Bloodborne pathogens are wide spread and can pose risks to health care workers and vulnerable patient populations alike. Conventional diagnostic tests for bloodborne pathogens are costly and time intensive, so fast, affordable, and sensitive diagnostic methods are needed that can be performed under low-resource conditions by untrained personnel. Microfluidic self-digitization technology, developed in the Chiu Laboratory, provides the foundation for such low-cost diagnostics. As undergraduates, we work on the fabrication and optimization of cheap, robust devices used to load samples, as well as dPCR of samples required to detect diseases. As part of a larger research endeavor, we are developing a portable instrument that, in combination with our proprietary microfluidic chip technology, will expand rapid diagnostics to low-resource settings around the world. Expanding diagnostics for bloodborne pathogens will both help prevention as well as monitoring treatment of patients already infected.

The cooling process for aluminum cast molded parts impacts the material properties and quality of the final product.  Understanding what microstructure and properties produced by a given mold is critical for the mass production and design of consumer and industrial parts.  This research analyzes the cooling of a pure aluminum cast molded part under variable corner geometry, in order to predict properties of the finished aluminum product.  This project goal was to create a flexible, three dimensional model of the cooling process for an aluminum cast part, using finite volume analysis. The model takes into account both static and dynamic material states and properties.  The model's goal was to be robust and flexible enough to be utilized for a wide range of material properties, as well as various corner geometries, including chamfer, fillet and a 90˚ corner.  In order to verify the accuracy of the model, and assess microstructural effects, the cast geomtry has been tested with a real mold and aluminum.  Temperature readings for the mold are taken in order to assess the models accuracy.  We predicted that the fillet geometry will cool the slowest of the three geometries, with the chamfer being second and the 90˚ corner being the fastest. With this in mind we predicted that the fillet will have the the greatest cooling continuity, with the chamfer being second and the 90˚ corner being last.

During a 2013 meeting of the Puget Sound Beekeeper’s Association, two major concerns were voiced regarding the rapid demise of bees. One was overwintering loss of honey bees and the other was Varroa mite infestations. The Puget sound area had an average closer to 40%, and overwintering loss for the nation averaged around 30%. This resulted in 2015 President Barack Obama issuing a “National strategy to promote the health of honey bees and other pollinators.” To reduce honey bee colony losses during winter, an effort was made to assess cause of death in honeybees. After the assessment was made, this sparked the creation of the “Mite Busters,” an elite team of students, and community members who shared their passion in beekeeping and biology. The goal of the “Mite Busters” was to assess the cause of death in honeybee populations during the winter months. The Mite Busters conducted an assessment of 15 characteristics of hives in 100 different colonies around Puget Sound in August 2016, and October 2016. Colony death rates were measured after the winter months had passed. The only measurement that allowed us to predict whether the colony would live or die was the mite counts from nurse bees. Before overwintering, colonies that had over 7 mites/100 bees had a 70% chance of overwintering death (30% survival rate). Colonies that had under 7 mites/100 bees mites had a 4% chance of overwintering death (96% survival rate). The results sparked the creation of the Mite Busters, which has put forth a variety of group based mechanisms to help all bee keepers keep healthy colonies together. Specifically, the focus is on treatment plans and methods to decrease infestation rates. The mite busters conclude that fewer varroa mites leads to better overwintering success rates for Puget sound honey bees.

Age-associated diseases, like neurodegenerative disease, cancer, heart disease, and metabolic dysregulation limit healthy human lifespan. In recent years, biologists researching aging and longevity have turned their attention towards maximizing healthspan, the healthy portion of one’s life before the onset of age-related disease. By delaying age-associated diseases, we can fundamentally improve quality of life globally. Natural products and other pharmacological interventions hold particular promise as interventions to extend healthspan and lifespan. We seek to identify novel compounds that extend lifespan using the invertebrate model system Drosophila melanogaster (fruit fly). We have tested an extract made from Pterocarpus marsupium (PME), a tree native to India and Sri Lanka with uses in Ayurvedic medicine. PME extends cellular lifespan in budding yeast, another invertebrate model system. We also tested pterostilbene, a compound found in Pterocarpus marsupium extract. As a positive control for lifespan extension, we are treating other cohorts of flies with rapamycin. Rapamycin is a specific inhibitor of the nutrient sensing mechanistic Target Of Rapamycin (mTOR) pathway, a known longevity regulating cellular pathway. Using multiple fly genetic backgrounds, performed a dose response to identify concentrations of PME and pterostilbene that extend Drosophila lifespan. Through pharmacological methods, we seek to delay aging and minimize human vulnerability to age-induced diseases. Discovery of specific compounds that prolong lifespan is a first step in developing therapeutic methods to delay human aging and health decline.

Blood transfusion is a cornerstone of modern medicine, with a transfusion performed every 2 seconds in the United States. It is critical to accurately determine both patient and donor blood type prior to transfusion, as mixing non-complementary blood types can trigger life threatening reactions. While the ABO antigen system was first described over a century ago by Nobel Laureate Karl Landsteiner, to this day safe transfusion remains burdened by the nuance of blood type. Many of the current blood typing tests over simplify classification and often disregard ABO subgroups, despite widespread recognition of their significance. Moreover, our understanding of the ABO blood types (A, B, AB, and O) is still incomplete, as the full structure and microheterogeneity of these ubiquitous blood group antigens is not yet fully described. This project characterizes the biochemistry of ABO blood types through an interdisciplinary collaboration between UW Bioengineering, Medicinal Chemistry, and Bloodworks Northwest (the regional blood center). Our study employs exhaustive isolation of red blood cell (RBC) membranes from genotyped donors for comprehensive biochemical and biophysical analysis. The RBC membranes are treated with cocktails of enzymes - namely PNGase F, EGCase and Neuraminidase - to cleave glycan structures at specific locations. Reactivity to different antibodies and lectins provides insight into the structure of the glycan antigen. Results have shown that the clinical anti-A antibody binds disproportionally to N-linked associated antigens. These findings inform ongoing mass spectrometric and biosensing work to further elaborate ABO structure and bioactivity, with implications for transfusion and transplant medicine.

The meteorological conditions across the North of Iceland regulate snow metamorphic processes and are therefore the driving factors behind melt-freeze crust formation. The North Atlantic Oscillation (NAO) is a climate system that controls these meteorological conditions. By analyzing the cumulative NAO index over the past two decades, the influence of climate change on Icelandic meteorological conditions can be established: the shifting climate system is stimulating heightened precipitation and increased northern storm cycles. The association of these climate trends with the historical patterns of avalanche cycling in Iceland can help understanding of the causes of melt-freeze metamorphism and can demonstrate the expected effects climate change will have on these processes. According to the cumulative NAO index and the Icelandic avalanche data from 1995 to 2018, melt-freeze metamorphism frequency increased in the early and late months of winter seasons across the North of Iceland and remained less relevant in mid-winter months. The alteration in frequency and seasonality of melt-freeze metamorphism poses challenges to Icelandic communities possibly facing increased risk of slab avalanches and to the vulnerable ecosystems of Iceland. Increased observation and availability of reliable data is paramount to understanding how snow metamorphism will evolve with climate change and consequently what individuals must adapt to.

My guiding question is, “how we can I use storytelling to empower the stories and experiences of the black community in the Central Area that has been displaced through gentrification?” Redlining has historically made it harder for people of color to obtain a mortgage or buy a property in certain neighborhoods, and it continues to exist as gentrification. As tech companies like Microsoft, Amazon, and Airbnb among others continue to expand their presence in the greater Seattle area, rent prices have risen and property owners have started building expensive apartments and living complexes for the influx of workers with a high income. This expansion has displaced people of color who have historically lived in the Central Area. Currently there are stories of resilience in communities that have been displaced by gentrification, but they are often not showcased in the public eye and media outlets. I want to focus on the use of radical storytelling as an act of defiance against erasure, and the role of tech companies in the greater Seattle area in displacing communities. Inspired by the interactive digital stories like “Trump Wants a Border Wall. See What’s In Place Already” in the New York Times or “Microsoft By the Numbers” on Microsoft Story Labs, I hope to create a visual digital story about the ways and means of gentrification, and I hope this story can be used to educate the public about the mechanisms of gentrification and where communities move. By conducting interviews with activists and community members in the Central Area and highlighting their perspective through direct quotes and testimonials, I hope to educate everyone about the strength of communities in the Central Area. My goal is to create a project that focuses on empowering people of color and their stories through community activation.

Pottery is ubiquitous across all levels of civilization, with distinct styles and patterns that can be used to give insight into the nation from which it was crafted. Looking deeper than what the eye can see, the mineral and chemical components can also reveal origins by mapping the components of the pottery piece to likely locations of where that mineral or element is commonly found. Ceramics may have many layers of interest, including the glaze, the slip, and the main body, that can be studied with minimal invasion and destruction of the artifact. Holistic analysis and characterization of these historical pieces requires a multidisciplinary perspective, incorporating fields such as materials science, history, and archaeology. The methods involved in this experiment include x-ray fluorescence (XRF) and scanning electron microscopy (SEM) in order to determine chemical composition and microstructure, respectively, of artifacts (circa 8000 BCE to 1250 CE) found in modern-day Iran. However, not all artifacts are made in the area they are found, hence the need to establish provenance. Preliminary XRF data shows certain samples may contain seashells, owing to their calcium components. This suggests that provenance could in fact be from Iran because Iran is not landlocked. In this we see that provenance is established in part by determining the composition of the artifact and where those materials most likely came from. In attempting to trace the origins of these particular artifacts, a protocol is also developed for mapping other samples and ensuring repeatability while doing so.

The most recent National Vital Statistics Report reports that approximately 9.85% of babies in the United States are born preterm, with 72% of those born late-preterm (at 34-36 weeks of gestation). Using neonatal ferrets at age 17 days old, the Juul lab in the Division of Neonatology at the University of Washington Medical Center has developed a preliminary model of brain injury to mimic late-preterm neonatal injuries. In this species-specific adaptation of the Vannucci Model, the left carotid artery is permanently ligated, along with a temporary (4h) occlusion of the right carotid artery. Ferrets are then exposed to periods of hypoxia and hyperoxia. By looking at data and outcomes from our surgeries, I aim to examine the effects of certain surgical parameters on ferret mortality. These parameters include: time the animal is exposed to isoflurane, the length of surgery, and the amount of time the animal is given to recover between surgery and hypoxia. Aside from mortality, I will also analyze the effects of these parameters on respiratory rate after surgery as well as gross brain injury and data from behavioral testing in an attempt to discern the level of injury in living animals and the most common predictors of death in those that died prior to their determined endpoint.

Drepanosauromorpha is an extinct group of reptiles known from the Middle to Late Triassic (237–212 MA). The clade currently includes seven genera (Avicranium, Dolabrosaurus, Drepanosaurus, Hypuronector, Kyrgzsaurus, Megalancosaurus, and Vallesaurus) that are known from fossils collected in Europe (Italy, UK), North America (Arizona, New Mexico, New Jersey), and Asia (Kyrgyzstan). The first described drepanosauromorph, Drepanosaurus unguicaudatus, was based on a flattened holotype preserving most of a complete skeleton. Subsequently described drepanosauromorphs display the following diagnostic features: the length of the chevrons (ventral spines below the tail vertebrae) is substantially longer than corresponding tail neural spines, the cervical (neck) vertebrae are heterocoelous (saddle-shaped articular surface), the cervical ribs are absent as distinct ossifications, and the chevrons are fused to their respective centra. In recent years, both three-dimensionally preserved partial skeletons and isolated material of drepanosauromorphs have been found across both Europe and North America. These discoveries have helped shape our understanding of the biology and diversity of drepanosauromorphs. However, comparing isolated, three dimensionally preserved specimens to the more complete, yet two dimensionally preserved articulated specimens is difficult due to differences in preservation. Here, we describe a new drepanosauromorph species from the Chinle Formation in Petrified Forest National Park, Arizona based on the left second manual ungual (claw) . Some of the characteristics that distinguish this claw from those of most drepanosauromorphs is its size. It differs significantly from all known Drepanosaurus specimens (like the Italian holotype and the Hayden Quarry Drepanosaurus) because of the ventral placement of the cotyle (articulation surface), the height of the claw, the lack of compression along the pre-axial/post-axial plane, and a furrow along the midline. This new taxon not only highlights unsuspected morphological variation within Drepanosauromorpha, but also helps sheds light on the evolutionary history of smaller-bodied reptiles within Late Triassic ecosystems.

Exosomes are 40-50nm extracellular vesicles released by all cell types, and are involved in a variety of cellular mechanisms including modulation of immune response and cancer microenvironment. Exosomes embed proteins, lipids, and nucleic acids from the parent cells and circulate in abundance in human serum. Recently, exosomes have been shown to have potential application as cancer biomarkers with potentially increased sensitivity and specificity compared to traditional protein or nucleic acid markers. In cancer patients, exosomes are also shed in real time, allowing potential applications in directing therapy, monitoring treatment response, and surveying recurrent disease. Using a known tumor marker, carcinoembryonic antigen (CEA), we examined the role of CEA-specific exosomes as a colorectal cancer biomarker. To establish the methodology, we used CEA-secreting colorectal cancer cell lines LOVO and HT29. We compared exosome isolation methodologies and established an ultracentrifugation-based technique to maximize both purity and yield. Through this methodology, we isolated exosomes from cell-free media and demonstrated that CEA co-localizes with coxasackie-adenovirus receptor (CAR), a senescence-related marker of interest in our laboratory. This finding suggests that tumor-derived exosomes could be used to quantitatively define certain cellular events. We then used archival and fresh patient samples to examine whether the CEA-exosomes could be applied in disease monitoring in patients with metastatic colorectal cancers receiving chemotherapy. Efforts are ongoing to define whether CEA-specific exosomes are tumor specific, and whether exosome conjugate protein and nucleic acid can be further used as novel biomarkers in selective clinical situations.

Dynamic coordination of animal motion depends on the interaction between the neuromuscular system and body mechanics. Changes in muscle length resulting from neuromuscular activation drive the control of locomotion. This project seeks to predict change in muscle length over time based on electrical activity in the complex physiological environment of a living organism. During energetically costly insect flight, the antagonistic shortening of the dorsal longitudinal muscles (DLMs) and dorsal ventral muscles (DVMs) deform the thorax to indirectly power wing flapping. Using electromyography (EMG), we recorded both DLM and DVM activity in vivo during tethered flight of the insect model Manduca sexta. Simultaneously, we captured high-speed video of thorax deformation to measure the change in length of the DLM muscles, which attach directly to the exoskeleton. Unlike other insects, in M. sexta there is a one-to-one relationship between muscle electrical activation and length-wise contraction, allowing direct comparison between these two temporal data sets. Using machine learning, we created a model to predict the amplitude and time course of changes in muscle length 𝓁(𝑡) based on characteristics of the EMG recording. Predicting downstream insect flight mechanics based on EMG data is an exciting application of machine learning which enables us both to better understand the factors influencing muscle length in vivo, and to connect multi-scale muscle structural data through the common link of EMG data. For example, we will predict organism-level changes in muscle length that would have occurred in existing data sets of sub-cellular muscle kinematics based on EMG data collected simultaneously.

Insects use feedback from multiple sensory modalities to control their motor output. Hawkmoths are crepuscular insects that fly in low light conditions, hovering over flowers as they pollinate and feed from them. They use their long and flexible mouthpart, the proboscis, to explore flower surfaces and feed from a tiny nectary opening in these flowers. We asked how moths combine visual and mechanosensory feedback to find the nectary opening in flowers. To test the effect of light level on their efficiency in locating the nectary we combined 3D printing technology to generate artificial flowers, with micro-sensing technology that allowed us to detect the proboscis tip inside the nectary, and computer vision techniques to track the motion of hovering moths at two different light levels; 0.1 lux (moonlight) and 50 lux (dawn/dusk). Using a combination of low light videography and machine vision, we quantified how floral exploration changed between visits, and between the different light levels. We also measured the length of time moths took to find the flower nectary each visit. We found that moths took less time to find the nectary at lower (moonlight) levels compared to higher (dawn/dusk) levels. Hawkmoths are typically active in low light conditions, hence the higher light levels might be adversely affecting flight control. Moreover, preliminary reconstruction of their flight paths suggests that moths hovered over the flower in tighter trajectories under lower light conditions, as compared to the higher light conditions. These results suggest a decreased control over their flight motor output at higher light levels, resulting in reduced hover feeding. These behavioral differences have led us to a series of questions looking at the physiological effects of the different stimuli.

This project examines reproductive output across different wildtype genotypes in the fruit fly, Drosophila melanogaster, and how it correlates with lifespan, activity and age-specific metabolite levels. To answer this question, we used the Drosophila Genome Reference Panel (DGRP), a collection of ~190 fully sequenced Drosophila strains that have been inbred to near homozygosity. Fecundity was measured as the per capita number of adult offspring produced by female flies over 48 hours when they are 4, 8, and 12 days old, using 3-5 replicate vials for each Drosophila strain. We have shown that there is highly significant genetic variation for reproductive output. Reproductive output declines with age in most but not all genotypes. The correlation between reproductive output and lifespan was not statistically significant, suggesting that there is not a direct trade-off between survival and reproduction in this population. A genome wide association study (GWAS) identified statistically significant single nucleotide polymorphisms correlated with variation in reproductive output, although most of them were located in genes of unknown function.

Alzheimer's Disease (AD) is the 6th leading cause of death in the United States. The rate of AD diagnoses has substantially increased in the last two decades. The direct causes behind the initiation of AD are still unknown; however, genetic heritability is known to be a significant risk factor. The goal of our research is to identify the genetic variants that directly influence resistance to the formation of amyloid plaques, which are believed to lead to the initiation of AD. To investigate this idea, we are performing a genome-wide association study (GWAS) using the model organism Drosophila melanogaster. Female flies expressing the human form of amyloid beta (Aβ) are crossed with male flies from each of the 200 lines that make up the Drosophila Genetic Reference Panel (DGRP), a collection of highly inbred lines. The complete genome sequence is known for each of these lines, enabling researchers to carry out GWAS to identify genes associated with variation in any trait of interest. In our case, the progeny of these crosses all express Aβ, but differ from each other with respect to their inherited DGRP genotype. These progeny undergo image analysis to measure the amount of degeneration caused by the aggregation of amyloid plaques in the eyes. Eye degeneration is scored on a five-point scale, from zero, indicating a wildtype phenotype, to four, indicating an extremely degenerated phenotype. Preliminary results show that there is variation in the level of resistance to the aggregation of amyloid plaques among the DGRP lines, which can be accounted for by the genetic variation among these lines. The ability to identify the single nucleotide polymorphisms and the resulting proteins that cause this resistance could be pivotal in identifying methods to prevent the initiation and progression of AD.

Mutations in the ND2 gene (mitochondrially encoded NADH dehydrogenase 2) have been linked to a reduction in efficient energy production, shortened lifespan, progressive neurodegeneration, and mitochondrial diseases such as Leigh’s syndrome. The ND2 gene codes for the production of NADH, a crucial portion of the electron transport chain in cellular respiration. Previous studies have hypothesized that mutations within the ND2 gene are responsible for mitochondrial disease development. However, previous studies have not extensively investigated how genetic variation present in a population might affect the mutant ND2 phenotype. This study attempts to understand how nuclear genetic variation can ameliorate or exacerbate the effects of mutations in the mitochondrially encoded gene, ND2. To model genetic variation in a population, the project utilizes the Drosophila Genome Reference Panel (DGRP), a set of 200 fully sequenced, inbred lines with over 4 million single nucleotide polymorphisms (SNPs) throughout the genome. These SNPs are particularly useful for Genome Wide Association Studies (GWAS). To assess the effects other genes might have on the ND2 mutant phenotype, DGRP lines were crossed with a mutant ND2 line that expresses ‘bang sensitivity’, measured as recovery time following paralysis after being vigorously shaken in a test tube. Recorded progeny recovery times varied significantly among DGRP lines, suggesting that nuclear genetic variants influence the ND2 mutant phenotype. After conducting GWAS, a list of identified SNPs associated with varying recovery times was acquired. With further study, we hope to identify which specific genes interact with ND2, what function those genes have, and whether those genes might be part of a larger regulatory pathway involving the ND2 gene.

Understanding how genetic variation shapes phenotypic variation for complex quantitative traits is fundamental to developing more accurate disease prognoses and therapeutic interventions. Genes that are important in early development contribute to adult quantitative traits, such as height, vision, and health. The fruit fly Drosophila melanogaster is a model organism for studying complex traits, such as aging. Drosophila possesses many well-developed genetic tools and shares evolutionarily conserved age-regulating pathways with our species. One such conserved pathway is the mechanistic Target Of Rapamycin (mTOR) nutrient signaling pathway. Rapamycin is a specific allosteric inhibitor of mTOR signaling that extends lifespan in adult Drosophila melanogaster and delays development in larvae. However, the functional explanation for these effects is incomplete and a genetic association between development and lifespan is unknown. We used the Drosophila Genetic Reference Panel (DGRP), a highly inbred fruit fly population representing natural genetic variation, to measure rapamycin-mediated developmental delay. We used these data to carry out a Genome Wide Association Study (GWAS), and combined our data with data from a screen for the effects of rapamycin on lifespan in the DGRP, also carried out in our lab. GWAS analysis will help us to identify genetic variants associated with rapamycin efficacy and to discover novel variants associated with developmental timing. By connecting lifespan and development genetically, we identified shared candidate genes that modify these two very different molecular genetic programs. Accomplishing this is the first step towards identifying early life biomarkers that are predictive of rapamycin success as a longevity intervention in later years. These pharmacogenomic analyses advance a precision medicine approach where interventions are tailored towards genetic background to maximize human health.

Natural disasters pose a great threat to power systems. They can cause major damage to power lines and substation equipment, resulting in widespread outages. It can then take days to weeks and millions of dollars to restore power to customers. Power system resilience is concerned with reducing the impact of disasters on power systems. The purpose of this study is to evaluate the resilience of one power utility in southwest Washington, the Grays Harbor PUD (GHPUD), to earthquakes, earthquake liquefaction, and tsunamis. This study will consider the likelihood of these disasters, potential effects on the GHPUD’s electrical system and its customers, and possible mitigation techniques. I have collected seismic hazard curves, response spectra, and liquefaction susceptibility data at GHPUD substation sites from US Geological Survey maps and the M9 project. I have also collected data on tsunami inundation depth at substation sites from Washington Geological Survey maps. With this information I have determined which of their substations are most at risk from these disasters. This data will be used to determine possible impacts on substation equipment and to estimate the probability of equipment failure. When completed, the results of this study can allow the Grays Harbor PUD and other power utilities to be more prepared for future disasters and to be more informed of potential resilience improvements.

Sexual dimorphism is a characteristic of many organisms that is genetically encoded and typically studied as a binary trait. Biomedical research routinely categorizes subjects into “male” and “female”, and the resulting data are used to establish sex-specific measures of good health and disease. However, this practice overlooks the existence of intersexual phenotypes and oversimplifies the overlapping variation between sex-specific groups. The phenotypic expression of sex is directed by a complex orchestration of many genes. As such, it is reasonable to consider that there are more than just two discrete expressions of sex, and furthermore that the dimorphism of so-called sex-specific traits resides along a continuum. Metabolomics studies the small molecules that make up all the molecular building blocks in the body, and offers a unique opportunity to quantify sex variation that is morphologically invisible. Doublesex (dsx) is a gene that plays a pivotal role in the sex development of Drosophila melanogaster, and its absence results in an intersexual morphological phenotype. This study models sex in Drosophila melanogaster as a continuous trait by comparing metabolomic profiles for wildtype females, males and dsx null mutants using statistical analysis of metabolome data. While many studies have been conducted to understand the role of dsx in sex determination, to our knowledge no one has attempted to use this novel approach to quantify sex variation as a complex trait. Here we measure over 1000 metabolites in fly samples and test a hypothesis that some metabolites exhibit continuity between male, intersex and female phenotypes. Future work could explore the degree to which these metabolic sexual continuities exist in natural fly populations, and provide a powerful model to study factors that are influenced by sex differences more comprehensively.

Numerous interventions and genetic modifications have been shown to extend lifespan across a diversity of species. However, these studies often assume that extended lifespan is synonymous with extended healthspan. Recent research in the nematode worm, Caenorhabditis elegans, has questioned this assumption, and suggests that increasing lifespan can prolong the frailty associated with old age. This is particularly important for humans, as increasing lifespan without a corresponding increase in healthspan could spell disaster. The majority of healthcare costs are associated with aging-related pathologies, and prolonging life without prolonging health could radically inflate these costs. To parse out the genetic relationship between healthspan and lifespan, we have turned to Drosophila melanogaster, a well characterized model organism for studies on the genetics of aging. We have collected lifespan data as well as multiple measures of healthspan across these genotypes, and found a strong positive correlation between lifespan and healthspan in these flies. This confirms the importance of lifespan as the primary parameter in aging studies, and suggests that genetic interventions increasing lifespan may generally be accompanied by an increase in healthspan.

In 1980 Mt. St. Helens erupted, felling nearby trees into Spirit Lake. Today the remaining logs make up a floating mat covering 20% of the lake’s surface. This unique habitat niche has the potential to host various types of photosynthetic organisms. One such organism is cyanobacteria that has the ability to fix nitrogen from the atmosphere. A previous study on the nutrient budget in Spirit Lake suggested that nitrogen outflow was greater than inflow, and this study aims to investigate the potential role cyanobacteria has on the lake’s nitrogen budget. Our hypothesis is that cyanobacteria growing on these floating log mats, and possibly other benthic habitats in the lake, are the source of the larger outflow of nitrogen. Gathering samples from plankton tows, and artificial substrates anchored to the logs, we counted and calculated the relative abundance of the cyanobacteria compared to other phytoplankton. We found that the average relative abundance of cyanobacteria is about 13.08% across plankton tows and log mats. Over the sampling season relative abundance was low until early July then peaked in early August dropping off slightly over the month. Species richness of phytoplankton also increased significantly in August and remained high to the end of the month. We predicted based on the surface area of the log mats and fixation rates for an oligotrophic lake that the cyanobacteria only accounted for 0.01% of the excess nitrogen output. These results suggest that the dominant taxa on the log mat are not cyanobacteria, and that further investigation needs to be done into other potential habitat that might be more important for cyanobacteria. More extensive sampling needs to be done over the full length of the algal growth season, and the effects of seasonal weather patterns on nitrogen fixation need to be further investigated.

The #MeToo movement has sparked a national conversation about what constitutes sexual consent, and a series of debates have erupted over the actions of famous men like Brett Kavanaugh, Louis C.K., and Aziz Ansari. Popular hits like Robin Thicke’s song “Blurred Lines” have also come under fire for promoting sexual violence by celebrating confusion around sexual consent. At this moment, when norms and expectations around sexual interactions seem to be changing quickly, it is especially important that we have comprehensive and systematic data on how people define sexual consent and interpret ambiguous sexual experiences. Existing studies have shown characteristics of an individual matter when it comes how they conceptualize appropriateness. However, we still do not know to what extent these characteristics matter. This study addresses this gap by answering the question: How do people of varying groups define appropriate sexual behaviors and boundaries? A Q-Method study of over 200 people will reveal how individuals of different characteristics sort scenarios of various sexual interactions into categories ranging from “most appropriate” to “most inappropriate.” Q method is similar to a rank-order techinque and allows for representation or reconstruction of perspectives concerning any given topic of interest. In addition to providing insight about how different people make sense of sexual behaviors, this study shows how Q-sorts can provide a more detailed look at sexual norms than the survey and vignette studies currently used in the field.