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An Investigation Into the Natural Mineral Lick at Lick Creek

Toby Dunn

The natural mineral lick at Lick Creek in the Bitterroot National Forest was studied to determine the types and concentrations of minerals found in the licks and what the potential source for the minerals may be. Soil samples were taken from seven different “lick pits” that were formed by elk and deer, as well as three different dig sites. Samples were also collected from the two proposed sources of the minerals, Mazama and Challis volcanic ash. An experiment was performed on the soil and ash samples to determine the amount of dissolved electrolytes in the solution and how that amount may change over time. This was accomplished by adding 30 mL of sample to 120 mL of distilled water in jars. The first test was conducted 10 minutes after the samples were mixed and the second test was conducted 24 hours later. The concentration of electrolytes was measured using a Total Dissolved Solid/Electrical Conductivity meter in units of parts per million. Solutions from one mineral lick soil sample and samples of Mazama and Challis ash were sent to Energy Laboratories for further analysis of the specific mineral composition. The laboratory results indicate that there are notable quantities of calcium, magnesium, sodium, and potassium present in all three samples. The ratios of the minerals from each sample indicate that Mazama ash is the most likely source for the natural mineral lick at Lick Creek. This research brings to light how geological events of the past created an environment that provides a valuable resource to elk and deer in the present, in the form of electrolyte supplementation for proper biological functioning.

Analyzing the multipath of GPS time series to study snow properties

Ashlesha Khatiwada, University of Montana

Thousands of Global Positioning System (GPS) receivers worldwide record signals sent by satellites to infer how each receiver (and the ground they are attached to) moves over time. The motion of GPS receivers are used for many purposes, including studying tectonic deformation and changes in Earth's shape caused by surface loading. In this project, reflected wave arrivals contained within the multipath signal of GPS time series are extracted and analyzed to advance understanding of snow properties in mountainous regions of Montana/Idaho, USA. Analyzing reflected signals in GPS series has potential to reveal properties of local snowpack, such as height, water content, snow surface temperature, dielectric properties, and density. Improving our ability to monitor physical characteristics of snowpack and how they evolve over space and time is essential as properties of snow are key to understanding the slippage of one layer on another, which impacts avalanche hazard. Moreover, snowpack monitoring provides information about availability of water resources and snow hydrology. This project focuses on analyzing the ray paths and attenuation of reflected GPS signals, also using reflections to infer properties of snow. Traditionally, to study snow properties, one must manually dig a snow pit to study the snowpack and/or use expensive remote-sensing technologies (e.g. InSAR). However, digging snow pits can be dangerous due to avalanche risk as well as costly and time inefficient. Relatively low-cost GPS stations that are now widely deployed worldwide present new opportunities to study snow properties, including in developing nations with fewer financial resources. We will use GPS interferometric reflectometry (GPS-IR) software developed by Kristine Larson (CCAR) to infer snow depth data from GPS multipath. Results will be validated with nearby instruments, such as Snow Telemetry (SNOTEL) and a co-located weather station, as well as by visiting the site in person to measure snow properties manually.

Determining the Scale of the Heliosphere Using IBEX and Solar Wind Data

Joseph D. Kelly, University of Montana, Missoula

The heliosphere is a vast region of space which surrounds the solar system and is created by the magnetic field of the Sun. The region inside the termination shock is a cavity in the magnetic field of the interstellar medium present outside the solar system, and has a “nose” and “tail” caused by the flow direction of the interstellar medium with respect to the Sun. Solar wind is the continuous flow of charged particles, produced by the Sun, which emanate outwards along the Sun’s magnetic field lines. When the solar wind reaches the termination shock, solar wind ions that neutralize in interactions with other particles are no longer bound to the magnetic field and follow ballistic trajectories as Energetic Neutral Atoms (ENAs). The Interstellar Boundary Explorer (IBEX) is a satellite which measures ENAs produced in the heliosheath which are directed back towards Earth. Changes in the solar wind pressure over time are reflected in ENA production in the heliosheath. Hence, by correlating ENA fluxes in a specific region of the sky with past solar wind pressure data, the time gap between changes in the solar wind pressure and returning ENA fluxes can be determined. By then analyzing the speed of the incoming ENAs, we can determine the approximate scale of the heliosphere. We limited ourselves to looking in the “nose-ward” direction of the heliosphere in the equatorial region, where simplifying assumptions can be made about the speed of the solar wind and the interactions of the solar wind in the heliosheath. The determined distance to the termination shock with this method was roughly 125 AU.

Introducing human-like mutations in yeast iso-1-cytochrome c to decrease peroxidase activity in apoptosis

Sidney Thompson, University of Montana, Missoula

The mitochondria is an important organelle for a large assortment of metabolic processes. Cytochrome c (Cytc), a vital protein found in the mitochondria, is critical for life and death processes in eukaryotic cells. One of these functions includes shuttling electrons through the electron transport chain during cellular respiration. Cytc is also an essential signaling protein in the pathway of apoptosis, also known as programmed cell death. Yeast has similar components of this cell death pathway to higher eukaryotes such as humans, but does not contain all of the same optimized cascade processes. Additionally, peroxidase activity, an early signal in the apoptotic pathway, is much lower in human Cytc when compared to wild type yeast iso-1-Cytc. This suggests the evolution of an optimized “off” state in the peroxidase activity of human Cytc. In the least stable substructures of Cytc, which mediate peroxidase activity, three amino acid sites co-evolve between human Cytc and iso-1-Cytc. In comparison to iso-1-Cytc, human Cytc contains the substitutions S40T, V57I and N63T. These should stabilize this hydrophobic interface in human Cytc by the addition of a methyl group in each substitution when compared to iso-1-Cytc. All possible single, double and triple substitution variants from Hu Cytc were introduced into iso-1-Cytc to test the hypothesis that they would increase the stability of iso-1-Cytc, causing the peroxidase activity of iso-1-Cytc to decrease. Bacterial protein expression of the single and double mutation variants in BL21 Escherichia coli cells, followed by protein purification were performed. Further experimentation on the individual mutant proteins to test the hypothesis included measurement of peroxidase activity, the alkaline transition, and protein stability. Apoptosis is often dysregulated in cancer. Therefore, further understanding of how the peroxidase activity of Cytc is controlled can have future implications for understanding Cytc’s role in both the proliferation and treatment of cancer.

The Use of Silicone Wristbands as Passive Samplers for Measurement of Wood Smoke Analytes

Alice R. Giem, University of Montana

As the people of Montana know, wood smoke from wildfires during the summer can have a negative effect on health. Exposure to smoke produced by wildfires is a health concern worldwide. With many Montana residents working as wildland firefighters during the summer, their exposure to the many compounds from smoke with negative health effects is high and so the concern for their health is high as well. Many past studies have measured the quantities of particulate matter in the smoke as the main health concern, but exposure to volatile compounds produced remains understudied. This research focuses on improving a method of quantitative measurement of exposure to these compounds using silicone wristbands as passive samplers. This study developed a method of wristband cleaning to minimize chemical waste and ensure reuse of wristbands in the future. The study also developed a method to extract analytes of interest from the wristbands and quantify a few volatile organic compounds and polycyclic aromatic hydrocarbons with known ill health effects. The focus of this study was to ensure that the wristbands would give consistent results after multiple exposures to analytes. Wristbands were spiked with various concentrations from solutions of the analytes of interest. After allowing the spiked wristbands to equilibrate, they were extracted while considering green chemistry. This research can lead to use of silicone wristbands being used as passive samplers with wildland firefighters to quantify exposures. These data could be used to estimate exposure of firefighters to the harmful chemicals in wood smoke.

Wind Determination Using a Rigid-Body Model of Quadrotor Motion

Beau G. Goldberg, University of Montana, Missoula
Javier Gonzalez-Rocha, University of California, Riverside
Jaylene Naylor, University of Montana, Missoula
Jennifer Fowler, University of Montana, Missoula

Building on current methods for accurately determining wind velocity using quadrotor aircraft dynamics, this research helps lay the groundwork for more cost-effective access to wind data as compared to using traditional technologies such as balloon-borne radiosondes. By constructing a dynamic rigid-body model to describe the aircraft’s response to wind perturbations, we are able to determine wind speed and direction. Data collected from University of Montana’s Weather Quadcopter flights is processed using system identification algorithms resulting in excited motion models which are combined to form the rigid-body model. A differential equation describing the state of the aircraft can then be crafted. Solving this differential equation allows for convergence of the system to an estimated state containing the desired wind values. Model tuning is then performed to reduce the uncertainty in wind speed and direction. Preliminary results indicate agreement of 90% between the model and reference data. The ease with which the rigid-body model can be identified for different quadrotor configurations makes it a highly accessible and scalable method for wind determination.