The Pondaung Formation of central Myanmar consists of fluvial and alluvial sedimentary rocks deposited during the Middle Eocene, 40 million years ago. The formation has yielded fossils of some of the earliest anthropoid primates, coeval with the first primate dispersal from Asia to Africa. Previous sedimentological and paleobotanical studies have shown that the Pondaung Formation was deposited in a landscape of open-forested seasonal wetlands with isolated riparian and monsoonal deciduous forests. However, the spread of these forests and locations of primate habitats within this mosaic landscape remains unclear. This project aims to provide a more precise reconstruction of the landscape at primate-bearing fossil sites using isotopic data gathered from paleosols as proxies for vegetation and climate during its deposition. We propose to use carbon isotope data collected from soil organic matter to produce estimates of precipitation. They are combined with the carbon isotopic composition of pedogenic carbonates to give direct estimates of soil productivity and vegetation cover. Together, these data allow us to decipher the landscape at the fossil sites, providing context for the evolution and dispersal of these primates. Our preliminary results agree with previous studies of the region, showing that the landscape was forested and flooded for considerable periods of time, experiencing strong seasonality in precipitation.

The landscape of southwest Montana is dominated by topography and adjacent sedimentary basins that resulted from deformation associated with the Sevier and Laramide orogenies140-50 million years ago and ~70-40 million years ago, respectively. Stark changes in drainage and deposition from Permian to Miocene (300 to 5 million years ago) have been described from uplifted sedimentary sequences. Despite numerous studies, the precise timing of eastward propagation of the Sevier fold‐thrust belt and its impact on drainage, as well as the timing of sedimentary basin partitioning into smaller intra-basins remain unclear. For this project, I worked under the guidance of Dr. Licht and Megan Mueller to collect field samples in Montana, isolate zircon grains for analysis and synthesize the results. Here we present geochronological and petrographic data that explain the timing of changes in drainage patterns, and place constraints on the chronology of orogenic development from Permian through Miocene sedimentary rocks exposed near Dillon, southwest Montana. The techniques used in this study are zircon geochronology and sandstone petrography. Zircon geochronology determines the age of zircon minerals found in sediment and offers insights into the ages of the sediment source areas. Sandstone petrography is used to classify the mineralogy of grains in sandstones and allow us to determine potential sediment sources. Understanding the evolution of drainages and changes in sediment transportation is critical to reconstruct the complex tectonic history of this region and aid in uncovering the chronology of Sevier and Laramide deformation.

The uplift of the Cascade Range in Washington had a dramatic impact on regional ecosystems and global climate by creating continent-scale rain shadow effects, enhancing regional aridity, and providing an anchor to the North American ice-sheet during glacial ages. Despite their importance, however, the chronology of the Cascades uplift remains poorly understood, with proposed ages for the uplift ranging from Eocene (~40 million years ago) to Pliocene (~4 million years ago). Before the onset of uplift, rivers would have drained westwards across Washington State; the uplift would have disrupted these river systems and separated river drainages on both sides of the mountain range. The goal of this study is to determine when uplift began by determining when this drainage disruption occurred. To do so, we propose to compare the sedimentary provenance of geological units of various ages on both sides of the mountains. Our methods include U-Pb dating of detrital zircons and sedimentary petrography of sandstones. Sediment samples on the west side of the Cascade Mountains have previously been analyzed for these two methods on an earlier research project. We will focus here on new results from multiple samples from the east side of the Cascade Mountains, and compare them with samples from the west side to propose a time window for the onset of uplift.

Malaria devastates communities around the world, and researchers are striving to solve this enormous global health problem. Vaccine candidates could control malaria in these areas. Unfortunately, producing a single dose of these vaccines requires millions of malaria parasites from thousands of mosquitoes. Currently mosquitoes are dissected by hand, and the parasites are extracted from the dissected material with a tiny pestle. This work is time-consuming, expensive, and produces low parasite counts. With current techniques, vaccines will be difficult and expensive to produce, preventing them from protecting malaria-endemic populations. My project is to overcome the technical challenges described above by developing a system that will automatically dissect mosquitoes and extract malaria parasites. Our team has built a mosquito dissection robot and an automatic grinder. By hand, an experienced technician can dissect 150 mosquitoes per hour, but we are designing our robot to dissect over 1200 in the same time. By automating this process we improve yields and save time. In the future we will manufacture and distribute these tools to other labs. To confirm the quality of the parasites our robots extract, we are conducting extensive biological testing.

Malaria, a disease caused by Plasmodium parasites, is an enormous public health burden, especially in resource-poor areas of the world. After the female Anopheles mosquito deposits the Plasmodium sporozoite stage to the host through its saliva during blood feeding, the sporozoite quickly makes its way to the liver where it selectively invades a hepatocyte. The parasite replicates within the host cell, eventually re-entering the blood stream where it causes symptomatic infection. My project focuses on the liver stage of malaria, where complex hepatocyte signaling pathways contribute to parasite development and replication. Previously, our lab demonstrated that host signaling pathways that control lipid peroxidation are crucial to regulating liver stage infection during the first 24 hours. Inhibiting SLC7a11, a protein associated with the regulation of lipid peroxidation, led to increased peroxidated lipids within the infected cell and reduced Plasmodium liver stage parasite infection. Interestingly, lipid peroxides were localized to the infected hepatocyte, leading us to question the kinetic and spatial distribution of peroxidated lipids within the infected hepatocyte. I cultured Hepa 1-6 cells and infected them with Plasmodium yoelii sporozoites. After infection, I treated the cultures with drugs that promote or inhibit SLC7a11. Lipid peroxide levels and localization were observed by fluorescent microscopy at six hours post-infection and mean fluorescent intensity was quantified. At six hours post-infection, I observed no significant difference in lipid peroxidation when comparing infected and uninfected cells, suggesting that lipid peroxidation in infected cells occurs at some point between 6 and 24 hours. This project will allow us to gain a better understanding of how the lipid peroxidation pathway contributes to limiting Plasmodium infection within the liver and how it might be targeted by therapeutics to selectively kill parasites without harming the host.