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Articles 91 - 120 of 2433

Full-Text Articles in Physical Sciences and Mathematics

The Bactericidal Activity Of A Novel Aneurinibacillus Aneurinilyticus Isolate Effectively Controls Foodborne Pathogens Campylobacter Jejuni And Listeria Monocytogenes, Peter M. Rubinelli, Rohana Liyanage, Jackson Lay, Jennifer C. Acuff Sep 2023

The Bactericidal Activity Of A Novel Aneurinibacillus Aneurinilyticus Isolate Effectively Controls Foodborne Pathogens Campylobacter Jejuni And Listeria Monocytogenes, Peter M. Rubinelli, Rohana Liyanage, Jackson Lay, Jennifer C. Acuff

Chemistry & Biochemistry Faculty Publications and Presentations

Human zoonotic infection with Campylobacter is a major cause of gastroenteritis in the United States and worldwide. Listeria monocytogenes causes a potentially fatal infection in humans and is often attributed to contaminated food. Genetic typing has demonstrated that Campylobacter infection is often associated with the consumption of contaminated poultry products, with Campylobacter often colonizing the poultry gastrointestinal tract, while listeriosis is commonly associated with the consumption of contaminated ready-to-eat (RTE) foods. In this study, a strain of endospore-forming bacterium (strain NH) that is bactericidal towards the human food pathogens Campylobacter jejuni and Listeria monocytogenes was identified and characterized. Transwell experiments …

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Carbon Isotope Chemostratigraphy, Geochemistry, And Biostratigraphy Of The Paleocene–Eocene Thermal Maximum, Deepwater Wilcox Group, Gulf Of Mexico (Usa), Glenn R. Sharman, Eugene Szymanski, Rebecca A. Hackworth, Alicia C.M. Kahn, Lawrence A. Febo, Jordan Oefinger, Gunnar M. Gregory Sep 2023

Carbon Isotope Chemostratigraphy, Geochemistry, And Biostratigraphy Of The Paleocene–Eocene Thermal Maximum, Deepwater Wilcox Group, Gulf Of Mexico (Usa), Glenn R. Sharman, Eugene Szymanski, Rebecca A. Hackworth, Alicia C.M. Kahn, Lawrence A. Febo, Jordan Oefinger, Gunnar M. Gregory

Geosciences Faculty Publications and Presentations

The Paleocene–Eocene Thermal Maximum (PETM) represents the most pronounced hyperthermal of the Cenozoic era and is hypothesized to have resulted in an intensification of the paleohydrologic cycle, including enhanced seasonality and increased sediment discharge to the coastal ocean. Although the PETM has been widely documented, there are few records from deposits that form the distal, deepwater components of large sediment-routing systems. This study presents new constraints on the stratigraphic placement of the PETM in the deepwater Gulf of Mexico basin through analysis of geochemical, carbon isotopic, and biostratigraphic data within a ∼124 m cored interval of the Wilcox Group. Biostratigraphic …

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Guar-Based Injectable Hydrogel For Drug Delivery And In Vitro Bone Cell Growth, Humandra Poudel, Ambar R. Rangumagar, Pooja Singh, Adeolu Oluremi, Nawab Ali, Fumiya Watanabe, Joseph Batta-Mpouma, Jin-Woo Kim, Ahona Ghosh, Anindya Ghosh Sep 2023

Guar-Based Injectable Hydrogel For Drug Delivery And In Vitro Bone Cell Growth, Humandra Poudel, Ambar R. Rangumagar, Pooja Singh, Adeolu Oluremi, Nawab Ali, Fumiya Watanabe, Joseph Batta-Mpouma, Jin-Woo Kim, Ahona Ghosh, Anindya Ghosh

Chemistry & Biochemistry Faculty Publications and Presentations

Injectable hydrogels offer numerous advantages in various areas, which include tissue engineering and drug delivery because of their unique properties such as tunability, excellent carrier properties, and biocompatibility. These hydrogels can be administered with minimal invasiveness. In this study, we synthesized an injectable hydrogel by rehydrating lyophilized mixtures of guar adamantane (Guar-ADI) and poly-β-cyclodextrin (p-βCD) in a solution of phosphate-buffered saline (PBS) maintained at pH 7.4. The hydrogel was formed via host-guest interaction between modified guar (Guar-ADI), obtained by reacting guar gum with 1-adamantyl isocyanate (ADI) and p-βCD. Comprehensive characterization of all synthesized materials, including the hydrogel, was performed using …

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Alkaline Pretreatment And Air Mixing For Improvement Of Methane Production From Anaerobic Co-Digestion Of Poultry Litter With Wheat Straw, Yuanhang Zhan, Jun Zhu, Yiting Xiao, Leland C. Schrader Sep 2023

Alkaline Pretreatment And Air Mixing For Improvement Of Methane Production From Anaerobic Co-Digestion Of Poultry Litter With Wheat Straw, Yuanhang Zhan, Jun Zhu, Yiting Xiao, Leland C. Schrader

Biological and Agricultural Engineering Faculty Publications and Presentations

Alkaline pretreatment (AL) and air mixing (air) both have the potential to improve anaerobic co-digestion (Co-AD) of poultry litter with wheat straw for methane production. In this study, the effects of the combination of AL (pH 12 for 12 h) and air mixing (12 mL·d−1) on the Co-AD process were investigated. The substrate hydrolysis was enhanced by AL, with soluble chemical oxygen demand increased by 4.59 times and volatile fatty acids increased by 5.04 times. The cumulative methane yield in the group of Co-AD by AL integrated with air (Co-(AL + air)), being 287 mL·(g VSadded) …

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Estimation Of Gross Primary Productivity Of Rice In Arkansas Using The Vegetation Photosynthesis Model, Riasad Bin Mahbub Aug 2023

Estimation Of Gross Primary Productivity Of Rice In Arkansas Using The Vegetation Photosynthesis Model, Riasad Bin Mahbub

Graduate Theses and Dissertations

An estimate of the gross primary productivity (GPP) of rice fields can be instrumental to understand their harvest yield and to fulfill an array of agricultural monitoring needs. One of the most common satellite-based models to estimate GPP is the vegetation photosynthesis model (VPM). In this study, we use the VPM model for rice cropland in Arkansas and validate our findings against 16 site-years in-situ data (eddy covariance (EC)). At the site scale, results validated against 16 site-years have shown that the VPM with site information (R2 = 0.71, MAE = 2.90 g C m-2day- 1, and RMSE = 4.04 …

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Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino Aug 2023

Studying The Stability Of Collagen/Heparin Coatings To Be Used In Cell Therapy Applications, Gavin Mussino

Biological Sciences Undergraduate Honors Theses

This honors thesis aims to investigate the reusability and performance of cell coatings for cell therapy applications. Cell therapy, which involves the use of human cells to repair or replace damaged tissues, holds immense potential for medical advancements. However, ensuring the survival and functionality of transplanted cells remains a significant challenge. We focused on studying the effectiveness of coatings applied to cells for improved cell growth and viability. The research project involved the preparation of the coatings using a layer-by-layer method and the subsequent seeding of cells. The coated cells were then subjected to a series of experiments to assess …

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Simulation And Analysis Of Self-Assembling Slat-Based Dna Ribbons, Lukas Vaughan, Hunter J. Fleming Aug 2023

Simulation And Analysis Of Self-Assembling Slat-Based Dna Ribbons, Lukas Vaughan, Hunter J. Fleming

Computer Science and Computer Engineering Undergraduate Honors Theses

Though still in its infancy, the design of DNA crisscross slats presents great potential in the algorithmic self-assembly of DNA. The provision for higher levels of cooperativity allows for fewer errors through the natural proofreading of slat placement, leading to more robust assembly. Highly accurate simulations of self-assembling DNA squares have been achieved by following the kinetic Tile Assembly Model. Building on that foundation, this study seeks to calibrate the system parameters of a kinetic simulator for self-assembling DNA slats to match experimental results and to use those ranges of parameters to perform exploratory simulations of systems not yet tested …

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Multi-Object Tracking: A Computer Vision Paradigm, Natalie Friede Aug 2023

Multi-Object Tracking: A Computer Vision Paradigm, Natalie Friede

Computer Science and Computer Engineering Undergraduate Honors Theses

This paper delves into advancements and hurdles encountered in multi-object tracking, a critical aspect of computer vision, with a special emphasis on 'referring understanding.' This technique integrates natural language queries into multi-object tracking tasks, thus broadening the scope for practical applications. The innovative referring multi-object tracking (RMOT) approach emerges as a promising solution in this regard. The effectiveness of RMOT was tested using the Refer-KITTI dataset, a dataset specializing in traffic scenes. The evaluation revealed RMOT's ability to handle a diverse range of referent objects, its robust temporal dynamics, and a high level of adaptability. While the paper acknowledges the …

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Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed Aug 2023

Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed

Graduate Theses and Dissertations

This dissertation explores the application of remote sensing technologies in conservation agriculture, specifically focusing on identifying and mapping winter cover crops and assessing voluntary cover crop adoption and cropping patterns in the Arkansas portion of the Mississippi Alluvial Plain (MAP). In the first chapter, a systematic review using the PRISMA methodology examines the last 30 years of thematic research, development, and trends in remote sensing applied to conservation agriculture from a global perspective. The review uncovers a growing interest in remote sensing-based research in conservation agriculture and emphasizes the necessity for further studies dedicated to conservation practices. Among the 68 …

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Evaluation Of Biochar Rate And Hemp Cultivar For The Phytoremediation Of Heavy-Metal-Contaminated Soil From The Tar Creek Superfund Site, Dietrich Thurston Aug 2023

Evaluation Of Biochar Rate And Hemp Cultivar For The Phytoremediation Of Heavy-Metal-Contaminated Soil From The Tar Creek Superfund Site, Dietrich Thurston

Graduate Theses and Dissertations

Soil contamination by cadmium (Cd), lead (Pb), and zinc (Zn) at the Tar Creek Superfund site in Northeast Oklahoma remains a threat to the environment and local ecosystem. Phytoremediation by industrial hemp (Cannabis sativa L.) and the use of biochar (BC) have been independently shown to be effective methods to remediate heavy-metal-contaminated soils. The objective of this greenhouse study was to evaluate the effects of industrial hemp cultivar (‘Carmagnola’ and ‘Jinma’), BC rate (0, 2, 5, and 10% by volume), soil contamination level (low, medium, and high), and their interactions on above- and belowground (AG and BG, respectively) plant dry …

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Constraining High Temperature Deformation And Metamorphism In The Southern Wet Mountains, Colorado, Usa: Implications For The Regional Extent Of The Picuris Orogeny, Sarah Morse Aug 2023

Constraining High Temperature Deformation And Metamorphism In The Southern Wet Mountains, Colorado, Usa: Implications For The Regional Extent Of The Picuris Orogeny, Sarah Morse

Graduate Theses and Dissertations

The Wet Mountains of Colorado are underlain by exhumed Proterozoic metamorphic rock that lies north of the recently identified 1.46 to 1.40 Ga Picuris orogen in northern New Mexico. The Picuris orogen is inferred to have formed in response to a Mesoproterozoic (ca. 1.49-1.40 Ga) contractional to transpressional event extrapolated to be regional in extent. It has been proposed that the Picuris orogen composes the westernmost tectonic segment of the Pinware-Baraboo-Picuris orogen that formed along an evolving convergent margin that becomes younger from northeast to southwest. This study is focused on the record of high temperature deformation, metamorphism, and plutonism …

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Comparing Predictive Performance Of Garch And Stochastic Volatility Models, Swapnaneel Nath Aug 2023

Comparing Predictive Performance Of Garch And Stochastic Volatility Models, Swapnaneel Nath

Graduate Theses and Dissertations

This paper compares the predictive performance of two commonly used financial models, the Generalized Auto-Regressive Conditional Heteroskedasticity (GARCH) model, and the Stochastic Volatility model. Both techniques are used in the finance literature to model returns on an asset; the main difference between the two is that the former holds volatility as deterministic, whereas the latter treats it as a stochastic component. Three 10-year periods (2006-15, 2008-17, and 2010-19) of returns of the S&P-500 Index are used to train the two models. The parameter estimation is done using Hamiltonian Monte Carlo. Then, using Sequential Monte Carlo updates, returns for 2016, 2018, …

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Investigation Of The Flow Field In The Jack Rabbit Ii Mock Urban Environment Field Tests Using A 1:50 Scale Wind Tunnel Model, Paulo Victor De Freitas Lopes Aug 2023

Investigation Of The Flow Field In The Jack Rabbit Ii Mock Urban Environment Field Tests Using A 1:50 Scale Wind Tunnel Model, Paulo Victor De Freitas Lopes

Graduate Theses and Dissertations

Accidental release of toxic chemicals can put workers and nearby populations at significant risk. Consequence assessment of accidents in urban environments is of particular interest. Urban geometries create wind channels between buildings, along with particularly dangerous areas downwind of buildings, where near-stagnant flow is present. Furthermore, recirculation zones can be formed between buildings, trapping high concentrations of toxic gases at ground level, particularly for denser-than-air gases. In 2015, the Department of Homeland Security conducted the Jack Rabbit II Field Test (JR-II) at Dugway Proving Ground, UT. During JR-II, chlorine was released at the center of a Mock Urban Environment (MUE) …

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Verification Of Astm Centrifugation Equations For Soil Suction Determination, Esteban Maclein Miranda Pinzon Aug 2023

Verification Of Astm Centrifugation Equations For Soil Suction Determination, Esteban Maclein Miranda Pinzon

Graduate Theses and Dissertations

The unit correction constant (B) in the ASTM D6836 standard needs to be evaluated. The B-value was proposed to be 0.00548 instead of 0.00553. This apparent discrepancy led to an investigation comparing the predicted and measured suction values for high air entry (HAE) ceramic disks. A Beckman-Coulter Model J6-MI six-bay centrifuge and a WP4C Dewpoint Potentiameter were used in the testing program. HAE ceramic disks rated with bubbling pressures of 3-bar and 5-bar were used as analogue soil specimens. The HAE ceramic disks were spun in the small-scale centrifuge to apply prescribed suction amounts and then placed in the WP4C …

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Runoff Water Quality And Crop Growth As Affected By Wastewater-Derived Struvite, Machaela Morrison Aug 2023

Runoff Water Quality And Crop Growth As Affected By Wastewater-Derived Struvite, Machaela Morrison

Graduate Theses and Dissertations

Mined phosphate rock, used to produce phosphorus (P) fertilizers, is a finite resource. Struvite (MgNH4PO4 • 6H2O) that has been synthetically produced from a stock solution of known P and nitrogen (N) concentrations has been shown to be an effective, alternative fertilizer-P source for various crops. However, little is known about the runoff-water-quality implications from and the crop response to soil application of struvite created from an actual municipal wastewater source. This study consisted of two objectives: i) to evaluate the effects of soil [i.e., Creldon (Oxyaquic Fragiudalf), Dapue (Fluventic Hapludoll), Roxana (Typic Udifluvent), and Calloway (Aquic Fraglossudalf) series], fertilizer-P …

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Circuitry And Semiconductor Studies For Making A Graphene Energy Harvesting Device, Ferdinand Harerimana Aug 2023

Circuitry And Semiconductor Studies For Making A Graphene Energy Harvesting Device, Ferdinand Harerimana

Graduate Theses and Dissertations

Freestanding graphene has constantly moving ripples. Due to its extreme flexibility, graphene responds to ambient vibrations and changes its curvature from concave to convex and vice versa. During a ripple inversion 10,000 atoms move together, suggesting the presence of kinetic energy which can be harvested. In this study we present circuitry and semiconductor studies for harvesting energy from graphene vibrations. The goal of the study is to develop a graphene energy harvesting chip which can serve as a battery replacement in low power electronics. In the first study we determined the best circuit for harvesting vibrational low power. To do …

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Poly(Ionic Liquid)S For Magnetic, Ionic, And Electrical Stimuli-Responsive Applications, Kayla Ann Foley Aug 2023

Poly(Ionic Liquid)S For Magnetic, Ionic, And Electrical Stimuli-Responsive Applications, Kayla Ann Foley

Graduate Theses and Dissertations

Poly(ionic liquid)s (PILs) are a fascinating subclass of strong polyelectrolytes formed from polymerizable ionic liquids. As a result of their unique properties and counterion exchangeability, PILs can exhibit conformation structure or material property changes in response to external stimuli such as changes in pH/ionic environment, magnetic fields, and electric potentials. In Chapter 1, a comprehensive review of PILs design as well as their stimuli-responsive behavior is provided. Additional motivation for each dissertation chapter is also discussed. In Chapter 2, magnetically responsive PILs (MPILs) are developed from complexing paramagnetic salts with a random PIL copolymer containing a metal-coordinating co-monomer, acrylamide. A …

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Photon Counting Statistics Of Classical And Quantum Light Sources, Luis Felipe Morales Bultron Aug 2023

Photon Counting Statistics Of Classical And Quantum Light Sources, Luis Felipe Morales Bultron

Graduate Theses and Dissertations

Multiple sources of light, including coherent light, thermal light, light from a degenerate parametric oscillation and resonance fluorescence from a two level coherently driven atom are considered for the analysis of their wait time statistics. We include the second order normalized correlation function and Mandel's Q parameter for brief discussion. A general framework to analyze the generalized conditional and unconditional wait time distributions is also obtained in order to understand the photo-count statistics of the light sources included in this work. Average and variance of wait times with respect to both unconditional and conditional wait time distribution are also obtained …

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A Comparative Study Of Techniques For Non-Monotonic Dependence With Emphasis On Sensitivity To Sample Size, Noise Level And Computational Attributes, Fariha Tasnim Aug 2023

A Comparative Study Of Techniques For Non-Monotonic Dependence With Emphasis On Sensitivity To Sample Size, Noise Level And Computational Attributes, Fariha Tasnim

Graduate Theses and Dissertations

Evaluating association between variables is often of interest by many researchers. To serve this purpose, different association measures have been developed. However, type of relation between variables affects the degree of relationship. Hence, detection of the rela- tionship between variables is germane to measuring the correlation coefficient. With that mindset, here we explored six non-monotonic measure of association techniques and com- pared them with three classical approaches. Due to inconsistency in definition and range of different techniques, it is not feasible to compare the correlation estimates as their nature of variability differ. Therefore, we used permutation test based on Monte …

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Chemostratigraphic And Paleoclimatic Studies Of Cloverly Formation, Northern Wyoming, U.S.A, Queen Amarachi Kalu Aug 2023

Chemostratigraphic And Paleoclimatic Studies Of Cloverly Formation, Northern Wyoming, U.S.A, Queen Amarachi Kalu

Graduate Theses and Dissertations

The Early – Late Cretaceous transition in Western North America recorded a period of rapid climatic and tectonic change in Earth’s history. Major climate events associated with large igneous province eruptions caused several instances of ocean anoxic events (OAE) and perturbations to the global carbon (C) – cycle. These perturbations to the global C-cycle are observed in the bulk organic C record of both marine and terrestrial deposits and can be used to correlate units across major depositional basins. Major efforts are being made to generate time-constrained palaeontologic and paleoclimate information from the North American Cordilleran foreland basin and C-isotope …

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Etching Of Silicon Wafer In Preparation Of Graphene Transfer, Floyd T. Lancaster Iii Aug 2023

Etching Of Silicon Wafer In Preparation Of Graphene Transfer, Floyd T. Lancaster Iii

Graduate Theses and Dissertations

Following the research done on graphene looking at its unique properties it has been found that graphene can be used as a varying capacitor. What has been observed is that graphene acts almost like a torrential ocean constantly fluctuating. What we use is a silicon wafer with multiple etched layers to create a stable platform on which to capture this energy. In this paper we will discuss the general setup and step-by-step procedures required to create a functioning variable capacitor out of graphene, gold, and Silicon dioxide (SiO2) substrate. Electron Beam Lithography (EBL) is used to create the initial design …

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Towards Multi-Modal Explainable Video Understanding, Kashu Yamazaki Aug 2023

Towards Multi-Modal Explainable Video Understanding, Kashu Yamazaki

Graduate Theses and Dissertations

This thesis presents a novel approach to video understanding by emulating human perceptual processes and creating an explainable and coherent storytelling representation of video content. Central to this approach is the development of a Visual-Linguistic (VL) feature for an interpretable video representation and the creation of a Transformer-in-Transformer (TinT) decoder for modeling intra- and inter-event coherence in a video. Drawing inspiration from the way humans comprehend scenes by breaking them down into visual and non-visual components, the proposed VL feature models a scene through three distinct modalities. These include: (i) a global visual environment, providing a broad contextual understanding of …

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Cultural Competence Among Child Life Professionals, Rachel Burger Aug 2023

Cultural Competence Among Child Life Professionals, Rachel Burger

Graduate Theses and Dissertations

There is an ever-growing need for individuals to work towards cultural competence, especially when those individuals work in healthcare. As healthcare professionals with backgrounds in child development and who provide emotional and psychological support to diverse pediatric patient populations in a variety of different sectors, child life specialists (CLS) and Certified Child Life Specialists (CCLSs) have an even greater need for understanding cultural competence (Thompson, 2009). The purpose of the current study was to examine the cultural competency levels of CCLSs, the type of cultural competence professional development units (PDUs) they participate in, and their perspectives on cultural competence in …

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Dual Ni/Co-Hemin Metal-Organic Framework-Prgo For High-Performance Asymmetric Hybrid Supercapacitor, Kimia Zarean Mousaabadi, Ali A. Ensafi, Erfan Naghsh, Jin-Song Hu, Behzad Rezaei Aug 2023

Dual Ni/Co-Hemin Metal-Organic Framework-Prgo For High-Performance Asymmetric Hybrid Supercapacitor, Kimia Zarean Mousaabadi, Ali A. Ensafi, Erfan Naghsh, Jin-Song Hu, Behzad Rezaei

Chemistry & Biochemistry Faculty Publications and Presentations

In this study, we conducted direct synthesis of a dual metal–organic framework (Ni/Co-Hemin MOF) on phosphorous-doped reduced graphene oxide (PrGO) to serve as an active material in high-performance asymmetrical supercapacitors. The nanocomposite was utilized as an active material in supercapacitors, exhibiting a noteworthy specific capacitance of 963 C g−1 at 1.0 A g−1, along with a high rate capability of 68.3% upon increasing the current density by 20 times, and superior cycling stability. Our comprehensive characterization and control experiments indicated that the improved performance can be attributed to the combined effect of the dual MOF and the …

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Englacial Drainage Drives Positive Feedback Depression Growth On The Debris-Covered Ngozumpa Glacier, Nepal, R. M. Strickland, M. D. Covington, J. D. Gulley, R. B. Kayastha, J. M. Blackstock Aug 2023

Englacial Drainage Drives Positive Feedback Depression Growth On The Debris-Covered Ngozumpa Glacier, Nepal, R. M. Strickland, M. D. Covington, J. D. Gulley, R. B. Kayastha, J. M. Blackstock

Geosciences Faculty Publications and Presentations

The development of hummocky topography is a poorly understood aspect of down-wasting on debris-covered glaciers that is often attributed to variable debris thickness. Thousands of enclosed depressions pit the hummocky topography. To better understand depression growth, we examined the size distribution and geometry of depressions on the Ngozumpa Glacier, in the Everest Region of Nepal. The depressions exhibited a power-law size distribution, fractal perimeters, and power-law depth-area scaling, which suggest positive feedback growth. With a simple model, we showed that positive feedback growth produces similar power-law size distributions. Based on these findings, we propose a “sinkhole” hypothesis for the development …

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Interpolation Problems And The Characterization Of The Hilbert Function, Bryant Xie Jul 2023

Interpolation Problems And The Characterization Of The Hilbert Function, Bryant Xie

Mathematical Sciences Undergraduate Honors Theses

In mathematics, it is often useful to approximate the values of functions that are either too awkward and difficult to evaluate or not readily differentiable or integrable. To approximate its values, we attempt to replace such functions with more well-behaving examples such as polynomials or trigonometric functions. Over the algebraically closed field C, a polynomial passing through r distinct points with multiplicities m1, ..., mr on the affine complex line in one variable is determined by its zeros and the vanishing conditions up to its mi − 1 derivative for each point. A natural question would then be to consider …

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Hurricane Impacts On Land In The Central And Eastern Caribbean Since 1494 Ce From Written Records, Michael Chenoweth, Ian Howard Jul 2023

Hurricane Impacts On Land In The Central And Eastern Caribbean Since 1494 Ce From Written Records, Michael Chenoweth, Ian Howard

Geosciences Faculty Publications and Presentations

Written accounts of hurricanes and their impacts in the Caribbean region date back to 1494 CE We report a new compilation of hurricanes in the longest settled regions of the central and eastern Caribbean region (CECR) that is the most complete yet produced and present basic statistics. We assess likely undercounts of hurricanes due to incomplete documentary records in the earliest part of the record by using the most complete reporting from Puerto Rico relative to the remainder of the CECR. We compare our results with other documentary and proxy data from the region and demonstrate using wavelet analysis significant …

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The Appropriateness Of Outlier Exclusion Approaches Depends On The Expected Contamination: Commentary On André (2022), Daniel Villanova Jul 2023

The Appropriateness Of Outlier Exclusion Approaches Depends On The Expected Contamination: Commentary On André (2022), Daniel Villanova

Marketing Faculty Publications and Presentations

In a recent article, André (2022) addressed the decision to exclude outliers using a threshold across conditions or within conditions and offered a clear recommendation to avoid within-conditions exclusions because of the possibility for large false-positive inflation. In this commentary, I note that André’s simulations did not include the situation for which within-conditions exclusion has previously been recommended—when across-conditions exclusion would exacerbate selection bias. Examining test performance in this situation confirms the recommendation for within-conditions exclusion in such a circumstance. Critically, the suitability of exclusion criteria must be considered in relationship to assumptions about data-generating mechanisms.

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Freestanding Graphene Heat Engine Analyzed Using Stochastic Thermodynamics, J. Durbin, J. M. Mangum, M. N. Gikunda, F. Harerimana, P. Kumar, L. L. Bonilla, P. M. Thibado Jul 2023

Freestanding Graphene Heat Engine Analyzed Using Stochastic Thermodynamics, J. Durbin, J. M. Mangum, M. N. Gikunda, F. Harerimana, P. Kumar, L. L. Bonilla, P. M. Thibado

Physics Faculty Publications and Presentations

We present an Ito-Langevin model for freestanding graphene connected to an electrical circuit. The graphene is treated as a Brownian particle in a double-well potential and is adjacent to a fixed electrode to form a variable capacitor. The capacitor is connected in series with a battery and a load resistor. The capacitor and resistor are given separate thermal reservoirs. We have solved the coupled Ito-Langevin equations for a broad range of temperature differences between the two reservoirs. Using ensemble averages, we report the rate of change in energy, heat, and work using stochastic thermodynamics. When the resistor is held at …

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Forecasting Sea Level Rise-Driven Inundation In Diked And Tidally Restricted Coastal Lowlands, K. M. Befus, A. P.D. Kurnizki, K. D. Kroeger, M. J. Eagle, T. P. Smith Jul 2023

Forecasting Sea Level Rise-Driven Inundation In Diked And Tidally Restricted Coastal Lowlands, K. M. Befus, A. P.D. Kurnizki, K. D. Kroeger, M. J. Eagle, T. P. Smith

Geosciences Faculty Publications and Presentations

Diked and drained coastal lowlands rely on hydraulic and protective infrastructure that may not function as designed in areas with relative sea-level rise. The slow and incremental loss of the hydraulic conditions required for a well-drained system make it difficult to identify if and when the flow structures no longer discharge enough water, especially in tidal settings where two-way flows occur through the dike. We developed and applied a hydraulic mass-balance model to quantify how water levels in the diked and tidally restricted coastal wetlands and water bodies dynamically respond to sea-level rise, specifically applied to the Herring River Estuary …

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