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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Three dimensional (3D) forensic facial reconstruction in an Egyptian population using computed tomography scanned skulls and average facial templates : a study examining subjective and objective assessment methods of 3D forensic facial reconstructions

Abdou, Dalia Ahmed Selim Ali January 2018 (has links)
Forensic facial reconstruction can assist identification by reconstructing a face of the unknown person with the aim of its recognition by his/her family or friends. In the facial reconstruction approach adopted in this study, a 3D average face template was digitally warped onto a 3D scanned skull image. This study was carried out entirely on an Egyptian population, and was the first of its kind. Aims: This study aimed to demonstrate that 3D facial reconstructions using the novel methodology described could show significant resemblance to the faces corresponding to the persons in question when they were alive. Moreover, using techniques previously validated for facial reconstruction, the aim was to compare them to the method developed, and to assess approaches used to determine the accuracy of 3D facial reconstructions. Methods: Initially, a pilot study was conducted using a database of laser scanned skulls and faces. The faces were reconstructed using an average facial template generated by merging a number of faces of similar population, sex, and age. The applicability, as well as the main components of the facial reconstruction method, the single and average facial templates, and the facial soft tissue thickness measurements, were investigated. Furthermore, in the main study, the faces of computed tomography (CT) scanned heads of an Egyptian population were reconstructed using average facial templates. The accuracy of the reconstructed faces was assessed subjectively by face pool, and face resemblance tests, and objectively by measuring the surface distances between the real and reconstructed faces. In addition, a number of novel subjective and objective assessment methods were developed. These included assessment of individual facial regions using subjective resemblance scores, and objective surface distance comparisons. A new objective method, craniofacial anthropometry, was developed by taking and comparing direct measurements from the skull, and comparing the measurements from the real and reconstructed faces. The studied cases were ranked according to all subjective, and objective, tests, and statistically correlated. Results and Conclusions: The average facial templates showed a higher identification rate than the single face templates. The approach of facial reconstruction used in this thesis showed a comparable accuracy to many other facial reconstruction methods, yet was superior in terms of its applicability, transferability, and ease of use. In the face pool tests, the younger assessors were able to correctly identify the reconstructed faces better than older assessors. Furthermore, the identification rate by the forensic anthropology experts was higher than the non-experts. The former group showed the highest agreement between the observers in giving the resemblance scores. Although there was a significant rank correlation between the subjective and objective assessment tests, the subjective tests are influenced by the assessors' subjective characteristics (e.g., age, professional experience), thus making objective assessment more reliable. However, in situations where subjective tests are used, it is better to use the face resemblance tests and consult forensic anthropologists. Also, Craniofacial Anthropometry, particularly the craniofacial angles, can successfully indicate the accuracy of the facial reconstructions. Importantly, this study shows that certain facial regions, particularly the cheek and the jaw, are more reliable than other areas in the subjective and objective assessment of the facial reconstruction.
12

Sensitive forensic DNA analysis : application of pyrosequencing and real-time PCR quantification /

Andréasson, Hanna, January 2005 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2005. / Härtill 6 uppsatser.
13

Sexual assault forensic medical examinations and certified nurse-midwives differences by provider type : a thesis submitted in partial fulfillment ... for the degree of Master of Science, Parent-Child Nursing ... /

Rosa, Anne K. January 2001 (has links)
Thesis (M.S.)--University of Michigan, 2001. / Includes bibliographical references.
14

Post-mortem toxicogenetics: determining the suitable of blood samples collected for routine toxicological analyses for use in subsequent genetic analyses

Vuko, Loyiso Abongile Marvin 14 February 2019 (has links)
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.
15

A study of drug use, pathology and post-mortem tissue distribution in the West of Scotland

Fitrasanti, Berlian Isnia January 2018 (has links)
Drug abuse has always been a world problem. Recently people abuse both controlled and prescribed drugs. Opioids, cocaine, cannabis and amphetamines are the most widely abused drugs. The picture of the drug abuse problem in Scotland can be understood by an extensive study of drug prevalence and characteristics of drug use in the region. In drug-related deaths, post-mortem analysis, which includes autopsy and collecting samples for histological and toxicological analysis, is necessary to be carried out to investigate whether any drug has contributed to the cause of death. The samples which are commonly collected for toxicological analysis are blood and urine. However, when those fluids are not available, body tissues may be taken as alternative samples, such as liver and skeletal muscle. In this case, it is necessary to understand how drugs move and diffuse to these tissues after death. This phenomenon, which is known as post-mortem redistribution, may cause difficulties in the interpretation of post-mortem drug concentrations. Several studies have tried to investigate post- mortem redistribution including how drugs diffuse in the body after death. However, post-mortem redistribution is still not completely understood. This study proceeded by interrogating post-mortem data within the period of 2011-2016 held by Forensic Medicine and Science (FMS), University of Glasgow to review trends of drug-related death in the West of Scotland in which amphetamine-type stimulants (ATS), cocaine and opioids were detected. Opioids were most commonly detected (81.9%) in drug-related deaths in the West of Scotland, followed by cocaine (21.6%) and ATS (9.4%). The interrogation of post- mortem data within the period of 2007-2016 was also carried out to understand certain pathological conditions which are caused by drug abuse. From the results, it is clear that in the West of Scotland people tend to abuse multiple drugs. This trend may apply in the other part of the country and around the world. It is also clear that, even though methadone was prescribed to assist users to stop from drug addiction, especially heroin, many methadone users still abuse other drugs, as methadone was found in most of the cases in addition to other drugs. For this reason, it is important to investigate the results of drug addiction therapy and educate potential users. Subsequently, methods were adapted for analysing liver and muscle samples from the FMS in-house methods for analysing ATS and basic drugs in autopsy blood and validated according to the standard practices for method validation in forensic toxicology (SWGTOX, May 2013). All ATS drugs (amphetamine, methamphetamine, MDA, PMA, PMMA, MDMA and MDEA) and basic drugs (amitriptyline, citalopram, methadone, mirtazapine, sertraline and tramadol) gave acceptable bias, precision, linearity, recovery and stability for analysing liver and muscle samples. An experimental model for drug diffusion in tissues was studied to simulate and understand drug diffusion in humans. The diffusion rate that was used in this model is in accordance with the volume of distribution of each drug. This model is easy and simple to be carried out in any small laboratory. Blood, liver and muscle samples were analysed from 10 cases collected during the period from August 2016 to April 2017 after the next of kin signed the informed consent forms. Four basic drugs (amitriptyline, methadone, mirtazapine and sertraline) were found in 9 cases and analysed to investigate the ratios between blood, muscle, right liver and left liver. The ratios of drug concentrations of muscle:blood, left liver:right liver were found to be lower than 2. As a result, drug concentrations in muscle can be reliable for toxicological interpretation when blood is not available. The ratio of drug concentration in liver and blood has been suggested as a marker of post-mortem redistribution(1) and this study has shown that the ratio of drug concentration in liver and muscle can also be diagnostic in cases where blood is not available.
16

Fatal penetrating injuries of the chest

Scholtz, Hendrik Johannes January 1996 (has links)
In the Republic of South Africa, an autopsy is required in all cases of unnatural death, or in cases where the cause of death is unknown in terms of the Inquest Act of 1959. These are performed at the Salt River Medicolegal Laboratory by Forensic Pathologists and Registrars of the Department of Forensic Medicine and Toxicology of the University of Cape Town. The Salt River Medicolegal Laboratory serves the greater Cape Town area with a population of approximately 2,5 million, including the magisterial districts of Cape Town, Wynberg, Mitchell's Plain and Simonstown. Cape Town has one of the world's highest homicide rates and in 1986 the incidence was 56, 91 100000 population per annum. In contrast, Singapore has a homicide rate of only 2, 5/100 000, while the United States has an overall homicide rate of 7,7/ 100 000 population. In order to document the true impact of penetrating chest injuries, and to place mortality data in perspective, a retrospective descriptive study of all cases with fatal penetrating chest injuries admitted to the Salt River Medicolegal Laboratory in Cape Town during 1990 was undertaken. In 1990, a total of 5 758 cases was admitted to the Salt River Medicolegal Laboratory of which 1834 cases (39%) were the result of homicide. Of the homicide cases, 408 (22%) were the result of firearm injuries. A total of 2044 (35, 5%) cases admitted was deemed to have died of natural causes. This study identified a total of 841 cases of fatal penetrating injuries of the chest admitted during 1990, which constituted 22,6% of all non-natural cases admitted.
17

An anthropological study of war crimes against children in Kosovo and Bosnia-Herzegovina in the 1990s

Roberts, Julie Ann January 2011 (has links)
Between 1991 and 1999 war broke out across Former Yugoslavia. Thousands of people are believed to have been killed and many more were internally displaced or forcibly expelled from their countries. In 1993 the United Nations established the International Criminal Tribunal for Former Yugoslavia (ICTY) to investigate war crimes allegedly committed in the region. Its work is still ongoing. This research comprises an anthropological study of the children in Kosovo and Bosnia-Herzegovina who were killed as a direct result of war crimes perpetrated during the conflicts of the 1990s. It is based on primary forensic data collected by investigators and scientists on behalf of ICTY between the dates of 1996 and 2000. From this data, a single integrated database was created which allowed the numbers of child deaths, causes of death, demographic profiles of the deceased, and post-mortem treatment of their remains to be analysed. As well as examining these factors within each country a significant aspect of the research included comparative analysis between the crimes committed against children in Kosovo and those in Bosnia-Herzegovina. Broad comparisons were also made between adult and child data in both countries. The findings from the research were analysed within their wider socio-political context and an assessment was made of how closely the forensic evidence supported accounts from other literary sources. In its current form, the research can be used as a historical and scientific resource by those wishing to study both the events surrounding the wars in Kosovo and Bosnia-Herzegovina, and the scientific methods used by experts in the field to investigate the crimes. The methodology employed during the research, including the creation of the database, is described in detail and is directly transferrable to other studies of a similar nature. Solutions employed to address the considerable problems encountered during the construction of the database can be applied to other similarly large and unmanageable datasets. The database itself can be expanded to include the forensic evidence collected in Bosnia-Herzegovina and Kosovo since 2001, when ICTY handed over responsibility for the exhumations to local government agencies. It can also be used to examine other aspects of the wars, and adapted to analyse data from other countries. Ultimately it is hoped that this research will be of use in formulating pro-active strategies which might assist in protecting children involved in future conflicts.
18

Applications of LC-MS/MS in forensic toxicology for the analysis of drugs and their metabolites

Al-Asmari, Ahmed Ibrahim January 2009 (has links)
This thesis studied opioids and alcohol in forensic toxicology by LC-MS/MS, which avoids time-consuming procedures involving hydrolysis, extraction and derivatisation. Initially, a method was validated for quantification of opioids and unhydrolysed polar metabolites in autopsy specimens and was used to develop procedures for interpretation of forensic toxicology results. The LC-MS/MS method developed has been validated for the simultaneous determination of 24 opioids in human whole blood, including, for the first time in human whole blood, naloxone-3-glucuronide. Although a large number of drugs of interest were included in the method, acceptance criteria for linearity, precision, and recovery for all analytes were achieved. The method was found useful for differentiating between users of heroin and other opioids, such as codeine and morphine, and for determining the survival time in deaths attributed to heroin use. Subsequently, the efficiencies of hydrolytic and non-hydrolytic methods for opioid analysis were compared for buprenorphine (BUP) analysis. The aims were to develop and validate a method for the direct determination (DM) of buprenorphine (BUP), norbuprenorphine (NBUB), buprenorphine-3-glucuronide (B3G) and norbuprenorphine-3-glucuronide (NBUP3G). This method was compared with an in house enzymatic hydrolysis method (HM) for the determination of total buprenorphine (TBUP) and norbuprenorphine (TNBUP), using real positive BUP urine case samples. A comparison between the drug and metabolite concentrations obtained by direct and hydrolysis methods was reported for the first time in this work. LC-MS analysis was also applied to paediatric plasma specimens obtained from a clinical pharmacokinetic study of intravenous and intranasal administration of diamorphine. This work was aimed at obtaining pharmacokinetic data for diamorphine and its metabolites in children following intravenous (IVDIM) and intranasal (INDIM) administration in a blind study. It was intended that the concentrations of active metabolites would be used to evaluate whether or not IN-DIM can deliver rapid and efficient analgesia in children comparable to that obtained with IV-DIM. The pharmacokinetics of DIM and its metabolites following INDIM and IVDIM administration in children have been compared for the first time in this study, which confirmed that INDIM can achieve therapeutic plasma concentrations of active metabolites, although these were lower than those obtained with IVDIM and occur at later times after administration. In Scotland, the number of prescriptions for oxycodone has risen by 430% since prescribing began in 2002. Blood samples from fatalities in the West of Scotland involving oxycodone were analysed using an LC-ESI-MS/MS method developed for the determination of oxycodone and its metabolites in post-mortem specimens. To the author’s knowledge, this is the first report of blood and urine concentrations of noroxycodone and oxymorphone in acute oxycodone overdoses. Also, it is the first LC-MS/MS application to be reported with oxycodone related fatalities cases in forensic toxicology as most of previous reports used GC or HPLC applications. Moreover, this work reported for the first time vitreous humour levels of noroxycodone following oxycodone intoxication. Ten oxycodone-related deaths were identified in the short period of this study in the Strathclyde region of Scotland alone, highlighting the importance of including this drug in routine laboratory screening and confirmation procedures. Polar alcohol metabolites ethyl glucuronide and ethyl sulfate are biomarkers of ante-mortem alcohol consumption and are used to test for post-mortem artefactual formation of alcohol. An LC-MS method for these metabolites using a novel hydrophilic interaction liquid chromatography column was validated and applied to routine forensic casework. Ninety urine case samples were divided into three groups depending on the ethanol concentration found in blood and analysed by the developed method: group A with post-mortem blood ethanol higher than 200 mg/100 mL; group B with ethanol concentration in the range 80 to 200 mg/100 mL and group C with ethanol concentration less than 80 mg/100 mL. It was concluded that the risk of false positive ethanol results increased in the low ethanol concentration group as several cases tested negative for both biomarkers. ETG was detected at low concentrations in some cases for which ETS tested negative, suggesting that either ETG may have a longer half-life in urine or else ETS is unstable. The data was compared with previous studies and confirmed that both ethanol biomarkers should be determined in heavily putrefied cases and when the ethanol level in post-mortem blood is low, suggesting the production of ethanol after death. To the authors’ knowledge, this is the first report of the determination of ETS using an LC-ESI-ion trap-MS/MS method, and of a HILIC-ESI-ion trap-MS/MS method for the simultaneous determination of ETG and ETS in post-mortem urine samples.
19

Diagnostic use of hair analysis for the detection of misuse of amfetamines and cannabinoids

Bin-Eisa, Fahad Nasser January 2007 (has links)
The purpose of this study was to develop a single method to analyse drugs in hair and to apply this to case samples received from The Security Forces Hospital, Saudi Arabia. First of all, mass fragments and retention times for amfetamines and cannabinoids were identified by GC-MS using derivatization agents, PFPA/ethyl acetate (2:1 v/v) and PFPA / PFPOH (1:0.75 v/v) for amphetamines and cannabinoids, respectively. The results showed good peak shape, good chromatographic resolution and good sensitivity for amfetamine (AF), methamphetamine (MA), 3,4-Methylenedioxyamfetamine (MDA), 3,4-Methylenedioxymethamfetamine (MDMA), 3,4-Methylenedioxyethylamfetamine (MDEA), Δ9-tetrahydrocannabinol (Δ9-THC) and 11-nor-9-carbody- Δ9-tetrahydrocannabinol (Δ9-THC-COOH) compounds. The comparison of the efficiency of four different pre-treatment methods (enzymatic, alkaline, acid and methanol) to extract AF, MA, MDA, MDMA, MDEA, Δ9THC and Δ9-THC-COOH from hair samples obtained from known amfetamines and cannabinoid abusers was investigated. The preliminary results demonstrated difficulty with the cannabinoids recovery and the lower concentration of standards were not detected using any of the pre-treatment methods. As a result of the poor cannabinoids recovery, only the amfetamines were investigated. For the comparison study, only one hair sample positive for amphetamine was available so the pre-treatment comparison study was based on the recovery of AF using the four pre-treatment methods. The positive hair sample was separated into portions and pre-treatment methods, alkaline (1M NaOH), β-Glucuronidase (helix pomatia), methanol (MeOH) and acid (0.1M HCI) were used on these and compared. The best recovery for amphetamine was obtained using the β-glucuronidase pre-treatment method and this extract was also found to be cleaner than the alkaline and methanol pre-treatments. Β-glucuronidase pre-treatment was selected as the method of choice for the extraction of amphetamine content in hair. The method was validated to include linearity, recovery, intra- and inter-day precision, limit of quantitation (LOQ) and limit of detection (LOD) for all five amphetamine compounds. The method was shown to be reliable and robust for these substances. The stability of AF in hair was investigated to assess the validity of analysing hair samples for the presence of AF in victims of drowning. Ten amphetamine positive hair samples were submerged in fresh and sea water for different periods of time. The drug concentrations in the samples were monitored over a period of 8 weeks. Hair samples were analysed using the validated method. The results showed a significant decrease of amphetamine in hair with the time submerged in sea water. Fresh water had a much less significant effect over the study period. The validated method was successfully applied to 16 case samples obtained for living volunteers with a known history of fenethylline (AF precursor) abuse and 6 post-mortem case samples where amfetamines had been detected in the post-mortem blood.
20

Volatile compounds in the blood of fire fatalities

Cheng, Kun Nang January 1984 (has links)
An attempt was made to evaluate the importance of smoke and toxic gas inhalation in fires by comparing the volatile constituents in blood taken from fire fatalities with those of normal healthy and post-mortem controls. At the initial stage of the project, particular attention was given to the measurement of carbonyl compounds which represent a series of toxic and strongly irritant thermal degradation products from many polymeric materials. Three analytical methods, namely, i) gas chromatographic analysis of carbonyls after conversion to their corresponding 2,4-dinitrophenyl hydrazone derivatives, ii) direct static headspace gas chromatography, and iii) dynamic headspace gas chromatography, were compared for their applicability to the measurement of carbonyls in blood. Problems associated with binding of carbonyls to blood proteins were experienced in the first two methods which precluded their use for this application. The latter method was found to be most suitable in this respect since the bound carbonyls were released during the purging process. The method was also the most sensitive and when used in conjunction with a mass spectrometer, a detection limit in the nanogram per millilitre range was obtained. Volatiles in blood were extracted by purging the samples (1 ml) with 0.6 litre of helium and collecting the components on a small Tenax-GC column. The volatiles were then thermally desorbed and analysed by gas chromatography-mass spectrometry using a 100 m x 0.5 mm i.d. Carbowax 20M SCOT column. The sorption technique was found to extract a wide range of volatile components from blood enabling a comparison of volatile profiles to be made. Thus initially organic nitriles as well as the carbonyl compounds were quantified. Volatile components were identified by comparison of their retention indices and mass spectra with those of authentic standards. Where the latter were not available, tentative identifications were made 9n the basis of their mass spectral data only. Quantification of carbonyls and nitriles was achieved by comparing their response ratios to those from an external standard under identical conditions. During the period from August 1981 to May 1982, thirty-one blood volatile profiles were studied. These included four normal healthy controls and six post-mortem controls. In general, more complex profiles were found in fire fatalities than those of the controls. Over 140 chemical species have been identified in these! profiles and these include series of carbonyls, nitriles, alcohols, esters, aliphatic and aromatic hydrocarbons, halogenated hydrocarbons, heterocyclic compounds and sulphur-containing compounds. A detailed examination of the profiles has indicated that those compounds which might be of significance fell into two main catagories: those which were strong sensory and respiratory irritants, and those which were depressants of the central nervous system. Quantitative measurements of carbonyls in blood have shown that the mean levels of 2-butanone, butandione, 2-pentanone, cyclopentanone, cyclohexanone and hexanal were higher in fire fatalities than those in the controls. Of particular concern were the very high levels of acetonitrile and the presence of acrolein Ca highly toxic and strong sensory irritant) in the blood of some of the fire fatalities. Although the toxicological significance of these gaseous toxicants in causing fire fatalities has yet to be established, the results have clearly demonstrated that most of the fire deaths included in this exposed to a wide range of toxicants. these compounds may have played a vital incapacitation during the fire.

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