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United Properties Of Single-Origin Chocolates, Joseph Cooney 2023 Utah State University

United Properties Of Single-Origin Chocolates, Joseph Cooney

Student Research Symposium

In small production facilities, such as those used to manufacture single origin chocolate, cocoa nibs are ground to reduce the particle size to levels below 20 microns. This is a very important step during chocolate production, since chocolates with particles greater than 20 microns will have a grainy texture and unacceptable mouthfeel. The objective of this research was to evaluate changes in viscosity during chocolate grinding as affected by chocolate formulation. Three different types of chocolates were evaluated: 70% dark, 50% milk, and a Swiss-style milk chocolate. Chocolates were processed in a stone grinder and samples were taken as a …


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 …


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 …


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

Developing Carbon Quantum Dots As Multimodal Contrast Agents, Nicholas Whiting

College of Science & Mathematics Departmental Research

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

College of Science & Mathematics Departmental Research

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 …


Dynamics In Designed Elastins And Enzymes, Jonathan M. Preston 2023 CUNY Graduate Center

Dynamics In Designed Elastins And Enzymes, Jonathan M. Preston

Dissertations, Theses, and Capstone Projects

In this dissertation I present experimental results on the structure and dynamics of elastin, an elastomeric extracellular component in vertebrates that, in mammals, provides structure and elasticity to the circulatory system, lungs, skin and joints. These experiments, using a set of designed elastin like proteins with properties analogous to the natural protein, show that elastin is highly disordered and connect this disorder to its mechanism of assembly and elasticity. In addition, I also present preliminary work on imparting flexibility into a set of computationally designed metalloenzymes to broaden the range of catalytic activities they perform.


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 …


The Clinical Transferability Of Raman Micro-Spectroscopic Systems For Cervical Cytopathology, Rubina Shaikh Dr, Sarah Loughlin, Alison Malkin, John J. O'Leary, Cara M. Martin, Fiona Lyng 2023 Technological University Dublin

The Clinical Transferability Of Raman Micro-Spectroscopic Systems For Cervical Cytopathology, Rubina Shaikh Dr, Sarah Loughlin, Alison Malkin, John J. O'Leary, Cara M. Martin, Fiona Lyng

Conference papers

The clinical potential for Raman microscopic systems is well established for early diagnosis via cytology. Although Raman systems offer a complementary diagnostic tool providing molecular information, it is not yet utilised substantially in clinics. A few challenges for the clinical implementation of Raman spectroscopy are system and user variability. In this study, we asked how much variability occurs due to different Raman systems or users. To address these questions, we measured the same set of cells using two different Raman microscopes and by two different users. And classification models were generated using multivariate partial least squares discriminant analysis (PLS-DA) and …


Long-Range And Chaotic Active Mixing Of Swimming Microbes In A Vortex Chain Flow, Nghia Le 2023 Bucknell University

Long-Range And Chaotic Active Mixing Of Swimming Microbes In A Vortex Chain Flow, Nghia Le

Honors Theses

We present experiments studying the motion and active mixing of swimming mi- crobes in laminar, vortex-dominated fluid flows. We are testing a theory that predicts the existence of swimming invariant manifolds (SwIMs) - invisible, one-way barriers blocking the paths of self-propelled tracers in the flow in one direction. We also pro- pose that the SwIMs together can form chute structures in three-dimensional phase space that facilitate cross-vortex transport of the microbes. We also observe evidence of how these structures promote long-range transport at different non-dimensional velocities (microbe’s velocity relative to flow velocity). Long-range transport is quan- tified by measuring the …


Fabrication And Investigation Of Microfluidic Devices That Produce Non-Linear Chemical Gradients, Elijah L. Waters 2023 Georgia Southern University

Fabrication And Investigation Of Microfluidic Devices That Produce Non-Linear Chemical Gradients, Elijah L. Waters

College of Graduate Studies: Theses & Dissertations

Investigation of cell chemotaxis requires controlled chemical gradients. We investigated microfluidic devices that could enhance small populations' cell assays because of their ability to generate various chemical gradients. Our five designs generate different chemical concentration landscapes that we can easily convert into tools to study cell response to growth factors. Gradient landscapes occurred by splitting and mixing two input fluid concentrations using bifurcations, trifurcations, and Y-mixing junctions in three consecutive steps. Such fluid flow manipulations resulted in nine concentration streams entering a 0.54-mm-wide gradient chamber. The first design used a 1:1 ratio Y-mixer (unbiased) when blending two concentrations, resulting in …


First Review Of Equilibrium Landscape Of Ingress/Egress Channels And Gating Residues Of The Cytochrome P450 3a4, Edward Ackad Ph.D, Maria Kontoyianni 2023 Southern Illinois University Edwardsville

First Review Of Equilibrium Landscape Of Ingress/Egress Channels And Gating Residues Of The Cytochrome P450 3a4, Edward Ackad Ph.D, Maria Kontoyianni

SIUE Faculty Research, Scholarship, and Creative Activity

The review document and changes made to "Equilibrium Landscape of Ingress/Egress Channels and Gating Residues of the Cytochrome P450 3A4".


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 …


Optical Tweezers: Exerting Force With Light, Gabriella Seifert 2023 Scripps College

Optical Tweezers: Exerting Force With Light, Gabriella Seifert

Scripps Senior Theses

Photons carry momentum. When a tightly-focused beam of photons hit a particle, they transfer some of their momentum to the particle, exerting a force. Optical tweezers take advantage of this phenomenon to trap (or “tweeze”) a spherical bead just after the focus of a diverging laser beam, creating a potential well that pulls in beads. In this thesis, I predict the force exerted on trapped beads and measure the actual force using an optical tweezers setup that I built. To predict the force, I follow the path of all possible rays from a diverging beam incident on a spherical bead …


Analysis Of Biologically Effective Dose For Retroactive Yttrium-90 Trans-Arterial Radioembolization Treatment Optimization, MJ Lindsey 2023 Claremont McKenna College

Analysis Of Biologically Effective Dose For Retroactive Yttrium-90 Trans-Arterial Radioembolization Treatment Optimization, Mj Lindsey

CMC Senior Theses

Trans-arterial radioembolization (TARE) is a protracted modality of radiation therapy where radionuclides labeled with Yttrium-90 (90Y) are inserted inside a patient's hepatic artery to treat hepatocellular carcinoma (HCC). While TARE has been shown to be a clinically effective and safe treatment, there is little understanding of the radiobiological relationship between absorbed dose and tissue response, and thus there is no dosimetric standard for treatment planning. The Biologically Effective Dose (BED) formalism, derived from the Linear-Quadratic model of radiobiology, is used to weigh the absorbed dose by the time pattern of delivery. BED is a virtual dose that can …


Review-Electrode Kinetics And Electrolyte Stability In Vanadium Flow Batteries, Andrea Bourke, Daniela Oboroceanu, Nathan Quill, Catherine Lenihan, Maria Alhajji Safi Maria Alhajji Safi, Mallory A. Miller, Robert F. Savinell, Jesse S. Wainright, Varsha SasikumarSP, Maria Rybalchenko, Pupak Amini, Niall Dalton, Robert P. Lynch, D. Noel Buckley 2023 Technological University of the Shannon, Ireland

Review-Electrode Kinetics And Electrolyte Stability In Vanadium Flow Batteries, Andrea Bourke, Daniela Oboroceanu, Nathan Quill, Catherine Lenihan, Maria Alhajji Safi Maria Alhajji Safi, Mallory A. Miller, Robert F. Savinell, Jesse S. Wainright, Varsha Sasikumarsp, Maria Rybalchenko, Pupak Amini, Niall Dalton, Robert P. Lynch, D. Noel Buckley

Articles

Two aspects of vanadium flow batteries are reviewed: electrochemical kinetics on carbon electrodes and positive electrolyte stability. There is poor agreement between reported values of kinetic parameters; however, most authors report that kinetic rates are faster for VIV/VV than for VII/VIII. Cycling the electrode potential increases the rates of both reactions initially due to roughening but when no further roughening is observed, the VII/VIII and VIV/VV reactions are affected oppositely by the pretreatment potential. Anodic pretreatment activates the electrode for the VII/VIII reaction, and deactivates it for VIV/VV. Three states of the carbon surface are suggested: reduced and oxidized states …


Behaviors For Which Deinonychosaurs Used Their Feet, Alexander King 2022 Bowling Green State University

Behaviors For Which Deinonychosaurs Used Their Feet, Alexander King

Honors Projects

This paper seeks to show for what purpose deinonychosaurs used their feet. Fowler et al., (2011) showed that D. antirrhopus’s feet were closest in function to accipitrids, as they found it was more built for grasping prey than running.

I answered this question by using 2D images of the feet of three modern birds (Buteo jamaicensis, Phasianus colchicus, and Gallus gallus domesticus), one eudromaeosaur (Deinonychus antirrhopus), and one troodontid (Borogovia gracilicrus). I used ImageJ to apply 73 landmarks to each foot, capturing the variation between species in the metatarsals and pedal phalanges. These data were then uploaded to the software …


Cell Division Dynamics Of Escherichia Coli In Extreme Environments, Steven P. Murray 2022 University of Arkansas, Fayetteville

Cell Division Dynamics Of Escherichia Coli In Extreme Environments, Steven P. Murray

Graduate Theses and Dissertations

Life is remarkable in how resilient it can be. Many organism, classified as ex- tremophiles, can not only survive in extreme environments, but they can thrive in them. In the search for extraterrestrial life, the best candidates to harbor life exist with some kind of extreme condition. Europa, for example, is a favorite for the possibility of accommodating life as we know it within our solar system. Thought there is believed to be a liquid ocean under its icy surface, this habitat would be under immense pressures and high salinity. To best know where to look for extraterrestrial life, it …


Fluid-Structure Interaction Modelling Of Neighboring Tubes With Primary Cilium Analysis, Nerion Zekaj, Shawn D. Ryan, Andrew Resnick 2022 University of North Carolina at Chapel Hill

Fluid-Structure Interaction Modelling Of Neighboring Tubes With Primary Cilium Analysis, Nerion Zekaj, Shawn D. Ryan, Andrew Resnick

Mathematics and Statistics Faculty Publications

We have developed a numerical model of two osculating cylindrical elastic renal tubules to investigate the impact of neighboring tubules on the stress applied to a primary cilium. We hypothesize that the stress at the base of the primary cilium will depend on the mechanical coupling of the tubules due to local constrained motion of the tubule wall. The objective of this work was to determine the in-plane stresses of a primary cilium attached to the inner wall of one renal tubule subject to the applied pulsatile flow, with a neighboring renal tube filled with stagnant fluid in close proximity …


A Method For Exploring The Habitability Of Earth-Like Exoplanets: Applications To Tess Objects Of Interest 203 B, 256 B, And 700 D, Paul Bonney 2022 University of Arkansas, Fayetteville

A Method For Exploring The Habitability Of Earth-Like Exoplanets: Applications To Tess Objects Of Interest 203 B, 256 B, And 700 D, Paul Bonney

Graduate Theses and Dissertations

The Transiting Exoplanet Survey Satellite (TESS) has and is continuing to discover a multitude of potentially habitable planet candidates. As more planets are detected and confirmed, it becomes increasingly important to strategically search for signs of habitability with which to differentiate and prioritize them for further observation, in particular with the James Webb Space Telescope (JWST). To facilitate this, I have created a method for prioritizing TESS planet candidates based on parameters derived from their light curves and have applied the method to the TESS Candidate Target List (CTL). This data set uses preliminary fits to transit modeling which can …


Photoionization Energetics And Dissociation Pathways Of Hydroperoxyethyl Formate Produced In The Reaction Of Ch3Choo + Formic Acid, Vincent J. Esposito, Trent A. McHenry, Marsha I. Lester 2022 Chapman University

Photoionization Energetics And Dissociation Pathways Of Hydroperoxyethyl Formate Produced In The Reaction Of Ch3Choo + Formic Acid, Vincent J. Esposito, Trent A. Mchenry, Marsha I. Lester

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The bimolecular reaction of Criegee intermediates, zwitterionic carbonyl oxide species produced in alkene ozonolysis, with organic acids leads to formation of functional hydroperoxides implicated in the generation of atmospheric aerosols. This theoretical study using high-level explicitly correlated coupled-cluster theory examines the low energy conformers of hydroperoxyethyl formate [HOOCH(CH3)OCHO, HPEF] formed in the bimolecular reaction of CH3CHOO, a simple alkyl-substituted Criegee intermediate, with formic acid, and the detection of HPEF via photoionization. The vertical and adiabatic ionization energies of HPEF are computed, along with the pathways for dissociative ionization that produce HO2 or OCHO fragments with …


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