Neutrinos and antineutrinos are elementary particles with no electric charge and very small masses. From neutrino oscillation experiments we know their mass differences but not their absolute scale. Additionally, it is unknown whether neutrinos are their own antiparticles. These are two of several significant questions in neutrino physics and are important for furthering our fundamental understanding of the universe as we extend the Standard Model of particle physics. These questions can be probed by a search for the rare hypothetical radioactive decay known as neutrinoless double beta decay. The Majorana Demonstrator experiment will look for neutrinoless double beta decay in ⁷⁶Ge. Currently, the Majorana Demonstrator is in the development stage, and involves the collaboration of several universities and national laboratories. My research characterizes electrical crosstalk between nearby readout channels for this experiment. As neutrinoless double beta decay is hypothesized to such a rare process, a thorough understanding of the electrical crosstalk is necessary to adequately interpret the measured signals.

Many examples of control systems are found in modern-day industrial applications, ranging from the Segway to cruise control in an automobile. The self-stabilizing inverted pendulum serves as an archetypal problem by which the robustness of such control systems, which use feedback to control themselves, is measured. In this project, I analyze several simple control systems involving the inverted pendulum, and attempt to find their stability solution. I have also built a computer simulation in Mathematica, a computational software package, which demonstrates fundamental concepts in control theory, as well as the difficulty of manual control and the usefulness of feedback in self-stabilizing systems. This simulation provides a useful learning tool to users who otherwise have little experience with the theory of control. Finally, I investigate theoretical problems related to the so-called radius of stability, which is a number that tells us how far we may deviate from equilibrium before the control system fails. I hypothesize that as further variables are introduced into a control model, the radius of stability will decrease accordingly. Since control systems are widely used in modern day society, it is important that we understand the stability of such systems, thereby maximizing the safety and effectiveness of their applications.

Phytoliths, microscopic plant silica bodies, inform us about the types of plants that remain in the fossil record, allowing for reconstruction of past flora, climate, and ecosystems. The existing method for reconstructing vegetative structure and habitat type (open vs. closed) using phytoliths depends on the presence of presumed open-habitat grass types. This method may not be able to reliably reconstruct vegetation type when open-habitat grass phytoliths are absent, and depends on the assumption that open-habitat grasses have always been restricted to open environments. Therefore, a taxon-free, morphological approach may be more informative for inferring habitat openness using fossil phytolith assemblages. This study looks at the effects of light variation on epidermal cell shapes in modern grasses as a first step in creating a proxy for determining habitat type from the fossil record. Based on patterns observed in dicotyledonous plants, we hypothesize that epidermal grass cells will be more undulated when grown in reduced lighting condition. To test this, five species of grasses were grown in varying light treatments (20%, 60%, 100% (control), and 120% relative to the control). We took morphometric measurements of long and short cell types from epidermal peels and calculated their degree of undulation (UI). Results show three species where long cells had higher UI in deep shade (20% light) than in enhanced light (120% light), though the relationship is non-linear. With short cells only one species displayed a continuous increase in UI as light levels decreased. Thus, data from long cells show the greatest promise for use in the fossil record. To further test this method for paleoecological work, the UI of epidermal cells in soil phytolith assemblages from known modern habitat types will also need to be examined to see whether this UI and light correlation persists under natural growth conditions.

The syntax of common practice tonality creates the potential for expansive musical works, with almost guaranteed gratification for the listener through a harmonic interplay between tension and resolution. The evolution of common practice tonality from the older system of modes spans the sixteenth and seventeenth centuries. With a focus on the seventeenth century, this study endeavors to clarify how, when, and, to some extent, why the monumental shift between modality and tonality occurred. A discussion of crucial differences between the two systems of musical organization—mainly the melodic basis of the modes versus the harmonic basis of the tonal major and minor scales—serves as the starting point for analysis. Following is an examination of figured bass practice as well as music theorists’ increasing acknowledgement of a tonal system in order to shed light on how contemporary tonal developments were understood. Finally, an analysis of music highlights sixteenth-century tonal seeds and shows how composers from Claudio Monteverdi (1567-1643) to Arcangelo Corelli (1653-1713) developed discreet tonal regions and linked them through directed harmonic motion to establish tonal hierarchies locally and globally. Ideally, this project does justice both to the breadth and specificity required of this expansive topic and serves either as an extended study for a music survey course or as a springboard for further focused research.

We consider a mathematical optimization problem that can be used to describe various physical situations that arise in physics and EE applications. In its general form, we study the following physical setting: There is some substance emanating from a source, which propagates through an inhomogeneous medium and reaches a drain. As a motivating application, we imagine a spark of fire igniting and spreading through a forest landscape. Alternately, light may be emitted from a point source and travel in a space with lenses of varying indices of refraction. In each case, we would like to influence the substance’s movement by optimally altering the medium in which it propagates. In the case of a forest fire, this corresponds to locating optimal places on the forest landscape to place water, in order to minimize the first arrival time of the fire at a specific location. To solve this convex optimization problem, we perform two tasks. In its general form, our first task relates to finding the shortest distance between a pair of points on a curved space, which is the solution to the Eikonal partial differential equation. Secondly, we take the derivative of the Eikonal solution with respect to a medium parameter. Due to the nature of our problem, these operations cannot be performed analytically. The results are approximated with the Subgradient Marching Algorithm. The unique element of this project has to do with the way we preform the algorithm. Once the shortest-path-length solution and its subgradient are known, we recognize a strategic location on the forest landscape to place a fire deterrent. In this work, we study and implement the overall optimization algorithm, and demonstrate an application to the forest fire problem.

 Extraterrestrial regolith can be utilized for a variety of in-situ resource utilization applications including the production of oxygen and slurry materials. These capabilities are crucial for the success of long-term missions to both the Moon and Mars. However, the value of the regolith often depends on extracting a specific particle size. Therefore, our objective is to develop a regolith sifting system for integration into extraterrestrial surface systems. Furthermore, this system will be designed to operate independent of gravitational forces in order to offer flexibility by maintaining the same degree of reliability and efficiency in terrestrial, lunar, martian, asteroidal, and orbital environments. To accomplish this task, a centrifuge design was adopted. A container fitted with two sets of sifting screens is rapidly spun so that the centripetal forces cause the particles to pass through the screens. At high speeds the effects of gravity and particle cohesion become negligible. The design was carried through several stages of development where parameters such as geometry, induced agitation, sample size, rotation speed, and test duration were optimized to give accurate sorting results with minimal energy input. Data collected from ground testing will be compared to data collected on NASA’s low-gravity aircraft in June. The low-gravity testing introduces more challenges to the design, such as automated gates that keep the particles from self-sorting in between low-gravity flight parabolas, and integration into a air-tight glove-box for safety. For future research, techniques for autonomous and continuous operation will be crucial for adoption into extraterrestrial surface systems.

The reduction of CO₂ has become a global priority as the concerns of climate change and the adverse effects of atmospheric carbon dioxide on the environment continue to rise. One method of reducing CO₂ emissions is through conversion and utilization as a chemical feedstock. CO₂ is cheap, nontoxic, and can be recycled to produce valuable new products, making it an attractive feedstock. The increasing importance of CO₂ utilization processes requires a better understanding of the underlying mechanisms of its conversion. The industrial conversion of CO₂ is typically achieved using a heterogeneous catalyst, usually consisting of small transition metal particles supported on a high surface area metal oxide. Our project focuses on elucidating the mechanism of the reverse water-gas shift (RWGS) reaction on platinum, an extensively studied catalyst with a highly active surface. Our goals are (1) to quantitatively measure the RWGS rate under conditions of low H coverage and (2) to compare the measured rate to the rate of CO₂ dissociation (the rate-limiting step according to the surface redox mechanism) and to the theoretical rate calculated using a micro-kinetic model based on the associative mechanism. The information we gather from the investigation will clarify whether the RWGS reaction proceeds on platinum via the surface redox mechanism or the associative mechanism.

The magnitude of trade in food within an increasingly globalized world has contributed to a situation where the populations that produce food often do not receive the ultimate benefits of their labor. For example, food production in one place might primarily support the production of manufactured goods and services that benefit people in distant places. The degree to which agriculture in a certain region supports economic activities abroad varies enormously across the globe. This study aims to understand how food production supports flows within the global economic system and contributes to unequal relationships between different regions of the world. To do this, global economic flows are modeled by entering production and consumption data into an interregional Social Accounting Model and analyzed within a geographic information system. From this, we have been able to identify the most important globalized croplands and categorize regions by the “function” they serve in global webs of production and consumption similar to an ecological trophic level analysis.  These results suggest that uneven flows of embodied food production between regions may be related to global patterns of poverty and health, as well as to the prospects for a more sustainable human ecosystem.

Currently, freight models at the state level use a four-step modeling approach, which generates trips based on origins, destinations, and land use. In the personal travel sector, models have started taking into consideration entire tours based on household demographics. Freight modeling uses this same approach despite situational differences. In an effort to improve freight modeling, this research aims to identify characteristics of freight carrier companies that determine distinct freight movements. A survey of licensed motor carriers was designed and conducted in Washington State and Oregon State. The identical surveys conducted in both states consisted of 33 questions. Respondents were asked questions regarding their vehicle fleet, locations served, times traveled, types of deliveries, and commodities. A total of 614 complete responses were gathered. An analysis of the data, using statistical software R and Excel, aims to reveal clusters of company types that can be distinguished by determining characteristics such as company size, commodity, and role in a supply chain. By identifying unique patterns among the dependent variable such as travel distance, travel times, and delivery style, the results can then be integrated into state models to more accurately predict freight vehicle routes.

Displays in general are designed objects meant for communication and notification. The display design has become even more important as the necessity of such information communication increases, such as displays used in control rooms and in manufacturing systems. The ineffectiveness of such displays can lead the operator to make costly errors. While there have been many advancements in the physical configuration of displays, the use of color in designing such objects has not been studied excessively. Moreover, with regards to the selection of colors and allocating them on the display, no general solution exists.This research will place an emphasis on finding a methodology for the use and allocation of colors in display design and will be an innovative contribution to the field of display design and, more generally, human factors engineering. Our research question is divided into two parts: determining if incorporating colors into displays is effective in reducing recognition time and increasing accuracy of signals, and, investigating how colors should be allocated, as well as successful methods of color-coding. Our research hypothesis is that use of colors will yield higher accuracy rate and lower detection time; however, we will weight accuracy more strongly than speed. In that matter, we believe that using colors as an additional tag of data will improve both priorities. The form of this study would be similar to a simulation game. We have designed a display using a simulation program called NetLogo. The display has multiple elements. It is programed in a way that would automatically simulate a thermodynamic reaction when activated. Human subjects will be used to detect the signals in a timely manner and respond to prompts appearing on the screen. The simulation game will record the time and accuracy of the responses. These data will be analyzed and conclusions will be drawn.

This paper applies the theory of real options to study the dynamics of input substitution in the uranium enrichment industry. Enrichment is a process whereby natural uranium is separated into a stream rich in the fissile isotope U²³⁵, which is used as nuclear fuel, and another “tails” stream with a low U²³⁵ content, or a low “tails assay.” As more separative work energy is used in the process relative to a given amount of natural uranium feed, the resulting tails assay falls and the amount of fuel produced rises. A well-known formula asserts that a cost-minimizing enricher will choose a given level of inputs based only on the relative price of enrichment and uranium, but I show that the standard formula ignores the potential value of holding the leftover tails for further enrichment if that relative price of uranium rises. The theory of real options, a subfield of finance, shows that this decades-old formula is incorrect. I quantify the value of the option to enrich if the relative price of uranium should rise. I then use a numerical method to calculate a new optimal ratio of separative work to uranium that takes into account the price volatility of the relative price of the inputs, and I find that the option-adjusted optimal input ratio uses significantly less separative work, leaving richer tails, than the standard formula under realistic assumptions of price ratio volatility.

Cooperative interactions are observed at all levels of biological organization. Cooperation facilitates major transitions in evolution such as from unicellularity to multicellularity. How a cooperative system evolves from its incipient state is unknown. I have used a synthetic cooperative system termed CoSMO (Cooperation that is Synthetic and Mutually Obligatory) as a model for incipient cooperation. CoSMO is an engineered yeast system consisting of two non-mating strains, differentially labeled with fluorescence. It relies on direct exchange of distinct metabolites between the two cooperators. Evolved CoSMO cocultures exhibit an improvement in viability, defined as an increased ability to survive reductions in population density. I have determined that this viability improvement is heritable, by measuring the viability of reconstituted evolved CoSMO pregrown in rich media which allow cells to grow in the absence of cooperation. Furthermore, by mixing an evolved strain with its ancestral partner, I determined that a single evolved cooperator was responsible for community-level viability improvement. I am characterizing phenotypic changes in evolved cooperators that contribute to increased viability. The phenotypic changes can potentially be categorized as either “self-helping”, such as through increased starvation tolerance and higher affinity for metabolites, or “partner-helping”, such as through increased metabolite release. In all cases, I will identify the molecular basis for these adaptations through genome-wide re-sequencing. Furthermore, genomic analysis on entire evolved CoSMO cocultures will be performed to reveal the diversity and frequency of relevant mutations in the population over time. Lastly, I will perform similar analyses on replicate populations. If similar adaptive changes that result in improvement in system viability are observed, a deterministic process to improve viability is implied. Otherwise, diverse mechanisms can achieve improved fitness. In both cases, we will gain insights into how cooperative systems evolve from inception.

Intramuscular injection of Botulinum toxin(BTX) is a common approach to reduce muscular mass for cosmetic effect and to relieve symptoms of muscle spasm and pain through the mechanism of paralysing nerve-muscle junctions of the target muscle. However, the consequences of this neuromuscular blockage in masticatory muscles have not been evaluated. The goal of my research is to investigate the short- and long-term effect of the use of BTX on masseter muscles by evaluating evoked electromyography (EMG) in a rabbit model. Of 22 rabbits, 10 were injected once with 10 units of BTX in one masseter and examined 4 and 12 weeks after the injection (5 each); 7 were injected 3 times at 0, 12 and 24 weeks and examined 36 weeks after the first injection; and 5 were intact animals. My work is to assess masseter EMG signals evoked by electric stimulations of ipsilateral masseteric nerve, and to evaluate the regional effects of neuromuscular blockage based on a wire-electrode array placed on the masseter across various time points with single or multiple BTX injections. I use both time- and frequency-domain methods to analyze these signals and to compare their amplitude, timing, and frequency between injected and non-injected sides, single and multiple injections, and injected and intact animals. The study design also allows me to elucidate the recovery effects over time. The preliminary results indicate that a single BTX application significantly affected the responses of injected muscles to nerve stimulations, presented as an ~80% reduction in EMG amplitude at 4 weeks, and ~65% reduction at 12 weeks. At 36 weeks, the sides differed little if at all, suggesting partial recovery had occurred even though multiple injections were applied. My work is continuing to find out whether the masseter’s neural transduction (timing) and firing (frequency) are affected by BTX application.

Complexity of today’s financial markets and its services demand high degree of financial knowledge than ever before from individuals in order to make prudent financial decision. Early studies have shown that financial illiteracy is widespread and that those who are financially illiterate display both poor borrowing and saving behavior. Using household data from HRS (Health and Retirement Study), I test the hypothesis that financial literacy is a strong determinant of accumulation of wealth. That is, those who possess greater financial knowledge accumulate more wealth than those who have low or no financial knowledge. Moreover, I extend the analysis in an attempt to answer what drives individuals to acquire financial knowledge. My first hypothesis is that poor living circumstances at young age make individuals become more aware of the importance of finance: hence, it is a driver of financial knowledge. My second hypothesis is that past experiences (loss of portfolio value from recession and poor health) play a role. Data on several components of wealth, financial literacy, and past information were compiled and will be used to run regression to answer underlying questions. Finally, I explain what it means to be financially literate. The purpose of this analysis is to stress the importance of being financially literate and that finance class should be part of school’s core curriculum. This will better prepare our descendents for far more complex financial markets that lie ahead.

The development of satellite technology has enabled scientists to develop a greater understanding of the movement patterns of various animals. Specifically, the movement of polar bears in Greenland is of ecological interest due to sea ice loss in the Arctic. Researchers tag polar bears with satellite collars and collect various samples and measurements such as age, sex, body mass, and body condition. Bears are tracked using polar-orbiting satellites and the data are collected and transmitted by Advanced Research and Global Observation Satellite (ARGOS). The large volumes of data are reported in coded text files that are difficult to analyze and contain error. I developed a program to extract data from ARGOS written using the statistical programming language R. This program allows for covariates on individual bears to be merged with satellite location data. I created two error checked databases (filtered and unfiltered) on movement of polar bears in Greenland. This program will facilitate data analysis of the movement patterns of polar bears.

Despite the numerous studies of the bacteria E. Coli, the basic motion of macromolecules confined to the cellular cytoplasm, such as mRNA, remains uncharacterized. I employ a technique called fluorescent correlation microscopy, which consists of binding synthesized mRNA with fluorescent proteins, imaging the cell throughout its lifetime, and analyzing the images using statistical autocorrelation. This technique allows me to determine the diffusion constant (D) as a function of cellular location while bypassing the error caused by higher order analysis. We predict that D is primarily dependent on the molecular crowding at its position, and there exists a tendency for mRNA to gather in the less crowded spaces in the cell, e.g. at the poles.

Model membranes are important tools for investigating physical properties of lipid bilayers. Unfortunately, current techniques for producing giant unilamellar vesicles (GUVs) with biologically and physically relevant properties (namely: inclusion of charged lipids, encapsulation of high salt buffer, and compositional asymmetry between the inner and outer leaflets) are difficult, unreliable, and/or low throughput. We examine a method called cDICE, developed by Abkarian et al., that has the potential to address all of these issues. Our results here for charged lipids in high salt buffers are promising, whereas asymmetry has proven difficult to measure.

Manipulation of inflation reports is a rarely known tool that policymakers use to generate temporary growth and more revenue than they would with an explicit monetary expansion. The Argentine government has intervened in its Statistic Department since early 2007. Several private estimates and scholarly studies have shown that the real inflation rate is in fact between two or three times the officially reported inflation rate. However, the current studies have only produced price indexes from December 2007 to present, which does not include the crucial period when the manipulation in inflation reports was first implemented. In this project, I will create an alternative price index from January 2006 to January 2009, which will bridge the gap from when the Argentine Statistic Department was still respectable to when its was widely known of misreporting inflation rate. I will assess the validity of my index by comparison with the published studies for 2008, the year that already has an alternative price index. From my index, I will be able to determine an accurate date when the misreporting inflation date started, and by also having the data for that crucial period, I will contribute to the study on the cost of misreporting inflation. I will be using the monthly average prices of 60 representative goods to construct an alternative price index comparable to the officially reported one. This valuable dataset includes the publications of the Consumer Action League and receipt records in a supermarket’s archives. Both database are rare to find because the Argentine government started to censor and punish domestic independent studies on inflation with heavy fines beginning on 2011. The preliminary results show that the manipulation of reported inflation started in February 2007.