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THE EFFECT OF COVID-19 PANDEMIC ON U.S. BEEF EXPORTS TO ITS MAJOR TRADING PARTNERS
Get PDFThis study analyzed the effect of COVID-19 on U.S. beef exports to South Korea, Japan, China, Mexico, and Canada between June 2017 and July 2023. After accounting for potential factors influencing exports, the study finds that the pandemic’s impact was different in both magnitude and persistence among major trading partners. The drop in exports to Japan and Mexico were notable during the pandemic. The decline in exports began early in the year for Mexico and in March for South Korea. Exports to Canada on the other hand both increased and decreased during this period. Exports to China followed a different pattern and increased during the first six months of the pandemic. Exports to all major export markets recovered as the effects of the pandemic eased by the end of May and fully recovered to pre-pandemic levels by the end of the year. Post-pandemic export volumes have been steady in all major markets amidst the seasonal fluctuations except for Mexico. A confluence of factors including the per capita GDP of the importing country, the exchange rate, trade agreements, time trend, and seasonality influenced U.S. beef exports during the study period. In conclusion, the study reveals the complexity of bilateral trade and importance of accounting for other confounding influences when measuring the impact of the pandemic on U.S. beef exports
The Russian Orthodox Church and Russia\u27s Military Nuclear Complex: A Time Series Analysis
Get PDFIn recent years, the relationship between the Russian Orthodox Church and the Russian military has garnered significant scholarly attention. Notable contributions from Adamsky (2019) and the Garrards (2008) assert the integral nature of this relationship. This research paper builds on this research by examining the relationship between the level of Orthodox religiosity in the Russian public and the Russian nuclear complex. This research provides a foundational step towards a deeper understanding of the Russian Orthodox Church’s navigation within Russia’s religious market. The primary objective is to better understand the connection between the Russian Orthodox Church and Russia’s military-nuclear complex. The research paper begins with an overview of Russia’s religious market and a review of the extant literature on the church-state relationship in Russia. This literature offers several hypotheses for the relationship between the public’s involvement and support for the Russian Orthodox Church and Russia’s military, specifically its nuclear program. I test between these hypotheses using a novel measure of Orthodox religiosity. I employ time series analysis to investigate the existence of a cointegrated relationship between this measure and Russia’s nuclear-military complex. I find evidence of a cointegration, which suggests that levels of Orthodox beliefs and practices move through time with changes in the military. Further analysis using error correction models reveals that this relationship is not causal. This indicates an underlying process influencing both series. The study concludes with a discussion of the implications and final remarks
LEFT OR RIGHT: DISENTANGLING THE RELATIONSHIP BETWEEN POLITICAL IDEOLOGY AND SERVICE QUALITY EXPECTATIONS
No full textCustomers’ service quality expectation is an important antecedent of their satisfaction, loyalty, and brand perception. Despite their importance, there is limited empirical research on the factors influencing these expectations. This dissertation attempts to address this important gap by exploring the role of political ideology on service quality expectations. This research proposes and examines political ideology, for which fairly accurate and objective data can be obtained, as a novel predictor of customers’ service quality expectations. Across three studies conducted in various settings, I consistently found that political ideology significantly influences service quality expectations. Specifically, the findings show that conservatives generally have higher expectations for service quality compared to liberals. Moreover, the specific dimensions of service quality expectations (tangibles, reliability, responsiveness, assurance, and empathy) are impacted differently by political ideology depending on the service context. Furthermore, the research identifies three key mediators, entitlement, industriousness, and optimism, through which political ideology influences service quality expectations. The manuscript concludes by discussing the contributions of these findings, their practical implications for managers and practitioners, and potential directions for future research
ESSAYS ON MOBILE MONEY ADOPTION AND HOMEOWNERSHIP DYNAMICS: CONSUMPTION PATTERN, MONETARY POLICY, AND RISKY ASSET CHOICE
No full textThe inexorable rise of mobile money innovation has led to huge changes in consumption and saving decisions for many households across developing economies. With this background, we use the Ghana Socio-economic Panel Survey (GSPS) data to explore the relationship between mobile money usage and household consumption and savings decisions. Firstly, we develop a framework in which mobile money shifts the budget constraint of households through the transaction cost and remittances in a dynamic setting. Secondly, we show through our empirical results that mobile money promotes household consumption, concluding that the payment convenience of mobile money improves household income by reducing transaction costs and enhancing remittance receipt, thereby promoting consumption growth. A heterogeneity analysis showed that households with larger assets, higher income, relatives overseas, residing in high-income regions, and low financial literacy experienced larger facilitating effects of mobile money on consumption than their counterparts. Meanwhile, households with fewer assets, lower income, no relatives abroad, lower financial literacy, and lower-income regions experience a greater facilitating effect of mobile money savings. Regarding consumption structure, mobile money innovation mainly promoted non-recurring household expenditures rather than recurring ones. Further analysis of consumption categories shows that medical care expenses, communication, food, and fuel expenditures are among the most affected household expenditures by mobile money use. In chapter 2; Given that monetary policy works on the interface of financial systems, fintech innovations can lead to an instability of the money demand function which affects the price level or aggregate spending and consequently, inflation. Therefore, mobile money innovation impacts not only household finance and consumption but also has monetary effects, especially on inflation and real growth. We investigated the impact of mobile money innovation on monetary policy; namely the stability of the money demand function, and output gap using panel data from 44 developing countries and the Generalized Method of Moment Technique. First, we show that there is a weak negative association between the trend of mobile money and the income velocity of money. Further analysis found a positive and statistically significant impact of the innovation on the output gap and a negatively significant effect on the money demand function. We conclude that there are countervailing effects where mobile money lowers transaction costs, improves productivity and economic efficiency, and increases output, resulting in a lesser inflationary effect. In Chapter 3; we show although numerous studies have examined the crowding-out effect of housing on portfolio choice via the house price risk channel and the liquidity constraint channel, separate analyses distinguishing risky asset choices and drawing a distinction between committed and non-committed mortgage payment under homeownership types has received less attention. We investigate the heterogeneous impact of homeownership type on risky asset choice using the 2021-2022 Survey of Economics and Household Decision-making. First, we show that homeowners with mortgage debt are less likely to participate in the cryptocurrency market compared to the stock market indicating that the higher risk associated with “speculative assets” likely induced homeowners with mortgage debt to adopt a more cautious approach to selecting their risky portfolio. The debt component separating homeowners becomes even more compelling when the risk level between assets varies significantly larger, and the agents’ incomes are lower than a certain threshold. However, changes in housing market conditions significantly change the temperance exhibited by homeowners towards risky asset selection. We further decomposed the effects across age groups, risk profiles, and income groups. In addition, we examined the crowding-out effect of house prices and liquidity constraints associated with homeownership as compared to renting. The empirical evidence shows that homeowners are less likely to participate in both the stock market and the cryptocurrency market as compared to renters due to house price risk and liquidity constraints associated with homeownership
IDENTIFYING THE GEOGRAPHICAL RELATIONSHIP OF CLIMATE CHANGE PERCEPTIONS IN MIDDLE AND HIGH SCHOOL STUDENTS WITHIN THE UNITED STATES
No full textA large and growing body of research has provided a comprehensive understanding of the current adult generations’ beliefs relating to climate change, but what about the younger generations growing up in a time of climate crisis? Younger generations will be more burdened by the increasingly severe effects of climate change due to its temporal progression. As the younger generations experience these effects, they will have a better understanding of how to mitigate and adapt to them. To better understand this, we conducted a multivariate hierarchical linear regression model to examine the extent to which 1) county-level social, geographic, and biophysical factors and 2) individual-level demographic and socio-psychological factors influenced adolescents’ climate beliefs and risk perceptions. We obtained our data though an online survey of 226 middle school and high school students from across the United States and county-level data sourced from the US Census Bureau, the Yale Climate Opinion Maps, and Four Twenty-Seven. Preliminary results suggest that the most influential factor that leads to a better understanding of climate change is not necessarily geographically based, but rather through interpersonal communication about climate change in the adolescent’s personal life. This research informs our understanding of how younger generations can be influenced to make better decisions relating to climate change and other environmental issues that would require a long-term collective approach to solve
Effect of Micronized Rubber Powder on High Plastic Clay Stabilized with Cement Kiln Dust
No full textCement Kiln Dust (CKD) and Micronized Rubber Powder (MRP) offer sustainable solutions for soil stabilization, addressing both environmental and engineering challenges. CKD, a byproduct of cement manufacturing, is rich in pozzolanic materials that can enhance clayey soil properties by reducing plasticity and increasing strength. This makes CKD a valuable additive for improving the load-bearing capacity and durability of clayey soils used in construction. MRP, derived from end-of-life tires, contributes to sustainability by recycling waste rubber and adding ductility to treated soils. The incorporation of rubber waste not only helps in reducing the environmental burden of tire disposal but also enhances the flexibility and resilience of the stabilized clayey soil. Utilizing these industrial by-products in soil stabilization not only mitigates waste disposal issues but also promotes the development of resilient and eco-friendly construction materials, making them highly beneficial for sustainable infrastructure projects.The present study investigates the effects of various mix proportions of CKD and MRP on Carbondale soil, a high plastic clay. The soil was stabilized with CKD in proportions of 7%, 14%, and 21%, and MRP in proportions of 0%, 2.5%, 5%, and 10% of the dry unit weight of clayey soil. Comprehensive laboratory tests were conducted, including particle size distribution, Atterberg limits, compaction characteristics using the miniature Proctor, unconfined compressive strength (UCS), ultrasonic pulse velocity (UPV), and resilient modulus (RM). The RM test assessed the soil\u27s elasticity under repeated loading, simulating traffic conditions to evaluate the material\u27s performance in pavement design. These tests aimed to determine the optimal mix proportions that would provide the best combination of strength, stiffness, and durability for use in various geotechnical applications. Results from different tests showed that the addition of MRP significantly altered the properties of the CKD-stabilized soil mix. The miniature Proctor test revealed that the addition of MRP reduced the maximum dry density (MDD) of the mix and slightly increased the optimum moisture content (OMC) of the soil mix, indicating a change in compaction characteristics. From the UCS test, it was observed that while the addition of 2.5% MRP to the CKD soil mix reduced the overall strength, it absorbed considerable amount of strain. Specifically, for soil mixed with 7% CKD, the inclusion of 2.5% MRP absorbed over 60% more strain, despite a 50% reduction in strength. Similarly, the mix with 21% CKD and 2.5% MRP showed a 30% increase in peak strain with a strength reduction of up to 40%. The resilient modulus values indicated that the addition of MRP to the soil mix resulted in strain softening, leading to decreased RM values. The soil mix with 7% CKD and 2.5% MRP showed almost no gain in RM values across all curing periods due to strain softening effects. However, the regression analysis between predicted and experimental RM values showed a positive correlation, with a coefficient of determination (R2) ranging from 0.7 to 0.96, indicating a reliable predictive model for RM based on the tested parameters. These findings highlight the trade-offs between strength and stiffness in CKD and MRP-stabilized soils, offering insights for optimizing soil stabilization techniques in sustainable construction practice
ADVANCEMENTS AND CHALLENGES IN THE INTERSECTION OF MACHINE LEARNING AND IOT SECURITY
No full textThe proliferation of IoT devices in various sectors, such as healthcare, industrial systems, and residential areas, presents unique security vulnerabilities that conventional security frameworks struggle to address. This research explores how ML techniques can be leveraged to enhance IoT security, offering adaptive, robust, and efficient solutions. A thorough literature review identifies the intersection of ML and IoT security, emphasizing the need for dynamic and resilient security mechanisms that can anticipate and mitigate emerging threats. The study presents several case studies, including the deployment of ML in securing smart home systems and healthcare infrastructures, demonstrating the practical application and benefits of integrating ML into IoT security frameworks. Significant findings from these case studies illustrate the effectiveness of ML-driven security systems in detecting anomalies, enhancing data protection, and providing real-time threat detection. However, challenges such as data scarcity, privacy concerns, and the need for continuous model refinement remain prevalent. The thesis contributes to the academic and practical understanding of IoT security by providing detailed insights into the current capabilities and limitations of ML applications in this area. It also outlines future research directions focusing on the development of advanced ML algorithms, privacy-preserving techniques, and standardized approaches for improving the security and efficiency of IoT system
NOVEL SYNTHETIC AND EXPERIMENTAL APPROACHES FOR CREATING 13C- AND 15N- HYPERPOLARIZED MOLECULES VIA SABRE-SHEATH
No full textNuclear magnetic resonance (NMR) is a powerful tool for collecting information on molecules that cannot be easily observed using other technologies. Although extremely powerful, NMR is not without flaws. First, because NMR relies on magnetism and other quantum properties such as nuclear spin, NMR is only compatible with particular nuclear isotopes—many of which that do not have large natural abundances, contributing to low sensitivity for both NMR and magnetic resonance imaging (MRI). Second, the low sensitivity problem is greatly exacerbated by the ordinarily small differences in the populations of the nuclear spin states—i.e., low nuclear spin polarization (and hence, detectable nuclear magnetization). To help remedy the low sensitivity of NMR and MRI, many methods of exploiting “tricks” from physics have been developed. Dynamic nuclear polarization (DNP), spin exchange optical pumping (SEOP), parahydrogen induced polarization (PHIP), and signal amplification by reversable exchange (SABRE) are all “hyperpolarization” methods that exploit such tricks of physics to reach signal levels in NMR and MRI that would otherwise be impossible for the involved substances and isotopes. This thesis is organized into 3 chapters. The first chapter offers insight into the background concepts of NMR and MRI technology, covering topics such as: spin, chemical shifts, and J-coupling. This chapter also touches more on the low sensitivity of NMR and why it is problematic, as well as introducing the idea of signal enhancement methods like hyperpolarization, including its limitations. Chapter 2 discusses each of the hyperpolarization techniques in detail. This chapter also serves as a brief history of hyperpolarization techniques, as each section is organized roughly in a chronological order, taking the reader through the limitations and breakthroughs of each technology. SABRE and SABRE-SHEATH are some of the last sections of this chapter and most relevant to the works in this thesis, thus serving as a segue into chapter 3. Chapter 3 (the final chapter) comprises a summary of findings within this thesis, with a heavy emphasis on synthetic methods and procedures developed and used to produce selected agents required for the involved SABRE experiments to work. Chapter 3 is a culmination of many years of research, and is organized into 3 subsections each summarizing work with the sub-branches of SABRE agents studied here: so-called cleavable substrates; long-chain hyperpolarization agents; and symmetric di-imidazole substrates. Except where stated otherwise, the agents detailed within were devised with the goal of one day being used within a pre-clinical or clinical MRI setting. As such, the agents selected have biologically relevant counterparts; the underlying physiological reasoning behind their designs are provided in the cleavable substrates section. This final chapter concludes with additional thoughts and suggestions for future researchers looking to continue this work, also including some findings while compiling this discussion that do not fit elsewhere
DEVELOPMENT OF A RESPONSE SPECTRUM MODEL FOR BIFENTHRIN USING JUVENILE CHINOOK SALMON (ONCORHYNCHUS TSHAWYTSCHA)
No full textLong-term declines in salmonid populations observed in California Central Valley have prompted efforts to enhance the understanding of how environmental stressors impact sensitive species. Bifenthrin, a current-use insecticide, has been consistently detected throughout the Sacramento-San Joaquin River Delta (Delta) and has been linked to detrimental effects in salmon. Traditionally, aqueous concentration is used in toxicological studies to evaluate the effects of pesticides on aquatic organisms, which assumes that concentration of the toxicant in water is a valid surrogate for dose. The critical body residue approach was established as an improved technique for assessing toxicity of hydrophobic contaminants, but there is a lack of data to support the application of this method in assessing risk of contaminant exposure in the environment. The current study creates a response spectrum model (RSM) demonstrating the relationship between internal residue and effects observed in Chinook Salmon from laboratory-based exposures. To develop the RSM, a series of behavioral and physiological endpoints were measured using bifenthrin-dosed Chinook Salmon to use with previously generated mortality data for incorporation in the model. The most sensitive endpoints were locomotion and shoaling behavior, followed by anxiety, growth, swim performance, upper thermal sensitivity, olfactory response, and lethality. The RSM endpoints were compared to bifenthrin residues in field-collected juvenile Chinook Salmon collected in 2019-2020 as part of our earlier studies. We found bifenthrin tissue residues were at similar levels to the most sensitive endpoints featured in the RSM, suggesting that bifenthrin exposure in the field is likely to cause behavioral effects to salmon as they out-migrate through the Delta. The developed RSM is a tool that could be used by water quality managers to evaluate the extent to which bifenthrin exposure may impact behavior and performance in juvenile salmon, providing a field-based verification of its effects on outmigration