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City University of New York (CUNY)

Student Theses

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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 …


A Comparison Of Methods Used For The Elimination Of Organics From Soil Prior To Analysis By Ftir-Atr And Sem-Eds, Argeliz Pomales Aug 2022

A Comparison Of Methods Used For The Elimination Of Organics From Soil Prior To Analysis By Ftir-Atr And Sem-Eds, Argeliz Pomales

Student Theses

This project suggests improvements to the treatment methods utilized for the sample preparation and evaluation of minerals in soil samples encountered in forensic science casework and research. The evaluation of pre-treated and post-treated soil samples were performed using Fourier-Transform Infrared Spectroscopy with Attenuated Total Reflection (FTIR-ATR) and Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS). Because soil samples contain a significant amount of organic matter and water which interfere with examination of these minerals while using these instruments, pretreatment methods are necessary to isolate the mineral fraction for examination and analysis.

Soil samples were first sieved with various size stainless steel mesh …


Investigating The Mechanisms Driving Mercury Reduction And Emissions In Soil, Hamil Patel Jun 2022

Investigating The Mechanisms Driving Mercury Reduction And Emissions In Soil, Hamil Patel

Student Theses

The water-induced emission of mercury from soil has been studied, but a complete understanding of the mechanisms driving mercury reduction and emission in soil has not been reached. The current understanding is an immediate expulsion of soil gaseous mercury upon water treatment and an upward transport of dissolved soil ionic mercury as the water evaporates. We analyzed emissions from several types of samples using various methods to further our understanding on the mechanisms involved. Light-induced emissions from aqueous samples of humic acid (HA) spiked with mercury (II) chloride (HgCl2) showed that at higher concentrations of HA, less mercury …


Mapping The Covid-19 Pandemic In Staten Island, Vincenzo Mezzio May 2022

Mapping The Covid-19 Pandemic In Staten Island, Vincenzo Mezzio

Student Theses

COVID-19 has had diverging effects in New York City. Out of the five boroughs, Staten Island has one of the largest percentages of COVID-19 cases relative to population. This research examines key social and spatial factors that contribute to the increase in COVID-19 cases in Staten Island). It asks: Which parts of Staten Island have higher rates of transmission of COVID-19? Which parts of the borough have higher population who are more vulnerable to COVID-19? What is the relationship between the location of vaccination centers with the rates of COVID-19 cases? Using Geographic Information Systems (GIS), this research examines the …


Sorption Of Metals At The Barite (001)-Water Interface, Inva Braha Sep 2021

Sorption Of Metals At The Barite (001)-Water Interface, Inva Braha

Student Theses

Abstract

Ion desorption processes control the retention of ions, such as Pb2+, at barite surfaces, whereas ion adsorption processes are a likely initial step in the incorporation of divalent cations, such as Sr2+ and Pb2+, into barite. Based on previous studies on samples dominated by flat terraces with relatively few defects, Sr2+ and Pb2+ adsorb and incorporate at the barite (001)-water interface (Bracco et al., 2019; Bracco et al., 2020). Here, I measured how susceptible lead (Pb) is to desorption and the role surface variability plays in its sorption behavior. First, I measured …


Bullet Ricochet Of Polymer Coated Bullets, Stephen Daly Aug 2021

Bullet Ricochet Of Polymer Coated Bullets, Stephen Daly

Student Theses

Polymer coated bullets were designed to limit a shooter’s exposure to lead. However, despite the advantages that these bullets give there are still difficulties which arise in a forensic firearms examination. Unlike in a typical metal coated bullet, individualizing striations will typically not be imparted to a polymer coated bullet making it unable to be linked to a specific firearm. Due to this difficulty any information that can be gained at the scene of the crime could be crucial. Some obtainable information includes the angle of ricochet and the angle of incidence of the discharged bullet as well as traces …


Weather And Crime: New York State, Yuna Kim Jun 2021

Weather And Crime: New York State, Yuna Kim

Student Theses

The present study assesses the degree to which temperature affects the crime rates in all 62 counties in the State of New York. Five different crimes (i.e., robbery, aggravated assault, burglary; larceny, and motor vehicle theft) for the year 2019 were selected from the Division of Criminal Justice Services of New York to be examined. The current study examined whether the rate of these crimes was associated with the changes in weather, with the assumption that higher weathers would lead to higher property and violent crimes, when controlling for the effect of various control variables. The findings suggest that the …


Top–Down Control On Eruptive Style At Masaya Volcano Inferred From Melt Composition, Lisa Hlinka Sep 2020

Top–Down Control On Eruptive Style At Masaya Volcano Inferred From Melt Composition, Lisa Hlinka

Student Theses

Highly explosive, Plinian-type eruptions of basaltic magma are enigmatic because basaltic melts have lower viscosities than more silicic melts which have traditionally been considered essential for such explosive eruption style. Masaya volcano, Nicaragua, is one of the few basaltic volcanoes to have generated a wide range of eruptive styles, from effusive lava lake activity to voluminous Plinian fall deposits. This volcano thus offers a unique case study to better constrain ideas on basaltic eruption style controls.

We analyze olivine-, plagioclase- and clinopyroxene-hosted melt inclusions as well as matrix glasses from lava lake (LL) ejecta and two Plinian tephra deposits—the 2.1 …


The Relationship Between Impact Energy And Glass Fracture Via .177 Caliber Steel Bbs, Jocenel Beach Aug 2020

The Relationship Between Impact Energy And Glass Fracture Via .177 Caliber Steel Bbs, Jocenel Beach

Student Theses

Fractured glass is often found at shooting scenes and can provide useful information for crime scene reconstruction. Mechanical glass fracture from a projectile impact can result in different types of fracture patterns. The degree of fracture depends on several factors including: type of glass, the thickness of the glass, curvature (if any), distance from the muzzle, contact angle, and type of projectile. Correlating impact energy to the degree of glass fracture can provide useful information regarding the muzzle-to-target distance for a particular firearm/ammunition combination. This research focuses on the projectile impact velocity of .177 steel BBs shot from a pneumatic …


Method Development For Identifying Counterfeit Cigarettes Using Environmental Pollen Analysis, Tiffany Chan Aug 2020

Method Development For Identifying Counterfeit Cigarettes Using Environmental Pollen Analysis, Tiffany Chan

Student Theses

Cigarette counterfeiting negatively impacts government revenue and undermines tobacco control policies. Tracking geographical origins and potential trade routes of counterfeit cigarettes is important for investigation illegal trade in tobacco products. Traditional pollen extraction techniques provide clear residues of pollen trapped on tobacco leaves and used for geographical identification; however, such methods are time-consuming and utilize concentrated chemicals. This study developed a simple, fast and environmentally friendly method for extraction of pollen grains used in differentiating genuine and counterfeit cigarettes. Experimental factors that may affect pollen recovery including number of cigarettes, extraction solution, and extraction temperature, were optimized. The optimum parameters …


Identification And Quantification Of Classic, Prescription, And Synthetic Opioids In Hair By Liquid Chromatography Tandem Mass Spectrometry (Lc/Ms/Ms), Natalia A. Platosz May 2020

Identification And Quantification Of Classic, Prescription, And Synthetic Opioids In Hair By Liquid Chromatography Tandem Mass Spectrometry (Lc/Ms/Ms), Natalia A. Platosz

Student Theses

The current use and misuse of synthetic and prescription opioids in the US has reached epidemic status. According to the US Department of Health and Human Services, every day more than 130 people in the US die after overdosing on opioids, and 2.1 million had an opioid use disorder in 2016. Hair is becoming an alternative matrix of increasing interest in forensic toxicology to investigate drug use and abuse patterns due to its long window of detection. The focus of this project was to develop and validate a method that simultaneously detects and quantifies 27 classic, prescription and synthetic opioids …


Dna Recovery From Handwritten Documents Using A Novel Vacuum Technique, Patrick M. Mclaughlin Aug 2019

Dna Recovery From Handwritten Documents Using A Novel Vacuum Technique, Patrick M. Mclaughlin

Student Theses

Investigations of many crimes such as robberies, kidnappings, and terrorism are often associated with the recovery of a paper document which has been written by the perpetrator. Paper can provide a variety of forensic evidence such as DNA, latent fingermarks, and indented writing. The focus of this study was the collection of probative DNA profiles from the text region of a handwritten note through a vacuum suction device without altering or destroying the document. Collection of DNA evidence was carried out in two separate groups. The first group involved 11 volunteers providing a handwritten note sample with unwashed hands. The …


An Exploration Of Protein And Dna Components In Fingerprint Residue, Ashley Borrego Aug 2019

An Exploration Of Protein And Dna Components In Fingerprint Residue, Ashley Borrego

Student Theses

The main focus of this project was to investigate the protein and DNA components in both sebaceous and eccrine fingerprints. This study investigated the relative content of DNA and proteins in eccrine fingerprints to sebaceous fingerprints. All volunteers were instructed to wash and dry their hands prior to depositing parallel thumbprints. Twenty volunteers were instructed to touch their face to produce sebaceous prints, and 5 volunteers were instructed to wear gloves over a heat source to produce sweaty or eccrine prints. Microscopy was used to score the cellular debris of the right fingerprint on a scale of 1-4 based on …


Development Of A Screening Method For Drugs Of Abuse By Direct Analysis Of Dried Urine Spots Coupled To Mass Spectrometry, Melanie Goldstein Aug 2019

Development Of A Screening Method For Drugs Of Abuse By Direct Analysis Of Dried Urine Spots Coupled To Mass Spectrometry, Melanie Goldstein

Student Theses

Fast and easy screening procedures are essential in any forensic toxicology laboratory to differentiate negative samples from presumptive positive cases. Immunoassay techniques, such as enzyme multiplied immunoassay technique (EMIT), are routinely employed as screening procedures. However, these techniques lack specificity (only differentiate group of drugs and not individual compounds) and it is difficult to add new compounds to the panel. Direct analysis of dried urine spots (DUS) by mass spectrometry (MS) offers a novel strategy to overcome these issues. DUS offer an improved storage alternative for biological samples, reducing costs and space requirements. In this work, an original method to …


The Forensic Analysis Of Children's Temporary Tattoos, Erika Bravo Jun 2019

The Forensic Analysis Of Children's Temporary Tattoos, Erika Bravo

Student Theses

While children’s temporary tattoos have been produced since the 20th century, there are few scientific studies that have evaluated their physical and chemical characteristics. Therefore, this thesis is a preliminary study done to evaluate the composition of children’s temporary tattoos and consider the importance of such traces in a forensic content.

Colored regions in children’s temporary tattoos, such as red, pink, yellow and orange, were found to fluoresce with the use of an alternative light source while the use of microscopy led to the identification of different printing patterns between temporary tattoos. However, limitations in the ability to determine the …


The Forensic Analysis Of Adult Temporary Tattoos, Paige Cooper Jun 2019

The Forensic Analysis Of Adult Temporary Tattoos, Paige Cooper

Student Theses

Adult temporary tattoos have become more popular, yet there is very little research on them, especially regarding their use in forensics. This poses a problem because forensic investigators may not be able to distinguish a temporary tattoo from a real tattoo, possibly hindering their investigation. In this study, various types of adult temporary tattoos were examined and analyzed in attempts to identify and distinguish them, both from each other and from permanent tattoos. Infrared spectroscopy, specifically attenuated total reflection (ATR), proved to be more useful than ultra-violet visible light spectroscopy in terms of analyzing the samples. The natural adult temporary …


Determination Of Anxiolytic And Antidepressant Medicines In New York City Wastewater Samples, Jasmine J. Gayle May 2019

Determination Of Anxiolytic And Antidepressant Medicines In New York City Wastewater Samples, Jasmine J. Gayle

Student Theses

Wastewater-based epidemiology (WBE) provides information about a population’s exposure to certain chemical agents, such as drugs of abuse and medicines, by the analysis of human biomarkers, also known as excretion products, in wastewater samples. Although this is a growing field worldwide, mainly in Europe, Oceania, and Asia, limited data from the US are currently available. We developed and validated an analytical method to quantitatively and qualitatively determine the presence of commonly prescribed drugs to treat anxiety (alprazolam, buspirone, clonazepam, lorazepam, and propranolol) and depression (bupropion, citalopram, clomipramine, duloxetine, fluoxetine, imipramine, paroxetine, sertraline, and venlafaxine) in wastewater using liquid chromatography tandem …


The Forensic Analysis Of Skin-Safe Stamp Pad Inks, Swetha Rajagopal May 2019

The Forensic Analysis Of Skin-Safe Stamp Pad Inks, Swetha Rajagopal

Student Theses

Skin-safe stamp pad inks are currently being used at locations such as clubs, zoos and other events with the purpose of stamping individuals that visit the location. This is done in an attempt to monitor the number and activity of visitors. Ink manufacturing companies generally tend to experiment with a number of different combinations of the different components of ink, in order to obtain desirable properties. The combinations are usually proprietary and that very nature of the inks ends up making them, possibly unique and individual. The analysis, identification and possible individualization of the chemical composition of these inks could …


Revolution In Crime: How Cryptocurrencies Have Changed The Criminal Landscape, Igor Groysman Dec 2018

Revolution In Crime: How Cryptocurrencies Have Changed The Criminal Landscape, Igor Groysman

Student Theses

This thesis will examine the ways in which various cryptocurrencies have impacted certain traditional crimes. While crime is always evolving with technology, cryptocurrencies are a game changer in that they provide anonymous and decentralized payment systems which, while they can be tracked in a reactive sense via the blockchain, are seen by criminals as having better uses for them than traditional fiat currencies, such as the ability to send money relatively fast to another party without going through an intermediary, or the ability to obscure the origin of the money for money laundering purposes. Every week there are new cryptocurrencies …


Building Test Anonymity Networks In A Cybersecurity Lab Environment, John Schriner Aug 2018

Building Test Anonymity Networks In A Cybersecurity Lab Environment, John Schriner

Student Theses

This paper explores current methods for creating test anonymity networks in a laboratory environment for the purpose of improving these networks while protecting user privacy. We first consider how each of these networks is research-driven and interested in helping researchers to conduct their research ethically. We then look to the software currently available for researchers to set up in their labs. Lastly we explore ways in which digital forensics and cybersecurity students could get involved with these projects and look at several class exercises that help students to understand particular attacks on these networks and ways they can help to …


An Improved Method For The Analysis Of Fiber Evidence Using Polarized Light Microscopy, Samuel F. Kaplan Jun 2018

An Improved Method For The Analysis Of Fiber Evidence Using Polarized Light Microscopy, Samuel F. Kaplan

Student Theses

Using the basic fundamentals of polarized light microscopy, a new and improved method for identifying synthetic fibers is presented in this thesis. Using the equation of an ellipse in spherical coordinates, an EXCEL™ (Microsoft Inc., Seattle, WA) spreadsheet was developed that generated tables of data that provide a foundation for a new and more efficient method in fiber analysis. Intermediate refractive index values for each subclass of textile fibers were calculated based on the fiber's principal refractive index values. The angles of refractive index matching to known refractive index fluids vary from 0 to 90 degrees upon rotation of the …


A 3d Characteristics Database Of Land Engraved Areas With Known Subclass, Entni Lin Jun 2018

A 3d Characteristics Database Of Land Engraved Areas With Known Subclass, Entni Lin

Student Theses

Subclass characteristics on bullets may mislead firearm examiners when they rely on traditional 2D images. In order to provide indelible examples for training and help avoid identification errors, 3D topography surface maps and statistical methods of pattern recognition are applied to toolmarks on bullets containing known subclass characteristics. This research was conducted by collecting 3D topography surface map data from land engraved areas of bullets fired through known barrels. This data was processed and used to train the statistical algorithms to predict their origin. The results from the algorithm are compared with the “right answers” (i.e. correct IDs) of the …


Ethics And Bias In Machine Learning: A Technical Study Of What Makes Us “Good”, Ashley Nicole Shadowen Dec 2017

Ethics And Bias In Machine Learning: A Technical Study Of What Makes Us “Good”, Ashley Nicole Shadowen

Student Theses

The topic of machine ethics is growing in recognition and energy, but bias in machine learning algorithms outpaces it to date. Bias is a complicated term with good and bad connotations in the field of algorithmic prediction making. Especially in circumstances with legal and ethical consequences, we must study the results of these machines to ensure fairness. This paper attempts to address ethics at the algorithmic level of autonomous machines. There is no one solution to solving machine bias, it depends on the context of the given system and the most reasonable way to avoid biased decisions while maintaining the …


Study Of Self-Similarity In Brain Data, Jennifer Holst Dec 2017

Study Of Self-Similarity In Brain Data, Jennifer Holst

Student Theses

In the area of computer science, past research has found that the concept of self-similarity is present in local and Internet-based network traffic. This study considers the possibility that data traveling through the neuronal network in the human brain is also self-similar. By analyzing publicly available raw EEG data and estimating its Hurst parameter, we find indications that brain data traffic may in fact be self-similar.


Digital Anti-Forensics: An Implementation And Examination, Stephanie Dachs Aug 2017

Digital Anti-Forensics: An Implementation And Examination, Stephanie Dachs

Student Theses

The rise of computer use and technical adeptness by the general public in the last two decades are undeniable. With greater use comes a greater possibility for misuse, evidenced by today’s incredible number of crimes involving computers as well as the growth in severity from that of cyber hooliganism to cyber warfare. Although frequently utilized for privacy and security purposes, the vast range of anti-forensic techniques has contributed to the ability for hackers and criminals to obstruct computer forensic investigations.

Understanding how anti-forensics may alter important and relevant data on an electronic device will prove useful for the success and …


The Quantification Of Cocaine From The Erythroxylum Coca Plant And The Comparison On High Performance Liquid Chromatography And Gas Chromatography Mass Spectroscopy As An Analytical Method., Tuesday James Jun 2017

The Quantification Of Cocaine From The Erythroxylum Coca Plant And The Comparison On High Performance Liquid Chromatography And Gas Chromatography Mass Spectroscopy As An Analytical Method., Tuesday James

Student Theses

Cocaine is derived from the Erythroxylum coca plant, is a highly addictive stimulant abused all over the world. There are two types of Erythroxylum coca plants that produce cocaine; the E. Coca and E. Novogranatense. Cocaine exists as the salt, and the freebase which is typically referred to as “crack” due to the crackling sound it makes when heated. It is popular because it is inexpensive and easily available on the streets, mainly in poor urban areas. The purpose of this project was to determine the amount of cocaine that can be extracted from E.coca and to assess which analytical …


Detection Of Cathinone And Mephedrone In Plasma By Lc-Ms/Ms Using Standard Addition Quantification Technique, Theron W. Ng-A-Qui May 2017

Detection Of Cathinone And Mephedrone In Plasma By Lc-Ms/Ms Using Standard Addition Quantification Technique, Theron W. Ng-A-Qui

Student Theses

Designer drugs are structural analogs of Drug Enforcement Agency (DEA) Schedule I and II substances. They are synthesized to mimic the effects of illegal drugs of abuse and to bypass the provisions of drug regulations. Despite the increased availability of designer drugs, few studies have focused on specific analytical extraction techniques for their detection and quantification in biological samples. Solid phase extraction (SPE) is the most commonly used technique for sample preparation. The purpose of this study is to evaluate the extraction efficiency of the various SPE columns with different sorbent materials for two designer drugs, cathinone and mephedrone in …