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Cross-Interactions Of Amyloid Proteins: Implications For Aggregation Dynamics And Disease Pathology, Zhiyuan Song Dec 2024

Cross-Interactions Of Amyloid Proteins: Implications For Aggregation Dynamics And Disease Pathology, Zhiyuan Song

All Dissertations

Amyloid aggregation is a pervasive form of protein misfolding implicated in the pathology of several prominent human diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD), and type 2 diabetes (T2D). These diseases are marked by the accumulation of amyloid fibrils and toxic oligomers, which are highly dynamic and heterogeneous, posing challenges for understanding their roles in disease progression. Despite significant advances in the diagnosis and management of these conditions, no definitive cure is available. We investigate amyloid aggregation and cross-seeding, with a focus on amyloid-beta (Aβ), tau, alpha-synuclein (αS), and human islet amyloid polypeptide (IAPP) through discrete molecular dynamics (DMD) …


Graphene-Based Antennas Utilizing Polyvinylidene Fluoride (Pvdf) Substrates For Attenuation, Josef Frankhouse Dec 2024

Graphene-Based Antennas Utilizing Polyvinylidene Fluoride (Pvdf) Substrates For Attenuation, Josef Frankhouse

Mechanical Engineering Undergraduate Honors Theses

In this study, a Terahertz (THz) band antenna which can regulate its own resonant frequency without the requirement of manual adjustment is simulated. A polyvinylidene fluoride (PVDF) substrate is applied onto a rectangular graphene patch antenna. With a voltage potential applied onto the PVDF, the patch antenna can attenuate its frequency by physically changing the shape of the antenna, and in turn its resonant frequency. These antennas are within a 0.1 THz band between 1.32 THz to 1.22 THz measured from a radial bend of a flat surface to r = 75 , fitting into a return loss (S11 …


Enhancing Student Learning Of The Physics Of The Human Eye In The Context Of Computer Vision Syndrome During Covid-19, Liang Zeng, Guang Zeng Dec 2024

Enhancing Student Learning Of The Physics Of The Human Eye In The Context Of Computer Vision Syndrome During Covid-19, Liang Zeng, Guang Zeng

Physics & Astronomy Faculty Publications

No abstract provided.


The Temperature Versus Orbital Period Relation Of Am Cvns: Insights From Their Donors, Colin W. Macrie, Liliana Rivera Sandoval, Yuri Cavecchi, Tin Long Sunny Wong, Manuel Pichardo Marcano Dec 2024

The Temperature Versus Orbital Period Relation Of Am Cvns: Insights From Their Donors, Colin W. Macrie, Liliana Rivera Sandoval, Yuri Cavecchi, Tin Long Sunny Wong, Manuel Pichardo Marcano

Physics & Astronomy Faculty Publications

We studied the spectral energy distribution of 22 known AM CVns with orbital periods (Porb) larger than 35 minutes using multiwavelength public photometric data to estimate the effective temperature of the accreting white dwarf. We find an infrared (IR) excess in all systems when compared to a single blackbody, both when the disk should be extended and when it should be truncated by the accretor's magnetic field. This suggests a dominant contribution from the donor to the IR flux. When fitting two blackbodies, the temperature of the hot component decreases with Porb, as expected by evolutionary models. …


Analysis Of A Gravity Wave Horizontal Blocking Event Using Hodograph Techniques Applied To Sodium Lidar Data, Neal R. Criddle Dec 2024

Analysis Of A Gravity Wave Horizontal Blocking Event Using Hodograph Techniques Applied To Sodium Lidar Data, Neal R. Criddle

All Graduate Theses and Dissertations, Fall 2023 to Present

Atmospheric gravity waves are ubiquitous and important events in Earth’s atmosphere with impacts on space weather and associated technological effects. The population of gravity waves is determined by their formation mechanisms, and their interactions with the background atmosphere. These gravity waves transport energy and momentum into the near Earth space environment, and are responsible for movement of chemical species. Predicting the occurrence of space weather effects, then, is in part a process requiring the characterization of gravity waves. Case studies of unique and interesting gravity wave events are an important part of this process. These allow for the investigation of …


The Temperature Trend In The Upper Mesosphere Between ∼84 Km And 98 Km Based On Diurnal Cycle Observations By A Na Lidar At Middle Latitudes Between 2002 And 2017, Melania Carolina Pena Dec 2024

The Temperature Trend In The Upper Mesosphere Between ∼84 Km And 98 Km Based On Diurnal Cycle Observations By A Na Lidar At Middle Latitudes Between 2002 And 2017, Melania Carolina Pena

All Graduate Theses and Dissertations, Fall 2023 to Present

Carbon dioxide is one of the main greenhouse gasses that contributes to maintaining Earth’s warm global temperature in its atmosphere. Recent studies have indicated that this cooling trend has been determined to vary between less than 1 K/decade or 2 K/decade. However, these results have been determined using data that have been obtained using nighttime lidar observations and potentially do not give the complete picture on how the cooling trend is behaving. The main goal of this research is to understand the behavior of the linear temperature trend between the daytime and nighttime profiles using a 16-year dataset (2002-2017), when …


Using The Schism Model And Hf Radar Data To Study Surface Currents In Texas Bays: A Case Study Of Sabine Lake (Sl) And Galveston Bay (Gb)., Cletus Ozoemena Ogbodo Dec 2024

Using The Schism Model And Hf Radar Data To Study Surface Currents In Texas Bays: A Case Study Of Sabine Lake (Sl) And Galveston Bay (Gb)., Cletus Ozoemena Ogbodo

Open Access Theses & Dissertations

Surface currents study provides invaluable understanding into the physical dynamics of oceans, bays, estuaries, and nearshore environments, offering critical insights about water movement and related coastal processes. These currents play a fundamental role in understanding the state of estuarine and marine systems, such as their effects on sediment transport, heat distribution and climate change, nutrient distribution, and pollutant dispersal. In addition, surface current data provides significant economic and ecological implications for coastal communities essential for managing resources effectively and ensuring the resilience of coastal regions against environmental and anthropogenic pressures. This study was driven by the need to address the …


Ohmic Contacts For Fabrication Of Sic Cmos Devices, Anthony Di Mauro Dec 2024

Ohmic Contacts For Fabrication Of Sic Cmos Devices, Anthony Di Mauro

Graduate Theses and Dissertations

Today’s world of electronics is dominated by semiconductor devices which utilize silicon as their substrate material. Though, silicon is not ideal for semiconductor devices in high-voltage or high-temperature applications. Additionally, the efficiency of silicon devices becomes drastically reduced in nonideal operating conditions. Therefore, finding alternatives to silicon?based devices has been a topic for decades now. A few great candidates to replace silicon devices for said applications include Silicon Carbide (SiC), Gallium Nitride (GaN), and Aluminum Arsenide (AlAs). SiC has grown its reputation as the best candidate, when compared to other potential alternatives, due to its wide bandgap, high operating frequency, …


Impact Of Weather Systems On Uav Parameters Using Computational Fluid Dynamics, Saif Aljuhaishi, Yaseen K. Al-Timimi, Basim I. Wahab Nov 2024

Impact Of Weather Systems On Uav Parameters Using Computational Fluid Dynamics, Saif Aljuhaishi, Yaseen K. Al-Timimi, Basim I. Wahab

Karbala International Journal of Modern Science

Since drones cannot fly in any kind of weather, they are not safe for time-sensitive activities. The study examines how the passage of weather systems in Iraq leads to the ban on drone flights, and how these weather conditions impact the aerodynamic forces of the drone. Hourly climate data for the study area were obtained from ECMWF ERA5 and CAMS in NetCDF format for four climate stations (Erbil, Baghdad, Rutbah, and Basrah). A ScanEagle drone was chosen for this study. The Python programming language was used to perform mathematical operations to calculate the ban on drone flights. ArcGIS 10.8 was …


A B-Polynomial Approach To Approximate Solutions Of Pdes With Multiple Initial Conditions, Muhammad I. Bhatti, Md. Habibur Rahman Nov 2024

A B-Polynomial Approach To Approximate Solutions Of Pdes With Multiple Initial Conditions, Muhammad I. Bhatti, Md. Habibur Rahman

Physics & Astronomy Faculty Publications

In this article, we present a novel B-Polynomial Approach for approximating solutions to partial differential equations (PDEs), addressing the multiple initial conditions. Our method stands out by utilizing two-dimensional Bernstein polynomials (B-polynomials) in conjunction with their operational matrices to effectively manage the complexity associated with PDEs. This approach not only enhances the accuracy of solutions but also provides a structured framework for tackling various boundary conditions. The PDE is transformed into a system of algebraic equations, which are then solved to approximate the PDE solution. The process is divided into two main steps: First, the PDE is integrated to incorporate …


Separating A Particle's Mass From Its Momentum, Mordecai Waegell, Jeff Tollaksen, Yakir Aharonov Nov 2024

Separating A Particle's Mass From Its Momentum, Mordecai Waegell, Jeff Tollaksen, Yakir Aharonov

Mathematics, Physics, and Computer Science Faculty Articles and Research

The Quantum Cheshire Cat experiment showed that when weak measurements are performed on pre- and post-selected system, the counterintuitive result has been obtained that a neutron is measured to be in one place without its spin, and its spin is measured to be in another place without the neutron. A generalization of this effect is presented with a massive particle whose mass is measured to be in one place with no momentum, while the momentum is measured to be in another place without the mass. The new result applies to any massive particle, independent of its spin or charge. A …


Multiphase Electrochemical Li-Ion Intercalation In Iron Selenite: Evidence Of Fe³⁺/⁴⁺ Redox And Single-Crystal-To-Single-Crystal Topochemical Transformation During Chemical Lithiation, Sutapa Bhattacharya, Aleksandr V. Chernatynskiy, Amitava Choudhury Nov 2024

Multiphase Electrochemical Li-Ion Intercalation In Iron Selenite: Evidence Of Fe³⁺/⁴⁺ Redox And Single-Crystal-To-Single-Crystal Topochemical Transformation During Chemical Lithiation, Sutapa Bhattacharya, Aleksandr V. Chernatynskiy, Amitava Choudhury

Physics Faculty Research & Creative Works

An iron selenite-based cathode compound, LiFe(SeO3)2, is synthesized via a simple hydrothermal route. The bulk purity of the compound is confirmed by powder X-ray diffraction (PXRD), Mössbauer spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The crystal structure determined from the single-crystal X-ray diffraction and Rietveld refinement of synchrotron PXRD data perfectly matches the previously reported structure in the I4̅2d space group. The crystal structure is built up of edge-sharing of FeO6 octahedra and LiO4 tetrahedra interconnected by SeO3 trigonal pyramidal units, forming a three-dimensional open framework network with channels through all three axes. …


Study On The Seasonal Endobacterial Profile Of Avicennia Officinalis, Focusing On Core Bacterial Consortia Within Mangrove Pneumatophores, Devi R R, Vinod Prabhakar Nov 2024

Study On The Seasonal Endobacterial Profile Of Avicennia Officinalis, Focusing On Core Bacterial Consortia Within Mangrove Pneumatophores, Devi R R, Vinod Prabhakar

Karbala International Journal of Modern Science

Microhabitats are smaller pockets of ecosystems with unique conditions and they serve as major contributors of species richness. Mangrove plants offer a diverse array of such microhabitats (rhizosphere, phyllosphere, endosphereetc), and the inhabitant bacteria benefit the host by providing better salinity tolerance, faster and better nutrient mobilization, protection from phytopathogens and assistance in seed germination. Identification of such beneficial bacteria,their growth requirementsandmetabolism, willhave direct application in the field of agriculture and ecosystem restoration. Hence in this study, effort has been made to elucidate the seasonal numerical and compositional profile of pneumatophore bacterial consortia of Avicennia officinalis, from the mangrove …


Bound States And Particle Production By Breather-Type Background Field Configurations, Abhishek Rout, Brett Altschul Nov 2024

Bound States And Particle Production By Breather-Type Background Field Configurations, Abhishek Rout, Brett Altschul

Faculty Publications

We investigate the interaction of fermion fields with oscillating domain walls, inspired by breather-type solutions of the sine-Gordon equation, a nonlinear system of fundamental importance. Our study focuses on the fermionic bound states and particle production induced by a time-dependent scalar background field. The fermions couple to two domain walls undergoing harmonic motion, and we explore the resulting dynamics of the fermionic wave functions. We demonstrate that while fermions initially form bound states around the domain walls, the energy provided by the oscillatory motion of the scalar field induces an outward flux of fermions and antifermions, leading to particle production …


The Impact Of Cumulative And Acute Loading On Achilles Tendon Health, Performance, And Reported Pain In Collegiate Gymnasts, Julio Serrano Samayoa Nov 2024

The Impact Of Cumulative And Acute Loading On Achilles Tendon Health, Performance, And Reported Pain In Collegiate Gymnasts, Julio Serrano Samayoa

Electronic Theses and Dissertations

Gymnasts are at a high risk of Achilles tendon (AT) injuries due to intense loads during takeoffs and landings. To better understand better the relationship between impact loading and its effects on tendon adaptation and athletic performance, this study uses Inertial Measurement Units (IMUs) to track AT loading across a collegiate gymnastics season. This data were compared against physiological and athletic performance metrics, obtained through force plates and ultrasound imaging, to explore how mechanical load influences reported pain and athletic performance. Results varied, with cumulative impacts being correlated with improved jump height (Spearman 0.362, Pearson 0.348), while peak power and …


Applying Machine‐Learning Methods To Laser Acceleration Of Protons: Lessons Learned From Synthetic Data, Ronak Desai, Thomas Zhang, J. J. Felice, Ricky Oropeza, Joseph R. Smith, Alona Kryshchenko, Chris Orban, Michael L. Dexter, Anil K. Patnaik Nov 2024

Applying Machine‐Learning Methods To Laser Acceleration Of Protons: Lessons Learned From Synthetic Data, Ronak Desai, Thomas Zhang, J. J. Felice, Ricky Oropeza, Joseph R. Smith, Alona Kryshchenko, Chris Orban, Michael L. Dexter, Anil K. Patnaik

Faculty Publications

In this study, we consider three different machine-learning methods—a three-hidden-layer neural network, support vector regression, and Gaussian process regression—and compare how well they can learn from a synthetic data set for proton acceleration in the Target Normal Sheath Acceleration regime. The synthetic data set was generated from a previously published theoretical model by Fuchs et al. 2005 that we modified. Once trained, these machine-learning methods can assist with efforts to maximize the peak proton energy, or with the more general problem of configuring the laser system to produce a proton energy spectrum with desired characteristics. In our study, we focus …


A Simple And Low-Cost Method For Generating Short Laser Pulses, Daniel Fisher Nov 2024

A Simple And Low-Cost Method For Generating Short Laser Pulses, Daniel Fisher

Undergraduate Research Symposium Posters

A simple, portable method is described and demonstrated for generating short optical pulses (~ 1 μsec) from a continuous wave (CW) source using a rotating pinhole. A CW 633nm HeNe beam was focused onto a 225 μm diameter stainless steel pinhole, which was rotated up to 1000 Hz using an optical chopper wheel. The pulsed light was then focused onto a silicon photodetector and read by an oscilloscope. This novel setup aims to bridge the gap between pulsed laser performance and price for wide application in spectroscopy methods, industrial laser peening, and medical treatments. This will be the first publication …


Detection Of Methane Leaks By The Use Of Mid-Range Infrared Camera, Jared Rosario, Oscar Salcido Nov 2024

Detection Of Methane Leaks By The Use Of Mid-Range Infrared Camera, Jared Rosario, Oscar Salcido

Undergraduate Research Symposium Posters

Timely detection of methane leaks from natural gas infrastructure, like pipelines and valves, is essential for mitigating environmental and safety risks. This research focuses on using mid-wave infrared (MwIR) cameras on unmanned aerial systems (UAS) to detect leaks. By leveraging machine learning, the study aims to develop an efficient, real-time methane inspection system that operates directly on embedded processors on UAS platforms.

This project employs the FLIR G300a OGI camera for remote gas inspection, utilizing video preprocessing and optical flow to mask gas plumes in footage. The YOLOv8 deep learning model is used to detect gas pixels and segment the …


A Class Of Stable Nonlinear Non-Hermitian Skin Modes, Hamed Ghaemi-Dizicheh Nov 2024

A Class Of Stable Nonlinear Non-Hermitian Skin Modes, Hamed Ghaemi-Dizicheh

Physics & Astronomy Faculty Publications

The non-Hermitian skin effect (NHSE) is a well-known phenomenon in open topological systems that causes a large number of eigenstates to become localized at the boundary. Although many aspects of its theory have been investigated in linear systems, this phenomenon remains novel in nonlinear models. In the first step of this paper, we look at the conditions for the presence of quasi-skin modes in a semi-infinite, one-dimensional, nonlinear, nonreciprocal lattice. In the following phase, we explore the survival time of the quasi-skin mode in a finite nonlinear lattice with open edges. We study the dependency of the survival time on …


High-Coherence Kerr-Cat Qubit In 2d Architecture, Ahmed Hajr, Bingcheng Qing, Ke Wang, Gerwin Koolstra, Zahra Pedramrazi, Ziqi Kang, Larry Chen, Long B. Nguyen, Christian Jünger, Noah Goss, Irwin Huang, Bibek Bhandari, Nicholas E. Frattini, Shruti Puri, Justin Dressel, Andrew N. Jordan, David I. Santiago, Irfan Siddiqi Nov 2024

High-Coherence Kerr-Cat Qubit In 2d Architecture, Ahmed Hajr, Bingcheng Qing, Ke Wang, Gerwin Koolstra, Zahra Pedramrazi, Ziqi Kang, Larry Chen, Long B. Nguyen, Christian Jünger, Noah Goss, Irwin Huang, Bibek Bhandari, Nicholas E. Frattini, Shruti Puri, Justin Dressel, Andrew N. Jordan, David I. Santiago, Irfan Siddiqi

Mathematics, Physics, and Computer Science Faculty Articles and Research

The Kerr-cat qubit is a bosonic qubit in which multiphoton Schrödinger cat states are stabilized by applying a two-photon drive to an oscillator with a Kerr nonlinearity. The suppressed bit-flip rate with increasing cat size makes this qubit a promising candidate to implement quantum error correction codes tailored for noise-biased qubits. However, achieving strong light-matter interactions necessary for stabilizing and controlling this qubit has traditionally required strong microwave drives that heat the qubit and degrade its performance. In contrast, increasing the coupling to the drive port removes the need for strong drives at the expense of large Purcell decay. By …


Disciplinary Policy Research On Science Development Strategies For Crewed Lunar Exploration, Wei Yang, Yuyang He, Jinting Kang, Ruiyi Chen, Huihong Cheng, Li Sun, Pan Deng, Yong Wei, Yangting Lin, Xianhua Li Nov 2024

Disciplinary Policy Research On Science Development Strategies For Crewed Lunar Exploration, Wei Yang, Yuyang He, Jinting Kang, Ruiyi Chen, Huihong Cheng, Li Sun, Pan Deng, Yong Wei, Yangting Lin, Xianhua Li

Bulletin of Chinese Academy of Sciences (Chinese Version)

In order to better serve China’s crewed lunar exploration, this study researched and analyzed the current status of lunar exploration and planetary science research in China and the United States. Additionally, we conducted interviews and a questionnaire survey with experts in planetary science and deep-space exploration, and formed the following four policy recommendations: 1) Strengthening the layout and management of the disciplines of lunar and planetary sciences, and setting up a long-term and stable funding mechanism; 2) Improving the system of talent cultivation, and encouraging young talents to participate in deep-space exploration missions; 3) Strengthening the protection of original ideas, …


A Class Of Stable Nonlinear Non-Hermitian Skin Modes, Hamed Ghaemi-Dizicheh Nov 2024

A Class Of Stable Nonlinear Non-Hermitian Skin Modes, Hamed Ghaemi-Dizicheh

Physics & Astronomy Faculty Publications

The non-Hermitian skin effect (NHSE) is a well-known phenomenon in open topological systems that causes a large number of eigenstates to become localized at the boundary. Although many aspects of its theory have been investigated in linear systems, this phenomenon remains novel in nonlinear models. In the first step of this paper, we look at the conditions for the presence of quasi-skin modes in a semi-infinite, one-dimensional, nonlinear, nonreciprocal lattice. In the following phase, we explore the survival time of the quasi-skin mode in a finite nonlinear lattice with open edges. We study the dependency of the survival time on …


Improving The Performance Of The Modal Holographic Wavefront Sensor By Adapting To Prevailing Turbulence Conditions: Experimental Verification, Andreas Zepp, Emma Branigan, Kevin Murphy, Szymon Gladysz Nov 2024

Improving The Performance Of The Modal Holographic Wavefront Sensor By Adapting To Prevailing Turbulence Conditions: Experimental Verification, Andreas Zepp, Emma Branigan, Kevin Murphy, Szymon Gladysz

Conference Papers

The modal holographic wavefront sensor offers a promising alternative to established wavefront sensing techniques. Since the strengths of individual aberration modes are directly measured, there is no need for time-consuming signal processing and wavefront reconstruction. Bandwidths up to three orders of magnitude higher than those of commercial wavefront sensors can in principle be achieved. However, in practice the accuracy of measurements is compromised by intermodal crosstalk, which arises when the wavefront exhibits additional aberrations to those encoded in the modal wavefront sensor. This issue is particularly prominent when measuring wavefronts disturbed by atmospheric turbulence. To mitigate the effects of intermodal …


Time Domain Spectral Lidar Enabled By Cascaded Raman In A Hydrogen-Filled Transmitter, Richard K. Martin, Trevor L. Courtney, Arielle M. Adams, Daniel E. Leaird, Luke Ausley, Christian K. Keyser Nov 2024

Time Domain Spectral Lidar Enabled By Cascaded Raman In A Hydrogen-Filled Transmitter, Richard K. Martin, Trevor L. Courtney, Arielle M. Adams, Daniel E. Leaird, Luke Ausley, Christian K. Keyser

Faculty Publications

We introduce what we believe to be novel spectral light detection and ranging (LiDAR) architectures that enable ultra-compact systems by a transition from spectral signal processing in space (gratings) to processing in time. The architectures leverage temporal dispersion and the unique spectro-temporal waveforms produced from the cascaded Raman scattering generated in the (H2) filled hollow core fiber. The characterized Raman source yields as many as six Raman orders from 1.06-1.70 μm; their unique spectro-temporal waveforms are measured. System performance simulations based on measured Raman waveforms show that high accuracy measurement of range and reflectivity are possible with proper …


Limitations Of Beam-Control Compensation, Matthew Kalensky, Darren Getts, Matthias T. Banet, Derek J. Burrell, Milo W. Hyde, Mark F. Spencer Nov 2024

Limitations Of Beam-Control Compensation, Matthew Kalensky, Darren Getts, Matthias T. Banet, Derek J. Burrell, Milo W. Hyde, Mark F. Spencer

Faculty Publications

In this paper, we use wave-optics simulations to explore the limitations of beam-control compensation. We evaluate performance in terms of the normalized power in a diffraction-limited bucket for the cases of no beam-control compensation, perfect phase compensation, and perfect full-field compensation. From these results, we are able to arrive at the following conclusions: (1) without any form of beam-control compensation, performance begins to degrade when D/r0 > 1; (2) with perfect phase compensation, performance begins to degrade when D/r0 > 1 and (λ/r0)/θ0 > 1; and (3) with perfect full-field compensation, performance begins to degrade when D/r0 …


Simulations, Modeling And Data Analysis Of Parity Violating Electron Scattering Experiments, Yufan Chen Nov 2024

Simulations, Modeling And Data Analysis Of Parity Violating Electron Scattering Experiments, Yufan Chen

Doctoral Dissertations

In the Standard Model (SM) of nuclear and particle physics, parity violation is incorporated through the representation of the weak interaction as a chiral gauge interaction. Only the left-handed components of particles and right-handed components of antiparticles participate in weak interactions in the Standard Model. This implies that parity is asymmetric for the weak interaction. Parity violating electron scattering (PVES) experiments are designed to probe the physics parameters related to the SM, with the possibility to discover physics beyond the SM (BSM) by measuring the parity violating asymmetry 𝐴𝑃𝑉 of longitudinally polarized electrons scattered off unpolarized targets with high precision. …


Measurement Of Multi-Jet Ratios In The Atlas Experiment, Zahra Farazpay Nov 2024

Measurement Of Multi-Jet Ratios In The Atlas Experiment, Zahra Farazpay

Doctoral Dissertations

This dissertation presents a comprehensive study of multi-jet cross-section ratios using proton-proton collision data collected by the ATLAS detector during Run 2 of the Large Hadron Collider (LHC) at a center-of-mass energy of √ s = 13TeV. By examining these ratios across different energy scales, the analysis provides valuable insights into the running of the strong coupling constant, αs, a fundamental parameter in Quantum Chromodynamics (QCD) that dictates the strength of the strong interaction. The running of αs—its variation with energy—is crucial for understanding QCD, yet it remains one of the least precisely known aspects of the theory. In this …


Computational Design Of Complex Concentrated Alloys, Hamid Sharifi Nov 2024

Computational Design Of Complex Concentrated Alloys, Hamid Sharifi

Doctoral Dissertations

A high-throughput parameterization of modified embedded atom model (MEAM) interatomic potentials for combinations of Cu, Ti, Ni, Cr, Co, Al, Fe, and Mn was carried out using a genetic algorithm. Unary systems were parameterized based on DFT calculations and experimental results. MEAM potentials for 28 binary and 56 ternary combinations of the elements were parameterized to DFT results that were carried out with semi-automated frameworks. Specific attention was made to reproduce properties that impact compositional segregation, material strength, and mechanics. Utilizing the MEAM interatomic potentials and a Monte Carlo scheme, phase segregation in the CrNiCo, CuNiCr and CuNiCo fcc alloys …


Reduced K+ Build-Up In T-Tubules Contributes To Resistance Of The Diaphragm To Myotonia, Jessica H. Myers, Kirsten Denman, Chris Dupont, Brent D. Foy, Mark M. Rich Nov 2024

Reduced K+ Build-Up In T-Tubules Contributes To Resistance Of The Diaphragm To Myotonia, Jessica H. Myers, Kirsten Denman, Chris Dupont, Brent D. Foy, Mark M. Rich

Physics Faculty Publications

Patients with myotonia congenita suffer from slowed muscle relaxation caused by hyperexcitability. The diaphragm is only mildly affected in myotonia congenita; discovery of the mechanism underlying its resistance to myotonia could identify novel therapeutic targets. Intracellular recordings from two mouse models of myotonia congenita revealed the diaphragm had less myotonia than either the extensor digitorum longus (EDL) or the soleus muscles. A mechanism contributing to resistance of the diaphragm to myotonia was reduced depolarization of the interspike membrane potential during repetitive firing of action potentials, a process driven by build-up of K+ in small invaginations of muscle membrane known as …


Battle Of The Ch Motions: Aliphatic Vs Aromatic Contributions To Astronomical Pah Emission And Exploration Of The Aliphatic, Aromatic, And Ethynyl Ch Stretches, Vincent J. Esposito, Salma Bejaoui, Brant E. Billinghurst, Christiaan Boersma, Ryan C. Fortenberry, Farid Salama Nov 2024

Battle Of The Ch Motions: Aliphatic Vs Aromatic Contributions To Astronomical Pah Emission And Exploration Of The Aliphatic, Aromatic, And Ethynyl Ch Stretches, Vincent J. Esposito, Salma Bejaoui, Brant E. Billinghurst, Christiaan Boersma, Ryan C. Fortenberry, Farid Salama

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Strong anharmonic coupling between vibrational states in polycyclic aromatic hydrocarbons (PAH) produces highly mixed vibrational transitions that challenge the current understanding of the nature of the astronomical mid-infrared PAH emission bands. Traditionally, PAH emission bands have been characterized as either aromatic or aliphatic, and this assignment is used to determine the fraction of aliphatic carbon in astronomical sources. In reality, each of the transitions previously utilized for such an attribution is highly mixed with contributions from both aliphatic and aromatic CH motions as well as non-CH motions such as CC stretches. High-resolution gas-phase IR absorption measurements of the spectra of …