The ability to regulate emotion does not develop completely until young adulthood, meaning teenagers are at risk for disorders associated with difficulties in regulating emotions. Identifying one’s emotions is essential for taking active steps towards regulating them; thus emotion differentiation is an essential skill that facilitates psychological well being. Although there have been multiple questionnaires developed to assess emotion differentiation, there are limitations of self-report. Behavioral tasks provide an opportunity to observe an individual’s ability to identify emotions. The Photo Emotion Differentiation (PED) task is a computer task designed to assess emotional differentiation, validated predominantly in adult populations. Participants are shown 20 standardized emotional images and are asked to report the intensity with which they experience each of the 19 listed emotions. The limitation to this method is that it has only been used once in child populations. We aim to validate the PED for use in adolescents by comparing it to a self-report questionnaire [the Levels of Emotional Awareness Scale for Children (LEAS-C)] that assesses emotion differentiation. The instructions for the LEAS-C ask youth to respond to 12 scenarios by indicating how they might feel and how the other person in the scenario might feel. A validated scoring system is used applying specific criteria to the emotion words used in the response. This is an ongoing study and we have currently recruited 14 participants from ages 13 to 16 who will come for a lab visit and complete both the PED and the LEAS-C. A positive correlation between the scores from the PED and LEAS-C will show that the PED is measuring the construct of emotion differentiation and can be used to obtain valid assessment in youth in subsequent studies. With this information, the PED can be used to examine the relationship between pain and emotion differentiation in adolescents.

American Foulbrood (AFB), a disease of honeybee larvae caused by the bacterium Paenibacillus larvae, has global economic significance. AFB spreads through colonies killing the next generation of bees. AFB has traditionally been treated with antibiotics or by burning infected hives and exposed materials. The former method is complicated by antibiotic resistance and bacterial sporulation, while the latter method carries severe financial liability for beekeepers. One alternative treatment is the use of bacteriophages, viruses that infect and destroy bacteria. Bacteriophages are host-specific and co-evolve with their host, unlike antibiotics, thus making resistance and collateral damage a non-issue. Characterizing these phages will be key to future treatments of infected hives. The P. larvae phage Willow, isolated in our lab, is both lysogenic (allow the infected bacterium to survive) and lytic (kill the infected bacterium). Currently, we have confirmed Willow lysogeny in P. larvae strain 3650. This relationship presents a model system for investigation. A comprehensive understanding of the host-pathogen interactions between Willow and P. larvae will aid in the effective targeting of P. larvae in the field. Our laboratory also seeks to determine the relatedness of four P. larvae phages to Willow to further characterize the genes responsible for lysogenic/lytic decision making. In sensitivity assays, lysogens (bacteria with integrated phage) are plated to form a lawn and dilutions of a different phage are spotted onto the plate. An identical wild-type plate is made, and comparison yields plating efficiencies. Plating efficiency determines what degree of protection is offered by the integrated phage. I hypothesize that genetic sequencing will show measurable genetic differences in the putative C1/Cro region of the phages under investigation, and that all genome sequence similarity will correlate directly with established plating efficiencies. Furthermore, I used sequence alignment, product alignment, and dot-plots to illustrate the degree of sequence similarity between phages.

Zebrafish have a higher regenerative potential than mammals, but the genetic differences between the groups that lead to their respective responses are not fully understood. Cross species analyses with mammalian models allows comparison of these genes with their mammalian orthologs to determine which genes show similar or different enrichment during bone regeneration processes. Information from microarray datasets for both rats and zebrafish provide information about the genome-wide transcription during regeneration in each model; the regenerative process in rats has a different timeline than zebrafish, so our lab has developed software to relate the two timelines so that gene expression can be directly compared. Using this information, I am performing two sets of analyses. In the first analysis, I am determining which genes show conserved expression in both models to identify deeply conserved genes essential for regeneration in both systems. In the second analysis, I am finding genes that are differentially expressed between rats and zebrafish during regeneration; pathway analyses of these genes can provide a better understanding of the differences in regenerative response, and potential ways to manipulate this response in both models. Determining the processes that involve these genes can help identify genetic targets associated with important regenerative functions, which can be applied to a mammalian model to potentially improve its regenerative response. Preliminary results for the similarly expressed genes’ ontology of shows involvement in skeletal development, phosphate transport, and organogenesis; the differentially expressed genes’ ontology shows involvement in morphogenesis, peptide linking, and organogenesis. The genes with similar expression affect ECM-receptor interactions and focal adhesion pathways, while the differentially expressed genes are affect nicotinate and nicotinamide metabolism and carbon fixation. Manipulating these pathways in zebrafish can show their distinctive roles in the regenerative process and provide a better understanding of the differences between the zebrafish and mammalian regenerative processes.

More than 40 million people in the United States have or are at risk for osteoporosis, a condition characterized by traits including low bone mineral density (BMD) and high fracture risk. Though genome-wide association studies have identified many candidate genes associated with genetic risk factors, genetic variations that are associated with osteoporosis-related traits, the causal genes underlying these risk factors remain undiscovered. My research centers around developing tools to assess bone morphology in a zebrafish model to identify specific genes that cause osteoporosis or other skeletal abnormalities. Because a trademark characteristic of osteoporosis is expanded bone diameter due to accelerated bone remodeling and increased resorption in the endosteum, I have developed tools to assess bone expansion in zebrafish vertebral structures. By using integral calculus and basic machine learning with the R programming language, I developed a predictive model for calculating approximate diameters for the centrum foramen, the hole in the zebrafish vertebral body. As a more direct alternative, I have also developed a program using image analysis tools in MATLAB that identifies the foramina of the centra, neural (superior) arches, and haemal (inferior) arches in binarized microCT stacks of zebrafish skeletons and calculates the cross-sectional area of each foramen. I am using these tools to retroactively analyze previously scanned mutant zebrafish to identify genes that have phenotypes consistent with abnormal foramina of the vertebral body and arches. I have determined that mutants with the bmp1a and plod2 genes knocked out separately have expanded centrum foramina. After compiling and analyzing a zebrafish data archive with data from other previously imaged mutant samples, my results will indicate previously undetected phenotypes. This data will aid in my lab’s efforts to determine the causal genes underlying osteoporosis genetic risk factors. This research may lead to discoveries that are used in future osteoporosis gene therapies.

Plants are affected by various abiotic and biotic stressors such as pollution, high salinity, drought, and pathogens which can inhibit growth or cause disease. High salinity, a type of abiotic stress that decreases crop productivity and quality, is especially widespread with nearly half of the world’s cropland facing salinity stress in 2010. This is problematic because there are very few plants that can tolerate high levels of salt and the process of remediation is water and energy intensive. However, endophytes, the beneficial bacteria that live within plants, have shown potential in helping plants tolerate these stressors in a more natural way either by directly reducing the stressor or indirectly by modulating the plant’s response to the stress. The main goal of this study was to isolate and test endophytes to determine whether they colonize other plants and help these plants tolerate high salinity conditions. In this study, a total of 15 salt tolerant endophytes were isolated from pickleweed and wild wheat growing in a marine estuary. These strains were then tested on bush beans and poplar to test salt tolerance conference. There were visible signs of higher stress tolerance in bush beans inoculated with endophyte SSP1 and poplar inoculated with SSP8. The results for the remaining endophyte strains are pending. By improving plant growth under abiotic stress, these bacteria will help promote sustainable agriculture practices and bioenergy production.

Microbes that live within plants, called endophytes, are being heavily researched on their ability to assist host plants in processes from nitrogen accumulation to drought tolerance. Two endophyte strains named WP5 and WP9 are known to colonize Populus trees. Previous research has shown that the presence of WP5 in a host plant allows for greater colonization by WP9 subsequently. This research is directed at replicating these results with more robust molecular biology techniques. Methods for experimentation include the growth of the endophytes in selective media and varying the optical densities of these liquid cultures before inoculating the poplar clones. The plants co-cultivate with the inoculum for 24 hours, at which point they are removed, washed and placed in limited nutrient media. After removal from the inoculum as well as at 7 and 14 days hence, the host plants will be sampled by performing genomic DNA extractions and subsequently analyzed through Digital Droplet PCR to quantify endophyte presence. Additionally, these strains have been marked with fluorescent tags to enable imaging under a microscope. The two endophytes were labeled with different colors, one red and one green, so that they could be visualized concurrently. Along the same sampling timeline, root samples will be taken to image through microscopy in order to visually investigate the colonization process of the two strains. The results of this research will help to shed light on the colonization abilities of these strains, and allow for the optimization of bio-fertilizers comprised of endophytic consortia.

One of the most significant problems facing modern agriculture is climate change. Plants thrive best within a fairly narrow range of temperatures. Outside of that range they have significantly reduced crop yield and significantly increased mortality. This imposes limitations on where certain crops may be grown. Due to rapidly growing populations, the industry must be allowed to expand into new regions, but climate change is reducing available regions. One possible solution is amplified heat tolerance due to symbiosis with endophytes. Endophytes are symbiotic microbes which live in the intercellular space within plants, and which may be used to improve plant fitness through stress tolerance, nutrient supply, and many other mechanisms. We chose a poplar tree which likely hosted beneficial microbes to alleviate heat stress due to its harsh environment, and have been working to isolate the relevant endophytes. I am using a plant-based isolation procedure using species such as rice and kale. By exposing the plants to the endophytes and then to heat stress, I assure that the endophytes have a broad host range because they must be able to survive in more than just their host plant, and I allow the plant to choose the most helpful endophytes to alleviate stress. Through multiple repetitions of this isolation procedure, I can increase the presence of heat-tolerance-conferring endophytes within the microbiome. These endophytes may eventually be used to expand growth into regions which are outside of conventional temperature ranges, or to remain in current regions in which temperatures are increasing.

Glutathione S-transferase (GST) is an enzyme that is present in most organisms. Its primary function is the detoxification of xenobiotic compounds. In mammals, some GST isoforms have a role in modulating the MAPK signaling pathway. The GST protein from Schistosoma japonicum (26 kDa) is also an important tool used in biochemistry labs as a tag for the isolation of proteins via affinity chromatography. Reduced glutathione (GSH) is a substrate for GST that binds to its G-site with a high affinity, and this interaction can be exploited to purify GST-fusion proteins on agarose beads containing a GSH moiety. In the research presented, GST was expressed in E. coli, purified, and dialyzed to remove GSH ligand completely. The protein concentration of the purified, dialyzed GST sample was quantified using Qubit™ fluorescence spectroscopy. Isothermal titration calorimetry (ITC) was utilized to measure the dissociation constant and thermodynamic properties of the binding of GSH to GST. ITC is a highly sensitive analytical method that monitors changes in heat produced from noncovalent chemical associations. In order to obtain accurate ITC measurements, various concentration ratios of GSH/GST were explored. Quantifying the binding affinity and thermodynamic properties of GSH binding with GST provides useful information for investigators who use GST as a fusion tag or who are interested in reactions between the GSH-GST complex and its substrates.

In the Pacific Northwest the Endangered Species Act (ESA) protects wild salmonids from commercial fishing. The current commercial fishing gear, including gill nets but not limited to, disrupts the recovery of these species because fishermen can not selectively harvest the hatchery fisheries without wild salmonids as bycatch, which have high mortality rates. Once ESA quotas are met this can effectively shut down commercial fisheries. The exploration of alternative fishing tools that can select for certain species will lower bycatch mortality rates of ESA species, and in turn allow commercial fisheries to operate longer. On August 26th through September 29th of 2017 Wild Fish Conservancy conducted follow up research, to a 2016 pilot study of Pound nets, in the Lower Columbia River Sub-Basin. Post release survival rates were evaluated in a modified stock selective pound-net. Using Mark Recapture methodology, with a Passive Integrated Transponder (PIT) tags, and genetic clippings for later analysis. Survival rates of control specimen to treatment specimen were captured as they traveled past dams upstream. Data analyzed were total catch, catch per unit effort and covariates of recapture probabilities. The preliminary results show that fishing with stock selective nets can effectively target hatchery fisheries while successfully releasing ESA listed species, reducing mortality rates. In 33 days WFC and a local fisherman captured and released 7,129 salmonids with a post release survival for steelhead and trout ( Oncorhynchus Mykiss) of 94.0%, and 96.6% for Chinook salmon (Oncorhynchus Tshawytscha) listed as ESA species. Hatchery fisheries of these species along with coho salmon (Oncorhynchus kisutch) were effectively selected with viable commercial quantities. Future subset data of genetic clips and a Jolly-Seber analysis will give more precise information of these post-release survival estimates.

In the population of bottlenose dolphins (Tursiops aduncus) in Shark Bay, Australia, groups of two or three adult males form long-term alliances that sequester, harass, and intimidate adult females, presumably to increase their chances of mating success. Costs that males inflict on females include physical injury, changes in home range and habitat use, reduced foraging, and changes in calf care. Although altered female behavior is evident during association with males, the direct impact males have on female behavior is not entirely clear. That is, male behavior and female responses to such behavior during consortships have not been explicitly documented. A long-term study has collected detailed behavioral data on the Shark Bay population since 1988. Using this dataset, this project will quantify the rate of male aggression directed at females and how female activity budgets and foraging tactics change in response. Preliminary work indicated that rates of received aggression were higher for cycling females than non-cycling females, and higher when females were in the presence of more than one male, potentially confirming that males use aggression to coerce reproductively viable females. Females also spent less time foraging when in the presence of more than one male, hinting at potential costs to the female owing to loss of food. Because females have highly specialized foraging tactics, changes in foraging behavior and home range during prolonged or repeated consortships could impact female condition.

It has long been known that certain species possess the capacity to regenerate bony appendages following amputation through a process called epimorphic regeneration. For instance, zebrafish possess the ability to regenerate their tail fin bones. Early regeneration involves the formation of a blastema, similar to the blastema that mediates limb regeneration in salamanders. After the blastema forms, the bone regeneration process resembles the bone developmental process in humans. Thus, a better understanding of epimorphic regeneration holds promise to enhance our understanding of regenerative biology, allow for medical advances in bone tissue engineering, as well as increase understanding of the skeletal developmental processes. A challenge in understanding the regeneration process is the inability to immobilize fish to generate time lapsed images of various stages of regeneration. Typical methods for anesthesia in zebrafish only enable 10-20 minutes of sedation. Several studies (including those by our lab) have developed specialized methods to do long-term imaging with the use of Tricaine Methanesulfonate and Benzocaine. However, both anesthetics are sodium channel inhibitors, which inhibit the regeneration process itself. In order to circumvent this problem, we designed a chamber for lower anesthetic plane imaging with a restraint system, as well as a glass-bottom window to facilitate imaging. The chamber is coupled to peristaltic pumps so water and anesthesia can flow in and out. In pilot studies we have found the zebrafish quickly acclimate to the chamber, and have remained in the chamber for two hours. We have been able to image sp7, NADH and birefringence simultaneously for the first 2 hours of regeneration and have found stability in these signals over time. Our studies indicate that this long-term imaging chamber may allow us to see details of dynamic processes that unfold during bone regeneration, which currently can only be seen through snapshots of short-term imaging.

How is star formation affected by its environment? How big is the effect of having differing metallicities during the star forming process? The goal of this research is to study star formation in low metallicity environments, which are well represented by dwarf galaxies. For this project, we used the Atacama Large Millimeter Array (ALMA) telescope, at an angular resolution of about 0.5 arcseconds (about 66 lys), to observe the 12CO (115 GHZ) distribution in the galaxy Henize 2-10 (He 2-10). He 2-10 is an irregular dwarf galaxy about 30 million lightyears (lys) away, about 1 kilolightyears (kly) across, and has a mass of about 10 billion solar masses. It has a high gas to dust ratio, is star forming, and has a low metallicity of about 12+log(O/H)~8.3. Additionally it contains a supermassive black hole candidate of about 1 billion solar masses, which could have significant dynamical interactions with the molecular gas. We created a zeroth moment map which we used to estimate several properties of the galaxy: including a molecular gas mass of about 38 million solar masses, an observable area of about 1850 square klys, and a molecular gas density of about 3.7x10^(-20) grams per cubic centimeter. We also created multiple channel maps which provide preliminary results that indicate the presence of at least 10 giant molecular clouds within He 2-10.  With what we have done so far, we will be able to compare our results to known giant molecular coulds in the Milky Way Galaxy, and begin to better understand the relationship, if any, between star formation and star forming environments. 

Single electron devices (SEDs) are devices that can isolate individual electrons along a conducting path. SEDs have many proposed applications including their use in metrology, and quantum information science. However, there are many barriers that must be overcome before these applications are realized beyond the proof of concept experiments currently being performed in academic research labs. Our group’s work focuses on pathways to overcoming some of these barriers including the issues with material properties and device stability. My contribution focuses on data analysis of SED transport measurements. These analyses produce various metrics for both the SEDs under test as well as the measurement system probing them. They include determinations of charge offset drift, a metric for long term device stability, as well as electron temperature a limiting factor in magneto spectroscopy measurements.

Cancer is the 2nd leading cause of death in the United States. Of these cases, 6-7% are pancreatic cancer (PC), yet this disease is ranked 1st in mortality because what causes PC and how it manifests is still relatively unknown. Early detection is difficult and in a majority of cases, patients are diagnosed after the cancer has progressed to final stages. For the last 7 years, the Human Photonics Laboratory (HPL) has been dedicated to early detection and diagnosis of PC through the next generation 3D pathology (and all aspects of its infrastructure: 3D microscopy, 3D reconstructions/supercomputing, millifluidic device development/whole tissue processing, clinical evalution/validation). For PC, cell and tissue specimens which have been imaged in 3D and reconstructed in an advanced 3D visualization software (Amira) require an appropriate gray scale and RGB color scheme to determine accurate cancer diagnoses. Ideal and non-ideal samples may then be passed onto collaborating pathologists for clinical evaluation and validation. This research project seeks to satisfy three primary aims: (1) properly match the color metrics/scheme of the raw optical 3D microscope datasets to 3D computer reconstructions and analyze (qualitatively/quantitatively) the gray scale/RGB color histogram between normal/cancerous (human) pancreatic samples, (2) compare/contrast the pathological metric known as the nuclear-to-cytoplasmic (N/C) ratio between a small sample of normal/cancerous specimens, (3) choose 5-10 ideally processed/matched specimens and submit to pathologists for clinical evalution. The outcome of this project is expected to accelerate the diagnosis of PC.

The trio of crops that are responsible for the bulk of human nutrition are pollinated by wind. Wind pollination has evolved repeatedly from insect pollination in angiosperms, however the mechanism for these shifts, such as the specific morphological traits and genes involved, has not been explored. Thalictrum (in the buttercup family Ranunculaceae) is a genus of herbaceous perennials with considerable floral diversity and multiple transitions to wind pollination in closely related species, making it an ideal system to study pollination syndrome shifts. Insect-pollinated species have larger, showier flowers with pigmented organs, while wind-pollinated species have green floral organs, exserted carpels and pendulous stamens. Here, I set out to characterize and quantify floral traits in wind and insect-pollinated species in Thalictrum to: 1) Test whether there is a suite of floral traits associated with wind pollination syndrome; 2) Prioritize the traits that contribute the most to pollination syndrome; and 3) Find the genetic basis of these traits. Flower scans from live plants, in addition to specimen from the University of Washington Herbarium, were used to measure floral traits using imageJ in 17 species across the Thalictrum phylogeny. Multivariate analysis of floral traits using Principal Component Analysis, showed that species cluster by pollination syndrome. Correcting for phylogenetic relatedness resulted in most of the variance being explained by the first principal component, clustering species by pollination syndrome even when they are distantly related. This evidence suggests that a specific combination of traits has been independently selected via convergent evolution in the transition from insect to wind pollination in this group. Next, I plan to conduct reconstruction of ancestral character states to track trait evolution and identify those that most closely correlate with shifts in pollination mode, followed by expression analysis of candidate genes.

With the spread of large digital painting collections, the demand for automatic theme classification has risen in both academic and commercial fields. Many researchers have investigated various techniques to implement automatic painting classification and developed several approaches to improve classification accuracy. SURF is one of the most commonly used local invariant feature descriptors for painting classification. However, the common method of classification based on traditional SURF local feature description makes the color feature information not comprehensive. Also, the feature space is high dimensional and sparse which will result in low classification accuracy, data redundancy and a time-consuming process. To overcome this drawback, we suggest a new method of classifying painting styles with bag of words (BOW) model based on the RGB-SURF algorithm. First, split RGB channels into separate images for each painting. Then, independently calculate key points and descriptor of each RGB channel using SURF and combine descriptors of each channel to obtain overall RGB-SURF feature for each painting. This approach is to compensate the loss of color feature brought by traditional SURF descriptor which mainly treats colorful images as gray images. Next, construct the visual vocabulary by reducing the number of features through quantization of feature space using K-means clustering to obtain BOW model. The histogram described by appearance frequency of the visual words is used to represent the content of the image. As a result, every image is viewed as a bag full of visual words. Finally, establish the support vector machine (SVM) classifier based on radial basis function (RBF) with the data above for training and testing. Compared to classification method based on the traditional SURF feature descriptor and other painting classification approaches, BOW method based on RGB-SURF algorithm shows the highest average classification accuracy, which means this method produces the most consistent automatic classification results with manual classification.

At one point or another, every student is faced with some sort of academic failure that can in turn have negative impacts on self-esteem or future academic performance. Being able to overcome such obstacles requires resiliency and the ability to view failure as a learning opportunity. Growth Mindset (GM) interventions aim to shift a student’s perception of intelligence as a quality that can be developed over time and enhance their approach to overcoming barriers. Originally, the GM was developed as an evidence-based intervention to be delivered by trained professionals. However, bringing this intervention into the real-world calls for a more feasible and accessible model. To bridge this gap, the current study utilizes the role of teachers as a valuable resource in building capacity within schools to attain sustainable, long-term goals regarding student success. The purpose of our research is to explore how a GM intervention delivered by teachers affects students’ beliefs about the brain’s ability to change (neuroplasticity). This project utilized a randomized control design with longitudinal follow-up to evaluate the efficacy of the GM intervention in comparison to curriculum as usual delivered in a rural district in the Pacific Northwest region. At two separate time points, middle and high school students completed an online self-report survey that assessed three constructs: theory of intelligence (whether intelligence can be changed), effort beliefs (the relationship between effort and outcomes), and learning goals (goals towards improving academic abilities). We hypothesize that students assigned to the intervention would show more positive implicit attitudes towards malleable intelligence, beliefs about effort, and learning goals. By understanding how students view themselves within an educational context, we can improve the measures taken to further engage and empower students. Future research should evaluate the quantitative outcomes of academic performance (i.e. grade point average) in relation to a GM intervention.

Previous research on JNK-mediated stress signals demonstrated that stem cells in the posterior midgut of Drosophila Melanogaster only undergo compensatory proliferation or apoptosis. However, our group discovered that the stem cells can also undergo the process of basal extrusion and dissemination, resulting in the cells being eliminated from the tissue into the hemocoel, the blood containing intertissue body cavity. The JNK signal promotes the cells to exit the epithelium of the gut, move through the muscle layer, and be released to the hemocoel, which resembles the process of metastasis in human cancer. In order to understand the mechanism of this extrusion process, we carried out an RNA Interference (RNAi) screen and sought to find genes that are necessary for the stem cell extrusion in the JNK activator, HepCA, expressed flies. We used the ESG-GAL4, UAS-GFP, TUB-GAL80TS(EGT) genetic system to study the knockdown effect from the RNAi of each gene. We selected 215 lines of kinases and phosphatases of flies to test if the knocked-down gene results in suppression of cell elimination by the JNK stress signal. After 4 days of inducement, which is the sufficient time for the JNK signal can promote complete extrusion of the intestinal stem cells, the intestines were dissected, fixed, mounted, and examined with a fluorescent microscope for any presence of stem cells. Through this screen, we could find 33 lines that had strong suppression of cell elimination, 39 lines that had a moderate effect. Our results suggest that the knocked down genes with strong suppression of cell elimination are involved in the mechanism of basal cell extrusion, and future research dictates an investigation into the molecular function of each of these genes.

Nuclear fusion power is one of the best candidates for the next generation of energy. It has many desirable properties such as producing more energy than fossil fuels per kilogram of fuel, zero carbon emission, and producing no long-lived radioactive waste. Therefore, nuclear fusion power is worth pursuing and it has been studied for decades. One of the critical issues in nuclear fusion research is the impurity contamination. The impurities released from plasma-facing components through various plasma-wall interactions can lead to dilution of the fusion fuel. Therefore, it is very important to study impurity content and behavior. The impurity level is an important parameter in the research of magnetically confined plasma and can be quantified by the ion effective charge, Z_eff. Ion effective charge can be derived from bremsstrahlung emissivity from the visible spectrum radiation of plasma. The objective of this project is to set up a calibrated system that yields high precision in measuring bremsstrahlung emissivity. It is important to absolutely calibrate the system because impreciseness of bremsstrahlung emissivity measurements gives the inaccurate values of Z_eff. In our calibration, a Stabilized Halogen Light Source (SHLS), integrating sphere, and a photodiode are used. We collimate the light from SHLS and send it to the integrating sphere through fiber optics. The light in the integrating sphere is captured by a photodiode and a telescope and is transferred to current and voltage signal respectively. Our goal is to get the correct calibration factor that will give us correct values of bremsstrahlung emissivity measurements.

This project addresses the problem of community membership detection on social media using only text features in a scenario where a small number of positive labeled examples defines the community. For example, if we are given the tweets of chess grandmasters, then the community is defined as chess grandmasters, and the model we propose should identify people likely to be chess grandmasters. We introduce user embeddings (dense vector representations of the users) trained on an unsupervised proxy task: user re-identification. Experiments with 16 different communities show that the resulting embeddings are more effective for community membership identification than common unsupervised representations, measured both by average AUC and 1/MRR measure.

Predators exhibit top-down effects on plant communities by altering the abundance and behavior of their herbivore prey. Disturbance regimes such as wildfire may impact the strength and nature of these interactions and their corresponding effects on plant communities. In 2015, wildfires burned through areas in northeastern Washington impacted by the recolonization of gray wolves (Canis lupus) and inhabited by their two main prey species, mule deer (Odocileus hemionus) and white-tailed deer (O. virginianus). We are using data collected in burned and unburned areas across wolf-impacted and wolf-free sites to explore the relationship between recent wildfires and the effects of predators on plants. Data on plant species presence, percent cover, and browsing extent within each plot and associated controls will provide an index of browsing intensity and plant species selection by deer. Our preliminary analysis contrasts plant percent cover as a function of fire, wolf-presence, and measured landscape variables. Our findings will yield a better understanding of the top down effects of predators like wolves in areas like the American West that are predicted to be increasingly affected by wildfire.