Individuals with impaired finger function are commonly prescribed a wrist-driven orthosis which utilizes wrist movement to open and close the fingers. However, if the individual has weak wrist extensors and flexors in addition to weak fingers, this device becomes obsolete. While multiple prosthetic devices are available to amputees, options for orthotic devices are limited. The purpose of this research is to adapt elements of successful upper limb prostheses into an open-source orthosis made with 3D printed and off the shelf materials for an individual with unilaterally impaired hand and wrist function. We continue to draw inspiration from body-powered prostheses, where the motion of other joints, such as rotation of the elbow, is used to control artificial hand motion. Gaining hand motion through the use of this device will allow users to perform daily tasks independently and with improved performance. We first created a series of prototypes to identify task specific designs. An optimal design will utilize elbow or shoulder movement to operate a low-profile hook positioned under the palm while also stabilizing the wrist and fingers which are flaccid. Input from practitioners aided in optimizing the design and process. In order to augment design acceptance, our research included user testing and feedback. Once a design was finalized, we resized the device to fit our participant. The participant then went through a series of hand functional tests which compared their ability to complete an assortment of tasks, such as lifting and moving small blocks, with and without the device. These results as well as user feedback assisted in further improvements to the overall design of the device. After completing our design, the orthosis was made open-source to make it both accessible and low-cost, while allowing users and makers to further improve upon the device.

According to the Centers for Disease Control and Prevention, diarrheal diseases are the second leading cause of death in children under the age of 5 globally. Cryptosporidium and Giardia are two microscopic parasites that cause diarrhea, infecting both humans and animals. The current gold standard field method for collecting water samples for parasite testing (Environmental Protection Agency (EPA) 1623), is not practical for remote sample locations as it requires 10-L of water to be kept on ice during transport to testing facilities. A pilot study by the UW Center for One Health Research will implement a new water sampling system, known as Bag-Mediated Filtration System (BMFS), to look at how these parasites impact low resource communities. My goal was to determine if BMFS could be used in conjunction with EPA 1623 to give recovery rates consistent with the current EPA 1623 method. I went to 4 different locations in Washington to retrieve surface water samples using the BMFS kit. Sites were chosen based on the likelihood that there would be parasites present: sources with the possibility of animal waste and areas with turbid water. The environmental samples, along with 10 parasite-spiked laboratory samples were analyzed using the EPA method - after filtration using the bag. Parasite numbers were measured as oocysts per liter using immunofluorescence, and recovery rates of spiked samples were compared to acceptance criteria from the EPA. This study will be useful to water quality researchers working in rural or remote field sites, or areas where climate conditions make sample storage challenging.

The Bengal Fan is a cone-shaped submarine deposit that contains the sedimentary record of the collision between India and southern Asia, the formation of the Himalayan mountain range, and the development of one of the largest deltas in the world. Erosion of different rock types as the Himalayan crustal blocks were uplifted has produced variations in sediment composition within the Bengal Fan. This study focuses on using frequency-dependent magnetic susceptibility combined with optical and electron microscopy to identify magnetic iron oxides and sulfides in core samples taken during International Ocean Discovery Project Expedition 354. I will identify differences in oxide and sulfide mineral assemblages through time and trace their provenance. This data can then be used to track sediment sources that contributed to the creation of the Bengal Fan and uplift processes that created the Himalayas.

In order to successfully invade and survive within a host cell, pathogens such as the bacteria Shigella flexneri have to suppress the host cell’s immune response. To do this, Shigella flexneri inject bacterial effector proteins into the host cell that hamper the host cell’s ability to detect and respond to invasion. One such protein is IpaH4.5, a bacterial E3 ubiquitin ligase, which hijacks the host cell’s ubiquitylation machinery to transfer ubiquitin, a small signaling protein, to a substrate. Ubiquitin signaling impacts all aspects of eukaryotic cell biology. Often modification of a protein by ubiquitin serves to mark protein for destruction. IpaH4.5 targets proteins involved in the host cell’s immune response, dampening the host cell’s ability to respond to invasion by Shigella flexneri. I am investigating IpaH4.5 and its interactions with both host substrates and the host ubiquitin machinery. After sub cloning out the various domains of TbK1, a known substrate of IpaH4.5, I will perform ubiquitilation assays in order to determine which domain of TBK1 is polyubiquitilated, indicating that IpaH4.5 interacts with this domain. Then, this domain can be used for structural and mechanical analysis of IpaH4.5, such as determining how mutations in IpaH4.5 affect ubiquitilation through biochemical assays. Understanding how IpaH4.5 binds to and interacts with its substrates will increase our understanding of how Shigella flexneri dampens host immune response as well as help us better understand the mechanisms of bacterial E3 ubiquitin ligases. Since IpaH4.5 functions differently than eukaryotic E3 ubiquitin ligases, increasing our understanding of its mechanisms could allow us to use it as a target for future drug development. Finding new targets for drug development is becoming increasingly important with the spread of antibiotic resistant bacteria.

The mineral composition of marine sediments is an indicator of recent climate change. Long-term changes in global climate over the past 40 million years are likely both a cause and an effect of the rise and erosion of the Himalaya. The Ganges and Brahmaputra rivers have deposited most of the Himalayan sediment in the Bengal Fan. Sediment cores samples collected from the International Ocean Discovery Program Expedition 354 to the Bay of Bengal were analyzed using visible and UV diffuse reflectance spectroscopy to determine changes in mineralogy. A focused analysis of a set of ship-board data of the sedimentary record of the last glacial cycle (100,000 years),using non-negative matrix factorization, showed three endmembers corresponding to different mineral assemblages: one with a blue spectrum (peak wavelength of 400 nm), a second with reflectance in the 400-500 nm wavelength range, and the third with a red spectrum. The mineral content of these endmembers will be determined by comparing their reflectance to the NASA library of mineral spectra. Changes in composition through time will be compared to known climate proxy records over the same time period to determine new mineral climate proxies. These climate proxies can contribute to a better understanding of the relationships of Earth’s climate system to sediment sources and weathering.

High aspect ratio nanostructures have been targeted for use in nanoscale electronics and photonics integration, as well as energy storage and conversion due to quantum confinement effects and high curvature. For instance, 3rd generation solar cells based on Si semiconductor nanowires exhibit improved absorption and current generation due to high aspect ratio and quantum confinement, yet widespread adoption of these technologies is limited due to lack of scalable synthesis methods. Solution-liquid-solid growth of semiconductor nanowires is a cheap, potentially scalable, environmentally-benign process that uses bismuth nanocrystallites as a growth site. Synthesis of Bi nanoparticles, however, is currently achieved by using costly and lethal reagents, in a technically difficult process that is sensitive to O2 and H2O. Furthermore, storage of these reagents is a large concern due to their volatility and the particles themselves tend to oxidize extremely quickly.  In this work, we evaluate a one-pot reaction for the production of bismuth nanoparticles using benign Bi2O3 as a precursor. We observe that the size of these particles depends directly on reaction time, and we hypothesize particle synthesis occurs through nucleation-and-growth process. In addition, these Bi nanoparticles show a remarkable resistance to oxidation after storage for weeks in an atmospheric environment. We speculate surface is passivated with a fluoride shell as a synthesis byproduct, which inhibits oxidation. We have studied these particles in different ways including SEM and XPS to determine the size and composition respectively. Our synthesis uses safe precursors and produces particles which are much more stable over the long term; this has the potential to make the use of bismuth nanoparticles a much more viable process and increase our understanding of bismuth on the nanoscale.

In the aging community, our ultimate goal is to lifespan and healthspan, the period of time that an individual lives healthily. Previous studies have found that aging results in decline of heart functions and increases prevalence of cardiovascular disease. Characteristics of cardiac aging include enlargement of the left ventricle, impaired diastolic functions, and reduced myocardial performance. Oxidative stress has been implicated as one of the mechanisms underlying cardiac aging. SS-31 peptide, a tetrapeptide that targets the inner membrane of the mitochondria, has been shown to interact with cardiolipin and enhance the electron carrying function of cytochrome c, an essential component of the electron transport chain. SS-31 peptide also limits oxidative damage to cardiolipin, a phospholipid that is almost exclusively located in the inner mitochondrial membrane, by reducing peroxidase activity of cytochrome C. SS-31 treatment has been shown to protect mitochondria in pressure-overload induced heart failure and oxidative injury in other tissues. In this study, we performed echocardiography and treadmill running and showed that 8 weeks of the SS-31 treatment improved diastolic function, myocardial performance, and enhanced exercise endurance in old mice. Using quantitative real-time PCR, I am assessing the gene expression changes regulated by the SS-31 treatment. Understanding the mechanism of how SS-31 improves cardiac aging will provide insight on potential therapies to improve cardiac health in the elderly populations.

Antibiotic resistance in bacteria is rapidly rising and our garrison of effective drugs keeps dwindling. As the creation of new antibiotics is incredibly time-consuming and expensive, it’s crucial that we slow the rapid evolution of drug resistance to prolong the effectiveness of our current drugs. Recent studies suggest improving current drug cycling practices by exploiting a phenomenon known as collateral sensitivity, where resistance to one drug leaves bacteria more sensitive to a second. By selecting pairs of antibiotics that exhibit collateral sensitivity, this method causes one drug to become more effective at abolishing bacteria after resistance to another drug has occurred. However, it is not known if collateral sensitivity profiles are maintained after further evolution of the bacteria; information that is crucial if we want a long-term method of combating drug resistance. Through our experiments, we aim to test the null hypothesis that collateral sensitivity profiles do not change over evolutionary time. To do this, we first isolated an array of Gentamicin-resistant Escherichia coli that exhibit collateral sensitivity to Colistin. Then we evolved our resistant bacteria for ~200 generations and measured the minimum inhibitory concentration (MIC), the concentration of drug that inhibits bacterial growth, for both drugs. By comparing the MIC values before and after our evolution experiment, we can determine if collateral sensitivity changes. If collateral sensitivity increases after evolution, collaterally sensitive drug cycling treatments could prove to be more effective than we already assume. But if collateral sensitivity decreases, the efficacy of this style of treatment may be reduced, which is important to know when designing drug cycling treatments. Knowledge of collateral sensitivity patterns will influence the way we treat patients and combat future multidrug-resistant bacteria.

There is no known therapy for the loss of cardiac function associated with aging. Aging has been long associated with oxidative damage from reactive oxygen species (ROS), which are mostly produced at the mitochondria. In mammalian cells, catalase is an enzyme located in peroxisomes that breaks down damaging hydrogen peroxide. Methods that target catalase to the mitochondria, where most of the oxidative damage occurs, have been shown to increase life span and attenuate age-related pathologies in mice. Adeno-associated virus (AAV) has been used for gene transfer in mice and humans for decades with no adverse effects. We are investigating if the presence of AAV-mCAT leads to an improvement in cardiac function, the percentage of cells in each tissue that are expressing AAV-mCAT at the time of improvement in function, and if mCAT is expressed in other tissues aside from the heart. My role in particular is to determine the expression levels of catalase in various tissues, which could affect cardiac function. We present evidence of improvement of diastolic function by longitudinal echocardiography, and expression of the mitochondrial-targeted catalase gene (MCAT) in various tissues, after injection of AAV expressing MCAT (AAV9-MCAT) into aged female mice. This pilot project shows that the AAV9-MCAT has the potential to be an eventual therapy for aging-related diastolic dysfunction, for which there is presently no effective therapy. Thus, AAV9-MCAT is a novel and promising method of reversing the effects of aging on cardiac health.

Writing is both emotional and intellectual task. For writing tutors, it is not rare to encounter writers asking for affirmation on their work, regardless of the quality of works and confidence level of writers. There is a bias, or expectation, that one’s role as a tutor is to provide intellectual support on the writing material. Thus, there is little literature or discussion on how tutors may provide additional types of support to the writer. Recognition of emotional support in the writing center is significant as it creates a perspective shift on the role of writing tutors and the function of writing centers. The research is designed to observe how often writers seek emotional support (e.g. demand affirmation or approval) from tutors in addition to intellectual support (e.g. grammar checks) and how current tutors engage in providing emotional support. Data for the study is drawn from 40 both undergraduate and graduate tutors who are currently working actively at Odegaard Writing and Research Center. The tutors participated in an anonymous self assessment survey online in which they were asked to identify how frequently they feel, encounter, or engage in specific behavior. The questionnaire is divided into three parts: Tutors’ emotional labor, Tutors’ identification of Writers’ demanding of emotional support, and Tutors’ accommodation of Writers’ emotional demand. This study found 72% of tutors encounter a writer’s emotional expression, 69% of tutors spend time to build a personal connection with a writer, and 67% of tutors often to always try to comfort stressed writers. The findings indicate consistent demand in emotional support from writers and emotional labor on part of tutors. This provides a foundation for further research to be conducted in exploring the roles of academic tutors beyond providing intellectual support.