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Machine learning-assisted analyses for identification and prediction of genetic abnormalities in human pluripotent stem cell populations
No full textStem cells are the cells in our body with the unique ability to both self-renew and differentiate into specialized cell types, making them fundamental to growth, development, and tissue regeneration across our various systems. However, the behavior and essential functions of stem cells are influenced by a complex interplay of genetic and environmental factors. Aberrations in their gene expression profiles can lead to dysfunctional or diseased cells, potentially compromising tissue repair and regeneration. Given their promise in regenerative medicine for restoring damaged tissues and treating various conditions, accurately classifying stem cells to detect abnormalities is critical. Such classification ensures that only healthy, viable cells are utilized in therapeutic applications, preventing issues that could limit effectiveness or introduce complications in clinical practice of stem cell therapies.
One such method of classification is via machine learning, which is a transformative tool that allows researchers to process and interpret vast, complex datasets, including these stem cell gene expression profiles. By leveraging machine learning, researchers can uncover subtle patterns within these profiles that might otherwise go undetected, which offers deeper understandings of cell quality and differentiation potential. The machine learning models are able to analyze thousands of genes simultaneously, allowing them to identify key biomarkers and expression patterns that distinguish normal from abnormal stem cells. This capability is valuable for this classification task and the potential for future predictive modeling. Furthermore, machine learning allows for high-throughput analysis, making it possible to evaluate large numbers of stem cells quickly and with lesser bias and greater precision than manual analysis. This not only accelerates the research process but also supports scalable, reproducible insights into stem cell health, ultimately enhancing regenerative medicine approaches and the safe application of stem cell therapies.
After comparing Logistic Regression, Decision Tree, Random Forest, and Gradient Boosting models, we found that Random Forest delivered the most consistent and contextually appropriate results for this study. While Logistic Regression achieved the highest overall accuracy, both the Random Forest and Logistic Regression aligned identically with our key performance priorities: a low false negative rate and high recall for Class I. Although Random Forest tended to produce more false positives, this skew reflects a conservative approach – favoring the identification of abnormal stem cells, even at the risk of overcalling. In the context of stem cell therapy, this trade-off is desirable: a false negative could allow a harmful cell to slip through, while a false positive simply errs on the side of caution. Ultimately, Random Forest’s ability to capture complex, nonlinear relationships – something Logistic Regression inherently lacks – combined with its emphasis on minimizing false negatives, makes it the most suitable choice for our application
Fostering Economic Advancement Through Tourism Development in Dangriga, Belize
Get PDFThis paper discusses the relationship between economic development and the development of the tourism industry, based on a two-month project in Dangriga, Belize, which existed through collaboration of four University of Arkansas students, local community members and business owners, and organizational partners. This project explored sustainable tourism with the goal of benefiting the community\u27s continued economic advancement
Geochemical Analysis for Potential Critical Mineral Resources in Carbon Fly Ash
No full textThe growing demand for critical minerals, coupled with the increasing supply chain vulnerabilities, has intensified the need for alternative domestic resources of critical minerals beyond traditional mining. Many of these critical minerals are essential for advanced technologies, energy storage, and national security, yet the United States remains heavily dependent on foreign imports, particularly from China. This study evaluates the economic potential of critical mineral recovery from Carbon Fly Ash (CFA), a byproduct of coal combustion, to determine its viability as a secondary source of critical minerals. A geochemical and mineralogical assessment was conducted on CFA samples from various storage sites to analyze the concentration of 33 critical minerals. The study identified varying concentrations and economic potential, which are influenced by factors such as the type of coal burned and the scale of the CFA deposits. Results indicate that 24 of these critical minerals exhibit viable economic potential, suggesting that processing CFA for their recovery could offer high financial return while contributing to the strengthening of global infrastructure resilience. Given the growing urgency to reduce reliance on foreign suppliers, especially in light of recent trade restrictions and supply chain disruptions, developing domestic processing infrastructure for critical mineral recovery from CFA could provide a strategic advantage. Additionally, many of these high-value critical minerals co-occur or share similar extraction and processing methods, allowing for cost effective co-recovery. While challenges remain, including CFA heterogeneity and the need for large-scale processing capabilities, the findings of this study underscore the importance of investing in critical mineral recovery from CFA as a means to enhance resource security, strengthen economic resilience, and mitigate risk associated with geopolitical supply constraints
Comparison of RT-qPCR and RT-ddPCR on Assessing Model Virus in Wastewater
No full textThere is an increasing demand for quantifying viral loads in diverse wastewater systems using polymerase chain reaction (PCR). This study evaluates the performance of two commonly used workflows: reverse transcription quantitative PCR (RT-qPCR) and reverse transcription droplet digital PCR (RT-ddPCR) in wastewater. We compared the two methods by measuring the viral ribonucleic acid (RNA) of a model virus Phi6 in samples collected from various treatment stages at the Westside Wastewater Treatment Facility in Fayetteville, AR. RNA was extracted from real and synthetic wastewater samples and analyzed in parallel using both RT-qPCR and RT-ddPCR. Findings reveal that both methods demonstrated similar performance for detecting high and medium viral loads. However, RT-ddPCR showed significantly greater sensitivity for low viral loads, reliably detecting trace levels of viral particles where RT-qPCR struggled with detection. For direct viral detection without RNA extraction, RT-ddPCR\u27s performance was more impacted by water quality, whereas measurement on extracted samples demonstrated improved performance against inhibitors. Although RT-ddPCR entails higher costs and longer processing times, its superior sensitivity and resilience to sample contaminants, when used with RNA extraction, underscore its value for precise viral monitoring in wastewater applications
Consumer Acceptance of Gene-Edited Bananas: The Role of Cultural Cognition, Food Neophobia, and Perceived Safety
No full textBanana perishability leads to significant food waste, but gene editing has enabled the development of non-browning varieties that extend shelf life. This study examines consumer acceptance of gene-edited bananas in the Philippines, Japan, and China, focusing on cultural cognition, food neophobia, and perceived safety. Using a survey (n = 1,309), we analyze willingness to consume (WTC) and labeling preferences. Perceived safety was the strongest predictor of WTC: a one-unit increase raised the odds of WTC by 95.1% in the Philippines (β = 0.668, OR = 1.951, p \u3c 0.01), 171.2% in Japan (β = 0.998, OR = 2.712, p \u3c 0.01), and 267.4% in China (β = 1.301, OR = 3.674, p \u3c 0.01). Food neophobia significantly reduced WTC across all countries (ORs = 0.541–0.580; p \u3c 0.01). Cultural worldview significantly influenced WTC in the Philippines (β = -0.264, OR = 0.768, p \u3c 0.01) and shaped labeling preferences in Japan. Environmental messaging increased WTC in Japan (β = 0.568, OR = 1.765, p \u3c 0.05) but reduced it in China (β = -0.610, OR = 0.543, p \u3c 0.05). These findings emphasize the role of perceived safety, information framing, and cultural context in shaping consumer attitudes toward emerging food technologies
The Utilization and Deterioration of Travertine in Classical, Baroque, and Fascist Architecture: A Case Study from Rome, Italy
Get PDFTravertine limestone has formed the resilient backbone of Roman architecture for over two millennia and across several cultural periods. This study identified the leading causes of travertine decay in Rome across Ancient, Baroque, and Fascist periods in order to efficiently prioritize conservation and restoration efforts across the city. The methodology developed here can then be utilized in other urban settings. Rome’s iconic landmarks such as the Flavian Amphitheater, St. Peter’s Basilica, and the Spanish Steps all owe their existence to this local limestone. High rates of urbanization now dictate how architectural travertine interacts with its surrounding environments and landscapes. Grand avenues oriented in the same cardinal directions as the prevailing, seasonal winds have been found to exacerbate mechanical and chemical weathering and erosion of this calcareous building and cladding material. Conversely, narrow medieval and baroque streets hinder sunlight access and increase shadowfall – facilitating the growth of biodeteriorators such as cyanobacteria and lichens. Increased vehicle ownership and public transportation produces abundant exhaust fumes that bind to travertine producing an unsightly black crust called scialbatura.
This research analyzed how environmental factors and driving agents interacted and affected travertine deterioration by employing nondestructive field methods, thematic cartography, and geographical information systems (GIS) to identify sites most likely to have the highest rates of weathering, recession, and erosion. No single parameter was solely responsible, but rather the relationships between an increased surface porosity (a leading factor), prevailing winds, urbanization, and cultural norms were evident within this vital project
Synthesis and X-ray Characterization of Nickel Phosphide Nanostructures for Water Oxidation
No full textThe pursuit of earth-abundant 3d transition metal catalysts for alkaline water electrolysis remains an active area of research. While NiFe layered double hydroxides (LDH) are currently the most active catalysts for the oxygen evolution reaction (OER), doping Ni-based catalysts with phosphorus to form Ni metal phosphides has emerged as a promising alternative. However, the complex crystalline and amorphous phases of NiPx have hindered their characterization, and the OER mechanism and origin of activity remain unclear. This dissertation aims to elucidate the synthesis, OER performance, and in situ reconstruction of amorphous NiPx-based nanomaterials, with a focus on in situ and ex situ X-ray characterization. Through a systematic investigation, we developed a synthetic route for uniform amorphous Ni70P30 nanoparticles, which served as a template for the formation of phase-pure Ni12P5, Ni2P, and Ni5P4 via temperature modulation. Using in situ X-ray absorption spectroscopy (XAS), we monitored the transformation of α-Ni(OH)2 and β-Ni(OH)2 during OER, revealing that β-Ni(OH)2 undergoes a potential-induced intercalation of anions to form a mixed α/β Ni(OH)2 phase. We also investigated amorphous NiPx with an oxidized α-Ni(OH)2 shell during OER, finding that the α-Ni(OH)2 shell protects the conductive NiPx core from structural reconstruction defects, promoting high OER performance. Furthermore, our study demonstrated that the NiPx-α-Ni(OH)2 core-shell nanoparticle promotes shorter Ni-O bonds at high anodic potentials, enhancing OER activity. We also developed a facile method for incorporating Fe and Co into amorphous Ni70P30 nanoparticles, resulting in uniform alloy and core-shell structures with improved OER activity. Notably, the addition of Co altered the OER mechanism, promoting lattice oxygen activation over the adsorbate evolution mechanism, although it was limited by irreversible inactivation of Co(IV) activation sites. This dissertation provides a fundamental understanding of synthesizing and monitoring OER activities of amorphous Ni-based phosphides, shedding light on their complex structure-activity relationships. The findings of this study have significant implications for the development of efficient and earth-abundant catalysts for alkaline water electrolysis
Analog Low Dropout Regulator Design Within a 12nm FinFET Node
Get PDFModern ICs require the use of multiple voltage regulators to regulate power, this creates the need for analog low dropout regulator (LDO) designs in more advanced nodes such as for the 12nm FinFET process. Analog design is particularly challenging in FinFET processes due to a variety of factors, such as quantized parameters, large parasitic values and length of diffusion effects. An analog LDO was chosen for its improved power supply rejection ratio (PSRR) over digital and hybrid approach which is a key metric for voltage sensitive applications. The LDO was designed through an iterative approach to address the difficulty of designing analog devices in a FinFET node. The LDO has a good post layout line regulation of 0.57%/V, however a post layout has a load regulation of 4.9%/A. The LDO achieved a PSRR of -43dB at 100kHz and a noise value of 103 nV/√Hz at a current draw of 50mA and a layout size of 0.007225mm2. The PSRR is significantly better than comparable works that use a digital or hybrid LDO approach. The circuit had an overshoot value of 15mV, and a voltage undershoot value of 10mV when switching current by 100mA. In addition, the circuit was tested underneath multiple corners that would be used for automotive qualification from SS -40C to FF 125C with 13 corners total tested. The design was iterated to meet specifications on all corners. There are issues with the PSRR values and overshoot values at the SS -40C corner that are discussed. Potential fabrication of the circuit is also discussed
An Analytical Evaluation of Economic Geography within Maine and its Resource Industries: 1600 to present
Get PDFResource peripheries represent a fringe area within economic geography, originating from the core-periphery theory developed by Friedmann and Miller. This concept has evolved to address global and regional contexts, referring to marginalized regions that rely heavily on the extraction and export of natural resources. By studying these regions, we gain a deeper understanding of critical components in global economic systems. This dissertation focuses on Maine as a case study of a resource periphery, using the framework proposed by Hayter et al. (2003) within the broader regional contexts of New England and the United States. Key factors explored include resource exploitation, boom-and-bust cycles, and economic policy and management. This study analyzes Maine\u27s history and industries through the lens of its resource sectors, employing both qualitative and quantitative methods, particularly due to the limited availability of numerical data before the mid-20th century. Maine, as a resource periphery within the U.S., has historically relied on timber and seafood, the dominant sectors of its economy. This research assesses how Maine’s fishing and forestry industries have shaped its identity and economic development and determines if the state falls within the framework of a resource periphery. Additionally, this dissertation expands on the discourse of “close peripheries”, examining a resource periphery that exists within the sub-national level
Trouble Don\u27t Last Always
Get PDFBeing born and raised in the South, it has become clear to me that acts of adornment and cultural representations of home are a prevalent factor of the Southern archive. Trouble don’t last always considers the various elements of coloniality that saturate function within the Southern Black home, noting that acts of adornment and cultural representations of home are a prevalent factor of the Southern archive. Enumerating the various roles that Black women play as place makers while also navigating elements of coloniality. In turn these spaces do not function without their knowledge production. This knowledge is one that becomes generational and is inherited through actions of their foremothers. and I am in great debt to mine. I’ll be humming hymns of your love and kindness forever