Forensic analysts are tasked with determining the presence of ignitable liquid residue in fire debris. Analysis of fire debris allows the analyst to understand how the fire occurred. However, the presence of some substrates can potentially impact the identification of ignitable liquid residue and classification of a sample as positive or negative for the presence of ignitable liquid. Pyrolysis of building materials and furnishings (substrates) lead to background interference within the resulting chromatographic profile. To combat misclassification of a sample as positive for ignitable liquid residue, knowledge of the pyrolysis products from individual substrates is of utmost importance. However, unburned reference samples from a fire scene can be difficult to obtain. The use of a database in conjunction with the analysis of the samples can lead to a more complete analysis of fire debris. Within this research, four different burn methods (modified destruction distillation method, top heat, bottom heat, and tube furnace) were utilized in burning eight different flooring substrates (polyester, nylon, and olefin carpeting, carpet padding, vinyl flooring, laminate flooring, yellow pine, and plywood) to obtain pyrolysis/combustion product profiles. Each burn method was performed at three different burn times for a total of twelve different burns of each substrate. Standard methods, ASTM E1412-12 and ASTM E1618-14, were used in the extraction and interpretation of the laboratory burn products. Principal component analysis (PCA) was used to relate the laboratory burn results to neat ignitable liquid/substrate and large scale burn data sets. Laboratory burn data projected into the PCA space displayed that the laboratory burn data is similar to the data contained within the ILRC and Substrate databases. Differences observed within laboratory burn data projections illustrated the variability of the laboratory burn methods. The composition of the substrate dictated the pyrolysis/combustion products produced. While this research only focuses on flooring substrates, an increase in the number of different types of materials in the Substrate Database can aid analysts in identifying common pyrolysis/combustion products observed in fire debris.

An important forensic application for Y-chromosome short tandem repeats (Y-STRs) is the identification of male DNA. Since the Y-chromosome is non-recombining and most Y-STRs have slippage mutation rates on the order of 1x10-3 or lower, Y-STR commercial multiplex systems do not yet allow personal individualization. This is problematic in criminal investigations where the persons of interest include males of the same paternal line. In order to obtain discrimination among paternal male relatives, it would be necessary to use a larger number of Y-STRs or a selection of Y-loci with higher slippage mutations with the hope of encountering a germline meiotic mutation. In this study, Y-STR loci from three multiplexes were examined: an ultra-high discrimination multiplex of 14 non-core loci; Promega's PowerPlex® Y23; and a rapidly mutating 13-locus panel (mutation rates above 1x10-2). Taking the three multiplexes together provides a unique 40-locus Y-STR panel (the "Masker Set"), a powerful tool to separate closely related males. The loci were examined for discriminative slippage mutations in pairs of paternally related South Brazilian males: 99 grandfather-grandson, 103 uncle-nephew, and 140 brothers. The goal of this study was to analyze the "Masker Set" loci by: describing the characteristics and frequency of germ-line mutations; noting differences in mutation rates between and within loci; determining repeat gain and loss rates; and identifying the most informative loci to differentiate male relatives. Using the "Masker Set", pairs of male relatives were distinguished by at least one mutation 53% of the time for grandfather-grandson, 62% for uncle-nephew, and 54% for brothers. The most discriminating Y-STR loci were: DYF387S1, DYF404S1, DYS526B, DYS389II, DYS449, DYS547, DYF399S1, DYS458, DYS576, DYF403S1A, DYS508, DYS612, DYS403S1B, DYS518, and DYS627.

Pollen evidence has proven to be a powerful forensic tool to trace a suspect or item to a victim or a crime scene. This is possible because it is microscopic, abundant in nature, resistant to degradation and decay; it presents dispersal patterns that can be used to generate a 'fingerprint' within specific areas, and has illustrated a unique morphology that can be used to classify species. While the pollen grain morphology has been extensively used to characterize the specific species, not much has been investigated as pertains to the coating that surrounds the pollen grain aside from it being categorized as waste. This Master thesis focuses on the qualitative and quantitative determination of the elemental composition of this coating surrounding pollen via Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Two methodologies for sample preparation were compared: a complete digestion and analysis of (i) the entire pollen and (ii) the surrounding pollen coating alone removed from the pollen grain by Soxhlet extraction in ethanol. The goal was to discern the elemental composition of the coating and its specific elemental composition in comparison with the whole pollen grain. The results of both F-test and T-test performed for three pollen species indicated that, of the 19 elements investigated, B, Mg, Mn, K, Ti, and Cs resulted in significant differences between the whole grain and the coating alone; while Se, V, Pb, Cr, Al, and Zn can be recognized as being characteristic of the coating surrounding the pollen grain.

In some forensic disciplines various methods of extraction are used to perform analysis. Among these methods, solid phase extraction (SPE) and solid phase microextraction (SPME) are used in fields such as toxicology and explosives analysis. To enhance extraction efficiency in SPE and SPME, molecularly imprinted polymers (MIPs), which are designer polymers, can be more selective for the binding of an analyte or group of analytes that are similarly structured. Separation of analytes from complex mixtures is possible by utilizing these polymers. This may be especially useful in forensic applications where sample sizes may be small and composition may be complex. In this work, MIP solid phase microextraction fibers (MIP-SPME) were fabricated and caffeine was selectively sampled in the presence of theophylline and theobromine. Calibration studies were performed using the MIP-SPME to quantitate the concentration of caffeine in teas and coffees. MIP-SPME fibers were also prepared with 2,4-dinitrotoluene and deuterated 2,6-dinitrotoluene. Less selectivity was obtained for extraction of 2,4-DNT and 2,6-DNT in the presence of other DNT isomers. Fabricated blank polymers extracted analytes at the same response as templated polymers for both caffeine and DNT, despite expected results. MIP-SPE columns were also fabricated using deuterated 2,6-DNT to determine if changing the extraction procedure would increase extraction selectivity. Using different solvents in the extraction procedure changed the extraction performance efficiency of the MIPs due to the change in solvent polarity. All samples were analyzed using gas chromatography mass spectrometry.

NoSQL (Not only SQL) databases have been gaining some popularity over the last few years. Such big companies as Expedia, Shutterfly, MetLife, and Forbes use NoSQL databases to manage data on different projects. These databases can contain a variety of information ranging from nonproprietary data to personally identifiable information like social security numbers. Databases run the risk of cyber intrusion at all times. This paper gives a brief explanation of NoSQL and thoroughly explains a method of Incidence Response with MongoDB, a NoSQL database provider. This method involves an automated process with a new self-built software tool that analyzing MongoDB audit log's and generates an html page with indicators to show possible intrusions and activities on the instance of MongoDB. When dealing with NoSQL databases there is a lot more to consider than with the traditional RDMS's, and since there is not a lot of out of the box support forensics tools can be very helpful.

Currently, DNA profiling is the gold standard to identify an individual. However, determining body fluid origin is important in criminal investigations, offering additional information surrounding the circumstances of a crime. However, crime labs can only definitively identify blood and semen and presumptively saliva using techniques that consume time and sample and do not simultaneously identify all forensically relevant body fluids. This causes many crime labs to want to bypass body fluid identification altogether. Therefore, advances into more definitive molecular-based body fluid methods are necessary. One such technique is mRNA profiling because it provides a highly sensitive and specific approach to definitively identifying all relevant body fluids in parallel. Although advancements have been made, improvements to mRNA profiling methodologies still need to be researched such as 1) possible mRNA recovery from established DNA workflows and 2) possible integration of mRNA profiling into an upfront male DNA screening assay for triaging sexual-assault evidence likely to contain male DNA and reduce/eliminate a significant bottleneck in the standard DNA workflow of microscopic sperm identification. This study was designed to address these two issues by evaluating a novel way to recover RNA, for body fluid identification, from the waste fractions of a PrepFiler™ DNA extraction, and from the DNA extracts directly. Next, this study aimed to provide a relatively quick molecular-based approach for screening sexual-assault evidence. It involves extraction of RNA using the Dynabeads™ mRNA DIRECT™ Kit, while saving the extraction waste fractions for downstream male-DNA quantitation and STR profiling. The RNA is then used in a rapid and sensitive 1-step combined reverse transcription-HRM assay to positively detect the presence of sperm. Both non-conventional co-extraction methods successfully addressed current body fluid identification challenges and allowed for easy integration into existing workflows when single sourced, mixture and mock casework samples were analyzed.

Current methods in ignitable liquid identification and classification from fire debris rely on pattern recognition of ignitable liquids in total ion chromatograms, extracted ion profiles, and target compound comparisons, as described in American Standards for Testing and Materials E1618-10. The total ion spectra method takes advantage of the reproducibility among sample spectra from the same American Society for Testing and Materials class. It is a method that is independent of the chromatographic conditions that affect retention times of target compounds, thus aiding in the use of computer-based library searching techniques. The total ion spectrum was obtained by summing the ion intensities across all retention times. The total ion spectrum from multiple fire debris samples were combined for target factor analysis. Principal components analysis allowed the dimensions of the data matrix to be reduced prior to target factor analysis, and the number of principal components retained was based on the determination of rank by median absolute deviation. The latent variables were rotated to find new vectors (resultant vectors) that were the best possible match to spectra in a reference library of over 450 ignitable liquid spectra (test factors). The Pearson correlation between target factors and resultant vectors were used to rank the ignitable liquids in the library. Ignitable liquids with the highest correlation represented possible contributions to the sample. Posterior probabilities for the ASTM ignitable liquid classes were calculated based on the probability distribution function of the correlation values. The ASTM ignitable liquid class present in the sample set was identified based on the class with the highest posterior probability value. iv Tests included computer simulations of artificially generated total ion spectra from a combination of ignitable liquid and substrate spectra, as well as large scale burns in 20’x8’x8’ containers complete with furnishings and flooring. Computer simulations were performed for each ASTM ignitable liquid class across a range of parameters. Of the total number of total ion spectra in a data set, the percentage of samples containing an ignitable liquid was varied, as well as the percent of ignitable liquid contribution in a given total ion spectrum. Target factor analysis was them performed on the computer-generated sample set. The correlation values from target factor analysis were used to calculate posterior probabilities for each ASTM ignitable liquid class. Large scale burns were designed to test the detection capabilities of the chemometric approach to ignitable liquid detection under conditions similar to those of a structure fire. Burn conditions were controlled by adjusting the type and volume of ignitable liquid used, the fuel load, ventilation, and the elapsed time of the burn. Samples collected from the large scale burns were analyzed using passive headspace adsorption with activated charcoal strips and carbon disulfide desorption of volatiles for analysis using gas chromatography-mass spectrometry

Bioarchaeologists work to reconstruct the past using skeletal remains inside a framework influenced by archaeological data. One area, into which bioarchaeologists have sought to provide insight, is the reconstruction of physical activities through skeletal indicators. These indicators of activity include looking at skeletal changes such as development of osteoarthritis, osteon remodeling, dental modifications, cross-sectional bone geometry (CSBG) and changes to muscle attachment sites, also known as entheseal changes. The study of entheseal changes has received much attention as researchers have hypothesized that a direct correlation between muscle use and entheseal size exists. Researchers sought to interpret specific movements such as spear-throwing or kayaking by examining the muscle attachment sites involved in those movements and analyzing the robusticity of the entheses. CSBG has also been used to analyze activity levels and interpret the degree of manual labor an individual was involved in. These analyses are based on the biomechanical interpretation of bone as structure that reacts to mechanical stress by increasing bone thickness. This research tested the hypothesis that changes to entheseal size in the humerus would correlate to changes in CSBG. Entheseal changes were analyzed using two methods, the Hawkey and Merbs (1995) and Mariotti et al. (2007) methods. Both methods were analyzed in terms of their ease of use and intraobserver error rates. The Mariotti et al. (2007) method of scoring entheseal changes was found to have more instances of a significant intraobserver error rate than the Hawkey and Merbs (1995) method despite the improved photographs and more detailed descriptions provided by the authors. Both entheseal scoring methods were used to analyze the correlation between entheseal changes and CSBG in the form of the polar moment of area (J) as standardized for size (J'). CSBG has been found to have stronger correlations with mechanical use and this research sought to identify relationships between entheseal development and J' in the humerus. Entheses scored using the Mariotti et al. (2007) method were more frequently found to have a significant correlation with CSBG, while only one enthesis scored using the Hawkey and Merbs (1995) method was found to have a significant correlation (p <.05) with CSBG. This implies that the method used greatly affects the identifiable correlations between entheseal changes and CSBG. Refined methods and more research are necessary before entheseal changes can be accurately used in activity reconstruction.

The ability to extract ignitable liquids from wooden fire debris samples is an important aspect of arson investigation. A common method by which the ignitable liquids are extracted is heated passive headspace extraction, a process by which a sample is heated in a sealed container and any ignitable liquid residues present desorb from the sample and adsorb to an adsorbent present in the container. An activated charcoal strip is most often used as the adsorbent, and the recommended extraction procedure is to allow the sample to extract in an oven set at a temperature between 50 °C and 80 °C for an amount of time between 8 and 24 hours. The ignitable liquid residues can then be eluted from the adsorbent and analyzed by gas chromatography-mass spectrometry (GC-MS) to identify the type of ignitable liquid present within the sample as well as specific compounds within the ignitable liquid. The extraction procedure typically does not yield 100% of the original amount of ignitable liquid deposited on the sample. Some of the ignitable liquid residue loss can be attributed to any irreversible adsorption that occurs between the substrate and the ignitable liquid. This irreversible adsorption is not known to be a constant across different wood genera; however, the extent of irreversible adsorption may vary between differing genera of wood. The focuses of this thesis are to examine any trends in irreversible adsorption that occur in wooden substrates, to see which genera of wood presents the greatest retention of ignitable liquids, and to see if any correlation exists between the retention capabilities of a wood genus and its density. The densities were determined for a total of thirteen common wood genera, which were spiked with one of three ignitable liquids and then subjected to heated passive headspace extraction. A semi-quantitative approach was taken by comparing the abundance of specific compounds within an ignitable liquid extracted from a wood substrate to the abundance present in a diluted sample of the same ignitable liquid, allowing a comparison between different genera to be made. Ultimately, it was determined that different genera of wood do display different retention capabilities for the common ignitable liquids examined in this thesis, but there was no genus of wood which consistently demonstrated a greater retention for the ignitable liquids compared to the other genera, nor was there a genus of wood which consistently allowed for greater recovery of the ignitable liquids compared to the other genera.

Ideally a DNA profile will have high Peak Heights (PHs), balanced Peak Height Ratios (PHRs) and no drop out. However, low template DNA (LTDNA) is limited in quantity, quality or both and LTDNA profiles do not always consistently provide interpretable signal. Post-Polymerase Chain Reaction (PCR) purification is an efficient enhancement method that can be utilized to increase the amount of information in a LTDNA profile without elevated stutter, which can be common with other enhancement methods. Post-PCR purification decreases the remaining components left over from amplification, such as deoxyribonucleotide triphosphates, primers, salts, and enzymes so there is less competition during the electrokinetic injection and more DNA will go into the capillary. When post-PCR purification is used; PH’s will increase, PHRs should remain stable before and after purification and may result in recovery of alleles that previously had dropped out. Allele recovery may be the difference between an inconclusive result and an inclusion or exclusion. The efficacy of Post-PCR purification was assessed by amplifying single source DNA with both ABI AMPFℓSTR® Identifiler® (template mass down to 0.0625 ng) and Identifiler® PLUS (template mass down to 0.03125 ng) and performing post-PCR purification with Qiagen® MinElute® and Macherey-Nagel NucleoSpin®. The original amplified product and purified product were analyzed and compared and it was determined post-PCR purification reduced the primer front, increased the PHs, recovered additional alleles and did not affect the PHRs. On average the Fold Increase (FI) for Identifiler® product purified with Qiagen® MinElute® is 3.5 and the average FI for Identifiler® PLUS product purified with Qiagen® MinElute® and Macherey-Nagel NucleoSpin® is 3.2. Additionally, the stutter percentage observed in the original sample profile was compared to the purified samples to determine if purification affected the stutter percentage of Identifiler® PLUS product. It was determined at only a few alleles the amplified product was above or below the stutter percentage of purified product. The stutter percentage values for purified samples were further compared to the Identifiler® PLUS manual and only one allele’s stutter percentage is above the companies stutter cut off values. Post-PCR purification with Qiagen® MinElute® or Macherey-Nagel NucleoSpin® is a successful enhancement method to increase information of a LTDNA profile without introducing additional complications that other enhancement methods are known to do.