Footwear impression evidence in dust is often difficult to locate in ambient light and is a fragile medium that both collection and enhancement techniques can destroy or distort. The collection of footwear impression evidence always begins with non-destructive photographic techniques; however, current methods are limited to oblique lighting of the impression followed by an attempt to photograph in situ12,15,17. For the vast majority of footwear impressions, an interactive collection method, and thus a potentially destructive procedure, is subsequently carried out to gather the evidence18. Therefore, alternative non-destructive means for the preservation and enhancement of footwear impressions in dust merits further attention. Previous research performed with reflected ultraviolet (UV) photography and reflected ultraviolet imaging systems (RUVIS) has shown that there are additional non-destructive methodologies that can be applied to the search for and documentation of footwear impressions in dust34,36,37. Unfortunately, these prior studies did not include robust comparisons to traditional oblique white light, instead choosing to focus on different UV wavelengths. This study, however, seeks to evaluate the use of a RUVIS device paired with a 254 nanometer (nm) UV light source to locate 2-D footwear impressions in dust on multiple substrates against standard oblique white light techniques and assess the visibility of the impression and amount of background interference present. The optimal angle of incident UV light for each substrate was also investigated. Finally, this study applied an image enhancement technique in order to evaluate its usefulness when looking at the visibility of a footwear impression and the amount of background interference present for enhanced white light and RUVIS pictures of footwear impressions in dust. A collection of eight different substrate types was gathered for investigation, including vinyl composition tile (VCT), ceramic tile, marble tile, magazine paper, steel sheet metal, vinyl flooring, wood flooring, and carpet. Heel impressions were applied to the various substrates utilizing vacuum collected dust and normal walking pressure. Each substrate was then explored and photographed in ambient fluorescent light, oblique white light at 0, 15, 30, and 0 with the light source below the surface plane of the substrate, and 254 nm UV light at 0, 15, 30, 45, 60, 75, 90 and 0 with the light source below the surface plane of the substrate. All pictures were evaluated for clarity and visible detail of the footwear impression and the amount of background interference present, selecting for the best images within a lighting condition group. Additional intra- and intergroup comparisons were carried out to explore differences created by the various lighting conditions. Enhanced images were then created with the best scored pictures and evaluated for additional modifications in impression visibility and background interference. Photographs of footwear impressions in dust illuminated with ambient fluorescent light proved to be the most difficult conditions under which a footwear impression could be visualized. However, both oblique white light and 254 nm UV light lighting conditions showed improvements in either visualization or background dropout, or both, over ambient light conditions. An assessment of the white light and 254 nm UV light RUVIS images also demonstrated that the best angles for the light source for all substrates were oblique 0 and oblique 0 below the surface plane of the substrate lighting. It was found that white light photographs generally provided higher visibility ratings, while RUVIS 254 nm UV light photographs provided better grades for reducing background interference. Enhanced images of white light conditions provided generally poorer quality and quantity of details, while enhanced RUVIS images seemed to improve upon these areas. The use of a RUVIS to capture photographs of footwear impression evidence in dust was found to be a successful secondary non-destructive technique that can be paired with traditional oblique white light procedures. Additionally, the use of below the surface plane of the substrate lighting techniques were found to improve either visibility or background dropout, or both, over standard 0 oblique lighting, depending on the light source, and should be employed, when applicable. Finally, further investigation into digital photo-editing enhancement techniques for footwear impression evidence in dust is needed.

While ketamine is traditionally administered for anesthesia or pain management, illicit usage is often seen in forensic cases either as a recreational drug or as a tool in drug-facilitated sexual assault. Xylazine is an anesthetic agent used in veterinary medicine and does not have FDA approval for use in humans. However, it has recently been observed as a cutting agent in heroin. Post-mortem specimens present many challenges when it comes to toxicological analysis. Due to compound degradation and decomposition factors, analytes present at trace levels may be missed in blood and urine. Hair, bone, and insects have recently been investigated as alternative matrices for postmortem analysis due to their increased durability compared to more traditional matrices. However, this durability increases the difficulties in extracting and isolating compounds of interest from these matrices via traditional extraction and chromatography methods. These methods require lengthy extraction times and extensive cleanup steps in order to obtain samples suitable for analysis. Utilizing multiple instrumentation combinations, analysts are able to detect compounds at trace levels. Through the use of multidimensional chromatography, several time-consuming extraction steps can be eliminated while still retaining the ability of trace level detection and quantitation. Using Waters Oasis® HLB PRiME solid phase extraction cartridges using a methanol pH10 loading and an acetonitrile pH3 elution, a solvent extraction yielded linear dynamic ranges of 2pg/mL-1ng/mL and 5pg/mL-1ng/mL for xylazine and ketamine respectively. Rat specimens utilized in this project were treated as per an Institutional Animal Care and Use Committee (IACUC) protocol. The test rodents received an acute dosage of 2mg/mL of xylazine and 24mg/mL of ketamine approximately half an hour prior to death. The 14 test samples were placed outside directly on the ground at the Boston University Forensic Anthropology Outdoor Research Facility (Holliston, MA, U.S.A.) for a period of 6 months. A 15th rat was kept in -20°C until analysis to serve as a Time=0 sample. The outdoor samples were recovered and de-fleshed along with the Time=0 sample manually. Drug-free hair samples were donated anonymously as per Internal Review Board (IRB) protocols.

No description available.

No description available.

Analysis of trace evidence involved in sexual assault investigations holds considerable potential as a newer avenue of identification when bulk, larger evidence is not found or unreliable. Trace analysis of forensic materials involves common findings such as strands of hair, residues left on clothing, shards of paint or glass, etc. In recent research focused on the analysis of trace materials found as evidence in a sexual assault, there has been promise in condom and bottled lubricant classification based on their chemical profiles that can provide an associative link in an investigation. Few studies have considered the examination of lubricant evidence at a trace level as it may be found on a crime scene or a victim. In this study, a new protocol will be tested and established to analyze trace lubricant evidence recovered from a fabric substrate, such as underwear, after sexual assaults using Fourier transform infrared (FTIR) spectroscopy. An experiment is proposed to examine the comparison of the spectra resulting from FTIR spectroscopic analysis of bulk and trace level lubricants recovered from a cotton substrate. The resulting spectra will be compared for their similarities using multivariate statistical techniques to test the viability of the approach.

Forensic scientists and ancient DNA researchers face similar challenges with respect to genetic information acquisition and analysis. However, these communities differ in one critical aspect: while forensic science is regulated by the strict guidelines of the judicial community, ancient DNA is a research-based academic field free to explore emerging technologies as they arise. This thesis investigates the application of two methodologies, developed in ancient DNA research, to challenging extracts, in hopes of modernizing forensic models while maintaining compatibility with current standards. The first chapter focuses on blunt-end sequencing library preparation protocols previously optimized for ancient DNA specimens. Forensically-relevant extracts were converted into libraries and typed by short tandem repeats (STR) amplification. When compared to STR profiles from pre-library extracts, a significant decrease in the quality was observed, in the form of allelic drop-out, heterozygous peak imbalance and increased stutter ratios. The second chapter discusses the efficacy of two enzymatic DNA repair methods, “PreCR® Repair” and “Nelson”, on typical ancient DNA specimens. Based on endogenous sample content, fragment length variation and base misincorporation rates, some DNA repair was reported when using PreCR®. However, the use of the Nelson protocol is not recommended for use in its current state. Both sequencing library preparation and enzymatic DNA repair show potential application to forensic evidential material, but require further analyses to confirm hypotheses and observations outlined in this thesis. / Thesis / Master of Science (MSc)

A case is presented of a fatal drug interaction caused by ingestion of clozapine (Clozaril(TM)) and fluoxetine (Prozac(TM)). Clozapine is a tricyclic dibenzodiazepine derivative used as an 'atypical antipsychotic' in the treatment of severe paranoid schizophrenia. Fluoxetine is a selective serotonin reuptake inhibitor used for the treatment of major depression. Clinical studies have proven that concomitant administration of fluoxetine and clozapine produces increased plasma concentrations of clozapine and enhances clozapine's pharmacological effects due to suspected inhibition of clozapine metabolism by fluoxetine. Blood, gastric, and urine specimens were analyzed for fluoxetine by gas chromatography/mass spectrometry (GC/MS) and for clozapine by gas-liquid chromatography (GLC). Clozapine concentrations were: plasma, 4.9 μg/mL; gastric contents, 265 mg; and urine, 51.5 μg/mL. Fluoxetine concentrations were: blood, 0.7 μg/mL; gastric contents, 3.7 mg; and urine 1.6 μg/mL. Norfluoxetine concentrations were: blood, 0.6 μg/mL, and none detected in the gastric contents or urine. Analysis of the biological specimens for other drugs revealed the presence of ethanol (blood, 35 mg/dL; vitreous, 56 mg/dL; and urine 153 mg/dL) and caffeine (present in all specimens). The combination of these drugs produced lethal concentrations of clozapine and high therapeutic to toxic concentrations of fluoxetine. The deceased had pulmonary edema, visceral vascular congestion, paralytic ileus, gastroenteritis and eosinophilia. These conditions are associated with clozapine toxicity. The combined central nervous system, respiratory and cardiovascular depression of these drugs was sufficient to cause death. The death was determined to be a clozapine overdose due to a fatal drug interaction.

To date, numerous studies have examined the range of cranial thickness variation in modern humans. The purpose of this investigation is to present a new method that would be easier to replicate, and to examine sex and age variation in cranial thickness in a white sample. The method consists of excising four cranial segments from the frontal and parietal regions. The sample consists of 165 specimens collected at autopsy and 15 calvarial specimens. An increase in cranial thickness with age was observed. The results suggest that cranial thickness is not sexually dimorphic outside the onset of hyperostosis frontalis interna (HFI).

The sexual assault kit backlog in the United States has become an increasing problem over the years. Combined with the number of kits laboratories receive with how it takes to extract the deoxyribonucleic acid (DNA) from the cells, it is hard for labs to keep up with the demand. The extraction method used is called differential extraction, where the epithelial cells from the victim are separated from the sperm cells from the perpetrator into different fractions. The Temperature Controlled Differential Extraction (TCDE) method is a novel procedure developed by the Cotton Lab at the Boston University School of Medicine and designed to decrease the extraction time while performing just as well, if not better, than traditional differential extraction methods. The TCDE method uses a series of temperature-controlled enzymes to lyse cells and purify the DNA extract. The purpose of this study is to compare this TCDE method to a method implemented by QIAGEN using the EZ1® Advanced biorobot for purification, which is used in many forensic laboratories. Ten female donors each received ten cotton swabs for vaginal cell collection; cotton swabs are typically found in sexual assault kits. Each swab then received either 5ng, 25ng, or 50ng of male DNA in the form of sperm cells. One half of the swab was processed using the TCDE procedure while the other half was processed using the EZ1® method. The TCDE method results in three fractions: the Epithelial Fraction (EF), the Material Fraction (MF), and the Sperm Fraction (SF). The EZ1® protocol was modified to include the additional MF. Results of both the quantitation data as well as the electropherograms (EPGs) produced are compared between the two methods. The quantitation data for the EF shows a variable amount of female DNA recovered due to the uncontrolled amount of female epithelial cells added to the swabs from the donors. The MF shows that large amounts of female epithelial DNA remain in the fraction for the EZ1® protocol and not the TCDE protocol because of the nuclease activity of one of the enzymes. The remaining male DNA on the MF can be used to compare to a known male profile, showing that there is valuable data potentially left behind. Regarding the SF, the EZ1® protocol resulted in a higher yield of DNA than the TCDE, however, the TCDE SF electropherograms are still able to be used for comparisons against known male profiles. The TCDE protocol cuts extraction time by almost half, and the quantitation results and EPGs prove that this method has the potential to become the new standard method of differential extraction.

It is routine for the forensic scientist to obtain a genetic profile of an individual from DNA recovered from a biological stain deposited at a crime scene. In contrast, only a limited number of laboratories in the United States have the capability of performing Y-STR analysis in casework. In order to aid in facilitating the transfer of Y-STR technology to the crime laboratory community for operational use, a comparison between commercial products from three main vendors (Applied Biosystems AmpFLSTR Yfiler PCR Amplification Kit, Promega PowerPlex - Y System, Reliagene Y-PLEX 12) and two in-house Y-STR multiplexes (MPI and MPB) commenced. The main intention for this comparison was to ascertain whether commercial Y-STR kits are able to obtain a male profile from difficult samples which have been accomplished with our in-house Y-STR multiplexes; such as mixtures, post coital specimens, and environmental insults. To aid the crime laboratory community an in depth comparison of the three main commercial Y-STR kits began in hopes to glean information in circumstances where Y chromosome polymorphisms may need to be employed. For example, the ability to provide investigators with the numbers of semen donors in multiple rape cases, identification of the genetic profile of the male component in a male/female mixture, and identification of the genetic profile of the male component in an extended interval post-coital sample. The capability of typing Y-STR loci by the crime laboratory community could dramatically affect the admissibility of Y-STR evidence. Therefore, the comparison of commercially available kits is an imperative process by which the scientific community acquires the necessary information to assess the ability of a procedure to obtain reliable results, determine the conditions under which such results can be obtained and define the limitations of the procedure. Thus the information for the study could lend itself to a standard being established amongst Y-STR kits for operational use and/or the production of a new Y-STR kit. One example of how the comparison of the three main commercial Y-STR kits could directly impact a new standard being established is by examining post-coital samples and their extreme limits (>48 hrs) for each kit in which a full male genetic profile was observed and comparing it to other commercial Y-STR kit and in-house Y-STR multiplexes. This would help establish the types of cases where specific Y-STR kits would be most useful, and the parameters in which each kit is able to perform. Thus leading to the development of a highly sensitive Y-STR kit that would be more sufficient to perform with the variety of samples an operational crime laboratory would routinely analyze. The capability of typing Y-STR loci by the crime laboratory community could dramatically affect the admissibility of Y-STR evidence. Therefore, the comparison of commercially available kits is an imperative process in order to inform the forensic community of different Y-STR kits available and their performance through direct comparison using modified SWGDAM validation guidelines.