Legal Studies Commons^™

Evaluation Of Direct-To-Amplification Cell Lysis Techniques For Forensically Relevant Non-Sperm Cells, Rhea Arya

Master of Science in Forensic Science Directed Research Projects

While efforts have been made to reduce the pervasive backlog of sexual assault evidence collection kits, the actual laboratory process remains very time-consuming due to the requirement of a differential lysis step before DNA purification, as well as intricate mixture analysis towards the end of the DNA workflow. Previous work in the Dawson Green laboratory at VCU has developed alternative solutions for differential extractions with sexual assault samples using both an in-tube and microdevice assay. Prior work led to the identification of an alternative sperm lysis method – alkaline lysis using 1M NaOH. However, the current lysis method used for …

Optimization Of Microfluidic Device Methodology For Optical Trapping Epithelial Cells In A Mixture, Brittney N. Hackworth

Master of Science in Forensic Science Directed Research Projects

Evidence containing biological mixtures can make DNA interpretation more difficult due to ambiguous allele calls and artifacts that may be present within electropherograms. Separating out these cell mixtures can be advantageous to the analysts’ analysis methods for identifying STR profiles with higher accuracy. A potential cell separation method that could be implemented in the beginning of the forensic DNA workflow is optical trapping.

This research utilized a 5W ytterbium linearly polarized laser split into two optical traps, paired with a microfluidic device to isolate spermatozoa and vaginal epithelial cells from a 1:1 mixture of vaginal fluid and 1:20 diluted seminal …

Horizontal And Vertical Transmission Of Microbes Associated With Blow Flies Of Forensic Importance, Gabrielle Alisa Burton

Master of Science in Forensic Science Directed Research Projects

Entomological and microbiological evidence can be used in the estimation of postmortem intervals (PMI). This study observes the horizontal and vertical transmission of the microbial community associated with blow flies of forensic importance. Variable region four (V4) of the 16S ribosomal DNA (16S rDNA) was amplified and sequenced from various life stages of blow flies (n=72) using dual-index high throughput sequencing strategy on the MiSeq FGx platform. No significant difference in bacterial community structure was observed between blowfly adults with carrion access and blowfly adults with no carrion access. Dysgonomonas, unclassified Proteobacteria, Escherichia, Ignatzschia, Providencia, …

Comparison Of Cell Counts To Dna Yield In Mock Biological Evidence Samples, Jacob Sewell

Master of Science in Forensic Science Directed Research Projects

The implementation of rapid DNA analysis systems is of interest to forensic DNA casework, as this technology exhibits a sample-to-profile time of approximately two hours with limited handling of samples. This decreases the likelihood of contamination, and can potentially reduce DNA backlogs; however, current rapid DNA analysis systems do not execute one crucial step of the forensic DNA analysis workflow: human DNA quantitation. This step is necessary for DNA profiles to be compliant with the FBI’s Quality Assurance Standard 9.4, allowing DNA profiles to be uploaded and searched within the CODIS database. Coupling traditional qPCR methods with rapid DNA analysis …

Development And Validation Of Microrna Markers For Forensic Body Fluid Identification Using Rt-Qpcr, Jane Goble

Master of Science in Forensic Science Directed Research Projects

Body fluid identification is one of the first and most fundamental steps in the forensic DNA workflow. It allows analysts to determine where a sample might exist on an item of evidence, as well as the type of sample that they are dealing with. However, current serological methods have been documented to produce false or inaccurate results in some cases, and may consume large amounts of sample during processing. Molecular methods, such as the use of microRNA and microbial profiles have been introduced as a means to increase specificity of testing, and have even been combined into a singular assay …

Dna Transfer And Persistence On Non-Porous Surfaces Submerged In Spring Water [Preliminary Study], Morgan L.. Korzik, Josep De Alcaraz-Fossoul, Michael S. Adamowicz, David San Pietro

Forensic Science: Faculty and Staff Publications

Submerged items are often thought to lack evidentiary value. However, previous studies have shown the ability to recover DNA from submerged porous items for upwards of six weeks. The crevices or interweaving fibers in porous items are thought to protect DNA from being washed away. It is hypothesized that, because non-porous surfaces do not have the same traits that might aid in DNA retention, then DNA quantities and the number of donor alleles recovered would decrease over longer submersion periods. Additionally, it is hypothesized that DNA quantity and the number of alleles would be negatively affected by flow conditions. Neat …

Assessment Of The Acidified Hydrogen Peroxide Method On Uncontrolled Fired Cartridge Case Samples, Kylie S. Richardson

Master of Science in Forensic Science Directed Research Projects

The use of fingerprints to identify individuals in forensic cases has been useful for many years due to the persistence and individuality of the prints. In addition, the presence of firearms in forensic casework is steadily increasing over the years. This study aims to expand upon prior research in the development and recovery of latent prints on fired, brass ammunition using an acidified hydrogen peroxide method. Although latent prints are left on the cartridge casing of ammunition during the handling and loading of ammunition into the firearm, it is hypothesized that the pressure within the barrel of the firearm during …

Development Of A Loop-Mediated Isothermal Amplification (Lamp) Assay For Detection Of Mirnas, Alisha B. Whelan

Master of Science in Forensic Science Directed Research Projects

Body fluid identification serves a vital role in contextualizing biological evidence received in forensic laboratories. While several fluids can be presumptively detected using immunological or catalytic tests, these tests are susceptible to false results and have limited sensitivity. True confirmatory testing is still somewhat limited in forensic laboratories. With the advancement of DNA typing technologies, laboratories can develop DNA profiles from trace amounts of sample, increasing the demand for sensitive and accurate body fluid detection. This project proposes using loop-mediated isothermal amplification (LAMP) as a method to rapidly detect microRNAs (miRNAs) that are differentially expressed in various body fluids with …

Stability And Variation Within Donors Of Mirna Markers For Body Fluid Identification, Kelsey R. Price

Master of Science in Forensic Science Directed Research Projects

Traditional enzymatic tests for body fluid identification are prone to false negatives, false positives, and several body fluids do not have confirmatory or reliable presumptive tests. Therefore, molecular-based tests may be more reliable, such as messenger RNA (mRNA), microbial DNA, or microRNA (miRNA) assays.

miRNAs are small, noncoding RNAs whose main function in-vivo is the regulation of protein expression by selectively suppressing the translation of their corresponding mRNAs. They also lack a poly-A tail, and because of this, their small size, and their association with other molecules such as the RISC protein complex, they are more robust than other RNAs, …

A Quantifiler Trio-Based Hrm Mixture Screening Assay For The Quantstudio 6 Flex Qpcr Platform, Dayanara A. Torres

Master of Science in Forensic Science Directed Research Projects

At present, the forensic DNA workflow is not capable of providing information about the contributor status (single source vs. mixtures) of evidentiary samples prior to end-point analysis. This shortcoming can exacerbate the challenges inherent to mixtures and low-template DNA samples. Provided additional sample information earlier in the workflow, protocols could be implemented to mitigate these challenges. High-resolution melt (HRM) curve analysis is a technique used to detect genetic variation in DNA fragments and in the last decade has been evaluated for use in differentiation of samples by genotype and/or contributor status. To this end, a proof-of-concept HRM assay using the …

Optimization And Comparison Of Methods For Separation Of Spermatozoa From Superabsorbent Polymer-Containing Forensic Evidence, Hannah Wells

Master of Science in Forensic Science Directed Research Projects

Sexual assault is currently one of the most prevalent crimes that affects victims of all ages. Forensic DNA analysts often confirm proof of contact in sexual assault cases through the identification of spermatozoa and subsequent STR profiling. Diapers and other feminine hygiene products, such as maxi pads and ultrathin pads, are types of superabsorbent polymer-containing evidence that complicate the process of DNA analysis due to the trapping of the spermatozoa in the gel-like matrix. In this study, a comparison of methods was performed to determine which extraction technique produces the highest sperm cell and DNA yield and generates a usable …

Impact Of 1,4-Dithiothreitol (Dtt) On Microbial Community Structures Associated With Human Semen Samples, Christian R. Blaise

Master of Science in Forensic Science Directed Research Projects

Body fluid identification (BFID) is one of the most important steps in forensic science as it provides important context to how DNA analysis should be performed on biological samples found at the scene of a crime. Many scientific methods on BFID have been developed over the years with respective benefits and flaws. One emerging method in recent years is microbial signature based BFID. This method uses the same DNA extract that is utilized for human DNA profile generation for microbial analysis. Although DNA is extracted from all body fluid samples without any additional steps, extraction of human DNA from semen …

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 …

Powerplex® Fusion 6c System Versus Powerplex® Fusion 5c: A Comparison Of Performance Metrics, Caitlin M. Mccaughan

Master of Science in Forensic Science Directed Research Projects

Following the FBI mandated expansion of the CODIS core loci from 13 to 20, several manufacturers developed short tandem repeat (STR) typing kits in response to the new criteria. One such manufacturer was the Promega Corporation, which released the PowerPlex® Fusion 5C megaplex STR typing kit (Fusion 5C) in 2012. Currently, the Virginia Department of Forensic Science (VDFS) utilizes this amplification kit for both casework and database applications. In 2015, Promega released the PowerPlex® Fusion 6C STR typing kit (Fusion 6C), which contains three additional loci beyond those included in PowerPlex® Fusion 5C, and a sixth color channel. The power …

Creation And Optimization Of An Optical Trapping Microfluidic Device For The Separation Of Mock Forensic Sexual Assault Samples, Mackenzie Lally

Master of Science in Forensic Science Directed Research Projects

Cell mixtures are often seen in forensic samples and commonly involve sexual assault cases where mixtures of sperm cells and vaginal epithelial cells are frequently encountered. This produces challenges in downstream analysis in the form of STR mixture profiles. The only method currently in use in crime laboratories for front-end sperm and epithelial cell separation is differential extraction. This method often results in STR mixture profiles due to carryover into both the male and female fractions and suffers from a wide range of efficiency depending on the laboratory or individual processing the sample. Optical trapping offers an alternative method for …

Evaluation Of Cell Lysis Techniques For Direct Amplification Of Sexual Assault Samples, Sarah Schellhammer

Master of Science in Forensic Science Directed Research Projects

Sexual assault is one of the most common crimes committed today with a delay in sample processing, resulting in the “rape kit backlog”. The traditional method to extract DNA from these samples containing both male and female DNA is a differential extraction; taking hours to process. This study examined a variety of different cell lysis techniques to develop a method which can consistently generate high-quality profiles at a fast rate and with low volumes when compared to the currently used method in our laboratory.

Six lysis methods, in addition to the currently used forensicGEM™ Sperm kit, were performed on …

Evaluation Of Dna Extraction Efficiencies Of Promega’S Dna Iq™ Methods And Casework Extraction Kit For Low Template Samples, Emily M. Anderson

Master of Science in Forensic Science Directed Research Projects

Biological evidence from crime scene samples frequently contain low levels of DNA, such as the most predominant form of evidence, which is DNA deposited by handling objects or “touch evidence”. To maximize the DNA yield recovered from theses challenging samples, forensic laboratories must optimize the extraction methods utilized to isolate and purify DNA for downstream short tandem repeat (STR) amplifications. Currently, the Virginia Department of Forensic Science (VADFS) uses a DNA IQ™ System (DNA IQ) extraction method for isolation of DNA from most forensic samples. This extraction procedure, which combines DNA IQ™ lysis buffer and Dithiothreitol (DTT), has been validated …

Postmortem Interval Estimation Based On Eukaryotic Community Associated With Soil Under Decomposing Porcine Remains, Amanda M. Haase

Master of Science in Forensic Science Directed Research Projects

Recent studies have shown that bacteria associated with soils under a carcass change significantly both temporally and spatially. These studies were done in both laboratory and field conditions, but with limited replications. In addition, limited information exists on temporal and spatial changes in eukaryotic community structure associated with soil under decomposing remains. This study was designed to fill in these gaps and expand on previous studies to improve postmortem interval (PMI) estimation techniques as well as to identify cadaver decomposition islands (CDI) based on eukaryotic community structure associated with soil under vertebrate remains. To accomplish this goal, soil samples were …

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 …

Expanded Testing Of An Integrated Qpcr Mixture Screening Assay Using High Resolution Melt Curve Analysis And Support Vector Machine Modeling, Andrea L. Williams

Master of Science in Forensic Science Directed Research Projects

In the conventional forensic DNA workflow, the number of contributors in a sample is unknown until the final step of STR analysis. We propose a high-resolution melt curve (HRM) mixture screening assay, which uses support vector machine (SVM) modeling of melt morphologies of D5S818 and D18S51 amplicons integrated into a common qPCR-based human DNA quantification kit, to differentiate between single-source samples (and their genotypes) and mixtures at an earlier stage in the DNA workflow (quantification). Previously, using data generated from whole melt curves, 87.5% of single-source samples and 100% of 1:1 mixture samples (2 contributors) classified accurately.

In this study, …

Analysis Of Error Within Forensic Measurements And Photogrammetry Programs, Amy Douglas

Honors Theses

Digital images and photography have been considered commonplace in forensic science since the late 1990’s. Photogrammetry is a tool used in forensic science to measure objects within photographs that contain a scale or programs that are able to measure items in 3D images. Items at crime scenes often need to be measured and forensic scientists may not know what the best option is for their situation. This research will be conducted to show which type of measurement technique is most accurate, calculated against NIST traceable measurements, at various sizes of objects. The measurement techniques that will be tested are standard, …

Determination Of Vehicle Speed From Recorded Video Using Reverse Projection Photogrammetry And File Metadata, Brandon Epstein, Bryce Westlake

Faculty Publications

The prevalence of security and in‐car video has increased the number of motor vehicle accidents captured on digital video. However, inconsistencies in how to accurately determine time and distance for vehicle speed has led to examinations with varying results. A potential solution for calculating time intervals is to use frame timing contained within many digital video file's metadata, recorded with 0.000001 sec precision. This paper examines a fatal motor vehicle accident where frame timing information was used with distance measurements from reverse projection photogrammetry to calculate vehicle speed. A margin of error was then calculated based on the accuracy in …

The Potential Interference Of Body Products And Substrates To The Identification Of Ignitable Liquid Residues On Worn Clothing, Gina Guerrera, Erika Chen, Robert Powers, Brooke Weinger Kammrath

Forensic Science Publications

The question of whether deposits on clothing as well as their chemical composition are being mistaken for ignitable fluids is a concern for forensic analysts. Body products and oil secretions can have similar chemical profiles to ignitable liquid residues (ILRs) as a result of comparable chemical compounds that may be found in both sources. This study investigated whether substrates of unworn and worn clothing, with endogenous body secretions and body products could interfere with ILR analysis. Sample extraction was completed by passive headspace concentration with activated charcoal strips (ACS) and desorption with carbon disulfide followed by analysis with gas chromatography-mass …

Open-Source Tools For Dense Facial Tissue Depth Mapping (Ftdm) Of Computed Tomography Models, Terrie Simmons-Ehrhardt, Catyana Falsetti, Anthony B. Falsetti, Christopher J. Ehrhardt

Human Biology Open Access Pre-Prints

Computed tomography (CT) scans provide anthropologists with a resource to generate three- dimensional (3D) digital skeletal material to expand quantification methods and build more standardized reference collections. The ability to visualize and manipulate the bone and skin of the face simultaneously in a 3D digital environment introduces a new way for forensic facial approximation practitioners to access and study the face. Craniofacial relationships can be quantified with landmarks or with surface processing software that can quantify the geometric properties of the entire 3D facial surface. This paper describes tools for the generation of dense facial tissue depth maps (FTDMs) using …

Is Forensic Science In Danger Of Extinction?, David San Pietro, Brooke Weinger Kammrath, Peter R. De Forest

Forensic Science Publications

Observations of modern day forensic science has prompted asking the question of whether this field is in danger of extinction. Although there have undoubtedly been meaningful advancements in analytical capabilities, we have overlooked several unintended practical and philosophical consequences. This article addresses three main areas of concern: the declining role of the generalist in an era of increased specialization, the role of education in preparing the next generation of forensic scientists, and the implementation of advanced instrumentation with a focus on statistical significance and field deployable instrumentation.

The Effect Of Fabric Type And Laundering Conditions On The Detection Of Semen Stains, Tyler G. Schlagetter, Claire L. Glynn

Forensic Science Publications

There has been little research into the effect of fabric type and different laundering conditions on the ability to detect semen stains on washed fabrics. This study aimed to investigate three potential factors affecting semen identification on laundered clothing: fabric type, water temperature during washing, and whether the stain was dry at the time of washing. Following laundering, semen stains on four fabric types (cotton, polyester, denim, and wool) were examined and tested with three common methods used to detect semen; screening with an alternate light source, acid phosphatase press test, and histological staining of spermatazoa. It was determined that …

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.

Exploring Myths In Digital Forensics: Separating Science From Ritual, Gary C. Kessler, Gregory H. Carlton

Publications

Digital forensic methodology deviates significantly relative to the methods of other forensic sciences for numerous practical reasons, and it has been largely influenced by factors derived from the inception and evolution of this relatively new and rapidly changing field. Digital forensics methodology was developed more by practitioners in its early days rather than by computer scientists. This led to accepted best practices in the field that may not represent the best or, at least, tested, science. This paper explores some of these differences in the practice and evolution between digital and other forensic sciences, and recommends scientific approaches to apply …

Testing A Novel 3d Printed Radiographic Imaging Device For Use In Forensic Odontology, Tara L. Newcomb, Ann M. Bruhn, Bridget Giles, Hector M. Garcia, M. Arch, Norou Diawara

Dental Hygiene Faculty Publications

There are specific challenges related to forensic dental radiology and difficulties in aligning X-ray equipment to teeth of interest. Researchers used 3D printing to create a new device, the combined holding and aiming device (CHAD), to address the positioning limitations of current dental X-ray devices. Participants (N = 24) used the CHAD, soft dental wax, and a modified external aiming device (MEAD) to determine device preference, radiographer's efficiency, and technique errors. Each participant exposed six X-rays per device for a total of 432 X-rays scored. A significant difference was found at the 0.05 level between the three devices ( …

Forensic Science Forum, San Jose State University

Forensic Science Forum (Justice Studies)

No abstract provided.