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Full-Text Articles in Physical Sciences and Mathematics

Glacial Erosion Rates From The Last Glacial Maximum To Present In Southern Patagonia (50°S), Anastasia Fedotova Dec 2024

Glacial Erosion Rates From The Last Glacial Maximum To Present In Southern Patagonia (50°S), Anastasia Fedotova

Earth Sciences Theses and Dissertations

Over the past few decades, the notion of exogenic processes (e.g. weathering, erosion) contributing to mountain building rather than destruction has become increasingly supported through both direct observations and modeling. As a result, the details of the link between erosion, and therefore climate, and the tectonic evolution of mountain ranges, have progressively become established. One of the key observations emerging from the climate-tectonic debate has been the role of glaciers as powerful landscape sculptors, sensitive to climate signals. The reconstruction of glacial environments evolution and the recovery of patterns of glacial erosion over time have proven key to understanding feedbacks …


Environmental Impact Assessments (Eia): Analysis Of Transboundary Environmental Impact Assessments For The Development Of A Uniform Teia Model, Nicolas Chapa Dec 2024

Environmental Impact Assessments (Eia): Analysis Of Transboundary Environmental Impact Assessments For The Development Of A Uniform Teia Model, Nicolas Chapa

Open Access Theses & Dissertations

This dissertation investigates the evolution, processes, and importance of Environmental Impact Assessments (EIAs), focusing on transboundary EIAs and the need for a uniform framework. Originating from the National Environmental Policy Act (NEPA) of 1969 in the U.S., EIAs have become globally adopted instruments for assessing and mitigating environmental impacts of development projects. This work reiterates historical milestones, strengths, and current limitations of EIAs. Research also included a review of environmental regulations from Mexico, such as the General Law on Ecological Equilibrium and Environmental Protection (LGEEPA). Through several case studies requiring the use of transboundary EIAs, where shared resources and concerns …


Cmos-Based Rotational Spectroscopy: Massive Spectral Fingerprint Generation And Molecular Detection With Deep Learning, Yasamin Fozouni Dec 2024

Cmos-Based Rotational Spectroscopy: Massive Spectral Fingerprint Generation And Molecular Detection With Deep Learning, Yasamin Fozouni

Computer Science and Engineering Theses and Dissertations

Rotational Spectroscopy is a powerful spectral fingerprinting approach that can be used for identifying different gas molecules in a sample. Gas molecules are free to rotate, with inertia, in fixed states of quantized energy. In Rotational Spectroscopy, radiative beams are shown onto a sample to cause an energy-based transition between quantized rotational states. By sweeping the frequency of the radiative beams and monitoring the absorption with a sensor, one can profile the different rotational states, monitoring for energy based transitions. These transitions are dependent on unique properties of the molecules, thus presenting a unique molecular identification fingerprint (in the form …


Composites Developed By The Reaction Of Elemental Sulfur With Biologically Derived Fats And Oils, Katelyn Tisdale Dec 2024

Composites Developed By The Reaction Of Elemental Sulfur With Biologically Derived Fats And Oils, Katelyn Tisdale

All Dissertations

Human civilization’s modern infrastructure relies mainly on cement and petrochemical products. However, the production of these building materials have harmful ecological effects such as green gas emissions, therefore intensifying the need to develop alternative, sustainable structural materials from renewably sourced or waste material precursors. The work presented herein investigates various biomass derived resources that serve as the olefin source for reaction with elemental sulfur, another abundant waste source, via inverse vulcanization to form high strength composites competitive with that of traditional building materials.

Chapter one reviews various techniques that have been developed and executed in an effort towards lignin valorization …


Influence Of Glycopolymer Structure On Amphiphilic, Hybrid, Linear Branched Block Copolymer Properties For Use In Biomedical Applications, Kevin Green Dec 2024

Influence Of Glycopolymer Structure On Amphiphilic, Hybrid, Linear Branched Block Copolymer Properties For Use In Biomedical Applications, Kevin Green

Dissertations

The focus of this dissertation is evaluating and adding fundamental knowledge regarding the structure-property relations of glycopolymers used in the design of hybrid block copolymers (HBC) that are cable of self-assembling into delivery vehicles for biomedical applications. A shift to the utilization of natural materials in the design and fabrication of drug-delivery vehicles has garnered significant attention. Understanding the effects of linear glycopolymers content and composition on the resulting HBCs properties can provide valuable insight into how these materials may be tailored for use in targeted biological applications.

The first chapter introduces current literature on the need for improvement in …


Investigation Of Social Networks Upon Academic Performance And Mental Health, Rachel Izenson Dec 2024

Investigation Of Social Networks Upon Academic Performance And Mental Health, Rachel Izenson

Master's Theses

It has been shown that computing students have a statistically significantly lower overall sense of belongingness compared to other science students. A sense of community is important for many reasons. For example, there are studies that show that a student's sense of belonging correlates with improved academic performance. Our research aims to analyze the sense of belonging among computing students at Cal Poly San Luis Obispo through a network science lens. We surveyed for their sense of belonging, as well as their social network, to understand how friendships impact one's sense of belonging. When student responses were split by gender, …


Sedimentary Characteristics Of Flood Deposits In Coastal And Fluvial Environments: Examples From Washover Fans (North Carolina, Usa) And Floodplain Deposits (Mississippi, Usa), Shara Gremillion Dec 2024

Sedimentary Characteristics Of Flood Deposits In Coastal And Fluvial Environments: Examples From Washover Fans (North Carolina, Usa) And Floodplain Deposits (Mississippi, Usa), Shara Gremillion

Dissertations

Extreme flooding from severe and prolonged meteorological events and / or overbanking rivers are some of the most deadly and expensive disasters globally, impacting millions of lives, the environment, and property. People living in vulnerable areas, such as near coasts and rivers, are the first to be impacted with effects of these flood hazards. Scientific studies and their results can aid communities and officials in planning and preparing for those flood impacts. In this three-part study, flood impacts from coastal storms in North Carolina, and flooding along the Mississippi River (MSR) in the state of Mississippi, USA are assessed from …


Charge Transport In Two Dimensional Systems With Arbitrary Rashba And Dresselhaus Interactions, Abhishek Khanal Dec 2024

Charge Transport In Two Dimensional Systems With Arbitrary Rashba And Dresselhaus Interactions, Abhishek Khanal

All Dissertations

In this thesis we discuss two different transport phenomena that occur in a two-dimensional electron system endowed with linear Rashba and Dresselhaus spin-orbit interactions of arbitrary values. First, in a semiclassical formalism we calculate the non-linear charge currents that appear in response to the simultaneous application of in-plane electric and magnetic fields. Working in a rotated system of coordinates that introduces $\alpha \pm \beta$ as effective couplings on perpendicular directions, we formulate a transport theory that relies on a second order distribution function derived in a local energy approximation and on chiral dependent relaxation times to show that the currents …


Aars Online: A Collaborative Database On The Structure, Function, And Evolution Of The Aminoacyl-Trna Synthetases, Jordan Douglas, Haissi Cui, John J. Perona, Oscar Vargas-Rodriguez, Henna Tyynismaa, Claudia Alvarez Carreno, Jiqiang Ling, Lluis Ribas De Pouplana, Xiang-Lei Yang, Multiple Additional Authors Dec 2024

Aars Online: A Collaborative Database On The Structure, Function, And Evolution Of The Aminoacyl-Trna Synthetases, Jordan Douglas, Haissi Cui, John J. Perona, Oscar Vargas-Rodriguez, Henna Tyynismaa, Claudia Alvarez Carreno, Jiqiang Ling, Lluis Ribas De Pouplana, Xiang-Lei Yang, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

The aminoacyl-tRNA synthetases (aaRS) are a large group of enzymes that implement the genetic code in all known biological systems. They attach amino acids to their cognate tRNAs, moonlight in various translational and non-translational activities beyond aminoacylation, and are linked to many genetic disorders. The aaRS have a subtle ontology characterized by structural and functional idiosyncrasies that vary from organism to organism, and protein to protein. Across the tree of life, the 22 coded amino acids are handled by 16 evolutionary families of Class I aaRS and 21 families of Class II aaRS. We introduce AARS Online, an interactive Wikipedia-like …


(R2098) Dynamic Analysis Of Stochastic Leslie-Gower Biological Predator-Prey Model With Prey Cannibalism, Sada Nand Prasad, Itendra Kumar Universiry Of Delhi, India, Pawan Kumar Dec 2024

(R2098) Dynamic Analysis Of Stochastic Leslie-Gower Biological Predator-Prey Model With Prey Cannibalism, Sada Nand Prasad, Itendra Kumar Universiry Of Delhi, India, Pawan Kumar

Applications and Applied Mathematics: An International Journal (AAM)

In this paper, we study the dynamical analysis of a stochastic Leslie–Gower biological predator– prey model. Earlier, the Leslie–Gower model was studied in the context of biological systems, including cases involving cannibalism. In our model, we investigate the dynamic properties of a stochastic Leslie–Gower predator–prey ecological system using the stability of invariant measures on invariant sets, where the invariant measures are shown to be ergodic. We also conduct a threshold analysis to study the stochastic persistence and extinction of species. Stochastic bifurcation is also examined. The theoretical results are supported by numerical simulations and examples. Intra-species competition is considered and …


(R2116) The Novel Garima Distribution Properties And Nuclear Data Application, Murat Aygün, Ayşe Metin Karakaş Dec 2024

(R2116) The Novel Garima Distribution Properties And Nuclear Data Application, Murat Aygün, Ayşe Metin Karakaş

Applications and Applied Mathematics: An International Journal (AAM)

This research introduces a new two-parameter Marshall-Olkin Garima distribution model. The novel model has many sub-models that are useful in modeling real-life data, such as the extended Garima distribution, exponentiated Garima distribution, exponential distribution, Lindley distribution, Kumaraswamy Garima distribution, and normal distribution. The proposed model demonstrates a high level of suitability in modeling both reliability and survival data. It is flexible in accommodating various failures. The quantile function, density shapes, hazard rate functions, and order statistics are a few of the statistical features that have been explored. Maximum likelihood estimation methods were employed to estimate the parameters. Using five data …


(R2102) Chaos Measure In A Discrete Sir Epidemic Model With Constant Recovery, Sonia Aneja, Itendra Kumar, Sada Nand Prasad Dec 2024

(R2102) Chaos Measure In A Discrete Sir Epidemic Model With Constant Recovery, Sonia Aneja, Itendra Kumar, Sada Nand Prasad

Applications and Applied Mathematics: An International Journal (AAM)

A discrete SIR epidemic model with constant recovery and bilinear incidence rate is investigated for emergence of regular and chaotic behaviour in the context of non linear dynamics and different viable settings. The Euler’s discretization method is employed to transform the continuous epidemic model into discrete model which has been used as the study model. Attention is paid to various bifurcation plots obtained by varying certain system parameters while keeping other parameters constant. Bifurcations indicate regular evolution followed by chaos. Regular and chaotic attractors have been drawn in the process. As part of chaos measure, numerical studies are extended to …


Enhancing Assessment And Feedback In Game Design Programs: Leveraging Generative Ai For Efficient And Meaningful Evaluation, James Hutson, Ben Fulcher, Jay Ratican Dec 2024

Enhancing Assessment And Feedback In Game Design Programs: Leveraging Generative Ai For Efficient And Meaningful Evaluation, James Hutson, Ben Fulcher, Jay Ratican

Faculty Scholarship

The integration of generative AI tools in game design education offers promising ways to streamline the grading, assessment, and feedback processes that are typically labor-intensive. In game design programs, faculty often deal with varied file formats, including 3D models, executable prototypes, videos, and complex game design documents. Traditional methods of assessment and feedback, primarily text-based, struggle to provide timely and actionable insights for students. Furthermore, only a small percentage of top students consistently review and apply feedback, leading to inefficiencies. This article explores how generative AI tools can augment these processes by automating aspects of grading, generating more personalized and …


Thermal Modeling Of Cooling Time Of Submarine Dacite Lapilli Tuff: Brothers Volcano, Kermadec Arc, Kyler Byrd Dec 2024

Thermal Modeling Of Cooling Time Of Submarine Dacite Lapilli Tuff: Brothers Volcano, Kermadec Arc, Kyler Byrd

Master's Theses

Little is known about submarine volcanoes' eruptive histories and styles, even though they are essential to developing island arc systems and represent the second largest volcanic systems on Earth. Scientific drilling allows for the opportunity to study these systems. This study focused on two drill sites on Brothers volcano from IODP Expedition 376: Site U1528, located on the resurgent cone, and Site U1530, located on the caldera rim. Expedition researchers analyzed samples for clast radius, density, thermal conductivity, and specific heat. This data was then entered into the heat transfer equation of a sphere to create a cooling curve model …


Investigating Nekton Response To Changing Salinities In The Mississippi Sound: An Experimental And Statistical Approach, Adam Murray Dec 2024

Investigating Nekton Response To Changing Salinities In The Mississippi Sound: An Experimental And Statistical Approach, Adam Murray

Master's Theses

The Mississippi Sound provides nursery habitats for many coastal species and is recognized for its commercial fisheries. Previous freshening events linked to the Bonnet Carré Spillway, a Mississippi River flood diversion structure, proved catastrophic for oyster populations in the Mississippi Sound, but effects on mobile fish and shellfish species are not well-defined. The planned Mid-Breton Sediment Diversion (MBSD), an initiative to combat wetland loss, is also forecasted to lower salinities in the region, increasing the need to better understand responses of commercially and ecologically important species to freshening events. The objective of this study was to characterize effects of salinity …


A Web Application For Comparing Llm And Knowledge Graph Performance On Cybersecurity Queries, Major Schwartz Dec 2024

A Web Application For Comparing Llm And Knowledge Graph Performance On Cybersecurity Queries, Major Schwartz

Honors Theses

The evolution of cybersecurity has led to a spike in digital threats, both in frequency and complexity, necessitating advanced, intelligent solutions to protect sensitive information. Traditional defense mechanisms are increasingly inadequate, pushing cybersecurity professionals to seek innovative approaches for threat detection, response, and data analysis. This thesis investigates the integration of Large Language Models (LLMs) and Knowledge Graphs into cybersecurity workflows to address these challenges. Specifically, it explores the development of a web application that enables real-time, interactive use of state-of-the-art LLMs, such as OpenAI’s GPT-4 and similar models, for improved threat response and workflow efficiency. Built with a React …


(R2097) Impact Of Inclined Magnetic Field On Two Immiscible Viscous Fluids Flow In A Porous Channel With Variable Permeability: A Finite Difference Technique, Angad Prasad, P. K. Singh Dec 2024

(R2097) Impact Of Inclined Magnetic Field On Two Immiscible Viscous Fluids Flow In A Porous Channel With Variable Permeability: A Finite Difference Technique, Angad Prasad, P. K. Singh

Applications and Applied Mathematics: An International Journal (AAM)

This paper is concerned with the flow of two immiscible, viscous, incompressible, and electrically conducting fluids in a horizontal channel containing a porous material under an inclined magnetic field. The flow is propelled by a consistent pressure gradient. These two fluids have different viscosities in two separate layers of equal width. The fluid in the upper layer has a lower viscosity compared to the fluid in the lower layer. The Permeability of a porous medium is variable with the transverse direction. The Brinkman equation is employed to describe fluid flow within a porous medium. Numerical solutions for velocity and volumetric …


(R2117) Cost Optimization Of Queueing System With Differentiated Vacations And Reneging Of Customers, Poonam Gupta, Rajni Gupta Dec 2024

(R2117) Cost Optimization Of Queueing System With Differentiated Vacations And Reneging Of Customers, Poonam Gupta, Rajni Gupta

Applications and Applied Mathematics: An International Journal (AAM)

This manuscript deals with an infinite-capacity queueing system under multiple differentiated working vacations and customers’ impatience. The first vacation is assumed to be a working vacation where the server, instead of being idle, serves the customers at a lower rate. In contrast, the second one is considered a non-working vacation of a different duration. The customers may leave the system at any time due to long delays in service during vacations but, via some convincing mechanisms, they are retained in the system. The operating characteristics of the system are obtained in a steady state. The results obtained are illustrated numerically …


Spatial-Textural Study Of Siliciclastics In A Navajo Sandstone Carbonate Lens, Christopher L. Rupe Dec 2024

Spatial-Textural Study Of Siliciclastics In A Navajo Sandstone Carbonate Lens, Christopher L. Rupe

Loma Linda University Electronic Theses, Dissertations & Projects

Flat-lying carbonate deposits in the Lower Jurassic Navajo Sandstone have long been interpreted as interdune lacustrine deposits. This dissertation critically assesses such inference through the study of an exceptionally well-preserved carbonate deposit in the Trough Canyon area, northwest of Moab, Utah. Thickness measurements along multiple cross-sectional exposures were used to construct an isopach map, approximating the original size and lenticular geometry of the deposit. Dip directions were recorded from foreset strata in cross-bed sets stratigraphically overlying the deposit to infer the approximately coeval direction of siliciclastic transport across the carbonate basin. These data sets yielded a contextual framework for studying …


Front Matter Dec 2024

Front Matter

The Synapse: Intercollegiate science magazine

No abstract provided.


Giving A Voice To The Voiceless: The Benefits Of Music Therapy For Children With Autism, Isabelle Brown-Lyden Dec 2024

Giving A Voice To The Voiceless: The Benefits Of Music Therapy For Children With Autism, Isabelle Brown-Lyden

The Synapse: Intercollegiate science magazine

No abstract provided.


The Magic Of Bioluminescence: How Animals Illuminate The Dark, Eleanor St. Clair Dec 2024

The Magic Of Bioluminescence: How Animals Illuminate The Dark, Eleanor St. Clair

The Synapse: Intercollegiate science magazine

No abstract provided.


To Mine Or Not To Mine?: Discovery Of Polymetallic Nodules And Discussions On Deep-Sea Mining, Haze Doleys Dec 2024

To Mine Or Not To Mine?: Discovery Of Polymetallic Nodules And Discussions On Deep-Sea Mining, Haze Doleys

The Synapse: Intercollegiate science magazine

No abstract provided.


Don't Waste Heat! Innovations In Energy Conversion And Conservation From The London Tube, Noah Hamaoui Dec 2024

Don't Waste Heat! Innovations In Energy Conversion And Conservation From The London Tube, Noah Hamaoui

The Synapse: Intercollegiate science magazine

No abstract provided.


Meet The Staff Dec 2024

Meet The Staff

The Synapse: Intercollegiate science magazine

No abstract provided.


Back Cover, Julia Stuart Dec 2024

Back Cover, Julia Stuart

The Synapse: Intercollegiate science magazine

No abstract provided.


Density Functional Theory And Machine Learning Analysis Of C—C Reductive Coupling From Terminal Cyanido And Cyaphido Complexes, Roberto Magdiel Escobar Dec 2024

Density Functional Theory And Machine Learning Analysis Of C—C Reductive Coupling From Terminal Cyanido And Cyaphido Complexes, Roberto Magdiel Escobar

Theses and Dissertations

Carbon–carbon (C–C) bond activation has gained increased attention as a direct method for the synthesis of pharmaceuticals and industrial chemistry. Due to the thermodynamic stability and kinetic inaccessibility of the C–C bonds, however, activation of C–C bonds by homogeneous transition-metal catalysts under mild homogeneous conditions is still a challenge. Most of the systems in which the activation occurs either have aromatization or relief of ring strain as the primary driving force. The activation of unstrained C–C bonds of phosphaalkynes does not have this advantage. This study employs Density Functional Theory (DFT) calculations using the Gaussian16 package to elucidate and compare …


Universal Shape Replication Via Self-Assembly With Signal-Passing Tiles, Andrew Alseth, Daniel Hader, Matthew J. Patitz Dec 2024

Universal Shape Replication Via Self-Assembly With Signal-Passing Tiles, Andrew Alseth, Daniel Hader, Matthew J. Patitz

Computer Science and Computer Engineering Faculty Publications and Presentations

In this paper, we investigate shape-assembling power of a tile-based model of self-assembly called the Signal-Passing Tile Assembly Model (STAM). In this model, the glues that bind tiles together can be turned on and off by the binding actions of other glues via “signals”. Specifically, the problem we investigate is “shape replication” wherein, given a set of input assemblies of arbitrary shape, a system must construct an arbitrary number of assemblies with the same shapes and, with the exception of size-bounded junk assemblies that result from the process, no others. We provide the first fully universal shape replication result, namely …


Landscaping Impacts On Urban Soil Development, Fry Lundgren Dec 2024

Landscaping Impacts On Urban Soil Development, Fry Lundgren

University Honors Theses

Urban soils can play a key role in flood mitigation, water filtration, and supporting urban plant communities, however many are highly disturbed due to development and management practices. Although full recovery will take time (centuries), in the short term managing soils in ways that conserve organic matter inputs and promote nutrient cycling can support important soil functions and likely promote long term development. To understand how landscaping impact soil development on PSU campus, organic matter content, moisture content, and respiration rates were measured in soils from four area types with different long term weed management strategies (mulch- M; sustained plant …


Assessing Reproducibility Challenges In Clinical Metabolics, Darcy Lin Cochran Dec 2024

Assessing Reproducibility Challenges In Clinical Metabolics, Darcy Lin Cochran

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Current metabolomics research is expanding to be multiplatform and interdisciplinary. Metabolomic analysis has the potential to provide detailed insight into any biological system of interest to analyze the underlying molecular mechanisms of variables like environment, disease, and genetics. Human clinical metabolomics is a major research area that is often focused on finding biomarkers or panels of biomarkers for different diseases. However, results are difficult to compare across different laboratories since the field of metabolomics has yet to widely adopt best practices for sample preparation, data acquisition and data processing, results are difficult to compare across different laboratories.

This thesis focuses …