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Educational Disparities Among Racial And Ethnic Minority Youth In The United States, Lauren Bushnell May 2021

Educational Disparities Among Racial And Ethnic Minority Youth In The United States, Lauren Bushnell

Ballard Brief

While the gap in high school completion has narrowed over time. the percentage of Black and Hispanic high school graduates is still significantly less than that of their White counterparts. Throughout the nation, minority students experience disparities in their educational experience that directly impact their long-term learning and success. The most significant contributors to educational disparities amongst the nation's racial and ethnic minorities include poverty, segregation and racial school districting, inadequate language resources for English language learners. bullying. and lack of access to health resources. The consequences of educational disparities among these minorities include continued poverty, decreased college enrollment and …

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Inadequate Resettlement Of Refugees In The Southern European Union, Jenna Vasquez May 2021

Inadequate Resettlement Of Refugees In The Southern European Union, Jenna Vasquez

Ballard Brief

The European Union (EU) and specifically the countries in southern Europe have experienced an unprecedented number of refugees entering its countries since the Syrian Civil War began in 2011. The resettlement of these refugees has been inadequate due to a number of factors, and there are many bureaucratic obstacles to refugees applying for asylum in an EU country. Additionally, countries simply lack space, resources, and legal staff to handle the influx of newcomers. These factors lead to a variety of negative consequences for the refugees and the host countries, including violence among refugees and law enforcement and financial insecurities and …

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Digital Signal Processing Algorithms Implemented On Graphics Processing Units And Software Development For Phased Array Receiver Systems, Mark William Ruzindana Apr 2021

Digital Signal Processing Algorithms Implemented On Graphics Processing Units And Software Development For Phased Array Receiver Systems, Mark William Ruzindana

Theses and Dissertations

Phased array receivers are a set of antenna elements that are capable of forming multiple simultaneous beams over a field of view. In radio astronomy, the study of deep space radio sources, a phased array feed (PAF) is placed at the focus of a large dish telescope that spatially samples the focal plane. PAFs provide an increase in the field of view as compared to the traditional single pixel horn feed, thereby increasing survey speed while maintaining low sensitivity. Phased arrays are also capable of radio frequency interference (RFI) mitigation which is useful in both radio astronomy and wireless communications …

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Trajectory Generation And Tracking Control For Winged Electric Vertical Takeoff And Landing Aircraft, Jacob B. Willis Apr 2021

Trajectory Generation And Tracking Control For Winged Electric Vertical Takeoff And Landing Aircraft, Jacob B. Willis

Theses and Dissertations

The development of high-energy-density batteries, advanced sensor technologies, and advanced control algorithms for multirotor electric vertical takeoff and landing (eVTOL) unmanned aerial vehicles (UAVs) has led to interest in using these vehicles for a variety of applications including surveillance, package delivery, and even human transportation. In each of these cases, the ideal vehicle is one that can maneuver in congested spaces, but is efficient for traveling long distances. The combination of wings and vectored thrust make winged eVTOLs the obvious choice. However, these aircraft experience a much wider range of flight conditions that makes them challenging to model and control. …

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The Whole Is Greater Than Its Parts: Ensembling Improves Protein Contact Prediction, Wendy M. Billings, Connor J. Morris, Dennis Della Corte Apr 2021

The Whole Is Greater Than Its Parts: Ensembling Improves Protein Contact Prediction, Wendy M. Billings, Connor J. Morris, Dennis Della Corte

Faculty Publications

The prediction of amino acid contacts from protein sequence is an important problem, as protein contacts are a vital step towards the prediction of folded protein structures. We propose that a powerful concept from deep learning, called ensembling, can increase the accuracy of protein contact predictions by combining the outputs of different neural network models. We show that ensembling the predictions made by different groups at the recent Critical Assessment of Protein Structure Prediction (CASP13) outperforms all individual groups. Further, we show that contacts derived from the distance predictions of three additional deep neural networks—AlphaFold, trRosetta, and ProSPr—can be substantially …

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"Al This Loude Fare:" The Echo Of Renown In Chaucer's The House Of Fame, Madeline Nicole Anderson Apr 2021

"Al This Loude Fare:" The Echo Of Renown In Chaucer's The House Of Fame, Madeline Nicole Anderson

Theses and Dissertations

This paper approaches The House of Fame through the emerging lens of sound studies and discusses how Chaucer used the developing sonic theories of his day and other literary works as a catalyst for his discussion of fame in his dream vision. Chaucer's poem shows the fragile and uncontrollable characteristics of lasting fame by comparing it to the Boethian metaphor of sound functioning similarly to rippling water. The construction of The House of Fame ultimately becomes an example of this medieval sonic theory as it engages with, incorporates, and echoes themes and ideas from other texts. In exploring the process …

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Combined Trajectory, Propulsion And Battery Mass Optimization For Solar-Regenerative High-Altitude Long-Endurance Aircraft, Nathaniel Spencer Gates Apr 2021

Combined Trajectory, Propulsion And Battery Mass Optimization For Solar-Regenerative High-Altitude Long-Endurance Aircraft, Nathaniel Spencer Gates

Theses and Dissertations

This thesis presents the work of two significant projects. In the first project, a suite of benchmark problems for grid energy management are presented which demonstrate several issues characteristic to the dynamic optimization of these systems. These benchmark problems include load following, cogeneration, tri-generation, and energy storage, and each one assumes perfect foresight of the entire time horizon. The Gekko Python package for dynamic optimization is introduced and two different solution methods are discussed and applied to solving these benchmarks. The simultaneous solve mode out-performs the sequential solve mode in each benchmark problem across a wide range of time horizons …

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A Hybrid Method For Auralizing Vibroacoustic Systems And Evaluating Audio Fidelity/Sound Quality Using Machine Learning, Andrew Jared Miller Apr 2021

A Hybrid Method For Auralizing Vibroacoustic Systems And Evaluating Audio Fidelity/Sound Quality Using Machine Learning, Andrew Jared Miller

Theses and Dissertations

Two separate methods are presented to aid in the creation and evaluation of acoustic simulations. The first is a hybrid method that allows separate low and high-frequency acoustic responses to be combined into a single broadband response suitable for auralization. The process consists of four steps: 1) creating separate low-frequency and high-frequency responses of the system of interest, 2) interpolating between the two responses to get a single broadband magnitude response, 3) adding amplitude modulation to the high-frequency portion of the response, and 4) calculating approximate phase information. An experimental setup is used to validate the hybrid method. Listening tests …

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A Self-Study Of The Shifts In Teacher Educator Knowledge Resulting From The Move From In-Person To Online Instruction, Celina Dulude Lay Apr 2021

A Self-Study Of The Shifts In Teacher Educator Knowledge Resulting From The Move From In-Person To Online Instruction, Celina Dulude Lay

Theses and Dissertations

Given the competing contexts of teacher education, it is important to uncover what teacher educator knowledge concerning curriculum design and development emerges in design, implementation, and instruction during the transition from in-person to online contexts. Yet, there is little research that uncovers teacher educator knowledge in curriculum making generally, and more specifically, how this knowledge is carried forward or changed as teacher educators create and enact online teaching. Because transitions are an important time to uncover tacit and embodied understanding, in this self-study of teacher education practice (S-STEP), I examined my own teacher educator knowledge during planning, teaching, and reflecting …

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The Mechanism Of Ptov1 Regulation By 14-3-3, Huwei1 And Sgk2, Pramoda Sahan Kumari Aththota Gamage Apr 2021

The Mechanism Of Ptov1 Regulation By 14-3-3, Huwei1 And Sgk2, Pramoda Sahan Kumari Aththota Gamage

Theses and Dissertations

Prostate tumor overexpressed 1 (PTOV1) is highly expressed in several forms of cancer. High expression of PTOV1 is associated with tumor aggressiveness in several tumor types, including ovarian and breast cancer. Currently, PTOV1 is known to act both as a translational and transcriptional regulator aiding in the expression of prosurvival genes. Although PTOV1 is known to pass in and out of the nucleus in a cell cycle-dependent manner, the regulation of PTOV1 activity is not well understood and here we identify 14-3-3 as a PTOV1 interactor and show that high levels of 14-3-3 expression, like PTOV1, correlate with prostate cancer …

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You Do Math Like A Girl: How Women Reason Mathematically Outside Of Formal And School Mathematics Contexts, Katelyn C. Pyfer Apr 2021

You Do Math Like A Girl: How Women Reason Mathematically Outside Of Formal And School Mathematics Contexts, Katelyn C. Pyfer

Theses and Dissertations

Females continue to have negative dispositions towards mathematics even though the performance gap between females and males has all but disappeared. While there are many hypotheses for why these negative dispositions exist among females towards mathematics, this paper explores the possibility that the field of mathematics could favor more masculine ways of reasoning at the exclusion of valid, non-masculine mathematical thought. To research this idea, the day-to-day, non-formal, non-school mathematical activities of two women were identified and analyzed. The analysis uncovered complex mathematical processes among both women that were fundamentally different from the mathematical processes common in the mathematics field. …

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Fpga-Accelerated Digital Signal Processing For Uav Traffic Control Radar, Kacen Paul Moody Apr 2021

Fpga-Accelerated Digital Signal Processing For Uav Traffic Control Radar, Kacen Paul Moody

Theses and Dissertations

As an extension of previous work done by Luke Newmeyer in his master's thesis \cite{newmeyer2018efficient}, this report presents an improved signal processing chain for efficient, real-time processing of radar data for small-scale UAV traffic control systems. The HDL design described is for a 16-channel, 2-dimensional phased array feed processing chain and includes mean subtraction, windowing, FIR filtering, decimation, spectral estimation via FFT, cross-correlation, and averaging, as well as a significant amount of control and configuration logic. The design runs near the the max allowable memory bus frequency at 300MHz, and using AXI DMA engines can achieve throughput of 38.3 Gb/s …

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Dynamics Of Systems Driven By An External Force, Xue Liu Apr 2021

Dynamics Of Systems Driven By An External Force, Xue Liu

Theses and Dissertations

In this dissertation, we study the complicated dynamics of two classes of systems: Anosov systems driven by an external force and partially hyperbolic systems driven by an external force. For smooth Anosov systems driven by an external force, we first study the random specification property, which is on the approximation of an N−spaced arbitrary long finite random orbit segments within given precision by a random periodic point. We prove that if such system is topological mixing on fibers, then it has the random specification property. Furthermore, we prove that the homeomorphism induced by such a system on the space of …

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Computing The Rank Of Braids, Justin Meiners Apr 2021

Computing The Rank Of Braids, Justin Meiners

Theses and Dissertations

We describe a method for computing rank (and determining quasipositivity) in the free group using dynamic programming. The algorithm is adapted to computing upper bounds on the rank for braids. We test our method on a table of knots by identifying quasipositive knots and calculating the ribbon genus. We consider the possibility that rank is not theoretically computable and prove some partial results that would classify its computational complexity. We then present a method for effectively brute force searching band presentations of small rank and conjugate length.

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The Relationship Between The Use Of Curriculum Materials And Inquiry-Based Pedagogy, Laura Jo Elzinga Apr 2021

The Relationship Between The Use Of Curriculum Materials And Inquiry-Based Pedagogy, Laura Jo Elzinga

Theses and Dissertations

Little change has resulted from decades of attempts at reforming the teaching of mathematics (Davis et al., 1990). This study involved approximately 43 teachers who had completed an inquiry-based professional development program prior to being provided with a new mathematics curriculum designed to support inquiry-based teaching. It analyzed the relationships between their implementation of the inquiry-based teaching and their use of the curriculum materials. A series of bivariate correlations were run to investigate the relationships between the professional development and aspects related to the implementation of the new curriculum. The factors being so inter-related, it was hypothesized that relationships would …

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Deploying And Analyzing Air Quality Sensors In Mongolian Gers, Lehi Sttenio Alcantara Apr 2021

Deploying And Analyzing Air Quality Sensors In Mongolian Gers, Lehi Sttenio Alcantara

Theses and Dissertations

The purpose of this research is to develop best practices for deploying air quality sensors in a remote location such as Mongolia. I discussed the architecture and design constraints when collecting remote air quality sensors data, the challenges that emerge while implementing a sensor-based network in a remote location such as Mongolia. The tradeoffs of using different architectures are described. I observed the usage of electrical heaters in modified gers in remote locations and conclude how effective they are in reducing PM2.5 levels by analyzing air quality data and go through the process of cleaning up the data and removing …

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Going For Gold: Point Of Care Bio-Diagnostics And Gold Nanoparticles Treating Disease, Trevor M. Godfrey Apr 2021

Going For Gold: Point Of Care Bio-Diagnostics And Gold Nanoparticles Treating Disease, Trevor M. Godfrey

Theses and Dissertations

Correct diagnosis of disease is essential in the effort to save and improve lives. Point of care (POC) diagnostics are in-vitro tests that assist in patient diagnosis and can be used at the location of patient care. POC diagnostics are easy to use and provide near-instant readouts allowing medical providers and patients to make rapid decisions about treatment. Increased access to POC testing is especially beneficial to low-income and low resource areas that cannot afford expensive lab testing. The World Health Organization (WHO) has outlined at least 113 diseases for which POC diagnostics are needed. Because of this, developing effective, …

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Improving Artistic Workflows For Fluid Simulation Through Adaptive And Editable Fluid Simulation Techniques, Sean A. Flynn Apr 2021

Improving Artistic Workflows For Fluid Simulation Through Adaptive And Editable Fluid Simulation Techniques, Sean A. Flynn

Theses and Dissertations

As the fidelity of computer generated imagery has increased, the need to digitally create convincing natural phenomena like fluids has become fundamental to the entertainment production industry. Because fluids are complex, the underlying physics must be computationally simulated. However, because a strictly physics-based approach is both computationally expensive and difficult to control, it does not lend itself well to the way artists and directors like to work. Directors require control to achieve their specific artistic vision. Furthermore, artistic workflows rely on quick iteration and the ability to apply changes late in the production process. In this dissertation we present novel …

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The Dns Bake Sale: Advertising Dns Cookie Support For Ddos Protection, Jacob Davis Apr 2021

The Dns Bake Sale: Advertising Dns Cookie Support For Ddos Protection, Jacob Davis

Theses and Dissertations

The Domain Name System (DNS) has been frequently abused for Distributed Denial of Service (DDoS) attacks and cache poisoning because it relies on the User Datagram Protocol (UDP). Since UDP is connection-less, it is trivial for an attacker to spoof the source of a DNS query or response. DNS Cookies, a protocol standardized in 2016, add pseudo-random values to DNS packets to provide identity management and prevent spoofing attacks. This work finds that 30% of popular authoritative servers and open recursive resolvers fully support cookies and that 10% of recursive clients send cookies. Despite this, DNS cookie use is rarely …

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Multilattice Tilings And Coverings, Joshua Randall Linnell Apr 2021

Multilattice Tilings And Coverings, Joshua Randall Linnell

Theses and Dissertations

Let L be a discrete subgroup of \mathbb{R}^n under addition. Let D be a finite set of points including the origin. These two sets will define a multilattice of \mathbb{R}^n. We explore how to generate a periodic covering of the space \mathbb{R}^n based on L and $D$. Additionally, we explore the problem of covering when we restrict ourselves to covering \mathbb{R}^n using only dilations of the right regular simplex in our covering. We show that using a set D= {0,d} to define our multilattice the minimum covering density is 5-\sqrt{13}. Furthermore, we show that when we allow for an arbitrary …

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A Psychometric Analysis Of The Precalculus Concept Assessment, Brian Lindley Jones Apr 2021

A Psychometric Analysis Of The Precalculus Concept Assessment, Brian Lindley Jones

Theses and Dissertations

The purpose of this study was to examine the psychometric properties of the Precalculus Concept Assessment (PCA), a 25-item multiple-choice instrument designed to assess student reasoning abilities and understanding of foundational calculus concepts (Carlson et al., 2010). When this study was conducted, the extant research on the PCA and the PCA Taxonomy lacked in-depth investigations of the instruments' psychometric properties. Most notably was the lack of studies into the validity of the internal structure of PCA response data implied by the PCA Taxonomy. This study specifically investigated the psychometric properties of the three reasoning constructs found in the PCA taxonomy, …

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Test-Enhanced Learning In Post-Secondary Biology Courses: The Effect Of Cues And Incentives On High-Level Learning, Bryn Ellen St. Clair Apr 2021

Test-Enhanced Learning In Post-Secondary Biology Courses: The Effect Of Cues And Incentives On High-Level Learning, Bryn Ellen St. Clair

Theses and Dissertations

Cognitive scientists and psychology researchers have given growing attention to evidence of the testing effect, that is, the improvement of students' recall through memory-retrieval practice in the form of quizzes and exams. While laboratory experiments consistently show dramatic positive effects on learning through the testing effect, discipline-specific education researchers have sought to generalize these findings in real, instead of simulated classrooms. The objective of this dissertation was threefold: (1) To survey the current literature on the testing-effect as it applies to learning biology at the post-secondary level. In this review, I consider how further research on the testing effect may …

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Coal Pyrolysis Models For Use In Massively Parallel Oxyfuel-Fired Boiler Simulations, Andrew Perry Richards Mar 2021

Coal Pyrolysis Models For Use In Massively Parallel Oxyfuel-Fired Boiler Simulations, Andrew Perry Richards

Theses and Dissertations

Accurately modeling key aspects of coal combustion allows for the virtual testing and application of new technologies and processes without the need for investments in lab- and pilot-scale facilities, since such facilities may only be used for a few small tests. However, modeling of subprocesses must not only be accurate but computationally efficient. Modeling of coal devolatilization reactions and processes are one of the important parts of large-scale simulations of coal combustion systems. The work presented here details efforts to improve the modeling of coal devolatilization processes in massively-parallel simulations of coal combustors, including: (1) devolatilization rate/yield models, (2) modeling …

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Fourier Decompositions Of Graphs With Symmetries And Equitable Partitions, Darren Scott Lund Mar 2021

Fourier Decompositions Of Graphs With Symmetries And Equitable Partitions, Darren Scott Lund

Theses and Dissertations

We show that equitable partitions, which are generalizations of graph symmetries, and Fourier transforms are fundamentally related. For a partition of a graph's vertices we define a Fourier similarity transform of the graph's adjacency matrix built from the matrices used to carryout discrete Fourier transformations. We show that the matrix (graph) decomposes into a number of smaller matrices (graphs) under this transformation if and only if the partition is an equitable partition. To extend this result to directed graphs we define two new types of equitable partitions, equitable receiving and equitable transmitting partitions, and show that if a partition of …

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Light And Truth: Measuring Unseen Harm In Individuals And Communities, Hannah Pfost Mar 2021

Light And Truth: Measuring Unseen Harm In Individuals And Communities, Hannah Pfost

Undergraduate Honors Theses

While the fields of physics and international development may seem disparate, the insights gained from studying each one of them can improve understanding of the other. Here, I demonstrate that concept as applied to computational optics and historical memory. Thus, the purpose of this project is threefold: (1) to computationally model light transport through tissue, and use that model to inform choices about a physical system; (2) to determine the types of historical memory recommended in the final reports of truth commissions; and (3) to give evidence for the usefulness of human-centered design in both areas. To model light transport, …

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Terwilliger Algebras For Several Finite Groups, Nicholas Lee Bastian Mar 2021

Terwilliger Algebras For Several Finite Groups, Nicholas Lee Bastian

Theses and Dissertations

In this thesis, we will explore the structure of Terwilliger algebras over several different types of finite groups. We will begin by discussing what a Schur ring is, as well as providing many different results and examples of them. Following our discussion on Schur rings, we will move onto discussing association schemes as well as their properties. In particular, we will show every Schur ring gives rise to an association scheme. We will then define a Terwilliger algebra for any finite set, as well as discuss basic properties that hold for all Terwilliger algebras. After specializing to the case of …

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Telsam-Target Protein Fusions Can Form Diffraction-Quality Crystals Without Direct Inter-Polymer Contacts, Moriah Longhurst Mar 2021

Telsam-Target Protein Fusions Can Form Diffraction-Quality Crystals Without Direct Inter-Polymer Contacts, Moriah Longhurst

Undergraduate Honors Theses

X-ray diffraction is a robust method for determining the detailed 3D structures of specific proteins. However, this requires the formation of well-ordered protein crystals, a process that is time-consuming, expensive, and only has about a 10-30% success rate. New methods are needed to enable the efficient crystallization of challenging proteins. One such technique is explored here, which utilizes a protein polymer (the sterile alpha motif domain of the human protein translocation Ets leukemia, or TELSAM) as a crystallization chaperone to form a more ordered crystal lattice of target proteins and drive crystallization. This method was successfully used to crystallize, collect …

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Computational Development Of A Miniature Quantum Dot Spectrometer For Use In Space, Joseph Richardson Mar 2021

Computational Development Of A Miniature Quantum Dot Spectrometer For Use In Space, Joseph Richardson

Undergraduate Honors Theses

Miniature spectrometers are of great interest to NASA as necessary instrumentation is scaled down and optimized for specific space application. Semiconductor nanocrystals called quantum dots (QD) are being used to create a miniature high-resolution filter-based spectrometer, with the goal of use in space within 5 years. Computational imaging techniques— such as automated image analysis and mathematical spectrum reconstruction algorithms—are key to making the QD spectrometer a reality. This thesis will discuss the process of developing these computational methods, along with the improvements that have occurred from previous work.

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Realium: Building The Future Of Real Estate On The Blockchain, Demitri Haddad Mar 2021

Realium: Building The Future Of Real Estate On The Blockchain, Demitri Haddad

Undergraduate Honors Theses

This paper discusses the prospective challenges, limitations and opportunities in the real estate sector for blockchain. It outlines the idea of Realium, a financial technology application that aims to assist in the purchase, sale, and legal compliance of real estate assets. For more information see docs.realium.io

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Engineering Cell-Free Protein Expression Systems For Biotherapeutics And Biosensing, John Porter Hunt Mar 2021

Engineering Cell-Free Protein Expression Systems For Biotherapeutics And Biosensing, John Porter Hunt

Theses and Dissertations

Therapeutic proteins have become a cornerstone of modern medicine since the FDA approval of recombinant human insulin in 1982. Likewise, biosensors transform chemical detection and disease diagnostics by identifying biomarkers, chemical contaminants, and infective agents. Long-standing methods for creating therapeutics and biosensors employ whole cells such as Escherichia coli (E. coli). Alternatively, cell-free protein synthesis (CFPS) employs the enzymatic reactions necessary for protein production and biosensing within a cell, but in an engineered reactor environment facilitating unprecedented access to and control over biochemical machinery, preservation by cryodesiccation for portable deployment, and functionality in cytotoxic applications. This dissertation reports advances in …

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