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Full-Text Articles in Physical Sciences and Mathematics

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 …


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 …


Weird Winter Weather In The Anthropocene: How Volatile Temperatures Shape Violent Crime, Christopher Thomas, Kevin T. Wolff Jun 2023

Weird Winter Weather In The Anthropocene: How Volatile Temperatures Shape Violent Crime, Christopher Thomas, Kevin T. Wolff

Publications and Research

Purpose: Current evidence suggests volatile temperatures are becoming more common because of climate change and can be expected to become even more frequent in the future. By focusing on recent temperature variability, we attempt to estimate one important dimension of the impact of climate change on violent crime. We also explore whether sudden upward temperature anomalies have stronger positive impacts on violent crime in the coldest months of the year, as routine activities are likely to change more drastically during this period.

Methods: This study explores the association between sudden temperature anomalies (both upward and downward) and the daily incidence …


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) …


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 …


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, …


Accelerating Parameter Identifiability Of Differential Models With Applications To Parameter Estimation, Ilia Ilmer Jun 2023

Accelerating Parameter Identifiability Of Differential Models With Applications To Parameter Estimation, Ilia Ilmer

Dissertations, Theses, and Capstone Projects

The task of mathematical modeling involves working with real world phenomena described via parametric ordinary differential equations (ODE). Typically, an ODE model consists of states, parameters, inputs, and outputs. The states represent quantities whose dynamics the model describes, the parameters are quantities that are specific to the phenomenon being studied. Finally, inputs and outputs represent functions that are being added and measured from experiments, respectively. One of the questions that arises in studies of such models, is whether for given input-output setup one can efficiently and correctly estimate the values of parameters or initial conditions. This property of parameters or …


Performance Modeling For Network Anomaly Detection And Sensor Networks, Jie Chu Jun 2023

Performance Modeling For Network Anomaly Detection And Sensor Networks, Jie Chu

Dissertations, Theses, and Capstone Projects

Computer networks have become one of the fundamental communication infrastructures of the modern world. Data collection and data analysis over computer networks is a broad area of research and is getting more and more complicated as the ever-increasing complexity of the computer networks. In this dissertation, I will conduct performance modeling work for a few network scenarios and applications. In the first part of this dissertation, I will focus on two vital perspectives of the Internet, one from network administrators and the other from network users. Network administrators are key to manage and protect a computer network. I will study …


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.


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 …


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, …


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 …


Transformation And Abstraction To Aid Comparison Of Binary Executables Across Compilation Environments, Jeremy D. Seideman Jun 2023

Transformation And Abstraction To Aid Comparison Of Binary Executables Across Compilation Environments, Jeremy D. Seideman

Dissertations, Theses, and Capstone Projects

Binary analysis allows researchers to examine how programs are constructed and how they will impact an underlying system. The various analysis techniques allow the determination of code authorship, reuse, and similarity. Detecting code reuse is significant because code reuse can be a method for vulnerabilities and security issues to spread among software projects. In this work, we examine techniques that can aid in binary analysis, especially those that abstract and transform binaries, so that they can be compared across compilation environments, including possible changes in compiler version, hardware architecture, and compilation options. Historically, this has been difficult to accomplish since …


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 …


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 …


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 …


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 …


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 …


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 …


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 …


Artificial Intelligence In Neuroradiology: A Scoping Review Of Some Ethical Challenges, Pegah Khosravi, Mark Schweitzer May 2023

Artificial Intelligence In Neuroradiology: A Scoping Review Of Some Ethical Challenges, Pegah Khosravi, Mark Schweitzer

Publications and Research

Artificial intelligence (AI) has great potential to increase accuracy and efficiency in many aspects of neuroradiology. It provides substantial opportunities for insights into brain pathophysiology, developing models to determine treatment decisions, and improving current prognostication as well as diagnostic algorithms. Concurrently, the autonomous use of AI models introduces ethical challenges regarding the scope of informed consent, risks associated with data privacy and protection, potential database biases, as well as responsibility and liability that might potentially arise. In this manuscript, we will first provide a brief overview of AI methods used in neuroradiology and segue into key methodological and ethical challenges. …


Understanding Data Mining And Its Relation To Information Systems, Malak Alammari May 2023

Understanding Data Mining And Its Relation To Information Systems, Malak Alammari

Publications and Research

This research project aims to enrich an Open Educational Resource (OER) textbook on Introduction to Information Systems/Technology with a focus on data mining and its relation to hardware and software components of information systems. The study will address the following research questions: (1) What is data mining? and (2) How does data relate to the hardware and software components of information systems? To answer these questions, the researcher will conduct research to ascertain the current state of data mining and its relevance in the field of information systems/technology. The results of the research will be incorporated into an existing OER …


Augmented & Virtual Reality: Advancement Of Technology And Its Impacts On Medicine, Education, And Other Industries, Yassine Chahid May 2023

Augmented & Virtual Reality: Advancement Of Technology And Its Impacts On Medicine, Education, And Other Industries, Yassine Chahid

Publications and Research

Throughout the early 2000s, the ways in which the World Wide Web was used would undergo major changes. The introduction of these changes around this time period would be collectively known as Web 2.0. With Web 2.0, accessibility and distribution of applications became more simplified. During the 2000s, much has evolved from hard capabilities to the internet and its widespread usage amongst companies and general consumers. In contemporary times, multiple technologies, both hardware and digital are becoming more advanced, with general consumers either rejecting or accepting these gradual shifts in what may become everyday technology. Web 3.0, the theoretical advancement …


Machine Learning In Finances, Elma Kastrat, Akinyemi Apampa, Satyanand Singh May 2023

Machine Learning In Finances, Elma Kastrat, Akinyemi Apampa, Satyanand Singh

Publications and Research

In our study we work on an optimization of an appropriate stock portfolio base on available information. Our work takes into consideration the average return and any associated risk. We produce an investment strategy that predictively allows a portfolio to grow with high yields.


Internet Programming, Kwame A. Baffour May 2023

Internet Programming, Kwame A. Baffour

Open Educational Resources

CSC 31800 – Internet Programming

The design and implementation of websites from a Human-Computer Interaction point of view. Covers client-side technologies such as HTML, CSS and JavaScript and server-side technologies including Node.js and relational databases. Responsiveness, inclusion and accessibility by persons with mobility and vision impairment is necessary and must be addressed in the final project.



Analyzing Real Life Scenarios Through Linear And Exponential Functions Using Open Pedagogy., Lili Grigorian May 2023

Analyzing Real Life Scenarios Through Linear And Exponential Functions Using Open Pedagogy., Lili Grigorian

Open Educational Resources

This assignment is on linear and exponential growth, which is connected to real life scenarios from students’ everyday life as well as teaches them financial responsibility and awareness of economic issues. Project has five parts. In part 1, students would use digital communication ability by creating a video about the topic from the knowledge they had prior to this project. In part 2 (the Mathematical part) they will use problem-solving and inquiry learning to better understand linear and exponential growth, in part 3 students will use global learning through reading to then annotate article and watch video to then discuss …


Mth 125 - Modeling With Exponential Functions, Stivi Manoku Apr 2023

Mth 125 - Modeling With Exponential Functions, Stivi Manoku

Open Educational Resources

The file includes a variety of problems that emphasize the importance of modeling exponential growth and/or radioactive decay. Through different exercises and problems, the assignment goal is to improve their comprehension of exponential functions and hone their problem-solving abilities.


The Compound Risk Of Heat And Covid-19 In New York City: Riskscapes, Physical And Social Factors, And Interventions, Janelle Knox-Hayes, Juan Camilo Osorio, Natasha Stamler, Maria Dombrov, Rose Winer, Mary Hannah Smith, Reginald Blake, Cynthia Rosenzweig Apr 2023

The Compound Risk Of Heat And Covid-19 In New York City: Riskscapes, Physical And Social Factors, And Interventions, Janelle Knox-Hayes, Juan Camilo Osorio, Natasha Stamler, Maria Dombrov, Rose Winer, Mary Hannah Smith, Reginald Blake, Cynthia Rosenzweig

Publications and Research

Climate change is disrupting the fundamental conditions of human life and exacerbating existing inequity by placing further burdens on communities that are already vulnerable. Risk exposure varies by where people live and work. In this article, we examine the spatial overlap of the compound risks of COVID-19 and extreme heat in New York City. We assess the relationship between socio-demographic and natural, built and social environmental characteristics, and the spatial correspondence of COVID-19 daily case rates across three pandemic waves. We use these data to create a compound risk index combining heat, COVID-19, density and social vulnerability. Our findings demonstrate …


Logic And Rationality, Rohit J. Parikh Apr 2023

Logic And Rationality, Rohit J. Parikh

Publications and Research

Logic aims at truth, or more accurately, at deriving some truths from other truths. But why are we interested in truth in the first place? Surely one reason is that relying on truth makes it easier to make better choices.

One could think of Game theory as a tool which bridges the gap between logic and rationality.

Decision theory - or single agent game theory tells us when to make the best choice in a game of us against nature. But nature has no desire to further or frustrate our efforts. Nature is mysterious but not malign. Things change when …


Number Theoretic Arithmetic Functions And Dirichlet Series, Ivan V. Morozov Apr 2023

Number Theoretic Arithmetic Functions And Dirichlet Series, Ivan V. Morozov

Publications and Research

In this study, we will study number theoretic functions and their associated Dirichlet series. This study lay the foundation for deep research that has applications in cryptography and theoretical studies. Our work will expand known results and venture into the complex plane.