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A New 3d Modeling Method Reveals the Complex Membrane Topology of a Cardiomyocyte Mitochondrion
Get PDFThe mitochondrial inner membrane geometry is linked to its function as the locus of aerobic metabolism and diverse cellular processes in eukaryotic cells. Further comprehension of the IM morphologies requires sampling a range of IM topologies which include the complex features of a cardiac mitochondrion. To accomplish this task, Transmission electron microscopic (TEM) tomography is necessary to reconstruct the said mitochondria. Previous studies and experiments have paved the way to maximize its usage including the processes involved in post-production of tomograms. These methods vary and depend on the desired analysis. Feature extraction from TEM tomograms involves a series of filtering algorithms that have been developed for this purpose. Many of these algorithms have been sufficient for simpler geometries but additional filtering is needed for more complex shapes. Traditional methods require the laborious manual tracing of 2D slices of tomograms. The primary goal of this study is to develop a method for building 3-dimensional mesh from TEM tomograms of epoxy-embedded and stained mouse cardiac muscle with the goal of 3-dimensional modeling suitable for simulation. This novel protocol is effective in isolating cristae structures and allowed for the categorization of cristae structures within a mitochondrion. In addition, the results yielded a regional structure morphology that reveals connections to mitochondrial bioenergetics. Being able to dissect this mitochondrion has revealed insights into mitochondrial structural dynamics and polarity that have not been rendered in high-resolution during the writing of this dissertation
Studying School Gardens as Habitat for Urban Butterflies and Outcomes of Involving Elementary School Students in Data Collection during a DC Summer Program
Get PDFSchoolyard gardens are increasing in cities to simultaneously provide students with experiential learning opportunities and local communities with increased food security. These gardens may also provide urban habitats for pollinators and opportunities for students to interact with urban wildlife. Here we assess how schoolyard gardens may provide habitat for large-bodied butterflies and discuss how they may be designed to support more butterfly diversity. Due to their charismatic nature and presence in urban spaces, butterflies can be a flagship species to reconnect urban residents with the natural environment. Therefore, we designed the project to be student-led and assessed students' participation in the data collection process. Three elementary schools with rising first and third-grade students observe and capture large-bodied butterflies in their gardens during the summer of 2022. The species richness and abundance at school gardens were compared to butterflies caught by researchers in a corresponding natural area near each school. An N-mixture model was used to estimate the correlation between tree canopy, site area, and impervious surface to eastern tiger swallowtail (Papilio glaucus) abundance. Results showed that swallowtail abundance was negatively related to the percent of impervious surface at a site regardless of the site's area and proportion of tree cover. Our results indicate that urban schools with limited green space can increase butterfly abundance by planting more vegetation around the garden and decreasing impervious cover. Student discussions provided program feedback and increased interest in butterfly ecology within urban environments. These results indicate that involving K- 12 students in urban ecological research within their school grounds may increase their awareness of interactions with nature
“THINGS HAVE CHANGED AROUND HERE”: PERCEPTIONS OF CRIME AND SAFETY IN RURAL SOUTHEASTERN KENTUCKY
Get PDFAlthough a sizable portion of the United States population resides in rural areas, until recently the state of scholarship concerning rural crime as a whole was scant, poorly developed, and dated (Donnermeyer et al., 2006; Donnermeyer, 2007; Weisheit & Donnermeyer, 2000). However, the last several years have seen a reawakening of interest in issues of rural crime and safety. Contrary to common misconceptions of rural areas as relatively crime-free, research indicates these areas likely experience higher rates than urban areas of certain crimes, including substance use/misuse and substance use-related crime, domestic abuse and intimate partner violence, and certain types of juvenile delinquency (Kuhns et al., 2007; Weisheit et al., 2006). Given the sparse but evolving state of rural crime scholarship, there is great value in conducting a nuanced investigation into the crime- and safety-related concerns of rural residents, and their thoughts on how these problems are best addressed.Using qualitative analysis of 54 interviews conducted with residents of three southeastern Kentucky counties (Bell, Clay, and Harlan), this dissertation investigates four research questions: 1) What are the primary crime and safety concerns of residents in this rural area? 2) What are residents’ specific concerns pertaining to substance use and substance use-related crime in this rural area? 3) According to residents, why do individuals (including juveniles/youth) become involved in substance use and other risky/criminal behavior? And 4) What do residents identify as the primary protective factors insulating individuals (including juveniles/youth) from involvement in substance use and other risky/criminal behavior? Analysis shows that residents are exceptionally concerned with substance use (particularly methamphetamine use and opioid misuse), drug-related theft, domestic violence, and child abuse. Regarding risk for criminal involvement, residents describe an interlocking constellation of factors: hopelessness, apathy, and boredom engendered by community decline, ready availability of the substances in neighborhoods, cultural attitudes permissive towards substance use, pervasive substance use among family members, friends, and neighbors, few opportunities for gainful employment, chemical dependency, and absence of accessible substance use intervention services. Conversely, when speaking about protective factors, residents describe a corresponding constellation of factors insulating individuals from criminal behaviors: engagement in prosocial recreational activities, strong prosocial peer, neighbor, and family relationships, participation in the legal economy, commitment to and success in education, and personal resilience. These risk and protective factors rarely occur in isolation; rather, they are component parts of entire sprawling webs of factors operating in and across community-level, group-level, and individual-level domains. A particularly important finding of this dissertation is that collective efficacy and social disorganization appear to operate in dual ways in this rural community as strong social ties among friends, families, and neighbors are both primary risk and protective factors for substance use and criminal involvement
Case Study of a Senior Health Official During and Following the COVID-19 Pandemic and Health Crisis
No full textOral presentation of master's thesis projectThis study examined newspaper articles concerning Dr. Anthony Fauci and COVID-19 before, during, and after recognition of the impact of the virus in the United States, and later declaration that the pandemic was over. Specific research questions focused on type of newspaper article, positive and negative content themes, and specific reputation or character attacks upon Fauci and his defense. The eight largest by subscription national and regional newspapers provided 150 articles drawn from early in the COVID-19 crisis, middle phases, and when it was declared over. Most articles (96 of 150) fell into the general reporting or news category, with 17 identified as opinion. Experimenter judgment and automated content analysis software found themes in descending frequency of COVID-19, Diversity and Society, Politics, General, Communication, Values, and Expertise. Character or reputational attacks included name calling, motivation questioning, and challenges to Fauci’s credibility and trustworthiness. To defend himself, Fauci used apologia and name calling or labeling. Future senior health officials may consider developing more robust communication strategies in future inevitable health crises to contend with uncertainty, communication fatigue, and seemingly inevitable reputational attacks
THE IMPACT OF ADDRESSING SOCIAL DETERMINANTS ON HEALTH OUTCOMES AMONG MEDICAID PATIENTS
Get PDFThe United States spends significantly more per person on healthcare than most other countries in the Organization for Economic Co-operation and Development (OECD), yet has some of the worst health outcomes. A leading reason for the inefficiency in US healthcare spending is that it concentrates its resources on treating clinical conditions that could have been prevented rather than addressing upstream factors that impact population health. Research has shown that social determinants of health have a substantial role in the health outcomes of individuals. To explore the impact of policies encouraging health systems to address social determinants, this study analyzed the impact of a Medicaid 1115 waiver, the Delivery System Reform Incentive Payment (DSRIP) program. The study used a quasi-experimental design, applying difference in difference and comparative interrupted time series regressions to assess whether the program improved all-cause readmission rates and preventable emergency department visit (PEV) rates. The study findings indicated that after accounting for temporal trends in outcomes between participating and non-participating hospitals, the DSRIP program did not impact readmission or PEV rates. This study underscores the importance of accounting for a control group when evaluating public policies. The study was also unable to confirm that investments in initiatives addressing social determinants of health will lead to better outcomes when compared to health delivery models that solely address clinical care. Further research is needed to directly associate social determinant interventions to health outcomes to ascertain whether such interventions will improve population health
Investigating Climate Change, Extreme Weather, Dust Storm, and Solar Energy Nexus over the United Arab Emirates
Get PDFClimate change in recent years has significantly impacted the world's weather conditions. The average temperature has increased, heat waves and droughts are intensified globally, and extreme weather events are triggered by climate change. One of the impacts of climate change on the weather system is the occurrence of extreme dust weather. Aerosols caused by dust and sandstorms over the Middle East and Arabian Peninsula are significant events that hit the region from time to time with differing intensities. Several natural and anthropogenic impacts corrupt atmospheric aerosols, such as smoke and biomass. Usually, meteorological variables such as temperature are influenced by dust events where remote sensing can monitor these phenomena and record them from outer space. NASA provides Moderate Resolution Imaging Spectro-radiometer (MODIS) to detect global aerosol from Aerosol Optical Depth (AOD). AOD can measure particles in the atmosphere, such as dust, pollution, and smoke, that block sunlight by scattering or absorption. Thus, AOD assists in observing dust storm events and tells us how much radiation is prohibited from reaching the ground surface. The primary purpose of the research is to study climate change in the United Arab Emirates (UAE), dust storms events that happened over the UAE in 2021, the meteorological parameters examined during the storms, extreme weather that dominates the region due to climate change, solar radiation in the UAE, and how dust storms events can affect the production of solar energy using multi-sensors. MODIS AOD merged Dark Target-Deep Blue data utilized to validate against Aerosol Robotic Network (AERONET) AOD in selected locations over the UAE. The climate change-extreme weather-dust storm-solar energy nexus system was applied to produce results. This research contributes to understanding climate change's impact on dust storms and how it affects solar energy production in the UAE
Carve the Past: Inferring Dates of File Fragments Using Nearby Allocated Files
Get PDFIn the last twenty years, technology has made immense progress, almost at an explosive speed. While this advancement has been good for the country in many ways, there are also some drawbacks. One of these is computer crime, which has become so widespread that present digital forensic methods are unable to keep up. As a result, the time it takes to examine a case is long and growing, and cases are not adequately investigated. This has resulted in an ever-increasing number of unresolved computer crime cases. One key attribute of failing cases is the lack of ability to reconstruct crime events. Often, an attempt is made to delete evidence in order to cover up traces, but there are still often many traces left behind that can help investigators reconstruct the past. Therefore, timestamps play a significant role in two main objectives: first, they serve as a primary culling criterion to reduce the amount of digital evidence subject to analysis, and second, they are the sole feature that allows for reliable reconstruction of timelines and helps to locate temporal anomalies. File fragments, normally from deleted or relocated content, are usually useful, especially when intact files are unavailable. However, these fragments rarely contain embedded timestamps or file-system timestamp information, which reduces their usefulness. This work investigates and proposes a framework for determining the time-window of deleted file fragments that are usually found in unallocated space and file slack. Using the known temporal state of neighboring clusters, it is possible to derive a date-and-time range for when the file fragment was first written to media until it was deleted. Event construction and sequencing are essential to the digital investigation process to develop a sound case and admissible evidence. Results of the empirical study suggest that the adjacent files' chronology provides an indication of the time-window of the deleted file fragments. The proposed framework can help digital forensic investigators with the event reconstruction process, which is critical in building a sound case and admissible evidence. By using the approach presented in this work, investigators can infer the time-window of deleted file fragments, which can be used in event reconstruction, to locate temporal anomalies, or for other investigative purposes
Bringing Order Out of Chaos: The Evolution of Soldiers’ Post-Battle Expectations during the Coalition Wars – Experiences of the Grande Armée at Eylau and Borodino
Get PDFAs war ravaged Europe in the wake of the French Revolution, the expanding scale of the conflict confronted European armies with new humanitarian and logistical challenges. In response, both the French and their enemies attempted to find ways to mitigate the worst excesses of this ‘modern’ war as well as make some moral sense of its unsettling realities. Although these efforts are usually overshadowed by the drama of combat and debates of strategy, post-battle activities such as the burying the dead, treating the wounded and clearing debris from the battlefield all helped determine not only the extent of a victory but also the moral meaning ascribed to a battle. Far from being inconsequential afterthoughts, the execution and observation of these activities provided experiences that helped shape military culture, war memory, and the conception of national identity
The Role of Human Capital in Economic Development
Get PDFEconomists have long recognized the importance of human capital in economic growth. In this series of papers, I study how various institutions of human capital formation affected economic development in a variety of contexts prior to 1900. These include both formal institutions of human capital formation such as universities and informal institutions such as apprenticeships. The first chapter examines the role of European universities during the late Middle Ages and early modern eras, starting with the creation of the University of Bologna in the late 12th century. These “formal” institutions of human capital focused on the teaching of law and supplied the civil service and justice systems of their home cities with trained legists. I find that cities which hosted universities had faster population growth than similar cities without universities, suggesting that universities were associated with higher levels of economic development. The second chapter contrasts the formal university with an informal human capital institution—the English apprenticeship. Though England was the cradle of Europe’s industrialization, it had far fewer universities per capita than peer nations on the continent. However, it had a well-developed system of apprenticeship which some scholars have theorized was the main means of human capital incubation and transmission during the Industrial Revolution. English cities with more apprenticeships during the 18th century tended to have a greater degree of labor force specialization in the mid-19th century. The final chapter examines the role of the land-grant college system, which was established in the mid-19th century in the United States. In addition to their primary role of providing postsecondary education to students, these institutions added a second channel for the creation of human capital: research to boost the productivity of the nation’s farms. American counties more firmly embedded within the land-grant college network tended to have a better-educated populace and a more specialized labor force; however, counties more exposed to land-grant colleges saw no improvements in agricultural productivity