of fresh and aged urchin feces fed a diet of bull kelp (Nereocystis luetkeana). In all cases, the caloric content of algal material increased after being consumed by urchins, and the longer the urchin feces aged, the higher the caloric value became. It is likely that microbiota inside urchin guts are driving these counterintuitive results. The creation of calorie-rich feces could add to the importance of urchins as a link to benthic communities that rely heavily on detritus for their success.

Knowing the age structure of a population improves demographic models, but birds lack many structures, such as teeth and otoliths, used to age other animals. Marking and following large numbers of individuals is required to know the age structure of a penguin population beyond the distinction between juvenile and adult plumage. In a large population of Magellanic penguins (Spheniscus magellanicus) at Punta Tombo, Argentina, we coded eye and foot color. The penguins ranged from less than one year to more than 28 years of age. We examined iris pattern and color, defining “distinct” eyes as reddish-colored irises with concentric red and pink rings and “indistinct” eyes as dark-brown irises. More than 75% of 2-3 year-old Magellanic penguins had distinct eyes, compared to 50-75% of 4-6 year-olds, 25-50% of 7-20 year olds, 10-25% of 21-24 year olds, and <10% of 25+ year olds (n=3262). Foot color progressed from mostly white to mottled to mostly black. We also examined foot color in a small known-age zoo population of Humboldt penguins (Spheniscus humboldti). In Humboldt penguins, feet became mostly black within a year of hatching, but continued to darken slowly with age (n=44, maximum age=25 years). In Magellanic penguins, feet took several years to become mostly black (n=190). Nestlings had mostly white feet with small specks of black (n=16). About 88% of adults 3-11 years old had mottled or mostly black feet, while the remaining 12% had white or fully black feet (n=90). 24 of 25 adults 23 years or older had black or almost black feet. Individual variation in both eyes and feet prevents aging an individual with a high degree of certainty, but a population may be split into broad adult age classes based on eye and foot color.

Eelgrass (Zostera marina) are important ecosystem engineers that provide food and habitat to diverse organisms. Some eelgrass beds are declining in locations around the Salish Sea, leading to a subsequent decline in biodiversity and productivity. One proposed restoration strategy is to transplant shoots from healthy to declining sites. Transplantation efforts, however, should consider the effects of desiccation on eelgrass during extreme low tides. Desiccation can decrease transplant success by decreasing photosynthetic rates and causing tissue damage in transplanted shoots. To understand how desiccation affects transplanted eelgrass performance, we conducted a mesocosm experiment that manipulated air exposure durations to simulate eelgrass transplantation between tidal elevations. Plants collected from three tidal heights in Ship Harbor, WA were randomly placed in tide tanks that mimicked the emersion periods of three different tidal elevations. We measured changes in eelgrass morphology, growth, and tissue damage throughout the experiment. We predicted that shoots in treatments with similar air exposure durations as their original locations would exhibit the highest growth rates and the least amount of damage. We found that eelgrass originating from a high intertidal zone that were exposed to a low intertidal treatment exhibited the least amount of bleaching damage. Neither origin nor treatment, however, affected eelgrass growth rates. Our findings suggest that transplanting shoots from the high to low intertidal zone is a useful strategy for eelgrass restoration.

Cocha Cashu Biological Station in the Amazonian rainforest of Southeastern Peru hosts a myriad of plants and animals, with one study reporting 230 avian species found in 80-100 ha study plots. Such incredible species diversity may be attributed to the adaptation of specialized hunting behavior and morphological traits allowing for habitat partitioning of forest strata. In our study we hypothesized that we would find differences in wing and tarsus morphology in birds living at different forest strata. Over a five-day period, twenty birds were captured by mist nets and used for data collection. From these individuals, wing length to weight and tarsus length to weight ratios were explored to seek a correlation between them and the heights at which different avian species were observed. We predicted birds with lower wing length to weight ratios, and thus more compact morphology, specialized for flight at lower strata. Furthermore, ground-dwelling birds tend to have a longer tarsi for efficient bipedal locomotion on the forest floor, leading us to predict that birds with lower tarsus length to weight ratios would be observed at higher strata. We found that individuals with shorter tarsi and longer wings relative to body mass tended to be found in higher strata. Our results supported our hypothesis, suggesting adaptations in wing and tarsus morphology facilitate partitioning of forest strata. Morphological analysis of avian populations foraging at different heights is critical for developing an understanding of the evolutionary processes underlying these specializations, and for effective conservation management. Although our predictions regarding correlations between morphology and vertical distribution were confirmed in this study, a larger dataset is necessary to better support our findings. Continued research will allow for accurate predictions to be made concerning how avian populations will respond to fluctuating environmental conditions such as altered migration patterns, climate change, and deforestation.

 As the world looks for sources of clean energy, the recent advances in lead halide solar cells have shown great promise, increasing from 3% efficiency to 20% in the last few years. Many lead halide or perovskite devices provide the opportunity for low carbon solar cell manufacturing, yet they are still scaled to laboratory settings. By using additive solution based treatments, large-area high-efficiency solar films can be scalably processed through the rapid deposition of perovskite solvents onto roll to roll printers similar to the printing presses used in the newspaper industry. In order to allow for the scaling of the perovskite solar cells, areas of improvement are needed on the small scale with perovskite films on glass substrates, including the need for rapid thermal processing to reduce processing time from 30+ minutes to a matter of seconds. In our work, various methods of rapid thermal treatment on perovskite films were performed by using a xenon flash lamp under different experimental intensities and time series. The flash lamp uses high pulses of energy that interact with the film to rapidly heat it while avoiding degradation due to quick thermal dissipation. These samples will be characterized using X-ray Diffraction, UV-Vis Spectrometry, and Scanning Electron Microscope in order to examine the degradation and grain growth effects. Then, the results will be compared to samples thermally treated from 10 minutes to an hour. Future work of this heat treatment process will be used to optimize the rapid thermal processing needed to roll coat scalable perovskite solar cells films onto a flexible plastic substrate, polyethylene terephthalate (PET). The xenon flash lamp will be attached to the roll to roll printer which will print large area flexible perovskite solar cells to reduce wasted processing energy, and meet increasing energy production needs.

Ocular dominance columns (ODCs) are neurons that are organized in V1 of the visual cortex to respond to input from either eye preferentially. ODCs create stripes on the surface of V1, which have been shown to be less pronounced when the animal loses visual input before the critical period of ODC formation. It was previously believed that these ODCs did not exist in rodents. ODCs correlate with connections from the corpus callosum, which can be seen as a patchy pattern of callosal connections. When rats were found to have similar patchy callosal connections, it was hypothesized that rats would have ODCs as well. As a result of this, our lab was able to find that Long Evans rats have segregated ocular dominance domains. In our current experiment, we looked at plasticity of ODC formation in rats who are either monocularly deprived or enucleated during the critical period of ODC formation. First, we performed either a monocular deprivation (by suturing the eyelid of the rat shut) or a monocular enucleation (by removing the eye) before the onset of the critical period. We performed anatomical analyses by injection of a label for callosal connections and ODCs in the cortex. V1 of the visual cortex was then removed and examined. Furthermore, we performed physiological tests using electrophysiology. In these experiments, we looked at visually evoked responses of both eyes from the monocularly deprived rats (after the suture was removed). The results of our experiments have shown that monocularly deprived and enucleated rats show less patchiness in ODCs contralateral to the closed/removed eye and less patchiness in callosal connections. Also, we found that there was greater ipsilateral response of the non-damaged eye to visual stimulation in rats. These results show that there is plasticity in rats deprived/enucleated before the critical period. 

Composite materials utilizing nanoparticles can exhibit improved properties and qualities. Silica (SiO₂) nanoparticles exhibit unique optical, electrical, and mechanical properties and are an ideal candidate for the dispersed phase in many applications, such as precursors for optical films with controlled optical properties and rheology. Atomic forces dominate when particles shrink to sizes below the visible wavelength spectrum, generating unique phenomena. One problematic phenomena, however, is the agglomeration of primary particles into a polydisperse collection of dimer, trimer, or larger secondary particles when calcined or mixed into the continuous phase of the composite. Monodisperse colloids and nanopowders are critical for consistent and optimized performance of composites and nano features. Silica particle synthesis has been well researched, but the practicality of producing pure, monodisperse, and non-agglomerated particles at scalable operations is still in question. This research investigates the factors leading to the agglomeration of spherical silica nanoparticles when synthesized with variations of the Stöber method, and evaluates changes in synthesis parameters that can reduce agglomeration in order to determine the most viable process for scalable production. Parameters that are manipulated include the ratio of ammonia catalyst with tetraethyl orthosilicate (TEOS) in ethanol or methanol solvents and the addition of anionic electrolytes. SEM imaging is then used to evaluate the distribution of the particles. Surface treatments for anti-agglomeration as incorporated into the synthesis process or as post processing are also evaluated, with minimal remnant impurities in the product as a priority. The end goal of this research is to successfully synthesize monodisperse sub-10 nanometer silica particles for pseudoplastic shear-thinning precursors used in fast throughput nanoimprinting of an antireflective layer for solar cells.

Researchers are working to determine in-depth information about the substructure of the proton. This includes the proton's fundamental charge and current distributions, described by functions called electric and magnetic form factors. These form factors have traditionally been determined by computing elastic electron-nucleon scattering cross sections, to first-order expansion in the electromagnetic fine structure constant, α_e—encompassing a process called one-photon exchange. Experimental discrepancies in the proton's electric-to-magnetic form factor ratio have prompted a need to compute cross sections to second order expansion in α_e, involving two-photon exchange (TPE) interactions. Two methods for calculating TPE cross section contributions exist: one based on hadronic degrees of freedom (suitable at low Q², where Q is the four-momentum transfer between the electron and nucleon) and the other on partonic (quark-level) degrees of freedom (applicable at high Q²). Both methods have been claimed to principally account for the form factor discrepancy. However, ambiguities exist in the separation of the parts of the cross sections independent of the underlying hadronic structure (“soft” parts) and the parts dependent on such structure (“hard” parts). We aim to resolve such ambiguities by first rederiving current quark-level calculations to better understand exactly how the hard and soft parts of the cross section are separated and the underlying physical motivations. Furthermore, we plan to compare these calculations to known behavior of the hard part of the cross section in the limit that the scattering angle goes to zero. Ultimately, our objective is to pave the way toward a unified description of TPE effects at all Q² values. Achieving this goal will further pin down the nature of the proton's interior, and the results in turn can be used to better understand the neutron and other hadrons.

Single-junction solar cells that employ metal-halide perovskites have generated intense interest due to their rapid increase in demonstrated power conversion efficiency. In contrast with previously explored solar cell active materials, perovskites are solution-processable, tunable band-gap materials with small energetic losses. Because of this they are ideal candidates for use in tandem solar cells, which integrate a large-bandgap and a small-bandgap solar cell into one structure, significantly increasing maximum efficiency. Current tandem solar cells can have marked efficiency loss due to excess window layers and poor layer design leading to absorptive losses. Additionally, the comparatively poor understanding of perovskite processing methodology can result in suboptimal perovskite active layers. Our goal was to explore the feasibility of using a metal grid-type electrode collection layer in place of a standard transparent window layer, in order to minimize absorptive losses for successful integration into a tandem structure. Principally important to characterizing this structure was exploration of device fabrication and perovskite processing methods that resulted in effective carrier extraction. The mean diffusion length of charge carriers in a material is one of the primary factors that affect carrier extraction. Current literature gives a diffusion length ranging from 0.3 – 10 um for methylammonium lead iodide (MAPI) perovskite layers. We fabricated test cells with electrode grid pitches ranging from 0.4 – 10 um using photolithography techniques. We then explored the effect of variable deposition method, heat treatment and solution composition as well as observed layer morphology on diffusion length and charge extraction using photoluminescence spectroscopy.

In the last 10 years, perovskite solar cell efficiencies have increased from four to over twenty percent. Perovskite materials possess great application in thin-film photovoltaics and roll to roll processing. Unlike in traditional silicon solar cells with layer thicknesses on the order of 100 microns, the perovskite layer in a thin-film photovoltaic can be fewer than 100 nanometers. This study looks at the suitability of zinc oxide nanoparticles for use as an electron transport layer in a lead halide perovskite thin-film. Of particular interest is the ability to adjoin the zinc oxide and perovskite layers without any degradation of the perovskite. The effects of solvents, additives (i.e. surfactants), and particle size are analyzed using a variety of methods such as x-ray diffraction, transmission electron microscopy, and photoluminescence spectroscopy to determine optimal interfacial properties and exciton separation in the electron transportation layer. The success of the ZnO layer is further analyzed by comparing the quantum efficiencies and current-voltage characteristic curves of the assembled solar device to an identical solar cell that uses PCBM as the electron transport layer. PCBM is one of the most effective electron transport layers, but due to high cost, the need for alternatives such as ZnO was made necessary. The overall goal of this project is to attain efficient solar cells, using cost-effective materials and processing methods. By doing so, it will open up the field of solar energy for a wider market and broader applications.

There is a problem with teamwork nowadays because members are not in the same place at the same time. Communication media allows for teamwork to proceed regardless of where members are located. There are many types of media available including phone, email, and communication applications such as Skype, Messenger, WeChat and so on. However, the communication media itself is also an important factor influencing the effectiveness of teamwork. This research focuses on studying teamwork from the perspective of individual communication media preferences rather than just the objective productivity potential. I present my insights to date, drawn from a literature review about communication media and teamwork and lead to a theoretical framework about the way communication media preferences influence outcomes. The framework displays two approaches affecting outcomes: 1) the quantitative approach that affects the quantity of information being carried out during a given period, and 2) the qualitative approach of quality that impacts the precision, specificity and directness of information. Finally, my future research steps are presented including a survey for testing the theorized framework using students completing a team project, and potentially other workforce teams. The work will advance knowledge about effective teamwork that can help organizations be more productive.

Spinal cord injury (SCI) disrupts the communication between the body and the brain. As a result, people with SCI typically have significant sensorimotor deficits leading to a lower quality of life. Electrical epidural stimulation (EES)—that is, the stimulation of the spinal cord from the surface of the cord—has shown promise for enhancing recovery of the hindlimbs when applied to the thoracic spinal cord. The goal of this study is to determine whether this same therapy applied to the cervical spinal cord in rats with cervical injuries can improve forelimb function. Prior to injury, the rats perform multiple tasks: Irvine, Beatties and Bresnahan (IBB) task, Limb-use Asymmetry Test (LUAT), Automatic-pellet-reaching task, and a Lever task. Next, rats will receive a unilateral C4 hemicontusion and below the injury the rats will receive an epidural implant for stimulating the spinal cord. All of the rats will perform the former tasks—IBB and LUAT—once a week to track their recovery. Half of the rats will be stimulated via the epidural implant while performing the automatic-pellet-reaching task and Lever task in the hopes of inducing Hebbian plasticity to enhance functional recovery. We are currently testing different epidural implants to identify a method that provides robust, long-term EES. Post-injury performance will be compared to the rat’s pre-injury performance. Subsequently, the rats are perfused for tissue analysis. We are optimizing the tissue analysis protocols for identifying GAP-43 immunoreactivity to determine if there was an increase in plasticity and axonal growth. Cresyl violet and myelin staining will also be used to measure the magnitude of the injury by staining the spared neurons and myelin.

Recent studies have shown that electrical stimulation of the spinal cord can manipulate spinal cord plasticity and may be effective in recovering motor function after spinal cord injury. The emerging field of optogenetics allows researchers to change a cell’s membrane potential using light. Cells are made to express light-dependent ion channels (channelrhodopsins) which cause a cell to depolarize or hyperpolarize after being triggered by specific light wavelengths. Our lab has shown that optogenetics can be used to elicit forelimb movements in rats by stimulating the cervical spinal cord. Long-term methods for providing light stimulation in vivo are needed to explore the treatment potential of optogenetics. Initial experiments by our group using a LED implant stimulator demonstrated that long-term optogenetic stimulation of the spinal cord results in increased GAP-43 staining. GAP-43 staining highlights areas of new neuronal growth, suggesting an increase in neuronal plasticity in optogenetically stimulated rats. Animals in this study, however, also exhibited unusual tissue morphology around the site of implant. Current research is working to understand the possible sources of this tissue disruption, including heat production from the LED and inflammation induced by LED stimulator implantation near a spinal cord injury. To investigate the possibility of heat production, I developed a new implant prototype that incorporates a thermistor to monitor temperature changes during long-term light stimulation. I tested this implant design in anesthetized and freely-moving rats to investigate how different light stimulation parameters affected implant temperature. I then performed histological tissue analysis at the site of the implants to assess the effects these temperature changes had on tissue condition. The results from this work will inform the next generation of light stimulation implants, and help to improve function following spinal cord injury via optogenetic activation of neural tissue.

Microglia are the resident immune cells of the central nervous system, and are responsible for acute inflammatory responses when injury or infection is detected. However, chronic neuroinflammation has been implicated as a key precursor to neurotoxicity, and thus microglia play crucial roles in neurodegenerative disorders. cMaf is an anti-inflammatory transcription factor that mediates neuroprotective functions of microglia such as tissue repair and phagocytosis of cell debris. In 2014, the Garden Lab published results detailing a hypothesized pathway in which cMaf is downregulated by the cell-cycle regulator p53. However, these results were observed in p53 knockout murine microglia that likely have developed compensatory molecular responses to the lack of this critical transcription factor. To determine if acute p53 deletion by Cre-recombinase in floxed-p53 murine microglia influences cMaf expression we utilized AAV-Cre to infect floxed-p53 microglia, which sheds new light upon the current hypothesis regarding the relationship between p53 and cMaf. In this project, we also explored the effect of overexpression of cMaf by infecting wild-type microglia with exogenous cMaf to overexpress cMaf and examine the resulting impact on microglial activation and phagocytosis of apoptotic bodies using flow cytometry. We use quantitative real-time PCR and Western Blot to analyze the immunological impacts of cMaf overexpression in microglia. The implications of this research extend to a wide range of neurodegenerative disorders, like ALS and Alzheimer’s disease, where dysfunctional inflammatory responses may contribute to disease pathology.

Fizikl is a company that uses UAVs to count inventory in warehouse. The goal of the company is to replace the manual inventory counting method that most of the companies uses. Our team worked on the barcode detection and scanning process, as well as the centering of the UAV. The first step to achieve autonomous warehouse is to pinpoint the UAV's waypoints and designate its flight plan. Then, the UAV will take pictures upon arrival at each destination point after centering itself according to the Aruco codes. The distance between the camera and the shelf is carefully set to a fixed value to capture all the items on the shelf. The pictures will then be sent to a ground station where barcode extraction and counting will happen. Th barcode scanner algorithm will also output the location on the pictures where it finds barcodes. We have optimized the barcode detection process by testing the barcode detection algorithm with different qualities of barcodes. We have experimentaly determined how many pictures the UAV should take at a certain destination. We have successfully built a inventory counting system to achieve autonomous warehouse.

Although questionnaires are helpful for identifying employee retention targets in research contexts, such surveys do not benefit employers in small, real-world organizations due to the inevitability of gathering biased data (e.g., due to social desirability or lack of anonymity). The purpose of the current study was to test a tool employers could use to more accurately identify turnover risk and targets for individualized retention strategies. This tool focuses on employee engagement, which research has shown to be related to employee turnover (i.e. high engagement is related to lower employee turnover intentions). This tool enabled us to determine employee level of engagement and predict employee group identification (i.e. long-term retention vs turnover). We hypothesized that higher levels of engagement will predict employee long-term group identity, whereas, low levels of engagement will predict turnover group identity. We conducted a qualitative study using a between-subjects design to compare semistructured phone interviews with 25 community mental health clinicians (13 long-term, 12 turnover), in which we asked clinicians what “ideal changes” they would like to implement in their agency. Using the Q12 Engagement Measurement Model, derived from Maslow’s Hierarchy of Needs, we determined clinician engagement levels, which we then used to predict their group identification. We predict our analyses will reveal that clinicians who suggest more personal-level changes are more likely to be in the turnover group, while clinicians who suggest more altruistic-level changes are more likely to be in the long-term retention group. The literature indicates that employees with higher engagement levels are less likely to turnover; therefore, if we achieve our predicted results, future implications of this study could be that employers could use this tool in their annual review process to more accurately assess employee turnover risk and improve employee retention strategies.

The recent changes in our climate drive the need for a more comprehensive understanding of the workings of the environment so that we can more accurately simulate the changes taking place around the world. This project aims to do this by studying measurements of the optical depth of tropical clouds at different heights. The optical depth of a cloud is how opaque it is to visible radiation and determines how effective the cloud is at absorbing or scattering the solar radiation. By sifting through radar and lidar data collected by NASA’s CALIPSO and CloudSat satellites that orbit the earth simultaneously in a group called the A train, I am able to determine cloud optical depths as a function of altitude in different regions. I expect the optical depth of tropical clouds to decrease as their height increases due to the fact that lower, warmer clouds are able to hold more water and should therefore be thicker. My research adds additional information for climate models so that they may more accurately define the radiative budget.

Necroptosis is a lytic and immunogenic form of programmed cell death (PCD), characterized by pro-inflammatory cytokine production and the release of intracellular molecules, including cell-associated antigens. In the context of tumor immunology, tumor cell death is a necessary step in causing the release of tumor antigens, allowing for antigen-specific tumor recognition by the immune system. However, how distinct forms of PCD within tumor cells could differentially instruct immune recognition of tumor-associated antigens remains poorly understood. Our research question addresses how the immune system responds to cancer cell death, and will help determine whether necroptosis can promote tumor immunity. We propose that induction of necroptosis within tumor cells could promote anti-tumor immune responses by releasing tumor antigens accompanied by pro-inflammatory signals, resulting in potent immune recognition of cancerous cells. To study the immune responses to cell death in tumors, we have modeled the effects of various cancer cell death programs using flank tumors implanted in B6/J mice. Using flank tumors engineered to express versions of various pro-death signaling proteins that can be activated, we show that induction of necroptosis within the tumor microenvironment leads to robust tumor control. Measuring serum cytokine levels, in addition to analyzing the identity and activation status of immune cells isolated from the tumor tissue following treatment, will yield critical insights towards the immune cell subsets and signaling axes responsible for the observed response to necroptosis. These experiments provide us with a comprehensive understanding of whether cell death in a solid tumor has a therapeutic benefit as well as the underlying mechanism of the immune response to dying cells within a solid tumor. Considering the pro-inflammatory nature of necroptosis, it represents a promising therapeutic target in the context of cancer immunology.

There is an urgent need to clarify the causes of Alzheimer’s Disease (AD) so targeted treatments can be developed. Mutations in Presenilin 2 (PSEN2) cause an inherited form of AD, but the mechanism for this relationship is not fully understood. PSEN2 protein (PS2) has been found to regulate pro-inflammatory microglial response and the expression of microRNA miR146, an innate immune regulator. These findings led us to pursue the effects of PSEN2 mutations on microglia function, peripheral immunity, and AD. Our aim is to study mechanisms of microglia-induced neuron injury in AD. We hypothesize that PS2 mutation-expressing microglia contribute to neuroinflammation in AD by cytotoxicity and synaptic pruning mechanisms. To study the impact of stimulated microglia on neurons, we employ co-cultures, where microglial (BV2) and neuronal (SY5Y) cell lines are cultured together. We used a lactose dehydrogenase (LDH) cytotoxicity assay to measure levels of microglia-induced neuronal death. After initial assay optimizations, we measured LDH of a BV2/SY5Y coculture to quantify baseline LDH and optimize the ratio of neuron to microglia plating. Fluorescent microscopy was used to observe microglia and neuron interactions morphologically and flow cytometry quantified the levels of neuron phagocytosis of microglia. Using these methods, we were able to demonstrate interactions between the cells and these same methods can be used to later study synaptic pruning. From here, we will determine whether there is a difference in synaptic pruning levels and cytotoxicity between microglia from a control mouse and a mouse expressing mutated PSEN2 transgene when co-cultured with neurons. If our hypothesis holds true, we expect to see increases in both cytotoxicity and synaptic pruning induced by mutated microglia. Determining and understanding PSEN2’s role in causing AD could lead to the development of targeted treatment for patients with these mutations.

Mutations in the gene Presenilin 2 (PSEN2) cause familial Alzheimer’s disease (fAD). FAD shares clinical and pathological features of sporadic, late onset AD thus fAD cell models can be useful to study mechanisms relevant to all forms of AD which is critical to developing effective AD therapeutics. Presenilin 2 protein (PS2) forms the catalytic subunit of the γ-secretase complex, which cleaves amyloid precursor protein and releases Aβ1-42, considered a pathogenic contributor to Alzheimer’s disease (AD). Our laboratory is interested in a fAD associated PSEN2 mutation, a frameshift two base-pair deletion (PSEN2 K115Fx) . The PSEN2 K115Fx is predicted to either lead to a truncated protein suggesting that the mutation may create a shortened peptide that interferes with normal cellular function (dominant negative or toxic gain of function) or result in degradation of the RNA transcript and subsequent loss of normal amount of PS2 protein (loss of function). To better understand how PSEN2 mutations cause disease, we have two objectives. The first aim of this project is to determine if the PSEN2 K115Fx does indeed result in a truncated protein or influence levels of wildtype PS2. I will be collecting human cultured fibroblasts isolated from AD patients with the PSEN2 mutations or controls and prepare cell lysate for analysis by Western blot. My colleague will also be analyzing mRNA levels from those same samples to determine the stability of the PSEN2 mutant and wildtype transcripts in all cases. The second aim is to determine the impact of the mutation on PS2 enzymatic activity. I will culture the cells described above, then infect with a luciferase based enzyme reporter assay to compare the impact of PSEN2 mutations on γ-secretase mediated cleavage of APP. My work will help identify the candidate mechanisms by which the PSEN2 K115Fx mutation causes AD.

A large body of research has examined the association between disadvantage and crime in neighborhoods, usually finding a strong positive association between neighborhood disadvantage and crime. Neighborhood disadvantage is associated to crime via a variety of pathways, including, but not limited to, reduced educational opportunities and reduced collective efficacy (i.e., the ability of residents to control or influence the behavior of other individuals and groups in the neighborhood). However, research that links neighborhood disadvantage to crime has not examined the effects of clustering, better understood as grouping, of neighborhoods on the relationship between neighborhood disadvantage and crime. In metropolitan areas, predominantly minority-occupied, disadvantaged neighborhoods are often grouped together into specific areas. In other words, poor neighborhoods are adjacent to other poor neighborhoods compounding the disadvantage that inhabitants of these neighborhoods face. This is important to understand because it means that segregation of neighborhoods may be helping to drive high crime rates within neighborhoods. I extend this body of research by considering the role of clustering in the relationship between neighborhood disadvantage and crime. I use data from the National Neighborhood Crime Study, which includes tract, city, and metropolitan level variables to analyze crime and spatial inequality. The poverty and spatial proximity data is provided by the Neighborhood Change Database, which includes tract level data for impoverished neighborhoods as well as longitude and latitude of said neighborhoods. I use these two data sets to analyze the effects of neighborhood clustering through various data analyses. Preliminary data analyses show a statistically positive relationship between spatial proximity and number of murders. From this, it is expected that spatial proximity will also have a statistically positive relationship with overall crime.

Understanding the role of fluids in active fault zones and the coevolving relationship between fault activity and fluid movements is significant in tectonics research. Calcite (calcium carbonate) veins are a record of past fluids in previously fractured rocks, giving insight into the past environments and conditions for faulting. Studying the characteristics of faulting in the past is key to understanding faulting in the present. I studied carbonate fluid precipitates in carbonate fault rocks from three major fault zones located in the Apennine fold and thrust belt of Italy to better understand this complex coexistence. The faults in this area are active and produce earthquakes. By taking thin sections of rocks from specific domains within the fault zone and using a petrographic microscope, I identified different phases of calcite relating to different stages of fault deformation. Carbon and oxygen isotopes from the CaCO₃ act as tracers for fluid source and evolution. After I identified the characteristics of the minerals that make up the fluid precipitates, I analyzed the minerals for relative abundances of C¹³ and O¹⁸, to better characterize the source of the fluids. These measurements have already been made on rocks from the same area, so I aimed to reproduce the isotopic tracers previously found. This research and characterization of the specific faults and fluids is key in preparing for future clumped isotope measurements.This further work will involve the measurement of relative abundances of a specific isotopologue of CO₂ in our samples with clumped O¹⁸ and C¹³. Temperature and clumping of these isotopes is directly related by the laws of thermodynamics and thus allow us further insight into the origin of fluid originated carbonate veins.

Today, volatile gas anesthetics are commonly used in medicine for various procedures. While they are effective and safe for most adults, multiple or long exposures of anesthesia to young children and infants is thought to carry the risks of neurodevelopmental defects due to the well-established neurotoxic effects of anesthetics on the developing nervous system, referred to as anesthesia induced neurotoxicity (AIN). If the mechanisms of anesthesia and AIN can be studied and better understood, strategies to prevent defects associated with AIN can potentially be developed. At the Seattle Children’s Research Institute, I am assisting as an undergraduate researcher in a project to better understand AIN. My project specifically involves using C. elegans, a laboratory invertebrate species, to study the effects of anesthesia on neurotoxicity in specific developmental stages, including programmed cell death (apoptosis). The short life span and rapid reproductive cycle of these nematodes make them great models for this study because isoflurane exposure has been observed to induce AIN in these organisms. I am working to research the specific developmental stages of C. elegans that isoflurane affects the most. In lab, I am culturing worms to known stages of development, using green flourescent protein (GFP) reporter strains as markers to study apoptosis (specifically in the apoptoic proteins ced-3, ced-1, and ced-10), and exposing worms to isoflurane during these stages. Using PCR, western-blotting, and imaging techniques, I am analyzing the proteins, neurons, and developmental stage(s) impacted by AIN. This should provide new insight into the proteins and specific neurons that anesthesia induced neurotoxicity targets. By carefully analyzing the mechanisms of AIN, I hope to gain knowledge about how it can damage normal neuronal function in C. Elegans that can eventually be applied to humans.

The large-scale configuration of the cosmos has long been a mystery to astronomers. My research project aims to shed light on this mystery. The overarching goal for my research project is to further understand the distribution of matter on 10⁵ –10⁷ light-year distances by comparing numerical simulations to actual observations of the universe. This comparison tests the current theoretical parameters of the physics governing the largest scales of the cosmos. I used simulated data from models made by Professor Matthew McQuinn and observations of quasar spectra from the Very Large Telescope (VLT). From the VLT data, I analyzed quasar spectra for absorption lines at a hydrogen electronic transition called the Lyman-alpha line. The IGM absorbs amply at this transition, creating absorption lines throughout the quasars’ spectra. I processed this data by programming Python scripts to compare flux probability distribution functions (PDFs) of the Lyman-alpha absorption in the observed quasar spectra to the simulated quasar spectra. Through this comparison, PDFs of observations fell within one standard deviation of the simulated PDFs. Although at higher redshifts (further back in cosmological time), there was considerably more variance. In order to further constrain the observational flux PDFs, I aim to eliminate systematic and statistical uncertainties that may make the observations spuriously differ from models. The salient errors include fitting precise continua (spectra without absorption) and removing metal (predominantly carbon-4) contamination from the Lyman-alpha forest. I used Principal Component Analysis to predict the continuum spectrum but found that a fit by eye was more effective. Through analysis of absorption probabilities outside the Lyman-alpha forest, I statistically removed carbon-4 from the data inside the Lyman-alpha forest. Ensuring the most precise flux PDF measurements are used is critical to the comparison of observations to simulations and to the constraints of parameters governing the universe.

Quorum Sensing (QS) is a chemical signal based communication system by which bacteria regulate gene expression according to changes in population density. This communication mechanism is used by the environmental bacterium and opportunistic human pathogen P. aeruginosa, which is a major cause of Cystic Fibrosis (CF) lung infections. P. aeruginosa employs two interconnected QS systems: las and rhl. These systems are regulated by the transcription factors LasR and RhlR, each of which binds a unique chemical signal that further activates transcriptional regulation. LasR and RhlR together control the expression of virulence factors critical for many infection processes. In laboratory strains, the LasR and RhlR QS systems are arranged hierarchically, such that LasR transcriptionally activates RhlR. Although this QS hierarchy is common to laboratory strains of P. aeruginosa, some CF clinical isolates are capable of RhlR activation in the absence of functional LasR. However, the origin of this LasR-independent regulation remains unclear. In this study, we investigate whether the LasR–RhlR hierarchy is conserved in environmental P. aeruginosa. We collected several environmental isolates and genetically engineered them through allelic exchange mutagenesis to disrupt LasR function. We then transformed wild type and LasR-null isolates with reporter constructs that produce GFP (Green Fluorescent Protein) in response to either LasR or RhlR. In these two conditions, we measured protein levels of LasR/RhlR, signal concentrations and the production of several QS-regulated products. In most cases, we observed that RhlR activity was substantially reduced in the absence of functional LasR. The observed decrease in RhlR function is so far consistent with the idea that the QS hierarchy is a conserved feature of P. aeruginosa. However, mechanisms of quorum regulation in environmental strains may differ from laboratory strains and a proper understanding of them can potentially contribute to the development of non-antibiotic therapies.

In this paper, we studied the terrestrial mammalian populations through surveying both the northeastern and southwestern sides of Cocha Cashu within Manu National Park, Peru. The northeastern side of Cocha Cashu, which is an oxbow lake formed by the river meandering, is dominated by primary Amazonia rainforest while the southwestern side is mainly an early successional forest. Our study goal was to document the mammalian species diversity in Cocha Cashu by focusing on large-sized mammals. Previous studies have focused on rodents, marsupials, and bats, but the ecology of the larger mammals remains unknown. We conducted our surveying using five camera traps placed on each side of the lake at corresponding locations of projected terrestrial mammalian hotspots. We monitored these sites by checking them once daily and therefore had four nights and three full days of surveying. Through the identification of species from the photos on our camera traps we were able to find the species richness, total number of sightings at each site, and total number of sightings per species as well as comparing the number of sightings and species between night and day. The primary forest side had a total of five species (Leopardus pardalis, Dasyprocta, Cuniculus paca, Mazama americana, and Tapirus) and ten sightings, while the early successional side had a total number of four species (Dasyprocta, Tayassu pecari, Panthera onca, and Tapirus) and six sightings. Ultimately, our results show that primary forests in a tropical climate support a higher diversity of terrestrial mammals, as well as a higher number of individual mammals when compared to early successional forests. These data may assist future researchers in placing camera traps in areas of high mammalian diversity and density. Large mammals are keystone species in ecosystems and their existence affects prey populations and the composition of the surrounding flora. This research also confirmed the existence of many important keystone species such as the Tayassu pecari, Leopardus pardalis, and Panthera onca and provided records of occurrence in different types of habitat, which may help future conservation of different species and which type of habitat they prefer.

It is widely recognized that there is limited understanding of many animal- plant interactions and the complex networks they form with other species. I conducted an observational study, in the Coshu Cashu field station in the Manu National Park in Peru, to determine the plant-pollinator relationship that Zygia coccinea, a flowering tree in the Fabaceae family, has with the insects that visit it. Very few studies have been conducted on Z. coccinea and the few that have been conducted focused on classifying the characteristics of the plant and did not look at the plant’s ecological role in the environment nor at other species associated to it. It is important to understand the dynamic interaction between vegetation and their insect population to gain a more thorough understanding of the complexity of the ecosystem dynamic and how it may be impacted by alterations in the composition of species present. I used two different observational techniques, scan and focal, in order determine the diversity of the insect network associated with Z. coccinea. I observed 101 different individuals, classified 19 distinct morphospecies, and identified individuals in seven different Orders. In particular, we observed an insect of the Order Homoptera, a small cicada-like pink pigmented insect that was found being herded by ants (similar to other ant-aphid interactions) which seems to be a new species for science, and further research needs to be conducted. This study is important because it contributes to the knowledge of specific insect-plant interactions. In addition, it was the first time an insect visitation network was identified for Z.Coccinea and upon the establishment of this network, a potential new species to science may have been found.

Joubert syndrome (JS) is a genetic neurodevelopmental disorder with medical features including a distinctive hindbrain malformation and developmental delay. All 35 JS-associated genes to date encode gene products localizing to the primary cilium but the mechanism behind JS is still unknown. The primary cilium serves as a cellular antenna for signaling, and when dysfunctional, can lead to the above features and more. One JS-associated gene, INPP5E, is an enzyme that controls phosphatidylinositol (PI) subtype distribution in the ciliary membrane. We hypothesize that abnormal distribution of PI subtypes PI(4,5)P₂ and PI(4)P in primary cilia is central to the JS mechanism, and therefore should be present across genetic causes. To test this hypothesis, I used fluorescently-tagged PI biosensors, domains from naturally occurring proteins that bind to different PI subtypes, and a domain from serotonin receptor (5-HT₆) that marks cilia. The PI biosensors were already tagged with GFP (green fluorescent protein) so I replaced GFP for RFP (red fluorescent protein) on the PI(4,5)P₂ biosensor, and inserted BFP (blue fluorescent protein) on the 5-HT₆ domain, allowing me to distinguish all three molecules in the same primary cilium. To do this, I removed the GFP sequence from our PI(4,5)P₂ plasmid using restriction enzymes that cut DNA then inserted RFP (amplified from a template plasmid carrying RFP) using DNA ligase. I confirmed the RFP insert by restriction enzyme digests specific for RFP and by direct DNA sequencing. PI(4,5)P₂-RFP plasmids were transformed into cells with PI(4)P-GFP and our BFP ciliary marker, then live-imaged. These tools will make it possible to determine if abnormal PI subtype distribution in primary cilia is a unifying cellular defect in JS patient cell lines. If so, we can then explore the effects of altered PI distribution and determine whether modulating PI distribution has the potential for mitigating the effects of Joubert syndrome.

Joubert syndrome (JS) is an autosomal recessive neurodevelopmental disorder, characterized by the "molar tooth sign" on axial brain MRI. JS is caused by mutations in 35 known genes, all of which encode proteins that localize to the primary cilium, a microtubule-based organelle that projects from the surface of most cells. Our current understanding of the underlying molecular mechanism causing JS involves lack of ciliary localization of ARL13B and INPP5E, two JS-associated proteins. ARL13B is required for the ciliary localization of INPP5E. Normal INPP5E localization maintains a phosphatidylinositol subtype distribution in the ciliary membrane. My research investigates ciliary phenotypes in cell lines harboring causal mutations in C2CD3, which encodes a protein that localizes to the primary cilium’s basal body, using existing images of patient cell lines. Loss of C2CD3 function in mouse models has presented lower ciliation rates and shorter cilia lengths. Previous research in our lab on two other JS-associated basal body proteins, OFD1 and KIAA0586, identified normal ciliary ARL13B-INPP5E levels. To determine ARL13B and INPP5E localization, cells from two control and two different C2CD3 patient cell lines were grown and serum-starved, inducing ciliation. Cells were stained with antibodies to acetylated tubulin (marking cilia), and INPP5E or ARL13B (marking protein of interest). Using Fiji, an image analysis software, I “painted” each cilium by outlining the signal in the acetylated tubulin reference channel to define a mask. Using that mask, I quantified ciliary ARL13B and INPP5E. I measured ciliation rates using the number of masks divided by the number of nuclei, and cilium lengths using the “skeleton length” function. Based on data from mouse models, we predict that C2CD3 patient lines will have fewer and shorter cilia, but normal ARL13B-INPP5E localization. These expected data would exclude the hypothesis that INPP5E mislocalization is an obligate part of the biological mechanism underlying JS.

Historical forest landscape patterns are necessary to generate landscape level restoration treatments. Though landscape and disturbance patterns due to fires are well understood and recorded on public forest lands east of the Cascade Mountain Range, factors like fire suppression, long fire return intervals of west-side forests, lack of documentation, climatological differences, and extensive timber harvest complicate implementing similar strategies on landscapes west of the Cascades. By examining the distribution of smaller forest patch sizes, in addition to patches that were subjected to low-severity burning as a part of the 2015 Goodell burn for mortality and survival, we can derive and quantify factors necessary for early seral habitat creation (the critical establishment phase in ecological succession; historic proportions of early seral habitat have been approximated, and current levels are comparably lower). By interpreting stereo imagery and burn severity maps of the Goodell burn, and by employing GIS and remote sensing techniques, historically compatible models and landscape-level restoration strategies for both terrestrial and aquatic habitat can be utilized in guiding and monitoring restoration efforts.

At low obliquity, planets like Earth will tend to form permanent ice sheets at the poles, if anywhere. However, at high obliquity, the poles receive more sunlight on average than the tropics, and so ice sheets might be expected to form at the equator. We have used a simple energy balance model for investigating the orbital, atmospheric, and obliquity parameters that allow for the formation of permanent ice at the equator. We find there is a narrow range of semi-major axis and obliquity values that allow for such “ice-belts”. First, we experimented with the range of stability of ice-belt formation by increasing the semi-major axis to the edge of the habitable zone, increasing CO2 levels to counteract the decrease in solar flux. This led to a very small range of conditions that allow for stable ice-belts. To further investigate the cause of this, we decreased the luminosity of the host star while increasing CO2 levels (to simulate the control temperatures). This stabilizes the otherwise unstable system, although the range of ice-belt formation is still narrow. Further, we find that this equatorial ice formation often leads to instability due to the ice-albedo feedback. This work suggests that it should not be common for Earth-like worlds at high obliquity to maintain large ice sheets.

An object's color is composed of three dimensions: hue, brightness, and saturation. According to Opponent Process Theory, hue is determined by two opposed chromatic color mechanisms (red versus green, and blue versus yellow). The red-green and blue-yellow balances of an object are determined by the activity of the three retinal cone-photoreceptors: S-, M-, and L-cones which have peak activations at short, medium, and long wavelengths of light. S- and L-cones are responsible for the perception of red and oppose M-cones which signal green, and M- and L-cones the perception of yellow and oppose S-cones which signal blue. Previous research has shown how achieving a red-green balance can be influenced by various brightness effects. This current study demonstrates how these same stimuli are influenced by manipulating saturation. We displayed a variety of colored stimuli that varied in their saturation and red-green balance. Saturation was manipulated by the experimenter by adding blue phosphor to a colored stimulus composed primarily of red and green phosphor on a CRT monitor in order to create 6 different experimental conditions. Participants were asked to set a colored stimulus on the screen to a red-green balance by varying the amount of red and green phosphor with a keyboard, with the blue phosphor levels being held constant. Results show that as more S-cone activating blue phosphor was added to the stimulus participants adjusted the stimulus more toward the direction of M-cone activation (green). This is the predicted direction of Opponent Process Theory since L- and S-cone activity add together to signal redness. We conclude that as you reduce the saturation of a red-green balanced stimulus by adding blue, the stimulus will appear redder. Psychophysical researh like this can help guide ideas to design safety signs, materials for people working in low-light environments, or other real-world physiological investigations.

Both content knowledge and problem-solving strategies are important components for academic success in biology. All problem-solving strategies begin with the ability to understand the problem being presented. In the context of biology, this means identifying the core concept being asked in complex questions. Identifying keywords, words that are important or significant, can help students identify these core concepts. The purpose of this study was to explore how well students can identify keywords and if this ability is correlated to exam performance. Students in an Introductory Biology course took weekly practice exams (PE), after each PE they either graded their own or a peer’s PE. In addition, students were asked to “identify the keywords in the question that should have caused you to provide the complete and correct answer given in the key”. This experimental design also allowed us to explore how grading an anonymous PE affects quality of students’ keyword selections. Students’ keyword selections were compared to a keyword rubric created by the research team. Data was coded by two researchers to 90% inter-rater reliability. On average, students only correctly identified 39% of keywords each week. Multiple regression models were used to explore correlations between correct identification of keywords and performance on both PEs and course exams. Interestingly, students who self-graded were more consistently engaged with the keyword activity as compared to peer-graders. In both cases, percent keywords correct could predict overall exam performance. These results indicate that if instructors want to help students improve their problem-solving skills of complex biological problems, helping students recognize keywords may be one solution. Furthermore, identifying which students have trouble simplifying complex exam problems and helping these students improve their ability to identify keywords may be beneficial in addressing learning disparities within large introductory classes.

Student-graded practice exams (PEs) have been used to facilitate learning in large classrooms. In a large introductory biology class, we investigated the impact of self vs peer-grading of PEs. We hypothesized that students who graded their own PEs would grade more accurately than peer graders because they are more motivated and reflective in their grading. Over time this more accurate grading would lead to increased performance on course exams. One question from each week’s PE was graded by a team of experts. We calculated PE grading accuracy by comparing the expert grade to the grade assigned by the student. We analyzed the correlation of PE grading accuracy with exam performance. For each metric we investigated the impact of treatment, incoming GPA, and student demographics (e.g., gender, socioeconomic status, first generation, race/ethnicity) using general linear models. There was no difference in average expert PE grade between the two treatments. Incoming GPA was the only significant predictor of expert PE grade with GPA positively correlated with expert PE grade. There was a significant interaction between incoming GPA and treatment on grading accuracy. Students with high GPAs who graded peers consistently underestimated their peers’ PE performance. Students with lower GPAs who graded peers either graded similarly to experts or slightly overestimated their peers’ PE performance. Students who graded their own PEs more accurately predicted their PE performance regardless of incoming GPA. There was an interaction between GPA and treatment on course exam performance, as high GPA self-graders earned more course exam points than high GPA peer-graders. Average GPA students earned the same amount of course exam points regardless of treatment. Given these findings and the logistical complications of peer-grading in large classes, instructors can use the more easily administered self-grading method of providing feedback on low-stakes practice exams.

We investigated how grading treatment, self-evaluation versus peer-evaluation, on weekly practice exams (PE) in an Introductory Biology course affects the advice students give to improve academic performance. We hypothesize that students who suggest more resources and study strategies perform better on course exams because they are aware of how improvements need to be made and what resources to use. Students in the class (approximately 550) take a PE on Thursday and then grade the PE responses on Friday. The grading groups were split up into two treatments: half of the class self-evaluated whereas the other half evaluated their peers’ responses. In addition, they were prompted to answer two questions: 1) Pick a single thing that you/this student should work on. 2) What resource should they consult before the next exam? We used this information to explore how study strategies and resources that students suggest relate to their test scores. To analyze the responses, we created specific codes corresponding to student answers. Results of the codes indicate that the students’ responses fall into four categories for question 1 and two sets of categories for question 2 (with three and two codes in each set). When asked to provide ways to improve PE performance, the four specific codes were being descriptive, increasing knowledge of content, interpreting the question, and time management. When providing resources, the two sets of categories were active versus passive resources and expert, peer, and self resources. Over the course of ten weeks, students who suggested more strategies and resources tended to perform better on exams. As well, both self-evaluators and women in the course suggested more strategies and resources than peer-evaluators and men respectively. Given this study, instructors can better understand what resources students are utilizing but also which study strategies tend to be more successful for students.

Climate change has lowered the reproductive success of the Magellanic penguin (Spheniscus magellanicus) population at Punta Tombo, Argentina contributing to the population’s 37% decline since 1987. While increased rainfall and storm intensity directly affect reproductive success through chick mortality, the indirect effects of weather can also impact fitness. We predicted that temperature would alter penguin behavior in two ways: 1) fewer penguins would leave the colony on hot days since traveling in heat requires more energy, and 2) penguins leave earlier on hot days to escape the highest temperatures of the day. Automatic scales that record weight, time, and direction were placed where penguins frequently exit and enter the colony. The scales also recorded the Radio Frequency Identification (RFID) number of the penguins for 5,000 crossings, allowing us to calculate their trip duration. Days were considered hot if the maximum temperature was greater than two standard deviations above mean maximum temperature (>28℃, n=11 days) and cold days were less than two standard deviations below (<20℃, n=11 days). Temperature did not affect when penguins exited or entered the colony, however, more penguins exited and entered the colony on hot days than on cold. A greater number of penguins took short trips (<= 12 hours) on hot days than on cold days, suggesting they only go to the beach to cool down, rather than to forage. Increasing temperatures could lead to parents leaving their chicks alone at the nest for longer durations of time without foraging which could increase chick mortality.

Mussels, Family Mytilidae, are vital to intertidal ecosystems and to a burgeoning aquaculture industry. They act as ecosystem engineers within their environment by controlling resource availability to other organisms and by shaping the structure of their habitat. Unfortunately, with the rise of anthropogenic climate change, mussel populations are seeing growing threats to their ability to survive and reproduce. This includes lower recruitment, increased susceptibility to disease, and weakening of the byssal thread that adheres mussels to their substrate. Understanding the life history of these organisms, in addition to what food sources and conditions are most suitable for their growth, is essential for preserving this economically and ecologically vital species group. Mytilus trossulus, a common species of saltwater mussel ubiquitous in the aquaculture industry was used in this study. The mussels were grown at two different depths on aquaculture lines for comparison of the environmental effects at those depths. The first layer at 1 meters depth consisted of a mixed surface layer rich in phytoplankton growth and represented a warmer, more variable ocean environment. The second layer was found below the surface mixed layer at 7 meters depth and represented a colder, more constant environmental regime. By analyzing the food sources of these mussels through fatty acid extraction, we will draw conclusions not only about what nutrients are most beneficial to mussel growth, but also what effects the environmental differences between the two depth strata has on the mussels. The purpose of this study is to both provide data for the care of mussels in aquaculture farms and to make inferences about what a changing climate will mean for these organisms.

The Cretaceous-Paleogene (K-Pg) mass extinction is the most recent of the ‘big five’ mass extinctions and led to the extinction of all dinosaurs except birds. Theropod dinosaurs, which were mostly carnivorous, were important members of latest Cretaceous terrestrial ecosystems. A popular hypothesis for the K-Pg mass extinction is that a meteor impact caused rapid extinction of many taxa 66 million years ago (Ma). The fossil record of dinosaur skeletons is not sufficient to assess the timing and pattern of the K-Pg mass extinction and its potential cause(s). Here, I documented theropod diversity using a sample of 783 fossil teeth from eight localities that span most of the depositional duration of the Hell Creek Formation (HCF; ca. 1.9 million years). To test the hypothesis that the bolide-impact was the sole cause of the mass extinction, I wanted to determine if significant changes in theropod diversity occurred before the impact at the K-Pg boundary. New and updated taxonomic identifications were based on the current literature. Raw, range-thru, and rarefied taxonomic richnesses as well as relative abundances and heterogeneity indices (evenness, Simpson’s) were calculated for each of the fossil localities. In total, eight theropod taxa were identified from the HCF. Richness shows a slight decrease from eight taxa in the lowermost HCF locality to five to seven taxa higher in section. Rarefied richness was lowest in the uppermost HCF. Although the changes observed in richness are minor, relative abundance and heterogeneity values differed significantly from the middle to upper HCF localities implying that major changes in theropod faunas occurred locally within the last few hundred thousand years of the Cretaceous prior to the bolide impact. Similar patterns have been observed in the amphibian and mammalian faunas suggesting other environmental factors (e.g., volcanism, climate change) contributed to the causes of the mass extinction.

My project focuses on macroscopic analysis of indigenous pottery from the Iron Age in Mallorca, Spain. My first goal is to develop an efficient method of analysis that can be used with large samples of pottery collected in the Landscape, Encounters and Identity Archaeology Project. I am recording a number of traits for individual ceramic pieces, such as color, texture, and temper. For each of these traits, I am evaluating the replicability, speed, and amount and types of tools needed to record them. My second goal is to use this information to understand the variability within indigenous pottery. Traditionally, this pottery has been divided into two types based off of fairly rigid criterion, which masks the potential variability within each type. This method of analysis, along with multivariate statistical analysis of the data collected, will help to characterize the variation within each type in order to better understand indigenous pottery production techniques.

Fundamental understanding of how effector T-cells are transformed into quiescent memory T-cells is vital for developing immunotherapeutic treatments for autoimmune diseases and cancer, and for the development of vaccines against diseases such as AIDS, tuberculosis and malaria. Previous research on conversion of memory precursor effector cells (MPECs) into memory T cells has found evidence of Treg cell involvement in the process. Treg cells are regulatory helper T cells which selectively inhibit effector T cells to prevent and suppress overly strong immune responses and autoimmune responses. Research has also shown that MPECs produce their own IL-2, a cytokine involved in immune tolerance and activation. Based on these data, we hypothesize that direct interaction between MPECs and Treg cells, possibly via MPEC-produced IL-2, is required for conversion of MPECs into memory T-cells. We also addressed colocalization of Treg cells with short-lived effector cells (SLECs). SLECs are IL-2 non-producing effector cell counterparts of MPECs and do not form memory. Potential MPEC or SLEC interaction with Treg cells was visualized through immunofluorescence microscopy of the secondary lymphoid organs (spleen and lymph nodes) of experimental mice injected with lymphocytic choriomeningitis virus (LCMV). To bypass the low precursor physiological frequencies of MPECs we employed the P14 LCMV GP33-specific TCR transgenic mouse system, which is a well-regarded model system for studying memory differentiation. To test the role of IL-2 in cell-cell interactions, we used IL-2 agonist and antagonist antibodies. A detailed understanding of how Treg cells are involved in the process of MPEC to memory T cell conversion is key to developing novel immunotherapeutic treatments.