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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.
1

The hydrogeological context of cemetery operations and planning in Australia.

Dent, Boyd B. January 2002 (has links)
The purpose of this research has been to evaluate the potential contamination impact of cemeteries on groundwater. A comprehensive study of the groundwaters in the unsaturated and saturated zones of nine Australian cemeteries has been made, with most sampling between October 1996 and August 1998. Periodic sampling from 83 wells or ponds yielded 305 complete samples which were tested for at least 38 inorganic and 5 bacterial analytes. Other, partially complete samples were used for metals and bacterial analyses. The soils of all sites were tested for a range of analytes that might reflect or affect the presence of human decomposition products. The within-cemetery sampling has allowed inorganic chemical characterisation of cemetery groundwaters to an amount of detail not previously attained. In the past 100 years there have been fewer than 12 sampling-based studies published on any of these matters. The forms of nitrogen feature most prominently, but three groupings of analytes are recognised as major contributors, including Na, Mg, Sr, Cl, SO4 and forms of P; these outcomes are similar in each hydrogeological zone. This study is unique in that it has a broad focus on the environmental impacts in respect of bacterial presence and transmission, heavy metals and nutrients, and has put these into the context of cemetery management and operational practices. Cemetery functions are best understood conceptually as a special kind of landfill but they are strongly influenced by the temporal and spatial variability of cemetery practices. Human decomposition mechanisms and products are considered in detail. This information was used to model the impacts for a large municipal cemetery over a twenty year time-frame. The previously unquantified relationship of cemetery proximity to drinking water wells has been determined and guiding principles for cemetery location and operation have been prepared including separation distances from watertables and specification of buffer zones in different hydrogeological settings. The related issue of the disposition of cremated remains is also considered and guidelines developed for scattering of these within buffer zones. The amounts of decomposition products leaving cemeteries are very small, and well sited and managed cemeteries have a low impact on the environment. Cemeteries should not be regarded as a detrimental landuse and the in-soil interment of human remains and re-use of graves are sustainable activities. However, almost all cemeteries have some potential for pollution. The most serious situation is the escape of pathogenic bacteria or viruses into the environment at large. The answer to the question as to ‘whether any one cemetery pollutes?’ depends on the location and operation of the site in adherence to the affecting parameters. The question can only be resolved by a comprehensive geoscientific investigation with a focus on the hydrogeological setting. Such assessment needs to consider the effects if the practices and/or usage patterns within the cemetery change, or if there are unaccounted changes in impacting natural phenomena like floods.
2

Vegetation colonization of experimental grave sites in central Texas /

Callahan, Casey A. January 1900 (has links)
Thesis (M.A.)--Texas State University--San Marcos, 2009. / Vita. Appendix: leaves [32]-47. Reproduction permission applies to print copy: Blanket permission granted per author to reproduce. Includes bibliographical references (leaves [48]-51). Also available on microfilm.
3

Soil-cadaver interactions in a burial environment

Stokes, Kathryn Lisa January 2009 (has links)
Forensic taphonomy is concerned with investigation of graves and grave sites. The primary aim of forensic taphonomy is development of accurate estimations of postmortem interval (PMI) and/or postburial interval (PBI). Soil has previously been largely ignored, therefore this thesis is designed to investigate changes in decomposition as imparted by the soil. Furthermore the impact of cadaver interment on the surrounding soil may offer prospects for identification of clandestine graves. A series of laboratory controlled decomposition experiments using cadavers (Mus musculus) and cadaver analogues (skeletal muscle tissue (SMT); Sus scrofa, Homo sapiens, Ovis aries and Bos Taurus) were designed to investigate decomposition in burial environments. Sequential destructive harvests were carried out to monitor temporal changes during decomposition. Analyses conducted included; mass loss, microbial activity (CO2 respiration) and soil chemistry (pH, EC and extractable NH4 +, NO3 -, PO4 3- and K+). Several experimental variables were tested; frozen-thawed versus refrigerated SMT, different mammalian sources of SMT, different soil type and contribution of soil versus enteric microbial communities. Mass loss measurements for SMT experiments demonstrated a sigmoidal pattern of mass loss, however, larger cadavers (Mus musculus, 5 weeks) did not. The inhumation of SMT (frozen, unfrozen, different mammalian sources) or cadavers leads to an increase in microbial activity (CO2 respiration) within 24 hours of burial. A peak of microbial activity is attained within a week, followed by a decrease and eventual plateau. The rapid influx in microbial activity is matched by corresponding increases in pH and NH4 + concentration. pH and NH4 + are strongly correlated in soils with acidic basal pH, by comparison highly alkaline soil demonstrated no relationship. NH4 + concentration also appeared to be related directly to NO3 - concentration and cadaver or SMT mass. A decrease in NH4 + corresponds with an increase in NO3 -, however, nitrification was unpredictable. Rapid nitrification was observed in sand systems when SMT was interred, but was not noted when cadavers were interred. By comparison both sandy clay loam and loamy sand soils demonstrated rapid nitrification after inhumation of a cadaver. When cadaver or cadaver analogue mass was larger, so were NH4 + and NO3 - concentrations in systems that experienced nitrification.
4

Human Decomposition Ecology at the University of Tennessee Anthropology Research Facility

Damann, Franklin Edward 01 December 2010 (has links)
The University of Tennessee Anthropology Research Facility (ARF) is well known for its unique history as a site of human decomposition research in a natural environment. It has been integral to our understanding of the processes of human decomposition. Over the last 30 years 1,089 bodies have decomposed at this 1.28 acre facility, producing a density of 850 corpses per acre of land. This project evaluated the abiotic and biotic characteristics of the soil exposed to various levels of human decomposition in order to determine the effect on the physicochemical properties and the indigenous bacterial communities. Specifically, 75 soil samples were taken to determine abiotic properties. A biological matrix was generated for the 40 samples inside the facility based on sequencing of the 16S rDNA gene. The identified taxonomy was evaluated for differences among decomposition bins and taxa. Results of the abiotic soil properties demonstrated few differences among the predefined bins of decomposition density. Significant differences were observed between samples inside the facility to the negative control, and to those samples taken below actively decomposing corpses. When taken together, the abiotic data demonstrated a temporal shift away from control, with the greatest deviation at 18 to 24 months. After which time, the samples became more similar to control samples. Similarly, the biotic data remained concordant with the abiotic data, but demonstrated significant differences between the areas of high decomposition to those with no history of decomposition. The high decomposition bins were marked by high levels of chemoorganotrophic and sulfate-reducing bacteria, and a reduction in Acidobacteria, indicating a change in the community of underlying bacteria in response to carcass enrichment and ammonification of the soil. Thirty years of decomposition research at the ARF has forced a shift in the underlying bacterial community in response to the enrichment of the soil with increased nitrogen and carbon-containing compounds. The baseline data presented in this work provides a control dataset for further exploration regarding the biogeochemical relationships among microbial organisms, soil characteristics, and cadaver decomposition. Within this relationship exists the potential for developing new models relating to postmortem interval estimation and clandestine grave location.
5

THE EFFECT OF ALTITUDE ON DECOMPOSITION: TOWARD AN UNDERSTANDING OF THE POSTMORTEM INTERVAL IN THE ROCKY MOUNTAIN REGION OF COLORADO.

Baigent, Christiane Irene 01 May 2024 (has links) (PDF)
The estimation of postmortem interval (PMI) is a critical component of medicolegal death investigation. An accurate PMI estimate has the potential to influence the allocation of investigative resources, establish the probative value of associated biological and material evidence, shape the analytical framework applied to skeletal analysis, and inform cause and manner of death. Forensic anthropologists are often tasked with PMI estimation throughout all stages of decomposition and typically rely on categorical phases of soft tissue and skeletal change purported to correspond to broad estimates of elapsed time. In an attempt to improve precision, Megyesi et al. (2005) developed the Total Body Score model (TBS). This quantitative method relies on qualitative assessment of value-assigned categories of tissue change within three anatomical regions to estimate accumulated degree days (ADD), and subsequently, PMI. However, the TBS model has failed to prove reliable in a diversity of region-specific validation studies, emphasizing the need for environment-specific research in taphonomy study. Toward that end, the rate, pattern, and trajectory of decomposition was assessed among a cohort of 12 human donors in the high-altitude Rocky Mountain region of Colorado. This research was performed at Colorado Mesa University’s Forensic Investigation Research Station high-altitude satellite facility, FIRS-TB40. The site lies at an elevation of 3000 meters/9840 feet above mean sea level (AMSL), in the Dfc (snow, fully humid, cool summer) climate region. With both significantly higher elevation and an unrepresented climate classification, FIRS-TB40 introduces a novel environment for the controlled study of human decomposition. This quadripartite study sought to (1) test the qualitative and quantitative aspects of the TBS model in a high-altitude environment to assess suitability of application in the estimation of local PMI; (2) test seven atmospheric variables to assess the utility of integrating atmospheric data beyond ADD into PMI estimation; (3) establish the rate and pattern of human decomposition, isolate and describe phasic patterns of soft tissue change throughout the trajectory of decomposition, and (4) develop a region specific bioecological profile with an emphasis on the integration of human behavior.Results: (1) Neither the qualitative or quantitative aspects of the TBS model tested well at high-altitude and are therefore not recommended for application within the study environment. The qualitative changes presented in the TBS model were not observed among the high-altitude cohort. While Megyesi et al. report that time and temperature - as measured by ADD - accounts for 84% of the variance observed throughout decomposition, ADD accounted for only 42% of the variance observed in decomposition within the high-altitude cohort. (2) Seven atmospheric variables were assessed using locally estimated scatterplot smoothing (LOESS) and multivariate regression. Two of these variables - accumulated solar radiation days (r2 = 0.67) and accumulated windspeed days (r2 = 0.65) – explained more variance in decomposition than ADD (r2 = 64). (3) Five categories of phasic, macroscopic soft tissue change, the suite of which is inferred unique to high-altitude, were identified. These include adipocere formation, trajectory of soft tissue color change, fluid bloat, tissue island formation, and skin sloughing. Patterns of slope roll and slope wash were also described to inform the local taphonomic profile. (4) A forensic bioecological profile was developed using empirically derived patterns of scavenger behavior, census and land use data, extant ethnographic data, and forensic case study. Analysis demonstrated that the data sources were cyclically informative and sufficient to develop an early phase foundational model that will benefit from future interdisciplinary research.Summarily, the high-altitude region of Colorado is culturally and environmentally distinct. The observed disparity in rate and pattern of human decomposition between the high-altitude cohort and the TBS model, and the inadequacy of ADD alone to predict PMI are demonstrative of the need for environment-specific model building in human taphonomy research.
6

Adaptation of the microbial decomposer community to the burial of skeletal muscle tissue in contrasting soils

Luitingh, Taryn Leigh January 2008 (has links)
Microorganisms are known to be agents involved in the decomposition of organic matter. However, little is known about the participation of the microbial communities during the decomposition of mammalian skeletal muscle tissue. This study investigates the capacity of the soil microbial community to adapt to the decomposition of skeletal muscle tissue in differing soils. This has implications for the study of mass graves and sites of repeated burial. A controlled laboratory experiment was designed to assess the adaptability of microbial communities present in three distinct soil types (sand, loamy sand and sandy clay loam) found near Perth, Western Australia. This experiment was split into two main stages. The initial decomposition stage involved the addition of porcine skeletal muscle tissue (SMT) (Sus scrofa) to each of the three soil types which were then left to decompose for a period of time. Controls were run in parallel, which had no porcine SMT present. The second decomposition stage involved a second addition of SMT to the soils obtained from the initial decomposition stage. Therefore, for each soil, SMT was either decomposed in the soil that had been pre-exposed to SMT or not. The rate of decomposition, microbial activity (CO2 respiration) and microbial biomass (substrate-induced respiration) were monitored during the second decomposition stage. The functional diversity of the microbial populations in the soil were assessed using Community-Level Physiological Profiling (CLPP). Across the three soil types, the re-introduction of SMT to the soil has led to its enhanced decomposition (measured by tissue mass loss and microbial activity) by the microbial communities. This microbial adaptation may have been facilitated by a functional change in the soil microbial communities.
7

Laboratory Detection Limits of Potential Human Decomposition Products Under a Variety of Soil Conditions

Travaly, Sarah Elizabeth 07 November 2016 (has links)
No description available.
8

Influence du climat provincial sur l’identification de restes humains en décomposition exposés en milieu naturel dans le sud du Québec : optimisation des méthodes de restauration et prélèvement des empreintes digitales

Séguin, Karelle 03 1900 (has links)
Les empreintes papillaires sont principalement utilisées à des fins d'identification par les forces policières, chez les individus vivants et décédés. Dans les contextes forensiques, l'étendue de la conservation/décomposition de restes peut avoir un impact sur la capacité de restaurer et prélever les empreintes papillaires, et par conséquent, sur les méthodes utilisées. L’application de ces méthodes sur le terrain (p. ex. en cas de catastrophes de masse ou fosses communes) ne peut pas compter sur les mêmes installations/ressources de laboratoire, et nécessite des adaptations pratiques. Ce travail de recherche représente la première application et comparaison dans un cadre expérimental des méthodes de restauration et prélèvement des empreintes papillaires à partir de restes humains en décomposition dans des conditions contrôlées au Québec. Deux essais ont été menés sur quatre donneurs au site de Recherche en Sciences Thanatologiques Expérimentales et Sociales (REST[ES]); un à l’été 2021 et un à l’automne/hiver 2021-2022. Au total, cinq méthodes existantes de restauration et trois méthodes de prélèvement, développées sous d'autres climats, ont été expérimentées. Les résultats ont montré que les méthodes pouvaient être adaptées pour une application sur le terrain, de manière simple, rapide et économique. Les restaurations et prélèvements après l'hiver ont été réalisées de façon moins invasive et destructrice qu'en été, où des variables incontrôlables ont limité leur application. Basé sur ces résultats, deux outils ont été développés pour soutenir la prise de décision des praticiens du Québec (Canada) lors du choix des méthodes à prioriser dans les cas réels forensiques. / Fingerprints are primarily used for identification purposes by law enforcement, for both living and deceased individuals. In forensic contexts, the extent of preservation or decomposition of remains can impact the ability to restore and collect fingerprints, and subsequently the methods used. Additionally, implementation of these methods in the field in cases of mass disasters or mass graves cannot rely on laboratory facilities and resources, and therefore require practical adaptations. This research work represents the first application and comparison in an experimental setting of fingerprints restoration and collection methods from decomposing remains under controlled conditions in Quebec. Two trials were conducted on four donors at the site for Research in Experimental and Social Thanatology (REST[ES]); one in summer 2021 and one in fall/winter 2021-2022. In total, five existing restoration methods and three collection methods, developed in other climates, were tested. Results showed that fingerprint restoration and collection methods could be adapted for practical applications in real forensic contexts, in a simple, rapid, and cost-effective way. Fingerprints restorations and collections after winter were achieved in less invasive and destructive manners than in summer, where uncontrollable variables limited their application. Based on these results, two tools have been developed to support the decision-making of forensic practitioners in Quebec (Canada) when choosing which methods to prioritize in real forensic cases.
9

Utilisations du microbiome en sciences judiciaires

Leblanc, Audrey-Anne 08 1900 (has links)
La microbiologie judiciaire consiste à utiliser des microorganismes comme éléments de preuves dans une enquête judiciaire. Elle est appliquée dans plusieurs buts, dont l’identification de fluides biologiques et la compréhension des mécanismes de décomposition des cadavres entre autres. L’objectif de ce mémoire est de tester l’application de nouvelles méthodes de prédictions utilisant la microbiologie judiciaire et d’évaluer leur potentiel pour le domaine. Dans un premier temps, au chapitre 2, nous avons étudié une nouvelle méthode pour identifier les fluides vaginaux par le microbiome. Alors que plusieurs méthodes existent pour identifier des sources pures de fluides vaginaux, nous avons testé un modèle sur des mélanges de fluides pour voir s’il était possible de reconnaître la présence de sources vaginales dans ceux-ci. Nos résultats montrent que le modèle utilisé avec le seuil choisi a une spécificité de 100% en ce qui a trait à l’identification de fluides vaginaux dans des mélanges et une sensibilité de 70%. Ainsi, nos résultats démontrent qu’il serait possible d’utiliser éventuellement cette méthode en sciences judiciaires. Dans un deuxième temps, au chapitre 3, nous avons exploré le changement du microbiome épinécrotique sur une période de sept mois comprenant un hiver complet. Nous avons pu identifier les taxons spécifiques qui ont une différence d’abondance significative entre les saisons et ainsi développer un modèle de prédiction qui peut déterminer si un corps a passé l’hiver ou non. Notre modèle n’a jamais prédit qu’un corps n’avait pas passé l’hiver quand en réalité c’était le cas, mais a parfois surestimé les résultats. / Microbial forensics uses microorganisms as physical evidence in different investigations. It is used in multiple ways, such as the identification of body fluids or the understanding of the different mechanisms of body decomposition. The objectives of this research are to apply novel prediction methods using microbial forensics and assess their potential for forensic science. First, in chapter 2, we studied a novel method to identify vaginal fluids using the microbiome. Similar methods already exist to identify pure sources of body fluids, but we tested a model that could find vaginal fluids in mixture samples. Our results show that the model used with the chosen threshold has a specificity of 100% and a sensitivity of 70% for the identification of vaginal fluids in mixtures. Therefore, our results show that it would be possible to use this method in the future in forensic science. Second, in chapter 3, we explored the change of the epinecrotic microbiome over a 7-months period including a full winter. We could identify specific taxa that were differentially abundant before and after winter and developed a prediction model that would calculate if a body went through winter or not. The model never predicted that a body did not go through winter when it did, but it sometimes overestimated the results predicting it went through winter when it did not.

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