Forensic Science and Technology Commons^™

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

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 …

The Y-Screen Assay: Validation And Evaluation Of Subsequent Str Success, Kassandra Luyando

Student Theses

There are hundreds of untested sexual assault kits in police custody. As of 2017, New York State passed a law stating that all untested kits must be turned over to forensic laboratories to be tested, causing backlogs at laboratories to increase. The Y-Screen assay is a DNA extraction protocol which utilizes NaOH to rapidly lyse epithelial and sperm cells, and the Quantifiler Trio DNA quantification kit to detect the presence or absence of male DNA prior to standard sample processing. The Y-Screen assay is a commercial product used in this research to test a defined set of validation samples with …

Evaluation Of Illumina’S Forenseqtm Signature Prep Kit For Eye And Hair Color As Well As Biogeographical Ancestry Predictions, Krupa Vijaykumar Jani

Student Theses

This study examined and analyzed 266 samples using ForenSeq^TM Signature Prep Kit B. Samples from various populations such as African American, East Asian, South Asian, European, and Mixed population were included in the study. Primer Mix B targets 27 autosomal STRs (aSTRs), 24 Y-STRs, 7 X-STRs, and 94 identity Single Nucleotide Polymorphisms (iSNPs), 24 phenotypic SNPs (pSNPs), and 56 ancestry SNPs (aSNPs), coming to a total of 231 targets. The study mainly focused on the quality of data generated by the instrument as well as for the accuracy of eye and hair color as well as biogeographical ancestry predictions …

Ant Predation Of Blow Flies During Decomposition And Its Potential Impact On Pmi Estimations, Vincent J. Nappi

Student Theses

When an organism dies, the process of decomposition begins and many insects are attracted to the decomposing remains, or carrion, as a prospective food source for themselves, or their offspring. Blow flies (Family: Calliphoridae), in particular, are one of the first insects to discover and colonize a dead body due to the ability to detect a decomposing resource from large distances. As a result, forensic entomologists take advantage of the behavior and developmental cycles of early colonizers to calculate the post-mortem interval (PMI) in order to determine the time since death. However, along with the insects that are attracted to …

Range Of Detection For Proteins And Dna From Fingerprints On Fired And Unfired Cartridge Casings, Stacey-Ann R. Sterling

Student Theses

Cartridges and spent cartridge casings can be probative pieces of evidence. Unfortunately due to a combination of factors such as exposure to high temperatures and initially low amounts of biological material on the surface, DNA testing so far has been mostly unsuccessful for these items. Typing other marker systems, such as protein polymorphisms, on the same biological evidence would add power of discrimination. To explore this option we developed a DNA-protein trypsin-based co-extraction method that was optimized for unfired and fired cartridges. Various sample wet and dry collection methods and multiple metal casings, such as aluminum, nickel, steel, and brass …

Optimizing A Method For Simultaneous Recovery Of Proteins And Dna From Fingerprints, Steven Kranes

Student Theses

DNA testing on touched objects is a valuable tool in forensic investigations, but DNA is usually present in low amounts, causing poor STR typing results. For touch DNA evidence, there is a clear need for additional individualization, especially for highly probative samples. This could be achieved by testing genetically variable proteins. The goal of this project was to develop a DNA/protein co-extraction method to facilitate DNA and protein testing on the same evidence item. Existing DNA extraction methods were carefully adjusted to allow for downstream mass spectrometry analysis. Initial experiments on saliva and fingerprints placed on glass suggested that trypsin …

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 …

Species Identification Of Necrophagous Insect Eggs Based On Amino Acid Profile Differences Revealed By Direct Analysis In Real Time-High Resolution Mass Spectrometry, Justine E. Giffen, Jennifer Y. Rosati, Cameron M. Longo, Rabi A. Musah

Publications and Research

The colonization of decomposing remains by necrophagous insects such as blow flies is of forensic importance because the progression through the various stages of insect development can be correlated to time of death. The ability to infer this information hinges on accurate determination of the fly species that are associated with the entomological evidence collected. This evidence can include eggs, larvae, pupae, and puparial casings. Determination of the egg’s identity is particularly challenging because the eggs of multiple species are morphologically very similar. We report here that the species identity of fly eggs can be determined from their chemical fingerprint …

The Advanced Spectroscopic Analysis Of Organic Gunshot Residue And Explosives, Jennifer M. Leonard

Dissertations, Theses, and Capstone Projects

With the prevalence of shooting cases and terrorist attacks/or threats that plague the current state of the criminal justice system, it is of paramount importance to be able to detect, identify and interpret the presence of gunshot residue or explosives material. This concern is seen in law enforcement agencies and the media throughout the United States and abroad.

Currently, the typical method of analyzing gunshot residue in most crime laboratories serves to identify the inorganic constituents of the primer residue, namely lead, barium and antimony. However, it is possible that the organic matter from the propellant could provide different information …

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 …

Bayesian Approach To Toolmark Analysis, Antonio W. Del Valle

Student Theses

Statistical analysis of toolmarks using frequentist methods can be problematic for assorted reasons. Thus, in order to analyze toolmarks whilst avoiding these issues, a Bayesian approach is taken. Specifically for this thesis we discuss the computation of a specific Likelihood Ratio for toolmark comparisons. This Bayesian based approach involves using data already at hand in conjunction with a probability model in order to establish an estimate for its “value”, i.e. the “weight of evidence”. Making the calculations to obtain a Likelihood Ratio is very cumbersome and time consuming. Also many commercial software packages hide the process and underlying assumptions that …

Chemical Identification Of Synthetic Cannabinoids In Herbal Incense Products, Karol F. Alvarez Heredia

Student Theses

The emergence of synthetic cannabinoids is an ongoing challenge for forensic, clinical analytical chemists and toxicologists. Different analogs are continuously introduced in the market to circumvent the legislation and to enhance their pharmacological activity. In the present project, a total of seven synthetic cannabinoids were identified in four herbal incense products by employing GCMS, and LC-TOF. Fractional collection of four out of the seven synthetic cannabinoids was performed using HPLC followed by the collection of FTIR-ATR spectra. Five out of seven synthetic cannabinoids were classified as indazole carboxamide derivatives, which include 5Fluoro-EMB-Pinaca, 5Fluoro-AMB, MA-Chminaca, AB-Chminaca, and 5Fluoro-AKB-48. The remaining two …

Quantitative Analysis Of Opioids And Cannabinoids In Wastewater Samples, Alethea Jacox, Jillian Wetzel, Shu-Yuan Cheng, Marta Concheiro-Guisan

Publications and Research

Wastewater-based epidemiology is an innovative approach that uses the analysis of human excretion products in wastewater to obtain information about exposure to drugs in defined population groups. We developed and validated an analytical method for the simultaneous determination of opioids (morphine, oxycodone, hydrocodone, oxymorphone and hydromorphone), and cannabinoids (Δ⁹-tetrahydrocannabinol, 11-nor-9-carboxy-tetrahydrocannabinol (THCCOOH) and THCCOOH-glucuronide) in raw-influent wastewater samples by ultra-high performance liquid chromatography-tandem mass spectrometry. Method validation included linearity (5–1 000 ng/L for opioids, 10–1 000 ng/L for cannabinoids), imprecision (<21.2%), accuracy (83%–131%), matrix effect (from –35.1% to –14.7%) and extraction efficiency (25%–84%), limit of detection (1–5 ng/L) and quantification (5–10 ng/L) and auto-sampler stability (no loss detected). River and wastewater samples were collected in triplicate from different locations in New York City and stored at −20 °C until analysis. Water from sewage overflow location tested positive for morphine (10.7 ng/L), oxycodone (4.2–23.5 ng/L), oxymorphone (4.8 ng/L) and hydromorphone (4.2 ng/L). Raw influent wastewater samples tested positive for morphine (133.0–258.3 ng/L), oxycodone (31.1–63.6 ng/L), oxymorphone (16.0–56.8 ng/L), hydromorphone (6.8–18.0 ng/L), hydrocodone (4.0–12.8 ng/L) and THCCOOH (168.2–772.0 ng/L). This method is sensitive and specific for opioids and marijuana determination in wastewater samples.

Genetic Markers For Sex Identification In Forensic Dna Analysis, Erin Butler, Richard Li

Publications and Research

The ability to determine the sex of an individual based on DNA evidence can be crucial in instances such as identification of victims of mass disaster, missing persons investigations, and sexual assault cases. The Y chromosome marker amelogenin is currently in widespread use for determination of chromosomal sex of an unknown DNA donor and differentiating the relative contributions of male and female DNA in a mixed forensic sample. However, many cases of the failure of the amelogenin marker to correctly determine the sex of DNA donors have been reported, causing the usefulness of the amelogenin marker in forensics to be …

An Enzymatic Method To Process Decomposed Non-Human Bone For Forensic Dna Analysis, Richard Li, Melissa Gaud, Smriti Nair

Publications and Research

Forensic analysis of DNA from non-human bones can be important in investigating a variety of forensic cases. However, decomposed bone is difficult to process for isolating DNA. In this study, a previously established enzymatic method was utilized to process bone samples that simulate decomposed specimens. Our results demonstrated that this enzymatic processing method is effective for removing decomposed soft tissues and outer surface materials such as mineralized bone connective tissue of bone fragment samples. Our data suggested that this method can be used in the initial sample preparation for cleaning the outer surface of decomposed non-human skeletal fragments. This study …

Forensics Far More Than What’S Seen On Tv, Aldemaro Romero Jr.

Publications and Research

No abstract provided.

Qualitative And Quantitative X-Ray Diffraction Analysis For Forensic Examination Of Duct Tapes, Rebecca E. Bucht

Dissertations, Theses, and Capstone Projects

Duct tapes are an increasingly important class of forensic evidence. This research has studied the value of using x-ray diffraction (XRD) to extend the ability of evidence examiners to gain additional information about a duct tape specimen.

Duct tapes are composed of five different layers. Starting from the non-adhesive side, these layers are the release coating, backing, scrim, primer and adhesive. The release coating assists in reducing unwind tension and preventing the tape from sticking to itself when on a roll. The backing layer serves as a support for the adhesive, and is usually based on polyethylene. The scrim is …