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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.
21

"Návrat svalů a tuku zpět na kosti": 3D analýza vlivu tělesné kompozice a hmotnosti na kostní architekturu / "Putting flesh and fat back onto the bones": A 3D analysis of the influence of body composition and mass on bone architecture

Lacoste Jeanson, Alizé January 2018 (has links)
Univerzita Karlova Přírodovědecká fakulta Antropologie a Genetika člověka Alizé Lacoste Jeanson, M.Sc. "NÁVRAT SVALŮ A TUKU ZPĚT NA KOSTI": 3D ANALÝZA VLIVU TĚLESNÉ KOMPOZICE A HMOTNOSTI NA KOSTNÍ ARCHITEKTURU "PUTTING FLESH AND FAT BACK ONTO THE BONES": A 3D ANALYSIS OF THE INFLUENCE OF BODY COMPOSITION AND MASS ON BONE ARCHITECTURE Disertačnn prace Doctoral thesis Školitel Supervisor: Prof. RNDr. Jaroslav Brůžek, CSc, PhD, HDR Praha, 2018 Prague, 2018 Charles University Faculty of Science Department of Anthropology and Human Genetics Abstract The understanding of biomechanics is essential to various studies in bioanthropology. Bone is a living tissue that constantly remodels in order to functionally adapt to biomechanical constrains. Long bones diaphyses in particular have been subjected to various analyses notably because the application of beam engineering principles has rendered possible the evaluation of their resistance to various directional constrains based on their shape. Body mass estimation methods lie on this principle. Body mass is partially used since the nineties as a proxy to control the influence of body size on bone's architecture prior to interpreting variations between populations. More recently, they have been used to estimate physical status (i.e. emaciation, norm, obesity)....
22

Simulations of mechanical adaptation and their relationship to stress bearing in skeletal tissue

Hirschberg, Jens January 2005 (has links)
[Truncated abstract] In this work a computer simulation program, similar to a finite element program, is used to study the relationship between skeletal tissue structure and function. Though other factors affect the shape of bone (e.g., genetics, hormones, blood supply), the skeleton adapts its shape mainly in response to the mechanical environment to which it is exposed throughout life. The specific relationship between the mechanical environment and the mechanical adaptation response of the skeleton is reviewed. Theories of mechanical adaptation are applied to the sites of tendon attachment to bone (entheses), the adaptation of generalised trabecular bone (i.e., Wolff’s Law of trabecular architecture), sesamoid bones that are often found where a tendon wraps around a bony pulley, and the internal trabecular structure of a whole bony sesamoid such as the patella. The relative importance of compression rather than tension in bone adaptation theories is still not fully understood. Some mechanical adaptation theories suggest that an overwhelming tensile stress at a skeletal location does not stimulate bone deposition, but would instead lead to bone resorption. The skeletal locations studied in this work were chosen because they have been proposed to be in tension. Computer simulations involving models are an ideal method to analyse the mechanical environment of a skeletal location. They are able to determine the mechanical stresses at, and the stress patterns around, complex biological situations. This study uses a two dimensional computer simulation program, Fast Lagrangian Analysis of Continua (Flac), to analyse the stress at the skeletal locations, and to test theories of mechanical adaptation over time by simulating physiological adaptation. The initial purpose of this study is to examine the stress in the skeletal tissue in generalised trabeculae, anatomical sites where a tendon wraps around a bony pulley, in the trabecular networks that fill the patella, and at tendon attachments. A secondary purpose, that follows directly from the first, is to relate the results of these initial stress analyses to existing and hypothetical skeletal tissue remodelling theories, to suggest how the complex skeletal structures might be generated solely in response to their mechanical environment. The term “remodelling” is used throughout this work to refer to mechanical adaptation of bone, usually at a surface of bone, rather than the internal regeneration of osteons (Haversion systems)
23

Abnormal bone mineralization in adolescent idiopathic scoliosis and its relation with plasma and tissue expression of osteopontin. / CUHK electronic theses & dissertations collection

January 2012 (has links)
青少年特發性脊柱側凸(Adolescent idiopathic scoliosis , AIS)是一種複雜的脊柱三維畸形,常見於10-16 歲處於生長發育高峰期的青少年女性。儘管AIS 發生率較高並且臨床影響較大,但是到目前為止其病因未明。在眾多關於AIS 病因學的假設和理論研究中,普遍認為低骨密度是AIS 的一個重要影響因素。然而近年來對於AIS 患者低骨密度研究不足,其潛在的機制尚不明確。我們之前初步的組織學研究發現,AIS 患者的松質骨中成骨細胞功能下降,此研究為AIS中存在骨礦化異常提供了初步依據。 / 骨橋蛋白是骨組織中一種重要的非膠原細胞外基質蛋白,其在骨礦化過程中起著重要作用。近期的研究報導AIS 患者血漿中骨橋蛋白水準高於年齡匹配的正常對照。因此本研究假設AIS 患者血漿及骨組織中骨橋蛋白高於正常對照,并可能影響了骨基質的礦化,從而導致低骨密度。 / 本系列研究的第一部分旨在通過外周定量電腦斷層掃描(pQCT)明確AIS患者中皮質骨密度及松質骨密度是否均低於正常對照。pQCT 可以準確地三維評估皮質骨密度,松質骨密度及其他骨品質的相關參數。採用雙能X 線骨密度儀(DXA)測量受試者的非優勢側近端股骨面積骨密度(包括股骨頸,Ward’s 三角及大轉子)。而採用pQCT 測量受試者非優勢側橈骨遠端容積骨密度,包括皮質骨密度及松質骨密度。結果顯示AIS 患者面積骨密度,皮質骨密度及松質骨密度在不同年齡段和月經時間分組中均低於正常對照。並且AIS 與正常對照皮質骨密度的差異隨著年齡增長越來越大,而松質骨密度差異則隨著年齡增長越來越小。 / 第二部分通過顯微CT 及組織形態測定研究AIS 及正常骨組織的骨礦化及骨微結構。採用顯微CT 檢測骨組織的三維結構參數,包括材料骨密度及骨微結構。未脫鈣骨組織的切片通過Goldner’s 染色進行組織形態學測量。結果顯示AIS患者的骨體積分數,骨小梁數目,骨小梁厚度及結構模型指數與正常對照之間均無顯著差異,而材料骨密度顯著低於正常對照。組織形態學分析結果顯示AIS中低礦化骨顯著多於正常對照。 / 第三部分旨在研究AIS 及正常對照血漿中骨橋蛋白水準及其與骨密度的關係。採用酶聯吸附免疫法測量AIS 患者及年齡匹配的正常對照血漿中的骨橋蛋白水準。血漿骨橋蛋白水準與骨密度的關係採用多元回歸分析。研究結果顯示AIS 患者及正常對照血漿骨橋蛋白水平均與年齡及月經時間呈負相關。AIS 患者的血漿骨橋蛋白水準顯著高於正常對照,並且與松質骨密度呈顯著負相關。 / 本研究第四部分旨在探討骨組織中的骨橋蛋白表達與骨形態學及骨礦化指標在AIS 及正常對照中的關係。骨組織中骨橋蛋白的表達採用半定量免疫組織化學法評估。研究結果顯示在AIS 中血漿骨橋蛋白水準與骨組織中骨橋蛋白的表達呈正相關。且AIS 骨組織中骨橋蛋白的表達也顯著高於正常對照。進一步的研究發現骨組織中骨橋蛋白的表達與材料骨密度呈負相關,而與低礦化骨量呈正相關。 / 本研究明確了AIS 中骨礦化水準低於正常對照,進一步證明AIS 患者中的皮質骨及松質骨密度下降可能與骨礦化的調控異常有關。本研究發現的骨橋蛋白與低骨密度及低骨礦化水準的關係,可以推測AIS 患者中異常升高的骨橋蛋白水準可能在骨礦獲取的調解中起重要作用。本系列研究提供證據支援AIS 患者中骨橋蛋白的異常表達可能影響了骨基質的礦化,從而導致低骨密度。本研究為AIS 中低骨密度可能的機制提供了全新的見解,並可能進一步解釋AIS 的發病機理及其發生,發展。 / Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional deformity of the spine occurring most commonly in girls between ages 10-16 during the pubertal growth spurt. Despite its high prevalence and clinical impact, etiology of AIS remains largely unknown. Among the number of proposed hypothesis and observations on the etiopathogenesis of AIS, low bone mineral density (BMD) is one of the most reported factor (Cheng et al. 1999; Hung et al. 2005; Cheung et al. 2006; Hui et al. 2011). However, the underlying mechanism of low BMD in AIS has not been sufficiently studied scientifically and its link to the etiopathogenesis is still not clear. From a previous pilot study, our group has reported the histological features of reduced osteoblastic activity in bone biopsy specimens obtained from AIS subjects intraoperatively, thus providing the early evidence of abnormal bone mineral acquisition and mineralization (Cheng et al. 2001). / Osteopontin (OPN) has been recognized as one the major non-collagen extracellular matrix proteins in bone and plays an important role in bone mineralization. Recent report suggested that AIS patients have higher OPN level than normal controls (Moreau et al. 2009). It was hypothesized that the low BMD in AIS is associated with abnormal bone matrix mineralization which may be related to abnormal expression of OPN in the plasma and at tissue level. / In this series of studies, the first part aimed to investigate the differential cortical and trabecular bone mineral density of AIS Vs normal controls. The non-dominant proximal femur areal BMD (aBMD) (femoral neck, Ward’s triangle and greater trochanter) of the subjects were measured with dual-energy x-ray absorptiometry (DXA). The volumetric bone mineral density (vBMD) in non-dominant distal radius was measured with peripheral quantitative computed tomography (pQCT) that allows accurate three dimensional assessment of the cortical and trabecular bone mineral density and other parameters of bone quality. AIS was found to have lower aBMDs, trabecular BMD (TBMD) and cortical BMD (CBMD) in different age groups and year since menarche (YSM) groups. Furthermore, the percentage difference of CBMD between AIS and controls was increased with age while a decreasing trend was observed in the TBMD. / The second part of the study investigated the bone mineralization and bone micro-architecture with micro-computed tomography (micro-CT) and histomorphometry study of bone biopsies obtained from AIS and normal controls. Three-dimensional structural parameters including material bone mineral density (mBMD) and bone architecture were evaluated by micro-CT. Bone histomorphometry was assessed by undecalcified sectioning with Goldner’s trichrome staining. mBMD of trabecular bone in AIS was found to be significantly lower than the normal control while no difference could be demonstrated in BV/TV, Tb.N, Tb.Th and SMI measurement between the two groups. It was also shown that the percentage of low-mineralized bone in AIS was significantly higher than that in normal controls. / The third part aimed to study the plasma OPN level and its association with the BMD in AIS Vs normal controls. Plasma OPN level in AIS and age-matched controls was measured by ELISA. With multivariate regression analysis, the plasma OPN level was found to be negatively correlated with Age and YSM in both AIS and normal controls. In addition, the plasma OPN level in AIS was significantly higher and correlated with the low trabecular BMD. / The fourth part of the study investigated the OPN expression in bone tissues level and its association with histomorphometric bone mineralization and bone micro-architectural parameters in AIS Vs normal controls. OPN expression in bone biopsy was semi-quantified by immunohistochemistry. It was found that the bone tissue OPN level was significantly higher in AIS and also positively correlated with plasma OPN level. In addition, in this pilot study, we found the trend that OPN expression in trabecular bone was negatively associated with mBMD, and positively with the percentage of low-mineralized bone. / The present study showed that AIS had lower bone mineralization than normal controls. The low cortical and trabecular BMD found in AIS is likely to be resulting from abnormal regulation of bone mineralization. The association of OPN with abnormal BMD and bone mineralization further suggested that abnormal OPN level might play an important role in affecting the bone mineral acquisition in AIS. All of these findings strongly supported the hypothesis that the low BMD in AIS is associated with abnormal bone matrix mineralization which could be related to abnormal expression of OPN. This study provided important additional insight into the possible mechanism of lower bone mineral density that might be linked to theetiopathogenesis, development and progression of the spinal deformity in AIS. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Sun, Guangquan. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 143-160). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract and appendix A also in Chinese. / THE CHINESE UNIVERSITY OF HONG KONG --- p.I / ACKNOWLEDGEMENTS --- p.II / ABSTRACT --- p.IV / ABBREVIATION --- p.XI / TABLE OF CONTENTS --- p.XIII / LIST OF TABLES --- p.XVII / LIST OF FIGURES --- p.XIX / LIST OF PUBLICATIONS --- p.XXI / Chapter CHAPTER 1 --- STUDY BACKGROUND --- p.1 / Chapter 1.1 --- GENERAL OVERVIEW OF ADOLESCENT IDIOPATHIC SCOLIOSIS (AIS) --- p.2 / Chapter 1.1.1 --- NATURAL HISTORY --- p.4 / Chapter 1.1.2 --- CURRENT TREATMENTS --- p.6 / Chapter 1.1.2.1 --- Observation --- p.7 / Chapter 1.1.2.2 --- Bracing --- p.7 / Chapter 1.1.2.3 --- Surgical treatments --- p.9 / Chapter 1.1.3 --- CURRENT HYPOTHESIS ON THE ETIOLOGY OF AIS --- p.11 / Chapter 1.1.3.1 --- Genetic factors --- p.12 / Chapter 1.1.3.2 --- Neuromuscular impairment --- p.14 / Chapter 1.1.3.3 --- Abnormalities in skeletal development --- p.16 / Chapter 1.1.3.4 --- Low bone mineral density in AIS --- p.16 / Chapter 1.2 --- BONE MINERALIZATION --- p.18 / Chapter 1.2.1 --- Overview of bone mineralization --- p.18 / Chapter 1.2.2 --- Bone modeling --- p.18 / Chapter 1.2.3 --- Bone remodeling --- p.19 / Chapter 1.2.4 --- Factors affecting bone mineralization --- p.21 / Chapter 1.3 --- OSTEOPONTIN --- p.23 / Chapter 1.3.1 --- Structure of osteopontin --- p.23 / Chapter 1.3.2 --- Osteopontin - cellular and tissue distribution --- p.24 / Chapter 1.3.3 --- Osteopontin functions --- p.25 / Chapter 1.3.4 --- Osteopontin functions in bone --- p.25 / Chapter 1.3.5 --- Osteopontin and bone mineral density in human --- p.29 / Chapter CHAPTER 2 --- STUDY HYPOTHESIS AND PLAN --- p.31 / Chapter 2.1 --- INTRODUCTION --- p.32 / Chapter 2.2 --- HYPOTHESIS --- p.33 / Chapter 2.3 --- OBJECTIVES --- p.34 / Chapter 2.4 --- STUDY PLAN --- p.34 / Chapter CHAPTER 3 --- LOW BONE MINERAL DENSITY IN ADOLESCENT IDIOPATHIC SCOLIOSIS - AREAL VS VOLUMETRIC, CORTICAL VS TRABECULAR BONE MINERAL DENSITY --- p.36 / Chapter 3.1 --- INTRODUCTION --- p.37 / Chapter 3.2 --- SUBJECTS AND METHODS --- p.39 / Chapter 3.2.1 --- Subjects --- p.39 / Chapter 3.2.2 --- BMD Measurement --- p.40 / Chapter 3.2.3 --- Statistical Analysis --- p.41 / Chapter 3.3 --- RESULTS --- p.42 / Chapter 3.3.1 --- aBMD of AIS and normal controls by age groups --- p.42 / Chapter 3.3.2 --- TBMD and CBMD in AIS and normal controls by age groups --- p.42 / Chapter 3.3.3 --- aBMD in AIS and normal controls by year since menarche --- p.43 / Chapter 3.3.4 --- TBMD and CBMD in AIS and normal controls by year since menarche --- p.43 / Chapter 3.3.5 --- Correlation between CBMD & TBMD and chronological age or year since menarche --- p.44 / Chapter 3.3.6 --- Comparisons adjusted for chronological age or year since menarche --- p.44 / Chapter 3.4 --- DISCUSSION --- p.45 / Chapter 3.5 --- TABLES AND FIGURES --- p.50 / Chapter CHAPTER 4 --- ABNORMAL BONE MATRIX MINERALIZATION AND BONE MICROARCHITECTURE IN ADOLESCENT IDIOPATHIC SCOLIOSIS - A HISTOMORPHOMETRIC AND MICRO-CT STUDY --- p.60 / Chapter 4.1 --- INTRODUCTION --- p.61 / Chapter 4.2 --- SUBJECTS AND METHODS --- p.62 / Chapter 4.2.1 --- Subjects --- p.62 / Chapter 4.2.2 --- Micro-computed tomography --- p.63 / Chapter 4.2.3 --- Bone histomorphometry --- p.64 / Chapter 4.2.4 --- Statistical analysis --- p.68 / Chapter 4.3 --- RESULTS --- p.68 / Chapter 4.3.1 --- Results of micro-CT analysis --- p.68 / Chapter 4.3.2 --- Results of histomorphometric analysis --- p.69 / Chapter 4.3.3 --- Relationship of mBMD and percentage of low-mineralized bone --- p.69 / Chapter 4.4 --- DISCUSSION --- p.70 / Chapter 4.5 --- TABLES AND FIGURES --- p.74 / Chapter CHAPTER 5 --- PLASMA OSTEOPONTIN LEVEL AND ITS ASSOCIATION WITH BONE MINERAL DENSITY IN ADOLESCENT IDIOPATHIC SCOLIOSIS --- p.82 / Chapter 5.1 --- INTRODUCTION --- p.83 / Chapter 5.2 --- SUBJECTS AND METHODS --- p.84 / Chapter 5.2.1 --- Subjects --- p.84 / Chapter 5.2.2 --- Anthropometric assessment --- p.84 / Chapter 5.2.3 --- Plasma osteopontin measurement --- p.85 / Chapter 5.2.4 --- BMD Measurement --- p.86 / Chapter 5.2.5 --- Statistical Analysis --- p.86 / Chapter 5.3 --- RESULTS --- p.86 / Chapter 5.3.1 --- Comparison of anthropometric parameters between AIS and controls --- p.86 / Chapter 5.3.2 --- Correlation between OPN plasma level with age or YSM in AIS and controls --- p.87 / Chapter 5.3.3 --- Comparison of OPN plasma level between AIS and controls --- p.87 / Chapter 5.3.4 --- Correlation between OPN plasma level and curve severity in AIS --- p.87 / Chapter 5.3.5 --- Relationship between OPN plasma level and vBMD --- p.88 / Chapter 5.4 --- DISCUSSION --- p.88 / Chapter 5.5 --- TABLES AND FIGURES --- p.94 / Chapter CHAPTER 6 --- OSTEOPONTIN EXPRESSION IN BONE TISSUE AND ITS ASSOCIATION WITH BONE MATRIX MINERALIZATION IN ADOLESCENT IDIOPATHIC SCOLIOSIS - A PILOT STUDY --- p.102 / Chapter 6.1 --- INTRODUCTION --- p.103 / Chapter 6.2 --- SUBJECTS AND METHODS --- p.104 / Chapter 6.2.1 --- Subjects --- p.104 / Chapter 6.2.2 --- Micro-computed tomography --- p.104 / Chapter 6.2.3 --- Bone histomorphometry --- p.104 / Chapter 6.2.4 --- Semi-quantification of OPN expression in bone biopsy by immunohistochemistry --- p.105 / Chapter 6.2.5 --- Plasma osteopontin measurement --- p.107 / Chapter 6.2.6 --- Statistical Analysis --- p.108 / Chapter 6.3 --- RESULTS --- p.108 / Chapter 6.3.1 --- Comparison of anthropometric parameters between AIS and control subjects --- p.108 / Chapter 6.3.2 --- Comparison of OPN expression detected by immunohistochemistry in bone biopsy between AIS and control groups --- p.108 / Chapter 6.3.3 --- Comparison of histomorphometric and micro-CT results between AIS and control groups --- p.109 / Chapter 6.3.4 --- Relationship between plasma OPN level and OPN expression in bone biopsy --- p.109 / Chapter 6.3.5 --- Relationship between percentage of low-mineralized bone and OPN expression in bone biopsy --- p.109 / Chapter 6.3.6 --- Relationship between material bone mineral density and OPN expression in bone biopsy --- p.110 / Chapter 6.4 --- DISCUSSION --- p.110 / Chapter 6.5 --- TABLES AND FIGURES --- p.114 / Chapter CHAPTER 7 --- SUMMARY STUDY FLOWCHART, OVERALL DISCUSSION, CONCLUSIONS, LIMITATIONS AND FURTHER STUDIES --- p.119 / Chapter 7.1 --- SUMMARY OF THE STUDY FLOW CHART WITH KEY FINDINGS --- p.120 / Chapter 7.2 --- OVERALL DISCUSSION --- p.125 / Chapter 7.2.1 --- The novel findings on bone mineralization abnormality in AIS in this study --- p.125 / Chapter 7.2.2 --- OPN is a key modulator in AIS --- p.128 / Chapter 7.3 --- OVERALL CONCLUSIONS --- p.130 / Chapter 7.4 --- LIMITATION OF THIS STUDY AND FUTURE RESEARCH --- p.131 / Chapter APPENDIX A. --- CONSENT FORM OF AIS RESEARCH --- p.135 / Chapter APPENDIX B. --- CONSENT FORM OF BONE BIOPSY COLLECTION --- p.137 / Chapter APPENDIX C. --- MATERIALS AND REAGENTS INFORMATION AND PROTOCOL FOR SOLUTIONS PREPARATION --- p.138 / BIBLIOGRAPHY --- p.143
24

The La Jolla skeletal population : reconstruction of prehistoric life on the southern California coast

Heflin, Tori Diana January 2012 (has links)
No description available.
25

A preliminary investigation into the estimation of time since death from human skeletal remains by radioisotope and trace element analysis

Howard, Sheridan January 2008 (has links)
One of the first concerns for forensic anthropologists in dealing with skeletal remains in the Australian context is the determination of whether the remains are of anthropological, historical or archaeological interest. If fewer than 75 years have elapsed since death, remains are classified as anthropological and of forensic interest. However, an accurate and reliable method for estimating time since death (TSD) from human skeletal remains has thus far eluded forensic anthropologists. This study investigates the application in an Australian context of a novel approach proposed by Swift (2001) to dating skeletal remains from their contained levels of radioisotopes 210Po, 238U and 226Ra and trace elements. Radionuclide activity concentrations were determined using alpha and gamma spectrometry. Trace element concentrations were measured on three separate occasions using inductively coupled plasma mass spectrometry (ICP-MS). Discriminant analysis of the combination of activity concentration values for 210Po, 238U and 226Ra indicated the possibility of separation of bones derived from individuals who had died in the three eras of interest. Additionally, variations in the concentration levels of specific trace elements and certain inter-element relationships between elements also showed significant correlations with TSD. The study could not be exhaustive as access to human skeletal material was limited and additionally, the archaeological material had a different origin and post-death history to material from the more recent past. However, trend lines for inter-relationships between specific metals and for radionuclides indicated that all material fitted the same generally projected trends and as such, inferences with respect to variations of trace elements and radionuclides could be made with confidence. Bone radionuclide activity and calcium concentrations were all significantly higher in bones from the archaeological era than those from more recent eras, while trace lead concentrations contained in samples from the more recent historical era were significantly higher than those from other eras. Barium, lanthanum, rubidium, strontium, cerium and neodymium concentrations were all significantly correlated with one another and with radionuclide activity concentrations. Differences were found between the patterns of radionuclide activity and trace element concentrations between the skull and femur. The results of this study lend support to suggestions that multivariate analysis of trace element concentrations and radionuclide activity levels could aid in the estimation of time since death from skeletal remains in Australia. Although this study made use of only a limited amount of material, results clearly indicated the need to take into account variations arising from lifetime activities, diagenesis and bone type in applying the techniques to estimations of time since death. It highlights the need for a large-scale study using bone of known ages that systematically examines these influences on the estimation of time since death.
26

Les variations osseuses asymptomatiques du squelette postcranien : leur contribution à l'identification en anthropologie médico-légale / The asymptomatic osseous variation of postcranial skeleton : their contribution to the identification in forensic anthropology

Verna, Emeline 11 December 2014 (has links)
En anthropologie médico-légale la détermination du sexe, l'estimation de l'âge au décès et l'estimation de la stature sont des paramètres essentiels à la constitution du profil biologique d'un individu à partir de restes osseux. Toutefois uniquement à partir de ces trois paramètres les interprétations sont limitées, plusieurs individus peuvent partager un même profil. L'introduction et l'observation d'autres paramètres, comme les variations anatomiques, peuvent être un atout dans l'établissement du profil biologique le plus singulier et complet possible afin de ne correspondre qu'à un nombre très restreint d'individus voire à un seul individu. En plus des variations anatomiques, l'observation des marqueurs de posture et des anomalies congénitales asymptomatiques peut aussi se révéler être pertinente. Ils ont été regroupés sous le terme de Variations Osseuses Asymptomatiques (VOA). Cent-neuf VOA ont été recensées sur le squelette postcrânien et 82 ont été étudiées à partir de 1300 individus provenant de trois populations différentes : une population contemporaine (imagerie médicale), une population ostéologique de référence et une population ostéoarchéologique. Pour chacune des VOA, la fréquence a été obtenue à partir des trois échantillons puis une fréquence en fonction du sexe, de l'âge et de la latéralité a été calculée. Une iconographie claire de chaque VOA a été obtenue. L'intérêt final est de ne sélectionner que les VOA ayant une fréquence inférieure à 10 % et facilement observables afin d'aider à l'identification en complétant le profil biologique, et ceci à partir d'une méthode basée sur la comparaison de données ante et post-mortem. / In forensic anthropology, determination of sex, estimation of age at death and estimation of stature are essential parameters for constituting the biological profile of an individual from bone remains. However, using only three parameters limits interpretation, several individuals could share the same profile. The introduction and observation of others parameters, particularly anatomical variations, could help establish a more complete and specific biological profile to correspond to a restricted number of individuals or to a unique individual. In addition to anatomical variations, postural markers and congenital anomalies can be useful for identification purposes. These 3 elements are regrouped under the term Asymptomatic Osseous Variation (AOV). 109 AOVs were found on the postcranial skeleton and 82 were studied on 1300 individuals from three different populations: a contemporary population (medical imaging), an osteological collection of reference and an osteoarcheological population. Frequencies were obtained from the three samples for each AOV, and frequencies according to sex, age and laterality were calculated. A clear iconography of each AOV was obtained. This data enabled the classification of the AOVs according to 5groups of frequencies, ranging from very rare to very frequent. The AOVs were also classified according to their liaison with sex, age and laterality. The final goal is to select only AOVs with a frequency inferior to 10% (qualified as rare), that are easily observable, to be useful for establishing the biological profile and help identify the individual, using a method based on ante and post-mortem data comparison.
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A comparative microscopic study of human and non-human long bone histology

Nor, Faridah Mohd January 2009 (has links)
Identification of human or nonhuman skeletal remains is important in assisting the police and law enforcement officers for the investigation of forensic cases. Identification of bone can be difficult, especially in fragmented remains. It has been reported that 25 to 30% of medicolegal cases, which involved nonhuman skeletal remains have been mistaken for human. In such cases, histomorphometric method was used to identify human and nonhuman skeletal remains. However, literature has shown that histomorphometric data for human and nonhuman bone were insufficient. Additionally, age estimation in bone may help in the identification of human individual, which can be done by using a histomorphometric method. Age estimation is based on bone remodeling process, where microstructural parameters have strong correlations with age. Literature showed that age estimation has been done on the American and European populations. However, little work has been done in the Asian population. The aims of this project were thus, to identify human and nonhuman bone, and to estimate age in human bones by using histomorphometric analysis. In this project, 64 human bones and 65 animal bones were collected from the mortuary of the Universiti Kebangsaan Malaysia Medical Centre and the Zoos in Malaysia, respectively. A standard bone preparation was used to prepare human and nonhuman bone thin sections for histomorphometric assessment. Assessments were made on the microstructural parameters such as cortical thickness, medullary cavity diameter, osteon count, osteon diameter, osteon area, osteon perimeter, Haversian canal diameter, Haversian canal area, Haversian canal perimeter, and Haversian lamella count per osteon by using image analysis, and viewed under a transmitted light microscope. The microstructural measurements showed significant differences between human and nonhuman samples. The discriminant functions showed correct classification rates for 81.4% of cases, and the accuracy of identification was 96.9% for human and 66.2% for animal. Human age estimation showed a standard error of estimate of 10.41 years, comparable with those in the literature. This study project offers distinct advantages over currently available histomorphometric methods for human and nonhuman identification and human age estimation. This will have significant implications in the assessment of fragmentary skeletal and forensic population samples for identification purposes.
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Paleodemography of Highland Beach the demographic parameters of a Native American population from Southeastern Florida

Unknown Date (has links)
Those who practice within the field and those who wish to discredit the field have long debated the field of paleodemography. In 1999 and again in 2000, researchers who used paleodemographic analysis assembled in Rostock, Germany to amend the present issues and change the way research is conducted in the future (Hoppa and Vaupel 2002). As a result of these meetings, researchers created the Rostock Manifesto. While many scholars accepted the change in the suite of methodologies carried out under the new guidance, little has been said on the effectiveness of the manifesto. In this thesis, I argue that the Rostock Manifesto, at the very least, is effective in changing the results of paleodemographic research both qualitatively and quantitatively. Unfortunately, due to the nature of paleodemographic research it cannot be said of how effective the manifesto is. / Includes bibliography. / Thesis (M.A.)--Florida Atlantic University, 2015 / FAU Electronic Theses and Dissertations Collection
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Abnormal skeletal growth and bone remodeling in adolescent idiopathic scoliosis: a morphological and genetic study. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Adolescent idiopathic scoliosis (AIS) is a complex three-dimensional structural spine deformity with lateral curve and vertebral rotation occurring predominantly in adolescent girls during the peri-pubertal period. The prevalence of AIS is nearly 4% in Hong Kong and 2-3% worldwide. AIS without treatment or with improper treatment may deteriorate progressively and lead to significant cosmetic problems and functional disabilities. In severe cases, increased mortality rate can result from the associated early onset of cardiopulmonary failure. Up to now, the treatment of the AIS is basically passive through bracing and corrective spinal surgery. The current protocol of treatment is not totally satisfactory since the curve may continue to progress with brace treatment and corrective surgery is associated with major surgery and permanent fusion of parts of the spine. This is due to the fact that one is still uncertain about the etiology of AIS and therefore cannot directly treat the AIS. Among the different proposed etiology of AIS, the role of abnormal skeletal growth and development during peri-pubertal period has been one of the main focuses in addition to genetic predisposition in the development of AIS. / It has been well established that girls with idiopathic scoliosis have a tendency to be taller and more slender than their peers. Recently, it has been shown that the trabecular bone mineral density at the spine, hip, and peripheral bones of AIS girls was lower than their healthy peers. Studies from our center have also demonstrated growth discrepancy between anterior and posterior vertebral column using magnetic resonance imaging (MRI) technique. The vertebral bodies were shown to be slender in AIS patients than that in normal controls. The observation pointed to a disproportionate growth of the anterior and posterior spinal column resulting from imbalance in endochondral and membranous ossification. The present study hypothesizes that the abnormality of skeletal growth could be a systemic problem affected by both endochondral ossification and membranous ossification. The degree of abnormal growth could vary with different curve severities. The concurrent finding of abnormal skeletal growth and osteopenia could be related to certain underlying abnormal genetic factors affecting the etiopathogenesis of AIS. The hypothesis leads to the following objectives: (1) To study the anthropometric measurements and the related changes in AIS girls with different curve severity; (2) To document the presence of abnormal systemic growth through endochondral ossification; (3) To document the presence of abnormal membranous ossification through studies of the morphology and bone mineral density of the midshaft of the appendicular skeleton and the skull; (4) To study the association of occurrence of AIS and its related phenotypes with the genes associated with growth and osteopenia. (Abstract shortened by UMI.) / by Yeung Hiu-Yan. / "January 2006." / Adviser: Jack C. Y. Cheng. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6301. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 206-227). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
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DNA analysis of human skeletal remains associated with the Batavia mutiny of 1629

Yahya, Padillah January 2008 (has links)
In this thesis human skeletal remains believed to be the victims of the Batavia Mutiny of 1629 were subjected to DNA analysis. So far the remains of 10 individuals (of which 9 were available for this study) have been exhumed from Beacon Island, in the Houtman’s Abrolhos, off the coast of Western Australia. The remains are now stored in the Western Australia Maritime Museum (WAMM) in Fremantle. In this research an attempt is made to type ancient DNA (aDNA) from the remains of the Batavia Mutiny, which are almost 400 years old. Previous anthropological studies have been performed on these remains in order to assign sex, age and stature. The aim of the present project is to study the familial relationships of the remains and to determine their sex based on molecular genetic analysis. In order to protect the invaluable museum specimens and minimise the risk of contamination from exogenous contemporary DNA, a tooth sample from each available individual (designated A15507, A16316, A15831, M3901, SK5, SK6, SK7, SK8 and SK9) was subjected to DNA extraction. Comparison and optimisation of DNA extraction methods from more recent teeth samples was performed in order to determine the most suitable method for the DNA extraction of the ancient teeth samples. Three types of genetic markers were analysed in an attempt to study the familial relationships and determine the sex of each individual. Multiplex primers (Hummel, 2003) which simultaneously amplify the HV1 and HV2 regions of mitochondrial DNA (mtDNA) were used in this research to analyse familial relationships. These primers were selected because of their ability to amplify small fragments (131bp, 168bp and 217bp) of DNA template, which suit the nature of aDNA samples. Primers published by Sullivan et al.(1993), which amplify a 106bp region on chromosome X and 112bp on chromosome Y of the amelogenin gene, were used to determine sex. In addition, short tandem repeat (STR) marker were also analysed to determine familial and sex using the AmpFlSTR®Profiler PlusTMPCR kit from Applied Biosystems. The PCR conditions of all primers were optimised before usage on the Batavia remains. As aDNA analysis is prone to contamination, stringent precautions were undertaken throughout this research. Despite this, contamination is suspected in some of the mtDNA sequences obtained (particularly from SK5, SK7, A15507 and A15831), which most probably came from the positive control used in the optimisation analysis. For these samples the sequences for the HV2 region were poor and polymorphisms relative to a reference were similar to each other and to the positive control profile. However, some conclusions have been made on other individuals (SK8, SK9, M3901, A16316) based on the HV1 and HV2 sequences obtained. Based on two or more different polymorphisms observed in the individuals it was concluded that it is likely there is no maternal relationship between individuals A16316 and SK8, SK9 and M3901 and between individuals SK8, M3901 and SK9. However these results require repetition for confirmation. The attempt to type the amelogenin gene on chromosomes X and Y was unsuccessful most likely due to the poor preservation of the remains. It is apparent from this research that although it was possible to extract aDNA (especially multicopy mtDNA) from teeth material that were almost 400 years old, the main hurdle in this aDNA analysis was contamination and DNA degradation.

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