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Use and Accuracy of the Diphenylamine Field Kit for Determining the Presence of Toxic Nitrate Levels in Forage Samples
Get PDFHigh-Resolution Igneous Stratigraphy of On- and Off-Axis Sills at a Nascent Spreading Center, Guaymas Basin, Gulf of California
No full textGuaymas Basin in the Gulf of California is a young spreading center with complex magmatic sill-sediment interactions, giving rise to interesting and complex chemical stratigraphy. X-ray fluorescence core scanning is employed here as a semiquantitative method of elemental analysis to shed light on magma differentiation and evolution using petrogenetically significant elements. An important aspect of this work is to demonstrate the successful application of elemental ratios to show compositional change with depth of sill, forming when magma is emplaced in wet sediments. Most significant are crystallization and alteration of minerals, leading to variation in maficity and trace element content.
The results on the igneous rock scans of off- and on-axis sills drilled by International Ocean Discovery Program (IODP) Expedition 385 and Deep-Sea Drilling Project (DSDP) Leg 64 show the complexity of the magma-sediment interaction in that region. The variations in elemental peak area ratios illustrate changes in magmatic composition, pointing to the presence of distinct magma batches that intruded over time across Guaymas Basin to form a system of sills with varying levels of magmatic evolution, particularly at an intricate off-axis hydrothermal mound structure called Ringvent (Sites U1547 and U1548) that reveals a stack of distinct intrusion bodies. They likely indicate two distinct generations of magmatic pulses. Further investigations of all IODP and DSDP sites that contain mafic hypabyssal rocks in the Guaymas Basin provided deeper insights into not only the geological interactions between wet sediment and sills but also the magmatic off- and on-axis architecture at an actively rifting sedimented spreading center, which is going to aid in further understanding of the magmatic structure by way of propagation mode and tectonic setting of this region
Al'Kalaeleth or The Account of The Creation of Aeleth
Get PDF���Al���Kalaeleth; or The Account of the Creation of Aeleth��� is a mythopoeic creative thesis that is inspired by mythic literature, cognitive research, and philosophy, though it also has supporting inspiration from genre fantasy and poetry. It is the story of how an unnamed prophet goes up a mountain with his father, returning forty days later to give an account of the creation of the world to his followers. The Prophet���s account is a frame narrative from which the highly symbolic creation myth can be explained and elaborated upon. While The Prophet and his father reveal the long-hidden truth about existence to their followers, two cities plot against him, watching his words and tallying his sins. ���Al���Kalaeleth��� is one chapter of what will be developed into a greater novel. The frame narrative therefore allows philosophical questions of cognitive philosophy and phenomenology to be approached. There is also an underlying meta-narrative that focuses on the plot as occurring within an authorial mind. The work and its research are guided by the research question: In what ways do the antiquarian structures of myth reveal greater understandings of psychological realities through symbolic rhetoric, especially when looking at beliefs in things such as religion and societal values? However, the work also is guided by the following secondary research questions: How do mythic and fantasy literature use the symbolic when discussing the literal creation of the world and the metaphysical development of the human psyche? What insights can these belief structures give into the modern perception of the human mind, and in what ways have these ancient beliefs impacted the ways that modern society understands psychology and cognitive philosophy? ���Al���Kalaeleth��� does not answer these secondary questions as it does the primary one, instead, as a work of art, it is meant to enable the audience to explore these questions from angles that are not commonly explored in the modern day, while also serving as an entertaining work of mythopoeic fantasy literature. ���Al���Kalaeleth��� is an innovative work of literature, both experimental in nature and founded in the mythopoeic tradition that was first tread by greats such as J.R.R. Tolkien, Lord Dunsany, and William Blake. The work was first presented at the English Undergraduate Research Honors Symposium that occurred on March 27th of 2024. When the complete novel is eventually published, ���Al���Kalaeleth��� is likely to have changed. However, the core ideas presented within the work are foundational to the entire novel. Even if the story changes, this piece should not be disregarded as simply a working draft or memento but as a piece of art in its own right
Assessment of Barely Visible Impact Damage in Composites Using Guided Waves and Image Classification
No full textThis work aims to establish a systematic approach for evaluating damage in composites, with a specific emphasis on assessing the severity of damage caused by low-velocity impacts. Low-velocity impacts give rise to barely visible damage, which includes localized matrix cracking and delamination within the composite material posing challenges while carrying out in-field service examinations on aerospace structures. Furthermore, the damage induced due to low-velocity im-pacts may increase in size with continued service operations, compromising the structure���s integrity. Identifying and assessing the severity of such damage, which is barely visible on the outer surface, remains a challenge with the current nondestructive evaluation techniques practiced in the industry. Structural health monitoring with guided waves (Lamb waves) has shown great potential for conducting in-field damage assessment in composite structures. The propagation of guided waves in composite materials is influenced by their anisotropic elastic properties as well as the damage type and severity involved.
The use of guided waves for damage identification has been a proven concept for a long time; however, extracting qualitative or quantitative information on the damage from the received wave signals is still a demanding process involving many obscurities caused by interactions of guided waves with damage. In fact, the complex patterns arising from guided waves as they pass through a damaged medium can present a unique opportunity if treated appropriately. An evaluation procedure to gauge the severity of damage in composite materials using the aforementioned patterns introduced in this study, following a detailed investigation of guided wave interaction with various damage mechanisms (i.e., transverse cracks, delamination, and a combination of both) that exist within composites. Additionally, the changes in the composition of guided wave signals acquired after their interaction with the aforementioned damage mechanisms are analyzed using advanced signal processing methods and are presented herein.
The two fundamental Lamb wave modes, i.e., symmetric S0 and anti-symmetric A0, co-exist and propagate at different speeds depending on the stiffness of the material media, excitation frequency, and thickness of the structure. When such a wave field is incident on discontinuities present in the host medium, redistribution of wave energy occurs, e.g., by scattering and mode conversion. The changes in the S0 and A0 modes are specific to the type of discontinuity, which is subjected to an independent analysis to study the effect of discontinuity on the behavior of the S0 and A0 modes. Building on the preceding understanding of lamb wave interaction with discontinuities, barely visible impact damage is examined, and metrics to evaluate the damage severity are proposed with exhaustive signal analysis.
The patterns observed in the guided wave signals upon encountering a specific damage type are treated as class-specific features in the current analysis. These patterns can be viewed as a digital fingerprint of damage and employed as an input for machine learning models to extract features for categorizing damage severity. The current work uses data sets generated for various realizations of damage via finite element models where parameters signifying different intensities of damage are varied. Then the digital features extracted from machine learning models are used first to identify the type of damage involved and subsequently categorize the recognized damage type into low, medium, and high damage classes based on the severity of the damage involved. This work successfully identifies the severity of damage when diverse damaged mechanisms are present, providing a methodology that can be adapted to assess damage during preliminary diagnostics and to make necessary repairs. The implications of this study hold significant potential for developing an automated system for damage assessment, facilitating quick in-field inspections
Characterizing Photon and Neutron Responses in CDMS Detectors Using Real and Simulated Cf-252 Data
No full textThe SuperCDMS collaboration is searching for dark matter via direct detection of WIMPs. We want to better understand how our detectors respond to both WIMP events and other interactions to help us analyze previously-taken data and also prepare for the next experiment. We focus on the Californium-252 calibration source used in the real experiment, as the neutrons it releases will produce signals similar to those caused by WIMPs; by comparing real Cf-252 data and data produced in our simulation framework, we can trace the physical processes that produce the features we see in the output of the detectors. We ���nd that the initial stages of the simulation are consistent with real Cf-252 behavior and have reasonable detector responses, but we also identify potential improvements to make simulations more realistic. Further, using simulations we identify several measurement complications that might be taken into account to improve analyses for real data
The Woman Thing: An Intersectional Exploration of Female Agency and Gender Performativity in Feminist Poetry
No full textFemininity is a concept that has long existed at the mercy of a fickle society. It is a word that is rigid in rules, yet malleable in definition, carefully contorting to fit whatever rhetoric society finds acceptable at a certain point in time and space. In examining the nuances of femininity, as well as the constant performance of gender, several topics are often called into question. For example, what does it mean to be a good wife? A good daughter? A successful woman? A ���real��� woman? A good woman. From the abstract concept of femininity itself to its implications for both agency and autonomy, the social construction of gender has, and continues to, inform significant elements of women���s day-to-day lives. While this is an argued reality, with words like ���feminism,��� ���feminist theory,��� and ���intersectionality��� often utilized as political buzzwords at the expense of their definitions, it is one that is both supported and informed by considerable scholarship, literature, and countless other artistic avenues. Therefore, the goal of this research is to examine the social construction and subsequent performativity of gender as it relates to femininity, female agency, autonomy, and domesticity. This will be achieved through an analysis of feminist literature and the completion of an original poetry collection, titled ���The Woman Thing. ���Utilizing these elements in both research and artistic inspiration, The Woman Thing will act as a critical analysis, not only of gender performativity as it relates to femininity, but also how it is informed by elements such as race, ethnicity, class, and sexual orientation
Instrumentation and Techniques for the Continuous Monitoring of Metabolites Using Surface-Enhanced Spatially-Offset Raman Spectroscopy
No full textIn order to transform the standard of medical care from reactionary to preventative-driven, the continuous monitoring of metabolites will play an increasingly important role in chronic disease management. While already the norm for the treatment of diabetes, continuous monitoring will be used to personalize the treatment of other chronic conditions as soon as the diagnostic sensors and tools are created. This work presents new tools and methods for the interrogation of implanted sensors using optical techniques with the potential for miniaturization to wearable form factors.
First, this work demonstrates continuous monitoring of dynamic pH and glucose in a simulated in vivo environment. Different types of hydrogels are evaluated for their ability to encapsulate the sensing chemistry and to measure the rate at which they allow the Surface-Enhanced Raman Spectroscopy (SERS) interaction between the target analyte and sensing chemistry to achieve steady-state, reversibly over repeated cycles.
Second, this work also demonstrates the design, build and test of a low-cost, standalone wearable Raman reader (WRR) prototype which is configurable to detect different targets. It has an adjustable offset that can be used for Spatially-Offset Raman Spectroscopy (SORS) which is helpful for in vivo sensing, as it enables optimizing the source-detector separation for scattering sources (e.g., implants) positioned at different depths. The WRR���s ability to perform the chemo-opto-electrical transduction of a target signal is compared to a commercial spectrometer when the biocompatible SERS-active hydrogel is at the surface, beneath a skin phantom and inside a cadaver.
Finally, this work makes improvements to published models and experimental setups to measure the signals of SERS-active hydrogels in tissue. These changes include reducing the target size to match the size of an implant, using a solid tissue barrier layer on top of the target rather than a stratified barrier and providing a base under the target to increase the traversable volume for the photons' random walk. Also, the model is extended to perform Raman scattering and to modify the optical properties after inelastic scattering occurs. Further, new processes display the spatial distributions of the emitted photons as they exit the tissue; this is helpful to determine the optimal offset for SORS.
In combination, these contributions advance the use of SORS as a continuous monitoring tool to repeatedly and reliably detect the SERS signals of a target in a range of environments as well as in a model. The WRR prototype presents all the components needed for in vivo sensing of configurable targets
Data for DALA
No full textA .csv file of the data dictionary for DALA (Database of African American and Predominantly White American Literature Anthologies), which compiles author information for generalist American and African American literature anthologies. This dataset is discussed in the book, "Digital Literary Redlining: African American Anthologies, Digital Humanities, and the Canon.
Enhancing the Hardware-Based Advanced Encryption Standard Implementation for Optimized Performance in Cyber-Physical Systems
No full textCyber-Physical Systems play a pivotal role in critical infrastructures but face distinct security challenges. Traditional software-based security measures often disregard to account for the resource limitations that these systems encounter. Field Programmable Gate Arrays offer a solution, enabling hardware-based cryptographic implementations to enhance security. This study delves into the design and analysis of optimized variants of cryptographic encryption implemented on hardware, shedding light on design methodologies and optimization techniques. Our research includes physical verification, rendering the encryption core readily applicable to be deployed in existing systems. Notably, this study goes beyond the existing research landscape, where the focus on specific metrics often neglects the holistic perspective. Our performance analysis, with a particular emphasis on throughput, undergoes rigorous scrutiny and provides a comprehensive view previously unexplored. This work significantly contributes to enhancing security by introducing efficient hardware-based cryptographic solutions and advancing the field with a comprehensive performance analysis