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Relationship between Community Structure of Frugivorous Mammals and the Provision of Ecosystem Services in the Peruvian Amazon
No full textThis work is embargoed by the author and will not be publicly available until May 2029.The southern Peruvian Amazon, one of the most biodiverse places on Earth and home to many indigenous communities, provides multiple ecosystem services (ES). Frugivorous mammals play an essential role in the functioning of the ecosystem as seed dispersers, contributing to the survival of many utilitarian plants. However, changes in forest demographics and technological developments increase pressure on these animals. Though changes in the community structure of large vertebrates affect ecosystem functioning, the relationship between mammal diversity and the benefits they provide is not well known, and trade-offs between provisioning ES have not yet been studied in the field. This dissertation aims to highlight the importance of the diversity of frugivorous mammals in relation to the provision of ES relevant to local communities in the Peruvian Amazon. I examine the relationship between the community structure of frugivorous mammals and the ES of wild meat, wild fruit, and raw material provision. To do this, I sampled arboreal and terrestrial mammals and wild edible and utilitarian (WEU) plants, and evaluated the ES through questionnaires in three indigenous communities: Infierno, Boca Pariamanu, and Masenawa, and three protected areas: Refugio Amazonas, Hoja Nueva 2, and Los Amigos in Madre de Dios, Peru. My results included the following. First, protected areas presented higher arboreal mammal diversity than Indigenous lands, but no difference was found in terrestrial mammals and WEU plants. The sapling density of WEU plants was positively related to frugivorous mammal diversity, both arboreal and terrestrial, and functional group richness. Second, the potential productivity of wild meat was similar in Indigenous and protected areas although protected areas presented more potential productivity of wild fruit and raw materials than Indigenous lands. The potential productivity of wild meat, wild fruit, and raw material increased with frugivorous mammal species and functional diversity. Third, my results showed no trade-offs between the provision of wild meat and the provision of wild fruit and raw material in any study site. In conclusion, the state of wild meat, wild fruits, and raw materials in Indigenous communities reveals the need to adopt sustainability management plans for heavily used plant and animal species. These results highlight the importance of frugivorous mammal diversity in plant regeneration and the provisioning of ES.2029-05-1
Using Goal Setting with Self-Monitoring Technology to Increase On-Task Performance in Students with Attention Difficulties
Full text linkStudents with Attention Deficit Hyperactivity Disorder (ADHD) have difficulty maintaining their focus during class lessons and often require reminder prompts from an adult including a teacher or instructional assistant. This study used goal setting paired with a technology-based application and Smartwatch to explore increases in elementary student on-task time during math class. The study sought to answer the question if a functional relationship existed between goal setting with the use of the Smartwatch to self-monitor and an increase in on-task time during math lessons. Secondary questions focused on determining if a functional relationship existed between self-monitoring and an increase on class assessment scores and an effect on student and teacher perceptions of attention concerns and pro-social behaviors. A feedback loop for self-regulating behavior including identifying a need, setting a goal, self-monitoring towards that goal, and then self-reflecting on their progress and performance was implemented within the intervention. The study’s design was a single case, A-B-A-B withdrawal design used with 6th grade elementary age students (n = 4) with ADHD or attentional concerns. The students self-monitored with Smartwatches along with the Strides application during their math class in the general education classroom in a team-taught environment. The study evaluated the effect of goal setting with a self-monitoring application using Smartwatches had on 6th grade students’ on-task time during math class. The study also evaluated the effect of goal setting with a self-monitoring application using Smartwatches on 6th grade students’ performance in accurately solving mathematical problems following a class focus lesson. Finally, the study evaluated the effect of the self-monitoring strategy on student classroom, emotional, and social behaviors during the math focus lessons. Data gathered included responses on emotional and social behavior scales, observational data regarding on-task time, and end of lesson math assessments. Data was analyzed using visual analysis regarding the six single case design features of mean, standard deviation, variability, trend, immediacy of effect, and percentage of data exceeding the mean for both the on-task time percentages and the score on the mathematics assessments. Mean scores of on-task times along with level and trend were analyzed within each phase and across phases. The results demonstrated a functional relationship between the use of the self-monitoring technology and on-task time during math classes. The students all met the pre-established goals for increased on-task time during the self-monitoring phase. The responses from both students and the teachers also indicated that the intervention led to improvement on the students’ classroom social and emotional behaviors. The study did not establish a relationship between increases in on-task time and performance on daily math assessments. Implications for practice include using Smartwatches to increase student on-task time within the general education classroom without additional adult support. Using this technology can aid the development of independent self-awareness skills of attention. Additional research is needed to further explore the effect of self-monitoring on student achievement scores. Longer intervention times should be conducted to determine if the effects of using the self-monitoring technology are maintained and generalized across academic lesson units.Keywords: self-monitoring, technology, ADHD, goal setting, elementar
Inhibition of TC-83 Alphavirus by Small Molecule Saracatinib and Piscidin Peptide Candidates
Full text linkVenezuelan Equine Encephalitis Virus (VEEV) is an encephalitic alphavirus that is known to cause disease in the central nervous system (CNS). It is naturally transmitted by infected mosquitoes and causes disease in equines and humans on a regular basis in various parts of the world. VEEV also has the potential to be aerosolized, and when infection is acquired via the respiratory route, the chances of CNS penetration are higher, with increased incidences of morbidity and mortality. Even if infected individuals clear the infection, there is a potential for long term neurological sequelae in survivors, thus increasing the disease burden. There are currently no FDA-approved therapeutic intervention strategies to treat the encephalitic manifestations of VEEV infection-induced disease. This thesis project focused on establishing early stage efficacy measurements for a candidate small molecule inhibitor, Saracatinib, which is already FDA-approved for the treatment of cancer. In addition, this project also involved screening a small library of synthetic antimicrobial peptides (AMPs) derived from a parent piscidin peptide. Piscidins are fish-derived, naturally occurring AMPs that have been demonstrated to have antibacterial and immunomodulatory properties. My project was based on the hypothesis that Saracatinib and synthetic piscidin-derived AMPs will demonstrate antiviral activities against VEEV. This project was performed using the attenuated TC-83 strain of VEEV, in the context of several human-derived cell lines of the blood brain barrier (BBB). Analysis of antiviral activities of Saracatinib in the nontoxic range demonstrated that endothelial cells were highly responsive to treatment and showed significant reduction in viral load in treated cells. Screening of the synthetic piscidin library has identified four candidates that showed a statistically significant reduction in viral load in a human astrocyte cell line. Cumulatively, these data provide the foundation for further development of Saracatinib and prioritized synthetic piscidin AMPs as therapeutic intervention strategies against VEEV infection
A New Approach to the Development of Cryptographic Hardware Based on Specialized Computer-Aided Design Tools
Full text linkThis research looks to provide a new approach to the development of cryptographic hardware by providing specialized computer-aided design tools. Specifically, when working with cryptographic algorithms, there are number of operations that can take a significant amount of time. Many researchers have to manually develop a scheduler of operations to allow their implementation to efficiently implement the algorithm. This requires both an understanding of the underlying cryptosystem and the mathematical functions that have to be applied throughout the algorithm. This research presents a generic mechanism for converting the algorithms into the underlying commands for the cryptographic hardware. We show how this implementation can be used to implement algorithms with performance approaching custom-designed hardware. We also provide the framework for developing real-time configurable implementations using new FPGA-like lookup tables within ASICs. Finally, we provide an extensible LLVM-based model for the framework that can be used by future implementers, with a focus on isogeny-based cryptosystems
Three Essays on Business and Politics in Adam Smith
Full text linkThis dissertation explores nascent themes of Theory of the Firm and Public Choice in Adam Smith’s writings. The first chapter argues that Smith conceives of a framework for moral entrepreneurship based on prudence in Theory of Moral Sentiments. The second chapter argues that many of the puzzling aspects of Smith’s commentary on joint-stock companies can be clarified when we examine them through the lens of Smith’s “impartial spectator” theory. The third chapter argues that Smith is not merely a forerunner of behavioral economics, but also of behavioral political economics, which is a growing field that applies the tools and insights of behavioral economics to political actors
Political Leadership in Autocracies: Impacts on Democratization and International Cooperation
Full text linkThis paper is a capstone research project in Global Affairs.Scholarly work on the dynamics of autocratic leadership and its impact on international cooperation has increasingly challenged conventional assumptions about democratization and governance. This research contributes to the literature by examining the role of political leadership within autocratic regimes from 2006 to 2024, assessing how varying degrees of democratization influence international cooperation. Building on Geddes' typology of autocracies, personalist, military, and single-party, this study introduces Wiatr’s hybrid regimes to highlight the evolving nature of authoritarian governance. This research argues that regimes with greater democratization traits, such as accountability and policy flexibility, are more adept at engaging in international cooperation. Using data from the Bertelsmann Transformation Index (BTI), this research quantitatively analyzes the relationship between democracy status and international cooperation across 1,297 observations
A TALE OF TWO LITERACIES: AN INTEGRATED COMPUTER SCIENCE CODING AND WRITING INSTRUCTION
Full text linkThe push to teach coding in schools continues to gain momentum. Coding helps students develop skills in problem-solving, critical thinking, and creativity, as well as improve overall academic performance. However, students with disabilities often face challenges in areas such as problem-solving, mathematics, and multistep reasoning when learning to code. Moreover, teachers may lack the time or proper training to effectively teach coding as a standalone subject to students with disabilities. To address these challenges, this study explores an integrated approach to teaching coding within the context of writing, due to the similarities between the two subjects. The purpose of this study is to examine whether a functional relation exists between integrated instructional coding/writing lessons, along with the use of a technology-based graphic organizer, and improvements in coding and writing skills for six upper elementary/middle school students with HID. The dependent variables included (a) speech blocks, (b) instances of sequencing, (c) central messaging, (d) the number of special effects, (e) the inclusion of a topic sentence, (f) the inclusion of supporting sentences, and (g) the inclusion of a summary sentence. This single-case multiple-baseline across participants study was conducted in a public charter school setting in the mid-Atlantic region of the United States. Results from this study show that upper elementary/middle school students with HID can greatly benefit from instructional lessons on coding/writing alongside a technology-based graphic organizer to improve coding/writing skills. Strong evidence of a functional relation between the independent and dependent variables was demonstrated for most measures, with the exception of moderate evidence of functional relation for central messaging and special effects measures. Implications and limitations are also discussed, along with where future research should be headed
Exceptional Mathematics Teachers' Beliefs about the Nature of Mathematics and Teaching and Learning
Full text linkTeachers' beliefs have been shown to play a fundamental role in their choices for instruction, task selection, and pedagogical decisions (Beswick, 2019; Cross Francis et al., 2014; Kertil et al., 2021; Šapkova, 2014). When asking teachers to align their practices with those envisioned by educational reformers (e.g., NCTM, 1989; NGA Center & CCSSO, 2010), teacher educators and professional developers must address teachers' underlying beliefs about the nature of mathematics (NOM) and teaching and learning. This qualitative explorative case study aimed to identify exceptional mathematics teachers' beliefs on the nature of mathematical knowledge teaching and learning. Exceptional middle school mathematics teachers in this study were recipients of the Presidential Award for Excellence in Mathematics and Science Teaching (PAEMST). PAEMST recipients are nationally recognized for using constructivist mathematics instruction that supports student learning through inquiry-based and student-centered instruction. A blended theoretical framework based on Earnest (1998) and Schommer-Aikins (2004) was employed to examine teachers’ beliefs and the relationship between their beliefs about NOM and teaching and learning, if and how their beliefs have evolved throughout their teaching career, and the contextual factors that were influential in the evolution of their beliefs. Teachers in this study were unfamiliar with the term but did provide a definition when asked about the source, structure, and stability of mathematical knowledge. Exceptional teachers' beliefs about the NOM evolved over their careers, from seeing mathematical knowledge as fixed and authoritative to seeing it as a dynamic discovery process involving nature and patterns. This shift in their beliefs about the NOM paralleled their teaching practices, emphasizing interconnectedness, independent problem-solving, and critical thinking, aligning with a Problem-Solving paradigm. Teachers identified the learning experiences that strongly influenced the change in their beliefs as those that fostered a deep understanding of mathematical concepts, often through targeted professional development. The implications for mathematics teacher education and professional development are discussed
DECISION SUPPORT FOR DESIGN SYNTHESIS MODELED AS A PARTIALLY OBSERVED MARKOV DECISION PROCESS
Full text linkThe purpose of this research is to improve the incorporation of risk management within the engineering design process. Current practices incorporate preliminary risk assessment but do not treat risk management holistically across system design and synthesis. Additionally, while most synthesis practices include pro forma verification activities, they do not provide guidance on the relative values of those activities, resulting in simultaneous generation of excess costs and false verification that the system meets requirements.The focus of this research is to demonstrate a proof-of-concept means of training decision support agents that will assist in optimally selecting design synthesis activities in a way that incorporates balanced risk avoidance, risk acceptance, and risk mitigation, including the costs (and value) of necessary verification activities. To that end, I have investigated the following hypotheses to test with this research: • Embedding the expected costs of system failures into a design’s state value function up-front will increase the likelihood of performing synthesis activities directed towards implementing risk mitigating features or of not performing synthesis activities directed towards implementing features that should be avoided. • Enforcing partial observability of the synthesis state when training decision support agents increases the relative value of performing verification activities. • Training a decision support agent against a design synthesis program will allow for one to determine, under various conditions, the relative preference of low-cost, low-accuracy testing to that of high-cost, high-accuracy testing. The proof-of-concept simulates synthesis of design specifications using a partially observed Markov decision process (POMDP). These simulations were then used to train decision support agents by means of reinforcement learning (RL) and approximate dynamic programming (ADP). After training, the agents were evaluated by recording their policy preferences given an observation of the design synthesis state. The results of the research demonstrated that agents trained in this way do decide to engage in risk avoidance activities as well as risk acceptance and mitigation, confirming the first hypothesis. However, there is not currently strong evidence to support the second or third hypotheses as the agents trained thus far rarely select to perform validation activities. The contributions of the research are as follows. This research provides a means to advance our understanding of the relative value of performing different verification activities at various points in the implementation of a feature in relation to sensitivity, specificity, and cost. And finally, this research advances the practice of risk management in design synthesis by demonstrating a method for optimally choosing between risk acceptance, mitigation, and avoidance during the design synthesis decision-making process
Us Against When: Futures and Complexity-Informed Conflict Transformation in the United States
Full text linkPeacebuilding practitioners in the United States comprise a sensemaking community that is grappling with multiple approaches to making positive change in the United States. Each organization and practitioner brings a set of methods to address that problem and an ideal audience that they believe should be the locus of change. The Us Against When project partnered with the Horizons Project and Common Ground USA to develop an image of a more peaceful United States and test how a peacebuilding scenario resonated with these organizations’ audiences. The research addressed the following question: How can a complexity-informed sensemaking approach help United States-based peace organizations align their image of the desired future with their constituents and improve practice by utilizing sensemaking data to inform decision-making in their programming? Sensemaking activities included interpretation of the scenario in the SenseMaker tool, participatory sensemaking process, and early feedback from the organizations about the ways the resulting insights informed their decision making. The peacebuilding scenario was interpreted by over 800 respondents in five states at higher risk for political violence (Arizona, Texas, Georgia, Pennsylvania, and Ohio). The research’s experimental approach demonstrated how techniques from futures studies and complexity science could contribute to the ability of peacebuilders to construct sensemaking feedback loops and better orient their practice in complex conflicts