Forensic Science and Technology Commons^™

Coomassie Brilliant Blue Dye As A Method For Analyzing Fracture Markings In Bone, Abigail Hoffmeister, David Harutunyan, Matthew Aizawa, Everett Baker, Brandon Mendoza, Chase Freeman, Siran Iskanian

Seaver College Research And Scholarly Achievement Symposium

Coomassie Brilliant Blue Dye is a dye commonly used to stain proteins. Because of its ability to adhere to proteins, this research has focused on perfecting a method of dyeing a fractured flat bone in order to most accurately observe and analyze fracture markings within the trabecular layer. Stereoscopic microscopy was the chosen technique of analysis for this research because of its proven effectiveness in glass and ceramic fractography to observe varying depths. In order to most effectively apply stereoscopic microscopy to this research, the following variables were manipulated to maximize color contrast in the trabecular layer in order to …

Extraction Of Challenging Forensic Samples Using The Microgem Dna Extraction Kit, Falyn R. Vega

Student Theses

In forensic science, DNA extraction can be a tedious and resource-intensive process. Extraction with Proteinase K is an industry standard but has its drawbacks, such as requiring multiple ionic detergents and washing steps. MicroGEM has developed a new enzyme called forensicGEM that is temperature-dependent and compatible with mesophilic enzymes, offering complete DNA extraction in about 20 minutes in a single tube, limiting contamination, loss of sample, and working time. ForensicGEM can extract DNA from highly degraded samples, potentially leading to more complete STR profiles. Highly degraded tissue and bone samples were collected and extracted with the forensicGEM …

Structural Integrity And Stability Of Dna In Ionic Liquid And Near-Infrared Indolizine Squaraine Dye, Ember Yeji Suh

Honors Theses

Luminol, the most common presumptive test for blood at a crime scene, has multiple issues, such as false positive results with chemical agents, no luminescence due to “active oxygen” cleaning agents on bloodstains, and inability to penetrate textile materials. A combination of indolizine squaraine dye and ionic liquid (IL), or Dye Enhanced Textile Emission for Crime Tracking (DETECT), have shown potential to address these issues. The purpose of this study was to assess the binding mechanism of CG (1:1) and SO₃SQ dye to HSA and how the mechanism can explain the W214 fluorescence quenching effect and to determine …

Bci Validation: Yfiler Plus Kit Validation, Chloe Koon

Honors Projects

In order to have access and use the Combined DNA Index System (CODIS), it is required by the Federal Bureau of Investigation's Quality Assurance Standards (FBI-QAS) for Forensic DNA Units to complete comprehensive validation studies on all equipment, materials, and methods used in the process of DNA analysis. This study continues validation previous done within the Ohio Bureau of Criminal Investigation (BCI). YFiler Plus is a DNA amplification kit that is used in cases where it is most useful to examine only male DNA profile(s) within a sample by amplifying loci only on the Y-Chromosome. Components of this study include …

Scientific Development Of An Integrated Workflow For Latent Print, Questioned Document, And Dna Processing Of Paper Evidence, Ashley Morgan

Dissertations, Theses, and Capstone Projects

Touch paper evidence could be the source of probative human DNA but recovery is challenging and forensic laboratories instead prioritize processing by the Latent Print and Questioned Document disciplines. Recent advances in DNA collection methods and the increased sensitivity of STR typing kits have improved success rates for DNA testing of paper evidence; but prior to implementing DNA collection, laboratories have to decide in which order to examine paper for the different types of forensic evidence. This thesis developed and tested a multi-discipline workflow for processing paper evidence by DNA, Latent Prints and Questioned Documents experts. Preliminary sampling studies indicated …

Complex Dna Mixture Deconvolution By Single Cell Genomics: Direct Physical Cell Subsampling And High Sensitivity Dna Typing, Kaitlin Huffman

Electronic Theses and Dissertations, 2020-

Biological evidence is often found at crime scenes and can comprise of DNA from the victim(s) and perpetrator(s) to a crime as well as from individuals with no direct relationship to the incident. This can complicate analysis as DNA mixtures are one of the more difficult sources of biological evidence to interpret. Probabilistic genotyping (PG) has greatly aided in mixture analysis. However, even with PG, standard bulk mixture approaches do not always result in probative results as allele overlap, artifacts, or low-level minor contributors inevitably cause genotype information loss. Therefore, deconvolution of forensic DNA mixtures into their individual component DNA …

Reproducibility Of Individual Dna Deposits Detected Through Cellular Fluorescence, Natalee Small-Davidson

Student Theses

Contact traces are an important part of DNA casework, but the probative value of any identified associations depends on the possibility of passive transfer. There is known individual variation in DNA left behind during contact, this DNA shedding propensity has an effect on whose DNA is detected. This study evaluated this variability using a cell staining approach. Volunteers were asked to deposit a fingerprint on a clean glass slide, then wash their hands and deposit a second fingerprint after a 30-minute wait without touching anything. Three sets of samples were collected over three consecutive weeks. Fingerprints were stained with a …

Evaluation Of The Trunarc Handheld Narcotics Analyzer As A Pre-Analysis Screening Device For The Orange County Crime Lab, Sarah Yang, D. Bauer, C. Woltz, S. Soto, Michael Ibba

Student Scholar Symposium Abstracts and Posters

Forensic analysis of suspected narcotics is often dangerous as the substances’ composition is unknown. Many techniques for drug identification require handling of the substance outside of its packaging, which can expose the analyst to potentially harmful chemicals. The TruNarc Handheld Narcotics Analyzer is a portable Raman spectroscopy device that is non-destructive of evidence and can be used to screen drugs through simple packaging to minimize the risk of exposure. The Orange County Crime Lab (OCCL) is testing the limits of this device to determine if it can be used to screen new evidence within the Seized Drugs Lab. The OCCL …

Determination Of Human Shedding Propensity Based On Str Results, Genevieve Trapani

Student Theses

Trace DNA evidence may be discovered at a crime scene after having been deposited by a person of interest via active or passive transfer. Based on previous studies, passive transfer of one’s DNA is influenced by their shedding propensity, or probability of depositing a detectable amount of DNA through touch. Determining the shedding propensity of a person of interest can aid in trace DNA interpretation in forensic casework. This study explored STR profile quality and the presence of a DNA mixture for different skin surface locations, including fingertips before and after handwashing. As expected, unwashed fingers showed a higher prevalence …

Performance Of A Dna And Protein Co-Extraction With Trypsin In Comparison To Two Proteinase K Based Dna Extraction Methods, Dinura A. Gunatilake

Student Theses

Effective DNA extraction methods are important for forensic applications. The main goal of this experiment was to determine if a newly developed trypsin based protein/DNA co-extraction method applied to contact traces would yield comparable results to a commercial Proteinase K method (QIAamp DNA Investigator Kit) and a Chelex extraction method with Tween 20 used in forensic laboratories. This was tested on 20 sets of sebaceous fingerprints on glass slides.

The results of this study demonstrate the trypsin co-extraction method yielded the highest amount of DNA. In the first comparison, the mean total DNA yields for the trypsin-co extraction method and …

Discrimination Of Monozygotic Twins Using Dna Methylation Levels Of One Cpg Site At Chromosome 3, Dino O. Robinson

Student Theses

Conventional STR typing, commonly used in forensics for human identification, poses a problem in criminal cases and paternity disputes involving monozygotic (MZ) twins because they share identical DNA sequences. To date, no routine method is available in forensics to differentiate between individuals of MZ pairs. Recently, epigenetic methods measuring differential DNA methylation patterns have been applied to MZ twin differentiation. In this study, we investigated the potential to identify MZ twins using a previously identified DNA methylation site in chromosome 3, cg18562578, in a sample of 129 MZ and 37 dizygotic (DZ) twin pairs. We used bisulfite converted saliva DNA …

Development Of A Quantitative Pcr (Qpcr) Based Method For Studying Temporal Dna Degradation In Waterlogged Bone, Isis Thornton

Master of Science in Forensic Science Directed Research Projects

Human activities are often centered around the presence of water, thus it is not surprising that there are many water-related human deaths. Accumulated degree days (ADD), and other aquatic variables may affect DNA retrieval from waterlogged bone. Calcium and collagen in bone can inhibit the PCR necessary to produce an STR profile; the current solution is a time-consuming organic extraction. While there are examples of research on DNA degradation in terrestrial bone over time, there has been little work done on submerged bone samples and they are usually limited to case studies. The major aim of this study was to …

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 …

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 Collection Of Trace Biological Samples From Vehicle Headrests, Kevin Tang, Jesse Ramirez, John Bond, Jocelyn Weart, Yvette Delatorre, Ian Fitch, Steven Lee

Themis: Research Journal of Justice Studies and Forensic Science

Tape-lifting and swabbing are two methods commonly used for collecting biological samples in the United Kingdom and United States to investigate vehicle crimes. Determining the optimal collection method may lead to an increase in generating DNA profiles and crime-solving. The objective of this study is to evaluate the efficiency of adhesive tape and the double-swab collection methods for investigating vehicle crimes with possible touch DNA samples. Two experiments were conducted to evaluate the use of tape-lifts and swabs on spiked common vehicle fabric materials. The efficiency of recovery between the two collection methods was performed using qPCR. The results from …

Tracking The Sexual Assault Kit Backlog, Kallie Crawford, Lyndsie Ferrara

Undergraduate Research and Scholarship Symposium

The backlog of untested sexual assault kits is a national problem. Numerous federal funding opportunities offer the forensic science and law enforcement communities valuable resources needed to test the kits, but issues still remain. The majority of resources are focused on the collection and testing of sexual assault kits, but the tracking of the kits has not been a primary focus. This research highlights improvements that can be made to better understand the current backlog and improve the future processing and tracking of kits. Given the lack of a universal evidence tracking database among agencies, tracking sexual assault kits seems …

Fors 401: Forensic Biochemistry—A Peer Review Of Teaching Project Inquiry Portfolio, Ashley Hall

UNL Faculty Course Portfolios

Students who participate in active and experiential learning activities develop a better understanding of basic scientific principles and are also more likely to be retained in a STEM discipline. Developing such activities, however, can be difficult. In the present study, we sought to develop classroom activities to engage university students and increase understanding of the theory and practice of forensic science. One common accessory amongst the target audience was the ever-present media, both social and popular (entertainment). In fact, a majority of students report watching at least one of the many popular forensic science shows on TV. Therefore, we hypothesized …