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Raman Spectroscopic Analysis Of Human Serum Samples Of Convalescing Covid-19 Positive Patients, Hugh Byrne, Naomi Jackson, Jaythoon Hassan 2023 Technological University Dublin

Raman Spectroscopic Analysis Of Human Serum Samples Of Convalescing Covid-19 Positive Patients, Hugh Byrne, Naomi Jackson, Jaythoon Hassan

Articles

Rapid screening, detection and monitoring of viral infection is of critical importance, as exemplified by the rapid spread of SARS-CoV-2, leading to the worldwide pandemic of COVID-19. This is equally the case for the stages of patient convalescence as for the initial stages of infection, to understand the medium and long terms effects, as well as the efficacy of therapeutic interventions. Optical spectroscopic techniques potentially offer an alternative to currently employed techniques of screening for the presence, or the response to infection. In this study, the ability of Raman spectroscopy to distinguish between samples of the serum of convalescent COVID-19 …


Langevin Dynamic Models For Smfret Dynamic Shift, David Frost, Keisha Cook Dr, Hugo Sanabria Dr 2023 Clemson University

Langevin Dynamic Models For Smfret Dynamic Shift, David Frost, Keisha Cook Dr, Hugo Sanabria Dr

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


A Computational Kinetics Model To Quantify Radiation Induced Chemical Products Of Atmospheric Gas Mixtures, Patrick Ables 2023 The University of Southern Mississippi

A Computational Kinetics Model To Quantify Radiation Induced Chemical Products Of Atmospheric Gas Mixtures, Patrick Ables

Dissertations

This research is focused on the development of a computational model which will calculate the effects of radiation on the chemical composition of the atmosphere. The approach utilizes the open-source chemical kinetics toolkit Cantera to model the creation of radiation-induced reactant species within irradiated air mixtures. Chemical solutions are iteratively stepped toward chemical equilibrium within a ‘constantly stirred’ (homogeneous) reactor of fixed volume. Three different radiation chemistry models are implemented in several different pulsed and continuous radiation schemes. The first model includes the mechanisms and rates of a pulse radiation model from the literature to test the validity of the …


The Influence Of Allostery Governing The Changes In Protein Dynamics Upon Substitution, Joseph Hess 2023 Clemson University

The Influence Of Allostery Governing The Changes In Protein Dynamics Upon Substitution, Joseph Hess

All Dissertations

The focus of this research is to investigate the effects of allostery on the function/activity of an enzyme, human immunodeficiency virus type 1 (HIV-1) protease, using well-defined statistical analyses of the dynamic changes of the protein and variants with unique single point substitutions 1. The experimental data1 evaluated here only characterized HIV-1 protease with one of its potential target substrates. Probing the dynamic interactions of the residues of an enzyme and its variants can offer insight of the developmental importance for allosteric signaling and their connection to a protein’s function. The realignment of the secondary structure elements can …


Dinitrogen Functionalization Using A Molybdenum Atom: Bridging The Gap Between Small And Coordination Complexes Via Quantum Mechanical Methods, Maria Virginia White 2023 University of Tennessee, Knoxville

Dinitrogen Functionalization Using A Molybdenum Atom: Bridging The Gap Between Small And Coordination Complexes Via Quantum Mechanical Methods, Maria Virginia White

Doctoral Dissertations

Chemistry devotes a significant amount of its research to understanding small molecule activation from an electronic structure perspective to help with the investigation of the reaction pathways of catalytically active substances that can promote biomimetic catalysis. A large portion of the energy used annually in our planet is used for the artificial nitrogen fixation (Haber-Bosch process), which renders dinitrogen activation a subject of study. Molybdenum, a fourth row transitional metal, has demonstrated its effectiveness as an essential component of the dinitrogen reduction catalytic process. To better understand the multiple dinitrogen molybdenum binding modes, the work described herein combines wave function …


The Applicability Of The Postmortem Submersion Interval Estimation Formula For Human Remains Found In Subtropical Aquatic Environments, Kara L. DiComo 2023 University of South Florida

The Applicability Of The Postmortem Submersion Interval Estimation Formula For Human Remains Found In Subtropical Aquatic Environments, Kara L. Dicomo

USF Tampa Graduate Theses and Dissertations

Within the past decade, several attempts have been made to standardize a method for estimating postmortem submersion intervals (PMSI); however, the majority of these studies have focused on data from a temperate climate which cannot be taken as representative of large portions of the globe. Thus, there are large portions of the earth in which the methodology from these studies may not be able to accurately estimate PMSI which has the potential to leave investigators in these other climatic zones at a disadvantage. This presentation presents a case study into the applicability of two Total Body Scoring Systems (TADS) utilized …


Optimization Of Flagellar Locomotion In The Low Reynolds Number Regime, Aidan M. Trodden, Aidan M. Trodden 2023 California Polytechnic State University, San Luis Obispo

Optimization Of Flagellar Locomotion In The Low Reynolds Number Regime, Aidan M. Trodden, Aidan M. Trodden

Physics

This report investigates the computational and theoretical techniques - modeled by E. Lauga and C. Eloy - used to optimize the shape of an activated flagellum for enhanced cell motility. Cell motility is ubiquitous and has a large affect on biological systems such as marine life ecosystems, reproduction, and infection. The physical principles governing flagellar propulsion are explored using computational fluid dynamics simulations, mathematical modeling, and the sequential quadratic programming (SQP) optimization algorithm. Through iterative refinement, we can identify optimized flagellar shapes that would minimize the energetic cost dependent on a single dimensionless sperm numbers (Sp). The computation of the …


Characterization Of Boreal-Arctic Vegetation Growth Phases And Active Soil Layer Dynamics In The High-Latitudes Of North America: A Study Combining Multi-Year In Situ And Satellite-Based Observations, Michael G. Brown 2023 The Graduate Center, City University of New York

Characterization Of Boreal-Arctic Vegetation Growth Phases And Active Soil Layer Dynamics In The High-Latitudes Of North America: A Study Combining Multi-Year In Situ And Satellite-Based Observations, Michael G. Brown

Dissertations, Theses, and Capstone Projects

This dissertation examined the seasonal freeze/thaw activity in boreal-Arctic soils and vegetation physiology in Alaska, USA and Alberta, Canada, using in situ environmental measurements and passive microwave satellite observations. The boreal-Arctic high-latitudes have been experiencing ecosystem changes more rapidly in comparison to the rest of Earth due to the presently warming climatic conditions having a magnified effect over Polar Regions. Currently, the boreal-Arctic is a carbon sink; however, recent studies indicate a shift over the next century to become a carbon source. High-latitude vegetation and cold soil dynamics are influenced by climatic shifts and are largely responsible for the regions …


Flash-Rt: Using High-Dose Radiation For Clinical Radiation Therapy, Deja Stubbs 2023 Portland State University

Flash-Rt: Using High-Dose Radiation For Clinical Radiation Therapy, Deja Stubbs

University Honors Theses

This paper is a literature review on the possible mechanisms behind the FLASH effect and why such research can advance the world of radiology treatment by modifying current clinical linear accelerators to produce ultra-high doses of radiation. Radiation Therapy, also known as external Beam Radiation Therapy, is a common type of cancer treatment. Globally, cancer is the second-leading cause of death, but has seen an increase in survival rates over the past couple of years. Cancer can develop in almost any part of the body since cancer is defined as uncontrolled cell growth. The FLASH Effect is seen when treating …


Modeling Accuracy Matters: Aligning Molecular Dynamics With 2d Nmr Derived Noe Restraints, Milan Patel 2023 University of Connecticut

Modeling Accuracy Matters: Aligning Molecular Dynamics With 2d Nmr Derived Noe Restraints, Milan Patel

Honors Scholar Theses

Among structural biology techniques, Nuclear Magnetic Resonance (NMR) provides a holistic view of structure that is close to protein structure in situ. Namely, NMR imaging allows for the solution state of the protein to be observed, derived from Nuclear Overhauser Effect restraints (NOEs). NOEs are a distance range in which hydrogen pairs are observed to stay within range of, and therefore experimental data which computational models can be compared against. To that end, we investigated the effects of adding the NOE restraints as distance restraints in Molecular Dynamics (MD) simulations on the 24 residue HP24stab derived villin headpiece subdomain to …


An Investigation On The Effect Of Conserved Hinge Histidine On Influenza Hemagglutinin(Ha2) Protein Conformation Using Md Simulations, Nada Tolba 2023 University of Arkansas, Fayetteville

An Investigation On The Effect Of Conserved Hinge Histidine On Influenza Hemagglutinin(Ha2) Protein Conformation Using Md Simulations, Nada Tolba

Chemistry & Biochemistry Undergraduate Honors Theses

Hemagglutinin is a protein on the surface of Human Influenza Viruses.1 It is composed of two glycopolypeptide domains, the HA1 and HA2 domains. Previous studies have found that across different strains of Influenza viruses, HIS435 residues remain conserved.4 In studies where mutations occurred in hinge-site histadine residues, the Influenza virus was inactive.4 These investigations indicated a significant role of HIS435 (hinge-site histadines) in virulence. Four systems were created using Molecular dynamics (MD) simulations. Each system was composed of an Isolated HA2 trimer solvated in a 150 mM NaCl rectangular water box at 310 K under isobaric and …


Modelling Cell Population Growth, Mahmood Mazarei 2023 The University of Western Ontario

Modelling Cell Population Growth, Mahmood Mazarei

Electronic Thesis and Dissertation Repository

The growth of biological matter, e.g., tumor invasion, depends on various factors, mainly the tissue’s mechanical properties, implying elasticity, stiffness, or apparent viscosity. These properties are impacted by the characteristics of the tissue’s extracellular matrix and constituent cells, including, but not limited to, cell membrane stiffness, cell cytoskeleton mechanical properties, and the intensity and distribution of focal adhesions over the cell membrane. To compute and study the mechanical properties of tissues during growth and confluency, a theoretical and computational framework, called CellSim3D, was developed in our group based on a three-dimensional kinetic division model.

In this work, CellSim3D is …


An Ab Initio Computation Of The Potential Energy Surfaces Of The Dna Bases, Anjali F. Filinovich, Vola Andrianarijaona 2023 Southern Adventist University

An Ab Initio Computation Of The Potential Energy Surfaces Of The Dna Bases, Anjali F. Filinovich, Vola Andrianarijaona

Campus Research Day

The potential energy surfaces of atoms in DNA can be analyzed and compared to show how their bonds break. This DNA potential energy reference data is very useful to understanding how DNA damage occurs, however, a dataset of relevant potential energy surfaces is not available for scientific use. We obtain the potential energy surfaces of various atoms in the four DNA bases adenine, thymine, guanine, and cytosine, by moving an atom in these molecules in three orthogonal directions using ORCA, an ab initio quantum chemistry software. Density functional theory is
used to compute potential energies as an atom is moved, …


Analysis And Methodology Of Helical And Flexible Homopolymer Monte Carlo Simulations, Nathan Roberts 2023 Murray State University

Analysis And Methodology Of Helical And Flexible Homopolymer Monte Carlo Simulations, Nathan Roberts

Honors College Theses

The purpose of my work is to analyze the results of Monte Carlo simulations of various types of polymers: a helical homopolymer and a flexible homopolymer. Specific applications of Monte Carlo polymer simulations and parallel tempering replica exchanges are presented. Using temporal analysis, I aim to measure the efficiency of each type of simulation as it relates to equilibration time. For the helical homopolymer model, equilibration time is expanded upon to analyze the rate of structure generation and relevant hyper-phase diagram. Stable states for helical homopolymers will use data generated from parallel tempering replica exchange Monte Carlo simulations created by …


Novel As-S-Se Compositions Of Solution-Processed Chalcogenide Thin Films For Infrared Optics, Annabella Orsini 2023 Ursinus College

Novel As-S-Se Compositions Of Solution-Processed Chalcogenide Thin Films For Infrared Optics, Annabella Orsini

Physics and Astronomy Honors Papers

Chalcogenide glasses (ChGs) have a wide range of interdisciplinary applications. In industry, ChGs are used to vastly improve infrared sight abilities. There are, however, improvements that can be made to the films’ stability, cost, and flexibility. Our project seeks to produce thin films that have these improvements, with capabilities comparable or better than what is widely used in the field. Thin films created through solution-based processes have proven to be much more flexible in comparison to bulk glass versions. Other elements in Group 16, such as Sulfur and Selenium have shown across literature to be a cost-effective alternative to Tellurium …


Modeling Excited State Processes In Molecular Aggregates By Constructing An Adaptive Basis For The Hierarchy Of Pure States, Leonel Varvelo 2023 Southern Methodist University

Modeling Excited State Processes In Molecular Aggregates By Constructing An Adaptive Basis For The Hierarchy Of Pure States, Leonel Varvelo

Chemistry Theses and Dissertations

Simulating excitation energy transfer (EET) in molecular materials is of crucial importance for the development of and understanding of materials such as organic photovoltaics and photosynthetic systems and further development of novel materials. The Hierarchy of Pure States (HOPS) is an exact framework for the time evolution of an open quantum system in which a hierarchy of stochastic wave functions are propagated in time. The adaptive HOPS (adHOPS) method achieves size-invariant scaling with the number of simulated molecules for sufficiently large aggregates by using an adaptive basis that moves with the excitation through the material. To demonstrate the power of …


Developing Carbon Quantum Dots As Multimodal Contrast Agents, Nicholas Whiting 2023 Rowan University

Developing Carbon Quantum Dots As Multimodal Contrast Agents, Nicholas Whiting

Faculty Scholarship for the College of Science & Mathematics

No abstract provided.


Reconversion Of Parahydrogen Gas In Surfactant-Coated Glass Nmr Tubes, Robert V. Chimenti, James Daley, James Sack, Jennifer Necsutu, Nicholas Whiting 2023 Rowan University

Reconversion Of Parahydrogen Gas In Surfactant-Coated Glass Nmr Tubes, Robert V. Chimenti, James Daley, James Sack, Jennifer Necsutu, Nicholas Whiting

Faculty Scholarship for the College of Science & Mathematics

The application of parahydrogen gas to enhance the magnetic resonance signals of a diversity of chemical species has increased substantially in the last decade. Parahydrogen is prepared by lowering the temperature of hydrogen gas in the presence of a catalyst; this enriches the para spin isomer beyond its normal abundance of 25% at thermal equilibrium. Indeed, parahydrogen fractions that approach unity can be attained at sufficiently low temperatures. Once enriched, the gas will revert to its normal isomeric ratio over the course of hours or days, depending on the surface chemistry of the storage container. Although parahydrogen enjoys long lifetimes …


Minimal Expression Of Dysferlin Prevents Development Of Dysferlinopathy In Dysferlin Exon 40a Knockout Mice, Joe Yasa, Claudia E. Reed, Adam M. Bournazos, Frances J. Evesson, Ignatius Pang, Mark E. Graham, Jesse R. Wark, Brunda Nijagal, Kim H. Kwan, Thomas Kwiatkowski, Rachel Jung, Noah Weisleder, Sandra T. Cooper, Frances A. Lemckert 2023 The Children’s Hospital at Westmead, Sydney, Australia

Minimal Expression Of Dysferlin Prevents Development Of Dysferlinopathy In Dysferlin Exon 40a Knockout Mice, Joe Yasa, Claudia E. Reed, Adam M. Bournazos, Frances J. Evesson, Ignatius Pang, Mark E. Graham, Jesse R. Wark, Brunda Nijagal, Kim H. Kwan, Thomas Kwiatkowski, Rachel Jung, Noah Weisleder, Sandra T. Cooper, Frances A. Lemckert

Chemistry Faculty Publications

Dysferlin is a Ca2+-activated lipid binding protein implicated in muscle membrane repair. Recessive variants in DYSF result in dysferlinopathy, a progressive muscular dystrophy. We showed previously that calpain cleavage within a motif encoded by alternatively spliced exon 40a releases a 72 kDa C-terminal minidysferlin recruited to injured sarcolemma. Herein we use CRISPR/Cas9 gene editing to knock out murine Dysf exon 40a, to specifically assess its role in membrane repair and development of dysferlinopathy. We created three Dysf exon 40a knockout (40aKO) mouse lines that each express different levels of dysferlin protein ranging from similar to 90%, similar to 50% and …


Homopurine Guanine-Rich Sequences In Complex With N-Methyl Mesoporphyrin Ix Form Parallel G-Quadruplex Dimers And Display A Unique Symmetry Tetrad, Ming Ye, Erin V. Chen, Shawn H. Pfeil, Kailey N. Martin, Tamanaa Atrafi, Sara Yun, Zahara Martinez, Liliya A. Yatsunyk 2023 Swarthmore College

Homopurine Guanine-Rich Sequences In Complex With N-Methyl Mesoporphyrin Ix Form Parallel G-Quadruplex Dimers And Display A Unique Symmetry Tetrad, Ming Ye, Erin V. Chen, Shawn H. Pfeil, Kailey N. Martin, Tamanaa Atrafi, Sara Yun, Zahara Martinez, Liliya A. Yatsunyk

Physics & Engineering Faculty Publications

DNA can fold into G-quadruplexes (GQs), non-canonical secondary structures formed by pi-pi stacking of G-tet-rads. GQs are important in many biological processes, which makes them promising therapeutic targets. We identified a 42-nucleotide long, purine-only G-rich sequence from human genome, which contains eight G- stretches connected by A and AAAA loops. We divided this sequence into five unique segments, four guanine stretches each, named GA1-5. In order to investigate the role of adenines in GQ structure formation, we per-formed biophysical and X-ray crystallographic studies of GA1-5 and their complexes with a highly selective GQ ligand, N-methyl mesoporphyrin IX (NMM). Our data …


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