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Herrin, Amy Elizabeth. "Assessing, Modifying, and Combining Data Fields from the Virginia Office of the Chief Medical Examiner (OCME) Dataset and the Virginia Department of Forensic Science (DFS) Datasets in Order to Compare Concentrations of Selected Drugs." VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/1057.
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The Medical Examiner of Virginia (ME) dataset and the Virginia Department of Forensic Science Driving Under the Influence of Drugs (DUI) datasets were used to determine whether people have the potential to develop tolerances to diphenhydramine, cocaine, oxycodone, hydrocodone, methadone, and morphine. These datasets included the years 2000-2004 and were used to compare the concentrations of these six drugs between people who died from a drug-related cause of death (of the drug of interest) and people who were pulled over for driving under the influence. Three drug pattern groups were created to divide each of the six drug-specific datasets in order to compare concentrations between individuals with the drug alone, the drug and ethanol, or a poly pharmacy of drugs (multiple drugs). An ANOVA model was used to determine if there was an interaction effect between the source dataset (ME or DUI) and the drug pattern groups. For diphenhydramine and cocaine, an interaction was statistically significant, but for the other drugs, it was not significant. The other four drug-specific datasets showed that the DUI and ME were statistically significantly different from each other, and all of those datasets except for methadone showed that there was a statistically significant difference between at least two drug pattern groups. Showing that all of these datasets showed differences between the ME and DUI datasets did not provide sufficient evidence to suggest the development of tolerances to each of the six drugs. One exception was with methadone because there were 14 individuals that had what is defined as a "clinical 'lethal' blood concentration". These individuals provide some evidence for the possibility of developing tolerances.The main outcomes of this study include suggesting changes to make to the ME datasets and the DUI datasets with regard to the way data is kept and collected. Several problems with the fields of these datasets arose before beginning the analysis and had to be corrected. Some of the changes suggested are currently being considered at the Virginia Office of the Chief Medical Examiner as they are beginning to restructure their database.
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Ridley, Amy N. "Greening the chemistry curriculum. To embed the concepts of sustainability and environmental responsibility into the chemistry curriculum in order to equip graduates for future practises in the chemical sciences." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5345.
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Sustainability and environmental responsibility is increasingly growing in importance.
Solving the environmental problems of the planet will one day become the
responsibility of future scientists. For this reason, and with the introduction of new
chemical legislation (REACH) driving change it is essential that current students are
given a broad introduction to sustainability and environmental responsibility in order to equip them as graduates for future practice in the chemical sciences. At the University of Bradford the aim is to teach sustainability and environmental responsibility by
embedding it throughout the entire chemistry curriculum rather than teaching it in
standalone lectures. Once this has been established within chemistry it is expected that this will potentially provide a template for other areas of laboratory science within the
university.
In order to achieve the aim of this project, students, staff and potential employers tookpart in surveys with a view to inform curriculum development. Examples of best
practice were sought and used as guidance for the development of directed learning
activities for use as post lab questions and utilisation of the twelve principles of green chemistry.
Green chemistry metrics were applied to undergraduate experiments to test how well they would work in terms of ease of use, applicability and judging ¿greenness¿. It was
found that these were not very effective for use within an undergraduate laboratory due to applicability and judging ¿greenness¿, however this work highlighted other areas for
improvement. As a result of this work an environmental assessment metric system was
developed for use within an undergraduate setting.Ecoversity at the University of Bradford
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Lerer, Leonard Brian. "Forensic epidemiology : the interface between forensic science and public health." Master's thesis, University of Cape Town, 1994. http://hdl.handle.net/11427/25827.
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陳家麗 and Ka-lai Chan. "Some statistical aspects in forensic science." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31222237.
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Rinke, Caitlin. "Selective Multivariate Applications in Forensic Science." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5459.
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A 2009 report published by the National Research Council addressed the need for improvements in the field of forensic science. In the report emphasis was placed on the need for more rigorous scientific analysis within many forensic science disciplines and for established limitations and determination of error rates from statistical analysis. This research focused on multivariate statistical techniques for the analysis of spectral data obtained for multiple forensic applications which include samples from: automobile float glasses and paints, bones, metal transfers, ignitable liquids and fire debris, and organic compounds including explosives. The statistical techniques were used for two types of data analysis: classification and discrimination. Statistical methods including linear discriminant analysis and a novel soft classification method were used to provide classification of forensic samples based on a compiled library. The novel soft classification method combined three statistical steps: Principal Component Analysis (PCA), Target Factor Analysis (TFA), and Bayesian Decision Theory (BDT) to provide classification based on posterior probabilities of class membership. The posterior probabilities provide a statistical probability of classification which can aid a forensic analyst in reaching a conclusion. The second analytical approach applied nonparametric methods to provide the means for discrimination between samples. Nonparametric methods are performed as hypothesis test and do not assume normal distribution of the analytical figures of merit. The nonparametric permutation test was applied to forensic applications to determine the similarity between two samples and provide discrimination rates. Both the classification method and discrimination method were applied to data acquired from multiple instrumental methods. The instrumental methods included: Laser Induced-Breakdown Spectroscopy (LIBS), Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, and Gas Chromatography-Mass Spectrometry (GC-MS). Some of these instrumental methods are currently applied to forensic applications, such as GC-MS for the analysis of ignitable liquid and fire debris samples; while others provide new instrumental methods to areas within forensic science which currently lack instrumental analysis techniques, such as LIBS for the analysis of metal transfers. The combination of the instrumental techniques and multivariate statistical techniques is investigated in new approaches to forensic applications in this research to assist in improving the field of forensic science.Ph.D.
Doctorate
Chemistry
Sciences
Chemistry
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Chan, Ka-lai. "Some statistical aspects in forensic science /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2148241X.
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Hamby, James Edward. "Forensic firearms examination." Thesis, University of Strathclyde, 2001. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27327.
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The history of forensic firearms examination was evaluated to determine how the field has developed during the past 200 years; especially within the past 100 years. As aresult of this evaluation, some related issues were identified for study. The economic and general uses of firearms reference collections were considered as the collections represent potential security considerations within forensic laboratories. A survey was conducted to determine how firearms examiners used their collections, as well as their receptivity to augmenting the collections with modem technology such as photographs and CD-ROM's. A world-wide survey resulted in responses from 110 forensic laboratories. Examiners stated that the collections were used for training, repairing damaged evidence firearms, and demonstration purposes, and whilst they were prepared to accept modem techriology to augment their collection, stated that such augmentation could not replace the actual collection. Research was conducted to partially answer some legal issues, such as Daubert, et al., by test firing bullets from consecutively rifled barrels to obtain best known 'match' and 'non-match' bullets. To date, some 201 examiners from several countries have evaluated the bullet test sets with no errors. Further research was conducted by test firing four cartridges from 617 similar 9mm Glock pistols and microscopically evaluating the fired cartridge casings to determine if they were identifiable to themselves and not the other casings. All of the casings were identifiable to themselves and not to the other 616 casings. Advances in technology have allowed the development of automated ballistics imaging systems. Research, using the previously cited test bullets and cartridge casings, was conducted to evaluate the capability of the various systems, in conjunction with the abilities offirearms examiners. Three different automated systems were used to evaluate the bullets from the l0-barrel test results. One automated system was used to evaluate the 617 cartridge casings, again with excellent results.
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Ward, Jennifer. "Origins and development of forensic medicine and forensic science in England, 1823-1946." Thesis, n.p, 1993. http://ethos.bl.uk/.
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Wheate, Rhonda Marie Physical Environmental & Mathematical Sciences Australian Defence Force Academy UNSW. "Jury comprehension and use of forensic science." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Physical, Environmental and Mathematical Sciences, 2007. http://handle.unsw.edu.au/1959.4/38644.
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The ability of jurors and juries to comprehend and utilise scientific evidence in Australian criminal trials has been examined. From mock jury surveys relating to DNA profiling evidence, it was determined that most respondents were able to comprehend some basic and applied statistics, although their ability was in part related to their knowledge of English and their level of education. The point at which mock jurors were prepared to convict an accused solely on the basis of DNA profiling evidence was examined and found to be low compared with the strength of DNA profiling evidence commonly presented in Australian courts. Mock jurors also demonstrated the ability to process evidence that was presented in a Bayesian framework; commencing with prior odds, introducing new information and culminating in posterior odds. From a survey of Australian forensic scientists, including fraud investigators, it was found that most practitioners' concerns could be addressed by greater pre-trial consultation between experts and legal advocates. Improved knowledge within the legal profession concerning the jargon, principles, procedures, limitations and conclusions to be drawn from different scientific disciplines, prior to presenting this evidence in court, is recommended as the means by which complex evidence can be better adduced from expert witnesses and better presented to juries in criminal trials. Finally, from interviewing actual jurors in criminal trials in the Australian Capital Territory it was determined that where jurors' expectations of scientific evidence, particularly DNA profiling evidence, are not met, high levels of juror frustration and speculation may culminate in hung juries. The adversarial setting of criminal proceedings was also found to produce an environment in which jurors felt that information that would assist them in reaching a verdict was being deliberately withheld. The ability of the jury to ask questions and the allowed nature of those questions were also examined, with the resultant recommendation that juries be given more explicit information at the commencement of trials to inform them about their rights and obligations when asking questions.
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Chow, W. M. L. "Capilliary column gas chromatography in forensic science." Thesis, University of Strathclyde, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371945.
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Vidaki, Athina. "Novel uses of epigenetics in forensic science." Thesis, King's College London (University of London), 2015. http://kclpure.kcl.ac.uk/portal/en/theses/novel-uses-of-epigenetics-in-forensic-science(24bcb357-bc36-4a6e-8e66-fda2bb423015).html.
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Body fluids such as blood are amongst the most important biological evidence recovered from crime scenes. Identification of the donor can be achieved through STR profiling; however, extracting additional information regarding the tissue type or the donor’s physical appearance such as age could prove very useful in police investigations. Firstly, the performance of existing tissue-specific mRNA-based systems was assessed via collaborative exercises. All proposed methods have shown to be highly sensitive; however, issues regarding markers’ specificity, especially for the vaginal detection, were observed. Analysing complex casework samples revealed the need for interpretation guidelines and the use of a scoring system when implementing mRNA profiling in casework. It was understood that developing DNA-based testing would overcome the limitations of existing methods so the main aim of this study was to evaluate the applicability of DNA methylation profiling in forensics. Using three approaches various tissue-specific differentially methylated CpG sites in 18 different loci were evaluated by analysing various forensically relevant body fluids and tissues. As a result, a set of suitable blood- and semen-specific markers were validated using aged and mock casework samples; however, the identification of other tissues like saliva, vaginal fluid and menstrual blood seemed to be challenging. Regarding age prediction, a set of age-associated CpG sites were selected from genome-wide DNA methylation studies and the correlation of their blood methylation levels with age was assessed on two sequencing platforms. Using a subset of 16 CpG sites and taking advantage of artificial neural networks’ capabilities, age could be accurately predicted in 1,156 blood samples (mean error of 4.1 years). The applicability of the proposed prediction model was also tested by means of next generation sequencing. Although further research is required prior to implementing these results in casework, it can be concluded that epigenetics could shed light on the proposed forensic applications.
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Reidy, Lisa Jayne. "Stable isotope analysis : a new forensic science tool." Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.479310.
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Turner, Mary Anne. "Intent to aggress in forensic settings." Thesis, University of Central Lancashire, 2015. http://clok.uclan.ac.uk/11806/.
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This PhD examines the role of individual and environmental characteristics in the intent to aggress, resulting in the development of a model to understand the intent to aggress in forensic settings. Study one focused on individual characteristics of aggressors in a prison sample of adult men (n=200). The study confirmed the importance of personality traits and beliefs in engagement in aggression in forensic settings. Aggressors reported low levels of agreeableness and high neuroticism and greater aggressive supportive beliefs, although the variance explained by personality traits and beliefs was low. Study two therefore aimed to examine other factors potentially of relevance, specifically environmental factors. Staff from two Young Offender sites (n=103), one closed and one open, participated. The results confirmed the influence of the physical and social aspects of the secure setting over attitudes and responses to aggression; the more secure physical environment was found to associate with negative attitudes towards prisoners and proaggressive attitudes. Attitudes were thus found to be important factors in the response to aggression. The final study aimed to combine both individual characteristics (e.g., beliefs, fear and personality) and environmental factors in a single study using prisoners (n=427) and staff (n=78) from one category B establishment housing adult men. Examination of emotion was lacking from study one and was therefore included in study three. The results confirmed the importance of beliefs via a moderating effect of fear. Greater perceptions of the threat in the forensic setting differentiated between aggressors and those not involved in aggression. The findings of the three studies were combined with existing theoretical frameworks and suggested two different pathways to increased aggression and one for the inhibition of aggression. These three pathways are presented via the Model of Intent to Aggress in Secure Settings (MIA-SS).
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Al-Dusri, Fahad. "The effectiveness of forensic science service in the State of Kuwait in criminal investigations and proceedings : forensic science practice in Kuwait." Thesis, University of Exeter, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288002.
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Natha, Khilona. "Molecular Forensic Investigations into Animal Sexual Abuse." Master's thesis, Faculty of Health Sciences, 2021. http://hdl.handle.net/11427/32938.
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Animal sexual abuse (ASA) involves the sexual molestation of animals by humans. The identification of semen provides a legally-accepted indicator that sexual activity occurred, while forensic DNA analysis provides a lead to a potential suspect. After conducting a systematic literature review, no previous research investigating semen and/or DNA recovery from animals over time was found. Therefore, this pilot study aimed to assess the recovery of human semen and DNA from animal fur over a two-week period to establish baseline data pertaining to evidence retention in the ASA context. This pioneer study also attempted to contribute towards the development of a suitable animal fur model on which to perform experiments. Daily swabbing and testing of semen from three fur models (unpreserved baboon fur, preserved nyala hides and faux fur) showed that semen could still be detected at 14 days using standard presumptive and confirmatory tests. Although DNA degradation showed a statistically significant increase over time, forensically usable DNA profiles (≥ 12 fully typed short tandem repeat loci) were consistently obtained. There was significantly higher DNA degradation in samples from the baboon fur compared to the others, while DNA concentrations were significantly different between each fur model. These differences highlight that future research must consider the choice of fur model to best represent the animal of interest; e.g. dissected fur from a recently deceased animal would best mimic a fatal ASA case. The insight regarding the choice of animal model hopes to be of benefit for future research, which should focus on the influence of more realistic variables (e.g. movement and body heat) on semen and DNA retention on animal fur. Overall, this study successfully generated baseline data, and provides a foundation for additional research, which hopes to eventually assist in the interpretation of forensic evidence in the global burden of ASA.
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Nelson, Alexander J. "Software signature derivation from sequential digital forensic analysis." Thesis, University of California, Santa Cruz, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10140317.
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Hierarchical storage system namespaces are notorious for their immense size, which is a significant hindrance for any computer inspection. File systems for computers start with tens of thousands of files, and the Registries of Windows computers start with hundreds of thousands of cells. An analysis of a storage system, whether for digital forensics or locating old data, depends on being able to reduce the namespaces down to the features of interest. Typically, having such large volumes to analyze is seen as a challenge to identifying relevant content. However, if the origins of files can be identified—particularly dividing between software and human origins—large counts of files become a boon to profiling how a computer has been used. It becomes possible to identify software that has influenced the computer's state, which gives an important overview of storage system contents not available to date.
In this work, I apply document search to observed changes in a class of forensic artifact, cell names of the Windows Registry, to identify effects of software on storage systems. Using the search model, a system's Registry becomes a query for matching software signatures. To derive signatures, file system differential analysis is extended from between two storage system states to many sequences of states. The workflow that creates these signatures is an example of analytics on data lineage, from branching data histories. The signatures independently indicate past presence or usage of software, based on consistent creation of measurably distinct artifacts. A signature search engine is demonstrated against a machine with a selected set of applications installed and executed. The optimal search engine according to that machine is then turned against a separate corpus of machines with a set of present applications identified by several non-Registry forensic artifact sources, including the file systems, memory, and network captures. The signature search engine corroborates those findings, using only the Windows Registry.
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Lawless, Christopher James. "Helping with inquiries : theory and practice in forensic science." Thesis, Durham University, 2009. http://etheses.dur.ac.uk/2098/.
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This thesis investigates the reasoning practices of forensic scientists, with specific focus on the application of the Bayesian form of probabilistic reasoning to forensic science matters. Facilitated in part by the insights of evidence scholarship, Bayes Theorem has been advocated as an essential resource for the interpretation and evaluation of forensic evidence, and has been used to support the production of specific technologies designed to aid forensic scientists in these processes. In the course of this research I have explored the ways in which Bayesian reasoning can be regarded as a socially constructed collection of practices, despite proposals that it is simply a logical way to reason about evidence. My data are drawn from two case studies. In the first, I demonstrate how the Bayesian algorithms used for the interpretation of complex DNA profiles are themselves elaborately constructed devices necessary for the anchoring of scientific practice to forensic contexts. In the second case study, an investigation of a more generalised framework of forensic investigation known as the Case Assessment and Interpretation (CAI) model, I show how the enactment of Bayesian reasoning is dependent on a series of embodied, experiential and intersubjective knowledge-forming activities. Whilst these practices may seem to be largely independent of theoretical representations of Bayesian reasoning, they are nonetheless necessary to bring the latter into being. This is at least partially due to the ambiguities and liminalities encountered in the process of applying Bayesianism to forensic investigation, and also may result from the heavy informational demands placed on the reasoner. I argue that these practices, or 'forms of Bayes', are necessary in order to negotiate areas of ontological uncertainty. The results of this thesis therefore challenge prevailing conceptions of Bayes Theorem as a universal, immutable signifier, able to be put to work unproblematically in any substantive domain, Instead, I have been able to highlight the diverse range of practices required for 'Bayesian' reasoners to negotiate the sociomaterial contingencies exposed in the process of its application.
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Gueham, M. "Automatic classification of shoeprints for use in forensic science." Thesis, Queen's University Belfast, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.557608.
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Shoeprints are routinely left at crime scenes and are reported to be present more frequently than fingerprints. It has been reported that 35 percent of crime scenes present shoe marks that can be recovered and used as forensic evidence. During investigations, a scene of crime shoeprint can be matched against a database of known shoeprints in order to identify the brand and the model of the corresponding shoe. TIlls is known as shoeprint classification and is, currently, performed manually or using some semi-automatic systems. These current approaches are time consuming and are not very reliable. Thus, the development of automatic shoeprint classification methods would offer valuable assistance to forensic scientists. TIlls thesis addresses the task of automatic shoeprint classification and its related challenges. This includes the problem of classifying partial, noisy and/or blurred shoeprint images. The issues of invariance to geometric distortions, e.g. translations and rotations, as well as rapid classification are also considered. The thesis proposes a number of different ideas and methods for the automatic classification of distorted shoeprint images including the use of Fourier-Mellin transform, modified phase-only correlation and two-dimensional advanced correlation filters. It also investigates the use of multiple one-dimensional correlation filters and classifier combination techniques, such as algebraic rules, Decision Templates and Support Vector Machine based combiners. The experimental results suggest that the investigated correlation-based methods can offer high accuracies when classifying low quality shoeprint images while providing tolerance to geometric distortions.
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Williams, Graham Andrew. "Identification and resolution of capability gaps in forensic science." Thesis, University of Huddersfield, 2012. http://eprints.hud.ac.uk/id/eprint/17500/.
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Although forensic biology is a powerful tool in criminal investigations, there are a number of capability gaps; namely, the interpretation of low-level DNA mixtures, associating the DNA profile with a body fluid, and the issue of consent in sexual offences. A research strategy was developed that utilises whole genome amplification (WGA), messenger RNA and microRNA analysis, DNA profiling, and clothing damage analysis. An evaluation of a WGA technique – multiple displacement amplification - with and without a macromolecular crowding agent, indicated that this may be of use for DNA samples containing certain mixing ratios; however, for this to be truly of use, knowledge of the nature of the sample preanalysis is required, which is not feasible in a forensic environment. A SYBR Greenbased mRNA gene expression test was developed that was capable of distinguishing between saliva and blood by using relative quantitation on real-time PCR. However, the low specificity of the SYBR Green meant that a higher number of controls were required for this to work at forensic standard. A single channel simultaneous analytical test for DNA and microRNA was also developed, which meant that it could be possible to definitively identify the body fluid origin of a DNA profile. This represented a significant step forward in improving forensic biology capability. Reconstruction studies were carried out in response to a sexual assault case where consent was an issue. This study demonstrated that it was possible to cause significant damage to a bra without causing damage to the hook and eye fastening; thus, negating a hypothesis offered by the defence. A long term research strategy has been developed and significant progress has been made in improving the capability of the operational forensic biologist.
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Vuko, Loyiso Abongile Marvin. "Post-mortem toxicogenetics: determining the suitable of blood samples collected for routine toxicological analyses for use in subsequent genetic analyses." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29525.
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South Africa has one of the highest prevalences of drug misuse and abuse in Africa. Salt River Mortuary (Cape Town, South Africa), along with other national Forensic Pathology Service providers, receives many cases of suspected drug-related deaths. In some cases, the traditional autopsy – when viewed together with the decedent's history – is not able to indicate whether a drug-related death is accidental or suicidal in relation to altered drug metabolism. Literature has shown that this can be investigated by sequencing gene(s) encoding the implicated metabolising enzyme(s) in a postmortem genetic analysis. However, as such an analysis would normally be performed following the obtainment of postmortem toxicological results, it is imperative to investigate whether blood samples retrieved back from a toxicology laboratory would be sufficient for the said genetic analysis, despite the handling involved in the process of toxicological investigation. To this end, blood samples from 30 deceased individuals in which drug use/abuse may have contributed to death, were collected into two red-top tubes (plain), two grey-top tubes (containing sodium fluoride and potassium oxalate) and one EDTAcontaining purple-top tube (control). DNA was immediately extracted from one of each colour tube, while the duplicate red-top and grey-top tubes first underwent a process of toxicological analyses, and then underwent DNA extraction. The concentration, degradation, purity, contamination, and quality of DNA were assessed using real-time PCR, spectrophotometry, forensic DNA profiling, and Sanger sequencing. In contrast to the grey-top tubes, the results showed that the red-top tubes were most suitable for the aforementioned genetic analysis. Overall, the study not only demonstrated that postmortem genetic analysis using samples retrieved from a toxicology laboratory is possible in the local context, but also provided guidelines around the pre-analytical phase of the analysis. These results illustrate the opportunity to investigate these toxicogenetic avenues further, particularly in future expansion of services currently provided at Salt River Mortuary, which may provide families more information about circumstances of their relative’s death.
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Baptista, Lais Vicente. "Methods for improving challenging DNA profiles and molecular preservation of soft tissue samples." Thesis, University of Central Lancashire, 2018. http://clok.uclan.ac.uk/23801/.
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Degradation of DNA can lead to either poor quality, imbalanced, or even no profiles. Therefore, appropriate collection and storage methods are critical to minimize its impact. If the DNA is degraded prior to sample collection, then the degradation process can only be arrested and other methods have to be employed to try to improve the quality of the DNA profile. The major aims of this thesis were to assess alternative methods for molecular preservation of muscle tissue samples and to obtain better DNA profiles from degraded samples. Assessment of DNA degradation was undertaken using an in-house PCR assay which amplifies four amplicons from 70 bp to 384 bp. DNA degradation was evaluated in whole pig carcasses exposed to hot and humid environmental conditions. A full DNA profile could be generated for 24 hours, but some full profiles were obtained from samples taken as late as 72 hours. It was determined that when collecting tissue samples from partially decomposed bodies, those should be preferentially from the surface of the body in touch with the ground, as the results show that DNA persistence is improved. In order to compare field and laboratory degradation patterns, muscle tissue samples were incubated in the laboratory at 25 °C and 37 °C. The persistence of DNA was increased when compared to field, most likely due to the lack of insect activity and of variations in temperature and humidity. Partially degraded muscle samples were preserved with 96% ethanol, cell lysis solution, or cell lysis solution with 1% sodium azide, which had been stored at room temperature for seven years. Samples were re-extracted to assess the long-term efficacy of these storage solutions. The results show that ethanol and cell lysis solution with 1% sodium azide were successful in preserving DNA for this period. Fresh muscle tissue samples were stored at 25 °C and 37 °C for up to 42 days using vodka and 37.5% ethanol as preservatives. Complete amplification profiles were obtained up to the last time point from samples that had any preservative solution, while samples left untreated had dropouts after 14 days. It is recommended that the use of drinking ethanol should be considered in situations where the stock of absolute ethanol is limited. The possibility of using vacuum for preservation was tested on fresh muscle tissue samples incubated at 25 °C and 37 °C. The results show that even if there was a limited amount of air inside the storage bag, and not complete vacuum, DNA persistence was enhanced when compared to samples incubated at the same conditions in plastic tubes. Some approaches were attempted to improve degraded DNA profiles. First, degraded DNA was selectively extracted from agarose gels to manipulate the proportion of longer and smaller DNA fragments present. Despite promising preliminary results, this technique showed no usefulness in improving DNA profiles. Purification columns were used with the same aim, but when comparing the original sample with the processed samples, the best results obtained were of equivalence. As an alternative approach, a protocol of DNA Capture was developed in an attempt to preferentially extract the fragments to be analysed in a degraded DNA sample in equal amounts. Whilst the DNA capture method worked in preliminary experiments, it was not applied to degraded profiles. The results obtained have allowed recommendations around collection (i.e. how long samples could be viable for DNA analysis) and storage to be refined. Attempts to rebalance already degraded profiles were not successful. Future field experiments planned as a follow up to the work presented involve testing collection methods and the effectiveness of vacuum body bags.
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Alenizi, Mohammad Abdullah. "The application of DNA profiling to the identification of victims in the Gulf War (1990-1991)." Thesis, University of Central Lancashire, 2009. http://clok.uclan.ac.uk/20370/.
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This project was designed and developed in response to the need to improve the methodology employed in the DNA profiling of the Kuwaiti victims of the First Gulf War (1990-1991). The main challenges have involved developing the methodology in an attempt to increase the DNA recovery from the skeletal remains and also assess the preservation of DNA in the remains. In addition, work was undertaken to assess two commercial STR amplification kits, the Identifiler® and MiniFilerTM, to establish allele frequency databases for use in Kuwait and to assess the concordance of the two kits. In order to assess the methodology for DNA extraction and prediction of DNA preservation two sources of materials were used: simulated casework samples and actual casework samples. To obtain simulated casework samples, bones from sheep and teeth from human were buried at three different sites within Kuwait. These were sampled over a period of 60 weeks. In addition, samples from the femur and humerus of 25 individuals who were killed during the Gulf War, but had not yet been identified, were taken for analysis. These were exhumed from five gravesites, three in Iraq and two in Kuwait. Previous attempts to generate DNA profiles from the samples had failed. Different extractions protocols and purification methods were assessed including: a phenol:chloroform-based extraction; the GENECLEAN® Kit (Obiogene); QlAquick Gel Extraction kit (Qiagen); the QIAamp DNA Blood Maxi kit (Qiagen), using a protocol based on Davoren et al (2007); and a modified silica-based extraction using the DNeasy® Blood and Tissue Kit (Qiagen). PCR amplification of the extracts and the real-time quantification results showed that the modification of a silica-based method, using the Qiagen DNeasy® kit, was successful in removing inhibitors that were present in the extracts and obtained with all the other extraction methods. This allowed the successful profiling of 19 out of the 25 samples that had previously failed. In an attempt to further improve the DNA extraction efficiency, the effect of Nphenacylthiazolium bromide (PTB) was assessed. PTB has been reported previously to improve DNA extraction from ancient DNA samples (Paabo, 1989; Poinar et al., 1998) by releasing DNA that has become cross-linked with proteins. In this study, the effect of PTB, while statistically significant when used with samples from some sites, was minimal. The power of different methods to allow an effective system of triage (sorting of samples based on the likelihood of successful analysis) was examined. Three parameters were assessed: gross morphology, histology, and chemical status of the bones were compared with the amount and quality of DNA that was recovered from different samples. The simulated casework samples displayed only minor changes in gross morphology and histology over the period of the study, whereas the casework samples displayed varying degrees of change. The samples from Iraqi sites generally displayed good morphological and histological preservation. In contrast, the samples from the two sites within Kuwait displayed an almost complete lack of histological features and changes (pitting/cracks) to the surface. The morphological and histological preservation correlated closely with the success rate when extracting DNA from casework samples that were buried in Iraq and Kuwait. Nitrogen content in all samples was very similar and the results showed that it was not a useful indicator of preservation. The MiniFilertM (Applied Biosystems) is designed for the analysis of degraded DNA. Before applying this to casework, it is important to carry out a concordance study in order to ensure the results with the MiniFilerTM are comparable to the Identifiler® (Applied Biosystems) DNA profiles. The reference database with relatives' DNA profiles are all generated using Identifiler®. To assess the concordance, the MiniFilerTM profiles from 200 unrelated Kuwaiti samples were compared to Identifiler® profiles. Concordance was observed for 99.875% of the compared loci (1598 of 1600). The two discordant profiles displayed allelic dropout: one at the Dl 35317 locus due to non-amplification of allele 10 in the MiniFilerTM profile, and one at the D18S51 locus due to nonamplification of allele 18 in the Identifiler® profile. Finally, since the population of Kuwait is heterogeneous, with a strong tribal system, the possibility of subpopulation effect within the Kuwaiti population was examined. Allele frequencies for the 15 STR loci included in Identifiler® kit were ascertained in a sample population of 502 unrelated Kuwaiti individuals. The results were compared with 6 different populations. The Kuwaiti population was very similar to neighboring Iraqi and Saudi populations. These data are now used in casework undertaken in Kuwait, to calculate the statistical significance of matching DNA profiles (the results of the reference database work are included in Appendix 1 rather than in the main body of the thesis).
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Zahra, Nathalie. "The development of PCR internal controls (PICs) for forensic DNA analysis." Thesis, University of Central Lancashire, 2009. http://clok.uclan.ac.uk/20515/.
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Proper interpretation of DNA profiles depends on the quality of the DNA samples, the amplification efficiency and the success of post-PCR processing. Chemicals associated with forensic samples can affect the amplification process while random errors occurring during pipetting and electrokinetic injection can cause variability. This can lead to either a reduced signal or lack of DNA profiles. As recommended by the SWGDAM, laboratories carrying out DNA profiling have to adopt standardise and validate procedures, which lead to high levels of quality assurance and control. During amplification, monitoring is restricted to the use of exogenous controls, which are unable to identify issues associated with individual samples. To address this limitation, four PCR Internal Controls (PJC5) i.e. two Internal Amplification Controls (IACs) and two Internal Non-Amplifiable Control (INAC5), to be used with the AmpFtSTR® SGM Plus® kit were developed. The IACs (90 bp and 410 bp) and INACs (80 bp and 380 bp) fragments were generated from the plasmid pBR322 and added along with human DNA in a 12.5 gl PCR volume. During the reaction the IAC% and 1AC 41 0 are amplified non-competitively with ROX labelled primers, while the pre-labelled INAC80 and 1NAC 380 were not involved with the amplification process. Both sets of fragments were detected as red peaks on the electropherogram flanking the human DNA profile. To study the behaviour of the markers within the system and their effect on the performance and sensitivity of the assay, the PICs were used during the amplification of human DNA of different quantity and quality and with the addition of three common inhibitors. Initial experiments involving the individual development of the fragments showed that both the INACs and IACs can be successfully applied to the amplification of human DNA with SGM Plus® reaction under optimised conditions, without significantly impacting the quality of human DNA profile. As the INACs fragments are designed not to amplify during the reaction, they gave a stable signal that can be used to monitor the post-PCR sample processing. The peak height ratios (PHRs) of human DNA with that of the LNAC8 0 or 1NAC380 can also be used to normalise the signal and assess the amplification efficiency of human DNA samples within replicates of the same sample run under the same conditions. The JACs on the other hand gave more information on the process of the PCR. They were able to monitor changes in the amplification efficiency and detect presence of inhibitors with a minimum inhibitory concentration closer to the SGM Plus® as compared to the Quantifiler® WC system. The IAC90 and 1AC410 ratios were also used to distinguish between partial profiles obtained from degraded DNA and those resulting from partial inhibition. Combining the two sets of fragments together with the amplification of human DNA needed further reaction optimisation, involving the addition of dNTPs and MgCl2. The presence of PICs provided information on the amplification performance and post-PCR processing and can assist with the interpretation of human DNA profiles. The position of the fragments also allowed PICs to be used as sizing standard. Compared to the GSTh 500 ROXTM size standard, PICs showed a slightly lower sizing precision, with standard deviations lower than 0.3 bp. Even though this resulted in allelic bins higher than 1 bp limit for 99.7% confidence, all samples sized with PICs were correctly genotyped. The addition of PICs would be a valuable tool, in particular, for the analysis of compromised DNA. In particular it would be useful when analysing DNA recovered from skeletal remains, which are prone to accumulation of PCR inhibitors and DNA degradation.
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Hassan, Nur Haliza Binti. "Evaluation of insertion/deletion polymorphisms (INDELs) applied to forensic casework in Malaysia." Thesis, University of Central Lancashire, 2017. http://clok.uclan.ac.uk/20673/.
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In Malaysia, as well as other forensic laboratories in tropical climates many of the crime scene samples received at the forensic laboratory are less than ideal. They are often present low amounts and/or degraded due to environmental exposure to high temperatures, sun and humidity for days or even months. STR analysis is widely accepted by forensic community, but sometimes this technique gives unreliable results when profiling degraded samples as the amplicons size are relatively larger (100 bp to 450 bp). While, miniSTR is a reduced size of STR amplicons which enables higher recovery of information from degraded samples, but only a few loci are amplified and allele drop out still may occur, as the amplicons are up to 200 bp. The percentage of recovery DNA profile from degraded DNA using mtDNA is much higher due to its present in cells at a much higher copy number than the nuclear DNA. However, the major drawback for mtDNA is labour intensive and has a low information value (i.e. it is not highly discriminating). Insertion/deletion polymorphisms (INDELs) are relatively new class of a DNA marker used in forensic casework; used most commonly as a supplementary method to STR (Short Tandem Repeat) based typing. INDELs, like SNPs (Single Nucleotide Polymorphisms), are particularly useful for the analysis of highly degraded DNA as the amplicon sizes are typically below 160 bp; they can also be valuable as an additional tool to help resolve kinship cases, with the advantage over STRs that do not have high mutation rates. INDELs have an advantage over SNPs in that they are length polymorphisms and so can be analysed by simply measuring the length of the allele(s). The Qiagen Investigator DIPplex® kit is currently one of two commercially available kits for the amplification of INDEL polymorphisms; it amplifies 30 biallellic INDEL loci and the amelogenin locus. The primers used are fluorescence labelled with 6-FAM, BTG, BTY and BTR. This technique is robust, relatively simple, and the results are analysed using the same capillary electrophoresis equipment and software as used for STR typing. The INDEL markers have simple biallelic structure and combine the advantages of STR and SNP assays. This study has established that the INDEL technique, using the Investigator® DIPplex PCR kit, is a simple, informative and sensitive approach for the typing of degraded DNA, as compared to STRs and SNPs. In this research, allele frequencies for 30 autosomal INDEL loci were studied in 500 unrelated individuals (100 each) from Malay, Malay-Chinese (M-Chinese), Malay-Indian (M-Indians), Iban and Bidayuh. The PCR amplification used the Qiagen Investigator® DIPplex kit. These population groups represent the majority of the population in Malaysia. No significant departure from Hardy Weinberg Equilibrium (HWE) expectations were observed for most of the INDEL loci analyzed (p-value >0.05) on the Malaysian population samples. The exceptions were HLD101 for Malay (p = 0.0009), HLD133 for M-Indian (p=0.005), HLD125 for Iban (p=0.028) and HLD93 for Bidayuh (p = 0.014). However, when the Bonferroni correction for multiple testing performed on the population samples, none of the previous p-values was significant. There were no Malaysian population studies was carried out using the Qiagen Investigator® Investigator DIPplex kit at the time of the research. This INDEL assay have undergo an extensive valdidation process and novelty report of the allele frequencies of INDELs would serve as reference database for individual identification in the Malaysian population in the future. Even the match probability of the STR is higher, INDEL still gives an acceptable value for forensic identification; e.g. linking different pieces of evidence or re-association of body parts in the case of human identification. Biological samples received in Malaysia forensic laboratory have often been exposed to unfavourable environmental conditions. This can lead to DNA degradation and end up in incomplete DNA profiles. It is difficult to distinguish between low template DNA that are producing no or partial profiles because of DNA degradation and those that produce no or incomplete profile because of PCR inhibition. Even though real-time PCR methods are available for quantification and detection of PCR inhibitors, the information received is limited as real-time PCR targets amplicons that are much smaller than those typically targeted in forensic analysis. To gain more information on the quality of extracted DNA, a new multiplex PCR assay comprising a Mini 4-plex targeting amplicons of 50 base pairs (bp), 70 bp, 112 bp and 154 bp along with two Internal Amplification Controls (IACs) of 90 bp and 170 bp was developed. The primers were redesigned from a 4 plex & IACs system developed by previous PhD UCLan students. This multiplex was optimised so that it worked efficiently on DNA template as low as 0.009 ng, which highlighted the strength of the Mini 4-plex system. The IACs were effective in detecting PCR inhibitors. The Mini 4-plex system (Mini 4-plex & IACs) was demonstrated to be an effective tool for identifying degraded and inhibited samples, which could be used to triage forensic samples in a casework laboratory. Therefore, this study has led to the improvement of new and novel markers assessing DNA degradation and PCR inhibition on forensic samples. This will demonstrate the compatibility with forensic laboratory workflows. The need of this Mini 4-plex assay in forensic laboratory can reduce time and cost of DNA analysis. Besides it will contribute to a good management samples, where after being assessed the samples can be decided to analyse using appropriate kit (e.g. miniFiler or INDEL). Indirectly, this will increase the quality of the sample itself. In order to increase the power of a 15 Mini-INDEL multiplex, which was developed earlier by UCLan PhD student, a total of 9 autosomal INDEL markers that are not part of the Qiagen Investigator DIPplex® kit were selected and redesigned from (Pereira et al. 2009). In this study a simple and sensitive INDEL multiplex was successfully developed for human identification. However, the discrimination power is still low when compared to STR systems, but has potential value when analysing highly degraded material. By combining the 15 Mini-INDELs and 9 Mini-INDELs allele frequency data, it will give beneficial by increasing the match probability values in future analysis.
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Afolabi, Olatunde Abimbola. "An evaluation of genetic markers for forensic identification of human body fluids." Thesis, University of Central Lancashire, 2017. http://clok.uclan.ac.uk/20739/.
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Body fluids are commonly recovered from crime scenes by forensic investigators and their identification are necessary part of forensic casework study. Current body fluid identification techniques rely on enzymatic tests, which have limited sensitivity and specificity, they require large amount of template, use separate assays for various body fluids, and are prone to contamination. Various genes are expressed in different body fluids that could be used as genetic markers for body fluid identification, and are used in forensic investigations. The aim of this study was to use mRNA markers to identify human body fluids, which included blood, semen, saliva, vaginal secretion and menstrual blood. Initially, ten reference genes (UCE, TEF, GAPDH, 18S rRNA, ACTB, B2M, B-Actin, OAZ1, RPS 29 and S15) were studied to establish an appropriate reference gene in body fluid identification. These are constitutive genes used for normalisation of gene expression data and control of variations in experiments. qRT-PCR efficiency, sensitivity and limit of detection (LOD) were investigated using SYBR Green and Taqman probes. The results of the SYBR Green efficiency test experiment displayed five markers, UCE, TEF, ACTB, B2M, and RPS29 with 90-110% efficiency with a slope -3.33 ± 10%. Subsequently, Taqman probes were designed for the five markers and then used for the Taqman probe experiment. Reference gene stability test was carried out on body fluid samples stored up to 6 months at room temperature using the designed Taqman probe assays. The results established ACTB and UCE as best candidate reference gene markers in this study as both were most stable in samples stored for 6 months. Furthermore, to identify each of the five body fluids, thirty-two (32) body fluid specific mRNA markers were evaluated, optimised and validated. The experiment was initially carried out with non-fluorescent makers to determine the specificity of the markers. These were analysed using agarose gel electrophoresis. Further optimization was then carried out using fluorescently labelled markers. This was done in five separate multiplexes for each body fluid; –semen-plex, saliva-plex, vaginal secretion-plex, menstrual blood-plex and blood-plex. An attempt was made to combine all the five-separate multiplex into a single multiplex. All body fluids were identified unambiguously with no cross-reactions of non-target body fluids using the combined multiplex assays. Following further evaluation and validation tests, a total of 14 markers were selected and a capillary electrophoresis (CE) based, multiplex assay was developed to identify blood, saliva, semen and vaginal secretion samples simultaneously. The markers in the developed multiplex assay included ALAS2 and PF4 (blood), STATH and HTN3 (saliva), PRM1, TGM4, MSMB, NKX3-1 (semen), ACTB and UCE (reference genes), CRYP2B7P1, SFTA2, MUC4 and L. crispatus (vaginal secretion). Extensive validation, which include sensitivity, specificity, reduced volume reactions, degradation, reproducibility, mixtures, cycle number and mastermix, was carried out in accordance with the guidelines detailed in Scientific Working Group in DNA Analysis (SWGDAM). The 14-marker CE-based assay displayed high specificity and sensitivity. Each body fluid was detected down to 1:3000 dilution of mRNA except vaginal secretion that was detected down to 1:1500 dilutions of sensitivity. Specificity experiments showed no cross reactions of the assay with non-target body fluids. Reproducibility study displayed similar results reported from an independent laboratory. All body fluids exposed to environmental insult were identified up to at least day 30 of 51, with blood being identified up to day 51. In the mixture study, all body fluids were identified unambiguously using the developed multiplex assay. In conclusion, the results of this study have led to the development of a new and novel capillary electrophoresis-based mRNA marker assay for forensic body fluid identification, demonstrating its compatibility with forensic laboratory workflows. The use of this assay to profile forensic casework samples for body fluid identification would be a future application of this work.
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Tse, Wai-hin Kenneth, and 謝維軒. "Forensic analysis using FAT32 file cluster allocation patterns." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46605733.
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Saks, Michael J., Thomas Albright, Thomas L. Bohan, Barbara E. Bierer, C. Michael Bowers, Mary A. Bush, Peter J. Bush, et al. "Forensic bitemark identification: weak foundations, exaggerated claims." OXFORD UNIV PRESS, 2016. http://hdl.handle.net/10150/622734.
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Several forensic sciences, especially of the pattern-matching kind, are increasingly seen to lack the scientific foundation needed to justify continuing admission as trial evidence. Indeed, several have been abolished in the recent past. A likely next candidate for elimination is bitemark identification. A number of DNA exonerations have occurred in recent years for individuals convicted based on erroneous bitemark identifications. Intense scientific and legal scrutiny has resulted. An important National Academies review found little scientific support for the field. The Texas Forensic Science Commission recently recommended a moratorium on the admission of bitemark expert testimony. The California Supreme Court has a case before it that could start a national dismantling of forensic odontology. This article describes the (legal) basis for the rise of bitemark identification and the (scientific) basis for its impending fall. The article explains the general logic of forensic identification, the claims of bitemark identification, and reviews relevant empirical research on bitemark identification-highlighting both the lack of research and the lack of support provided by what research does exist. The rise and possible fall of bitemark identification evidence has broader implications-highlighting the weak scientific culture of forensic science and the law's difficulty in evaluating and responding to unreliable and unscientific evidence.
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Churinsky, Candace Renee. "Characterization of carbon electrode surfaces development of biosensors for forensic DNA applications." Thesis, Boston University, 2013. https://hdl.handle.net/2144/21139.
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Thesis (M.S.F.S) PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.Quantitative polymerase chain reaction (qPCR) techniques are currently used to quantify samples containing deoxyribonucleic acid (DNA) in forensic analyses. This technology can provide valuable information to an analyst regarding the amount of DNA present but lacks the ability to determine the quality of the sample. Electrochemistry-based biosensors that utilize screen-printed electrodes may provide a method to determine the number of DNA molecules and the length of those molecules in a single assay. This work aimed to create a biosensor by electrostatically loading TPOX oligonucleotides onto a carbon screen-printed electrode for the purpose of quantifying genomic DNA. Electrochemical signal was obtained via the indicating molecule bis-benzimide H33258, which preferentially interacts with double-stranded DNA and would indicate a hybridization event. Cyclic voltammetry was chosen to measure the current signal; peaks obtained using this technique can be analyzed with the Randles-Sevčik equation, which relates current signal with concentration of the target species. A large amount of signal variation and background charging current was observed when H33258 was used as the redox probe. This led to a study of the surface characteristics of the carbon electrodes themselves (i.e. effective surface area) by utilizing the reversible and well-characterized redox couple hexaammine ruthenium. The effect of electrode activation at high anodic potentials was also studied. Though highly recommended in the literature, activation of the carbon surface caused effective surface area and charging current to increase. While a larger electro-active surface is often desirable, the high background current generated when activation is used within the protocol can mask the signal of interest. Due to the low signal-to-noise ratio and inability to reuse the carbon electrode, it was concluded that carbon screen printed electrodes are not optimal forensic DNA biosensors.
2031-01-01
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Day, Donnah Marie. "Development of immature blowflies and their application to forensic science." Access electronically, 2006. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060731.111615/index.html.
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McEwen, Gordon John. "Colour image processing for textile fibre matching in forensic science." Thesis, Queen's University Belfast, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336101.
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Hartshorne, A. W. "The characterisation of single fibres in forensic science by microspectrophotometry." Thesis, Heriot-Watt University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380723.
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Valiér, Claire Elizabeth. "Looking for the criminal : forensic science, criminal investigation, and subjectivity." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620966.
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Apple, Kendra Kea. "Inquiry-based science for high school students: a forensic unit." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2585/.
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This project constitutes an instructional unit for honors biology that involves the use of science in the field of criminal investigation and forensics. Before beginning the unit, the learners should have mastered basic laboratory skills, including use of the microscope. They should also have an understanding of the basic structure and function of DNA and its role in heredity and protein synthesis. The standard time frame is 24 days with 70-minute periods, but can be easily adjusted to meet classroom needs. Several instructional strategies enhance student learning and make science fun. The unit is inquiry-driven and activity-based. Students are surprised by the crime, gather and analyze evidence, and work towards proposing an explanation. This real world problem involves the use of cooperative learning and a variety of assessment techniques.
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Corbin, George. "The Google Chrome operating system forensic artifacts." Thesis, Utica College, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1571599.
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The increased popularity of Google Chromebooks due to their ease of use, security features and low price have contributed to explosive growth in terms of their market share in the personal computing marketplace. This growing market share will result in Chromebooks becoming part of new and ongoing forensic investigations. It is important for forensic investigators to have a strong understanding of the forensic artifacts found on a Google Chromebook. The investigators need to know what these artifacts mean and how to acquire them. A Google Chromebook uses the Google Chrome Operating System for its operating system. The purpose for the research was to begin developing the necessary art in support of forensic examiners tasked with investigating Google Chromebooks and the data they use.
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Soobhany, Ahmad Ryad. "Image source identification and characterisation for forensic analysis." Thesis, Keele University, 2013. http://eprints.keele.ac.uk/2301/.
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Digital imaging devices, such as digital cameras or mobile phones, are prevalent in society. The images created by these devices can be used in the commission of crime. Source device identification is an emerging research area and involves the identification of artefacts that are left behind in an image by the camera pipeline. These artefacts can be used as digital signatures to identify the source device forensically. The type of digital signature considered in this thesis is the Sensor Pattern Noise (SPN), which consists mainly of the PRNU (Photo Response Non-Uniformity) of the imaging device. The PRNU is unique to each individual sensor, which can be extracted traditionally with a wavelet denoising filter and enhanced to attenuate unwanted artefacts. This thesis proposes a novel method to extract the PRNU of a digital image by using Singular Value Decomposition (SVD) to extract the digital signature. The extraction of the PRNU is performed using the homomorphic filtering technique, where the inherently nonlinear PRNU is transformed into an additive noise. The range of the energy of the PRNU is estimated, which makes it easier to separate from other polluting components to obtain a cleaner signature, as compared to extracting all the high frequency signals from an image. The image is decomposed by using SVD, which separates the image into ranks of descending order of energies. The estimated energy range of the PRNU is used to obtain the interesting ranks that are utilised to form part of the digital signature. A case study of an existing image analyser platform was performed by investigating its identification and classification results. The SVD based extraction method was tested by extracting image signatures from camera phones. The results of the experiments show that it is possible to determine the source device of digital images.
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Smith, Lisa L. "The role of pre-trial attitudes about forensic science evidence : developing and testing a forensic evidence evaluation bias scale." Thesis, University of Leicester, 2011. http://hdl.handle.net/2381/9896.
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The unique decision making task entrusted to lay juries in adversarial legal systems has attracted the attention of legal psychologists for decades, but more recently technological advances in forensic science have highlighted the importance of understanding how jurors perceive this often ambiguous and complicated type of evidence. This thesis begins by investigating the forensic awareness of lay participants, and the ability of mock jurors to discriminate between varying probative values of forensic evidence. The findings suggest that the perception of weak forensic evidence is affected by contextual information, and there was wide disagreement among participants about the probative value of weak evidence. In an effort to explain the variance in perceived evidence strength, a measure of pre-trial attitudes about forensic science was developed (the Forensic Evidence Evaluation Bias Scale – FEEBS) and administered to 446 participants ranging from students, to jury eligible members of the public, to actual jury venire persons. The results of exploratory and confirmatory factor analyses identified two distinct clusters of attitudes measured by the FEEBS, which correspond conceptually to the hypothesised juror beliefs described in the CSI Effect literature. These attitudes were found to have a significant indirect effect on verdict preference, for trial vignettes describing murder, robbery, and sexual assault scenarios containing weak (or absent) forensic DNA evidence. The implications of these findings for voir dire hearings are discussed, with reference to the cognitive models of juror decision making and the CSI Effect literature.
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Kruger, Jaco-Louis. "Digital forensic readiness for IOT devices." Diss., University of Pretoria, 2019. http://hdl.handle.net/2263/73385.
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The Internet of Things (IoT) has evolved to be an important part of modern society. IoT devices can be found in several environments such as smart homes, transportation, the health sector, smart cities and even facilitates automation in organisations. The increasing dependence on IoT devices increases the possibility of security incidents in the physical or cyber environment. Traditional methods of digital forensic (DF) investigations are not always applicable to IoT devices due to their limited data processing resources. A possible solution for conducting forensic investigations on IoT devices is to utilise a proactive approach known as digital forensic readiness (DFR).
This dissertation firstly aims to conduct a thorough review of the available literature in the current body of knowledge to identify a clear process that can be followed to implement DFR tailored for IoT devices. This dissertation then formulates requirements for DFR in IoT based on existing forensic techniques. The requirements for DFR in IoT give rise to the development of a model for DFR in IoT, which is then implemented in a prototype for IoT devices. The prototype is subsequently tested and evaluated on IoT devices that conduct proactive DFR in a simulation of a smart home system. Finally, the dissertation illustrates the feasibility of the DFR processes for IoT and serves as a basis for future research with regards to DFR in IoT. This dissertation will impact future research with regards to developing a standard for DFR in IoT.Dissertation (MSc)--University of Pretoria, 2019.
Computer Science
MSc
Unrestricted
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King, Sherria Nicole. "Stress and Job Satisfaction in Career College Criminal Justice Department Heads." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5490.
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There has been a significant amount of research on the impact of stress and job satisfaction amongst employees in a multitude of professional settings, including the criminal justice and higher education field. Yet, information on criminal justice professionals who work in more untraditional types of higher education institutions, such as career colleges, was lacking. The purpose of this quantitative research study was to examine whether there is a significant relationship between stress, job satisfaction, and being employed as a criminal justice department head within a career college institution and compare whether heads of other departments within career college institutions differ in terms of these relationships. Selye's stress model and Spector's model of job satisfaction were used as the theoretical framework. Nonexperimental quantitative survey data were collected from 77 department heads and instructors who worked in career college institutions. Participants were selected using a nonprobability convenience sampling procedure. The data were evaluated using discriminant analysis. The overall results showed no significant differences in the relationship of stress and job satisfaction between criminal justice department heads and instructors and their counterparts in other academic departments. Further in-depth research regarding the individual work-related experiences of these professionals could be beneficial in gaining a holistic understanding of criminal justice professionals who transition to higher education. With more knowledge, employers within this sector of higher education may be able to better evaluate institutional practices and develop more effective intervention and training programs aimed at improving retention and job satisfaction, as well as, igniting a change in the negative image that is often times associated with career college institutions.
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Schultz, John S. "Offline forensic analysis of Microsoft Windows XP physical memory." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2006. http://library.nps.navy.mil/uhtbin/hyperion/06Sep%5FSchultz.pdf.
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Thesis (M.S. in Computer Science)--Naval Postgraduate School, September 2006.Thesis Advisor(s): Chris Eagle. "September 2006." Includes bibliographical references (p. 73-74). Also available in print.
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Kinchla, Brendan. "Forensic recovery of evidence from deleted VMware vSphere Hypervisor virtual machines." Thesis, Utica College, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1587159.
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The purpose of this research was to analyze the potential for recovering evidence from deleted VMware vSphere Hypervisor (ESXi) virtual machines (VMs). There exists an absence of scholarly research on the topic of deleted VM forensic recovery. Research dedicated to forensic recovery of ESXi VMs and VMware’s VM file system (VMFS) is nearly non -existent. This paper examined techniques to recover deleted ESXi VMs to a state where examination for forensic artifacts of user activity can occur. The paper examined the disk-provisioning methods for allocation of virtual disk files and the challenges for forensic recovery associated with each disk-provisioning type. The research determined that the two thick-provisioned virtual disk types provided the best opportunity for complete recovery, while certain characteristics of thin-provisioned virtual disk files made them less likely to recover in their entirety. Fragmentation of virtual disk files presented the greatest challenge for recovery of deleted VMs. Testing of alternate hypotheses attempting to reduce the likelihood of fragmentation within the virtual disk file met with mixed results, leaving fragmentation of virtual disk files as a significant challenge to successful VM recovery. The paper examined the techniques for recovering deleted files from VMFS volumes. Due to a lack of forensic tools with the ability to interpret the VMFS filesystem, forensic recovery focused on data stream searching through the VMFS volume image and file carving from consecutive disk sectors. This method proved to be inefficient, but ultimately successful in most of the test cases.
Keywords: Cybersecurity, Professor Cynthia Gonnella, virtualization, VMDK.
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Sholl, Sarah A. "The investigation of the relationship of familial factors in ear prints and photographs for the purposes of human identification." Thesis, University of Glasgow, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272845.
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Wysocki, Michael Peter. "The re-examination of extant human skeletal remains from excavated earlier Neolithic long barrows and chambered tombs in southern Britain." Thesis, University of Central Lancashire, 2010. http://clok.uclan.ac.uk/20363/.
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A series of seven published peer-reviewed papers and reports are presented. The body of work to be considered is concerned with the reexamination of previously excavated Earlier Neolithic human remains from Southern Britain. These form the subject of a Synoptic Overview. The Synoptic Overview places the papers within the context of academic debate and knowledge as it stood in the mid 1980s and 1990s. The background events surrounding the writing of the papers and the extent of the author's involvement in collaborative papers are detailed. The papers present new information concerning Ecirlier Neolithic mortuary assemblages and their formation and subsequent taphonomic histories, new information concerning the extent of interpersonal violence in the Earlier Neolithic and new chronological data and interpretations. The contribution to knowledge of each of the papers is summarised and critically reflected on.
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Birdsall, Nathan. "Intimate partner violence victimology : factors affecting victim engagement with the police and criminal justice system." Thesis, University of Central Lancashire, 2018. http://clok.uclan.ac.uk/23106/.
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The thesis concerns an examination of victim engagement with the police investigation of domestic abuse. Notwithstanding the huge efforts being made in tackling the problem by police forces across the UK, national inspections still find that the services provided to victims are “not good enough” (HMIC, 2014, p.6). Subsequently, the thesis argues that in order to build an approach around empowering victims of Intimate Partner Violence (IPV), there first needs to be further research into victim engagement with the police investigation (Birdsall et al., 2016; Hoyle & Sanders, 2000). Using the rationale, the research examined 540 cases of IPV to determine which factors were significantly associated with victim engagement. It controlled for suspect charging, cross validated the results with qualitative case file information and brought together the findings through an analysis of their co-occurrence. The process resulted in distinct themes and an overall model of victim engagement. The thesis concludes that the current risk assessment used routinely by the police to identify victim vulnerability does not take into account victim engagement. The thesis therefore proposes that the factors, themes and model of victim engagement developed throughout the thesis, as well as other means of assessing victim engagement, would need to precede the DASH risk assessment to provide a more effective evaluation of victim vulnerability. Doing so would allow the police to critically communicate and provide suitable support that is applicable to all victims of IPV. Crucially, the early indication of victim withdrawal would allow the police to identify some of the most vulnerable victims of abuse who would otherwise disengage from professional support and place themselves at greater risk of harm, injury and abuse.
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Parish-Fisher, Casie. "A comprehensive evaluation of a new direct amplification system (PowerPlex® 18D) in forensic DNA profiling." Thesis, University of Central Lancashire, 2016. http://clok.uclan.ac.uk/16542/.
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Short tandem repeat typing is the primary method of DNA identification used in the field of forensic science. Over the past several years the need to improve on this method has moved to the forefront of research. Due to the increasing number of criminal cases and the substantial backlogs most laboratories are facing, it is vital to evaluate methods which can produce quality DNA profiles in a fast and reliable manner. Direct amplification, also referred to as direct PCR, is one alternative method that has been proposed to address this issue. Direct amplification allows for the generating of DNA profiles without using the DNA isolation process. While direct PCR would reduce processing time and resources, it is unknown if this technique would be able to generate a robust full or partial profile from samples which could be collected from scenes of crime. Often crime scene personnel must use visualization techniques, either in powder or chemical form, in order to see and collect biological evidence for submission to a crime laboratory. In order to evaluate if direct PCR is a feasible solution a comparative study between a direct PCR kit and standard DNA profiling practices was undertaken using mock crime scene type samples. Samples of this nature include surfaces which have been exposed to fingerprint powders and whole blood which has been chemically enhanced for visualization. PowerPlex® 18D, a direct amplification system, and PowerPlex® 16HS, an extraction-based method, were used to produce the profiles. An assessment of the kits aimed to critically evaluate and compare how the direct amplification kit performs on samples which have been exposed to powder and chemical processing for visual enhancement. This will be done by reviewing two types of samples; epithelial cells which have been exposed the fingerprint powders (black, magnetic and white) and whole blood which has been exposed to chemicals (luecocrystal violet, amido black and ninhydrin). Samples subjected to direct amplification using PowerPlex® 18D generated DNA profiles with greater peak heights when compared to the extraction- based method. The peak balances for heterozygous loci were also higher and more full profiles were generated with direct amplification than with the extraction method. The amount of DNA retrieved from each substrate also varied even though the same amounts of starting material were deposited, proving that the type of substrate can affect the retrieval of DNA. Epithelial cell samples were most successful when processed with white powder. Magnetic powder samples also yielded a positive result when using direct amplification which was not expected as in previous data magnetic powder samples have not been successful. Whole blood samples which were processed with amido black produced profiles with lower overall peak heights when compared to the two other chemical processes. This could be attributed to the rinse step which is required when working with amido black. Ninhydrin was the most successful of the chemicals in generating full, good quality profiles.
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Williamson, Claire Louise. "The analysis of ballpoint inks with APCI-MS after fading with light, hydrogen peroxide and sodium hypochlorite bleach." Thesis, University of Central Lancashire, 2015. http://clok.uclan.ac.uk/16735/.
Full textAbstract:
The ability to discriminate between different inks and to determine the length of time an ink has been on a substrate can provide important scientific evidence, especially in cases involving document fraud. Many techniques have been used to analyse inks for ink dating including chromatography and spectroscopy, but the results are unreliable as a result of factors affecting the aging process such as light. This study utilises established techniques in Forensic Document Examination, including filtered light examination but also novel techniques for ink analysis; Atmospheric Pressure Chemical Ionisation (APCI) to analyse inks and dyes with the aim of discriminating between samples based on their degradation products. APCI-MS was used for the first time to study nineteen ballpoint pens from a range of manufacturers by investigating the chemical processes that occur and the products that are formed following the deposition of ink onto a substrate and in solution. Monitoring the degradation process as an ink ages and fades enables the identification of components present in the inks. Using molecular mass data, accurate ink component identifications could be made over a period of two years on samples subjected to a range of external influences. Light, hydrogen peroxide and sodium hypochlorite bleach were used to simulate natural and deliberate fading of inks and dye solutions. Benzophenone and phenol molecules were identified as degradation products but their presence differed for each of the different conditions tested such as no phenol products when bleach was used. This novel approach to ink analysis utilises existing equipment commonly used by document examiner to analyse inks that are old or faded in some way, in order to discriminate between the inks or determine method of alteration.
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Nag, Kaushik. "Manufacture and synthesis of a dark micro magnetic flake powder for forensic application." Thesis, University of Central Lancashire, 2010. http://clok.uclan.ac.uk/18853/.
Full textAbstract:
In the study a novel method for synthesis of a dark magnetic flake powder for detecting latent fingerprint has been developed. Even though, flake powders ,of aluminium, brass and highly reflective magnetic iron flake are already in use in crime scenes , it is highly desirable to develop a suitable darker variety of magnetic flake powder for print development on light background surfaces. In order to achieve rapid production of dark metal flakes, a new high energy prototype vibratory mill has been designed, manufactured and develo ed. The design concepts were developed following a comprehensive review of the various commercially available milling devices and undertaking some initial experimentation. The mechanical milling process which results in changing the particle morphology of starting atomised iron powder to flaky shaped powder was investigated in terms of different milling phases like micro forging, fracture and agglomeration. The effect of milling process parameters on the flake quality was investigated. It was shown that the amount of stearic acid content, ball packing fraction and weight loading were important parameters in determining the final flake qualities. The quality of latent fingerprint development with the dark flake powder was investigated. Some of the flake powders produced excellent ridge quality details with good adherence quality on a range of background surfaces. The present study has been able to establish the relationship between the visual characteristics ( dark) and adherence property of the flake fingerprint powder with respect to the particle dimensions and surface characteristics of the flakes. It was also found that finer flakes are darker in colour and the low weight percentage of stearic acid has produced the best adherence quality for the dark flake powder. Some unique relationship between the flake dimensions with the nature of the print deposit was also established as it was found that slightly coarser flakes are suitable for heavy print deposit whereas finer flakes are more sensitive to aged prints. Further, the role of process variables in influencing the milling process were established such that optimum conditions by vibration milling can be determined to obtain dark flakes of desired quality. While the weight loading significantly influenced the milling behaviour of the powder, the role of stearic acid as an additive was found to influence the surface quality of flakes, besides restricting particle welding. Increasing the pre determined theoretical ball size does not result in faster milling, but increasing the ball packing fraction from 50% to 70% has proved to be more effective. Some relation with the oxidising behaviour of the powder with vibration milling has also been established. Moreover, the study has demonstrated that high energy milling by a vibration mill can be utilised for consistent production of a novel dark magnetic flake powder.
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Patel, Rahima. "Glioma genetic profiling : the role of DNA repair and telomerase." Thesis, University of Central Lancashire, 2008. http://clok.uclan.ac.uk/21996/.
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Brain cancers inflict a disproportional burden of mortality upon sufferers. Due to the difficulties of diagnosis and treatment, survival is low with most patients succumbing to the disease within a year of diagnosis. This has been the imperative factor to underpin some of the molecular mechanisms regulating gliomas and to aid with the development of novel disease biomarkers specifically targeting immortalisation (telomerase). 1[mmortalisation not only requires telomerase but also an imbalance/inactivation of DNA repair functions such as 06 methylguanine-DNAmethyltransferase (MGMI) which is a major obstacle with regards to glioma chemotherapy. The primary focus of this study was to evaluate whether there was an association betweenh TERT and its many subunits: TEPI (human telomerase-associated protein 1), TNKS ( tankyrase), DCKI (dyskerin) and PARPI (poly (ADP-ribose) polymerase1 ) in human glioma compared to normal brain tissues and cell lines. Evidence suggests that hTERT was the only gene that was transcribed in all the glioma cell lines and tissues, while absent in the normal. Thus hTERT may represent a simple but reliable biological marker for distinguishing glioma tissues from normal. The hTERT gene is subjected to its own highly coordinated regulation in normal and cancer cells however, whether hTERT is regulated via methylation/demethylation in glioma is unknown. 5azadC treatment reduced hTERT expression, which resulted in the downregulation of telomerase protein and its activity. However, an inverse correlation between hTERT and MGMT expression was observed after treatment. Evidence shows that hTERT inactivation enhances sensitivity towards some chemotherapeutic agents, thus a combination of 5azadC with various chemotherapeutic agents proved to be more effective than chemotherapy administered on its own. Although 5azadC treatment activates MGMT and subsequently hyposensitises glioma cells toward alkylating agents, specifically TMZ (temozolomide), it may compensate by offering telomerase sensitised cells, thus providing an alternative avenue of therapy for the 50% of the glioma patients chosen for this study that have an unmethylated MGMT promoter. However, further clinical developments concerning this approach will be required. 5azadC is known for its toxicity and its effects are diverse, thus it is not favoured as a therapeutic agent. To address these issues three DNMTI (methylation gene) siRNAs were used, downregulating DNMTI directly and hTERT indirectly (possibly via the promoter methylation inhibition mechanism). Combining siRNA and chemotherapeutic agents (TMZ or taxol) enhanced the effects of both the drugs, thus offering an alternative method of treatment using lower concentrations of the drug and hence, reducing side effects, and improving the life expectancy of glioma patients. All glioma tissues used in this study, irrespective of grade or invasiveness, transcribed hTERT at approximately similar copy numbers however, only some of these tissues translated this to protein. This could be due to hTERT mRNA splicing or the involvement of other regulating factors. Several studies have reported that protein translation decreases with age, this would explain why only two of the older patient samples had detectable telomerase activity when they all expressed hTERT mRNA. However, additional studies using a larger cohort of glioma tissues would be needed to further understand the precise mechanism for the discrepancy in hTERT translation in the older glioma patients. Four novel sets of investigations were documented in this thesis resulting in publications: a) 77VKS expression was evaluated in glioma tissues for the first time, b) the effects of the demethylating agent 5-aza-2'-deoxycytidine (5azadC) on the expression of hTERT and MGMTin glioma cells was evaluated, C) combining DNMTI siRNA and chemotherapeutic agents (TMZ or taxol) enhancedth e efficacy of the chemotherapeutiacgents and, finally d) although, h TERT transcription was found in all glioma tissues used in this study irrespective of grade or invasiveness (at similar copy numbers), a discrepancy in translation was documented. Some of the finding from this study may well become the starting point for integrating translational research in to future clinical trial designs for cancer, specifically for glioma patients.
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Lynch-Aird, Jeanne Elizabeth. "Estimation of post-mortem interval using decomposition scales for hanging bodies." Thesis, University of Central Lancashire, 2016. http://clok.uclan.ac.uk/16582/.
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The extent of decomposition of a body can be used, in conjunction with accumulated degree days (ADD), to provide an estimate of the post-mortem interval (PMI). PMI estimations are important in aiding police to narrow down the possible identity of a body, and to include or exclude suspects, and also to establish the order of death for inheritance purposes when two or more potential beneficiaries die at around the same time. Previous studies have shown the decomposition pattern in hanging bodies to be different from that of a body on the ground, but the sample sizes used have been small. This study presents the results of a series of decomposition studies on hanging bodies in a variety of situations; clothed and unclothed, and fully or partially suspended. The study used domestic pigs (Sus scrofa) which enabled large enough sample sizes for statistical robustness. Pigs lying on the ground were used as controls. The pattern of decomposition in hanging pigs was found to differ sufficiently from that of pigs lying on the ground to require the creation of a novel decomposition scoring scale, which was used successfully to score both clothed and unclothed fully suspended bodies, as well as the upper, suspended, part of partially suspended bodies. The presence of loose, lightweight clothing, which did not impede insect access, was found to affect both the pattern and rate of decomposition in hanging pigs, with the clothed bodies decomposing faster than the unclothed bodies (p < 0.05, F2, 477 = 1238). The variations in the start weights of the pigs used for these studies was found to have a statistically significant effect on the rate of decomposition for both the hanging bodies and those on the ground (p < 0.05, F5, 714 = 1962) but the effect was so small as to make no practical difference across the range of start weights encountered. The effect of variation in start weight may be of greater concern, however, in scoring very heavy, obese, bodies and may be exacerbated by the increased fat-to-muscle ratios encountered in such bodies. Finally a set of ADD prediction tables were produced for the hanging and surface pigs. Further work is needed to establish to what extent these tables can be used for humans and, in light of the growing obesity problems in humans, to investigate the effect of weight and increased fat-to-muscle ratios on the pattern and rate of decomposition.
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Hayward, Adam Lewis. "Retention capabilities of different genera of wood for common ignitable liquids." Thesis, Boston University, 2013. https://hdl.handle.net/2144/21169.
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Thesis (M.S.F.S.) PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.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.
2031-01-01
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Hitewa, Alina Ndahafa. "Investigating the effect of NucleoSpin® Forensic Filters on DNA recovery from swabs." Master's thesis, Faculty of Health Sciences, 2021. http://hdl.handle.net/11427/33810.
Full textAbstract:
The burden of unresolved crime in South Africa highlights the need to improve methods of identifying perpetrators of crimes. One globally accepted method for human identification is forensic DNA profiling. Since trace evidence is often retrieved in small amounts, the optimal recovery of DNA from these samples is crucial. Methods for the recovery of touch DNA from swabs typically make use of a spin basket or filter, combined with a centrifugation step, to enhance the release of cells from the swab prior to DNA extraction. The NucleoSpin® Forensic Filter (Macherey-Nagel, Düren) is one such example, but it has not been thoroughly assessed on touch DNA samples. This study aimed to assess if the inclusion of the NucleoSpin® Forensic Filter significantly improved DNA recovery and DNA profiling success from cotton and flocked swabs used to collect touch DNA and buccal cells (control). Buccal cells and touch DNA samples were collected from 25 volunteers using each swab type (cotton and flocked) in duplicate. DNA was extracted from the samples using the NucleoSpin® DNA Forensic kit, one set with, and the other set without, NucleoSpin® Forensic Filters. DNA concentration was assessed using Qubit™ fluorometry and qPCR, and DNA profiling was done using the PowerPlex® ESX 16 system. The inclusion of the NucleoSpin® Forensic Filters significantly improved DNA concentration in buccal cells collected using flocked swabs (p = 0.035). However, no significant differences were noted for touch DNA samples, for either swab type. There was also no significant difference in DNA profiling success when NucleoSpin® Forensic Filters were used, regardless of swab and sample type. These results suggest that the NucleoSpin® Forensic Filters should not be included in the DNA extraction workflow, particularly for touch DNA samples. With only 16 % of touch DNA samples yielding full DNA profiles, there is the need to improve DNA recovery. Factors such as swab type and swab preservation buffers, should be investigated in future research.