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Full-Text Articles in Physical Sciences and Mathematics

Identification Of Different Hair Dyes In Dyed Hair Using Attenuated Total Reflectance (Atr Ft-Ir), Surface Enhancing Raman Spectroscopy (Sers) Techniques, Nicholas Lovera Jun 2023

Identification Of Different Hair Dyes In Dyed Hair Using Attenuated Total Reflectance (Atr Ft-Ir), Surface Enhancing Raman Spectroscopy (Sers) Techniques, Nicholas Lovera

Student Theses

This investigation compares the ability of Attenuated Total Reflection Fourier Transfer Infrared Spectroscopy (ATR FT-IR) and Surface Enhance Raman Spectroscopy (SERS) to identify and differentiate different hair dye brands on dyed hair samples. Hair is a common type of trace evidence found at crime scenes and can provide numerous information through forensic hair analysis. Cosmetic hair treatment such as dying the hair different colors has grown and became popular, thus it can be a very common type of trace evidence. This study can provide a forensic scientist an additional method for analyzing dyed hair samples. The goal was to compare …


Pairings In A Ring Spectrum-Based Bousfield-Kan Spectral Sequence, Jonathan Toledo Jun 2023

Pairings In A Ring Spectrum-Based Bousfield-Kan Spectral Sequence, Jonathan Toledo

Dissertations, Theses, and Capstone Projects

Bousfield and Kan traditionally formulated their homotopy spectral sequence over a simplicial set X resolved with respect to a ring R. By considering an adequate category of ring spectra, one can take a ring spectrum E, create from it a functor of a triple on the category of simplicial sets, and build a cosimplicial simplicial set EX. The homotopy spectral sequence can then be formed over such cosimplicial spaces by a similar construction to the original. Pairings can be established on these spectral sequences, and, for nice enough spaces, these pairings on the E2-terms coincide with certain …


Sers For The Detection Of Trace Materials, Omari Kirkland Jun 2023

Sers For The Detection Of Trace Materials, Omari Kirkland

Dissertations, Theses, and Capstone Projects

In this dissertation are presented three projects that contribute to the body of research on SERS in the forensic, heritage, and semiconductor fields. The first project, Charge-Transfer mapping on GaN/Ag, a silver-decorated nanopillar semiconductor substrate fabricated from the GaN is used with the Raman probe Rhodamine 6 G (R6G) to map the effect of the nanofeatures on the CT resonance. The second project, in collaboration with Marco Leona from the Metropolitan Museum of Art, explores the use of AgNIFs to identify colorants used on textile fiber samples from four 19th century works of Japanese art. The final project analyzes the …


Design, Synthesis, And Kinetic Study Of The First Generation Phenyloxadiazole Compounds And The Second Generation Phenyloxadiazole Compounds And Highly Selective Hydroboration Of Alkenes, Ketones And Aldehydes Catalyzed By A Well-Defined Manganese Complex, Haisu Zeng Jun 2023

Design, Synthesis, And Kinetic Study Of The First Generation Phenyloxadiazole Compounds And The Second Generation Phenyloxadiazole Compounds And Highly Selective Hydroboration Of Alkenes, Ketones And Aldehydes Catalyzed By A Well-Defined Manganese Complex, Haisu Zeng

Dissertations, Theses, and Capstone Projects

This thesis focuses on two projects. In the first project, my goal was to discover a new variant of phenyloxadiazole compounds that could exhibit increased thiol-reactivity during bioconjugation processes. To achieve this, I synthesized several phenyloxadiazole derivatives and subjected them to NMR kinetic studies to assess their reactivity with a model thiol. Based on the results, I was able to identify a phenyloxadiazole analog that demonstrated enhanced reactivity, which included a chlorine atom located in the meta-position of the phenyl ring.

I provided a detailed description of the synthesis and characterization of the newly discovered phenyloxadiazole analog and demonstrate its …


Untangling The Nature And Timescales Of Magmatic Processes Driving Eruptions At Quiescent Volcanoes: Examples From Momotombo, Nicaragua, And Cumbre Vieja, Canary Islands, Samantha Tramontano Jun 2023

Untangling The Nature And Timescales Of Magmatic Processes Driving Eruptions At Quiescent Volcanoes: Examples From Momotombo, Nicaragua, And Cumbre Vieja, Canary Islands, Samantha Tramontano

Dissertations, Theses, and Capstone Projects

Across all scales of human relationships (i.e. person-to-person, country-to-country, etc.), qualms can take the form of long-standing wars, quick and intense bouts, or petty exchanges. While our understanding of human behavior is ever increasing, reactions and behaviors of self and others may still come as a surprise. Expressions of disagreement can occur suddenly or following years to centuries of accumulated grievances. The solid earth is also a system that behaves (like human emotion) predictably at times and unpredictably at other times. Some volcanoes, a tangible surface expression of solid earth processes, exhibit precursory signals prior to eruption (e.g. the bulging …


The Development Of Novel Radioimmunoconjugates For The Pet Imaging And Radioimmunotherapy Of Cancer, Samantha M. Sarrett Jun 2023

The Development Of Novel Radioimmunoconjugates For The Pet Imaging And Radioimmunotherapy Of Cancer, Samantha M. Sarrett

Dissertations, Theses, and Capstone Projects

Antibodies have long played a vital role in nuclear medicine for both the diagnosis and therapy of various malignancies. The role and development of antibodies in nuclear medicine can be broadly separated into three different categories: 1) bioconjugation strategies, 2) immunoPET imaging, and 3) radioimmunotherapy. This dissertation will attempt to comprehensively cover each of these categories through a series of studies, protocols, and reviews. For the bioconjugation strategies, we will describe the development of a novel site-selective bioconjugation strategy using an innovative lysine-targeting reagent, PFP-bisN3, to prepare [89Zr]Zr-SSKDFO-pertuzumab for visualizing HER2+ breast cancer. Further, …


Phantom Shootings, Allan Ambris Jun 2023

Phantom Shootings, Allan Ambris

Dissertations, Theses, and Capstone Projects

This capstone is a website designed to critique NYC Open Data reporting with respect to shootings through a series of visualizations and discoveries. The NYPD Shooting Incidents datasets (Historic and Year to Date) introduce themselves to the user by claiming to be a “list of every shooting incident that occurred in NYC.” The supplied documentation reveals that this is not the case.

After understanding the supporting materials, there are still undisclosed truths. My exploration of the data revealed that a single victim may be represented across multiple entries. Additionally, multiple victims may be represented by a single entry. It is …


Quantifying Separability In Limit Groups, Keino Brown Jun 2023

Quantifying Separability In Limit Groups, Keino Brown

Dissertations, Theses, and Capstone Projects

We show that for any finitely generated non-abelian subgroup H of a limit group L, there exists a finite-index subgroup K which is fully residually H. This generalizes the result of Wilton that limit groups admit local retractions. We also show that for any finitely generated subgroup of a limit group, there is a finite-dimensional representation of the limit group which separates the subgroup in the induced Zariski topology. As a corollary, we establish a polynomial upper bound on the size of the quotients used to separate a finitely generated subgroup in a limit group. This generalizes results of Louder, …


Statistical And Biological Analyses Of Acoustic Signals In Estrildid Finches, Moises Rivera Jun 2023

Statistical And Biological Analyses Of Acoustic Signals In Estrildid Finches, Moises Rivera

Dissertations, Theses, and Capstone Projects

Acoustic communication is a process that involves auditory perception and signal processing. Discrimination and recognition further require cognitive processes and supporting mechanisms in order to successfully identify and appropriately respond to signal senders. Although acoustic communication is common across birds, classical research has largely disregarded the perceptual abilities of perinatal altricial taxa. Chapter 1 reviews the literature of perinatal acoustic stimulation in birds, highlighting the disproportionate focus on precocial birds (e.g., chickens, ducks, quails). The long-held belief that altricial birds were incapable of acoustic perception in ovo was only recently overturned, as researchers began to find behavioral and physiological evidence …


Analysis Of Polymer-Coated Bullets Using Spectroscopic Methods, Liana R. Albano Jun 2023

Analysis Of Polymer-Coated Bullets Using Spectroscopic Methods, Liana R. Albano

Student Theses

Polymer-coated bullets have gained popularity because they can reduce the user’s exposure to heavy metals in the ammunition. The synthetic jacket, which surrounds the lead core, is advantageous because it prevents metal-on-metal contact between the bullet and the bore. A challenge for firearms identification is that polymer-coated bullets do not retain unique markings that can be used to identify the gun, the way standard metal-coated bullets do. However, metal-coated bullets will result in a similar challenge if the bullet is too deformed once it is recovered. Another issue is that the composition of the polymer coating was never disclosed by …


Evaluating Neural Networks As Cognitive Models For Learning Quasi-Regularities In Language, Xiaomeng Ma Jun 2023

Evaluating Neural Networks As Cognitive Models For Learning Quasi-Regularities In Language, Xiaomeng Ma

Dissertations, Theses, and Capstone Projects

Many aspects of language can be categorized as quasi-regular: the relationship between the inputs and outputs is systematic but allows many exceptions. Common domains that contain quasi-regularity include morphological inflection and grapheme-phoneme mapping. How humans process quasi-regularity has been debated for decades. This thesis implemented modern neural network models, transformer models, on two tasks: English past tense inflection and Chinese character naming, to investigate how transformer models perform quasi-regularity tasks. This thesis focuses on investigating to what extent the models' performances can represent human behavior. The results show that the transformers' performance is very similar to human behavior in many …


Hydrodynamic And Physicochemical Interactions Between An Active Janus Particle And An Inactive Particle, Jessica S. Rosenberg Jun 2023

Hydrodynamic And Physicochemical Interactions Between An Active Janus Particle And An Inactive Particle, Jessica S. Rosenberg

Dissertations, Theses, and Capstone Projects

Active matter is an area of soft matter science in which units consume energy and turn it into autonomous motion. Groups of these units – whether flocks of birds, bacterial colonies, or even collections of synthetically-made active particles – may exhibit complex behavior on large scales. While the large-scale picture is of great importance, so is the microscopic scale. Studying the individual particles that make up active matter will allow us to understand how they move, and whether and under what circumstances their activity can be controlled.

Here we delve into the world of active matter by studying colloidal-sized (100 …


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 Jun 2023

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 …


An Explicit Construction Of Sheaves In Context, Tyler A. Bryson Jun 2023

An Explicit Construction Of Sheaves In Context, Tyler A. Bryson

Dissertations, Theses, and Capstone Projects

This document details the body of theory necessary to explicitly construct sheaves of sets on a site together with the development of supporting material necessary to connect sheaf theory with the wider mathematical contexts in which it is applied. Of particular interest is a novel presentation of the plus construction suitable for direct application to a site without first passing to the generated grothendieck topology.


A Typological And Chemical Analysis Of Roman Oil Lamps From Poggio Del Molino, Brandon Tejo Jun 2023

A Typological And Chemical Analysis Of Roman Oil Lamps From Poggio Del Molino, Brandon Tejo

Dissertations, Theses, and Capstone Projects

Terracotta lamps, known to the Romans as lucernae, are small, handheld, often decorated objects which provided ancient people light. To modern researchers, they serve as tools for dating stratigraphy and iconographic studies. Beyond their immediately apparent aesthetic and symbolic value, the chemical compositions of the clay of these lamps reflect their origin. This study complements archaeological typologies with chemometric analyses to describe 16 Late Republican and Imperial Roman lamps recovered from the villa at Poggio del Molino (PdM), Tuscany. These finds were recovered from the 2021 and 2022 PdM excavations. The combined approach of typology with X-ray Diffraction (XRD) …


The Study Of Excitons In 2d Novel Materials And Their Van Der Waals Heterostructures In The Magnetic Field, Anastasia Spiridonova Jun 2023

The Study Of Excitons In 2d Novel Materials And Their Van Der Waals Heterostructures In The Magnetic Field, Anastasia Spiridonova

Dissertations, Theses, and Capstone Projects

This research focuses on the direct and indirect excitons in Rydberg states in monolayers, bilayers, and van der Waals heterostructures composed of 2D semiconductors in the presence of the external magnetic field. In our work, we report binding energies of direct and indirect excitons in Rydberg states, the energy contribution from the magnetic field to the binding energies of magnetoexcitons, and diamagnetic coefficients (DMCs) of magnetoexcitons.

We study isotropic materials: transition metal dichalcogenides, TMDCs (WSe2, WS2, MoSe2, MoS2), and Xenes (silicene, germanene, stanene), and anisotropic materials: phosphorene and transition metal trichalcogenides, TMTCs …


Synthesis And Biomedical Applications Of Hollow Iron Oxide Nanoparticles, Aloka S. Paragoda Arachchilage Feb 2023

Synthesis And Biomedical Applications Of Hollow Iron Oxide Nanoparticles, Aloka S. Paragoda Arachchilage

Dissertations, Theses, and Capstone Projects

Nano-scale materials have gained much attention during the past few decades due to the stark differences in their properties compared to bulk material. Thus, they are being studied for a myriad of applications ranging from harnessing solar energy to diagnostics. This thesis focuses on the synthesis of hollow iron oxide nanoparticles using Galvanic replacement reactions and their application in drug delivery. Moreover, the use of a peptide precursor for the enhancement of exosomes is also discussed.

Chapter 1 discusses a simple and economical Galvanic approach used for the synthesis of hollow one-dimensional iron oxide nanotubes. In the initial reaction, the …


Nanoscale Imaging Of Electrocatalytic Nanomaterials By High-Resolution Scanning Electrochemical Microscopy, Xiang Wang Feb 2023

Nanoscale Imaging Of Electrocatalytic Nanomaterials By High-Resolution Scanning Electrochemical Microscopy, Xiang Wang

Dissertations, Theses, and Capstone Projects

Numerous insights of the structure–electrochemical activity relationship of nanocatalysts have been obtained by using macroscopic electrochemical measurements over the last several decades. However, signals measured by large electrodes are inevitably averaged out of many nanocatalysts, non-uniformed sizes, uneven morphologies, and multiple crystallographic facets. Over the last ten years, Scanning Electrochemical Microscopy (SECM) has advanced electrochemical measurements toward micro- to nanoscale level at a high spatial resolution. The advantages of using nanoelectrode in SECM include fast mass transfer of reactive species, dominated radial diffusion pattern, small double layer capacitance and small RC constant. In this thesis, high-resolution SECM is applied to …


Analyzing Relationships With Machine Learning, Oscar Ko Feb 2023

Analyzing Relationships With Machine Learning, Oscar Ko

Dissertations, Theses, and Capstone Projects

Procedurally, this project aims to take a dataset, analyze it, and offer insights to the audience in an easy-to-digest format. Conceptually, this project will seek to explore questions like: “Do couples that meet through online dating or dating apps have higher or lower quality relationships?”, “Can any features in this dataset help predict how a subject would rate their relationship quality?”, and “What other insights can I derive from using machine learning for exploratory analysis?” The intended audience for this project is anyone interested in romantic relationships or machine learning.

The dataset is from a Stanford University survey, “How Couples …


Revealing The Three-Dimensional Magnetic Texture With Machine Learning Models, Shihua Zhao Feb 2023

Revealing The Three-Dimensional Magnetic Texture With Machine Learning Models, Shihua Zhao

Dissertations, Theses, and Capstone Projects

Revealing three-dimensional (3D) magnetic textures with vector field electron tomography (VFET) is essential in studying novel magnetic materials with topologically protected spin textures potentially being used in the next-generation semiconductor industry. In this dissertation, we use machine learning (ML) models to reconstruct 3D magnetic textures from electron holography (EH) data.

We can feed the EH data, a series of two-dimensional (2D) phasemaps, into a neural network (NN) architecture directly or feed the EH data into a conventional VFET and then feed the reconstructed results into a NN. Thus, perceptive NN, either a simple convolutional neural network (CNN) or Unet architecture, …


Dynamics In Designed Elastins And Enzymes, Jonathan M. Preston Feb 2023

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.


Synthesis And Analysis Of Novel Troponoid-Based Chemical Probes, Alex Berkowitz Feb 2023

Synthesis And Analysis Of Novel Troponoid-Based Chemical Probes, Alex Berkowitz

Dissertations, Theses, and Capstone Projects

Troponoids are a class of non-benzenoid aromatic species featuring a cycloheptatrienone ring and varying degrees of oxygenation. These scaffolds have proven ubiquitous amongst natural products, and have displayed promise as therapeutic agents against a variety of diseases. Herein, we will describe our efforts towards furthering troponoids as potential pharmaceuticals. In Chapter 1, we outline a kojic acid-derived oxidopyrylium cycloaddition/ring-opening method developed in our lab to generate ahydroxytropolones (aHTs). This route was successfully adapted to synthesize a small library of lipophilic aHTs that were proven to be effective against herpes simplex virus-1 (HSV-1) replication, while providing further insight into the mechanism …


Optimized Peptide Nanomaterials As Delivery Vehicles For Hydrophobic Metal-Based Anticancer Agents, Yaron Marciano Feb 2023

Optimized Peptide Nanomaterials As Delivery Vehicles For Hydrophobic Metal-Based Anticancer Agents, Yaron Marciano

Dissertations, Theses, and Capstone Projects

Enzyme-responsive materials have been well explored, particularly as therapeutic and diagnostic agents. In this thesis we demonstrate that anionic self-assembling peptides can be utilized as delivery vehicles for metal-based hydrophobic payloads. The tunability of the system is highlighted as well as the increase in cytotoxicity and selectivity in vitro. The rapid degradation of peptides in cell media may lead to the formation of new peptide-drug bioconjugates with increased activity and selectivity. The physiological stability of these peptide delivery vehicles has been optimized by capping the N-terminus with an acetyl group. This simple backbone modification was shown to not prevent self-assembly, …


Unlocking Potential: The School-To-Prison Pipeline For Students With Disabilities, Navena F. Chaitoo Feb 2023

Unlocking Potential: The School-To-Prison Pipeline For Students With Disabilities, Navena F. Chaitoo

Dissertations, Theses, and Capstone Projects

This research uses quasi-experimental, matched sampling to examine the school-to-prison pipeline for students with disabilities using data from the National Longitudinal Study of Adolescent to Adult Health. This study presents novel insights into an at-risk group that has faced disproportionate rates of school discipline and incarceration. The study finds school suspension to be associated with future involvement in the criminal legal system and lower educational attainment. Disability was not found to mediate the relationship between suspension and future involvement in the criminal legal system or the relationship between suspension and academic outcomes. However, disability was found to be a statistically …


A Stronger Strong Schottky Lemma For Euclidean Buildings, Michael E. Ferguson Feb 2023

A Stronger Strong Schottky Lemma For Euclidean Buildings, Michael E. Ferguson

Dissertations, Theses, and Capstone Projects

We provide a criterion for two hyperbolic isometries of a Euclidean building to generate a free group of rank two. In particular, we extend the application of a Strong Schottky Lemma to buildings given by Alperin, Farb and Noskov. We then use this extension to obtain an infinite family of matrices that generate a free group of rank two. In doing so, we also introduce an algorithm that terminates in finite time if the lemma is applicable for pairs of certain kinds of matrices acting on the Euclidean building for the special linear group over certain discretely valued fields.


One-Loop Corrections To Dihadron Production In Dis At Small X, Filip Bergabo Feb 2023

One-Loop Corrections To Dihadron Production In Dis At Small X, Filip Bergabo

Dissertations, Theses, and Capstone Projects

We calculate the one-loop corrections to dihadron production in Deep Inelastic Scattering (DIS) at small x using the Color Glass Condensate formalism. We show that all UV and soft singularities cancel while the collinear divergences are absorbed into quark and anti quark-hadron fragmentation functions. Rapidity divergences lead to JIMWLK evolution of dipoles and quadrupoles describing multiple-scatterings of the quark anti-quark dipole on the target proton/nucleus. The resulting cross section is finite and can be used for phenomenological studies of dihadron angular correlations at small x in a future Electron-Ion Collider (EIC).


Naming Venus: An Exploration Of Goddesses, Heroines, And Famous Women, Kavya Beheraj Feb 2023

Naming Venus: An Exploration Of Goddesses, Heroines, And Famous Women, Kavya Beheraj

Dissertations, Theses, and Capstone Projects

Humans have been observing and romanticizing Venus for more than 5,000 years. However, mapping its surface has nearly always been impossible, since the planet is shrouded in thick clouds. A breakthrough came just fifty years ago with the invention of radar imaging, leading to the discovery (and naming) of hundreds of new features in a relatively short length of time.

The rapid naming of Venus is a case study on the impact of planetary nomenclature — the process of naming features on other worlds. While the act of naming streamlines communication and humanizes alien landscapes, it is subject to bias, …


A Quantum Approach To Language Modeling, Constantijn Van Der Poel Feb 2023

A Quantum Approach To Language Modeling, Constantijn Van Der Poel

Dissertations, Theses, and Capstone Projects

This dissertation consists of six chapters. . . Chapter 1: We introduce language modeling, outline the software used for this thesis, and discuss related work. Chapter 2: We will unpack the transition from classical to quantum probabilities, as well as motivate their use in building a model to understand language-like datasets. Chapter 3: We motivate the Motzkin dataset, the models we will be investigating, as well as the necessary algorithms to do calculations with them. Chapter 4: We investigate our models’ sensitivity to various hyperparameters. Chapter 5: We compare the performance and robustness of the models. Chapter 6: We conclude …


Social Impacts Of Robotics On The Labor And Employment Market, Kelvin Espinal Feb 2023

Social Impacts Of Robotics On The Labor And Employment Market, Kelvin Espinal

Dissertations, Theses, and Capstone Projects

Robotics have been introduced into the workplace to perform tasks that human beings have traditionally fulfilled. Complementing or substituting human labor with robotics eliminates human involvement in functions attributable to hazardous environments, heavy lifting, toxic substances, and repetitive low-level tasks. On the other hand, they are meant to be more efficient and cost-effective, saving money, time, and labor. However, since the introduction of robotics in the workforce, societal opposition has been towards this branch of technology in fear of losing employment, wages, and purpose.

Previous studies have reported an overarching societal fear that adopting robotics in the workplace and industry …


Beam-Based Target Alignment For Mu2e, Helenka Casler Feb 2023

Beam-Based Target Alignment For Mu2e, Helenka Casler

Dissertations, Theses, and Capstone Projects

The Mu2e Experiment is a precision experiment at Fermi National Accelerator Laboratory, searching for charged lepton flavor violation (CLFV) in the conversion of a muon to an electron in the presence of an atomic nucleus. In order to achieve the expected single-event sensitivity of 3 × 10-17 , Mu2e will require an intense muon beam, generated via pion decay. These pions are the product of a proton beam striking a radiatively-cooled tungsten target. In order to maximize pion production and prevent target failure, the beam will have to be aligned with the target center to within 0.5 mm. The …