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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 i 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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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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Sust, Luise. "Forensic science in combat of human trafficking". Thesis, Sust, Luise (2021) Forensic science in combat of human trafficking. Masters by Coursework thesis, Murdoch University, 2021. https://researchrepository.murdoch.edu.au/id/eprint/64890/.
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Although Forensic Science has become a crucial part of the investigation of many types of crime, the low number of scientific publications on the usage of Forensic Science to eliminate Human Trafficking or to speed up crime investigation, has given rise to the idea of conducting research on the role of Forensic Science in the investigation of Human Trafficking cases. The following literature review aims at judging the current importance of Forensic Science in solving and preventing Human Trafficking cases, at gathering ideas for the introduction of novel techniques and at identifying gaps of research within this field. For this purpose, a wider view, also addressing socio-economic topics, was applied.
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Swann, Lisa. "Chemical markers of decomposition for forensic science". Thesis, Curtin University, 2011. http://hdl.handle.net/20.500.11937/2103.
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This thesis describes investigations that were carried out to determine the chemical compounds produced during the decomposition of an animal model in the absence of a soil matrix. In order to do this, several analytical methods were developed for various classes of compounds. Stillborn piglets and whole adult pig carcasses were used to model the decomposition process.Samples for analysis were collected from field trials conducted at decomposition research facilities in Perth and Canada. Two separate locations were used to provide a ‘compare and contrast’ approach to the identities of compounds detected following the analysis of decomposition fluid.Gas chromatography-mass spectrometry was used for preliminary studies into short chain fatty acids that have the potential to show reproducible patterns over certain postmortem intervals. Samples were analysed following a simple aqueous dilution and filtration. Additional compounds were detected, including several long chain fatty acids, which were also investigated for their potential as indicators of postmortem interval. Samples collected from the two separate locations, Western Australia (Perth) and Southern Canada (Oshawa) were analysed. This enabled a comparison of components to be carried out under significantly different climatic conditions. To verify the identity of the compounds, the predicted fragmentation patterns and possible mechanisms based on the library search results were also determined and compared with the obtained mass spectral traces from the fluid samples.A simple capillary zone electrophoresis method with detection by ultraviolet absorbance spectrophotometry was developed for the determination of biogenic amines and amino acids. Resolution and total analysis time was improved after the method was subject to optimisation utilising a chemometric approach. A screening design followed by a central composite design was carried out, with peak resolution and total analysis time as response factors. The optimised method was applied to porcine decomposition samples with target analytes identified by migration time and spiking. Samples were analysed following a 1:4 dilution with methanol, followed by filtration.A method utilising liquid chromatography-electrospray-mass spectrometry was employed for the determination of 23 amino acids and amines in decomposition fluid. The effect of a complex sample matrix was investigated and found to have little to no effect on the analyte signal. Decomposition fluid samples required no sample preparation, other than filtration. To avoid overloading the column, optimum sample injection volume was 0.1 μL. Compounds were identified through precursor → product ion transition(s). The specificity of the LC-ESI-MS system enabled identification of all target compounds as being present in decomposition fluid. The identity of compounds that showed apparent trends in decomposition fluid was verified by predicting possible mechanisms for the precursor → product ion transition(s).Analysis of data from each developed analytical method was conducted to establish any distinct relationship between the levels of particular compounds produced with respect to time and temperature. Preliminary results indicate that fatty acids show an 8-day cyclic trend, whilst total amino acid abundance shows a 14-day cyclic trend. Other compounds such as indole and putrescine showed general increasing trends over the course of the field trials.Several analytical methods to analyse target compounds in decomposition fluid have been presented in this thesis, however, suggestions for future work are presented in the final chapter.
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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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Salem, Roberta Sue. "Developing a one-semester course in forensic chemical science for university undergraduates". Diss., Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1333.
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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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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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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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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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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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Houck, Max Michael. "An investigation into the foundational principles of forensic science". Thesis, Curtin University, 2010. http://hdl.handle.net/20.500.11937/1568.
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This thesis lays the groundwork for a philosophy of forensic science. Forensic science is a historical science, much like archaeology and geology, which operates by the analysis and understanding of the physical remnants of past criminal activity. Native and non-native principles guide forensic science’s operation, application, and interpretations. The production history of mass-produced goods is embedded in the finished product, called the supply chain. The supply chain solidifies much of the specificity and resolution of the evidentiary significance of that product. Forensic science has not had an over-arching view of this production history integrated into its methods or instruction. This thesis offers provenance as the dominant factor for much of the inherent significance of mass-produced goods that become evidence.
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Tse, Wai-hin Kenneth, i 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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Regupathi, Sonita. "A critical review of the applications of DART in forensic science and its relevance to forensic investigations". Thesis, Regupathi, Sonita (2018) A critical review of the applications of DART in forensic science and its relevance to forensic investigations. Masters by Coursework thesis, Murdoch University, 2018. https://researchrepository.murdoch.edu.au/id/eprint/43233/.
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Direct Analysis in Real Time (DART) was only introduced in 2005 and in this short period of time it has already proven to be an excellent analytical tool. Its ability to analyse samples in seconds without any sample preparation has allowed DART to perform exceedingly well in various applications. It even addresses the shortcomings of certain developed analytical techniques. In the field of forensic science, DART has the potential of becoming a key analytical tool as it is non-destructive and hence maintains the integrity of the sample. In this review, an overview of DART is given before the applications of DART in forensic science are explored to assess DART’s ability to complement and/or replace current analytical techniques.
Keywords: Direct Analysis in Real Time (DART), forensic science, analytical tool, forensic chemistry, analytical chemistry
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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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Tanui, Cecilia. "Development of a good practice frameworks in forensic science research". Thesis, Tanui, Cecilia (2019) Development of a good practice frameworks in forensic science research. Masters by Coursework thesis, Murdoch University, 2019. https://researchrepository.murdoch.edu.au/id/eprint/53899/.
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This paper focuses on the current best practices in the research methodology in the medical/ biomedical and biosciences disciplines and based on their recommendations and practices, developing best practice frameworks in forensic science research. Robust procedures have been identified and tested against several forensic papers that have been recently published to prove if they meet the selected criteria. The study will access the information acquired from previous forensic research papers and express the expectations of ideal forensic research, and this will lead to the development of a forensic framework that can be applied by researchers in different forensic disciplines. The idea that most of the forensic publications lack adequate scientific foundation is a critical issue that needs to be addressed to improve the validity and reliability of conclusions made in forensic science research. The 2009 National Academy of Sciences report Strengthening Forensic Science in the United States: A Path Forward pointing out the unscientific state of various forensic subfields has a clear indication of a knowledge gap regarding the reliability of the methods used in the research process(61). The President’s Council of Advisors on Science and Technology(62) report in 2016, has reviewed the matter and made recommendations for further progress in the challenges facing forensic science. The conclusion addresses the importance of developing forensic research culture that follows the selected procedures aimed at improving forensic science research.
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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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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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Steenberg, Lindsay. "Sexy/dead : gender and forensic science in the contemporary crime thriller". Thesis, University of East Anglia, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501746.
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Since the early 1990s, there has been a dramatic shift in the crime genre. The hunches and action-driven narratives of previous investigations have made way for experts whose knowledge of criminalistics and profiling has become the genre's primary procedure and spectacle. Similarly, female investigators are joining hyper-masculine and hardboiled detectives in scrutinising the genre's typically female murder victims. That specialised expert knowledge and female investigators should become a preoccupation of the genre at the same cultural moment demands further scrutiny. This thesis argues that they are interconnected - representing anxieties over women's changing professional roles, and a perception in postmodern and postfeminist media culture that women, in particular, are increasingly at risk of violent attack.
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James, Sarah Jane. "Changing faces, facing changes : forensic science in search of new horizons". Thesis, University of Leicester, 2012. http://hdl.handle.net/2381/10173.
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The focus of this thesis is a study of change in a public sector environment and the effect it has on that environment. It is a combination of an empirical study of the author’s former employer, specifically the Police Scientific Support Department, and a critical analysis of the technique used to carry out the study and its application, Soft Systems Analysis. The thesis is multi‐layered through the additional use of a diary, which gives a more personal view of what the author experienced during the project, along with a third more clinical and critical review of the project and its outcomes through Actor‐Network Theory. This allows the author to portray a number of different perspectives on the same reality. The author’s position within the force as project manager, allowed comprehensive access in which to carry out detailed action research through at‐home ethnography, unstructured interviews and documentary data collection. A police force’s forensic strategy and the way it conducts its business in order to provide a comprehensive service, offer value for money and work within a limited budget, is a complex process which is affected by many factors. Some of these include political issues over government finance, organisational issues surrounding staff levels and their deployment, as well as technical issues over available techniques, their success rates and how to make the most efficient and effective use of them. The case study covers a period during which the construction of a new Scientific Support single site is being carried out. Many departments are being moved to the new site, away from their city centre base, to provide a more comprehensive and extended service.
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Roux, Brian. "Application of Digital Forensic Science to Electronic Discovery in Civil Litigation". ScholarWorks@UNO, 2012. http://scholarworks.uno.edu/td/1554.
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Following changes to the Federal Rules of Civil Procedure in 2006 dealing with the role of Electronically Stored Information, digital forensics is becoming necessary to the discovery process in civil litigation. The development of case law interpreting the rule changes since their enactment defines how digital forensics can be applied to the discovery process, the scope of discovery, and the duties imposed on parties. Herein, pertinent cases are examined to determine what trends exist and how they effect the field. These observations buttress case studies involving discovery failures in large corporate contexts along with insights on the technical reasons those discovery failures occurred and continue to occur.
The state of the art in the legal industry for handling Electronically Stored Information is slow, inefficient, and extremely expensive. These failings exacerbate discovery failures by making the discovery process more burdensome than necessary. In addressing this problem, weaknesses of existing approaches are identified, and new tools are presented which cure these defects. By drawing on open source libraries, components, and other support the presented tools exceed the performance of existing solutions by between one and two orders of magnitude. The transparent standards embodied in the open source movement allow for clearer defensibility of discovery practice sufficiency whereas existing approaches entail difficult to verify closed source solutions.
Legacy industry practices in numbering documents based on Bates numbers inhibit efficient parallel and distributed processing of electronic data into paginated forms. The failures inherent in legacy numbering systems is identified, and a new system is provided which eliminates these inhibiters while simultaneously better modeling the nature of electronic data which does not lend itself to pagination; such non-paginated data includes databases and other file types which are machine readable, but not human readable in format.
In toto, this dissertation provides a broad treatment of digital forensics applied to electronic discovery, an analysis of current failures in the industry, and a suite of tools which address the weaknesses, problems, and failures identified.
32
Jackson, Graham. "The development of Case Assessment and Interpretation (CAI) in forensic science". Thesis, Abertay University, 2011. https://rke.abertay.ac.uk/en/studentTheses/f257a491-8061-4bfd-ba08-d1477092ebcb.
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Expert opinion has been, and still is, of undoubted assistance in the investigation of crime and the administration of criminal justice. It has also been the cause of a number of celebrated miscarriages of justice. Technological advances and greater investment in forensic science resources in the latter half of the 20 century meant that forensic science could be applied to many more cases than ever before. It also meant that forensic scientists had to meet new challenges in the way they formed and expressed opinions about their findings. The creation of a commercial market for forensic science in the 1990s in England and Wales put additional pressures on suppliers to provide value-for-money for their customers. In an attempt to satisfy the potentially conflicting demands of providing robust, reliable opinion and of giving value-for-money, a novel process called Case Assessment and Interpretation (CAI), based on the underlying logic of Bayes Theorem and the use of likelihood ratios, was proposed in 1998 as a model of good practice in forensic science. Over the course of the next 12 years, the model process was applied to most main-stream forensic science disciplines and, as a result, the ideas were refined and fresh insights on the nature of expertise were gained. This thesis describes the background to the initial development of the CAI model, sets out subsequent improvements, demonstrates how the model may have helped avoid misleading opinion being given and considers the current status of CAI. The conclusion of the thesis is that assessment of likelihood ratios, within the framework of the Case Assessment and Interpretation model, does provide a philosophical, yet practical, means of delivering robust, reliable opinion and value-for-money.
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Hendry, Stephen John. "Application of metallic profiling of teeth for environmental and forensic science". Thesis, University of the West of Scotland, 2016. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.738485.
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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.
36
Rayaud, Sophie. "Stable isotope analyses of keratin for human provenance : implications for forensic science". Thesis, University of Reading, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590134.
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This research explores the application of carbon, nitrogen, oxygen and hydrogen isotopic analysis of modem human hair and nail tissues for forensic purposes. Carbon and nitrogen isotopic signatures are transferred from the environment to plants and to human tissues through trophic levels, therefore reflecting the diet. Oxygen and hydrogen isotopes are closely linked to the geographical location of the individuals through precipitation. drinking water and food products. The use of carbon, nitrogen, oxygen and hydrogen isotopic analysis of "hair and nail tissues can therefore be applied to diet-reconstruction and geo-localisation of individuals, which has been widely used on older human remains. Hair and nail are ideal tissues for obtaining a precise temporal archive of diet and location due to their known and relatively constant growth rates. The high keratin content of these tissues (between 65 and 95% by weight) enables analysis of small sample sizes, without prior chemical purification, which makes them ideal matrices in forensic investigations where sample size is often a limiting factor. The easy and non• invasive sampling of hair and nail tissues enables the transfer of this application to living humans, which has been the focus of forensic scientists for several years. In this study, hair and nail samples were collected from 134 volunteers from Reading (UK) with known diet and geographical movements. A total of 43 hair samples and 74 fingernail samples were also collected from volunteers living in Kenya, whose recent travel record was known. A total of 17 hair samples and 10 fingernail samples were also collected from a group of27 individuals claiming to be of Somalian origin but who could have been Kenyan, as part of the British Human Provenance Project. These samples were compared to the two reference groups from Reading and Kenyan volunteers in order to assess their likely area of origin, and to determine their diet. The results obtained in this study confirm the potential of carbon and nitrogen isotopic analysis of modem human hair and nail tissues in discriminating between the different levels of protein intake of omnivore, ovo-lacto-vegetarian (OL V) and vegan diets. Through the largest dataset analysed so far (mostly from Europe and Kenya), this research confidently reports the effect of location on δ13C, δ 2H and δ 180 values of human tissues. Hair and nail δ13C values show significant differences between locations with diverse proportion of C3/C4 food product intake (USA and Kenya versus Europe), while locations such as Kenya, Australia and Turkey show significantly enriched 02H and δ180 values than locations at higher latitudes such as Spain, France, Germany and the United-Kingdom. The level of location discrimination is however increased by a simultaneous combined approach of δJ3C and δ2H analysis, which enables the determination of the likely area of origin of samples from uncertain location to a greater extent than the isotope ratio pairs (δ13C- δ15N, δ2H- δ18O). This study also presents a unique dataset of a series of hair and nail samples from the same individual (n=74 for δ13C and δ 15N and n=60 for δ 2H and δ 18O), showing strong correlations between these two tissues.
37
Yang, Chi-ting, i 楊志婷. "Pharmacokinetics of alcohol using breath measures and some statisticalaspects in forensic science". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46506159.
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Schober, Cassandra C. (Cassandra Carolyn). "The Evolution, Applications, and Statistical Interpretations of DNA Typing in Forensic Science". Thesis, University of North Texas, 1997. https://digital.library.unt.edu/ark:/67531/metadc332776/.
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This thesis examines the evolution, applications, and statistical interpretations of DNA typing as a tool in the field of forensic science as well as in our criminal justice system. The most controversial aspect of DNA typing involves the determination of how likely it is that two people share the same DNA profile. This involves the use of population genetics and databases of allelic frequencies as well as some assumptions about population structuring.
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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
40
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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Burkey, Chris Rush, Tusty ten Bensel i Jeffery T. Walker. "Forensic Investigation of Sex Crimes and Sexual Offenders". Digital Commons @ East Tennessee State University, 2013. https://www.amzn.com/0323228046.
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The investigation of sex crimes is a specific function for many law enforcement agencies, requiring an understanding of how to investigate, process crime scenes, interact with victims and offenders, and prepare for court. Drawing on new methods of investigation and the effects of such crimes on victims, Forensic Investigation of Sex Crimes and Sexual Offenders provides in-depth coverage in these areas, offering a valuable supplement for criminal justice courses and an accessible guide for law enforcement.https://dc.etsu.edu/etsu_books/1134/thumbnail.jpg
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Patterson, Farrah M. "The implications of virtual environments in digital forensic investigations". Master's thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4819.
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This research paper discusses the role of virtual environments in digital forensic investigations. With virtual environments becoming more prevalent as an analysis tool in digital forensic investigations, it's becoming more important for digital forensic investigators to understand the limitation and strengths of virtual machines. The study aims to expose limitations within commercial closed source virtual machines and open source virtual machines. The study provides a brief overview of history digital forensic investigations and virtual environments, and concludes with an experiment with four common open and closed source virtual machines; the effects of the virtual machines on the host machine as well as the performance of the virtual machine itself. My findings discovered that while the open source tools provided more control and freedom to the operator, the closed source tools were more stable and consistent in their operation. The significance of these findings can be further researched by applying them in the context of exemplifying reliability of forensic techniques when presented as analysis tool used in litigation.ID: 030646240; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.S.)--University of Central Florida, 2011.; Includes bibliographical references (p. 46).
M.S.
Masters
Computer Science
Engineering and Computer Science
Digital Forensics; Science/Computing Track
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Saks, Michael J., Thomas Albright, Thomas L. Bohan, Barbara E. Bierer, C. Michael Bowers, Mary A. Bush, Peter J. Bush i in. "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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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.
47
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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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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Gallo, Jenny M. "Elemental analysis of cotton fiber evidence for use in the field of forensic science". FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/3440.
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The purpose of this research is to introduce a method for the forensic elemental analysis of cotton fibers for the purpose of increasing the discrimination between otherwise similar cotton evidence using microwave digestion Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Laser Ablation- Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS). A quadrupole ICP-MS and UV laser ablation (266nm) instruments were used for the analysis. A cotton standard reference material (IAEA V-9) was used to validate the developed methods producing good accuracy with typically 10 % bias and good precision (typically 5% RSD) for the element list: 25Mg, 27Al, 55Mn, 57Fe, 88Sr and 137Ba. It was found that the LA-ICP-MS method resulted in improved precision over the solution ICP-MS method. Twenty four (24) raw cotton samples and five white cotton T-Shirts were analyzed with the developed methods. It was also found that all the raw cotton samples from different sources were distinguishable from each other, as were all the cotton T-shirts resulting in zero type I errors and zero type II errors for the pairwise comparisons.
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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.