The transient receptor potential vanilloid-1 (TRPV1) ion channel is a polymodal receptor expressed in sensory neurons that contributes to inflammatory pain sensation. Interestingly, the receptor channel is modulated by specific phosphoinositide lipid molecules in the plasma membrane. During inflammation, phosphoinositide 3-kinase (PI3K) generates the signaling lipid phosphatidylinositol (3,4,5)-triphosphate (PIP3). This increase in PIP3 levels leads to trafficking and fusion of vesicles containing TRPV1 with the plasma membrane. Previous research from the Gordon Lab revealed that increased PI3K activity is potentiated by TRPV1 during inflammation. However, the mechanism behind potentiation is undetermined. We hypothesize that stabilized association of PI3K with the plasma membrane by TRPV1 results in increased PI3K activity. To visualize the spatial localization of PI3K and its interaction with TRPV1, we employed a special optical technique called total internal reflection fluorescence microscopy (TIRFM). In TIRFM, selective excitation of fluorophores adjacent to the plasma membrane allows us to study translocation of proteins from the cytosol to the plasma membrane, or vice versa. We utilize TIRFM in conjunction with an opto-PI3K system to better understand PI3K signaling events during inflammation. We transiently transfected F-11 cells, model cells for dorsal root ganglion neurons that sense pain, with fluorescently labeled opto-PI3K system components and TRPV1 ion channels. Our fluorescence measurements show that, upon stimulation with 650 nm light, PI3K is retained at the plasma membrane through interaction with TRPV1. TRPV1 retention of PI3K is direct evidence for the hypothesized mechanism of potentiation through membrane localization. Studying PI3K activity in the prescence of TRPV1 will elucidate key properties of potentiation, such as affinity of the interaction, effects on PI3K activity, and substrate selectivity. These findings will aid in the development of inflammatory pain treatments that disrupt the interaction between PI3K and TRPV1.

While humans cannot regrow a limb after amputation, animals like the Xenopus tropicalis tadpoles can fully regenerate their limbs. How metabolic pathways are reprogrammed to support the demand for anabolic building blocks needed for regeneration is still not understood. Our group has found that while regeneration increases glucose intake, tadpole tail regeneration does not depend on glycolysis for precursors to support proliferation. This result suggests a redirection of glucose flux to pathways other than glycolysis, specifically the pentose phosphate pathway (PPP). Previously, I inhibited glucose-6-phosphate dehydrogenase (G6PD), a key enzyme in the PPP, with the pharmacological antagonists dehydroepiandrosterone (DHEA) and G6PDi and showed that inhibitor-treated tails are much shorter compared to dimethyl sulfoxide (DMSO) controls. From these results, I predicted that the PPP is required throughout regeneration to support increased cell proliferation rates. To investigate if the PPP is required for increased cell proliferation during regeneration, I performed phosphohistone-H3 (pH3) immunohistochemistry to label mitotic cells. Histone-H3 is phosphorylated at the start of mitosis, making pH3 a marker for actively dividing cells. The results showed that amputated tadpoles with inhibited PPP have reduced cell proliferation rates compared to controls, confirming that the PPP is required to support rapid cell proliferation during regeneration. To determine if the PPP has a shorter critical activation window during regeneration, I treated amputated tadpoles with PPP inhibitors while varying the length and start-time of treatments. PPP-inhibited tadpoles have significantly shorter tails as treatment length increases, regardless of the start time for PPP inhibition. This result suggests that PPP activity must be sustained throughout regeneration to fully regrow the tail. My work has therefore identified the PPP as a previously unknown but critical metabolic pathway promoting tadpole tail regeneration. This insight advances our understanding of how metabolic reprogramming provides the carbon building blocks for regeneration.

Possession Sound, located in Everett, Washington, includes the second largest source of freshwater in Puget Sound from the Snohomish River. This salt-wedge estuary serves as a home to a wide selection of phytoplankton, which provide energy to a variety of organisms farther up the food chain. Water chemistry often determines where phytoplankton accumulate prior to their recycling as nutrients. Ocean Research College Academy students utilize water chemistry data (temperature, salinity, dissolved oxygen, pH, turbidity and chlorophyll concentration) from two sensors deployed in Possession Sound: One in the river and one two miles away at Mukilteo. While plankton samples are collected in the Sound, rarely are plankton collected in the river and compared to chlorophyll concentrations. This study will look at abundance and diversity of phytoplankton collected in the river at various tide stages and compare these to Mukilteo samples. I hypothesize that flood tide samples will be similar, while ebb tide phytoplankton and chlorophyll levels will decrease. The preliminary data revealed that chlorophyll and temperature levels did not vary significantly between the two sites despite the widely differing salinity levels. The next steps of the study are to determine the plankton density of phytoplankton species across the two most recent years of data. Results will enable us to explore further into plankton presence in relation to chemical variance in water systems. 

Ocean acidification is a global crisis that is mainly caused by too much carbon dioxide in the atmosphere being absorbed by bodies of water, altering the water chemistry. Ocean acidification has large visual consequences, such as the bleaching of coral reefs, but less obvious, small scale influences are also found in the Salish Sea. A major indication of global warming’s effects on local water systems is pH, or the measure of how acidic or basic a solution is. Previous global studies have shown that pH has been decreasing (becoming more acidic) over the years, while the overall temperatures have been rising. The goal of this study is to observe how changes in lowernig pH are related to temperature changes in the watercolumn of Possession Sound, a salt wedge estuary, near Everett, Washington. We utilized pH and temperature vertical profiles collected from a YSI EXO Sonde, a deployment device that utilizes sensors and precise calibrations to monitor water quality, over six years to assess the degree of ocean acidification locally. Trends were analyzed according to depth and season. Preliminary studies of this particular site have shown minor changes compared to the extreme trends recorded in other ocean environments. Given the potential for negative impacts on the estuary, it is worth expanding the study by investigating a longer time frame. Local estuary data regarding depth and season will allow people to better understand how these variables change in our environment and gain a greater understanding of climate change’s influences on ocean acidification locally.

There is often a stigma associated with bilingualism due to the mistaken belief that bilingual children develop language skills at a significantly slower rate than monolingual children. To combat this misconception, it is necessary to conduct research showing that bilingualism either helps or does not harm language acquisition when compared to monolingualism. This study attempts to meet that general need by determining how bilingual and monolingual children compare in metaphor comprehension. I decided to focus on metaphors because they can be challenging for children to interpret correctly, and I hypothesized that bilingual children would perform better on metaphor comprehension tasks than monolingual children because of their regular use of second labels. I investigated how 127 monolingual and bilingual children ages 2.5-4.5 years old responded to a set of metaphors by using a game-like format to gather data via Qualtrics. Specifically, I gave children a series of 10 metaphor questions in which they needed to choose which of two pictures best fit a provided metaphorical phrase. Children were also given 10 vocabulary questions derived from the metaphor questions to ensure that children knew the literal meaning of the words. Results showed that bilingual children performed slightly but significantly better than monolingual children on metaphor comprehension questions. Currently, I am also collecting data for a follow-up study to replicate and extend my findings. These results are important because they give us insight into how child language development differs between monolingual and bilingual children and counter negative stereotypes about bilingualism.

Universities hold expectations of students to possess forms of cultural and social capital in order to be successful in their educational careers. This may include knowledge of the financial aid process, an ability to build relationships with faculty, and an understanding of cultural norms of the middle-class. While research shows that underrepresented students may be less likely to possess this capital, institutional expectations regarding social/cultural capital, specifically among first-generation (FG) students, seems largely unexplored in educational research. The goal of our research is to identify the hidden things FG students are expected to learn in higher education, and how they are able to learn those things. We conducted focus groups of students enrolled in LSAMP (a program that supports underrepresented students in STEM) across 5 universities in the Pacific Northwest over Zoom. Our research focuses on how the hidden curriculum, through the lense of cultural norms and the Federal Application for Student Aid (FAFSA), serves as a barrier to self-identified first-generation students in STEM. Focus groups were conducted by LSAMP students across three universities affiliated with LSAMP and researchers at the University of Washington. Focus groups were recorded and transcribed through Zoom, and later coded and analyzed. Our analysis focuses on identifying common barriers among FG STEM students. In our focus groups, FG students spoke about how relationships with faculty and peers were hard to establish because of their FG background, or because of different/potentially intersecting identities, and also how the FAFSA served as a barrier to them. Our findings support the idea that knowledge of the hidden norms and processes may be expected of students by universities, and that FG students may not possess this knowledge. By developing a better understanding of the experiences of FG students with the hidden curriculum, we can better learn how to support these students.

Microfluidics is the technology of systems in which microscale channels are used to manipulate small quantities of fluids (microliter to picoliter or less). Open microfluidics provides a platform to control the movement of microscale volumes of liquid in open space, making every position more accessible than conventional closed microfluidics. In many applications–including cell culture, chemical synthesis, and high throughput screening–merging droplets is essential for the experimental workflow. For example, merging droplets containing reagents can initiate a chemical reaction, or adding a drug to a cell culture can stimulate cells. In conventional closed droplet-based microfluidics, merging techniques often rely on external components such as merging by electrofusion using electrodes. In other cases, like merging using hydrophilic strips in a channel, the merging method is built into the device and the location of merging must be determined in advance. Therefore, the ability to easily initiate droplet merging in an open microfluidic system would be beneficial to researchers and offer flexibility in experimental design and applications. In this study, I developed an easily accessible droplet fusion technique with the prick of a needle at the liquid interface; my method fuses multiple droplets simultaneously (2-15 droplets). Importantly, this fusion method can be used on-demand at any point in the open microfluidic device and does not require external equipment nor features built into the device. This presentation characterizes the experimental parameters required for successful and controlled droplet fusion and explores the physics behind this phenomenon.

A critical strategy for achieving carbon neutrality is carbon dioxide (CO2) storage and sequestration, wherein CO2 is removed from emissions and stored underground. Current state of the art technologies, such as aqueous amine solutions, suffer from poor stability and recyclability primarily due to their homogenous nature. Metal–organic frameworks (MOFs), extended porous crystalline networks of metal nodes connected by organic linkers, have emerged as an exciting class of potential solid state CO2 storage materials owing to their high internal surface area and facile tunability. Here, we outline the synthesis of an expanded framework analogue of Matériaux de l′Institut Lavoisier-53 (MIL-53) framework functionalized with either ester based crosslinked ligands or bulky tert-butoxycarbonyl (BOC) protected carboxylates or amines, both of which prop open the pores of the framework. Expanded MIL-53 was characterized by powder x-ray diffraction, gas sorption analysis, thermogravimetric analysis, and proton nuclear magnetic resonance (NMR) digestion experiments. These myriad techniques reveal that the expanded MIL-53 framework’s surface area increases with higher incorporation of either ester based crosslinkers or bulky BOC groups. Subsequent thermal removal of the crosslinker or BOC groups to reveal the respective free functional group proceeds without compromising the structural integrity of the framework. Notably, the resultant ‘open’ pore structure is inaccessible without first propping the pores open. Future work will focus on investigating the carboxylate functionalized and amine functionalized frameworks for gas separations and storage.

With the shift towards renewable energy and the promising performance that has been shown by organic-inorganic halide perovskite thin films to harvest solar energy, extensive research efforts have been devoted to further enhancing perovskite solar cell performance. To bring the power conversion efficiency of perovskite solar cells closer to the Shockley-Queisser limit, a high-quality perovskite film with fewer defects is desired. Antisolvent-assisted crystallization is a good way to get compact and homogeneous perovskite films with less defect density. Past studies have demonstrated that additive may be used in both the antisolvent and as a post-treatment to fine-tune perovskite crystallization and passivate defects at grain boundaries or at the surface. Here, we study the influence of multiple guanidinium molecules on the optoelectronic property of wide bandgap perovskite films by using a combination of steady-state and time-resolved photoluminescence (PL). In our testing, we have seen a significant increase in PL emission and PL lifetime of guanidinium molecule treated perovskites, qualitatively indicating that perovskite films with lower defect density is obtained. X-ray diffraction (XRD) and atomic force microscopy (AFM) are used to investigate the effect of these molecules on the crystallinity of wide bandgap perovskite films. From these we confirmed the ability of the tested guanidinium molecules in reducing the defect density of halide perovskite films via antisolvent-assisted crystallization method. This understanding would help us to further push the efficiency of perovskite solar cells and ultimately reach a full carbon-neutral environment.

 Quantum dots are semiconducting nanomaterials that are useful in converting solar energy because of their high absorption and tunable photophysical and chemical properties. They can have various organic ligands bound to their inorganic surface, creating quantum dot-ligand systems useful for charge and energy transfers. When a quantum do is excited by external radiation, an electron inside the dot is promoted to a higher energy level and can be extracted form the quantum dot through the ligands surrounding the dot. We hypothesize that by binding the charge accepting ligand directly to the quantum dot, charge extraction from the quantum dot will be promoted. In my experiments, I am trying to determine the extent of ligand binding to the quantum dot and how this binding is affected by the identity of the binding moiety. To do this, I am synthesizing cadmium sulfiide quantum dots and attaching various ferrocene derivatives through a titration experiment. I analyze each step of the titration experiment for each quantum dot-ligand system with cyclic voltammetry (CV), an electrochemical technique that is sensitive to the diffusivity of the charge acceptor. The resulting CV curve can then be modeled with DigiElch to extract the favorability of the binding of the ligand to the quantum dot. Based on the magnitude of the equilibrium coefficients, we can determine which ligand binds most favorable to the quantum dot and compare this to the efficiency of charge extraction. This research has many applications, from solar energy to medical imaging, and the ability to extract charge outt of the quantum dot in an efficient and quick manner is one worth researching. This research is supported and overseen by Prof. Brandi Cossairt, and graduate students, Micaela Homer and Florence Dou. 

Astrocytes, in addition to neurons, are vital cells in the brain that contribute to maintaining function. Like neurons, astrocytes can also accrue abnormal deposits of proteins with aging and neurodegenerative disease. However, how these abnormal proteins in astrocytes contribute to cognitive decline has not been well-studied as opposed to neurons. Phosphorylated tau is one protein that can accumulate in astrocytes and is often referred to as tau astrogliopathy. Tau astrogliopathy frequently accompanies the pathology of chronic traumatic encephalopathy- a neurodegenerative pathology associated with repetitive head injury. Given this information, we hypothesized that tau astrogliopathy would also occur at a higher incidence and with increased levels of pathology in those with a history of a single traumatic brain injury (TBI), especially those associated with loss of consciousness (LOC). We evaluated and quantified tau astrogliopathy in brain sections from donors with TBI and LOC compared to age-, sex-, and cognitive-status matched controls, from the University of Washington neuropathology research core. Specifically, the density of thorny shaped astrocytes (TSA) and granular fuzzy astrocytes (GFA) in different tissue locations (white matter, grey matter, etc.) throughout different cortical and subcortical regions was quantified. Preliminary data showed a higher density of tau astrogliopathy in cortical sections but not subcortical regions in the TBI with LOC cohort compared to the control group. This supports our hypothesis that there is an association between TBI and tau astrogliopathy; further research is needed to understand the clinical implications of this finding.

The rapid rise of bioanalytical testing has renewed discussions in improving the collection of bacteria through oral sampling. Current diagnostic tests for common respiratory illnesses such as strep throat are invasive and uncomfortable, especially for children. Undiagnosed, these treatable diseases can cause serious damage. The Theberge lab has created the CandyCollect, a saliva sampling device intended to be a child-friendly alternative to current sampling techniques for home and clinical settings. The CandyCollect utilizes candy in the design to appeal to children, a unique component that requires additional testing and standardization to be appropriately implemented. This study explores the intersectionality of safety, design, effectiveness, and ease of application by using candy to increase children's compliance and act as a built-in timer. Our goal is to modify the existing device with these objectives in mind. Several types of candy were made using different ingredients, flavors, and textures, and the interaction of these candies with oral bacteria and saliva was investigated. We engineered the device using rapid prototyping, computer-numerical-control (CNC) milling, and silicone mold development. These methods allow for the flexibility to modify the design of the candy and sampling device. We then designed a survey for a human subjects study for adults (>18 years) to receive useability feedback and adapt the device components. Our analysis of these results determines the variety of candy that is most suitable for large scale use. The findings of this study will offer an improved method for child diagnostics and encourage other industries to redesign traditional sampling procedures. 

The glymphatic system is the waste clearance system in the central nervous system, and it is most active during sleep. This system clears toxic solutes from the brain and include amyloid beta peptides, tau aggregates amongst others. Accumulation of these proteins is the hallmark of many degenerative diseases, including Alzheimer's disease (AD). Therefore, there is high interest in studying the glymphatic system and its role in the pathogenesis of AD. Typically, intrathecal contrast injections are used to study glymphatic flow. However, it is impractical to use this method for studies since they are invasive and need multiple MRIs over almost 24 hours. In this study, the effectiveness of intra-voxel incoherent motion (IVIM) is explored, which is a non-invasive diffusion MRI method that only takes minutes to complete. This procedure measures the velocity and distance of molecules at slow motion over long distances (D*) and fast motion over short distances (D). We hypothesize that glymphatic flow is associated with D*. The glymphatic clearance mechanism is sleep active and even acute sleep restriction or deprivation is known to cause transient impairments in its flow. To determine whether D* is sensitive to glymphatic flow, we compare measurements in subjects with a full night of sleep and in those with sleep deprivation. We expect that D* will be reduced after a night of sleep deprivation compared to that after a full night’s sleep.

 Twelve million US citizens are currently suffering from visual impairment, many of them with late-stage blindness, which is accompanied by a drop in visual acuity, and the inability to recognize faces (CDC, 2022). Currently, few electronic sight restoration devices (SRDs) exist as treatment options for late-stage impairment that are precise in targeting retinal cells. Current SRDs cannot selectively stimulate on and off-center retinal cells – instead, all cells are stimulated regardless of their biologically natural firing pattern. Our research aims to examine whether neural plasticity can aid in overcoming this distortion in sighted individuals, using dichoptic presentation of stimuli that roughly mimics this simultaneous stimulation of on- and off- cells. Specifically, we convolved Fourier filters (F, and it’s contrast reverse complement F′) with images that are contrasted reversed complements of one another (I and I′) to induce a similar coding distortion caused by SRDs. We hypothesized that, through perceptual learning, sighted participants who received training with these distorted stimuli would be able to adapt to these distorted on-and-off cell responses. To test our hypotheses, participants were assigned to one of two groups. While both groups performed an object discrimination task with the distorted visual input, the experimental group did 25 hours of video game (VG) training, while the control group (CG) completed 5 hours of the object discrimination task. Participants in the VG group played a game that is an adaptation of Fruit Ninja, and tested in the discrimination task every 5 hours of video game play. Preliminary results indicate that individuals assigned to the VG group displayed superior performance in the object discrimination task, compared to the control group. Our results indicate that individuals with SRDs may have the potential to learn to decode unnatural visual cell population responses, which could improve their visual perceptions and enhance quality of life.